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http://publish.illinois.edu/ymb/category/flotsam/amusements-daily/ | # Archive | amusements
## taxes and incentives at work
For some reason I remembered yesterday that opinion by Greg Mankiw from 2010 where he warned us that the (then feared) tax hikes by Obama admin would diminish his personal incentives to work. He was talking very directly about his output as articles which we would miss: to quote, “I [would] supply less of my services[…;] because you are reading this article, you are one of my customers.”
I thought it would be interesting to check what the 2017′ Tax Cuts and Jobs Act did to Mankiw’s productivity.…
## alons enfants de la patrie
In collaboration with Cynthia Sung, Daniel Feshbach and bloodthirsty French people……
## Protected: lake wobegon academic publishing
There is no excerpt because this is a protected post.
## MATH 199, Monday April 29: Around Arrow
We will be talking about Arrow’s Impossibility theorem, and its topological relatives. The span of the talk will be between American political landscape and elementary algebraic topology – feel free to peruse the links and their vicinity!
Follow-up exercise: try to model your decision process next time you are trying to converge with your friends or relatives, where to go out, or what to watch together. What is the topology of your movie-space?…
## Fact of the day: Functions with given merge tree
$$\def\Real{\mathbb{R}}$$
Consider a Morse function on $latex f:\Real^n\to \Real$ with controlled behavior at infinity, – say, $latex f=|x|^2$ near infinity. Assume further that all critical values $latex a_1<a_2<\ldots<a_k$ are distinct and that all indices of critical points are $latex 0$ or $latex 1$. (Condition obviously holds in one variable.)
Clearly, there are many function that satisfy these conditions. In the (again, most transparent) univariate case, the enumeration of topological types of functions with given critical values is the subject of a nice thread of papers by Arnold on “snakes” (see, e.g.,…
## Mapping department strength
What is your math department strength? One of those rather polarizing questions, or an opportunity to gossip without guilt.
Still, important to understand where your department is on the map, if one wants to steer it in some particular direction, or to keep it where it is.
I wrote a short python script, using BeautifulSoup (thank you!) and campus-wide subscription to MathSciNet (thank you too!) – and downloaded the raw numbers: how many items (whichever MathSciNet is indexing: articles, books, theses,…) are authored by folks from ‘1-IL’ (our code) vs.…
## Voice of Russia puts Urbana on the war map (never mind the grammar or arithmetic)
From voiceofrussia.com:
“A new wave of a massive D-Dos attack hit our site at 1 o’clock pm last night,” the organizers of the Crimean referendum have just reported.
“Our IT safety experts managed to find out where those attacks came from. It is University of Illinois at Urbana Champaign. The most powerful scanning of servers before the attack was carried out exactly from there.”
It is significant that Urbana – Champaign, with a population of 37,000, has the highest number of subnets with IP addresses. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3261929750442505, "perplexity": 3117.441908317352}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964363641.20/warc/CC-MAIN-20211209000407-20211209030407-00618.warc.gz"} |
http://yuzo.realizzazionifaidate.it/ansys-shock-analysis.html | # Ansys Shock Analysis
Experimental and Finite Element Analysis of Preloaded Bolted Joints Under Impact Loading. Water evaporate below saturation temperature. Analysis Methods Used in TN-LC Transport Cask Analysis NCT • MP197HB Transport Cask Body • 3D ANSYS Model • Elastic/Equivalent Static Analysis • Lid Bolt • Evaluated based on NUREG-6007 methodology and criteria • Upper Trunnions • Evaluated for critical loads by hand calculations using ANSI N14. Harmonic analysis done to assess the dynamic behaviour of the Gear Box and shock analysis is performed to analyse the shock response of the Gear Box under shock load. Introduction. And also the analysis was performed by using ANSYS is a general purpose finite element analysis (FEA) software package. While shock absorbers serve the purpose of limiting excessive suspension movement, their intended sole purpose is. Vibration Modal Analysis of Landing Gear Based on ANSYS. (ANSS) including details of assets, liabilities and shareholders' equity. Design and analysis of a swinging jaw plates of a single toggle jaw crusher: SOLID WORKS/CATIA/PTC CREO/UNX: SOLID WORKS/ANSYS/CATIA: Download: Download: 36. , a wholly owned subsidiary of Leidos, on their study contract award for the NASA - National Aeronautics and Space Administration Human Landing System Program. We perform computational modelling, including random, sine, shock, fatigue, and thermo-elastic analysis for both metallic and composite structural parts and. Is the constraint method used satisfactory for the shock analysis of the APA frame? Note: – This question is independent of the constraint system used for vibration analysis. 0}, author = {Toth, Sandor and Legradi, Gabor and Aszodi, Attila}, abstractNote = {From the aspect of planning the power upgrading of nuclear reactors - including the VVER-440 type reactor - it is essential to get to know the flow field in the fuel assembly. Different modules of FEA programs each handle different kinds of vibration problems. 1, we can obtain the best suitable material among the materials chosen. A software model is prepared in Solid works software and for finite Element analysis the design is tested against all modes of failure by conducting various simulations and stress analysis with the aid of Ansys Software (14. This work aims at. Shock absorbers are mounted alongside (or insi ICMPC 2017 Design and Analysis of Shock Absorber: A Review 7 Elsevier Ltd. FEA consulting is at the heart of what we do at BroadTech Engineering Singapore. Keywords: shock analysis, impulse analysis, dynamic response, finite element analysis (FEA), ansys workbench, shock experiment, deformation, impeller, acceleration, pulse width, 3d model. I have done CFD analysis in Fluent can i use these results in FSI. Look at latest prices, expert reviews, user ratings, latest news and full specifications for Samsung Galaxy Y. • Involved with FEM analysis on various type of model from simple static to non-linear contact for plastic part assembly. Technical reports preparation. However, the Super Bowl also highlighted the continuing problem of concussion and head injuries in the NFL. With Ansys I cannot run a modal superposition analysis due to the fact that I am using a displacement constraint (I was informed by an Ansys representative that this is the case) so ran a full transient analysis with the direct solver. The geometry of this model is described in the Table 4 below:. Poornamohan 1, Lakshmana Kishore. 0 The purpose of this tutorial is to show the steps involved to perform a simple transient analysis. Key Words: Shock Absorber, Automotive, CAD, FEA, ANSYS, spring. My model has two parts connecting with some spotwelds. ANSYS provides a comprehensive suite of computational fluid dynamics software for modeling fluid flow and other related physical phenomena. By validate the procedure in ANSYS 16. Experimental shock test is also carried out to composite foundation. In this paper, ANSYS-Workbench finite element analysis software sequential electro- thermal coupling method is used to analyze the electric-thermal coupling field of the electric-ignition temperature rise process of the electrical initiator bridge. Which is first developed for structural physics that could simulate static i. 0 was carried out. Master Degree taught by the Technical University of Madrid in collaboration with ANSYS Inc. World Journal of Mechanics Vol. Here, both the transient and the steady states. My experience is that typically the most time consuming part is writing the APDL script. The study of the dynamic behavior of free vibration structures is done by modal. model and take the different spring cross section and analysis of this model using ANSYS 15. pronounced effect on the shock spectra that an individual equipment may experience. In the present work, a down-to-the-hole electric hammer driven by linear motor is reported for drilling engineering. o Modal Frequency analysis o Board bending o In circuit test (Static structural) o Mechanical shock (Transient dynamic) o Thermo-mechanical induced issues o Solder fatigue analysis o Stresses in vias during reflow o Warpage o This webinar concentrates on how Sherlock can accelerate the analysis capabilities of FEA solvers. If modeling the ability of bodies to separate or open slightly is important and/or obtaining the stresses very near a contact interface is important, consider using one of the nonlinear contact types (Frictionless, Rough, Frictional), which can model gaps and. Nlgeom ansys Pricebaba brings you the best price & research data for Samsung Galaxy Y. A Study Of Shock Analysis Using The Finite Element Method Verified With Euler-Bernoulli Beam Theory; Mechanical Effects Due To Pulse Width Variation Of Shock Inputs; And Evaluation Of Shock Response Of A Mixed Flow Fan David Jonathan González Campos For many engineers that use finite element analysis or FEA, it is very important to know how to properly model and obtain accurate solutions for. ANNA UNIVERSITY CHENNAI :: CHENNAI 600 025 AFFILIATED INSTITUTIONS REGULATIONS ¡V 2008 CURRICULUM AND SYLLABI FROM VI TO VIII SEMESTERS AND. PSD random vibration input (Based on Danfoss Corporate Guideline 500B0432 curve A) will be provided at this stage. edu is a platform for academics to share research papers. Through Finite Element Analysis (IL: Finite Element Analysis), we are able to help you to solve complex structural engineering challenges so as to allow you to make an informed and precise engineering design decision within a shorter period of time. 1 catia Fig 3. The analysis is done by considering load of bike weight, load of single person and load of two persons. Changing situation of buckling of thin-walled shells under axial impact force was discussed from the aspects of mesh density,material properties,element type,contact type,hourglass control by using ANSYS/LS-DYNA. They are considering shock spectrum boundary condition for drop test simulation. See more ideas about Ansys, Cfd simulation, Computational fluid dynamics. The analysis will consider the loads, bike weight, single person and 2 persons. abbreviations shown below:. Thermal Shock Analysis in Ansys Workbench You will have to register or login (See top or bottom of page) before you can post a message or view images: click the appropriate link to proceed. 0 The purpose of this tutorial is to show the steps involved to perform a simple transient analysis. Depend-ing on the type of analysis, it is necessary to choose the element type with. PCB Reliability Analysis with Ansys. Aghazarian, Ts. Some load types can be applied with a phase offset. 1, we can obtain the best suitable material among the materials chosen. 2014 | 41 | Structural Analysis of Ladder Chassis Frame for Jeep Using Ansys Vishal Francis1 , Rajnish Kumar Rai2 , Anup Kumar Singh3 , Pratyush Kumar Singh4 , Himanshu Yadav5 1. One of the benefits of performing finite element analysis is to solve design challenges without arduous manual iterations or prototyping - as well as to. Videos - Classical Hand Calculations in Structural Analysis: Here is an example video on Heel Toe or Prying Effect, another standard method of Classical Hand Calculations in Structural Analysis. 13 Oct 2016 steel-composite rocket nozzle is carried out using ANSYS. But as machines with. Techniques used include the following, but see Engineered Design section below for a list of software and other tools used:. ANSYS Workbench can be used to perform the modal analysis of a structure in rotation. However, quick. develops, markets and supports engineering simulation software for design analysis and optimization. Further validation of software Msc NASTRAN is used to compare the results of modal analysis of composite foundation in ANSYS. Anisotropic material properties in ANSYS I am trying to analyse the behaviour of 3d printed parts made from ABS plastic under load. ANSYS Acquires Assets Of Electronics Automated Design Analysis Leader DfR Solutions Acquisition gives customers access to premium electronics reliability technology PR Newswire PITTSBURGH, May 1. Finite element analysis (FEA) software from ANSYS provides engineers the ability to automate and customize simulations and even parameterize them for many design scenarios. Structural analysis are done on the shock absorber for various material, Spring Steel and Carbon fiber. Numerical analysis of the underwater explosion phenomena is implemented in the nonlinear finite element code ABAQUS/Explicit. Transient dynamic analysis is a technique used to determine the dynamic response of a structure under a time-varying load. [FREE] Ansys Transient Structural Tutorial Pdf Welcome to the M echanic al APDL In troductory Tutorials. PITTSBURGH, May 1, 2019 /PRNewswire/ -- ANSYS (NASDAQ: ANSS), the global leader and innovator of engineering simulation software, announced today that it has acquired substantially all the assets of DfR Solutions, the developer of Sherlock, the industry's only automated design reliability analysis software. ANSYS BasicsStarting ANSYS Launcher (cont™d) ŁAutomatically brings up the GUI (Graphical User Interface) when ANSYS is started in interactive mode. I fully plan to hit up my colleagues for similar blog posts about heat transfer, CFD, and electrical simulation. During the Batch ANSYS run that reads in the ds. com is a ~7 years old website dedicated to Finite Element Analysis beginner and advanced users, where unique tutorials, already solved FEA, books and webinars provide expertise and skills nowhere else to be found on the Internet but here. ANSYS Sherlock Capabilities Leveraging Physics of Failure Physics of Failure (PoF), or Reliability Physics, uses degradation algorithms that describe how physical, chemical, mechanical, thermal or electrical mechanisms can decline over time and eventually induce failure. txt) or read book online for free. ANSYS Explicit Dynamics analysis software provides simulation technology to help simulate structural performance long before manufacture. abbreviations shown below:. The Mechanical APDL Introductory Tutorials provide an introduction to the extensive capabilities of the Mechanical APDL family of products. The problem is that the first six modes (rigid body modes) are not equal to zero (some around 30 hz). Index Terms: damp shock, kinetic energy, Pro/Engineer, and ANSYS, shock absorber -----***----- 1. Step by step procedure of how to do transient structural analysis (varying load/force with time) of a bridge ANSYS 13 workbench. Modeling and Analysis is done by using Pro/ENGINEER and ANSYS respectively. 3:Section model 50 mm element 30 Hz. Deformation,stress distribution,strain distribution of the steel pipe at different moments were obtained. The software suite delivers accurate, robust, high-performance solutions for challenging nonlinear problems, large-scale linear dynamics applications, and routine design simulations. By combining the time efficiency of Pro/Engineer and the analytical power of ANSYS Multiphysics, the analyses were performed quickly, yet still with the high level of detail needed to identify problem areas and solutions. 0}, author = {Toth, Sandor and Legradi, Gabor and Aszodi, Attila}, abstractNote = {From the aspect of planning the power upgrading of nuclear reactors - including the VVER-440 type reactor - it is essential to get to know the flow field in the fuel assembly. Web Help Content Version: SOLIDWORKS 2017 SP05 To disable Web help from within SOLIDWORKS and use local help instead, click Help > Use SOLIDWORKS Web Help. beryllium copper. Displacement mode 1 and mode 2 from the modal analysis 𝜃1[𝑀𝑜 1]= 0 6. Here the analysis of flow of nozzles is done by using CFD. This study will improve the stability and performance of the shock absorber. Static structural analysis is only concerned with finding a solution to the equation of motion in the form of: $\mathbf{K} \mathbf{u} = \mathbf{F_{ext}}$ In non-mathematical words: the inertia (mass and rotational inertia) aren't taken. Description & Purpose A response-spectrum analysis calculates the maximum response of a structure to a transient load. PRAKASH1*, K. 2016-2019) to peer-reviewed documents (articles, reviews, conference papers, data papers and book chapters) published in the same four calendar years, divided by the number of. Free fall drop impact analysis was carried out using Drop Test Module of ANSYS V 10. You have Direct Transient Analysis, Modal Analysis, Explicit Transient Analysis (the funniest type ;-) ) Continue to follow me to understand more about all these analyses :-). The contents of the book are mainly divided into three parts based on the type of loading imparted to the granular materials: Shock-wave loading (step pulse); Air-blast loading. ANSYS Explicit Dynamics Analysis Guide - Free ebook download as PDF File (. The diaphragm will be removed instantaneously and so fluid with higher pressure will move to the lower pressure region and thus creating a shock wave to the front. In this analysis, maximum shear stress and total deformation is calculated using ANSYS software and the comparison is made on two material. The shock overload event was found to last 0. Von-mises stress is calculated using theoretically and FEA software ANSYS. Batch mode: ŒInteractive mode allows you to interact filivefl with ANSYS, reviewing each operation as you go. By this 30 rpm speed of the motor, this will give the angular velocity of the crank by the formula for angular velocity. com | 800-882-5762 92016GS Hydraulic Gear Pump and Motor Failure Analysis and Repair Guide The heart of a hydraulic system is the hydraulic pump. i have to measure evaporated water quantity. Our state-of-the-art computing cluster paired with the full suite of Ansys® FEA tools enables us to tackle any type of problem, no matter the scale or complexity. The analysis is done by considering load of bike weight, load of single person and load of two persons. - Free Vibration with Pre-Stress Analysis Procedure • The capabilities described in this section are generally applicable to ANSYS DesignSpace Entra licenses and above. verify the best dimension for the spring in shock absorber. Starting with version 3. Here we have the collection of presentations given by Ozen Engineering and Ansys at the Convergence Conference. ANSYS Acquires Assets Of Electronics Automated Design Analysis Leader DfR Solutions: ANSYS (NASDAQ: ANSS), the global leader and innovator of engineering simulation software, announced today that it has acquired substantially all the assets of DfR Solutions, the developer of Sherlock, the industry's only automated design reliability analysis software. We tested it on a NVIDIA GTX 980, and had no noticeable issues. Enidine Inc. The horizontal axis shows the natural frequency of a hypothetical SDOF, and the vertical axis shows the peak. ANSYS Mechanical APDL Command Reference. Hence this report explains its working, modelling and analysis of the parts. This volume discusses the fundamental dynamic behavior of granular materials, in particular cohesionless sand, when subjected to shock and blast wave loading. NOTE: I have never used DES, so my answer will be based on my knowledge of the topic, based on my experience with LES and RANS. Advanced Structural Analysis using ANSYS Workbench 30,000. act as a shock absorber and decrease stress on part of. In a vehicle, it reduces the effect of travelling over rough. Structural Analysis of Ladder Chassis Frame for Jeep Using Ansys 1. The shock absorbers duty is to absorb or dissipate energy. 2 “Study of the thermal behaviour of dry contacts in the brake discs « application of software ansys v11. Which is first developed for structural physics that could simulate static i. FEM analysis (FEMAP/NASTRAN) of satellite structures and components: quasi-static loads, random vibrations, shock response spectrum, sine-equivalent dynamics, thermoelastic loads. For 61BT/61BTH baskets, the evaluation is based on elastic analysis XNon-linear elastic-plastic analysis is used for HAC loads. Tools used: ANSYS WB, KissSoft (bolt calculation). When a vehicle is traveling on a. Mehr anzeigen Weniger anzeigen. Comparisons. Ansys Stress Analysis Tutorial (Shock) Analysis of. 0,OptiStruct 13. Once these simulations are completed, the results file is read back into Sherlock, and strain values for each component are extracted and applied to either Basquin or Coffin—Manson. Six subphenotypes in septic shock: Latent class analysis of the PROWESS Shock study. •Share methods of analysis and help you understand their applications and limitations. They included a destructive test of a prototype wing. beryllium copper. Sort by Date. PSD A power spectral density (PSD) takes the amplitude of the FFT, multiplies it by its complex conjugate and normalizes it to the frequency bin width. DESIGN AND ANALYSIS OF STRUT ASSEMBLY COIL SPRING BY VARIOUS MATERIALS USING ANSYS S. Ranjeet Kumar3 1M. ANSYS software for structural analysis allows you to solve your most complex structural engineering projects and make superior design decisions more quickly. " ‘Shock Troop 1917’ Is a Brutal War Film … From 1934 " "The movie was popular with German nationalists" "Hans Zöberlein’s 1934 feature film Stoßtrupp 1917 — Shock Troop 1917, in English — depicts German storm troopers fighting on the Western Front during World War I, slogging from the Aisne to Champagne to Cambrai. ANSYS VALIDATION OF THE SOFTWARE FOR BLAST ANALYSIS For the purpose of numerical validation, a twin tunnel in New York, similar to the one in Bangalore is selected, and a finite element model was developed using ANSYS. >having some hyper elastic material by using modal analysis in Ansys. Structural Performance Improvement of Shock Absorber with Carbon Fiber and Beryllium using ANSYS Structural Manish Belwanshi1 D. cbrn (Mechanical) 27 Oct 06 03:55. When a material is loaded too much, it may break even if the resultant stress is less than the Ultimate stess. Thermal Shock Analysis by ANSYS Mechanical with Statistical Analysis. A numerical simulation has been carried out to examine the response of steel plates with different arrangement of stiffeners and subjected to noncontact underwater explosion (UNDEX) with different shock loads. com Commonly used in the analysis of: • Nuclear power plant buildings and components, for seismic loading • Airborne Electronic equipment for shock loading • Commercial buildings in earthquake zones Types of Response Spectrum analysis: Single-point response spectrum • A single response spectrum excites all specified points in the model. Therefore, the angle of attack is simply the angle between the free stream and the chord line. This is only to consider the input information for ANSYS. In this analysis, maximum shear stress and total deformation is calculated using ANSYS software and the comparison is made on two material. Tianjin University of Technology and Education. Structural Design & Analysis Static and Dynamic structural analysis (random vibration, harmonic, acoustic, shock, buckling, and fatigue) is performed using proprietary tools and state of the art industry software packages such as ANSYS Multiphysics, MSC Nastran, and Patran. In this method, the time domain transformation of self-exited force is realized by means of adding aerodynamic stiffness and aerodynamic damping element to FE model. 02(2020), Article ID:99002,15 pages 10. Structural Dynamic Analysis in Dana Point. Finite element analysis (FEA) software from ANSYS provides engineers the ability to automate and customize simulations and even parameterize them for many design scenarios. The analysis is done by considering loads, bike weight, rsons. My experience is that typically the most time consuming part is writing the APDL script. Analytic calculations are done to determine the stress and deflections. (NASDAQ:ANSS) Q1 2020 Earnings Conference Call May 7, 2020 08:30 ET Company Participants Lee Detwiler - VP Finance Ajei Gopal - CEO Maria Shields -. With a point-and-click interface and tools for batch operations, Origin helps them optimize their daily workflow. Structural and Modal Analysis of Shock Absorber of Vehicle Rahul Tekade1, Chinmay Patil2 ANSYS Workbench 11. -Will the Transport Frame Report provide the analysis of the shock. Together with our customers, we achieve higher performance in mechanical, structural, and aerospace products. TECH (Machine Design) Sana Engineering College, Kodad [email protected] Join us for an informational overview of these key technologies to learn how Ansys solutions can help you develop the best electronics products possible. Environmental pollution and rapid depletion of fossil fuels had necessitated the search for alternative technologies and energy sources for transportation. Adult patients presenting with sepsis (defined as the presence of two or more systemic inflammatory response syndrome criteria with documented or suspected infection), lactate greater than 3 mmol/L, and hypotension (systolic pressure. NOTE: I have never used DES, so my answer will be based on my knowledge of the topic, based on my experience with LES and RANS. Informazioni. 0,OptiStruct 13. Guarda il profilo completo su LinkedIn e scopri i collegamenti di Luigi e le offerte di lavoro presso aziende simili. Design and optimization of Francis turbine's stay-vanes and guide-vanes using CFD analysis with ANSYS CFX and Turbogrid 1301 with 24-hour thermal shock cycle. Journal of Energetic Materials: Vol. XThe Limit analysis provisions of ASME Code Section NG 3228. Technical Support: Reaction Design provides an allotment of technical support to its Licensees free of charge. design skills. The primary objective of this Ansys Dynamics Training class is to teach participants Structural Dynamic Analysis using the Ansys Mechanical Workbench platform. 1 FUNCTIONS OF SHOCK ABSORBERS IN AUTOMOBILE In common with carriages and railway locomotives, most early motor vehicles used leaf springs. ansys analysis software ANSYS structural analysis software enables Supashock engineers to solve complex structural engineering problems and make better, faster design decisions. When a vehicle is traveling on a. In this FE analysis, initially it is proposed to achieve a shock pulse given in service condition B. World Journal of Mechanics Vol. Modal Transient Analysis The input acceleration may be available as a measured time history. outcomes, which is driven by the former, an FEM analysis has been done using the ANSYS Workbench, and the details are given in following section. HI-TECH PROJECT INDUSTRIES. com URL: www. Ansys Stress Analysis Tutorial (Shock) Analysis of. com •Transient structural analysis provides users with the ability to determine the dynamic response of the system under any type of time -varying loads. 1 Accelerometer Dynamics: Frequency Response, Damping, Damping Ratio, and Linearity Periodic Vibrations • Stationary Random Vibrations • Transients and Shocks • Nonstationary Random Vibrations 17. Founded in 1970, ANSYS employs thousands of professionals, many of whom are expert M. Graphical Comparison of the results from Bray’s solution vs. Analysis Methods Used in TN-LC Transport Cask Analysis NCT • MP197HB Transport Cask Body • 3D ANSYS Model • Elastic/Equivalent Static Analysis • Lid Bolt • Evaluated based on NUREG-6007 methodology and criteria • Upper Trunnions • Evaluated for critical loads by hand calculations using ANSI N14. From the chassis to components, we use ANSYS Finite Element Analysis to give you strong but lightweight and durable parts. Nlgeom ansys. Note that these apply to structural analysis. The shock load is applied in three directions (vertical, fore and aft, athwart ships) and the results show that the vertical direction is the most severe loading direction and critical to the functionality of the ramp. Ansys Autodyn Capabilities Solver Technology Ansys Autodyn lets you select from different solver technologies so the most effective solver can be used for a given part of the model. In this case theoretically the equations for nozzle are formulated and hence forth the final result is been validated for the simulation using CFD software ANSYS fluent of high speed jet the small vortices remains stable. Free fall drop impact analysis was carried out using Drop Test Module of ANSYS V 10. ansysinfo. • Mechanical Vibrations Analysis: Natural frequencies (Modal), Harmonics, Random Vibration – PSD, Shock loads (calculate stress, deformations, accelerations, transfer function). Get the annual and quarterly balance sheet of ANSYS, Inc. I have tried different models, in which there is a high-pressure region and a low-pressure region which generates a shock wave. A Shock Response Spectrum (SRS) is a graphical representation of a shock, or any other transient acceleration input, in terms of how a Single Degree Of Freedom (SDOF) system (like a mass on a spring) would respond to that input. A simplified method used to predict the buffeting responses of long-span bridges in time domain is developed on the basis of ANSYS. Analytical as well as experimental efforts have been undertaken to predict the shape of the jet plume and its effects on the airplane’s sonic boom. 248 Hz 230 Hz Part. A) Set Time at end of loadstep to 300 and Automatic time stepping to ON. Verification I: Base Plate The transient response of the proposed method is applied to the base plate of a 2. ansys analysis software ANSYS structural analysis software enables Supashock engineers to solve complex structural engineering problems and make better, faster design decisions. Generally, the shock should be compressed 40% - 50% of its travel at ride height. The software used to perform analysis was ANSYS v14. ANSYS Workbench Transient Structural Analysis Tutorial. Developing designs, Finite Element Analysis and calculations. a tension bar with one end surface fixed in all direction. PITTSBURGH, May 1, 2019 — ANSYS (NASDAQ: ANSS), the global leader and innovator of engineering simulation software, announced today that it has acquired substantially all the assets of DfR Solutions, the developer of Sherlock, the industry’s only automated design reliability analysis software. OUTLINE Importance and Motivation. RESULT AND DISCUSSION A. Finite Element Analysis is a numerical method of deconstructing a complex system into very small pieces (of user-designated size) called elements. , the question is - does anybody use Fluent for supersonic flows (M=4-12) with strong shock waves? How to use high order schemes (2nd upwind or 3rd MUSCL) in Fluent with strong shock? If somebody had experience with this problem, please, give some comments on it. 7 (39 ratings) Course Ratings are calculated from individual students’ ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately. The problem considered here is the vibration analysis of the right-angle frame in example 11. Choose the element type Choosing an appropriate element type for the numeric calculation is one of the most essential steps in the process-chain of the simulation. 9 Harmonic Analysis Used extensively by companies who produce rotating mach inery, ANSYS Harmon ic analysis is used to predict the sustained dynamic behavior of structures to consistent cyclic. I have to simulate a section of a shock tube, in which there is a shock wave. Structural Design & Analysis Static and Dynamic structural analysis (random vibration, harmonic, acoustic, shock, buckling, and fatigue) is performed using proprietary tools and state of the art industry software packages such as ANSYS Multiphysics, MSC Nastran, and Patran. Abstract Modal analysis is used to determine the vibration characteristics of the structure or machine part in the design, ie the natural frequency and mode. materials to verify best material for spring in Shock absorber. Analyses performed will span a wide range from hand calculations using engineering theory to finite element analysis (ANSYS) and non-linear system dynamics and mechanism simulation (MSC/Adams). For analysis process the project considered that to fix a DC motor of 30 rpm with 5 kg torque. The phrase "Explicit" refers to a type of time integration used to perform dynamic simulations. Further validation of software Msc NASTRAN is used to compare the results of modal analysis of composite foundation in ANSYS. Our state-of-the-art computing cluster paired with the full suite of Ansys® FEA tools enables us to tackle any type of problem, no matter the scale or complexity. A detailed analysis has been conducted of Tie6Ale4V processed by metallic shot peening and laser shock peening. Tools used: ANSYS WB, KissSoft (bolt calculation). Furthermore, high speed data was collected for shock load detonation events to document the failure sequence of a G/M seal under such loading. Example: Modal Analysis Using ANSYS Workbench. ANSYS’ comprehensive multiphysics solutions, combined with Sherlock’s accurate reliability analyses, will provide a complete designer-level toolkit enabling customers to quickly and easily analyze for electronics failure earlier. • Vibration, acceleration and shock analysis of radar and antenna structures as per military standards using ANSYS Mechanical • Vibration & shock testing for validation purposes • Analysis and experimental verification of composite Antenna radome. Harmonic analysis done to assess the dynamic behaviour of the Gear Box and shock analysis is performed to analyse the shock response of the Gear Box under shock load. 's Compact Wire Rope Isolator is made of all-metal, which gives the best multi-axis shock and vibration isolation. Nlgeom ansys Nlgeom ansys. With Ansys I cannot run a modal superposition analysis due to the fact that I am using a displacement constraint (I was informed by an Ansys representative that this is the case) so ran a full transient analysis with the direct solver. design skills. of ANSYS and its capability, backed up with the in-house developed software, for Underwater Explosion analysis of structures. Shock Analysis - Ansys After completion of the solution, reviewing transient structural analysis results typically involves the following output: • Contour plots and animations • Probe plots and charts Generating contour plots and animations are similar to other structural analyses • Note that the displaced position of rigid. In this project the helical spring of a shock absorber by using 3D parametric software CATIA. When a vehicle is traveling on a. For this analysis you'll need SolidWorks Simulation Premium to run a linear dynamic - time history analysis. This study will improve the stability and performance of the shock absorber. The shock absorbers duty is to absorb or dissipate energy. Some load types can be applied with a phase offset. 2Professor, Department of Mechanical Engineering, Aarupadai Veedu Institute of Technology, India. Temperature and stress distribution of a stop valve under thermal shock from a hot fluid flow. The deformation of the structure at various natural frequencies using buckling and vibration analysis were introduced. Modeling is done in CATIA and analysis is done in ANSYS. The horizontal axis shows the natural frequency of a hypothetical SDOF, and the vertical axis shows the peak. Here the analysis of flow of nozzles is done by using CFD. of ATUCHA II NPP Reactor Pressure Vessel for Pressurized Thermal Shock Analysis, Nuclear Energy For New Europe 2008, Pages 702. In this method, the time domain transformation of self-exited force is realized by means of adding aerodynamic stiffness and aerodynamic damping element to FE model. 7207839 Ansys Structural Analysis Guide - Free ebook download as Text File (. In this paper, a finite element (FE) model is firstly developed in ANSYS for the ST drive from Seagate. • Conducted Ansys advance training on non-linear analysis; material and geometry non-linearity, geometry clean up and trouble shooting on problematic geometry. ATA engineers innovate to solve problems and can help implement new methods for test, analysis, and design in your organization. This classification contains four classes of shock and shows good correlation with acidosis, blood product need and mortality. We will use the defaults, so click OK. In a vehicle, shock absorbers reduce the effect of traveling over rough ground, leading to improved ride quality and vehicle handling. Direct Transient Response Analysis MSC/NASTRAN102 Exercise Workbook 3-21 POINT-ID = 11 D I S P L A C E M E N T V E C T O R TIME TYPE T1 T2 T3 R1 R2 R3 0. Domain : Finite Element Analysis, Structural Analysis. Reliability Physics Analysis for Implementing SAE J3168 Standard - Implementation with Ansys Sherlock. I basically want to model a shock tube, where pressurized air is kept behind a diaphragm in an enclosed tube, and at t=0 the diaphragm bursts and the pressurized air propagates in the enclosed tube. For analysis process the project considered that to fix a DC motor of 30 rpm with 5 kg torque. com is a ~7 years old website dedicated to Finite Element Analysis beginner and advanced users, where unique tutorials, already solved FEA, books and webinars provide expertise and skills nowhere else to be found on the Internet but here. Tools used: ANSYS WB, KissSoft (bolt calculation). Keyword-suggest-tool. This study will improve the stability and performance of the shock absorber. The FE model is verified by conducting a modal analysis of HSA. Transients are only for temperatures. MUHAMMADMARJAN3 1Research Scholar, Aarupadai Veedu Institute of Technology, Vinayaka Mission University, India. Hence for these ships ANSYS is used for Thermal Analysis. With those caveats in mind, here is our list of recommendations for Crawling, Walking, and Running with ANSYS. It is the most important step of CFD analysis. The problem considered here is the vibration analysis of the right-angle frame in example 11. PRAKASH1*, K. Transient responses exerted from RFR method are also approximated by simplified and SDOF models. Toth, Sandor; Legradi, Gabor; Aszodi, Attila. In the realization of mechanical structures, achieving stability and balance is a problem commonly encountered by engineers in the field of civil engineering, mechanics, aeronautics, biomechanics and many others. ANSYS virtually analyze how their products work in real world environment, at an early stage of product design. Using a Baja car, a transient dynamic impact is performed in ANSYS Workbench 14. You can also compare Samsung Galaxy Y with other mobiles, set price alerts and order the phone on EMI or COD across Bangalore, Mumbai, Delhi. Run the analysis in AUTODYN. This volume discusses the fundamental dynamic behavior of granular materials, in particular cohesionless sand, when subjected to shock and blast wave loading. Students learn best writing skills with read of grademiners review those are written by qualified writers of world. are done on the shock absorber by varying material for spring. Products are used to accelerate product time to market, reduce production costs, improve engineering processes, and optimize product quality and safety for a variety of manufactured products. The software suite delivers accurate, robust, high-performance solutions for challenging nonlinear problems, large-scale linear dynamics applications, and routine design simulations. When a vehicle is traveling on a. 0E10 Pa, ν = 0. @article{osti_20995466, title = {CFD Analysis of Coolant Flow in VVER-440 Fuel Assemblies with the Code ANSYS CFX 10. beryllium copper. am ABSTRACT. 's Compact Wire Rope Isolator is made of all-metal, which gives the best multi-axis shock and vibration isolation. Shock Design, Development and Testing One of the least appreciated components on a race car is the shock. PITTSBURGH, May 1, 2019 /PRNewswire/ -- ANSYS (NASDAQ: ANSS), the global leader and innovator of engineering simulation software, announced today that it has acquired substantially all the assets of DfR Solutions, the developer of Sherlock, the industry's only automated design reliability analysis software. Each type of model uses a different set of ANSYS contact elements and is appropriate for specific types of problems. Laser shock forming is a non-thermal laser forming method using the shock wave induced by laser irradiation to modify the curvature of the Therefore, FEA of LSF is composed of two distinct steps including dynamic analysis and static analysis. In 1995, it had been simulated the landing gear for BERKUT aircraft by using STARDYNE, and determined the stress generated on the root of. Therefore, CAD-FEM was interested in an interface between these two programs. I want to simulte evaporation from the free surface which is open to atmosphere. Finite Element Analysis is a numerical method of deconstructing a complex system into very small pieces (of user-designated size) called elements. ANSYS workbench 16. Specifies the velocity spectrum computation constants for the analysis of shock resistance of shipboard structures. Temperature and stress distribution of a stop valve under thermal shock from a hot fluid flow. [FREE] Ansys Transient Structural Tutorial Pdf Welcome to the M echanic al APDL In troductory Tutorials. Structural analysis is done to validate the strength and modal analysis is done to determine the displacements for different frequencies for number of modes. Is the constraint method used satisfactory for the shock analysis of the APA frame? Note: – This question is independent of the constraint system used for vibration analysis. Can be exported for current density, thermal, or structural analysis. Fatigue Analysis tells us how the material reacts to these loads with respect to Time. Visualizza il profilo di Luigi Ramaglia su LinkedIn, la più grande comunità professionale al mondo. ANSYS Acquires Assets Of Electronics Automated Design Analysis Leader DfR Solutions: ANSYS (NASDAQ: ANSS), the global leader and innovator of engineering simulation software, announced today that it has acquired substantially all the assets of DfR Solutions, the developer of Sherlock, the industry's only automated design reliability analysis software. Created using ANSYS 13. I'm new to ANSYS Fluent, so sorry if this is a basic question. of ATUCHA II NPP Reactor Pressure Vessel for Pressurized Thermal Shock Analysis, Nuclear Energy For New Europe 2008, Pages 702. • If can't avoid, frequently have to perform forced response analysis. Dimensions of the test cell and surrounding rooms were calculated using an AutoCAD file of building 9, provided by Facilities Management. Keywords: shock analysis, impulse analysis, dynamic response, finite element analysis (FEA), ansys workbench, shock experiment, deformation, impeller, acceleration, pulse width, 3d model. ANSYS Acquires Assets Of Electronics Automated Design Analysis Leader DfR Solutions Acquisition gives customers access to premium electronics reliability technology PR Newswire PITTSBURGH, May 1. Suppose there is a cantilever beam. The comparative study shows the optimum material to be used for the spring by proper analysis of the deflection and stresses of the helical spring. Intensive Care Medicine 2012; 38(1): 9-19 PubMedID. SAE J3168 describes a standardized approach to reliability physics analysis (RPA) that offers significant benefits to design and analysis of electronic hardware. [This article was first published in the May/June 2012 issue of The Connector. 1, Sherlock can be. 5 Professional NLS. Go to all ANSYS Learning Modules. Ansys 11 tutorial 1. In this analysis, maximum shear stress and total deformation is calculated using ANSYS software and the comparison is made on two material. In addition, we perform FEA for clients wishing to optimize designs for weight, cost and other parameters. A complete shock analysis of a dipole antenna structure subjected to underwater explosions is performed to foresee adverse effects of mechanical shock phenomena on the antenna structure. They are considering shock spectrum boundary condition for drop test simulation. Can be exported for current density, thermal, or structural analysis. Set Solution Controls; Solution > Analysis Type > Sol'n Controls The following window will pop up. Modal analysis is a. CFD NINJA | Computational Fluid Dynamics. This volume discusses the fundamental dynamic behavior of granular materials, in particular cohesionless sand, when subjected to shock and blast wave loading. To validate the strength of the design, structural analysis on major parts of the shock absorber is done using ANSYS WORKBENCH 14. Using this file and ANSYS computational grid generation module, generate properly clustered hybrid computational grid for the entire flow-field. SS Chouhan2 Prof. INTRODUCTION. beryllium copper. NOTE: I have never used DES, so my answer will be based on my knowledge of the topic, based on my experience with LES and RANS. 2 ansys Von-meses stress in catia 152Mpa and in ansys it is 149Mpa nearest values obtained. Field ditch effect. 8245 The weight vector 𝑤= 0 2 2 Check Mass Participation 𝑀𝑘= 𝑊𝑖𝜃𝑖𝑘 𝑖=1 2 𝑊𝑖(𝜃𝑖𝑘)2 𝑖=1 𝑀 𝑃𝑎𝑟𝑡𝑖𝑐𝑖 𝑎𝑡𝑖 = 𝑀𝑘 𝑘=1. This study used finite element analysis software ANSYS/LS-DYNA to perform a drop test simulation of test board under JESD22-B111 standard, with 0. Irwin Vigness of the U. ANSYS Acquires Assets Of Electronics Automated Design Analysis Leader DfR Solutions Acquisition gives customers access to premium electronics reliability technology PR Newswire PITTSBURGH, May 1. is the thin disk described in Example: Campbell Diagram Analysis (p. ANSYS virtually analyze how their products work in real world environment, at an early stage of product design. Modeling is done in CATIA and analysis is done in ANSYS. Lisa can be used for static, thermal, vibration, dynamic response, fluid, buckling, dc current, electromagnetic and acoustic analysis. ANSYS software shall be used to do the finite element analysis of the jaw crusher I INTRODUCTION Jaw crusher is a machine designed to reduce large solid particles of raw material into smaller particl Crushers are major size reduction equipment used in mechanical, metallurgical and allied industri They are available in various sizes and. INTRODUCTION. In this analysis, maximum shear stress and total deformation is calculated using ANSYS software and the comparison is made on two material. So Ansys provides a different kind of platforms for the different type of analysis. The contents of the book are mainly divided into three parts based on the type of loading imparted to the granular materials: Shock-wave loading (step pulse); Air-blast loading. Key Words: Shock Absorber, Automotive, CAD, FEA, ANSYS, spring. PRAKASH1*, K. Modeling is done in CATIA and analysis is done in ANSYS. 2 Saving and restoring jobs 40 2. Figure 1: Modal Analysis and Full Harmonic Analysis—No Link from Modal Solution. 2 “Study of the thermal behaviour of dry contacts in the brake discs « application of software ansys v11. Depend-ing on the type of analysis, it is necessary to choose the element type with. Fatigue Analysis in ANSYS | Fatigue Failure | HCF High Cycle & LCF Low Cycle Fatigue Life | GRS | - Duration: 29:01. 1 (193 ratings) Course Ratings are calculated from individual students’ ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately. The critical parts of the landing gear shock strut are inner metal tube as piston, cylinder and tapered rod assembly. Over 500,000 registered users across corporations, universities and government research labs worldwide, rely on Origin to import, graph, explore, analyze and interpret their data. Output controls are intended to allow users to write efficient results. com is a ~7 years old website dedicated to Finite Element Analysis beginner and advanced users, where unique tutorials, already solved FEA, books and webinars provide expertise and skills nowhere else to be found on the Internet but here. 9 Harmonic Analysis Used extensively by companies who produce rotating mach inery, ANSYS Harmon ic analysis is used to predict the sustained dynamic behavior of structures to consistent cyclic. Release 14. Confidence by Design ANSYS, Inc. Transient Analysis can be Thermal or Structural. ANSYS structural analysis software enables Supashock engineers to solve complex structural engineering problems and make better, faster design decisions. Just as in FEA analysis of stress and strain in mechanical structures, the finest mesh is required in the directions in an area or volume where conditions change most quickly. The dynamic response of the PCB, to a spectrum of shock pulses, is analyzed for rigid suspension designs. The Lagrangian FE solvers enable fast and efficient solutions when looking at structural components subjected to shock loading and large deformations. 0 to start a new ansys workbench session. Se mer: excel stock price feed, csv excel automatically, tradestation real time excel, macro open files time excel, part time excel work, coverting structural cfd ansys, cfd ansys fluent, cfd ansys fluent expert, ansys fluent cfd pdf, cfd analysis procedure ansys fluent pdf, cfd analysis process using ansys fluent, cfd ansys fluent simulation. beryllium copper. The analysis was performed to determine whether the structure will withstand the Tests performed. But as machines with. We have accomplished more than 7500 projects in Engg and Polytechnic colleges in last academic year we had 300 trained students and they were given job opportunities in multi-national companies specifically the best 25 research projects has been broadcasted in the world famous Tv channels and news. Browse the sections below to learn more. 02(2020), Article ID:99002,15 pages 10. Lávate las manos y cumple con las medidas de distanciamiento social. The peculiarity of using this program is the need to use large computer resources. However you need a response spectrum input for. Field ditch effect. Inertia relief analysis of a suspension shock linkage in Ansys 1. How can I simulate 1D problems in Ansys fluent? Shock tube is a tube of two regions containing fluids with different properties are separated by means of a diaphragm. SS Chouhan2 Prof. The Full Method and the Mode Superposition Method in Ansys are found to be great solution tools for shock loading conditions, including complex acceleration and force conditions. Help & Resources for Your Iris Smart Home. 1 Introduction to PRO-E Pro/ENGINEER is a parametric, feature based, solid modeling System. Typical industries and applications include: Aerospace, Automotive, Process Equipment, Pressure Vessels, Consumer Products, Medical Devices, HVAC, NVH, Thermo-Mechanical Fatigue, Shock and Impact, Conjugate Heat Transfer, Advanced Materials. Random Analysis To Perform a Random analysis to identify stress and amplitude levels in the geometry when subjected PSD based random input vibration in X , Y and Z - directions respectively. The structural response to the shock load is estimated by combined modal and response spectrum analyses. Transients are only for temperatures. In this analysis, maximum shear stress and total deformation is calculated using ANSYS software and the comparison is made on two material. This case study describes the structural analysis procedure for an electronics module developed for a space flight vehicle application. I am trying to model two specific shock waves in opposite directions in a length pipe. ANSYS workbench 16. Run the analysis in AUTODYN. Founded in 1970, ANSYS employs thousands of professionals, many of whom are expert M. [FREE] Ansys Transient Structural Tutorial Pdf Welcome to the M echanic al APDL In troductory Tutorials. Multi-point response spectrum. PREMALATHA, Assistant Professor Sana Engineering College Kodad [email protected] Generally, the shock should be compressed 40% - 50% of its travel at ride height. Carl Ollivier-Gooch of the University of British Columbia. shaping the terminal tail shock in the sonic boom pressure signature. CiteScore: 5. Join us for an informational overview of these key technologies to learn how Ansys solutions can help you develop the best electronics products possible. Tools used: ANSYS WB, KissSoft (bolt calculation). -level engineers in finite element analysis, computational fluid dynamics, electronics. com Commonly used in the analysis of: • Nuclear power plant buildings and components, for seismic loading • Airborne Electronic equipment for shock loading • Commercial buildings in earthquake zones Types of Response Spectrum analysis: Single-point response spectrum • A single response. 0 Ray Browell, ANSYS Inc. Enidine Inc. • static and modal analysis of Ford Taurus BIW 2000 accounted driver and passenger loads,constrained spring seats and front shock towers Tools used:Altair HyperMesh 13. Shock Analysis of On-board Equipment Submitted to Underwater Explosion. Shock response (ABAQUS/Explicit) 4. , which is entirely in English and with a 50/50 distribution between theory and practice. Questions are welcome during the live sessions. Did you know that you can get today's CFD Review headlines mailed to your inbox? Just log in and select Email Headlines Each Night on your User Preferences page. Ansys recommends a dedicated NVIDIA GPU card based on the Kepler, Maxwell or Pascal architecture (or newer) with at least 4GB of video RAM (8GB preferred). Hi Edo, I am a fairly new Ansys user so apologies for my limited knowledge. 3:Section model 50 mm element 30 Hz. sinusoidal vibration ansys, Principles of Vibration Analysis: Normal Modes to PSD to Direct Transient Date: 10/9/2014 Applied CAx / Predictive Engineering White Paper - Page Please share with your Friends 6 of 43 This is a beautifully simple relationship but it assumes that the stiffness of your structure stays constant or. PITTSBURGH, May 1, 2019 /PRNewswire/ -- ANSYS (NASDAQ: ANSS), the global leader and innovator of engineering simulation software, announced today that it has acquired substantially all the assets of DfR Solutions, the developer of Sherlock, the industry's only automated design reliability analysis software. The model is also changed by changing the thickness of the spring. • Constraint equations are linear combinations. What I want to simulate is a 10g 11ms sine impulse in the supports. Domain : Finite Element Analysis, Structural Analysis. This classification contains four classes of shock and shows good correlation with acidosis, blood product need and mortality. Import to and export from Ansys, Abaqus and/or Nastran. Modeling and Analysis is done using CATIA and ANSYS respectively. Numerical Analysis of Gun Barrel Pressure Blast Using Dynamic Mesh Adaption Sathish Xavier Follow this and additional works at: https://commons. • Conducted Ansys advance training on non-linear analysis; material and geometry non-linearity, geometry clean up and trouble shooting on problematic geometry. Shock Response Spectrum using ANSYS Workbench Shock Response Spectrum using ANSYS Workbench Tunalover (Mechanical) (OP) 1 Apr 10 09:52. 1/34 2011 ANSYS, Inc. Analysis Methods Used in TN-LC Transport Cask Analysis NCT • MP197HB Transport Cask Body • 3D ANSYS Model • Elastic/Equivalent Static Analysis • Lid Bolt • Evaluated based on NUREG-6007 methodology and criteria • Upper Trunnions • Evaluated for critical loads by hand calculations using ANSI N14. Hi, I'm trying to do a modal analysis (free vibration) of an assembly in Ansys Workbench 11. In this project a shock absorber will be designed and a 3D model which will be created is by using Pro/Engineer. • Mechanical Vibrations Analysis: Natural frequencies (Modal), Harmonics, Random Vibration – PSD, Shock loads (calculate stress, deformations, accelerations, transfer function). Finite element analysis (FEA) simulations are an integral part of the design process, whether it be a design change or a new product. Also directly evaluated thermal chamber test/vibration shaker one about the development products. a tension bar with one end surface fixed in all direction. Ansys recommends a dedicated NVIDIA GPU card based on the Kepler, Maxwell or Pascal architecture (or newer) with at least 4GB of video RAM (8GB preferred). Technical reports preparation. A 3D Assembly model of Splice Structure was created and analyzed for Various Tests: Shock Loading, Impact Loading (Equivalent Static Loading), Temperature Loading etc. Shock And Vibration Analysis Using Ansys Mechanical. ANSYS Acquires Assets Of Electronics Automated Design Analysis Leader DfR Solutions Acquisition gives customers access to premium electronics reliability technology PR Newswire PITTSBURGH, May 1. Nlgeom ansys. Ansys recommends a dedicated NVIDIA GPU card based on the Kepler, Maxwell or Pascal architecture (or newer) with at least 4GB of video RAM (8GB preferred). { "4bd44ac7-2462-45cf-96c9-32304df39a81": "/FileTypesContainer/FileType:GeometryFileType", "09afcaaa-9848-40aa-9f94-26a162aece66": "/FileTypesContainer/FileType. Students learn best writing skills with read of grademiners review those are written by qualified writers of world. outcomes, which is driven by the former, an FEM analysis has been done using the ANSYS Workbench, and the details are given in following section. 0 ℹ CiteScore: 2019: 5. 9 Harmonic Analysis Used extensively by companies who produce rotating mach inery, ANSYS Harmon ic analysis is used to predict the sustained dynamic behavior of structures to consistent cyclic. SHOCK ABSORBER AND ANALYSIS USING ANSYS SANGU NARESH M. Static and Transient Structural, Harmonic and Modal analysis systems. Founded in 1970, ANSYS employs thousands of professionals, many of whom are expert M. CALCULATION AND DESIGN OF SUPERSONIC NOZZLES FOR COLD GAS DYNAMIC SPRAYING USING MATLAB AND ANSYS FLUENT Jean-Baptiste Mulumba Mbuyamba A dissertation submitted to the Faculty of Engineering and the Built Envi-. Brainstormed concept designs with optimization, generated 3D solid modeling, made finite element models, and reviewed finite element solutions to. Displacement mode 1 and mode 2 from the modal analysis 𝜃1[𝑀𝑜 1]= 0 6. Look at latest prices, expert reviews, user ratings, latest news and full specifications for Samsung Galaxy Y. Upon completion of this course, participants will be able to setup, solve, and diagnose their own Shock and Vibration Analyses in Ansys Mechanical Workbench. When a vehicle is traveling on a. Hi everyone, I would like to run a transient analysis with half sine function. Rarely do I get a feeling of déjà vu in my professional life, but in March of this year something I was shown gave me a flashback to the 1980s. Finite Element Analysis is a numerical method of deconstructing a complex system into very small pieces (of user-designated size) called elements. Keywords: Shock Absorber, CATIA V5, ANSYS, FEA, Structural analysis. A classical shock impulse is created when the shock table changes direction abruptly. ANSYS Workbench Transient Structural Analysis Tutorial. 53: Load Step Options These SOLUTION commands are used to define options for individual load steps. Using this file and ANSYS computational grid generation module, generate properly clustered hybrid computational grid for the entire flow-field. o Modal Frequency analysis o Board bending o In circuit test (Static structural) o Mechanical shock (Transient dynamic) o Thermo-mechanical induced issues o Solder fatigue analysis o Stresses in vias during reflow o Warpage o This webinar concentrates on how Sherlock can accelerate the analysis capabilities of FEA solvers. Thanks in advance, Pedro. Several key points are summarized. The numerical engine may be the same as that used in the shock response spectrum calculation. Structural Engineer, Special Structures Black & Veatch Building a World of Difference Tel: 913-458-4651Radiation in ANSYS Fluent 10 61 4. TECH (Machine Design) Sana Engineering College, Kodad [email protected] Design and optimization of Francis turbine's stay-vanes and guide-vanes using CFD analysis with ANSYS CFX and Turbogrid 1301 with 24-hour thermal shock cycle. Detailed modal analysis determines the fundamental vibration mode shapes and corresponding frequencies. Key words: Shock Absorber, Bajaj Discover 150cc I. In this analysis, maximum shear stress and total deformation is calculated using ANSYS software and the comparison is made on two material. Release 14. At this stage a shock loading was considered, simulating the pass over a 20 mm obstacle on the road surface [5], [6]. We see the investment in finite element analysis services being repaid many times over in reduced development costs and a better product or quicker solution to your problem. pronounced effect on the shock spectra that an individual equipment may experience. By using preliminary results, initial structures were corrected in the way to gain added. Dynamic Concepts, Inc. Harmonic analysis done to assess the dynamic behaviour of the Gear Box and shock analysis is performed to analyse the shock response of the Gear Box under shock load. 3 Organization of files 41 2. CALCULATION AND DESIGN OF SUPERSONIC NOZZLES FOR COLD GAS DYNAMIC SPRAYING USING MATLAB AND ANSYS FLUENT Jean-Baptiste Mulumba Mbuyamba A dissertation submitted to the Faculty of Engineering and the Built Envi-. 294 𝜃2[𝑀𝑜 2]= 0 21. CiteScore: 5. Founded in 1970, ANSYS employs thousands of professionals, many of whom are expert M. Ansys shock analysis Ansys shock analysis. In this analysis, maximum shear stress and total deformation is calculated using ANSYS software and the comparison is made on two material. Through Finite Element Analysis (IL: Finite Element Analysis), we are able to help you to solve complex structural engineering challenges so as to allow you to make an informed and precise engineering design decision within a shorter period of time. The flow analysis of the system was done using commercially available CFD code FLUENT, integrated into ANSYS Workbench 15. MSI has more than \$2M invested in state-of-the-art design, analysis, and testing tools and techniques to understand root causes of problems. Sign-up for free online course on ANSYS simulations! Supersonic Flow Over a Wedge - Pre-Analysis & Start-Up static and total pressure behind the oblique shock. Hi In ANSYS Workbench (Static Structural) we can use horizontol and vertical accelerations due to a seismic event as seismic loads. pro-engineer. 0 CiteScore measures the average citations received per peer-reviewed document published in this title. ANSYS & Partner Webinars. Fatigue Analysis Using ANSYS Fatigue Module and ANSYS nCode DesignLife Confidence by Design ANSYS, Inc. Each of the FEA tests, Random Vibration, Harmonic Vibration, Mechanical Shock, and Natural Frequency, correspond to an analysis block within Ansys Workbench. Since their applicability was questioned, the aim of this study was to verify the validity of the new classification in multiple injured patients with traumatic brain injury. By ANSYS, Inc. The test cell and surrounding rooms were modeled using SolidWorks. , which is entirely in English and with a 50/50 distribution between theory and practice. Informazioni. • On site measurements to obtain inputs for analysis, • Developing methodology for furnace/boiler system evaluation, • Computational Fluid Dynamics (CFD) simulation of two-phase flow of fume-dust through the furnace/boiler unit focused on solving the problem of dust accumulation on the stokehole performed in ANSYS CFX,. Ansys recommends a dedicated NVIDIA GPU card based on the Kepler, Maxwell or Pascal architecture (or newer) with at least 4GB of video RAM (8GB preferred). The analysis performed dealt with the effect of a 50 mm high bump on the shock absorber performance when the vehicle is travelling at different speeds (3,10,25 and 40 km/hr). 1 Building a model 43 2. I am trying to perform the analysis on the shock tube to get the mach number of the shock wave. XThe Limit analysis provisions of ASME Code Section NG 3228. 2E-5) with the dimensions shown below is placed between two walls. FEA Analysis on Pressure Vessels for Cleanup of Radioactive Waste. ANSYS Hydrodynamics Analysis Training 12-Dec-2019 to (Shock) 05-Dec-2019 : 9am to Next Generation of Engineering Technology and Simulation with ANSYS, PTC 05. The analysis is done by considering load of bike weight, load of single person and load of two persons. I am under the impression that to perform a shock analysis you must perform a full transient analysis, SRS only works with a periodic input function. Keywords— Shock Absorber, Coil Spring, Stress analysis, ANSYS, Displacement, Stress. Ansys Sherlock Automated Design Analysis software is the only Reliability Physics/Physics of Failure (PoF)-based electronics design software that provides fast and accurate life predictions for electronic hardware at the component, board and system levels in early design stages. Pressurized Thermal Shock (PTS) has been identified as one of the most important industrial needs related to nuclear reactor safety. 1/34 © 2011 ANSYS, Inc. 9/29/2011 OUTLINE. PCB model details Basic guidelines for performing shock analysis based on Implicit Transient as well as Response spectrum in ANSYS WB is used A real life example of a PCB subjected to standard 30g-11ms-half sine shock is considered as the basis of the study. Technical reports preparation. In this effort, a detailed analysis of the thermal/shock response of beam windows is attempted of the ANSYS code. To validate the strength of the design, structural analysis on major parts of the shock absorber is done using ANSYS WORKBENCH 14. ATA engineers innovate to solve problems and can help implement new methods for test, analysis, and design in your organization. Harmonic analysis done to assess the dynamic behaviour of the Gear Box and shock analysis is performed to analyse the shock response of the Gear Box under shock load. Questions are welcome during the live sessions. Through Finite Element Analysis (IL: Finite Element Analysis), we are able to help you to solve complex structural engineering challenges so as to allow you to make an informed and precise engineering design decision within a shorter period of time. Skilled in finite elements analysis (Ansys, AQWA, Autodyn) with composite and metallic materials for. Constraint Equations. Key Words: Shock Absorber, Automotive, CAD, FEA, ANSYS, spring. ANSYS & Partner Webinars. From the aspect o. A Study Of Shock Analysis Using The Finite Element Method Verified With Euler-Bernoulli Beam Theory; Mechanical Effects Due To Pulse Width Variation Of Shock Inputs; And Evaluation Of Shock Response Of A Mixed Flow Fan David Jonathan González Campos For many engineers that use finite element analysis or FEA, it is very important to know how to properly model and obtain accurate solutions for. FEM analysis (FEMAP/NASTRAN) of satellite structures and components: quasi-static loads, random vibrations, shock response spectrum, sine-equivalent dynamics, thermoelastic loads. By observing the analysis results, the analyzed stress values are less than their respective yield stress values. ANSYS has acquired substantially all the assets of DfR Solutions, the developer of Sherlock, the industry’s only automated design reliability analysis software. ANSYS uses the finite-element method to solve the underlying governing equations and the associated problem-specific boundary conditions. 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Page 1 of 2 | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8256803750991821, "perplexity": 4387.459667991291}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-10/segments/1394678697956/warc/CC-MAIN-20140313024457-00039-ip-10-183-142-35.ec2.internal.warc.gz"} |
https://blender.stackexchange.com/questions/24848/how-to-transform-world-space-vertex-to-camera-space-position-in-cycles-osl | # How to transform world space vertex to camera space position in Cycles OSL
I used blender as CG generation tool for Computer Vision research. I tried to render depth (z) value of each surface instead of its color. So I make simple shader, like this
shader depth_shader(
vector Position = vector(1,0,0),
output closure color Color = emission())
{
vector lp = transform("world","camera",Position);
Color= color(lp[2], lp[2], lp[2]) * emission();
}
"Position" is input from Geometry node. But when I tried this, It returns odd results, and some pixel has negative value. How to get camera space position, which only applied by rotation, scale and translation? (Before projection matrix multiplication)
• you can use P which is already defined and it is the position in world coordinates, i think that Z has to be negative if you look at the local axis of the camera in the 3D view – Chebhou Feb 16 '15 at 10:23
for transforming the position you should use point type because according to the OSL Language Specs :
Depending on the type of the passed point p, different transformation semantics will be used. A point will transform as a position, a vector as a direction without regard to positioning
just change the type of the Position variable to point or use the P variable that holds the current position then use the transform function as you did ; even after that the whole objects will be bright white, so i have tried to normalize the Z coordinate using two variables which act as near and far planes that limits the depth range :
shader depth_shader(
float minZ = 0,
float maxZ = 1,
output closure color Color = emission())
{
point lP = transform("camera", P);
float Z = lP[2];
if( (Z>minZ) && (Z<maxZ))
Z = (Z-minZ)/(maxZ-minZ);
else
Z = 0;
Color= color(Z, Z, Z) * emission();
}
• Oh, point! Thanks for reply. After changing vector to point, my shader works well! – Kichang Kim Feb 19 '15 at 10:31
• oops, when I set camera position to (0,0,2) and make plane to (0,0,0) which facing camera, depths is not 2.(I removed normalization term of your code, directly set lP[2] to output). It seems be not pure depth from camera. Is blender camera space that someting normalized space like view frustrum? – Kichang Kim Feb 21 '15 at 2:32
• @KichangKim i think it should be 2, here is how to test it connect the z depth to "greater than" math node then to emission node and change the value "in math node" to see the clipping, AFAIK camera space is is just a rotated & translated version of world space in which the camera is the origin – Chebhou Feb 21 '15 at 10:18
• I recheck my code and scene, found small errors :( now, all of results are correct, very thanks! – Kichang Kim Feb 24 '15 at 6:36 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.20976994931697845, "perplexity": 2686.2768252619717}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178381989.92/warc/CC-MAIN-20210308052217-20210308082217-00418.warc.gz"} |
https://phys.libretexts.org/Bookshelves/Astronomy_and_Cosmology_TextMaps/Map%3A_Stellar_Atmospheres_(Tatum)/7%3A_Atomic_Spectroscopy/7.19%3A_Isotope_effects | $$\require{cancel}$$
The effect of different isotopic masses is to displace the centre of mass between nucleus and electrons a small amount. In the hydrogen atom, for example, the term values (neglecting fine structure and referring to the Bohr model) are given by equation 7.4.9, in which the expression for the Rydberg constant includes the reduced mass $$\mu = \frac{Mm}{M+m}$$ of the electron. It becomes a simple matter to calculate the energy levels and Balmer wavelengths of $$\text{D}, \ \text{He}^+ , \ \text{Li}^{++}$$, etc., merely by exchanging the reduced mass in $$\text{H}$$ by the reduced mass in the other species. I commend this exercise to the reader. For example, by how much does the wavelength of Hα differ in the spectra of ordinary hydrogen and deuterium? For more complex atoms, the calculation of the isotope shift is more difficult, but the basic reason for the shift is the same.
It might well be thought that isotope shifts would be greatest for very light atoms, but would be negligible for heavier atoms, because the displacement of the position of the centres of mass in different isotopes of a heavy atoms such as, for example, iron, would be negligible. This is indeed the case for the mass isotope effect. It comes as something of a surprise, therefore, to learn that there are significant isotope shifts between isotopes of quite massive isotopes, such as lead, cadmium, gold, mercury, promethium and osmium, and that such shifts have even been observed in stellar spectra. The shift is a result of the relatively large volumes of these nuclei. There is no need to go into the detailed theory of the volume effect here, though it is at least useful to know of its existence and, to some extent, its cause. An allowed electric dipole line always involves a transition between two levels belonging to different configurations, and the volume effect is most marked for those transitions in which the two configurations have different numbers of $$s$$-electrons. These are electrons with zero orbital spin angular momentum, and, in the Bohr-Sommerfeld atomic model (mentioned briefly in section 7.4), these orbits would be ellipses that have degenerated into straight lines through the nucleus. In other words, we can understand that the volume effect is related to the penetration of the nuclei by $$s$$-electrons, and we can see why the effect is most marked in the largest nuclei. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9149203300476074, "perplexity": 391.1348633577199}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-35/segments/1566027331485.43/warc/CC-MAIN-20190826085356-20190826111356-00350.warc.gz"} |
http://networkdata.schochastics.net/reference/covert_27.html | These are two datasets about a set of terrorists and the attacks they carry out collected by the MIND Lab at University of Maryland (UMD) (http://www.mindswap.org/). NETWORK 1-mode matrix 645 x 645 organization by organization, directed ties. Ties are co-location of terrorist attacks. 1-mode matrix 260 x 260 organization by organization, directed ties. Ties are co-located terrorist attacks by same organisation.
covert_27
## Format
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http://mathematica.stackexchange.com/questions/22982/is-it-possible-for-me-to-explicitly-specify-a-point-list-for-spatialgraphdistrib | # Is it possible for me to explicitly specify a point list for SpatialGraphDistribution?
The function RandomGraph[SpatialGraphDistribution[n, r]] generates a random geometric graph over $[0,1]^2$ where vertices are connected if they are within a distance $r$ of one-another.
How would I explicitly specify a list of points for generating a random geometric graph using this function? Specifically, I need to enforce a minimum threshold distance between points.
Clarification: My point list is going to come from a Random Sequential Adsorption (RSA) simulation of circles on a plane. So I mean that no two points should be closer than some minimum threshold distance set by the radius of the circles being deposited, not that two points shouldn't share an edge if they are closer than the threshold distance.
-
After reading the clarification, I'm not sure I understand what you're asking. Is this what you need? – Szabolcs Apr 9 '13 at 14:33
@Szabolcs Oh, no I'm just asking to be able to feed a set of points to SpatialGraphDistribution that I've already generated by simulating Random Sequential Adsorption (RSA). My understanding, from the literature, is that this random packing process must be simulated. – M.Y. Apr 10 '13 at 2:16
@Szabolcs I think you're answer is the answer I was looking for - it can't be done, so I have to rely on my own implementation. – M.Y. Apr 10 '13 at 2:16
With SpatialGraphDistribution it's not possible, as this is used for representing a distribution. You were asking, "How would I explicitly specify a list of points for generating a random geometric graph", but if you give a set of points, then the graph is not random any more, so SpatialGraphDistribution won't be of use.
I would proceed like this:
Take a set of points (you'll already have this list from another source):
pts = RandomReal[1, {100, 2}];
distances =
With[{tr = Transpose[pts]},
Function[point, Sqrt[Total[(point - tr)^2]]] /@ pts];
Build an adjacency matrix, taking care not to connect each node to itself:
am = UnitStep[r - distances] - IdentityMatrix@Length[pts];
Convert it to a graph:
AdjacencyGraph[am, VertexCoordinates -> pts]
- | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.38275066018104553, "perplexity": 685.4704889247434}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-52/segments/1418802767843.95/warc/CC-MAIN-20141217075247-00069-ip-10-231-17-201.ec2.internal.warc.gz"} |
https://calogica.com/sql/snowflake/dbt/2019/09/09/snowflake-backup-s3.html | # How to Backup Snowflake Data to S3 or GCS
In this post, we take a look at how to back up data in your Snowflake account to an external S3 or external GCS location.
Snowflake has amazing built-in backup functionality, called Time Travel that lets you access data as of a certain date. In addition, Snowflake protects your data in the event of a system failure or other catastrophic event with its Fail-safe feature which allows Snowflake support to restore data for you during the Fail-safe window.
In addition, Snowflake has a near magical ability to undrop objects that were dropped, which is a direct result of its immutable architecture.
However, Time Travel is limited to 1 day for Standard Edition (up to 90 days for Enterprise Edition), while Fail-safe adds 7 days of peace of mind. So, while both Time Travel and Fail-safe are convenient and storage-efficient means of backing up your data, some Snowflake customers, especially those using Standard Edition, may want to back up their data using alternate means.
One easy way is to simply unload your data to an object storage location, using Snowflake’s built-in copy into command. Let’s explore how to automate this using everyone’s favorite data transformation library dbt for a number of databases and schemas. (See more on dbt here.)
## External Stages
Snowflake can access external (i.e. in your AWS/GCP account, and not within Snowflake’s AWS/GCP environment) S3/GCS buckets for both read and write operations. The easiest way to take advantage of that is to create an external stage in Snowflake to encapsulate a few things. (We’ve used stages in a previous post on loading data using Snowpipes.)
### Create S3 Stage
Let’s create a dedicated stage for our backups:
create or replace stage backup_stage url='s3://my_s3_bucket/snowflake_backup'
credentials=(aws_key_id='<AWS_KEY_ID>', aws_secret_key='<AWS_SECRET_KEY>')
file_format=(type=csv compression='GZIP' field_optionally_enclosed_by='"', skip_header=1)
• Note that we’re specifying the csv file format, along with gzip compression as part of the stage definition. Your business case will vary here, and parquet or other format types may be better choices for you.
• The skip_header option here only applies to reading data from this stage, not to unloading data. We *will specify during our unload process that we want to save table headers with our backups. However, for restore purposes, we want to skip headers. You can leave this option out if you’d rather get the relevant table headers back as the first row when you read from this external stages later.
You can view more information on the stage you just created by running:
desc stage backup_stage;
Pay attention to the database and schema in which you create the stage. The fully qualified name for the external stage will be <database>.<schema>.backup_stage. Also consider the roles which will be copying data to or from the stage. You can view the grants on the stage with:
show grants on stage backup_stage;
The only privilege you’ll need to worry about is USAGE.
grant usage on stage backup_stage to role your_role;
Find more information on creating stages here.
### Create GCS Stage
This assumes that you have a Storage Integration already configured for GCS. We can use the same format as for S3:
create or replace stage backup_stage url='gcs://my_gc_bucket/snowflake_backup'
storage_integration = YOUR_GCS_INTEGRATION
file_format=(type=csv compression="GZIP", field_optionally_enclosed_by='"', skip_header=1);
All of the details for the S3 stage creation are also relevant to the GCS stage.
Find more information on setting up your own integation here and on setting up a GCS stage here.
### Copy into Stage
We can now copy into our external stage from any Snowflake table. This works for either S3 or GCS:
copy into @<your_database>.<your_schema>.backup_stage/my_database/my_schema/my_table/data_
from my_database.my_schema.my_table
overwrite = true
max_file_size = 104857600
Let’s quickly talk about what’s going on here:
• We are referencing the fully qualified name of the stage like we would with a table.
• We are copying from a table into our external stage, which uses the compressed format specified earlier.
• By naming the output file data_, with no other related options, we specify that we want Snowflake to create multiple files, all starting with data_*, which allows Snowflake to run this command in parallel in our virtual warehouse (parallel runs are limited by the size of the virtual warehouse).
• We want the exported files to include table headers
• We’re overwriting any existing files at that location
• We specified an upper limit of 100MB per file (100*1,024^2 = 104,857,600 bytes) (See Snowflake’s General File Sizing Recommendations for more.)
There are many more options to be explored, see the copy into docs for help.
## Automation via dbt
So, this helped backing up one table. However, we likely have dozens or hundreds more, across various schemas and databases. Thankfully, dbt allows us to script generation of SQL commands using jinja2
What we really want is a flexible macro that will build the copy into command for a given database/schema/table combination.
For example:
{% macro get_backup_table_command(table, day_of_month) %}
{% set backup_key -%}
day_{{ day_of_month }}/{{ table.database.lower() }}/{{ table.schema.lower() }}/{{ table.name.lower() }}/data_
{%- endset %}
copy into @<your_database>.<your_schema>.backup_stage/{{ backup_key }}
from {{ table.database }}.{{ table.schema }}."{{ table.name.upper() }}"
overwrite = true
max_file_size = 1073741824;
{% endmacro %}
In this case, we’re creating the copy into statement that will back up our given table into an object store key that looks something like this:
[gcs|s3]://my_bucket/snowflake_backup/day_09/dw/shop/dim_product/
(We’re upper-casing the table name in quotes in the from clause to guard against reserved words in table names, e.g. such as “ORDER” in the case of Fivetran-sourced Shopify data. 😒)
Using this macro, we could loop through a list of database, schemas and tables and execute backup statements like this in sequence.
Let’s see how that would look in a dbt macro.
• The key components here is the backups dictionary that specifies a list of schemas for each database key. In this example, we’re backing up 2 databases ("RAW" and "DW") with several schemas in each.
• In this case we’re looking to backup all tables in each specified schema, so we’re using the handy get_tables_by_prefix macro from the dbt_utils package to get a list of relations (i.e. tables) that match our filter. Note that we can exclude tables as well, such as any metadata tables (excluding anything starting with FIVETRAN_%).
• In this example, we chose to keep up to 31 days of backups, one for each day of the month. Once the month is over, we simply roll over and start overwriting backups. This is a very simple backup scheme, so please make sure this modify this suit your business needs. This is just meant to illustrate that we have access to some of Python’s date formatting functionality via Jinja to create SQL statements.
• Since we ultimately want to operationalize this backup process using a dbt run-operation, we wrap our code in a statement which allows us to use a run-operation to execute SQL that does not exclude a select statement.
{% macro backup_to_object_store() %}
{%- call statement('backup', fetch_result=true, auto_begin=true) -%}
{% set backups =
{
"RAW":
["APP_DATA",
"SHOPIFY",
"ZENDESK"],
"DW":
["CUSTOMER",
"SHOP",
"FINANCE"]
}
%}
{% set day_of_month = run_started_at.strftime("%d") %}
{{ log('Backing up for Day ' ~ day_of_month, info = true) }}
{% for database, schemas in backups.items() %}
{% for schema in schemas %}
{{ log('Getting tables in schema ' ~ schema ~ '...', info = true) }}
{% set tables = dbt_utils.get_tables_by_prefix(schema.upper(), '', exclude='FIVETRAN_%', database=database) %}
{% for table in tables %}
{{ log('Backing up ' ~ table.name ~ '...', info = true) }}
{% set backup_table_command = get_backup_table_command(table, day_of_month) %}
{{ backup_table_command }}
{% endfor %}
{% endfor %}
{% endfor %}
{%- endcall -%}
{%- endmacro -%}
We can then call this from the command line like so,
dbt run-operation backup_to_object_store
which we can then automate in our CI/CD environment of choice, such as dbt Cloud or Gitlab.
## Data Recovery
So, how do we use these backup files if we want to recover data from a previous backup? A great thing about Snowflake external stages is that we can simply read from them, using the same stage definition we’ve used for unloading data to them. For example, we could pick a specific table (my_table) and day (day_09), and read from the backed up data like so:
select
$1 as id, to_timestamp($2, 'yyyy-mm-dd hh24:mi:ss.ff Z') as ts
from
@<your_database>.<your_schema>backup_stage/day_09/my_db/my_schema/my_table/
Which would result in output like this:
| ID | TS |
|---------|-------------------------------|
| 9147485 | 2019-10-09 15:06:43.627000000 |
| 9147484 | 2019-10-09 15:06:36.230000000 |
| 9147483 | 2019-10-09 15:06:28.263000000 |
| 9147482 | 2019-10-09 15:06:09.158000000 |
| 9147481 | 2019-10-09 15:06:02.582000000 |
Consequently, we can create a table in Snowflake with the recovered data:
create table my_table_recovered as (
select
$1 as id, to_timestamp($2, 'yyyy-mm-dd hh24:mi:ss.ff Z') as ts
from
@<your_database>.<your_schema>backup_stage/day_09/my_db/my_schema/my_table/
)
If we’re happy with the recovered data, we can then swap the recovered data with the current (“bad”) data,
alter table my_table rename to my_table_bad;
alter table my_table_recovered rename to my_table;
Then at a future point, we could delete the “bad” table:
drop table my_table_bad;
Hopefully, this gave you some idea of how to extend the built-in Snowflake recovery features like Time Travel and Fail-safe with a few alternatives.
As always, please let me know if you have any feedback or comments!
Updated: | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.24655087292194366, "perplexity": 5660.595363583094}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-50/segments/1606141176049.8/warc/CC-MAIN-20201124082900-20201124112900-00112.warc.gz"} |
https://ashpublications.org/blood/article/136/Supplement%201/3/473882/Study-of-Low-Dose-Ibrutinib-Use-in-a-Community | Background:
Ibrutinib, a small molecule inhibitor of Bruton's Tyrosine Kinase (BTK) is approved for use in a variety of lymphomas. Priced at 130,000/year, Ibrutinib imposes a significant financial burden on patients and society[1]. The study serving as the basis for the currently approved dose [2] demonstrated >95% BTK receptor occupancy at a dose of 2.5 mg/kg. Data suggests that lower doses of Ibrutinib are equally effective[3] and dose reductions[4, 5] do not compromise outcome. Objective: To evaluate patient outcomes and cost savings with clinically indicated low dose (LD) of Ibrutinib in a community practice in hematological malignancies. Method: All patients treated with standard and LD Ibrutinib between January 2014 and July 2020 were identified. Reason for dose modification and best responses were abstracted. Patients with inadequate follow up or less than a week of treatment were excluded from the analysis. Responses were defined based on the iwCLL response criteria for Chronic Lymphocytic Leukemia (CLL), Lugano criteria for Non-Hodgkin's Lymphoma and International Working Group on Waldenström's Macroglobulinemia (WM), as applicable. To calculate drug cost at lower doses of Ibrutinib, cumulative number of patient-months on different dose levels of ibrutinib was calculated by adding the number of months each patient had remained at the dose level at the time of data cut-off. Drug cost at LD was calculated by multiplying monthly wholesale acquisition price for different dose levels of ibrutinib by the cumulative number of patient-months at that dose level. Cost differential between actual drug cost and projected drug cost at full dose was calculated. Results: 98 patients were identified. 10 were excluded from the analysis based on drug not started (3), inadequate follow-up (3), other (4). Median length of follow up for all patients was 20 months (4-70 months) and on LD Ibrutinib 12.5 months (1-60 months). 10 and 12 patients received 140 mg and 280 mg of Ibrutinib respectively due to side effects. 61 patients had CLL, 9 WM, 15 mantle cell lymphoma (MCL), and 2 marginal zone lymphoma (MZL). Response rates were similar across diagnoses and dose levels (TABLE 1 and FIGURE 1). Progressive disease (PD) at low dose was seen in 2 CLL patients with complex cytogenetics, deletion 17p and extensive prior therapy. The one WM patient with PD had been extensively pretreated. Cumulative patient-months at the 140 mg and 280 mg dose levels of Ibrutinib was 177 and 123 months respectively. Drug cost for the 140 mg and 280 mg Ibrutinib cohorts were712,276 and $989,943 respectively, for a total cost of$1,702,219. Potential drug cost for the 420 or 560 mg dose of Ibrutinib for the same duration of therapy was $3,621,828. Cumulative cost avoidance on LD Ibrutinib was$1,919, 608.
Conclusions:
Clinically indicated low dose Ibrutinib was equally effective and produced significant cost savings.
References:
1. Qiushi Chen, N.J., Turgay Ayer, William G. Wierda, Christopher R. Flowers, Susan M. O'Brien, Michael J. Keating, Hagop M. Kantarjian, and Jagpreet Chhatwal, Economic Burden of Chronic Lymphocytic Leukemia in the Era of Oral Targeted Therapies in the United States. Journal of Clinical Oncology, 2017: p. 166-174.
2. Ranjana H. Advani, J.J.B., Jeff P. Sharman , Sonali M. Smith , Thomas E. Boyd , Barbara GrantKathryn S. Kolibaba , Richard R. Furman , Sara Rodriguez , Betty Y. Chang , Juthamas Sukbuntherng , Raquel Izumi , Ahmed Hamdy , Eric Hedrick , Nathan, Bruton Tyrosine Kinase Inhibitor Ibrutinib (PCI-32765) Has Significant Activity in Patients With Relapsed/Refractory B-Cell Malignancies. Journal of Clinical Oncology, 2013: p. 88-94.
3. Lisa S. Chen, P.B., Nichole D. Cruz , Yongying Jiang , Qi Wu , Philip A. Thompson , Shuju Feng , Michael H. Kroll , Wei Qiao , Xuelin Huang , Nitin Jain , William G. Wierda , Michael J. Keating , Varsha Gandhi, A pilot study of lower doses of ibrutinib in patients with chronic lymphocytic leukemia. Blood, 2018: p. 2249-2259.
4. Lad DP, Malhotra P, Khadwal A, Prakash G, Jain A, Varma S. Reduced Dose Ibrutinib Due to Financial Toxicity in CLL. Indian Journal of Hematology and Blood Transfusion, 2018. 35(2): p. 260-264.
5. Othman S. Akhtar, K.A., Ian Lund, Ryan Hare, Francisco J. Hernandez-Ilizaliturri & Pallawi Torka, Dose reductions in ibrutinib therapy are not associated with inferior outcomes in patients with chronic lymphocytic leukemia (CLL). Leukemia & Lymphoma, 2019. 60(7): p. 1650-1655.
Disclosures
No relevant conflicts of interest to declare.
OffLabel Disclosure:
Ibrutinib is approved at a dose of 420 mg orally daily or 560 mg orally daily in different lymphoproliferative disorders.
## Author notes
*
Asterisk with author names denotes non-ASH members. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3853588104248047, "perplexity": 25941.86595120923}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-21/segments/1620243988953.13/warc/CC-MAIN-20210509002206-20210509032206-00213.warc.gz"} |
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It is currently 21 May 2013, 23:03
# Ms. Morris invested in Fund A and Fund B. The total amount
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Ms. Morris invested in Fund A and Fund B. The total amount [#permalink] 26 Oct 2012, 14:02
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Question Stats:
66% (03:59) correct 33% (02:12) wrong based on 17 sessions
Ms. Morris invested in Fund A and Fund B. The total amount she invested, in both funds combined, was $100,000. In one year, Fund A paid 23% and Fund B paid 17%. The interest earned in Fund B was exactly$200 greater than the interest earned in Fund A. How much did Ms. Morris invest in Fund A?
(A) $32,000 (B)$36,000
(C) $40,000 (D)$42,000
(E) $45,000 For this question, one could do an algebraic solution, but would it be faster to backsolve from the answers? I would argue for the latter, though I imagine there will be a difference of opinions on this question. My argument, along with a discussion of backsolving in general and a complete solution to this problem, is here: http://magoosh.com/gmat/2012/gmat-plugg ... -choice-c/ Perhaps other experts would also like to chime in on the issue of when to solve algebraically vs. when to backsolve. Mike [Reveal] Spoiler: OA _________________ Mike McGarry Magoosh Test Prep Last edited by mikemcgarry on 26 Oct 2012, 16:28, edited 1 time in total. Kaplan Promo Code Knewton GMAT Discount Codes Veritas Prep GMAT Discount Codes Director Joined: 22 Mar 2011 Posts: 608 WE: Science (Education) Followers: 43 Kudos [?]: 267 [1] , given: 43 Re: backsolving [#permalink] 26 Oct 2012, 15:42 1 This post received KUDOS mikemcgarry wrote: Ms. Morris invested in Fund A and Fund B. The total amount she invested, in both funds combined, was$100,000. In one year, Fund A paid 23% and Fund B paid 17%. The interest earned in Fund B was exactly $200 greater than the interest earned in Fund A. How much did Ms. Morris invest in Fund A? (A)$32,000
(B) $36,000 (C)$40,000
(D) $44,000 (E)$45,000
For this question, one could do an algebraic solution, but would it be faster to backsolve from the answers? I would argue for the latter, though I imagine there will be a difference of opinions on this question.
My argument, along with a discussion of backsolving in general and a complete solution to this problem, is here:
http://magoosh.com/gmat/2012/gmat-plugg ... -choice-c/
Perhaps other experts would also like to chime in on the issue of when to solve algebraically vs. when to backsolve.
Mike
The correct answer should be 42,000, and it is not listed neither above, nor in the question you published on your blog.
It just appears in the solution you posted.
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Re: backsolving [#permalink] 26 Oct 2012, 16:30
EvaJager wrote:
The correct answer should be 42,000, and it is not listed neither above, nor in the question you published on your blog.
It just appears in the solution you posted.
Yes, you're right --- a mistake on my part --- the OA is \$42,000, and I just corrected the question above & the blog. Thank you very much.
Mike
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Re: Ms. Morris invested in Fund A and Fund B. The total amount [#permalink] 16 Nov 2012, 13:07
Could someone post the algebraic way please
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Re: Ms. Morris invested in Fund A and Fund B. The total amount [#permalink] 16 Nov 2012, 14:07
chibimoon wrote:
Could someone post the algebraic way please
A+B=100k
0.17B=0.23A+200=> -23A+17B=20000
from first equation 23A+23B=2300K
40B=2320K
B=58K
A=100k-58k=42k
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Re: Ms. Morris invested in Fund A and Fund B. The total amount [#permalink] 02 Feb 2013, 16:35
1
KUDOS
chibimoon wrote:
Could someone post the algebraic way please
A+B=100,000
0.17B=0.23A+200
You now have two equations, so you can either substitute or eliminate. In the explanation above, elimination is used, here I use substitution (elimination is easier in this case)
Take away decimals first: 17B=23A+20,000
Isolate first equation to solve for A (your goal): B=100,000-A
Plug in for B:
17(100,000-A)=23A+20,000
1,700,000-17A=23A+20,000
1,680,000=40A
1,680,000/40=A
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Re: Ms. Morris invested in Fund A and Fund B. The total amount [#permalink] 02 May 2013, 11:29
Here's another problem from that same article, one that's even less amenable to algebraic treatment.
If the sequence a(n) is defined as a(n) = n^2 + n + \sqrt{n+3}, then which of the following values of n represents the first terms such that a(n) > 500?
(A) 13
(B) 22
(C) 33
(D) 46
(E) 78
[Reveal] Spoiler:
OA = (B)
A full solution is shown at that that article:
http://magoosh.com/gmat/2012/gmat-plugg ... -choice-c/
Mike
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Re: Ms. Morris invested in Fund A and Fund B. The total amount [#permalink] 02 May 2013, 11:29
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Display posts from previous: Sort by | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4114341139793396, "perplexity": 10060.716181473786}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368701409268/warc/CC-MAIN-20130516105009-00024-ip-10-60-113-184.ec2.internal.warc.gz"} |
http://www.open-source-projects.net/libSDL2_gfxutils/Documentation/Online/SDL2_gfxutils_documentation/html/SDL2_gfxutils_Forms_generating_utils.html | # Forms generating functions¶
## Polygons¶
Parameters:
• sides (uint32_t) – The number of sides of the polygon to generate.
• center (Pixel) – The wants center of the polygon.
• orientation (float) – An offset in degrees to add to influence the incline of the polygon.
Return type:
Polygon *
Returns:
A regular convex polygon .
note: This result in a regular polygon with sides sides with radius length radius starting at orientation. A blue 12 sides polygon convex. An polygon is convex if all vertex from the polygon are on the same side from every edge of the polygon.
Polygon *generate_corners_rounded_polygon(uint32_t sides, float radius, Pixel center, float orientation)
Parameters: sides (uint32_t) – The number of sides of the polygon to generate. radius (float) – The radius of the polygon to generate. center (Pixel) – The wanted center of the polygon. orientation (float) – An offset in degrees to add to influence the incline of the polygon. Polygon * A polygon which corners are arcs which size is in relationship to the number of sides of the polygon. The radius goes from the center to the center of the circle arcs: the rounded corners.
Polygon *generate_sides_rounded_polygon(uint32_t sides, float radius, Pixel center, float orientation)
Parameters: sides (uint32_t) – The number of sides of the polygon to generate. radius (float) – The radius of the polygon to generate. center (Pixel) – The wanted center of the polygon. orientation (float) – An offset in degrees to add to influence the incline of the polygon. Polygon * A polygon which sides are rounded according the number of sides of the polygon. The radius goes from the center to the center of the circle arcs. Warning The parameter sides must be conform to: sides % 2 != 0 I can only generate odd sides numbered sides rounded polygons.
Polygon *generate_rounded_inside_out_polygon(uint32_t sides, float radius, Pixel center, float orientation)
Parameters: sides (uint32_t) – The number of arcs of the polygon to generate. radius (float) – The radius of the polygon to generate. center (Pixel) – The wanted center of the polygon. orientation (float) – An offset in degrees to add to influence the incline of the polygon. Polygon * A polygon alternating inside nad outside arcs the number of sides of the polygon. The radius goes from the center to the center of the circle arcs. Warning The sides number is multiply per 2 to obtains an even numbered polygon.
Polygon *generate_alternate_inside_half_circle_polygon(uint32_t sides, float radius, Pixel center, float orientation)
Parameters: sides (uint32_t) – The number of sides of the polygon to generate. radius (float) – The radius of the polygon to generate. center (Pixel) – The wanted center of the polygon. orientation (float) – An offset in degrees to add to influence the incline of the polygon. Polygon * A rounded polygon alternating arcs rounded to the outside and to the inside of the polygon. The radius goes from the center to the center of the circle arcs. Warning The result is an even polygon of the double of the sides values.
Polygon *generate_alternate_outside_half_circle_polygon(uint32_t sides, float radius, Pixel center, float orientation, bool side_arcs)
Parameters: sides (uint32_t) – The number of sides of the polygon to generate. radius (float) – The radius of the polygon to generate. center (Pixel) – The wanted center of the polygon. orientation (float) – An offset in degrees to add to influence the incline of the polygon. sides_arcs (bool) – Boolean value determine if the sides which are not half-cirlce arcs should be rounded. Polygon * A polygon with half-circle rounded to the inside from the half sum from the sides of the polygon and the other is even an arc or an straight line according to the side_arcs boolean value. The radius goes from the center to the center of the circle arcs. Warning The result is an even polygon of the double of the sides values.
## Stars¶
Star *generate_star(uint32_t pikes, float radius, Pixel center, float orientation)
Parameters:
• pikes (uint32_t) – The number of pikes of the star.
• radius (float) – The radius of the star base polygon not the spike.
• center (Pixel) – The wants center from the star.
• orientation (float) – An offset in degrees to add to influence the incline of the star.
Return type:
Star *
Returns:
A star with the number of wants pikes according to the given settings.
note: This function generate a star based on a regular polygon. A blue 24 peaks star.
Note:
Star *generate_pentagram_star(float radius, Pixel center, float orientation)
Parameters:
• radius (float) – An base value for the generation of the 5 pikes star.
• center (Pixel) – The wants center from the 5 pikes star.
• orientation (float) – An offset in degrees to add to influence the incline of the star.
Return type:
Star *
Returns:
A not a regular 5 pikes star but a pentagram star or pentacle.
note: This function generate a simply 5 extremity star with the particularity that the resulting star is not a regular star but a pentagram star. A blue pentagram star.
Note:
Star *generate_hexagram_star(float radius, Pixel center, float orientation)
Parameters:
• radius (float) – An base value for the generation of the 6 pikes star.
• center (Pixel) – The wants center from the 6 pikes star.
• orientation (float) – An offset in degrees to add to influence the incline of the star.
Return type:
Star *
Returns:
A not a regular 6 pikes star but a hexagram star or star of David.
note: This function generate a simply 6 extremity star, with the particularity that the resulting star is not a regular star but an hexagram star or star of David. A blue hexagram star.
Note:
## pentagram¶
Pentagram *generate_pentagram(float radius, Pixel center, float orientation)
Parameters:
• radius (float) – An base value for the generation of the 5 pikes star.
• center (Pixel) – The wants center from the 5 pikes star.
• orientation (float) – An offset in degrees to add to influence the incline of the star.
Return type:
Pentagram *
Returns:
A pentagram or named pentacle.
note: This function generate an 5 extremity star with an centered pentagon from which every vertex go to the center. A blue pentagram.
Note:
## hexagram¶
Hexagram *generate_hexagram(float radius, Pixel center, float orientation)
Parameters:
• radius (float) – An base value for the generation of the 6 pikes star.
• center (Pixel) – The wants center from the 6 pikes star.
• orientation (float) – An offset in degrees to add to influence the incline of the star.
Return type:
Hexagram *
Returns:
A hexagram.
note: This function generate a 6 extremity star with an centered hexagon from which every vertex go to the center. A blue hexagram.
Note:
## Fractal¶
Polygon *generate_fractal(uint32_t polygon, float radius, Pixel center, float orientation, bool open)
Parameters: polygon (uint32_t) – Base polygon from the fractal. radius (float) – The radius from the base polygon. center (Pixel) – The wants center from the fractal. orientation (float) – An offset in degrees to add to influence the incline of the fractal. open (bool) – Change the fractal pikes. Polygon * A strange fractal form coming from an crazy brain. :) The radius goes from the center to the farest point of the fratcal (so equal to the real_length value) .
## Spiral¶
Spiral *generate_simple_spiral(Pixel center, uint32_t turns, uint32_t base, float offset_exponent, float orientation, bool reverse)
Parameters:
• center (Pixel) – The center from the spiral.
• turns (uint32_t) – The number of revolution of the spiral.
• base (uint32_t) – the base number of points to make one turn (roundness).
• offset_exponent (float) – The factor to compute the distance between 2 points a turn offset.
• orientation (float) – An offset in degrees to add to influence the incline of the spiral.
• reverse (bool) – Reverse the spiral.
Return type:
Spiral *
Returns:
A spiral according to the given settings.
Note:
The radius goes from the center to the end of the first entire revolution of the spiral.
Note
The base and the offset_exponent parameters values will influente of the size of the spiral.
You cannot set an radius but the generating function does it.
note: The value from the base parameter will be divided per two in the resulting spiral.
Warning
The turns parameter value will be multiply per 2 to obtains the number of revolutions of the spiral.
The base parameter will be divided per two in the resulting spiral.
I can only generate even spirals.
## Wheels¶
Polygon *generate_wheel(uint32_t polygon, float radius, Pixel center, float offset, float orientation)
Parameters:
• polygon (uint32_t) – Number of sides of the wheel (base polygon).
• center (Pixel) – The center from the wheel.
• offset (float) – Size of the peaks of the wheel.
Return type:
Polygon *
Returns:
A pointed wheel according to the given settings.
note: The peaks of the wheel are trigons like a star. A blue 24 peaks wheel.
Note:
Note
You must set an offset value other than 0 because it represent the size of the peaks of the wheel.
The difference betwenn this wheel and a normal star is that is regular.
note: the radius Polygon member from this wheel is the radius of the base polygon from this wheel (interior).
Warning
The parameter polygon have a value conform to:
360 % polygon == 0
Polygon *generate_circular_saw_wheel(uint32_t polygon, float radius, Pixel center, float offset, float orientation, bool reverse)
Parameters:
• polygon (uint32_t) – Number of sides of the circular saw (base polygon).
• radius (float) – The radius from the points of the circular saw like wheel.
• center (Pixel) – The center from the circular saw like wheel.
• offset (float) – Size of the points.
• reverse (bool) – Reverse the shift from the circular saw like wheel.
Return type:
Polygon *
Returns:
A circular saw like pointed wheel.
note: This function generate an circular saw like wheel. This is only an polygon with an rectangle triangle on the top of the edges. A blue 24 peaks circular saw.
Note:
The radius goes from the center to the end of the pikes (it’s equal to the real_length value).
Warning
The parameter polygon have a value conform to:
360 % polygon == 0
Polygon *generate_wheel_peaks_trigon(uint32_t sides, float radius, Pixel center, float peak_offset, float orientation)
Parameters:
• sides (uint32_t) – Number of sides of the base polygon.
• radius (float) – An base value for generating the wheel (rounded polygon).
• center (Pixel) – Center from the wheel (rounded polygon).
• peak_offset (float) – Peak offset.
• orientation (float) – An offset in degrees to add to influence the incline of the wheel (rounded polygon).
Return type:
Polygon *
Returns:
A pointed wheel (rounded polygon) with peaks implemented as trigon which ends are mini arcs.
note: This function generate an wheel (rounded polygon) with peaking as trigons. A blue 24 trigon peaks wheel.
Note:
Warning
The parameter polygon have a value conform to:
360 % polygon == 0
Polygon *generate_wheel_peaks_rounded_square(uint32_t sides, float radius, Pixel center, float peak_length, float orientation)
Parameters:
• sides (uint32_t) – Number of sides from the wheel (rounded polygon).
• center (Pixel) – Center from the wheel (rounded polygon).
• peak_length (float) – Size of the peaks.
• orientation (float) – An offset in degrees to add to influence the incline of the wheel (rounded polygon).
Return type:
Polygon *
Returns:
A pointed wheel with peaks looking like a tube.
note: This function generate an pointed wheel (rounded polygon) with peaks looking like a tube but they are only right-angled line to the sides and connected trough an arc. A blue 24 rounded square peaks wheel.
Note:
Warning
The parameter sides have a value conform to:
360 % sides == 0 and sides <= 24 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.33052390813827515, "perplexity": 2805.863483027318}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-26/segments/1498128323895.99/warc/CC-MAIN-20170629084615-20170629104615-00424.warc.gz"} |
https://questioncove.com/updates/4d4f7cc9a805b76409dfc90b | Mathematics
OpenStudy (anonymous):
why does the square root of 2 over 2 + the square root of 2 over 2 =the square root of 2?
OpenStudy (anonymous):
a/2 + a/2 = a a = square root of 2
OpenStudy (anonymous):
$\sqrt{2}/2 + \sqrt{2}/2 = \sqrt{2} (1/2+1/2)= \sqrt{2} (1) = \sqrt{2}$
OpenStudy (anonymous):
Think of getting the sqrt of 2 out, as a common factor. Then add whats inside the bracket and then what do you get? :)
OpenStudy (anonymous):
$\sqrt{2}/2 = \sqrt{2} * 1/2$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7276254296302795, "perplexity": 1297.8117743005992}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323587767.18/warc/CC-MAIN-20211025185311-20211025215311-00710.warc.gz"} |
https://electronics.stackexchange.com/questions/480311/basic-diode-question-about-voltage-drop | # Basic diode question about voltage-drop
We have been begun studying diodes in electronics 1 and I have really basic question that may be really dumb but I cannot find an answer online.
If a diode is in series with a resistor and a voltage source that is set at the exact forward voltage drop value of the diode, what will be the voltage drop across the resistor? It can’t be zero but I’m guessing it must be close.
We have learned that normally you would subtract the forward voltage (0.7 V) from the loop but this circumstance doesn’t make sense to me.
• There is a Shockley diode equation. With it these solutions work out fine. Are you interested in it?
– jonk
Feb 9, 2020 at 6:33
• What is the current?? Feb 9, 2020 at 13:32
• Simple answer: There is no "exact forward drop voltage" i.e. the diode does not suddenly turn on and start conducting at that exact voltage, but has a more gradual slope, around that voltage. Feb 10, 2020 at 18:56
• It depends on the model you are expected to be using. Given electronics 1, you are probably expected to be using the Ideal Diode Model. Is this true? If not, what diode model have you been taught? Usually you will be expected to answer using whatever level of model has been taught in class. As your classes become more advanced, so do the models - and the answers (such as jonk's elaborate explanation). Or are you looking for a real-world answer to go along with the ideal models you've been taught?
– J...
Feb 11, 2020 at 20:07
## Sample Schematic
simulate this circuit – Schematic created using CircuitLab
(Most of the material that follows here can be readily found at this Wikipedia site: diode modeling. I will, however, take a different approach to their closed solution answer.)
## Shockley Diode Equation
Assuming operation at its calibration temperature, the only relevant equation for the LED is the Shockley diode equation:
$$I_\text{D}=I_\text{SAT}\left(e^{\frac{V_\text{D}}{\eta\, V_T}}-1\right)$$
That equation is readily re-worked to solve for $$\V_\text{D}\$$:
$$V_\text{D}=\eta\, V_T\,\operatorname{ln}\left(\frac{I_\text{D}}{I_\text{SAT}}+1\right)$$
So, we have two different perspectives on the diode/LED.
For a diode-connected small-signal BJT, it is usually the case that the emission co-efficient (aka non-ideality factor) is $$\\eta=1\$$. But for many discrete diodes such as the 1N4148 or 1N4007, $$\\eta>1\$$. (It won't be less than 1.) Some LEDs will have rather high values (exceeding 4. not infrequently.)
The saturation current, $$\I_\text{SAT}\$$, is best seen as an extrapolated $$\y\$$-axis intercept. I talk about it here and also here and here.
$$\V_T=\frac{k\, T}{q}\$$ is the statistical thermal voltage and is a basic physics parameter with many important uses. At room temperature, it's often taken to be $$\\approx 26\:\text{mV}\$$.
## Mathematical Closed Solution
The KVL equation for the above circuit is:
\begin{align*} V_\text{CC} - R\,I_\text{D} - V_\text{D} &= 0\:\text{V}\\\\ V_\text{CC} - R\,I_\text{D} - \eta\;V_T \, \ln{\left(\frac{I_\text{D}}{I_\text{SAT}}\right)} &= 0\:\text{V} \end{align*}
The problem here is in solving for $$\I_\text{D}\$$. You can easily solve this in an iterative fashion. Or, if you have a piece of paper with the diode equation plotted, you can use a ruler to add the resistor "load line" and find an approximate intercept. But for a closed mathematical solution without iteration, you need the product-log function (aka the LambertW function):
\begin{align*} V_\text{CC} - R\,I_\text{D} - \eta\;V_T \, \ln{\left(\frac{I_\text{D}}{I_\text{SAT}}\right)} &= 0\:\text{V}\\\\ \frac{V_\text{CC}}{\eta\,V_T} - \frac{R\,I_\text{D}}{\eta\,V_T} &= \ln{\left(\frac{I_\text{D}}{I_\text{SAT}}\right)}\\\\ e^{^{\frac{V_\text{CC}}{\eta\,V_T}-\frac{R\,I_\text{D}}{\eta\;V_T}}} &= \frac{I_\text{D}}{I_\text{SAT}}\\\\ 1 &= \frac{I_\text{D}}{I_\text{SAT}}\cdot e^{^{\frac{R\,I_\text{D}}{\eta\,V_T}-\frac{V_\text{CC}}{\eta\,V_T}}}\\\\ e^{^{\frac{V_\text{CC}}{\eta\,V_T}}} &= \frac{I_\text{D}}{I_\text{SAT}}\cdot e^{^{\frac{R\,I_\text{D}}{\eta\,V_T}}}\\\\ \frac{R\,I_\text{SAT}}{\eta\,V_T}\cdot e^{^{\frac{V_\text{CC}}{\eta\,V_T}}} &= \frac{R\,I_\text{D}}{\eta\,V_T}\cdot e^{^{\frac{R\,I_\text{D}}{\eta\,V_T}}}\\\\ &\text{set }u=\frac{R\,I_\text{D}}{\eta\,V_T}\\\\&\therefore\\\\ u\,e^u&=\frac{R\,I_\text{SAT}}{\eta\,V_T}\cdot e^{^{\frac{V_\text{CC}}{\eta\,V_T}}}\\\\ u&=\operatorname{LambertW}\left(\frac{R\,I_\text{SAT}}{\eta\,V_T}\cdot e^{^{\frac{V_\text{CC}}{\eta\,V_T}}}\right)\\\\ \frac{R\,I_\text{D}}{\eta\,V_T}&=\operatorname{LambertW}\left(\frac{R\,I_\text{SAT}}{\eta\,V_T}\cdot e^{^{\frac{V_\text{CC}}{\eta\,V_T}}}\right)\\\\ I_\text{D}&=\frac{\eta\,V_T}{R}\cdot\operatorname{LambertW}\left(\frac{R\,I_\text{SAT}}{\eta\,V_T}\cdot e^{^{\frac{V_\text{CC}}{\eta\,V_T}}}\right) \end{align*}
(For those interested in more details about the product-log function, aka LambertW, please see Wolfram's LambertW site.)
Now, suppose $$\V_\text{CC}=9\:\text{V}\$$ and $$\R=220\:\Omega\$$. For the LED, let's use parameters taken from a Luminus PT-121-B LED: $$\\eta=8.37\$$, and $$\I_\text{SAT}=435.2\:\text{nA}\$$. (Assume $$\V_T\approx 26\:\text{mV}\$$, of course.) Then we'd find $$\I_\text{D}\approx 29.9\:\text{mA}\$$ and $$\V_\text{D}\approx 2.42\:\text{V}\$$. This is very close to the Spice simulation for the device and circumstances.
Or suppose we use the parameters for the 1N4148, $$\\eta=1.752\$$, and $$\I_\text{SAT}=2.53\:\text{nA}\$$, and use $$\V_\text{CC}=5\:\text{V}\$$ and $$\R=1\:\text{k}\Omega\$$. Then, for this common diode, we'd find $$\I_\text{D}\approx 4.34\:\text{mA}\$$ and $$\V_\text{D}\approx 654\:\text{mV}\$$.
As you can see, this works for all diode types. (The main limitation is the fact that $$\I_\text{SAT}\$$ varies widely over temperature -- discussed towards the end of the discussion on 'simplified diode models' where its variations due to one of the most important results from statistical mechanics, the Boltzmann factor, are further discussed.)
## Summary
Closed solutions for basic diode questions are never basic. However, for most purposes it's usually enough to make a few simplifying assumptions and be "close enough for all intents and purposes." (To read about some of these, see 'simplified diode models' already mentioned a moment ago.) So you probably will never really need to do the above work. It's just nice to know what's involved, should you wonder about it. (Mostly, so you'll realize just why you use those simplifying assumptions, instead.)
Also take note that the closed solution is a large-scale solution and solves the question over a very, very large range of circumstances.
You were wondering about what happens when the applied voltage is equal to the diode voltage. But, in reality, the diode voltage adjusts itself to the circumstances. It's not fixed. So if you try to apply the so-called "diode voltage" to the circuit, the diode will instead adjust its voltage still lower so that the resistor's voltage drop will be "just enough" to provide the current that is "just enough" to yield the needed diode voltage to make up the difference. That's the real answer here. The above mathematical solution is just a complicated way of saying the same thing, but quantitatively instead of in a "hand-waving" way.
All of the above applies exactly the same as for any forward-biased diode of any kind. Even those with substantial (in the application) Ohmic lead resistance (which is then just added to the series resistance for analysis.)
• I appreciate this wording: "the diode will instead adjust its voltage ... just enough". Feb 10, 2020 at 6:11
• @pericynthion All the same parameters and logic still apply. The LED is just a segue. Not an error.
– jonk
Feb 10, 2020 at 8:59
• @pericynthion In fact, I mentioned regular dude types earlier in the text. Nothing changes in the analysis, at all.
– jonk
Feb 10, 2020 at 9:05
• This is my favorite answer on the whole electronics stack-exchange site by far. Short, to the point, and so deep that everyone who reads it learns something. Feb 10, 2020 at 9:15
• @user55924 Thanks for the kind words and I'm glad you can see the depth and breath. However, this is merely my parroting of the incredible work of a few very smart people long before me. Some appreciate it, some never will (to their own loss.)
– jonk
Feb 10, 2020 at 9:31
If you have a graph of current versus voltage for a diode you can draw "load lines" on them to solve your question. Here's one I had created for LEDs running from a 5 V supply. The voltages are higher than for a regular diode but the principle is the same.
Figure 1. The simple circuit.
Figure 2. Current versus forward voltage for a range of LEDs of different colours with load lines for various resistor values. Source: Loadline resistance graphic tool.
If we take the 100 Ω case of Figure 2 and the UV LED (because it is closest to the 5 V supply voltage) we can make the following observations:
• If Vf is 0 V then there is 5 V across R1 and the current would be 5/100 = 50 mA. The 100 Ω load line starts at (0, 50).
• If Vf is 5 V then there is 0 V across R1 and the current would be 0 mA. The 100 Ω load line ends at (5, 0).
• To see what current flows through the UV LED on a 5 V supply with 100 Ω for R1 just find the intersection of the load line with the UV curve. This is at 3.5 V and 15 mA.
• Given either the resistor value or the desired current you can quickly estimate the other from the graph.
If a diode is in series with a resistor and a voltage source that is set at the exact forward voltage drop value of the diode, what will be the voltage drop across the resistor?
Hopefully it's clear now that a diode doesn't have an "exact" forward voltage drop.
It can’t be zero but I’m guessing it must be close. We have learned that normally you would subtract the forward voltage (0.7 V) from the loop but this circumstance doesn’t make sense to me.
Your hunch is correct. You just need to remember that the current versus Vf graph is a curve, not a right angle.
Diode is a nonlinear element. For your question, assuming an ideal diode:
1. Diode when forward biased start conducting completely at 0.7 V.
2. The voltage source is also precisely set to 0.7 V.
3. The voltage drop across the R appears when there is a flow of current. The current can't flow since there is no voltage difference across the resistor. Drop is zero across the resistor.
Assume ideal Voltage source as well as a zero resistance for the resistor.
• The current will be zero if voltage is less than or equal to 0.7 V.
• The current will be infinite if voltage is greater than 0.7 V.
The problem here is that OP thinks the voltage drop across the diode is VF (about 0.7 V); so, including a voltage source with the same voltage VF, the result should be zero. However, this is valid if sufficient current flows through the diode (e.g., it is a basic requirement for a Zener voltage stabilizer)... and this requires higher supply voltage, which in this case is nowhere to be taken. As a result, as professionals say, "the diode is not properly biased". I have graphically illustrated this situation in Fig.1. Let's examine it.
Fig. 1. To work properly in the vertical part of its IV curve, the diode should be properly biased
To work properly (in the almost vertical part of its IV curve), the diode requires more significant current (IB) that can be obtained by higher voltage V and the resistance R. As a result, the load line (in brown) intersects the diode IV curve in the middle of the vertical part - the so-called "operating point" B, and the voltage drop across diode is VF = 0.7 V.
However, the OP's input voltage is only VF. So the load line has significantly moved to the left... and now it intersects the diode IV curve in the (almost) horizontal part of the IV curve - point A (the operating point has moved from the B to A position). Now the current IA is insufficient... and the voltage drop across diode is less than VF.
So, formulated in this way, the question has no practical value. It is just an undesired situation in the analog diode applications. But if somehow the diode is properly biased, the OPs question makes sense and can illustrate many interesting and important applications.
"Biasing" simply means "adding" constant voltage to the existing input voltage (V+ in the figure). If there was not a ground, there would be only one way to do it. But as we usually ground the diode (as in the figure), we can do it in two possible ways - from the side of anode ("pulling" it up) and from the side of cathode ("pulling" it down). Let's consider the latter as more interesting and more easily implemented - Fig. 2.
Fig. 2. Biasing a diode from the side of cathode
To bias the diode, we have connected another (but negative) voltage source V-. As we can see from the voltage picture (red bars), we can adjust V+ to make it equal to VF of operating point C (in the middle of the vertical part). As a result, the "output" voltage (of the cathode) is zero (the so-called "virtual ground"). As though the voltage V+ has neutralized the voltage drop VF across the diode... and the total voltage of this network consisting of V+ and D is zero. Figuratively speaking, we can think of the network as of "ideal diode" with zero voltage drop VF. Moreover, with more imagination, we can consider the voltage source V+ as a kind of "negative diode" -D that removes the "positive diode" D. It is negative since it adds voltage while the ordinary diode is positive since it subtracts voltage.
The name of this technique (can be) "voltage compensation"... where we compensate an undesired voltage drop by equivalent voltage in a series manner. It can be passive if VF is compensated by another VF across an equal diode. This technique is widely used to bias output (op)amp complementary stages with diode and "active diode" networks connected between transistor bases. Another application can be found in H&H AE (page 52, Fig. 1.93) where a diode log converter is compensated this way.
However, quite more interesting is the active voltage compensation. We can see it in the circuit of an op-amp log converter if we draw it in a more unusual way - Fig. 3. The elements with positive voltages are drawn above the zero voltage line (ground); the elements with negative voltages are drawn below the zero voltage line.
Fig. 3. In the op-amp log converter, the op-amp compensates VF by adding equal voltage -VF
The op-amp acts as the variable voltage source V+ from Fig. 2 above. It "goes" below zero to add voltage VF in series to the diode. As a result, the "output" voltage of the anode is zero (virtual ground)... the op-amp has neutralized the voltage drop VF across the diode... Figuratively speaking, we can think of the combination of (properly supplied) op-amp, power supply V- and imperfect diode as of an "ideal diode" with zero voltage drop VF... or, as above, we can think of the op-amp as a kind of "negative diode"-D that removes the "positive diode" D...
The voltage drop on a (real) diode is not fixed, but varies with current, temperature, and perhaps other conditions.
While in your circuit you slowly raise the source voltage, the voltage drop on the diode will also raise: it will be never greater than the source (otherwise you have a generator, not a diode). So a current flows, the resistor drops some voltage, and the system finds (automatically) an equilibrium because with less current and voltage, the diode lowers its voltage drop.
I think there is a much simpler "Electronics 1" answer to your question.
The voltage across the diode and the voltage across the resistor must sum to that of the voltage source. Thus if the voltage drop across the diode is its forward voltage drop (which would be the case in a simple ideal diode model - and that's the simplification I'm suggesting you are meant to make), then the voltage drop across the resistor is zero. A corollary is that no current flows.
Several other answers will tell you why this simplification is not always accurate, but given you've supplied no other data about the diode (presumably because you've been given one), I'd suggest you are meant to be making the above simplification.
There is a voltage vs current chart for the diode. Presuming a specific voltage and current level on the chart it can be determined that an infinitesimal change in voltage and current represents an equivalent resistance, therefore in series with the current limiting resistor. You can also guesstimate the led voltage, presume voltage current and power across the resistor based on Vcc minus this voltage, look up the voltage on the chart at this current and adjust current estimations based on this revised Vcc minus this adjusted junction voltage value accordingly. Keep in mind because of the increase in junction voltage due to temperature you are going to be approximate. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 26, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8931146860122681, "perplexity": 986.6112871107953}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662570051.62/warc/CC-MAIN-20220524075341-20220524105341-00182.warc.gz"} |
http://math.stackexchange.com/users/46247/audifanatic?tab=activity&sort=all&page=3 | # audiFanatic
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Mar30 comment Prove for a simple graph that $n-1 \leq m \leq \frac{n(n-1)}{2}$ exactly, that's what I'm not sure about. I can show that the other extreme is true as well by removing any $3$ edges. Removing any more than that makes the graph disconnected and the inequality would fail. However, I'm not exactly sure that showing this for the extreme cases would be considered a "proof" Mar30 comment Prove for a simple graph that $n-1 \leq m \leq \frac{n(n-1)}{2}$ 0oo, I didn't know I could use MathJax in titles too. thanks for the fix and teaching me something new Mar30 asked Prove for a simple graph that $n-1 \leq m \leq \frac{n(n-1)}{2}$ Mar30 comment Expectation of a Poisson Process I did, I'm not quite understanding. as far as I can tell from wikipedia, the inner function would be a function of $x$ en.wikipedia.org/wiki/Law_of_total_expectation Mar30 comment Expectation of a Poisson Process @Did Maybe it's a notation thing, this subject has a lot of different notations, but the inner expectation should be a function of $x$ and the outer one should turn it into a number, correct? Mar27 revised Expectation of a parallel system added 3 characters in body Mar27 comment Expectation of a parallel system What is $H_n$, the heavyside step function? Mar27 revised Expectation of a parallel system added 61 characters in body Mar27 asked Expectation of a parallel system Mar27 comment Conditioning on a random variable of course that only works if $\Lambda$ and $X$ are independent Mar27 comment Conditioning on a random variable No, thank you! Between both answers I think I've got this well understood now. I hate to have to pick just one of them as best because they were kinda complementary in helping me out Mar27 comment Conditioning on a random variable Multiplying leftmost and rightmost sides by $Pr(\Lambda = \lambda)$ (and dropping the middle term from the equation), we have $$Pr(X \geq 3 |\Lambda = \lambda)Pr(\Lambda = \lambda) = Pr(X \geq 3)$$ Rearranging, I have what you have: $$Pr(X \geq 3) = Pr(X \geq 3 |\Lambda = \lambda)Pr(\Lambda = \lambda)$$ And now we do this for all $\lambda$ Mar27 comment Conditioning on a random variable Not a problem at all; repetition is always good as long as it clears things up. So I think I see it now. So essentially we're fixing $\Lambda$ and asking ourselves what the desired probability would be for every value of $\lambda$. But we also need to be aware of the probability that $\Lambda$ takes on a certain value. In terms of conditional probability: $$Pr(X \geq 3 |\Lambda = \lambda) = \frac{Pr(X \geq 3, \Lambda = \lambda)}{Pr(\Lambda = \lambda)} = \frac{Pr(X \geq 3) Pr(\Lambda = \lambda)}{Pr(\Lambda = \lambda)}$$ multiplying both sides by $Pr(\Lambda = \lambda$) we have...next post Mar27 comment Conditioning on a random variable But regarding the $ds$ stuff, so what you're saying is that the probability that $\Lambda$ is on the set (0,5) is $$\frac{(s+ds)-s}{5}$$ and the $s$ cancels out so we're left with $$\frac{ds}{5}$$ But after that I'm lost because you made the variable we're integrating over $x$ and I don't see any $x$'s in the integration. Typo perhaps? Mar27 comment Conditioning on a random variable Sorry, deleated comment to fix $LaTeX{}$ issues, so they're out of order now, but anyway. So what you're saying is that we multiply the density and mass functions together because by the definition of conditional probability: $$Pr(X = k | \Lambda = \lambda) = \frac{Pr(X = k , \Lambda = \lambda)}{Pr(\Lambda = \lambda)}$$ Mar27 asked Conditioning on a random variable Mar24 comment Expectation of a Poisson Process Ah, now it's clear. Exactly what I wanted; once you said it wasn't really recursion, then it ecame obvious to just factor out an $E[W]$ and solve. Mar24 revised Expectation of a Poisson Process added 213 characters in body Mar24 comment Expectation of a Poisson Process Yes, like I say above, I'm confused about what to do with this recursive integral. I'm gonna go to bed; need to be up in 3 hours. But I will look at this again tomorrow (or technically later today) Mar24 comment Probability question with interarrival times Ok, thanks. Could you take a look at my question? It is somewhat similar to this one, but the approach I took is different. math.stackexchange.com/questions/724228/… | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8524574041366577, "perplexity": 386.14085461072995}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-23/segments/1405997894473.81/warc/CC-MAIN-20140722025814-00115-ip-10-33-131-23.ec2.internal.warc.gz"} |
https://forum.theotown.com/viewtopic.php?p=59779 | ## Functionality using fun
Any information about the fun attribute is given here.
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### Functionality using fun
Hi,
in this topic I'll try to give a step-by-step guide into fun functionality. Dependent on your current knowledge it might need some time getting used to it. However, fun is a real powerful tool to create buildings that react to their environment or to user interaction. By now (version 343) the system is for from completion. Nevertheless, functionality as it's described here should still work with future updates as new functionality will be added primarily.
1. Getting started
To keep it simple I'll just focus on the fun part of a sample plugin. For this reason I'll use frames which are built right into the game so you don't have to bother with them. However, you can make them as complex as usual for your projects. Also building size isn't limited by fun, but a size of width:1, height:1 makes it much easier.
Let this be our starting point of a simple plugin:
Code: Select all
[
{
"id":"$deco_fun_sample00", "type":"decoration", "width":1, "height":1, "frames":[{"x":288,"y":0,"w":32,"h":32,"count":2,"offset x":1024,"offset y":1024}] } ] You don't have to worry about the frames definition, it just means that we load two frames of this image: fun_frames.png (1.08 KiB) Viewed 5279 times So, now let's add some fun to it. To do so, we use the fun attribute: Code: Select all [ { ... // Just as before "fun":[ { "condition":{"type":"building","frame":0}, "actions":[ {"type":"frame","frame":1} ] } ] } ] Try to guess what this code does. Solution: If the building was placed with frame 0, it will eventually switch to frame 1. Let's analyze "fun" a bit further. It takes an array of objects which we refer to as transitions (as they are similar to the transitions in a state machine). A transition has the form (simplified) Code: Select all if (condition) then do actions The ability to provide multiple transitions allows us to perform different actions on different conditions. Details about when and which transition will be taken will follow later. What does the condition Code: Select all {type":"building","frame":0} exactly to? It checks whether there's a building at the current position (that is the position of the building in which we define fun) which also has set frame 0 as current frame. If this is true, the condition evaluates to true so the actions can be performed. We provide a single action Code: Select all {"type":"frame","frame":1} which tries to set the frame of the building at the current position (so of this building) to 1. 2. Multiple transitions For now, it's boring if our plugin just switched frame 0 to 1. We want to switch back from 1 to 0 eventually. To do so, we can use the ability to provide multiple transitions: Code: Select all [ { ... // As before "fun":[ { "condition":{"type":"building","frame":0}, "actions":[ {"type":"frame","frame":1} ] }, { "condition":{"type":"building","frame":1}, "actions":[ {"type":"frame","frame":0} ] } ] } ] Simple, isn't it? But wait, you might say what if the frame is 0 the first transition's condition will be true so the first action will be performed. But after that, the condition of the second transition becomes true so that the frame will be set back to 0 immediately. True, but that's not how transitions and their actions are executed. Instead, all conditions of all transitions are evaluated at the same time. After that, only one transition whose condition was true is selected to perform it's actions. If no condition was true, no actions will be performed. How often does this happen? For "fun" this process is performed daily. So the building will switch it's frame each day except you pause the game. 3. Tap sensitivity You might say that we can achieve the exact same behavior by using an animation. That's true, and for this functionality I would also recommend to use animations instead as it's much easier. But what if we want our building to change it's frame only if the user taps on it? We cannot achieve this with animations alone, but with fun it's fairly easy: We just have to replace "fun" with "on click fun". This fun will be performed only if the user taps on the building. So our final code for this looks like that: Code: Select all [ { "id":"$deco_fun_sample00",
"type":"decoration",
"width":1,
"height":1,
"frames":[{"x":288,"y":0,"w":32,"h":32,"count":2,"offset x":1024,"offset y":1024}],
"on click fun":[
{
"condition":{"type":"building","frame":0},
"actions":[
{"type":"frame","frame":1}
]
},
{
"condition":{"type":"building","frame":1},
"actions":[
{"type":"frame","frame":0}
]
}
]
}
]
Note that you can define "fun" and "on click fun" both in a single plugin. So you can do both, daily transitions as well as touch sensitive transitions. This is used for example in these sample plugins:
Wandering Animals
Game of Life
...
Brody Craft
Inhabitant of a Infinity
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### Re: Fun
This is very mind bending
When you get to be called a Board Index because you are too good.>:3
Lobby
Developer
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### Re: Fun
Any questions? I know that it's not easy.
...
Brody Craft
Inhabitant of a Infinity
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### Re: Fun
No questions...
When you get to be called a Board Index because you are too good.>:3
Ølsken
Former Bearbear65
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Plugins: Show
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### Re: Fun
Brody Craft wrote:
Wed Sep 13, 2017 12:43
No questions...
Trust me this is hard
But it feels so good when you finally get it right
Just my opinion
Josh
Graphic designer
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### Re: Functionality using fun
You can make whole new systems with this
Proud TheoTown player sinds update 1.1.50
Creator of Aldorria, Covinton Empire, West Country, Sunnydale
Save nature, before it kills you
KINGTUT10101
1,000,000 inhabitants
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### Re: Functionality using fun
Could you help me figure out how to make a plug-in that will replace nearby buildings. Basically a building that will spread if it's next to other buildings.
CommanderABab
AB
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### Re: Functionality using fun
Build is in the actions.
ps890giv psdl8bzi<
Lobby
Developer
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### Re: Functionality using fun
The syntax isn't correct, in JSON objects consist of name:value-pairs while your "$building2" stands alone (how sad). To check for a building, use type:building and provide your id as value of id:value. See here: Code: Select all "condition":{"type":"and","x":1,"inner":[ {"type":"building","id":"$building2"}
]},
If you have only one condition you can simplify the code by removing the and-group:
Code: Select all
"condition":{"type":"building","id":"$building2"}, ... Lobby Developer Reactions: Posts: 3406 Joined: Sun Oct 26, 2008 12:34 Plugins: Show Version: Beta Phone model: S7 edge #### Platform ### Re: Functionality using fun 4 tiles into each direction? Do you mean like the red tiles here?: ... Lobby Developer Reactions: Posts: 3406 Joined: Sun Oct 26, 2008 12:34 Plugins: Show Version: Beta Phone model: S7 edge #### Platform ### Re: Functionality using fun I would use "count" to do that. count evaluates all inner conditions and counts how many of them hold true. Let's say it found n true conditions. The count condition is then true iff min≤n≤max or n=z (depending on whether you provided min, max or z). Code: Select all "condition":{"type":"count","z":0,"inner":[ {"type":"building","id":"$building2","x":1},
{"type":"building","id":"$building2","x":2}, {"type":"building","id":"$building2","x":3},
{"type":"building","id":"$building2","x":4}, {"type":"building","id":"$building2","y":1},
{"type":"building","id":"$building2","y":2}, {"type":"building","id":"$building2","y":3},
{"type":"building","id":"$building2","y":4}, {"type":"building","id":"$building2","x":-1},
{"type":"building","id":"$building2","x":-2}, {"type":"building","id":"$building2","x":-3},
{"type":"building","id":"$building2","x":-4}, {"type":"building","id":"$building2","y":-1},
{"type":"building","id":"$building2","y":-2}, {"type":"building","id":"$building2","y":-3},
{"type":"building","id":"$building2","y":-4} ]}, This code isn't short by any means, but at least it works ... Ølsken Former Bearbear65 Reactions: Posts: 4977 Joined: Fri Feb 10, 2017 14:53 Plugins: Show Version: Beta Phone model: Samsung S10 #### Platform #### Plugin Creator ### Re: Functionality using fun Is it possible to make a plug-in with functions like this Also if it is tell me I need help For example you have four buildings A¹ , A² , B¹ , B² If you click A¹ you will get A² but you can only turn A² back into A¹ if B² is next to it also to prevent B² making A² into A¹ accidentally There is 2 modes for the B building B¹ (off) B² (on) If you click B¹ (off) you get B² (on) that can change A² back to A¹ so simply B building is like a switch and A building is like a light bulb Just my opinion CommanderABab AB Reactions: Posts: 8143 Joined: Tue Jun 07, 2016 21:12 Plugins: Show Version: Beta #### Platform #### Plugin Creator ### Re: Functionality using fun Yes ps890giv psdl8bzi< Ølsken Former Bearbear65 Reactions: Posts: 4977 Joined: Fri Feb 10, 2017 14:53 Plugins: Show Version: Beta Phone model: Samsung S10 #### Platform #### Plugin Creator ### Re: Functionality using fun How? Just my opinion CommanderABab AB Reactions: Posts: 8143 Joined: Tue Jun 07, 2016 21:12 Plugins: Show Version: Beta #### Platform #### Plugin Creator ### Re: Functionality using fun temp.json (1.56 KiB) Downloaded 25 times Code: Select all //Is it possible to make a plug-in with functions like this // Also if it is tell me I need help //For example you have four buildings // A¹ , A² , B¹ , B² //If you click A¹ you will get A² //but you can only turn A² back into A¹ //if B² is next to it also to prevent B² // making A² into A¹ accidentally //There is 2 modes for the B building // B¹ (off) B² (on) //If you click B¹ (off) you get B² (on) //that can change A² back to A¹ //so simply B building is like a switch and A //building is like a light bulb {"id":"a1", "build time":0, "on click fun":[ { "condition":{ {"type":"building","id":"a1"}, }, "actions":[ {"type":"remove"}, {"type":"build","id":"a2"} ], "p":1 } ] }, {"id":"a2", "build time":0, "on click fun":[ { "condition":{ {"type":"building nearby","id":"b2","min":1,"max":8}, }, "actions":[ {"type":"remove"}, {"type":"build","id":"a1"} ], "p":1 } ] }, {"id":"b1", "build time":0, "on click fun":[ { "condition":{ {"type":"building","id":"b1"}, }, "actions":[ {"type":"remove"}, {"type":"build","id":"b2"} ], "p":1 } ] }, {"id":"b2", "build time":0, "on click fun":[ { "condition":{ {"type":"building","id":"b2"}, }, "actions":[ {"type":"remove"}, {"type":"build","id":"b1"} ], "p":1 } ] }, ps890giv psdl8bzi< CommanderABab AB Reactions: Posts: 8143 Joined: Tue Jun 07, 2016 21:12 Plugins: Show Version: Beta #### Platform #### Plugin Creator ### Re: Functionality using fun Lobby : Code: Select all "random fun":[] can be used to create new stuff randomly Me: Lol Lobby : it's transitions are called for random x,y on the map Me: That could be disastrous. Cause pipe leaks and so forth. Lobby : Yes, might be used for something like that ps890giv psdl8bzi< CommanderABab AB Reactions: Posts: 8143 Joined: Tue Jun 07, 2016 21:12 Plugins: Show Version: Beta #### Platform #### Plugin Creator ### Re: Functionality using fun ps890giv psdl8bzi< KINGTUT10101 1,000,000 inhabitants Reactions: Posts: 1957 Joined: Thu Jul 07, 2016 22:50 Location: 'Merica Plugins: Show Version: Beta Phone model: Moto x4 #### Platform #### Plugin Creator ### Re: Functionality using fun Can we make a building detect what frame another building is on? @Lobby Lobby Developer Reactions: Posts: 3406 Joined: Sun Oct 26, 2008 12:34 Plugins: Show Version: Beta Phone model: S7 edge #### Platform ### Re: Functionality using fun Yes: Code: Select all "condition":{"type":"building","id":"$otherbuildingid","x":1,"y":0,"frame":7}
Use x and y to look relatively to the current building's position. "x":1,"y":0 is the neighboring tile in south-east direction (if the city is not rotated).
...
KINGTUT10101
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### Re: Functionality using fun
What code can be used for fun where the condition is always true?
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https://fenicsproject.org/olddocs/dolfin/latest/python/demos/stokes-iterative/demo_stokes-iterative.py.html | # Stokes equations with an iterative solver¶
This demo is implemented in a single Python file, demo_stokes-iterative.py, which contains both the variational forms and the solver.
This demo illustrates how to:
• Read mesh and subdomains from file
• Use mixed function spaces
## Equation and problem definition¶
### Strong formulation¶
$\begin{split}- \nabla \cdot (\nabla u + p I) &= f \quad {\rm in} \ \Omega, \\ \nabla \cdot u &= 0 \quad {\rm in} \ \Omega. \\\end{split}$
Note
The sign of the pressure has been flipped from the classical definition. This is done in order to have a symmetric (but not positive-definite) system of equations rather than a non-symmetric (but positive-definite) system of equations.
A typical set of boundary conditions on the boundary $$\partial \Omega = \Gamma_{D} \cup \Gamma_{N}$$ can be:
$\begin{split}u &= u_0 \quad {\rm on} \ \Gamma_{D}, \\ \nabla u \cdot n + p n &= g \, \quad\;\; {\rm on} \ \Gamma_{N}. \\\end{split}$
### Weak formulation¶
The Stokes equations can easily be formulated in a mixed variational form; that is, a form where the two variables, the velocity and the pressure, are approximated simultaneously. Using the abstract framework, we have the problem: find $$(u, p) \in W$$ such that
$a((u, p), (v, q)) = L((v, q))$
for all $$(v, q) \in W$$, where
$\begin{split}a((u, p), (v, q)) &= \int_{\Omega} \nabla u \cdot \nabla v - \nabla \cdot v \ p + \nabla \cdot u \ q \, {\rm d} x, \\ L((v, q)) &= \int_{\Omega} f \cdot v \, {\rm d} x + \int_{\partial \Omega_N} g \cdot v \, {\rm d} s. \\\end{split}$
The space $$W$$ should be a mixed (product) function space $$W = V \times Q$$, such that $$u \in V$$ and $$q \in Q$$.
### Domain and boundary conditions¶
In this demo, we shall consider the following definitions of the input functions, the domain, and the boundaries:
• $$\Omega = [0,1]\times[0,1] \backslash {\rm dolphin}$$ (a unit cube)
• $$\Gamma_D =$$
• $$\Gamma_N =$$
• $$u_0 = (- \sin(\pi x_1), 0.0)$$ for $$x_0 = 1$$ and $$u_0 = (0.0, 0.0)$$ otherwise
• $$f = (0.0, 0.0)$$
• $$g = (0.0, 0.0)$$
## Implementation¶
The Stokes equations as formulated above result in a system of linear equations that is not positive-definite. Standard iterative linear solvers typically fail to converge for such systems. Some care must therefore be taken in preconditioning the systems of equations. Moreover, not all of the linear algebra backends support this. We therefore start by checking that either “PETSc” or “Tpetra” (from Trilinos) is available. We also try to pick MINRES Krylov subspace method which is suitable for symmetric indefinite problems. If not available, costly QMR method is choosen.
from dolfin import *
# Test for PETSc or Tpetra
if not has_linear_algebra_backend("PETSc") and not has_linear_algebra_backend("Tpetra"):
info("DOLFIN has not been configured with Trilinos or PETSc. Exiting.")
exit()
if not has_krylov_solver_preconditioner("amg"):
info("Sorry, this demo is only available when DOLFIN is compiled with AMG "
"preconditioner, Hypre or ML.")
exit()
if has_krylov_solver_method("minres"):
krylov_method = "minres"
elif has_krylov_solver_method("tfqmr"):
krylov_method = "tfqmr"
else:
info("Default linear algebra backend was not compiled with MINRES or TFQMR "
"Krylov subspace method. Terminating.")
exit()
Next, we define the mesh (a UnitCubeMesh) and a mixed finite element TH. Then we build a FunctionSpace on this element. (This mixed finite element space is known as the Taylor–Hood elements and is a stable, standard element pair for the Stokes equations.)
# Load mesh
mesh = UnitCubeMesh.create(16, 16, 16, CellType.Type.hexahedron)
# Build function space
P2 = VectorElement("Lagrange", mesh.ufl_cell(), 2)
P1 = FiniteElement("Lagrange", mesh.ufl_cell(), 1)
TH = P2 * P1
W = FunctionSpace(mesh, TH)
Next, we define the boundary conditions.
# Boundaries
def right(x, on_boundary): return x[0] > (1.0 - DOLFIN_EPS)
def left(x, on_boundary): return x[0] < DOLFIN_EPS
def top_bottom(x, on_boundary):
return x[1] > 1.0 - DOLFIN_EPS or x[1] < DOLFIN_EPS
# No-slip boundary condition for velocity
noslip = Constant((0.0, 0.0, 0.0))
bc0 = DirichletBC(W.sub(0), noslip, top_bottom)
# Inflow boundary condition for velocity
inflow = Expression(("-sin(x[1]*pi)", "0.0", "0.0"), degree=2)
bc1 = DirichletBC(W.sub(0), inflow, right)
# Collect boundary conditions
bcs = [bc0, bc1]
The bilinear and linear forms corresponding to the weak mixed formulation of the Stokes equations are defined as follows:
# Define variational problem
(u, p) = TrialFunctions(W)
(v, q) = TestFunctions(W)
f = Constant((0.0, 0.0, 0.0))
L = inner(f, v)*dx
We can now use the same TrialFunctions and TestFunctions to define the preconditioner matrix. We first define the form corresponding to the expression for the preconditioner (given in the initial description above):
# Form for use in constructing preconditioner matrix
Next, we want to assemble the matrix corresponding to the bilinear form and the vector corresponding to the linear form of the Stokes equations. Moreover, we want to apply the specified boundary conditions to the linear system. However, assembling the matrix and vector and applying a DirichletBC separately will possibly result in a non-symmetric system of equations. Instead, we can use the assemble_system function to assemble both the matrix A, the vector bb, and apply the boundary conditions bcs in a symmetric fashion:
# Assemble system
A, bb = assemble_system(a, L, bcs)
We do the same for the preconditioner matrix P using the linear form L as a dummy form:
# Assemble preconditioner system
P, btmp = assemble_system(b, L, bcs)
Next, we specify the iterative solver we want to use, in this case a KrylovSolver. We associate the left-hand side matrix A and the preconditioner matrix P with the solver by calling solver.set_operators.
# Create Krylov solver and AMG preconditioner
solver = KrylovSolver(krylov_method, "amg")
# Associate operator (A) and preconditioner matrix (P)
solver.set_operators(A, P)
We are now almost ready to solve the linear system of equations. It remains to specify a Vector for storing the result. For easy manipulation later, we can define a Function and use the vector associated with this Function. The call to solver.solve then looks as follows
# Solve
U = Function(W)
solver.solve(U.vector(), bb)
Finally, we can play with the result in different ways:
# Get sub-functions
u, p = U.split()
# Save solution in VTK format
ufile_pvd = File("velocity.pvd")
ufile_pvd << u
pfile_pvd = File("pressure.pvd")
pfile_pvd << p | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9082847237586975, "perplexity": 2593.0739015001905}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964362230.18/warc/CC-MAIN-20211202145130-20211202175130-00269.warc.gz"} |
http://bayeconsoft.com/html_documentationse23.html | ### 3.8 Interface to GNU Octave
GNU Octave is free software designed as a matrix programming language, which is largely compatible with MATLAB. Later versions of GNU Octave feature a simple GUI, but the vast majority of functions can still be accessed only using code. GNU Octave is intended for numerical computations, in general, and graphics, but it can be also used for performing Bayesian inference, especially when using some of its statistics-oriented loadable modules.
BayESoctave() function provides a convenient interface to GNU Octave, which allows the user to:
• pass BayES matrices and datasets as input to GNU Octave
• request GNU Octave to execute code written in its native language
• retrieve output from GNU Octave and store it in BayES matrix items; all data to be returned from GNU Octave are stored inside a BayES structure item
The general syntax of the octave() function is the following:10
$\left[$<structure name> = $\right]$ octave( <GNU Octave .m file>
$\left[$, "data"=<list of matrices/datasets to pass to GNU Octave> $\right]$
$\left[$, "return"=<list of matrices to retrieve from GNU Octave> $\right]$
);
where:
• <structure name> is a BayES id value which will be associated with the BayES structure that the octave() function returns. This structure will contain any GNU Octave matrices that the user requests to be returned to BayES (using the "return" option) after execution of the GNU Octave .m file completes.
• <GNU Octave .m file> is a string pointing to the file which contains the code (written in GNU Octave’s language) that GNU Octave will be requested to execute. If this file is not in the current directory then the file name must be prepended by the path to the file, either in absolute terms (eg. "C:/MyFiles/myFile.m") or relative to the current working directory (eg. "../myFile.m"). This is the only mandatory argument of the octave() function.
• "data" specifies the data that will be passed as input to GNU Octave. These can be either BayES datasets or matrices. <list of matrices/datasets to pass to GNU Octave> is a list of the id values of matrices or datasets (comma-separated names inside curly brackets), as they appear in the GNU Octave .m file. These matrices or datasets must be defined in the current workspace. When either a BayES matrix or dataset is passed as input to GNU Octave then it becomes available as a GNU Octave matrix. That is, BayES datasets are stripped of their additional information (most importantly, variable names and dataset structure) and only the raw data are passed to GNU Octave.
• "return" specifies the GNU Octave matrices that will be returned to BayES when execution of the GNU Octave .m file completes. <list of matrices to retrieve from GNU Octave> is a list of id values (comma-separated id values inside curly brackets) that specify the names of the matrices that should be returned from GNU Octave, as they appear in the GNU Octave .m file. Any GNU Octave matrix that is returned will be stored in BayES as a matrix and all returned matrices are grouped together into a BayES structure. Passing other data types (structures, cells, strings, etc.) between BayES and GNU Octave is not supported.
As the octave() function executes, GNU Octave attempts to print output on the system’s command console. BayES grabs this output and redirects it to the BayES main console in real time. This output is entirely determined by GNU Octave and the commands contained in the GNU Octave .m file provided to octave().
The sample script file in "\$BayESHOME/Samples/5$-$Interfaces/octave" contains an example of using the octave() function, along with a simple GNU Octave .m file. The GNU Octave interface is also accessible from the BayES main menu via Interfaces GNU Octave.
10Arguments inside square brackets are optional. Optional arguments passed to the octave() function can be provided in any order, but always after the mandatory argument (GNU Octave .m file). Optional arguments always come in pairs (eg. "data"={myDataset,myMatrix}). | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 7, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5720180869102478, "perplexity": 3267.301017043889}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623487611320.18/warc/CC-MAIN-20210614013350-20210614043350-00628.warc.gz"} |
https://byjus.com/jee/diffusion-of-gases/ | # Diffusion of Gases
## What is Diffusion?
Before discussing the diffusion of gases, let’s know a bit about what is diffusion? The diffusion is a net movement of atoms or molecules from highly concentrated region to low concentration region. In other words, the movement of atoms or molecules from high chemical potential region to the low chemical potential region.
The word diffusion is derived from a Latin word – diffuser, to spread out. Which means a substance that spreads out or moving from an area to another. Diffusion should not be confused with other transport phenomena like advection or convection, where it uses move particles from one place to another in a bulk motion.
The movement of molecules in solids is very small, relatively large in liquids and very large in gases. And this movement of molecules has to lead to a phenomenon called as diffusion.
## Diffusion of Gases:
The thermal motion of gas particles at above absolute zero temperature is called molecular diffusion. The rate of this phenomenon movement is a function of the viscosity of the gas, temperature, and size of the particles. The result of diffusion is a slow mixing of materials where the distribution of molecules or atoms are uniform.
## Rate of Diffusion:
Rate of Diffusion = $\frac{Amount \;of \; Gas \; Passing \; Through \; an \; Area}{Unit \; of \; Time}$
Here is an example to understand the diffusion of gases. Take a container, separating it into two partitions. Keep two gases A and B at the same pressure in two parts of the container. The molecules of gas A and B are in continuous random motion in its respective compartments. Now, remove the partition of the container. The molecules of gas A will begin to stray into gas B due to the random motion. In the same way, the molecules of gas B will begin to stray into gas A due to the random motion. As time passes, the molecules of both gases continue to stay each other. In a period of time, the whole mass of gas in the container will be a homogeneous mixture of gas A and gas B and this results because of the phenomenon called as diffusion.
Test your Knowledge on diffusion of gases
#### 1 Comment
1. Prashansa Pal
this was useful | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 1, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7180742621421814, "perplexity": 436.77840964183486}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-31/segments/1627046150266.65/warc/CC-MAIN-20210724125655-20210724155655-00278.warc.gz"} |
https://human.libretexts.org/Bookshelves/Composition/Book%3A_Introduction_to_College_Composition_(Lumen)/02%3A_Writing_Process/13%3A_Drafting/13.1%3A_Outcome%3A_Drafting | # 13.1: Outcome: Drafting
Skills to Develop
• Analyze strategies for drafting from an outline
• Analyze considerations unique to early drafts
• Analyze the value of multiple drafts
## Analyze drafting activities
Writing is a way to end up thinking something you couldn’t have started out thinking. – Peter Elbow, Writing Without Teachers
According to Elbow, the best way to accomplish deep thinking is a series of drafts which come together to produce an emerging “center of gravity” that then translates into the main focus on the work. This process should be a holistic process, not a linear process. Elbow’s reasoning behind this concept of multiple drafts follows the idea that, “if [a writer] learns to maximize the interaction among his own ideas or points of view, he can produce new ones that didn’t seem available to him.”
In other words, it’s difficult to predict where your thoughts and your argument will end up when working on an essay draft. And that’s a good thing.
This is the reason that writing assignments are so common in higher education: they develop a deep level of thinking that’s only possible through this process.
Figure $$\PageIndex{1}$$
### The Learning Activities for This Outcome Include
• Video: Moving From Outline to Draft
• Text: The First Draft is the Ugliest
• Text: Revising and Writing a Second Draft
• Self Check: Drafting
• Try It: Drafting | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.23393896222114563, "perplexity": 2828.6422634817786}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-18/segments/1555578663470.91/warc/CC-MAIN-20190424214335-20190425000335-00330.warc.gz"} |
http://www.electropedia.org/iev/iev.nsf/17127c61f2426ed8c1257cb5003c9bec/0d74fb139e51623fc1257f9d0037f117?OpenDocument | IEVref: 103-08-15 ID: Language: en Status: Standard Term: median Synonym1: Synonym2: Synonym3: Symbol: Definition: 0,5-fractile of a probability distribution for n real values not necessarily different from each other, real number such that the number of values less than it is equal to the number of values greater than itNote 1 to entry: If n is odd, the median is the value of rank $\left(n+1\right)/2$ when the values are arranged in increasing order. If n is even, the median may be any number between the values of rank $n/2$ and $\left(n/2+1\right)$, usually the arithmetic mean of these two values. Publication date: 2009-12 Source: Replaces: Internal notes: 2017-02-20: Editorial revisions in accordance with the information provided in C00020 (IEV 103) - evaluation. JGO CO remarks: TC/SC remarks: VT remarks: Domain1: Domain2: Domain3: Domain4: Domain5: | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 6, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.820704996585846, "perplexity": 1983.93245925426}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-09/segments/1518891817908.64/warc/CC-MAIN-20180226005603-20180226025603-00478.warc.gz"} |
http://cs.stackexchange.com/questions/22573/whats-flawed-about-the-save-the-input-method-of-reversible-computing | # What's flawed about the “save-the-input” method of reversible computing?
I'm an undergraduate just beginning to read about reversible computing. I know that, because of Landauer's principle, irreversible computations dissipate heat (and reversible ones do not). I brought it up with my professor, who had never heard of reversible computing before, and he was having difficulty understanding why the theory of reversible computing was not trivial.
His point was just that you can always save the input, i.e. for any function $f: \{ 0, 1 \}^n \rightarrow \{ 0, 1 \}^n$ that you wish to make reversible, define a new function $f_{reversible}: \{ 0, 1 \}^n \rightarrow \{0, 1 \}^{2n}$ (or $\{ 0, 1 \}^{2n} \rightarrow \{0, 1 \}^{2n}$ and you just put $0$s in for the last $n$ bits of the input) which returns the output in the first $n$ bits and the input in the other $n$ bits. Then in order to invert $f_{reversible}$ you just discard the output and return the input that you saved.
My immediate objection was that this takes more memory than the original function did -- though only by a constant factor. Constraining the output to $n$ bits would seem to restore the interesting-ness of the problem, though. Is this what is usually meant by reversible computing?
Another objection seemed to be that when we discard the output, we're doing something irreversible which is going to dissipate heat. But we correctly recovered the initial state, so how could it be irreversible? I don't know enough physics to understand whether the important thing w/r/t heat is just for the entire computation to be reversible, or whether every step needs to be reversible as well, or if this idea is just up the wrong tree.
-
## migrated from cstheory.stackexchange.comMar 13 '14 at 5:41
This question came from our site for theoretical computer scientists and researchers in related fields.
There are two important features of reversible computing that are missing from your discussion of reversible computing:
1. A reversible function has to be a bijection, and
2. Reversibility is defined on the level of local gates, not just the global level.
In particular, for your extension of $\{0,1\}^n \rightarrow \{0,1\}^n$ into $\{0,1\}^{2n} \rightarrow \{0,1\}^{2n}$ by copying, you don't ensure bijection because you don't explain what happens when the last $n$ bits of input for your function aren't $0^n$.
As for the second point, that is really the essential part of reversible-computing from the physics perspective. The physical process can't simply "undo" heating at a global level, thus every gate has to be reversible for the circuit to be reversible in the relevant-to-physics sense.
Finally, the theory of reversible computing is not unreasonably complicated, but it is definitely not trivial. In particular, there are some circuits that can be implemented with strictly fewer registers/wires non-reversibly than they can be reversibly. However, the blow up in going from non-reversible to reversible is not too bad.
In general, I seldom hear reversible computing come up in classical CS courses, because it is seldom relevant to classical computation. However, it is an important topic in quantum computing because all quantum circuits are reversible and because one has to handle what is on your 'junk' wires carefully to avoid unnecessary entanglement.
-
Aha. So what's the formal statement of "every gate has to be reversible" -- is it requiring the transition function of the Turing machine to be injective? – Eli Rose Mar 13 '14 at 6:27
@EliRose reversible computing is defined in the gate model, not the TM model. I am not sure if there is a reasonable definition in the TM model, but it would probably at least require the finite control to be reversible. So reversible gates means something like the Toffoli gate. – Artem Kaznatcheev Mar 13 '14 at 6:40
@ArtemKaznatcheev: what about Reversible Turing Machines (PDF link) introduced by Bennett? – Niel de Beaudrap Mar 13 '14 at 7:36
Combinatorial circuits can easily be handled with reversible logic, but all useful computing devices require feedback. One could use a Toffoli gate to compute "A and not B", and two such gates could be used to build a latch, but once the feedback is put in place, reversibility goes out the window. – supercat Mar 13 '14 at 18:04
what about quantum TMs whose allowed amplitudes can only be 0 or 1. That seems a reasonable way to define a reversible TM. – Marcos Villagra Mar 14 '14 at 15:30 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8346241116523743, "perplexity": 639.4671346789492}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-11/segments/1424936462548.53/warc/CC-MAIN-20150226074102-00007-ip-10-28-5-156.ec2.internal.warc.gz"} |
https://www.math.tamu.edu/courses/math171/ | MATH 171 - Calculus I - Fall 2021
Credits 4. 4 Lecture Hours.
Vectors, functions, limits, derivatives, Mean Value Theorem, applications of derivatives, integrals, Fundamental Theorem of Calculus. Designed to be more demanding than MATH 151. Only one of the following will satisfy the requirements for a degree: MATH 131, MATH 142, MATH 147, MATH 151 and MATH 171.
Prerequisite: MATH 150 or equivalent or acceptable score on TAMU Math Placement Exam.
Course DescriptionWeekly Schedule MYMathApps CalculusDerivative Bee (Fall only)
Sections
Sec Instructor Lecture
501 Emil Straube MWF 10:20-11:10am BLOC 161
502 Wencai Liu TR 8:00-9:15am BLOC 163
503 Philip Yasskin MWF 11:30-12:20pm BLOC 161
504 Irina Bobkova TR 11:10-12:25pm BLOC 149 | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.834052324295044, "perplexity": 15497.688487815876}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323585381.88/warc/CC-MAIN-20211021040342-20211021070342-00134.warc.gz"} |
http://www.linyekexue.net/CN/10.11707/j.1001-7488.20180610 | • 论文与研究报告 •
### 不同脂肪源人工饲料对蠋蝽生长发育及生殖力的影响
1. 1. 北京林业大学省部共建森林培育与保护教育部重点实验室 北京 100083;
2. 吉林省林业科学研究院 长春 130033
• 收稿日期:2017-03-10 修回日期:2018-03-23 出版日期:2018-06-25 发布日期:2018-07-02
• 基金资助:
国家自然科学基金项目（31300552）；国家林业局948项目（2014-4-03）；中央财政林业科技推广示范资金项目（JLT[2016］1号）。
### Influence of Different Fatty Acids in Artificial Diets on Growth, Development and Fecundity of Arma chinensis
Li Xingpeng1,2, Song Liwen2, Chen Yuequ2, Li Yanan2, Zuo Tongtong2, Wu San1
1. 1. Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University Beijing 100083;
2. Jilin Provincial Academy of Forestry Sciences Changchun 130033
• Received:2017-03-10 Revised:2018-03-23 Online:2018-06-25 Published:2018-07-02
Abstract: [Objective] In this paper, the effects of different fatty acids in artificial diets on growth, development and fecundity of the predator Arma chinensis (Heteroptera:Pentatomidae) were studied to provide a basis for the development of artificial diets of natural enemy insects.[Method] Two insect-free artificial diets were used to raising A. chinensis for continuous 12 generations. The diet 1 contained palm oil (a saturated fatty acid) and the diet 2 contained flax oil (an unsaturated fatty acid). The developmental time, stage-specific survival rate, sex ratio (♀:♂), adult body mass, oviposition period, number of eggs, percent hatch as well as intrinsic rate of increase were measured by the generations of F1, F4, F8 and F12.[Result] The results showed that the effects of two types of artificial diets on developmental time and reproduction of A. chinensis varied with generations and developmental stages. The developmental time of 2nd and 3rd instar nymphs of A. chinensis was significantly different between the two artificial diets from F1 to F12. However, the developmental time of 4th and 5th instar nymphs of A. chinensis showed significant difference until to F4 (5th instar) and F8 (4th instar). The effects of the two diets on the developmental duration at each age stage of A. chinensis tended to be stable from F8. The developmental duration of 2nd and 3rd instar nymphs fed on diet 1 was shorter than that of those on diet 2, but the developmental time of 4th and 5th instar nymphs fed on diet 1 was longer than those on diet 2. Thus, diet 1 was more beneficial to the early development of nymphs, while diet 2 was better for the later development of nymphs. The egg, 1st nymph, total development (only significant difference in F1) and life span were not significantly different between two types of artificial diets. Similar to the development, the effect of the diet on mortality of 2nd instar to 5th instar nymphs and emergency rate were not significant in F1. Until to F4, the mortality of 2nd and 3rd instar nymphs and emergency rate fed on diet 1 were lower than those on diet 2, while the mortality of 4th and 5th instar nymphs fed on diet 1 were higher than that on diet 2. There were no significant differences in mortality of 1st instar nymphs and eggs hatchability in each generation between the two diets. The adult body mass of male and female, and female MRGR(mean relative growth rate) fed on diet 1 were significantly lower than those on diet 2 until to F8. The fertility of A. chinensis fed on diet 1 was significantly higher than that on diet 2 from F4 to F12. The intrinsic growth rate and population doubling time of A. chinensis fed on diet 1 were better than diet 2 from F1 to F8, however, the difference in intrinsic growth rate and population doubling time between the two diets decreased with the increase of generations. Diet2 was better than diet1 in F12. The other fecundity indexes of A. chinensis (except for sex ratio of F1) fed on diet 1 and diet 2 were not significantly different.[Conclusion] The artificial diet containing saturated fatty acids (diet 1) can significantly shorten the developmental time, reduce mortality of young nymphs, and increase the female fertility rate of Arma chinensis, but the unsaturated fatty acid in the artificial diet (diet 2) is more suitable for the growth and development of old nymphs, improving the adult rate and the population growth rate of A. chinensis. Therefore, those results suggest that we should prepare the artificial feed according to the specific growth stage of feeding insects by adding or reducing the key nutrients at different stages of insect development, to achieve the best effect during the continuous rearing of natural enemy insects in future research and reproduction. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3141908645629883, "perplexity": 8631.678109613349}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764499829.29/warc/CC-MAIN-20230130201044-20230130231044-00325.warc.gz"} |
https://studydaddy.com/question/ancient-traditions-of-islamic-culture-have-evolved-to-reflect-the-needs-of-moder | QUESTION
# Ancient Traditions of Islamic Culture Have Evolved To Reflect the Needs of Modern Women
History
Historically, women have been subjugated under men in Islamic cultures. However, proponents of Islam have often cited some Islamic attitudes and traditions that might seem oppressive from a western perspective as protective, or even empowering, for women. Marriage law, polygamy, and the traditional Islamic dress or hijab have all been cited as liberating for Islamic women.
Take a look at this website and think about these issues from an Islamic perspective, and from a western one:
http://www.jannah.org/sisters/
What do you think about the arguments presented here? Do you think the ancient traditions of Islamic culture have evolved to reflect the needs of modern women?
Tutor has posted answer for $10.00. See answer's preview$10.00 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3652835488319397, "perplexity": 5518.17993552641}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-13/segments/1521257647146.41/warc/CC-MAIN-20180319194922-20180319214922-00101.warc.gz"} |
https://www.gradesaver.com/textbooks/math/algebra/elementary-and-intermediate-algebra-concepts-and-applications-6th-edition/chapter-4-polynomials-4-4-addition-and-subtraction-of-polynomials-4-4-exercise-set-page-260/42 | ## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)
$-a^2+3a$
Removing the grouping symbols, then the given expression, $(a^2-3a-2)-(2a^2-6a-2)$, is equivalent to \begin{array}{l} a^2-3a-2-2a^2+6a+2 .\end{array} By combining like terms, then \begin{array}{l} (a^2-2a^2)+(-3a+6a)+(-2+2) \\\\= -a^2+3a+0 \\\\= -a^2+3a .\end{array} | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9979923963546753, "perplexity": 14601.966000026016}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-24/segments/1590348509972.80/warc/CC-MAIN-20200606031557-20200606061557-00595.warc.gz"} |
http://www.numdam.org/articles/10.1051/cocv:2002050/ | Local controllability of a 1-D tank containing a fluid modeled by the shallow water equations
ESAIM: Control, Optimisation and Calculus of Variations, Tome 8 (2002), pp. 513-554.
We consider a 1-D tank containing an inviscid incompressible irrotational fluid. The tank is subject to the control which consists of horizontal moves. We assume that the motion of the fluid is well-described by the Saint-Venant equations (also called the shallow water equations). We prove the local controllability of this nonlinear control system around any steady state. As a corollary we get that one can move from any steady state to any other steady state.
DOI : https://doi.org/10.1051/cocv:2002050
Classification : 76B75, 93B05, 76B15, 35F30
Mots clés : controllability, hyperbolic systems, shallow water
@article{COCV_2002__8__513_0,
author = {Coron, Jean-Michel},
title = {Local controllability of a {1-D} tank containing a fluid modeled by the shallow water equations},
journal = {ESAIM: Control, Optimisation and Calculus of Variations},
pages = {513--554},
publisher = {EDP-Sciences},
volume = {8},
year = {2002},
doi = {10.1051/cocv:2002050},
zbl = {1071.76012},
mrnumber = {1932962},
language = {en},
url = {http://www.numdam.org/articles/10.1051/cocv:2002050/}
}
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PB - EDP-Sciences
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UR - https://doi.org/10.1051/cocv:2002050
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ID - COCV_2002__8__513_0
ER -
Coron, Jean-Michel. Local controllability of a 1-D tank containing a fluid modeled by the shallow water equations. ESAIM: Control, Optimisation and Calculus of Variations, Tome 8 (2002), pp. 513-554. doi : 10.1051/cocv:2002050. http://www.numdam.org/articles/10.1051/cocv:2002050/
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[2] J.-M. Coron, Contrôlabilité exacte frontière de l'équation d'Euler des fluides parfaits incompressibles bidimensionnels. C. R. Acad. Sci. Paris 317 (1993) 271-276. | Zbl 0781.76013
[3] J.-M. Coron, On the controllability of 2-D incompressible perfect fluids. J. Math. Pures Appl. 75 (1996) 155-188. | MR 1380673 | Zbl 0848.76013
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[5] J.-M. Coron and A. Fursikov, Global exact controllability of the 2D Navier-Stokes equations on a manifold without boundary. Russian J. Math. Phys. 4 (1996) 429-448. | Zbl 0938.93030
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[13] Th. Horsin, On the controllability of the Burgers equation. ESAIM: COCV 3 (1998) 83-95. | Numdam | MR 1612027 | Zbl 0897.93034
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https://www.bankofcanada.ca/profile/gert-peersman/ | # Gert Peersman
Show all
## Staff Working Papers
### Time-Varying Effects of Oil Supply Shocks on the U.S. Economy
Staff Working Paper 2012-2
We use vector autoregressions with drifting coefficients and stochastic volatility to investigate how the dynamic effects of oil supply shocks on the U.S. economy have changed over time. We find a substantial decline in the short-run price elasticity of oil demand since the mid-eighties.
Content Type(s): Staff Research, Staff Working Papers JEL Code(s): E, E3, E31, E32, Q, Q4, Q43
### The Role of Time-Varying Price Elasticities in Accounting for Volatility Changes in the Crude Oil Market
Staff Working Paper 2011-28
There has been a systematic increase in the volatility of the real price of crude oil since 1986, followed by a decline in the volatility of oil production since the early 1990s. We explore reasons for this evolution. We show that a likely explanation of this empirical fact is that both the short-run price elasticities of oil demand and of oil supply have declined considerably since the second half of the 1980s.
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http://forio.com/about/labs/julia-studio/tutorials/advanced/1/ | #### Introduction
Julia's mathematical syntax and support for linear algebra constructs makes it an ideal language for scientific computing.
In this problem, we will investigate the space flight of the failed Apollo 13 mission, using Julia to simulate the system of differential equations that govern the motion of the spacecraft.
Problem and code adapted from the online course, Differential Equations in Action, taught by professor Jörn Loviscach
#### Background
For those of you who are unfamiliar with the story of Apollo 13, it was the seventh manned mission to the moon, and took place during April, 1970. Their mission was to land on the moon and explore a region of the moon's surface called the Fra Mauro formation. Two days and 200,000 miles after launch, disaster struck.
After turning on the hydrogen and oxygen tank stirring fans, the crew heard a loud explosion, which was the sound of the number-2 oxygen tank blowing up. Damage to the service module would have made a safe return from a moon landing impossible, so Houston decided to abort the mission.
There were two options for safe return. The quickest route would have been a direct trajectory, essentially slowing down and falling back to earth. However, this required jettisoning the Lunar Module, which would have prevented the crew from landing safely. Instead NASA chose a circumlunar route, which would "slingshot" the astronauts around the moon, using the moon's gravity to send the spacecraft back towards earth.
Prior to the oxygen tank explosion, the mission crew had just completed a burn that would slow them down so they could enter the moon's atmosphere and land on the surface. With the landing aborted, the crew had to initiate another burn that would speed them up and carry them around the back of the moon.
Our task, as NASA engineers, is to determine the amount of boost to give the spaceship so that it will return home safely.
#### Physics
Before we can start programming the simulation, we must first understand the basic physics that govern the system.
Let's first classify the problem in terms of Newtonian mechanics. There are three bodies in the simulation: the Earth, the Moon, and the Command Module. The moon is in orbit around the earth, and the command module is a projectile between the two. During its flight, the command module will experience forces due to gravity from both bodies, which will induce an acceleration. Let's examine Newton's law of gravitation (and his second law of motion) to see how this will effect the motion of the command module.
$\overrightarrow{F_G} = G\frac{M_1 M_2}{|d|^2}\hat{d}$
This describes the gravitational force between any two bodies, where $M_1$ and $M_2$ are their masses. $|d|$ represents the distance between them and $\hat{d}$ represents the unit vector that points from on body to the other. $G$ is the gravitational constant. This is the general expression. For our problem, we can use known masses for the earth and the moon to describe the gravitational force exerted by either body on the spacecraft:
$\overrightarrow{F_E} = G\frac{M_E M_S}{|d_E|^2}\hat{d_E} \\ \overrightarrow{F_M} = G\frac{M_M M_S}{|d_M|^2}\hat{d_M}$
Where $M_E$, $M_M$, and $M_S$ are the masses of the earth, moon, and spacecraft, respectively, and $d_E$ and $d_M$ are the distances (with associated unit vectors) between the spacecraft and the earth and the moon.
The total force on the spacecraft at any instant is the sum of all forces acting on it, which we will assume to be the sum of the gravity from the earth and the moon:
$\overrightarrow{F_T} = \overrightarrow{F_E} + \overrightarrow{F_M} = G M_S(\frac{M_E}{|d_E|^2}\hat{d_E} + \frac{M_M}{|d_M|^2}\hat{d_M})$
We know from Newton's second law that the force experienced by a body is equivalent to the product of its mass and the acceleration on the body.
$F = ma \\ a = \frac{F}{m}$
This allows us to express the acceleration experienced by the spacecraft in terms of known constants and one dependent variable, namely, the position of the spacecraft relative to the moon and the earth.
$\overrightarrow{a_S} = G(\frac{M_E}{|d_E|^2}\hat{d_E} + \frac{M_M}{|d_M|^2}\hat{d_M})$
We will assume that the position of the earth is constant, at the origin. The moon, however, moves periodically around the earth in the following fashion (using cartesian coordinates):
$\overrightarrow{x_M}(t) = $
Where $R$ is the radius of the moon's orbit, which we will treat as constant, $T$ is the period of the moon's orbit, and $\phi$ is the phase angle of the orbit, or the initial angular position of the earth relative to the positive x-axis. $t$ is in seconds.
We can now express a system of linear differential equations:
$\frac{d^2}{dt^2}\overrightarrow{x}(t) = G(\frac{M_E}{|d_E|^2}\hat{d_E} + \frac{M_M}{|d_M|^2}\hat{d_M}) \\ \overrightarrow{d_E} = \overrightarrow{x}(t) - \overrightarrow{origin} \\ \overrightarrow{d_M} = - \overrightarrow{x}(t)$
#### Constants
Let's get started. Open Julia Studio and create a new folder, called Apollo. Create a new file within the project folder called main.jl and then create another new file called constants.jl
It's convention to name constants with all uppercase letters in Julia. It's also convention to name variables with underscores between logical separation points. We precede the definition of a constant with the keyword const, which instructs the compiler that this variable is immutable. It also treats the constant as a global variable, without the performance hit you incur by using globals. We will define the constants in a module and export them. We can then use them by using the module name.
Let's enter the following constants:
# constants.jl
module constants
export ME, RE, G, MM, RM, MCM, DISTANCE_TO_MOON, MOON_PERIOD, MOON_INITIAL_ANGLE, ORIGIN
export TOTAL_DURATION, MARKER_TIME, TOLERANCE, INITIAL_POSITION, INITIAL_VELOCITY
const ME = 5.97e24 # Mass of earth in kg
const RE = 6.378e6 # Radius of earth in m (at equator)
const G = 6.67e-11 # Gravitational constant in m3 / kg s2
const MM = 7.35e22 # Mass of moon in kg
const RM = 1.74e6 # Radius of moon in m
const MCM = 5000. # Mass of command module in kg
const DISTANCE_TO_MOON = 400.5e6 # m (actually, not at all a constant)
const MOON_PERIOD = 27.3 * 24.0 * 3600. # s
const MOON_INITIAL_ANGLE = pi / 180. * -61. # Radians
const ORIGIN = [0., 0.] # Vector that represents the origin
const TOTAL_DURATION = 12. * 24. * 3600.# s
const MARKER_TIME = 0.5 * 3600. # (used in error correction) s
const TOLERANCE = 100000. # (used in error correction) m
const INITIAL_POSITION = [-6.701e6, 0.] # Initial vector for the spacecraft in m
const INITIAL_VELOCITY = [0., -10.818e3] # Initial velocity for spacecraft in m/s
end
In main.jl, load in these constants:
# main.jl
using constants
#### Julia's Type System
Let's take a moment to talk about types in Julia. For a detailed description, we recommend reading the material in the Julia Manual, but we'll address some of it here.
In addition to the concrete types that the language defines for you, Julia allows you to express composite types. You can think of a composite type as a struct in C, or an object, or a template, depending on what languages you are familiar with. The key difference between concrete types in Julia and objects in other languages is that concrete types do not have methods associated with them. This functionality can be achieved, as we will see later, but not by defining methods on types.
Let's start with an example. First, create a file called types.jl. This is where we will define all of our types, again in a module. This simulation involves three bodies, so it makes sense to create a Body type:
# types.jl
module types
type Body{T}
mass::T
velocity::Vector{T}
position::Vector{T}
end
Let's talk about what's going on here. On the first line, we use the keyword type, followed by Body{T}. This is an example of a parametric type, where we can pass in a type, e.g. Float64 as a parameter in the type instantiation, and that type will be applied to each of the named fields. Here, we specify that each body will have 4 such named fields: mass, which will inherit the type passed in, velocity, which will be a vector (a one 1xN array) with values of type, T, radius, which will be of type, T, and position, another vector whose values are of type, T. The :: operater is a type assertion, asserting that those fields must be of the specified type.
Here's how we might instantiate a new Body:
# With explicit type parameter
earth = Body{Float64}(ME, [0., 0.], RE, ORIGIN)
# Without explicit type parameter
earth = Body(ME, [0., 0.], RE, ORIGIN)
We can then reference each of its attributes using the normal dot notation: earth.mass, etc.
Let's define a few more types:
# types.jl
module types
export Body, Moon, Command_Module, EarthMoonSystem
type Body{T}
mass::T
velocity::Vector{T}
position::Vector{T}
end
typealias Moon Body # Create a new type, Moon, that has all the
# attributes of Body, but is treated as its own type
type Command_Module{T}
mass::T
velocity::Vector{T}
position::Vector{T}
end
type EarthMoonSystem # This is a non-parametric type, since it doesn't take any arguments
time::Float64
earth::Body # See what we did there?
moon::Moon # Now we can do type assertion with our composite types
command_module::Command_Module
end
end
In these lines, we use the typealias keyword to create two new types, one for the moon, and one for the command module, that have the same named attributes and parameters as Body, but have different names. We will see why this is important later. Use this module in main.jl
# main.jl
using constants
using types
#### Building a simulation
Let's instantiate some new bodies in main.jl, and create a function, simulate, that will be our interface for running the simulation.
# main.jl
using constants
using types
# Initialization of our bodies
earth = Body(ME, [0.0, 0.0], RE, ORIGIN)
moon = Moon(MM, [0., 0.], RM, moon_position(0.0))
command_module = Command_Module(MCM, INITIAL_VELOCITY, 5.0, INITIAL_POSITION)
world = EarthMoonSystem(0.0, earth, moon, command_module)
function simulate()
current_time = 1.
while current_time <= TOTAL_DURATION
update(world, current_time)
current_time += 1.
end
end
In this function, we initialize the simulation time at 1, and update the world once a second until we reach the end of the simulation.
Now we must define the update method. Create a new file called system.jl which will contain all the functions for instances of EarthMoonSystem types. What do we want this function to do? We want it to update the status of all the bodies within it.
# system.jl
function update(me::EarthMoonSystem, time::Float64)
# me is a reference to this instance of EarthMoonSystem
me.time = time # Explicitly set the time on the system
update(me.moon, time) # Update the moon
update(me.command_module, time) # Update the command_module
return me # Return the system
end
Wait a second. Are we calling update again? Does that mean this is a recursive function? Shouldn't we name those functions something like update_moon and update_command_module? No, because of Julia's adherence to a pattern called multiple dispatch.
Multiple dispatch allows us to define functions as collections of methods, where each method is defined for a specific combination of types. Julia calls whichever function method best applies to the types of the arguments. Here is an example. Let's say we define a function, call_person, that calls a specific person:
type Person
name::String
end
function call_person(person)
print("Hello $person.name") end mom = Person("mom") call_person(mom) In this example, we define a Person type, and a function for calling a person, which says hello to that person. Now let's take it another step further to illustrate how mutliple dispatch works: type Person name::String end typealias Mom Person typealias Boss Person typealias Doctor Person function call_person(person) print("Hello$person.name")
end
function call_person(person::Mom)
print("I love you, mom")
end
function call_person(person::Boss)
print("Sorry I'm late, \$person.name")
end
function call_person(person::Doctor)
print("What's up, doc?")
end
doc = Doctor("Rich")
call_person(doc)
Now we've extended the call_person function with three more methods. The correct version of call_person will be called, depending on the type of arguments. If the type of the arguments do not match any of those specified, the first method will be called, since no type assertions are used there. In this case, we create a new Doctor and then call call_person. The output of this code should be, "What's up, Doc?".
Now that it's clear why we can have three different update methods, let's write them. Create two new files, command-module.jl and moon.jl.
In each, add the following method:
# command-module.jl
function update(me::Command_Module, time::Float64)
return me
end
# moon.jl
function update(me::Moon, time::Float64)
return me
end
Now let's focus on the moon. In moon.jl, enter the following.
# moon.jl
function moon_position(time::Float64)
moon_angle = MOON_INITIAL_ANGLE + 2.0pi * time / MOON_PERIOD
x::Float64 = DISTANCE_TO_MOON * cos(moon_angle)
y::Float64 = DISTANCE_TO_MOON * sin(moon_angle)
return [x, y]
end
function update(me::Moon, time)
me.position = moon_position(time)
me
end
Now the update method calls the moon_position function, which returns the x and y coordinates of the moon as a vector.
Now, in command-module.jl:
# command-module.jl
function acceleration(time::Float64, pos::Vector{Float64})
moon_pos = moon_position(time) # Get the moon's position at this time
distance_from_earth = pos # Earth is at the origin
distance_to_moon = pos - moon_pos # Distance between command module and moon
mag_e = norm(distance_from_earth) # Get the magnitude of this vector
mag_m = norm(distance_to_moon)
return -G * (ME * distance_from_earth / mag_e^3 + MM * distance_to_moon / mag_m^3)
end
function update(me::Command_Module, time::Float64)
a = acceleration(time, me.position) # Calculate the acceleration on the module
# Using Euler's method
me.position += me.velocity # Increment position vector by velocity vector
me.velocity += a # Add acceleration vector to velocity vector
me
end
This code use's Euler's method to solve the system of differential equations. First, we calculate the acceleration on the command module based on its distance from the earth and the moon. Since velocity the the rate of change in position, we can add it to current position to get a new position. Since acceleration is the rate of change of velocity, we add it to velocity for use in the next step. If we use small enough steps, this numerical solution approximates the analytical solution to the system of equations. Notice how easy it is to add vectors in Julia. All normal mathematical operations work on arrays.
If we include these files in main.jl, and add a call to our simulate() function, we should have a running simulation!
#### Viewing the Results
We want to see the results, right? Let's create some variables to hold the results. Somewhere in the function body of the simulate function, before the start of the loop, create a new vector: position_list = Vector{Float64}[]. This variable is a vector that will hold all the position vectors. Now, in the body of the loop, after calling update, add the following line: push!(position_list, copy(world.command_module.position)).
Now, after the conclusion of the loop, return the value of position_list. We will use Julia's writecsv method to output our results to a csv file:
# in main.jl, after simulate() function
@time pos = simulate() # get the results, show elapsed time
writecsv("output.csv", pos) # write the output to a csv file
The entire file should look like this:
# main.jl
using constants
using types
include("physics.jl")
include("moon.jl")
include("command-module.jl")
include("system.jl")
# Initialization of our bodies
earth = Body(ME, [0.0, 0.0], RE, ORIGIN)
moon = Moon(MM, [0., 0.], RM, moon_position(0.0))
command_module = Command_Module(MCM, INITIAL_VELOCITY, 5.0, INITIAL_POSITION)
world = EarthMoonSystem(0.0, earth, moon, command_module)
function simulate()
position_list = Vector{Float64}[] # m
current_time = 1.
while current_time <= TOTAL_DURATION
update(world, current_time)
push!(position_list, copy(world.command_module.position))
current_time += 1
end
return position_list
end
@time pos = simulate()
writecsv("output.csv", pos)
If we run this, notice that it takes a long time and generates a lot of data. If we graph the data in Excel the output looks wrong, because Euler's method leads to a large amount of error in the calculations. If we substitute another method called Heun's method, and use an adaptive step size instead of 1, then we can greatly reduce the error in our calculations. Here's how we can implement it.
First, change update for command_module to look like this:
# in command_module.jl
function update(me::Command_Module, time::Float64, h::Float64)
acceleration0 = acceleration(time, me.position) # Get acceleration at current time
velocityE = me.velocity + h * acceleration0 # Calculate Euler's velocity,
# Accounting for the adaptive step size
positionE = me.position + h * me.velocity # Calculater Euler's position
# Heun's method looks ahead to the next step and averages the two values
velocityH = me.velocity + h * 0.5 * (acceleration0 + acceleration(time + h, positionE))
positionH = me.position + h * 0.5 * (me.velocity + velocityH)
# We will use the Heun's values
me.velocity = velocityH
me.position = positionH
# Store these on the command_module so the simulation can access them
me.positionH = positionH
me.velocityH = velocityH
me.positionE = positionE
me.velocityE= velocityE
me
end
We now have to modify the Command_Module type to include these new named fields:
# in types.jl
type Command_Module{T}
mass::T
velocity::Vector{T}
position::Vector{T}
positionE::Vector{T}
positionH::Vector{T}
velocityE::Vector{T}
velocityH::Vector{T}
end
And we modify the initialization code in main.jl:
# in main.jl
command_module = Command_Module(MCM, INITIAL_VELOCITY, 5.0, INITIAL_POSITION, INITIAL_POSITION, INITIAL_POSITION, INITIAL_VELOCITY, INITIAL_VELOCITY)
You'll also notice that the update method in command_module.jl now takes an additional argument, h, which we need to pass in. This is the step size to use. The simulation will adjust the step size depending on the error we generate between Heun's values and Euler's values, hence the name adaptive step size. Smaller values of h give more accurate results, but take longer to run. Larger values generate less accurate results, but in fewer steps. We have arbitrarily set a TOLERANCE in constants.jl to 100,000 m, but you can experiment with different values.
Because we've modified the update method in command-module.jl, make sure to modify each update call to include h as the third argument. This happens twice: in main.jl: update(world, current_time, h), and also in system.jl: update(me.command_module, time, h).
Now, back in main.jl, let's initialize step size with a value of 0.1 right before the start of the loop. Also create a variable called h_new to store the adapted step size.
# in main.jl, in simulate() function
position_list = Vector{Float64}[]
current_time = 1.
h = 0.1 # s, set as initial step size right now but will store current step size
h_new = h # s, will store the adaptive step size of the next step
In place of current_time += 1, we will insert the following:
# in main.jl, in simulate() function
positionE = world.command_module.positionE
positionH = world.command_module.positionH
velocityE = world.command_module.velocityE
velocityH = world.command_module.velocityH
error_amt = norm(positionE - positionH) + TOTAL_DURATION * norm(velocityE - velocityH)
h_new = min(0.5 * MARKER_TIME, max(0.1, h * sqrt(TOLERANCE / error_amt))) # Restrict step size to reasonable range
current_time += h
h = h_new
Let's examine more closely what we're doing. When we calculate error_amt, we are getting a normalized error vector in our current position and adding in our long term error, which is our current normalized error vector in position, multiplied by the total duration of the simulation. This vector explains how much error we expect in our calculations given the current step size.
The following line picks a new step size, h_new, based on the ratio of our tolerance to our projected error.
We then increment current time by step size, and set the step size for the next iteration to be our new step size. Here's a snapshot of what main.jl should look like now:
# main.jl
using constants
using types
include("physics.jl")
include("moon.jl")
include("command-module.jl")
include("system.jl")
# initialization of our bodies
earth = Body(ME, [0.0, 0.0], RE, ORIGIN)
moon = Moon(MM, [0., 0.], RM, moon_position(0.0))
command_module = Command_Module(MCM, INITIAL_VELOCITY, 5.0, INITIAL_POSITION, INITIAL_POSITION, INITIAL_POSITION, INITIAL_VELOCITY, INITIAL_VELOCITY)
world = EarthMoonSystem(0.0, earth, moon, command_module)
function simulate()
position_list = Vector{Float64}[]
current_time = 1.
h = 0.1 # s, set as initial step size right now but will store current step size
h_new = h # s, will store the adaptive step size of the next step
while current_time <= TOTAL_DURATION
update(world, current_time, h)
positionE = world.command_module.positionE
positionH = world.command_module.positionH
velocityE = world.command_module.velocityE
velocityH = world.command_module.velocityH
error_amt = norm(positionE - positionH) + TOTAL_DURATION * norm(velocityE - velocityH)
h_new = min(0.5 * MARKER_TIME, max(0.1, h * sqrt(TOLERANCE / error_amt))) # Restrict step size to reasonable range
current_time += h
h = h_new
push!(position_list, copy(world.command_module.position))
end
return position_list
end
@time pos = simulate()
writecsv("output.csv", pos)
#### Save Us!
So now, we can finally answer the question about how to save the astronauts. If we run the program and plot the output, we should see that the astronauts will return to the exact position they started at, right on earth:
In actuality, the astronauts had already fired one burn, called the mcc2 burn, which reduced their speed by about 7.04 meters/second. This is just enough to encourage a slow descent to the Lunar surface.
We can program that into the model by checking the time. If the time is correct, reduce velocity and set a flag to prevent the burn from firing again. In main.jl, in the simulate() method right after the update call, add this:
# in main.jl, in simulate() function
if !mcc2_burn_done && current_time >= 101104
println("mcc2_burn fired")
world.command_module.velocity -= 7.04 / norm(world.command_module.velocity) * world.command_module.velocity
mcc2_burn_done = true
end
Make sure to initialize this variable with a value of false.
Here is what the trajectory would look like if the astronauts had fired the mcc2 burn and done nothing else (assuming they did not crash into the moon!):
Now, our challenge is to fire a burn just large enough to save the astronauts from crashing into the moon, but small enough to prevent the astronauts from careening off into space forever. Add some code for a second burn (remember to initialize it as false). Also initialize a value for boost. Set it to 0 initially:
# in main.jl, in simulate() function
if !dps1_burn_done && current_time >= 212100
println("corrective_burn fired")
world.command_module.velocity += boost / norm(world.command_module.velocity) * world.command_module.velocity
dps1_burn_done = true
end
Now experiment with different values of boost, seeing how it affects the trajectory of the spacecraft.
#### Conclusion
Here are some comparisons of different values of boost
As you can see here, a boost of about 10 m/s seems about right. | {"extraction_info": {"found_math": true, "script_math_tex": 21, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5770523548126221, "perplexity": 2291.103973057913}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-44/segments/1476988719192.24/warc/CC-MAIN-20161020183839-00554-ip-10-171-6-4.ec2.internal.warc.gz"} |
https://quantumcomputing.stackexchange.com/questions/21610/how-does-one-get-the-right-counts-for-the-measurement-of-a-single-qubit-in-the-p | # How does one get the right counts for the measurement of a single qubit in the presence of noise with qiskit?
I am using a single qubit in the IBM quantum lab running on ibm_armonk and it is simulated with real noise, however when I try to measure out a state where the coefficient of the 0 state is less than 0.1 I get the wrong counts. I always get the result that there were roughly 1/10 of the counts in the 0 state and 9/10 in the 1 state (for example, if I try to initialize the state so that the probability of 0 is 0.01). I used 8192 shots but when I try to repeat the experiment I get the same results. This doesn't make sense to me because I would expect the effect of noise to lead to a more Gaussian type of distribution around the average, so after enough measurements the counts should lead to the average value. My code involves the following:
initial_state = [0.1,math.sqrt(0.9)] # my code is a little different here, but this
# should give an idea of the numbers I am
# using
circuit.initialize(initial_state,0)
circuit.measure(0,0)
job = execute(circuit,device,shots=8192)
result = job.result()
result = result.get_counts(circuit)
print(counts)
• Your observations are consistent with what is called "measurement" or "readout" error (as opposed to other types like "gate error" or "thermal relaxation"). I could try to answer your question, but it is a bit vague at the moment. Can you make it more specific? Oct 20 at 18:00
• Is there any way to reduce the measurement error? By measurement error I assume you mean not the effect of noise changing the overall state of the qubit but the noise making it difficult to distinguish the 0 and 1 states, so would there be any way to deal with this problem? Oct 20 at 21:39
• Yes - if you know how likely a |0⟩ gets read as 1 and a |1⟩ gets read as 0, you can reverse the statistics in a classical post-processing step. See this tutorial: qiskit.org/documentation/tutorials/noise/… Oct 21 at 0:11 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7968456149101257, "perplexity": 326.12807569042064}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964362918.89/warc/CC-MAIN-20211203182358-20211203212358-00348.warc.gz"} |
http://newartisans.com/2013/05/three-examples-of-problems-with-lazy-io/ | Lost in Technopolis
by John Wiegley
# Three examples of problems with Lazy I/O
Posted by John Wiegley on May 13, 2013 with labels:
### Problem 1: The source of exceptions is obscured
main = getArgs >>= readFile . head >>= print . length
Even though length is a pure function, this is where the I/O will happen (lazily), which means that is where any exceptions relating to I/O will get raised. Pure code should avoid raising exceptions, which this example violates.
### Problem 2: Sharing may cause file contents to remain in memory
main = getArgs >>= readFile . head >>= print . (length . words &&& length)
Because of the way that lazy I/O reads in strings, this line of code will cause the entire contents of the file to be loaded into memory by the call to either length or words, and then it will stay in memory to be handled by the other call to length. You would expect it to process the input at the very least one line at a time, to avoid exhausting memory on very large files.
NOTE: It has been pointed out that this is not really a problem with Lazy I/O, but with laziness in general. The only real way, then, in which an iteratee-type library helps here is that it’s more typical to connect sources and sinks directly together, than to read all the data from a source at one time, and then hand it to two sinks that way. So the problem there is not solved either, it’s just less common to the idiom.
### Problem 3: File handles are not closed when you might expect
main = getArgs >>= mapM_ (readFile >=> print . length)
If getArgs returns N files, Haskell will open N file handles, rather than one at a time as you might expect, meaning that running this in a very large directory may exhaust system resources.
### Conclusion: Use conduit/pipes/io-streams library to avoid surprises
Lazy I/O is great for prototypical simple examples, but for serious code these problems can be hard to track down – and are eliminated by a library such as conduit. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.21673542261123657, "perplexity": 1832.666581945431}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-49/segments/1416400379404.25/warc/CC-MAIN-20141119123259-00042-ip-10-235-23-156.ec2.internal.warc.gz"} |
https://link.springer.com/article/10.1007%2Fs10586-017-1389-z | Cluster Computing
, Volume 22, Supplement 3, pp 7359–7368
# No projection in the residual network
• Huanglu Wen
• Liejun Wang
Article
## Abstract
Convolution networks continue to create state-of-the-art results in computer vision, and the Residual Network is an important milestone. In the original residual network, 1 $$\times$$ 1 convolution with stride 2 is used as the projection to do the linear transformation between feature maps of different sizes and different number of channels. This projection structure does not satisfy the concept of residual learning and is not able to use all of the input information. We propose a method which will make the Residual Network completely free of this structure and realize what shortcut connections should be. Compared with the original Residual Network, our models achieve higher learning efficiency and higher average performance with fewer parameters and lower computational complexity on CIFAR-10/100.
## Keywords
Convolution networks Residual network Shortcut connection CReLU ELU
## Notes
### Acknowledgements
This work is supported by Chinese National Natural Science Foundation (Program No. 61471311 & No. 61771416).
## References
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Krizhevsky, A., Sutskever, I., Hinton, G.E.: Imagenet classification with deep convolutional neural networks. Commun. ACM 60(6), 84–90 (2017)
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Simonyan, K., Zisserman, A.: Very deep convolutional networks for large-scale image recognition. In: ICLR (2015)Google Scholar
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Szegedy, C., Liu, W., Jia, Y.Q., Sermanet, P., Reed, S., Anguelov, D., Erhan, D., Vanhoucke, V., Rabinovich, A.: Going deeper with convolutions. In: Proceedings of IEEE Conference on Computer Vision and Pattern Recognition (CVPR), pp. 1–9 (2015)Google Scholar
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He, K.M., Zhang, X.Y., Ren, S.Q., Sun, J.: Deep residual learning for image recognition. In: Proceedings of 29th IEEE Conference on Computer Vision and Pattern Recognition Workshops (CVPRW) (2016)Google Scholar
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Zagoruyko, S., Komodakis, N.: Wide residual networks. In: Proceedings of British Machine Vision Conference (2016)Google Scholar
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He, K., Zhang, X., Ren, S., Sun, J.: Identity mappings in deep residual networks. In: Proceedings of European Conference on Computer Vision (ECCV) (2016)Google Scholar
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Veit, A., Wilber, M., Belongie, S.: Residual networks behave like ensembles of relatively shallow networks. In: Proceedings of 30th Annual Conference on Neural Information Processing Systems (NIPS) (2016)Google Scholar
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Shang, W., Sohn, K., Almeida, D., Lee, H.: Understanding and improving convolutional neural networks via concatenated rectified linear units. In: Proceedings of 33rd International Conference on Machine Learning (ICML) (2016)Google Scholar
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Glorot, X., Bordes, A., Bengio, Y.: Deep sparse rectifier neural networks. In: Proceedings of 14th International Conference on Artificial Intelligence and Statistics (AISTATS) (2011)Google Scholar
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Clevert, D.A., Unterthiner, T., Hochreiter, S.: Fast and accurate deep network learning by exponential linear units (ELUs). In: ICLR (2016)Google Scholar
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Ioffe, S., Szegedy, C.: Batch normalization: Accelerating deep network training by reducing internal covariate shift. In: Proceedings of 32nd International Conference on Machine Learning (ICML) (2015)Google Scholar
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Nesterov, Y.: Gradient methods for minimizing composite functions. Math. Program. 140(1), 125–161 (2013)
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Hinton, G.E., Srivastava, N., Krizhevsky, A., Sutskever, I., Salakhutdinov, R.R.: Improving neural networks by preventing co-adaptation of feature detectors. Comput. Sci. 3(4), 212–223 (2012)Google Scholar
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Krizhevsky, A., Hinton, G.: Learning multiple layers of features from tiny images. Tech Report (2009)Google Scholar | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7227818369865417, "perplexity": 10587.709546489305}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496668772.53/warc/CC-MAIN-20191116231644-20191117015644-00200.warc.gz"} |
http://pipingdesigner.co/index.php/properties/fluid-mechanics/550-saturated-vapor-pressure | # Saturated Vapor Pressure
Written by Jerry Ratzlaff on . Posted in Fluid Dynamics
Saturated vapor pressure, abbreviated as $$e_s$$, is the pressure applied by air that is mixed with water vapor, at a given temperature, at its maximum saturation point.
### Saturated Vapor Pressure formula
$$\large{ e_s = 100 \; \frac{RH}{e} }$$
Where:
$$\large{ e_s }$$ = saturated vapor pressure
$$\large{ e }$$ = actual vapor pressure
$$\large{ RH }$$ = relative humidity | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9640741348266602, "perplexity": 3497.340410220904}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-29/segments/1593655921988.66/warc/CC-MAIN-20200711032932-20200711062932-00423.warc.gz"} |
https://proofwiki.org/wiki/Definition:Ordered_Quadruple | # Definition:Ordered Tuple as Ordered Set/Ordered Quadruple
Jump to navigation Jump to search
## Definition
The ordered quadruple $\tuple {a, b, c, d}$ of elements $a$, $b$, $c$ and $d$ is defined either as the ordered pair:
$\tuple {a, \tuple {b, c, d} }$
or:
$\tuple {\tuple {a, b, c}, d}$
where $\tuple {a, b, c}$ and $\tuple {b, c, d}$ are themselves ordered triples.
Whichever definition is chosen does not matter much, as long as it is understood which is used. And even then, the importance is limited. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9944044351577759, "perplexity": 826.4391775022393}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496667319.87/warc/CC-MAIN-20191113164312-20191113192312-00384.warc.gz"} |
http://mathhelpforum.com/calculus/91643-help-composite-rule-question.html | # Thread: help with composite rule question
1. ## help with composite rule question
Hey can anyone help me with the following question....
use the composite rule to differentiate f(x) = e^cosx+sinx
thank you
2. composite rule is another name for chain rule isn't it?
differentiate the seperate terms
so $e^{cos(x)}$ diff's to $-sin(x)(e^{cos(x)})$ using the chain rule (or composite rule (i.e. you diff the first term, then multiply by the diff of term inside brackets)) and $sin(x)$ diff's to $cos(x)$ using standard rules. then just add them together at the end
$f'(x)=-sin(e^{cos(x)})+cos(x)$ and to be more artistic you would swap them so you don't start with a negative sign.
3. if you mean
$f(x)=e^{cosx+sinx}$
$f'(x)=\left(\frac{d}{dx}(cosx+sinx)\right)e^{cosx+ sinx}$
$f'(x)=(-sinx+cosx)e^{cosx+sinx}$
5. well using the product rule of
k'(x)= f'(x)g(x) + f(x) g'(x)
and the previous equation, can i show the derivitave of the function
g(x) = (cosx + sinx - 1) e^cosx+sinx
is g'(x) = (cos^2x - sin^2x)e^cosx +sinx
6. Originally Posted by Rapid_W
composite rule is another name for chain rule isn't it?
differentiate the seperate terms
so $e^{cos(x)}$ diff's to $-sin(e^{cos(x)})$
The derivative of $e^{cos(x)}$ is -sin(x) times $e^{cos(x)}$, not -sin of $e^{cos(x)}$ as you write.
using the chain rule (or composite rule (i.e. you diff the first term, then multiply by the diff of term inside brackets)) and $sin(x)$ diff's to $cos(x)$ using standard rules. then just add them together at the end
$f'(x)=-sin(e^{cos(x)})+cos(x)$ and to be more artistic you would swap them so you don't start with a negative sign.
7. oops, missed the x out, simple error, have fixed my original post, thanks for pointing that out. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 16, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9451382160186768, "perplexity": 1665.9306727035876}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2013-48/segments/1387345758389/warc/CC-MAIN-20131218054918-00068-ip-10-33-133-15.ec2.internal.warc.gz"} |
https://www.physicsforums.com/threads/inelastic-and-elastic-collision-problems.301863/ | # Inelastic and elastic collision problems
• Start date
• #1
3
0
1. An 8 g rubber bullet was fired into a 2.5 kg pendulum bob, initially at rest, and becomes embedded in it. The pendulum rises a vertical distance of 6.0 cm.Calculate the initial speed and how much kinetic energy is lost in this collision?
2. An 8 g rubber bullet was fired into a 2.5 kg pendulum bob, initially at rest, and bounces off into the opposite direction. It rises 6.0 cm vertically. (elastic case) What is the velocity of the bob after the collision? Use conservation momentum to find the change in velocity of the bullet. Use conservation of Kinetic energy to find initial velocity of bullet and final velocity of the bullet.
I heard that I needed to use the inelastic collision and the conservation of energy equation for number 1.
0.5*mass*initial velocity^2 +mass*gravitational pull* initial height=0.5*mass*final velocity^2 +mass*gravitational pull* final height.
I triedto solve but could not because i did not know the initial velocity of the bullet and the final velocity.
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https://eckhartarnold.de/papers/2013_Simulations_as_Virtual_Experiments/index.html | # When can a Computer Simulation act as Substitute for an Experiment? A Case-Study from Chemisty
Johannes Kästner and Eckhart Arnold
When can a Computer Simulation act as Substitute for an Experiment? A Case-Study from Chemisty
Author: Johannes Kästner
Institute of Theoretical Chemistry, University of Stuttgart
Eckhart Arnold
Institute for Philosophy, University of Düsseldorf
Date: July 2013
### Abstract:
In this article we investigate with a case study from chemistry under what conditions a simulation can serve as a surrogate for an experiment. We set out with a brief discussion of the similarities and differences between simulations and experiments. There are three fundamental differences: 1) Ability (of experiments) to gather new empirical data. 2) Ability to operate directly on the target system. 3) Ability to empirically test fundamental hypotheses. Given that there are such fundamental differences it becomes an important question if and under what conditions simulations can still act as surrogate for experiments.
We investigate this question by analysing a simulation of $H_2$-formation in outer space. We find that in this case the simulation can act as a surrogate for an experiment, because there exists comprehensive theoretical background knowledge about the range of phenomena to which the investigated process belongs and because any particular modelling assumptions as, for example, on the validity of approximations, can be justified. If these requirements are met then direct empirical validation of a “virtual experiment” may even be dispensable. We conjecture that in the absence of comprehensive theoretical background knowledge direct empirical validation of “virtual experiments” remains unavoidable.
Keywords Computer Simulations, Virtual Experiments, Epistemology of Simulations, Quantum Chemistry
### Bibliographical information
Citing:
Johannes Kästner and Eckhart Arnold: When can a Computer Simulation act as Substitute for an Experiment? A Case-Study from Chemisty, on: Homepage Eckhart Arnold, 2013, https://eckhartarnold.de
BibTeX record:
@InCollection{Kaestner-Arnold2013,
Title = {When can a Computer Simulation act as Substitute for an
Experiment? A Case-Study from Chemisty},
Author = {Johannes Kästner and Eckhart Arnold},
Booktitle = {Homepage Eckhart Arnold},
Publisher = {Eckhart Arnold},
Year = {2013},
Editor = {Eckhart Arnold},
Url = {https://eckhartarnold.de/papers/2013_Simulations_as_Virtual_Experiments/
Simulations_as_Virtual_Experiments.html}
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http://www.malwareremoval.com/forum/viewtopic.php?f=11&t=7682 | Welcome to MalwareRemoval.com,
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Hello Again,
Can you please check my HJT log. I think a virus or trojan was downloaded on my computer. The names of the files that I believe are viruses are; Image001.wmz, Image003.wmz, and oledata.mso.
Thank you,
Tanya
Here is a copy of my HJT log:
Logfile of HijackThis v1.99.1
Scan saved at 10:43:22 AM, on 02/28/2006
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)
Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\svchost.exe
C:\Program Files\Windows Defender\MsMpEng.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Yahoo!\Antivirus\ISafe.exe
C:\WINDOWS\system32\cisvc.exe
C:\Program Files\Kerio\Personal Firewall 4\kpf4ss.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Kerio\Personal Firewall 4\kpf4gui.exe
C:\WINDOWS\system32\fxssvc.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Kerio\Personal Firewall 4\kpf4gui.exe
C:\WINDOWS\System32\hkcmd.exe
C:\WINDOWS\BCMSMMSG.exe
C:\Program Files\MUSICMATCH\MUSICMATCH Jukebox\mm_tray.exe
C:\Program Files\Hewlett-Packard\HP Share-to-Web\hpgs2wnd.exe
C:\Program Files\MySoftware\MyInvoices\tracker.exe
C:\Program Files\Visioneer OneTouch\OneTouchMon.exe
C:\Program Files\Yahoo!\browser\ybrwicon.exe
C:\Program Files\Yahoo!\Antivirus\CAVTray.exe
C:\Program Files\Yahoo!\Antivirus\CAVRID.exe
C:\PROGRA~1\Yahoo!\YOP\yop.exe
C:\Program Files\support.com\bin\tgcmd.exe
C:\Program Files\Dell Photo AIO Printer 962\dlbxmon.exe
C:\Program Files\Windows Defender\MSASCui.exe
C:\WINDOWS\system32\wuauclt.exe
C:\Program Files\CA\eTrust Internet Security Suite\caissdt.exe
C:\PROGRA~1\HEWLET~1\HPSHAR~1\hpgs2wnf.exe
C:\PROGRA~1\Yahoo!\browser\ycommon.exe
C:\Program Files\Dell Support\DSAgnt.exe
C:\WINDOWS\System32\dlbxcoms.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Hewlett-Packard\AiO\hp officejet v series\Bin\hpoant07.exe
C:\Program Files\Common Files\G7PS\Shared Files\Qchex\Qchex.exe
C:\Program Files\Yahoo!\Messenger\ymsgr_tray.exe
C:\PROGRA~1\HEWLET~1\AiO\Shared\Bin\hpoevm07.exe
C:\Program Files\Yahoo!\Antivirus\VetMsg.exe
C:\Program Files\Hewlett-Packard\AiO\Shared\bin\hpOSTS07.exe
C:\Program Files\Hewlett-Packard\AiO\Shared\bin\hpOFXM07.exe
C:\Program Files\Internet Explorer\IEXPLORE.EXE
C:\WINDOWS\system32\cidaemon.exe
C:\HJT\HijackThis.exe
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.comcast.net/home.html
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyServer = :0
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: (no name) - {53707962-6F74-2D53-2644-206D7942484F} - C:\Program Files\Spybot - Search & Destroy\SDHelper.dll
O3 - Toolbar: Yahoo! Toolbar - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn4\yt.dll
O4 - HKLM\..\Run: [IgfxTray] C:\WINDOWS\System32\igfxtray.exe
O4 - HKLM\..\Run: [HotKeysCmds] C:\WINDOWS\System32\hkcmd.exe
O4 - HKLM\..\Run: [BCMSMMSG] BCMSMMSG.exe
O4 - HKLM\..\Run: [MoneyStartUp10.0] "C:\Program Files\Microsoft Money\System\Activation.exe"
O4 - HKLM\..\Run: [MMTray] "C:\Program Files\MUSICMATCH\MUSICMATCH Jukebox\mm_tray.exe"
O4 - HKLM\..\Run: [Share-to-Web Namespace Daemon] C:\Program Files\Hewlett-Packard\HP Share-to-Web\hpgs2wnd.exe
O4 - HKLM\..\Run: [Tracker] C:\Program Files\MySoftware\MyInvoices\tracker.exe
O4 - HKLM\..\Run: [OneTouch Monitor] C:\Program Files\Visioneer OneTouch\OneTouchMon.exe
O4 - HKLM\..\Run: [YBrowser] C:\Program Files\Yahoo!\browser\ybrwicon.exe
O4 - HKLM\..\Run: [CaAvTray] "C:\Program Files\Yahoo!\Antivirus\CAVTray.exe"
O4 - HKLM\..\Run: [CAVRID] "C:\Program Files\Yahoo!\Antivirus\CAVRID.exe"
O4 - HKLM\..\Run: [YOP] C:\PROGRA~1\Yahoo!\YOP\yop.exe /autostart
O4 - HKLM\..\Run: [BJCFD] C:\Program Files\BroadJump\Client Foundation\CFD.exe
O4 - HKLM\..\Run: [tgcmd] "C:\Program Files\support.com\bin\tgcmd.exe" /server
O4 - HKLM\..\Run: [dlbxmon.exe] "C:\Program Files\Dell Photo AIO Printer 962\dlbxmon.exe"
O4 - HKLM\..\Run: [Windows Defender] "C:\Program Files\Windows Defender\MSASCui.exe" -hide
O4 - HKLM\..\Run: [CaISSDT] "C:\Program Files\CA\eTrust Internet Security Suite\caissdt.exe"
O4 - HKCU\..\Run: [DellSupport] "C:\Program Files\Dell Support\DSAgnt.exe" /startup
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [MSMSGS] "C:\Program Files\Messenger\msmsgs.exe" /background
O4 - HKCU\..\Run: [Yahoo! Pager] "C:\Program Files\Yahoo!\Messenger\ypager.exe" -quiet
O4 - Global Startup: HPAiODevice(hp officejet v series) - 1.lnk = C:\Program Files\Hewlett-Packard\AiO\hp officejet v series\Bin\hpoant07.exe
O4 - Global Startup: Qchex Tray Icon.lnk = C:\Program Files\Common Files\G7PS\Shared Files\Qchex\Qchex.exe
O8 - Extra context menu item: &AOL Toolbar search - res://C:\Program Files\AOL Toolbar\toolbar.dll/SEARCH.HTML
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: AOL Toolbar - {4982D40A-C53B-4615-B15B-B5B5E98D167C} - C:\Program Files\AOL Toolbar\toolbar.dll (file missing)
O9 - Extra 'Tools' menuitem: AOL Toolbar - {4982D40A-C53B-4615-B15B-B5B5E98D167C} - C:\Program Files\AOL Toolbar\toolbar.dll (file missing)
O9 - Extra button: ComcastHSI - {669B269B-0D4E-41FB-A3D8-FD67CA94F646} - http://www.comcast.net/ (file missing)
O9 - Extra button: Support - {8828075D-D097-4055-AA02-2DBFA9D85E8A} - http://www.comcastsupport.com/ (file missing)
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: Help - {97809617-3937-4F84-B335-9BB05EF1A8D4} - http://online.comcast.net/help/ (file missing)
O9 - Extra button: Real.com - {CD67F990-D8E9-11d2-98FE-00C0F0318AFE} - C:\WINDOWS\System32\Shdocvw.dll
O9 - Extra button: MoneySide - {E023F504-0C5A-4750-A1E7-A9046DEA8A21} - C:\Program Files\Microsoft Money\System\mnyviewer.dll
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O16 - DPF: {37A273C2-5129-11D5-BF37-00A0CCE8754B} (TTestGenXInstallObject) - http://www.mathxl.com/wizmodules/testge ... nstall.cab
O16 - DPF: {4ED9DDF0-7479-4BBE-9335-5A1EDB1D8A21} (McAfee.com Operating System Class) - http://download.mcafee.com/molbin/share ... insctl.cab
O16 - DPF: {4FE89055-5300-469E-AFAD-DEB3181EDE76} (PearsonAsstX Control) - http://www.mathxl.com/applets/PearsonInstallAsst.cab
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://update.microsoft.com/windowsupda ... 3036623678
O16 - DPF: {6E32070A-766D-4EE6-879C-DC1FA91D2FC3} (MUWebControl Class) - http://update.microsoft.com/microsoftup ... 3384494187
O16 - DPF: {8EB3FF4E-86A1-4717-884D-7BA2D38272CB} (F-Secure Online Scanner) - http://support.f-secure.com/ols/fscax.cab
O16 - DPF: {9A9307A0-7DA4-4DAF-B042-5009F29E09E1} (ActiveScan Installer Class) - http://acs.pandasoftware.com/activescan ... asinst.cab
O16 - DPF: {C4DD6732-1E82-4AE7-BD94-180331B84082} (DeltaCVX Control) - http://www.mathxl.com/applets/DeltaCVX.cab
O18 - Protocol: g7ps - {9EACF0FB-4FC7-436E-989B-3197142AD979} - C:\Program Files\Common Files\G7PS\Shared Files\G7PSDLL\G7PS.dll
O20 - Winlogon Notify: igfxcui - C:\WINDOWS\SYSTEM32\igfxsrvc.dll
O23 - Service: AutoComplete Service (Autocomplete) - Acesoft - C:\Program Files\Acesoft\Tracks Eraser Pro\delautocomp.exe
O23 - Service: CAISafe - Computer Associates International, Inc. - C:\Program Files\Yahoo!\Antivirus\ISafe.exe
O23 - Service: dlbx_device - Dell - C:\WINDOWS\System32\dlbxcoms.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Common Files\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: Kerio Personal Firewall 4 (KPF4) - Kerio Technologies - C:\Program Files\Kerio\Personal Firewall 4\kpf4ss.exe
O23 - Service: VET Message Service (VETMSGNT) - Computer Associates International, Inc. - C:\Program Files\Yahoo!\Antivirus\VetMsg.exe
O23 - Service: YPCService - Yahoo! Inc. - C:\WINDOWS\SYSTEM32\YPCSER~1.EXE
tanyasm
Regular Member
Posts: 52
Joined: November 24th, 2005, 12:37 am
Register to Remove
Hello and Welcome to Malware Removal,
Let’s do an ewido scan to check for malware.
Also are you familiar with this file tracker.exe? Is it part of My Deluxe Invoices program?
C:\Program Files\MySoftware\MyInvoices\tracker.exe
STEP 1.
======
Ewido Trojan Scanner
1. When installing, under "Additional Options" uncheck "Install background guard" and "Install scan via context menu".
2. When you run ewido for the first time, you may get a warning "Database could not be found!". Click OK. We will fix this in a moment.
3. From the main ewido screen, click on update in the left menu, then click the Start update button.
4. After the update finishes (the status bar at the bottom will display "Update successful")
5. Click on the Scanner button in the left menu, then click on Complete System Scan. This scan can take quite a while to run.
6. If ewido finds anything, it will pop up a notification. Select "clean" and check the boxes "Perform action with all infections" and "Create encrypted backup" before clicking on OK.
7. When the scan finishes, click on "Save Report". This will create a text file. Make sure you know where to find this file again.
Susan528
MRU Master
Posts: 1594
Joined: April 4th, 2005, 9:20 am
Location: Alabama, USA
edited on request by spotcheckbill - by ChrisRLG
Duplicated post.
SpotCheckBilly
MRU Master
Posts: 943
Joined: February 22nd, 2005, 5:14 am
Location: Twin Cities, MN
Hello tanyasm,
If you should still decide to run ewido, please post the ewido report and a new hijackthis log.
Susan528
MRU Master
Posts: 1594
Joined: April 4th, 2005, 9:20 am
Location: Alabama, USA
HJT Log
The reason why I think (thought) that the files were a virus or trojan is because when an employer attached a application and directions to an interview, the employer said that she only sent two attachments with the email, there were five attachments in the email. Also, before I spoke with her I save one of the attachments in my documents folder. Before I saved the file (oledata.mso) I wrote the name down so I can remember the name. When I went back to see the file I saved, It was not in the folder I saved it in. That was enough for me to think it was a virus or trojan. Also I have the following protection now installed on my computer thanks to your website:
Kerio personal firewall
Windows defender
eTrust EZ Antivirus (recommended from microsoft)
Should I still use the software that you recommend if so, should I uninstall my current protections.
Thank you,
Tanya
tanyasm
Regular Member
Posts: 52
Joined: November 24th, 2005, 12:37 am
I forgot to mention
I forget to mention that when I tried to use AVG and kerio firewall together I received a message that said the two programs conflicted with each other. So, I took AVG off. Can you please give me recommendations to all the firewalls and antivirus programs that works together. I know that you gave a list of things that are must haves but I know that I cannot install all of them together because they will conflict with each other. Which ones can I use together?
Thanks again,
Tanya
tanyasm
Regular Member
Posts: 52
Joined: November 24th, 2005, 12:37 am
Hello Tanya,
First off, sorry about the confusion with Susan528 and I both posting to your question. She has asked me to go ahead and continue working with you.
OK, let's see if I can answer your questions. The firewall, antivirus software, and anti-malware software that you are running are all good and highly regarded products. They should serve you well.
Now, on to the other software that I recommended. You probably don't need SpywareGuard as long as you are using Windows Defender.
The following programs do not use any system resources and they will not conflict with any other program, so you can add them with confidence:
Spywareblaster
MVPS Hosts file
Once they are installed, check frequently for updates.
You can find links for Spybot S&D
, in my signature below. Scanning with each of these programs on a regular basis (I do it twice weekly) will help to maintain a malware free computer. Since neither of these programs launch on start up (you launch and scan manually), they will not conflict with each other or any of the other recommended programs.
***Very Important***
Before you run either of these programs, please update and configure according to the Ad-Aware SE Personal Tutorial and Spybot S&D Tutorial.
Run each of them with a reboot in between.
I know that this sounds like an awful lot of work. But every one of these programs is simple to set up an easy to maintain. The most important thing of all to remember is UPDATE, UPDATE, UPDATE. Keeping everything, including Windows XP updated, is really your first line of defense against all the garbage that is out there.
SpotCheckBilly
SpotCheckBilly
MRU Master
Posts: 943
Joined: February 22nd, 2005, 5:14 am
Location: Twin Cities, MN
Glad we could be of assistance.
You can help support this site from this link :
Donations For Malware Removal
Do not bother contacting us if you are not the topic starter. A valid, working link to the closed topic is required along with the user name used. If the user name does not match the one in the thread linked, the email will be deleted.
NonSuch
Posts: 27301
Joined: February 23rd, 2005, 7:08 am
Location: California
Register to Remove
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Last post | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9225536584854126, "perplexity": 29896.53526641059}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-50/segments/1480698542213.61/warc/CC-MAIN-20161202170902-00059-ip-10-31-129-80.ec2.internal.warc.gz"} |
https://codevarsity.org/css3-transitions-css/ | CSS3 Transitions -CSS
CSS3 Transitions
Using CSS3 Transitions can be useful if you want your app or your web page to be more dynamic and good looking.
Indeed, transitions allow you to change property (`width`, `color`, …) values in a smooth way.
The `transition` property is a shorthand property for `transition-property`, `transition-duration`, `transition-timing-function`, `transition-delay`, the syntax is the following :
``transition: transition-property transition-duration transition-timing-function transition-delay``
For example :
``transition: width 2s ease-in-out 1s;``
Description of the properties
`transition-property`
Specify the name of property to which you should apply a transition :
• `background-color`
• `color`
• `width`
• `height`
• `margin`
• `border-radius`
• And so on !
For example :
``transition-property: width; /* means the transition applies on the width */``
`transition-duration`
Specify the number of seconds or milliseconds the transition should take :
For example :
``transition-duration: 2s /* means the transition effect last 2s */``
`transition-timing-function`
Specify the speed curve of the transition effect. Thus, you can change your transition’s speed over its duration.
Here are the most used values :
• `linear`
• `ease`
• `ease-in`
• `ease-out`
• `ease-in-out`
• `cubic-bezier(n, n, n, n)`
For example :
``transition-timing-function: linear``
N.B : All the values above are in fact specifics `cubic-bezier`. `linear`, for instance, is equivalent to `cubic-bezier(0.25,0.1,0.25,1)`
`transition-delay`
Specify in seconds or milliseconds when the transition will start.
For example :
``transition-delay: 1s /* means wait 1s before the transition effect start */``
How to use transitions ?
You can write a transition in two ways :
Using the shorthand property (`transition`)
``````div {
width: 200px;
transition: all 1s ease-in-out;
}
div:hover {
width: 300px;
}``````
Giving all transition properties a value
``````div {
width: 200px;
transition-property: width;
transition-duration: 1s;
transition-timing-function: ease-in-out;
}``````
N.B : Both examples are equivalent
Examples
Here are some simple pens containing simple transitions : | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9183497428894043, "perplexity": 7924.608144072143}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178369553.75/warc/CC-MAIN-20210304235759-20210305025759-00228.warc.gz"} |
http://koreascience.or.kr/article/JAKO200123443159729.page | # Effect of Glucose and Formic Acid on the Quality of Napiergrass Silage After Treatment With Urea
• Yunus, M. ;
• Ohba, N. ;
• Tobisa, M. ;
• Shimojo, M. ;
• Masuda, Y.
• Accepted : 2000.10.27
• Published : 2001.02.01
• 29 5
#### Abstract
Urea as a silage additive increases crude protein but reduces fermentation quality of silage by increasing pH and enhancing clostridial bacteria growth, especially in low sugar forages. Glucose and formic acid might be expected to compensate these defects caused by urea addition to grass silage. Thus, in this experiment urea formic acid or urea with glucose was applied to improve N content and the quality of napiergrass (Pennisetum purpureum Schumach.) silage. The first growth of napiergrass was harvested at 85 days of age and about 700 g of the grass was ensiled in laboratory silos (1.0 liter polyethylene containers) for 2, 7, 14, and 30 days at room temperature ($28^{\circ}C$). The treatments were no additives (control), urea, urea+glucose or urea+formic acid. Urea was added before ensiling at 0.5% of fresh weight of napiergrass and glucose and formic acid were added at 1% of fresh weight, respectively. After opening the silo, pH, dry matter content (DM), contents on DM basis of total N (TN), volatile basic nitrogen (VBN), lactic acid (LA), acetic acid (AA) and butyric acid (BA) were determined. The control at 30 days of fermentation showed 5.89 for pH with 13.8% for VBN/TN and 1.51% for AA. The addition of urea increased TN by about 1.5% units but decreased the fermentation quality by increasing pH from 5.89 to 6.86, increasing VBN/TN from 13.8% to 24.63%, increasing BA from 0.02% to 0.56%, and decreasing LA from 1.03% to 0.02%. Glucose addition with urea significantly decreased VBN/TN from 13.8% to 4.44% by reducing pH from 6.86 to 4.83 because of higher production of LA (2.62%). Adding urea and formic acid resulted in a more pronounced depression of VBN/TN and fermentation than the addition of urea and glucose. This study suggested that the combination of 1% glucose or 1% formic acid with 0.5% urea will improve nutritive value and fermentation quality of napiergrass silage.
#### Keywords
Napiergrass;Silage Quality;Urea;Glucose;Formic Acid
#### Cited by
1. Fermentation Quality of Round-Bale Silage as Affected by Additives and Ensiling Seasons in Dwarf Napiergrass (Pennisetum purpureum Schumach) vol.6, pp.4, 2016, https://doi.org/10.3390/agronomy6040048 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6099981069564819, "perplexity": 25972.97615988076}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496667767.6/warc/CC-MAIN-20191114002636-20191114030636-00373.warc.gz"} |
http://www.fractalnomics.com/2012/01/fractal-speed.html | ## Friday, January 6, 2012
### Fractal Speed
What is the maximum speed a fractal can be produced?
The fractal is produced at the fractal processing speed (fractal speed), this is the speed at which a discernible fractal shape can be created. This speed also determines the speed of zoom – or magnification into the fractal. It is also the speed of the fractal – wave.
Fractal zoom
Fractal speed can be demonstrated by drawing the Koch snowflake freehand. This is rather slow and timely; a much faster method is with modern computer as shown below. The speed is thus limited by the processing power of production. I have published in early entries on the production of the fractal. The average modern computer (in 2011) cannot produce many more than 7 iterations – in one view or 'fractal paradigm' – before the computer crashes. To produce more, or see more, we must zoom – forward and into and fractal.
The maximum zoom fractal speed must be 'Maxwell’s' – speed of light.
Fractal development
If this is so, then special relativity should also be consistent with the fractal as the fractal demonstrates increasing cost with the more iterations or production. The extra – marginal – cost, is mass in relativity. See diagram below: mass or cost limits the production speed.
It maybe that at the maximum fractal speed – the speed of light? – the fractal is also at a 'perfect' state of superposition where there is no reference points – and thus no connection to time. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9924721121788025, "perplexity": 1615.6938469232543}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610703518240.40/warc/CC-MAIN-20210119103923-20210119133923-00050.warc.gz"} |
https://www.ncbi.nlm.nih.gov/pubmed/22427191?dopt=Abstract | Format
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J Am Soc Mass Spectrom. 2012 Jun;23(6):1077-84. doi: 10.1007/s13361-012-0365-3. Epub 2012 Mar 17.
# Reactions of microsolvated organic compounds at ambient surfaces: droplet velocity, charge state, and solvent effects.
### Author information
1
Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA.
### Abstract
The exposure of charged microdroplets containing organic ions to solid-phase reagents at ambient surfaces results in heterogeneous ion/surface reactions. The electrosprayed droplets were driven pneumatically in ambient air and then electrically directed onto a surface coated with reagent. Using this reactive soft landing approach, acid-catalyzed Girard condensation was achieved at an ambient surface by directing droplets containing Girard T ions onto a dry keto-steroid. The charged droplet/surface reaction was much more efficient than the corresponding bulk solution-phase reaction performed on the same scale. The increase in product yield is ascribed to solvent evaporation, which causes moderate pH values in the starting droplet to reach extreme values and increases reagent concentrations. Comparisons are made with an experiment in which the droplets were pneumatically accelerated onto the ambient surface (reactive desorption electrospray ionization, DESI). The same reaction products were observed but differences in spatial distribution were seen associated with the "splash" of the high velocity DESI droplets. In a third type of experiment, the reactions of charged droplets with vapor phase reagents were examined by allowing electrosprayed droplets containing a reagent to intercept the headspace vapor of an analyte. Deposition onto a collector surface and mass analysis showed that samples in the vapor phase were captured by the electrospray droplets, and that instantaneous derivatization of the captured sample is possible in the open air. The systems examined under this condition included the derivatization of cortisone vapor with Girard T and that of 4-phenylpyridine N-oxide and 2-phenylacetophenone vapors with ethanolamine.
PMID:
22427191
DOI:
10.1007/s13361-012-0365-3
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f(t) = 3^(2t)/t To take the derivative of this function, use the quotient rule (u/v)'= (v*u' - u*v')/v^2. Applying that, f'(t) will be: f'(t) = (t * (3^(2t))' - 3^(2t)*(t)')/t^2 f'(t) =...
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https://beyondhighbrow.com/category/celebrities/ | ## Jimi Hendrix, “Purple Haze”
Jimi Hendrix Experience, “Purple Haze,” off their debut album, Are You Experienced? Look at him. He’s dressed like a hippie! Look at the album cover below? They’re all full-blown hippies. It was released in May 1967, only a month before the famous Summer of Love centered around the Haight-Ashbury district in San Francisco. This was peak hippie right around this time.
I’m not quite sure what the lyrics are about, but Purple Haze was definitely a very strong brand of LSD that was going around at the time. You want to know what “acid rock” was that all the parents back then were ranting about? Here you go. Acid rock, baby!
I believe Jimi Hendrix was a serious acidhead as were the other guys in his band. I knew a man who used to hang out with Hendrix and his entourage in the Seattle area where he came from. It was a group of about 200-300 people, mixed men and women, all full-blown hippies. Most of them were doing quite a bit of LSD too.
Black hippies were a thing back then, and Hendrix was absolutely a Black hippie. I’m sorry we hardly have any Black hippies around anymore. Either through self-selection or the general culture, Black hippies didn’t behave much worse than any other male hippies. This was the era of “Peace, Love, dope,” remember? Hippies freaked out if you even looked like you were getting angry. They tried to live their whole lives as free from “bad vibes” which included all forms of aggression and violence as possible. All of that was considered very “uncool.”
There were also some “Black hippie chicks” as we used to call them. Same thing, they acted pretty good too for whatever reason. The men and women both wore their hair in Afros. No Black women straightened their hair back then. An Afro was perfectly acceptable. The Black hippies lived hippie lifestyles, all the way down to the soft drug (pot and psychedelic) drug use.
I still have fond memories of Black hippies. This was a period when a group of both Blacks and Whites lived the same lifestyle without much bad behavior or racism. Racism was very frowned upon – keep in mind that all fellow hippies were your “brothers.” I don’t really like Black people having a separate culture. They’re not assimilating as long as they are doing that. And I would date a woman who was heavy into Black culture. All her friends and acquaintances will be Black and everywhere you go with her, it’ll be nothing but Black people and you’re the only White person around. Also I think assimilated Blacks act a lot better than the less assimilated, sort of like Jews in that regard.
I have no idea why Black people wish to have their own separate culture. I don’t get it. Isn’t ours good enough for y’all?
Lyrics:
Purple haze all in my brain
Lately things don’t seem the same
Actin’ funny, but I don’t know why
‘Scuse me while I kiss the sky
Purple haze all around
Don’t know if I’m comin’ up or down
Am I happy or in misery?
Whatever it is, that girl put a spell on me
Help me
Help me
Oh, no, no
Hammerin’
Talkin’ ’bout heart ‘n’ s-soul
I’m talkin’ about hard stuff
If everybody’s still around, fluff and ease, if
So far out my mind
Something’s happening, something’s happening
Ooo, ahhh
Ooo, ahhh
Ooo, ahhh
Ooo, ahhh, yeah!
Purple haze all in my eyes, uhh
Don’t know if it’s day or night
You got me blowin’, blowin’ my mind
Is it tomorrow or just the end of time?
Ooh
Help me
Ahh, yea-yeah, purple haze, yeah
Oh, no, oh
Oh, help me
Tell me, baby, tell me
I can’t go on like this
You’re makin’ me blow my mind, mama
N-no, nooo
No, it’s painful, baby
## The “Tom Hanks Is a Pedophile” Charges
I watched a video of some Qanon conspiracy theorist going on about the “Tom Hanks is a pedophile” story. He wouldn’t be a pedophile even if it was true because he seems like regular women just fine. Also the girl was 13 if what she says is even true. That’s too old for pedophiles. That’s called statutory rape, although, yes, in some states like California, it’s called child molestation.
That’s a bad law though because 13 year old girls are almost all pubertal. Menarche in the US now hits at age 13, and the physical sex drive comes on about four months before menarche. Prior to that I do not believe that girls have any physical or psychological sex drive at all. Kids simply don’t have a sex drive like we adults do. I don’t think boys have a sex drive either. I sure didn’t. I think I thought about sex maybe five minutes a year as a boy.
Anyway, there’s a woman out there who says that her father sold her to Tom Hanks at age 13 as a sex slave for Mr. Hanks. Well that’s one thing. Not only that but a mind-controlled sex slave, which is a concept I find dubious. I have no idea if she’s telling the truth. You’ve got me.
The video tries to make the case that Hanks puts international pedophilic codes into his tweets. I have no idea if that is true or not either. He tweeted a photo of a lost glove next to SRC USA. You put that into the Russian search engine Yandex, and you get a bunch of (apparently legal) pedophile sites. The man in the video proceeds to report all the sites to the hotline, but all of those sites were legal because every pic I saw on there was 100% legal.
## Alt Left: What Crime Did Prince Andrew Commit?
In the Epstein/Maxwell affair, the accusation from Virginia Giuffre (VG) is that she was ordered by Epstein to have sex with Prince Andrew a couple of times in order to gain blackmail material on him.
The faggots and cucks on Reddit are all screaming that Andrew committed “child rape.” “He raped a child!” they scream. What a bunch of homos. A recent post on Reddit ordered everyone to stop calling the “victims” of the “abuse” young women. “They were little girls!” the gays all screamed. Really? A 17 year old girl is a “little girl?” Have any of these dickwads ever met, spoken to, and spent time with an actual 17 year old girl? I have. They’re virtually adults. Hell, a lot of 16 year old girls and even a few 15 year old girls are practically adults for all intents and purposes.
Especially past 17 1/2, there’s not a whole lot of difference between them and an 18 year old adults. They’re inexperienced, they don’t know what they are doing, they’re awkward and clumsy when it comes to flirting and sex, but they’re very enthusiastic. Getting down to brass tacks, they are often quite immature, but I would call them more “very immature women” than girls. It’s far more of a woman than a girl, that’s for sure.
Next we look at the rape allegation. Supposedly Prince Andrew “raped” this girl! These Reddit “men” actually believe this feminist shit where half of all normal sex is rape. Good God, they’re queers.
She never tells us how the sex started with Epstein and Maxwell. Was she raped? Was she talked into it? There are allegations of “sex trafficking.” Sex trafficking means you are being held prisoner, you can’t really leave, or they are making it hard for you to leave by coercing you into staying somehow and threatening you with consequences, often violence, if you try to leave. Sex trafficking is sex slavery. You’re being held prisoner. It’s very much tied in with pimping, and Epstein was mostly a pimp before he was anything else. Maxwell was a madam, in effect a female pimp.
Was VG really a sex slave? How? That means she was being held prisoner? She was? How was she a prisoner? Giuffre was coerced into staying? How? Giuffre was threatened if she tried to leave? How?
I’ve been over this story for a long time. Giuffre never states that she was raped one time. She just says Epstein told me to have sex with this guy, so I did it. That’s perfectly legal because she was legal when he was doing that. Apparently this girl likes to follow orders. She’s a grown woman now, right? She still likes to follow orders? Tell her to come over and I will give her some sexual orders to obey, ok?
It’s not enough to say “I was Epstein’s sex slave.” She was legal. How exactly did Epstein make her his sex slave? He said, “You are my sex slave. You shalt obey me, miss.” And this fool girl believed that? Well, that’s legal.
Prince Andrew had sex with this girl in Virgin Islands. She was legal, 17. AOC is 16 in Virgin Islands. Someone explain to me how it is rape and sexual abuse to have consensual sex with a perfectly legal girl. I’m dying to know. VG was legal everywhere she had sex with Andrew. She was legal in New York. She was legal in New Mexico. She was legal in the UK. Please explain how consensual sex with a perfectly legal girl is rape in any of these places.
VG was a “sex slave” from 17-23, apparently, so most of this was when she was a grown woman. Why all the focus on the one year when she was a girl, albeit a legal one? Between ages of 18-25, was she being “raped” or “abused” the whole time? Most gay media stories on this subject say she was “abused” from ages of 18-23. How in God’s name can a grown woman be “sexually abused?” She can’t. Even teenage girls can’t be “sexually abused.””
Sexual abuse only refers to child molestation, generally but not always sex with a child under 13. The media also says that VG was “abused” when she was 17. Every time she went off to have sex with some guy Epstein told her to, she got “abused.” How in the Hell did she get “abused” by having consensual sex with all of these men? Keep in mind she was completely legal.
I’m not feeling a lot for this silly woman. She got paid $15,000 for getting “raped” and “abused” by Andrew, and apparently she got paid big money every time she had sex with someone Epstein told her too. Sounds like she’s making pretty good money for a girl working on her back. I never knew getting “raped” and “abused” paid so well. Hell, at rates like that, I might even let myself get “raped” and “abused.” But really, I’m feeling terribly sorry for this woman. I’m sure that must have been horribly traumatic to get all that money for one consensual sex act! If some hot chick gave me$15K for sleeping with her, I’d be traumatized for years! I’d have PTSD for the rest of my life!
People are saying that Andrew may have bought this girl. No one knows if Andrew bought her. Epstein was probably just giving this girl away to his friends. I doubt he was charging anyone. This seems to be about the worst they have on Andrew. If he bought her, Andrew is guilty of the crime of – gasp – buying a prostitute. Like this doesn’t happen millions of times every day in the US. Like rich men don’t buy prostitutes all over the world all the time.
On the other hand, she was a minor. It was legal to have sex with her but not to pay her for it. So if he knew she was underage, he’s guilty of the crime of buying an underage prostitute, which apparently some sort of a crime, even if it’s not called that. We now know that he knew she was 17.
Fine, but did he pay her or not? That’s the important part here. Even if he did, frankly, men who buy underage prostitutes are almost never convicted. You have to prove they knew she was underage, and that’s hard to do. Generally they go after the pimps who are pimping these girls out, not the customers. Men probably buy underage prostitutes tens of thousands of times a day in this country.
They are also saying that he committed some crime called “Buying a Trafficked Prostitute.” But that’s only if he bought her. There’s no such crime as “Having Sex with a Trafficked Prostitute.” You can have all the sex you want with these trafficked women. You just can’t pay them for it.
Neither of these are even crimes. Show me where there are crimes called that. As I said, cops don’t worry about the buyers. They have a hard enough time keeping up with the pimps and the traffickers.
Ok, VG’s a prostitute. She’s a whore. Nothing but a little teenie whore, and a well-paid one at that. Epstein is pimping out an underage prostitute, and he may also be trafficking her. And pimping out an underage prostitute is indeed a crime. I forget what it is called, maybe something like “Profiting from Underage Prostitution.” I recently looked over the sex laws in some European countries and a number of them had crimes along those lines, phrased in different ways.
The problem with the trafficking laws is the way they were written. As noted above, the trafficking laws are designed to prevent human slavery of various kinds. The sex trafficking laws are designed to fight what is better known as sex slavery. These women are imprisoned. They can’t leave. They’re being forced to prostitute themselves or forced to work for some particular pimp.
But the law was abused by the pigs at the same time it was written. It applied to not only the sex slavery, as was proper, but it threw in the notion that anyone pimping underage prostitutes was automatically engaging in sex slavery. So the law is designed to prevent trafficking in prostituted sex slaves and also underage prostitutes.
The problem is that the addition of “and also if they are underage” part to the law is that this goes against the spirit of the law – that it was designed to prevent sex slavery. There’s no proof that all underage prostitutes being pimped out are sex slaves, though tragically quite a few probably are exactly that. It’s just more pigs abusing laws and writing laws based on emotional hysteria rather than clear-eyed, cold, legal logic.
But anyway, Andrew just had sex with some legal girl, probably for free. He may have had no idea she was a prostitute or not, and if he didn’t pay her, it doesn’t matter. He knew her age but she was legal. He probably had no idea she was being “trafficked,” and it wouldn’t matter if he did unless he bought her and even then, nobody gets prosecuted for such a crime.
Precisely what crime did Andrew commit here?
Inquiring minds wish to know.
## The Ronettes, “Be My Baby”
The night we met, I knew I needed you so
And if I had the chance, I’d never let you go
So won’t you say you love me
I’ll make you so proud of me
We’ll make ’em turn their heads every place we go
So won’t you please be my, be my baby
Be my little baby, my one and only baby
Say you’ll be my darlin’, be my, be my baby
Be my baby now, my one and only baby
Wha oh oh oh
I’ll make you happy baby, just wait and see
For every kiss you give me, I’ll give you three
Oh since the day I saw you
I have been waiting for you
You know I will adore you ’til eternity
So won’t you please be my, be my baby
Be my little baby, my one and only baby
Say you’ll be my darlin’, be my, be my baby
Be my baby now, my one and only baby
Wha oh oh oh oh
So come on and please be my, be my baby
Be my little baby, my one and only baby
Say you’ll be my darlin’, be my, be my baby
Be my baby now, my one and only baby
Wha oh oh oh
Be my, be my baby, be my little baby
My one and only baby, oh oh
Be my, be my baby, oh
My one and only baby, wha oh oh oh oh
Be my, be my baby, oh
My one and only baby, oh
Be my, be my baby, oh
Be my baby now
From 1963! Sometimes I think this song is better than either of the previous two. I had no idea they were making such great music in 1963 for Chrissake.
From the complete psycho but legendary genius Phil Spector. He was always nuts. He was even nuts back in the 60’s. People hated working for him because he was so crazy and unstable. And he’d been into guns for a long time before his bizarre murder conviction in 2009.
He treated Ronnie Spector like complete crap and almost ruined her life. He did weird sexual things with his sons like forcing them to simulate sex acts on his girlfriend. They’re probably screwed up by this idiot too.
In 2009 he shot a woman dead in his mansion for no apparent reason. But he’d had a habit of pulling guns on women for some time. I hate to say it, but I really think that men like Phil Spector hate women. If you love women, why would you pull guns on them all the time?
How many times have I told you that artists are crazy? And the real geniuses are often the craziest of them all.
## Michael Jackson – Part of a New Race of Humans?
Polar Bear: MJ eventually became raceless. Many people of every race and gender start to look like him after too much plastic surgery. Should’ve kept his natural black face IMO. Not sure how he triumphed over White men. I can maybe how he did it with White boys, though at least one accuser lied. He was more into being “human” than Black or White in any case.
I actually felt this way myself and I believe I even remarked on it. And this was way back in the day before I was, um, racially aware, race-wise, or race realist. I think I said:
Michael Jackson isn’t part of any race anymore. He’s not really Black and he’s not really White.
And the people I said it to all nodded their heads and laughed. This was before this latest ultra-radical brand of PC/SJW BS and you could say stuff like that without people freaking out and calling you racist or trying to shut down the conversation.
I think instead of forming his own race though as the title said, MJ simply became as Polar Bear implies, “raceless.” That’s kind of a neat word, “raceless.” I rather like it. But the SJW’s will insist that people always have a race, except for White people since our race doesn’t exist while everyone else’s does ha ha.
## Kobe Bryant’s Death on Stormfront
Haven’t read the articles yet. Should be amusing – LOL. I think celebrity deaths are over-hyped, but then again, it depends on what you’re into.
Of course there will probably be articles on WN sites about the Jew-hyped superstar that Whites were supposed to worship.
###### What Was More Tragic?
His death or the death of his non-celebrity daughter at only 13?
## Dick Dale, “Miserlou”
Speak of the Devil. What do you know, Miserlou itself, rising from the ashen surf. This version the famous one from 1962 by Dick Dale and the Deltones.
He didn’t really write this song. it’s actually called “Misirlou”. It’s origins are in the late days of the Ottoman Empire, possibly with Greeks and Armenians living in Anatolia and Arabs living nearby in the northern Levant and Mesopotamia. I believe the origin is probably with Greek musicians, possibly Pontic Greeks living in Anatolia. Hence, this joyous song sprung right up from the blood-drenched soil of genocide. Perhaps the song represents a rebirth?
The earliest known version is by a Greek band from 1927. In the early 20’s, it was played by Greek, Arab, and Jewish musicians. There are also Turkish, Iranian, and Indian versions of the song. It does sound like belly dancer music if you listen to it, no?
From the “Pulp Fiction” soundtrack, which was of course one of the greatest movies of the past half-century or so. This is probably Tarantino’s swan song. The bisexual man John Travolta was incredible in this movie. I really didn’t know he had it in him. I thought he would play his Saturday Night Fever character the rest of his life. Another great movie by the way. From the late 1970’s, the ultimate disco movie.
Samuel Jackson was incredible too. One of the finest Black actors up there. I swear he’s as good as De Niro and Hoffman.
## The Pete Townsend Child Porn Case and the Phenomenon of Adults Molested as Children Seeking out Child Porn to Watch
Greg Rambo: Since you’re on the subject of CP/pedos, whatever happened with the legal case against Pete Townsend of The Who for accessing child porno? The only reason I ask is because I understand he and Roger Daltrey are about to go out on another Who tour, but I don’t know if they have any U.S. dates planned.
The last time they tried to come here a few years ago and do a Super Bowl halftime gig, there were all kinds of protests to keep Townsend out of this country. Not that people are lined up to see a couple of 74, 75 year old guys get up on stage, but I thought the concert promoters would shun him due to his charges in England of accessing child porno online.
I’m not sure but I think Pete Townsend was pretty much innocent. I believe got molested himself as a kid and that’s why he was looking this stuff up.
Actually a fair number of people looking at CP on the web are females who were molested as girls, and due to that being done to them, go looking for CP of other girls getting that done to them. These women have no interest in molesting children. I have no idea what they are doing. Perhaps they are reliving their trauma in some way or another and perhaps Townsend was doing the same thing. I am certain that Pete Townsend is not a pedophile.
I remember there was a very famous CP case, probably the most famous series of CP videos ever made, of a girl’s father who made CP of him having sex with the daughter when she was quite young (9-13?).
Of course I haven’t seen any of these videos, but I have seen a minute or two of the clean part of one of them where she is sitting in a chair with all her clothes on fidgeting, and then introduces herself. She’s 9 years old and even though there’s no CP in the clip I saw, it still freaked the living Hell out of me because she’s such a young girl.
There’s nothing wrong with watching nonsexual parts of CP clips. You can go to the FBI site and watch clips of CP videos where nothing sexual is happening. They want to see if you recognize the girl or the man or man’s voice in the video. It’s still creepy though because the girls are so young that it freaks you out. In one that I saw, you can only hear the guy’s voice, and that combined with such a young girl on the screen has a very creepy effect.
I believe they estimate that 4-5 million people have watched at least one of those famous videos. Do you see what I am talking about when I say that LE is swamped by this stuff? Suppose LE went on a goose chase to hunt down 4-5 million mostly men who watched those videos?
They don’t have the resources or time to hunt down even 10% or probably even 1% of those guys. The prison and jail population would double or triple. That’s what I mean when I say they have triage this stuff and only go after the worst.
If anyone remembers the girl’s name, tell me in the comments. Those videos were famous all over the world.
I’ve never seen the videos, but I have been told that the girl is clearly enjoying it, and it’s also clear that she deeply loves her father and vice versa. I told you the morality of this stuff is complicated, right? In fact there are quite a few people out there who think there is nothing wrong with these videos as they simply show a girl and her father showing their deep love for each other. I don’t think that’s a good argument.
However, child porn star became an adult and had a change of heart and decided that she got molested and that this was not ok at all. Anyway she became very angry about what was done to her considering that lots of copies of this video were floating around the Net.
Out of this large number, they selected out the 1,500 wealthiest and sued them for everything they had under “deep pockets” legal doctrine. And she won. I believe she got $1.5 million out of one man. I thought it was a bit ridiculous, but my Mom vociferously defended the lawsuit and had no sympathy for the guy. No one went to jail. It was a civil case. So one reason you might not want to download real CP onto your drive is that the girl might grow up to be a woman and she might sue you for everything you’ve got for saving the video she was in to your drive. Something to think about. There are discussions of these videos on the Net among people who have seen it. At one time I read a number of these discussions. Most of the people discussing the videos were young men, and few of them seemed to be actual pedos. Mostly they just seemed to be curiosity seekers or men driven by the lure of the forbidden. But I was surprised at how many women who had been molested as girls had watched these very famous CP videos. There were quite a women like this on the threads making thoughtful comments about the videos. I have no idea why women who got molested as girls go look at CP. Perhaps as with Townsend above, they are reliving their trauma and see this is as somehow therapeutic. So not everyone looking at CP is a bad person. A lot of them are, but not all of them. ## Alt Left: The Crimes of Jeffrey Epstein Will Shudder You to Your Very Bones Jeffrey Epstein was finally arrested again recently after he got off pretty much scot free from his previous charges, serving only 13 months in a minimum security prison where he was allowed to leave on work release for 12 hours a day. They refiled new charges on him for sex trafficking, as the previous charges were simply for buying a prostitute or pandering prostitution. The girl was only 14 but who cares about that? She was a little whore like most all of the rest of them. Epstein paid her good cash to jerk him off, and she was so traumatized that just like all the others, she kept coming back scores of times to jerk him off for$300 over and over again. In fact the traumatization was so horrific that she found herself recruiting other teenies to be teen whores just like her for the handjobs and a hand full of hundreds at the end.
I’m sure it must have been so horrible. They were free to leave at any time, but it was so horrific that they just had to come back countless times to be teen whores over and over again.
Oh, poor girls! I’m sure their lives are ruined. All those horrible handjobs for a very handsome and very rich man, and they only got a measly $300 each time! It’s so hard to be a girl! If you feel horny and you want to have sex, you have to get paid hundreds of dollars for it, while us boys get to pay all our own money for sex instead. It’s so much more fun to pay for sex instead of raking in the cash to get laid like a little teenie whore! This is really all about metoo. When those teen whores besieged his door for the$300 handjobs, Epstein should have been proper and turned the little teen sluts away. Instead he grotesquely harassed, abused, raped, and molested these poor eager willing girls, and to make things even worse and increase the shame and horror, he paid them hundreds of dollars to get laid or perform a harmless meager sex act they were already doing with all the boys their age anyway.
This is sick. When will men ever stop abusing girls and women by paying them to get laid! It’s got to stop. The abuse, the harassment, the endless consensual rapes, the hundreds of dollars all these sluts rake in to get laid and get their rocks off, it’s just so awful.
It makes me ashamed to be a man. To think we treat women this way! How horrible! How awful! No wonder women hate us!
All their money is for them, and all our money is for them, and to make matters worse, they get paid big money for the torturous horror of getting laid! Horrifying! While we men escape the whole horrorshow by giving women all of our money just for existing.
Just think of women were giving us men hundreds of dollars to get laid by hot women. We men would all be screaming metoo!
Metoo! Metoo! Metoo!
Come on, men. Scream it with me. Cry while you do! Cry for our sisters!
These poor women, they can get laid anytime they want, and they even get paid good money for getting fucked. Tragic! The lot of women is a sad one. Nothing but sadness and pain. It’s pain and sorrow all the way, and then they die!
I’m sad! I’m crying! I’m crying for all you girls and women out there! I know! I know! I feel your pain, ladies, I feel your pain. Come let me hold your female heads in my lap while I comfort you for your sorrowful lot in life! And I promise I won’t pay you \$300 to let me do it. I’m not that kind of a guy! I’m a good man!
## Jeffrey Epstein Dead Photos
Here is another photo of Jeffrey Epstein after he committed suicide.
Well you all know who is he now or you should. If you don’t know why he is famous or important, just Google his name to find out all about him. This guy is worth a number of posts simply in and of himself. For now I will settle for his death photos, as there are idiots insisting he’s not really dead. This is a fake dummy and Epstein is really alive in Israel sunning on a beach surrounded by gorgeous 18-23 year old women.
## “High Ridin’ Heroes,” by Tanya Tucker
Daylight or midnight
Red eyes and that old hat
Whiskey-bent and busted flat
She’s a credit to her flaws
She’s a bad risk, but a good friend
Small change and loose ends
She only regrets that she might’ve been
A little faster on the draw
Those old high ridin’ heroes
They’re anywhere the wind blows
She’s been to hell and Texas
And she knows how it feels
To be ridin’ that hot streak
And drunk on some back street
Falling off the wagon
And under the wheels
Time was when she was queen
Now the rodeo’s just this old girl’s dream
The highs are few and far between
The lows get the rest
These old hard times ain’t nothin’ new
Once you’ve done the best you can do
You just tip your hat to the wild and blue
And you ride off to the West
[Chorus]
Those old high ridin’ heroes
They’re anywhere the wind blows
She’s been to hell and Texas
And she knows how it feels
To be ridin’ that hot streak
And drunk on some back street
Falling off the wagon
And under the wheels
Those old high ridin’ heroes
They’re anywhere the wind blows
She’s been to hell and Texas
And she knows how it feels
To be ridin’ that hot streak
And drunk on some back street
Falling off the wagon
And under the wheels
Very, very nice.
This is some real country music. I mean the real thing. If you hate country music at all, there’s no way you will like this song.
The singer is Tanya Tucker. She’s a hardcore country artist. I never got into her music too much, but this song is out of this world. It actually sounds like the Flying Burrito Brothers! Even more than that, it sounds like Texan Country Rock. Think Doug Sahm. Or maybe, if you can imagine it, ZZ Top.
Although this album is very Texan and Tucker has a very country voice, she never lived in Texas. She was born in Arizona and her family then moved to Utah. Later they moved to Nevada. None of the people in those places have country accents last time I checked.
This song was written by country singer David Lynn Jones. It was actually written about a female rodeo rider that he knew, but Tucker reinterpreted it to weave it into her own life, quite nicely too.
Waylon Jennings guested on Jones’ album Hard Times on Easy Street. Waylon’s son, Shooter Jennings, via his wife Jessi Colter, is a Southern Rock singer-songwriter who has produced several excellent albums. He has also produced Marylin Manson and Guns n Roses bassist Duff McCagan. Shooter produced Tanya’s new album.
This song is off of Tucker’s latest album While I’m Livin’. Tucker is one of country music’s famous female outlaws, in part for her hard-partying ways. She inspired other female outlaw types like the Dixie Chicks.
Her first album was Delta Dawn in 1972, released when she was only a teenager. Although the cover by Helen Reddy is better known, Tucker’s version is fantastic. She has always had an awesome gritty southern voice, and her storytelling is legendary. Tucker did well through the 70’s and 80’s, and she is a 10-time Grammy winner. But the country scene started leaving her behind already when she adopted a much more country rock sound in 1978.
For the last few decades her star has faded quite a bit. People wonder who she is. Is she still alive or what?
Shockingly, this could well be the best music of her career. And she’s over 60 and has been singing for 40 years. This is odd as rock musicians tend to peak quite early, in the late teens to 20’s. They make great music for 10 years or so, typically burning out by 35-40 just when novelists hit their peak (Gravity’s Rainbow, Ulysses and Moby Dick were all written between ages 32-40).
In this sense, rock musicians are like classical music prodigies, who also peak young and mathematicians, who of course peak young. Perhaps music and math genius are down to fluid IQ, which is frankly a measure of pure brain speed. Fluid IQ peaks at age 23, which is just coincidentally when we have the maximum number of brain cells.
Not that IQ tests measure intelligence or anything like that. It’s mere coincidence that IQ peaks at the very same time we have the most brain cells!
So a singer-songwriter making her best album at age 60 after a 40 year career is a pretty amazing thing.
She lived quite the hard life when young. As a teenager, she was a chart-topper and award-winner who ended up going broke eight years later and moving back in with her parents. She had a wild one year affair with Glen Campbell of Rhinestone Cowboy fame, a tabloid year full of drinking, cocaine and crazy spats.
During the 80’s, Tanya had a blast. She drank like a fish and sniffed up half of Peru. She bragged that she would out-party any man. By 1988, it was all over and she was checking into the Betty Ford Clinic. That’s probably the only reason she’s still alive.
This song harkens back to the time around when she was checking into the Ford Clinic only two years after her chart-topping Girls Like Me album. She was at the top charts of music and at the bottom of the wells of addiction, both at the same time.
The highest of highs and the lowest of lows, dancing off together, gripped sickly tight in hate and love and life and death, across the stage of the fame as it all crashed down around her to the roars of adoring crowds as she fell down drunk in the aisles.
We’re waiting for you, on the edges of our chairs, ears tilted to the anxious sky.
Come on. Come on back home again.
Welcome back, Tanya.
## Happy 50th Birthday Give Peace a Chance
The official video from the song, no less. Recorded in Montreal, Canada in Room 1742 at the Queen Elizabeth Hotel in June 1969 with John and Yoko singing backed by the Plastic Ono Band. The song was released while John was still part of the Beatles.
The other Beatles hated that John was with Yoko. “That Okinawan witch,” Paul McCarthy referred to her. Yoko was a very avant-garde artist from Japan who speak English as a second language. The two were very much in love, though John used to beat her up in the 1970’s when they lived in New York.
One of the greatest antiwar songs of all time. From the anti-Vietnam War Movement of that time. I am wondering. Will we ever have another antiwar movement ever again in this blighted land? I think it will never happen again. Just one more way we have gone backwards in fifty years.
At 1:38, 2:05,3:38, and again at 4:50, guess who that is? None other than Timothy Leary himself! Every time I see Tim Leary, he’s always got an ear to ear smile across his face.
I saw him once in a video store on Sunset Boulevard, Hollywood in 1985. He was renting a copy of Amadeus at 10 PM. My friend said, “Bob! Look! It’s Timothy Leary! The Godhead! And he put his hands together and prayer and started bowing to the Prince of LSD. He was smiling then too, same thing. His teeth lit up the room, and you couldn’t frown if you tried. I guess if you took as much acid as he did, you might have a perma-smile on your face too, right?
Who’s that at 1:52? Allen Ginsberg? Gotta be him. It can’t be anyone else.
Who’s that at 2:48? It’s got to be Tommy Smothers!
And the gorgeous Rosemary Woodruff Leary from the start off and on until :46 and then again in several places. Got to be her. Plus she’s sitting right next to Tim.
Derek Taylor at 1:22. The famous record producer and journalist known as “The Fifth Beatle.”
Tommy Cooper, the comedian and magician, in the background at 1:07 and again at 3:06? Could well be.
Now we have to find Dylan and Mailer, and we’re home free.
They don’t mention her in the song, but can anyone spot the woman at 4:02. I can. It’s Petula Clark, the famous actress!
Bagism, Shagism, Dragism, Madism, Ragism, Tagism
This-ism, that-ism, is-m, is-m, is-m
All we are saying is give peace a chance
All we are saying is give peace a chance
C’mon
Ministers, sinisters, banisters and canisters
Bishops and fishops and rabbis and Popeyes
And bye bye, bye byes
All we are saying is give peace a chance
All we are saying is give peace a chance
Let me tell you now
Revolution, evolution, masturbation
Flagellation, regulation, integrations
Meditations, United Nations
Congratulations
All we are saying is give peace a chance
All we are saying is give peace a chance
John and Yoko, Timmy Leary, Rosemary Tommy Smothers, Bobby Dylan
Tommy Cooper, Derek Taylor
Norman Mailer, Alan Ginsberg
Hare Krishna
Hare, Hare Krishna
All we are saying is give peace a chance
All we are saying is give peace a chance
All we are saying is give peace a chance
All we are saying is give peace a chance
## Was George Michael Gay or Bisexual?
George said in some interviews that he had had sex at first with many women and some men and because of this he identified as bisexual. But around 27 he fell in love for the first time – with a man. And then it was clear for him that he was (mostly) gay.
He is free to identify that way, but he was strongly attracted to women’s bodies. He stated this numerous times. However, he did say that he realized he could only fall in love with a man. I find it hard to classify a man who is strongly attracted to women’s bodies as gay. That doesn’t really work for me. I’ve never met a single gay man who was attracted to women’s bodies at all, I mean even 1%, in a real sense. Furthermore, it’s very weird for a gay man to have sex with many women. That’s what players do. Gay men do have sex with women at times, but few if any of them are players.
## Who Is This Woman, and What in God's Name Happened to Her?
And what in God’s name happened to her? How do you go from the most beautiful woman on Earth to this? She looks like she’s been carpet bombed by a B-52 called “Time” for a while now.
The thing is, no matter how beautiful or handsome you are, there will come a day when you are old and ugly, assuming you are lucky enough to make it that far in the first place.
Time heals all wounds, but it also wounds all heels, and before it kills us, first it makes us ugly as sin, just to rub it in.
Golden years my ass!
When you bet on the body, you bet on a losing horse.
– Buddhist saying.
Well, she’s 83. Who looks good at 83? On the other hand, I have an aunt who is 82 and she is actually smoking hot! And I met a woman recently at a dinner at the clubhouse in my Mom’s retirement village and she looked good! My Mom said the woman was as old as my Mom, and my Mom’s 85. Even at 83, she should look better than that. Gloria Steinem is in her 80’s, and she’s hot!
## Who Is This Woman?
Who is this woman? What was her occupation? What was she famous for? If you can fathom that the woman on the left is the same as the one on the right, what in God’s name did the wages of time inflict on this poor soul. She looks like she swallowed a whale.
## Can You Be Androgynous yet Be Heterosexual/Straight?
The best definition of an androgynous man is a man who has strong masculine and strong feminine characteristics going at the same time. Remember glam rock back in the 1970’s? Many of those male rockers were quite androgynous, and most of them were very heterosexual or at least leaned straight.
Another definition of androgynous means a man who looks and acts so much like a woman that you can’t tell if he is a man or a woman. Or the opposite in a woman. Almost all if not all such cases of extremely feminine men who appear to be women and extremely masculine women who seem to be men that I have studied are in fact homosexuals. In fact they are very gay.
Now if you include men like Prince as androgynes, there are indeed some straight men like this, as Prince was completely heterosexual.
Honestly we straight men had a lot more leeway in terms of true androgyny back in the 70’s. A straight man could wear scarves, velvet pants, silk shirts, short kimonos, smoking jackets, tight jeans, dancing shoes, and four inch blue platform heels without most people suggesting you were gay. People would just say you were “styling it.” You can act a lot softer, gentler, or more androgynous. You could have a strong feminine side, especially if you matched it with a strong masculine side.
Back then, people were assumed straight until proven otherwise, and there were not many out gays anyways. Accusing a man of being gay was a very serious matter, as this was seen as a horrible insult if he was straight. So most men were simply assumed, correctly, to be straight until proven otherwise. If you wanted to accuse a man of being gay, you had better have had some pretty damn good evidence to back it up.
I am actually nostalgic for those days. I had so much more freedom back then in terms of both clothing and behavior.
Now that gays are so out, we straight men can no longer wear those wild clothes I talked about above nor can we act the way I did back then. If I tried to wear any of that stuff now that I wore back then, people would automatically assume that I was gay or bi. If I told them I was straight, no one would believe me, and they would all accuse me of lying. Compared to back then, acceptable behavior and garb for straight men has become dramatically restricted.
It’s not been a positive change. We have gone backwards in a huge way.
## What Percentage of Transsexuals are Heterosexual before Transitioning and Remain Oriented to the Same Sex after Transition?
Early onset transsexualism is usually an extreme form of homosexuality. 90% of early onset male to female transsexuals were gay men before they transitioned, so after transition, they remain attracted to men. Nearly all early onset female to male transsexuals were lesbians before they transitioned. After they transition, they remain attracted to women. Heterosexual early-onset transsexuals are rare, especially among women. In the older literature, early onset male to female transsexuals are referred to as Classic Transsexuals.
Late onset male to female transsexualism is probably related to autogynophilia and is almost certainly not organic. In the older literature, these people are called Fetishistic Transsexuals.
Autogynophilia is a paraphilia that is developmental as all paraphilias are. These men are turned on sexually by the image of themselves as a woman. Bruce/Caitlin Jenner is almost certainly this type of transsexual.
However, these men differ from traditional fetishistic transvestites in many ways, as they have cross-dressed more and for longer, and they are much more likely to see themselves as women.
Of late onset male to female or Fetishistic transsexuals, 1/3 are gay, 1/3 are bisexual, and 1/3 are straight. Oddly enough, many late onset male to female transsexuals have been extremely masculine in their lives before they became transsexual.
## Is Paul Stanley Gay or Bisexual?
Answered on Quora (Stanley is the lead singer of KISS):
Thank you! That’s an excellent question. I have studied this question for an article I wrote about gay and bisexual rock stars.
Paul Stanley is one of the most legendary womanizers in all of rock and roll. He has probably had sex with hundreds of women. No gay man does that, nor has any gay man ever done that. Any man who does that cannot possibly be gay, and he almost always leans straight. These men are frankly the most heterosexual men of us all.
Some people have said that he is effeminate, and he does have some effeminate behaviors. At least one groupie said his effeminacy creeped her out – she didn’t like it. I do not think Stanley is strongly effeminate, but he has a few behaviors like that, in particular the way he holds his hands when he sits.
Despite his reputation as a womanizer, he has long been rumored to be bisexual. Groupie boards report that he is bisexual. Ace Frehley and Ace’s wife have both stated that Stanley is bisexual. I think he is much less interested in men than he is in women. We can see this by his legendary womanizing. That is an indication of how he leans sexually. Paul Stanley is a predominantly straight man with some minor bisexual leanings in my opinion.
He is now married with children for some years.
## Cat Stevens, "Morning Has Broken"
Cat Stevens, Morning Has Broken, 1976.
That sure is great music, isn’t it? I used to love Cat Stevens, and I think I still do. I don’t see why you can’t love Cat Stevens and the Sex Pistols both at the same time. After all, there’s really only two kinds of music, good music and bad music. All the genres are pretty useless, especially when people get chauvinistic about them.
He later converted to Islam and became Yusuf Islam, moved to the UK, and idiotically got on the US government’s No Fly List. Is Cat Stevens a terrorist? Come on! He made some lousy statements about Salman Rushdie, suggesting that the ayatollahs were right to put out a death threat on him. Shows what happens when you convert to Islam. A decent man can convert to Islam and become a monster because even a normative interpretation of Islam (apostates must be killed) is brutal, extreme, and homicidal. I’m not saying that this is always what happens, but Islam is hardly a religion. The rule about dealing with apostates shows right there that this is no peaceful religion. No sir!
## R. Kelly, Scumbag
Wow.
This is bad. I knew this guy was bad, but I never knew he was this bad. I doubt if he is doing anything illegal here. It’s not illegal to be a controlling sociopathic POS. It’s not illegal to control your women’s movements, tell them what to do and when, ask for permission for anything, etc. It’s not illegal to run a cult.
I do not think any of these things should be illegal.
## Chris Cornell Is Dead
Chris Cornell, legendary guitarist from the band Soundgarden, etc. is dead. He died on May 17, three weeks ago, but I just heard about it today. Apparently out of the grunge scene in Seattle in the 1990’s. I do not know much about this band, having stopped following rock and roll sometime in the 1980’s, but apparently he and his band were huge in that scene. The Space Needle in Seattle went dark between 9 and 10 PM after his death. Death was suicide by hanging. Apparently he had been depressed and had suffered from depression and drug abuse in the past, although he was clean at the time other than some prescription benzos, which he did not take enough of to kill him. He was 52 years old.
Chris Cornell presente!
## Robert Stark interviews Tila Tequila
Look, Robert Stark is one of my best friends in the whole world, and I really do mean that, but this interview…I don’t know what to say…well, it’s the silliest one he has ever done. It’s not his fault actually because the person he interviewed here is a Certified Idiot. Yes, she is beautiful and a hottie and bla bla bla all that, but she is also an idiot. A real, true blue, dyed in the wool idiot.
I do not mean to insult her intelligence as some have done. She is 3/4 Vietnamese and 1/4 White from good stock on both sides, so that leaves one with at least a 100 IQ. I did not get the impression listening to this interview that she is unintelligent. Actually, for someone with a reputation for being a slut airhead, I thought she was rather smart comparatively. Viets are smart. They are about as smart as Whites (Viet IQ = 99, White IQ = 100), but they seem to achieve even more, which I do not understand. Perhaps this is down to extra-IQ factors that I discussed before.
Instead of being unintelligent, she is merely a fool. A nut. A kook. A whackjob. You get the picture. Go the SPLC site and read about all of her insane transformations down throughout the years – her most recent one being a Vietnamese Hitler-loving Nazi (no, I am serious). The one thing I get out of all of this nonsense is that she is some publicity loving celebrity who learned in Hollywood that all publicity is good publicity (not really true by the way) and is now trolling the world based on this noble concept.
Either that or she actually is nuts. Or she is just another crazy broad in the MRA sense that “all bitches are crazy.” Or…or…or…I think maybe this is all just a big troll, but she is too dumb to figure that out. Anyway, intentional or not, it’s a great troll. Good job Tia! You are tied with the Donald in the Trolling IRL category. Yay!
So I offer this interview. Nothing in this interview makes much sense, but then it is just some ditzy airhead broad anyway. She used to be a totally stoned-out Hollywood whore who even made porno flicks. Yep, she made a great lesbian porn flick with two very hot porn stars, and all you perverts (males) on here really need to go search for that and go watch it right this minute. That’s an order! Just make sure you are somewhere where you can whip it out while you watch it because you may have to. It’s hot! Tia is a hot lesbian porn star! Yay!
A typically perpetually confused modern woman, Tia has trendily changed her sexual orientation all over the place down through the years for no particular reason except I guess to be groovy. She came out as “lesbian” or something a few years ago, but she has always loved the cock, so that’s a lie.
Now she’s a Mom, off drugs and done slutting around on the Cock Carousel or Pussy Carousel or whatever, had a baby with some White dude, and she’s a nice, conservative Mom, I kid you not. No really. A nice girl you want to bring home to Mom. Against porn and slutting and doping and all that degenerate stuff. Yet another reformed sinner that found redemption, except this time in the Alt Right instead of Our Lord.
The silliest part of this whole interview which takes up most of it is that Tia Tequila, who is not even White is actually a gook, is all down with White nationalism or White supremacism or whatever the Alt Right does. So she’s a Viet Nazi. Actually a Viet Nazi who is psychotic and harbors the delusion that she is White.
I knew Asian girls had an inferiority complex, but come on. She goes on through most of this interview talking about being White, the White race, White genocide, bla, bla, all the White nationalist talking points. Tia the White nationalist! Except for that one trivial thing, you know, her not being White and all that. But no matter, hand wave. She thinks she’s White, so she’s White. I think I’m a giraffe, so tomorrow I will start eating leaves off trees. I hope they don’t arrest me.
Preposterously, the interviewers, apparently entranced by the pussy, go along with this facade of Gook as White Woman. Look Tila, I love Viet women, I really do. But they ain’t White, ok?
I have no idea why she is doing this.
The whole Alt Right is going along with this silliness. “Yes!” they scream with their dicks in their hands, “Tila is White!” I think the only reason they say this is because they are caught in a perpetual masturbatory trance about this bimbo, but hey. Any real White nationalists know that’s she’s obviously a gook, yeah, a hot one, but a gook fish-head nonetheless.
Gooks are pretty cute, but they ain’t White. If you let the gooks identify as White, your White genocide with happen faster than a bullet train, as most White guys will trade in your typical BPD/NPD/ASPD White woman for a Dragon Lady/China faster than a Manhattan minute. So I guess these Alt Right guys are cool with a White/Asian super-race extincting the White race? I would be, as the Asians would improve the stock, but it does run into the usual genocide question.
I asked Robert about this ridiculous interview, and he told me that Tila says her skin is White so she says she is White. Sorry, homegirl, that line don’t play with the Nazis. They ain’t fooled by such sophistry. Gooks are as much of a treat to the integrity of the White race as Mestizos or Blacks or whoever. Probably worse due to the White man’s tendency towards Rice King transformation.
Anyway, for your entertainment, the most preposterous interview Robert ever did with his silliest guest ever. Tia Tequila, Presente!
## Robert Stark interviews Tila Tequila
Robert Stark and co-host Alex von Goldstein talk to Tila Tequila
Topics include:
How Tila was the first person to catapult social media into what it is today.
How Tila became disillusioned with the degeneracy and emptiness of Hollywood.
Tila’s response to people who say she is a hypocrite for speaking out against degeneracy.
Blackmail, character assassinations, and censorship in Hollywood.
Meditation and spirituality.
Conspiracy Theories & The Green Pill.
How Tila was the first celebrity to openly endorse Donald Trump.
The Japanese Vaporwave Donald Trump Commercial.
How Tila’s views have evolved and her interest in the Alt-Right.
How Tila’s original fans have reacted to her views and her new fans on the Alt-Right.
How becoming a mother has changed her outlook on life.
How Tila’s Normie friends have reacted to her views.
Trolling and Meme Culture.
Tila’s upcoming appearance at the National Policy Institute in D.C.
## Repost: Which Rock Stars Are Gay?
This has long been one of the most popular posts on this site, which is a bit shameful, but then again, you can’t compromise success. This post got ~1,700 hits today, which is very high for a single post. A lot of them were coming in from search engines with the words “Kenny Chesney gay.” So there must be something floating around ab out whether Chesney is gay or not, but Chesney is a very problematic case and he is almost certainly not a gay man although the rumors never seem to stop. I added some new stuff to the post and anyway, a post this popular deserves a repost.
I think this post is one of the most accurate posts on this subject anywhere on the Net. I spent a of time on this, and many cases of false rumors are noted. Readers criticize this post on the basis of “Who cares whether some star is gay or not!?” However, the hard truth is that many people are very interested in this sort of thing along with the lives of celebrities in general.
The question is not necessarily anti-gay either because the people most fascinated by this question seem to be gay men and lesbians themselves, who I might note are also some of the best at sorting out the true versus untrue rumors.
I have heard charges that gays are bad sources for this sort of thing and that they will often make things up out of thin air just to increase their numbers, but that is just not true. If you want to know the lowdown on whether someone is gay or not, go to gay and lesbian boards, and they will have the dirty on just about everyone. And if the gays say that some rock star or politician has been seen in gay bars, is known to have a boyfriend or if some gay man claims to have sex with the person in question, the charge is almost always completely true.
Sure, a lot of people have said I was gay in my life, but they never presented any evidence to that effect.
No one has ever said that I frequent gay bars or named a bar that I frequent. This is because with the exception of one occasion, I have never been in a gay bar, although I did go to a gay rock concert though but that was because my semi-famous rock star girlfriend was playing at the show (they had straight bands playing too).
No one has ever said that I have a male lover except for my Grandma who accused my roommate of being my boyfriend! Some very nasty idiots have made ugly accusations that some of my male friends were actually my lovers, but they never offered any evidence to back up the charge because there is no evidence to offer as I have never had sex with any of my male friends, almost all of whom were heterosexual when I was hanging around with them anyway.
One of my best friends turned bisexual one me, and it made me so angry that I pretty much ended the friendship right then and there. I don’t want to associate with guys who do that sort of thing, and it never works anyway because gay and bi men cannot really be friends with straight men. I will leave it to you to guess why that is so, but I’m sure you can come up with some obvious theories. Perhaps I will discuss this in another post.
No gay man has ever come forward anywhere and claimed that I had sex with him and that is because there is no one to come forward because such a man does not even exist .
Especially in the case of politicians, gays are very cautious about doing the research needed to out anti-gay politicians.
Groupie boards have also been criticized as inaccurate but in general, reports about the sexual habits of various rock stars from groupies are usually very accurate. They simply do not make up lies about the sexuality of various stars.
As far as invading their privacy, these rock stars forfeited their right to privacy as soon as they got famous. This is pretty much true about anyone who is in the news a lot.
It might seem hard to believe that any of them are, but there have long been rumors about a number of them. Let’s go through the list.
A word about bisexual men. Unfortunately, bisexuality is very common, and I would say that after 40 years of observing males from even the point of view of a straight male that male bisexual behavior is much more common than nearly any straight person realizes.
I figure that for every one gay man, there are eight men with a bisexual orientation of various types and varieties. It is a truism with bisexuals that most lean one way or another. Very few men with a bisexual orientation are completely 50-50 in their attractions – only 5% could be described that way. Furthermore, only 16% of men with a bisexual orientation lean gay. 70% lean straight, and 75% of bisexual men are maximally attracted to women.
So for men with a bisexual orientation, the chart looks like this:
Maximally attracted to females: 75%
Lean Straight: 70%
Lean Gay: 16%
Maximally attracted to males: 15%
Full bisexual (50-50) 5%
50 Cent: Lil Kim’s boyfriend says he is on the downlow.
Damon Albarn (Blur): Possible bisexual tendencies.
Phil Anselmo (Pantera): Persistent rumors of bisexuality.
Billie Joe Armstrong (Green Day): Openly bisexual.
Lance Bass (‘N Sync): Either openly gay or deeply closeted, depending on who you talk to.
Marc Bolan (T. Rex): Supposedly out bisexual, truth unknown.
Bono (U2): Rumored bisexual, huge pussy hound, but another male musician claims he had sex with Bono once. Basically heterosexual.
Roddy Bottom (Faith No More): Openly gay.
David Bowie: Former bisexual, now identifies as straight. Massive pussy hound, basically heterosexual.
Boy George: Openly gay.
Kenny Chesney: Reportedly long known to be gay, but deeply closeted due to his country music fanbase. Renee Zellweger was his beard, but she divorced him after only four months of marriage due to “fraud.” On the other hand, in interviews, he says he is straight, is hurt by gay rumors and claims to have had sex with over 100 women, which, if true, is certainly not the behavior of a gay man. Very strange case in much need of further research.
Sean “Puffy” Combs: Unknown. What a bizarre rumor.
Warren Cuccurullo (Missing Persons): Probably bisexual. Has made several porn videos for the gay market (!?), including a few where he is jerking off and one where he is shoving a pink dildo up his ass (!?). He also posed on the cover of the Brazilian gay magazine G (!?).
Dave Davies (Kinks): Openly bisexual.
Ray Davies (Kinks): Basically heterosexual, experimented with men a bit.
Jonathan Davis (Korn): Bad rumor.
Ronnie James Dio: Straight, bad rumor.
Dr. Dre: Said to be gay and deeply closeted for years.
Ghall (Gorgoroth): Reputed to be gay and said to have a boyfriend who is a male model. Probably true.
Jay Gordon (Orgy): Bisexual tendencies.
Stone Gossard (Pearl Jam): Widely rumored to be a closeted bisexual.
Perry Ferrell (Jane’s Addiction/Porno for Pyros): Openly bisexual.
Ace Frehley (KISS): Straight, experimented with homosexuality a bit.
Rob Halford (Judas Priest): Openly gay.
Kirk Hammett (Metallica): Reportedly out bisexual. Swinger, frequents sex clubs with his wife.
Michael Hutchinson (Xtasy): Straight but said to have experimented with men.
Billy Idol: Basically a straight poon hound, but once he was seen in a bed having sex with a man.
Enrique Iglesias: Unknown.
Michael Jackson: Definitely a gay pedophile or hebephile.
Mick Jagger: Heterosexual, huge pussy hound, rumored to have sex with men one or more times.
Jay-Z: Lil Kim’s boyfriend says he’s on the downlow.
Elton John: Openly gay.
Holly Johnson (Frankie Goes to Hollywood): Known to be gay.
Al Jourgensen (Ministry): Said to be probably bisexual.
Anthony Keidis (Red Hot Chili Peppers): Rumored to be bisexual, false rumor.
Little Richard: Often thought to be gay and frequently calls himself gay, but actually probably bisexual.
LL Cool J: Lil Kim’s boyfriend says he’s on the downlow.
Loon: There is said to be an underground sex tape of him having anal sex with another rap star, P. Diddy.
Marilyn Manson: Reportedly out bisexual, however evidence is lacking. Basically heterosexual.
Paul Masvidal (Cynic): Openly gay.
Ricky Martin: Openly gay.
Maxwell: Rumored to be gay. Latest album was shelved by his record company because they were upset by all the gay references.
Mark McGrath (Sugar Ray): Bisexual.
Meegs (Coal Chamber): Possibly bisexual.
Freddie Mercury (Queen): Supposedly bisexual, actually gay.
Method Man: Rumored to be gay. Q-Tip is his possible boyfriend.
George Michael (Wham): Openly gay.
Brian Molko (Placebo): Openly bisexual.
Steven Morrissey (The Smiths): Obviously gay but closeted.
Bob Mould (Husker Du): Openly gay.
Dave Navarro (Jane’s Addiction, Red Hot Chili Peppers): Openly bisexual.
P. Diddy: There is said to be an underground sex tape of him having anal sex with another rap star, Loon.
Mike Patton (Faith No More): Widely rumored to be bisexual.
Joe Perry (Aerosmith): Rumored bisexual, false rumor. Pussy hound. Basically heterosexual.
The Pet Shop Boys: Openly gay.
Iggy Pop: Supposedly an out bisexual, but that is actually a completely false rumor.
Prince: Completely heterosexual, even if many find that incomprehensible. Insatiable pussy hound. Continuous gay rumors are due to his gender style, not his sexual orientation.
Q-Tip: Reputed to be gay. His rap lyrics are supposedly full of gay references. Boyfriend may be Method Man.
Redman: Reputed to be gay.
Lou Reed: Out bisexual, later identified as straight.
Sean Reinert (Cynic): Openly gay.
Nick Rhodes (Duran Duran): Rumored to be bisexual, said to share his male lover with his wife. Probably true.
Busta Rhymes: Reputed to be gay.
Ricki Rockett (Poison): Rumored bisexual, false rumor.
Henry Rollins (Black Flag): Bizarrely enough, there have been rumors about him for years. Unknown, but he has had many girlfriends over the years. This may just be a bad rumor, but people who knew him back when he was a starving musician in the New York East Village music scene in the mid to late 1970’s say he was well known to be bisexual to the point of being out about it. The rumors appear to stem from this period in his life. Definitely a mystery.
Gavin Rossdale (Bush): Rumored to be bisexual.
Rostam (Vampire Weekend): Openly gay.
David Lee Roth (Van Halen): Longstanding, persistent and wide rumors that he is bisexual, however these may be false rumors and have more to do with his gender behavior than his sexuality. Says he is straight in interviews. However, his bandmates, when asked if he is bisexual, say, “Dave is into a bit of everything.” Heterosexual poon hound who stages orgies at his mansion and often holes up there with a small harem. Was known to take on mother-daughter groupie teams!
Ja Rule: Lil Kim’s boyfriend says he’s on the downlow.
Fred Schneider (B-52’s): Unknown.
Pat Smear (Germs, Foo Fighters): Openly bisexual.
Robert Smith (Cure): Rumored bisexual, unknown.
Billy Squier: Unknown.
Paul Stanley (KISS): Married, two kids, but is apparently bisexual. He was also one of the biggest pussy hounds in all rock and roll. Although some vigorously dispute the charge, Ace Frehley, Frehley’s wife, the rock groupie site on the web (which is almost always correct), and two people in the music industry have all said he is bisexual. He is very much in the closet about it. I would say he leans straight though, looking at all of his womanizing.
Al Stewart: Unknown.
Rod Stewart: Bisexual rumors, never proven but suggestive. Major pussy hound. Basically heterosexual.
Michael Stipe (R.E.M): Openly bisexual or maybe gay.
Justin Timberlake (‘N Sync): Rumored to be bisexual.
Pete Townshend (The Who): Supposedly out bisexual. Strange rumor.
Steve Tyler (Aerosmith): Rumored bisexual, false rumor. Huge pussy hound. Basically heterosexual.
Luther Vandross: Long known to be gay in the Black community and of course with his band-mates. Deeply closeted.
Phil Varone (Skid Row): Bisexual.
Sid Vicious: Supposedly out bisexual, but once again looks like a bad rumor.
Scott Weiland: Rumored to be bisexual.
Yogi (Buckcherry): Rumored to be bisexual.
## Women
Christina Aguilera: Open bisexual.
Joan Armatrading: Either lesbian or bisexual, possibly true.
Joan Baez: Bisexual, probably true.
Toni Braxton: Lesbian, closeted. Had an affair with Courtney Love.
Tracy Chapman: Out lesbian.
Sheryl Crow: Bisexual, apparently true.
Ani DiFranco: Out bisexual.
Melissa Etheridge: Out lesbian.
Marianne Faithfull: Out bisexual.
Whitney Houston: Straight but experimented with women.
Chrissie Hynde (Pretenders): Rumored bisexual.
Janis Ian: Out bisexual.
Janet Jackson: Definitely bisexual, closeted.
Joan Jett: Definitely lesbian, but she does not discuss it.
Grace Jones: Out bisexual.
Janis Joplin: Out bisexual.
Wynona Judd: Unknown.
Alicia Keys: Closeted lesbian, tries to deflect rumors by making homophobic comments, has a male beard.
K. D. Lang: Out lesbian.
Courtney Love (Hole): Openly bisexual. Had an affair with Winona Ryder.
Madonna: Out bisexual. Has had affairs with other celebrity women.
Me’shell N’Degeocell: Out bisexual.
Joni Mitchell: Out bisexual.
Queen Latifah: Lesbian, deeply closeted.
Olivia Newton-John: Rumored bisexual.
Stevie Nicks: Well known to be bisexual, closeted.
Sinead O’Connor: Bisexual or lesbian, apparently true.
Dolly Parton: Lesbian, closeted.
Bonnie Raitt: Straight-leaning bisexual, apparently true.
Rhianna: Rumored bisexual.
Linda Ronstadt: Lesbian or bisexual, apparently true.
Winona Ryder: Confirmed bisexual. Had an affair with Courtney Love.
Dusty Springfield: Openly lesbian.
## All Men Are Pedophiles
Brooke Shields, age 16, from one of her famous movies. According to a vast number of idiotic females and mangina/White knight/Save-a-ho gender sellout “men,” if you as a man get turned on by the girl in this photo, that proves that you are a “pedophile.”
This is because the female in the photo above is supposed a “child,” and that means you get turned on by “children.” I have been looking at that photo for some time now, and whatever it is that is in that photo, it sure as Hell isn’t a child. I have no idea what that female Homo Sapiens is.
She’s not a child. Is she an adult? She doesn’t look much different from many adults 2-3 years her junior, so she sure looks like an adult. What about her mind and maturity? Well, that female is probably as mature as a male of at least 20, because adolescent and college aged females are often dramatically more emotionally mature than their male peers. I am going to pass on whether or not she is an adult. In the UK, for certain things, she sure would be. For instance, in the UK, this female would be judged a woman, and she could have legal sex with any male adult of any age, and she might just want to do just that.
But I know for sure that she’s not a kid.
I don’t know if she’s an adult either to be honest, but she sure is getting there. Party of me wants to call that female a woman. A very, very, very young woman for sure, but a woman nevertheless. And many people would agree with me. Note the widespread use of “young man” and “young woman” when adults address adolescents around this age, as well they should. Do we call little boys and little girls young men and young women? Of course not, or you shouldn’t because it’s silly. A kid is a kid. Don’t call kids adults. It’s idiotic.
Is the female above mature? Of course not. This is about as young as a woman gets, you know. The very youngest women of all are of course the least mature. That’s always the case.
Probably the best way to describe this female is to say that she’s not a child, and she’s not exactly an adult either. She’s somewhere in between, floating around.
I think whether or not this female is a child, adult or in between is not really a scientific question. It is probably more in the realm of sociology or even philosophy. Science cannot answer such things very well, despite the widespread idiotic notion that it can.
Anyway, 80% of US society says if this chick turns you on, you’re a pedophile.
Not if you print out her picture and jerk off to it. Not if you try to fuck her. Not if you do fuck her. But instead if you think about her in some illegal way. Indeed, society is so stupid nowadays that most “adults” believe in the existence of thought crimes.
Let me tell you something. Every single man on Earth is turned on by this female.
If he’s not, he must be at least one of the options below:
• Lying
• Blind
• Gay | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.15593701601028442, "perplexity": 5542.5516495143875}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-21/segments/1620243988966.82/warc/CC-MAIN-20210509092814-20210509122814-00252.warc.gz"} |
http://boblef.hatenablog.com/entry/2017/07/17/Private_college | Private college
I've spent the Private college for 2weeks.
I'd a tons of works such as assignments,presentation and two kind of exams.
These two weeks are called 1st term,and we studied basically parts of IT which are necessary to bacome an IT engineer like Binary,Quad,Octal,Hexa-Decimal and something which are about what is computer like that.
It was busier than I expected,but it was also exsiting to study its.
When I was in a University,I didn't know why I was in there,why I was studying IT and what would I become.
So I quitted.
However now,I'm sure I know the reason why I'm in the college.
Because I'm interesting about IT and I would like to be IT engineer.
7月4日より専門学校が始まりまして、あまり大きくない学校であるため同級生の人数はそんなに多くありませんが、私を含め日本人は３人で、もちろんネイティブもいますし22歳で会社経営してる人も同級生でいます。
なんならもっと分からないかもしれません。
その分家に帰ってから自分で調べて復習して、その後次の日の予習、宿題があれば宿題といった感じで、この前プレゼンテーションがありました。
トピックはinput deviceとoutput device。
それから、2週間過ぎ落ち着いてきたので、プログラミングもどんどん先取りして勉強しています。
BUTAKIMCHI
PASTA
SHOGAYAKI
では。
Bob | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.811866283416748, "perplexity": 3363.820810580547}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-47/segments/1510934805114.42/warc/CC-MAIN-20171118225302-20171119005302-00484.warc.gz"} |
http://quant.stackexchange.com/questions/7214/nyse-binary-data-convert-to-ascii/7220 | # NYSE binary data, convert to ASCII
The data product "TAQ NYSE Order Imbalances" from the New York Stock Exchange is in a format that is described pretty well in sections 4.8, 4.9, 4.10, and 5 of the document "NYSE Order Imbalances Client Specification", version 1.12, q.v. Briefly, it's a mix of ASCII and binary: stock symbols, for example, are in plain text, but padded by null bytes, while numerical fields are in binary digits represented by a byte with that binary value. All fields are fixed-width, so data rows simply follow one another.
Does anyone know how to convert this to, say, a comma-separated file?
-
(From the FAQ list: "We can answer questions for software packages that are specific to quantitative finance". Just in case anyone's thinking of closing this as off-topic. (But if you think it'd have a better chance of being answered elsewhere, please let me know!)) – msh210 Feb 4 '13 at 20:37
This is the multicast data, ie the live feed. This is not the historical data. – chrisaycock Feb 4 '13 at 20:59
@chrisaycock, yes, but the format is similar and the live data's specification explains it better. – msh210 Feb 4 '13 at 21:00
I assume then you have a file that's in this format. In that case, you'll need to read the message header to determine the type, and then interpret the type from there as an unpadded struct. Because this is a compact binary file, you'll likely need to write your decoder in C, or at least some language that can specify memory layout and field size. – chrisaycock Feb 4 '13 at 21:02
@chrisaycock (1) Part of your latest comment ("interpret... struct") is Greek to me. If it's still relevant after you read the rest of this comment, then can you explain, please? (2) I am not a programmer. In particular, I don't know C. (3) As to the first part of your comment, do you mean the first few bytes of the file? (a) I don't think the data file uses that sort of marker. I think it strictly follows the format specified in the linked-to documentation and summarized in my question. (b) I don't know how to read those bytes. – msh210 Feb 4 '13 at 21:06
I think you do not need to be a "Systems Programmer", certainly not an experienced one, to solve this problem:
1) Focus on the header, its your legend to the file structure. It describes the format and essentially already tells you how to decode the following messages.
2) Depending on your choice of language you then process each message in binary format and convert each item to the numeric format. In C#, some use "BitConverter" but obviously C# is not the language of choice here. If you can tell me which specific language you use to make the conversion then that would be helpful. A lot of people use Python to convert this kind of stuff to a higher level text based format such as csv or any delimiter-delimited structure.
3) Before you convert you may want to think carefully whether you may want to perform operations on the byte array representations of your numeric values (I am not familiar with your mentioned specific feed, though some feeds only output the "alpha" rather than full spread, for example, thus you need to perform add/subtract operations which can in certain cases be more optimal to perform on the byte array itself). Here is an example : http://stackoverflow.com/questions/3641274/c-sharp-int-byte-conversion
Here are couple Python examples just to show you how a simple byte[]-> int conversion could be done:
http://stackoverflow.com/questions/386753/how-do-i-convert-part-of-a-python-tuple-byte-array-into-an-integer
http://stackoverflow.com/questions/444591/convert-a-string-of-bytes-into-an-int-python
P.S.: It won't help you but I find mixed message formats very inefficient but that is not your fault. Most efficient streams only ship byte arrays, nothing else. A symbol should anyway never be in string format internally, but rather be assigned an int32 or int64 code. Mapping internally is much faster than converting each symbol of each message from byte array to string. Also, even if the symbol is decoded in ASCII that is very inefficient and blows up message size.
-
Thanks! Re (1), I don't have the impression there's a file header. Re (2), sed would be great. – msh210 Feb 5 '13 at 17:11
I doubt sed gets you what you look for. Sed is used To parse text, you mentioned your stream contains byte arrays. To need to know what each field represents from the documentation you mentioned. Then you simply google how you can make the conversion in ,for example Pearl or Python, to the variable type targeted. Really not that hard if you ask me. – Matt Wolf Feb 5 '13 at 18:38
Not sure what you are actually struggling with. You laid out the 40 bytes per message in much detail in SO (is saw your question there). I could write you a program in c# in less than an hour to get the job done. I make the assumption here the source is also a file of binary nature correct? – Matt Wolf Feb 5 '13 at 18:45
I'm not sure what you mean by "the source is also a file of binary nature". The problem I'm having (which, yeah, I guess I explained better on SO) is parsing the bytes. I guess, as someone mentioned there, od would help... but I'm on Windows. I also don't have the wherewithal to hire you to write a C# program for me (or the trust to run an executable you send me). I will keep looking around.... – msh210 Feb 5 '13 at 18:51
I wrote the pack R package (based on Perl's pack function), to do this for opentick (now defunct) data. You can look at the opentick package (in the CRAN archives) to see how I used it.
I just noticed that you said you're comfortable with Perl in your SO post. In that case, I'd recommend you use Perl's unpack function.
-
Thank you! 15ch – msh210 Feb 5 '13 at 20:16 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.39398571848869324, "perplexity": 1228.8307436887224}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-32/segments/1438042988840.31/warc/CC-MAIN-20150728002308-00016-ip-10-236-191-2.ec2.internal.warc.gz"} |
https://worldwidescience.org/topicpages/s/subacromial+syndrome+rotator.html | #### Sample records for subacromial syndrome rotator
1. Subacromial impingement syndrome
NARCIS (Netherlands)
Umer, M.; Qadir, I.; Azam, M.
2012-01-01
Subacromial impingement syndrome (SAIS) represents a spectrum of pathology ranging from subacromial bursitis to rotator cuff tendinopathy and full-thickness rotator cuff tears. The relationship between subacromial impingement and rotator cuff disease in the etiology of rotator cuff injury is a
2. Subacromial impingement syndrome
OpenAIRE
Masood Umer; Irfan Qadir; Mohsin Azam
2012-01-01
Subacromial impingement syndrome (SAIS) represents a spectrum of pathology ranging from subacromial bursitis to rotator cuff tendinopathy and full-thickness rotator cuff tears. The relationship between subacromial impingement and rotator cuff disease in the etiology of rotator cuff injury is a matter of debate. However, the etiology is multi-factorial, and it has been attributed to both extrinsic and intrinsic mechanisms. Management includes physical therapy, injections, and, for some patient...
3. Subacromial impingement syndrome.
Science.gov (United States)
Umer, Masood; Qadir, Irfan; Azam, Mohsin
2012-05-09
Subacromial impingement syndrome (SAIS) represents a spectrum of pathology ranging from subacromial bursitis to rotator cuff tendinopathy and full-thickness rotator cuff tears. The relationship between subacromial impingement and rotator cuff disease in the etiology of rotator cuff injury is a matter of debate. However, the etiology is multi-factorial, and it has been attributed to both extrinsic and intrinsic mechanisms. Management includes physical therapy, injections, and, for some patients, surgery. No high-quality randomized controlled trials are available so far to provide possible evidence for differences in outcome of different treatment strategies. There remains a need for high-quality clinical research on the diagnosis and treatment of SAIS.
4. Subacromial impingement syndrome
Directory of Open Access Journals (Sweden)
Masood Umer
2012-05-01
Full Text Available Subacromial impingement syndrome (SAIS represents a spectrum of pathology ranging from subacromial bursitis to rotator cuff tendinopathy and full-thickness rotator cuff tears. The relationship between subacromial impingement and rotator cuff disease in the etiology of rotator cuff injury is a matter of debate. However the etiology is multi-factorial, and has been attributed to both extrinsic and intrinsic mechanisms. Management includes physical therapy, injections, and, for some patients, surgery. No high-quality RCTs are available so far to provide possible evidence for differences in outcome of different treatment strategies. There remains a need for high-quality clinical research on the diagnosis and treatment of SAIS.
5. The clinical utility of ultrasonography for rotator cuff disease, shoulder impingement syndrome and subacromial bursitis.
Science.gov (United States)
Awerbuch, Mark S
2008-01-07
Periarticular shoulder disorders are common in clinical practice, and diagnosis is often difficult. Medicare statistics indicate that between 2001 and 2006 the use of diagnostic shoulder ultrasonography increased significantly. Rotator cuff disease, shoulder impingement syndrome and subacromial bursitis are among the most common diagnoses reported on shoulder ultrasonography. Shoulder ultrasonography is useful in the diagnosis of full thickness tears, but its utility for other rotator cuff disorders, shoulder impingement syndrome and subacromial bursitis is less well established.
6. RIGID TAPE VERSUS KINESIO TAPE ON SCAPULAR ROTATION AND FORWARD HEAD ANGLE IN SUBACROMIAL IMPINGEMENT SYNDROME
OpenAIRE
Eman A. Embaby; Eman M.A. Abdalgwad
2016-01-01
Background: Rigid and kinesio taping is commonly used in the rehabilitation and prevention of subacromial impingement syndrome (SIS). It is proposed to have positive effects on shoulder function and scapular kinematics. However, there is a paucity of literature regarding the effectiveness of rigid versus elastic taping on scapular upward rotation and forward head posture (FHP), which is commonly adopted in SIS. Purpose: This study was designed to investigate the effect of taping with post...
7. Current Status of Open Surgical Treatment Protocols for Subacromial Impingement Syndrome Associated with Rotator Tear
Directory of Open Access Journals (Sweden)
Oktay Gazi
2012-06-01
Full Text Available Objective: The aim of this study was to evaluate the recent treatment protocols for Neer stage III subacromial impingement syndrome with open anterior acromioplasty and rotator cuff repair. Material and Methods: Twenty-two patients (8 males, 14 females; mean age: 52.9±10.2 who were diagnosed with a rotator cuff tear based on clinical and radiological findings between 2009 and 2010 participated in the study.. We used the open surgical decompression technique which was previously described by Neer. The ruptured tendon ends were isolated and were fixed to the bones with appropriate suture anchors and transosseoz sutures. Preoperative, postoperative and the final follow-up Constant and UCLA shoulder scores were evaluated. Results: The mean preoperative Constant score was 34.4±6.6 and UCLA score was 13.8±3.3. The mean postoperative Constant score was 73±7.6 and UCLA score was 31.7±3.3. Significant improvement was observed in postoperative shoulder scores (p<0.01 and postoperative shoulder range of motion in all patients (p<0.01. Conclusion: Currently, clinical and functional results of open and arthroscopic subacromial rotator cuff decompression are similar. However, many surgeons prefer the open method and achieve successful results. (The Me di cal Bul le tin of Ha se ki 2012; 50: 59-63
8. Subacromial Impingement Syndrome Caused by a Voluminous Subdeltoid Lipoma
OpenAIRE
Jean-Christophe Murray; Stéphane Pelet
2014-01-01
Subacromial impingement syndrome is a clinical diagnosis encompassing a spectrum of possible etiologies, including subacromial bursitis, rotator cuff tendinopathy, and partial- to full-thickness rotator cuff tears. This report presents an unusual case of subdeltoid lipoma causing extrinsic compression and subacromial impingement syndrome. The patient, a 60-year-old man, presented to our institution with a few years' history of nontraumatic, posteriorly localized throbbing pain in his right sh...
9. Guideline for diagnosis and treatment of subacromial pain syndrome
NARCIS (Netherlands)
Diercks, Ronald; Bron, Carel; Dorrestijn, Oscar; Meskers, Carel; Naber, René; de Ruiter, Tjerk; Willems, Jaap; Winters, Jan; van der Woude, Henk Jan
Treatment of "subacromial impingement syndrome" of the shoulder has changed drastically in the past decade. The anatomical explanation as "impingement" of the rotator cuff is not sufficient to cover the pathology. "Subacromial pain syndrome", SAPS, describes the condition better. A working group
10. Patients With Impingement Syndrome With and Without Rotator Cuff Tears Do Well 20 Years After Arthroscopic Subacromial Decompression.
Science.gov (United States)
Jaeger, Moritz; Berndt, Thomas; Rühmann, Oliver; Lerch, Solveig
2016-03-01
11. Injection of the subacromial bursa in patients with rotator cuff syndrome: a prospective, randomized study comparing the effectiveness of different routes.
Science.gov (United States)
Marder, Richard A; Kim, Sunny H; Labson, Jerry D; Hunter, John C
2012-08-15
Rotator cuff syndrome is often treated with subacromial injection of corticosteroid and local anesthetic. It has not been established if the common injection routes of the bursa are equally accurate. We conducted a prospective clinical trial involving seventy-five shoulders in seventy-five patients who were randomly assigned to receive a subacromial injection through an anterior, lateral, or posterior route with respect to the acromion. An experienced physician performed the injections, which contained radiopaque contrast medium, corticosteroid, and local anesthetic. After the injection, a musculoskeletal radiologist, blinded to the injection route, interpreted all of the radiographs. The rate of accuracy varied with the route of injection, with a rate of 56% for the posterior route, 84% for the anterior route, and 92% for the lateral route (p = 0.006; chi-square test). The accuracy of injection through the posterior route was significantly lower than that through either the anterior or the lateral route (p bursa in females.
12. Subacromial lipoma causing shoulder impingement syndrome.
Science.gov (United States)
Sucuoglu, Hamza; Akgun, Kenan
2017-01-01
Subacromial lipoma represents a rare cause of subacromial impingement syndrome (SIS). A 49-year-old male patient presented to clinic with progressive right shoulder pain and limited movement, ongoing for approximately 1 month. Magnetic resonance imaging (MRI) revealed a lesion, compatible with lipoma, extending through subacromial space and pressing on supraspinatus muscle. After histopathological verification of lipoma, mass was excised. Postoperatively, patient completed 1 month physical therapy and rehabilitation program. Patient was free of pain at 4-month follow-up. Subacromial lipoma should be included in differential diagnosis of SIS for patients unresponsive to conservative treatment; MRI is very useful to determine precise etiology and inform surgical treatment.
13. Subacromial impingement syndrome caused by a voluminous subdeltoid lipoma.
Science.gov (United States)
Murray, Jean-Christophe; Pelet, Stéphane
2014-01-01
Subacromial impingement syndrome is a clinical diagnosis encompassing a spectrum of possible etiologies, including subacromial bursitis, rotator cuff tendinopathy, and partial- to full-thickness rotator cuff tears. This report presents an unusual case of subdeltoid lipoma causing extrinsic compression and subacromial impingement syndrome. The patient, a 60-year-old man, presented to our institution with a few years' history of nontraumatic, posteriorly localized throbbing pain in his right shoulder. Despite a well-followed 6-months physiotherapy program, the patient was still suffering from his right shoulder. The MRI scan revealed a well-circumscribed 6 cm × 2 cm × 5 cm homogenous lesion compatible with a subdeltoid intermuscular lipoma. The mass was excised en bloc, and subsequent histopathologic examination confirmed a benign lipoma. At 6-months follow-up, the patient was asymptomatic with a complete return to his activities. Based on this case and a review of the literature, a subacromial lipoma has to be included in the differential diagnosis of a subacromial impingement syndrome refractory to nonoperative treatment. Complementary imaging modalities are required only after a failed conservative management to assess the exact etiology and successfully direct the surgical treatment.
14. Subacromial Impingement Syndrome Caused by a Voluminous Subdeltoid Lipoma
Directory of Open Access Journals (Sweden)
Jean-Christophe Murray
2014-01-01
Full Text Available Subacromial impingement syndrome is a clinical diagnosis encompassing a spectrum of possible etiologies, including subacromial bursitis, rotator cuff tendinopathy, and partial- to full-thickness rotator cuff tears. This report presents an unusual case of subdeltoid lipoma causing extrinsic compression and subacromial impingement syndrome. The patient, a 60-year-old man, presented to our institution with a few years' history of nontraumatic, posteriorly localized throbbing pain in his right shoulder. Despite a well-followed 6-months physiotherapy program, the patient was still suffering from his right shoulder. The MRI scan revealed a well-circumscribed 6 cm × 2 cm × 5 cm homogenous lesion compatible with a subdeltoid intermuscular lipoma. The mass was excised en bloc, and subsequent histopathologic examination confirmed a benign lipoma. At 6-months follow-up, the patient was asymptomatic with a complete return to his activities. Based on this case and a review of the literature, a subacromial lipoma has to be included in the differential diagnosis of a subacromial impingement syndrome refractory to nonoperative treatment. Complementary imaging modalities are required only after a failed conservative management to assess the exact etiology and successfully direct the surgical treatment.
15. Subacromial injections of corticosteroids and xylocaine for painful subacromial impingement syndrome.
Science.gov (United States)
Yu, Chung-Ming; Chen, Chih-Hwa; Liu, Hsien-Tao; Dai, Ming-Hsun; Wang, I-Chun; Wang, Kun-Chung
2006-01-01
Subacromial impingement syndrome, with pain and limited motion, is a common disease encountered daily in clinics. This study determined the efficacy of subacromial injections of corticosteroids and local anesthesia for treatment of painful subacromial impingement syndrome. A total of 238 shoulders in 209 patients, with regular follow-up, were enrolled in this study. Mean patient age was 51 years (range 31-72 years). Each patient complained of shoulder pain with progressive motion limitation present for more than one month, which was not relieved by various nonsurgical treatments. The mean duration of symptoms before injection was five months (range 1-12 months). Each patient had a positive Neer impingement sign, Hawkins impingement sign, painful tendon sign, limited range of motion and did not show clinical evidence of a rotator cuff tear. Each patient was administered an injection of 1 ml of 2% Xylocaine and 1 ml of Rinderon suspension. A second injection was administered one week later for patients without obvious improvement. Following injections, patients were instructed to perform a home rehabilitation program for four weeks. Follow-up examinations were scheduled for one, two and four weeks, and three, six, nine and 12 months after injection. Outcome measures included the Constant-Murley score and shoulder range of motion. At follow-up four weeks after the first injection, 216 shoulders (91%) had satisfactory improvement in amount of pain and range of motion: mean improvements in the active range of motion of forward elevation, abduction, internal rotation and external rotation were 56 degrees, 48 degrees, 18 degrees and 22 degrees, respectively. However, at the first year follow-up, the satisfaction rate was slightly down at 88%, and 19 shoulders (8%; 16 patients) had recurrent pain and motion limitation after an average of 5.4 months (range 3-12 months). Each of these patients received another injection. Surgery was recommended for 22 shoulders (9%; 18
16. The molecular pathophysiology of subacromial bursitis in rotator cuff disease.
Science.gov (United States)
Blaine, Theodore A; Kim, Yang-Soo; Voloshin, Ilya; Chen, Darwin; Murakami, Koko; Chang, Seong-Sil; Winchester, Robert; Lee, Francis Y; O'keefe, Regis J; Bigliani, Louis U
2005-01-01
Little information exists on the molecular and biochemical pathophysiology of subacromial bursitis and rotator cuff disease. We investigated the pattern of expression of cytokines (interleukin [IL]-1beta, IL-1, IL-6, tumor necrosis factor [TNF] alpha, small inducible cytokines), metalloproteases, and cyclooxygenases in the subacromial bursa in patients with rotator cuff disease. Subacromial bursa specimens were prepared for molecular and biochemical analysis in patients undergoing shoulder surgery following an institutional review board-approved protocol. Specimens were analyzed for the presence of cytokines, metalloproteases, and cyclooxygenases by use of microarray for gene expression and immunohistocytochemistry. Microarray analysis for gene expression and immunohistochemistry demonstrated that the expression of several cytokine genes (TNF, IL-1alpha, IL-1beta, and IL-6) was increased in patients with subacromial bursitis compared with control specimens. Furthermore, the expression of metalloproteases (MMP-1 and MMP-9) and cyclooxygenases (COX-1 and COX-2) in the bursitis group was found to be increased as compared with controls. Although further investigation is required, these studies suggest that inflammation of the subacromial bursa does occur in patients with rotator cuff disease. These findings support the role of anti-inflammatory agents in the treatment of subacromial impingement and emphasize the importance of subacromial bursectomy to reduce inflammation in rotator cuff disease.
17. Internal- and External-Rotation Peak Toque in Little League Baseball Players With Subacromial Impingement Syndrome: Improved by Closed Kinetic Chain Shoulder Training.
Science.gov (United States)
Lee, Dong-Rour; Kim, Laurentius Jongsoon
2016-08-01
Many studies have explored closed kinetic chain (CKC) shoulder exercises (SEs) with a sling because they are safer and more effective than open-chain exercises, especially in early stages of treatment. However, the application of CKC SE in youth baseball players has rarely been attempted, although teenage baseball players also experience shoulder pain. To investigate the effects of CKC SE on the peak torque of shoulder internal rotation (IR) and external rotation (ER) in youth baseball players. Single-group pretest, posttest. Biomechanics laboratory. 23 Little League Baseball players with subacromial impingement syndrome. The CKC SE with a sling was CKC shoulder-flexion exercise, extension exercise, IR exercise, and ER exercise. This exercise regimen was conducted 2 or 3 times/wk for 8 wk. The peak torque of shoulder IR and ER was measured using an isokinetic dynamometer. Concentric shoulder rotation was performed, with 5 repetitions at an angular velocity of 60°/s and 15 at 180°/s. The IR and ER peak torque significantly increased at each angular velocity after the exercise program. In particular, the increase in IR and ER peak torque values was statistically significant at an angular velocity of 180°/s. CKC SE was effective in increasing shoulder IR and ER strength, demonstrating its potential benefits in the prevention and treatment of shoulder injury. In addition, increased IR peak torque appears to improve throwing velocity in baseball players.
18. Subacromial osteochondroma: A rare cause of impingement syndrome.
Science.gov (United States)
Çıtlak, Atilla; Akgün, Ulaş; Bulut, Tugrul; Aslan, Cihan; Mete, Berna Dirim; Şener, Muhittin
2015-01-01
Subacromial impingement syndrome is one of the most common disorders of shoulder. Scapula is a very rare site for osteochondromas, and osteochondromas arising under the acromion cause impingement syndrome. We presented 34-year old female patient with subacromial impingement syndrome secondary to osteochondroma. She had received conservative treatment several times in other clinics. The osteochondroma causing impingement was not diagnosed. Physical examination of the right shoulder revealed 90° flexion, 70° abduction, 20° external rotation and internal rotation to sacrum. X-ray, CT and MRI of the shoulder was obtained. Osteochondroma of the acromion (35×33×25mm) causing impingement was detected. The osteochondroma of acromion compressed, displaced and ruptured the supraspinatus tendon. Also an osseous prominence of glenoid was detected during shoulder arthroscopy, and it was removed arthroscopically. The giant osteochondroma of acromion could not remove arthroscopically due to the size of the lesion, and it was removed totally through a mini open approach. Histopathological examination confirmed the diagnosis of osteochondroma. Scapular, clavicular and humeral osteochondromas cause impingement syndrome. Osteochondroma should be treated with total excision. Recurrences can be seen due to insufficient removal of osteochondromas. We think that, total excision is important to prevent recurrence. Subacromial osteochondroma is a very rare cause of impingement syndrome, and if it isn't diagnosed early it limits shoulder movements, causes severe shoulder impingement and rotator cuff tear. The diagnosis of subacromial osteochondroma should be considered in any patient with shoulder impingement syndrome and good functional results can be expected following total excision. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
19. Guideline for diagnosis and treatment of subacromial pain syndrome: a multidisciplinary review by the Dutch Orthopaedic Association
NARCIS (Netherlands)
Diercks, R.; Bron, C.; Dorrestijn, O.; Meskers, C.; Naber, R.; Ruiter, T. de; Willems, J.; Winters, J.; Woude, H.J. van der; et al.,
2014-01-01
Treatment of "subacromial impingement syndrome" of the shoulder has changed drastically in the past decade. The anatomical explanation as "impingement" of the rotator cuff is not sufficient to cover the pathology. "Subacromial pain syndrome", SAPS, describes the condition better. A working group
20. EFFECT OF POSTURAL CORRECTION WITH DIFFERENT TAPING MATERIALS ON SCAPULAR KINEMATICS AND MYOELECTRIC ACTIVITIES OF SCAPULAR ROTATORS IN SUBACROMIAL IMPINGEMENT SYNDROME A RANDOMIZED PLACEBO-CONTROLLED TRIAL
Directory of Open Access Journals (Sweden)
2016-06-01
Full Text Available Background: Rigid and kinesio tapings are commonly used in the rehabilitation of subacromial impingement syndrome (SIS. Yet; the effect of postural correction with the two taping materials in SIS has not been extensively studied. The purpose of the study is to examine the effect of postural correction with two different taping materials on scapular kinematics and electromyography of scapular upward rotators in patients with SIS. Methods: Twenty female patients with SIS participated in this study. Their age ranged from 30-60 years. Participants were randomly assigned into: Group I (Kinesio tape, n=10 and Group II (rigid tape, n=10. Thoracic and scapular taping with posture correction was applied to both groups. Scapular upward rotation at 0˚, 60˚, 90˚ and 120˚ of shoulder elevation and the activity level of the upper fibers of trapezius (UT, lower fibers of trapezius (LT and serratus anterior (SA muscles were measured before and immediately after taping application. Results: Both taping materials significantly increased scapular upward rotation at 60°, 90° and 120° angles (P =.004,.002 and .047 respectively after the application of tape as compared to the before. In addition, significantly greater muscle activity of the LT and SA muscles (P =.027 and 0.05 respectively were demonstrated by the kinesio-taping group as compared to rigid taping group during real taping condition. Conclusion: Both taping materials are effective in restoring scapular kinematics. Furthermore, kinesio taping has a facilitatory effect on the LT and SA muscles. Kinesio taping may be considered an alternative to rigid taping in patients with SIS.
1. Proinflammatory cytokines and metalloproteases are expressed in the subacromial bursa in patients with rotator cuff disease.
Science.gov (United States)
Voloshin, Ilya; Gelinas, Jill; Maloney, Michael D; O'Keefe, Regis J; Bigliani, Louis U; Blaine, Theodore A
2005-09-01
The pathophysiology of subacromial impingement syndrome is poorly understood. We investigated the expression of inflammatory cytokines, metalloproteases, and the cyclooxygenases in the subacromial bursa in control patients and in patients with rotator cuff tear. Basic science evaluation. Eighteen patients undergoing shoulder surgery had a subacromial bursa biopsy examination. Patients were divided into 2 groups. Group I (study group) had 10 patients with a full-thickness rotator cuff tear (RCT). Group II (control group) had 8 patients. Seven of 8 underwent shoulder arthroscopy with anterior capsular reconstruction for instability; 1 of 8 underwent open reduction internal fixation for acute proximal humerus fracture. None of the patients in group II had any history of symptoms or signs consistent with subacromial impingement. H&E and immunohistochemical antibody (MMP-1, MMP-9, IL-1, IL-6, TNF-alpha, COX-1, and COX-2) stained specimens were examined by 2 blinded observers using a histologic scale (grade 0 = no staining to grade 4 = intense staining). Histologic evidence of inflammation was present in all patients with RCT (group I). No or mild inflammation was noted in group II. The average staining grade for inflammatory cytokines (IL-1, IL-6, TNF-alpha) and proteinases (MMP-1 and MMP-9) was significantly more pronounced in the RCT group (P bursa of patients with rotator cuff tear. These findings support the role of nonsteroidal anti-inflammatory drugs and corticosteroids in RCT treatment, and emphasize the importance of subacromial bursectomy to reduce inflammation in RCT surgery.
2. Fewer rotator cuff tears fifteen years after arthroscopic subacromial decompression.
Science.gov (United States)
Björnsson, Hanna; Norlin, Rolf; Knutsson, Anders; Adolfsson, Lars
2010-01-01
A successful clinical result is reported in 75% to 85% of impingement patients after arthroscopic subacromial decompression. The result is maintained over time, but few studies have investigated the integrity of the rotator cuff in these patients. Using ultrasonography, we examined the integrity of the rotator cuff in 70 patients 15 years after arthroscopic subacromial decompression. All patients had an intact rotator cuff at the index procedure. Tendons were still intact in 57 patients (82%), 10 (14%) had partial-thickness tears, and 3 (4%) had full-thickness tears. The total number of 18% tears (partial and full thickness) in this study, including patients clinically diagnosed with subacromial impingement at a mean age of 60 years, is unexpectedly low compared with 40% degenerative tears reported in asymptomatic adults of the same age. Arthroscopic subacromial decompression seems to reduce the prevalence of rotator cuff tears in impingement patients. This appears attributable to elimination of extrinsic factors such as mechanical wear and bursitis. The potential effect of surgery on intrinsic cuff degeneration is unknown, but intrinsic factors may explain tears still developing despite decompression. Level III, therapeutic study.
3. Blood supply of the subacromial bursa and rotator cuff tendons on the bursal side.
Science.gov (United States)
2017-07-01
Vascularity of the subacromial bursa and rotator cuff tendons is key factors in the pathogenesis of subacromial bursitis and impingement syndrome, rotator cuff tendinitis, and rotator cuff tears. The purpose of this study was to investigate and describe blood supply to the cranial and caudal parts of the subacromial bursa and the vascularity of the rotator cuff tendons on the bursal side. Fourteen fresh cadaveric shoulders from six females and eight males with a mean age of 71.7 (±10.8) years were studied. Before dissection, an arterial injection of 10% aqueous dispersion of latex was administered. Post-injection, the shoulders were fixed in an alcohol-formalin-glycerol solution. The cranial and caudal bursa of all specimens was mainly supplied by the thoracoacromial, suprascapular, and anterior and posterior circumflex humeral arteries. The cranial part of the bursa was supplied anteriorly by the thoracoacromial artery, and posteriorly and medially by the posterior circumflex humeral artery as far as the medial third. The caudal part received arterial blood anteriorly from the anterior circumflex humeral artery, and posteriorly and medially by the posterior circumflex humeral artery as far as the medial third of the caudal bursa. In addition, the suprascapular artery branched at the upper surface of the coracohumeral ligament, and the subcoracoid artery branched at the under surface of the same ligament. The subacromial bursa appears well vascularized. The results of the present investigation showed that blood supply to the subacromial bursa at the caudal part and rotator cuff tendons on the bursal side was linked to the same arteries. The subcoracoid artery supplied interval rotator structures close to the caudal bursa. It is the wish of the authors that this meticulous anatomical work will help surgeons in their day-to-day clinical work, e.g. to minimize the risk of complications such as perioperative bleeding.
4. Adhesion of the subacromial bursa may cause subacromial impingement in patients with rotator cuff tears: pressure measurements in 18 patients.
Science.gov (United States)
Machida, Akitoshi; Sugamoto, Kazuomi; Miyamoto, Takashi; Inui, Hiroaki; Watanabe, Tetsu; Yoshikawa, Hideki
2004-02-01
In order to determine whether adhesion of the subacromial bursa leads to impingement, we measured the subacromial contact pressures before and after release of adhesion of this bursa. 18 shoulders with cuff tears and adhesion of the subacromial bursa were evaluated in 8 male and 10 female patients, of mean age 62 (53-71) years and who had no particular limitation of shoulder motion. We recorded subacromial pressures using a very sensitive film inserted under the acromion during surgery. In passive scapular plane elevation (scaption) at 100 degrees, the mean subacromial contact pressure and area declined from 1.43 (SD 0.23) MPa before release to 1.14 (SD 0.35) MPa after release (p bursa increases impingement between the acromion and the insertion of rotator cuff tendons.
5. Subacromial osteochondroma: A rare cause of impingement syndrome
OpenAIRE
Çıtlak, Atilla; Akgün, Ulaş; Bulut, Tugrul; Aslan, Cihan; Mete, Berna Dirim; Şener, Muhittin
2014-01-01
Introduction Subacromial impingement syndrome is one of the most common disorders of shoulder. Scapula is a very rare site for osteochondromas, and osteochondromas arising under the acromion cause impingement syndrome. Presentation of case We presented 34-year old female patient with subacromial impingement syndrome secondary to osteochondroma. She had received conservative treatment several times in other clinics. The osteochondroma causing impingement was not diagnosed. Physical examination...
6. Clavicular hook plate may induce subacromial shoulder impingement and rotator cuff lesion--dynamic sonographic evaluation.
Science.gov (United States)
Lin, Hsin-Yu; Wong, Poo-Kuang; Ho, Wei-Pin; Chuang, Tai-Yuan; Liao, Yi-Shyan; Wong, Chin-Chean
2014-02-06
Clavicular hook plates are effective fixation devices for distal clavicle fractures and severe acromioclavicular joint dislocations. However, increasing number of studies has revealed that subacromial portion of the hook may induce acromial bony erosion, shoulder impingement, or even rotator cuff damage. By sonographic evaluation, we thus intended to determine whether the presence of hook plate may induce subacromial shoulder impingement and its relationship relative to surrounding subacromial structures. We prospectively followed 40 patients with either distal clavicle fracture or acromioclavicular joint dislocation that had surgery using the Arbeitsgemeinschaft für Osteosynthesefragen (AO) clavicular hook plate. All patients were evaluated by monthly clinical and radiographic examinations. Static and dynamic musculoskeletal sonography examinations were performed at final follow-up before implant removal. Clinical results for pain, shoulder function, and range of motion were evaluated using Constant-Murley and Disability of Arm, Shoulder, and Hand (DASH) scores. Clinically, 15 out of 40 patients (37.5%) presented with subacromial impingement syndrome and their functional scores were poorer than the non-impinged patients. Among them, six patients were noted to have rotator cuff lesion. Acromial erosion caused by hook pressure developed in 20 patients (50%). We demonstrated by musculoskeletal sonography that clavicular hook plate caused subacromial shoulder impingement and rotator cuff lesion. The data also suggest an association between hardware-induced impingement and poorer functional scores. To our knowledge, the only solution is removal of the implant after bony consolidation/ligamentous healing has taken place. Thus, we advocate the removal of the implant as soon as bony union and/or ligamentous healing is achieved.
7. Clavicular hook plate may induce subacromial shoulder impingement and rotator cuff lesion - dynamic sonographic evaluation
Science.gov (United States)
2014-01-01
Background Clavicular hook plates are effective fixation devices for distal clavicle fractures and severe acromioclavicular joint dislocations. However, increasing number of studies has revealed that subacromial portion of the hook may induce acromial bony erosion, shoulder impingement, or even rotator cuff damage. By sonographic evaluation, we thus intended to determine whether the presence of hook plate may induce subacromial shoulder impingement and its relationship relative to surrounding subacromial structures. Methods We prospectively followed 40 patients with either distal clavicle fracture or acromioclavicular joint dislocation that had surgery using the Arbeitsgemeinschaft für Osteosynthesefragen (AO) clavicular hook plate. All patients were evaluated by monthly clinical and radiographic examinations. Static and dynamic musculoskeletal sonography examinations were performed at final follow-up before implant removal. Clinical results for pain, shoulder function, and range of motion were evaluated using Constant-Murley and Disability of Arm, Shoulder, and Hand (DASH) scores. Results Clinically, 15 out of 40 patients (37.5%) presented with subacromial impingement syndrome and their functional scores were poorer than the non-impinged patients. Among them, six patients were noted to have rotator cuff lesion. Acromial erosion caused by hook pressure developed in 20 patients (50%). Conclusions We demonstrated by musculoskeletal sonography that clavicular hook plate caused subacromial shoulder impingement and rotator cuff lesion. The data also suggest an association between hardware-induced impingement and poorer functional scores. To our knowledge, the only solution is removal of the implant after bony consolidation/ligamentous healing has taken place. Thus, we advocate the removal of the implant as soon as bony union and/or ligamentous healing is achieved. PMID:24502688
8. Detection of subacromial bursa thickening by sonography in shoulder impingement syndrome.
Science.gov (United States)
Tsai, Yao-Hung; Huang, Tsung-Jen; Hsu, Wei-Hsiu; Huang, Kuo-Chin; Li, Yen-Yao; Peng, Kuo-Ti; Hsu, Robert Wen-Wei
2007-01-01
Normally, the subacromial-subdeltoid bursa is thinner than 2 mm using ultrasound examination. The subtle thickening of the bursa could be an early sign of subacromial impingement and possibly a rotator cuff tear. The aim of this study was to compare the thickness of subacromial bursa measured using ultrasonography in the painful shoulder with normal side, and also to differentiate Neer stages I and II impingements in patients with unilateral shoulder pain. We performed bilateral shoulder sonography in 268 consecutive patients with unilateral shoulder pain and clinical suggestion of rotator cuff pathology. The study group consisted of 102 cases of Neer stage I and 166 cases of Neer stage II impingement syndrome. The bursa thickness was calculated from the superficial peribursal fat to the upper margin of the supraspinatus. A statistically significant association was detected (p bursa in patients with Neer stage I impingement had no statistically important link the results of the patients with Neer stage II impingement. Increased bursa thickness in the symptomatic side may be an alternative sonographic indicator of subacromial bursitis and partial-thickness rotator cuff tears, even when measured to be less than 2 mm. Sonographic examination of subacromial bursa thickness is not an appropriate technique to differentiate the Neer stages I and II impingement. Further study is needed to quantify the echogenicity of the supraspinatus tendon and to show a level of accuracy in patients with rotator cuff tendinosis or partial tears.
9. Relation Between Subacromial Bursitis on Ultrasonography and Efficacy of Subacromial Corticosteroid Injection in Rotator Cuff Disease: A Prospective Comparison Study.
Science.gov (United States)
Lee, Doo-Hyung; Hong, Ji Yeon; Lee, Michael Young; Kwack, Kyu-Sung; Yoon, Seung-Hyun
2017-05-01
To evaluate the correlations between subacromial bursitis (bursal thickening and effusion) on ultrasonography and its response to subacromial corticosteroid injection in patients with rotator cuff disease. Prospective, longitudinal comparison study. University-affiliated tertiary care hospital. Patients with rotator cuff disease (N=69) were classified into 3 groups based on ultrasonographic findings; (1) normative bursa group (group 1, n=23): bursa and effusion thickness 2mm and effusion thickness 2mm. A single subacromial injection with 20mg of triamcinolone acetonide. Visual analog scale (VAS) of shoulder pain, Shoulder Disability Questionnaire (SDQ), angles of active shoulder range of motion (flexion, abduction, external rotation, and internal rotation), and bursa and effusion thickness at pre- and posttreatment at week 8. There were no significant differences between the 3 groups in demographic characteristics pretreatment. Groups 2 and 3 showed a significant difference compared with group 1 in changes on the VAS and abduction; group 3 showed a significant difference compared with group 1 in changes of the SDQ, internal rotation, and external rotation; and all groups showed significant differences when compared with each other (groups 1 and 3, 2 and 3, and 1 and 2) in changes of thickness. A patient with ultrasonographic observation of subacromial bursitis, instead of normative bursa, can expect better outcome with subacromial corticosteroid injection. Therefore, we recommend a careful selection of patients using ultrasonography prior to injection. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
10. Physiotherapy improves patient reported shoulder function and health status in patients with subacromial impingement syndrome
DEFF Research Database (Denmark)
Storgaard, Filip Holst; Pedersen, Christina Gravgaard; Jensen, Majbritt Lykke
Physiotherapy improves patient reported shoulder function and health status in patients with subacromial impingement syndrome.......Physiotherapy improves patient reported shoulder function and health status in patients with subacromial impingement syndrome....
11. Ultrasound-Guided Percutaneous Electrolysis and Eccentric Exercises for Subacromial Pain Syndrome: A Randomized Clinical Trial
OpenAIRE
José L. Arias-Buría; Sebastián Truyols-Domínguez; Raquel Valero-Alcaide; Jaime Salom-Moreno; María A. Atín-Arratibel; César Fernández-de-las-Peñas
2015-01-01
Objective. To compare effects of ultrasound- (US-) guided percutaneous electrolysis combined with an eccentric exercise program of the rotator cuff muscles in subacromial pain syndrome. Methods. Thirty-six patients were randomized and assigned into US-guided percutaneous electrolysis (n = 17) group or exercise (n = 19) group. Patients were asked to perform an eccentric exercise program of the rotator cuff muscles twice every day for 4 weeks. Participants assigned to US-guided percutaneous ele...
12. Subacromial impingement syndrome--effectiveness of physiotherapy and manual therapy.
Science.gov (United States)
Gebremariam, Lukas; Hay, Elaine M; van der Sande, Renske; Rinkel, Willem D; Koes, Bart W; Huisstede, Bionka M A
2014-08-01
The subacromial impingement syndrome (SIS) includes the rotator cuff syndrome, tendonitis and bursitis of the shoulder. Treatment includes surgical and non-surgical modalities. Non-surgical treatment is used to reduce pain, to decrease the subacromial inflammation, to heal the compromised rotator cuff and to restore satisfactory function of the shoulder. To select the most appropriate non-surgical intervention and to identify gaps in scientific knowledge, we explored the effectiveness of the interventions used, concentrating on the effectiveness of physiotherapy and manual therapy. The Cochrane Library, PubMed, EMBASE, PEDro and CINAHL were searched for relevant systematic reviews and randomised clinical trials (RCTs). Two reviewers independently extracted data and assessed the methodological quality. A best-evidence synthesis was used to summarise the results. Two reviews and 10 RCTs were included. One RCT studied manual therapy as an add-on therapy to self-training. All other studies studied the effect of physiotherapy: effectiveness of exercise therapy, mobilisation as an add-on therapy to exercises, ultrasound, laser and pulsed electromagnetic field. Moderate evidence was found for the effectiveness of hyperthermia compared to exercise therapy or ultrasound in the short term. Hyperthermia and exercise therapy were more effective in comparison to controls or placebo in the short term (moderate evidence). For the effectiveness of hyperthermia, no midterm or long-term results were studied. In the midterm, exercise therapy gave the best results (moderate evidence) compared to placebo or controls. For other interventions, conflicting, limited or no evidence was found. Some physiotherapeutic treatments seem to be promising (moderate evidence) to treat SIS, but more research is needed before firm conclusions can be drawn. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
13. Conservative or surgical treatment for subacromial impingement syndrome? A systematic review
NARCIS (Netherlands)
Dorrestijn, Oscar; Stevens, Martin; Winters, Jan C.; van der Meer, Klaas; Diercks, Ron L.
2009-01-01
Background: Patients with subacromial impingement syndrome are often operated on when conservative treatments fail. But does surgery really lead to better results than nonoperative measures? This systematic review compared effects of conservative and surgical treatment for subacromial impingement
14. Accuracy of physical examination in subacromial impingement syndrome.
Science.gov (United States)
Silva, L; Andréu, J L; Muñoz, P; Pastrana, M; Millán, I; Sanz, J; Barbadillo, C; Fernández-Castro, M
2008-05-01
Shoulder pain is a common complaint, frequently caused by subacromial impingement syndrome (SIS). There are a number of physical examination (PE) manoeuvres that explore the subacromial space. MRI provides an accurate anatomic image of the subacromial space, being the current gold standard in the diagnosis of SIS. The aim of this study is to evaluate the accuracy of the PE in the diagnosis of SIS and/or subacromial-subdeltoid bursitis (SSB) confirmed by MRI. Consecutive outpatients with an episode of shoulder pain were prospectively included in the study. They were examined by a rheumatologist and, within 3 days, an MRI was done. Sensitivity, specificity, positive and negative predictive values, and accuracy of PE manoeuvres were calculated using a 2 x 2 table. Fourteen males and 16 females were included. All the tests exhibited acceptable sensitivity. As a result Yocum manoeuvre was considered the most sensitive and most accurate for SIS. With regard to SSB, the Gerber test was the most sensitive. The majority of the PE manoeuvres showed low specificity. Most PE manoeuvres identify reasonably well subacromial impingement of the shoulder, although, in general, they have low specificity. The Yocum test has the best sensitivity and precision. Our data suggest that imaging techniques should be recommended to better define shoulder lesions.
15. Increased substance P in subacromial bursa and shoulder pain in rotator cuff diseases.
Science.gov (United States)
Gotoh, M; Hamada, K; Yamakawa, H; Inoue, A; Fukuda, H
1998-09-01
The subacromial bursa is recognized as a site associated with the shoulder pain caused by rotator cuff disease in the middle-aged and elderly. Substance P is contained in primary afferent nerves, and its quantity increases during chronic pain. The amount of substance P in the subacromial bursa of patients with rotator cuff disease was examined. Radioimmunoassay and immunohistochemistry were employed to quantify and localize substance P. The preoperative pain level was measured with a visual analogue scale with 0 as no pain, 5 as moderate, and 10 as severe. Thirty-seven patients that had undergone operation were divided into two groups: one composed of 19 patients with subacromial bursitis and a partial-thickness tear of the rotator cuff (nonperforated cuff) and the other composed of 18 patients with a full-thickness tear (perforated cuff). Subacromial bursae obtained from seven fresh cadavers with no shoulder pain before death were used as controls. The visual analogue scale showed significantly greater pain in the group with the nonperforated rotator cuff than in the group with the perforated cuff. Consistent with these results, the amount of substance P in the subacromial bursa was significantly greater in the former group than in the latter. Nerve fibers immunoreactive to substance P were localized around the vessels, with a larger number of fibers in the group with the nonperforated rotator cuff. Therefore, an increased amount of substance P in the subacromial bursa appears to correlate with the pain caused by rotator cuff disease.
16. Augmented Fixation With Biodegradable Subacromial Spacer After Repair of Massive Rotator Cuff Tear.
Science.gov (United States)
Bozkurt, Murat; Akkaya, Mustafa; Gursoy, Safa; Isik, Cetin
2015-10-01
Unsuccessful outcomes after repair of massive rotator cuff ruptures accompanied by muscle atrophy and fatty degeneration are frequently associated with inadequate management and secondary tears. We report the functional differences after rotator cuff rupture repair with a biodegradable spacer application. In these patients, rotator cuff rupture repair should provide coverage of the humeral head. Subsequently, acromioplasty should be performed to allow adequate space for the subacromial spacer. Thereafter measurement of the intra-articular space required for application of the biodegradable spacer is performed. Using this method can decrease the rate of tears by providing a safe subacromial space in cases of massive rotator cuff rupture.
17. Shoulder proprioception in patients with subacromial impingement syndrome.
Science.gov (United States)
Sahin, Ebru; Dilek, Banu; Baydar, Meltem; Gundogdu, Mehtap; Ergin, Burcu; Manisali, Metin; Akalin, Elif; Gulbahar, Selmin
2017-01-01
Recently, proprioception deficits of the rotator cuff and the deltoid muscles have been suggested to play a pivotal role in the subacromial impingement syndrome (SIS). To date, there are no study has been found where the kinesthesia and joint position senses have been evaluated together in SIS. To investigate the shoulder proprioception in patients with SIS. Sixty-one patients with SIS and 30 healthy controls, aging between 25 and 65 years, were included in the study. Main outcome measure was proprioception, assessed with an isokinetic dynamometer. Kinesthesia, active and passive joint repositioning senses were tested at 0° and 10° external rotation. All tests were repeated 4 times and the mean of angular errors were obtained. The mean age was 49.14 ± 10.27 and 48.80 ± 11.09 years in patient group and in control group respectively. No significant difference was found between two groups in terms of age, gender and dominance. When involved and uninvolved shoulders of the patient group were compared, kinesthesia, active and passive joint position senses were significantly impaired in involved shoulders at all angles (P shoulders of the patient group were compared to the control group, kinesthesia, active and passive joint position senses were significantly impaired in involved shoulders in patient group at all angles (P shoulders of the patient group were compared to the control group, kinesthesia at 10° was significantly impaired (P shoulder proprioception was impaired in patients with SIS. This proprioceptive impairment was found not only in involved shoulders but also in uninvolved shoulders in patients with SIS.
18. Subacromial Anesthetics Increase Proprioceptive Deficit in the Shoulder and Elbow in Patients With Subacromial Impingement Syndrome.
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Ettinger, Lucas R; Shapiro, Matthew; Karduna, Andrew
2017-01-01
Shoulder proprioception gives information regarding arm joint position and movement direction. Several studies have investigated shoulder proprioceptive acuity in patients with subacromial impingement syndrome (SIS); however, differences in protocols and between-subjects designs have limited scientific inferences regarding proprioception and SIS. We aimed to determine within-subject differences in shoulder and elbow proprioceptive acuity in 17 patients with stage 2 SIS following treatment of a local anesthetic injection. In addition, we used 17 healthy, age-, sex-, and arm dominance-matched controls to determine the magnitude of differences after treatment. Joint position sense (JPS) was measured before and after treatment in both groups in the sagittal plane for the shoulder and elbow. Our results indicate that patients with SIS have less sensitivity to angular position and tended to overshoot their targets with greater variability during angle-matching tasks for the shoulder (1.8° difference, P = .042) and elbow (5.6° difference, P = .001) than controls. The disparities in JPS found in patients with SIS were not resolved following subacromial injection; in fact, the magnitude of the errors increased after treatment where postinjection errors were significantly greater (P = .046) than controls, with an average difference of 2.4°. These findings suggest that patients with SIS have decrements in either the signaling or processing of proprioceptive information and may use pain to reduce these inequalities.
19. Subacromial Anesthetics Increase Proprioceptive Deficit in the Shoulder and Elbow in Patients With Subacromial Impingement Syndrome
Directory of Open Access Journals (Sweden)
Lucas R Ettinger
2017-06-01
Full Text Available Shoulder proprioception gives information regarding arm joint position and movement direction. Several studies have investigated shoulder proprioceptive acuity in patients with subacromial impingement syndrome (SIS; however, differences in protocols and between-subjects designs have limited scientific inferences regarding proprioception and SIS. We aimed to determine within-subject differences in shoulder and elbow proprioceptive acuity in 17 patients with stage 2 SIS following treatment of a local anesthetic injection. In addition, we used 17 healthy, age-, sex-, and arm dominance–matched controls to determine the magnitude of differences after treatment. Joint position sense (JPS was measured before and after treatment in both groups in the sagittal plane for the shoulder and elbow. Our results indicate that patients with SIS have less sensitivity to angular position and tended to overshoot their targets with greater variability during angle-matching tasks for the shoulder (1.8° difference, P = .042 and elbow (5.6° difference, P = .001 than controls. The disparities in JPS found in patients with SIS were not resolved following subacromial injection; in fact, the magnitude of the errors increased after treatment where postinjection errors were significantly greater ( P = .046 than controls, with an average difference of 2.4°. These findings suggest that patients with SIS have decrements in either the signaling or processing of proprioceptive information and may use pain to reduce these inequalities.
20. Comparison of subacromial tenoxicam and steroid injections in the treatment of impingement syndrome.
Science.gov (United States)
Çift, Hakan; Özkan, Feyza Ünlü; Tolu, Sena; Şeker, Ali; Mahiroğulları, Mahir
2015-01-01
This study aims to assess and compare the efficacy of subacromial tenoxicam and steroid injections in treating patients with shoulder impingement syndrome. Forty patients having shoulder impingement syndrome with findings of rotator cuff tendinitis or subacromial bursitis on magnetic resonance imaging were included in the study. Patients were randomized into two subacromial injection groups: patients in the first group (10 males, 10 females; mean age 45.3 years; range 32 to 67 years) were administered 20 mg tenoxicam three times by weekly intervals, and patients in the second group (8 males, 12 females; mean age 46.5 years; range 29 to 73 years) were administered 40 mg methylprednisolone acetate just for once. Visual analog scale (VAS), active range of motion (ROM) of the shoulder joint, and Disabilities of Arm, Shoulder and Hand (DASH) questionnaire scores were evaluated at baseline, six weeks after treatment, and first year. Visual analog scale, DASH, and active ROM scores in both groups were statistically significantly improved. No statistically significant difference was detected between subacromial tenoxicam and steroid injections in terms of post-treatment VAS, DASH, and active ROM scores. Mean pre- and post-treatment VAS scores in tenoxicam group were 7.8 (range, 3-9) and 2.6 (range, 2-4), respectively. Mean pre- and post-treatment VAS scores in steroid group were 6.2 (range, 3-10) and 3.6 (range, 0-7), respectively. Mean pre- and post-treatment DASH scores in tenoxicam group were 59.4 (range, 45-80) and 14.7 (range, 8.3-25.8), respectively. Mean pre- and post-treatment DASH scores in steroid group were 56.7 (range, 33.3-85.8) and 18.1 (range, 0-69.2), respectively. Although the improvement in active ROM was higher in the steroid group, difference between two groups was not statistically significant. Both subacromial tenoxicam and steroid injections may be successfully used in the treatment of patients with impingement syndrome. Subacromial tenoxicam
1. Case reports: ossified mass of the rotator cuff tendon in the subacromial bursa.
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Matsumoto, Isshin; Ito, Yoichi; Tomo, Hiroyasu; Nakao, Yoshihiro; Takaoka, Kunio
2005-08-01
Unlike calcification, ossification is infrequent in the rotator cuff. We describe the clinical, radiographic, and pathologic findings in 64-year-old man with an ossified mass arising from a calcified portion of the rotator cuff tendon within the subacromial bursa. Mechanical stress and ischemic events are possible causes of cartilage formation followed by endochondral ossification, producing a mass causing outlet impingement.
2. Effect of subacromial sodium hyaluronate injection on rotator cuff disease: A double-blind placebo-controlled clinical trial.
Science.gov (United States)
2013-01-01
Rotator cuff disease is a common cause of shoulder pain. There are studies about the effectiveness of sodium hyaluronate injection on shoulder and knee pain, but few studies demonstrating the efficacy of sodium hyaluronate ultrasonography guided injection for rotator cuff disease. This study evaluates effectiveness of ultrasonography guided subacromial sodium hyaluronate injection in patients with impingment syndrome without rotator cuff complete tear. This prospective, double-blind, placebo controlled clinical trial study was performed among 40 patients with subacromial impingement syndrome without complete tear of rotator cuff. Patients randomly injected ultrasonography guided in 2 groups: Case group by 20 mg of sodium hyaluronate (Fermathron™) and control group by 0.9% normal saline. Both groups received 3 weekly injections. The pain score (100 mm visual analogue score [VAS]) was evaluated before first injection and one week after each injection. The constant score was evaluated before first and 12 week after last injection. Data was analyzed statistically by Independent t-test. In both groups mean VAS has decreased, but more significantly in case group (P hyaluronate are effective in treating rotator cuff disease without complete tears.
3. A comparison of isometric, isotonic concentric and isotonic eccentric exercises in the physiotherapy management of subacromial pain syndrome/rotator cuff tendinopathy: study protocol for a pilot randomised controlled trial.
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Kinsella, Rita; Cowan, Sallie M; Watson, Lyn; Pizzari, Tania
2017-01-01
Subacromial pain syndrome (SPS) involving rotator cuff tendinopathy is a common cause of shoulder pain and disability. Evidence suggests that structured physiotherapy may be as effective as surgery in this condition with significant improvements demonstrated in trials involving scapular retraining, rotator cuff strengthening and flexibility exercises. Most published programs typically utilise isotonic concentric and/or eccentric strengthening modes. Recently, immediate analgesic effects and muscle strength gains following heavy-load isometric exercises in lower limb tendinopathy conditions have been observed. It is pertinent to ascertain whether such outcomes can be replicated in SPS/rotator cuff tendinopathy. The primary aim of this study is to establish the feasibility of undertaking a full-scale randomised controlled trial (RCT) that compares the effects of isometric, isotonic concentric and isotonic eccentric rotator cuff contractions when used as part of a semi-standardised exercise-based physiotherapy program in patients diagnosed with SPS. The secondary aim is to explore potential trends or treatment effects of the exercise intervention. Thirty-six participants diagnosed with SPS will be randomised to one of three intervention groups and undergo a one-on-one exercise-based physiotherapy intervention, involving scapular and rotator cuff muscle retraining and strengthening. Each group will utilise a different mode of rotator cuff strengthening-isometric, isotonic concentric or isotonic eccentric. Rotator cuff tendon responses to isometric loading are not yet established in the literature; hence, individualised, progressive loading will be used in this pilot study in accordance with symptoms. The intervention will involve two phases: during Phase 1 (weeks 1-6) participants undertake the active group-specific physiotherapy treatment; in Phase 2 (weeks 6-12), they undertake a progressive, but no longer group-specific exercise program. To determine feasibility, an
4. Visual scapular dyskinesis: kinematics and muscle activity alterations in patients with subacromial impingement syndrome.
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Lopes, Andrea Diniz; Timmons, Mark K; Grover, Molly; Ciconelli, Rozana Mesquita; Michener, Lori A
2015-02-01
To characterize scapular kinematics and shoulder muscle activity in patients with subacromial impingement syndrome, with and without visually identified scapular dyskinesis. Cross-sectional study. Laboratory. Participants with subacromial impingement syndrome (N=38) were visually classified using a scapular dyskinesis test with obvious scapular dyskinesis (n=19) or normal scapular motion (n=19). Not applicable. An electromagnetic motion capture system measured 3-dimensional kinematics of the thorax, humerus, and scapula. Simultaneously, surface electromyography was used to measure muscle activity of the upper, middle, and lower trapezius; serratus anterior; and infraspinatus during ascending and descending phases of weighted shoulder flexion. Separate mixed-model analyses of variance for the ascending and descending phases of shoulder flexion compared kinematics and muscle activity between the 2 groups. Shoulder disability was assessed with the Pennsylvania Shoulder Score (Penn). The group with obvious dyskinesis reported 6 points lower on Penn shoulder function (0-60 points), exhibited a main group effect of less scapular external rotation of 2.1° during ascent and 2.5° during descent, and had 12.0% higher upper trapezius muscle activity during ascent in the 30° to 60° interval. Patients with obvious dyskinesis and subacromial impingement syndrome have reduced scapular external rotation and increased upper trapezius muscle activity, along with a greater loss of shoulder function compared with those without dyskinesis. These biomechanical alterations can lead to or be caused by scapular dyskinesis. Future studies should determine if correction of these deficits will eliminate scapular dyskinesis and improve patient-rated shoulder use. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
5. Tendon vascularity in overhead athletes with subacromial pain syndrome and its correlation with the resting subacromial space.
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Tsui, Sammi Sin Mei; Leong, Hio Teng; Leung, Vivian Yee Fong; Ying, Michael; Fu, Siu Ngor
2017-05-01
6. Ultrasound-Guided Percutaneous Electrolysis and Eccentric Exercises for Subacromial Pain Syndrome: A Randomized Clinical Trial
Science.gov (United States)
Arias-Buría, José L.; Truyols-Domínguez, Sebastián; Valero-Alcaide, Raquel; Salom-Moreno, Jaime; Atín-Arratibel, María A.; Fernández-de-las-Peñas, César
2015-01-01
Objective. To compare effects of ultrasound- (US-) guided percutaneous electrolysis combined with an eccentric exercise program of the rotator cuff muscles in subacromial pain syndrome. Methods. Thirty-six patients were randomized and assigned into US-guided percutaneous electrolysis (n = 17) group or exercise (n = 19) group. Patients were asked to perform an eccentric exercise program of the rotator cuff muscles twice every day for 4 weeks. Participants assigned to US-guided percutaneous electrolysis group also received the application of galvanic current through acupuncture needle on each session once a week (total 4 sessions). Shoulder pain (NPRS) and disability (DASH) were assessed at baseline, after 2 sessions, and 1 week after the last session. Results. The ANOVA revealed significant Group∗Time interactions for shoulder pain and disability (all, P electrolysis combined with the eccentric exercises experienced greater improvement than those receiving eccentric exercise alone. Conclusions. US-guided percutaneous electrolysis combined with eccentric exercises resulted in small better outcomes at short term compared to when only eccentric exercises were applied in subacromial pain syndrome. The effect was statistically and clinically significant for shoulder pain but below minimal clinical difference for function. Future studies should investigate the long-term effects and potential placebo effect of this intervention. PMID:26649058
7. Ultrasound-Guided Percutaneous Electrolysis and Eccentric Exercises for Subacromial Pain Syndrome: A Randomized Clinical Trial.
Science.gov (United States)
Arias-Buría, José L; Truyols-Domínguez, Sebastián; Valero-Alcaide, Raquel; Salom-Moreno, Jaime; Atín-Arratibel, María A; Fernández-de-Las-Peñas, César
2015-01-01
Objective. To compare effects of ultrasound- (US-) guided percutaneous electrolysis combined with an eccentric exercise program of the rotator cuff muscles in subacromial pain syndrome. Methods. Thirty-six patients were randomized and assigned into US-guided percutaneous electrolysis (n = 17) group or exercise (n = 19) group. Patients were asked to perform an eccentric exercise program of the rotator cuff muscles twice every day for 4 weeks. Participants assigned to US-guided percutaneous electrolysis group also received the application of galvanic current through acupuncture needle on each session once a week (total 4 sessions). Shoulder pain (NPRS) and disability (DASH) were assessed at baseline, after 2 sessions, and 1 week after the last session. Results. The ANOVA revealed significant Group∗Time interactions for shoulder pain and disability (all, P percutaneous electrolysis combined with the eccentric exercises experienced greater improvement than those receiving eccentric exercise alone. Conclusions. US-guided percutaneous electrolysis combined with eccentric exercises resulted in small better outcomes at short term compared to when only eccentric exercises were applied in subacromial pain syndrome. The effect was statistically and clinically significant for shoulder pain but below minimal clinical difference for function. Future studies should investigate the long-term effects and potential placebo effect of this intervention.
8. Ultrasound-Guided Percutaneous Electrolysis and Eccentric Exercises for Subacromial Pain Syndrome: A Randomized Clinical Trial
Directory of Open Access Journals (Sweden)
José L. Arias-Buría
2015-01-01
Full Text Available Objective. To compare effects of ultrasound- (US- guided percutaneous electrolysis combined with an eccentric exercise program of the rotator cuff muscles in subacromial pain syndrome. Methods. Thirty-six patients were randomized and assigned into US-guided percutaneous electrolysis (n=17 group or exercise (n=19 group. Patients were asked to perform an eccentric exercise program of the rotator cuff muscles twice every day for 4 weeks. Participants assigned to US-guided percutaneous electrolysis group also received the application of galvanic current through acupuncture needle on each session once a week (total 4 sessions. Shoulder pain (NPRS and disability (DASH were assessed at baseline, after 2 sessions, and 1 week after the last session. Results. The ANOVA revealed significant Group∗Time interactions for shoulder pain and disability (all, P<0.01: individuals receiving US-guided percutaneous electrolysis combined with the eccentric exercises experienced greater improvement than those receiving eccentric exercise alone. Conclusions. US-guided percutaneous electrolysis combined with eccentric exercises resulted in small better outcomes at short term compared to when only eccentric exercises were applied in subacromial pain syndrome. The effect was statistically and clinically significant for shoulder pain but below minimal clinical difference for function. Future studies should investigate the long-term effects and potential placebo effect of this intervention.
9. SHOULDER MUSCLE IMBALANCE AND SUBACROMIAL IMPINGEMENT SYNDROME IN OVERHEAD ATHLETES
Science.gov (United States)
2011-01-01
Subacromial impingement is a frequent and painful condition among athletes, particularly those involved in overhead sports such as baseball and swimming. There are generally two types of subacromial impingement: structural and functional. While structural impingement is caused by a physical loss of area in the subacromial space due to bony growth or inflammation, functional impingement is a relative loss of subacromial space secondary to altered scapulohumeral mechanics resulting from glenohumeral instability and muscle imbalance. The purpose of this review is to describe the role of muscle imbalance in subacromial impingement in order to guide sports physical therapy evaluation and interventions. PMID:21655457
10. Synovial chondromatosis of the subacromial bursa causing a bursal-sided rotator cuff tear.
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Neumann, Julie A; Garrigues, Grant E
2015-01-01
Synovial chondromatosis is an uncommon condition, and involvement of the shoulder is even more rare. We report on a 39-year-old female who presented with symptoms, radiographic features, and intraoperative findings consistent with multiple subacromial loose bodies resulting in a partial-thickness, bursal-sided rotator cuff tear of the supraspinatus muscle. She was treated with an arthroscopic removal of loose bodies, complete excision of the subacromial/subdeltoid bursa, acromioplasty, and rotator cuff repair. To our knowledge, this is the first report of arthroscopic treatment for a bursal-sided, partial-thickness rotator cuff tear treated with greater than two-year clinical and radiographic follow-up. We utilized shoulder scores, preoperative and postoperative range of motion, and imaging to assess the results of treatment and surveillance for recurrence in our patient after two-year follow-up.
11. Guideline for diagnosis and treatment of subacromial pain syndrome: a multidisciplinary review by the Dutch Orthopaedic Association.
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Diercks, Ron; Bron, Carel; Dorrestijn, Oscar; Meskers, Carel; Naber, René; de Ruiter, Tjerk; Willems, Jaap; Winters, Jan; van der Woude, Henk Jan
2014-06-01
Treatment of "subacromial impingement syndrome" of the shoulder has changed drastically in the past decade. The anatomical explanation as "impingement" of the rotator cuff is not sufficient to cover the pathology. "Subacromial pain syndrome", SAPS, describes the condition better. A working group formed from a number of Dutch specialist societies, joined by the Dutch Orthopedic Association, has produced a guideline based on the available scientific evidence. This resulted in a new outlook for the treatment of subacromial pain syndrome. The important conclusions and advice from this work are as follows: (1) The diagnosis SAPS can only be made using a combination of clinical tests. (2) SAPS should preferably be treated non-operatively. (3) Acute pain should be treated with analgetics if necessary. (4) Subacromial injection with corticosteroids is indicated for persistent or recurrent symptoms. (5) Diagnostic imaging is useful after 6 weeks of symptoms. Ultrasound examination is the recommended imaging, to exclude a rotator cuff rupture. (6) Occupational interventions are useful when complaints persist for longer than 6 weeks. (7) Exercise therapy should be specific and should be of low intensity and high frequency, combining eccentric training, attention to relaxation and posture, and treatment of myofascial trigger points (including stretching of the muscles) may be considered. (8) Strict immobilization and mobilization techniques are not recommended. (9) Tendinosis calcarea can be treated by shockwave (ESWT) or needling under ultrasound guidance (barbotage). (10) Rehabilitation in a specialized unit can be considered in chronic, treatment resistant SAPS, with pain perpetuating behavior. (11) There is no convincing evidence that surgical treatment for SAPS is more effective than conservature management. (12) There is no indication for the surgical treatment of asymptomatic rotator cuff tears.
12. The Use of Physiotherapy among Patients with Subacromial Impingement Syndrome
DEFF Research Database (Denmark)
Christiansen, David Høyrup; Frost, Poul; Frich, Lars Henrik
2016-01-01
BACKGROUND: Physiotherapy with exercises is generally recommended in the treatment of patients with subacromial impingement syndrome (SIS). OBJECTIVE: We aimed to investigate the use of physiotherapy in patients with SIS in Danish hospital settings as part of initial non-surgical treatment...... and after SIS-related surgery and to evaluate to which extent sex, socio-demographic and clinical factors predict the use of physiotherapy. METHODS: Using national health registers, we identified 57,311 patients who had a first hospital contact with a diagnosis of ICD-10, groups M75.1-75.9, 1 July 2007...... to 30 June 2011. Records of physiotherapy were extracted within 52 weeks after first contact (or until surgery), and for surgically treated patients within 26 weeks after surgery. Predictors of the use of physiotherapy after first contact and after surgery were analysed as time-to-event. RESULTS: Within...
13. Shoulder abduction torque steadiness is preserved in subacromial impingement syndrome.
Science.gov (United States)
Camargo, Paula Rezende; Avila, Mariana Arias; de Oliveira, Ana Beatriz; Asso, Naoe Aline; Benze, Benedito Galvão; de Fátima Salvini, Tania
2009-06-01
This study compared peak torque and torque steadiness during isometric abduction in subjects with subacromial impingement syndrome (SIS) and those with no upper limb disorders. The SIS group consisted of 27 subjects (33.48 +/- 9.94 years) with unilateral SIS. The control group consisted of 23 healthy and active subjects (32.26 +/- 9.04 years). Peak torque and torque steadiness were measured during isometric abduction (80 masculine in the scapular plane) of the shoulder. Standard deviation, coefficient of variation, stability time, median frequency, and relative power were measured from the steadiness trials. There were neither significant interactions between group and side (P > 0.05), nor were there significant main effects of group and side (P > 0.05) for all variables analyzed. The results of this study showed that steadiness is preserved by SIS during isometric abduction of the shoulder.
14. Efficacy of a Subacromial Corticosteroid Injection for Persistent Pain After Arthroscopic Rotator Cuff Repair.
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Shin, Sang-Jin; Do, Nam-Hoon; Lee, Juyeob; Ko, Young-Won
2016-09-01
Corticosteroid injections have been widely used for reducing shoulder pain. However, catastrophic complications induced by corticosteroid such as infections and tendon degeneration have made surgeons hesitant to use a corticosteroid injection as a pain control modality, especially during the postoperative recovery phase. To determine the effectiveness and safety of a subacromial corticosteroid injection for persistent pain control during the recovery period and to analyze the factors causing persistent pain after arthroscopic rotator cuff repair. Cohort study; Level of evidence, 3. A total of 458 patients who underwent arthroscopic rotator cuff repair were included in this study. Patient-specific parameters, tear size and pattern, and pain intensity were reviewed. Seventy-two patients were administered a postoperative subacromial corticosteroid injection under ultrasound guidance. The corticosteroid injection was administered to patients who awakened overnight because of constant severe shoulder pain or whose pain was exacerbated at the time of rehabilitation exercises within 8 weeks after surgery. Pain intensity, patient satisfaction, and functional outcomes using the American Shoulder and Elbow Surgeons (ASES) and Constant scores were compared between the patients with and without a subacromial corticosteroid injection. The retear rate was evaluated with magnetic resonance imaging at 6 months postoperatively. In patients with an injection, the mean (±SD) visual analog scale for pain (pVAS) score was 7.7 ± 1.2 at the time of the injection. This significantly decreased to 2.3 ± 1.4 at the end of the first month after the injection, demonstrating a 70.2% reduction in pain (P rotator cuff tears (41.8%) showed a higher occurrence of severe postoperative persistent pain. Preoperative shoulder stiffness was revealed as a predisposing factor for persistent pain (odds ratio, 0.2; P = .04). A subacromial corticosteroid injection can be considered as a useful and safe
15. Contrast-enhanced MRI of the subdeltoid, subacromial bursa in painful and painless rotator cuff tears
Science.gov (United States)
Hodgson, R J; O'Connor, P J; Hensor, E M A; Barron, D; Robinson, P
2012-01-01
Objective Although shoulder pain is often associated with rotator cuff tears, many tears are asymptomatic and are not the cause of the patient's pain. This may explain the persistence of symptoms in some patients despite technically successful rotator cuff repair. It has been proposed that rotator cuff tears cause pain through subdeltoid/subacromial bursal inflammation. The aim of this study was to determine whether bursal inflammation seen on MRI is associated with pain in patients with rotator cuff tears of the shoulder. Methods The shoulders of 255 patients were screened with ultrasound. 33 full-thickness rotator cuff tears (18 with shoulder pain and 15 without pain) were identified and subsequently studied using contrast-enhanced MRI of the shoulder. Enhancement of the subacromial bursa was scored independently by two musculoskeletal radiologists. Logistic regression was used to determine whether bursal enhancement was independently associated with pain. Results There was a significant association between pain and age, with greater likelihood of pain in younger patients. Bursal enhancement was common in both painful and painless tears. No statistically significant link between pain and bursal enhancement was seen, even after accounting for age. Conclusion Although enhancement of the subdeltoid/subacromial bursa was common, no evidence was found to support the hypothesis that bursal enhancement is associated with pain in rotator cuff tears. It is therefore unlikely to determine reliably which patients would benefit from rotator cuff repair. Advances in knowledge Bursal enhancement and thickening does not reliably correlate with symptoms or presence of rotator cuff tear. PMID:23091289
16. Efficacy of Proprioceptive Exercises in Patients with Subacromial Impingement Syndrome: A Single-Blinded Randomized Controlled Study.
Science.gov (United States)
Dilek, Banu; Gulbahar, Selmin; Gundogdu, Mehtap; Ergin, Burcu; Manisali, Metin; Ozkan, Mustafa; Akalin, Elif
2016-03-01
The objective of this study was to evaluate the effectiveness of proprioceptive exercises on shoulder proprioception, range of motion, pain, muscle strength, and function in patients with subacromial impingement syndrome. Sixty-one patients with subacromial impingement syndrome participated in this prospective, single-blind randomized controlled trial. All patients were randomly divided into two groups: control group (conventional physiotherapy, n = 30) and intervention group (proprioceptive exercise and conventional physiotherapy, n = 31). The primary outcome measures were sense of kinesthesia and active and passive repositioning for proprioception at 0 degrees and 10 degrees external rotation at 12 wks. The secondary outcome measures were pain at rest, at night, and during activities of daily living with the visual analog scale (0-10 cm), the Western Ontario Rotator Cuff index, the American Shoulder and Elbow Surgeons index, range of motion, and isometric muscle strength at both 6 and 12 wks. After treatment, significant improvement was found in range of motion, pain, isometric muscle strength, kinesthesia at 0 degrees external rotation, and functional tests in both groups. The intervention group showed a significant improvement in kinesthesia at 10 degrees external rotation and active and passive repositioning at 10 degrees external rotation. When groups were compared, there were no statistically significant differences in any of the parameters at 12 wks. Although proprioceptive exercises may provide better proprioceptive acuity, no additional positive effect on other clinical parameters was observed.
17. Effect of dynamic humeral centring (DHC) treatment on painful active elevation of the arm in subacromial impingement syndrome. Secondary analysis of data from an RCT.
Science.gov (United States)
Beaudreuil, Johann; Lasbleiz, Sandra; Aout, Mounir; Vicaut, Eric; Yelnik, Alain; Bardin, Thomas; Orcel, Philippe
2015-03-01
The physiotherapy dynamic humeral centring (DHC) aims to prevent subacromial impingement of rotator cuff tendons during elevation of the arm. The objective of the study was to determine whether DHC acts via an effect on subacromial impingement mechanism by assessing its effect on painful elevation of the arm in subacromial impingement syndrome. This is a secondary analysis of results of a randomised controlled trial of the effectiveness of DHC. Sixty-nine patients with subacromial impingement syndrome were prospectively included. Patients and the assessor were blinded to the study hypothesis and treatment, respectively. Patients underwent DHC or non-specific mobilisation as a control for 6 weeks in 15 supervised individual outpatient sessions with home exercises. Outcomes were pain-free range of motion and presence of painful arc of the shoulder, both in active flexion and abduction of the arm at 3 months. At 3 months, pain-free range of motion, both flexion and abduction, was greater in the DHC group than in the mobilisation group. The number of patients with painful arc during flexion was decreased in the DHC group. DHC improves painful active elevation of the arm. We suggest that DHC may act via a specific effect on subacromial impingement mechanism. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
18. Arthroscopic treatment for synovial chondromatosis of the subacromial bursa associated with partial rotator cuff tear.
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Xu, Caiqi; Yang, Xingguang; Zhao, Jinzhong
2015-02-01
Synovial chondromatosis is characterized by benign synovial proliferation that leads to chondral or osteochondral foci formation. In this case report, a right-handed female suffered from progressively worsening pain and limited mobility of forward elevation, abduction and external rotation in her right shoulder. A shoulder arthroscopy was conducted, during which, thickened bursal synovium and several loose bodies were observed, associated with bursal side tear of rotator cuff. A thorough synovectomy, subacromial debridement and acromioplasty were conducted. The pathological findings were consistent with synovial chondromatosis. After systematic rehabilitation, the patient had relief of shoulder pain and full range of motions in 14-months follow-up. Case report, Level IV.
19. Association between kyphosis and subacromial impingement syndrome: LOHAS study.
Science.gov (United States)
Otoshi, Kenichi; Takegami, Misa; Sekiguchi, Miho; Onishi, Yoshihiro; Yamazaki, Shin; Otani, Koji; Shishido, Hiroaki; Kikuchi, Shinichi; Konno, Shinichi
2014-12-01
Kyphosis is a cause of scapular dyskinesis, which can induce various shoulder disorders, including subacromial impingement syndrome (SIS). This study aimed to clarify the impact of kyphosis on SIS with use of cross-sectional data from the Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS). The study enrolled 2144 participants who were older than 40 years and participated in health checkups in 2010. Kyphosis was assessed by the wall-occiput test (WOT) for thoracic kyphosis and the rib-pelvic distance test (RPDT) for lumbar kyphosis. The associations between kyphosis, SIS, and reduction in shoulder elevation (RSE) were investigated. Age- and gender-adjusted logistic regression analysis demonstrated significant association between SIS and WOT (odds ratio, 1.65; 95% confidence interval, 1.02, 2.64; P shoulder elevation induced by the restriction of the thoracic spine extension and scapular dyskinesis. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
20. Arthroscopic repair for subacromial incarceration of a torn rotator cuff
Directory of Open Access Journals (Sweden)
Hiroyuki Nakamizo
2015-07-01
Conclusion: Arthroscopic reduction and repair are applicable for inverted flap tears of the rotator cuff. The findings of the present study indicated that patients with a heel-type acromion in the anteroposterior view of radiographs are at greater risk for inverted flap tears of the rotator cuff.
1. Exercises and Dry Needling for Subacromial Pain Syndrome: A Randomized Parallel-Group Trial.
Science.gov (United States)
Arias-Buría, José L; Fernández-de-Las-Peñas, César; Palacios-Ceña, María; Koppenhaver, Shane L; Salom-Moreno, Jaime
2017-01-01
This randomized clinical trial investigated the effectiveness of exercise versus exercise plus trigger point (TrP) dry needling (TrP-DN) in subacromial pain syndrome. A randomized parallel-group trial, with 1-year follow-up was conducted. Fifty subjects with subacromial pain syndrome were randomly allocated to receive exercise alone or exercise plus TrP-DN. Participants in both groups were asked to perform an exercise program of the rotator cuff muscles twice daily for 5 weeks. Further, patients allocated to the exercise plus TrP-DN group also received dry needling to active TrPs in the muscles reproducing shoulder symptoms during the second and fourth sessions. The primary outcome was pain-related disability assessed using the Disabilities of the Arm, Shoulder, and Hand questionnaire. Secondary outcomes included mean current pain and the worst pain experienced in the shoulder during the previous week. They were assessed at baseline, 1 week, and 3, 6, and 12 months after the end of treatment. Analysis was according to intention to treat with mixed analysis of covariance adjusted for baseline outcomes. At 12 months, 47 patients (94%) completed follow-up. Statistically larger improvements (all, P < .01) in shoulder disability was found for the exercise plus TrP-DN group at all follow-up periods (post: Δ -20.6 [95% confidence interval (CI) -23.8 to -17.4]; 3 months: Δ -23.2 [95% CI -28.3 to -18.1)]; 6 months: Δ -23.6 [95% CI -28.9 to -18.3]; 12 months: Δ -13.9 [95% CI -17.5 to -10.3]). Both groups exhibited similar improvements in shoulder pain outcomes at all follow-up periods. The inclusion of TrP-DN with an exercise program was effective for improving disability in subacromial pain syndrome. No greater improvements in shoulder pain were observed. This study found that the inclusion of 2 sessions of TrP-DN into an exercise program was effective for improving shoulder pain-related disability at short-, medium-, and long-term; however, no greater
2. Increased IL-1beta expression and myofibroblast recruitment in subacromial bursa is associated with rotator cuff lesions with shoulder stiffness.
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Ko, Jih-Yang; Wang, Feng-Sheng; Huang, Hsuan-Ying; Wang, Ching-Jen; Tseng, Shin-Ling; Hsu, Chin
2008-08-01
We evaluated whether proinflammatory cytokine expression and myofibroblast recruitment in subacromial bursa was linked to rotator cuff lesions with shoulder stiffness. We analyzed expressions of IL-1beta, IL-6, and TNF-alpha in subacromial bursa and joint fluid collected from 14 patients with cuff tears with stiffness as a study group (Group I) and 14 patients with rotator cuff tears without shoulder stiffness as a control group (Group II) using real-time RT-PCR, immunohistochemistry, and ELISA. Myofibroblast apoptosis in subacromial bursa was analyzed using terminal deoxynucleotidyl transferase -mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) and alpha-smooth muscle actin immunofluorescence staining. Shoulder function was evaluated using the Constant score. Group I had higher mRNA expression (p bursa and IL-1beta levels in joint fluid were correlated with a preoperative deficit in shoulder motion (p bursa in rotator cuff lesions are linked to shoulder stiffness.
3. Is there evidence in favor of surgical interventions for the subacromial impingement syndrome?
Science.gov (United States)
Tashjian, Robert Z
2013-09-01
To investigate the effectiveness of surgical and postsurgical interventions for the subacromial impingement syndrome (SIS). Using terms including randomized controlled trial (RCT), shoulder impingement syndrome, rotator cuff impingement, and interventions, the Cochrane Library, PubMed, Embase, PEDro, and CINAHL were searched up to February 2009. Relevant systematic reviews and RCTs in any language that included patients with SIS that was not caused by systemic disease or acute trauma; that evaluated surgical or postsurgical treatment for SIS; that reported outcomes of pain, function, or recovery; and that had a follow-up of ≥ 2 weeks, were selected by 2 independent reviewers and confirmed by consensus. Data on the study population, interventions, outcome measures, and length of follow-up (6 months) were extracted. Two reviewers assessed the methods of the RCTs that were included in reviews other than Cochrane reviews and in RCTs published more recently, rating RCTs that met 6 of 12 Furlan criteria as high quality. The effectiveness of the intervention was rated as moderate, limited, or no evidence, depending on the consistency and quality of the evidence. The included studies were 11 RCTs from a Cochrane review, an additional 2 RCTs that reported on the effectiveness of surgery for SIS, and 3 further RCTs that reported on postsurgical interventions. The quality of the studies was generally poor (10/11 RCTs in the Cochrane review had a high risk of bias; and 3 of the additional RCTs were rated moderate to low quality). Arthroscopic or open subacromial decompression compared with physiotherapy or exercise was investigated in 3 trials. No evidence for differences between the treatments in pain, function, or time to recovery was found in the short, medium, or long term. Five comparisons of arthroscopic versus open subacromial decompression showed no differences in pain or shoulder function scores at any follow-up assessment. One study found no difference in short- or
4. Effects of dry needling to the symptomatic versus control shoulder in patients with unilateral subacromial pain syndrome.
Science.gov (United States)
Koppenhaver, Shane; Embry, Robin; Ciccarello, John; Waltrip, Justin; Pike, Rachel; Walker, Michael; Fernández-de-Las-Peñas, Cesar; Croy, Theodore; Flynn, Timothy
2016-12-01
Initial reports suggest that treating myofascial trigger points in the infraspinatus with dry needling may be effective in treating patients with shoulder pain. However, to date, high quality clinical trials and thorough knowledge of the physiologic mechanisms involved is lacking. To examine the effect of dry needling to the infraspinatus muscle on muscle function, nociceptive sensitivity, and shoulder range of motion (ROM) in the symptomatic and asymptomatic shoulders of individuals with unilateral subacromial pain syndrome. Within-subjects controlled trial. Fifty-seven volunteers with unilateral subacromial pain syndrome underwent one session of dry needling to bilateral infraspinatus muscles. Outcome assessments, including ultrasonic measures of infraspinatus muscle thickness, pressure algometry, shoulder internal rotation and horizontal adduction ROM, and questionnaires regarding pain and related disability were taken at baseline, immediately after dry needling, and 3-4 days later. Participants experienced statistically significant and clinically relevant changes in all self-report measures. Pressure pain threshold and ROM significantly increased 3-4 days, but not immediately after dry needling only in the symptomatic shoulder [Pressure pain threshold: 5.1 (2.2, 8.0) N/cm(2), internal rotation ROM: 9.6 (5.0, 14.1) degrees, horizontal adduction ROM: 5.9 (2.5, 9.4) degrees]. No significant changes occurred in resting or contracted infraspinatus muscle thickness in either shoulder. This study found changes in shoulder ROM and pain sensitivity, but not in muscle function, after dry needling to the infraspinatus muscle in participants with unilateral subacromial pain syndrome. These changes generally occurred 3-4 days after dry needling and only in the symptomatic shoulders. Published by Elsevier Ltd.
5. A new interdisciplinary treatment strategy versus usual medical care for the treatment of subacromial impingement syndrome : a randomized controlled trial
NARCIS (Netherlands)
Dorrestijn, Oscar; Stevens, Martin; Diercks, Ron L.; van der Meer, Klaas; Winters, Jan C.
2007-01-01
Background: Subacromial impingement syndrome (SIS) is the most frequently recorded shoulder disorder. When conservative treatment of SIS fails, a subacromial decompression is warranted. However, the best moment of referral for surgery is not well defined. Both early and late referrals have
6. Preoperative conventional magnetic resonance images versus magnetic resonance arthrography of subacromial impingement syndrome
Energy Technology Data Exchange (ETDEWEB)
Ahn, Sang Hyuk; Park, Jung Hwan; Moon, Tae Yong [Pusan National Univ. Yangsan Hospital, Yangsan (Korea, Republic of); Lee, In Sook; Lee, Seung Jun [Pusan National Univ. Hospital, Busan (Korea, Republic of)
2012-09-15
To evaluate the usefulness of conventional magnetic resonance images (MRI) for arthroscopic surgery in subacromial impingement syndrome of the shoulder, as an alternative to MR arthrography with additional T2 fat saturation images (MRA). The preoperative MRI of 77 patients (45 females, 32 males) (52 right, 25 left) and MRA of 34 patients (14 females, 20 males) (24 right, 10 left) with subsequent arthroscopic confirmation of subacromial impingement syndrome were reviewed retrospectively. The lesions requiring arthroscopic surgery were 95 subacromial spurs, 101 subacromial bursitis, and 51 full-thickness and 44 partial thickness tears of the supraspinatus among 111 cases for both studies. A two by two table was constructed in order to calculate the sensitivity and specificity of both studies against arthroscopic outcomes. Also we analyzed the false positive and false negative cases of the full-thickness tears individually. The detection rates of subacromial spur and bursitis and full and partial thickness tears of the supraspinatus were 91%, 94%, 77%, and 65% in MRI and 93%, 100%, 83%, and 77% in MRA respectively. Their specificities were 33%, 33%, 90%, and 76% in MRI and 50%, 75%, 100%, and 71% in MRA respectively. Eleven false negative cases in regards to MRI resulted in Ellman's grade 3 partial thickness tear (72.7%), mild bursitis (63.6%), greater tuberosity erosion (45.5%), and negative fluid signal of the glenohumeral joint (81.8%). Three false positive cases on the MRI were induced from errors with lower window depth and width on the imagings. Two false negative cases on MRA were induced from the adhesion between Ellman's grade 3 rim rent tear and the glenohumeral joint cavity. Conventional MR images could be used to decide the arthroscopic surgery in subacromial impingement syndrome, as an alternative to MR arthrography with additional T2 fat saturation images.
7. Neuromuscular function in patients with Subacromial Impingement Syndrome and clinical assessment of scapular kinematics
DEFF Research Database (Denmark)
Larsen, Camilla Marie
Dansk resuméSubacromial Impingement Syndrom (SIS), som er karakteriseret ved både skuldersmerte ogfunktionsnedsættelse, er en af de hyppigst rapporterede skulderlidelser i primærsektoren. SIS relateres ofte tilen ubalance mellem de skapula-stabiliserende muskler. Indenfor udvalgte specielle popul...
8. Expression of bioactive bone morphogenetic proteins in the subacromial bursa of patients with chronic degeneration of the rotator cuff.
Science.gov (United States)
Neuwirth, Jana; Fuhrmann, Renée A E; Veit, Amanda; Aurich, Matthias; Stonâns, Ilmars; Trommer, Tilo; Hortschansky, Peter; Chubinskaya, Susanna; Mollenhauer, Juergen A
2006-01-01
Degeneration of the rotator cuff is often associated with inflammation of the subacromial bursa and focal mineralization of the supraspinatus tendon. Portions of the supraspinatus tendon distant from the insertion site could transform into fibrous cartilage, causing rotator-cuff tears owing to mechanical instability. Indirect evidence is presented to link this pathology to ectopic production and secretion of bioactive bone morphogenetic proteins (BMPs) from sites within the subacromial bursa. Surgically removed specimens of subacromial bursa tissue from patients with chronic tears of the rotator cuff were analyzed by immunohistochemistry and reverse transcription-PCR. Bioactive BMP was detected in bursa extracts by a bioassay based on induction of alkaline phosphatase in the osteogenic/myogenic cell line C2C12. Topical and differential expression of BMP-2/4 and BMP-7 mRNA and protein was found in bursa tissue. The bioassay of C2C12 cells revealed amounts of active BMP high enough to induce osteogenic cell types, and blocking BMP with specific antibodies or soluble BMP receptors Alk-3 and Alk-6 abolished the inductive properties of the extract. Sufficient information was gathered to explain how ectopic expression of BMP might induce tissue transformation into ectopic bone/cartilage and, therefore, promote structural degeneration of the rotator cuff. Early surgical removal of the subacromial bursa might present an option to interrupt disease progression.
9. Study protocol subacromial impingement syndrome: the identification of pathophysiologic mechanisms (SISTIM)
Science.gov (United States)
2011-01-01
Background The Subacromial Impingement Syndrome (SIS) is the most common diagnosed disorder of the shoulder in primary health care, but its aetiology is unclear. Conservative treatment regimes focus at reduction of subacromial inflammatory reactions or pathologic scapulohumeral motion patterns (intrinsic aetiology). Long-lasting symptoms are often treated with surgery, which is focused at enlarging the subacromial space by resection of the anterior part of the acromion (based on extrinsic aetiology). Despite that acromionplasty is in the top-10 of orthopaedic surgical procedures, there is no consensus on its indications and reported results are variable (successful in 48-90%). We hypothesize that the aetiology of SIS, i.e. an increase in subacromial pressure or decrease of subacromial space, is multi-factorial. SIS can be the consequence of pathologic scapulohumeral motion patterns leading to humerus cranialisation, anatomical variations of the scapula and the humerus (e.g. hooked acromion), a subacromial inflammatory reaction (e.g. due to overuse or micro-trauma), or adjoining pathology (e.g. osteoarthritis in the acromion-clavicular-joint with subacromial osteophytes). We believe patients should be treated according to their predominant etiological mechanism(s). Therefore, the objective of our study is to identify and discriminate etiological mechanisms occurring in SIS patients, in order to develop tailored diagnostic and therapeutic strategies. Methods In this cross-sectional descriptive study, applied clinical and experimental methods to identify intrinsic and extrinsic etiologic mechanisms comprise: MRI-arthrography (eligibility criteria, cuff status, 3D-segmented bony contours); 3D-motion tracking (scapulohumeral rhythm, arm range of motion, dynamic subacromial volume assessment by combining the 3D bony contours and 3D-kinematics); EMG (adductor co-activation) and dynamometry instrumented shoulder radiographs during arm tasks (force and muscle activation
10. Study protocol subacromial impingement syndrome: the identification of pathophysiologic mechanisms (SISTIM
Directory of Open Access Journals (Sweden)
de Witte Pieter
2011-12-01
Full Text Available Abstract Background The Subacromial Impingement Syndrome (SIS is the most common diagnosed disorder of the shoulder in primary health care, but its aetiology is unclear. Conservative treatment regimes focus at reduction of subacromial inflammatory reactions or pathologic scapulohumeral motion patterns (intrinsic aetiology. Long-lasting symptoms are often treated with surgery, which is focused at enlarging the subacromial space by resection of the anterior part of the acromion (based on extrinsic aetiology. Despite that acromionplasty is in the top-10 of orthopaedic surgical procedures, there is no consensus on its indications and reported results are variable (successful in 48-90%. We hypothesize that the aetiology of SIS, i.e. an increase in subacromial pressure or decrease of subacromial space, is multi-factorial. SIS can be the consequence of pathologic scapulohumeral motion patterns leading to humerus cranialisation, anatomical variations of the scapula and the humerus (e.g. hooked acromion, a subacromial inflammatory reaction (e.g. due to overuse or micro-trauma, or adjoining pathology (e.g. osteoarthritis in the acromion-clavicular-joint with subacromial osteophytes. We believe patients should be treated according to their predominant etiological mechanism(s. Therefore, the objective of our study is to identify and discriminate etiological mechanisms occurring in SIS patients, in order to develop tailored diagnostic and therapeutic strategies. Methods In this cross-sectional descriptive study, applied clinical and experimental methods to identify intrinsic and extrinsic etiologic mechanisms comprise: MRI-arthrography (eligibility criteria, cuff status, 3D-segmented bony contours; 3D-motion tracking (scapulohumeral rhythm, arm range of motion, dynamic subacromial volume assessment by combining the 3D bony contours and 3D-kinematics; EMG (adductor co-activation and dynamometry instrumented shoulder radiographs during arm tasks (force and
11. Effects of conservative therapy applied before arthroscopic subacromial decompression on the clinical outcome in patients with stage 2 shoulder impingement syndrome.
Science.gov (United States)
Aydin, Ali; Yildiz, Vahit; Topal, Murat; Tuncer, Kutsi; Köse, Mehmet; Şenocak, Eyüp
2014-01-01
To investigate the effects of conservative therapy applied before arthroscopic subacromial decompression on the clinical outcome in patients with stage 2 shoulder impingement syndrome. Sixty-eight patients having stage 2 shoulder impingement syndrome and treated with arthroscopic subacromial decompression were included in the study. We divided these patients into 2 groups, whereby 32 (47%) patients received conservative therapy before arthroscopic subacromial decompression and 36 (53%) patients did not receive conservative therapy. We compared both groups in terms of the the Constant, UCLA, and VAS scores for shoulder pain before and after arthroscopic subacromial decompression. Constant, UCLA, and VAS scores were statistically significantly improved in both groups after arthroscopic subacromial decompression (P 0.05). Conservative therapy applied in patients with stage 2 shoulder impingement syndrome before arthroscopic subacromial decompression does not have a positive contribution on the clinical outcome after arthroscopic subacromial decompression.
12. The effectiveness of low laser therapy in subacromial impingement syndrome: a randomized placebo controlled double-blind prospective study
Directory of Open Access Journals (Sweden)
Sebnem Koldas Dogan
2010-01-01
Full Text Available OBJECTIVES: Conflicting results were reported about the effectiveness of Low level laser therapy on musculoskeletal disorders. The aim of this study was to investigate the effectiveness of 850-nm gallium arsenide aluminum (Ga-As-Al laser therapy on pain, range of motion and disability in subacromial impingement syndrome. METHODS: A total of 52 patients (33 females and 19 males with a mean age of 53.59±11.34 years with subacromial impingement syndrome were included. The patients were randomly assigned into two groups. Group I (n = 30, laser group received laser therapy (5 joule/cm² at each point over maximum 5-6 painful points for 1 minute. Group II (n = 22, placebo laser group received placebo laser therapy. Initially cold pack (10 minutes was applied to all of the patients. Also patients were given an exercise program including range of motion, stretching and progressive resistive exercises. The therapy program was applied 5 times a week for 14 sessions. Pain severity was assessed by using visual analogue scale. Range of motion was measured by goniometer. Disability was evaluated by using Shoulder Pain and Disability Index. RESULTS: In group I, statistically significant improvements in pain severity, range of motion except internal and external rotation and SPADI scores were observed compared to baseline scores after the therapy (p0.05. CONCLUSIONS: The Low level laser therapy seems to have no superiority over placebo laser therapy in reducing pain severity, range of motion and functional disability.
13. Subacromial impingement syndrome: An electromyographic study of shoulder girdle muscle fatigue.
Science.gov (United States)
Alizadehkhaiyat, Omid; Roebuck, Margaret M; Makki, Ahmed T; Frostick, Simon P
2018-02-01
Muscle fatigue affecting glenohumeral and/or scapular muscles is suggested as one of the contributing factors to the development of subacromial impingement syndrome (SAIS). Nonetheless, the fatigability of shoulder girdle muscles in association with the pathomechanics of SAIS has not been reported. This study aimed to measure and compare fatigue progression within the shoulder girdle musculature of patients and healthy controls. 75 participants including 39 patients (20 females; 19 males) and 36 healthy controls (15 females; 21 males) participated in the study. Study evaluated the progression of muscle fatigue in 15 shoulder girdle muscles by means of surface and fine-wire EMG during submaximal contraction of four distinct movements (abduction, flexion, internal and external rotation). Shoulder strength, subjective pain experience (McGill Pain Questionnaire), and psychological status (Hospital Anxiety and Depression Scale) were also assessed. The results were compared between patient and control groups according to the gender. Despite marked fatigue observed in the majority of muscles particularly during flexion and abduction at 90°, overall results indicated a lower tendency of fatigue progression in the impingement group across the tests (p fatigue progression in the impingement group can be attributed to the presence of fear avoidance and pain-related muscle inhibition, which in turn lead to adaptations in motor programme to reduce muscle recruitment and activation. The significantly higher levels of pain experience and anxiety/depression in the impingement group further support this proposition. Copyright © 2017 Elsevier Ltd. All rights reserved.
14. MR imaging after rotator cuff repair: full-thickness defects and bursitis-like subacromial abnormalities in asymptomatic subjects
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Zanetti, M.; Hodler, J. [Dept. of Radiology, University Hospital Balgrist, Zurich (Switzerland); Jost, B.; Gerber, C. [Dept. of Orthopedic Surgery, University Hospital Balgrist, Zurich (Switzerland)
2000-06-01
Objective. To determine the prevalence and extent of residual defects or retears and bursitis-like subacromial abnormalities on MR images after rotator cuff repair in asymptomatic subjects, and to define the clinical relevance of these findings.Design and patients. Fourteen completely asymptomatic patients and 32 patients with residual symptoms were investigated 27-53 months (mean 39 months) after open transosseous reinsertion of the rotator cuff. Coronal T2-weighted turbo spin-echo and turbo STIR or T2-weighted fat-suppressed MR images were obtained. The prevalence and extent of residual defects or retears of the rotator cuff and bursitis-like subacromial abnormalities were determined.Results. Residual defects or retears were detected in three (21%) and bursitis-like abnormalities in 14 (100%) of the 14 asymptomatic patients. Fifteen (47%) residual defects or retears and 31 (97%) bursitis-like abnormalities were diagnosed in the 32 patients with residual symptoms. The size of the residual defects/retears was significantly smaller in the asymptomatic group (mean 8 mm, range 6-11 mm) than in the symptomatic group (mean 32 mm, range 7-50 mm) (t-test, P=0.001). The extent of the bursitis-like subacromial abnormalities did not significantly differ (t-test, P>0.05) between asymptomatic (mean 28 x 3 mm) and symptomatic patients (mean 32 x 3 mm).Conclusion. Small residual defects or retears (<1 cm) of the rotator cuff are not necessarily associated with clinical symptoms. Subacromial bursitis-like MR abnormalities are almost always seen after rotator cuff repair even in patients without residual complaints. They may persist for several years after rotator cuff repair and appear to be clinically irrelevant. (orig.)
15. Comprehensive impairment-based exercise and manual therapy intervention for patients with subacromial impingement syndrome: a case series.
Science.gov (United States)
Tate, Angela R; McClure, Philip W; Young, Ian A; Salvatori, Renata; Michener, Lori A
2010-08-01
Case series. Few studies have defined the dosage and specific techniques of manual therapy and exercise for rehabilitation for patients with subacromial impingement syndrome. This case series describes a standardized treatment program for subacromial impingement syndrome and the time course and outcomes over a 12-week period. Ten patients (age range, 19-70 years) with subacromial impingement syndrome defined by inclusion and exclusion criteria were treated with a standardized protocol for 10 visits over 6 to 8 weeks. The protocol included a 3-phase progressive strengthening program, manual stretching, thrust and nonthrust manipulation to the shoulder and spine, patient education, activity modification, and a daily home exercise program of stretching and strengthening. Patients completed a history and measures of impairments and functional disability at 2, 4, 6, and 12 weeks. Treatment success was defined as both a 50% improvement on the Disabilities of the Arm, Shoulder, and Hand (DASH) score and a global rating of change of at least "moderately better." At 6 weeks, 6 of 10 patients had a successful (mean +/- SD) DASH outcome score (initial, 33.9 +/- 16.2; 6 weeks, 8.1 +/- 9.2). At 12 weeks, 8 of 10 patients had a successful DASH outcome score (initial, 33.1 +/- 14; 12 weeks, 8.3 +/- 6.4). As a group, the largest improvement was in the first 2 weeks. The most common impairments for all 10 patients were rotator cuff and trapezius muscle weakness (10 of 10 patients), limited shoulder internal rotation motion (8 of 10 patients), and reduced kyphosis of the midthoracic area (7 of 10 patients). A program aimed at strengthening rotator cuff and scapular muscles, with stretching and manual therapy aimed at thoracic spine and the posterior and inferior soft-tissue structures of the glenohumeral joint appeared to be successful in the majority of patients. This case series describes a comprehensive impairment-based treatment which resulted in symptomatic and functional
16. Specific or general exercise strategy for subacromial impingement syndrome-does it matter?
DEFF Research Database (Denmark)
Shire, Alison R; Stæhr, Thor A B; Overby, Jesper B
2017-01-01
strategy. There is however a lack of evidence comparing such exercise strategies to determine which is the most effective in the treatment of subacromial impingement syndrome. The aim of this review is to evaluate whether implementing specific exercise strategies involving resistive exercises are more......, article reference lists and Clinicaltrials.gov were searched. Studies were considered eligible if they included interventions with resistive specific exercises as compared to general resistance exercise. Four reviewers assessed risk of bias and methodological quality guided by Cochrane recommendations...... was SMD −0.19 (95% CI −0.61, 0.22) and SMD 0.30 (95% CI −0.16, 0.76) for function. Conclusions There is insufficient evidence to support or refute the effectiveness of specific resistive exercise strategies in the rehabilitation of subacromial impingement syndrome. More high quality research is needed...
17. MR imaging after rotator cuff repair: full-thickness defects and bursitis-like subacromial abnormalities in asymptomatic subjects.
Science.gov (United States)
Zanetti, M; Jost, B; Hodler, J; Gerber, C
2000-06-01
To determine the prevalence and extent of residual defects or retears and bursitis-like subacromial abnormalities on MR images after rotator cuff repair in asymptomatic subjects, and to define the clinical relevance of these findings. Fourteen completely asymptomatic patients and 32 patients with residual symptoms were investigated 27-53 months (mean 39 months) after open transosseous reinsertion of the rotator cuff. Coronal T2-weighted turbo spin-echo and turbo STIR or T2-weighted fat-suppressed MR images were obtained. The prevalence and extent of residual defects or retears of the rotator cuff and bursitis-like subacromial abnormalities were determined. Residual defects or retears were detected in three (21%) and bursitis-like abnormalities in 14 (100%) of the 14 asymptomatic patients. Fifteen (47%) residual defects or retears and 31 (97%) bursitis-like abnormalities were diagnosed in the 32 patients with residual symptoms. The size of the residual defects/retears was significantly smaller in the asymptomatic group (mean 8 mm, range 6-11 mm) than in the symptomatic group (mean 32 mm, range 7-50 mm) (t-test, P = 0.001). The extent of the bursitis-like subacromial abnormalities did not significantly differ (t-test, P > 0.05) between asymptomatic (mean 28 x 3 mm) and symptomatic patients (mean 32 x 3 mm). Small residual defects or retears (Subacromial bursitis-like MR abnormalities are almost always seen after rotator cuff repair even in patients without residual complaints. They may persist for several years after rotator cuff repair and appear to be clinically irrelevant.
18. The role of tendon and subacromial bursa in rotator cuff tear pain: a clinical and histopathological study.
Science.gov (United States)
Chillemi, Claudio; Petrozza, Vincenzo; Franceschini, Vincenzo; Garro, Luca; Pacchiarotti, Alberto; Porta, Natale; Cirenza, Mirko; Salate Santone, Francesco; Castagna, Alessandro
2016-12-01
To evaluate a possible association of shoulder pain with the clinical features and the histopathological changes occurring in the ruptured tendon and subacromial bursa of patients with rotator cuff tear. One hundred and eighty patients were clinically evaluated with the constant score and the visual analogue pain scale. Radiographs and MRI were performed. The chronology of the rupture, the muscle fatty degeneration according to Goutallier's scale and the tear size were evaluated. For each patient, a biopsy of the supraspinatus tendon and subacromial bursa was performed during arthroscopic rotator cuff tear repair and the specimens were histopathologically analysed. Clinically, the shoulder was more painful in females, in the presence of a chronic cuff lesion and a low Goutallier's grade (P bursa were directly associated with pain (P bursa compared with those in the rotator cuff. Considering that the bursa plays also an essential role during the healing process, this "new" role of the subacromial bursa as pain generator has important repercussions in both pharmacological and surgical treatments of rotator cuff tears. IV.
19. Evaluation of the effectiveness of three physiotherapeutic treatments for subacromial impingement syndrome: a randomised clinical trial.
Science.gov (United States)
Pérez-Merino, L; Casajuana, M C; Bernal, G; Faba, J; Astilleros, A E; González, R; Giralt, M; Romeu, M; Nogués, M R
2016-03-01
To determine whether dexketoprofen administered by phonophoresis or iontophoresis is more effective for the treatment of subacromial impingement syndrome (SIS) than conventional ultrasound therapy. Randomised clinical trial. University hospital. Ninety-nine participants with SIS without a complete tear of the rotator cuff were assigned at random to three intervention groups. Participants received ultrasound (n=32), phonophoresis with dexketoprofen (50mg/session) (n=33) or iontophoresis with dexketoprofen (50mg/session) (n=34). All participants completed 20 treatment sessions plus exercise therapy and cryotherapy. A visual analogue scale (VAS), the Constant-Murley Scale (CMS) and the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire were administered pre-treatment (baseline), post-treatment and 1 month post-treatment. At baseline, there were no differences between the groups. Post-treatment, VAS score improved by -1.2 points and CMS score improved by 8.9 points in the ultrasound group compared with the iontophoresis group [95% confidence interval (CI) -0.2 to -2.2 and 95% CI 17.0 to 0.7, respectively]. CMS score improved by 7.1 points in the phonophoresis group compared with the iontophoresis group (95% CI 14.8 to -0.7). At 1 month post-treatment, no significant differences were detected between the groups. VAS, CMS and DASH scores of all groups improved post-treatment and at 1 month post-treatment. Ultrasound, iontophoresis with dexketoprofen and phonophoresis with dexketoprofen can improve pain, shoulder function, and physical functioning and symptoms in the upper limb in patients with SIS without a complete tear of the rotator cuff. CLINICAL TRIALS. NCT01748188. Copyright © 2015 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.
20. Exercise therapy after ultrasound-guided corticosteroid injections in patients with subacromial pain syndrome
DEFF Research Database (Denmark)
Ellegaard, Karen; Christensen, Robin; Rosager, Sara
2016-01-01
BACKGROUND: Subacromial pain syndrome (SAPS) accounts for around 50 % of all cases of shoulder pain. The most commonly used treatments are glucocorticosteroid (steroid) injections and exercise therapy; however, despite treatment SAPS patients often experience relapse of their symptoms. Therefore...... the clinical effect of combining steroid and exercise therapy is highly relevant to clarify. The aim of this randomized controlled trial was to investigate if exercise therapy added to steroid injection in patients with SAPS will improve the effect of the injection therapy on shoulder pain. METHODS......: In this two-arm randomized trial running over 26 weeks, patients with unilateral shoulder pain (> 4 weeks) and thickened subacromial bursa (> 2 mm on US) were included. At baseline all participants received two steroid injections into the painful shoulder with an interval of one week. Subsequently they were...
1. Subacromial impingement syndrome and pain: protocol for a randomised controlled trial of exercise and corticosteroid injection (the SUPPORT trial).
Science.gov (United States)
Roddy, Edward; Zwierska, Irena; Hay, Elaine M; Jowett, Sue; Lewis, Martyn; Stevenson, Kay; van der Windt, Danielle; Foster, Nadine E
2014-03-14
Subacromial impingement syndrome is the most frequent cause of shoulder problems which themselves affect 1 in 3 adults. Management commonly includes exercise and corticosteroid injection. However, the few existing trials of exercise or corticosteroid injection for subacromial impingement syndrome are mostly small, of poor quality, and focus only on short-term results. Exercise packages tend to be standardised rather than individualised and progressed. There has been much recent interest in improving outcome from corticosteroid injections by using musculoskeletal ultrasound to guide injections. However, there are no high-quality trials comparing ultrasound-guided and blind corticosteroid injection in subacromial impingement syndrome. This trial will investigate how to optimise the outcome of subacromial impingement syndrome from exercise (standardised advice and information leaflet versus physiotherapist-led exercise) and from subacromial corticosteroid injection (blind versus ultrasound-guided), and provide long-term follow-up data on clinical and cost-effectiveness. The study design is a 2x2 factorial randomised controlled trial. 252 adults with subacromial impingement syndrome will be recruited from two musculoskeletal Clinical Assessment and Treatment Services at the primary-secondary care interface in Staffordshire, UK. Participants will be randomised on a 1:1:1:1 basis to one of four treatment groups: (1) ultrasound-guided subacromial corticosteroid injection and a physiotherapist-led exercise programme, (2) ultrasound-guided subacromial corticosteroid injection and an advice and exercise leaflet, (3) blind subacromial corticosteroid injection and a physiotherapist-led exercise programme, or (4) blind subacromial corticosteroid injection and an advice and exercise leaflet. The primary intention-to-treat analysis will be the mean differences in Shoulder Pain and Disability Index (SPADI) scores at 6 weeks for the comparison between injection interventions and at
2. Analyses of possible risk factors for subacromial impingement syndrome
OpenAIRE
Tangtrakulwanich, Boonsin; Kapkird, Anucha
2012-01-01
AIM: To evaluate the association between various risk factors, including sleeping position, and impingement syndrome. Impingement syndrome is the most common cause of shoulder problems. The pathogenesis of this problem is still debated these days.
3. A new interdisciplinary treatment strategy versus usual medical care for the treatment of subacromial impingement syndrome: a randomized controlled trial
Directory of Open Access Journals (Sweden)
van der Meer Klaas
2007-02-01
Full Text Available Abstract Background Subacromial impingement syndrome (SIS is the most frequently recorded shoulder disorder. When conservative treatment of SIS fails, a subacromial decompression is warranted. However, the best moment of referral for surgery is not well defined. Both early and late referrals have disadvantages – unnecessary operations and smaller improvements in shoulder function, respectively. This paper describes the design of a new interdisciplinary treatment strategy for SIS (TRANSIT, which comprises rules to treat SIS in primary care and a well-defined moment of referral for surgery. Methods/Design The effectiveness of an arthroscopic subacromial decompression versus usual medical care will be evaluated in a randomized controlled trial (RCT. Patients are eligible for inclusion when experiencing a recurrence of SIS within one year after a first episode of SIS which was successfully treated with a subacromial corticosteroid injection. After inclusion they will receive injection treatment again by their general practitioner. When, after this treatment, there is a second recurrence within a year post-injection, the participants will be randomized to either an arthroscopic subacromial decompression (intervention group or continuation of usual medical care (control group. The latter will be performed by a general practitioner according to the Dutch National Guidelines for Shoulder Problems. At inclusion, at randomization and three, six and 12 months post-randomization an outcome assessment will take place. The primary outcome measure is the patient-reported Shoulder Disability Questionnaire. The secondary outcome measures include both disease-specific and generic measures, and an economic evaluation. Treatment effects will be compared for all measurement points by using a GLM repeated measures analyses. Discussion The rationale and design of an RCT comparing arthroscopic subacromial decompression with usual medical care for subacromial
4. [Diagnostic value of a predictive model for complete ruptures of the rotator cuff associated to subacromial impingement].
Science.gov (United States)
Águila-Ledesma, I R; Córdova-Fonseca, J L; Medina-Pontaza, O; Núñez-Gómez, D A; Calvache-García, C; Pérez-Atanasio, J M; Torres-González, R
2017-01-01
Pathology related to the rotator cuff remains among the most prevalent musculoskeletal diseases. There is an increasing need for imaging studies (MRI, US, arthroscopy) to test the diagnostic performance of the medical history and physical examination. To prove the diagnostic value of a clinical-radiographic predictive model to find complete ruptures of the rotator cuff. Descriptive, observational, prospective, transversal and analytical study. Fifty-five patients with preoperative shoulder pain were evaluated with 13 predictive variables: age > 50 years, nocturnal pain, muscle weakness, clinical signs of Neer, Hawkins, Jobe, external rotation lag (ERLS), belly-press, bear hug, and lift-off, radiographic measurement of subacromial space, acromial index and critical shoulder angle. Sensitivity, specificity, and positive and negative predictive values were measured in each variable, comparing the results of each one against the postoperative findings. Of the 55 patients evaluated, 42 had a complete rupture of the rotator cuff in the postoperative period. The eight variables with a higher diagnostic value were selected and a ROC curve was performed, providing an area under the curve of 0.88. This predictive model uses eight variables (age > 50 years, nocturnal pain, muscle weakness, Jobe, Hawkins, ERLS, subacromial space ≤ 6 mm, and critical shoulder angle > 35°), which together add the predictive value of 0.88 (AUC) to diagnose complete ruptures of the supraspinatus tendon.
5. Carrageenan-induced subacromial bursitis caused changes in the rat's rotator cuff.
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Tillander, B; Franzén, L E; Nilsson, E; Norlin, R
2001-05-01
This study was designed to investigate the histologic expression of the rat's supra- and infraspinatus tendons in carrageenan-induced subacromial bursitis. Thirty-two rats received subacromial injections with carrageenan (n = 28) or saline (n = 4). The tendons were analysed microscopically after staining with hematoxyline eosin, Van Giesons hematoxyline and immunofluorescent staining of fibronectin and fibrinogen. In the controls (saline x 10) and group A (carrageenan x 5) there were no changes in the tendons. In group B (carrageenan x 10) 3/8 rats showed macrophages between the collagen fibres and an increased staining of fibronectin. In group C (double dosis carrageenan) all rats had signs of fibrocartilaginous metaplasia in the supraspinatus tendon. In eight of these specimens even bony metaplasia was seen. The infraspinatus tendon showed fibrosis but no fibrocartilaginous metaplasia. The results showed that iatrogenic bursitis after carrageenan subacromial injections was associated with marked changes of the supraspinatus tendon.
6. An evidence-based review of current perceptions with regard to the subacromial space in shoulder impingement syndromes: Is it important and what influences it?
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Mackenzie, Tanya Anne; Herrington, Lee; Horlsey, Ian; Cools, Ann
2015-08-01
Reduction of the subacromial space as a mechanism in the etiology of shoulder impingement syndromes is debated. Although a reduction in this space is associated with shoulder impingement syndromes, it is unclear if this observation is cause or consequence. The purposes of this descriptive review are to provide a broad perspective on the current perceptions with regard to the pathology and pathomechanics of subacromial and internal impingement syndromes, consider the role of the subacromial space in impingement syndromes, describe the intrinsic and extrinsic mechanisms considered to influence the subacromial space, and critique the level of evidence supporting these concepts. Based on the current evidence, the hypothesis that a reduction in subacromial space is an extrinsic cause of impingement syndromes is not conclusively established and the evidence permits no conclusion. If maintenance of the subacromial space is important in impingement syndromes regardless of whether it is a cause or consequence, research exploring the correlation between biomechanical factors and the subacromial space, using the later as the outcome measure, would be beneficial. Copyright © 2015 Elsevier Ltd. All rights reserved.
7. Rigid shoulder taping with physiotherapy in patients with subacromial pain syndrome: A randomized controlled trial.
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Apeldoorn, Adri T; Kamper, Steven J; Kalter, Joeri; Knol, Dirk L; van Tulder, Maurits W; Ostelo, Raymond W
2017-04-06
To assess the effectiveness of individualized physiotherapy in combination with rigid taping compared with individualized physiotherapy alone in patients with subacromial pain syndrome. A prospective randomized trial with concealed allocation. A total of 140 patients between 18 and 65 years of age from primary physiotherapy settings. The intervention group received individualized physiotherapy and shoulder taping. The control group received individualized physiotherapy only. Primary outcomes were: pain intensit (numerical rating scale) and functioning (Simple Shoulder Test). Secondary outcomes were: global perceived effect and patient-specific complaints. Data were collected at baseline, and at 4, 12 and 26 weeks' follow-up. During the 6-month follow-up period multilevel analysis showed a significant difference between groups favouring the control group on pain intensity (p = 0.02), but not on functioning. Regarding secondary outcomes, a significant difference between groups was found favouring the intervention group for global perceived effect (p = 0.02), but not for patient-specific complaints. Rigid shoulder taping, as used in this study, cannot be recommended for improving physiotherapy outcomes in people with subacromial pain syndrome.
8. Neuromuscular control of scapula muscles during a voluntary task in subjects with Subacromial Impingement Syndrome
DEFF Research Database (Denmark)
Larsen, C M; Søgaard, Karen; Chreiteh, S S
2013-01-01
Imbalance of neuromuscular activity in the scapula stabilizers in subjects with Subacromial Impingement Syndrome (SIS) is described in restricted tasks and specific populations. Our aim was to compare the scapular muscle activity during a voluntary movement task in a general population with and w......Imbalance of neuromuscular activity in the scapula stabilizers in subjects with Subacromial Impingement Syndrome (SIS) is described in restricted tasks and specific populations. Our aim was to compare the scapular muscle activity during a voluntary movement task in a general population...... with and without SIS (n=16, No-SIS=15). Surface electromyography was measured from Serratus anterior (SA) and Trapezius during bilateral arm elevation (no-load, 1kg, 3kg). Mean relative muscle activity was calculated for SA and the upper (UT) and lower part of trapezius (LWT), in addition to activation ratio...... and time to activity onset. In spite of a tendency to higher activity among SIS 0.10-0.30 between-group differences were not significant neither in ratio of muscle activation 0.80-0.98 nor time to activity onset 0.53-0.98. The hypothesized between-group differences in neuromuscular activity of Trapezius...
9. Effectiveness of Kinesiotaping and Subacromial Corticosteroid Injection in Shoulder Impingement Syndrome.
Science.gov (United States)
Şahin Onat, Şule; Biçer, Seda; Şahin, Zehra; Küçükali Türkyilmaz, Ayşegül; Kara, Murat; Özbudak Demir, Sibel
2016-08-01
The aim of this study was to investigate whether kinesiotaping or subacromial corticosteroid injection provides additional benefit when used with nonsteroidal anti-inflammatory drugs (NSAIDs) in patients with shoulder impingement syndrome. Patients with shoulder impingement syndrome were divided into 3 groups as follows: NSAID group (n = 33), kinesiotaping group (kinesiotaping + NSAID) (n = 33), and injection group (subacromial corticosteroid injection + NSAID) (n = 33). Outcome measures including visual analog scale, shoulder ranges of motion, Shoulder Disability Questionnaire, and University of California-Los Angeles (UCLA) scale were evaluated before and after the treatment (fourth week). A total of 99 patients (21 male and 78 female patients) were enrolled in this study. Demographic and baseline clinical characteristics of the groups (except for body mass index and visual analog scale at night, both P = 0.05) were similar between the groups (all P > 0.05). Clinical parameters were found to have improved in the 3 groups (all P kinesiotaping and injection groups showed similar improvements (all P > 0.05), each group had better outcome than did the NSAID group as regards pain (activity visual analog scale), ranges of motion, and Shoulder Disability Questionnaire and UCLA scale scores (all P kinesiotaping or subacromial corticosteroid injection to NSAID treatment seems to have better/similar effectiveness in patients with shoulder impingement syndrome. Therefore, kinesiotaping might serve as an alternative treatment in case (injection of) corticosteroids are contraindicated. Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME CME OBJECTIVES:: Upon completion of this article, the reader should be able to: (1) Delineate appropriate treatment options for shoulder impingement syndrome; (2) Identify treatment benefits of kinesiotaping and corticosteroid injections in shoulder impingement syndrome; and (3) Incorporate
10. Specific or general exercise strategy for subacromial impingement syndrome-does it matter? A systematic literature review and meta analysis.
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Shire, Alison R; Stæhr, Thor A B; Overby, Jesper B; Bastholm Dahl, Mathias; Sandell Jacobsen, Julie; Høyrup Christiansen, David
2017-04-17
Exercise is frequently suggested as a treatment option for patients presenting with symptoms of subacromial impingement syndrome. Some would argue implementing a specific exercise strategy with special focus on correction of kinematic deficits would be superior to general exercise strategy. There is however a lack of evidence comparing such exercise strategies to determine which is the most effective in the treatment of subacromial impingement syndrome. The aim of this review is to evaluate whether implementing specific exercise strategies involving resistive exercises are more effective than a general exercise strategy for the treatment of patients with subacromial impingement syndrome. Randomized controlled trials were identified through an electronic search on PubMed/MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science and PEDro. In addition, article reference lists and Clinicaltrials.gov were searched. Studies were considered eligible if they included interventions with resistive specific exercises as compared to general resistance exercise. Four reviewers assessed risk of bias and methodological quality guided by Cochrane recommendations. Results were synthesised qualitatively or quantitatively, where appropriate. Six randomized controlled trials were included with 231 participants who experienced symptoms of subacromial impingement syndrome. Four studies evaluated the effectiveness of specific scapular exercise strategy and two studies evaluated the effectiveness of specific proprioceptive strategy. Five studies were of moderate quality and one study was of low quality. No consistent statistical significant differences in outcomes between treatment groups were reported in the studies. Standardized mean difference (SMD) for pain was SMD -0.19 (95% CI -0.61, 0.22) and SMD 0.30 (95% CI -0.16, 0.76) for function. There is insufficient evidence to support or refute the effectiveness of specific resistive exercise strategies in the
11. Force steadiness, muscle activity, and maximal muscle strength in subjects with subacromial impingement syndrome
DEFF Research Database (Denmark)
Bandholm, Thomas; Rasmussen, Lars; Aagaard, Per
2006-01-01
physically active in spite of shoulder pain and nine healthy matched controls were examined to determine isometric and isokinetic submaximal shoulder-abduction force steadiness at target forces corresponding to 20%, 27.5%, and 35% of the maximal shoulder abductor torque, and maximal shoulder muscle strength......We investigated the effects of the subacromial impingement syndrome (SIS) on shoulder sensory-motor control and maximal shoulder muscle strength. It was hypothesized that both would be impaired due to chronic shoulder pain associated with the syndrome. Nine subjects with unilateral SIS who remained...... (MVC). Electromyographic (EMG) activity was assessed using surface and intramuscular recordings from eight shoulder muscles. Force steadiness was impaired in SIS subjects during concentric contractions at the highest target force level only, with muscle activity largely unaffected. No between...
12. Shoulder MRI features with clinical correlations in subacromial pain syndrome: a cross-sectional and prognostic study.
Science.gov (United States)
Kvalvaag, Elisabeth; Anvar, Masoud; Karlberg, Anna Cecilia; Brox, Jens Ivar; Engebretsen, Kaia Beck; Soberg, Helene Lundgaard; Juel, Niels Gunnar; Bautz-Holter, Erik; Sandvik, Leiv; Roe, Cecilie
2017-11-21
Previous studies on shoulder patients have suggested that the prevalence of rotator cuff or bursa abnormalities are weakly related to symptoms and that similar findings are often found in asymptomatic persons. In addition, it is largely unknown whether structural changes identified by magnetic resonance imaging (MRI) affect outcome after treatment for shoulder pain. The purpose of this study was therefore to evaluate the presence of structural changes on MRI in patients with subacromial pain syndrome and to determine to what extent these changes are associated with symptoms and predict outcome after treatment (evaluated by the Shoulder Pain and Disability Index (SPADI)). A prospective, observational assessment of a subset of shoulder patients who were included in a randomized study was performed. All participants had an MRI of the shoulder. An MRI total score for findings at the AC joint, subacromial bursa and rotator cuff was calculated. Multiple linear regression analysis was applied to examine the relationship between the MRI total score and the outcome measure at baseline and to examine to what extent the MRI total score was associated with the change in the SPADI score from baseline to the one year follow-up. There was a weak, inverse association between the SPADI score at baseline and the MRI total score (β = -3.1, with 95% CI -5.9 to -0.34; p = 0.03), i.e. the SPADI score was higher for patients with a lower MRI total score. There was an association between the change in the SPADI score from baseline to the one year follow-up and the MRI total score (β = 8.1, 95% CI -12.3 to -3.8; p bursitis (p = 0.04) were associated with a poorer outcome after one year. In this study, MRI findings were significantly associated with the change in the SPADI score from baseline and to one year follow-up, with a poorer outcome after treatment for the patients with higher MRI total score, tendinosis and bursitis on MRI. Clinicaltrials.gov no NCT01441830
13. Subacromial injection of autologous platelet-rich plasma versus corticosteroid for the treatment of symptomatic partial rotator cuff tears.
Science.gov (United States)
Shams, Ahmed; El-Sayed, Mohamed; Gamal, Osama; Ewes, Waled
2016-12-01
Rotator cuff tears are one of the most common causes of chronic shoulder pain and disability. They significantly affect the quality of life. Reduced pain and improved function are the goals of conventional therapy, which includes relative rest, pain therapy, physical therapy, corticosteroid injections and surgical intervention. Tendons have a relative avascular nature; hence, their regenerative potential is limited. There is some clinical evidence that the application of autologous platelets may help to revascularize the area of injury in rotator cuff pathologies. This prospective randomized controlled study was done to evaluate the results of subacromial injection of platelet-rich plasma (PRP) versus corticosteroid injection therapy in 40 patients with symptomatic partial rotator cuff tears. All patients were assessed before injection, 6 weeks, 3 and 6 months after injection, using the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), the Constant-Murley Score (CMS), the Simple Shoulder Test (SST) and a Visual Analog Scale (VAS) for pain. An MRI was performed before and 6 months after the injection for all the included patients and was graded on 0-5 scale. Both injection groups showed statistically significantly better clinical outcomes over time compared with those before injection. There was a statistically significant difference between RPP group and corticosteroid group 12 weeks after injection, regarding VAS, ASES, CMS and SST in favor of the RPP group. MRI showed an overall slight nonsignificant improvement in grades of tendinopathy/tear in both groups, however, without statistically significant differences between the two groups. PRP injections showed earlier better results as compared to corticosteroid injections, although statistically significant better results after 6 months could not be found. Therefore, subacromial RPP injection could be considered as a good alternative to corticosteroid injection, especially in
14. Neuromuscular function in patients with Subacromial Impingement Syndrome and clinical assessment of scapular kinematics
DEFF Research Database (Denmark)
Larsen, Camilla Marie; Lund, Hans; Juul-Kristensen, Birgit
Neuromuscular function in patients with Subacromial Impingement Syndrome and clinical assessment of scapular kinematics Larsen CM1, Juul-Kristensen B1,2 Holtermann A3, Lund H1,2, Søgaard K1 1University of Southern Denmark, Institute of Sports Science and Clinical Biomechanics, DK 2Institute...... patient sample with SIS, and to assess the clinimetric properties of clinical assessment methods of scapular kinematics as important aspects for optimising effect measures of treatment in order to improve clinical guidelines in this area. METHODS: Scapular muscle activity was examined, 1) during...... a voluntary arm movement task and 2) selective activation tasks during sessions with and without on-line biofeedback, in a general population consisting of 16 SIS patients and 15 controls (No-SIS). Furthermore, 3) a systematic review was conducted of all available clinical scapular assessment methods...
15. Electromyographic activity of the shoulder muscles during rehabilitation exercises in subjects with and without subacromial pain syndrome: a systematic review.
Science.gov (United States)
Kinsella, Rita; Pizzari, Tania
2017-04-01
Subacromial pain syndrome (SPS) is a common cause of shoulder pain and muscle activity deficits are postulated to contribute to the development and progression of the disorder. The purpose of this systematic review was to definitively determine whether evidence exists of differences in electromyography (EMG) characteristics between subjects with and without SPS. Six key databases were searched: MEDLINE, EMBASE, CINAHL, SPORTdiscus, PEDro and The Cochrane Library (inception to May 2016). The search yielded 1414 records using terms relating to shoulder impingement, EMG, scapular and rotator cuff muscles. Twenty-two papers remained once duplicates were removed and selection criteria applied. Data extraction, quality assessment and data synthesis were performed. Effect sizes and 95% confidence intervals were calculated. There was limited evidence that serratus anterior has lower amplitude, delayed activation and earlier termination in SPS participants. For the majority of muscles, regardless of task, load or arm position, significant differences were not demonstrated or results were contradictory. The understanding of SPS is changing and EMG appears unable to capture the complexities associated with this condition. Addressing aberrant movement patterns and facilitating balanced activation of all shoulder muscles may be a more appropriate treatment direction for the future.
16. Taping patients with clinical signs of subacromial impingement syndrome: the design of a randomized controlled trial
Directory of Open Access Journals (Sweden)
Knol Dirk L
2011-08-01
Full Text Available Abstract Background Shoulder problems are a common complaint of the musculoskeletal system. Physical therapists treat these patients with different modalities such as exercise, massage, and shoulder taping. Although different techniques have been described, the effectiveness of taping has not yet been established. The aim of this study is to assess the effectiveness and cost-effectiveness of usual physical therapy care in combination with a particular tape technique for subacromial impingement syndrome of the shoulder compared to usual physical therapy care without this tape technique in a primary healthcare setting. Methods and design An economic evaluation alongside a randomized controlled trial will be conducted. A sample of 140 patients between 18 and 65 years of age with a diagnosis of subacromial impingement syndrome (SAIS as assessed by physical therapists will be recruited. Eligible patients will be randomized to either the intervention group (usual care in combination with the particular tape technique or the control group (usual care without this tape technique. In both groups, usual care will consist of individualized physical therapy care. The primary outcomes will be shoulder-specific function (the Simple Shoulder Test and pain severity (11-point numerical rating scale. The economic evaluation will be performed using a societal perspective. All relevant costs will be registered using cost diaries. Utilities (Quality Adjusted Life Years will be measured using the EuroQol. The data will be collected at baseline, and 4, 12, and 26 weeks follow-up. Discussion This pragmatic study will provide information about the effectiveness and cost-effectiveness of taping in patients presenting with clinical signs of SAIS. Trial registration Trial registration number: NTR2575
17. Finnish Subacromial Impingement Arthroscopy Controlled Trial (FIMPACT): a protocol for a randomised trial comparing arthroscopic subacromial decompression and diagnostic arthroscopy (placebo control), with an exercise therapy control, in the treatment of shoulder impingement syndrome.
Science.gov (United States)
Paavola, Mika; Malmivaara, Antti; Taimela, Simo; Kanto, Kari; Järvinen, Teppo Ln
2017-06-06
Arthroscopic subacromial decompression (ASD) is the most commonly performed surgical intervention for shoulder pain, yet evidence on its efficacy is limited. The rationale for the surgery rests on the tenet that symptom relief is achieved through decompression of the rotator cuff tendon passage. The primary objective of this superiority trial is to compare the efficacy of ASD versus diagnostic arthroscopy (DA) in patients with shoulder impingement syndrome (SIS), where DA differs only by the lack of subacromial decompression. A third group of supervised progressive exercise therapy (ET) will allow for pragmatic assessment of the relative benefits of surgical versus non-operative treatment strategies. Finnish Subacromial Impingement Arthroscopy Controlled Trial is an ongoing multicentre, three-group randomised controlled study. We performed two-fold concealed allocation, first by randomising patients to surgical (ASD or DA) or conservative (ET) treatment in 2:1 ratio and then those allocated to surgery further to ASD or DA in 1:1 ratio. Our two primary outcomes are pain at rest and at arm activity, assessed using visual analogue scale (VAS). We will quantify the treatment effect as the difference between the groups in the change in the VAS scales with the associated 95% CI at 24 months. Our secondary outcomes are functional assessment (Constant score and Simple shoulder test), quality of life (15D and SF-36), patient satisfaction, proportions of responders and non-responders, reoperations/treatment conversions, all at 2 years post-randomisation, as well as adverse effects and complications. We recruited a total of 210 patients from three tertiary referral centres. We will conduct the primary analysis on the intention-to-treat basis. The study was approved by the Institutional Review Board of the Pirkanmaa Hospital District and duly registered at ClinicalTrials.gov. The findings of this study will be disseminated widely through peer-reviewed publications and
18. [Eccentric strength training for the rotator cuff tendinopathies with subacromial impingement. Current evidence].
Science.gov (United States)
Macías-Hernández, Salvador Israel; Pérez-Ramírez, Luis Enrique
2015-01-01
Rotator cuff tears are the leading cause of pain and functional disability of the shoulder. Conservative treatment is an essential part of their management. Despite the limited evidence, rehabilitation is the mainstay of the treatment for rotator cuff tears associated to impingement syndrome. There are current reports on the utility of strengthening with resistance, particularly by eccentric exercise. This report aims to present an overview of the efficacy of eccentric exercises in tendinopathies and current evidence of its benefit in rotator cuff tears. We describe the information available in tendinopathy and analyzed four studies published on eccentric strengthening for rotator cuff tears. There is theoretical evidence about its usefulness in this pathology, but only a controlled clinical trial has been published with data on improvement in strength but not in pain or functionality. More studies are needed with better methodological designs in order to generate evidence of their utility and recommendation. Copyright © 2015. Published by Masson Doyma México S.A.
19. Is exercise effective for the management of subacromial impingement syndrome and other soft tissue injuries of the shoulder? A systematic review by the Ontario Protocol for Traffic Injury Management (OPTIMa) Collaboration.
Science.gov (United States)
Abdulla, Sean Y; Southerst, Danielle; Côté, Pierre; Shearer, Heather M; Sutton, Deborah; Randhawa, Kristi; Varatharajan, Sharanya; Wong, Jessica J; Yu, Hainan; Marchand, Andrée-Anne; Chrobak, Karen; Woitzik, Erin; Shergill, Yaadwinder; Ferguson, Brad; Stupar, Maja; Nordin, Margareta; Jacobs, Craig; Mior, Silvano; Carroll, Linda J; van der Velde, Gabrielle; Taylor-Vaisey, Anne
2015-10-01
20. Physical Therapists' Perceptions and Use of Exercise in the Management of Subacromial Shoulder Impingement Syndrome: Focus Group Study.
Science.gov (United States)
Hanratty, Catherine E; Kerr, Daniel P; Wilson, Iseult M; McCracken, Martin; Sim, Julius; Basford, Jeffrey R; McVeigh, Joseph G
2016-09-01
Shoulder pain resulting from subacromial impingement syndrome (SAIS) is a common problem with a relatively poor response to treatment. There is little research exploring physical therapists' perspectives on the management of the syndrome. The study objective was to investigate physical therapists' perceptions and experiences regarding the use of exercise in the treatment of patients with SAIS. This was a qualitative focus group study. Three 60- to 90-minute focus group sessions containing 6 to 8 experienced musculoskeletal physical therapists (total number=20) were conducted. Thematic content analysis was used to analyze transcripts and develop core themes and categories. Exercise was seen as key in the management of SAIS. The overarching theme was the need to "gain buy-in to exercise" at an early stage. The main subtheme was patient education. Therapists identified the need to use education about SAIS etiology to foster buy-in and "sell" self-management through exercise to the patient. They consistently mentioned achieving education and buy-in using visual tools, postural advice, and sometimes a "quick fix" of pain control. Furthermore, experienced practitioners reported including educational interventions much earlier in treatment than when they first qualified. Therapists emphasized the need for individually tailored exercises, including: scapular stabilization; rotator cuff, lower trapezius, and serratus anterior muscle strengthening; and anterior shoulder and pectoralis minor muscle stretching. Quality of exercise performance was deemed more important than the number of repetitions that the patients performed. Expanding the geographical area over which the focus groups were conducted and including therapists with less than 5 years of postgraduate experience may have strengthened the findings of this study. Experienced musculoskeletal physical therapists believe that exercise is central in treating patients with SAIS and that gaining patient buy-in to its
1. Effects of local microwave diathermy on shoulder pain and function in patients with rotator cuff tendinopathy in comparison to subacromial corticosteroid injections: a single-blind randomized trial.
Science.gov (United States)
Rabini, Alessia; Piazzini, Diana B; Bertolini, Carlo; Deriu, Laura; Saccomanno, Maristella F; Santagada, Domenico A; Sgadari, Antonio; Bernabei, Roberto; Fabbriciani, Carlo; Marzetti, Emanuele; Milano, Giuseppe
2012-04-01
Single-blind randomized clinical trial, with a follow-up of 24 weeks. To determine the effects of hyperthermia via localized microwave diathermy on pain and disability in comparison to subacromial corticosteroid injections in patients with rotator cuff tendinopathy. Hyperthermia improves symptoms and function in several painful musculoskeletal disorders. However, the effects of microwave diathermy in rotator cuff tendinopathy have not yet been established. Ninety-two patients with rotator cuff tendinopathy and pain lasting for at least 3 months were recruited from the outpatient clinic of the Department of Orthopaedics and Traumatology, University Hospital, Rome, Italy. Participants were randomly allocated to either local microwave diathermy or subacromial corticosteroids. The primary outcome measure was the short form of the Disabilities of the Arm, Shoulder and Hand Questionnaire (QuickDASH). Secondary outcome measures were the Constant-Murley shoulder outcome score and a visual analog scale for pain assessment. At the end of treatment and at follow-up, both treatment groups experienced improvements in all outcome measures relative to baseline values. Changes over time in QuickDASH, Constant-Murley, and visual analog scale scores were not different between treatment arms. In patients with rotator cuff tendinopathy, the effects of localized microwave diathermy on disability, shoulder function, and pain are equivalent to those elicited by subacromial corticosteroid injections.
2. Development and delivery of a physiotherapist-led exercise intervention in a randomised controlled trial for subacromial impingement syndrome (the SUPPORT trial).
Science.gov (United States)
Stevenson, Kay; Jackson, Sue; Shufflebotham, Julie; Roddy, Edward; Foster, Nadine E
2017-03-24
This paper describes the development, content and delivery of a physiotherapist- led individualised, supervised and progressed exercise programme for use in a factorial randomised controlled trial testing treatments for subacromial impingement syndrome. To develop the intervention, a survey of community physiotherapists and national guidelines provided the basis for a consensus workshop through which a protocol was developed for the SUPPORT trial physiotherapist-led exercise programme (SUPPORT: SUbacromial impingement syndrome and Pain: a randomised controlled trial Of exeRcise and injection). The protocol included three stages of exercise progression: (1) scapular stability and active exercise with no resistance (2) range of motion exercise with scapular control, isometrics and stretches, and (3) through range resistance exercise. A two day training programme was developed for physiotherapists which included the trial background, current evidence and strategies to improve exercise adherence. Twenty physiotherapists were trained to deliver the exercise intervention. In the SUPPORT trial, 128 participants were randomised to physiotherapist-led exercise. Ninety nine (81%) participants had their first physiotherapy session within 2 to 3 weeks and 71 (56%) received six to eight treatment sessions. Frequently-used exercises were: stage 1 scapular setting with glenohumeral joint (GHJ) flexion to 90°, stage 2 GHJ medial rotation stretch, stage 3 scapular setting through lateral rotation, with resistance bands. We combined clinical and research expertise with national guidance in order to develop a physiotherapist-led, individualised, progressed and supervised exercise intervention for use within a randomised trial. The effectiveness of the intervention is being evaluated within the SUPPORT trial. Trial registration number ISRCTN 42399123. Copyright © 2017 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.
3. Force steadiness, muscle activity, and maximal muscle strength in subjects with subacromial impingement syndrome.
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Bandholm, Thomas; Rasmussen, Lars; Aagaard, Per; Jensen, Bente Rona; Diederichsen, Louise
2006-11-01
We investigated the effects of the subacromial impingement syndrome (SIS) on shoulder sensory-motor control and maximal shoulder muscle strength. It was hypothesized that both would be impaired due to chronic shoulder pain associated with the syndrome. Nine subjects with unilateral SIS who remained physically active in spite of shoulder pain and nine healthy matched controls were examined to determine isometric and isokinetic submaximal shoulder-abduction force steadiness at target forces corresponding to 20%, 27.5%, and 35% of the maximal shoulder abductor torque, and maximal shoulder muscle strength (MVC). Electromyographic (EMG) activity was assessed using surface and intramuscular recordings from eight shoulder muscles. Force steadiness was impaired in SIS subjects during concentric contractions at the highest target force level only, with muscle activity largely unaffected. No between-group differences in shoulder MVC were observed. The present data suggest that shoulder sensory-motor control is only mildly impaired in subjects with SIS who are able to continue with upper body physical activity in spite of shoulder pain. Thus, physical activity should be continued by patients with SIS, if possible, to avoid the loss in neural and muscle functions associated with inactivity.
4. Compressive cryotherapy versus ice-a prospective, randomized study on postoperative pain in patients undergoing arthroscopic rotator cuff repair or subacromial decompression.
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Kraeutler, Matthew J; Reynolds, Kirk A; Long, Cyndi; McCarty, Eric C
2015-06-01
The purpose of this study was to compare the effect of compressive cryotherapy (CC) vs. ice on postoperative pain in patients undergoing shoulder arthroscopy for rotator cuff repair or subacromial decompression. A commercial device was used for postoperative CC. A standard ice wrap (IW) was used for postoperative cryotherapy alone. Patients scheduled for rotator cuff repair or subacromial decompression were consented and randomized to 1 of 2 groups; patients were randomized to use either CC or a standard IW for the first postoperative week. All patients were asked to complete a "diary" each day, which included visual analog scale scores based on average daily pain and worst daily pain as well as total pain medication usage. Pain medications were then converted to a morphine equivalent dosage. Forty-six patients completed the study and were available for analysis; 25 patients were randomized to CC and 21 patients were randomized to standard IW. No significant differences were found in average pain, worst pain, or morphine equivalent dosage on any day. There does not appear to be a significant benefit to use of CC over standard IW in patients undergoing shoulder arthroscopy for rotator cuff repair or subacromial decompression. Further study is needed to determine if CC devices are a cost-effective option for postoperative pain management in this population of patients. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
5. Neuromuscular function in patients with Subacromial Impingement Syndrome and clinical assessment of scapular kinematics
DEFF Research Database (Denmark)
Larsen, Camilla Marie
Neuromuscular function in patients with Subacromial Impingement Syndrome and clinical assessment of scapular kinematics Larsen CM1, Juul-Kristensen B1,2 Holtermann A3, Lund H1,2, Søgaard K1 1University of Southern Denmark, Institute of Sports Science and Clinical Biomechanics, DK 2Institute of Oc...... benefit from biofeedback training. Lastly, these results indicate that very few clinical assessment methods have sufficient clinimetric properties that can be recommended for clinical use....... a voluntary arm movement task and 2) selective activation tasks during sessions with and without on-line biofeedback, in a general population consisting of 16 SIS patients and 15 controls (No-SIS). Furthermore, 3) a systematic review was conducted of all available clinical scapular assessment methods...... parts were below 1.5% activity or (ii) an activation ratio above 95% of the total activity of all muscles, significantly fewer SIS subjects than No-SIS subjects achieved selective activation of individual scapular muscle compartments without on-line biofeedback of muscle activity from each muscle...
6. Topographical pressure pain sensitivity maps of the shoulder region in individuals with subacromial pain syndrome.
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Ribeiro, I L; Camargo, P R; Alburquerque-Sendín, F; Madeleine, P; Fernández-de-las-Peñas, C; Salvini, T F
2016-02-01
Topographical pain maps (TPM) are useful tools to assess deep tissue sensitivity in musculoskeletal pain conditions. There is evidence suggesting bilateral sensitivity in subacromial pain syndrome (SAPS), although it is not widely accepted. No previous study has investigated TPM of the shoulder in SAPS. To investigate whether differences for TPM of the shoulder are evident among patients with unilateral SAPS and controls. Pressure pain thresholds (PPTs) were assessed 3 times at each point and there was a 20 s rest period between each one. The TPM were calculated using 29 pre-determined points on both shoulders in all groups by inverse distance weighted interpolation of PPT data. Multivariate Analysis of Covariance was applied to detect differences in PPTs between groups, sides, points (gender as covariate). The results revealed significant differences between points and genders (both, P shoulder. Women exhibited bilateral lower PPTs in all points than men in both groups (all, P shoulder. Copyright © 2015 Elsevier Ltd. All rights reserved.
7. Effectiveness of individualized physiotherapy on pain and functioning compared to a standard exercise protocol in patients presenting with clinical signs of subacromial impingement syndrome. A randomized controlled trial.
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Kromer, Thilo O; de Bie, Rob A; Bastiaenen, Caroline H G
2010-06-09
Shoulder impingement syndrome is a common musculoskeletal complaint leading to significant reduction of health and disability. Physiotherapy is often the first choice of treatment although its effectiveness is still under debate. Systematic reviews in this field highlight the need for more high quality trials to investigate the effectiveness of physiotherapy interventions in patients with subacromial impingement syndrome. This randomized controlled trial will investigate the effectiveness of individualized physiotherapy in patients presenting with clinical signs and symptoms of subacromial impingement, involving 90 participants aged 18-75. Participants are recruited from outpatient physiotherapy clinics, general practitioners, and orthopaedic surgeons in Germany. Eligible participants will be randomly allocated to either individualized physiotherapy or to a standard exercise protocol using central randomization. The control group will perform the standard exercise protocol aiming to restore muscular deficits in strength, mobility, and coordination of the rotator cuff and the shoulder girdle muscles to unload the subacromial space during active movements. Participants of the intervention group will perform the standard exercise protocol as a home program, and will additionally be treated with individualized physiotherapy based on clinical examination results, and guided by a decision tree. After the intervention phase both groups will continue their home program for another 7 weeks. Outcome will be measured at 5 weeks and at 3 and 12 months after inclusion using the shoulder pain and disability index and patients' global impression of change, the generic patient-specific scale, the average weekly pain score, and patient satisfaction with treatment. Additionally, the fear avoidance beliefs questionnaire, the pain catastrophizing scale, and patients' expectancies of treatment effect are assessed. Participants' adherence to the protocol, use of additional treatments
8. Effectiveness of individualized physiotherapy on pain and functioning compared to a standard exercise protocol in patients presenting with clinical signs of subacromial impingement syndrome. A randomized controlled trial
Directory of Open Access Journals (Sweden)
de Bie Rob A
2010-06-01
Full Text Available Abstract Background Shoulder impingement syndrome is a common musculoskeletal complaint leading to significant reduction of health and disability. Physiotherapy is often the first choice of treatment although its effectiveness is still under debate. Systematic reviews in this field highlight the need for more high quality trials to investigate the effectiveness of physiotherapy interventions in patients with subacromial impingement syndrome. Methods/Design This randomized controlled trial will investigate the effectiveness of individualized physiotherapy in patients presenting with clinical signs and symptoms of subacromial impingement, involving 90 participants aged 18-75. Participants are recruited from outpatient physiotherapy clinics, general practitioners, and orthopaedic surgeons in Germany. Eligible participants will be randomly allocated to either individualized physiotherapy or to a standard exercise protocol using central randomization. The control group will perform the standard exercise protocol aiming to restore muscular deficits in strength, mobility, and coordination of the rotator cuff and the shoulder girdle muscles to unload the subacromial space during active movements. Participants of the intervention group will perform the standard exercise protocol as a home program, and will additionally be treated with individualized physiotherapy based on clinical examination results, and guided by a decision tree. After the intervention phase both groups will continue their home program for another 7 weeks. Outcome will be measured at 5 weeks and at 3 and 12 months after inclusion using the shoulder pain and disability index and patients' global impression of change, the generic patient-specific scale, the average weekly pain score, and patient satisfaction with treatment. Additionally, the fear avoidance beliefs questionnaire, the pain catastrophizing scale, and patients' expectancies of treatment effect are assessed. Participants
9. Cumulative occupational shoulder exposures and surgery for subacromial impingement syndrome: a nationwide Danish cohort study.
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Dalbøge, Annett; Frost, Poul; Andersen, Johan Hviid; Svendsen, Susanne Wulff
2014-11-01
10. Inter- and intrarater reliability of goniometry and hand held dynamometry for patients with subacromial impingement syndrome.
Science.gov (United States)
Fieseler, Georg; Laudner, Kevin G; Irlenbusch, Lars; Meyer, Henrike; Schulze, Stephan; Delank, Karl-Stefan; Hermassi, Souhail; Bartels, Thomas; Schwesig, René
2017-12-01
The purpose of this study was to examine the intra- and interrater reliability of measuring shoulder range of motion (ROM) and strength among patients diagnosed with subacromial impingement syndrome (SAIS). Twenty-five patients (14 female patients; mean age, 60.4± 7.84 years) diagnosed with SAIS were assessed to determine the intrarater reliability for glenohumeral ROM. Twenty-five patients (16 female patients; mean age, 60.4± 7.80 years) and 76 asymptomatic volunteers (52 female volunteers; mean age, 29.4± 14.1 years) were assessed for interrater reliability. Dependent variables were active shoulder ROM and isometric strength. Intrarater reliability was fair-to-excellent for the SAIS patients (intraclass correlation coefficient [ICC], 0.52-0.97; standard error of measurement [SEM], 4.4°-9.9° N; coefficient of variation [CV], 7.1%-44.9%). Based on the ICC, 11 of 12 parameters (92%) displayed an excellent reliability (ICC> 0.75). The interrater reliability showed fair-to-excellent results (SAIS patients: ICC, 0.13-0.98; SEM, 2.3°-8.8°; CV, 3.6%-37.0%; controls: ICC, 0.11-0.96; SEM, 3.0°-35.4°; CV, 5.6%-26.4%). In accordance with the intrarater reliability, glenohumeral adduction ROM was the only parameter with an ICC below 0.75 for both samples. Painful shoulder ROM in the SAIS patients showed no influence on the quality of reliability for measurement. Therefore, these protocols should be considered reliable assessment techniques in the prevention, diagnosis, and treatment of painful shoulder conditions such as SAIS.
11. The Relationship between the Mean Platelet Volume and Subacromial Impingement Syndrome
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Yalkın Çalık
2015-04-01
Full Text Available Objective: Subacromial impingement syndrome (SIS characterized by inflammation of supraspinatus tendon is one of the most common causes of the shoulder pain. In some studies, platelet activity has been shown as a marker to indicate the inflammation associated with the disease. The mean platelet volume (MPV shows platelet function and activation. The aim of this study was to investigate the relationship between MPV and SIS. Materials and Methods: Eighty seven inpatients (female/male: 55/32, mean age: 56.34±7.53 years diagnosed with SIS according to physical examination and MR findings in Bolu Physical Therapy and Rehabilitation Hospital between January 2014- June 2014 constituted the case group, 87 outpatients (female/male 61/26, mean age: 52.97±8.48 years not diagnosed with SIS constituted the control group. MPV values between case and control group that were similar in terms of age and gender were compared. Results: In case group MPV (8.36±0.73*** was lower than that of the control group (8.44±1.02**** and platelet count (253.75±50.17*** was higher than that of the control group (244.79±56.19***. Both were not statistically significant (p>0.05. Significant negative correlation was found between MPV and platelet level in case group (r=-0.240, p<0.05. Conclusion: These findings present that there is no relationship between MPV and SIS. New prospective studies are needed on this subject. (Turkish Journal of Osteoporosis 2015;21: 15-8
12. Single-lead percutaneous peripheral nerve stimulation for the treatment of shoulder pain from subacromial impingement syndrome.
Science.gov (United States)
Wilson, Richard D; Harris, Michael A; Bennett, Maria E; Chae, John
2012-08-01
13. Effects of Low-Load Exercise on Post-needling Induced Pain After Dry Needling of Active Trigger Point in Individuals with Subacromial Pain Syndrome.
OpenAIRE
Salom Moreno, Jaime; Jiménez Gómez, Laura; Gómez Ahufinger, Victoria; Palacios Ceña, María; Arias Buría, José Luis; Koppenhaver, Shane L.; Fernández de las Peñas, César
2017-01-01
Background: Application of dry needling is usually associated to post-needling induced pain. Development of post-needling intervention targeting to reduce this adverse event is needed. Objective: To determine the effectiveness of low-load exercise on reducing post-needling induced-pain after dry needling of active trigger points (TrPs) in the infraspinatus muscle in subacromial pain syndrome.
14. Clinical effectiveness of botulinum toxin type B in the treatment of subacromial bursitis or shoulder impingement syndrome.
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Lee, Jung Hwan; Lee, Sang-Ho; Song, Sun Hong
2011-01-01
Subacromial steroid injections are used as a treatment method in subacromial bursitis (SB) or shoulder impingement syndrome (SIS). However, the steroid effect is relatively restricted to the short-term and repeated injections are frequently required, which contributes to unwanted side effects. As an alternative, botulinum toxin (BT) has recently been used for pain relief. This study aimed to investigate the clinical effectiveness of BT type B and to compare this with the effectiveness of steroids. Sixty-one patients diagnosed with SB or SIS were divided into 2 groups and treated with BT type B (BT group) and trimacinolone injection (TA group) under ultrasound guidance, respectively. Numeric Rating Scale (NRS), active shoulder abduction angle, and the Korean version of the score on the Disability of Arm, Shoulder, and Hand (DASH) were measured before the treatment, and at 1 and 3 months after the treatment. Both groups obtained a significant improvement of NRS, DASH, and active shoulder abduction at 1 and 3 months follow-up. BT group showed significantly better outcomes in terms of reduction of NRS and DASH at 3 months than TA group. BT group showed strong trend toward the larger degree of active shoulder abduction than the TA group at 3 months follow-up, as well. Whereas, no significant difference was found in NRS, DASH, and active shoulder abduction between the 2 groups at 1 month follow-up. BT type B can be a useful strategy and has great potential for replacing steroids as a treatment for SB or SIS.
15. Shouldering the blame for impingement: the rotator cuff continuum ...
African Journals Online (AJOL)
... research on shoulder impingement and rotator cuff pathology. A continuum model of rotator cuff pathology is described, and the challenges of accurate clinical diagnosis, imaging and best management discussed. Keywords: shoulder impingement syndrome, subacromial impingement syndrome, rotator cuff, tendinopathy, ...
16. Kinesiology taping does not alter shoulder strength, shoulder proprioception, or scapular kinematics in healthy, physically active subjects and subjects with Subacromial Impingement Syndrome.
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Keenan, Karen A; Akins, Jonathan S; Varnell, Michelle; Abt, John; Lovalekar, Mita; Lephart, Scott; Sell, Timothy C
2017-03-01
To examine the effect of kinesiology tape (KT) on shoulder strength, proprioception, and scapular kinematics in healthy and Subacromial Impingement Syndrome (SAIS) subjects. Placebo-controlled quasi-experimental study. Research laboratory. A total of 30 physically active subjects participated. Ten healthy subjects with no previous history of shoulder pathology received KT on the dominant shoulder. Twenty subjects with shoulder pain for a minimum of two weeks and presenting with clinical signs of impingement were allotted to receive KT (n = 10) or placebo taping (PT, n = 10) on the involved shoulder. All participants were tested pre- and post-application. Shoulder internal/external rotation (IR/ER) strength was assessed with isokinetic dynamometry (average peak torque/body weight). Shoulder IR/ER proprioception was assessed through threshold to detect passive motion (mean absolute error in degrees). Scapular position at 90° and 120° of shoulder abduction during arm raising/lowering were assessed using a 3D motion analysis system. No significant within group or between group differences were demonstrated for any measure. Taping does not appear to aid/impair shoulder strength, shoulder proprioception, or scapular kinematics. Future research should explore if the effects of KT are time-dependent and similar in other pathologies. Copyright © 2016 Elsevier Ltd. All rights reserved.
17. Short-term effects of high-intensity laser therapy, manual therapy, and Kinesio taping in patients with subacromial impingement syndrome.
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Pekyavas, Nihan Ozunlu; Baltaci, Gul
2016-08-01
Subacromial impingement syndrome (SAIS) is a major contributing factor of shoulder pain; and treatment approaches (Kinesio® taping [KT], Exercise [EX], manual therapy [MT], and high-intensity laser therapy [HILT]) have been developed to treat the pain. The key objective of this study was to compare the effects of KT, MT, and HILT on the pain, the range of motion (ROM), and the functioning in patients with SAIS. Seventy patients with SAIS were randomly divided into four groups based on the treatment(s) each group received [EX (n = 15), KT + EX (n = 20), MT + KT + EX (n = 16), and MT + KT + HILT + EX (n = 19)]. All the patients were assessed before and at the end of the treatment (15th day). The main outcome assessments included the evaluation of severity of pain by visual analogue scale (VAS) and shoulder flexion, abduction, and external rotation ROM measurements by a universal goniometry. Shoulder pain and disability index (SPADI) was used to measure pain and disability associated with shoulder pathology. Statistically significant differences were found in the treatment results of all parameters in MT + KT + EX and HILT + MT + KT + EX groups (p effective in minimizing pain and disability and increasing ROM in patients with SAIS. Further studies with follow-up periods are required to determine the advantages of these treatments conclusively.
18. Effects of weighted and un-weighted pendulum exercises on ultrasonographic acromiohumeral distance in patients with subacromial impingement syndrome.
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Akkaya, Nuray; Akkaya, Semih; Gungor, Harun R; Yaşar, Gokce; Atalay, Nilgun Simsir; Sahin, Fusun
2017-01-01
Although functional results of combined rehabilitation programs are reported, there have been no reports studying the effects of solo pendulum exercises on ultrasonographic measurements of acromiohumeral distance (AHD). To investigate the effects of weighted and un-weighted pendulum exercises on ultrasonographic AHD and clinical symptoms in patients with subacromial impingement syndrome. Patients with subacromial impingement syndrome were randomized to performing weighted (1.5 kilograms hand held dumbbell, N= 18) or un-weighted (free of weight, N= 16) pendulum exercises for 4 weeks, 3 sessions/day. Exercises were repeated for each direction of shoulder motion in each session (ten minutes). Clinical situation was evaluated by Constant score and Shoulder Pain Disability Index (SPADI). Ultrasonographic measurements of AHD at 0°, 30° and 60° shoulder abduction were performed. All clinical and ultrasonographic evaluations were performed at the beginning of the exercise program and at end of 4 weeks of exercise program. Thirty-four patients (23 females, 11 males; mean age 41.7 ± 8.9 years) were evaluated. Significant clinical improvements were detected in both exercise groups between pre and post-treatment evaluations (p shoulder abduction between groups (p > 0.05). There was no significant difference for pre and post-treatment narrowing of AHD (narrowing of 0°-30°, and 0°-60°) between groups (p > 0.05). While significant clinical improvements were achieved with both weighted and un-weighted solo pendulum exercises, no significant difference was detected for ultrasonographic AHD measurements between exercise groups.
19. Physiotherapy after subacromial decompression surgery
DEFF Research Database (Denmark)
Christiansen, David Høyrup; Falla, Deborah; Frost, Poul
2015-01-01
This paper describes the development and details of a standardised physiotherapy exercise intervention designed to address pain and disability in patients with difficulty returning to usual activities after arthroscopic decompression surgery for subacromial impingement syndrome. To develop the in...... is currently being evaluated within the framework of the Shoulder Intervention Project (ISRCTN55768749).......This paper describes the development and details of a standardised physiotherapy exercise intervention designed to address pain and disability in patients with difficulty returning to usual activities after arthroscopic decompression surgery for subacromial impingement syndrome. To develop...
20. Inter-examiner reproducibility of clinical tests and criteria to identify subacromial impingement syndrome
DEFF Research Database (Denmark)
Vind, Mikkel; Bogh, Søren Bie; Larsen, Camilla Marie
2011-01-01
Abstract Introduction A specific algorithm has been proposed for classifying impingement related shoulder pain in athletes with overhead activity. Data on the inter-examiner reproducibility of the suggested clinical tests and criteria and their mutual dependencies for identifying subacromial...... was followed, consisting of a training, an overall agreement and a study phase. To proceed to the study phase, an overall agreement of 0.80 was required. In total 10, 20 and 44 subjects were included in the three phases, respectively. The case prevalence in the study phase was 50%. The inclusion criterion...... reproducibility in clinical practice, as well as the validity of the tests and criteria for SIS....
1. Surgical treatment of the impingement syndrome and of the rotator cuff tears: personal experience in 134 cases
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A. Rioda
2011-09-01
Full Text Available The time-course covered by the original definition of scapulo-humeral periarthritis suggested by Duplay through the more recent term of subacromial impingement syndrome coined by Neer, follows the identification of the pathogenetic mechanisms leading to chronic subacromial impingement and degenerative tears of the rotator cuff. The Authors recall the functional-anatomic development evolution of the shoulder and the disequilibrium between the depressor and the elevator muscles which may promote the chronic friction against the acromion. However, the actual pathogenesis of the impingement still remains controversial. We evaluated 134 patients (81F, 53M, mean age 56.4 years with chronic subacromial impingement syndrome. In 92 cases (69% non traumatic tears of the rotator cuff were also present as confirmed by ultrasonography in 94 cases, CT in18 cases and magnetic resonance in 102 cases. The different tear patterns of the rotator cuff were classified as suggested by Ellman (L shaped, L reverse, triangular, trapezoidal and massive with retraction and clinical results were analysed following Sahlstrand clinical criteria and Costant numerical scale. According to the anatomical damage, patients were divided into those with impingement without severe cuff tendinopathy (42 cases, those with rotator cuff tears without loss of motion of the shoulder (32 cases and those with cuff tears and loss of active motion (60 cases. The different surgical techniques and rehabilitation procedures after surgery are also reported. After a mean follow-up of 1.3 years (range 8 months - 2 years, good or excellent results were obtained in 91% of the patients without rotator cuff tears, in 87% of the patients with tears but without loss of motion and in 75% of the cases with loss of active motion. Our data demonstrate that in the majority of patients with chronic impingement syndrome and rotator cuff tears, surgical treatment shows high success rates. When surgery is
2. Effects of Proprioceptive Neuromuscular Facilitation and Mulligan Concepts on the Pain, Functional Level and Quality of Life on Subacromial Impingement Syndrome
OpenAIRE
Karaku?, Sinem; Gelecek, Nihal; Ye?ilyaprak, Sevgi Sevi
2014-01-01
Objectives: The purpose of the study was to investigate the effects of Proprioceptif Neuromuscular Facilitation (PNF) and Mulligan concepts on the pain, functional level and quality of life in the patients with subacromial impingement syndrome (SIS). Methods: This study was carried out on 40 patients (26 females, 14 males), mean age 50,3?1,13 years, who had been diagnosed as SIS admitted to the physical therapy and rehabilitation clinic. Before the beginning measurements all the patients were...
3. Pathological Fracture of Clavicle Following Sub-Acromial Decompression-Infraclavicular Compartment Syndrome?
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2009-11-01
Full Text Available A 34-year-old factory worker presented with pain and weakness of the left shoulder following a fall on ice on her left shoulder. An ultrasound scan of the shoulder taken 4 months after injury showed small partial articular surface tear of the supraspinatus tendon. Ten days following subacromial decompression she suffered a pathological fracture of her left clavicle. MRI, CT, and isotope bone scans showed no evidence of malignancy or infection but a collection of fluid was noted underlying the clavicle communicating to the acromioclavicular joint. Ultrasound scan guided aspiration of 20 millilitres of bloodstained fluid underlying the clavicle resulted in gradual recovery and adequate healing of the fracture.
4. Arthroscopic subacromial decompression is effective in selected patients with shoulder impingement syndrome.
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Magaji, S A; Singh, H P; Pandey, R K
2012-08-01
A total of 92 patients with symptoms for over six months due to subacromial impingement of the shoulder, who were being treated with physiotherapy, were included in this study. While continuing with physiotherapy they waited a further six months for surgery. They were divided into three groups based on the following four clinical and radiological criteria: temporary benefit following steroid injection, pain in the mid-arc of abduction, a consistently positive Hawkins test and radiological evidence of impingement. Group A fulfilled all four criteria, group B three criteria and group C two criteria. A total of nine patients improved while waiting for surgery and were excluded, leaving 83 who underwent arthroscopic subacromial decompression (SAD). The new Oxford shoulder score was recorded pre-operatively and at three and 12 months post-operatively. A total of 51 patients (group A) had a significant improvement in the mean shoulder score from 18 (13 to 22) pre-operatively to 38 (35 to 42) at three months (p < 0.001). The mean score in this group was significantly better than in group B (21 patients) and C (11 patients) at this time. At one year patients in all groups showed improvement in scores, but patients in group A had a higher mean score (p = 0.01). At one year patients in groups A and B did better than those in group C (p = 0.01). Arthroscopic SAD is a beneficial intervention in selected patients. The four criteria could help identify patients in whom it is likely to be most effective.
5. The clinical and sonographic effects of kinesiotaping and exercise in comparison with manual therapy and exercise for patients with subacromial impingement syndrome: a preliminary trial.
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Kaya, Derya Ozer; Baltaci, Gul; Toprak, Ugur; Atay, Ahmet Ozgur
2014-01-01
The purpose of this study was to compare the effects of manual therapy with exercise to kinesiotaping with exercise for patients with subacromial impingement syndrome. Randomized clinical before and after trial was used. Fifty-four patients diagnosed as having subacromial impingement syndrome who were referred for outpatient treatment were included. Eligible patients (between 30 and 60 years old, with unilateral shoulder pain) were randomly allocated to 2 study groups: kinesiotaping with exercise (n = 28) or manual therapy with exercise (n = 26). In addition, patients were advised to use cold packs 5 times per day to control for pain. Visual analog scale for pain, Disability of Arm and Shoulder Questionnaire for function, and diagnostic ultrasound assessment for supraspinatus tendon thickness were used as main outcome measures. Assessments were applied at the baseline and after completing 6 weeks of related interventions. At the baseline, there was no difference between the 2 group characteristics (P > .05). There were significant differences in both groups before and after treatment in terms of pain decrease and improvement of Disability of Arm and Shoulder Questionnaire scores (P .05). The only difference between the groups was at night pain, resulting in favor of the kinesiotaping with exercise group (P < .05). For the group of subjects studied, no differences were found between kinesiotaping with exercise and manual therapy with exercise. Both treatments may have similar results in reducing pain and disability in subacromial impingement in 6 weeks. Copyright © 2014 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.
6. The impact of subacromial impingement syndrome on muscle activity patterns of the shoulder complex: a systematic review of electromyographic studies
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Smith Toby O
2010-03-01
Full Text Available Abstract Background Subacromial impingement syndrome (SIS is a commonly reported cause of shoulder pain. The purpose of this study was to systematically review the literature to examine whether a difference in electromyographic (EMG activity of the shoulder complex exists between people with SIS and healthy controls. Methods Medline, CINAHL, AMED, EMBASE, and grey literature databases were searched from their inception to November 2008. Inclusion, data extraction and trial quality were assessed in duplicate. Results Nine studies documented in eleven papers, eight comparing EMG intensity and three comparing EMG onset timing, representing 141 people with SIS and 138 controls were included. Between one and five studies investigated each muscle totalling between 20 and 182 participants. The two highest quality studies of five report a significant increase in EMG intensity in upper trapezius during scaption in subjects with SIS. There was evidence from 2 studies of a delayed activation of lower trapezius in patients with SIS. There was otherwise no evidence of a consistent difference in EMG activity between the shoulders of subjects with painful SIS and healthy controls. Conclusions A difference may exist in EMG activity within some muscles, in particular upper and lower trapezius, between people with SIS and healthy controls. These muscles may be targets for clinical interventions aiding rehabilitation for people with SIS. These differences should be investigated in a larger, high quality survey and the effects of therapeutically targeting these muscles in a randomised controlled trial.
7. Predicting Response to Subacromial Injections and Lidocaine/Tetracaine Patch from Pretreatment Pain Quality in Patients with Shoulder Impingement Syndrome.
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Gammaitoni, Arnold R; Trudeau, Jeremiah J; Radnovich, Richard; Galer, Bradley S; Jensen, Mark P
2015-07-01
No existing pain treatment is effective for all pain problems, and response to pain treatment is highly variable. Knowledge regarding the patient factors that predict response to different treatments could benefit patients by providing an empirical foundation for patient-treatment matching. This study sought to test the hypothesis that improvements following two treatments thought to operate via similar mechanisms would be predicted by similar baseline pain qualities. Prospective prediction analysis using data from a previously published open label trial comparing a heated lidocaine/tetracaine patch versus subacromial corticosteroid injection for the treatment of pain in individuals with shoulder impingement syndrome. Consistent with the study hypothesis, the response to the two treatments were predicted by similar baseline pain qualities; specifically, higher baseline levels of unpleasant, electric, and sensitive pain predicted subsequent improvements in sleep interference, work/activity interference, and patient global ratings of improvement, respectively. The findings are consistent with the combined ideas that (1) those who have the most to gain (i.e., those reporting the highest levels of various pain qualities) can expect the best response to effective treatments and (2) different pain qualities may be associated with different types of outcomes. The findings support further research to examine how pain quality measures may be used to improve patient-treatment matching, and therefore, ultimately improve the efficiency, efficacy, and overall benefit-risk of pain treatment. Wiley Periodicals, Inc.
8. Kinesio taping or just taping in shoulder subacromial impingement syndrome? A randomized, double-blind, placebo-controlled trial.
Science.gov (United States)
Kocyigit, Figen; Acar, Merve; Turkmen, Mehmet Besir; Kose, Tugce; Guldane, Nezahat; Kuyucu, Ersin
2016-10-01
To verify effects of kinesio taping (KT) in shoulder subacromial impingement syndrome (SIS) when compared to sham taping applied in the same way with KT. Patients were randomized as group 1 (n = 21) KT group and group 2 (n = 20) sham-taping group. Taping was applied every three days, three times during the study period. We assessed all the patients at baseline, at the end of the taping period (12th day), and at one-month post-intervention. We assessed pain on the 100 mm visual analog scale (VAS). Shoulder range of motion (ROM), Constant Scores, and Nottingham Health Profile (NHP) scores were evaluated. Of the 41 participants, 13 were males (32%) and 28 were females (68%). The mean age was 45 ± 15 years (range 20-65 years). We documented a significant decrease in VAS for nocturnal pain, and Constant Score in both groups. The KT group showed additional significant change in NHP pain and physical activity scores. KT and sham taping generated similar results regarding pain and Constant Scores.
9. Selective activation of intra-muscular compartments within the trapezius muscle in subjects with Subacromial Impingement Syndrome. A case-control study
DEFF Research Database (Denmark)
Larsen, C M; Juul-Kristensen, B; Olsen, H B
2014-01-01
Neuromuscular control of the scapular muscles is important in the etiology of shoulder pain. Electromyographical (EMG) biofeedback in healthy people has been shown to support a selective activation of the lower compartment of the trapezius muscle, specifically. The aim of the present paper...... that individuals with SIS may benefit from biofeedback training to gain control of the neuromuscular function of the scapular muscle....... was to investigate whether patients with Subacromial Impingement Syndrome (SIS) were able to selectively activate the individual compartments within the trapezius muscle, with and without EMG biofeedback to the same extent as healthy controls (No-SIS). Fifteen SIS and 15 No-SIS participated in the study. Sessions...
10. Functional thoracic hyperkyphosis model for chronic subacromial impingement syndrome: an insight on evidence based "treat the cause" concept--a case study and literature review.
Science.gov (United States)
Nagarajan, M; Vijayakumar, P
2013-01-01
Recent evidences suggest functional thoracic hyperkyphosis (FTH) could be a different approach in the management of subacromial impingement syndrome (SIS). This case study aims firstly with the development of evidence informed FTH model for SIS. Secondly this study aimed to develop well defined multimodal physical therapy intervention for FTH and its related mechanical consequences in elderly patient with chronic SIS. As a result, Level IV positive evidence was found in both the short and long-term pain and disability of chronic SIS, using FTH model with 26 months of follow-up.
11. The Use of Physiotherapy among Patients with Subacromial Impingement Syndrome: Impact of Sex, Socio-Demographic and Clinical Factors
Science.gov (United States)
Christiansen, David Høyrup; Frost, Poul; Frich, Lars Henrik; Falla, Deborah; Svendsen, Susanne Wulff
2016-01-01
Background Physiotherapy with exercises is generally recommended in the treatment of patients with subacromial impingement syndrome (SIS). Objective We aimed to investigate the use of physiotherapy in patients with SIS in Danish hospital settings as part of initial non-surgical treatment and after SIS-related surgery and to evaluate to which extent sex, socio-demographic and clinical factors predict the use of physiotherapy. Methods Using national health registers, we identified 57,311 patients who had a first hospital contact with a diagnosis of ICD-10, groups M75.1–75.9, 1 July 2007 to 30 June 2011. Records of physiotherapy were extracted within 52 weeks after first contact (or until surgery), and for surgically treated patients within 26 weeks after surgery. Predictors of the use of physiotherapy after first contact and after surgery were analysed as time-to-event. Results Within 52 weeks after first contact, 43% of the patients had physiotherapy and 30% underwent surgery. Within 26 weeks after surgery, 80% had a record of physiotherapy. After first contact and after surgery, exercise was part of physiotherapy in 65% and 84% of the patients, respectively. A public hospital contact, physiotherapy before hospital contact, administrative region, female sex, a diagnosis of other or unspecified disorders (M75.8-M75.9), and surgical procedure predicted higher use of physiotherapy. Low education level predicted slightly lower use of physiotherapy after first contact, but not after surgery. Conclusion In patients with SIS in Danish hospital settings, physiotherapy was more often used after surgery than as part of initial non-surgical treatment. The use of physiotherapy was less common among men than women, whereas unequal use of physiotherapy in relation to education level was not noticeable. The use of physiotherapy with exercises in initial non-surgical treatment was relatively limited. PMID:26954692
12. Surgery for subacromial impingement syndrome in relation to intensities of occupational mechanical exposures across 10-year exposure time windows.
Science.gov (United States)
Dalbøge, Annett; Frost, Poul; Andersen, Johan Hviid; Svendsen, Susanne Wulff
2017-08-20
We aimed to identify intensities of occupational mechanical exposures (force, arm elevation and repetition) that do not entail an increased risk of surgery for subacromial impingement syndrome (SIS) even after prolonged durations of exposure. Additionally, we wanted to evaluate if exposure to hand-arm vibration (HAV) is an independent risk factor. We used data from a register-based cohort study of the entire Danish working population (n=2 374 403). During follow-up (2003-2008), 14 118 first-time events of surgery for SIS occurred. For each person, we linked register-based occupational codes (1993-2007) to a general population job exposure matrix to obtain year-by-year exposure intensities on measurement scales for force, upper arm elevation >90° and repetition and expert rated intensities of exposure to HAV. For 10-year exposure time windows, we calculated the duration of exposure at specific intensities above minimal (low, medium and high). We used a logistic regression technique equivalent to discrete survival analysis adjusting for cumulative effects of other mechanical exposures. We found indications of safe exposure intensities for repetition (median angular velocity 90° >2 min/day implied an increased risk reaching ORs of 1.7 and 1.5 after 10 years at low intensities. No associations were found for HAV. We found indications of safe exposure intensities for repetition. Any intensities of force and upper arm elevation >90° above minimal implied an increased risk across 10-year exposure time windows. No independent associations were found for HAV. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
13. Effectiveness of Shortwave Diathermy for Subacromial Impingement Syndrome and Value of Night Pain for Patient Selection: A Double-Blinded, Randomized, Placebo-Controlled Trial.
Science.gov (United States)
Yilmaz Kaysin, Meryem; Akpinar, Pinar; Aktas, Ilknur; Unlü Ozkan, Feyza; Silte Karamanlioglu, Duygu; Cagliyan Hartevioglu, Hulya; Vural, Nazan
2017-09-06
The aim of this study was to investigate the effectiveness of short wave diathermy (SWD) in patients with subacromial impingement syndrome. In this double-blinded, randomized, placebo-controlled trial, 57 patients (aged 35-65 yrs) were classified into night pain positive (NP[+]) (n = 28) and night pain negative (NP[-]) (n = 29) groups. Both groups were randomly assigned to SWD (NP[+], n = 14; NP[-], n = 14) and sham (NP[+], n = 15; NP[-], n = 14) subgroups. Visual analog scale, Constant-Murley Scale (CS), and Shoulder Disability Questionnaire (SDQ) scores were used for evaluation. There was only a significant difference in pain with activity at 1-mo (mean difference [MD], -1.65; 95% confidence interval, -3.01 to -0.28]) and 2-mo evaluations (MD, -2.1; 95% confidence interval, -3.51 to -0.69) between SWD versus sham groups. In the NP(+) SWD group, the CS pain score was significantly higher than in the NP(+) sham group at all evaluations after treatment. At 1 mo, the NP(-) SWD group showed significantly better pain, strength, total CS, and SDQ scores than the NP(-) sham group. At 2 mos, the pain, range of motion, strength, and total CS and SDQ scores were better in the NP(-) SWD group than in the NP(-) sham group (P diathermy is more effective in subacromial impingement syndrome without NP.
14. Effectiveness of Standardized Physical Therapy Exercises for Patients With Difficulty Returning to Usual Activities After Decompression Surgery for Subacromial Impingement Syndrome: Randomized Controlled Trial.
Science.gov (United States)
Christiansen, David Høyrup; Frost, Poul; Falla, Deborah; Haahr, Jens Peder; Frich, Lars Henrik; Andrea, Linda Christie; Svendsen, Susanne Wulff
2016-06-01
Little is known about the effectiveness of exercise programs after decompression surgery for subacromial impingement syndrome. For patients with difficulty returning to usual activities, special efforts may be needed to improve shoulder function. The purpose of this study was to evaluate the effectiveness at 3 and 12 months of a standardized physical therapy exercise intervention compared with usual care in patients with difficulty returning to usual activities after subacromial decompression surgery. A multicenter randomized controlled trial was conducted. The study was conducted in 6 public departments of orthopedic surgery, 2 departments of occupational medicine, and 2 physical therapy training centers in Central Denmark Region. One hundred twenty-six patients reporting difficulty returning to usual activities at the postoperative clinical follow-up 8 to 12 weeks after subacromial decompression surgery participated. A standardized exercise program consisting of physical therapist-supervised individual training sessions and home training was used. The primary outcome measure was the Oxford Shoulder Score. Secondary outcome measures were the Constant Score and the Fear-Avoidance Beliefs Questionnaire. At 3 and 12 months, follow-up data were obtained for 92% and 83% of the patients, respectively. Intention-to-treat analyses suggested a between-group difference on the Oxford Shoulder Score favoring the exercise group at 3 months, with an adjusted mean difference of 2.0 (95% confidence interval=-0.5, 4.6), and at 12 months, with an adjusted mean difference of 5.8 (95% confidence interval=2.8, 8.9). Significantly larger improvements for the exercise group were observed for most secondary and supplementary outcome measures. The nature of the exercise intervention did not allow blinding of patients and care providers. The standardized physical therapy exercise intervention resulted in statistically significant and clinically relevant improvement in shoulder pain and
15. A randomized clinical study of the heated lidocaine/tetracaine patch versus subacromial corticosteroid injection for the treatment of pain associated with shoulder impingement syndrome.
Science.gov (United States)
Radnovich, Richard; Trudeau, Jeremiah; Gammaitoni, Arnold R
2014-01-01
Treatment for pain due to shoulder impingement syndrome (SIS) typically begins conservatively with nonsteroidal anti-inflammatory drugs and physical therapy and can include subacromial injection of corticosteroids, particularly in patients unresponsive to conservative measures. The heated lidocaine/tetracaine (HLT) patch has been reported to reduce SIS pain in a small case series. This was a prospective, randomized, open-label clinical trial in which adult patients with SIS pain lasting at least 14 days, with an average intensity of ≥4 on a 0-10 scale (0= no pain, 10= worst pain) were randomized to treatment with the HLT patch or a single subacromial injection of triamcinolone acetonide (10 mg). Patients in the HLT patch group applied a single HLT patch to the shoulder for 4 hours twice daily, with a 12-hour interval between treatments during the first 14 days, and could continue to use the patch on an as-needed basis (up to twice daily) during the second 14-day period. No treatment was allowed in the final 14-day period. At baseline and at days 14, 28, and 42, patients rated their pain and pain interference with specific activities (0-10 scale). Sixty patients enrolled in the study (average age =51 years, range 18-75, n=21 female). Average pain scores declined from 6.0±1.6 at baseline to 3.5±2.4 at day 42 in the HLT patch group (n=29, Pwork, or sleep; and range of motion. No significant between-group differences were seen for any pain or pain interference scores at any time point. These results suggest that short-term, noninvasive treatment with the HLT patch has similar efficacy to subacromial corticosteroid injections for the treatment of pain associated with SIS.
16. The subacromial impingement syndrome of the shoulder treated by conventional physiotherapy, self-training, and a shoulder brace: results of a prospective, randomized study.
Science.gov (United States)
Walther, Markus; Werner, Andreas; Stahlschmidt, Theresa; Woelfel, Rainer; Gohlke, Frank
2004-01-01
This prospective, randomized trial was performed to compare the results of treating subacromial impingement syndrome of the shoulder by a guided self-training program with the treatment by conventional physiotherapy or a functional brace. Sixty patients with the diagnosis of an outlet impingement syndrome of the shoulder (Neer I and II) were treated either by strengthening the depressors of the humeral head with a guided self-training program, by conventional physiotherapy, or by wearing a functional brace. The Constant-Murley score was assessed after 6 and 12 weeks. Shoulder pain was monitored with a visual analog scale. All three groups showed a significant improvement in shoulder function as well as a significant reduction in pain. There were no statistically significant differences among the groups. Guided self-training can lead to results similar to those of conventional physiotherapy. The comparable effect of the functional brace remains unclear and might be explained by an influence on proprioception.
17. Does taping in addition to physiotherapy improve the outcomes in subacromial impingement syndrome? A systematic review.
Science.gov (United States)
Saracoglu, Ismail; Emuk, Yusuf; Taspinar, Ferruh
2018-04-01
Taping is used with or without other interventions for many purposes, especially to manage pain and improve functional activity in patients with shoulder pain. The aim of this review was to determine whether any taping technique in addition to physiotherapy care is more effective than physiotherapy care alone in patients with shoulder impingement syndrome. A systematic search of Cochrane Database of Systematic Review, MEDLINE (EBSCO), Physiotherapy Evidence Database (PEDro), CINAHL (EBSCO), PUBMED, AMED, EMBASE (OVID), The Kinesio Kinesio® Taping Method, Kinesio® Tex Tape UK and International websites ( www.kinesiotaping.co.uk ; www.kinesiotaping.com ) was conducted to June 2015. The outcome measures were pain, disability, range of motion and muscle strength. As data were not suitable for meta-analysis, narrative synthesis were applied. Three randomized controlled trials and one controlled trial (135 patients) were included. The results were conflicting and weak on the effectiveness of taping as an adjunct therapy for improvement of pain, disability, range of motion and muscle strength. Clinical taping in addition to physiotherapy interventions (e.g. exercise, electrotherapy, and manual therapy) might be an optional modality for managing patients with shoulder impingement syndrome, especially for the initial stage of the treatment; however, we need further robust, placebo controlled and consistent studies to prove whether it is more effective than physiotherapy interventions without taping.
18. Does acromioplasty result in favorable clinical and radiologic outcomes in the management of chronic subacromial pain syndrome? A double-blinded randomized clinical trial with 9 to 14 years' follow-up.
Science.gov (United States)
Kolk, Arjen; Thomassen, Bregje J W; Hund, Hajo; de Witte, Pieter Bas; Henkus, Hans-Erik; Wassenaar, Willem G; van Arkel, Ewoud R A; Nelissen, Rob G H H
2017-08-01
The treatment effect of acromioplasty for chronic subacromial pain syndrome (SAPS) on long-term shoulder function and rotator cuff deterioration has still to be determined. This study aimed to determine the long-term clinical and radiologic treatment effect of arthroscopic acromioplasty in patients with chronic SAPS. In this double-blind, randomized clinical trial, 56 patients with chronic SAPS (median age, 47 years; age range, 31-60 years) were randomly allocated to arthroscopic bursectomy alone or to bursectomy combined with acromioplasty and were followed up for a median of 12 years. The primary outcome was the Constant score. Secondary outcomes included the Simple Shoulder Test, visual analog scale (VAS) for pain, VAS for shoulder functionality, and rotator cuff integrity assessed with magnetic resonance imaging or ultrasound. A total of 43 patients (77%) were examined at a median of 12 years' follow-up. Intention-to-treat analysis at 12 years' follow-up did not show a significant additional treatment effect of acromioplasty on bursectomy alone in improvement in Constant score (5 points; 95% confidence interval, -5.1 to 15.6), Simple Shoulder Test score, VAS score for pain, or VAS score for shoulder function. The prevalence of rotator cuff tears was not significantly different between the bursectomy group (17%) and acromioplasty group (10%). There were no relevant additional effects of arthroscopic acromioplasty on bursectomy alone with respect to clinical outcomes and rotator cuff integrity at 12 years' follow-up. These findings bring the effectiveness of acromioplasty into question and may support the idea of a more conservative approach in the initial treatment of SAPS. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
19. Effect of corticosteroid injections versus physiotherapy on pain, shoulder range of motion and shoulder function in patients with subacromial impingement syndrome: A systematic review and meta-analysis
Directory of Open Access Journals (Sweden)
Marlette Burger
2016-02-01
Full Text Available Background: Subacromial impingement syndrome (SIS is one of the most common causes of shoulder pain. Limited research has been conducted into the efficacy of corticosteroid injections (CSIs compared to physiotherapy in the management of SIS.Objective: To critically appraise and establish the best available evidence for the effectiveness of CSI in comparison with physiotherapy for the management of pain, shoulder range of motion (ROM and shoulder function in patients with SIS.Methodology: Seven databases were searched from inception to February 2016, namely PubMed, Science Direct, EBSCO Host: SPORTDiscus, EBSCO Host: CINAHL, Cochrane, Scopus and PEDro. The main search terms were shoulder impingement syndrome and/or subacromial impingement syndrome, corticosteroid injections and/or steroid injections, physical therapy and/or physiotherapy. Only randomised controlled trials (RCTs were considered for inclusion. The articles were appraised according to the PEDro scale. The Revman© Review Manager Software was used to combine the results of shoulder function and the data were illustrated in forest plots.Results: The PEDro scores of the three RCTs that qualified for this review ranged from 7 to 8/10. There is Level II evidence suggesting that besides a significant improvement in shoulder function in favour of CSI at 6–7 weeks follow-up (p < 0.0001, no evidence was found for the superiority of CSIs compared with physiotherapy for pain, ROM and shoulder function in the short- (1–3 months, mid- (6 months and long term (12 months.Conclusion: In patients with SIS only a short term significant improvement in shoulder function was found in favour of CSIs.
20. A randomized clinical study of the heated lidocaine/tetracaine patch versus subacromial corticosteroid injection for the treatment of pain associated with shoulder impingement syndrome
Directory of Open Access Journals (Sweden)
2014-12-01
Full Text Available Richard Radnovich,1 Jeremiah Trudeau,2 Arnold R Gammaitoni3 1Injury Care Medical Center, Boise, ID, USA; 2Analgesic Solutions, Natick, MA, USA; 3Nuvo Research Inc., West Chester, PA, USA Background: Treatment for pain due to shoulder impingement syndrome (SIS typically begins conservatively with nonsteroidal anti-inflammatory drugs and physical therapy and can include subacromial injection of corticosteroids, particularly in patients unresponsive to conservative measures. The heated lidocaine/tetracaine (HLT patch has been reported to reduce SIS pain in a small case series. Methods: This was a prospective, randomized, open-label clinical trial in which adult patients with SIS pain lasting at least 14 days, with an average intensity of ≥4 on a 0–10 scale (0= no pain, 10= worst pain were randomized to treatment with the HLT patch or a single subacromial injection of triamcinolone acetonide (10 mg. Patients in the HLT patch group applied a single HLT patch to the shoulder for 4 hours twice daily, with a 12-hour interval between treatments during the first 14 days, and could continue to use the patch on an as-needed basis (up to twice daily during the second 14-day period. No treatment was allowed in the final 14-day period. At baseline and at days 14, 28, and 42, patients rated their pain and pain interference with specific activities (0–10 scale. Results: Sixty patients enrolled in the study (average age =51 years, range 18–75, n=21 female. Average pain scores declined from 6.0±1.6 at baseline to 3.5±2.4 at day 42 in the HLT patch group (n=29, P<0.001 and from 5.6±1.2 to 3.2±2.6 in the injection group (n=31, P<0.001. Similar improvements were seen in each group for worst pain; pain interference with general activity, work, or sleep; and range of motion. No significant between-group differences were seen for any pain or pain interference scores at any time point. Conclusion: These results suggest that short-term, noninvasive treatment
1. A double-blind randomized controlled trial comparing the effects of subacromial injection with corticosteroid versus NSAID in patients with shoulder impingement syndrome.
Science.gov (United States)
Min, Kyong Su; St Pierre, Patrick; Ryan, Paul M; Marchant, Bryant G; Wilson, Christopher J; Arrington, Edward D
2013-05-01
The objective of this study was to compare the efficacy of subacromial injection of triamcinolone compared to injection of ketorolac in the treatment of external shoulder impingement syndrome. Thirty-two patients diagnosed with external shoulder impingement syndrome were included in this double-blinded randomized controlled clinical trial. Each patient was randomized into the steroid group or nonsteroidal anti-inflammatory drugs (NSAID) group. The steroid syringe contained 40 mg triamcinolone; and the NSAID syringe contained 60 mg ketorolac. Each patient was evaluated in terms of arc of motion, visual analog scale (VAS) for evaluating pain, and the UCLA (The University of California at Los Angeles) shoulder rating scale. At 1 month follow-up, both treatment arms resulted in increased range of motion and decreased pain. The steroid group decreased in active abduction while the NSAID group increased (steroid: 134°, NSAID: 151°, P = .03). The mean improvement in the UCLA shoulder rating scale at 4 weeks was 7.15 for the NSAID group and 2.13 for the steroid group (P = .03). Subgroup analysis of the UCLA scale demonstrated an increase in both forward flexion strength (P = .04) and patient satisfaction (P = .03) in the NSAID group. No significant difference could be seen in all other outcome measures. In this study, an injection of ketorolac resulted in greater improvements in the UCLA shoulder rating scale than an injection of triamcinolone at 4 weeks follow-up. While both triamcinolone and ketorolac are effective in the treatment of isolated subacromial impingement, ketorolac appears to have equivalent if not superior efficacy; all the while decreasing patient exposure to the potential side-effects of corticosteroids. Published by Mosby, Inc.
2. Immediate changes in pressure pain sensitivity after thoracic spinal manipulative therapy in patients with subacromial impingement syndrome: A randomized controlled study.
Science.gov (United States)
Kardouni, Joseph R; Shaffer, Scott W; Pidcoe, Peter E; Finucane, Sheryl D; Cheatham, Seth A; Michener, Lori A
2015-08-01
Thoracic SMT can improve symptoms in patients with subacromial impingement syndrome. However, at this time the mechanisms of SMT are not well established. It is possible that changes in pain sensitivity may occur following SMT. To assess the immediate pain response in patients with shoulder pain following thoracic spinal manipulative therapy (SMT) using pressure pain threshold (PPT), and to assess the relationship of change in pain sensitivity to patient-rated outcomes of pain and function following treatment. Randomized Controlled Study. Subjects with unilateral subacromial impingement syndrome (n = 45) were randomly assigned to receive treatment with thoracic SMT or sham thoracic SMT. PPT was measured at the painful shoulder (deltoid) and unaffected regions (contralateral deltoid and bilateral lower trapezius areas) immediately pre- and post-treatment. Patient-rated outcomes were pain (numeric pain rating scale - NPRS), function (Pennsylvania Shoulder Score - Penn), and global rating of change (GROC). There were no significant differences between groups in pre-to post-treatment changes in PPT (p ≥ 0.583) nor were there significant changes in PPT within either group (p ≥ 0.372) following treatment. NPRS, Penn and GROC improved across both groups (p < 0.001), but there were no differences between the groups (p ≥ 0.574). There were no differences in pressure pain sensitivity between participants receiving thoracic SMT versus sham thoracic SMT. Both groups had improved patient-rated pain and function within 24-48 h of treatment, but there was no difference in outcomes between the groups. Published by Elsevier Ltd.
3. SHORT‐TERM EFFECTS OF INSTRUMENT‐ASSISTED SOFT TISSUE MOBILIZATION ON PAIN FREE RANGE OF MOTION IN A WEIGHTLIFTER WITH SUBACROMIAL PAIN SYNDROME
Science.gov (United States)
Coviello, Joseph Paul; Reynolds, Timothy James
2017-01-01
Background and Purpose While there is limited evidence supporting the use of soft tissue mobilization techniques for Subacromial Pain Syndrome (SAPS), synonymous with subacromial impingement syndrome, previous studies have reported successful outcomes using soft tissue mobilization as a treatment technique. The purpose of this case report is to document the results of Instrument‐Assisted Soft Tissue Mobilization (IASTM) for the treatment of SAPS. Case Description Diagnosis was reached based on the subject's history, tenderness to palpation, and four out of five positive tests in the diagnostic cluster. Treatment consisted of three visits where the IASTM technique was applied to the pectoral muscles as well as periscapular musculature followed by retesting pain‐free shoulder flexion active range of motion (AROM) and Numerical Pain Rating Scale (NPRS) during active shoulder flexion. Scapulothoracic mobilization and stretching were performed after AROM measurement. Outcomes The subject reported an NPRS of 0/10 and demonstrated improvements in pain free flexion AROM in each of the three treatment sessions post‐IASTM: 85 ° to 181 °, 110 ° to 171 °, and 163 ° to 174 ° with some carryover in pain reduction and pain free AROM to the next treatment. Through three treatments, DASH score improved by 17.34%, Penn Shoulder Score improved 29%, worst NPRS decreased from 4/10 to 0/10, and a GROC score of 6. Discussion IASTM may have a beneficial acute effect on pain free shoulder flexion. In conjunction with scapulothoracic mobilizations and stretching, IASTM may improve function, decrease pain, and improve patient satisfaction. While this technique will not ameliorate the underlying pathomechanics contributing to SAPS, it may serve as a valuable tool to restore ROM and decrease pain allowing the patient to reap the full benefits of a multi‐modal treatment approach. Level of Evidence 5 PMID:28217425
4. SHORT-TERM EFFECTS OF INSTRUMENT-ASSISTED SOFT TISSUE MOBILIZATION ON PAIN FREE RANGE OF MOTION IN A WEIGHTLIFTER WITH SUBACROMIAL PAIN SYNDROME.
Science.gov (United States)
Coviello, Joseph Paul; Kakar, Rumit Singh; Reynolds, Timothy James
2017-02-01
While there is limited evidence supporting the use of soft tissue mobilization techniques for Subacromial Pain Syndrome (SAPS), synonymous with subacromial impingement syndrome, previous studies have reported successful outcomes using soft tissue mobilization as a treatment technique. The purpose of this case report is to document the results of Instrument-Assisted Soft Tissue Mobilization (IASTM) for the treatment of SAPS. Diagnosis was reached based on the subject's history, tenderness to palpation, and four out of five positive tests in the diagnostic cluster. Treatment consisted of three visits where the IASTM technique was applied to the pectoral muscles as well as periscapular musculature followed by retesting pain-free shoulder flexion active range of motion (AROM) and Numerical Pain Rating Scale (NPRS) during active shoulder flexion. Scapulothoracic mobilization and stretching were performed after AROM measurement. The subject reported an NPRS of 0/10 and demonstrated improvements in pain free flexion AROM in each of the three treatment sessions post-IASTM: 85 ° to 181 °, 110 ° to 171 °, and 163 ° to 174 ° with some carryover in pain reduction and pain free AROM to the next treatment. Through three treatments, DASH score improved by 17.34%, Penn Shoulder Score improved 29%, worst NPRS decreased from 4/10 to 0/10, and a GROC score of 6. IASTM may have a beneficial acute effect on pain free shoulder flexion. In conjunction with scapulothoracic mobilizations and stretching, IASTM may improve function, decrease pain, and improve patient satisfaction. While this technique will not ameliorate the underlying pathomechanics contributing to SAPS, it may serve as a valuable tool to restore ROM and decrease pain allowing the patient to reap the full benefits of a multi-modal treatment approach. 5.
5. Effects of Low-Load Exercise on Postneedling-Induced Pain After Dry Needling of Active Trigger Point in Individuals With Subacromial Pain Syndrome.
Science.gov (United States)
Salom-Moreno, Jaime; Jiménez-Gómez, Laura; Gómez-Ahufinger, Victoria; Palacios-Ceña, María; Arias-Buría, José L; Koppenhaver, Shane L; Fernández-de-Las-Peñas, César
2017-05-05
6. A randomized clinical study of the heated lidocaine/tetracaine patch versus subacromial corticosteroid injection for the treatment of pain associated with shoulder impingement syndrome
Science.gov (United States)
Radnovich, Richard; Trudeau, Jeremiah; Gammaitoni, Arnold R
2014-01-01
Background Treatment for pain due to shoulder impingement syndrome (SIS) typically begins conservatively with nonsteroidal anti-inflammatory drugs and physical therapy and can include subacromial injection of corticosteroids, particularly in patients unresponsive to conservative measures. The heated lidocaine/tetracaine (HLT) patch has been reported to reduce SIS pain in a small case series. Methods This was a prospective, randomized, open-label clinical trial in which adult patients with SIS pain lasting at least 14 days, with an average intensity of ≥4 on a 0–10 scale (0= no pain, 10= worst pain) were randomized to treatment with the HLT patch or a single subacromial injection of triamcinolone acetonide (10 mg). Patients in the HLT patch group applied a single HLT patch to the shoulder for 4 hours twice daily, with a 12-hour interval between treatments during the first 14 days, and could continue to use the patch on an as-needed basis (up to twice daily) during the second 14-day period. No treatment was allowed in the final 14-day period. At baseline and at days 14, 28, and 42, patients rated their pain and pain interference with specific activities (0–10 scale). Results Sixty patients enrolled in the study (average age =51 years, range 18–75, n=21 female). Average pain scores declined from 6.0±1.6 at baseline to 3.5±2.4 at day 42 in the HLT patch group (n=29, P<0.001) and from 5.6±1.2 to 3.2±2.6 in the injection group (n=31, P<0.001). Similar improvements were seen in each group for worst pain; pain interference with general activity, work, or sleep; and range of motion. No significant between-group differences were seen for any pain or pain interference scores at any time point. Conclusion These results suggest that short-term, noninvasive treatment with the HLT patch has similar efficacy to subacromial corticosteroid injections for the treatment of pain associated with SIS. PMID:25525385
7. Shoulder function and work disability after decompression surgery for subacromial impingement syndrome: a randomised controlled trial of physiotherapy exercises and occupational medical assistance.
Science.gov (United States)
Svendsen, Susanne W; Christiansen, David H; Haahr, Jens Peder; Andrea, Linda C; Frost, Poul
2014-06-21
Surgery for subacromial impingement syndrome is often performed in working age and postoperative physiotherapy exercises are widely used to help restore function. A recent Danish study showed that 10% of a nationwide cohort of patients retired prematurely within two years after surgery. Few studies have compared effects of different postoperative exercise programmes on shoulder function, and no studies have evaluated workplace-oriented interventions to reduce postoperative work disability. This study aims to evaluate the effectiveness of physiotherapy exercises and occupational medical assistance compared with usual care in improving shoulder function and reducing postoperative work disability after arthroscopic subacromial decompression. The study is a mainly pragmatic multicentre randomised controlled trial. The trial is embedded in a cohort study of shoulder patients referred to public departments of orthopaedic surgery in Central Denmark Region. Patients aged ≥18-≤63 years, who still have shoulder symptoms 8-12 weeks after surgery, constitute the study population. Around 130 participants are allocated to: 1) physiotherapy exercises, 2) occupational medical assistance, 3) physiotherapy exercises and occupational medical assistance, and 4) usual care. Intervention manuals allow individual tailoring. Primary outcome measures include Oxford Shoulder Score and sickness absence due to symptoms from the operated shoulder. Randomisation is computerised with allocation concealment by randomly permuted block sizes. Statistical analyses will primarily be performed according to the intention-to-treat principle. The paper presents the rationale, design, methods, and operational aspects of the Shoulder Intervention Project (SIP). SIP evaluates a new rehabilitation approach, where physiotherapy and occupational interventions are provided in continuity of surgical episodes of care. If successful, the project may serve as a model for rehabilitation of surgical shoulder
8. The effect of interferential current therapy on patients with subacromial impingement syndrome: a randomized, double-blind, sham-controlled study.
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Nazligul, Tuba; Akpinar, Pinar; Aktas, Ilknur; Unlu Ozkan, Feyza; Cagliyan Hartevioglu, Hulya
2017-09-11
Although interferential current (IFC) is a common electrotherapeutic modality used to treat musculoskeletal pain, there is not any randomized controlled trial investigating its clinical efficacy in subacromial impingement syndrome (SAIS). Investigation of effectiveness of IFC treatment in patients with SAIS. Randomized, double-blind, sham-controlled study. Physical medicine and rehabilitation outpatient clinic. Patients (n=65) between 25 and 65 years of age, with a diagnosis of SAIS according to clinical evaluation and subacromial injection test. Patients were randomly distributed into two groups: 1) active IFC group (n=33); 2) sham IFC group (n=32). Exercise, cryotherapy, and a non-steroidal anti-inflammatory drug (NSAID) were given to both groups. Ten sessions of IFC with bipolar method were applied to the active IFC group daily 20 minutes per session, 5 days per week, for 2 weeks while sham IFC was applied to the sham IFC group with the same protocol. Visual analog scale (VAS), Constant scores, and Shoulder Disability Questionnaire (SDQ) were used for evaluation at baseline, immediately post-treatment, and 1 month post-treatment. Both the patients and the researcher who assessed the outcomes were blinded to the treatment protocol throughout the study period. Sixty of the 65 patients (active IFC group n=30, sham IFC group n=30) completed the study, 3 patients from active IFC, 2 from sham IFC group dropped during the follow up period. Statistically significant improvement was observed in all parameters of both groups immediately and 1 month post-treatment (p0.05). Our results demonstrated that IFC therapy does not provide additional benefit to NSAID, cryotherapy, and exercise program in treatment of SAIS. Our study responds to the needs of the lack of evidence in the field of rehabilitation. IFC therapy does not provide additional benefit for the treatment of SAIS.
9. Cost-effectiveness of exercise therapy after corticosteroid injection for moderate to severe shoulder pain due to subacromial impingement syndrome: a trial-based analysis.
Science.gov (United States)
Jowett, Sue; Crawshaw, Dickon P; Helliwell, Philip S; Hensor, Elizabeth M A; Hay, Elaine M; Conaghan, Philip G
2013-08-01
To perform a cost-effectiveness analysis of subacromial corticosteroid injection combined with exercise compared with exercise alone in patients with moderate to severe shoulder pain from subacromial impingement syndrome. A within-trial cost-effectiveness analysis with 232 patients randomized to physiotherapy-led injection combined with exercise (n = 115) or exercise alone (n = 117). The analysis was from a health care perspective with 24-week follow-up. Resource use information was collected from all patients on interventions, medication, primary and secondary care contacts, private health care use and over-the-counter purchases. The measure of outcome was quality-adjusted life years (QALYs), calculated from EQ-5D responses at baseline and three further time points. An incremental cost-effectiveness analysis was conducted. Mean per patient NHS costs (£255 vs £297) and overall health care costs (£261 vs £318) were lower in the injection plus exercise arm, but this difference was not statistically significant. Total QALYs gained were very similar in the two trial arms (0.3514 vs 0.3494 QALYs), although slightly higher in the injection plus exercise arm, indicating that injection plus exercise may be the dominant treatment option. At a willingness to pay of £20,000 per additional QALY gained, there was a 61% probability that injection plus exercise was the most cost-effective option. Injection plus exercise delivered by therapists may be a cost-effective use of resources compared with exercise alone and lead to lower health care costs and less time off work. International Standard Randomised Controlled Trial Number Register, http://www.controlled-trials.com/isrctn/, ISRCT 25817033.
10. Effectiveness of Standardized Physiotherapy Exercises for Patients With Difficulty Returning to Usual Activities After Decompression Surgery for Subacromial Impingement Syndrome
DEFF Research Database (Denmark)
Christiansen, David Høyrup; Frost, Poul; Falla, Deborah
2016-01-01
was to evaluate the effectiveness at 3 and 12 months of a standardized physical therapy exercise intervention compared with usual care in patients with difficulty returning to usual activities after subacromial decompression surgery. DESIGN: A multicenter randomized controlled trial was conducted. SETTING......: The study was conducted in 6 public departments of orthopedic surgery, 2 departments of occupational medicine, and 2 physical therapy training centers in Central Denmark Region. PATIENTS: One hundred twenty-six patients reporting difficulty returning to usual activities at the postoperative clinical follow...... outcome measures. LIMITATIONS: The nature of the exercise intervention did not allow blinding of patients and care providers. CONCLUSION: The standardized physical therapy exercise intervention resulted in statistically significant and clinically relevant improvement in shoulder pain and function at 12...
11. Intra and inter-examiner reliability of the subacromial impingement index
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Ramos, Carlos Eduardo Sala; Ferreira, Felipe Varella; Carvalho Sposito, Guilherme de; Nogueira-Barbosa, Marcello Henrique; Oliveira, Anamaria Siriani de [University of Sao Paulo, Ribeirao Preto School of Medicine, Ribeirao Preto, SP (Brazil)
2010-01-15
The present study aimed to assess the reliability of intra and inter-examiner subacromial impingement index (SII) measures obtained from radiographs. Thirty-six individuals were enrolled and divided into two groups: control group, composed of 18 volunteers in good general health without shoulder problems, and a group of 18 patients with subacromial impingement syndrome (SIS). Radiographic images were taken with the dominant upper limb in neutral rotation, while the volunteers held their arm at 90 of abduction in the frontal plane. The beam of radiation at 30 craniocaudal inclination was used to provide an antero-posterior image view. Three blinded examiners each performed three measurements from the subacromial space (SS) and the anatomical neck of the humerus (NH). The SII was calculated as the ratio of the SS and the NH measures. The mean values of SII were compared using t-tests. The intra-class correlation coefficient (ICC) was used to assess intra- and inter-examiner reliability of the measures. The mean values of SII were greater for the control group (0.12) than for the SIS group (0.08; p = 0.0071). SII measurements showed excellent intra (0.96-0.99) and inter-examiner reliability (0.94) for both the control and SIS group. The results of this study show the potential use of the SII; a greater mean value for the control group compared to the SIS group and excellent reliability for intra- and inter-examiner measurement. Validation studies of the index should be conducted to correlate the index with clinical findings from subacromial impingement syndrome. (orig.)
12. Kazuistika fyzioterapeutické péče o pacienta s diagnózou syndrom rotátorové manžety
OpenAIRE
Janatová, Klára
2014-01-01
Title: Case study of physiotherapy care of a patient diagnosed with rotator cuff syndrome. Objectives: Summary of theoretical knowledge of the rotator cuff conditions and their treatment using physical therapy. Case study of a patient diagnosed with rotator cuff syndrome. Methods: The general part covers conditions of the rotator cuff, the impingement syndrome and physiotherapy methods used in pathology of the subacromial space. It also includes anatomy, kinesiology and biomechanics of the sh...
13. Clinical and radiological outcome of conservative vs. surgical treatment of atraumatic degenerative rotator cuff rupture : design of a randomized controlled trial
NARCIS (Netherlands)
Heerspink, Frederik O. Lambers; Hoogeslag, Roy A. G.; Diercks, Ron L.; van Eerden, Pepijn J. M.; van den Akker-Scheek, Inge; van Raay, Jos J. A. M.
2011-01-01
Background: Subacromial impingement syndrome is a frequently observed disorder in orthopedic practice. Lasting symptoms and impairment may occur when a subsequent atraumatic rotator cuff rupture is also present. However, degenerative ruptures of the rotator cuff can also be observed in asymptomatic
14. Responsiveness and minimal important change of the Norwegian version of the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH) in patients with subacromial pain syndrome.
Science.gov (United States)
Rysstad, Tarjei; Røe, Yngve; Haldorsen, Benjamin; Svege, Ida; Strand, Liv Inger
2017-06-08
The Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH) is a valid and reliable patient-reported outcome measure (PROM). It was designed to measure physical disability and symptoms in patients with musculoskeletal disorders of the upper extremity, and is one of the most commonly used PROMs for patients with shoulder pain. The aim of this study was to examine responsiveness, the smallest detectable change (SDC) and the minimal important change (MIC) of the DASH, in line with international (COSMIN) recommendations. The study sample consisted of 50 patients with subacromial pain syndrome, undergoing physical therapy for 3-4 months. Responsiveness to change was examined by calculating area under the receiver operating characteristic curves (AUC) and testing a priori-formulated hypothesis regarding correlations with changes in other instruments that measuring the same construct. The SDC was calculated using a test re-test protocol, and the MIC was calculated by the anchor-based MIC distribution. MIC values for patients with low and high baseline scores were also calculated. DASH appeared to be responsive, as it was able to distinguish patients who reported to be improved from those unchanged (AUC 0.77). All of the hypotheses were accepted. The SDC was 11.8, and the MIC was 4.4. This study shows that the Norwegian version of the DASH has good responsiveness to change and may thus be recommended to measure outcome in patients with shoulder pain in Norway.
15. Effectiveness of microwave diathermy on pain, functional capacity, muscle strength, quality of life, and depression in patients with subacromial impingement syndrome: a randomized placebo-controlled clinical study.
Science.gov (United States)
Akyol, Yesim; Ulus, Yasemin; Durmus, Dilek; Canturk, Ferhan; Bilgici, Ayhan; Kuru, Omer; Bek, Yuksel
2012-10-01
The aim of this clinical trial was to evaluate the effectiveness of therapeutic MD on pain, functional capacity, muscle strength, quality of life, and depression in patients with subacromial impingement syndrome (SIS). A total of 40 inpatient subjects with definite SIS were included in this study. These patients were sequentially randomized into 2 groups. Group 1 (n = 20) received therapeutic MD. Group 2 (n = 20) was served as control group and received sham MD. Superficial heat and exercise program were given to both groups. Both of the programs were performed 5 times weekly for 3 weeks. Patients were assessed before treatment (BT), after treatment (AT), and at a 1-month follow-up (F). Outcome measures included visual analogue scale, goniometry, Shoulder Pain and Disability Index, Shoulder Disability Questionnaire, shoulder isokinetic muscle testing, handgrip strength, Short Form 36, and Beck Depression Index. The patients with SIS in each group had significant improvements in pain, shoulder ROM, disability, shoulder muscles and grip strength, quality of life, and depression AT and F when compared with their initial status (P 0.05). A 2,450-MHz MD regimen showed no beneficial effects in patients with SIS, so the superficial heat and exercise program, as it is efficient, may be preferable for the treatment of SIS, alone.
16. Comparison of virtual reality exergaming and home exercise programs in patients with subacromial impingement syndrome and scapular dyskinesis: Short term effect.
Science.gov (United States)
Pekyavas, Nihan Ozunlu; Ergun, Nevin
2017-05-01
The aim of this study was to compare the short term effects of home exercise program and virtual reality exergaming in patients with subacromial impingement syndrome (SAIS). A total of 30 patients with SAIS were randomized into two groups which are Home Exercise Program (EX Group) (mean age: 40.6 ± 11.7 years) and Virtual Reality Exergaming Program (WII Group) (mean age: 40.33 ± 13.2 years). Subjects were assessed at the first session, at the end of the treatment (6 weeks) and at 1 month follow-up. The groups were assessed and compared with Visual Analogue Scale (based on rest, activity and night pain), Neer and Hawkins Tests, Scapular Retraction Test (SRT), Scapular Assistance Test (SAT), Lateral Scapular Slide Test (LSST) and shoulder disability (Shoulder Pain and Disability Index (SPADI)). Intensity of pain was significantly decreased in both groups with the treatment (p < 0.05). The WII Group had significantly better results for all Neer test, SRT and SAT than the EX Group (p < 0.05). Virtual reality exergaming programs with these programs were found more effective than home exercise programs at short term in subjects with SAIS. Level I, Therapeutic study. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.
17. LIPOMA ARBORESCENS: RARE CASE OF ROTATOR CUFF TEAR ASSOCIATED WITH THE PRESENCE OF LIPOMA ARBORESCENS IN THE SUBACROMIAL-SUBDELTOID AND GLENOHUMERAL BURSA.
Science.gov (United States)
Benegas, Eduardo; Neto, Arnaldo Amado Ferreiro; Teodoro, Daniel Sabatini; da Silva, Marcos Vinícius Muriano; de Oliveira, Augusto Medaglia; Filippi, Renée Zon; de Santis Prada, Flávia
2012-01-01
Lipoma arborescens is a rare intra-articular disease that is usually monoarticular and is characterized by extensive proliferation of the synovial villi and hyperplasia of the subsynovial fat. The synovial tissue is progressively replaced by mature fat cells in the synovial membrane. The present study reports a case of a rare condition of lipoma arborescens that was simultaneously intra-articular (glenohumeral joint) and in the subacromial-subdeltoid bursa, in association with a torn supraspinatus tendon. The clinical, histological and radiographic presentations and treatment are discussed here. The description of this case includes radiographic and magnetic resonance evaluations and pathological examination. Although lipoma arborescens is a rare condition, it should be taken into consideration in cases presenting synovial hyperproliferation and synovial fat replacement.
18. PERBANDINGAN ANTARA KOMBINASI LATIHAN STABILISASI BAHU DAN TRAKSI HUMERUS KE INFERIOR DENGAN KOMBINASI LATIHAN FUNGSIONAL BAHU DAN TRAKSI HUMERUS KE INFERIOR DALAM MENURUNKAN DISABILITAS BAHU DAN LENGAN PADA SUBACROMIAL IMPINGEMENT SYNDROME MAHASISWA AKAD
Directory of Open Access Journals (Sweden)
2015-08-01
Full Text Available Shoulder impingement causing interference on the motion of the shoulder joint activities and result in functional activity disorder. These injuries usually are caused by faulty movement, overuse, poor posture, occupational factors and trauma. This will cause a burden on one part of the body and cause imbalances in anatomy, which will eventually lead to disruption of the body that experienced work. This study aimed to investigate the effect of functional shoulder exercise and traction humerus to inferior with shoulder stabilization exercises and traction humerus to inferior to the decline in the shoulder and arm disabilities in subacromial impingement syndrome. This research method was experimental clinical trials with pre test and post test group design. Population student Academy Physiotherapy Widya Husada Semarang, which consists of 3 men and 12 women, aged between 18-21 years, divided into two groups. Group I was given Shoulder Stabilization exercises and Traction humerus to Inferior (n=7 and group II Functional Shoulder Exercise and Traction humerus to Inferior (n=8. This research was conducted for 3 weeks. Measurement of the value of disability shoulder and arm by using the Shoulder Pain and Disability Index (SPADI. The test results on the group I average value pre 34.17, SB = 6.31, and the average value of post 11.54, SB = 4.02, p = 0.001 found significant differences obtained test results paired sample t-test, and testing group II average value pre 40.18, SB = 3.53, and the average value of post 7.82, SB = 1.57, p = 0.001 found significant differences obtained test results paired sample t-test. Comparison of Group I and II, p = 0.005 there were significant differences, test results obtained independent sample t-test. Conclusions: The combination of shoulder stabilization exercises and traction humerus to inferior can reduce disability shoulder and arm on subacromial impingement syndrome. The combination functional shoulder exercise and
19. Stromal cell-derived factor 1 (SDF-1, CXCL12) is increased in subacromial bursitis and downregulated by steroid and nonsteroidal anti-inflammatory agents.
Science.gov (United States)
Kim, Yang-Soo; Bigliani, Louis U; Fujisawa, Motoyuki; Murakami, Koko; Chang, Seong-Sil; Lee, Hahn-Jun; Lee, Francis Y; Blaine, Theodore A
2006-08-01
Several studies have demonstrated that inflammation in the subacromial bursa is an important component in the pathogenesis of impingement syndrome. We have demonstrated in a previous study that many inflammatory cytokines, including stromal cell-derived factor 1 (SDF-1, CXCL12), are increased in the subacromial bursa [Blaine et al. 2005. J Shoulder Elbow Surg 14(Suppl 1):84S-89S]. SDF-1 is a potent chemotactic and angiogenic factor that stimulates recruitment of inflammatory cells. In the current study, we proposed that the resident cells in subacromial bursal tissue produce SDF-1, which can play a role in the inflammatory reponse of bursal tissue, and that this chemokine can be regulated by steroid (dexamethasone) and nonsteroidal anti-inflammatory medications (NSAIDs). Twenty-two subacromial bursa tissues (18 bursitis and 4 normal bursa) were obtained intraoperatively from patients during shoulder surgery and analyzed using the cDNA Array technique in accordance with an IRB approved protocol. cDNA array results were confirmed with real-time reverse transcription-polymerase chain reaction (RT-PCR). Bursal cells (from 4 normal bursa, 3 bursitis) and two normal bone marrow with whole tissue explants were cultured for one passage. Cell culture supernatants were collected and SDF-1 protein was detected with enzyme-linked immunosorbent assay (ELISA). Cultured bursal cells were treated with a COX-2 inhibitor and dexamethasone, and cells was harvested at 1-day and 4-day intervals. SDF-1 expression was evaluated by real-time RT-PCR and ELISA. cDNA Array analysis demonstrated that the gene expression of SDF-1 was increased in patients with subacromial bursitis compared to controls (p bursitis tissue is increased 10-fold over control tissue. While the normal bursal cells produced negligible amounts of SDF-1 protein, cultured cells derived from bursitis lesion released as much SDF-1 protein (235 pg/100,000 cells) as normal bone marrow stromal cells (283 pg/100,000 cells) as
20. Diagnostic performance of susceptibility-weighted magnetic resonance imaging for the assessment of sub-coracoacromial spurs causing subacromial impingement syndrome.
Science.gov (United States)
Nörenberg, Dominik; Armbruster, Marco; Bender, Yi-Na; Walter, Thula; Ebersberger, Hans U; Diederichs, Gerd; Hamm, Bernd; Ockert, Ben; Makowski, Marcus R
2017-03-01
To evaluate the potential of susceptibility-weighted-magnetic-resonance-imaging (SWMR) for the detection of sub-coracoacromial spurs in patients with clinically suspected subacromial impingement syndrome (SAIS), compared to standard MR-sequences and radiographs. Forty-four patients with suspected SAIS were included. All patients underwent radiography, standard MRI of the shoulder and SWMR. Radiograph-based identification of sub-coracoacromial spurs served as goldstandard. Radiographs identified twenty-three spurs in twenty-three patients. Twenty-one patients without spur formation served as reference group. Detection rate, sensitivity/specificity and interobserver-agreements were calculated. Linear regression was applied to determine the relationship between size measurements on radiographs and MRI. Detection rates for spurs on standard MRI and SWMR were 47.8 % and 91.3 % compared to radiography (pStandard MR-sequences achieved a sensitivity of 47.8 % (CI=0.185-0.775) and a specificity of 80.8 % (CI=0.642-0.978). Size measurements between SWMR and radiography showed a good correlation (R2=0.75;pstandard MRI (R2=0.24;psuperior to standard MR-sequences using radiography as goldstandard. • SWMR has the potential to reliably identify sub-coracoacromial spurs without radiation exposure. • SWMR provides comparable detection rates to conventional radiography for sub-coracoacromial spur formation. • SWMR yields higher detection rates compared to standard-MR regarding sub-coracoacromial spur formation. • SWMR can be implemented in routine shoulder MRI protocols.
1. One-year outcome of subacromial corticosteroid injection compared with manual physical therapy for the management of the unilateral shoulder impingement syndrome: a pragmatic randomized trial.
Science.gov (United States)
Rhon, Daniel I; Boyles, Robert B; Cleland, Joshua A
2014-08-05
Corticosteroid injections (CSIs) and physical therapy are used to treat patients with the shoulder impingement syndrome (SIS) but have never been directly compared. To compare the effectiveness of 2 common nonsurgical treatments for SIS. Randomized, single-blind, comparative-effectiveness, parallel-group trial. (ClinicalTrials.gov: NCT01190891). Military hospital-based outpatient clinic in the United States. 104 patients aged 18 to 65 years with unilateral SIS between June 2010 and March 2012. Random assignment into 2 groups: 40-mg triamcinolone acetonide subacromial CSI versus 6 sessions of manual physical therapy. The primary outcome was change in Shoulder Pain and Disability Index scores at 1 year. Secondary outcomes included the Global Rating of Change scores, the Numeric Pain Rating Scale scores, and 1-year health care use. Both groups demonstrated approximately 50% improvement in Shoulder Pain and Disability Index scores maintained through 1 year; however, the mean difference between groups was not significant (1.5% [95% CI, -6.3% to 9.4%]). Both groups showed improvements in Global Rating of Change scale and pain rating scores, but between-group differences in scores for the Global Rating of Change scale (0 [CI, -2 to 1]) and pain rating (0.4 [CI, -0.5 to 1.2]) were not significant. During the 1-year follow-up, patients receiving CSI had more SIS-related visits to their primary care provider (60% vs. 37%) and required additional steroid injections (38% vs. 20%), and 19% needed physical therapy. Transient pain from the CSI was the only adverse event reported. The study occurred at 1 center with patients referred to physical therapy. Both groups experienced significant improvement. The manual physical therapy group used less 1-year SIS-related health care resources than the CSI group. Cardon Rehabilitation Products through the American Academy of Orthopaedic Manual Physical Therapists.
2. Risk of surgery for subacromial impingement syndrome in relation to neck-shoulder complaints and occupational biomechanical exposures: a longitudinal study.
Science.gov (United States)
Svendsen, Susanne Wulff; Dalbøge, Annett; Andersen, Johan Hviid; Thomsen, Jane Frølund; Frost, Poul
2013-11-01
3. Diagnostic performance of susceptibility-weighted magnetic resonance imaging for the assessment of sub-coracoacromial spurs causing subacromial impingement syndrome
Energy Technology Data Exchange (ETDEWEB)
Noerenberg, Dominik; Armbruster, Marco [Munich University Hospitals Campus Grosshadern, Department of Clinical Radiology, Munich (Germany); Bender, Yi-Na; Walter, Thula; Diederichs, Gerd; Hamm, Bernd [Charite - University Medicine Berlin, Department of Radiology, Berlin (Germany); Ebersberger, Hans U. [Heart Center Munich-Bogenhausen, Department of Cardiology and Intensive Care Medicine, Munich (Germany); Ockert, Ben [Munich University Hospitals Campus Grosshadern, Department of Trauma and Orthopedic Surgery, Shoulder and Elbow Service, Munich (Germany); Makowski, Marcus R. [Charite - University Medicine Berlin, Department of Radiology, Berlin (Germany); King' s College London, Division of Imaging Sciences and Biomedical Engineering, London (United Kingdom)
2017-03-15
To evaluate the potential of susceptibility-weighted-magnetic-resonance-imaging (SWMR) for the detection of sub-coracoacromial spurs in patients with clinically suspected subacromial impingement syndrome (SAIS), compared to standard MR-sequences and radiographs. Forty-four patients with suspected SAIS were included. All patients underwent radiography, standard MRI of the shoulder and SWMR. Radiograph-based identification of sub-coracoacromial spurs served as goldstandard. Radiographs identified twenty-three spurs in twenty-three patients. Twenty-one patients without spur formation served as reference group. Detection rate, sensitivity/specificity and interobserver-agreements were calculated. Linear regression was applied to determine the relationship between size measurements on radiographs and MRI. Detection rates for spurs on standard MRI and SWMR were 47.8 % and 91.3 % compared to radiography (p<0.001). SWMR demonstrated a sensitivity of 97.7 % (CI=0.92-1) and a specificity of 91.3 % (CI=0.788-1) for the identification of spurs. Standard MR-sequences achieved a sensitivity of 47.8 % (CI=0.185-0.775) and a specificity of 80.8 % (CI=0.642-0.978). Size measurements between SWMR and radiography showed a good correlation (R{sup 2}=0.75;p<0.0001), while overestimating lesion size (5.7±1.2 mm; 4.3±1.3 mm;p<0.0001). Interobserver-agreement for spurs was high on SWMR (R{sup 2}=0.74;p<0.0001), but low on standard MRI (R{sup 2}=0.24;p<0.0001). SWMR allows a reliable detection of sub-coracoacromial spur formation in patients with SAIS and is superior to standard MR-sequences using radiography as goldstandard. (orig.)
4. Magnetic resonance imaging of rotator cuff tears in shoulder impingement syndrome.
Science.gov (United States)
Freygant, Magdalena; Dziurzyńska-Białek, Ewa; Guz, Wiesław; Samojedny, Antoni; Gołofit, Andrzej; Kostkiewicz, Agnieszka; Terpin, Krzysztof
2014-01-01
Shoulder joint is a common site of musculoskeletal pain caused, among other things, by rotator cuff tears due to narrowing of subacromial space, acute trauma or chronic shoulder overload. Magnetic resonance imaging (MRI) is an excellent modality for imaging of soft tissues of the shoulder joint considering a possibility of multiplanar image acquisition and non-invasive nature of the study. The aim of this study was to evaluate the prevalence of partial and complete rotator cuff tears in magnetic resonance images of patients with shoulder impingement syndrome and to review the literature on the causes and classification of rotator cuff tears. We retrospectively analyzed the results of 137 shoulder MRI examinations performed in 57 women and 72 men in Magnetic Resonance facility of the Department of Radiology and Diagnostic Imaging at the St. Jadwiga the Queen Regional Hospital No. 2 in Rzeszow between June 2010 and February 2013. Examinations were performed using Philips Achieva 1.5T device, including spin echo and gradient echo sequences with T1-, T2- and PD-weighted as well as fat saturation sequences in transverse, frontal and sagittal oblique planes. Patients were referred from hospital wards as well as from outpatient clinics of the subcarpathian province. The most frequently reported injuries included partial supraspinatus tendon tear and complete tearing most commonly involved the supraspinatus muscle tendon. The smallest group comprised patients with complete tear of subscapularis muscle tendon. Among 137 patients in the study population, 129 patients suffered from shoulder pain, including 57 patients who reported a history of trauma. There was 44% women and 56% men in a group of patients with shoulder pain. Posttraumatic shoulder pain was predominantly reported by men, while women comprised a larger group of patients with shoulder pain not preceded by injury. Rotator cuff injury is a very common pathology in patients with shoulder impingement syndrome
5. Efficacy and safety of a subacromial continuous ropivacaine infusion for post-operative pain management following arthroscopic rotator cuff surgery: A protocol for a randomised double-blind placebo-controlled trial
Directory of Open Access Journals (Sweden)
Bell Simon N
2008-04-01
Full Text Available Abstract Background Major shoulder surgery often results in severe post-operative pain and a variety of interventions have been developed in an attempt to address this. The continuous slow infusion of a local anaesthetic directly into the operative site has recently gained popularity but it is expensive and as yet there is little conclusive evidence that it provides additional benefits over other methods of post-operative pain management. Methods/Design This will be a randomised, placebo-controlled trial involving 158 participants. Following diagnostic arthroscopy, all participants will undergo arthroscopic subacromial decompression with or without rotator cuff repair, all operations performed by a single surgeon. Participants, the surgeon, nurses caring for the patients and outcome assessors will be blinded to treatment allocation. All participants will receive a pre-incision bolus injection of 20 mls of ropivacaine 1% into the shoulder and an intra-operative intravenous bolus of parecoxib 40 mg. Using concealed allocation participants will be randomly assigned to active treatment (local anaesthetic ropivacaine 0.75% or placebo (normal saline administered continuously into the subacromial space by an elastomeric pump at 5 mls per hour post-operatively. Patient controlled opioid analgesia and oral analgesics will be available for breakthrough pain. Outcome assessment will be at 15, 30 and 60 minutes, 2, 4, 8, 12, 18 and 24 hours, and 2 or 4 months for decompression or decompression plus repair respectively. The primary end point will be average pain at rest over the first 12-hour post-operative period on a verbal analogue pain score. Secondary end points will be average pain at rest over the second 12-hour post-operative period, maximal pain at rest over the first and second 12-hour periods, amount of rescue medication used, length of inpatient stay and incidence of post-operative adhesive capsulitis. Discussion The results of this trial will
6. Exercises versus arthroscopic decompression in patients with subacromial impingement: a randomised, controlled study in 90 cases with a one year follow up
DEFF Research Database (Denmark)
Haahr, J. P.; Ostergaard, S.; Dalsgaard, J.
2005-01-01
OBJECTIVES: To compare the effect of graded physiotherapeutic training of the rotator cuff versus arthroscopic subacromial decompression in patients with subacromial impingement. METHODS: Randomised controlled trial with 12 months' follow up in a hospital setting. Ninety consecutive patients aged...... 18 to 55 years were enrolled. Symptom duration was between six months and three years. All fulfilled a set of diagnostic criteria for rotator cuff disease, including a positive impingement sign. Patients were randomised either to arthroscopic subacromial decompression, or to physiotherapy...
7. "Pinching subacromial problems” - A clinical and biomechanical approach -
NARCIS (Netherlands)
Witte, Pieter Bas de
2015-01-01
The Subacromial Impingement Syndrome (SIS) is the most prevalent disorder of the shoulder in primary health care. Acromionplasty, as the main surgical treatment of SIS, is one of the most performed orthopedic surgeries. However, its results are highly variable. Possibly, there are different
8. Surgery for subacromial impingement syndrome in relation to occupational exposures, lifestyle factors and diabetes mellitus: a nationwide nested case-control study.
Science.gov (United States)
Dalbøge, Annett; Frost, Poul; Andersen, Johan Hviid; Svendsen, Susanne Wulff
2017-10-01
9. Shoulder Retractor Strengthening Exercise to Minimize Rhomboid Muscle Activity and Subacromial Impingement
Science.gov (United States)
Fennell, Jeremy; Mochizuki, George; Ismail, Farooq; Boulias, Chris
2016-01-01
Purpose: We investigated the best position for shoulder retractor strengthening exercise to maximize middle trapezius activity and minimize rhomboid major activity. Although both trapezius and rhomboids are scapular retractors, rhomboids also act as downward rotators of the scapula, which can worsen subacromial impingement. Methods: Twelve healthy participants (age 30 [SD 6] y) with no history of shoulder pain were recruited for this study, which used fine-wire electromyography to examine maximal muscle activation of the middle trapezius and rhomboid major muscle fibres in four different positions: with the shoulder in 90° abduction with elbow completely extended and (1) shoulder internal rotation, (2) shoulder neutral rotation, (3) shoulder external rotation, and (4) rowing (shoulder neutral rotation and elbow flexed 90°). The ratio of trapezius to rhomboid muscles was compared with Wilcoxon signed-rank tests. Results: Muscle activation ratio during shoulder retraction exercise was significantly lower by 22% (i.e., rhomboid was more active than middle trapezius) when performed with the shoulder in rowing position (elbow flexed) than with the shoulder in external rotation (elbow extended) position (p=0.031). All four positions produced coactivation of trapezius and rhomboids. Discussion: Rowing position may not be the best position for shoulder retractor strengthening in patients with impingement syndrome. The preferable position for maximizing middle trapezius activity and minimizing rhomboid activity may be shoulder external rotation with elbow extended. PMID:27504044
10. Synovial osteochondromatosis in the subacromial bursa mimicking calcific tendinitis: sonographic diagnosis.
Science.gov (United States)
Kim, Tae-Kwon; Lee, Dae-Hee; Park, Jong-Hoon; Kim, Chul-Hwan; Jeong, Woong-Kyo
2014-05-01
Synovial osteochondromatosis is an idiopathic benign metaplasia of the synovial membrane rarely found in an extra-articular bursa. We describe the case of a 55-year-old woman with synovial osteochondromatosis in the subacromial bursa mimicking calcific tendinitis. Plain radiographs showed a radiopaque mass over the middle facet of the greater tuberosity, suggesting calcific tendinitis. Sonography, however, showed a loose body in the subacromial bursa, and no evidence of calcification inside the rotator cuff. Copyright © 2013 Wiley Periodicals, Inc.
11. Differences in scapular orientation, subacromial space and shoulder pain between the full can and empty can tests.
Science.gov (United States)
Timmons, Mark K; Lopes-Albers, Andrea Diniz; Borgsmiller, Lindsey; Zirker, Catherine; Ericksen, Jeff; Michener, Lori A
2013-04-01
The empty and full can arm positions are used as diagnostic tests and in therapeutic exercise programs for patients with subacromial impingement syndrome. The adverse effects of these arm positions on the rotator cuff have not been fully described. The purpose of this investigation was to compare the acromio-humeral distance, three-dimensional scapular position, and shoulder pain during maximum isometric contractions in the empty and full can arm positions. Subjects with subacromial impingement syndrome (n=28) and a matched control group without shoulder pain (n=28) participated. Acromio-humeral distance, scapular/clavicular positions and shoulder pain were measured during maximal isometric contractions in each position. No difference was found in acromio-humeral distance (P=0.314) between the arm positions or between the groups (P=0.598). The empty can position resulted in greater scapular upward rotation (Ppain in the EC position might be due to the lack of an association amongst the scapular positions rather than the deficiency of a single scapular motion. Published by Elsevier Ltd.
12. Which shoulder motions cause subacromial impingement? Evaluating the vertical displacement and peak strain of the coracoacromial ligament by ultrasound speckle tracking imaging.
Science.gov (United States)
Park, In; Lee, Hyo-Jin; Kim, Sung-Eun; Bae, Sung-Ho; Byun, Chu-Hwan; Kim, Yang-Soo
2015-11-01
Subacromial impingement is a common cause of shoulder pain and one cause of rotator cuff disease. We aimed to identify which shoulder motions cause subacromial impingement by measuring the vertical displacement and peak strain of the coracoacromial ligament using ultrasound speckle tracking imaging. Sixteen shoulders without shoulder disability were enrolled. All subjects were men, and the average age was 28.6 years. The vertical displacement and peak strain of the coracoacromial ligament were analyzed by the motion tracing program during the following active assisted motions (active motion controlled by the examiner): (1) forward flexion in the scapular plane, (2) horizontal abduction in the axial plane, (3) external rotation with the arm at 0° abduction (ER0), (4) internal rotation with the arm at 0° abduction (IR0), (5) internal rotation with the arm at 90° abduction (IR90), and (6) internal rotation at the back (IRB). The mean vertical displacement of the coracoacromial ligament during forward flexion (2.2 mm), horizontal abduction (2.2 mm), and IR90 (2.4 mm) was significantly greater than that during the other motions (ER0, -0.7 mm; IR0, 0.5 mm; IRB, 1.0 mm; P impingement. It is recommended that patients with impingement syndrome or a repaired rotator cuff avoid these shoulder motions. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
13. Heterotaxy syndromes and abnormal bowel rotation
Energy Technology Data Exchange (ETDEWEB)
Newman, Beverley [Stanford University, Lucile Packard Children' s Hospital, Department of Radiology, Stanford, CA (United States); Koppolu, Raji; Sylvester, Karl [Lucile Packard Children' s Hospital at Stanford, Department of Surgery, Stanford, CA (United States); Murphy, Daniel [Lucile Packard Children' s Hospital at Stanford, Department of Cardiology, Stanford, CA (United States)
2014-05-15
Bowel rotation abnormalities in heterotaxy are common. As more children survive cardiac surgery, the management of gastrointestinal abnormalities has become controversial. To evaluate imaging of malrotation in heterotaxy with surgical correlation and provide an algorithm for management. Imaging reports of heterotaxic children with upper gastrointestinal (UGI) and/or small bowel follow-through (SBFT) were reviewed. Subsequently, fluoroscopic images were re-reviewed in conjunction with CT/MR studies. The original reports and re-reviewed images were compared and correlated with surgical findings. Nineteen of 34 children with heterotaxy underwent UGI, 13/19 also had SBFT. In 15/19 reports, bowel rotation was called abnormal: 11 malrotation, 4 non-rotation, no cases of volvulus. Re-review, including CT (10/19) and MR (2/19), designated 17/19 (90%) as abnormal, 10 malrotation (abnormal bowel arrangement, narrow or uncertain length of mesentery) and 7 non-rotation (small bowel and colon on opposite sides plus low cecum with probable broad mesentery). The most useful CT/MR findings were absence of retroperitoneal duodenum in most abnormal cases and location of bowel, especially cecum. Abnormal orientation of mesenteric vessels suggested malrotation but was not universal. Nine children had elective bowel surgery; non-rotation was found in 4/9 and malrotation was found in 5/9, with discrepancies (non-rotation at surgery, malrotation on imaging) with 4 original interpretations and 1 re-review. We recommend routine, early UGI and SBFT studies once other, urgent clinical concerns have been stabilized, with elective laparoscopic surgery in abnormal or equivocal cases. Cross-sectional imaging, usually obtained for other reasons, can contribute diagnostically. Attempting to assess mesenteric width is important in differentiating non-rotation from malrotation and more accurately identifies appropriate surgical candidates. (orig.)
14. Interleukin-1β stimulates stromal-derived factor-1α expression in human subacromial bursa.
Science.gov (United States)
Blaine, Theodore A; Cote, Mindy A; Proto, Al; Mulcahey, Mary; Lee, Francis Y; Bigliani, Louis U
2011-11-01
Chemokines produced by synoviocytes of the subacromial bursa are up-regulated in subacromial bursitis and rotator cuff disease. We hypothesized that SDF-1α production in bursal synoviocytes may be induced by local cytokines such as interleukin IL-1β and IL-6. Subacromial bursa specimens were obtained from patients undergoing shoulder surgery. Bursal specimens were stained with anti-human antibodies to IL-1, IL-6, and SDF-1α by immunohistochemistry and compared to normal and rheumatoid controls. Bursal cells were also isolated from specimens and cultured. Early passaged cells were then treated with cytokines (IL-1β and IL-6) and SDF-1α expression was measured by ELISA and RT-PCR. SDF-1α, IL-1β, and IL-6 were expressed at high levels in bursitis specimens from human subacromial bursa compared to normal controls. In cultured bursal synoviocytes, there was a dose-dependent increase in SDF-1α production in the supernatants of cells treated with IL-1β. SDF-1α mRNA expression was also increased in bursal cells treated with IL-1β. IL-6 caused a minimal but not statistically significant increase in SDF-1α expression. SDF-1α, IL-1β, and IL-6 are expressed in the inflamed human subacromial bursal tissues in patients with subacromial bursitis. In cultured bursal synoviocytes, SDF-1α gene expression and protein production are stimulated by IL-1β. IL-1β produced by bursal syvoviocytes and inflammatory cells in the human subacromial bursa is an important signal in the inflammatory response that occurs in subacromial bursitis and rotator cuff disease. Copyright © 2011 Orthopaedic Research Society.
15. Spontaneous Isolated Infection of the Subacromial Bursa
Science.gov (United States)
Al-Tawil, Karam
2013-01-01
Isolated infection of the subacromial bursa is a rare entity. We present the case of a previously fit man who was found to have staphylococcal infection of the sub-acromial bursa, without an obvious precipitant. Preoperative MRI scanning determined the specific locus of infection, and the patient was successfully treated with arthroscopic washout of the sub-acromial bursa followed by empirical antibiotic therapy. PMID:23984140
16. Rotator cuff related shoulder pain: Assessment, management and uncertainties.
Science.gov (United States)
Lewis, Jeremy
2016-06-01
Rotator cuff related shoulder pain (RCRSP) is an over-arching term that encompasses a spectrum of shoulder conditions including; subacromial pain (impingement) syndrome, rotator cuff tendinopathy, and symptomatic partial and full thickness rotator cuff tears. For those diagnosed with RCRSP one aim of treatment is to achieve symptom free shoulder movement and function. Findings from published high quality research investigations suggest that a graduated and well-constructed exercise approach confers at least equivalent benefit as that derived from surgery for; subacromial pain (impingement) syndrome, rotator cuff tendinopathy, partial thickness rotator cuff (RC) tears and atraumatic full thickness rotator cuff tears. However considerable deficits in our understanding of RCRSP persist. These include; (i) cause and source of symptoms, (ii) establishing a definitive diagnosis, (iii) establishing the epidemiology of symptomatic RCRSP, (iv) knowing which tissues or systems to target intervention, and (v) which interventions are most effective. The aim of this masterclass is to address a number of these areas of uncertainty and it will focus on; (i) RC function, (ii) symptoms, (iii) aetiology, (iv) assessment and management, (v) imaging, and (vi) uncertainties associated with surgery. Although people experiencing RCRSP should derive considerable confidence that exercise therapy is associated with successful outcomes that are comparable to surgery, outcomes may be incomplete and associated with persisting and recurring symptoms. This underpins the need for ongoing research to; better understand the aetiology, improve methods of assessment and management, and eventually prevent these conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.
17. Is Ultrasound-Guided Injection More Effective in Chronic Subacromial Bursitis?
National Research Council Canada - National Science Library
HSIEH, LIN-FEN; HSU, WEI-CHUN; LIN, YI-JIA; WU, SHIH-HUI; CHANG, KAE-CHWEN; CHANG, HSIAO-LAN
2013-01-01
.... Therefore, this study aimed to compare the efficacy of subacromial corticosteroid injection under US guidance with palpation-guided subacromial injection in patients with chronic subacromial bursitis...
18. Arthroscopic Finding of an Extra-Articular Loose Body in the Subacromial Space: Case Report Presentation and Literature Review.
Science.gov (United States)
Hartelius, Carl; Apostolopoulos, Alexandros P; Zaman, Tariq
2016-01-01
Loose bodies are pieces of soft tissue that run free within a body cavity, typically in the synovium; loose bodies outside of synovial cavities are very rare. This case study demonstrates such an instance occurring in the subacromial space, which is especially unusual. We report on it coupled with an analysis of the literature of known cases that have occurred previously. A 55-year old right-hand-dominant female patient presented with left shoulder pain. She had injured her left shoulder 7 yr previously and had achieved adequate pain and symptomatic control with physiotherapy. A magnetic resonance imaging scan demonstrated subacromial subdeltoid bursitis with a large subacromial spur, a bulky acromioclavicular (AC) joint, and a partial tear of the supraspinatous tendon. The patient subsequently underwent shoulder arthroscopy for subacromial decompression and AC joint excision. Arthroscopy demonstrated a suspected impingement of the rotator cuff in the subacromial space, bursitis, and a prominent acromion that limited the subacromial space (bigliani, type III), but during the procedure a detached white mass was discovered in the subacromial bursa. After histological analysis, the mass showed osteocartilagenous tissue, consistent with a loose body. Following the procedure, there were no complications, and the patient's symptoms gradually resolved. Extraarticular loose bodies are extremely rare, especially in the subacromial bursa. Reported cases have all been associated with either traumatic or degenerative shoulder pathology, and the diagnosis was commonly established incidentally on arthroscopy. Cases were managed with removal during the same procedure. Arthroscopic removal of loose bodies and bursa debridement, good options for treatment of loose bodies in the subacromial space, can result in good function.
19. Rotating shift work and the metabolic syndrome: a prospective study.
Science.gov (United States)
De Bacquer, D; Van Risseghem, M; Clays, E; Kittel, F; De Backer, G; Braeckman, L
2009-06-01
Several studies have documented on the elevated cardiovascular risk among shift workers. In order to further explore this relation, we aimed at assessing the association between rotating shift work and the incidence of the metabolic syndrome (MetS). In this population-based prospective study, 1529 employees from several large Belgian companies were followed for a median observation period of 6.6 years with respect to the onset of the MetS and its separate components. At baseline, 309 men (20.2%) were rotating shift workers. The MetS incidence rate in these shift workers (60.6 per 1000 person-years) was increased in comparison with day workers (37.2 per 1000 person-years) with an odds ratio (95% CI) of 1.77 (1.34-2.32). Multivariate adjustment for potential lifestyle and work-related confounders did only marginally affect the strength of the association. The risk for the development of MetS gradually increased independently with accumulated years of shift work. Rotating shift work not only had an impact on MetS as a cluster of conditions but on each of its individual components as well. Hence, prospective evidence was found that rotating shift work increases the risk for developing the MetS over a period of 6 years.
20. Arthroscopic subacromial decompression results in normal shoulder function after two years in less than 50% of patients
DEFF Research Database (Denmark)
Konradsen, Lars Aage Glud; Jensen, Claus Hjorth
2015-01-01
INTRODUCTION: The aim of this study was to evaluate the outcome two years after arthroscopic subacromial decompression using the Western Ontario Rotator-Cuff (WORC) index and a diagram-based questionnaire to self-assess active shoulder range of motion (ROM). METHODS: Outcomes in 80 patients...... with impingement of the shoulder undergoing arthroscopic subacromial decompression were prospectively assessed preoperatively, at three months and at two years post-operatively using the WORC index. All patients had received non-operative treatment for at least six months before undergoing surgery. Active range......, but only 45% reported near normal or normal WORC scores, and 56% presented with a reduced active ROM at two years. CONCLUSION: Arthroscopic subacromial decompression -appears effective in alleviating symptoms in patients with subacromial impingement who are resistant to conservative treatment, but can only...
1. Lipoma arborescens: caso raro de ruptura do manguito rotador associado à presença de lipoma arborescens na bursa subacromial-subdeltoidea e glenoumeral Lipoma arborescens: rare case of rotator cuff tear associated with the presence of lipoma arborescens in the subacromial-subdeltoid and glenohumeral bursa
Directory of Open Access Journals (Sweden)
Eduardo Benegas
2012-01-01
Full Text Available Lipoma arborescens é uma condição rara de moléstia intra-articular, usualmente monoarticular, caracterizada por extensa proliferação dos vilos sinoviais e hiperplasia da gordura subsinovial. O tecido sinovial é progressivamente substituído por células maduras de gordura na membrana sinovial. O presente trabalho é o relato de caso de uma condição rara de lipoma arborescens tanto intra-articular (glenoumeral como da bursa subacromial-subdeltoide além de ruptura do tendão do supraespinhoso. As apresentações clínicas, histológicas e radiográficas assim como o tratamento são discutidos no presente estudo. A apresentação do caso contempla também a avaliação radiográfica, ressonância magnética e exame patológico. Apesar do lipoma arborescens ser uma condição rara, tal hipótese deve ser considerada frente a um caso com hiperproliferação sinovial e lipossubstituição da sinovial.Lipoma arborescens is a rare intra-articular disease that is usually monoarticular and is characterized by extensive proliferation of the synovial villi and hyperplasia of the subsynovial fat. The synovial tissue is progressively replaced by mature fat cells in the synovial membrane. The present study reports a case of a rare condition of lipoma arborescens that was simultaneously intra-articular (glenohumeral joint and in the subacromial-subdeltoid bursa, in association with a torn supraspinatus tendon. The clinical, histological and radiographic presentations and treatment are discussed here. The description of this case includes radiographic and magnetic resonance evaluations and pathological examination. Although lipoma arborescens is a rare condition, it should be taken into consideration in cases presenting synovial hyperproliferation and synovial fat replacement.
2. Distances to the subacromial bursa from 3 different injection sites as measured arthroscopically.
Science.gov (United States)
Sardelli, Matthew; Burks, Robert T
2008-09-01
The purpose of this study was to assess the distance for a standard needle to reach the subacromial bursa through 3 commonly used approaches. Thirty patients without associated rotator cuff tears underwent arthroscopic evaluation of the shoulder. The bursa was entered without shaving or altering of the bursa. By use of standard arthroscopic portals, a spinal needle was inserted from an anterior, lateral, and posterior position and measured to define the distance to the subacromial bursa from the skin. The mean distance with anterior needle placement was 2.9 +/- 0.6 cm. The mean distance with lateral needle placement was 2.9 +/- 0.7 cm. The mean distance with posterior needle placement was 5.2 +/- 1.1 cm. The mean body mass index for the group of patients was 27.5. The minimum was 18.7, and the maximum was 42.8. The distance to the subacromial bursa from the anterior and lateral approaches appears to be consistent and within reach of a standard 22- or 25-gauge needle. The distance to the subacromial bursa from a posterior approach appears to be almost double that of the anterior and lateral approaches and may not be reachable by standard 22- and 25-gauge needles in all patients. There appears to be no correlation between distances to the subacromial bursa from the anterior, lateral, or posterior approaches and the patient's body mass index. Given the relative distances measured to the subacromial bursa from the anterior, lateral, and posterior positions, clinicians may choose a longer needle to improve the accuracy of placement when approaching the subacromial bursa from a posterior position. Use of a standard-length needle will provide reasonable accuracy from the anterior and lateral positions.
3. Glenohumeral and scapulothoracic strength impairments exists in patients with subacromial impingement, but these are not reflected in the shoulder pain and disability index
DEFF Research Database (Denmark)
Clausen, M B; Witten, A; Holm, K
2017-01-01
BACKGROUND: Pain and loss of function are cardinal symptoms associated with Subacromial impingement syndrome (SIS), while the presence and magnitude of deficits in strength and range of motion (ROM) are largely undescribed in non-athletic patients with SIS. Moreover, the relevance of impairments...... diagnostic criteria. Prior to specialist examination, questionnaires regarding shoulder function (Shoulder Pain And Disability Index, SPADI) demographics and kinesiophobia (TSK-11) were collected, and shoulder strength and ROM was measured by trained testers, with the patient reporting pain levels during...... testing and for the last week. Impairments in strength (abduction, external-rotation, (protraction and horizontal-extension) and ROM (abduction and internal rotation) were investigated in patients with unilateral shoulder pain, using one-sample t-tests. SPADI total score (SPADI) and SPADI function score...
4. Arthroscopic Resection of The Distal Clavicle With Concomitant Subacromial Decompression: A Case Series
Directory of Open Access Journals (Sweden)
HZ Chan
2014-07-01
Full Text Available Shoulder impingement syndrome and acromioclavicular joint osteoarthritis often occur simultaneously and easily missed. Kay et al. reported excellent results with combined arthroscopic subacromial decompression and resection of the distal end of the clavicle in patients with both disorders. Arthroscopic treatment of these disorders produces more favourable results than open procedures. We report two patients who were not responding to conservative management and were treated with direct arthroscopic distal clavicle excision and subacromial decompression in single setting. Both patients gained good postoperative outcome in terms of pain score, function and strength improvement assessed objectively with visual analogue score (VAS and University of California Los Angeles Score (UCLA.
5. The effect of experimentally-induced subacromial pain on proprioception.
Science.gov (United States)
Sole, Gisela; Osborne, Hamish; Wassinger, Craig
2015-02-01
Shoulder injuries may be associated with proprioceptive deficits, however, it is unknown whether these changes are due to the experience of pain, tissue damage, or a combination of these. The aim of this study was to investigate the effect of experimentally-induced sub-acromial pain on proprioceptive variables. Sub-acromial pain was induced via hypertonic saline injection in 20 healthy participants. Passive joint replication (PJR) and threshold to detection of movement direction (TTDMD) were assessed with a Biodex System 3 Pro isokinetic dynamometer for baseline control, experimental pain and recovery control conditions with a starting position of 60° shoulder abduction. The target angle for PJR was 60° external rotation, starting from 40°. TTDMD was tested from a position of 20° external rotation. Repeated measures ANOVAs were used to determine differences between PJR absolute and variable errors and TTDMD for the control and experimental conditions. Pain was elicited with a median 7 on the Numeric Pain Rating Scale. TTDMD was significantly decreased for the experimental pain condition compared to baseline and recovery conditions (≈30%, P = 0.003). No significant differences were found for absolute (P = 0.152) and variable (P = 0.514) error for PJR. Movement sense was enhanced for the experimental sub-acromial pain condition, which may reflect protective effects of the central nervous system in response to the pain. Where decreased passive proprioception is observed in shoulders with injuries, these may be due to a combination of peripheral tissue injury and neural adaptations that differ from those due to acute pain. Copyright © 2014 Elsevier Ltd. All rights reserved.
6. Shoulder internal rotation elbow flexion test for diagnosing cubital tunnel syndrome.
Science.gov (United States)
Ochi, Kensuke; Horiuchi, Yukio; Tanabe, Aya; Waseda, Makoto; Kaneko, Yasuhito; Koyanagi, Takahiro
2012-06-01
Shoulder internal rotation enhances symptom provocation attributed to cubital tunnel syndrome. We present a modified elbow flexion test--the shoulder internal rotation elbow flexion test--for diagnosing cubital tunnel syndrome. Fifty-five ulnar nerves in cubital tunnel syndrome patients and 123 ulnar nerves in controls were examined with 5 seconds each of elbow flexion, shoulder internal rotation, and shoulder internal rotation elbow flexion tests before and after treatment (surgery in 18; conservative in others). For the shoulder internal rotation elbow flexion test position, 90° abduction, maximum internal rotation, and 10° flexion of the shoulder were combined with the elbow flexion test position. The test was considered positive if any symptom for cubital tunnel syndrome developed cubital tunnel syndrome nerves and 7 control nerves. The sensitivities/specificities of the 5-second elbow flexion, shoulder internal rotation, and shoulder internal rotation elbow flexion tests were 25%/100%, 58%/100%, and 87%/98%, respectively. Sensitivity differences between the shoulder internal rotation elbow flexion test and the other two tests were significant. Shoulder internal rotation elbow flexion test results and cubital tunnel syndrome symptoms were significantly correlated. Influence of the shoulder internal rotation elbow flexion test on the ulnar nerve was seen in 8 of 10 cubital tunnel syndrome nerves but not in controls. The 5-second shoulder internal rotation elbow flexion test is specific, easy and quick provocative test for diagnosing cubital tunnel syndrome. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.
7. Subacromial shoulder disorders among baggage handlers
DEFF Research Database (Denmark)
Thygesen, Lau Caspar; Mikkelsen, Sigurd; Pedersen, Ellen Bøtker
2016-01-01
PURPOSE: To assess the influence of cumulative employment as baggage handler on the risk of incident subacromial shoulder disorders. Baggage handling is characterized by repetitive work primarily consisting of heavy lifting in awkward positions and time pressure. METHODS: This cohort study is based...... System. The primary exposure was cumulative years of employment as a baggage handler, and the primary outcome was diagnoses and surgical treatment of subacromial shoulder disorders. RESULTS: The cohort contained 3396 baggage handlers and 63,909 workers in the reference group. Baggage handlers with longer...... increased incidence of subacromial shoulder disorders for workers with longer cumulative years of employment. These results support that long-term lifting in awkward positions and time pressure influences the risk of subacromial shoulder disorders....
8. Dynamic enhanced MRI of the subacromial bursa: correlation with arthroscopic and histological findings
Energy Technology Data Exchange (ETDEWEB)
Matsuzaki, S. [Dept. of Radiology, Osaka Kosei-nenkin Hospital (Japan); Yoneda, M. [Shoulder and Sports Medicine Service, Osaka Kosei-nenkin Hospital, Osaka City, Osaka (Japan); Kobayashi, Y. [Dept. of Pathology, Osaka Kosei-nenkin Hospital (Japan); Fukushima, S. [Dept. of Orthopaedic Surgery, Sapporo Tokeidai Hospital, Osaka (Japan); Wakitani, S. [Dept. of Orthopaedic Surgery, Shinsyu Univ., Matsumato (Japan)
2003-09-01
Objective: To assess dynamic MRI with Gd-DTPA enhancement for evaluating inflammatory changes in the subacromial bursa. Design and patients: We detected the signal intensity changes in dynamic MRI of the subacromial bursa, and confirmed these macroscopically by arthroscopy and histologically. The signal intensity was measured using built-in software, and the enhancement ratio (E ratio) was calculated from dynamic MR images. In addition, as a parameter of the rate of the increase in the signal intensity from 0 to 80 s, the mean increase per second in the E ratio was obtained as the coefficient of enhancement (CE). The correlation was studied of the E ratio and CE with the arthroscopic findings (redness, villous formation, thickening and adhesion), and of the E ratio and CE with the histological findings (capillary proliferation, papillary hyperplasia, fibrosis and inflammatory cell infiltration) of the subacromial bursa. Of patients with shoulder pain, this study included those with rotator cuff injury; patients with rheumatoid arthritis or pitching shoulder disorders were excluded. There were 27 patients (15 men, 12 women) ranging in age from 25 to 73 years (mean 49.1 years). Dynamic MRI of the shoulder was also performed on the healthy side of 10 patients and in five normal young volunteers. Results and conclusions: Changes in signal intensity on dynamic MRI were measured in the subacromial bursa. The E ratio (80 s) and CE (0-80 s) were significantly correlated with redness and villous formation as arthroscopic findings, positively correlated with capillary proliferation and papillary hyperplasia as histological findings (p < 0.05), and negatively correlated with fibrosis as a histological finding (p < 0.05) in the subacromial bursa. The patterns of dynamic curves were well correlated with the bursoscopic and histological findings of the synovium of the subacromial bursa. Dynamic MRI appears to correlate with inflammatory activity of synovium of the subacromial
9. MR imaging after therapeutic injection of the subacromial bursa
Energy Technology Data Exchange (ETDEWEB)
Major, N.M. [Duke University Medical Center, Department of Radiology, Division Musculoskeletal, Durham, NC (United States)
1999-11-01
Objective. As a therapeutic injection into the subacromial bursa (SAB) is commonly performed for impingement syndrome, it is important to know whether this fluid can be retained for a period of time and cause confusion with a pathologic collection of fluid. This study identifies and describes the appearance of recent subacromial injection using MR imaging, and the appearance of a potential complication.Design and patients. Fourteen asymptomatic shoulders were studied with MR imaging using fast spin echo T2-weighted imaging (1.5 T) prior to injection with 7 cm{sup 3} of xylocaine. Four shoulders had subacromial fluid and were eliminated from the study. The remaining 10 (9 men, 1 woman; age range 27-36 years, average age 33 years) were then re-imaged immediately, and at 6, 12 and 24 h after the injection or until fluid resolved. Each set of images was reviewed for the presence of fluid in the SAB and for additional abnormalities.Results. Fluid was identified in all subjects in the SAB in the immediate, 6 and 12 h post-injection images. At 24 h, fluid was not identified within the SAB in eight of 10 patients. In one patient fluid resolved in 48 h. The other continued to demonstrate fluid in the SAB and in the joint as well as abnormal signal in the infraspinatus muscle from a presumed myositis. Imaging was performed up to 10 days after the injection in this patient.Conclusions. It is known that fluid identified in the SAB without evidence of a cuff tear may be due to bursitis. However, if MR imaging is performed within 24 h of injection, the presence of the fluid may be iatrogenic. In addition, the history of recent therapeutic injection is very important as complications such as myositis can occur as a result of the injection. Knowledge of injection prior to imaging is vital for accurate interpretation of MR shoulder examinations. (orig.)
10. An analysis of the diagnostic accuracy of the Hawkins and Neer subacromial impingement signs.
Science.gov (United States)
MacDonald, P B; Clark, P; Sutherland, K
2000-01-01
The purpose of this study was to assess the diagnostic accuracy of the Neer and Hawkins impingement signs for the diagnosis of subacromial bursitis or rotator cuff pathosis. Eighty-five consecutive patients undergoing shoulder arthroscopy by a single surgeon were documented prospectively for the positive and negative clinical and arthroscopic pathologic findings. The Neer sign was found to have a sensitivity of 75% for the appearance suggestive of subacromial bursitis; this compared with 92% for the Hawkins sign. For rotator cuff tearing, the sensitivity of the Neer sign was 85% and the sensitivity of the Hawkins sign was 88%. Specificity and positive predictive values for the two tests were low, being not much higher than pretest probability. The two tests had a high negative predictive value (96% for bursitis, 90% for rotator cuff tearing) when they were combined. The results are compared with those reported in the literature. We conclude that the Neer and Hawkins signs are sensitive for appearances suggestive of subacromial bursitis and rotator cuff partial or complete tearing with a high negative predictive value. However, they lack specificity in comparison with arthroscopic findings.
11. [Functional results of type A botulinum toxin versus oral anti-inflammatory agents in the rehabilitation of painful shoulder syndrome caused by rotator cuff lesion].
Science.gov (United States)
Becerril, Bautista P; Negrete-Corona, J; Chávez-Hinojosa, E
2014-01-01
Rotator cuff conditions are characterized by unspecific signs, as well as anatomic alterations and symptoms. They have a multifactorial etiology and may include everything from tendinitis to massive, full thickness tears of the rotator cuff tendon that compromise the normal biomechanics of the involved shoulder. They usually occur in people over 40 years of age but lesions resulting from trauma may vary according to the mechanism of injury and are not directly related with the age at onset of symptoms. Vascular factors have been described as related with rotator cuff tendon damage in conditions affecting the microcirculation. However, recent studies have not proven that the tendon under direct observation shows hypovascularity. Type A botulinum toxin acts by blocking the release of acetylcholine in the neuromuscular plate; in the joints it releases capsular tension and reduces proinflammatory factors such as interleukin-1 (IL-1). There are only a few papers on its intraarticular benefit; in muscle and tendon groups it not only has a muscle relaxant effect, but several publications support its utility for pain management. It has been widely used in the rehabilitation of this group of patients at low doses. Material and methods: Prospective, investigational and longitudinal study involving the follow-up of 24 patients with a diagnosis of painful shoulder syndrome proven clinically and with imaging tests, and caused by rotator cuff lesions. The patients either did not meet the criteria for immediate surgical repair or had already undergone such a repair. Type A botulinum toxin was applied to 12 patients in the subacromial space around the rotator cuff conjoint tendon, as well as in the painful spots and in the muscle contracture in the shoulder. The total dose of Type A botulinum toxin was 200 IU. The control group, also composed of 12 patients, was given a COX-2 oral antiinflammatory agent for 6 weeks (Celecoxib, 100 mg BID). Both groups followed a pre
12. Methicillin-resistant Staphylococcus aureus infection of the subacromial bursa: an unusual complication following subacromial corticosteroid injection (a report of two cases).
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Teoh, Kar H; Jones, Sian A; Gurunaidu, Subramaniam; Pritchard, Mark G
2015-07-01
Subacromial corticosteroid injections are frequently used for both diagnostic and therapeutic purposes in shoulder pain. Subacromial septic bursitis is a recognized but rare complication. There have been no reports of methicillin-resistant Staphylococcus aureus infections of the subacromial bursa after subacromial injections in the literature. We describe case reports of two patients who presented with subacromial methicillin-resistant Staphylococcus aureus septic bursitis following subacromial corticosteroid injections in the community and highlight the diagnostic and management challenges of this condition.
13. Methicillin-resistant Staphylococcus aureus infection of the subacromial bursa: an unusual complication following subacromial corticosteroid injection (a report of two cases)
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Teoh, Kar. H.; Jones, Sian A; Gurunaidu, Subramaniam; Pritchard, Mark G.
2014-01-01
Subacromial corticosteroid injections are frequently used for both diagnostic and therapeutic purposes in shoulder pain. Subacromial septic bursitis is a recognized but rare complication. There have been no reports of methicillin-resistant Staphylococcus aureus infections of the subacromial bursa after subacromial injections in the literature. We describe case reports of two patients who presented with subacromial methicillin-resistant Staphylococcus aureus septic bursitis following subacromi...
14. A manual physical therapy approach versus subacromial corticosteroid injection for treatment of shoulder impingement syndrome: a protocol for a randomised clinical trial
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Boyles, Robert E; Cleland, Joshua A; Brown, David L
2011-01-01
Introduction Corticosteroid injections (CSI) are a recommended and often-used first-line intervention for shoulder impingement syndrome (SIS) in primary care and orthopaedic settings. Manual physical therapy (MPT) offers a non-invasive approach with negligible risk for managing SIS. There is limited evidence to suggest significant long-term improvements in pain, strength and disability with the use of MPT, and there are conflicting reports from systematic reviews that question the long-term efficacy of CSI. Specifically, the primary objective is to compare the effect of CSI and MPT on pain and disability in subjects with SIS at 12 months. Design This pragmatic randomised clinical trial will be a mixed-model 2×5 factorial design. The independent variables are treatment (MPT and CSI) and time with five levels from baseline to 1 year. The primary dependent variable is the Shoulder Pain and Disability Index, and the secondary outcome measures are the Global Rating of Change and the Numeric Pain Rating Scale. For each ANOVA, the hypothesis of interest will be the two-way group-by-time interaction. Methods and analysis The authors plan to recruit 104 participants meeting established impingement criteria. Following examination and enrolment, eligible participants will be randomly allocated to receive a pragmatic approach of either CSI or MPT. The MPT intervention will consist of six sessions, and the CSI intervention will consist of one to three sessions. All subjects will continue to receive usual care. Subjects will be followed for 12 months. Dissemination and ethics The protocol was approved by the Madigan Army Medical Center Institutional Review Board. The results may have an impact on clinical practice guidelines. This study was funded in part by the Orthopaedic Physical Therapy Products Grant through the American Academy of Orthopaedic Manual Physical Therapists. Trial Registration http://clinicaltrials.gov/ NCT01190891. PMID:22021870
15. Physical therapist management following rotator cuff repair for a patient with postpolio syndrome.
Science.gov (United States)
2007-02-01
Postpoliomyelitis sequelae, such as gait instability and progressive weakness, predispose people with postpolio syndrome to secondary disabilities. With aging, people who depend on their upper extremities to accommodate lower-extremity deficits may anticipate overuse injuries. The purpose of this case report is to describe the use of mobilization and exercise in postoperative rehabilitation of rotator cuff surgery on a patient with postpolio syndrome. A 48-year-old woman with postpolio syndrome had rotator cuff surgical repair followed by physical therapy intervention. Maitland mobilization and mild functional exercises were chosen to avoid triggering fatigue. Measurements taken preoperatively, before and after physical therapy intervention, and 2 years after intervention showed return to independent status with excellent retention. No fatigue or overuse weakness was encountered. This is the first case report to document physical therapy following rotator cuff repair in a patient with postpolio syndrome.
16. Subacromial impingement in patients with whiplash injury to the cervical spine
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Giddins Grey E
2008-06-01
Full Text Available Abstract Background Impingement syndrome and shoulder pain have been reported to occur in a proportion of patients following whiplash injuries to the neck. In this study we aim to examine these findings to establish the association between subacromial impingement and whiplash injuries to the cervical spine. Methods and results We examined 220 patients who had presented to the senior author for a medico-legal report following a whiplash injury to the neck. All patients were assessed for clinical evidence of subacromial impingement. 56/220 patients (26% had developed shoulder pain following the injury; of these, 11/220 (5% had clinical evidence of impingement syndrome. Only 3/11 patients (27% had the diagnosis made prior to evaluation for their medico-legal report. In the majority, other clinicians had overlooked the diagnosis. The seatbelt shoulder was involved in 83% of cases (p Conclusion After a neck injury a significant proportion of patients present with shoulder pain, some of whom have treatable shoulder pathology such as impingement syndrome. The diagnosis is, however, frequently overlooked and shoulder pain is attributed to pain radiating from the neck resulting in long delays before treatment. It is important that this is appreciated and patients are specifically examined for signs of subacromial impingement after whiplash injuries to the neck. Direct seatbelt trauma to the shoulder is one possible explanation for its aetiology.
17. Accuracy of diagnostic ultrasound in patients with suspected subacromial disorders: a systematic review and meta-analysis.
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Ottenheijm, Ramon P; Jansen, Mariëtte J; Staal, J Bart; van den Bruel, Ann; Weijers, René E; de Bie, Rob A; Dinant, Geert-Jan
2010-10-01
To determine the diagnostic accuracy of ultrasound for detecting subacromial disorders in patients presenting in primary and secondary care settings. Medline and Embase were searched on June 9, 2010. In addition, the reference list of 1 systematic review and all included articles were searched to identify relevant studies. Two reviewers independently selected the articles evaluating the accuracy of ultrasound for detecting subacromial disorders from the title and abstracts retrieved by the literature search. Selection criteria were ultrasound frequency greater than or equal to 7.5MHz as index test, surgery, magnetic resonance imaging and/or radiography as reference standards, and subacromial disorders as target conditions. Two reviewers independently extracted the data on study characteristics and results to construct 2 by 2 tables and performed a methodologic quality assessment. Twenty-three studies were included: 22 reported on full-thickness rotator cuff tears, 15 on partial-thickness tears, 3 on subacromial bursitis, 2 on tendinopathy, and 2 on calcifying tendonitis, respectively. For full-thickness tears, pooled sensitivity of ultrasound was .95 (95% confidence interval, .90-.97), and specificity .96 (.93-.98). For partial-thickness tears, pooled sensitivity was .72 (.58-.83), and specificity .93 (.89-.96). Statistical pooling was not possible for the other disorders. For subacromial bursitis, sensitivity ranged from .79 to .81, and specificity from .94 to .98. For tendinopathy, sensitivity ranged from .67 to .93, specificity from .88 to 1.00. Sensitivity for calcifying tendonitis was 1.00 in both studies, with specificity ranging from .85 to .98. We strongly recommend ultrasound in patients for whom conservative treatment fails, to rule in or out full-thickness tears, to rule in partial-thickness tears, and to a lesser extent to diagnose tendinopathy, subacromial bursitis, and calcifying tendonitis. These results can help physicians tailor treatment
18. Physiotherapy intervention in subacromial impingement syndrome
OpenAIRE
Cardoso, Ricardo Manuel Tavares; Leite, Marcelo Soares Oliveira
2013-01-01
INTRODUÇÃO: Os problemas do ombro são responsáveis por cerca de 10% de todos os encaminhamentos para os fisioterapeutas, sendo a síndrome de colisão do ombro o diagnóstico mais comum entre as patologias do ombro, representando 44 a 65%. Contudo, a efectividade da fisioterapia nesta patologia continua a ser um tema em discussão. OBJECTIVO: Determinar a efectividade da fisioterapia no tratamento de pacientes com síndrome de colisão do ombro. METODOLOGIA: Pesquisa computadorizada nas bases de da...
19. Subacute effects of cervicothoracic spinal thrust/non-thrust in addition to shoulder manual therapy plus exercise intervention in individuals with subacromial impingement syndrome: a prospective, randomized controlled clinical trial pilot study.
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Wright, Alexis A; Donaldson, Megan; Wassinger, Craig A; Emerson-Kavchak, Alicia J
2017-09-01
To determine the subacute effects of cervicothoracic spinal thrust/non-thrust in addition to shoulder non-thrust plus exercise in patients with subacromial pathology. This was a randomized, single blinded controlled trial pilot study. This trial was registered at ClinicalTrials.gov (NCT01753271) and reported according to Consolidated Standards of Reporting Trials requirements. Patients were randomly assigned to either shoulder treatment plus cervicothoracic spinal thrust/non-thrust or shoulder treatment-only group. Primary outcomes were average pain intensity (Numeric Pain Rating Scale) and physical function (Shoulder Pain and Disability Index) at 2 weeks, 4 weeks, and patient discharge. 18 patients, mean age 43.1(15.8) years satisfied the eligibility criteria and were analyzed for follow-up data. Both groups showed statistically significant improvements in both pain and function at 2 weeks, 4 weeks, and discharge. The between-group differences for changes in pain or physical function were not significant at any time point. The addition of cervicothoracic spinal thrust/non-thrust to the shoulder treatment-only group did not significantly alter improvement in pain or function in patients with subacromial pathology. Both approaches appeared to provide an equally notable benefit. Both groups improved on all outcomes and met the criteria for clinical relevance for both pain and function. 2b.
20. Rotations
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John R. Jones; Wayne D. Shepperd
1985-01-01
The rotation, in forestry, is the planned number of years between formation of a crop or stand and its final harvest at a specified stage of maturity (Ford-Robertson 1971). The rotation used for many species is the age of culmination of mean usable volume growth [net mean annual increment (MAI)]. At that age, usable volume divided by age reaches its highest level. That...
1. In vivo temperature measurement in the subacromial bursa during arthroscopic subacromial decompression.
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Barker, Scott L; Johnstone, Alan J; Kumar, Kapil
2012-06-01
The purpose of the study was to evaluate whether use of a bi-polar radiofrequency (RF) ablation wand would cause excess heating, which may lead to collateral damage to the surrounding tissues during arthroscopic subacromial decompression. Cadaveric studies have shown that high temperatures can potentially be reached when using RF ablation wands in arthroscopic shoulder surgery. Only 1 other published study assesses these temperature rises in the clinical setting. Fifteen patients were recruited to participate in the study. A standard arthroscopic subacromial decompression was performed using continuous flow irrigation, with intermittent use of the RF ablation wand for soft tissue debridement. The temperature of the irrigation fluid within the subacromial bursa and the outflow fluid from the suction port of the wand were measured during the procedure using fiber-optic thermometers. The mean peak temperature recorded in the subacromial bursa was 32.0°C (29.3-43.1°C), with a mean rise from baseline of 9.8°C. The mean peak temperature recorded from the outflow fluid from the wand was 71.6°C (65.6-77.6°C), with a mean rise from baseline of 49.4°C. High temperatures were noted in the outflow fluid from the wand; however, this was not evident in the subacromial bursa itself. Use of room temperature inflow fluid, maintenance of flow through the bursa, and avoidance of prolonged uninterrupted use of the wand all appear to ensure that safe temperatures are maintained in the subacromial bursa not only in the laboratory but also in a clinical setting. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.
2. Subacromial Bursa Injection of Hyaluronate with Steroid in Patients with Peri-articular Shoulder Disorders
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Byun, Seung Deuk; Choi, Won Duck; Lee, Zee Ihn
2011-01-01
Objective To investigate the additive effect of sono-guided subacromial bursa injection of hyaluronate with steroid in patients with peri-articular shoulder disorders. Method This prospective randomized controlled trial involved 26 patients who had shoulder pain. Group A, consisting of 13 patients, was treated with a sono-guided subacromial bursa injection containing a mixture of 0.5% lidocaine (5 ml) and triamcinolone 40 mg (1 ml), followed by injection with sodium hyaluronate (2 ml) once a week for 3 weeks. The other 13 patients (Group B) were treated with a sono-guided subacromial bursa injection containing a mixture of 0.5% lidocaine (5 ml) and triamcinolone 40 mg (1 ml) once a week for 3 weeks. The effects were assessed using a visual analogue scale (VAS) of shoulder pain, active range of motion (AROM), shoulder function assessment scale (SFA), shoulder disability questionnaire (SDQ) at study entry and every week from first injection until 4 weeks after the 1st injection (= 2 weeks after 3rd injection). Results (1) Demographic features and all parameters measured before injection did not show a significant difference between the 2 groups. (2) Statistically significant improvements were shown in VAS, SFA, SDQ during the 1st, 2nd, and 4th week after the first injection in both groups (pbursa injection of hyaluronate with steroid in patients with peri-articular shoulder disorders has additive effects on functional improvement of the affected shoulder, including the AROM of internal rotation. PMID:22506189
3. Ultrasonography of the Rotator Cuff
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Yoon, Yong Cheol [Samsung Medica Center, Sungkyunkwan University College of Medicine, Seoul (Korea, Republic of)
2006-09-15
The ultrasonography (US) is an important modality in evaluating shoulder disease. It is accurate in diagnosing the various shoulder diseases including tendinosis, calcific tendinitis, and subacromial bursitis as well as rotator cuff tears. This article presents a pictorial review of US anatomy of the shoulder, the technical aspects of shoulder US, major types of shoulder pathology, and interventional procedure under US guidance
4. Involvement of the anterior portion of the subacromial-subdeltoid bursa in the painful shoulder.
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Stallenberg, Bernard; Destate, Nathalie; Feipel, Véronique; Gevenois, Pierre Alain
2006-10-01
The purpose of our study was to verify that increased widening of the anterior portion of the subacromial-subdeltoid bursa is associated with anteromedial shoulder pain. Bursography, sonography, and CT were performed in six cadaver shoulders and compared with anatomic sections in neutral position and while the humerus was extended and internally rotated. For the clinical study, the width of the anterior portion of the bursa was measured in both positions in both shoulders of 27 patients referred because of shoulder pain and in eight asymptomatic volunteers. Pain was coded as absent, experienced in the anteromedial portion of the shoulder, or experienced elsewhere but not anteromedially, and we compared the pain scores between shoulder positions. In all cadaver shoulders, when compared with CT scans and anatomic sections, sonography showed the morphology of the bursa, its relationships with surrounding structures, and morphologic changes associated with position. In volunteers, the mean width of the bursa was 0.74 +/- 0.05 and 0.93 +/- 0.09 mm (p = 0.013), respectively, in neutral and stress position. In patients, the same values were 0.70 +/- 0.07 and 0.81 +/- 0.14 mm (p = 0.286) in the asymptomatic side and 1.20 +/- 0.11 and 1.75 +/- 0.23 mm (p bursa was wider in patients experiencing pain anteromedially than in those who experienced pain elsewhere and volunteers (p = 0.002 and bursa was wider in symptomatic shoulders than in asymptomatic shoulders (p bursa is associated with anteromedial shoulder pain and the clinical syndrome of coracoid impingement.
5. Do subacromial ultrasonography findings predict efficacy of intra-bursal injection? Prospective study in 39 patients.
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Bouju, Y; Bouilleau, L; Dubois de Montmarin, G; Bacle, G; Favard, L
2014-12-01
Ultrasonography has become an investigation of choice in the management of shoulder pain. The objective of this study was to determine whether the efficacy of subacromial-subdeltoid bursa injection correlated with the ultrasound findings. We prospectively recruited patients who were seen between November 2012 and November 2013 for subacromial pain and whose rotator cuff was either intact or showed a full-thickness tear less than 1cm in length. A standardised physical examination of the shoulder was followed immediately by static and dynamic ultrasonography, intra-bursal injection of lidocaine, and a repetition of the same physical examination. Recorded ultrasonography features were the appearance of the bursa, shape of the coraco-acromial ligament, and bursal deformation induced by passage under the coraco-acromial ligament during dynamic imaging. A response to the injection was defined as greater than 75% improvements in at least three of the physical examination parameters. We included 39 patients with a mean age of 56.7 years. Ultrasonography showed abnormalities of the bursa in 30 patients, including 1 with an intra-bursal effusion, 10 with thickening, and 19 with both. Deformation of the bursa under the coraco-acromial ligament was noted in 26 patients. The proportions of patients with bursal effusion and with bursal thickening were similar in the 20 responders and 19 non-responders. Neither were any significant differences found for coraco-acromial ligament shape or bursal deformation under the ligament. No correlation was found between ultrasonography findings and the efficacy of a local anaesthetic injection into the subacromial bursa. These findings suggest that ultrasound abnormalities may constitute mere physiological changes, in keeping with earlier studies in asymptomatic individuals. Thus, subacromial impingement may be currently overdiagnosed. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
6. Prevalence of Propionibacterium acnes in the glenohumeral compared with the subacromial space in primary shoulder arthroscopies.
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Patzer, Thilo; Petersdorf, Sabine; Krauspe, Ruediger; Verde, Pablo Emilio; Henrich, Birgit; Hufeland, Martin
2018-01-18
We hypothesized that the prevalence of Propionibacterium acnes in patients undergoing primary shoulder arthroscopy is equal in the glenohumeral space compared with the subacromial space. Patients aged 18 years or older with shoulder arthroscopies were included. The exclusion criteria were prior shoulder operations, complete rotator cuff tears, systemic inflammatory diseases, tumors, shoulder injections within 6 months of surgery, and antibiotic therapy within 14 days preoperatively. After standardized skin disinfection with Kodan Tinktur Forte Gefärbt, a skin swab was taken at the posterior portal. Arthroscopy was performed without cannulas, prospectively randomized to start either in the glenohumeral space or in the subacromial space, with direct harvesting of a soft-tissue biopsy specimen. Sample cultivation was conducted according to standardized criteria for bone and joint aspirate samples and incubated for 14 days. Matrix-assisted laser desorption-ionization time-of-flight spectrometry was used for specimen identification in positive culture results. The study prospectively included 115 consecutive patients with normal C-reactive protein levels prior to surgery (54.8% men; mean age, 47.2 ± 14.6 years). P acnes was detected on the skin after disinfection in 36.5% of patients, in the glenohumeral space in 18.9%, and in the subacromial space in 3.5% (P = .016). The prevalence of P acnes is significantly higher in the glenohumeral space compared with the subacromial space in primary shoulder arthroscopies. The results do not confirm the contamination theory but also cannot clarify whether P acnes is a commensal or enters the joint hematologically or even lymphatically or via an unknown pathway. Despite standardized surgical skin disinfection, P acnes can be detected in skin swab samples in more than one-third of patients. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
7. Unusual lesions mimicking impingement syndrome in the shoulder joint - Think medially.
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Singh, Rohit; Malhotra, Akshay; Cribb, Gillian; Cool, Paul; Hay, Stuart
2016-09-01
Impingement syndrome is usually caused by irritation of the rotator cuff within the sub acromial space and this includes the coraco-acromial arch (Acromion and Coraco-acromial ligament), the acromio-clavicular joint and occasionally the coracoid. Iatrogenic causes such as sutures, pins, plates or wires left from previous surgery can cause similar symptoms. We present a series of four cases mimicking "classical" impingement symptoms/signs in which the causal pathology was identified outside the sub-acromial space. Magnetic Resonance Imaging (MRI) showed lesions that were present in the supra-spinatus fossa but were causing pressure effects on the sub-acromial space, namely - a ganglion cyst in one case, lipomata in two other cases, and a glomus tumour. A ganglion cyst and glomus tumour mimicking impingement syndrome is a rare reported case to our knowledge. These are unusual causes that should be considered when investigating classical impingement syndrome and particularly those who may have failed to respond to decompression surgery. They highlight the potential value of looking beyond the sub-acromial space for causal lesions and in these cases, at a time when limited ultrasound investigation has become increasingly popular; MRI has clearly played an important and was essential in planning surgery as these lesions would not have been identified on USS. Even though the symptoms were classical.
8. Impingement syndrome of the shoulder following double row suture anchor technique for arthroscopic rotator cuff repair: a case report
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Rambani Rohit
2009-06-01
Full Text Available Abstract Introduction Arthroscopic repair of the rotator cuff is a demanding surgery. Accurate placement of anchors is key to success. Case presentation A 38-year-old woman received arthroscopic repair of her rotator cuff using a double row suture anchor technique. Postoperatively, she developed impingement syndrome which resulted from vertical displacement of a suture anchor once the shoulder was mobilised. The anchor was removed eight weeks following initial surgery and the patient had an uneventful recovery. Conclusion Impingement syndrome following arthroscopic repair of the rotator cuffs using double row suture anchor has not been widely reported. This is the first such case where anchoring has resulted in impingement syndrome.
9. Typical and atypical shoulder impingement syndrome: diagnosis, treatment, and pitfalls.
Science.gov (United States)
Buss, Daniel D; Freehill, Michael Q; Marra, Guido
2009-01-01
The cause of shoulder impingement syndrome usually is considered to be compression of the rotator cuff and subacromial bursa against the anterolateral aspect of the acromion. The typical symptom is anterolateral shoulder pain that worsens at night and with overhead activity. However, the pain may be caused by factors other than a hooked acromion. Atypical impingement syndrome most commonly results from an os acromiale, a subcoracoid disorder, acromioclavicular joint undersurface hypertrophy, a deconditioned rotator cuff, or scapular dyskinesis. The correct diagnosis is made through the patient history and physical examination, with appropriate diagnostic imaging. Nonsurgical treatment is successful for most types of impingement syndrome; if it is not successful, all structural causes of mechanical impingement must be corrected.
10. The role of experimentally-induced subacromial pain on shoulder strength and throwing accuracy.
Science.gov (United States)
Wassinger, Craig A; Sole, Gisela; Osborne, Hamish
2012-10-01
Shoulder injuries often comprise two separate yet related components, structural tissue damage and pain. The role of each of these components on shoulder function is difficult to ascertain. Experimental pain models allow the assessment of consequences of localized pain when applied to healthy individuals. By understanding the role of pain on shoulder function, clinicians will be able to more efficiently assess and treat shoulder injuries. The objective of the study was to evaluate the role of experimentally-induced sub-acromial pain on shoulder isokinetic rotational strength and throwing accuracy. This was a block counterbalanced, crossover, repeated measures study design utilizing 20 individuals without self-reported shoulder or cervical pathology. Shoulder function was measured with and without experimental pain injection (2 mL of 5% hypertonic saline) in the sub-acromial space. Functional tasks consisted of shoulder rotational strength utilizing isokinetic testing and throwing accuracy via the functional throwing performance index. The hypertonic saline induced moderate pain levels in all participants (4.3-5.1/10). Normalized shoulder internal (t = 3.76, p = 0.001) and external (t = 3.12, p = 0.006) rotation strength were both diminished in the painful condition compared to the pain free condition. Throwing accuracy was also reduced while the participants experienced pain (t = 3.99, p = 0.001). Moderate levels of experimental shoulder pain were sufficient to negatively influence shoulder strength and throwing accuracy in participants without shoulder pathology. Copyright © 2012 Elsevier Ltd. All rights reserved.
11. Analgesia para a sutura artroscópica do manguito rotador: estudo comparativo entre o bloqueio interescalênico do plexo braquial e o bloqueio da bursa subacromial contínuo Management of pain after the rotator cuff arthroscopic suture: comparative study among the interescalenic blockade and the continuous intrabursal infusion
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Alexandre Almeida
2007-10-01
12. Diagnostic Accuracy of Clinical Examination and Imaging Findings for Identifying Subacromial Pain.
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Full Text Available The diagnosis of subacromial pathology is limited by the poor accuracy of clinical tests for specific pathologies. The aim of this study was to estimate the diagnostic accuracy of clinical examination and imaging features for identifying subacromial pain (SAP defined by a positive response to diagnostic injection, and to evaluate the influence of imaging findings on the clinical diagnosis of SAP.In a prospective, diagnostic accuracy design, 208 consecutive patients presenting to their primary healthcare practitioner for the first time with a new episode of shoulder pain were recruited. All participants underwent a standardized clinical examination, shoulder x-ray series and diagnostic ultrasound scan. Results were compared with the response to a diagnostic block of xylocaineTM injected into the SAB under ultrasound guidance using ≥80% post-injection reduction in pain intensity as the positive anaesthetic response (PAR criterion. Diagnostic accuracy statistics were calculated for combinations of clinical and imaging variables demonstrating the highest likelihood of a PAR. A PAR was reported by 34% of participants. In participants with no loss of passive external rotation, combinations of three clinical variables (anterior shoulder pain, strain injury, absence of symptoms at end-range external rotation (in abduction demonstrated 100% specificity for a PAR when all three were positive (LR+ infinity; 95%CI 2.9, infinity. A full-thickness supraspinatus tear on ultrasound increased the likelihood of a PAR irrespective of age (specificity 98% (95%CI 94, 100; LR+ 6.2; 95% CI 1.5, 25.7. Imaging did not improve the ability to rule-out a PAR.Combinations of clinical examination findings and a full-thickness supraspinatus tear on ultrasound scan can help confirm, but not exclude, the presence of subacromial pain. Other imaging findings were of limited value for diagnosing SAP.
13. Suture slippage in knotless suture anchors resulting in subacromial-subdeltoid bursitis.
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Hayeri, Mohammad Reza; Keefe, Daniel T; Chang, Eric Y
2016-05-01
Rotator cuff repair using a suture bridge and knotless suture anchors is a relatively new, but increasingly used technique. The suture bridge technique creates an anatomically similar and more secure rotator cuff repair compared with conventional arthroscopic techniques and the use of knotless anchors eliminates the challenges associated with knot tying during arthroscopic surgery. However, previous in vitro biomechanical tests have shown that the hold of the suture in a knotless suture anchor is far lower than the pullout strength of the anchor from bone. Up until now slippage has been a theoretical concern. We present a prospectively diagnosed case of in vivo suture loosening after rotator cuff repair using a knotless bridge technique resulting in subacromial-subdeltoid bursitis.
14. Rehabilitation for Subacromial Impingement Starts at the Scapula
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Peggy A. Houglum
2013-12-01
Full Text Available Subacromial impingement, especially secondary subacromial impingement, is a common malady of athletes and non-athletes alike. Although several pathologies may lead to impingement, they all relate back to poor posture. Over time, postural changes increase stress to soft tissue structures to change both alignment and performance. Injury results as low-level stresses impact weakening tissues to the point of overload. Crucial to effective treatment of secondary subacromial impingement is the identification and correction of all causes. Basic to successful treatment is correction of posture, including scapular posture and muscles which control, stabilize, and move the scapula. An evidence-based approach to not only identifying the causes but also creating a treatment regimen to effectively resolve secondary subacromial impingement is presented.
15. The accurate assessment and physiotherapeutic treatment of rotator cuff myofascial Pain Syndrome: A case report
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B. B. Barker
2011-02-01
Full Text Available Management of patients with rotator cuff myofascial pain syndrome varies and successful intervention is dependent on accurate assessment. The aim of this case report is to show the importance of accurate assessment and clinical reasoning in the physiotherapeutic management of a patient suffering from ante-cubital and anterior shoulder pain. The patient was referred for physiotherapy after proving refractory to treatment with non-steroidal anti-inflammatory medication. The physiotherapist diagnosed a rotator cuff myofascial pain syndrome and treatment proceeded on that basis. Treatment consisted of twitch-obtaining dry needling, myofascial release and exercise therapy. The result was a change in the harryman rotator cuff functional Assessment Scale score from 22/52 to 43/52 over eight treatments. Strength was regained and subjective pain report on the visual rating scale was improved to 1/10. The case study highlights the importance of accurate assessment and consideration of alternative myofascial sources for pain even in circumstances which initially seem trauma related. Precise diagnosis of the cause - in this case rotator cuff myofascial pain syndrome – will result in effective treatment being administered.
16. Mycobacterium avium-intracellulare: a rare cause of subacromial bursitis.
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Sinha, Raj; Tuckett, John; Hide, Geoff; Dildey, Petra; Karsandas, Alvin
2015-01-01
Septic subacromial bursitis is an uncommon disorder with only a few reported cases in the literature. The most common causative organism is Staphylococcus aureus. We report the case of a 61-year-old female with a septic subacromial bursitis where the causative organism was found to be Mycobacterium avium-intracellulare (MAI). The diagnosis was only made following a biopsy, and we use this case to highlight the importance of recognising the need to consider a biopsy and aspiration in atypical situations.
17. Current UK practices in the management of subacromial impingement
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Drury, Colin; Tait, Gavin R
2015-01-01
Background Controversy presently exists surrounding the management of patients with subacromial impingement. This study aims to highlight current UK practices in the management of these patients. Methods BESS members were invited to complete a questionnaire and responses were received from 157 consultant shoulder surgeons. Results Physiotherapy is an integral part of management for 93% of surgeons with a minimum period of 12 weeks being most popular prior to consideration of arthroscopic subacromial decompression. Subacromial steroid injection is used by 95% and 86% repeat this if the patient has failed to respond to a previous injection by the general practioner. From initial presentation, 77% felt there should be at least 3 months of conservative management before proceeding to surgery. Good but transient response to subacromial injection was considered the best predictor of good surgical outcome by 77%. The coracoacromial ligament is fully released by 78%, although there was greater variation in how aggressive surgeons were with acromioplasty. Most (59%) do not include the nontender acromioclavicular joint to any extent in routine acromioplasty. Hospital physiotherapy protocols are used by 63% for postoperative rehabilitation. Conclusions Variation exists in the management regimes offered to patients with subacromial impingement, but most employ a minimum period of 12 weeks of conservative management incorporating physiotherapy and at least 2 subacromial steriod injections. PMID:27582972
18. Comparison of surgical outcome in impingement syndrome with and without stiff shoulder.
Science.gov (United States)
Park, Jin-Young; Pandher, Dilbans Singh; Moon, Gi-Hyuk; Yoo, Moon-Jib; Lee, Sung Tae
2008-04-01
In impingment syndrome with associated stiff shoulder the general protocol of management is to conservatively treat the stiff shoulder followed by operative treatment of the impingement syndrome. This consecutive prospective study was carried out to evaluate the functional outcome of surgical management for impingement syndrome associated with stiff shoulder and to compare the results with surgical management of impingement syndrome alone. We evaluated a total of 100 patients with impingement syndrome, consisting of 76 patients with impingement syndrome alone (Group A) and 24 patients of stiff shoulder associated with impingement syndrome (Group B). Group A patients were treated by subacromial decompression alone and Group B patients were treated by closed manipulation under anesthesia followed by subacromial decompression. According to the American Shoulder and Elbow Surgeons (ASES) evaluation score satisfactory results were obtained in 80% patients of Group A and 67% patients of Group B, while for patients with diabetes [(n = 18), Group A (n = 11), Group B (n = 7)] satisfactory results were achieved in 82% of patients of Group A(9/11) and 43% of Group B(3/7). Overall, Group B patients had a lower range of motion for external rotation postoperatively, thus indicating that procedures to improve the external rotation, such as a release of the rotator interval or anterior capsule, might be considered in conjunction with other surgical procedures in patients with impingement syndrome with associated stiffness to further improve functional outcome. Acromioplasty can be performed in stiff shoulder associated with impingement syndrome without fears of further worsening of stiffness from adhesions with the exposed raw undersurface of acromian. Patients with diabetes mellitus and shoulder stiffness tend to have poor clinical outcomes and must receive appropriate counseling preoperatively.
19. Comparison of surgical outcome in impingement syndrome with and without stiff shoulder
Directory of Open Access Journals (Sweden)
Park Jin-Young
2008-01-01
Full Text Available Background: In impingment syndrome with associated stiff shoulder the general protocol of management is to conservatively treat the stiff shoulder followed by operative treatment of the impingement syndrome. This consecutive prospective study was carried out to evaluate the functional outcome of surgical management for impingement syndrome associated with stiff shoulder and to compare the results with surgical management of impingement syndrome alone. Materials and Methods: We evaluated a total of 100 patients with impingement syndrome, consisting of 76 patients with impingement syndrome alone (Group A and 24 patients of stiff shoulder associated with impingement syndrome (Group B. Group A patients were treated by subacromial decompression alone and Group B patients were treated by closed manipulation under anesthesia followed by subacromial decompression. Results: According to the American Shoulder and Elbow Surgeons (ASES evaluation score satisfactory results were obtained in 80% patients of Group A and 67% patients of Group B, while for patients with diabetes [( n = 18, Group A (n = 11, Group B (n = 7] satisfactory results were achieved in 82% of patients of Group A(9/11 and 43% of Group B(3/7. Overall, Group B patients had a lower range of motion for external rotation postoperatively, thus indicating that procedures to improve the external rotation, such as a release of the rotator interval or anterior capsule, might be considered in conjunction with other surgical procedures in patients with impingement syndrome with associated stiffness to further improve functional outcome. Conclusion: Acromioplasty can be performed in stiff shoulder associated with impingement syndrome without fears of further worsening of stiffness from adhesions with the exposed raw undersurface of acromian. Patients with diabetes mellitus and shoulder stiffness tend to have poor clinical outcomes and must receive appropriate counseling preoperatively.
20. The effects of low arched feet on foot rotation during gait in children with Down syndrome.
Science.gov (United States)
Galli, M; Cimolin, V; Rigoldi, C; Pau, M; Costici, P; Albertini, G
2014-08-01
In children with Down syndrome (DS) hypotonia and ligament laxity are characteristic features which cause a number of orthopaedic issues, such as flat foot. The aim of this study was to determine if children with flat foot are characterised by an accentuated external foot rotation during walking. Fifty-five children with DS and 15 typically developing children recruited as control group were assessed using three-dimensional gait analysis, using an optoelectronic system, force platforms and video recording. Parameters related to foot rotation were identified and calculated and the participants' foot morphology was assessed using the arch index. Data obtained in this study showed that while DS children without flat foot displayed the foot position on the transverse plane globally close to controls during the whole gait cycle, the DS children with flat foot were characterised by higher extra-rotation of the foot in comparison with those without flat foot and controls. Our results suggest that the presence of flatfoot lead the children with DS to extra-rotate their feet more than the children without flat foot. From a clinical point of view, these results could enhance the rehabilitative programmes in DS. © 2013 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.
1. Isolated subacromial bursal fluid on MRI of the shoulder in symptomatic patients: correlation with arthroscopic findings
Energy Technology Data Exchange (ETDEWEB)
Monu, J.U.V. [Dept. of Radiology, Bowman Gray School of Medicine, Wake Forest Univ., Winston-Salem, NC (United States); Pruett, S. [Bowman Gray School of Medicine, Wake Forest Univ., Winston-Salem, NC (United States); Vanarthos, W.J. [Dept. of Radiology, Bowman Gray School of Medicine, Wake Forest Univ., Winston-Salem, NC (United States); Pope, T.L. Jr. [Dept. of Radiology, Bowman Gray School of Medicine, Wake Forest Univ., Winston-Salem, NC (United States)
1994-10-01
Fluid in the subacromial bursa (SAB) is a common finding on magnetic resonance (MR) images of the shoulder, and the implications of this finding have not been clarified. We retrospectively reviewed and correlated the MR features with arthroscopic findings in 21 symptomatic patients who had fluid in the SAB on MR imaging without demonstrable rotator cuff tear. Rotator cuff impingement was the most frequent surgical finding (42.9%). Other frequent surgical observations were glenbid labrum abnormality (28.6%), bursitis (19%), and supraspinatus tendinitis (14.3%). Distribution of acromial types was similar to that reported by Bigliani et al., and impingement was evenly distributed among acromial types in our study population. We conclude that in our patient population group the MR finding of isolated SAB fluid in symptomatic patients is highly likely to be associated with the finding of other abnormalities in the shoulder joint at surgery. (orig.)
2. Acromion Types and Role of Corticosteroid with Shoulder Impingement Syndrome.
Science.gov (United States)
Akram, Muhammad; Shah Gillani, Syed Faraz Ul Hassan; Farooqi, Faheem Mubashir; Awais, Syed Muhammad
2016-12-01
To determine the association between shoulder impingement and morphological characteristics of acromion and the role of sub-acromial injection of methylprednisolone in the short-term treatment for relieving pain and improve functional disability of these patients. A descriptive study. Department of Orthopedic Surgery and Traumatology Unit-I (DOST-I), Mayo Hospital, Lahore, between November 2013 to June 2014. All patients presented in OPD with shoulder pain were included as subjects and evaluated by clinical test and categorised using X-ray scapula Y-view. Patients with impingement syndrome were correlated with Bigliani types and offered intra-lesional injection into sub-acromial space with 2ml of xylocaine 2% and 40 mg of methylprednisolone using 22 gauge needle. The effectiveness was assessed in terms of relieving pain and good functional outcomes; and rotator cuff tear was clinically assessed among impingement positive patient. The pain was assessed using visual analogue score before and after the administration of the injection. Demographic variables for frequencies and their associations were analysed using SPSS version 20.0. Significance level was p shoulder impingement. Most had moderate pain. Thirty-four patients required intralesional steroid, which relieved the pain in 31 of them. Shoulder impingement syndrome without tear of rotator cuff tendon was found in younger age group between 40 to 45 years, which was relieved by intralesional corticosteroid administration. These patients had type II (curved) acromion, according to Bigliani classification.
3. Efficacy of Kinesiology Taping as an Adjunct Treatment of Shoulder Impingement Syndrome: A Systematic Review
National Research Council Canada - National Science Library
C A Fitch; T R Frendt; C L Lipinski; C D Moore; L Donovan
2017-01-01
... with shoulder impingement syndrome is presented. Kinesiology tape may be effective in reducing impairments, such as altered range of motion and decreased subacromial space, commonly associated with shoulder impingement syndrome...
4. Effects of Repetitive Shoulder Activity on the Subacromial Space in Manual Wheelchair Users
Directory of Open Access Journals (Sweden)
Yen-Sheng Lin
2014-01-01
Full Text Available This study investigated (1 the effect of repetitive weight-relief raises (WR and shoulder external rotation (ER on the acromiohumeral distance (AHD among manual wheelchair users (MWUs and (2 the relationship between shoulder pain, subject characteristics, and AHD changes. Twenty-three MWUs underwent ultrasound imaging of the nondominant shoulder in an unloaded baseline position and while holding a WR position before and after the WR/ER tasks. Paired t-tests and Spearman correlational analysis were used to assess differences in the AHD before and after each task and the relationships between pain, subject characteristics, and the AHD measures. A significant reduction in the subacromial space (P<0.01 occurred when subjects performed a WR position compared to baseline. Individuals with increased years of disability had greater AHD percentage narrowing after WR (P=0.008. Increased shoulder pain was associated with AHD percentage narrowing after ER (P≤0.007. The results support clinical practice guidelines that recommend MWUs limit WR to preserve shoulder function. The isolated repetitive shoulder activity did not contribute to the changes of subacromial space in MWUs. The ultrasonographic measurement of the AHD may be a target for identifying future interventions that prevent pain.
5. Is radiofrequency treatment effective for shoulder impingement syndrome? A prospective randomized controlled study.
Science.gov (United States)
Lu, Yi; Zhang, Qiang; Zhu, Yiming; Jiang, Chunyan
2013-11-01
6. Impingement syndrome of the shoulder following double row suture anchor technique for arthroscopic rotator cuff repair: a case report
OpenAIRE
Rambani Rohit; Hackney Roger G
2009-01-01
Abstract Introduction Arthroscopic repair of the rotator cuff is a demanding surgery. Accurate placement of anchors is key to success. Case presentation A 38-year-old woman received arthroscopic repair of her rotator cuff using a double row suture anchor technique. Postoperatively, she developed impingement syndrome which resulted from vertical displacement of a suture anchor once the shoulder was mobilised. The anchor was removed eight weeks following initial surgery and the patient had an u...
7. Subacromial bursitis related to HIV infection: case report.
Science.gov (United States)
Ejnisman, Benno; Figueiredo, Eduardo Antônio de; Terra, Bernardo Barcellos; Lima, Ana Lucia L Munhoz; Uip, David E
2010-01-01
Describe a subacromial bursitis at the right shoulder of a 45-year-old male subject. The patient has been living with HIV/AIDS for 22 years. The ultrasonography and the MRI revealed the presence of a pronounced subacromial effusion, with an inflammatory reaction of adjacent tissues. The tumoration was handled firstly with a needle-puncture aspiration, with a thick liquid outflow, followed by an open drainage. Histopathological evaluation showed no evidence of any AIDS defining disease. There was complete remission of the infection after five months thereafter the symptoms had started. After reviewing the scarce literature in the area, no reports of subacromial bursitis in HIV/AIDS patients were found. The authors point out that, although rare, this disease should be considered as differential diagnosis of shoulder diseases in HIV-infected subjects.
8. Subacromial bursitis with rice bodies : a case report
Energy Technology Data Exchange (ETDEWEB)
Kim, Bong Soo; Joo, Kyung Bin; Park, Dong Woo; Lee, Hak Soo; Oh, Jae Cheon; Lee, Yong Joo; Lee, Won Mi [Hanyang Univ., Seoul (Korea, Republic of). Coll. of Medicine
1998-04-01
Multiple rice bodies in joints or bursae are rarely encountered in patients with rheumatoid arthritis. We report the radiologic findings of massive subacromial bursitis with innumerable rice bodies on the right shoulder of a 38-year-old man with rheumatoid arthritis. Subacromial bursography showed markedly distended bursa with multiple nodular filling defects. Precontrast CT scanning revealed well-demarcated hypodense lesion without calcification in subacromio-subdeltoid bursa. Multiple rice bodies showed slightly high signal intensity of T1WI and T2WI, and no enhancement after gadolinium injection. (author). 7 refs., 4 figs.
9. Association between rotating night shift work and metabolic syndrome in Korean workers: differences between 8-hour and 12-hour rotating shift work.
Science.gov (United States)
Oh, Jae-Il; Yim, Hyeon Woo
2017-10-19
This study aimed to analyze the association between the shift work schedule and metabolic syndrome (MetS). This is a retrospective longitudinal study based on the 2015 health checkup data of 2,090 workers evaluated for MetS in 2010 at a general hospital in Korea. The participants were divided according to their shift work schedule into daytime, three-shift (8-hour rotation), and two-shift (12-hour rotation) workers. The index that indicates the association between the shift work schedule and MetS is the odds ratio (OR) calculated using multivariate logistic regression. The analysis for the entire group of workers indicated that there was positive association between two-shift rotation and MetS (OR=1.58, 95% confidence interval [CI]: 1.09, 2.29). In the analysis of rotating night-shift workers, the years of rotating night shifts, frequency of night-shift work, and sleep disturbance were added to the confounding variables, and two-shift work remained positively associated with MetS (OR=1.72, 95% CI: 1.10, 2.70). The risk of MetS differs based on the shift work schedules they engage in. Hence, structural changes to the shift work schedules are required to prevent MetS in night-shift workers.
10. The activity pattern of shoulder muscles in subjects with and without subacromial impingement
DEFF Research Database (Denmark)
Diederichsen, Louise Pyndt; Nørregaard, Jesper; Dyhre-Poulsen, Poul
2009-01-01
Altered shoulder muscle activity is frequently believed to be a pathogenetic factor of subacromial impingement (SI) and therapeutic interventions have been directed towards restoring normal motor patterns. Still, there is a lack of scientific evidence regarding the changes in muscle activity...... in patients with SI. The aim of the study was to determine and compare the activity pattern of the shoulder muscles in subjects with and without SI. Twenty-one subjects with SI and 20 healthy controls were included. Electromyography (EMG) was assessed from eight shoulder muscles from both shoulders during...... and serratus anterior muscles on the symptomatic side compared to the healthy subjects. On the asymptomatic side, the groups showed different muscle activity during external rotation. Our findings of an altered shoulder muscle activity pattern on both the symptomatic and asymptomatic side in patients indicate...
11. Glenohumeral and scapulothoracic strength impairments exists in patients with subacromial impingement, but these are not reflected in the shoulder pain and disability index.
Science.gov (United States)
Clausen, M B; Witten, A; Holm, K; Christensen, K B; Attrup, M L; Hölmich, P; Thorborg, K
2017-07-17
Pain and loss of function are cardinal symptoms associated with Subacromial impingement syndrome (SIS), while the presence and magnitude of deficits in strength and range of motion (ROM) are largely undescribed in non-athletic patients with SIS. Moreover, the relevance of impairments in strength and ROM to patient-reported shoulder function is not well described, even though testing of strength is recommended in clinical guidelines. The purpose of this study was, first, to investigate impairments in glenohumeral and scapulothoracic strength and in abduction and internal rotation ROM in patients with SIS. Secondly, to investigate the influence of these impairments on patient-reported shoulder function. Cross-sectional study based on a consecutive cohort of 157 patients referred to specialist examination and diagnosed with shoulder impingement (SIS) using predefined validated diagnostic criteria. Prior to specialist examination, questionnaires regarding shoulder function (Shoulder Pain And Disability Index, SPADI) demographics and kinesiophobia (TSK-11) were collected, and shoulder strength and ROM was measured by trained testers, with the patient reporting pain levels during testing and for the last week. Impairments in strength (abduction, external-rotation, (protraction and horizontal-extension) and ROM (abduction and internal rotation) were investigated in patients with unilateral shoulder pain, using one-sample t-tests. SPADI total score (SPADI) and SPADI function score (SPADI-F), were chosen as dependent variables in multiple regressions to investigate the influence of impairments on patient-reported shoulder function. Independent variables of interest were; strength in abduction and external rotation, abduction ROM, pain-during-tests, pain-last-week and kinesiophobia. Significant impairments were found for all impairment tests, but most pronounced for glenohumeral strength and abduction ROM (29-33% deficits), and less for scapulothoracic strength and internal
12. Subdeltoid/subacromial bursitis associated with influenza vaccination
OpenAIRE
Cook, Ian F
2013-01-01
A 76-year-old male presented with subacromial/subdeltoid bursitis following influenza vaccine administration into the left deltoid muscle. This shoulder injury related to vaccine administration (SIRVA) could have been prevented by the use of a safe, evidence based protocol for the intramuscular injection of the deltoid muscle.
13. Arthroscopic treatment of bony loose bodies in the subacromial space.
Science.gov (United States)
Li, Wei; Xiao, De-Ming; Jiang, Chang-Qing; Zhang, Wen-Tao; Lei, Ming
2015-01-01
Multiple bony loose bodies in the subacromial space caused form cartilage or bone cells and continue to grow. A 58-year-old man with two-year history of swelling and pain of the right shoulder. He had no history of tuberculosis and rheumatoid arthritis. Magnetic resonance (MR) images showed some bony loose bodies in the subacromial space. The removal of loose bodies and bursa debridement were performed arthroscopically. Histological diagnosis of them was synovitis with fibrous bodies. Extra-articular loose bodies is extremely rare, especially in the subacromial space, which maybe originated in the proliferative synovial bursa. Most authors recommend open removal to relive the pain, but there were choice to apply arthroscopy to remove them. The mechanism of formation of bony loose bodies is not clear, may be associated with synovial cartilage metaplasia. Arthroscopic removal of loose bodies and bursa debridement is a good option for treatment of the loose body in the subacromial space, which can receive good function. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
14. Subdeltoid/subacromial bursitis associated with influenza vaccination.
Science.gov (United States)
Cook, Ian F
2014-01-01
A 76-year-old male presented with subacromial/subdeltoid bursitis following influenza vaccine administration into the left deltoid muscle. This shoulder injury related to vaccine administration (SIRVA) could have been prevented by the use of a safe, evidence based protocol for the intramuscular injection of the deltoid muscle.
15. Arthroscopic treatment of bony loose bodies in the subacromial space
Directory of Open Access Journals (Sweden)
Wei Li
2015-01-01
Conclusion: The mechanism of formation of bony loose bodies is not clear, may be associated with synovial cartilage metaplasia. Arthroscopic removal of loose bodies and bursa debridement is a good option for treatment of the loose body in the subacromial space, which can receive good function.
16. Does Subacromial Osteolysis Affect Shoulder Function after Clavicle Hook Plating?
Directory of Open Access Journals (Sweden)
Siwei Sun
2016-01-01
Full Text Available Purpose. To evaluate whether subacromial osteolysis, one of the major complications of the clavicle hook plate procedure, affects shoulder function. Methods. We had performed a retrospective study of 72 patients diagnosed with a Neer II lateral clavicle fracture or Degree-III acromioclavicular joint dislocation in our hospital from July 2012 to December 2013. All these patients had undergone surgery with clavicle hook plate and were divided into two groups based on the occurrence of subacromial osteolysis. By using the Constant-Murley at the first follow-up visit after plates removal, we evaluated patients’ shoulder function to judge if it has been affected by subacromial osteolysis. Results. We have analyzed clinical data for these 72 patients, which shows that there is no significant difference between group A (39 patients and group B (33 patients in age, gender, injury types or side, and shoulder function (the Constant-Murley scores are 93.38±3.56 versus 94.24±3.60, P>0.05. Conclusion. The occurrence of subacromial osteolysis is not rare, and also it does not significantly affect shoulder function.
17. Does Subacromial Osteolysis Affect Shoulder Function after Clavicle Hook Plating?
Science.gov (United States)
Sun, Siwei; Gan, Minfeng; Sun, Han; Wu, Guizhong; Yang, Huilin; Zhou, Feng
2016-01-01
To evaluate whether subacromial osteolysis, one of the major complications of the clavicle hook plate procedure, affects shoulder function. We had performed a retrospective study of 72 patients diagnosed with a Neer II lateral clavicle fracture or Degree-III acromioclavicular joint dislocation in our hospital from July 2012 to December 2013. All these patients had undergone surgery with clavicle hook plate and were divided into two groups based on the occurrence of subacromial osteolysis. By using the Constant-Murley at the first follow-up visit after plates removal, we evaluated patients' shoulder function to judge if it has been affected by subacromial osteolysis. We have analyzed clinical data for these 72 patients, which shows that there is no significant difference between group A (39 patients) and group B (33 patients) in age, gender, injury types or side, and shoulder function (the Constant-Murley scores are 93.38 ± 3.56 versus 94.24 ± 3.60, P > 0.05). The occurrence of subacromial osteolysis is not rare, and also it does not significantly affect shoulder function.
18. Migration of calcium deposits into subacromial-subdeltoid bursa and into humeral head as a rare complication of calcifying tendinitis: sonography and imaging.
Science.gov (United States)
Della Valle, Valeria; Bassi, Emilio Maria; Calliada, Fabrizio
2015-09-01
Calcifying tendinitis of the shoulder is a common condition characterized by the deposition of calcium, predominantly hydroxyapatite crystals, in the rotator cuff. A rare complication of this condition is the migration of calcium deposits from tendons, usually the supraspinatus, into the subacromial-subdeltoid bursa or into the humeral greater tuberosity. These complications are responsible for intense acute shoulder pain and functional disability. Patient anamnesis and clinical symptoms must be considered to make the diagnosis, but imaging, particularly sonography, is often necessary, showing a typical presentation related to the locations of calcium deposits. We present sonographic and other imaging features of subacromial-subdeltoid bursitis and humeral osteitis related to the migration of calcium.
19. Case study of physiotherapy treatment of a patient after arthroscopic for subacromial decompression
OpenAIRE
Hiršová, Pavlína
2013-01-01
Title: Case study of physiotherapy treatment of a patient after arthroscopic for subacromial decompression The objective of this bachelor thesis is introduction with theme of physiotherapy of shoulder joint after arthroscopy for subacromial decompression. The thesis is divided in two main parts. The first (general) part describes anatomy, kinesiology and biomechanics of shoulder girdle briefly. There is also the reference of pathology in subacromial space and arthroscopic method description. ...
20. Arthroscopic treatment for synovial chondromatosis of the subacromial bursa: a case report.
Science.gov (United States)
Park, Jung Ho; Noh, Haeng Kee; Bada, Leela P; Wang, Joon Ho; Park, Jong Woong
2007-10-01
Synovial chondromatosis of the subacromial bursa has been reported rarely. To the best of our knowledge, there was no case report of arthroscopic treatment for synovial chondromatosis of the subacromial bursa in English literature. The authors present a case of synovial chondromatosis of the subacromial space in a 45-year-old male, which was managed by arthroscopy. This rare condition can be well managed on similar lines as the other joints through arthroscopic surgery.
1. A specific exercise strategy reduced the need for surgery in subacromial pain patients.
Science.gov (United States)
Hallgren, Hanna C Björnsson; Holmgren, Theresa; Oberg, Birgitta; Johansson, Kajsa; Adolfsson, Lars E
2014-10-01
A programme based on eccentric exercises for treating subacromial pain was in a previous study found effective at 3-month follow-up. The purposes of the present study were to investigate whether the results were maintained after 1 year and whether the baseline Constant-Murley score, rotator cuff status and radiological findings influenced the outcome. 97 patients on the waiting list for arthroscopic subacromial decompression had been randomised to a specific exercise programme or unspecific exercises (controls). After 3 months of exercises, the patients were asked whether they still wanted surgery and this option was available until a 1-year follow-up. 1 year after inclusion or 1 year after surgery, the number of patients who decided to have surgery in each group was compared. The choice of surgery was related to the baseline Constant-Murley score, ultrasound and radiographs taken at inclusion. All patients had improved significantly (p<0.0001) in the Constant-Murley score at the 1-year follow-up. Significantly more patients in the control group decided to have surgery (63%) than those in the specific exercise group (24%; p<0.0001). Patients who decided to have surgery had a significantly lower baseline Constant-Murley score and more often a full-thickness tear. Patients with partial tears did not differ from those with intact tendons. The positive short-term results of specific exercises were maintained after 1 year, and this exercise strategy reduces the need for surgery. Full-thickness tear and a low baseline Constant-Murley score appear to be a predictive marker for a less good outcome. Clinical trials NCT01037673. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
2. Comparison of risk factors for shoulder pain and rotator cuff syndrome in the working population.
Science.gov (United States)
Bodin, Julie; Ha, Catherine; Chastang, Jean-François; Descatha, Alexis; Leclerc, Annette; Goldberg, Marcel; Imbernon, Ellen; Roquelaure, Yves
2012-07-01
To compare risk factors for shoulder pain without and with rotator cuff syndrome (RCS). A total of 3,710 workers of a French region were randomly included in the cross-sectional study between 2002 and 2005. Personal and occupational risk factors were assessed during a physical examination and by a self-administered questionnaire. Multinomial logistic modeling was used for the following outcomes: no shoulder pain and no RCS (reference), shoulder pain without RCS (called "shoulder pain") and RCS, separately for men and women. The prevalence rates of "shoulder pain" for men and women were 28.0% and 31.1%, respectively, and the prevalence rates of RCS were 6.6% and 8.5%, respectively. In men, "shoulder pain" and RCS were associated with age, high-perceived physical exertion, and arm abduction. Automatic work pace and low supervisor support were associated with "shoulder pain," and high psychological demand and low skill discretion with RCS. In women, "shoulder pain" and RCS were associated with age, repetitiveness of tasks, and low supervisor support. High perceived physical exertion and exposure to cold temperatures were associated with "shoulder pain." Age was more strongly associated with RCS than with shoulder pain without RCS for both genders. Biomechanical and psychosocial factors were associated with "shoulder pain" and RCS and differed between genders. Copyright © 2011 Wiley Periodicals, Inc.
3. Subacromial bursitis following human papilloma virus vaccine misinjection.
Science.gov (United States)
Uchida, Soshi; Sakai, Akinori; Nakamura, Toshitaka
2012-12-17
A patient presented at our clinic with severe subacromial bursitis, which persisted for several months following a third booster injection with Cervarix™. Chronic subacromial bursitis manifested itself in this patient after what appeared to be the misinjection of vaccine in close proximity to the acromion. This bursitis was resistant to conventional physiotherapy and to corticosteroid therapy, but was responsive to arthroscopic surgery. Since such patients may present to an arthroscopic surgeon only months after receiving a vaccine injection, this etiological link may not be fully appreciated by treating clinicians. Further, the accuracy of injection in the deltoid region also appears under appreciated, and this report highlights the importance of accurate injection to the deltoid region or in certain cases, the value of simply changing the injection site to another larger muscle. Copyright © 2012 Elsevier Ltd. All rights reserved.
4. Huge tumor-like subacromial bursitis associated with rheumatoid arthritis.
Science.gov (United States)
Yoneda, M; Wakitani, S; Yamamoto, T
2001-09-01
Abstract We report a rare case of a huge subacromial bursitis in rheumatoid arthritis. A solid tumor was initially suspected because it was very large with no apparent local sign of inflammation, and because no fluid retention was observed. We performed radiograms, a plain computed tomogram, a (99)mTc-MDP bone scintigram, a (67)Ga-citrate scintigram, and a digital subtraction arteriogram, which all indicated no evidence of tumor. Finally, a bursogram proved the mass to be a huge enlarged subacromial bursa. Surgical exploration revealed that the bursa contained 450 g of a yellowish, jelly-like substance, which was considered to be a thick collection of fibrin. No recurrence was noted at a follow-up 16 years after surgery.
5. Subacromial space in adult patients with thoracic hyperkyphosis and in healthy volunteers.
Science.gov (United States)
Gumina, Stefano; Di Giorgio, Giantony; Postacchini, Franco; Postacchini, Roberto
2008-02-01
The assumption that subacromial space decreases in patients with thoracic hyperkyphosis arises from sporadic and personal observations. The purpose of this study was to compare width of subacromial space calculated on radiographs and CT scans of a high number of patients with thoracic hyperkyphosis that registered on exams of healthy volunteers. We measured the subacromial space, using Petersson's method, on radiographs of 47 patients with idiopathic or acquired thoracic hyperkyphosis and of 175 healthy shoulder volunteers. Both groups were further distinguished considering gender and age. Females with hyperkyphosis were also divided in two subgroups: those with a kyphotic curve of less (24 patients) or more (19 patients) than 50 degrees , respectively. Subacromial space of all patients and of 21 volunteers was also evaluated using CT. Acromio-humeral space was less wide in patients with hyperkyphosis with respect to coeval volunteers of the same gender; in females and in subjects older than 60. Subacromial width of females with hyperkyphosis whose curve was more than 50 degrees was significantly narrower (phyperkyphosis greater than 50 degrees had a subacromial space narrower than that measured in patients with a less severe kyphosis. This suggests that subacromial width is directly related to severity of thoracic kyphosis. Because hyperkyphosis of patients with osteoporotic vertebral fractures may worsen over the time, subacromial decompression could give only temporary shoulder pain relief.
6. Targeted knockout of TNF-α by injection of lentivirus-mediated siRNA into the subacromial bursa for the treatment of subacromial bursitis in rats.
Science.gov (United States)
Wang, Yi; Li, Quan; Wei, Xianzhao; Xu, Jie; Chen, Qi; Song, Shuang; Lu, Zhe; Wang, Zimin
2015-09-01
Subacromial bursitis (SAB) is the major source of pain in rotator cuff disease. Although multiple investigations have provided support for the role of inflammatory cytokines in SAB, few have focussed on the use these cytokines in the treatment of SAB. The aim of the present study was to observe the therapeutic efficacy of lentivirus‑mediated RNA interference (RNAi) on carrageenan‑induced SAB by injecting lentivirus‑tumor necrosis factor (TNF)‑α‑RNAi expressing TNF‑α small interfering (si)RNA. Using screened siRNA segments, an siRNA was designed. A lentivirus vector expressing siRNA was established and packed as lentivirus particles. A lentivirus that expressed the negative sequence was used as a lentivirus‑negative control (NC). The carrageenan‑induced SAB model was established in 32 male Sprague‑Dawley rats. The modeled rats were randomly assigned to four groups: Lentivirus‑RNAi treatment group, lentivirus‑NC group, SAB group and phosphate‑buffered saline (PBS) blank control group. The lentivirus was injected (1x10(7) transducing units) into the subacromial bursa of the rats in the lentivirus‑RNAi group and lentivirus‑NC group, whereas 100 µl PBS was injected at the same site in the SAB group and the PBS blank control group. At 5 weeks following injection, the animals were sacrificed and venous blood was obtained. The effect of TNF‑α interference and the expression of inflammatory cytokines were determined by reverse transcription‑quantitative polymerase chain reaction, western blotting, hematoxylin and eosin staining, Van Gieson's staining and immunofluorescence. The expression of TNF‑α was decreased in the lentivirus‑TNF‑α‑RNAi group compared with that in the SAB group. Morphological observations revealed that the number of inflammatory cells were reduced and damage to tendon fibers was attenuated in this group, suggesting that the downregulation of the protein expression levels of TNF‑α‑associated nuclear
7. Isolation and characterization of human mesenchymal stem cells derived from shoulder tissues involved in rotator cuff tears.
Science.gov (United States)
Utsunomiya, Hajime; Uchida, Soshi; Sekiya, Ichiro; Sakai, Akinori; Moridera, Kuniaki; Nakamura, Toshitaka
2013-03-01
Recent studies report a relatively high failure rate for tendon-bone healing after rotator cuff repair. Several studies have investigated biologically augmented rotator cuff repair; however, none has shown the application of synovial mesenchymal stem cells for such repair. To demonstrate whether cells derived from shoulder tissues have mesenchymal stem cell properties and to identify which tissue is the best source of the mesenchymal stem cells. Controlled laboratory study. Forty-two patients with a diagnosed rotator cuff tear preoperatively were enrolled in this study. Human mesenchymal tissues were obtained during arthroscopic surgery for rotator cuff tears from 19 donors who met the inclusion criteria and had investigable amounts of tissue. Colony-forming units, yield obtained, expandability, differentiation potential, epitope profile, and gene expression were compared among the cells from 4 shoulder tissues: synovium of the glenohumeral joint, subacromial bursa, margin of the ruptured supraspinatus tendon, and residual tendon stump on the greater tuberosity (enthesis). The number of live passage 0 cells from whole tissue was significantly higher in cells derived from the subacromial bursa (P source. The findings indicate that the subacromial bursa is a good candidate for the source of mesenchymal stem cells in rotator cuff tears. Synovial cells from the subacromial bursa in patients with rotator cuff tears are a superior cell source in vitro, suggesting that mesenchymal stem cells from this tissue could be good candidates for biological augmentation of rotator cuff repair.
8. Is ultrasound-guided injection more effective in chronic subacromial bursitis?
Science.gov (United States)
Hsieh, Lin-Fen; Hsu, Wei-Chun; Lin, Yi-Jia; Wu, Shih-Hui; Chang, Kae-Chwen; Chang, Hsiao-Lan
2013-12-01
Although ultrasound (US)-guided subacromial injection has shown increased accuracy in needle placement, whether US-guided injection produces better clinical outcome is still controversial. Therefore, this study aimed to compare the efficacy of subacromial corticosteroid injection under US guidance with palpation-guided subacromial injection in patients with chronic subacromial bursitis. Patients with chronic subacromial bursitis were randomized to a US-guided injection group and a palpation-guided injection group. The subjects in each group were injected with a mixture of 0.5 mL dexamethasone suspension and 3 mL lidocaine into the subacromial bursa. The primary outcome measures were the visual analog scale for pain and active and passive ranges of motion of the affected shoulder. Secondary outcome measures were the Shoulder Pain and Disability Index, the Shoulder Disability Questionnaire, and the 36-item Short-Form Health Survey (SF-36). The primary outcome measures were evaluated before, immediately, 1 wk, and 1 month after the injection; the secondary outcome measures were evaluated before, 1 wk, and 1 month after the injection. Of the 145 subjects screened, 46 in each group completed the study. Significantly greater improvement in passive shoulder abduction and in physical functioning and vitality scores on the SF-36 were observed in the US-guided group. The pre- and postinjection within-group comparison revealed significant improvement in the visual analog scale for pain and range of motion, as well as in the Shoulder Pain and Disability Index, Shoulder Disability Questionnaire, and SF-36 scores, in both groups. The US-guided subacromial injection technique produced significantly greater improvements in passive shoulder abduction and in some items of the SF-36. US is effective in guiding the needle into the subacromial bursa in patients with chronic subacromial bursitis.
9. Alternativas terapéuticas en el manejo del Síndrome Subacromial: Cross Taping
OpenAIRE
Dizy-Friera, Eduardo
2015-01-01
El síndrome subacromial, también conocido como síndrome de pinzamiento del hombro, es un trastorno muy prevalente en nuestra sociedad que genera un alto coste socioeconómico y una elevada discapacidad. El síndrome subacromial supone un desafío terapéutico para los fisioterapeutas. Existen múltiples formas de tratamiento, sin embargo la evidencia científica que las apoya es escasa. El propósito de este estudio es evaluar la efectividad del cross taping en el síndrome subacromial, incluyendo...
10. Subacromial corticosteroid injections transiently decrease suture anchor pullout strength: biomechanical studies in rats.
Science.gov (United States)
Dolkart, Oleg; Chechik, Ofir; Bivas, Assaf; Brosh, Tamar; Drexler, Michael; Weinerman, Zachary; Maman, Eran
2017-10-01
Arthroscopic rotator cuff (RC) repair incorporates suture anchors to secure torn RC tendons to the greater tuberosity (GT) bone. RC repair strength depends on the anchor-bone interface and on the quality of the GT. We evaluated the effect of single and multiple corticosteroid injections on the pullout strength of suture anchors. Fifty rats were divided into those receiving saline solution injection (control group), a single methylprednisolone acetate (MTA) injection (MTA1 group), or 3 once-weekly MTA injections (MTA3 group). Rats were killed humanely at 1 or 4 weeks after the last injection. A mini-suture anchor was inserted into the humeral head through the GT. Specimens were tested biomechanically. At 1 week after the last injection, the mean maximal pullout strength was significantly reduced in the MTA1 group (63.5%) and MTA3 group (56%) compared with the control group (P suture anchor at 1 week. However, this effect was transient and resolved within a relatively short period. These findings indicate that a waiting period is required between subacromial corticosteroid injection and RC repair surgery that involves the use of suture anchors. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
11. Association of Bicipital Peritendinous Effusion with Subacromial Impingement: A Dynamic Ultrasonographic Study of 337 Shoulders
OpenAIRE
Ke-Vin Chang; Wei-Ting Wu; Levent Özçakar
2016-01-01
Bicipital peritendinous effusion (BPE) is the most common biceps tendon abnormality and can be related to various shoulder ultrasonographic findings. Since the association of BPE with subacromial impingement is unclear, our study aimed to explore its association with the dynamic subacromial impingement test during ultrasound (US) imaging. We included 337 shoulders referred for US examinations and quantified the amount of BPE. Effusion more than 1?mm in thickness was considered a positive find...
12. Clinical and radiological outcome of conservative vs. surgical treatment of atraumatic degenerative rotator cuff rupture: design of a randomized controlled trial
Directory of Open Access Journals (Sweden)
van den Akker-Scheek Inge
2011-01-01
Full Text Available Abstract Background Subacromial impingement syndrome is a frequently observed disorder in orthopedic practice. Lasting symptoms and impairment may occur when a subsequent atraumatic rotator cuff rupture is also present. However, degenerative ruptures of the rotator cuff can also be observed in asymptomatic elderly individuals. Treatment of these symptomatic degenerative ruptures may be conservative or surgical. Acceptable results are reported for both treatment modalities. No evidence-based level-1 studies have been conducted so far to compare these treatment modalities. The objective of this study is to determine whether there is a difference in outcome between surgical reconstruction and conservative treatment of a degenerative atraumatic rotator cuff tendon rupture. Methods/Design A randomized controlled trial will be conducted. Patients aged between 45 and 75 with a symptomatic atraumatic rotator cuff rupture as diagnosed by MRI will be included. Exclusion criteria are traumatic rotator cuff rupture, frozen shoulder and diabetes mellitus. Patients will be randomized into two groups. Conservative treatment includes physical therapy according to a standardized protocol, NSAIDs and, if indicated, subacromial infiltration with a local anesthetic and corticosteroids. Surgical reconstruction is performed under general anesthesia in combination with an interscalenus plexus block. An acromioplasty with reconstruction of the rotator cuff tendon is performed, as described by Rockwood et al. Measurements take place preoperatively and 6 weeks, 3 months, 6 months and 1 year postoperatively. The primary outcome measure is the Constant score. Secondary measures include both disease-specific and generic outcome measures, and an economic evaluation. Additionally, one year after inclusion a second MRI will be taken of all patients in order to determine whether extent and localization of the rupture as well as the amount of fatty degeneration are prognostic
13. Shoulder Impingement Syndromes: Implications on Physical Therapy Examination and Intervention
Science.gov (United States)
2005-01-01
A painful shoulder presents challenges in examination, diagnosis and intervention for the physical therapist because of the complexity of the structures involved. A common cause of shoulder pain is shoulder impingement syndrome. This was first described as a condition in which the soft tissues of the subacromial space were chronically entrapped and compressed between the humeral head and the subacromial arch. This definition does not account for the myriad potential causes of shoulder impingement conditions, as forms of impingement other than subacromial soft tissue compression may explain different symptomatic shoulder injuries. This paper describes shoulder impingement syndromes that have been hypothesized, identified and analyzed in the literature. Physical Therapy examination and intervention for these syndromes are also discussed. PMID:25792938
14. Joint position sense is not altered during shoulder medial and lateral rotations in female assembly line workers with shoulder impingement syndrome.
Science.gov (United States)
Haik, Melina N; Camargo, Paula R; Zanca, Gisele G; Alburquerque-Sendín, Francisco; Salvini, Tania F; Mattiello-Rosa, Stela M
2013-01-01
This study evaluated joint position sense (JPS) during medial and lateral rotations of the shoulder in female workers with and without shoulder impingement syndrome (SIS). Three groups were assessed. The case group consisted of 15 female assembly line workers (35.5, SD 5.8 years) with unilateral SIS. Control group 1 consisted of 15 female assembly line workers asymptomatic for SIS (34.4, SD 5.5 years) and control group 2 consisted of 15 female subjects (33.1, SD 6.2 years) asymptomatic for SIS and with no exposure to activities with the upper limbs. The JPS was evaluated bilaterally during passive (2°/sec) and active (5°/sec) repositioning tests using an isokinetic dynamometer. The target angles were 45° of lateral rotation (achieved by medially rotating the shoulder from 90° of lateral rotation) and 75° of lateral rotation (achieved by laterally rotating the shoulder from neutral rotation). There were no differences between sides for all groups (p > 0.05). There were no differences in any of the variables between the case group and the control groups (p > 0.05). The results of this study suggest that JPS during medial and lateral rotations of the shoulder is not altered in female assembly line workers with SIS.
15. Impingement syndrome of the ankle following supination external rotation trauma: MR imaging findings with arthroscopic correlation
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Schaffler, Gottfried J. [Department of Radiology, University of California San Francisco, 350 Parnassus Avenue, Suite 150, San Francisco, CA 94117 (United States); Department of Radiology, University Hospital Graz, Auenbruggerplatz 9, 8036 Graz (Austria); Tirman, Phillip F.J.; Stoller, David W. [San Francisco Magnetic Resonance Center, 3333 California Street, Suite 105, San Francisco, CA 94118 (United States); Genant, Harry K. [Department of Radiology, University of California San Francisco, 350 Parnassus Avenue, Suite 150, San Francisco, CA 94117 (United States); Ceballos, Cecar; Dillingham, Michael F. [Sports Orthopedics and Rehabilitation, 2884 Sand Hill Rd., Suite 110, Menlo Park, CA 94025 (United States)
2003-06-01
Our objective was to identify MR imaging findings in patients with syndesmotic soft tissue impingement of the ankle and to investigate the reliability of these imaging characteristics to predict syndesmotic soft tissue impingement syndromes of the ankle. Twenty-one ankles with chronic pain ultimately proven to have anterior soft tissue impingement syndrome were examined by MR imaging during January 1996 to June 2001. The MR imaging protocol included sagittal and coronal short tau inversion recovery (STIR), sagittal T1-weighted spin echo, axial and coronal proton-density, and T2-weighted spin-echo sequences. Nineteen ankles that underwent MR imaging during the same period of time and that had arthroscopically proven diagnosis different than impingement syndrome served as a control group. Fibrovascular scar formations distinct from the syndesmotic ligaments possibly related to syndesmotic soft tissue impingement were recorded. Arthroscopy was performed subsequently in all patients and was considered the gold standard. The statistical analysis revealed an overall frequency of scarred syndesmotic ligaments of 70% in the group with ankle impingement. Fibrovascular scar formations distinct from the syndesmotic ligaments presented with low signal intensity on T1-weighted images and remained low to intermediate in signal intensity on T2-weighted MR imaging. Compared with arthroscopy, MR imaging revealed a sensitivity of 89%, a specificity of 100%, and a diagnostic accuracy of 93% for scarred syndesmotic ligaments. The frequency of scar formation distinct from the syndesmotic ligaments in patients with impingement syndrome of the ankle was not statistically significantly higher than in the control group. In contrast to that, anterior tibial osteophytes and talar osteophytes were statistically significantly higher in the group with anterior impingement than in the control group. Conventional MR imaging was found to be insensitive for the diagnosis of syndesmotic soft tissue
16. The influence of induced shoulder muscle pain on rotator cuff and scapulothoracic muscle activity during elevation of the arm.
Science.gov (United States)
Castelein, Birgit; Cools, Ann; Parlevliet, Thierry; Cagnie, Barbara
2017-03-01
Altered recruitment of rotator cuff and scapulothoracic muscles has been identified in patients with subacromial impingement syndrome. To date, however, the cause-consequence relationship between pain and altered muscle recruitment has not been fully unraveled. The effect of experimental shoulder pain induced by injection of hypertonic saline in the supraspinatus on the activity of the supraspinatus, infraspinatus, subscapularis, trapezius, and serratus anterior activity was investigated during the performance of an elevation task by use of muscle functional magnetic resonance imaging in 25 healthy individuals. Measurements were taken at 4 levels (C6-C7, T2-T3, T3-T4, and T6-T7) at rest and after the elevation task performed without and with experimental shoulder pain. During arm elevation, experimentally induced pain caused a significant activity reduction, expressed as reduction in T2 shift of the IS (P = .029). No significant changes in T2 shift values were found for the other rotator cuff muscles or the scapulothoracic muscles. This study demonstrates that acute experimental shoulder pain has an inhibitory effect on the activity of the IS during arm elevation. Acute experimental shoulder pain did not seem to influence the scapulothoracic muscle activity significantly. The findings suggest that rotator cuff muscle function (infraspinatus) should be a consideration in the early management of patients with shoulder pain. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
17. Intra-rater and inter-rater reliability of the standardized ultrasound protocol for assessing subacromial structures
DEFF Research Database (Denmark)
Hougs Kjær, Birgitte; Ellegaard, Karen; Wieland, Ina
2017-01-01
: To investigate the intra- and inter-rater reliability of the existing ultrasound (US) examinations of the subacromial space, the subacromial-subdeltoid bursa, and the supraspinatus tendon. METHOD: In a three-phased design, two physiotherapists using a standardized US protocol examined the thickness...
18. Association of Bicipital Peritendinous Effusion with Subacromial Impingement: A Dynamic Ultrasonographic Study of 337 Shoulders.
Science.gov (United States)
Chang, Ke-Vin; Wu, Wei-Ting; Özçakar, Levent
2016-12-12
Bicipital peritendinous effusion (BPE) is the most common biceps tendon abnormality and can be related to various shoulder ultrasonographic findings. Since the association of BPE with subacromial impingement is unclear, our study aimed to explore its association with the dynamic subacromial impingement test during ultrasound (US) imaging. We included 337 shoulders referred for US examinations and quantified the amount of BPE. Effusion more than 1 mm in thickness was considered a positive finding. A comparison of three grades of subacromial impingement, adjusted by patient demographics, static sonographic shoulder pathology, and physical findings, by using multivariate regression models revealed that the odds ratio of subacromial impingement (with 95% confidence intervals) in the presence of BPE was 6.54 (3.21-13.32) in grade 1, 6.93 (3.05-15.76) in grade 2 and 3.18 (1.48-6.80) in grade 3. An increase in age, subdeltoid bursitis, full-thickness supraspinatus tendon tear, and shoulder stiffness were also associated with BPE. Since our study demonstrated a positive association of BPE with all grades of impingement, a US dynamic subacromial impingement test is suggested when BPE is present. Future prospective studies are needed to identify changes in BPE after treatment.
19. Inflammatory cytokines are overexpressed in the subacromial bursa of frozen shoulder.
Science.gov (United States)
Lho, Yun-Mee; Ha, Eunyoung; Cho, Chul-Hyun; Song, Kwang-Soon; Min, Byung-Woo; Bae, Ki-Cheor; Lee, Kyung-Jae; Hwang, Ilseon; Park, Hyung-Bin
2013-05-01
Frozen shoulder is a debilitating condition characterized by gradual loss of glenohumeral motion with chronic inflammation and capsular fibrosis. Yet its pathogenesis remains largely unknown. We hypothesized that the subacromial bursa may be responsible for the pathogenesis of frozen shoulder by producing inflammatory cytokines. We obtained joint capsules and subacromial bursae from 14 patients with idiopathic frozen shoulder and from 7 control subjects to determine the expression levels of interleukin (IL) 1α, IL-1β, IL-6, tumor necrosis factor α (TNF-α), cyclooxygenase (COX) 1, and COX-2 by real-time reverse transcriptase-polymerase chain reaction, immunohistochemistry, and enzyme-linked immunosorbent assay. IL-1α, IL-1β, TNF-α, COX-1, and COX-2 were expressed at significantly high levels in the joint capsules of the frozen shoulder group compared with those of the control group. Intriguingly, IL-1α, TNF-α, and COX-2 were also expressed at significantly high levels in the subacromial bursae of the frozen shoulder group compared with those of the control group. Immunohistochemical analysis showed increased expression of COX-2 in both the joint capsules and subacromial bursae of the frozen shoulder group. These findings imply that elevated levels of inflammatory cytokines in the subacromial bursa may be associated with the pathogenesis of inflammation evolving into fibrosis. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.
20. Secondary Subacromial Impingement after Valgus Closing-Wedge Osteotomy for Proximal Humerus Varus
Directory of Open Access Journals (Sweden)
Hirotaka Sano
2015-01-01
Full Text Available A 31-year-old construction worker had been suffering from both the motion pain and the restriction of elevation in his right shoulder due to severe varus deformity of humeral neck, which occurred after proximal humeral fracture. The angle for shoulder flexion and abduction was restricted to 50 and 80 degrees, respectively. Valgus closing-wedge osteotomy followed by the internal fixation using a locking plate was carried out at 12 months after injury. Postoperatively, the head-shaft angle of the humerus improved from 65 to 138 degrees. Active flexion and abduction angles improved from 80 to 135 degrees and from 50 to 135 degrees, respectively. However, the patient complained from a sharp pain with a clicking sound during shoulder abduction even after removal of the locking plate. Since subacromial steroid injection temporarily relieved his shoulder pain, we assumed that the secondary subacromial impingement was provoked after osteotomy. Thus, arthroscopic subacromial decompression was carried out at 27 months after the initial operation, which finally relieved his symptoms. In the valgus closing-wedge osteotomy, surgeons should pay attention to the condition of subacromial space to avoid causing the secondary subacromial impingement.
1. Subacromial bursitis with giant rice bodies as initial presentation of rheumatoid arthritis.
Science.gov (United States)
Subramaniam, Ramesh; Tan, Justina Wei Lyn; Chau, Cora Yuk Ping; Lee, Keng Thiam
2012-10-01
Rice body formation is a nonspecific response to chronic synovial inflammation associated with tuberculous arthritis, rheumatoid arthritis, juvenile rheumatoid arthritis, seronegative inflammatory arthritis, and even osteoarthritis. Such bodies were termed rice bodies because of their close resemblance to grains of polished white rice. We present a case report of a middle-aged woman with right shoulder subacromial/subdeltoid bursitis with giant rice body formation as her initial presentation of rheumatoid arthritis. Her right shoulder symptoms resolved after subacromial and subdeltoid bursectomy and removal of the rice bodies. She subsequently developed inflammatory arthritis of other joints, met the criteria for rheumatoid arthritis, and has been treated medically.
2. Impingement syndrome of the shoulder; Schulterimpingement
Energy Technology Data Exchange (ETDEWEB)
Mayerhoefer, M.E. [Klinische Abteilung fuer Osteologie, Klinik fuer Radiodiagnostik der Universitaet Wien (Austria); Klinische Abteilung Radiodiagnostik fuer chirurgische Faecher, Klinik fuer Radiodiagnostik der Universitaet Wien (Austria); Klinische Abteilung fuer Osteologie, Klinik fuer Radiodiagnostik der Universitaet, Waehringer Guertel 18-20, 1090, Wien (Austria); Breitenseher, M.J. [Klinische Abteilung fuer Osteologie, Klinik fuer Radiodiagnostik der Universitaet Wien (Austria); Waldviertelklinikum Horn (Austria)
2004-06-01
The impingement syndrome is a clinical entity characterized by shoulder pain due to primary or secondary mechanical irritation of the rotator cuff. The primary factors for the development of impingement are a curved or hook-shaped anterior acromion as well as subacromial osteophytes, which may lead to tearing of the supraspinatus tendon. Secondary impingement is mainly caused by calcific tendinopathy, glenohumeral instability, os acromiale and degenerative changes of the acromioclavicular joint. Conventional radiographs are initially obtained, mainly for evaluation of the bony structures of the shoulder. If available, sonography can be used for detection of lesions and tears of the rotator cuff. Finally, MR-imaging provides detailed information about the relationship of the acromion and the acromioclavicular joint to the rotator cuff itself. In many cases however, no morphologic cause for impingement syndrome can be found. While patients are initially treated conservatively, chronic disease usually requires surgical intervention. (orig.) [German] Das Impingementsyndrom ist ein klinisches Krankheitsbild multifaktorieller Genese, bei dem es primaer oder sekundaer zu einer schmerzhaften mechanischen Beeintraechtigung der Rotatorenmanschette kommt. Als primaere Faktoren gelten ein gebogener oder hakenfoermiger Vorderrand des Akromions oder von diesem entspringende Osteophyten, was zu Laesionen der Supraspinatussehne fuehren kann. Zu den sekundaeren Faktoren zaehlt man v. a. eine Tendinitis calcarea, eine glenohumerale Instabilitaet, ein Os acromiale sowie degenerative Veraenderungen im Bereich des Akromioklavikulargelenks. Bildgebend steht an erster Stelle ein Nativroentgen, mit dem sich die knoechernen Strukturen gut darstellen lassen. Falls vorhanden, kann in weiterer Folge die Sonographie Auskunft ueber den Zustand der Rotatorenmanschette geben. Mit der MRT schliesslich laesst sich die Beziehung von Akromion und gelenkassoziierten Strukturen zur Rotatorenmanschette
3. Effects of the abdominal drawing-in maneuver on muscle activity, pelvic motions, and knee flexion during active prone knee flexion in patients with lumbar extension rotation syndrome.
Science.gov (United States)
Park, Kyue-Nam; Cynn, Heon-Seock; Kwon, Oh-Yun; Lee, Won-Hwee; Ha, Sung-Min; Kim, Su-Jung; Weon, Jong-Hyuck
2011-09-01
4. Subaxial rotational vertebral artery syndrome: resection of the uncinate process and anterior fusion can be sufficient!: case report and review of the literature.
Science.gov (United States)
Schelfaut, Sebastiaan; Verhasselt, Skrallan; Carpentier, Karel; Moke, Lieven
2015-03-01
A case report on rotational vertebral artery syndrome (RVAS) and surgical treatment. To illustrate a safe treatment option of RVAS with diminished risk of iatrogenic damage to the vertebral artery. RVAS is an uncommon cause of symptomatic transient vertebrobasilar insufficiency induced by physiological head rotation with temporary significant external compression of the dominant subaxial vertebral artery. Previous reports state that the treatment of choice consists of decompression of the vessel with resection of the anterior rim of the transverse process and any fibrotic sheet or intertransverse muscle, if necessary, combined with an anterior cervical discectomy and fusion (ACDF) with uncus resection. This is a case report on RVAS and its surgical treatment. The diagnosis of RVAS due to an osteophyte of the uncinate process at level C5/C6 was confirmed using computed tomographic angiography. We performed a classic ACDF using the contralateral approach with complete resection of the uncovertebral joint at the pathologic site. In our case, the symptoms of transient vertebrobasilar insufficiency induced by head rotation completely resolved postoperatively, and computed tomographic angiography images at 3 months postoperatively showed good bony ingrowth and restoration of vertebral artery patency during extreme rotation. Classic ACDF with complete resection of the uncovertebral joint is a safe treatment option for RVAS in the subaxial cervical spine. Fusion at the pathologic level will eliminate rotation and prevent further formation of osteophytes at the operated level. Unroofing of the vertebral artery seems not always necessary, diminishing the surgical risk.
5. Developmental changes in mental rotation ability and visual perspective-taking in children and adults with Williams Syndrome
Directory of Open Access Journals (Sweden)
Masahiro eHirai
2013-12-01
6. Subacromial corticosteroid injection for poststroke shoulder pain: an exploratory prospective case series.
Science.gov (United States)
Chae, John; Jedlicka, Lynn
2009-03-01
To assess the effectiveness of subacromial corticosteroid injections for poststroke shoulder pain. Exploratory, prospective case series. Ambulatory setting, university-affiliated hospital. Stroke survivors (N=10) with pain in the hemiparetic shoulder. Consecutive stroke survivors with evidence of supraspinatus impingement, supraspinatus tendonitis, or subacromial bursitis received subacromial corticosteroid injections. The primary outcome measure was the Brief Pain Inventory (BPI) question 12 (BPI 12), which assesses "worst pain" in the previous 7 days. Secondary measures included BPI question 15, which assesses present pain and BPI question 23 (BPI 23), which assesses pain interference with 7 daily activities. Outcomes were assessed at baseline, weekly for the first 4 weeks and then at 8 and 12 weeks postinjection. Repeated measure analysis of variance revealed significant within group time effect for BPI 12 (F=7.7, PSubacromial corticosteroid injection is associated with significant reduction in poststroke shoulder pain in patients with evidence of supraspinatus impingement, supraspinatus tendonitis, or subacromial bursitis. However, there is a gradual loss of effect with time. Controlled trials are needed to show a cause and effect relationship.
7. Ultrasound-guided shoulder injections in the treatment of subacromial bursitis.
Science.gov (United States)
Chen, Max J L; Lew, Henry L; Hsu, Tsz-Ching; Tsai, Wen-Chung; Lin, Wei-Ching; Tang, Simon F T; Lee, Ya-Chen; Hsu, Rex C H; Chen, Carl P C
2006-01-01
To investigate the treatment effectiveness between ultrasound-guided and blind injection techniques in the treatment of subacromial bursitis. A total of 40 patients with sonographic confirmation of subacromial bursitis were recruited into this study. These patients were divided into blind and ultrasound-guided injection groups. The shoulder abduction range of motion was compared before injections and 1 wk after the completion of injections in both groups. The shoulder abduction range of motion before injection in the blind injection group was 71.03 +/- 12.38 degrees and improved to 100 +/- 18.18 degrees 1 wk after the injection treatments. However, the improvement did not reveal significant statistical differences (P > 0.05). The shoulder abduction range of motion before injection in the ultrasound-guided injection group was 69.05 +/- 14.72 degrees and improved to 139.29 +/- 20.14 degrees 1 wk after the injection treatments (P subacromial bursa. The ultrasound-guided injection technique can result in significant improvement in shoulder abduction range of motion as compared with the blind injection technique in treating patients with subacromial bursitis.
8. Multiple rice body formation in chronic subacromial/subdeltoid bursitis: MR appearances.
Science.gov (United States)
Griffith, J F; Peh, W C; Evans, N S; Smallman, L A; Wong, R W; Thomas, A M
1996-07-01
Multiple rice body formation is an unusual complication of chronic bursitis. Clinically and macroscopically, it can resemble synovial osteochondromatosis. Radiographic and MR appearances, however, may allow an accurate pre-operative diagnosis. The imaging features of two middle-aged women with multiple subacromial/subdeltoid bursa rice bodies are described.
9. Septic subacromial bursitis caused by Mycobacterium kansasii in an immunocompromised host.
Science.gov (United States)
Mathew, Stephanie D; Tully, Charla C; Borra, Himabindu; Berven, Michael D; Arroyo, Ramon
2012-05-01
Mycobacterium kansasii is a common cause of pulmonary infection as a result of nontuberculous mycobacteria, but is less commonly described as a cause of an orthopedic infection. We present the first case of M. kansasii subacromial septic bursitis in an immunocompromised host. This case demonstrates the diagnostic and treatment challenges associated with orthopedic infections caused by M. kansasii.
10. Injection of the subacromial-subdeltoid bursa: blind or ultrasound-guided?
NARCIS (Netherlands)
Rutten, M.J.C.M.; Maresch, B.J.; Jager, G.J.; Waal Malefijt, M.C. de
2007-01-01
BACKGROUND: Blind injection of the subacromial-sub-deltoid bursa (SSB) for diagnostic purposes (Neer test) or therapeutic purposes (corticosteroid therapy) is frequently used. Poor response to previous blind injection or side effects may be due to a misplaced injection. It is assumed that ultrasound
11. Bilateral subacromial bursitis with macroscopic rice bodies: Ultrasound, CT and MR appearance
Energy Technology Data Exchange (ETDEWEB)
Law, T.C.; Chong, S.F.; Lu, P.P. [Kwong Wah Hospital (Hong Kong). Department of Radiology; Mak, K.H. [Kwong Wah Hospital (Hong Kong). Department of Orthopaedics and Traumatology
1998-05-01
The radiological findings of ultrasound, CT and MR of a case of bilateral subacromial bursitis with macroscopic rice bodies is described. MRI is the investigation of choice and the intravenous gadolinium-enhanced usefulness was noted. The previous literature is also reviewed. Copyright (1998) Blackwell Science Pty Ltd 5 refs., 1 tab., 4 figs.
12. Comparison of three types of exercise in the treatment of rotator cuff tendinopathy/shoulder impingement syndrome: A randomized controlled trial.
Science.gov (United States)
Heron, Stuart R; Woby, Steve R; Thompson, Dave P
2017-06-01
13. Acute effects of scapular Kinesio Taping® on shoulder rotator strength, ROM and acromiohumeral distance in asymptomatic overhead athletes.
Science.gov (United States)
Harput, Gulcan; Guney, Hande; Toprak, Ugur; Colakoglu, Filiz; Baltaci, Gul
2017-11-01
There is limited information in the literature that shows whether scapular taping has an effect on the acromiohumeral distance (AHD) and shoulder functions. The aim of this study was to investigate the acute effects of scapular Kinesio Taping® on shoulder internal rotation (IR) and external rotation (ER) strength, IR and ER range of motion (ROM) and AHD in asymptomatic overhead athletes. Forty-one volleyball athletes (24 men, 17 women; mean age: 16.1±1.5 years, body mass: 66.5±9.6 kg, body height: 179.6±8.4 cm, Body Mass Index: 20.5±2.3 kg/m2, time participating in overhead sports activity: 6.2±1.4 h/week, experience in sport: 4.1±2.4 years) were included in this study. Shoulder IR and ER ROM, total rotation ROM, AHD, shoulder isometric IR and ER strength and ER:IR strength ratio of the dominant side were tested before and after taping. Scapular taping increased the shoulder IR (PROM (PROM and ER:IR ratio did not change after taping (P=0.26, P=0.98, respectively). The results of this study suggest that scapular taping could be an effective method for enhancing the acromiohumeral distance, shoulder rotator strength and range of motion. Therefore, scapular taping could be recommended for not only in the asymptomatic athletes' shoulder exercise training but also in the prevention of subacromial impingement syndrome.
14. Dynamic ultrasound of the subacromial-subdeltoid bursa in patients with shoulder impingement: a comparison with normal volunteers.
Science.gov (United States)
Daghir, Ahmed A; Sookur, Paul A; Shah, Sachit; Watson, Martin
2012-09-01
The purpose of the study was to determine if the thickness of the subacromial-subdeltoid (SASD) bursa during dynamic ultrasound and on static views differs between patients with shoulder impingement syndrome and healthy volunteers. Twenty-two patients with a clinical diagnosis of shoulder impingement syndrome and 23 healthy volunteers were recruited. A subset of patients showing an immediate symptom response following intrabursal injection was identified as "injection responders". Ultrasound of the shoulder was performed on all participants using three standard static views and two dynamic views (before and after arm abduction). The thickness of both the intrabursal fluid and the superficial peribursal fat was measured on all views. The bursal thickness measurements in the two groups were compared using a t test for significance. The mean increase in SASD bursal fluid thickness following arm abduction was not statistically different among all patients (0.39 ± 0.41 mm) and controls (0.35 ± 0.32 mm), p = 0.72. The same was true comparing injection responders (0.46 ± 0.49 mm) with controls, p = 0.41. On static views, greater bursal fluid thickness was found in patients (1.01 ± 0.48 mm) compared with controls (0.67 ± 0.32 mm) when using the short axis view of the supraspinatus, p = 0.006. No statistically significant difference was found between injection responders and controls when measuring peribursal fat thickness on any view. Gathering of the SASD bursa demonstrated during dynamic ultrasound does not necessarily indicate painful impingement of the bursa as it is found to a similar degree in patients with a clinical diagnosis of impingement and healthy volunteers.
15. Exercises may be as efficient as subacromial decompression in patients with subacromial stage II impingement: 4-8-years' follow-up in a prospective, randomized study
DEFF Research Database (Denmark)
Haahr, J. P.; Andersen, JH
2006-01-01
not differ between treatment groups. Self-reported outcomes after 4-8 years did not differ between treatment groups. CONCLUSION: The results of surgical decompression were equal to those of conservative treatment, and the surgery group had more income transferrals during the first year of follow-up...... with graded physiotherapy and exercises or arthroscopic subacromial decompression. Outcomes were proportion of time per year with income transfers (indexed 0-1), including total transfers (marginalization), sick leave and disability pension obtained from the registry at the Ministry of Work. Self...
16. Efetividade da Terapia Manual na Síndrome de Conflito Subacromial
OpenAIRE
Silva, Sónia Isabel Oliveira da
2015-01-01
Introdução: A síndrome do conflito subacromial representa uma das causas mais comuns de dor no ombro. Neste tipo de conflito existe comprometimento do espaço subacromial, na maioria das vezes provocada pela compressão mecânica da coifa dos rotadores, especialmente da inserção do tendão do músculo supra-espinhoso, contra a superfície antero-inferior do acrómio. A etiologia desta condição tem sido debatida ao longo dos anos e muitos autores defendem que a sua causa é multi-fatorial. Estudos ass...
17. Distinguishing multiple rice body formation in chronic subacromial-subdeltoid bursitis from synovial chondromatosis.
Science.gov (United States)
Chen, Albert; Wong, Lun-Yick; Sheu, Chin-Yin; Chen, Be-Fong
2002-02-01
Multiple rice body formation is a complication of chronic bursitis. Although it resembles synovial chondromatosis clinically and on imaging, the literature suggests that analysis of radiographic and MR appearances should allow discrimination. We report the imaging findings in a 41-year-old man presenting with rice body formation in chronic subacromial-subdeltoid bursitis. We found that the signal intensity of the rice bodies is helpful in making the diagnosis.
18. Distinguishing multiple rice body formation in chronic subacromial-subdeltoid bursitis from synovial chondromatosis
Energy Technology Data Exchange (ETDEWEB)
Chen, Albert; Wong, Lun-Yick; Sheu, Chin-Yin [Department of Radiology, Mackay Memorial Hospital, Taipei (Taiwan); Chen, Be-Fong [Department of Pathology, Mackay Memorial Hospital, Taipei (Taiwan)
2002-02-01
Multiple rice body formation is a complication of chronic bursitis. Although it resembles synovial chondromatosis clinically and on imaging, the literature suggests that analysis of radiographic and MR appearances should allow discrimination. We report the imaging findings in a 41-year-old man presenting with rice body formation in chronic subacromial-subdeltoid bursitis. We found that the signal intensity of the rice bodies is helpful in making the diagnosis. (orig.)
19. Subdeltoid lipoma: a case with symptoms mimicking glenohumeral instability and subacromial impingement.
Science.gov (United States)
Ui, Michimasa; Ogawa, Kiyohisa
2010-06-09
Lipoma is the most frequently occurring benign soft tissue tumor in the shoulder and the axillary region in middle-aged and older persons, yet few such lipoma cases have been associated with clinical symptoms. A 38-year-old right-handed man presented with an enlarged feeling and a painful back-and-forth popping in his left shoulder. Although moderate tenderness of the subacromial bursa and bicipital groove existed, an obvious impingement sign was absent. Also not evidenced were signs of neurological deficits, limited range of motion, or any physical findings suggestive of instability. Magnetic resonance imaging showed a homogenous tumor in the subdeltoid that was isointense relative to the subcutaneous fat and fluid collection in the hypertrophic subacromial bursa. As the tumor was considered from the clinical and imaging findings to be attributable to all clinical symptoms, it was resected en bloc with a satisfactory result. Histopathologically, the tumor showed typical features of a simple lipoma. To our knowledge, the present case is the first of a subdeltoid intermuscular lipoma of which mechanism developing symptoms was preoperatively surmised from imaging. The symptom-mimicking shoulder instability was assumed to be produced by the back-and-forth snapping of the lipoma beneath the deltoid muscle. The mechanism for developing the subacromial impingement-like symptom was surmised to derive from the middle deltoid fibers pressuring the lipoma to push up into the subacromial space. This case is presented to emphasize the careful reading of imaging in considering the pathomechanism of the attributing symptoms. Copyright 2010, SLACK Incorporated.
20. Diagnosis of shoulder impingement syndrome; Diagnostik des Schulterimpingementsyndroms
Energy Technology Data Exchange (ETDEWEB)
Hodler, J. [Orthopaedische Universitaetsklinik Balgrist, Zuerich (Switzerland)
1996-12-01
This article reviews the pathogenesis and clinical and imaging findings in shoulder impingement syndrome. Different stages of impingement syndrome are described. Stage I relates to edema and hemorrhage of the supraspinatus tendon. Stage II is characterized by bursal inflammation and fibrosis, as well as tendinopathy. In stage III there is a tear of the rotator cuff. Clinical signs many overlap. Moreover, calcifying tendinitis, fractures and pain originating from the cervical spine may mimic shoulder impingement syndrome. Imaging is important for the exact diagnosis. Standard radiographs are the basis of imaging in shoulder impingement syndrome. They may demonstrate subchondral sclerosis of the major tuberosity, subacromial spurs, and form anomalies of the acromion. They are also important in the differential diagnosis of shoulder impingement syndrome and demonstrate calcifying tendinitis, fractures and neoplasm. Ultrasonography has found acceptance as a screening tool and even as a final diagnostic method by many authors. However, there is a high interobserver variability in the demonstration of rotator cuff tears. Its usefulness has therefore been questioned. MR imaging is probably the method of choice in the evaluation of the rotator cuff and surrounding structures. Several investigations have demonstrated that differentiation of early findings, such as tendinopathy versus partial tears, may be difficult with MR imaging. However, reproducibility for fullthickness tears appears to be higher than for sonography. Moreover, specificity appears to be superior to sonography. MR arthrography is not universally accepted. However, it allows for more exact differentiation of discrete findings and may be indicated in preoperative planning. Standard arthrography and CT have a limited role in the current assessment of the rotator cuff. (orig.) [Deutsch] Grundlage des Impingementsyndroms ist eine Kompression des Supraspinatus am akromioklavikularen Bogen vor allem bei Flexion
1. Efficacy and safety of rotating pigtail catheter: lower extremity deep vein thrombosis of may-thurner syndrome
Energy Technology Data Exchange (ETDEWEB)
Kim, Yoon Kyung; Kang, Byung Chul [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of); Gang, Sung Gown [College of Medicine, Ewha Womans Univ., Seoul (Korea, Republic of)
2004-07-01
The purpose of this study was to evaluate the efficacy and safety of mechanical fragmentation of iliofemoral deep vein thromboses (DVTs) with a rotating pigtail catheter followed by aspiration thrombectomy. Ten patients (eight females, two males, 56.8 +/- 21.37 years) with iliofemoral DVT underwent treatment for a total of ten affected limbs. Approximately 5-10 min after infusing 400,000-700,000 IU urokinase (UK) into the thrombosed deep veins, the thromboses were fragmented by the mechanical action of the rotating pigtail catheter tip. Following their fragmentation, the fragmented thromboses were aspirated. After completion of the above procedure, a stent was inserted if iliac vein stenosis was demonstrated. We evaluated the total procedure time, volume of thrombolytic agent (urokinase), valvular injury, symptom-free time interval and success rate (primary patency rate). In all 10 patients, the iliofemoral deep vein thrombosis was successfully fragmented and aspirated using the combination method of a rotating pigtail catheter and aspiration thrombectomy (clinical and technical success rate, 100%). The thromboses were declotted by means of a rotating pigtail catheter with an average treatment time of 5.7 minutes. The average duration of the total intervention was 108 min. The mean primary patency was approximately 4 months with no recurrence. The total UK dose was 890,000 IU on average. There were no major complications, such as pulmonary embolism or cerebral hemorrhage, while performing the thrombus-fragmentation procedure using the rotating pigtail catheter. The combination method of a rotating pigtail catheter and aspiration thrombectomy for the treatment of iliofemoral deep vein thrombosis was found to be rapid, safe and effective for accomplishing recanalization in all cases without complication. Therefore, this procedure constitutes a potential treatment option in patients presenting with iliofemoral vein thrombosis.
2. Shoulder Joint and Muscle Characteristics Among Weight-Training Participants With and Without Impingement Syndrome.
Science.gov (United States)
Kolber, Morey J; Hanney, William J; Cheatham, Scott W; Salamh, Paul A; Masaracchio, Michael; Liu, Xinliang
2017-04-01
Kolber, MJ, Hanney, WJ, Cheatham, SW, Salamh, PA, Masaracchio, M, and Liu, X. Shoulder joint and muscle characteristics among weight-training participants with and without impingement syndrome. J Strength Cond Res 31(4): 1024-1032, 2017-Subacromial impingement syndrome (SIS) has been reported as an etiological source of shoulder pain among weight-training (WT) participants; however, a paucity of evidence exists to describe intrinsic risk factors. The purpose of this study was to investigate specific risk-related joint and muscle adaptations among WT participants identified as having SIS based on a previously validated clinical testing cluster. Fifty-five men (mean age 27.3 years) who participated in recreational WT a minimum of 2 d·wk were recruited, including 24 individuals with SIS and 31 without SIS serving as controls. Active range of motion (AROM), bodyweight-adjusted strength values, and strength ratios were compared between groups. Significant differences were present as WT participants with SIS had decreased internal and external rotation AROM (p ≤ 0.016) and decreased bodyweight-adjusted strength values of the external rotator and lower trapezius musculature (p ≤ 0.02) when compared with WT participants without SIS. Select strength ratios were greater in the SIS group (p ≤ 0.004) implying agonist to antagonist muscle imbalances. The impaired joint and muscle characteristics identified among WT participants with SIS are not without consequence, as they are associated with shoulder disorders in both general and athletic populations. Practical applications for these findings may reside in exercise prescription that addresses internal rotation mobility, mitigates training bias, and favors muscles responsible for stabilization, such as the external rotators and lower trapezius. Strength and conditioning professionals should consider risk-related adaptations associated with WT when prescribing upper-extremity exercises.
3. Static and Dynamic Shoulder Imaging to Predict Initial Effectiveness and Recurrence After Ultrasound-Guided Subacromial Corticosteroid Injections.
Science.gov (United States)
Chang, Ke-Vin; Wu, Wei-Ting; Han, Der-Sheng; Özçakar, Levent
2017-10-01
4. Thoracic Outlet Syndrome
Science.gov (United States)
... TOS, including rotator cuff injuries, cervical disc disorders, fibromyalgia, multiple sclerosis, complex regional pain syndrome, and tumors ... TOS, including rotator cuff injuries, cervical disc disorders, fibromyalgia, multiple sclerosis, complex regional pain syndrome, and tumors ...
5. Effectiveness of physical therapy treatment of clearly defined subacromial pain: a systematic review of randomised controlled trials.
Science.gov (United States)
Haik, M N; Alburquerque-Sendín, F; Moreira, R F C; Pires, E D; Camargo, P R
2016-09-01
To summarise the current evidence regarding the effectiveness of physical therapy on pain, function and range of motion in individuals with subacromial pain syndrome (SAPS). Systematic review. PubMed, Web of Science, CINAHL, Cochrane, Embase, Lilacs, Ibecs and Scielo databases. Randomised controlled trials (RCTs) investigating physical therapy modalities for SAPS on pain, function/disability or range of motion were included. 64 high-quality RCTs were included. Exercise therapy provided high evidence of being as effective as surgery intervention and better than no treatment or placebo treatment to improve pain, function and range of motion in the short, mid and long terms. The combination of mobilisation and exercises provided high evidence to decrease pain and improve function in the short term. There is limited evidence for improvements on the outcomes with the isolated application of manual therapy. High level of evidence was synthesised regarding the lack of beneficial effects of physical resources such as low-level laser, ultrasound and pulsed electromagnetic field (PEMF) on pain, function or range of motion in the treatment of SAPS. There is limited evidence for microwave diathermy and transcutaneous electrical nerve stimulation. There is moderate evidence to no benefits with taping in the short term. Effects of diacutaneous fibrolysis and acupuncture are not well established yet. Exercise therapy should be the first-line treatment to improve pain, function and range of motion. The addition of mobilisations to exercises may accelerate reduction of pain in the short term. Low-level laser therapy, PEMF and taping should not be recommended. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
6. Treatment of axillary web syndrome using instrument assisted soft tissue mobilization and thoracic manipulation for associated thoracic rotation dysfunction: A case report.
Science.gov (United States)
Crane, Patricia; Ladden, Jaclyn; Monica, Danielle
2017-08-30
There is a paucity of research that investigates physical therapy management for patients with axillary web syndrome (AWS) and thoracic rotation dysfunction. The purpose of this case report is to describe the management of a patient with AWS and thoracic rotation dysfunction using an impairment-based approach that includes instrument assisted soft tissue mobilization (IASTM), thoracic manipulation, and stretching. The patient was a 48-year-old female with a past medical history of bilateral breast cancer with a bilateral latissimus dorsi flap reconstruction. The patient was referred to physical therapy with chief complaints of right shoulder pain with reaching and an inability to resume running due to right shoulder and scapula pain. The patient was seen in outpatient physical therapy for four visits over four weeks. Treatment consisted of IASTM, thoracic manipulation, stretching exercises, and home exercise program instruction. Upon discharge, the patient had improved right shoulder and thoracic range of motion, decreased pain, and improved function on the patient specific functional scale (PSFS). Utilization of an impairment-based physical therapy approach to treat a patient with AWS and thoracic dysfunction yielded positive outcomes. Further research on the efficacy of IASTM and physical therapy management of AWS is warranted.
7. Gene-gene interaction between serotonin transporter (SLC6A4) and CLOCK modulates the risk of metabolic syndrome in rotating shiftworkers.
Science.gov (United States)
Sookoian, Silvia; Gianotti, Tomas Fernandez; Burgueño, Adriana; Pirola, Carlos Jose
2010-07-01
Serotonergic neurotransmission and the master circadian CLOCK gene are physiological modulators of the circadian system. In addition, both are involved in the physiopathology of metabolic syndrome (MS). The authors sought to examine the potential effect of the gene-gene interaction between the functional 44-bp insertion/deletion polymorphism in the promoter region (serotonin-transporter-linked promoter region polymorphism or 5-HTTLPR) of the serotonin transporter gene (SLC6A4) and common variants of the gene CLOCK on the genetic risk underlying MS of shift-workers. To test this hypothesis, 856 men were studied; 518 dayworkers were compared with 338 rotating shiftworkers. Medical history, health examination including anthropometric and arterial blood pressure measurements, a questionnaire on health-related behaviors, and biochemical determinations were obtained from every participant. 5-HTTLPR genotypes were determined using polymerase chain reaction followed by gel electrophoresis. Six tag single-nucleotide polymorphisms (SNPs) in the CLOCK gene with a minor allele frequency >10 % (rs1554483 C/G, rs11932595 A/G, rs4580704 C/G, rs6843722 A/C, rs6850524 C/G, and rs4864548 A/G), encompassing 117 kb of chromosome 4 and representing 115 polymorphic sites (r(2) > .8), were genotyped. A significant interaction between the 5-HTTLPR variant and the haplotype rs1554483-rs4864548 of the CLOCK gene was detected for diastolic (p = .0058) and systolic blood pressure (p = .0014), arterial hypertension (p = .033), plasma triglycerides levels (p = .033), and number of MS components (p = .01). In all these cases, the higher values were observed in rotating shiftworkers homozygous for the SLC6A4 S allele and carrying the haplotype composed by the CLOCK rs1554483 G and rs4864548 A variants. In conclusion, these data suggest a potential interaction (epistatic effect) of serotonin transporter and CLOCK gene variation on the genetic susceptibility to develop MS by rotating shiftworkers.
8. Fisioterapia en el síndrome subacromial del hombro. Revisión sistemática cualitativa.
OpenAIRE
Zhou, Yanxiang
2014-01-01
Trabajo Fin de Grado (TFG) Antecedentes: El dolor de hombro es un problema muy frecuente, se estima que un tercio de la población sufre o sufrirá a lo largo de la vida dolor de hombro en alguna ocasión. El síndrome subacromial es la causa más común. La fisioterapia es la terapia de elección frente al síndrome subacromial, con una gran variedad abordajes fisioterapéuticos como los ejercicios terapéuticos, la terapia manual, el ultrasonido, la acupuntura, etc. Objetivo: El objetivo de est...
9. Regenerative Medicine in Rotator Cuff Injuries
Directory of Open Access Journals (Sweden)
Pietro Randelli
2014-01-01
Full Text Available Rotator cuff injuries are a common source of shoulder pathology and result in an important decrease in quality of patient life. Given the frequency of these injuries, as well as the relatively poor result of surgical intervention, it is not surprising that new and innovative strategies like tissue engineering have become more appealing. Tissue-engineering strategies involve the use of cells and/or bioactive factors to promote tendon regeneration via natural processes. The ability of numerous growth factors to affect tendon healing has been extensively analyzed in vitro and in animal models, showing promising results. Platelet-rich plasma (PRP is a whole blood fraction which contains several growth factors. Controlled clinical studies using different autologous PRP formulations have provided controversial results. However, favourable structural healing rates have been observed for surgical repair of small and medium rotator cuff tears. Cell-based approaches have also been suggested to enhance tendon healing. Bone marrow is a well known source of mesenchymal stem cells (MSCs. Recently, ex vivo human studies have isolated and cultured distinct populations of MSCs from rotator cuff tendons, long head of the biceps tendon, subacromial bursa, and glenohumeral synovia. Stem cells therapies represent a novel frontier in the management of rotator cuff disease that required further basic and clinical research.
10. Two Cases of Subacromial Bursitis with Many Loose Bodies as a Cause of Rheumatoid Arthritis
OpenAIRE
砂川, 融; 杉村, 功; 堀, 司郎; 村岡, 博; 有田, 淳
1989-01-01
Rice bodies caused by T.B. and R.A. in joints are relatively common and reported, but in bursa are rare. We experienced two cases of subacromial bursitis with many rice bodies :one is a 53-year-old female and the other is a 62-year-old male. They were suffering from rheumatoid arthritis for years, and complained of swelling of the shoulder joint, but had no pain and no remarkable limitation of range of motion of the shoulder joint. We resected the bursa containing a lot of rice bodies operati...
11. Home exercises and supervised exercises are similarly effective for people with subacromial impingement: a randomised trial
Directory of Open Access Journals (Sweden)
Fredrik Granviken
2015-07-01
Full Text Available Question: Are there different effects of home exercises and supervised exercises on pain and disability for people with subacromial impingement? Design: Randomised trial with two treatment arms, concealed allocation, blinded assessment of some outcomes, and intention-to-treat analysis. Participants: Forty-six patients with subacromial impingement were recruited from an interdisciplinary outpatient clinic of physical medicine and rehabilitation at a university hospital in Norway. Intervention: The home exercise group had one supervised exercise treatment followed by exercises at home for 6 weeks. The supervised exercise group had up to 10 supervised exercise treatments in addition to home exercises for 6 weeks. Outcome measures: The primary outcome was the Shoulder Pain and Disability Index (SPADI. Secondary outcome variables were: average pain during the past week, the Fear Avoidance Beliefs Questionnaire, participant satisfaction with treatment, active range of motion, work status and clinical shoulder tests. Pain was assessed weekly and all outcomes were assessed at 6 weeks. Participants were free to seek ongoing treatment of their choice until 26 weeks, when the SPADI was assessed again. Results: While both groups improved considerably, the groups did not differ significantly on the SPADI after the intervention at 6 weeks (0 points, 95% CI –14 to 14 or when followed up at 26 weeks (–2 points, 95% CI –21 to 17. There were no between-group differences for pain at any time. The remaining outcomes also did not differ significantly, except for the clinical tests of shoulder impingement. In the supervised exercise group, 11 out of 23 participants had two or more positive tests, compared to 18 out of 21 in the home exercise group. Conclusion: Supervision of more than the first session of a 6-week exercise regimen did not cause significant differences in pain and disability in people with subacromial impingement. Trial registration: NCT01257113
12. Efectos del uso de acupuntura en el síndrome subacromial
OpenAIRE
Rueda Garrido, Juan Carlos
2014-01-01
Antecedentes: El hombro doloroso u omalgia, es una de las principales causas de dolor osteoarticular que se presentan en la práctica clínica diaria, y a menudo provoca discapacidad funcional considerable. La causa más frecuente de dolor de hombro es el síndrome subacromial. Objetivo: Conseguir una disminución de la intensidad del dolor a corto y medio plazo con el uso de acupuntura en el hombro lesionado. Método: Estudio controlado y aleatorizado, en el que participan dos grupos: uno qu...
13. Is radial Extracorporeal Shock Wave Therapy (rEWST) combined with supervised exercises (SE) more effective than sham rESWT and SE in patients with subacromial shoulder pain? Study protocol for a double-blind randomised, sham-controlled trial.
Science.gov (United States)
Kvalvaag, Elisabeth; Brox, Jens Ivar; Engebretsen, Kaia Beck; Søberg, Helene Lundgaard; Bautz-Holter, Erik; Røe, Cecilie
2015-09-11
Subacromial shoulder pain is a common complaint. Radial Extracorporeal Shock Wave Therapy (rESWT) has being increasingly used to treat calcific and non-calcific tendinosis, although there is no evidence of the effectiveness of rESWT in non-calcific tendinosis of the rotator cuff. A randomised single blind study showed that the short-term effect of supervised exercises (SE) was significantly better than rESWT on subacromial shoulder pain, but both groups improved. In a clinical trial on achilles tendinopathy rESWT improved the effectiveness of treatment with eccentric loading. The objective of this present study is to evaluate if rESWT in addition to SE is more effective in improving shoulder pain and function compared with sham rESWT and SE in patients with subacromial shoulder pain. This is a double blind, randomised sham-controlled trial which is performed at the shoulder clinic at the Department of Physical Medicine and Rehabilitation in Oslo University Hospital, Norway. One-hundred-forty-four patients with subacromial shoulder pain lasting at least 3 months, age from 25 to 70 years old are included in the trial. Patients are randomly allocated in 1:1 ratio to receive either rESWT or sham rESWT once a week in addition to SE once a week for the initial 4 weeks. Subsequently SE are provided twice a week for 8 weeks. The primary outcome measure is a change in the Shoulder Pain and Disability Index (SPADI) at 24 weeks follow-up. Secondary outcomes include return to work, pain at rest and on activity, function, and health related quality of life. The patients, the physiotherapist providing the exercise regimen and the outcome assessor are blinded to group assignment. The physiotherapist providing the rESWT is not blinded. Because of the extensive use of rESWT in the treatment of subacromial shoulder pain the results of this trial will be of importance and have impact on clinical practice. ClinicalTrials.gov NCT01441830.
14. Electromyographic analysis of the rotator cuff in postoperative shoulder patients during passive rehabilitation exercises.
Science.gov (United States)
Murphy, Cynthia A; McDermott, William J; Petersen, Roger K; Johnson, Scott E; Baxter, Stephanie A
2013-01-01
15. Rotator Cuff Injuries.
Science.gov (United States)
Connors, G. Patrick
Many baseball players suffer from shoulder injuries related to the rotator cuff muscles. These injuries may be classified as muscular strain, tendonitis or tenosynovitis, and impingement syndrome. Treatment varies from simple rest to surgery, so it is important to be seen by a physician as soon as possible. In order to prevent these injuries, the…
16. Evaluation of the Trends, Concomitant Procedures, and Complications With Open and Arthroscopic Rotator Cuff Repairs in the Medicare Population.
Science.gov (United States)
Jensen, Andrew R; Cha, Peter S; Devana, Sai K; Ishmael, Chad; Di Pauli von Treuheim, Theo; D'Oro, Anthony; Wang, Jeffrey C; McAllister, David R; Petrigliano, Frank A
2017-10-01
Medicare insures the largest population of patients at risk for rotator cuff tears in the United States. To evaluate the trends in incidence, concomitant procedures, and complications with open and arthroscopic rotator cuff repairs in Medicare patients. Cohort study; Level of evidence, 3. All Medicare patients who had undergone open or arthroscopic rotator cuff repair from 2005 through 2011 were identified with a claims database. Annual incidence, concomitant procedures, and postoperative complications were compared between these 2 groups. In total, 372,109 rotator cuff repairs were analyzed. The incidence of open repairs decreased (from 6.0 to 4.3 per 10,000 patients, P arthroscopic repairs increased (from 4.5 to 7.8 per 10,000 patients, P arthroscopic group were more likely to have undergone concomitant subacromial decompression than those in the open group (87% vs 35%, P arthroscopic, P arthroscopic rotator cuff repairs have increased in incidence and now represent the majority of rotator cuff repair surgery. Among concomitant procedures, subacromial decompression was most commonly performed despite evidence suggesting a lack of efficacy. Infections and stiffness were rare complications that were slightly but significantly more frequent in open rotator cuff repairs.
17. Shoulder impingement syndrome : evaluation of the causes with MRI
Energy Technology Data Exchange (ETDEWEB)
Choi, Yong Ho; Song, In Sup; Chung, Hun Young; Yoon, Sang Jin; Kim, Yang Soo; Shim, Hyung Jin; Choi, Young Hee; Lee, Jong Beum; Lee, Yong Chul; Kim, Kun Sang [Chungang Univ. College of Medicine, Seoul (Korea, Republic of); Choi, Yun Sun [Eulji Hospital, College of Medicine, Seoul (Korea, Republic of)
1999-12-01
Various mechanical causes which induce shoulder impingement syndrome have been identified with the help of MRI. The aim of this study is to evaluate the incidence of such causes. A total of 54 patients with clinically confirmed shoulder impingement syndrome and a normal control group(n=20) without symptoms were included. We evaluated the incidence of hook shaped acromion, low lying acromion, downward slope of the acromion, subacromial spur, acromioclavicular joint hypertrophy, coracoacromial ligament hypertrophy, high cuff muscle bulk, and os acromiale. Among the 54 patients, the following conditions were present: acromioclavicular joint hypertrophy(n=36), coracoacromial ligament hypertrophy(n=20), subacromial spur(n=18), downward sloping of the acromion(n=16), hook shaped acromion(n=11), relatively high cuff muscle bulk(n=6), low lying acromion relative to the clavicle(n=3), and os acromiale(n=1). In the normal control group there were nine cases of acromioclavicular joint hypertrophy, nine of coracoacromial ligament hypertrophy, nine of downward sloping acromion, and three of low lying acromion, but hook shaped acromion, high cuff muscle bulk, and os acromiale were not found. Among 54 patients, the syndrome was due to five simultancous causes in one patient, four causes in two, three causes in 12, two causes in 22, and one cause in 17. Hook shaped acromion and subacromial spur are the statistically significant causes of shoulder impingement syndrome. In 69% of patients, the condition was due to more than one cause.
18. [Isolated synovial chondromatosis of the subacromial bursa: report of a new case and review of the literature].
Science.gov (United States)
Bouhaouala, M H; Saïd, W; Salah, M Haj; Bouaziz, N; Mourali, S; Chaabane, S
2006-01-01
Synovial chondromatosis is a rare metaplasia of the synovium of unknown etiology that may involve occasionally the subacromial bursa. We report a new case diagnosed by ultrasound in a 30-year-old man and we present pathogenetic, diagnostic and therapeutic features of this disease with a literature review.
19. Accuracy of diagnostic ultrasound in patients with suspected subacromial disorders: a systematic review and meta-analysis.
NARCIS (Netherlands)
Ottenheijm, R.P.; Jansen, M.J.; Staal, J.B.; Bruel, A. van den; Weijers, R.E.; Bie, R.A. de; Dinant, G.J.
2010-01-01
OBJECTIVE: To determine the diagnostic accuracy of ultrasound for detecting subacromial disorders in patients presenting in primary and secondary care settings. DATA SOURCES: Medline and Embase were searched on June 9, 2010. In addition, the reference list of 1 systematic review and all included
20. Rotational seismology
Science.gov (United States)
Lee, William H K.
2016-01-01
Rotational seismology is an emerging study of all aspects of rotational motions induced by earthquakes, explosions, and ambient vibrations. It is of interest to several disciplines, including seismology, earthquake engineering, geodesy, and earth-based detection of Einstein’s gravitation waves.Rotational effects of seismic waves, together with rotations caused by soil–structure interaction, have been observed for centuries (e.g., rotated chimneys, monuments, and tombstones). Figure 1a shows the rotated monument to George Inglis observed after the 1897 Great Shillong earthquake. This monument had the form of an obelisk rising over 19 metres high from a 4 metre base. During the earthquake, the top part broke off and the remnant of some 6 metres rotated about 15° relative to the base. The study of rotational seismology began only recently when sensitive rotational sensors became available due to advances in aeronautical and astronomical instrumentations.
1. Long-Term MRI Findings in Operated Rotator Cuff Tear
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Kyroelae, K.; Niemitukia, L.; Jaroma, H.; Vaeaetaeinen, U. [Kuopio Univ. Hospital (Finland). Dept. of Orthopaedics and Traumatology
2004-08-01
Purpose: To describe magnetic resonance imaging (MRI) findings at long-term follow-up after rotator cuff (RC) tear using standard MRI sequences without fat saturation. Material and Methods: Twenty-eight patients aged 55.8{+-}7.6 underwent MRI examination 4.6{+-}2.1 years after surgery for RC tear. Standard sequences in oblique coronal, oblique sagittal, and axial planes were obtained. The RC, including re-tears and tendon degeneration, was independently evaluated by two observers. Thickness of the supraspinatus tendon and narrowing of the subacromial space were measured. The clinical outcome was evaluated with the Constant score and compared with the MRI findings. Results: The RC tear was traumatic in 18 (64%) patients and degenerative in 10 (36%). At follow-up, 11 (39%) had normal RC tendons with good clinical outcome. Four (14%) patients had painful tendinosis without RC tear. A full-thickness RC tear was found in 7 (25%) patients and a partial tear in 6 (21%). In one patient with a full-thickness tear, and in two with partial tear, tendinosis was found in another of the RC tendons. The subacromial space was narrowed in 13 (46%) of the patients. A narrowing of the subacromial space correlated with re-tear (P<0.05). Conclusions: The RC may be evaluated with standard MRI sequences without fat saturation at long-term follow-up. A normal appearance of the RC is correlated with good clinical outcome, while re-tear and tendinosis are associated with pain.
2. Shoulder kinematic features using arm elevation and rotation tests for classifying patients with frozen shoulder syndrome who respond to physical therapy.
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Yang, Jing-lan; Chang, Chein-wei; Chen, Shiau-yee; Lin, Jiu-jenq
2008-12-01
Physical therapy is an intervention commonly used in the treatment of subjects with frozen shoulder symptoms, with limited proven effect. The purpose of this study was to identify the kinematic features of patients with frozen shoulder who are more likely to respond to physical therapy. Thirty-four subjects presenting frozen shoulder syndrome were studied to determine altered shoulder kinematics and functional disability. Subjects received the same standardized treatment with passive mobilization/stretching techniques, physical modalities (i.e. ultrasound, shortwave diathermy and/or electrotherapy) and active exercises twice a week for 3 months. Initially, subjects were asked to perform full active motion in 3 tests: abduction in the scapular plane, hand-to-neck and hand-to-scapula. During the test, shoulder kinematics were measured using a 3-D electromagnetic motion-capturing system. In the initial and follow-up sessions, the self-reported Flexilevel Scale of Shoulder Function (FLEX-SF) was used to determine functional disability from symptoms. Improvement with treatment was determined using percent change in FLEX-SF scores over three months of treatment [(final score-initial score)/initial score x 100, >20% improvement and 8.4 degrees during arm elevation, and external rotation >38.9 degrees during hand to neck) were identified. The presence of these two variables (positive likelihood ratio=15.71) increased the probability of improvement with treatment from 41% to 92%. It appears that shoulder kinematics may predict improvement in subjects with frozen shoulder syndrome. Prospective validation of the proposed prediction method is warranted.
3. Radiological evaluation of acromial characteristic using supraspinatus outlet view in shoulder impingement syndrome
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Marcel Prasetyo
2007-09-01
Full Text Available Purpose of this study was to find the association between shoulder impingement syndrome (SIS and morphological characteristics of acromion (acromial tilt angle, type of acromion, subacromial osteophyte. Supraspinatus outlet view was performed using fluoroscopy. There were 40 SIS patients and 40 individuals with no shoulder pain examined and measured for their acromial tilt angle, type of acromion (according to Bigliani’s classification and Park’s criteria and for the presence of subacromial osteophyte. Average acromial tilt angle was 34.1° (SD 7.6 for SIS group and 32.1° (SD 7.7 for control group. Type II acromion was found more frequent in both groups (85% and 95%. The association between SIS and acromial tilt angle or between SIS and type of acromion were statistically insignificant (p=0.241 and p=0.221. Subacromial osteophyte was found in 52.5% of SIS group compare to 12.5% among the control group, and the association with SIS was statistically significant (p=0.0003. Subacromial osteophyte was found to have significant association with SIS. Such association was not found in acromial tilt angle and type of acromion. (Med J Indones 2007; 16:176-80 Keywords: shoulder impingement syndrome, acromion, supraspinatus
4. Intense focused ultrasound stimulation of the rotator cuff: evaluation of the source of pain in rotator cuff tears and tendinopathy.
Science.gov (United States)
Gellhorn, Alfred C; Gillenwater, Cody; Mourad, Pierre D
2015-09-01
The objective of this preliminary study was to evaluate the ability of individual 0.1-s long pulses of intense focused ultrasound (iFU) emitted with a carrier frequency of 2 MHz to evoke diagnostic sensations when applied to patients whose shoulders have rotator cuff tears or tendinopathy. Patients were adults with painful shoulders and clinical and imaging findings consistent with rotator cuff disease. iFU stimulation of the shoulder was performed using B-mode ultrasound coupled with a focused ultrasound transducer that allowed image-guided delivery of precisely localized pulses of energy to different anatomic areas around the rotator cuff. The main outcome measure was iFU spatial average-temporal average intensity (I_SATA), and location required to elicit sensation. In control patients, iFU produced no sensation throughout the range of stimulation intensities (≤2000 W/cm(2) I_SATA). In patients with rotator cuff disease, iFU was able to induce sensation in the tendons of the rotator cuff, the subacromial bursa, and the subchondral bone in patients with chronic shoulder pain and rotator cuff disease, with an average ± standard deviation intensity equaling 680 ± 281 W/cm(2) I_SATA. This result suggests a primary role for these tissues in the pathogenesis of shoulder pain related to rotator cuff tendinopathy. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
5. Effect of methylprednisolone use on the rotator cuff in rats: biomechanical and histological study
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Gustavo Vinícius Ghellioni
2015-06-01
Full Text Available OBJECTIVE: To evaluate the influence of treatment with different doses of methylprednisolone on the mechanical resistance and possible histological alterations of the rotator cuff tendon in rats.METHODS: Male Wistar rats were divided randomly into four treatment groups: sham, vehicle or 0.6 mg/kg or 6.0 mg/kg of methylprednisolone. Changes to mechanical resistance (in N and histological parameters (fibrillar appearance, presence of collagen, edema and vascular proliferation of the rotator cuff tendon were evaluated. The analyses were conducted after administration of one treatment (24 h afterwards, two treatments (7 days afterward or three treatments (14 days afterwards, into the subacromial space.RESULTS: Seven and fourteen days after the treatments were started, it was found that in a dose-dependent manner, methylprednisolone reduced the mechanical resistance of the rotator cuff tendon (p < 0.05 in relation to the vehicle group. Modifications to the histological parameters were observed on the 7th and 14th days after the first infiltration, especially regarding the presence of collagen and vascular proliferation, for the dose of 0.6 mg/kg of methylprednisolone, and also regarding the presence of collagen, edema and vascular proliferation for the dose of 6.0 mg/kg of corticoid.CONCLUSION: The results obtained demonstrated a relationship between methylprednisolone use through infiltration into the subacromial space and reduction of the mechanical resistance of and histological modifications to the rotator cuff tendon in rats.
6. Utilizing the metabolic syndrome component count in workers' health surveillance: An example of day-time vs. day-night rotating shift workers.
Science.gov (United States)
Lin, Yu Cheng; Hsieh, I-Chun; Chen, Pau-Chung
2015-01-01
To establish a practical method for assessing the general metabolic health conditions among different employee groups, this study utilized the total count of metabolic syndrome (MetS) elements as a parameter, and performed a retrospective analysis comparing changes of MetS component count (MSC) of 5 years among day-time work (DW) and day-andnight rotating shift work (RSW) employees. The data of personal histories, physical examinations, blood tests, abdominal sonographic examinations and occupational records were collected from a cohort of workers in an electronics manufacturing company. We first defined the arithmetic mean value of MSC as MSC density (MSCD) for the employee group; then we compared the changes of MSCD over 5 years between DW and RSW workers. Occupational, personal and health records were analyzed for the 1077 workers with an initial mean age of 32.4 years (standard deviation (SD): 6.2 years), including 565 RSW workers (52%). The initial MSCDs were 1.26 and 1.12 (p = 0.06) for DW and RSW workers, respectively; after 5 years, the increments of MSCD for DW and RSW workers were 0.10 and 0.39, respectively (p employee group; MSC, MSCD and their transitional changes can be applied as simple and standardized tools for monitoring metabolic health risk profiles when managing employee health, at both the individual and company levels. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.
7. Efeito da rotação do quadril na síndrome da dor femoropatelar Effect of hip rotation on patellofemoral pain syndrome
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K Gramani-Say
2006-01-01
8. Conservative treatment for patients with subacromial impingement: Changes in clinical core outcomes and their relation to specific rehabilitation parameters
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Mikkel B. Clausen
2018-02-01
Full Text Available Background Impaired patient-reported shoulder function and pain, external-rotation strength, abduction strength, and abduction range-of-motion (ROM is reported in patients with subacromial impingement (SIS. However, it is unknown how much strength and ROM improves in real-life practice settings with current care. Furthermore, outcomes of treatment might depend on specific rehabilitation parameters, such as the time spent on exercises (exercise-time, number of physiotherapy sessions (physio-sessions and number of corticosteroid injections, respectively. However, this has not previously been investigated. The purpose of this study was to describe changes in shoulder strength, ROM, patient-reported function and pain, in real-life practice settings, and explore the association between changes in clinical core outcomes and specific rehabilitation parameters. Methods Patients diagnosed with SIS at initial assessment at an outpatient hospital clinic using predefined criteria’s, who had not undergone surgery after 6 months, were included in this prospective cohort study. After initial assessment (baseline, all patients underwent treatment as usual, with no interference from the investigators. The outcomes Shoulder Pain and Disability Index (SPADI:0–100, average pain (NRS:0–10, external rotation strength, abduction strength and abduction ROM, pain during each test (NRS:0–10, were collected at baseline and at six month follow-up. Amount of exercise-time, physio-sessions and steroid-injections was recorded at follow-up. Changes in outcomes were analyzed using Wilcoxon Signed-Rank test, and the corresponding effect sizes (ES were estimated. The associations between changes in outcomes and rehabilitation parameters were explored using multiple regression analyses. Results Sixty-three patients completed both baseline and follow-up testing. Significant improvements were seen in SPADI (19 points, ES:0.53, p 0.2. A higher number of physio-sessions was
9. Long-Term Results of the Diagnostic Tests for Subacromial Impingement Syndrome
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Bayram Kelle
2015-12-01
Results: There were no significant differences for demographic data between groups. The all tests in both group were found mostly positive. It was seen significant change at the third months after treatment. Conclusions: The specific tests were important fort he diagnosis of SIS, furthermore they can demonstrate the efficacy of treatments. The combinad application of these tests are more important for the diagnosis and follow-up of SIS. [Cukurova Med J 2015; 40(4.000: 794-799
10. The Painful Shoulder: Shoulder Impingement Syndrome
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Khan, Yousaf; Nagy, Mathias Thomas; Malal, Joby; Waseem, Mohammad
2013-01-01
Rotator cuff disorders are considered to be among the most common causes of shoulder pain and disability encountered in both primary and secondary care. The general pathology of subacromial impingment generally relates to a chronic repetitive process in which the conjoint tendon of the rotator cuff undergoes repetitive compression and micro trauma as it passes under the coracoacromial arch. However acute traumatic injuries may also lead to this condition. Diagnosis remains a clinical one, however advances in imaging modalities have enabled clinicians to have an increased understanding of the pathological process. Ultrasound scanning appears to be a justifiable and cost effective assessment tool following plain radiographs in the assessment of shoulder impingment, with MRI scans being reserved for more complex cases. A period of observed conservative management including the use of NSAIDs, physiotherapy with or without the use of subacromial steroid injections is a well-established and accepted practice. However, in young patients or following any traumatic injury to the rotator cuff, surgery should be considered early. If surgery is to be performed this should be done arthroscopically and in the case of complete rotator cuff rupture the tendon should be repaired where possible. PMID:24082973
11. Arthroscopic treatment of a case with concomitant subacromial and subdeltoid synovial chondromatosis and labrum tear.
Science.gov (United States)
Aydogan, Nevres Hurriyet; Kocadal, Onur; Ozmeric, Ahmet; Aktekin, Cem Nuri
2013-01-01
Synovial chondromatosis is a disease that seldomly seen in shoulder joint and is related to benign synovial proliferation and synchronous chondral tissue formation within the joint cavity. Patients suffer from progressive restriction of range of motion and shoulder pain. Extra-articular involvement is an extremely rare condition. Degenerative osteoarthritis, joint subluxation, and bursitis are common complications in untreated patients. Open or arthroscopic surgery is suitable while there is no consensus related to superiority of different approaches. We presented an arthroscopic treatment of a male patient, 48 years old with labrum tear and synovial chondromatosis localized in subacromial and subdeltoid region. Advantages of arthroscopic surgery in the presence of intra- and extra-articular combined pathologies are also discussed.
12. Arthroscopic Treatment of a Case with Concomitant Subacromial and Subdeltoid Synovial Chondromatosis and Labrum Tear
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Nevres Hurriyet Aydogan
2013-01-01
Full Text Available Synovial chondromatosis is a disease that seldomly seen in shoulder joint and is related to benign synovial proliferation and synchronous chondral tissue formation within the joint cavity. Patients suffer from progressive restriction of range of motion and shoulder pain. Extra-articular involvement is an extremely rare condition. Degenerative osteoarthritis, joint subluxation, and bursitis are common complications in untreated patients. Open or arthroscopic surgery is suitable while there is no consensus related to superiority of different approaches. We presented an arthroscopic treatment of a male patient, 48 years old with labrum tear and synovial chondromatosis localized in subacromial and subdeltoid region. Advantages of arthroscopic surgery in the presence of intra- and extra-articular combined pathologies are also discussed.
13. Short-Term Effectiveness of Precut Kinesiology Tape Versus an NSAID as Adjuvant Treatment to Exercise for Subacromial Impingement: A Randomized Controlled Trial.
Science.gov (United States)
Devereaux, Moira; Velanoski, Kinny Quan; Pennings, Amanda; Elmaraghy, Amr
2016-01-01
To compare the short-term effectiveness of precut kinesiology tape (PCT) to a nonsteroidal anti-inflammatory drug (NSAID) as adjuvant treatment to exercise physiotherapy in improving pain and function in patients with shoulder impingement. Randomized, controlled assessor-blind parallel-design trial with 3 groups. Academic-community hospital. One hundred patients (mean age: 48 ± 12.3, 61 men, 39 women) with a diagnosis of subacromial impingement (SAI) syndrome were randomized to a treatment group from October 2009 to June 2012. Eighty-one patients completed the study. Patients were randomized to one of the 3 treatment groups: PCT and Exercise (n = 33), NSAID and Exercise (n = 29), or Exercise only (n = 38) for a 4 session 2-week intervention with a registered physiotherapist. Numeric pain rating scales for pain at rest and pain with arm elevation, the Simple Shoulder Test (SST), and the Constant Score were assessed pretreatment and post-treatment. A statistically significant reduction in pain at rest and pain with arm elevation, as well as improvement in SST and Constant Score were observed in all 3 treatment groups, with minimal clinically important differences shown on pain with elevation and SST scores. Between-group differences on all outcome measures were not statistically significant or clinically meaningful. The improvements in pain and function observed with an NSAID or PCT as adjuvant treatments were no greater than with rehabilitation exercise alone. If adjuvant treatment is desired, PCT seems to be better tolerated than an NSAID, although the difference did not reach significance. The routine addition of adjuvant treatment is not supported by the results of this study. As adjuvant therapy, PCT seems to be better tolerated than an NSAID. If desired, clinicians may consider incorporating PCT along with an exercise component in the conservative treatment of SAI syndrome.
14. High-resolution ultrasound of rotator cuff and biceps reflection pulley in non-elite junior tennis players: anatomical study.
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Tagliafico, Alberto; Cadoni, Angela; Bignotti, Bianca; Martinoli, Carlo
2014-07-18
Tennis is believed to be potentially harmful for the shoulder, therefore the purpose of this study is to evaluate the anatomy of the rotator cuff and the coraco-humeral ligament (CHL) in a-symptomatic non-elite junior tennis players with high-resolution ultrasound (US). From August 2009 to September 2010 n = 90 a-symptomatic non-elite junior tennis players (mean age ± standard deviation: 15 ± 3) and a control group of age- and sex- matched subjects were included. Shoulder assessment with a customized standardized protocol was performed. Body mass index, dominant arm, years of practice, weekly hours of training, racket weight, grip (Eastern, Western and semi-Western), kind of strings were recorded. Abnormalities were found at ultrasound in 14/90 (15%) players. Two players had supraspinatus tendinosis, two had subacromial impingement and ten had subacromial bursitis. CHL thickness resulted comparable in the dominant and non-dominant arms (11.3 ± 4.4 mm vs. 13 ± 4.2, p > 0.05). Multivariate analysis demonstrated that no association was present among CHL thickness and the variables evaluated. In the control group, abnormalities were found at ultrasound in 6/60 (10%) subjects (sub-acromial bursitis). No statistically significant differences between players and control group were found (p = 0.71). In a-symptomatic non-elite junior tennis players only minor shoulder abnormalities were found.
15. Rotating Wavepackets
Science.gov (United States)
Lekner, John
2008-01-01
Any free-particle wavepacket solution of Schrodinger's equation can be converted by differentiations to wavepackets rotating about the original direction of motion. The angular momentum component along the motion associated with this rotation is an integral multiple of [h-bar]. It is an "intrinsic" angular momentum: independent of origin and…
16. Rotational elasticity
Science.gov (United States)
Vassiliev, Dmitri
2017-04-01
We consider an infinite three-dimensional elastic continuum whose material points experience no displacements, only rotations. This framework is a special case of the Cosserat theory of elasticity. Rotations of material points are described mathematically by attaching to each geometric point an orthonormal basis that gives a field of orthonormal bases called the coframe. As the dynamical variables (unknowns) of our theory, we choose the coframe and a density. We write down the general dynamic variational functional for our rotational theory of elasticity, assuming our material to be physically linear but the kinematic model geometrically nonlinear. Allowing geometric nonlinearity is natural when dealing with rotations because rotations in dimension three are inherently nonlinear (rotations about different axes do not commute) and because there is no reason to exclude from our study large rotations such as full turns. The main result of the talk is an explicit construction of a class of time-dependent solutions that we call plane wave solutions; these are travelling waves of rotations. The existence of such explicit closed-form solutions is a non-trivial fact given that our system of Euler-Lagrange equations is highly nonlinear. We also consider a special case of our rotational theory of elasticity which in the stationary setting (harmonic time dependence and arbitrary dependence on spatial coordinates) turns out to be equivalent to a pair of massless Dirac equations. The talk is based on the paper [1]. [1] C.G.Boehmer, R.J.Downes and D.Vassiliev, Rotational elasticity, Quarterly Journal of Mechanics and Applied Mathematics, 2011, vol. 64, p. 415-439. The paper is a heavily revised version of preprint https://arxiv.org/abs/1008.3833
17. Exercise therapy is evidence-based treatment of shoulder impingement syndrome. Current practice or recommendation only.
Science.gov (United States)
Ylinen, J; Vuorenmaa, M; Paloneva, J; Kiviranta, I; Kautiainen, H; Oikari, M; Häkkinen, A
2013-08-01
18. Utilizing the metabolic syndrome component count in workers’ health surveillance: An example of day-time vs. day-night rotating shift workers
Directory of Open Access Journals (Sweden)
Yu Cheng Lin
2015-08-01
Full Text Available Objectives: To establish a practical method for assessing the general metabolic health conditions among different employee groups, this study utilized the total count of metabolic syndrome (MetS elements as a parameter, and performed a retrospective analysis comparing changes of MetS component count (MSC of 5 years among day-time work (DW and day-andnight rotating shift work (RSW employees. Material and Methods: The data of personal histories, physical examinations, blood tests, abdominal sonographic examinations and occupational records were collected from a cohort of workers in an electronics manufacturing company. We first defined the arithmetic mean value of MSC as MSC density (MSCD for the employee group; then we compared the changes of MSCD over 5 years between DW and RSW workers. Occupational, personal and health records were analyzed for the 1077 workers with an initial mean age of 32.4 years (standard deviation (SD: 6.2 years, including 565 RSW workers (52%. Results: The initial MSCDs were 1.26 and 1.12 (p = 0.06 for DW and RSW workers, respectively; after 5 years, the increments of MSCD for DW and RSW workers were 0.10 and 0.39, respectively (p < 0.01. By performing multivariate logistic regression analyses, and comparing with DW co-workers, final results indicated that the workers exposed to RSW have 1.7-fold increased risk of elevated MSCD (95% confidence interval (CI: 1.28–2.25, p < 0.01; and are 38% less likely (adjusted rate ratio (aRR 0.62, 95% CI: 0.45–0.86, p < 0.01 to attain decreased MSCD. Conclusions: These observations demonstrate that changes of MSCD are significantly different between DW and RSW workers, and are increasingly associated with RSW exposure. In conclusion, MSCD can represent the general metabolic health conditions of a given employee group; MSC, MSCD and their transitional changes can be applied as simple and standardized tools for monitoring metabolic health risk profiles when managing employee health
19. Dynamic Three-Dimensional Shoulder Mri during Active Motion for Investigation of Rotator Cuff Diseases.
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Christine Tempelaere
Full Text Available MRI is the standard methodology in diagnosis of rotator cuff diseases. However, many patients continue to have pain despite treatment, and MRI of a static unloaded shoulder seems insufficient for best diagnosis and treatment. This study evaluated if Dynamic MRI provides novel kinematic data that can be used to improve the understanding, diagnosis and best treatment of rotator cuff diseases.Dynamic MRI provided real-time 3D image series and was used to measure changes in the width of subacromial space, superior-inferior translation and anterior-posterior translation of the humeral head relative to the glenoid during active abduction. These measures were investigated for consistency with the rotator cuff diseases classifications from standard MRI.The study included: 4 shoulders with massive rotator cuff tears, 5 shoulders with an isolated full-thickness supraspinatus tear, 5 shoulders with tendinopathy and 6 normal shoulders. A change in the width of subacromial space greater than 4mm differentiated between rotator cuff diseases with tendon tears (massive cuff tears and supraspinatus tear and without tears (tendinopathy (p = 0.012. The range of the superior-inferior translation was higher in the massive cuff tears group (6.4mm than in normals (3.4mm (p = 0.02. The range of the anterior-posterior translation was higher in the massive cuff tears (9.2 mm and supraspinatus tear (9.3 mm shoulders compared to normals (3.5mm and tendinopathy (4.8mm shoulders (p = 0.05.The Dynamic MRI enabled a novel measure; 'Looseness', i.e. the translation of the humeral head on the glenoid during an abduction cycle. Looseness was better able at differentiating different forms of rotator cuff disease than a simple static measure of relative glenohumeral position.
20. Evidence that central sensitisation is present in patients with shoulder impingement syndrome and influences the outcome after surgery.
Science.gov (United States)
Gwilym, S E; Oag, H C L; Tracey, I; Carr, A J
2011-04-01
Impingement syndrome in the shoulder has generally been considered to be a clinical condition of mechanical origin. However, anomalies exist between the pathology in the subacromial space and the degree of pain experienced. These may be explained by variations in the processing of nociceptive inputs between different patients. We investigated the evidence for augmented pain transmission (central sensitisation) in patients with impingement, and the relationship between pre-operative central sensitisation and the outcomes following arthroscopic subacromial decompression. We recruited 17 patients with unilateral impingement of the shoulder and 17 age- and gender-matched controls, all of whom underwent quantitative sensory testing to detect thresholds for mechanical stimuli, distinctions between sharp and blunt punctate stimuli, and heat pain. Additionally Oxford shoulder scores to assess pain and function, and PainDETECT questionnaires to identify 'neuropathic' and referred symptoms were completed. Patients completed these questionnaires pre-operatively and three months post-operatively. A significant proportion of patients awaiting subacromial decompression had referred pain radiating down the arm and had significant hyperalgesia to punctate stimulus of the skin compared with controls (unpaired t-test, p shoulder pain associated with impingement. Also, if patients had relatively high levels of central sensitisation pre-operatively, as indicated by higher levels of punctate hyperalgesia and/or referred pain, the outcome three months after subacromial decompression was significantly worse.
1. Comparison of the Efficacy of Local Corticosteroid Injection and Physical Therapy on Pain Severity, Joint Range of Motion and Muscle Strength in Patients with Shoulder Impingement Syndrome Referred to Rasool-e-Akram Medical Center from April 2008 to September 2009
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Hosein Farahini
2011-11-01
Full Text Available Backgrounds: Subacromial impingement is a common cause of shoulder pain and many patients with this condition recover with conservative management. The most commonly used modalities of nonoperative treatment include activity modification, anti-inflammatory medication and subacromial injection of steroid and ultrasound and physical therapy programs. This study assessed the value of physiotherapy versus subacromial corticosteroid injection in patients with shoulder impingement syndrome (SIS. Methods: Seventy three patients with SIS enrolled in the study and treated through physiotherapy (n=37 and subacromial corticosteroid injection (n=36. Two follow-up sessions accomplished at the end of 4th week and 3rd month of treatment respectively. Results: Corticosteroid injection caused dramatic improvement in the painful state (p<0.0001 and sleep dysfunction score (p=0.039 in the first follow-up. However, physiotherapy showed significantly better results regarding patients’ pain score (p=0.016 and their shoulder join range of motions (p=0.017 and p=0.029 for the abduction and extension, respectively in their second follow-up. Conclusion: Our study results showed that subacromial corticosteroid injection primarily resulted in more improvement in the impingement symptoms. However, with the long-term follow-up the results were better for the physiotherapy. These results suggest that patients should not undergo surgery before having conservative treatment.
2. Prevalence of subacromial-subdeltoid bursitis in shoulder pain: an ultrasonographic study.
Science.gov (United States)
Draghi, Ferdinando; Scudeller, Luigia; Draghi, Anna Guja; Bortolotto, Chandra
2015-06-01
The presence of the subacromial-subdeltoid (SASD) bursa inflammation has recently been proposed as a primary radiologic factor predicting persistent limitation and pain in operated patients. The aim of the study was to verify the hypothesis that pain, or increased shoulder pain, could be associated with SASD bursitis not only in operated patients but also in general population. A consecutive series of 1940 shoulder ultrasound examinations were performed by our Department over a 5-year period using linear multi-frequency probes. All reports of examination executed for shoulder pain were reviewed. The video clips were independently reviewed by two radiologists: effusion in the SASD bursa and the presence of other pathological conditions were evaluated and confirmed. A total of 1147 shoulder video clips were re-evaluated, and 1587 pathologies were detected; 65.5 % of patients had only one pathology, 30.4 % had two and 4.1 % presented three pathologies. The difference between the group with and without effusion is statistically significant for acromioclavicular joint arthritis, supraspinatus tendon calcific tendinopathy, full-thickness and superficial tear of the supraspinatus, traumas and rheumatoid arthritis with a p value <0.01. Our study shows that the effusion in the SASD bursa is frequently associated with shoulder pain often independently from the underlying pathology; further studies are needed to confirm the statistical significance of this relationship by clarifying possible confounding factors.
3. Relationship between acromial morphological variation and subacromial impingement: A three-dimensional analysis.
Science.gov (United States)
Li, Xinyu; Xu, Wei; Hu, Ning; Liang, Xi; Huang, Wei; Jiang, Dianming; Chen, Hong
2017-01-01
To evaluate the association of acromial morphology and subacromial impingement. Bilateral shoulder computed tomography was performed in 138 patients who received shoulder arthroscopy. Measured parameters included: acromial tilt (AT), modified acromial tilt (mAT), acromial slope (AS), acromiohumeral interval (AHI), lateral acromial angle (LAA), acromial index (AI), critical shoulder angle (CSA), acromial anterior protrusion (AAP), and acromial inferior protrusion (AIP). Acromial morphological characteristics were compared between groups. Side-to-side differences were assessed between affected and non-affected shoulders. Intra- and inter-observer agreements for each parameter were calculated. AT (25.90 vs. 29.41°), mAT (18.88 vs. 22.64°), and AHI (5.46 vs. 6.47 mm) were significantly smaller in impinged patients. The impingement group demonstrated significantly larger AI (63.50 vs. 59.84%), CSA (31.78 vs. 28.74°), AAP (7.13 vs. 5.32 mm), and AIP (5.51 vs. 4.04 mm). Regarding side-to-side comparison, the acromial morphology was significantly different between the affected and non-affected shoulders in impinged patients, while the difference was slight and insignificant in control patients. All, except AS and LAA, measured parameters demonstrated good intra- and inter-observer agreements. Three-dimensional reconstructed CT scan is a reliable method to measure shoulder morphology. The acromial morphological variation is related with sub acromial impingement, however, the causal relationship of them should be further explored.
4. Electrotherapy modalities for rotator cuff disease.
Science.gov (United States)
Page, Matthew J; Green, Sally; Mrocki, Marshall A; Surace, Stephen J; Deitch, Jessica; McBain, Brodwen; Lyttle, Nicolette; Buchbinder, Rachelle
2016-06-10
Management of rotator cuff disease may include use of electrotherapy modalities (also known as electrophysical agents), which aim to reduce pain and improve function via an increase in energy (electrical, sound, light, or thermal) into the body. Examples include therapeutic ultrasound, low-level laser therapy (LLLT), transcutaneous electrical nerve stimulation (TENS), and pulsed electromagnetic field therapy (PEMF). These modalities are usually delivered as components of a physical therapy intervention. This review is one of a series of reviews that form an update of the Cochrane review, 'Physiotherapy interventions for shoulder pain'. To synthesise available evidence regarding the benefits and harms of electrotherapy modalities for the treatment of people with rotator cuff disease. We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 3), Ovid MEDLINE (January 1966 to March 2015), Ovid EMBASE (January 1980 to March 2015), CINAHL Plus (EBSCOhost, January 1937 to March 2015), ClinicalTrials.gov and the WHO ICTRP clinical trials registries up to March 2015, unrestricted by language, and reviewed the reference lists of review articles and retrieved trials, to identify potentially relevant trials. We included randomised controlled trials (RCTs) and quasi-randomised trials, including adults with rotator cuff disease (e.g. subacromial impingement syndrome, rotator cuff tendinitis, calcific tendinitis), and comparing any electrotherapy modality with placebo, no intervention, a different electrotherapy modality or any other intervention (e.g. glucocorticoid injection). Trials investigating whether electrotherapy modalities were more effective than placebo or no treatment, or were an effective addition to another physical therapy intervention (e.g. manual therapy or exercise) were the main comparisons of interest. Main outcomes of interest were overall pain, function, pain on motion, patient-reported global assessment of treatment success
5. Efectividad del tratamiento invasivo de los puntos gatillo miofasciales en la mejora del dolor y el ROM en pacientes diagnosticados de síndrome de pinzamiento subacromial.
OpenAIRE
Ropero Tena, Eric
2015-01-01
¿Es el tratamiento invasivo de punción seca una intervención eficaz en el síndrome de pinzamiento subacromial para disminuir el dolor y aumentar el rango de movilidad articular? Objetivos: Valorar la efectividad a corto y largo plazo del tratamiento invasivo de los PGM en pacientes diagnosticados de síndrome de pinzamiento subacromial con más de 6 meses de persistencia de los síntomas. Metodología: Se realizará un estudio experimental de tipo ensayo clínico aleatorio controlado y de cie...
6. Estudio sobre la eficacia de la educación y los ejercicios terapéuticos en el tratamiento del síndrome subacromial.
OpenAIRE
Vidal Prat, Núria
2014-01-01
OBJETIVO: Valorar la eficacia de la educación y los ejercicios terapéuticos en el síndrome subacromial. MATERIAL Y METODOS: Se realizará un estudio en sujetos diagnosticados de síndrome subacromial entre 35 y 70 años de edad, derivados al servicio de rehabilitación del Hospital Santa Maria de Lleida. Ensayo controlado aleatorio, con muestreo consecutivo de duración de 6 meses. El programa de intervención con un periodo de duración de 3 semanas, estará compuesto por un grupo control que per...
7. Lidocaine Test Increases the Success Rates of Corticosteroid Injection in Impingement Syndrome.
Science.gov (United States)
Kim, Sang Jun; Lee, Hyo Sun
2016-10-01
To determine whether lidocaine test injections would increase the success rate of corticosteroid injection for treatment of impingement syndrome. Two hundred thirty-nine patients diagnosed with impingement syndrome were allocated to the lidocaine test (LC) group (N = 139) and the subacromial (SA) group (N = 100). The LC group received 1 ml of 1% lidocaine injection into the subacromial bursa under ultrasound guidance and a second injection of the steroid solution into the subacromial bursa or glenohumeral joint according to the response. The SA group received the same amount of steroid injection into the subacromial bursa without a prior lidocaine injection. Categorical outcomes were utilized and subjects were grouped based on percentage pain relief. Clinical improvement was expressed in terms of the patient's global impression of change (PGIC) as 'not improved,' 'slightly improved,' and 'much improved. In the LC group, 76 of the 139 patients (54% [95 CI 46-63%]) showed '50-80% improvement' and 15 (11% [95% CI 6.6-17%]) patients showed 'more than 80% improvement' at 3 weeks after the injection. While in the SA group, 29 of the 100 patient (29% [95% CI 21-39%]) showed '50-80% improvement' and 13 (13% [95% CI 7.7-21%]) showed 'more than 80% 3 weeks after the injection (χ 2 = 15.073, P = 0.001). This difference persisted at 3 months (χ 2 = 8.015, P = 0.018). The chi-square test of PGIC at 3 weeks also showed significant differences (P lidocaine pre-injection increases the success rate of steroid injection in patients suspected of having impingement syndrome. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
8. Clinical anatomy of the subacromial and related shoulder bursae: A review of the literature.
Science.gov (United States)
Kennedy, Marion S; Nicholson, Helen D; Woodley, Stephanie J
2017-03-01
The subacromial bursa (SAB) is the main bursa of the shoulder. It facilitates normal movement and is also commonly involved in shoulder disorders. Other shoulder bursae have been described but their anatomy has not been well studied. Anatomical variation of shoulder bursae has been suggested and this has implications for clinical practice. This article reviews current knowledge of the normal anatomy of the SAB and related shoulder bursae. A systematic review of the English and German literature was conducted using databases and a hand search of reference lists focusing on the clinical anatomy of the SAB, coracobrachial and subcoracoid bursae and subtendinous bursa of subscapularis. Twenty-four original sources and 13 textbooks were identified. Fifteen studies described the general morphology of the shoulder bursae using cadaveric specimens, eight examined innervation, and one provided information about the blood supply of the SAB. The literature agrees that the SAB is consistent and well innervated with a lateral subdeltoid part and a variable subcoracoid portion. There is variability regarding the consistency, location, and communications of the coracobrachial and subcoracoid bursae and the superior part of the subtendinous bursa of subscapularis, and little information on their nerve and blood supply. Several bursae are present around the shoulder joint. Further research is warranted to understand the precise attachments, dimensions, and communications of the bursae, as well as their nerve and blood supply. This information will improve understanding of the clinical relevance of these bursae and inform appropriate assessment and treatment. Clin. Anat. 30:213-226, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
9. Distribution of the axillary nerve to the subacromial bursa and the area around the long head of the biceps tendon.
Science.gov (United States)
Nasu, H; Nimura, A; Yamaguchi, K; Akita, K
2015-09-01
Patients with a shoulder disorder often complain of pain on the anterior or lateral aspect of the shoulder. Such pain has been thought to originate from the suprascapular nerve. However, taking into consideration the distinctive course of the axillary nerve, the axillary nerve is likely to supply branches to the structure around the shoulder joint. This study was conducted to clarify the division, course, and distribution of the branches which originate from the axillary nerve and innervate structures around the shoulder joint. The division, course, and distribution of the branches which originate from the axillary nerve and innervate structures around the shoulder joint were examined macroscopically by dissecting 20 shoulders of 10 adult Japanese cadavers. The thin branches from the anterior branch of the axillary nerve were distributed to the subacromial bursa and the area around the long head of the biceps tendon. The branches from the main trunk of the axillary nerve or the branch to the teres minor muscle were distributed to the infero-posterior part of the shoulder joint. The pain on the anterior or lateral aspect of the shoulder, which has been thought to originate from the suprascapular nerve, might be related to the thin branches which originate from the axillary nerve and innervate the subacromial bursa and the area around the long head of the biceps tendon. These results would be useful to consider the cause of the shoulder pain or to prevent the residual pain after the biceps tenodesis.
10. A randomised controlled feasibility study investigating the use of eccentric and concentric strengthening exercises in the treatment of rotator cuff tendinopathy
Directory of Open Access Journals (Sweden)
Marcus Bateman
2014-01-01
Full Text Available Objectives: To conduct a feasibility study to compare concentric and eccentric rotator cuff strengthening exercises for rotator cuff tendinopathy. Methods: A total of 11 patients with rotator cuff tendinopathy who were on the waiting list for arthroscopic subacromial decompression surgery were randomised to perform eccentric rotator cuff strengthening exercises, concentric strengthening exercises or no exercises. Patients were evaluated in terms of levels of pain and function using the Oxford Shoulder Score and a Visual Analogue Scale initially, at 4 weeks and at 8 weeks. Results: The study design was found to be acceptable to patients and achieved a high level of 86% compliance. The drop-out rate was 0%. Two patients performing eccentric strengthening exercises improved sufficiently to cancel their planned surgery. Conclusion: Further research in this area is recommended. The study design was feasible and power calculations have been conducted to aid future research planning.
11. Rotator Cuff Exercises
Science.gov (United States)
... Home Prevention and Wellness Exercise and Fitness Injury Rehabilitation Rotator Cuff Exercises Rotator Cuff Exercises Share Print Rotator Cuff ... Best Rotator Cuff ExercisesNational Institutes of Health: MedlinePlus, ... and WellnessTags: Exercise Prescription, prevention, Shoulder Problems, ...
12. ARTHROSCOPIC TREATMENT OF SHOULDER IMPINGEMENT SYNDROME IN ONE-DAY HOSPITAL
Directory of Open Access Journals (Sweden)
Martin Mikek
2004-12-01
Full Text Available Background. Arthroscopic subacromial decompression is the method of choice in operative treatment of subacromial rotator cuff impingement. In General Hospital Novo mesto the procedure is performed on a basis of one-day surgery.Methods. We present a prospective analysis of results of operative treatment of shoulder impingement in 36 patients. In all patients functional shoulder scores according to Constant, SST and UCLA were recorded before the operative procedure and again at least three months after the index procedure.Results. According to acromial morphology in the observed group there were three patients with type I acromion (8%, 22 patients had type II acromion (61% and 11 had acromion type III (31%. The average Constant score improved from 21 (SD ± 15 before the operation to 78 (SD ± 12 after the operation and average SST score improved from 4,7 (SD ± 2 to 7,5 (SD ± 1.4 and average UCLA score from 11 (SD ± 3 to 26 (SD ± 3.Conclusions. We conclude that arthroscopic subacromial decompression in properly selected patients enables attainment of good or excellent results in over 90% of patients. Because of minimal invasivness the procedure can be safely performed as one-day surgery.
13. Assessment of dynamic humeral centering in shoulder pain with impingement syndrome: a randomised clinical trial.
Science.gov (United States)
Beaudreuil, Johann; Lasbleiz, Sandra; Richette, Pascal; Seguin, Gérard; Rastel, Christine; Aout, Mounir; Vicaut, Eric; Cohen-Solal, Martine; Lioté, Frédéric; de Vernejoul, Marie-Christine; Bardin, Thomas; Orcel, Philippe
2011-09-01
Treatment for degenerative rotator cuff disease of the shoulder includes physiotherapy. Dynamic humeral centering (DHC) aims at preventing subacromial impingement, which contributes to the disease. The goal of this study was to assess the effectiveness of DHC. 69 patients with shoulder pain and impingement syndrome were prospectively included in a single-centre randomised trial with a 12-month follow-up. Patients and assessor were blinded to the study hypothesis and treatment, respectively. DHC and non-specific mobilisation as control were performed for 6 weeks, in 15 supervised individual outpatient sessions, and patients performed daily home exercises. The planned primary outcome was the Constant score including subscores for pain, activity, mobility and strength at 3 months. Secondary outcomes were the Constant score and subscores at 12 months, and medication use for pain at 3 and 12 months. The DHC group did not differ from the control group in the total Constant score at 3 months. However, the DHC group showed a higher Constant subscore for pain (12.2 (SD 2.8) vs 9.9 (2.9), least square means difference 2.1, 95% CI 0.7 to 3.5, p=0.004). At 3 months, the DHC group also showed a higher rate of no medication use (96.7% vs 71%, proportional difference 25.7, 95% CI 3.7 to 51.9, p=0.012). There was no other intergroup difference. There was no difference in the total Constant score between DHC and controls. However, pain was improved at 3 months after DHC. The differences found in subscores for pain should be explored in future studies. Trial registration clinicaltrials.gov Identifier: NCT 01022775.
14. Assessment of the Postoperative Appearance of the Rotator Cuff Tendon Using Serial Sonography After Arthroscopic Repair of a Rotator Cuff Tear.
Science.gov (United States)
Yoo, Hye Jin; Choi, Ja-Young; Hong, Sung Hwan; Kang, Yusuhn; Park, Jina; Kim, Sae Hoon; Kang, Heung Sik
2015-07-01
The purpose of this study was to evaluate serial changes in sonographic findings of a rotator cuff tendon after rotator cuff repair. Sixty-five arthroscopically repaired rotator cuff tears (43 full-thickness tears and 22 partial-thickness tears) were retrospectively included in this study. Serial sonographic examinations were performed at 5 weeks, 3 months, and 6 months after surgery. The sonographic findings of the repaired tendon were assessed for a recurrent tear, tendon thickness, morphologic tendon characteristics, vascularity, and bursitis at each time point. Four recurrent tears occurred within 3 months of surgery. The postoperative tendon thickness decreased from 5 weeks to 6 months after surgery (P = .001). There were significant changes in the morphologic tendon characteristics, including the echo texture, fibrillar pattern, and surface irregularity of the repaired tendon, from 5 weeks to 6 months after surgery (P subacromial-subdeltoid bursitis and the vascularity of the repaired tendon decreased postoperatively over time. Serial sonography after arthroscopic rotator cuff repair was useful for monitoring the postoperative changes in a repaired tendon. The morphologic appearance of the repaired tendon and peritendinous soft tissue changes improved over time and nearly normalized within 6 months of surgery. © 2015 by the American Institute of Ultrasound in Medicine.
15. Treatments for Shoulder Impingement Syndrome
Science.gov (United States)
Dong, Wei; Goost, Hans; Lin, Xiang-Bo; Burger, Christof; Paul, Christian; Wang, Zeng-Li; Zhang, Tian-Yi; Jiang, Zhi-Chao; Welle, Kristian; Kabir, Koroush
2015-01-01
Abstract Many treatments for shoulder impingement syndrome (SIS) are available in clinical practice; some of which have already been compared with other treatments by various investigators. However, a comprehensive treatment comparison is lacking. Several widely used electronic databases were searched for eligible studies. The outcome measurements were the pain score and the Constant–Murley score (CMS). Direct comparisons were performed using the conventional pair-wise meta-analysis method, while a network meta-analysis based on the Bayesian model was used to calculate the results of all potentially possible comparisons and rank probabilities. Included in the meta-analysis procedure were 33 randomized controlled trials involving 2300 patients. Good agreement was demonstrated between the results of the pair-wise meta-analyses and the network meta-analyses. Regarding nonoperative treatments, with respect to the pain score, combined treatments composed of exercise and other therapies tended to yield better effects than single-intervention therapies. Localized drug injections that were combined with exercise showed better treatment effects than any other treatments, whereas worse effects were observed when such injections were used alone. Regarding the CMS, most combined treatments based on exercise also demonstrated better effects than exercise alone. Regarding surgical treatments, according to the pain score and the CMS, arthroscopic subacromial decompression (ASD) together with treatments derived from it, such as ASD combined with radiofrequency and arthroscopic bursectomy, showed better effects than open subacromial decompression (OSD) and OSD combined with the injection of platelet-leukocyte gel. Exercise therapy also demonstrated good performance. Results for inconsistency, sensitivity analysis, and meta-regression all supported the robustness and reliability of these network meta-analyses. Exercise and other exercise-based therapies, such as kinesio taping
16. Rotating Cavitation Supression Project
Data.gov (United States)
National Aeronautics and Space Administration — FTT proposes development of a rotating cavitation (RC) suppressor for liquid rocket engine turbopump inducers. Cavitation instabilities, such as rotating cavitation,...
17. Surgery for subacromial impingement syndrome in relation to intensities of occupational mechanical exposures across 10-year exposure time windows
DEFF Research Database (Denmark)
Dalbøge, Annett; Frost, Poul; Andersen, Johan Hviid
2017-01-01
if exposure to hand-arm vibration (HAV) is an independent risk factor. METHODS: We used data from a register-based cohort study of the entire Danish working population (n=2 374 403). During follow-up (2003-2008), 14 118 first-time events of surgery for SIS occurred. For each person, we linked register......-based occupational codes (1993-2007) to a general population job exposure matrix to obtain year-by-year exposure intensities on measurement scales for force, upper arm elevation >90° and repetition and expert rated intensities of exposure to HAV. For 10-year exposure time windows, we calculated the duration...... intensities for repetition. Any intensities of force and upper arm elevation >90° above minimal implied an increased risk across 10-year exposure time windows. No independent associations were found for HAV....
18. Risk of surgery for subacromial impingement syndrome in relation to neck-shoulder complaints and occupational biomechanical exposures
DEFF Research Database (Denmark)
Svendsen, Susanne Wulff; Dalbøge, Annett; Andersen, JH
2013-01-01
at the Danish Ramazzini Centre. We linked baseline questionnaire information from 1993-2004 on neck-shoulder complaints, job titles, psychosocial work factors, body mass index, and smoking with register information on first-time surgery for SIS from 1996-2008. Biomechanical exposure measures were obtained from...
19. Magnetic resonance imaging evaluation of muscle usage associated with three exercises for rotator cuff rehabilitation.
Science.gov (United States)
Horrigan, J M; Shellock, F G; Mink, J H; Deutsch, A L
1999-10-01
Methods of determining muscle usage for exercises involving rotator cuff muscles are limited. Therefore, this investigation used magnetic resonance imaging (MRI) to evaluate the effect of three different exercises used for rehabilitation of the rotator cuff. Five normal volunteer subjects (3 men, 2 women, mean age 31.4 yr) were studied. The exercises were scaption with internal rotation (SIR), military press (MP), and side-lying 45 degrees abduction (SLA). MR imaging was performed immediately before and after exercise using a "fast" spin echo STIR sequence and oblique coronal plane imaging. Changes in signal intensity pre- and post-exercise were measured at comparable section locations for the MR images of the supraspinatus, infraspinatus, teres minor, subscapularis, deltoid, and trapezius. The SLA showed the greatest increase in signal intensity in all the muscles (percent change, P < 0.01) except for the trapezius, which was used more by the MP and SIR. None of the exercises activated the teres minor (percent change, P = not significant). These findings have important implications in efficacy of physical rehabilitation of the rotator cuff and avoidance of subacromial impingement exercise motions.
20. Multipotent Mesenchymal Stem Cells from Human Subacromial Bursa: Potential for Cell Based Tendon Tissue Engineering
Science.gov (United States)
Song, Na; Armstrong, April D.; Li, Feng; Ouyang, Hongsheng
2014-01-01
Rotator cuff injuries are a common clinical problem either as a result of overuse or aging. Biological approaches to tendon repair that involve use of scaffolding materials or cell-based approaches are currently being investigated. The cell-based approaches are focused on applying multipotent mesenchymal stem cells (MSCs) mostly harvested from bone marrow. In the present study, we focused on characterizing cells harvested from tissues associated with rotator cuff tendons based on an assumption that these cells would be more appropriate for tendon repair. We isolated MSCs from bursa tissue associated with rotator cuff tendons and characterized them for multilineage differentiation in vitro and in vivo. Human bursa was obtained from patients undergoing rotator cuff surgery and cells within were isolated using collagenase and dispase digestion. The cells isolated from the tissues were characterized for osteoblastic, adipogenic, chondrogenic, and tenogenic differentiation in vitro and in vivo. The results showed that the cells isolated from bursa tissue exhibited MSCs characteristics as evidenced by the expression of putative cell surface markers attributed to MSCs. The cells exhibited high proliferative capacity and differentiated toward cells of mesenchymal lineages with high efficiency. Bursa-derived cells expressed markers of tenocytes when treated with bone morphogenetic protein-12 (BMP-12) and assumed aligned morphology in culture. Bursa cells pretreated with BMP-12 and seeded in ceramic scaffolds formed extensive bone, as well as tendon-like tissue in vivo. Bone formation was demonstrated by histological analysis and immunofluorescence for DMP-1 in tissue sections made from the scaffolds seeded with the cells. Tendon-like tissue formed in vivo consisted of parallel collagen fibres typical of tendon tissues. Bursa-derived cells also formed a fibrocartilagenous tissue in the ceramic scaffolds. Taken together, the results demonstrate a new source of MSCs with a
1. Comparison of Anterior and Posterior Cortico-steroid Injections for Pain Relief and Functional Improvement in Shoulder Impingement Syndrome.
Science.gov (United States)
Ramappa, Arun; Walley, Kempland C; Herder, Lindsay M; Iyer, Sravisht; Zurakowski, David; Hall, Amber; DeAngelis, Joseph P
Subacromial impingement syndrome (SIS) is the most common cause of shoulder pain. Treatment options for SIS include conservative modalities such as use of nonsteroidal anti-inflammatory drugs, physical therapy, and subacromial corticosteroid injections (CSIs). Although studies have found improvement in pain, function, and range of motion after CSI, the effect of injection route (anterior or posterior) on shoulder pain in patients with SIS has not been investigated. In the study reported here, patients were randomly assigned to 2 treatment groups: anterior CSI and posterior CSI. Pain was assessed with a visual analog scale (VAS) and function with the Single Assessment Numeric Evaluation (SANE). Patients were evaluated before injection (baseline) and 1, 3, and 6 months after injection. Of the 55 patients enrolled, 25 received anterior CSI and 30 received posterior CSI. The 2 groups showed no significant difference in VAS pain at baseline or 1, 3, or 6 months after injection. SANE scores were statistically different at 3 months. Each group had significantly less pain and better function 1, 3, and 6 months after injection than at baseline. Age, sex, and body mass index did not significantly affect the efficacy of anterior or posterior CSIs. In patients with SIS, subacromial CSI reduces pain and improves function for up to 6 months. These effects are no different for anterior and posterior injection routes. As a result, clinicians should rely on their clinical acumen when selecting injection routes, as anterior and posterior are both beneficial.
2. Reverse Fosbury Flop Tear of the Rotator Cuff
Directory of Open Access Journals (Sweden)
Jérôme Tirefort
2017-01-01
Full Text Available Introduction. “Fosbury flop” tear is an avulsion of the posterosuperior rotator cuff from the bone with reversal healing on its medial bursal-side. This case report describes a unique variant of Fosbury flop tear with a lesion of the musculotendinous junction that healed, for its tendon part, on the anterior humerus and coracoid process. Case Presentation. A 62-year-old man developed a posttraumatic painful shoulder with active loss of range of motion. Magnetic resonance arthrography demonstrated a lesion of the musculotendinous junction of the supraspinatus with healing of the tendon on the above-mentioned structures (reverse Fosbury flop. During arthroscopic evaluation, tendon repair was not possible and a debridement to avoid subacromial and anterior impingement associated with a tenotomy of the long head of the biceps were carried out. One year postoperatively, the patient had complete range of motion and was satisfied with the clinical results. Discussion and Conclusion. Different Fosbury flop tears exist. Radiologists and orthopedic surgeons should be aware of these tear patterns as failure to recognize them may lead to inadequate treatment.
Science.gov (United States)
Okino, S; Miyaji, H; Matoba, M
1995-05-01
We describe a 21-year-old woman with left shoulder pain increased by desk work. Left subclavian angiography disclosed occlusion of the posterior circumflex humeral artery on abduction and external rotation of the arm, compatible with the previous reports of the quadrilateral space syndrome. This syndrome should be considered in patients with shoulder pain of unknown aetiology.
4. Effectiveness of ultrasound-guided injections combined with shoulder exercises in the treatment of subacromial adhesive bursitis.
Science.gov (United States)
Gasparre, Giuseppe; Fusaro, Isabella; Galletti, Stefano; Volini, Silvia; Benedetti, Maria Grazia
2012-05-01
The aim of this study was to evaluate whether the association of exercises for the shoulder with ultrasound-guided injection into the bursa significantly improves the treatment outcome in adhesive bursitis. Two groups of 35 patients, one treated with ultrasound-guided injection (UGI) and the other one with ultrasound-guided injection and home exercise program (UGI-exercise) for 1 month, were assessed for pain and shoulder function before treatment, 1 and 3 months post-treatment. Fourteen patients in UGI group and 23 patients in the UGI-exercises group were completely free of pain after 1 month (p = 0.031). At 3 months' follow-up, patients in the UGI-exercise group showed a significant improvement with respect to the other group (p = 0.005). No differences were found in function assessment. The UGI combined with shoulder exercises in the treatment of subacromial adhesive bursitis is effective to ensure a more frequent complete pain relief in the medium term.
5. Unusual lesions mimicking impingement syndrome in the shoulder joint - Think medially
Directory of Open Access Journals (Sweden)
Rohit Singh
2016-09-01
These are unusual causes that should be considered when investigating classical impingement syndrome and particularly those who may have failed to respond to decompression surgery. They highlight the potential value of looking beyond the sub-acromial space for causal lesions and in these cases, at a time when limited ultrasound investigation has become increasingly popular; MRI has clearly played an important and was essential in planning surgery as these lesions would not have been identified on USS. Even though the symptoms were classical.
6. [Chilaidity syndrome. Case report].
Science.gov (United States)
Candela, Stefano; Candela, Giancarlo; Di Libero, Lorenzo; Argano, Francesco; Romano, Ornella; Iannella, Iolanda
2012-01-01
Chilaidity syndrome is a mal position by bowel mal rotation o malfissation. It is more common in right side expecially in obese people. If asyimptomatic, the syndrome is an occasional comparison by radiology, surgical exploration by laparoscopy or autopsy, otherwise, if symptomatic, there are obstructive symptoms,abdominal pain, nausea, vomiting, abdominal distension, flatulence, breath, constipation and anorexia. Diagnosis is radiological. We present a rare case of this syndrome in a man with serious obstructive symptoms.
7. Rotational Preference in Gymnastics
National Research Council Canada - National Science Library
Heinen, Thomas; Jeraj, Damian; Vinken, Pia M; Velentzas, Konstantinos
2012-01-01
In gymnastics, most skills incorporate rotations about one or more body axes. At present, the question remains open if factors such as lateral preference and/or vestibulo-spinal asymmetry are related to gymnast's rotational preference...
8. On Averaging Rotations
DEFF Research Database (Denmark)
Gramkow, Claus
1999-01-01
In this article two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very offten the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... approximations to the Riemannian metric, and that the subsequent corrections are inherient in the least squares estimation. Keywords: averaging rotations, Riemannian metric, matrix, quaternion...
9. MRI of the rotator cuff and internal derangement.
Science.gov (United States)
Opsha, Oleg; Malik, Archana; Baltazar, Romulo; Primakov, Denis; Beltran, Salvador; Miller, Theodore T; Beltran, Javier
2008-10-01
Disease to the rotator cuff is the most common cause of shoulder pain and dysfunction in adults. This group of muscles performs multiple functions and is often stressed during various activities. The anatomy and physiology of the rotator cuff is complex and interconnected to other muscle groups in the shoulder. One must take the anatomic status of the rotator cuff tendons into account when planning the treatment of the rotator cuff injury. Diagnostic imaging of the rotator cuff, performed by MRI, provides valuable information about the nature of the injury. In this article, we will review the various types and causes of rotator cuff injuries, normal MR anatomy, function, patho-anatomy, and the biomechanics of the rotator cuff. We will also review shoulder impingement syndromes.
10. MRI of the rotator cuff and internal derangement
Energy Technology Data Exchange (ETDEWEB)
Opsha, Oleg [Department of Radiology, Maimonides Medical Center, 4802 10th Avenue, Brooklyn, NY 11219 (United States)], E-mail: oopsha@hotmail.com; Malik, Archana [Department of Radiology, Maimonides Medical Center, 4802 10th Avenue, Brooklyn, NY 11219 (United States)], E-mail: dr.armal@gmail.com; Baltazar, Romulo [Department of Radiology, Maimonides Medical Center, 4802 10th Avenue, Brooklyn, NY 11219 (United States)], E-mail: rbaltazar@gmail.com; Primakov, Denis [Department of Radiology, North Shore University Hospital, 300 Community Drive, Manhasset, NY 11030 (United States)], E-mail: dgprim@yahoo.com; Beltran, Salvador [Dr. Ramon Marti, 2 Albons, Ginrona 17136 (Spain); Miller, Theodore T. [Department of Radiology and Imaging, Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021 (United States)], E-mail: MillerTT@hss.edu; Beltran, Javier [Department of Radiology, Maimonides Medical Center, 4802 10th Avenue, Brooklyn, NY 11219 (United States)], E-mail: jbeltran46@msn.com
2008-10-15
Disease to the rotator cuff is the most common cause of shoulder pain and dysfunction in adults. This group of muscles performs multiple functions and is often stressed during various activities. The anatomy and physiology of the rotator cuff is complex and interconnected to other muscle groups in the shoulder. One must take the anatomic status of the rotator cuff tendons into account when planning the treatment of the rotator cuff injury. Diagnostic imaging of the rotator cuff, performed by MRI, provides valuable information about the nature of the injury. In this article, we will review the various types and causes of rotator cuff injuries, normal MR anatomy, function, patho-anatomy, and the biomechanics of the rotator cuff. We will also review shoulder impingement syndromes.
11. Acute Calcific Bursitis After Ultrasound-Guided Percutaneous Barbotage of Rotator Cuff Calcific Tendinopathy: A Case Report.
Science.gov (United States)
Kang, Bo-Sung; Lee, Seung Hak; Cho, Yung; Chung, Sun Gun
2016-08-01
Ultrasound-guided percutaneous barbotage is an effective treatment for rotator cuff calcific tendinopathy, providing rapid and substantial pain relief. We present the case of a 49-year-old woman with aggravated pain early after ultrasound-guided barbotage of a large calcific deposit in the supraspinatus tendon. Subsequent examination revealed a thick calcification spreading along the subacromial-subdeltoid bursa space, suggesting acute calcific bursitis complicated by barbotage. Additional barbotage alleviated her pain completely. Therefore, a high index of suspicion for acute calcific bursitis is required in patients with unresolved or aggravated pain after barbotage. Repeated barbotage could be effective for this condition. Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
12. Galaxy cluster's rotation
Science.gov (United States)
Manolopoulou, M.; Plionis, M.
2017-03-01
We study the possible rotation of cluster galaxies, developing, testing, and applying a novel algorithm which identifies rotation, if such does exist, as well as its rotational centre, its axis orientation, rotational velocity amplitude, and, finally, the clockwise or counterclockwise direction of rotation on the plane of the sky. To validate our algorithms we construct realistic Monte Carlo mock rotating clusters and confirm that our method provides robust indications of rotation. We then apply our methodology on a sample of Abell clusters with z ≲ 0.1 with member galaxies selected from the Sloan Digital Sky Survey DR10 spectroscopic data base. After excluding a number of substructured clusters, which could provide erroneous indications of rotation, and taking into account the expected fraction of misidentified coherent substructure velocities for rotation, provided by our Monte Carlo simulation analysis, we find that ∼23 per cent of our clusters are rotating under a set of strict criteria. Loosening the strictness of the criteria, on the expense of introducing spurious rotation indications, we find this fraction increasing to ∼28 per cent. We correlate our rotation indicators with the cluster dynamical state, provided either by their Bautz-Morgan type or by their X-ray isophotal shape and find for those clusters showing rotation within 1.5 h^{-1}_{70} Mpc that the significance of their rotation is related to the dynamically younger phases of cluster formation but after the initial anisotropic accretion and merging has been completed. Finally, finding rotational modes in galaxy clusters could lead to the necessity of correcting the dynamical cluster mass calculations.
13. Rotating Stars in Relativity
Directory of Open Access Journals (Sweden)
Stergioulas Nikolaos
2003-01-01
Full Text Available Rotating relativistic stars have been studied extensively in recent years, both theoretically and observationally, because of the information they might yield about the equation of state of matter at extremely high densities and because they are considered to be promising sources of gravitational waves. The latest theoretical understanding of rotating stars in relativity is reviewed in this updated article. The sections on the equilibrium properties and on the nonaxisymmetric instabilities in f-modes and r-modes have been updated and several new sections have been added on analytic solutions for the exterior spacetime, rotating stars in LMXBs, rotating strange stars, and on rotating stars in numerical relativity.
14. The spatial rotator
DEFF Research Database (Denmark)
Rasmusson, Allan; Hahn, Ute; Larsen, Jytte Overgaard
2013-01-01
This paper presents a new local volume estimator, the spatial rotator, which is based on measurements on a virtual 3D probe, using computer assisted microscopy. The basic design of the probe builds upon the rotator principle which requires only a few manual intersection markings, thus making...... the spatial rotator fast to use. Since a 3D probe is involved, it is expected that the spatial rotator will be more efficient than the the nucleator and the planar rotator, which are based on measurements in a single plane. An extensive simulation study shows that the spatial rotator may be more efficient...... than the traditional local volume estimators. Furthermore, the spatial rotator can be seen as a further development of the Cavalieri estimator, which does not require randomization of sectioning or viewing direction. The tissue may thus be sectioned in any arbitrary direction, making it easy...
15. Rilonacept in the treatment of subacromial bursitis: A randomized, non-inferiority, unblinded study versus triamcinolone acetonide.
Science.gov (United States)
Carroll, Matthew B; Motley, Spencer A; Wohlford, Susanna; Ramsey, Bryan C
2015-12-01
16. The relationship between subacromial bursa thickness on ultrasound and shoulder pain in open water endurance swimmers over time.
Science.gov (United States)
Couanis, G; Breidahl, W; Burnham, S
2015-07-01
To help clinicians understand the clinical relevance of subacromial bursa (SAB) thickness on ultrasound investigations in marathon swimmers. A prospective, observational cohort study. Twenty two open-water marathon swimmers entered in a 19.7km open-water event received comprehensive, bilateral, shoulder ultrasounds on three occasions: 4 months prior to the race, 2 weeks prior to the race and within 1 week after the race. The SAB thickness was measured in the longitudinal plane of supraspinatus, with other abnormailities also recorded. The swimmers completed questionnaires detailing presence and severity of shoulder pain, volume of swimming completed that week and their breathing pattern. SAB thickness increased with season progression: mean of 1.55 (± 0.68) 4 months prior to the race, 1.63 (± 0.68) 2 weeks prior to the race and 1.86 (± 0.69) 1 week after the race. SAB thickness is significantly (p=0.05) correlated (β=0.11) with kilometres swum in the pool in the preceding week. SAB thickness was not significantly correlated with pain when measured prior to the race. However, at 1 week post race, SAB thickness of shoulders with pain were significantly greater than those without pain, p-value=0.032. SAB thickness increases with increasing swimming training. Commonly, this increase is not correlated to pain, suggestive of a painless adaptive process. The significant correlation between pain and SAB thickness soon after an exacerbating event suggests that painful acute SAB thickening is a different entity to chronic, painless adaptive SAB thickening. These two entities can only be differentiated by clinical history and examination. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
17. US guided corticosteroid injection into the subacromial-subdeltoid bursa: Technique and approach.
Science.gov (United States)
Molini, L; Mariacher, S; Bianchi, S
2012-02-01
Local injection of cortisone derivatives, sometimes combined with local anesthetics, is frequently administered in rheumatology as the treatment of choice in para-articular diseases or as an adjuvant to systemic therapy in the treatment of arthritis.One of the most frequent local corticosteroid injections administered in daily clinical practice by rheumatologists, orthopedic surgeons, physiatrists, sports medicine doctors and general practitioners is injection into the subacromialsubdeltoid bursa in the treatment of bursitis and anterior superior impingement syndrome of the shoulder.Before local corticosteroid injection is administered, it is important to identify possible contraindications and to examine the documentation provided by the patient. Absolute contraindications or those related to the procedure should be evaluated by the prescribing physician but also the physician performing the corticosteroid injection should evaluate possible contraindications to make sure that corticosteroid injection is feasible. The present paper describes the ultrasound (US) guided local corticosteroid injection procedure with particular attention to the equipment required, the position of the patient and the examiner as well as the approach. The main advantage of US guidance during corticosteroid injection is the possibility to identify vascular structures, nerves and tendons situated in the needle path in order to avoid these structures and be sure to inject the drug into the appropriate location. When all rules are complied with and the corticosteroid injection is carried out by an experienced physician, it is virtually painless and is performed in just a few minutes.
18. US guided corticosteroid injection into the subacromial-subdeltoid bursa: Technique and approach
Science.gov (United States)
Molini, L.; Mariacher, S.; Bianchi, S.
2012-01-01
Local injection of cortisone derivatives, sometimes combined with local anesthetics, is frequently administered in rheumatology as the treatment of choice in para-articular diseases or as an adjuvant to systemic therapy in the treatment of arthritis. One of the most frequent local corticosteroid injections administered in daily clinical practice by rheumatologists, orthopedic surgeons, physiatrists, sports medicine doctors and general practitioners is injection into the subacromialsubdeltoid bursa in the treatment of bursitis and anterior superior impingement syndrome of the shoulder. Before local corticosteroid injection is administered, it is important to identify possible contraindications and to examine the documentation provided by the patient. Absolute contraindications or those related to the procedure should be evaluated by the prescribing physician but also the physician performing the corticosteroid injection should evaluate possible contraindications to make sure that corticosteroid injection is feasible. The present paper describes the ultrasound (US) guided local corticosteroid injection procedure with particular attention to the equipment required, the position of the patient and the examiner as well as the approach. The main advantage of US guidance during corticosteroid injection is the possibility to identify vascular structures, nerves and tendons situated in the needle path in order to avoid these structures and be sure to inject the drug into the appropriate location. When all rules are complied with and the corticosteroid injection is carried out by an experienced physician, it is virtually painless and is performed in just a few minutes. PMID:23396761
NARCIS (Netherlands)
Brentjens, MA; de Bruyn, AG
2005-01-01
We extend the rotation measure work of Burn ( 1966, MNRAS, 133, 67) to the cases of limited sampling of lambda(2) space and non-constant emission spectra. We introduce the rotation measure transfer function (RMTF), which is an excellent predictor of n pi ambiguity problems with the lambda(2)
20. CONTROL ROD ROTATING MECHANISM
Science.gov (United States)
Baumgarten, A.; Karalis, A.J.
1961-11-28
A threaded rotatable shaft is provided which rotates in response to linear movement of a nut, the shaft being surrounded by a pair of bellows members connected to either side of the nut to effectively seal the reactor from leakage and also to store up energy to shut down the reactor in the event of a power failure. (AEC)
1. Units of rotational information
Science.gov (United States)
Yang, Yuxiang; Chiribella, Giulio; Hu, Qinheping
2017-12-01
Entanglement in angular momentum degrees of freedom is a precious resource for quantum metrology and control. Here we study the conversions of this resource, focusing on Bell pairs of spin-J particles, where one particle is used to probe unknown rotations and the other particle is used as reference. When a large number of pairs are given, we show that every rotated spin-J Bell state can be reversibly converted into an equivalent number of rotated spin one-half Bell states, at a rate determined by the quantum Fisher information. This result provides the foundation for the definition of an elementary unit of information about rotations in space, which we call the Cartesian refbit. In the finite copy scenario, we design machines that approximately break down Bell states of higher spins into Cartesian refbits, as well as machines that approximately implement the inverse process. In addition, we establish a quantitative link between the conversion of Bell states and the simulation of unitary gates, showing that the fidelity of probabilistic state conversion provides upper and lower bounds on the fidelity of deterministic gate simulation. The result holds not only for rotation gates, but also to all sets of gates that form finite-dimensional representations of compact groups. For rotation gates, we show how rotations on a system of given spin can simulate rotations on a system of different spin.
2. Deconstructing Mental Rotation
DEFF Research Database (Denmark)
Larsen, Axel
2014-01-01
A random walk model of the classical mental rotation task is explored in two experiments. By assuming that a mental rotation is repeated until sufficient evidence for a match/mismatch is obtained, the model accounts for the approximately linearly increasing reaction times (RTs) on positive trials...
Science.gov (United States)
Le Vine, David
2016-01-01
Faraday rotation is a change in the polarization as signal propagates through the ionosphere. At L-band it is necessary to correct for this change and measurements are made on the spacecraft of the rotation angle. These figures show that there is good agreement between the SMAP measurements (blue) and predictions based on models (red).
4. Rotating stars in relativity.
Science.gov (United States)
Paschalidis, Vasileios; Stergioulas, Nikolaos
2017-01-01
Rotating relativistic stars have been studied extensively in recent years, both theoretically and observationally, because of the information they might yield about the equation of state of matter at extremely high densities and because they are considered to be promising sources of gravitational waves. The latest theoretical understanding of rotating stars in relativity is reviewed in this updated article. The sections on equilibrium properties and on nonaxisymmetric oscillations and instabilities in f -modes and r -modes have been updated. Several new sections have been added on equilibria in modified theories of gravity, approximate universal relationships, the one-arm spiral instability, on analytic solutions for the exterior spacetime, rotating stars in LMXBs, rotating strange stars, and on rotating stars in numerical relativity including both hydrodynamic and magnetohydrodynamic studies of these objects.
5. Rapidly rotating red giants
Science.gov (United States)
Gehan, Charlotte; Mosser, Benoît; Michel, Eric
2017-10-01
Stellar oscillations give seismic information on the internal properties of stars. Red giants are targets of interest since they present mixed modes, wich behave as pressure modes in the convective envelope and as gravity modes in the radiative core. Mixed modes thus directly probe red giant cores, and allow in particular the study of their mean core rotation. The high-quality data obtained by CoRoT and Kepler satellites represent an unprecedented perspective to obtain thousands of measurements of red giant core rotation, in order to improve our understanding of stellar physics in deep stellar interiors. We developed an automated method to obtain such core rotation measurements and validated it for stars on the red giant branch. In this work, we particularly focus on the specific application of this method to red giants having a rapid core rotation. They show complex spectra where it is tricky to disentangle rotational splittings from mixed-mode period spacings. We demonstrate that the method based on the identification of mode crossings is precise and efficient. The determination of the mean core rotation directly derives from the precise measurement of the asymptotic period spacing ΔΠ1 and of the frequency at which the crossing of the rotational components is observed.
6. Reliability of diagnostic tests in rotator cuff muscle pathology
Directory of Open Access Journals (Sweden)
2006-02-01
Full Text Available Background: Several tests to assist it in the diagnoses of rota-tor cuff impairment have been described in the literature but controversystill exists as to the accuracy of these tests. A study was therefore conducted to determine the reliability of the rotator cuff muscle tests (empty can, full can, lift off and external rotation as a diagnostic tool.Methodology: Fifty three patients experiencing shoulder pain were assessedusing manual muscle tests (empty can; full can; lift off and external rotationtests. Both pain and weakness were recorded using numerical scales adapted from tests performed by Itoi et al, (1999. These results were compared to ultrasonic diagnoses made by a surgeon. Informed consent was obtained and anonymity was ensured for all participants.Results: A test was false positive when ultrasonic diagnosis indicated no tear in the muscle (although oedema or calcification may have been present, but the manual muscle test was positive regarding pain and weakness. A test on the other hand was false negative when the ultrasonic diagnosis indicated a muscle tear but the manual muscle tests indicated no pain or muscle weakness. Reliability was tested using sensitivity and specificity tests. The sensitivity of all four tests was high (80%, but the specificity was low (20% to 40%, implying that a large number of false positive diagnoses can be made. The major contributors to the false positive results were sub-acromial sub-deltoid bursitis and a decreased acromio-humeral space. When considering pain alone for a positive result the correlation increased a little, however, taking both pain and muscle weakness into account, the correlation increased even more.Conclusion: The manual muscle tests were not as reliable as expected, but concurrent pathologies may be the main factor influencing the results of the tests. The combination of muscle strength and pain could be recommendedas criteria for a positive test. The empty can and full can
7. Rotating Stars in Relativity
Directory of Open Access Journals (Sweden)
Nikolaos Stergioulas
1998-06-01
Full Text Available Because of the information they can yield about the equation of state of matter at extremely high densities and because they are one of the more possible sources of detectable gravitational waves, rotating relativistic stars have been receiving significant attention in recentyears. We review the latest theoretical and numerical methods for modeling rotating relativistic stars, including stars with a strong magnetic field and hot proto-neutron stars. We also review nonaxisymmetric oscillations and instabilities in rotating stars and summarize the latest developments regarding the gravitational wave-driven (CFS instability in both polar and axial quasi-normal modes.
8. A rotating quantum vacuum
Energy Technology Data Exchange (ETDEWEB)
Lorenci, V.A. de; Svaiter, N.F. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)
1996-11-01
It was investigated which mapping has to be used to compare measurements made in a rotating frame to those made in an inertial frame. Using a non-Galilean coordinate transformation, the creation-annihilation operators of a massive scalar field in the rotating frame are not the same as those of an inertial observer. This leads to a new vacuum state(a rotating vacuum) which is a superposition of positive and negative frequency Minkowski particles. Polarization effects in circular accelerators in the proper frame of the electron making a connection with the inertial frame point of view were analysed. 65 refs.
9. Uso del taping en el manejo clínico de sujetos con pinzamiento sub-acromial: revisión sistemática
OpenAIRE
R. A. Aguilera Eguía; E. O. Zafra Santos; F. A. Araya Quintanilla; L. E. Gómez Carreño; J. X. Soto Aliaga; A. Vargas Varga; C. J. Cofré Bolados; A. R. Espinoza Salinas; G. A. Pavez von Martens; T. Aguilera Eguía; M. Di Santo
2014-01-01
El pinzamiento sub-acromial (SPS) es el trastorno músculo-esquelético más frecuente de las patologías de hombro. El taping se ha transformado en una indicación relativamente nueva y bastante común en los últimos años. Se realizará una síntesis de la evidencia a través de una revisión sistemática (RS) de ensayos clínicos aleatorizados que hayan comparado el uso del taping para el manejo de estos pacientes. El objetivo de esta revisión es determinar el efecto del taping sobre el dolor en sujeto...
10. Efectividad del kinesiotape como tratamiento complementario a un programa de ejercicio físico en el Síndrome del pinzamiento subacromial secundario a discinesias escapulares
OpenAIRE
2016-01-01
Aquest projecte té com a objectiu valorar l'efectivitat del kinesiotape com una tècnica complementària dins d’un programa d'exercici físic, en la funcionalitat dels treballadors, que utilitzen els seus braços per sobre del cap, d'entre 18-65 anys diagnosticats de síndrome del pinçament subacromial secundari a discinèsies escapulars. Per l’assoliment d’aquest objectiu es realitzarà un estudi multicèntric controlat i aleatoritzat amb doble cec sobre una mostra de 225 subjectes. En l'estudi hi h...
11. Ultrasound-guided versus blind subacromial-subdeltoid bursa injection in adults with shoulder pain: A systematic review and meta-analysis.
Science.gov (United States)
Wu, Tao; Song, Hai Xin; Dong, Yan; Li, Jian Hua
2015-12-01
This systematic review and meta-analysis aimed to assess the effectiveness of ultrasound-guided (USG) versus blind (landmark-guided, LMG) corticosteroid subacromial-subdeltoid bursa injection in adults with shoulder pain. The searches were performed on PubMed, Ovid MEDLINE, Ovid EMBASE, Ovid CochraneCENTRAL, Web of Science, Google Scholar, and Scopus from database inception through March 27, 2015. Studies were included trials comparing USG versus LSG injections for the treatment of adults with subacromial-subdeltoid bursitis. Two reviewers independently performed data extraction and appraisal of the studies. The outcome measures collected were the decreased VAS and SDQ scores, the increased shoulder function scores and shoulder abduction motion range, and the effective rate at 6 weeks after injection. Seven papers including 445 patients were reviewed; 224 received LMG injections and 221 received USG injections. There was a statistically significant difference in favor of USG for pain score [MD = 1.19, 95% CI (0.39, 1.98), P = 0.003] and SDQ score [MD = 5.01, 95% CI (1.82, 8.19), P = 0.02] at 6 weeks after injection. Also there was a statistically significant difference between the groups, with greater improvement reported of shoulder function scores [SMD = 0.89, 95% CI (0.56, 1.23), P < 0.001] and shoulder abduction motion range [MD 32.69, 95% CI (14.82, 50.56), P < 0.001] in the USG group. More effective rate was also reported with USG group and the difference was statistically significant [risk ratio = 1.6, 95% CI (1.02, 2.50), P = 0.04]. Ultrasound-guided corticosteroid injections potentially offer a significantly greater clinical improvement over blind SASD bursitis injections in adults with shoulder pain. Copyright © 2015. Published by Elsevier Inc.
12. Rotator Cuff Injuries
Science.gov (United States)
... cuff are common. They include tendinitis, bursitis, and injuries such as tears. Rotator cuff tendons can become ... cuff depends on age, health, how severe the injury is, and how long you've had the ...
13. Rotator cuff repair - slideshow
Science.gov (United States)
... presentations/100229.htm Rotator cuff repair - series—Normal anatomy To use the sharing features on this page, ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...
14. The Earth's rotation problem
Science.gov (United States)
Brumberg, V. A.; Ivanova, T. V.
2008-09-01
The aim of the present paper is to find the trigonometric solution of the equations of the Earth's rotation around its centre of mass in the form of polynomial trigonometric series (Poisson series) without secular and mixed therms. For that the techniques of the General Planetary Theory (GPT) ( Brumberg, 1995) and the Poisson Series Processor (PSP) (Ivanova, 1995) are used. The GPT allows to reduce the equations of the translatory motion of the major planets and the Moon and the equations of the Earth's rotation in Euler parameters to the secular system describing the evolution of the planetary and lunar orbits (independent of the Earth's rotation) and the evolution of the Earth's rotation (depending on the planetary and lunar evolution).
15. On Averaging Rotations
DEFF Research Database (Denmark)
Gramkow, Claus
2001-01-01
In this paper two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very often the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... to a non-linear manifold and re-normalization or orthogonalization must be applied to obtain proper rotations. These latter steps have been viewed as ad hoc corrections for the errors introduced by assuming a vector space. The article shows that the two approximative methods can be derived from natural...... approximations to the Riemannian metric, and that the subsequent corrections are inherent in the least squares estimation....
16. Rotating Workforce Scheduling
OpenAIRE
Granfeldt, Caroline
2015-01-01
Several industries use what is called rotating workforce scheduling. This often means that employees are needed around the clock seven days a week, and that they have a schedule which repeats itself after some weeks. This thesis gives an introduction to this kind of scheduling and presents a review of previous work done in the field. Two different optimization models for rotating workforce scheduling are formulated and compared, and some examples are created to demonstrate how the addition of...
17. Ipsilateral Rotational Autokeratoplasty
OpenAIRE
Yesim Altay
2016-01-01
Corneal opacity is a leading cause of monocular blindness, and corneal transplantation is the most commonly performed solid organ transplantation in the world. Keratoplasty techniques for corneal opacities include lamellar allokeratoplasty and penetrating allokeratoplasty. Ipsilateral rotational autokeratoplasty can be an effective alternative to penetrating allokeratoplasty for some patients with corneal scars. This procedure involves a rotation of the patient%u2019s own cornea to move opaci...
18. Electromagnetic rotational actuation.
Energy Technology Data Exchange (ETDEWEB)
Hogan, Alexander Lee
2010-08-01
There are many applications that need a meso-scale rotational actuator. These applications have been left by the wayside because of the lack of actuation at this scale. Sandia National Laboratories has many unique fabrication technologies that could be used to create an electromagnetic actuator at this scale. There are also many designs to be explored. In this internship exploration of the designs and fabrications technologies to find an inexpensive design that can be used for prototyping the electromagnetic rotational actuator.
19. Rotating superconductor magnet for producing rotating lobed magnetic field lines
Science.gov (United States)
Hilal, Sadek K.; Sampson, William B.; Leonard, Edward F.
1978-01-01
This invention provides a rotating superconductor magnet for producing a rotating lobed magnetic field, comprising a cryostat; a superconducting magnet in the cryostat having a collar for producing a lobed magnetic field having oppositely directed adjacent field lines; rotatable support means for selectively rotating the superconductor magnet; and means for energizing the superconductor magnet.
20. Serotonin syndrome
Science.gov (United States)
Hyperserotonemia; Serotonergic syndrome; Serotonin toxicity; SSRI - serotonin syndrome; MAO - serotonin syndrome ... brain area. For example, you can develop this syndrome if you take migraine medicines called triptans together ...
1. The prevalence of neovascularity in patients clinically diagnosed with rotator cuff tendinopathy
Directory of Open Access Journals (Sweden)
Raza Syed A
2009-12-01
Full Text Available Abstract Background Shoulder dysfunction is common and pathology of the rotator cuff tendons and subacromial bursa are considered to be a major cause of pain and morbidity. Although many hypotheses exist there is no definitive understanding as to the origin of the pain arising from these structures. Research investigations from other tendons have placed intra-tendinous neovascularity as a potential mechanism of pain production. The prevalence of neovascularity in patients with a clinical diagnosis of rotator cuff tendinopathy is unknown. As such the primary aim of this pilot study was to investigate if neovascularity could be identified and to determine the prevalence of neovascularity in the rotator cuff tendons and subacromial bursa in subjects with unilateral shoulder pain clinically assessed to be rotator cuff tendinopathy. The secondary aims were to investigate the association between the presence of neovascularity and pain, duration of symptoms, and, neovascularity and shoulder function. Methods Patients with a clinical diagnosis of unilateral rotator cuff tendinopathy referred for a routine diagnostic ultrasound (US scan in a major London teaching hospital formed the study population. At referral patients were provided with an information document. On the day of the scan (on average, at least one week later the patients agreeing to participate were taken through the consent process and underwent an additional clinical examination prior to undergoing a bilateral grey scale and colour Doppler US examination (symptomatic and asymptomatic shoulder using a Philips HDI 5000 Sono CT US machine. The ultrasound scans were performed by one of two radiologists who recorded their findings and the final assessment was made by a third radiologist blinded both to the clinical examination and the ultrasound examination. The findings of the radiologists who performed the scans and the blinded radiologist were compared and any disagreements were resolved
2. Manual therapy and exercise for rotator cuff disease.
Science.gov (United States)
Page, Matthew J; Green, Sally; McBain, Brodwen; Surace, Stephen J; Deitch, Jessica; Lyttle, Nicolette; Mrocki, Marshall A; Buchbinder, Rachelle
2016-06-10
43 trials. We were unable to perform any meta-analyses because of clinical heterogeneity or incomplete outcome reporting. One trial compared manual therapy and exercise with placebo (inactive ultrasound therapy) in 120 participants with chronic rotator cuff disease (high quality evidence). At 22 weeks, the mean change in overall pain with placebo was 17.3 points on a 100-point scale, and 24.8 points with manual therapy and exercise (adjusted mean difference (MD) 6.8 points, 95% confidence interval (CI) -0.70 to 14.30 points; absolute risk difference 7%, 1% fewer to 14% more). Mean change in function with placebo was 15.6 points on a 100-point scale, and 22.4 points with manual therapy and exercise (adjusted MD 7.1 points, 95% CI 0.30 to 13.90 points; absolute risk difference 7%, 1% to 14% more). Fifty-seven per cent (31/54) of participants reported treatment success with manual therapy and exercise compared with 41% (24/58) of participants receiving placebo (risk ratio (RR) 1.39, 95% CI 0.94 to 2.03; absolute risk difference 16% (2% fewer to 34% more). Thirty-one per cent (17/55) of participants reported adverse events with manual therapy and exercise compared with 8% (5/61) of participants receiving placebo (RR 3.77, 95% CI 1.49 to 9.54; absolute risk difference 23% (9% to 37% more). However adverse events were mild (short-term pain following treatment).Five trials (low quality evidence) found no important differences between manual therapy and exercise compared with glucocorticoid injection with respect to overall pain, function, active shoulder abduction and quality of life from four weeks up to 12 months. However, global treatment success was more common up to 11 weeks in people receiving glucocorticoid injection (low quality evidence). One trial (low quality evidence) showed no important differences between manual therapy and exercise and arthroscopic subacromial decompression with respect to overall pain, function, active range of motion and strength at six and
3. Diagnostic imaging of shoulder rotator cuff lesions
Directory of Open Access Journals (Sweden)
Nogueira-Barbosa Marcello Henrique
2002-01-01
Full Text Available Shoulder rotator cuff tendon tears were evaluated with ultrasonography (US and magnetic resonance imaging (MRI. Surgical or arthroscopical correlation were available in 25 cases. Overall costs were also considered. Shoulder impingement syndrome diagnosis was done on a clinical basis. Surgery or arthroscopy was considered when conservative treatment failure for 6 months, or when rotator cuff repair was indicated. Ultrasound was performed in 22 patients and MRI in 17 of the 25 patients. Sensitivity, specificity and accuracy were 80%, 100% and 90.9% for US and 90%, 100% and 94.12% for MRI, respectively. In 16 cases both US and MRI were obtained and in this subgroup statistical correlation was excellent (p< 0.001. We concluded that both methods are reliable for rotator cuff full thickness tear evaluation. Since US is less expensive, it could be considered as the screening method when rotator cuff integrity is the main question, and when well trained radiologists and high resolution equipment are available.
4. Deltoid muscular flap transfer for the treatment of irreparable rotator cuff tears
Directory of Open Access Journals (Sweden)
Justus Gille
2009-09-01
Full Text Available The purpose of this study was to evaluate the outcome of deltoid muscle flap transfer for the treatment of irreparable rotator cuff tears. In a retrospective study 20 consecutive patients were evaluated. The index procedure took place between 2000 and 2003. Fifteen patients were male, mean age was 62 years. Inclusion criterion was a rotator cuff defect Bateman grade IV. Exclusion criteria were smaller defects, shoulder instability and fractures of the injured shoulder. An open reconstruction with acromioplasty and a pedicled delta flap was performed. Follow up period was mean 42 months. Follow-up included clinical examination, Magnetic Resonance Imaging (MRI and the Constant and Simple (CS shoulder tests. According to the Constant shoulder test the results were good in 13 patients, fair in 5 and unsatisfactory in 2. The pre-operative Constant Score improved from mean 25.7 points (±5.3 to 72.3 (±7.8 at follow-up. The mean values for the subcategories of CS increased significantly from 3.9 to 14.4 points for pain and from 4.2 to 15.9 points for activities daily routine (p0.05. Results of the Simple Shoulder Test showed a significant increase of the mean values from pre-operative 4.3 to 14.7 points post-operatively. MRI showed a subacromial covering of the defect in all cases, all flaps where intact on MRI but always the flap showed marked fatty degeneration. In conclusion, the delta flap is a simple method for the repair of large defects of the rotator cuff leading to satisfying medium results.
5. Vibrations of rotating machinery
CERN Document Server
Matsushita, Osami; Kanki, Hiroshi; Kobayashi, Masao; Keogh, Patrick
2017-01-01
This book opens with an explanation of the vibrations of a single degree-of-freedom (dof) system for all beginners. Subsequently, vibration analysis of multi-dof systems is explained by modal analysis. Mode synthesis modeling is then introduced for system reduction, which aids understanding in a simplified manner of how complicated rotors behave. Rotor balancing techniques are offered for rigid and flexible rotors through several examples. Consideration of gyroscopic influences on the rotordynamics is then provided and vibration evaluation of a rotor-bearing system is emphasized in terms of forward and backward whirl rotor motions through eigenvalue (natural frequency and damping ratio) analysis. In addition to these rotordynamics concerning rotating shaft vibration measured in a stationary reference frame, blade vibrations are analyzed with Coriolis forces expressed in a rotating reference frame. Other phenomena that may be assessed in stationary and rotating reference frames include stability characteristic...
6. Ipsilateral Rotational Autokeratoplasty
Directory of Open Access Journals (Sweden)
Yesim Altay
2016-09-01
Full Text Available Corneal opacity is a leading cause of monocular blindness, and corneal transplantation is the most commonly performed solid organ transplantation in the world. Keratoplasty techniques for corneal opacities include lamellar allokeratoplasty and penetrating allokeratoplasty. Ipsilateral rotational autokeratoplasty can be an effective alternative to penetrating allokeratoplasty for some patients with corneal scars. This procedure involves a rotation of the patient%u2019s own cornea to move opacity out of the visual axis. An important consideration when selecting cases for rotational autokeratoplasty is the dimensions of the corneal scar. Although ipsilateral autokeratoplasty may not provide as good a quality of vision as penetrating allokeratoplasty because of higher astigmatism and reduced corneal pupillary clear zone, these disadvantages are often outweighed when the risk of allograft rejection is high, as in pediatric patients and those with vascularised corneas. This technique would at least partially resolve the issue of scarcity of donor corneal tissue in developing countries.
7. The optical rotator
DEFF Research Database (Denmark)
Tandrup, T; Gundersen, Hans Jørgen Gottlieb; Jensen, Eva B. Vedel
1997-01-01
further discuss the methods derived from this principle and present two new local volume estimators. The optical rotator benefits from information obtained in all three dimensions in thick sections but avoids over-/ underprojection problems at the extremes of the cell. Using computer-assisted microscopes......The optical rotator is an unbiased, local stereological principle for estimation of cell volume and cell surface area in thick, transparent slabs, The underlying principle was first described in 1993 by Kieu Jensen (T. Microsc. 170, 45-51) who also derived an estimator of length, In this study we...... the extra measurements demand minimal extra effort and make this estimator even more efficient when it comes to estimation of individual cell size than many of the previous local estimators, We demonstrate the principle of the optical rotator in an example (the cells in the dorsal root ganglion of the rat...
8. Rotation of Giant Stars
Science.gov (United States)
Kissin, Yevgeni; Thompson, Christopher
2015-07-01
The internal rotation of post-main sequence stars is investigated, in response to the convective pumping of angular momentum toward the stellar core, combined with a tight magnetic coupling between core and envelope. The spin evolution is calculated using model stars of initial mass 1, 1.5, and 5 {M}⊙ , taking into account mass loss on the giant branches. We also include the deposition of orbital angular momentum from a sub-stellar companion, as influenced by tidal drag along with the excitation of orbital eccentricity by a fluctuating gravitational quadrupole moment. A range of angular velocity profiles {{Ω }}(r) is considered in the envelope, extending from solid rotation to constant specific angular momentum. We focus on the backreaction of the Coriolis force, and the threshold for dynamo action in the inner envelope. Quantitative agreement with measurements of core rotation in subgiants and post-He core flash stars by Kepler is obtained with a two-layer angular velocity profile: uniform specific angular momentum where the Coriolis parameter {Co}\\equiv {{Ω }}{τ }{con}≲ 1 (here {τ }{con} is the convective time), and {{Ω }}(r)\\propto {r}-1 where {Co}≳ 1. The inner profile is interpreted in terms of a balance between the Coriolis force and angular pressure gradients driven by radially extended convective plumes. Inward angular momentum pumping reduces the surface rotation of subgiants, and the need for a rejuvenated magnetic wind torque. The co-evolution of internal magnetic fields and rotation is considered in Kissin & Thompson, along with the breaking of the rotational coupling between core and envelope due to heavy mass loss.
9. Short-Term Outcome of Combined Corticosteriod and Local ...
African Journals Online (AJOL)
Erah
treatment consists of physical therapy, rest and oral anti-inflammatory drugs2. Some other conditions causing painful shoulder are subacromial bursitis, degeneration of acromioclavicular joint, tendonitis, adhesive capsulitis, impingement syndrome and rotator cuff tears. Lack of appropriate examination and inadequate.
10. Usefulness of rehabilitation in patients with rotator cuff calcific tendinopathy after ultrasound-guided percutaneous treatment.
Science.gov (United States)
Abate, Michele; Schiavone, Cosima; Salini, Vincenzo
2015-01-01
To evaluate the efficacy of a specific rehabilitation program for patients in whom ultrasound-guided percutaneous treatment (UGPT) was performed for rotator cuff calcific tendinopathy (RCCT). In this prospective observational study, 86 patients (22 males and 64 females) with shoulder calcific tendinopathy treated with UGPT were enrolled. At the end of the procedure, a corticosteroid injection into the subacromial-subdeltoid bursa was performed. The patients were then asked to follow a specific rehabilitation protocol (2 times/week for 5 weeks) that focused on mobility, strength and function. At baseline and after 6 weeks, clinical parameters, visual analog scale (VAS) and Constant-Murley scale (CMS) scores and ultrasound (US) features were collected. The mean age of the patients was 48.9 ± 8.4 years and their mean BMI was 22.7 ± 2.1. Considering the whole cohort, the treatment was effective, with a significant decrease in the VAS score and an improvement in the CMS score. Thereafter, on the basis of the compliance to the rehabilitation program (by self-report), 53 and 33 patients were included in the rehabilitation group (Rehab group; performed exercises ≥2 times/week) and the No Rehab group (performed exercises rehabilitation program, was an effective treatment for RCCT. © 2014 S. Karger AG, Basel.
11. From the RSNA refresher courses: US of the rotator cuff: pitfalls, limitations, and artifacts.
NARCIS (Netherlands)
Rutten, M.J.C.M.; Jager, G.J.; Blickman, J.G.
2006-01-01
High-resolution ultrasonography (US) has gained increasing popularity as a diagnostic tool for assessment of the soft tissues in shoulder impingement syndrome. US is a powerful and accurate method for diagnosis of rotator cuff tears and other rotator cuff abnormalities, provided the examiner has a
12. From the RSNA refresher courses - US of the rotator cuff : Pitfalls, limitations, and artifacts
NARCIS (Netherlands)
Rutten, Matthieu J. C. M.; Jager, Gerrit J.; Blickman, Johan G.
2006-01-01
High-resolution ultrasonography (US) has gained increasing popularity as a diagnostic tool for assessment of the soft tissues in shoulder impingement syndrome. US is a powerful and accurate method for diagnosis of rotator cuff tears and other rotator cuff abnormalities, provided the examiner has a
13. The effect of coracoacromial ligament excision and acromioplasty on the amount of rotator cuff force production necessary to restore intact glenohumeral biomechanics.
Science.gov (United States)
Budoff, Jeffrey E; Lin, Cheng-Li; Hong, Chih-Kai; Chiang, Florence L; Su, Wei-Ren
2016-06-01
14. Shoulder surface temperature and bone scintigraphy findings in patients with rotator cuff tears
OpenAIRE
Koike, Yoichi; Sano, Hirotaka; Kinjyo, Takeshi; Imamura, Itaru; Masahiro, Onuma; Goto, Masako; Ooyama, Masamizu; Kita, Atushi; Itoi, Eiji
2011-01-01
Background Complex regional pain syndrome (CRPS) is one of the serious complications after surgical treatment of a rotator cuff tear. Both a measurement of body surface temperature and bone scintigraphy have been used as diagnostic tools for the early phase of CRPS.Unfortunately, few studies have been carried out that applied these methods to the patients after rotator cuff repair. Purposes To clarify both shoulder surface temperature and bone scintigraphy findings in patients with rotator cu...
15. Comorbidities in rotator cuff disease: a case-control study.
Science.gov (United States)
Titchener, Andrew G; White, Jonathan J E; Hinchliffe, Sally R; Tambe, Amol A; Hubbard, Richard B; Clark, David I
2014-09-01
16. Rotationally Actuated Prosthetic Hand
Science.gov (United States)
Norton, William E.; Belcher, Jewell G., Jr.; Carden, James R.; Vest, Thomas W.
1991-01-01
Prosthetic hand attached to end of remaining part of forearm and to upper arm just above elbow. Pincerlike fingers pushed apart to degree depending on rotation of forearm. Simpler in design, simpler to operate, weighs less, and takes up less space.
17. Rotational waves in geodynamics
Science.gov (United States)
Gerus, Artyom; Vikulin, Alexander
2015-04-01
The rotation model of a geoblock with intrinsic momentum was constructed by A.V. Vikulin and A.G. Ivanchin [9, 10] to describe seismicity within the Pacific Ocean margin. It is based on the idea of a rotational motion of geoblocks as the parts of the rotating body of the Earth that generates rotary deformation waves. The law of the block motion was derived in the form of the sine-Gordon equation (SG) [5, 9]; the dimensionless form of the equation is: δ2θ δ2θ δξ2 - δη2 = sinθ, (1) where θ = β/2, ξ = k0z and η = v0k0t are dimensionless coordinates, z - length of the chain of masses (blocks), t - time, β - turn angle, ν0 - representative velocity of the process, k0 - wave number. Another case analyzed was a chain of nonuniformly rotating blocks, with deviation of force moments from equilibrium positions μ, considering friction forces α along boundaries, which better matched a real-life seismic process. As a result, the authors obtained the law of motion for a block in a chain in the form of the modified SG equation [8]: δ2θ δ2θ δθ- δξ2 - δ η2 = sin θ+ α δη + μδ(ξ)sin θ (2)
18. The Spatiale Rotator
DEFF Research Database (Denmark)
Rasmusson, Allan
2009-01-01
The inherent demand for unbiasedness for some stereological estimators imposes a demand of not only positional uniform randomness but also isotropic randomness, i.e. directional uniform randomness. In order to comply with isotropy, one must perform a random rotation of the object of interest before...
19. Repair of the rotator cuff. Mini-open and arthroscopic repairs.
Science.gov (United States)
Norberg, F B; Field, L D; Savoie, F H
2000-01-01
The repair of rotator cuff tears by traditional open subacromial decompression and rotator cuff tendon reapproximation has proved successful in restoring function and decreasing pain, but open rotator cuff repair has some inherent disadvantages. Postoperative detachment of the deltoid repair has been reported and results in significant morbidity. The open technique may also require a longer period of limited motion resulting in greater stiffness. Arthroscopically assisted mini-open repairs and, more recently, completely arthroscopic repairs of the rotator cuff have been developed and increasingly are being applied. Both techniques avoid detachment of the deltoid. The mini-open and arthroscopic approaches to rotator cuff repair have the added benefit of arthroscopic evaluation of the glenohumeral joint. The mini-open technique has the advantage of allowing the direct visualization of the cuff repair and allows surgeons to place the stitches in an open fashion, which is familiar to all surgeons. The mini-open technique also allows the placement of tension-absorbing stitches in the rare cases that they are needed. Mini-open techniques also allow the choice of bone anchors or osseous tunnels for fixation. The completely arthroscopic cuff repair has several potential advantages over the open and mini-open cuff repair techniques; first is the decreased disruption of the soft tissues, which may result in less scarring and adhesions. The procedure is the most cosmetically appealing of the techniques. Reduced postoperative pain is also cited as an advantage but has been demonstrated only in a single, nonrandomized study. Finally, if technical difficulties arise, the conversion to a mini-open repair can be done easily. In a few studies, arthroscopic cuff repair techniques have shown promise as an alternative to mini-open or open repair, but these results have been at the hands of a few surgeons who have extensive experience in arthroscopy of the shoulder. In contrast, the
20. Strain effects on rotational property in nanoscale rotation system.
Science.gov (United States)
Huang, Jianzhang; Han, Qiang
2018-01-11
This paper presents a study of strain effects on nanoscale rotation system consists of double-walls carbon nanotube and graphene. It is found that the strain effects can be a real-time controlling method for nano actuator system. The strain effects on rotational property as well as the effect mechanism is studied systematically through molecular dynamics simulations, and it obtains valuable conclusions for engineering application of rotational property management of nanoscale rotation system. It founds that the strain effects tune the rotational property by influencing the intertube supporting effect and friction effect of double-walls carbon nanotube, which are two critical factors of rotational performance. The mechanism of strain effects on rotational property is investigated in theoretical level based on analytical model established through lattice dynamics theory. This work suggests great potentials of strain effects for nanoscale real-time control, and provides new ideas for design and application of real-time controllable nanoscale rotation system.
1. Wave-driven Rotation in Supersonically Rotating Mirrors
Energy Technology Data Exchange (ETDEWEB)
A. Fetterman and N.J. Fisch
2010-02-15
Supersonic rotation in mirrors may be produced by radio frequency waves. The waves produce coupled diffusion in ion kinetic and potential energy. A population inversion along the diffusion path then produces rotation. Waves may be designed to exploit a natural kinetic energy source or may provide the rotation energy on their own. Centrifugal traps for fusion and isotope separation may benefit from this wave-driven rotation.
2. Rotational spectrum of tryptophan
Energy Technology Data Exchange (ETDEWEB)
Sanz, M. Eugenia, E-mail: maria.sanz@kcl.ac.uk; Cabezas, Carlos, E-mail: ccabezas@qf.uva.es; Mata, Santiago, E-mail: santiago.mata@uva.es; Alonso, Josè L., E-mail: jlalonso@qf.uva.es [Grupo de Espectroscopia Molecular (GEM), Edificio Quifima, Laboratorios de Espectroscopia y Bioespectroscopia, Unidad Asociada CSIC, Parque Científico Uva, Universidad de Valladolid, 47011 Valladolid (Spain)
2014-05-28
The rotational spectrum of the natural amino acid tryptophan has been observed for the first time using a combination of laser ablation, molecular beams, and Fourier transform microwave spectroscopy. Independent analysis of the rotational spectra of individual conformers has conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The analysis of the {sup 14}N nuclear quadrupole coupling constants is of particular significance since it allows discrimination between structures, thus providing structural information on the orientation of the amino group. Both observed conformers are stabilized by an O–H···N hydrogen bond in the side chain and a N–H···π interaction forming a chain that reinforce the strength of hydrogen bonds through cooperative effects.
DEFF Research Database (Denmark)
Holtegård Nielsen, Steen Morten
the reciprocal of the socalled Coriolis parameter, and the length scale, which is known as the Rossby radius. Also, because of their limited width currents influenced by rotation are quite persistent. The flow which results from the introduction of a surface level discontinuity across a wide channel is discussed...... of the numerical model a mechanism for the generation of along-frontal instabilities and eddies is suggested. Also, the effect of an irregular bathymetry is studied.Together with observations of wind and water levels some of the oceanographical observations from the old lightvessels are used to study...... with the horizontal extent of many other parts of the Danish inland waters implies that the dynamics of these should also be discussed in terms of rotational effects....
4. Marginal deformations & rotating horizons
Science.gov (United States)
Anninos, Dionysios; Anous, Tarek; D'Agnolo, Raffaele Tito
2017-12-01
Motivated by the near-horizon geometry of four-dimensional extremal black holes, we study a disordered quantum mechanical system invariant under a global SU(2) symmetry. As in the Sachdev-Ye-Kitaev model, this system exhibits an approximate SL(2, ℝ) symmetry at low energies, but also allows for a continuous family of SU(2) breaking marginal deformations. Beyond a certain critical value for the marginal coupling, the model exhibits a quantum phase transition from the gapless phase to a gapped one and we calculate the critical exponents of this transition. We also show that charged, rotating extremal black holes exhibit a transition when the angular velocity of the horizon is tuned to a certain critical value. Where possible we draw parallels between the disordered quantum mechanics and charged, rotating black holes.
5. Isotropic stochastic rotation dynamics
Science.gov (United States)
Mühlbauer, Sebastian; Strobl, Severin; Pöschel, Thorsten
2017-12-01
Stochastic rotation dynamics (SRD) is a widely used method for the mesoscopic modeling of complex fluids, such as colloidal suspensions or multiphase flows. In this method, however, the underlying Cartesian grid defining the coarse-grained interaction volumes induces anisotropy. We propose an isotropic, lattice-free variant of stochastic rotation dynamics, termed iSRD. Instead of Cartesian grid cells, we employ randomly distributed spherical interaction volumes. This eliminates the requirement of a grid shift, which is essential in standard SRD to maintain Galilean invariance. We derive analytical expressions for the viscosity and the diffusion coefficient in relation to the model parameters, which show excellent agreement with the results obtained in iSRD simulations. The proposed algorithm is particularly suitable to model systems bound by walls of complex shape, where the domain cannot be meshed uniformly. The presented approach is not limited to SRD but is applicable to any other mesoscopic method, where particles interact within certain coarse-grained volumes.
6. The Rotation of Europa
Science.gov (United States)
Henrard, Jacques
2005-01-01
We present a semi-analytical theory of the rotation of Europa the Galilean satellite of Jupiter. The theory is semi-analytical in the sense that it is based on a synthetic theory of the orbit of Europa developed by Lainey. The theory is developed in the framework of Hamiltonian mechanics, using Andoyer variables and assumes that Europa is a rigid body. We consider this theory as a first step toward the modelization of a non rigid Europa covered by an ocean.
Science.gov (United States)
Pate, Brooks
2014-06-01
The past decade has seen several major technology advances in electronics operating at microwave frequencies making it possible to develop a new generation of spectrometers for molecular rotational spectroscopy. High-speed digital electronics, both arbitrary waveform generators and digitizers, continue on a Moore's Law-like development cycle that started around 1993 with device bandwidth doubling about every 36 months. These enabling technologies were the key to designing chirped-pulse Fourier transform microwave (CP-FTMW) spectrometers which offer significant sensitivity enhancements for broadband spectrum acquisition in molecular rotational spectroscopy. A special feature of the chirped-pulse spectrometer design is that it is easily implemented at low frequency (below 8 GHz) where Balle-Flygare type spectrometers with Fabry-Perot cavity designs become technologically challenging due to the mirror size requirements. The capabilities of CP-FTMW spectrometers for studies of molecular structure will be illustrated by the collaborative research effort we have been a part of to determine the structures of water clusters - a project which has identified clusters up to the pentadecamer. A second technology trend that impacts molecular rotational spectroscopy is the development of high power, solid state sources in the mm-wave/THz regions. Results from the field of mm-wave chirped-pulse Fourier transform spectroscopy will be described with an emphasis on new problems in chemical dynamics and analytical chemistry that these methods can tackle. The third (and potentially most important) technological trend is the reduction of microwave components to chip level using monolithic microwave integrated circuits (MMIC) - a technology driven by an enormous mass market in communications. Some recent advances in rotational spectrometer designs that incorporate low-cost components will be highlighted. The challenge to the high-resolution spectroscopy community - as posed by Frank De
8. Method for Design Rotation
Science.gov (United States)
1993-08-01
central composite design and give the orthogonal matrix that yields the rotation, but they do not discuss how the orthogonal matrix was found. Doehlert ... Doehlert and Klee (1972) was to start with a known orthogonal matrix of simple form and then augment the matrix with additional rows and columns to get a...larger region, a symmetric treatment of the factors, or both. 114. SUBJECT TERMS 15. NUMBER OF PAGES Orthogonal matrix Response surface design 27
9. Bioreactor rotating wall vessel
Science.gov (United States)
2001-01-01
The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells.
10. Stimulation of Rotator Cuff Repair by Sustained Release of Bone Morphogenetic Protein-7 Using a Gelatin Hydrogel Sheet.
Science.gov (United States)
Kabuto, Yukichi; Morihara, Toru; Sukenari, Tsuyoshi; Kida, Yoshikazu; Oda, Ryo; Arai, Yuji; Sawada, Koshiro; Matsuda, Ken-Ichi; Kawata, Mitsuhiro; Tabata, Yasuhiko; Fujiwara, Hiroyoshi; Kubo, Toshikazu
2015-07-01
Bone morphogenetic protein-7 (BMP-7) promotes not only osteogenesis but also matrix production in chondrocytes and tenocytes. However, because of its short half-life, maintaining local concentrations of BMP-7 is difficult. We examined the use of a gelatin hydrogel sheet (GHS) for the sustained release of BMP-7 in stimulating rotator cuff repair at the tendon-to-bone insertion. Twelve-week-old male Sprague-Dawley rats were used. Radiolabeled BMP-7 ((125)I-BMP-7) was injected into the subacromial bursa in the (125)I-BMP-7 group, whereas a GHS impregnated with (125)I-BMP-7 was implanted on the tendon attached to the tendon-to-bone insertion in the (125)I-BMP-7+GHS group. Levels of (125)I-BMP-7 in the tendon-to-bone insertion were assessed at 1, 3, 7, 14, and 21 postoperative days. The BMP-7 concentrations were significantly higher in the (125)I-BMP-7+GHS group than in the (125)I-BMP-7 group. Next, the bilateral supraspinatus tendons were resected and sutured to the greater tuberosity of the humerus using the Mason-Allen technique. Treatment groups were created as follows: either phosphate-buffered saline (PBS) or BMP-7 was injected into the subacromial bursa in the PBS and BMP-7 groups, whereas a GHS impregnated with either PBS or BMP-7 was implanted on the repaired tendon attached to the tendon-to-bone insertion in the PBS+GHS and BMP-7+GHS groups. The resected specimens were stained at 2, 4, and 8 postoperative weeks with hematoxylin and eosin as well as Safranin O, and tissue repair was evaluated histologically by using the tendon-to-bone maturing score. Tissue repair was assessed biomechanically at 4 and 8 postoperative weeks. The BMP-7+GHS group at 8 postoperative weeks demonstrated a favorable cartilage matrix production and tendon orientation; moreover, the tendon-to-bone maturing score and the ultimate force-to-failure were the highest in this group. The ability of GHS to provide controlled release of various growth factors has been previously reported. We
11. Three-mode orthomax rotation
NARCIS (Netherlands)
Kiers, Henk A.L.
1997-01-01
Factor analysis and principal components analysis (PCA) are often followed by an orthomax rotation to rotate a loading matrix to simple structure. The simple structure is usually defined in terms of the simplicity of the columns of the loading matrix. In Three-made PCA, rotational freedom of the so
12. [Influence of Operative and Conservative Therapy on the Ability to Work of Patients With Subacromial Impingement: A Prospective Clinical Comparative Study].
Science.gov (United States)
Schulze, Christoph; Köhler, Hans Christian; Kaltenborn, Alexander; Gutcke, André; Tischer, Thomas
2017-08-01
Background Subacromial impingement is a common reason for pain in the shoulder. Treatment is difficult and patients are not able to work for a long time. An increasing number of operative treatments can be observed although conservative treatment is effective, too. There is no study that observed how operative and conservative treatment influence ability to work. Methods 86 persons were included in this prospective study. Surgery was performed with an arthroscopy of the shoulder. Conservative treatment was carried out by a physiotherapist under control of the physician. Reevaluation was conducted 3 and 6 months after the initial contact. Here we observed the time the participant was not able to work, Constant Score and pain on the numeric rating scale. Results Both therapies were able to improve pain and function. During conservative treatment, improvement was faster than under operative care. Time without ability to work was 7 ± 5 weeks longer after operative treatment than under conservative therapy (p Bursitis subacromialis detected in the MRI was a predictor of faster recovery. Conclusion Conservative and operative treatment improved pain and function significantly. Properly carried out conservative therapy enables patients to get back to work earlier. Georg Thieme Verlag KG Stuttgart · New York.
13. Acute pulmonary embolism after arthroscopic glenoid labral repair and subacromial decompression: case report and review of the literature.
Science.gov (United States)
Yagnatovsky, Michelle; Dai, Amos Z; Zacchilli, Michael; Jazrawi, Laith M
2018-02-01
This report describes the case of a 29 year-old female with a history of polycystic ovary syndrome (PCOS) and on combined oral contraceptives who presents with an acute, CT confirmed pulmonary embolus of the right lower lobe, one week following arthroscopic labral repair of the right shoulder. This patient's relevant risk factors including obesity, oral contraceptive use, PCOS, and surgical positioning are discussed. Literature surrounding venous thromboembolism (VTE) following shoulder arthroscopy is also reviewed.
14. Cushing syndrome
Science.gov (United States)
Hypercortisolism; Cortisol excess; Glucocorticoid excess - Cushing syndrome ... The most common cause of Cushing syndrome is taking too much ... called exogenous Cushing syndrome . Prednisone, dexamethasone, ...
15. CISM Course on Rotating Fluids
CERN Document Server
1992-01-01
The volume presents a comprehensive overview of rotation effects on fluid behavior, emphasizing non-linear processes. The subject is introduced by giving a range of examples of rotating fluids encountered in geophysics and engineering. This is then followed by a discussion of the relevant scales and parameters of rotating flow, and an introduction to geostrophic balance and vorticity concepts. There are few books on rotating fluids and this volume is, therefore, a welcome addition. It is the first volume which contains a unified view of turbulence in rotating fluids, instability and vortex dynamics. Some aspects of wave motions covered here are not found elsewhere.
16. On general Earth's rotation theory
Science.gov (United States)
Brumberg, V.; Ivanova, T.
2009-09-01
This paper dealing with the general problem of the rigid-body rotation of the three-axial Earth represents a straightforward extension of (Brumberg and Ivanova, 2007) where the simplified Poisson equations of rotation of the axially symmetrical Earth have been considered. The aim of the present paper is to reduce the equations of the translatory motion of the major planets and the Moon and the equations of the Earth's rotation around its centre of mass to the secular system describing the evolution of the planetary and lunar orbits (independent of the Earth's rotation) and the evolution of the Earth's rotation (depending on the planetary and lunar evolution).
17. The Floating-Harbor syndrome.
Science.gov (United States)
Majewski, F; Lenard, H G
1991-02-01
We describe the seventh patient with the Floating-Harbor syndrome. Similar to previous cases in the literature this girl presented with proportionate intrauterine and postnatal growth retardation, normocephaly, triangular face with bulbous nose, long eyelashes, short upper lip, small vermilion border of upper lip, dorsally rotated ears, deep nuchal hair line, hirsutism, and clinodactyly of little fingers. She exhibited mental retardation and retarded speech development. Clinical symptoms and differential diagnosis of this rare syndrome are briefly discussed.
18. Optical fiber rotation sensing
CERN Document Server
Burns, William K; Kelley, Paul
1993-01-01
Optical Fiber Rotation Sensing is the first book devoted to Interferometric Fiber Optic Gyros (IFOG). This book provides a complete overview of IFOGs, beginning with a historical review of IFOG development and including a fundamental exposition of basic principles, a discussion of devices and components, and concluding with industry reports on state-of-the-art activity. With several chapters contributed by principal developers of this solid-state device, the result is an authoritative work which will serve as the resource for researchers, students, and users of IFOGs.* * State-of-t
19. Rotating electrical machines
CERN Document Server
Le Doeuff, René
2013-01-01
In this book a general matrix-based approach to modeling electrical machines is promulgated. The model uses instantaneous quantities for key variables and enables the user to easily take into account associations between rotating machines and static converters (such as in variable speed drives). General equations of electromechanical energy conversion are established early in the treatment of the topic and then applied to synchronous, induction and DC machines. The primary characteristics of these machines are established for steady state behavior as well as for variable speed scenarios. I
20. ROTATING PLASMA DEVICE
Science.gov (United States)
Boyer, K.; Hammel, J.E.; Longmire, C.L.; Nagle, D.E.; Ribe, F.L.; Tuck, J.L.
1961-10-24
ABS>A method and device are described for obtaining fusion reactions. The basic concept is that of using crossed electric and magnetic fields to induce a plasma rotation in which the ionized particles follow a circumferential drift orbit on wldch a cyclotron mode of motion is superimposed, the net result being a cycloidal motion about the axis of symmetry. The discharge tube has a radial electric field and a longitudinal magnetic field. Mirror machine geometry is utilized. The device avoids reliance on the pinch effect and its associated instability problems. (AEC)
1. Duane Syndrome
Science.gov (United States)
... Frequently Asked Questions Español Condiciones Chinese Conditions Duane Syndrome En Español Read in Chinese What is Duane Syndrome? Duane syndrome, also called Duane retraction syndrome (DRS), ...
2. Fanconi syndrome
Science.gov (United States)
De Toni-Fanconi syndrome ... Fanconi syndrome can be caused by faulty genes, or it may result later in life due to kidney damage. Sometimes the cause of Fanconi syndrome is unknown. Common causes of Fanconi syndrome in ...
3. Milwaukee shoulder syndrome
OpenAIRE
Somashekar SA
2014-01-01
Milwaukee shoulder syndrome or rapid destructive arthritis of the shoulder is a very rare rheumatological condition characterized by the deposition of hydroxyapatite crystals. The figure 1 shows the shoulder image of a 67-year-old female with a history of bilateral shoulder pain and swelling since 2 years and knee pain since 6 months. Physical examination revealed restriction in shoulder movements. No neurological deficit was reported. X-ray of the right shoulder indicated rotator cuff disrup...
4. Milwaukee shoulder syndrome.
Science.gov (United States)
Dewachter, L; Aerts, P; Crevits, I; De Man, R
2012-01-01
Milwaukee shoulder syndrome or rapid destructive arthropathy of the shoulder is a rare form of arthropathy that mainly affects elderly women. It is characterized by a rapid destruction of the glenohumeral joint and the rotator cuff and by an important noninflammatory joint effusion containing hydroxyapatite crystals. Radiography plays an important role in the evaluation of patients with articular disease. However, magnetic resonance imaging is the method of choice for assessing the full extent of osseous, chondral, and soft-tissue involvement.
5. Tratamiento del hombro doloroso en un servicio de rehabilitación y medicina física : estudio sobre los efectos de las ondas de choque y los ultrasonidos en el tratamiento del síndrome subacromial.
OpenAIRE
Fernández Fernández, Juan Reyes
2013-01-01
Objetivos del estudio: establecer los efectos de ultrasonidos y ondas de choque radiales en el síndrome subacromial, determinar la posible influencia del sexo y analizar la rentabilidad de ambas técnicas. Realizamos un estudio en veinticuatro pacientes repartidos en dos grupos: un grupo recibió ondas de choque y el otro ultrasonidos. Los pacientes fueron evaluados mediante la escala DASH, Constant&Murley, UCLA, SF-36 y EVA, antes del tratamiento, al mes, a los tres meses y a los seis...
6. Rotating Wheel Wake
Science.gov (United States)
Lombard, Jean-Eloi; Xu, Hui; Moxey, Dave; Sherwin, Spencer
2016-11-01
For open wheel race-cars, such as Formula One, or IndyCar, the wheels are responsible for 40 % of the total drag. For road cars, drag associated to the wheels and under-carriage can represent 20 - 60 % of total drag at highway cruise speeds. Experimental observations have reported two, three or more pairs of counter rotating vortices, the relative strength of which still remains an open question. The near wake of an unsteady rotating wheel. The numerical investigation by means of direct numerical simulation at ReD =400-1000 is presented here to further the understanding of bifurcations the flow undergoes as the Reynolds number is increased. Direct numerical simulation is performed using Nektar++, the results of which are compared to those of Pirozzoli et al. (2012). Both proper orthogonal decomposition and dynamic mode decomposition, as well as spectral analysis are leveraged to gain unprecedented insight into the bifurcations and subsequent topological differences of the wake as the Reynolds number is increased.
7. Rotational Spectrum of Saccharine
Science.gov (United States)
Alonso, Elena R.; Mata, Santiago; Alonso, José L.
2017-06-01
A significant step forward in the structure-activity relationships of sweeteners was the assignment of the AH-B moiety in sweeteners by Shallenberger and Acree. They proposed that all sweeteners contain an AH-B moiety, known as glucophore, in which A and B are electronegative atoms separated by a distance between 2.5 to 4 Å. H is a hydrogen atom attached to one of the electronegative atom by a covalent bond. For saccharine, one of the oldest artificial sweeteners widely used in food and drinks, two possible B moieties exist ,the carbonyl oxygen atom and the sulfoxide oxygen atom although there is a consensus of opinion among scientists over the assignment of AH-B moieties to HN-SO. In the present work, the solid of saccharine (m.p. 220°C) has been vaporized by laser ablation (LA) and its rotational spectrum has been analyzed by broadband CP-FTMW and narrowband MB-FTMW Fourier transform microwave techniques. The detailed structural information extracted from the rotational constants and ^{14}N nuclear quadrupole coupling constants provided enough information to ascribe the glucophore's AH and B sites of saccharine. R. S. Shallenberger, T. E. Acree. Nature 216, 480-482 Nov 1967. R. S. Shallenberger. Taste Chemistry; Blackie Academic & Professional, London, (1993).
8. Pure Nano-Rotation Scanner
Directory of Open Access Journals (Sweden)
Moo-Yeon Lee
2012-01-01
Full Text Available We developed and tested a novel rotation scanner for nano resolution and accurate rotary motion about the rotation center. The scanner consists of circular hinges and leaf springs so that the parasitic error at the center of the scanner in the X and Y directions is minimized, and rotation performance is optimized. Each sector of the scanner's system was devised to have nano resolution by minimizing the parasitic errors of the rotation center that arise due to displacements other than rotation. The analytic optimal design results of the proposed scanner were verified using finite element analyses. The piezoelectric actuators were used to attain nano-resolution performances, and a capacitive sensor was used to measure displacement. A feedback controller was used to minimize the rotation errors in the rotation scanner system under practical conditions. Finally, the performance evaluation test results showed that the resonance frequency was 542 Hz, the resolution was 0.09 μrad, and the rotation displacement was 497.2 μrad. Our test results revealed that the rotation scanner exhibited accurate rotation about the center of the scanner and had good nano precision.
9. Hamartomatous polyposis syndromes
DEFF Research Database (Denmark)
Jelsig, Anne Marie; Qvist, Niels; Brusgaard, Klaus
2014-01-01
Hamartomatous Polyposis Syndromes (HPS) are genetic syndromes, which include Peutz-Jeghers syndrome, Juvenile polyposis syndrome, PTEN hamartoma tumour syndrome (Cowden Syndrom, Bannayan-Riley-Ruvalcaba and Proteus Syndrome) as well as hereditary mixed polyposis syndrome. Other syndromes such as ...
10. Wormholes immersed in rotating matter
Directory of Open Access Journals (Sweden)
Christian Hoffmann
2018-03-01
Full Text Available We demonstrate that rotating matter sets the throat of an Ellis wormhole into rotation, allowing for wormholes which possess full reflection symmetry with respect to the two asymptotically flat spacetime regions. We analyze the properties of this new type of rotating wormholes and show that the wormhole geometry can change from a single throat to a double throat configuration. We further discuss the ergoregions and the lightring structure of these wormholes.
11. Isovector rotational model
Energy Technology Data Exchange (ETDEWEB)
Nojarov, R. (Inst. fuer Theoretische Physik, Univ. Tuebingen (Germany))
1994-04-18
The explicit form of the canonical angle operator is found and the isovector rotor is quantized in canonical relative variables ensuring the exact separation of the spurious mode. The main characteristics of the resulting joint mode, together with the low- and high-frequency parts of the split mode are obtained. It is found that the isovector rotational mode exhausts all the non-spurious M1 strength at low and high energy, providing a strong support for the interpretation of all the orbital 1[sup +] excitations as a scissors mode. Self-consistent residual interactions do not change the non-spurious restoring force of the deformed potential. Simple numerical estimates, derived from a schematic deformed oscillator, are in a good qualitative agreement with microscopic RPA results. Relationships with the results of the two-rotor model and the microscopic realization of the scissors state are established. (orig.)
12. Earth's variable rotation
Science.gov (United States)
Hide, Raymond; Dickey, Jean O.
1991-01-01
Recent improvements in geodetic data and practical meteorology have advanced research on fluctuations in the earth's rotation. The interpretation of these fluctuations is inextricably linked with studies of the dynamics of the earth-moon system and dynamical processes in the liquid metallic core of the earth (where the geomagnetic field originates), other parts of the earth's interior, and the hydrosphere and atmosphere. Fluctuations in the length of the day occurring on decadal time scales have implications for the topographay of the core-mantle boundary and the electrical, magnetic, ande other properties of the core and lower mantle. Investigations of more rapid fluctuations bear on meteorological studies of interannual, seasonal, and intraseasonal variations in the general circulation of the atmosphere and the response of the oceans to such variations.
13. Asteroid Ida Rotation Sequence
Science.gov (United States)
1994-01-01
This montage of 14 images (the time order is right to left, bottom to top) shows Ida as it appeared in the field of view of Galileo's camera on August 28, 1993. Asteroid Ida rotates once every 4 hours, 39 minutes and clockwise when viewed from above the north pole; these images cover about one Ida 'day.' This sequence has been used to create a 3-D model that shows Ida to be almost croissant shaped. The earliest view (lower right) was taken from a range of 240,000 kilometers (150,000 miles), 5.4 hours before closest approach. The asteroid Ida draws its name from mythology, in which the Greek god Zeus was raised by the nymph Ida.
14. Jacobsen syndrome.
Science.gov (United States)
Mattina, Teresa; Perrotta, Concetta Simona; Grossfeld, Paul
2009-03-07
Jacobsen syndrome is a MCA/MR contiguous gene syndrome caused by partial deletion of the long arm of chromosome 11. To date, over 200 cases have been reported. The prevalence has been estimated at 1/100,000 births, with a female/male ratio 2:1. The most common clinical features include pre- and postnatal physical growth retardation, psychomotor retardation, and characteristic facial dysmorphism (skull deformities, hypertelorism, ptosis, coloboma, downslanting palpebral fissures, epicanthal folds, broad nasal bridge, short nose, v-shaped mouth, small ears, low set posteriorly rotated ears). Abnormal platelet function, thrombocytopenia or pancytopenia are usually present at birth. Patients commonly have malformations of the heart, kidney, gastrointestinal tract, genitalia, central nervous system and skeleton. Ocular, hearing, immunological and hormonal problems may be also present. The deletion size ranges from approximately 7 to 20 Mb, with the proximal breakpoint within or telomeric to subband 11q23.3 and the deletion extending usually to the telomere. The deletion is de novo in 85% of reported cases, and in 15% of cases it results from an unbalanced segregation of a familial balanced translocation or from other chromosome rearrangements. In a minority of cases the breakpoint is at the FRA11B fragile site. Diagnosis is based on clinical findings (intellectual deficit, facial dysmorphic features and thrombocytopenia) and confirmed by cytogenetics analysis. Differential diagnoses include Turner and Noonan syndromes, and acquired thrombocytopenia due to sepsis. Prenatal diagnosis of 11q deletion is possible by amniocentesis or chorionic villus sampling and cytogenetic analysis. Management is multi-disciplinary and requires evaluation by general pediatrician, pediatric cardiologist, neurologist, ophthalmologist. Auditory tests, blood tests, endocrine and immunological assessment and follow-up should be offered to all patients. Cardiac malformations can be very severe
15. Jacobsen syndrome
Directory of Open Access Journals (Sweden)
Grossfeld Paul
2009-03-01
Full Text Available Abstract Jacobsen syndrome is a MCA/MR contiguous gene syndrome caused by partial deletion of the long arm of chromosome 11. To date, over 200 cases have been reported. The prevalence has been estimated at 1/100,000 births, with a female/male ratio 2:1. The most common clinical features include pre- and postnatal physical growth retardation, psychomotor retardation, and characteristic facial dysmorphism (skull deformities, hypertelorism, ptosis, coloboma, downslanting palpebral fissures, epicanthal folds, broad nasal bridge, short nose, v-shaped mouth, small ears, low set posteriorly rotated ears. Abnormal platelet function, thrombocytopenia or pancytopenia are usually present at birth. Patients commonly have malformations of the heart, kidney, gastrointestinal tract, genitalia, central nervous system and skeleton. Ocular, hearing, immunological and hormonal problems may be also present. The deletion size ranges from ~7 to 20 Mb, with the proximal breakpoint within or telomeric to subband 11q23.3 and the deletion extending usually to the telomere. The deletion is de novo in 85% of reported cases, and in 15% of cases it results from an unbalanced segregation of a familial balanced translocation or from other chromosome rearrangements. In a minority of cases the breakpoint is at the FRA11B fragile site. Diagnosis is based on clinical findings (intellectual deficit, facial dysmorphic features and thrombocytopenia and confirmed by cytogenetics analysis. Differential diagnoses include Turner and Noonan syndromes, and acquired thrombocytopenia due to sepsis. Prenatal diagnosis of 11q deletion is possible by amniocentesis or chorionic villus sampling and cytogenetic analysis. Management is multi-disciplinary and requires evaluation by general pediatrician, pediatric cardiologist, neurologist, ophthalmologist. Auditory tests, blood tests, endocrine and immunological assessment and follow-up should be offered to all patients. Cardiac malformations can be
16. Prediction of post-operative pain following arthroscopic subacromial decompression surgery: an observational study [v1; ref status: indexed, http://f1000r.es/9s
Directory of Open Access Journals (Sweden)
Anthony Davis
2013-02-01
Full Text Available Background: Arthroscopic shoulder surgery is increasingly performed as a day case procedure. Optimal post-operative pain relief remains a challenge due to considerable variations in the level of pain experienced between individuals. Our aim was to examine whether the preoperative electrical pain threshold was a strong predictor of elevated postoperative pain levels following arthroscopic subacromial decompression (ASD surgery. Methods: Forty consenting patients with American Society of Anesthesiologists (ASA grade 1-2 presenting for elective ASD surgery were recruited. Patients’ electrical pain thresholds were measured preoperatively using a PainMatcher® (Cefar Medical AB, Lund, Sweden device. Following surgery under general anaesthesia, the maximum pain experienced at rest and movement was recorded using a visual analogue scale until the end of postoperative day four. Results: In univariate analyses (t-test, the postoperative pain experienced (Area Under Curve was significantly greater in patients with a low pain threshold as compared with a high pain threshold at both rest (mean 12.5, S.E. 1.7 v mean 6.5, S.E.1.2. P=0.008 and on movement (mean 18.7, S.E. 1.5 v mean 14.1, S.E.1.4. P=0.031. In multivariate analyses, adjusting for additional extra analgesia, the pain experienced postoperatively was significantly greater in the low pain threshold group both at rest (mean difference 4.9, 95% CI 1.5 to 8.4, P=0.007 and on movement (mean difference 4.1, 95%CI 0.03 to 8.2, P=0.049. Conclusions: Preoperative pain threshold can predict postoperative pain level following ASD of the shoulder. Trial registration: Clinicaltrials.gov identifier: NCT01351363 Level of Evidence: II
17. Rotations, quaternions, and double groups
CERN Document Server
Altmann, Simon L
2005-01-01
This self-contained text presents a consistent description of the geometric and quaternionic treatment of rotation operators, employing methods that lead to a rigorous formulation and offering complete solutions to many illustrative problems.Geared toward upper-level undergraduates and graduate students, the book begins with chapters covering the fundamentals of symmetries, matrices, and groups, and it presents a primer on rotations and rotation matrices. Subsequent chapters explore rotations and angular momentum, tensor bases, the bilinear transformation, projective representations, and the g
18. Surface dimpling on rotating work piece using rotation cutting tool
Science.gov (United States)
Bhapkar, Rohit Arun; Larsen, Eric Richard
2015-03-31
A combined method of machining and applying a surface texture to a work piece and a tool assembly that is capable of machining and applying a surface texture to a work piece are disclosed. The disclosed method includes machining portions of an outer or inner surface of a work piece. The method also includes rotating the work piece in front of a rotating cutting tool and engaging the outer surface of the work piece with the rotating cutting tool to cut dimples in the outer surface of the work piece. The disclosed tool assembly includes a rotating cutting tool coupled to an end of a rotational machining device, such as a lathe. The same tool assembly can be used to both machine the work piece and apply a surface texture to the work piece without unloading the work piece from the tool assembly.
19. Rotational energy surfaces of molecules exhibiting internal rotation
Science.gov (United States)
Ortigoso, Juan; Hougen, Jon T.
1994-08-01
Rotational energy surfaces [W. G. Harter and C. W. Patterson, J. Chem. Phys. 80, 4241 (1984)] for a molecule with internal rotation are constructed. The study is limited to torsional states at or below the top of the barrier to internal rotation, where the extra (torsional) degree of freedom can be eliminated by expanding eigenvalues of the torsion-K-rotation Hamiltonian as a Fourier series in the rotational degree of freedom. For acetaldehyde, considered as an example, this corresponds to considering vt=0, 1, and 2 (below the barrier) and vt=3 (just above the barrier). The rotational energy surfaces are characterized by locating their stationary points (maxima, minima, and saddles) and separatrices. Rather complicated catastrophe histories describing the creation and annihilation of pairs of stationary points as a function of J are found at moderate J for given torsional quantum number (vt) and symmetry species (A,E). Trajectories on the rotational energy surface which quantize the action are examined, and changes from rotational to vibrational trajectories caused by changes in the separatrix structure are found as a function of J for vt=2. The concept of a best'' quantization axis for the molecule-fixed component of the total angular momentum is examined from a classical point of view, and it is shown that labeling ambiguities encountered in the literature for torsion-rotation energy levels, calculated numerically in the rho-axis system, can be eliminated by reprojecting basis-set K values onto an axis passing through an appropriate stationary point on the rotational energy surface.
20. High-Current Rotating Contactor
Science.gov (United States)
Hagan, David W.; Wolff, Edwin D.
1996-01-01
Rotating electrical contactor capable of carrying 1,000 amperes of current built for use in rotating large workpiece in electroplating bath. Electrical contact made by use of 24 automotive starter motor brushes adapted to match inside diameter of shell electrode.
1. Rotation of the planet mercury.
Science.gov (United States)
Jefferys, W H
1966-04-08
The equations of motion for the rotation of Mercury are solved for the general case by an asymptotic expansion. The findings of Liu and O'Keefe, obtained by numerical integration of a special case, that it is possible for Mercury's rotation to be locked into a 2:3 resonance with its revolution, are confirmed in detail. The general solution has further applications.
2. KEPLER RAPIDLY ROTATING GIANT STARS
Energy Technology Data Exchange (ETDEWEB)
Costa, A. D.; Martins, B. L. Canto; Bravo, J. P.; Paz-Chinchón, F.; Chagas, M. L. das; Leão, I. C.; Oliveira, G. Pereira de; Silva, R. Rodrigues da; Roque, S.; Oliveira, L. L. A. de; Silva, D. Freire da; De Medeiros, J. R., E-mail: renan@dfte.ufrn.br [Departamento de Física Teórica e Experimental, Universidade Federal do Rio Grande do Norte, Campus Universitário, Natal RN (Brazil)
2015-07-10
Rapidly rotating giant stars are relatively rare and may represent important stages of stellar evolution, resulting from stellar coalescence of close binary systems or accretion of substellar companions by their hosting stars. In the present Letter, we report 17 giant stars observed in the scope of the Kepler space mission exhibiting rapid rotation behavior. For the first time, the abnormal rotational behavior for this puzzling family of stars is revealed by direct measurements of rotation, namely from photometric rotation period, exhibiting a very short rotation period with values ranging from 13 to 55 days. This finding points to remarkable surface rotation rates, up to 18 times the rotation of the Sun. These giants are combined with six others recently listed in the literature for mid-infrared (IR) diagnostics based on Wide-field Infrared Survey Explorer information, from which a trend for an IR excess is revealed for at least one-half of the stars, but at a level far lower than the dust excess emission shown by planet-bearing main-sequence stars.
3. Noonan syndrome
Directory of Open Access Journals (Sweden)
van der Burgt Ineke
2007-01-01
Full Text Available Abstract Noonan Syndrome (NS is characterised by short stature, typical facial dysmorphology and congenital heart defects. The incidence of NS is estimated to be between 1:1000 and 1:2500 live births. The main facial features of NS are hypertelorism with down-slanting palpebral fissures, ptosis and low-set posteriorly rotated ears with a thickened helix. The cardiovascular defects most commonly associated with this condition are pulmonary stenosis and hypertrophic cardiomyopathy. Other associated features are webbed neck, chest deformity, mild intellectual deficit, cryptorchidism, poor feeding in infancy, bleeding tendency and lymphatic dysplasias. The syndrome is transmitted as an autosomal dominant trait. In approximately 50% of cases, the disease is caused by missense mutations in the PTPN11 gene on chromosome 12, resulting in a gain of function of the non-receptor protein tyrosine phosphatase SHP-2 protein. Recently, mutations in the KRAS gene have been identified in a small proportion of patients with NS. A DNA test for mutation analysis can be carried out on blood, chorionic villi and amniotic fluid samples. NS should be considered in all foetuses with polyhydramnion, pleural effusions, oedema and increased nuchal fluid with a normal karyotype. With special care and counselling, the majority of children with NS will grow up and function normally in the adult world. Management should address feeding problems in early childhood, evaluation of cardiac function and assessment of growth and motor development. Physiotherapy and/or speech therapy should be offered if indicated. A complete eye examination and hearing evaluation should be performed during the first few years of schooling. Preoperative coagulation studies are indicated. Signs and symptoms lessen with age and most adults with NS do not require special medical care.
4. Advances in Rotational Seismic Measurements
Energy Technology Data Exchange (ETDEWEB)
Pierson, Robert [Applied Technology Associates, Albuquerque, NM (United States); Laughlin, Darren [Applied Technology Associates, Albuquerque, NM (United States); Brune, Robert [Applied Technology Associates, Albuquerque, NM (United States)
2016-10-19
Rotational motion is increasingly understood to be a significant part of seismic wave motion. Rotations can be important in earthquake strong motion and in Induced Seismicity Monitoring. Rotational seismic data can also enable shear selectivity and improve wavefield sampling for vertical geophones in 3D surveys, among other applications. However, sensor technology has been a limiting factor to date. The US Department of Energy (DOE) and Applied Technology Associates (ATA) are funding a multi-year project that is now entering Phase 2 to develop and deploy a new generation of rotational sensors for validation of rotational seismic applications. Initial focus is on induced seismicity monitoring, particularly for Enhanced Geothermal Systems (EGS) with fracturing. The sensors employ Magnetohydrodynamic (MHD) principles with broadband response, improved noise floors, robustness, and repeatability. This paper presents a summary of Phase 1 results and Phase 2 status.
5. Bidirectional optical rotation of cells
Directory of Open Access Journals (Sweden)
Jiyi Wu
2017-08-01
Full Text Available Precise and controlled rotation manipulation of cells is extremely important in biological applications and biomedical studies. Particularly, bidirectional rotation manipulation of a single or multiple cells is a challenge for cell tomography and analysis. In this paper, we report an optical method that is capable of bidirectional rotation manipulation of a single or multiple cells. By launching a laser beam at 980 nm into dual-beam tapered fibers, a single or multiple cells in solutions can be trapped and rotated bidirectionally under the action of optical forces. Moreover, the rotational behavior can be controlled by altering the relative distance between the two fibers and the input optical power. Experimental results were interpreted by numerical simulations.
6. Rotational superradiance in fluid laboratories
CERN Document Server
Cardoso, Vitor; Richartz, Mauricio; Weinfurtner, Silke
2016-01-01
Rotational superradiance has been predicted theoretically decades ago, and is the chief responsible for a number of important effects and phenomenology in black hole physics. However, rotational superradiance has never been observed experimentally. Here, with the aim of probing superradiance in the lab, we investigate the behaviour of sound and surface waves in fluids resting in a circular basin at the center of which a rotating cylinder is placed. We show that with a suitable choice for the material of the cylinder, surface and sound waves are amplified. By confining the superradiant modes near the rotating cylinder, an instability sets in. Our findings are experimentally testable in existing fluid laboratories and hence offer experimental exploration and comparison of dynamical instabilities arising from rapidly rotating boundary layers in astrophysical as well as in fluid dynamical systems.
7. Rotation periods and photometric variability of rapidly rotating ultracool dwarfs
Science.gov (United States)
Miles-Páez, P. A.; Pallé, E.; Zapatero Osorio, M. R.
2017-12-01
We used the optical and near-infrared imagers located on the Liverpool, the IAC80, and the William Herschel telescopes to monitor 18 M7-L9.5 dwarfs with the objective of measuring their rotation periods. We achieved accuracies typically in the range ±1.5-28 mmag by means of differential photometry, which allowed us to detect photometric variability at the 2σ level in the 50 per cent of the sample. We also detected periodic modulation with periods in the interval 1.5-4.4 h in 9 out of 18 dwarfs that we attribute to rotation. Our variability detections were combined with data from the literature; we found that 65 ± 18 per cent of M7-L3.5 dwarfs with v sin I ≥ 30 km s-1 exhibit photometric variability with typical amplitudes ≤20 mmag in the I band. For those targets and field ultracool dwarfs with measurements of v sin I and rotation period we derived the expected inclination angle of their rotation axis, and found that those with v sin I ≥ 30 km s-1 are more likely to have inclinations ≳40 deg. In addition, we used these rotation periods and others from the literature to study the likely relationship between rotation and linear polarization in dusty ultracool dwarfs. We found a correlation between short rotation periods and large values of linear polarization at optical and near-infrared wavelengths.
Science.gov (United States)
Smarandache, Florentin
2012-10-01
Two twins settle on a massive spherical planet at a train station S. Let's consider that each twin has an accompanying clock, and the two clocks are synchronized. One twin T1 remains in the train station, while the other twin T2 travels at a uniform high speed with the train around the planet (on the big circle of the planet) until he gets back to the same train station S. Assume the planet is not rotating. Since the planet is massive, we can consider that on a very small part on its surface the train rail road is linear, so the train is in a linear uniform motion. The larger is the planet's radius the more the rail road approaches a linear trajectory. Because the GPS clocks are alleged to be built on the Theory of Relativity, one can consider the twin T2 train's circular trajectory alike the satellite's orbit. In addition, the gravitation is the same for the reference frames of T1 and T2. Each twin sees the other twin as traveling, therefore each twin finds the other one has aged slower than him. Thus herein we have a relativistic symmetry. When T2 returns to train station S, he finds out that he is younger than T1 (therefore asymmetry). Thus, one gets a contradiction between symmetry and asymmetry.
9. Treatments for shoulder impingement syndrome: a PRISMA systematic review and network meta-analysis.
Science.gov (United States)
Dong, Wei; Goost, Hans; Lin, Xiang-Bo; Burger, Christof; Paul, Christian; Wang, Zeng-Li; Zhang, Tian-Yi; Jiang, Zhi-Chao; Welle, Kristian; Kabir, Koroush
2015-03-01
Many treatments for shoulder impingement syndrome (SIS) are available in clinical practice; some of which have already been compared with other treatments by various investigators. However, a comprehensive treatment comparison is lacking. Several widely used electronic databases were searched for eligible studies. The outcome measurements were the pain score and the Constant-Murley score (CMS). Direct comparisons were performed using the conventional pair-wise meta-analysis method, while a network meta-analysis based on the Bayesian model was used to calculate the results of all potentially possible comparisons and rank probabilities. Included in the meta-analysis procedure were 33 randomized controlled trials involving 2300 patients. Good agreement was demonstrated between the results of the pair-wise meta-analyses and the network meta-analyses. Regarding nonoperative treatments, with respect to the pain score, combined treatments composed of exercise and other therapies tended to yield better effects than single-intervention therapies. Localized drug injections that were combined with exercise showed better treatment effects than any other treatments, whereas worse effects were observed when such injections were used alone. Regarding the CMS, most combined treatments based on exercise also demonstrated better effects than exercise alone. Regarding surgical treatments, according to the pain score and the CMS, arthroscopic subacromial decompression (ASD) together with treatments derived from it, such as ASD combined with radiofrequency and arthroscopic bursectomy, showed better effects than open subacromial decompression (OSD) and OSD combined with the injection of platelet-leukocyte gel. Exercise therapy also demonstrated good performance. Results for inconsistency, sensitivity analysis, and meta-regression all supported the robustness and reliability of these network meta-analyses. Exercise and other exercise-based therapies, such as kinesio taping, specific
10. Williams syndrome
Science.gov (United States)
A support group can be helpful for emotional support and for giving and receiving practical advice. The following organization provides additional information about Williams Syndrome: Williams Syndrome Association -- www.williams-syndrome.org
11. WIEDEMANN SYNDROME
African Journals Online (AJOL)
hi-tech
BILATERAL BENIGN HAEMORRHAGIC ADRENAL CYSTS IN BECKWITH - WIEDEMANN. SYNDROME: CASE REPORT. P. ANOOP and M. A. ANJAY. SUMMARY. Beckwith-Wiedemann syndrome is the most common overgrowth malformation syndrome. The classical features include macrosomia, macroglossia, ...
12. Marfan Syndrome
Science.gov (United States)
Marfan syndrome is a disorder that affects connective tissue. Connective tissues are proteins that support skin, bones, blood vessels, ... A problem with the fibrillin gene causes Marfan syndrome. Marfan syndrome can be mild to severe, and ...
13. Brown Syndrome
Science.gov (United States)
... extraction) have also been linked to acquired Brown syndrome. Inflammation of the tendon-trochlea complex (from adult and juvenile rheumatoid arthritis, systemic lupus erythematosus and sinusitis) can be ... syndrome hereditary? Hereditary cases of Brown syndrome are rare. ...
14. Asperger Syndrome
Science.gov (United States)
... Page You are here Home » Disorders » All Disorders Asperger Syndrome Information Page Asperger Syndrome Information Page What research is being done? ... Definition Treatment Prognosis Clinical Trials Organizations Publications Definition Asperger syndrome (AS) is a developmental disorder. It is ...
15. Surgical repair and rehabilitation of a combined 330° capsulolabral lesion and partial-thickness rotator cuff tear in a professional quarterback: a case report.
Science.gov (United States)
Wilk, Kevin E; Macrina, Lonard C; Yenchak, Adrian J; Cain, E Lyle; Andrews, James R
2013-03-01
Case report. Traumatic glenohumeral dislocations with concomitant rotator cuff and capsular injuries present a unique and challenging surgical and rehabilitative condition, particularly in the overhead-throwing athlete. Multiple injuries of the shoulder complex create the potential for complications in the course of recovery and place a full return to high-level sport at risk. The purpose of this case report is to present the multiphased rehabilitation approach of an elite professional quarterback after an acute 330° capsulolabral reconstruction and rotator cuff repair as a result of a luxatio erecta injury. A 26-year-old male professional football player, a quarterback, sustained a right luxatio erecta shoulder dislocation while trying to recover a fumble during a regular-season game. The injury occurred when he was hit in the back of his throwing shoulder, which was in an abducted and externally rotated position, while lying on the ground. Five days postinjury, he underwent a 330° capsulolabral repair, with concomitant rotator cuff repair and subacromial decompression. He completed 28 weeks of a multiphased rehabilitation program. The patient returned to play in the National Football League (NFL) 8 months later, for the start of the next season, during which he had his most productive year as a professional quarterback, leading the league in passing yards and finishing third in the league for the number of touchdowns. Since the injury, the patient has played 6 consecutive seasons, starting over 96 consecutive, regular-season games and maintaining a very high level of play. This case report highlights the clinical decision-making process and management of this rare, severe injury.
16. Conservative treatment preferences and the plausible mechanism of Neer's stage 1 of shoulder impingement in younger people.
Science.gov (United States)
2015-05-01
The interaction of various factors in the vicious cycle (VC) of subacromial impingement syndrome (SIS) is complex and there are conservative treatment preferences for speedy rehabilitation. The mechanism of SIS is not fully understood and the inappropriate treatment priorities cause delay in rehabilitation. SIS is related to the reduction in the subacromial space (SS). Posterior capsular tightness (PCT) and rotator cuff (RC) dysfunction are the two basic mechanisms in this regard. PCT may cause anterosuperior translation of humeral head (HH) and anterior acromion tipping through scapular dyskinesis, thereby reducing the subacromial space. Alteration in the force couple of muscle secondary to scapular dyskinesis eventually causes injury to subacromial structures. The rotator cuff is important in centring the humeral head in the glenoid cavity and superior translation of humeral head occurs if their function is compromised. Posterior capsular tightness may affect the function of rotator cuff action which leads to early fatigue, dysfunction of these muscles and eventually impingement. Adhesive changes take place in various structures around the shoulder secondary to impingement pain and relative immobility, which further aggravates the problem. To reverse the vicious cycle, conservative intervention should therefore be directed to loosen posterior capsular tightness, restore rotator cuff function through appropriate exercise in a pain-free range through appropriate exercise, mobilisation of adhesion through teraservers friction or pain-free mobilisation or grade I and grade II manipulation. Depending on the level of irritability, pain control intervention could be considered alongside.
17. Canonical elements of rotational motion
Science.gov (United States)
Fukushima, T.
2009-09-01
We present a new set of canonical variables to describe general rotation of a triaxial rigid body. Explicit are both the forward and backward transformations from the new variables to the Andoyer canonical variables, which are universal. The rotational kinetic energy is expressed as a quadratic monomial of one new momentum. Consequently, the torque-free rotations are expressed as a linear function of time for the conjugate coordinate and constants of time for the rest two coordinates and three momenta. This means that the new canonical variables are universal elements in a broad sense.
18. Optical wheel-rotation sensor
Energy Technology Data Exchange (ETDEWEB)
Veeser, L.; Rodriguez, P.; Forman, P. [Los Alamos National Lab., NM (United States); Deeter, M. [National Inst. of Standards and Technology, Boulder, CO (United States)
1994-05-01
We describe a fiber-optic rotation sensor based on diffraction of light in a magneto-optic crystal (BIG). Exploitation of this effect permits the construction of a sensor requiring no polarization elements or lenses.
19. Spontaneous Rotational Inversion in Phycomyces
KAUST Repository
Goriely, Alain
2011-03-01
The filamentary fungus Phycomyces blakesleeanus undergoes a series of remarkable transitions during aerial growth. During what is known as the stagea IV growth phase, the fungus extends while rotating in a counterclockwise manner when viewed from above (stagea IVa) and then, while continuing to grow, spontaneously reverses to a clockwise rotation (stagea IVb). This phase lasts for 24-48Ah and is sometimes followed by yet another reversal (stageAIVc) before the overall growth ends. Here, we propose a continuum mechanical model of this entire process using nonlinear, anisotropic, elasticity and show how helical anisotropy associated with the cell wall structure can induce spontaneous rotation and, under appropriate circumstances, the observed reversal of rotational handedness. © 2011 American Physical Society.
20. DOWN SYNDROME WITH MOYAMOYA SYNDROME
National Research Council Canada - National Science Library
Mohan Makwana; R. K. Vishnoi; Jai Prakash Soni; Kapil Jetha; Suresh Kumar Verma; Pradeep Singh Rathore; Monika Choudhary
2017-01-01
...,” in which the arterial changes are seen among patients with various syndromes or other disease processes- Down syndrome, sickle cell anaemia, neurofibromatosis type-1, congenital heart disease...
1. Muscle shortening manoeuvre reduces pain and functional impairment in shoulder impingement syndrome: clinical and ultrasonographic evidence.
Science.gov (United States)
Melchiorre, Daniela; Maresca, Marco; Bracci, Riccardo; Ravaschio, Andrea; Valiensi, Bruno; Casale, Roberto; Bandinelli, Francesca; Candelieri, Antonio; Maddali Bongi, Susanna; Porta, Francesco; Innocenti, Massimo; Carulli, Christian; Matucci Cerinic, Marco
2014-01-01
To evaluate the short-term efficacy of muscle shortening manoeuvre (MSM), by inducing an increase in strength of the shoulder muscles, for the treatment of shoulder impingement syndrome (SIS). Sixty subjects (mean age: 58.6 years) with SIS were assigned to one of 3 different treatment interventions: 1) MSM: a series of fast accelerations in the upward direction was applied to the upper limb that was also submitted to forces acting in the opposite direction (added mass); 2) traditional physiotherapeutic technique: scapulothoracic gliding; 3) simple traction: the added mass was applied to the limb without the series of fast accelerations. Pain intensity, Neer's impingement sign, range of motion and muscle strength were assessed. Ultrasound (US) examination was performed before, immediately after and 30 days after each treatment to study the width of the subacromial-subdeltoid bursa, long biceps tendon sheath and acromioclavicular joint. Impingement was evaluated by dynamic examination. After treatment with MSM, pain was significantly reduced (p<0.001), Neer's impingement sign was negative, range of motion and muscle strength were increased. US examination showed that the widths of the subacromial-subdeltoid bursa (p<0.001), long biceps tendon sheath (p<0.001) and acromioclavicular joint (p<0.001) were significantly reduced; impingement was no more detected. After 30 days, improvement in clinical and US findings was maintained. In the two control groups, no significant changes were observed after treatment. Clinical and US findings demonstrate that MSM, by inducing an increase in muscle strength, is effective in the short-term treatment of SIS.
2. [Biomechanic results in impingement syndrome of the shoulder].
Science.gov (United States)
Wuelker, N; Plitz, W; Roetman, B; Rössig, S
1995-01-01
Forces underneath the coraco-acromial vault during elevation of the arm were evaluated with a dynamic shoulder model. The deltoid muscle and the rotator cuff muscles were simulated with a hydrodynamic device, in ten autopsy specimens. Controlled cycles of glenohumeral joint motion were initiated with computerised regulation. An ultrasonic device measured the position of the arm in all spatial orientations. Capacitive sensors recorded forces underneath the coraco-acromial vault. The mean force during one cycle of elevation averaged 13.9 Newton +/- 12.5 Newton underneath the coraco-acromial ligament and 3.44 Newton +/- 4.37 Newton underneath the coracoid process. The peak force averaged 37.8 Newton +/- 33.2 Newton underneath the acromion, 3.03 Newton +/- 2.62 Newton underneath the coraco-acromial ligament and 6.93 Newton +/- 7.38 Newton underneath the coracoid process. The force markedly increased at the final stage of arm elevation and during early reverse-elevation in most specimens, corresponding to the painful arc sign. In some specimens, the force under the coracoid process exceeded the force under the acromion. Osteophytes protruding into the subacromial space may lead to a concentration of force and to high regional pressures.
3. Kindler syndrome
Directory of Open Access Journals (Sweden)
Kaviarasan P
2005-01-01
Full Text Available Kindler syndrome is a rare autosomal recessive disorder associated with skin fragility. It is characterized by blistering in infancy, photosensitivity and progressive poikiloderma. The syndrome involves the skin and mucous membrane with radiological changes. The genetic defect has been identified on the short arm of chromosome 20. This report describes an 18-year-old patient with classical features like blistering and photosensitivity in childhood and the subsequent development of poikiloderma. The differential diagnosis of Kindler syndrome includes diseases like Bloom syndrome, Cockayne syndrome, dyskeratosis congenita, epidermolysis bullosa, Rothmund-Thomson syndrome and xeroderma pigmentosum. Our patient had classical cutaneous features of Kindler syndrome with phimosis as a complication.
4. Full can test: Mechanisms of a positive test in patients with shoulder pain.
Science.gov (United States)
Timmons, Mark K; Yesilyaprak, Sevgi S; Ericksen, Jeff; Michener, Lori A
2017-02-01
The full can test is theorized to produce compressive loads on the supraspinatus tendon within the subacromial space. Characterizing the width of the subacromial outlet, scapular orientation, and shoulder pain during the full can test will improve the mechanistic understanding of the positive full can test. Cross-sectional repeated measures design. Participants with subacromial pain syndrome (n=30) were compared to a matched control group (n=30) during 2 conditions: passive support, and the full can test. The full can test was performed with the arm elevated to 90° in the scapular plane. In both conditions, measurements were taken of acromiohumeral distance with ultrasonography, scapular position using electromagnetic tracking, shoulder strength using a dynamometer, and shoulder pain with the 11-point rating scale. During the full can test, both groups had a decreased acromial humeral distance, scapular upward rotation, posterior tilt, external rotation and clavicular protraction as compared to passive support (ppain group as compared to the control group reported greater shoulder pain (ppain and reduced strength in those with subacromial pain syndrome can be explained additionally by an increase in scapular anterior tilt. These mechanistic changes may lead to tendon compression, but this cannot be verified as direct tendon compression was not measured. Copyright © 2016 Elsevier Ltd. All rights reserved.
5. Spline screw multiple rotations mechanism
Science.gov (United States)
Vranish, John M. (Inventor)
1993-01-01
A system for coupling two bodies together and for transmitting torque from one body to another with mechanical timing and sequencing is reported. The mechanical timing and sequencing is handled so that the following criteria are met: (1) the bodies are handled in a safe manner and nothing floats loose in space, (2) electrical connectors are engaged as long as possible so that the internal processes can be monitored throughout by sensors, and (3) electrical and mechanical power and signals are coupled. The first body has a splined driver for providing the input torque. The second body has a threaded drive member capable of rotation and limited translation. The embedded drive member will mate with and fasten to the splined driver. The second body has an embedded bevel gear member capable of rotation and limited translation. This bevel gear member is coaxial with the threaded drive member. A compression spring provides a preload on the rotating threaded member, and a thrust bearing is used for limiting the translation of the bevel gear member so that when the bevel gear member reaches the upward limit of its translation the two bodies are fully coupled and the bevel gear member then rotates due to the input torque transmitted from the splined driver through the threaded drive member to the bevel gear member. An output bevel gear with an attached output drive shaft is embedded in the second body and meshes with the threaded rotating bevel gear member to transmit the input torque to the output drive shaft.
6. Critical rotation of general-relativistic polytropic models revisited
Science.gov (United States)
Geroyannis, V.; Karageorgopoulos, V.
2013-09-01
We develop a perturbation method for computing the critical rotational parameter as a function of the equatorial radius of a rigidly rotating polytropic model in the "post-Newtonia approximation" (PNA). We treat our models as "initial value problems" (IVP) of ordinary differential equations in the complex plane. The computations are carried out by the code dcrkf54.f95 (Geroyannis and Valvi 2012 [P1]; modified Runge-Kutta-Fehlberg code of fourth and fifth order for solving initial value problems in the complex plane). Such a complex-plane treatment removes the syndromes appearing in this particular family of IVPs (see e.g. P1, Sec. 3) and allows continuation of the numerical integrations beyond the surface of the star. Thus all the required values of the Lane-Emden function(s) in the post-Newtonian approximation are calculated by interpolation (so avoiding any extrapolation). An interesting point is that, in our computations, we take into account the complete correction due to the gravitational term, and this issue is a remarkable difference compared to the classical PNA. We solve the generalized density as a function of the equatorial radius and find the critical rotational parameter. Our computations are extended to certain other physical characteristics (like mass, angular momentum, rotational kinetic energy, etc). We find that our method yields results comparable with those of other reliable methods. REFERENCE: V.S. Geroyannis and F.N. Valvi 2012, International Journal of Modern Physics C, 23, No 5, 1250038:1-15.
7. Rotational Modes in Phononic Crystals
Science.gov (United States)
Wu, Ying; Peng, Pai; Mei, Jun
2014-03-01
We propose a lumped model for the rotational modes in two-dimensional phononic crystals comprised of square arrays of solid cylindrical scatterers in solid hosts. The model not only can reproduce the dispersion relations in a certain range with one fitted parameter, but also gives simple analytical expressions for the frequencies of the eigenmodes at the high symmetry points in the Brillouin zone. These expressions provide physical understandings of the rotational modes as well as certain translational and hybrid mode, and predict the presence of accidental degeneracy of the rotational and dipolar modes, which leads to a Dirac-like cone in the Brillouin zone center. Supported by KAUST Baseline Research Fund, National Natural Science Foundation of China (Grants No. 10804086 and No. 11274120), and the Fundamental Research Funds for the Central Universities (Grant No. 2012ZZ0077).
8. Instabilities in coaxial rotating jets
Science.gov (United States)
Ivanic, Tanja; Foucault, Eric; Pecheux, Jean; Gilard, Virginie
2000-12-01
The aim of this study is the characterization of the cylindrical mixing layer resulting from the interaction of two coaxial swirling jets. The experimental part of this study was performed in a cylindrical water tunnel, permitting an independent rotation of two coaxial jets. The rotations are generated by means of 2×36 blades localized in two swirling chambers. As expected, the evolution of the main instability modes presents certain differences compared to the plane-mixing-layer case. Experimental results obtained by tomography showed the existence of vortex rings and streamwise vortex pairs in the near field region. This method also permitted the observation of the evolution and interaction of different modes. PIV velocity measurements realized in the meridian plans and the plans perpendicular to the jet axis show that rotation distorts the typical top-hat axial velocity profile. The transition of the axial velocity profile from jet-like into wake-like is also observed.
9. The ability of preoperative factors to predict patient-reported disability following surgery for rotator cuff pathology.
Science.gov (United States)
Woollard, Jason D; Bost, James E; Piva, Sara R; Kelley Fitzgerald, G; Rodosky, Mark W; Irrgang, James J
2017-10-01
Minimal research has examined the prognostic ability of shoulder examination data or psychosocial factors in predicting patient-reported disability following surgery for rotator cuff pathology. The purpose of this study was to examine these factors for prognostic value in order to help clinicians and patients understand preoperative factors that impact disability following surgery. Sixty-two patients scheduled for subacromial decompression with or without supraspinatus repair were recruited. Six-month follow-up data were available for 46 patients. Patient characteristics, history of the condition, shoulder impairments, psychosocial factors, and patient-reported disability questionnaires were collected preoperatively. Six months following surgery, the Western Ontario Rotator Cuff Index (WORC) and global rating of change dichotomized subjects into responders versus nonresponders. Logistic regression quantified prognostic ability and created the most parsimonious model to predict outcome. Being on modified job duty (OR = .17, 95%CI: 0.03-0.94), and having a worker's compensation claim (OR = 0.08, 95%CI: 0.01-0.74) decreased probability of a positive outcome, while surgery on the dominant shoulder (OR = 11.96, 95%CI: 2.91-49.18) increased probability. From the examination, only impaired internal rotation strength was a significant univariate predictor. The Fear-avoidance Beliefs Questionnaire (FABQ) score (OR = 0.95, 95%CI: 0.91-0.98) and the FABQ_work subscale (OR = 0.92, 95%CI: 0.87-0.97) were univariate predictors. In the final model, surgery on the dominant shoulder (OR = 8.9, 95%CI 1.75-45.7) and FABQ_work subscale score ≤25 (OR = 15.3, 95%CI 2.3-101.9) remained significant. Surgery on the dominant arm resulted in greater improvement in patient-reported disability, thereby increasing the odds of a successful surgery. The predictive ability of the FABQ_work subscale highlights the potential impact of psychosocial factors on patient
10. Coracoid impingement syndrome due to intensive rock climbing training.
Science.gov (United States)
Schöffl, Volker; Schneider, Hans; Küpper, Thomas
2011-06-01
Overuse and acute injuries to the upper body are common in rock climbing. Such injuries primarily affect the fingers; but shoulder problems are increasingly common, especially among more experienced and older climbers who climb at a high ability level. Such shoulder problems are often due to subacromial impingement, shoulder dislocations with bankart lesions, hyperlaxity, SLAP lesions or irritations of the long biceps tendon. In contrast to these known conditions, we describe a case of an ambitious female rock climber who trained intensively and developed a coracoid impingement caused by hypertrophied subscapularis tendon and muscle following sport-specific training. Diagnosis was made through clinical evaluation and confirmed by magnetic resonance tomography. Coracoid impingement syndrome is a less common cause of shoulder pain and occurs when the subscapularis tendon impinges between the coracoid and the lesser tuberosity of the humerus. The patient was treated successfully with a conservative therapy and returned to full activity within 6 weeks. Copyright © 2011 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.
11. Astrogeodynamic Studies of Earth Rotation
Science.gov (United States)
Pacheco, A.; Alonso, E.; Podesta, R.; Actis, E.
2006-06-01
From OAFA's Photoelectric Astrolabe Pa II systematic observations of stellar fundamental groups on period 1992 - 2002 we have determined (UT0-UTC) Time Variation Curve corresponding to Earth Rotation and its comparison with data (UT1-UTC) given by International Earth Rotation Service (IERS) We have obtained values of the curve from the average of observations of each night with their respective weights, and have corrected them by Pole Movement. We have also studied the possibility of relations between anomalies on Time Variation (UT0-UTC) and important earthquakes happened on the neighborhood of the Astrolabe.
12. Rotationally actuated prosthetic helping hand
Science.gov (United States)
Norton, William E. (Inventor); Belcher, Jewell G., Jr. (Inventor); Carden, James R. (Inventor); West, Thomas W. (Inventor)
1991-01-01
A prosthetic device has been developed for below-the-elbow amputees. The device consists of a cuff, a stem, a housing, two hook-like fingers, an elastic band for holding the fingers together, and a brace. The fingers are pivotally mounted on a housing that is secured to the amputee's upper arm with the brace. The stem, which also contains a cam, is rotationally mounted within the housing and is secured to the cuff, which fits over the amputee's stump. By rotating the cammed stem between the fingers with the lower arm, the amputee can open and close the fingers.
13. Mercury's rotation axis and period
Science.gov (United States)
Klaasen, K. P.
1976-01-01
Recent measurements made from high-resolution Mariner 10 photography of the planet Mercury yield a rotation period of 58.6461 + or 0.005 days, in excellent agreement with the period required for a precise 2/3 resonance with its orbital period (58.6462 days). The axis of rotation of the planet was calculated to be offset about 2 deg from the perpendicular to its orbital plane within a 50% probability error ellipse of + or - 2.6 deg by + or - 6.5 deg. Dynamical considerations make it most likely that the true displacement from the orbit normal is less than 1 deg.
14. Relativity on Rotated Graph Paper
CERN Document Server
2011-01-01
We present visual calculations in special relativity using spacetime diagrams drawn on graph paper that has been rotated by 45 degrees. The rotated lines represent lightlike directions in Minkowski spacetime, and the boxes in the grid (called "light-clock diamonds") represent units of measurement modeled on the ticks of an inertial observer's lightclock. We show that many quantitative results can be read off a spacetime diagram by counting boxes, using a minimal amount of algebra. We use the Doppler Effect, in the spirit of the Bondi k-calculus, to motivate the method.
15. Strongly interacting matter under rotation
Directory of Open Access Journals (Sweden)
Jiang Yin
2018-01-01
Full Text Available The vorticity-driven effects are systematically studied in various aspects. With AMPT the distributions of vorticity has been investigated in heavy ion collisions with different collision parameters. Taking the rotational polarization effect into account a generic condensate suppression mechanism is discussed and quantitatively studied with NJL model. And in chiral restored phase the chiral vortical effects would generate a new collective mode, i.e. the chiral vortical wave. Using the rotating quark-gluon plasma in heavy ion collisions as a concrete example, we show the formation of induced flavor quadrupole in QGP and estimate the elliptic flow splitting effect for Λ baryons.
16. ENGINEERING BULLETIN: ROTATING BIOLOGICAL CONTACTORS
Science.gov (United States)
Rotating biological contactors employ aerobic fixed-film treatment to degrade either organic and/or nitrogenous (ammonia-nitrogen) constituents present in aqueous waste streams. ixed-film systems provide a surface to which the biomass can adhere. Treatment is achieved as the wast...
17. Rotational alignment in soft nuclei
Energy Technology Data Exchange (ETDEWEB)
1983-12-08
It is shown that in transitional odd-A nuclei, where the rotation-aligned coupling scheme usually takes place, the low collective angular momentum states of the decoupled band are not completely aligned due to core softness. This is illustrated on the example of La-nuclei.
18. Rotational dynamics with geometric algebra
Science.gov (United States)
Hestenes, D.
1983-01-01
A new spinor formulation of rotational dynamics is developed. A general theorem is established reducing the theory of the symmetric top to that of the spherical top. The classical problems of Lagrange and Poinsot are treated in detail, along with a modern application to the theory of magnetic resonance.
19. Rotational diffusion in dense suspensions
NARCIS (Netherlands)
Hagen, M. H. J.; Frenkel, D.; Lowe, C.P.
1999-01-01
We have computed the rotational diffusion coefficient for a suspension of hard spheres. We find excellent agreement with experimental results over a density range up to, and including, the colloidal crystal. However, we find that theories derived to second order in the volume fraction overestimate
20. Rotating black hole and quintessence
CERN Document Server
Ghosh, Sushant G
2015-01-01
We discuss spherically symmetric exact solutions of the Einstein equations for quintessential matter surrounding a black hole (BH), which has additional parameters ($\\alpha$ and $\\omega$) due to the quintessential matter, apart from the mass ($M$). In turn, we employ the Newman\$$-\$$Janis complex transformation to this spherical quintessence BH solution and present a rotating counterpart that is identified, for \$\\alpha=-e^2 \
NARCIS (Netherlands)
Heald, George
2015-01-01
Synchrotron radiation and its degree of linear polarization are powerful tracers of magnetic fields that are illuminated by cosmic ray electrons. Faraday rotation of the linearly polarized radiation is induced by intervening line-of-sight magnetic fields that are embedded in ionized plasmas. For
2. Dumping Syndrome
Science.gov (United States)
... Intestinal Pseudo-obstruction Irritable Bowel Syndrome (IBS) Definition & Facts Symptoms & Causes Diagnosis Treatment Eating, Diet, & Nutrition Clinical Trials Irritable Bowel Syndrome (IBS) in Children Lactose Intolerance Ménétrier’s Disease Microscopic Colitis Ostomy Surgery of the ...
3. Piriformis syndrome
Science.gov (United States)
Pseudosciatica; Wallet sciatica; Hip socket neuropathy; Pelvic outlet syndrome; Low back pain - piriformis ... Sciatica is the main symptom of piriformis syndrome. Other symptoms include: Tenderness or a dull ache in ...
4. Alagille Syndrome
Science.gov (United States)
... Liver Tumors Biliary Atresia Cirrhosis of the Liver Galactosemia Gilbert’s Syndrome Diseases of the Liver Glycogen Storage ... Liver Tumors Biliary Atresia Cirrhosis of the Liver Galactosemia Gilbert’s Syndrome Diseases of the Liver Glycogen Storage ...
5. Reye Syndrome
Science.gov (United States)
... Liver Tumors Biliary Atresia Cirrhosis of the Liver Galactosemia Gilbert’s Syndrome Diseases of the Liver Glycogen Storage ... Liver Tumors Biliary Atresia Cirrhosis of the Liver Galactosemia Gilbert’s Syndrome Diseases of the Liver Glycogen Storage ...
6. Zellweger Syndrome
Science.gov (United States)
... Zellweger syndrome (ZS, the most severe form), neonatal adrenoleukodystrophy (NALD), and Infantile Refsum disease (IRD, the least ... Zellweger syndrome (ZS, the most severe form), neonatal adrenoleukodystrophy (NALD), and Infantile Refsum disease (IRD, the least ...
7. Proteus syndrome
Directory of Open Access Journals (Sweden)
Criton S
1995-01-01
Full Text Available Proteus syndrome is a hamartomatous disorder characterised by focal overgrowths that can involve any structure of the body. An eleven-year-old girl with Proteus syndrome has been described with clitoromegaly.
8. Overlap syndromes
NARCIS (Netherlands)
Beuers, Ulrich; Rust, Christian
2005-01-01
In hepatology, the term overlap syndrome describes variant forms of the major hepatobiliary autoimmune diseases, autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), and primary sclerosing cholangitis (PSC). Patients with overlap syndromes present with both hepatitic and cholestatic
9. Metabolic Syndrome
Science.gov (United States)
Metabolic syndrome is a group of conditions that put you at risk for heart disease and diabetes. These ... doctors agree on the definition or cause of metabolic syndrome. The cause might be insulin resistance. Insulin is ...
10. Reye Syndrome
Science.gov (United States)
Reye syndrome is a rare illness that can affect the blood, liver, and brain of someone who has recently ... a viral illness, seek medical attention immediately. Reye syndrome can lead to a coma and brain death, ...
11. Usher Syndrome
Science.gov (United States)
Usher syndrome is an inherited disease that causes serious hearing loss and retinitis pigmentosa, an eye disorder that causes ... and vision. There are three types of Usher syndrome: People with type I are deaf from birth ...
12. Turner Syndrome
Science.gov (United States)
Turner syndrome is a genetic disorder that affects a girl's development. The cause is a missing or incomplete X ... work properly. Other physical features typical of Turner syndrome are Short, "webbed" neck with folds of skin ...
13. Felty syndrome
Science.gov (United States)
Seropositive rheumatoid arthritis (RA); Felty's syndrome ... The cause of Felty syndrome is unknown. It is more common in people who have had rheumatoid arthritis (RA) for a long time. People with ...
14. Rett Syndrome
Science.gov (United States)
Rett syndrome is a rare genetic disease that causes developmental and nervous system problems, mostly in girls. It's related to autism spectrum disorder. Babies with Rett syndrome seem to grow and develop normally at first. ...
15. Alport Syndrome
Science.gov (United States)
... body. Many people with Alport syndrome also have hearing problems and abnormalities with their eyes. Other signs and ... and inherited type of Alport syndrome. For example, hearing and vision problems tend to be more common in males than ...
16. Moebius Syndrome
Science.gov (United States)
... eye sensitivity; motor delays; high or cleft palate; hearing problems and speech difficulties. Children with Moebius syndrome are ... eye sensitivity; motor delays; high or cleft palate; hearing problems and speech difficulties. Children with Moebius syndrome are ...
17. Heart and Down Syndrome
Science.gov (United States)
... 4602 [email protected] Down Syndrome What Is Down Syndrome? Down Syndrome Facts Myths & Truths Preferred Language Guide Q& ... Helpline » Follow us Down Syndrome What Is Down Syndrome? Down Syndrome Facts Myths & Truths Preferred Language Guide Q& ...
18. Down Syndrome: Education
Science.gov (United States)
... 4602 [email protected] Down Syndrome What Is Down Syndrome? Down Syndrome Facts Myths & Truths Preferred Language Guide Q& ... Helpline » Follow us Down Syndrome What Is Down Syndrome? Down Syndrome Facts Myths & Truths Preferred Language Guide Q& ...
19. Dental Issues & Down Syndrome
Science.gov (United States)
... 4602 [email protected] Down Syndrome What Is Down Syndrome? Down Syndrome Facts Myths & Truths Preferred Language Guide Q& ... Helpline » Follow us Down Syndrome What Is Down Syndrome? Down Syndrome Facts Myths & Truths Preferred Language Guide Q& ...
20. Down Syndrome: Education
Science.gov (United States)
... Our Team Financial Information NDSS History About Down Syndrome Down Syndrome Preferred Language Guide Down Syndrome Facts Down ... Our Team Financial Information NDSS History About Down Syndrome Down Syndrome Down Syndrome Facts Preferred Language Guide Publications ... | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.36559364199638367, "perplexity": 14038.94642879304}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-17/segments/1524125948285.62/warc/CC-MAIN-20180426144615-20180426164615-00629.warc.gz"} |
https://trac.sagemath.org/ticket/21328?cversion=1&cnum_hist=11 | Opened 6 years ago
Closed 5 years ago
# Create a new class for Parity-Check Codes
Reported by: Owned by: richmond major sage-7.6 coding theory linear code, sd75, rd3 dlucas, nthiery Tania Richmond David Lucas, Julien Lavauzelle N/A 1aa4b4e 1aa4b4e7333d96fc39836bee509fee97cfe28dfc
A linear parity-check code of length n and dimension k over GF(q), with n = k+1 is the set of all words, formed by the checksum at the last position of all k first symbols modulo q.
This ticket proposes a new class for parity-check codes along with an encoder for it.
### comment:1 Changed 6 years ago by richmond
• Branch set to u/richmond/parity_codes
### comment:2 Changed 6 years ago by richmond
• Commit set to b77de0ff1050b206b78e8b127f8dce32c0ff6c68
Hello,
I implemented a new class for parity-check codes over GF(q), with generator matrix (identity matrix concatenated with a ones column) and straightforward (minus sum of message symbols added at the end of the message) encoder classes. I also implemented a method for minimum distance.
Setting to needs-review.
Tania.
New commits:
52b8b8a adds relative_distance method b77de0f Added new file that introduces the new parity-check code class. Initializes code class, generator matrix encoder class, straightforward encoder class and minimum distance method.
### comment:3 Changed 6 years ago by richmond
• Authors set to Tania Richmond
• Description modified (diff)
• Status changed from new to needs_review
• Summary changed from Create a new class for Parity Codes to Create a new class for Parity-Check Codes
### comment:4 follow-ups: ↓ 5 ↓ 11 Changed 6 years ago by dlucas
Hi Tania,
• You forgot to add your module (Python file) to the index of documented modules for sage/coding, which means no html/pdf documentation file will be generated for parity_check_code.py. You have to add sage/coding/parity_check_code to sage/doc/en/reference/coding/index.rst.
• Once done, you'll notice building the documentation fails because there's already a reference named [W] in /sage/schemes/hyperelliptic_curves/invariants.py. So, you have to rename your [W] to something else ([W88]?)
• I would add a small definition of a parity-check code in the module docstring (where you wrote "A simple way of detecting [...] even."). What about:
" A parity-check code of dimension k over F_q is the set:
\{(m_1, \dots, m_k, -\Sigma_{i=1}^{k}) m_i \mid (m_1, \dots, m_n) \in F_q\}"?
## ParityCheckCode
• __init__: I think you forgot to remove the docstring. Here it does not make a lot of sense to write "An abstract linear code object should never be created.". I usually omit
docstring for __init__ as I consider there's already some doc in the class docstring.
• __init__: I would add or no base_field.is_field() to the sanity check line 73. Indeed, for now if one passes anything but a field, the error message says AttributeError: 'anything' object has no attribute 'is_finite' which is not the most informative error message. BTW, it's also possible to create a Parity-Check code whose dimension is 0 or less. I know #21326 will fix that soon, but I guess a simple check on dimension can't hurt, right? And in any case, there should be at least something like if not isinstance(dimension, (int, Integer) raise ValueError("dimension has to be a Python int or a Sage Integer"). Otherwise, if the user passes anything but an int/Integer, it will fail with some weird error.
## ParityCheckGeneratorMatrixEncoder
• Doctest lines 179-183 calls the straightforward encoder instead of the generator matrix encoder.
sage: C = codes.RandomLinearCode(10, 4, GF(11))
sage: codes.encoders.ParityCheckCodeGeneratorMatrixEncoder(C)
works while it should fail.
• generator_matrix: I'm quite sure l.246 should be G = G.augment(vector([field.order()] * k)). Because for now, the encoding does not work:
sage: C = codes.ParityCheckCode(GF(5),7)
sage: E = codes.encoders.ParityCheckCodeGeneratorMatrixEncoder(C)
sage: m = vector(GF(5), [1, 0, 4, 2, 0, 3, 2])
sage: sum(E.encode(m))
4 #should be 0
## ParityCheckCodeStraightForwardEncoder
• I know we already talked about it, but I still think StraightforwardEncoder is not the most straightforward name... What about ParitySymbolEncoder? Note that I am not adamant with this name change though.
• encode: I think you can do it in one line with return vector(self.code().base_field(), message.list()+[-sum(message)])
## Encoders
• Last one: lines 404/405, you chose "ParityCheckGeneratorMatrixEncoder" and "ParityCheckStraightforwardEncoder" for the encoders string names. I'd choose "GeneratorMatrix" and "Straightforward" instead, as the user has to type those names when they use C.encoder('str_name'). See the names I chose in grs.py for instance.
Apart from those small remarks, it looks good. Great job for your first code class :)
David
### comment:5 in reply to: ↑ 4 ; follow-up: ↓ 6 Changed 6 years ago by nthiery
• __init__: I think you forgot to remove the docstring. Here it does not make a lot of sense to write "An abstract linear code object should never be created.". I usually omit
docstring for __init__ as I consider there's already some doc in the class docstring.
Just to clarify: __init__ methods, like all other methods, should have a docstring. But it can be made into a bare minimal, with a single doctest constructing an object and running generic tests on it; typically:
def init(self, ...):
""" Initialize this parity code
TESTS
sage: C = ParityCode?(...) sage: TestSuite?(C).run()
"""
Great job for your first code class :)
+1!
Cheers,
Nicolas
### comment:6 in reply to: ↑ 5 ; follow-up: ↓ 10 Changed 6 years ago by dlucas
• __init__: I think you forgot to remove the docstring. Here it does not make a lot of sense to write "An abstract linear code object should never be created.". I usually omit
docstring for __init__ as I consider there's already some doc in the class docstring.
Just to clarify: __init__ methods, like all other methods, should have a docstring. But it can be made into a bare minimal, with a single doctest constructing an object and running generic tests on it; typically:
def init(self, ...):
""" Initialize this parity code
TESTS
sage: C = ParityCode?(...) sage: TestSuite?(C).run()
"""
Oops. Well, I guess I should open a ticket to fix my __init__ then, because all my classes look like:
class ClassName:
r"""
Short description
Long description
EXAMPLES::
....
"""
def __init__(self, ...):
r"""
TESTS::
....
"""
BTW, doctest line 383 in parity_check_code.py should run unencode_nocheck, not unencode. sage --coverage complains about this... But not about missing docstrings in my __init__ blocks.
David
### comment:7 follow-up: ↓ 9 Changed 6 years ago by dlucas
• Reviewers set to David Lucas
Hi,
I just noticed something: according to the diff, you also implement relative_distance in this ticket. I'm quite sure it's because you were working on #21315 at the same time. Could you please remove the related lines from linear_code.py?
David
### comment:8 Changed 6 years ago by git
• Commit changed from b77de0ff1050b206b78e8b127f8dce32c0ff6c68 to 0b0d2f82b033532d2084219b1ee1d6f0c63f45e0
Branch pushed to git repo; I updated commit sha1. New commits:
0b0d2f8 Correcting mistakes. Two errors are still waiting for correction: ParityCheckCodeStraightforwardEncoder.unencode_nocheck and ParityCheckCodeGeneratorMatrixEncoder.__init__
### comment:9 in reply to: ↑ 7 Changed 6 years ago by richmond
Hi,
I just noticed something: according to the diff, you also implement relative_distance in this ticket. I'm quite sure it's because you were working on #21315 at the same time. Could you please remove the related lines from linear_code.py?
David
Hi,
True! I removed this method.
Tania.
### comment:10 in reply to: ↑ 6 Changed 6 years ago by richmond
• __init__: I think you forgot to remove the docstring. Here it does not make a lot of sense to write "An abstract linear code object should never be created.". I usually omit
docstring for __init__ as I consider there's already some doc in the class docstring.
Just to clarify: __init__ methods, like all other methods, should have a docstring. But it can be made into a bare minimal, with a single doctest constructing an object and running generic tests on it; typically:
def init(self, ...):
""" Initialize this parity code
TESTS
sage: C = ParityCode?(...) sage: TestSuite?(C).run()
"""
Oops. Well, I guess I should open a ticket to fix my __init__ then, because all my classes look like:
class ClassName:
r"""
Short description
Long description
EXAMPLES::
....
"""
def __init__(self, ...):
r"""
TESTS::
....
"""
BTW, doctest line 383 in parity_check_code.py should run unencode_nocheck, not unencode. sage --coverage complains about this... But not about missing docstrings in my __init__ blocks.
David
Hi,
I changed unencode by unencode_nocheck, but it gives me an error in tests. I do not understand exactly where does it come from, so if you can take a look on it please...
For description and test, I just followed the toturial: http://doc.sagemath.org/html/en/thematic_tutorials/structures_in_coding_theory.html I also took inspiration from others classes in coding theory (like Hamming code or GRS code). I hope it is correct like that.
Tania.
Last edited 6 years ago by richmond (previous) (diff)
### comment:11 in reply to: ↑ 4 Changed 6 years ago by richmond
Hi Tania,
• You forgot to add your module (Python file) to the index of documented modules for sage/coding, which means no html/pdf documentation file will be generated for parity_check_code.py. You have to add sage/coding/parity_check_code to sage/doc/en/reference/coding/index.rst.
• Once done, you'll notice building the documentation fails because there's already a reference named [W] in /sage/schemes/hyperelliptic_curves/invariants.py. So, you have to rename your [W] to something else ([W88]?)
• I would add a small definition of a parity-check code in the module docstring (where you wrote "A simple way of detecting [...] even."). What about:
" A parity-check code of dimension k over F_q is the set:
\{(m_1, \dots, m_k, -\Sigma_{i=1}^{k}) m_i \mid (m_1, \dots, m_n) \in F_q\}"?
## ParityCheckCode
• __init__: I think you forgot to remove the docstring. Here it does not make a lot of sense to write "An abstract linear code object should never be created.". I usually omit
docstring for __init__ as I consider there's already some doc in the class docstring.
• __init__: I would add or no base_field.is_field() to the sanity check line 73. Indeed, for now if one passes anything but a field, the error message says AttributeError: 'anything' object has no attribute 'is_finite' which is not the most informative error message. BTW, it's also possible to create a Parity-Check code whose dimension is 0 or less. I know #21326 will fix that soon, but I guess a simple check on dimension can't hurt, right? And in any case, there should be at least something like if not isinstance(dimension, (int, Integer) raise ValueError("dimension has to be a Python int or a Sage Integer"). Otherwise, if the user passes anything but an int/Integer, it will fail with some weird error.
## ParityCheckGeneratorMatrixEncoder
• Doctest lines 179-183 calls the straightforward encoder instead of the generator matrix encoder.
sage: C = codes.RandomLinearCode(10, 4, GF(11))
sage: codes.encoders.ParityCheckCodeGeneratorMatrixEncoder(C)
works while it should fail.
• generator_matrix: I'm quite sure l.246 should be G = G.augment(vector([field.order()] * k)). Because for now, the encoding does not work:
sage: C = codes.ParityCheckCode(GF(5),7)
sage: E = codes.encoders.ParityCheckCodeGeneratorMatrixEncoder(C)
sage: m = vector(GF(5), [1, 0, 4, 2, 0, 3, 2])
sage: sum(E.encode(m))
4 #should be 0
## ParityCheckCodeStraightForwardEncoder
• I know we already talked about it, but I still think StraightforwardEncoder is not the most straightforward name... What about ParitySymbolEncoder? Note that I am not adamant with this name change though.
• encode: I think you can do it in one line with return vector(self.code().base_field(), message.list()+[-sum(message)])
## Encoders
• Last one: lines 404/405, you chose "ParityCheckGeneratorMatrixEncoder" and "ParityCheckStraightforwardEncoder" for the encoders string names. I'd choose "GeneratorMatrix" and "Straightforward" instead, as the user has to type those names when they use C.encoder('str_name'). See the names I chose in grs.py for instance.
Apart from those small remarks, it looks good. Great job for your first code class :)
David
Hi,
Thank you for this long but useful comment. I made changes you asked except in ParityCheckGeneratorMatrixEncoder. Indeed, if we suppose that a word is a codeword only when the sum of all its coodinates, then G = G.augment(vector(field,[- field.one()] * k)). It was my mistake because I use to work with binary codes so there is no -.
Tania.
Last edited 6 years ago by richmond (previous) (diff)
### comment:12 Changed 6 years ago by jlavauzelle
Hi Tania,
A first general comment. When you push a new version of your code, you must take care if a new release has been done. For instance, your code is written under release 7.4.beta1, but we're now under 7.4.beta5. So you need to merge your version with the latest beta. New releases are announced here: https://groups.google.com/forum/#!forum/sage-release
• Your push seems to remove relative_distance() method in linear_code.py. Now, this method is on the latest release, so you need to keep it.
• l.9 : m_k instead of m_n
• In ParityCheckCodeGeneratorMatrixEncoder, the constructor won't raise any error as it is claimed in the doctest. Generically, you can run sage tests (./sage -t --long src/sage/coding/parity_check_code.py) to see if your doctests are well written.
• Then you'll also see that codes.RandomLinearCode(n, k, F) is deprecated. Use codes.random_linear_code(F, n, k)instead.
• l.199 to 210 : it seems that you only copy paste the _latex_ function of the code, whithout replacing the code by the encoder.
• This is the same for the _repr_ method (only the doctest).
• The two previous remarks also hold for ParityCheckCodeStraightforwardEncoder (lines 297 to 320).
• You need a unencode_nocheck() method in ParityCheckCodeStraightforwardEncoder.
Best,
Julien
### comment:13 Changed 5 years ago by jlavauzelle
• Branch changed from u/richmond/parity_codes to u/jlavauzelle/parity_codes
### comment:14 Changed 5 years ago by jlavauzelle
• Commit changed from 0b0d2f82b033532d2084219b1ee1d6f0c63f45e0 to 1aa4b4e7333d96fc39836bee509fee97cfe28dfc
• Milestone changed from sage-7.4 to sage-7.6
• Reviewers changed from David Lucas to David Lucas, Julien Lavauzelle
Hi,
I fixed what I proposed and solved the merge conflict. Maybe it still need a quick review because I did many (minor) changes.
Julien
New commits:
62abcd7 Fixed merge conflict. 1aa4b4e Fixed doctests. Shorter output. Generator matrix encoder inherits from the generic one. Fixed encoders. Cleaned the code.
### comment:15 Changed 5 years ago by dlucas
• Status changed from needs_review to positive_review
Hello,
Tests pass, doc compiles, I agree with your changes, giving the green light.
David
### comment:16 Changed 5 years ago by jsrn
• Status changed from positive_review to needs_work
Codes should no longer print in the way the current implementation here does.
### comment:17 Changed 5 years ago by jsrn
• Status changed from needs_work to positive_review
Sorry, I was being too fast. Everything is allright here.
### comment:18 Changed 5 years ago by vbraun
• Branch changed from u/jlavauzelle/parity_codes to 1aa4b4e7333d96fc39836bee509fee97cfe28dfc
• Resolution set to fixed
• Status changed from positive_review to closed
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http://dictionnaire.sensagent.leparisien.fr/Pulse-code%20modulation/en-en/ | Publicité ▼
anglais ▼ rechercher
## définition - Pulse-code modulation
voir la définition de Wikipedia
# synonymes - Pulse-code modulation signaler un problème
pulse code modulation (n.)
PCM (abbreviation)
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## dictionnaire analogique
pulse code modulation (n.)
Wikipedia
# Pulse-code modulation
Pulse-code modulation (PCM) is a method used to digitally represent sampled analog signals. It is the standard form for digital audio in computers and various Blu-ray, DVD and Compact Disc formats, as well as other uses such as digital telephone systems. A PCM stream is a digital representation of an analog signal, in which the magnitude of the analog signal is sampled regularly at uniform intervals, with each sample being quantized to the nearest value within a range of digital steps.
PCM streams have two basic properties that determine their fidelity to the original analog signal: the sampling rate, which is the number of times per second that samples are taken; and the bit depth, which determines the number of possible digital values that each sample can take.
## History
In the history of electrical communications, the earliest reason for sampling a signal was to interlace samples from multiple telegraphy sources, and convey them over a single telegraph cable. Telegraph time-division multiplexing (TDM) was conveyed as early as 1853, by the American inventor Moses G. Farmer. The electrical engineer W. M. Miner, in 1903, used an electro-mechanical commutator for time-division multiplex of multiple telegraph signals, and also applied this technology to telephony. He obtained intelligible speech from channels sampled at a rate above 3500–4300 Hz; lower rates were unsatisfactory. This was TDM, but pulse-amplitude modulation (PAM) rather than PCM.
In 1926, Paul M. Rainey of Western Electric patented a facsimile machine which transmitted its signal using 5-bit PCM, encoded by an opto-mechanical analog-to-digital converter.[1] The machine did not go into production. British engineer Alec Reeves, unaware of previous work, conceived the use of PCM for voice communication in 1937 while working for International Telephone and Telegraph in France. He described the theory and advantages, but no practical use resulted. Reeves filed for a French patent in 1938, and his U.S. patent was granted in 1943.
The first transmission of speech by digital techniques was the SIGSALY encryption equipment used for high-level Allied communications during World War II. In 1943, the Bell Labs researchers who designed the SIGSALY system became aware of the use of PCM binary coding as already proposed by Alec Reeves. In 1949 for the Canadian Navy's DATAR system, Ferranti Canada built a working PCM radio system that was able to transmit digitized radar data over long distances.[2]
PCM in the late 1940s and early 1950s used a cathode-ray coding tube with a plate electrode having encoding perforations.[3][4] As in an oscilloscope, the beam was swept horizontally at the sample rate while the vertical deflection was controlled by the input analog signal, causing the beam to pass through higher or lower portions of the perforated plate. The plate collected or passed the beam, producing current variations in binary code, one bit at a time. Rather than natural binary, the grid of Goodall's later tube was perforated to produce a glitch-free Gray code, and produced all bits simultaneously by using a fan beam instead of a scanning beam.
In the United States, the National Inventors Hall of Fame has honored Bernard M. Oliver[5] and Claude Shannon[6] as the inventors of PCM,[7] as described in 'Communication System Employing Pulse Code Modulation,' U.S. Patent 2,801,281 filed in 1946 and 1952, granted in 1956. Another patent by the same title was filed by John R. Pierce in 1945, and issued in 1948: U.S. Patent 2,437,707. The three of them published "The Philosophy of PCM" in 1948.[8]
Pulse-code modulation (PCM) was used in Japan by Denon in 1972 for the mastering and production of analogue phonograph records, using a 2-inch Quadruplex-format videotape recorder for its transport, but this was not developed into a consumer product.
## Modulation
Sampling and quantization of a signal (red) for 4-bit PCM
In the diagram, a sine wave (red curve) is sampled and quantized for pulse code modulation. The sine wave is sampled at regular intervals, shown as ticks on the x-axis. For each sample, one of the available values (ticks on the y-axis) is chosen by some algorithm. This produces a fully discrete representation of the input signal (shaded area) that can be easily encoded as digital data for storage or manipulation. For the sine wave example at right, we can verify that the quantized values at the sampling moments are 7, 9, 11, 12, 13, 14, 14, 15, 15, 15, 14, etc. Encoding these values as binary numbers would result in the following set of nibbles: 0111 (23×0+22×1+21×1+20×1=0+4+2+1=7), 1001, 1011, 1100, 1101, 1110, 1110, 1111, 1111, 1111, 1110, etc. These digital values could then be further processed or analyzed by a digital signal processor. Several PCM streams could also be multiplexed into a larger aggregate data stream, generally for transmission of multiple streams over a single physical link. One technique is called time-division multiplexing (TDM) and is widely used, notably in the modern public telephone system.
The PCM process is commonly implemented on a single integrated circuit generally referred to as an analog-to-digital converter (ADC).
## Demodulation
To recover the original signal from the sampled data, one applies the procedure of modulation in reverse. After each sampling period has passed, the demodulator reads the next value and shifts the output signal to the new value. As a result of these transitions, the signal has a significant amount of high-frequency energy. To remove these undesirable frequencies and leave the original signal, the demodulator passes the signal through analog filters that suppress energy outside the expected frequency range (that is, greater than the Nyquist frequency $f_s / 2$).[note 1] The sampling theorem suggests that practical PCM devices, provided a sampling frequency that is sufficiently greater than that of the input signal, can operate without introducing significant distortions within their designed frequency bands.
The electronics involved in producing an accurate analog signal from the discrete data are similar to those used for generating the digital signal. These devices are Digital-to-analog converters (DACs), and operate similarly to ADCs. They produce on their output a voltage or current (depending on type) that represents the value presented on their digital inputs. This output would then generally be filtered and amplified for use.
## Limitations
There are potential sources of impairment implicit in any PCM system:
• Choosing a discrete value near the analog signal for each sample leads to quantization error.[note 2]
• Between samples no measurement of the signal is made; the sampling theorem guarantees non-ambiguous representation and recovery of the signal only if it has no energy at frequency fs/2 or higher (one half the sampling frequency, known as the Nyquist frequency); higher frequencies will generally not be correctly represented or recovered.
• As samples are dependent on time, an accurate clock is required for accurate reproduction. If either the encoding or decoding clock is not stable, its frequency drift will directly affect the output quality of the device.[note 3]
## Digitization as part of the PCM process
In conventional PCM, the analog signal may be processed (e.g., by amplitude compression) before being digitized. Once the signal is digitized, the PCM signal is usually subjected to further processing (e.g., digital data compression).
PCM with linear quantization is known as Linear PCM (LPCM).[9]
Some forms of PCM combine signal processing with coding. Older versions of these systems applied the processing in the analog domain as part of the analog-to-digital process; newer implementations do so in the digital domain. These simple techniques have been largely rendered obsolete by modern transform-based audio compression techniques.
• DPCM encodes the PCM values as differences between the current and the predicted value. An algorithm predicts the next sample based on the previous samples, and the encoder stores only the difference between this prediction and the actual value. If the prediction is reasonable, fewer bits can be used to represent the same information. For audio, this type of encoding reduces the number of bits required per sample by about 25% compared to PCM.
• Adaptive DPCM (ADPCM) is a variant of DPCM that varies the size of the quantization step, to allow further reduction of the required bandwidth for a given signal-to-noise ratio.
• Delta modulation is a form of DPCM which uses one bit per sample.
In telephony, a standard audio signal for a single phone call is encoded as 8,000 analog samples per second, of 8 bits each, giving a 64 kbit/s digital signal known as DS0. The default signal compression encoding on a DS0 is either μ-law (mu-law) PCM (North America and Japan) or A-law PCM (Europe and most of the rest of the world). These are logarithmic compression systems where a 12 or 13-bit linear PCM sample number is mapped into an 8-bit value. This system is described by international standard G.711. An alternative proposal for a floating point representation, with 5-bit mantissa and 3-bit radix, was abandoned.
Where circuit costs are high and loss of voice quality is acceptable, it sometimes makes sense to compress the voice signal even further. An ADPCM algorithm is used to map a series of 8-bit µ-law or A-law PCM samples into a series of 4-bit ADPCM samples. In this way, the capacity of the line is doubled. The technique is detailed in the G.726 standard.
Later it was found that even further compression was possible and additional standards were published. Some of these international standards describe systems and ideas which are covered by privately owned patents and thus use of these standards requires payments to the patent holders.
Some ADPCM techniques are used in Voice over IP communications.
## Encoding for serial transmission
Pulse-code modulation can be either return-to-zero (RZ) or non-return-to-zero (NRZ). For a NRZ system to be synchronized using in-band information, there must not be long sequences of identical symbols, such as ones or zeroes. For binary PCM systems, the density of 1-symbols is called ones-density.[10]
Ones-density is often controlled using precoding techniques such as Run Length Limited encoding, where the PCM code is expanded into a slightly longer code with a guaranteed bound on ones-density before modulation into the channel. In other cases, extra framing bits are added into the stream which guarantee at least occasional symbol transitions.
Another technique used to control ones-density is the use of a scrambler polynomial on the raw data which will tend to turn the raw data stream into a stream that looks pseudo-random, but where the raw stream can be recovered exactly by reversing the effect of the polynomial. In this case, long runs of zeroes or ones are still possible on the output, but are considered unlikely enough to be within normal engineering tolerance.
In other cases, the long term DC value of the modulated signal is important, as building up a DC offset will tend to bias detector circuits out of their operating range. In this case special measures are taken to keep a count of the cumulative DC offset, and to modify the codes if necessary to make the DC offset always tend back to zero.
Many of these codes are bipolar codes, where the pulses can be positive, negative or absent. In the typical alternate mark inversion code, non-zero pulses alternate between being positive and negative. These rules may be violated to generate special symbols used for framing or other special purposes.
## Nomenclature
The word pulse in the term Pulse-Code Modulation refers to the "pulses" to be found in the transmission line. This perhaps is a natural consequence of this technique having evolved alongside two analog methods, pulse width modulation and pulse position modulation, in which the information to be encoded is in fact represented by discrete signal pulses of varying width or position, respectively. In this respect, PCM bears little resemblance to these other forms of signal encoding, except that all can be used in time division multiplexing, and the numbers of the PCM codes are represented as electrical pulses. The device that performs the coding and decoding function in a telephone circuit is called a codec.
## Notes
1. ^ Some systems use digital filtering to remove some of the aliasing, converting the signal from digital to analog at a higher sample rate such that the analog filter required for anti-aliasing is much simpler. In some systems, no explicit filtering is done at all; as it's impossible for any system to reproduce a signal with infinite bandwidth, inherent losses in the system compensate for the artifacts — or the system simply does not require much precision.
2. ^ Quantization error swings between -q/2 and q/2. In the ideal case (with a fully linear ADC) it is uniformly distributed over this interval, with zero mean and variance of q2/12.
3. ^ A slight difference between the encoding and decoding clock frequencies is not generally a major concern; a small constant error is not noticeable. Clock error does become a major issue if the clock is not stable, however. A drifting clock, even with a relatively small error, will cause very obvious distortions in audio and video signals, for example.
## References
1. ^ U.S. patent number 1,608,527; also see p. 8, Data conversion handbook, Walter Allan Kester, ed., Newnes, 2005, ISBN 0-7506-7841-0.
2. ^ Porter, Arthur. So Many Hills to Climb (2004) Beckham Publications Group
3. ^ R. W. Sears, "Electron Beam Deflection Tube for Pulse Code Modulation," Bell Sys. Tech. J., Vol. 27 pp. 44–57
4. ^ W. M. Goodall, "Television by Pulse Code Modulation," Bell Sys. Tech. J., Vol. 30 pp. 33–49, 1951.
5. ^ "Bernard Oliver". National Inventor's Hall of Fame. Retrieved 6 Feb. 2011.
6. ^ "Claude Shannon". National Inventor's Hall of Fame. Retrieved 6 Feb. 2011.
7. ^ "National Inventors Hall of Fame announces 2004 class of inventors". Science Blog. February 11, 2004. Retrieved 6 Feb. 2011.
8. ^ B. M. Oliver, J. R. Pierce, and C. E. Shannon (Nov. 1948). "The Philosophy of PCM". Proceeding of the IRE 36 (11): 1324–1331. DOI:10.1109/JRPROC.1948.231941. ISSN 0096-8390.
9. ^ "Linear Pulse Code Modulated Audio (LPCM)". The Library of Congress. Retrieved 2010-03-21.
10. ^ Stallings, William, Digital Signaling Techniques, December 1984, Vol. 22, No. 12, IEEE Communications Magazine
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http://tex.stackexchange.com/questions/35554/how-can-i-auto-adjust-a-equation-to-appear-in-the-entire-page-scale-to-equatio | # How can I auto adjust a equation to appear in the entire page? (Scale to equations, is this exist?)
If I have a document like this:
\documentclass[landscape, 12pt]{report}
\usepackage[landscape]{geometry}
\usepackage[utf8x]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsmath, amssymb, graphics, setspace}
\newcommand{\mathsym}[1]{{}}
\newcommand{\unicode}[1]{{}}
\newcounter{mathematicapage}
\begin{document} $$\label{Equation:Naive_Bayes_Classifier} P\left(H_h|E_1,E_2,\ldots ,E_e,\ldots E_{\mathbb{E}}\right)=\frac{P\left(H_h\right) P\left(E_1|H_h\right) P\left(E_2|H_h,E_1\right) \text{\ldots P} \left(E_e|H_h,E_1,E_2,\ldots ,E_{e-1},E_{e+1} \ldots, E_{\mathbb{E}}\right) \text{\ldots P} \left(E_{\mathbb{E}}|H_h,E_1,E_2,\ldots ,E_{\mathbb{E}-1}\right)}{ P\left(E_1,E_2,\ldots,E_e, \ldots ,E_{\mathbb{E}}\right)}$$
\end{document}
How can I auto adjust this equation to appear in the entire page, using all horizontal space? (Without badboxes or smaller than the width of the page?)
If is there a kind of scale to use in equations, giving explicity how greater the equation should become, this solver my problem too.
-
I added a }{ to get your code to work- let me know if it wasn't appropriate (or simply roll back or edit) – cmhughes Nov 21 '11 at 2:20
You may also consider adjusting the equation layout (and not merely using \frac) in order to make it fit within \textwidth. – Werner Nov 21 '11 at 4:08
Why those useless \left and \right? And \text{$\ldots$ P} doesn't make much sense. If you want an upright P it should be \mathrm{P} in all the formula. – egreg Nov 21 '11 at 14:52
The equation was generated in Mathematica, which makes a ton of warts like that. – rdhs Nov 21 '11 at 15:53
@rdhs is correct. – GarouDan Nov 21 '11 at 19:38
To "scale" an equation to fit a box you can use \resizebox from the package graphicx. Below is a stripped example of your code that does what you are looking for.
\documentclass[landscape, 12pt]{report}
\usepackage{graphicx}
\pagestyle{empty}
\begin{document}
\noindent Here is some text
$$\resizebox{.9 \textwidth}{!} { a + b }$$
and here is some more.
\end{document}
Here the .9 determines how much of the width you'd like to take up, in this case I choose 90% though you can fit to your liking. The ! as the second argument will preserve the aspect ratio.
Giving credit where it is due, a very similar question was answered on Stack Exchange recently about shrinking the equation. In both cases the \resizebox should suffice, though it is not recommended. Personally, I would consider splitting the equation. Having an inconsistent math font size can be a typographical nightmare.
Examples
Here the argument to \resizebox is set to 1.0 \textwidth (compiled with pdflatex):
In this example it is set to 0.2 \textwidth
-
Your solution looks like a good one. But I tried implement it in kile and the a+b have the same size, even changing the .9 to .1, .99, 5.5. What's going on? – GarouDan Nov 21 '11 at 20:16
@GarouDan Hard to tell without seeing what you are seeing. I've added a picture so you can see what the final result looks like, I've slightly modified the code by adding some outside text so you can get a feel for how the equation scales. – Hooked Nov 21 '11 at 20:30
This is very strange. Using this code I got this image outup in my dvi. I'm using kile and using ubuntu 10.04 lts =// if helps. – GarouDan Nov 21 '11 at 20:53
@GarouDan try compiling it with pdflatex from the command line, that's how the examples above were produced. – Hooked Nov 21 '11 at 21:02
lol @Hooked. Using pdf (pdflatex) works (I usually never uses pdf, sorry). Why not with dvi (I use latex and then see the dvi)? Thanks, I think this ends the question. – GarouDan Nov 21 '11 at 21:18
Breaking huge fractions certainly is tricky, and I don't think there exists an automated solution for that.
So first off, let's see how your formula looks like (examples in plain-format):
\input amssym.def
\def\P{{\rm P}}
\def\E{\Bbb E}
$$\P(H_h|E_1,E_2,\dots,E_e,\dots E_\E) = { \P(H_h) \P(E_1|H_h) \P(E_2|H_h,E_1) \dots \P(E_e|H_h,E_1,E_2,\dots,E_{e-1},E_{e+1}\dots,E_\E) \ldots \P(E_\E|H_h,E_1,E_2,\dots,E_\E-1) \over \P(E_1,E_2,\dots,E_e,\dots,E_\E) }$$
Oh my, we ran out of paper!
Knuth gives an example in the TeXbook how you can break the formula (exercise 19.9), and applying that solution here isn't exactly straight-forward, for there is many ways to do the splitting. Let's start off with two-line split:
$$\P(H_h|E_1,E_2,\dots,E_e,\dots E_\E) = {\displaystyle{\P(H_h) \P(E_1|H_h) \P(E_2|H_h,E_1) \dots \P(E_e|H_h,E_1,E_2,\dots,E_{e-1},E_{e+1}\dots,E_\E) \ldots \atop \hfill\P(E_\E|H_h,E_1,E_2,\dots,E_\E-1) } \over \P(E_1,E_2,\dots,E_e,\dots,E_\E) }$$
Well, we didn't run out of paper, but we were left with an overfull box.
Maybe if we introduced a not-so-natural break instead:
$$\P(H_h|E_1,E_2,\dots,E_e,\dots E_\E) = { \displaystyle{ \P(H_h) \P(E_1|H_h) \P(E_2|H_h,E_1) \dots \P(E_e|H_h,E_1,E_2, \hfill \atop \qquad \dots,E_{e-1},E_{e+1}\dots,E_\E) \ldots \P(E_\E|H_h,E_1,E_2,\dots,E_\E-1) } \over \P(E_1,E_2,\dots,E_e,\dots,E_\E) }$$
Now the space-requirements are better, albeit with a cost.
You could go really over the board and split it into three lines:
$$\P(H_h|E_1,E_2,\dots,E_e,\dots E_\E) = { \displaystyle{ \displaystyle{ \P(H_h) \P(E_1|H_h) \P(E_2|H_h,E_1) \dots \hfill \atop \qquad \P(E_e|H_h,E_1,E_2,\dots,E_{e-1},E_{e+1}\dots,E_\E) \ldots } \atop \hfill \P(E_\E|H_h,E_1,E_2,\dots,E_\E-1) } \over \P(E_1,E_2,\dots,E_e,\dots,E_\E) }$$
But that might be a tad too funky. I dunno.
So, how would an automated solution choose? I guess it would be really tricky.
-
Another option is to set the RHS as \frac {1}{P(E_1,...E_{E}} \Big[ P(H_h) ... \Big]. Then the term in the brackets can be split into multiple lines using aligned or multlined. – Aditya Nov 22 '11 at 0:21
Not sure how much this matters, but you may want to replace E_\E-1 with E_{\E-1} (towards the very end of the long numerator expressions) in the various examples you provide. – Mico Dec 22 '12 at 16:26
You could make the fraction smaller using \textstyle:
$$P(H_h|E_1,E_2,\ldots ,E_e,\ldots E_{\mathbb{E}}) =\textstyle\frac{P(H_h) P(E_1|H_h) P(E_2|H_h,E_1) \text{\ldots P} (E_e|H_h,E_1,E_2,\ldots ,E_{e-1},E_{e+1} \ldots,E_{\mathbb{E}})\text{\ldotsP} (E_{\mathbb{E}}|H_h,E_1,E_2,\ldots ,E_{\mathbb{E}-1})} { P(E_1,E_2,\ldots,E_e, \ldots ,E_{\mathbb{E}})}$$
Or you could use \\ within the amsmath environment multline to introduce a line-break:
\begin{multline}
P(H_h|E_1,E_2,\ldots ,E_e,\ldots E_{\mathbb{E}})=\\
\frac{P(H_h) P(E_1|H_h)
P(E_2|H_h,E_1) \text{$\ldots$P}
(E_e|H_h,E_1,E_2,\ldots ,E_{e-1},E_{e+1} \ldots,E_{\mathbb{E}})\text{$\ldots$P}
(E_{\mathbb{E}}|H_h,E_1,E_2,\ldots ,E_{\mathbb{E}-1})}
{ P(E_1,E_2,\ldots,E_e, \ldots ,E_{\mathbb{E}})}
\end{multline}
Of course, it looks nicer with the equals sign on the same line as the fraction, but your margins are too big for that.
With the line-break moved, the equation becomes:
\begin{multline}
P(H_h|E_1,E_2,\ldots ,E_e,\ldots E_{\mathbb{E}})\\
=\frac{P(H_h) P(E_1|H_h)
P(E_2|H_h,E_1) \text{$\ldots$P}
(E_e|H_h,E_1,E_2,\ldots ,E_{e-1},E_{e+1} \ldots,E_{\mathbb{E}})\text{$\ldots$P}
(E_{\mathbb{E}}|H_h,E_1,E_2,\ldots ,E_{\mathbb{E}-1})}
{ P(E_1,E_2,\ldots,E_e, \ldots ,E_{\mathbb{E}})}
\end{multline}
And then you can change the page margins using the geometry package options:
\usepackage[margin=1in,landscape]{geometry}
-
This is really helpfull @rdhs. Thanks so much. I need this this equations as large as possible to cut and use as a image in my presentation. – GarouDan Nov 21 '11 at 13:17
Unfortunally I need something more. Something like how change the size of a equation? Is there a scale to equations who I can explicity change the size in inches or points or cm's? – GarouDan Nov 21 '11 at 14:23
Package resizegather can automatically shrink equations of environment gather of package amsmath to fit the line width.
The following example compares the equation using \textstyle of rdhs' answer with resizing the overlarge equation (too large by 148.64104pt):
\documentclass[landscape, 12pt]{report}
\usepackage[landscape]{geometry}
\usepackage{amsmath,amssymb}
\usepackage{resizegather}
\begin{document}
\begin{gather}
\label{eq-tfrac}
P\left(H_h|E_1,E_2,\ldots ,E_e,\ldots E_{\mathbb{E}}\right)=\tfrac{P\left(H_h\right) P\left(E_1|H_h\right) P\left(E_2|H_h,E_1\right) \text{$\ldots$P}
\left(E_e|H_h,E_1,E_2,\ldots ,E_{e-1},E_{e+1} \ldots, E_{\mathbb{E}}\right) \text{$\ldots$P}
\left(E_{\mathbb{E}}|H_h,E_1,E_2,\ldots ,E_{\mathbb{E}-1}\right)}{ P\left(E_1,E_2,\ldots,E_e, \ldots ,E_{\mathbb{E}}\right)}
\\\label{eq-resized}
P\left(H_h|E_1,E_2,\ldots ,E_e,\ldots E_{\mathbb{E}}\right)=\frac{P\left(H_h\right) P\left(E_1|H_h\right) P\left(E_2|H_h,E_1\right) \text{$\ldots$P}
\left(E_e|H_h,E_1,E_2,\ldots ,E_{e-1},E_{e+1} \ldots, E_{\mathbb{E}}\right) \text{$\ldots$P}
\left(E_{\mathbb{E}}|H_h,E_1,E_2,\ldots ,E_{\mathbb{E}-1}\right)}{ P\left(E_1,E_2,\ldots,E_e, \ldots ,E_{\mathbb{E}}\right)}
\end{gather}
\end{document}
-
Here's a solution using the mathtools package and its \splitfrac command; note that the \splitfrac directives may be nested. Overall, this solution looks very much like the third solution provided earlier by @morbusg. The advantage of the new solution may lie in its not having to use the TeX "primitive" command \atop.
Observe that there's no longer a need to typeset the formula in landscape mode. In addition, I've replaced some of the \ldots with \cdots, so as to better distinguish between items in a simple math list and items in a multiplicative list. Moreover, I've replaced the | vertical bars with \mid directives; the latter provide better horizontal spacing. Finally, I've gotten rid of the \left and \right directives, as they actually don't do anything in terms of resizing the parentheses in the present example.
\documentclass{report}
\usepackage[margin=1in]{geometry}
\usepackage{mathtools, amssymb}
\begin{document}
$$\label{Equation:Naive_Bayes_Classifier} P(H_h\mid E_1,E_2,\dots ,E_e,\dots E_{\mathbb{E}})= \frac{\left( % place large parens around entire numerator expression \splitfrac{P(H_h)\, P(E_1\mid H_h) \, P(E_2\mid H_h,E_1) \cdots }{ \splitfrac{ P(E_e\mid H_h,E_1,E_2,\dots ,E_{e-1},E_{e+1} \dots, E_{\mathbb{E}}) \cdots }{ P(E_{\mathbb{E}}\mid H_h,E_1,E_2,\dots, E_{\mathbb{E}-1}) } % end of inner splitfrac } % end of outer splitfrac \right)} { P(E_1,E_2,\dots,E_e,\dots,E_{\mathbb{E}})}$$
\end{document}
If you want a bit more vertical whitespace between the three lines of the numerator expression, you could replace the \splitfrac directives with \splitdfrac instructions.
-
Okay, your comment really clarifies what you want, and there's a better solution for that. (I'm not quite sure if it's appropriate to post a separate answer, but here goes.)
If you want the page to grow to fit the equation, then the best solution is to use the standalone document class and the varwidth package. You can also remove the equation numbering:
\documentclass[12pt]{standalone}
\usepackage{varwidth}
\usepackage[utf8x]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsmath, amssymb, graphics, setspace}
\newcommand{\mathsym}[1]{{}}
\newcommand{\unicode}[1]{{}}
\newcounter{mathematicapage}
\begin{document}
\begin{varwidth}{50in}
\begin{equation*}
P(H_h|E_1,E_2,\ldots ,E_e,\ldots E_{\mathbb{E}})
=\frac{P(H_h) P(E_1|H_h)
P(E_2|H_h,E_1) \text{$\ldots$P}
(E_e|H_h,E_1,E_2,\ldots ,E_{e-1},E_{e+1} \ldots,E_{\mathbb{E}})\text{$\ldots$P}
(E_{\mathbb{E}}|H_h,E_1,E_2,\ldots ,E_{\mathbb{E}-1})}
{ P(E_1,E_2,\ldots,E_e, \ldots ,E_{\mathbb{E}})}
\end{equation*}
\end{varwidth}
\end{document}
This gives a PDF file that can be converted directly to PNG and put into slides, no cropping required. You could probably get Mathematica to change its output like this automatically, but if not you could use sed to automate the substitutions.
-
When I tryed to run your code in Kile (Ubuntu 10.04 LTS) I got, File 'standalone.cls' not found. \usepackage. Where I can get this package (no result in google yet =/)? – GarouDan Nov 21 '11 at 14:42
Here's a standalone.cls: tug.org. And you can scale the page however you want. If you include it in another LaTeX doc (e.g., beamer slides), do something like \includegraphics[width=8 in]{bigeqn.pdf}. If you convert it to a PNG using GraphicsMagick, so something like gm convert -monochrome -geometry 4800x -density 600 bigeqn.pdf bigeqn.png (4800 = 8 in x 600 ppi). – rdhs Nov 21 '11 at 14:47
Sorry, I couldn't solve the problem yet. Please see this code in pastebin. (I have installed standalone package)I tried several things but doesn't worked very well. Can you write a new code for me? – GarouDan Nov 21 '11 at 15:30
Thanks you so much. Now, with Hooked help (using pdf's instead dvi) I can see your idea works fine. Really thanks. If I could I'd like accept your solution as answer too. So, if someone like this solution as I please vote up. Cya. – GarouDan Nov 21 '11 at 21:23 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 4, "x-ck12": 0, "texerror": 0, "math_score": 0.9017196297645569, "perplexity": 2576.971665234532}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-52/segments/1419447548479.105/warc/CC-MAIN-20141224185908-00012-ip-10-231-17-201.ec2.internal.warc.gz"} |
https://www.zbmath.org/?q=an%3A0826.35094 | ×
# zbMATH — the first resource for mathematics
The Navier-Stokes equation for an incompressible fluid in $$\mathbb{R}^ 2$$ with a measure as the initial vorticity. (English) Zbl 0826.35094
The author studies global in time solutions of the Navier-Stokes equation for an incompressible fluid in $$\mathbb{R}^2$$ $\partial_t u - \Delta u + \Pi \partial (u \otimes u) = 0, \quad u=\Pi u,$ where $$\Pi$$ is the projection onto solenoidal vectors along gradients, $$u \otimes u$$ is a tensor with $$jk$$-component $$u_k u_j$$ and $$\partial (u \otimes u)$$ is a vector with $$j$$-th component $$\partial_k (u_ku_j) = u_k \partial_k u_j$$. Besides, the equation for the associated vorticity $$\zeta = \partial_1 u_2 - \partial_2 u_1$$ is studied: $\partial_t \zeta - \Delta \zeta + \partial \cdot (\zeta S* \zeta) = 0, \quad S(x) = (2 \pi)^{-1} |x |^{-2} (x_2, -x_1).$ The following estimates for $$u$$ and $$\zeta$$ in terms of the total variation $$|\omega |$$ of the initial vorticity $$\omega$$ are obtained: \begin{aligned} t^{1 - 1/q} |\zeta (t) |_q \leq k^{-(1- 1/q)} |\omega |, \quad & q \in [1, \infty) \\ t^{1/2 - 1/p} |u(t) |_p \leq \sigma_{2p/(p + 2)} k^{- (1/2 - 1/p)} |\omega |,\quad & p \in (2, \infty). \end{aligned} Global estimates for derivatives of $$\zeta$$ and $$u$$ are deduced \begin{aligned} t^{n + k/2 + 1 - 1/q} \biggl |\partial^n_t (- \Delta)^{k/2} \zeta (t) \biggr |_q \leq K, \quad & q \in (1, \infty), \\ t^{n + k/2 + 1/2 - 1/p} \biggl |\partial^n_t (-\Delta)^{k/2} u(t) \biggr |_p \leq K, \quad & p \in (1, \infty). \end{aligned} It is shown that $$|\zeta (t) |_q$$ is monotone nonincreasing in $$t > 0$$ for each fixed $$q \in [1, \infty)$$. Uniqueness is proved under a certain condition on the atomic part of $$\omega$$.
##### MSC:
35Q30 Navier-Stokes equations 35G10 Initial value problems for linear higher-order PDEs 35K25 Higher-order parabolic equations 35K05 Heat equation 76D05 Navier-Stokes equations for incompressible viscous fluids | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.999891996383667, "perplexity": 1025.2349567110134}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-17/segments/1618038060927.2/warc/CC-MAIN-20210411030031-20210411060031-00612.warc.gz"} |
http://math.stackexchange.com/questions/173441/book-suggestion-for-linear-algebra-2 | # Book suggestion for linear algebra “2”
I am almost finishing Gilbert Strang's book "An introduction to linear algebra" (plus video lectures at MIT OCW). First and foremost, I would like to suggest this course for everyone. It has been incredibly illuminating.
I would like to continue studying linear algebra, with particular focus on different properties of matrices and the transition to more general linear spaces (I am a physicist so Hilbert spaces and etc. are of particular interest).
Does anyone have a a good recommendation of books/resources/etc.?
-
Hoffman and Kunze? – Inquest Jul 21 '12 at 0:10
@Inquest, H&K is probably too abstract. It's a nice book, though. – lhf Jul 21 '12 at 0:20
As a warning, I have seen a textbook on infinite-dimensional linear algebra advise that one forget everything one has learned about finite-dimensional linear algebra, as any intuition you have for the subject it is just as likely to be misleading as it is to be helpful. – Hurkyl Jul 21 '12 at 0:27
wikipedia is actually pretty good, and you can further reading references. – chaohuang Jul 21 '12 at 3:55
How about reading the chapters on vector spaces and linear transformations from I. N. Herstein's Topics in Algebra. Don't forget to do the exercises. – Shahab Jul 21 '12 at 10:08
I have to suggest the somewhat underrated Matrix Analysis by Horn and Johnson (the first edition was used for my ALA class at NCF.) They take a wonderfully concrete approach to most topics encountered in a second linear algebra course (Schur Decomposition, Spectral Theorem for Normal Operators, Jordan Canonical Form, Singular Value Decomposition) while adding a lot of other nice things into the mix. The fourth chapter on Hermitian Matrices talks about the Rayleigh Ritz Theorem and variational characterization of eigenvalues, which I imagine come up a lot in serious study of classical mechanics. Chapter five discusses finite dimensional inner product / normed / pre-normed spaces in terms of algebraic, analytic, and geometric properties. They include a discussion of completeness and the $l^p$ norms, which I guess could be seen as a preview of Hilbert Space Theory. There are also nice sections on the Gersgorin circle theorem and numerically solving linear systems.
I think it's a wonderful choice for any student, but especially a non-mathematician. The proofs are rigorous and sometimes tedious but always understandable. Typically, things are proved in an algorithmic fashion rather than through diagram chasing or algebraic artifice (nary a mention of finitely generated modules over a principal ideal domain.) My only complaint is that there are a fair number of results assumed regarding matrix algebra and determinants which wouldn't typically appear in a linear algebra course - references for these are typically not too hard to find though.
-
You could try Meyer's Matrix Analysis and Applied Linear Algebra or Lax's Linear Algebra and its Applications.
-
I took a "second semester" course in linear algebra out of Friedberg, Isnel and Spence's book Linear Algebra and found it to be a good read and a really useful reference.
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An old edition of Friedberg, Insel & Spence along with this video course which follows the book.
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It may also be that, for applications (whether within or without mathematics proper) the label "linear algebra" is misleading. I'd think that future physicists might care more about (positive-attitude) "functional analysis" than what the traditional mathematics enterprise calls "linear algebra". Depends.
There is also the conflict, alluded-to in comments and answers, that the orthodox/traditional math texts "advancing" linear algebra are a bit aggressive in demanding compliance-in-orthodoxy from the reader. Contemporary math-phys or phys students may bridle at this, and reasonably so, considering that it is mostly due to the typical curricular/textbook inertia.
E.g., the earlier remark that people are abjured by (presumably orthodox) authors/authorities to "forget about finite-dimensional linear algebra to address infinite-dimensional" disserves everyone (even if it can be interpreted as being "true" in some way). That is, while the naive-est extrapolation of finite-dimensional linear algebra proves inadequate, it is nevertheless the model for what everyone (if they were candid) would like to be true. Thus, the task partly becomes appraisal of how far from this ideal we find ourselves in any particular real-life situation.
The main "life-lesson" is about "continuous spectrum", which is exemplified by Fourier transform and Fourier inversion on the real line. On one hand, "everything is fine", but, when juxtaposing to (perhaps naive) linear algebra, there are problems. But, in fact, it truly is fine, when one adjusts one's notion of the range of happy, useful, extensible answers.
Peter Lax's functional analysis book is certainly vastly more sophisticated than upper-division linear algebra books, but th'guy is very practical-minded, and is not adversarial as a writer. His interests in PDE are physical.
My own notes about functional analysis and linear algebra, at my web page, while not pretentious or anti-physical, are written from a viewpoint which may not be the most useful to the questioner, though, who knows? At least I tried to be honest. :)
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I recommend Halmos' Finite Dimensional Vector Spaces. Halmos was a functional analyst and an expert on Hilbert spaces. I read that the goal of the text is to present finite dimensional vector space theory as the "easy case" of Hilbert space theory.
Added later: You might also check out Janich's book. I noticed it had problem sections titled, "For physicists."
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I should note that the book is fairly abstract, though. – user59083 Jul 27 '13 at 16:36 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6765608191490173, "perplexity": 853.6630502646875}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-35/segments/1440644066275.44/warc/CC-MAIN-20150827025426-00330-ip-10-171-96-226.ec2.internal.warc.gz"} |
http://math.stackexchange.com/questions/777493/do-the-kolmogorovs-axioms-permit-speaking-of-frequencies-of-occurence-in-any-me | # Do the Kolmogorov's axioms permit speaking of frequencies of occurence in any meaningful sense?
It is frequently stated (in textbooks, on Wikipedia) that the "Law of large numbers" in mathematical probability theory is a statement about relative frequencies of occurrence of an event in a finite number of trials or that it "relates the axiomatic concept of probability to the statistical concept of frequency". Isn't this is a methodological mistake of ascribing an interpretation to a mathematical term, perhaps relying too much on the colorful language, that does not at all follow from how this term is mathematically defined? Recall the typical derivation of the WLLN:
Let $X_1, X_2, ..., X_n$ be a sequence of n independent and identically distributed random variables with the same finite mean $\mu$, and with variance $\sigma^2$ and let:
$\overline{X}=\tfrac1n(X_1+\cdots+X_n)$
We have:
$E[\overline{X}] = \frac{E[X_1+...+X_n]}{n} = \frac{E[X_1]+...+E[X_n]}{n} = \frac{n\mu}{n} = \mu$ $Var[\overline{X}] = \frac{Var[X_1+...+X_n]}{n^2} = \frac{Var[X_1]+...+Var[X_n]}{n^2} = \frac{n\sigma^2}{n^2} = \frac{\sigma^2}{n}$
And from Chebyshev's inequality:
$P(|\overline{X}-\mu|>\epsilon) \le \frac{\sigma^2}{n\epsilon^2}$
And so X is said to converge in probability to $\mu$.
Now consider what is strictly speaking the meaning of this expression in the axiomatic framework it is derived in:
$P(|\overline{X}-\mu|>\epsilon) \le \frac{\sigma^2}{n\epsilon^2}$
$P()$, everywhere it occurs in the derivation, is known only to be a number satisfying Kolmogorov's axioms, so a number between 0 and 1, and so forth, but none of the axioms introduce any theoretical equivalent of the intuitive notion of frequency. If additional assumptions about $P()$ are not made, the sentence can obviously not be interpreted at all, but what is also important the theoretical mean $\mu$ is not necessarily the mean value in an infinite number of trials, $\overline{X}$ is not necessarily the mean value from n trials, and so forth. Consider an experiment of tossing a fair coin repeatedly - quite obviously, nothing in Kolmogorov's axioms enforces using 1/2 for the probability of heads, you could just as well use $1/\sqrt{\pi}$, yet the derivation continues to "work", except the meaning of the various variables is not in agreement with their intuitive interpretations. The $P()$ might still mean something, it might be a quantification of an absurd belief of mine, the mathematical derivation continues be true regardless, in the sense that as long as the initial $P()'s$ satisfy axioms, theorems about other $P()'s$ follow, and with Kolmogorov's axioms providing only weak constraints on and not a definition of $P()$, it's basically only symbol manipulation.
This "relative frequency" interpretation frequently given seems to rest on an additional assumption, and this assumption seems to be a form of the law of large numbers itself. Consider this fragment from Kolmogorov's Grundbegriffe on applying the results of probability theory to the real world:
We apply the theory of probability to the actual world of experiment in the following manner:
...
4) Under certain conditions, which we shall not discuss here, we may assume that the event A which may or may not occur under conditions S, is assigned a real number P(A) which has the following characteristics:
a) One can be practically certain that if the complex of conditions S is repeated a large number of times, n, then if m be the number of occurrences of event A, the ratio m/n will differ very slightly from P(A).
Which seems equivalent to introducing the weak law of large numbers in a particular, slightly different form, as an additional axiom.
Meanwhile, many reputable sources contain statements that seem completely in opposition to the above reasoning, for example Wikipedia:
It follows from the law of large numbers that the empirical probability of success in a series of Bernoulli trials will converge to the theoretical probability. For a Bernoulli random variable, the expected value is the theoretical probability of success, and the average of n such variables (assuming they are independent and identically distributed (i.i.d.)) is precisely the relative frequency.
This seem to be mistaken already in claiming that from a mathematical theorem anything can follow about empirical probability (the page on which defines it as the relative frequency in actual experiment), but there are many more subtle claims that technically also seem erroneous from the above considerations:
The LLN is important because it "guarantees" stable long-term results for the averages of random events.
Note that the Wikipedia article about LLN claims to be about the mathematical theorem, not about the empirical observation, which was also historically sometimes been called the LLN. It seems to me that LLN does nothing to "guarantee stable long-term results", for as stated above those stable long-term results have to be assumed in the first place for the terms occuring in the derivation to have the intuitive meaning we typically ascribe to them, not to mention something has to be done to at all interpret $P()$ in the first place. Another instance from Wikipedia:
According to the law of large numbers, if a large number of six-sided die are rolled, the average of their values (sometimes called the sample mean) is likely to be close to 3.5, with the precision increasing as more dice are rolled.
Does this really follow from the mathematical theorem? In my opinion, the interpretation of the theorem that is used here, rests on assuming this fact. There is a particularly vivid example in the "Treatise on probability" by Keynes of what happens when one follows the WLLN with even a slight deviation from this initial assumptions of p's being the relative frequencies in the limit of an infinite number of trials:
The following example from Czuber will be sufficient for the purpose of illustration. Czuber’s argument is as follows: In the period 1866–1877 there were registered in Austria
m = 4,311,076 male births
n = 4,052,193 female births
s = 8,363,269
for the succeeding period, 1877–1899, we are given only
m' = 6,533,961 male births;
what conclusion can we draw as to the number n of female births? We can conclude, according to Czuber, that the most probable value
n' = nm'/m = 6,141,587
and that there is a probability P = .9999779 that n will lie between the limits 6,118,361 and 6,164,813. It seems in plain opposition to good sense that on such evidence we should be able with practical certainty P = .9999779 = 1 − 1/45250 to estimate the number of female births within such narrow limits. And we see that the conditions laid down in § 11 have been flagrantly neglected. The number of cases, over which the prediction based on Bernoulli’s Theorem is to extend, actually exceeds the number of cases upon which the à priori probability has been based. It may be added that for the period, 1877–1894, the actual value of n did lie between the estimated limits, but that for the period, 1895–1905, it lay outside limits to which the same method had attributed practical certainty.
Am I mistaken in my reasoning above, or are all those really mistakes in the Wikipedia? I have seen similar statements all over the place in textbooks, and I am honestly wondering what I am missing.
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This is a much more concrete version of the question I asked earlier math.stackexchange.com/questions/775788/…, and that I would ask the dear moderators to delete, as it was too vague to be useful. Please forgive me partially reposting something, I hope you will understand making a complicated reasoning clear does not always come easy or quickly. I will not post anything similar again. – Jarosław Rzeszótko May 1 '14 at 20:07
The law of large numbers is a red herring, I think: you're stuck on the idea of expressing "physical" quantities (such as the result of a frequency-measuring experiment) as random variables. – Hurkyl May 1 '14 at 21:18
You can express a frequency-measuring experiment as X-dash as defined above regardless of what P() is, but the moment you take expectations, and multiply the P()'s of particular values of the random variable by the actual values, you end up with a statement about what we intuitively think as the mean value from repetitions of the experiment only with additional assumptions about P()'s that are not in the axioms of Kolmogorov. That is indeed where my disagreement with Wikipedia and its interpretation of LLN has its roots, but you seem to claim I am simply misunderstanding something here, right? – Jarosław Rzeszótko May 1 '14 at 21:53
better work the example out what is really the variance. – Willemien May 2 '14 at 6:43
@Willemien I am not sure what you mean? – Jarosław Rzeszótko May 2 '14 at 6:58
Kolmogorov's axioms, if one were to make an assumption about the distribution of the random variable $X_i$, could be used to derive the distribution of the random variable $\bar{X}$. Notice in the last statement that since $X_i$ is a random variable, $\bar{X}$ is also a random variable. The fact that $\bar{X}$ is a random variable means that there is a probability measure for the random variable $\bar{X}$. The beauty of the WLLN is that so long as both $\mu$ and $\sigma^2$ are finite, no assumptions about the measure $P()$ must be made in order to derive that $\bar{X_n}$ converges in probability to $\mu$. I agree with Hurkyl. Perhaps this post will help with the concept of a random variable http://stats.stackexchange.com/questions/50/what-is-meant-by-a-random-variable
You do make a good point, however, about whether or not the assumptions that the $X$'s are independent and identically distributed random variables may not be true in practice, which is the problem alluded to in the Keynes example.
The example regarding dice appears to rely on the assumption that the die is fair, which may or may not be reasonable depending on how the die is constructed and rolled. However, it seems reasonable to assume that there exists appropriate setups of a dice rolling experiments for which the rolls are $i.i.d$ random variables with a probability measure $P$. In such a case, it does follow from the WLLN that $\bar{X}$ would indeed converge to $\mu$.
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I have no doubts that X-dash converges to mu in the framework of the Kolmogorov's axioms, but the question is whether this allows to draw any interpretable conclusions. Based only on the axioms, mu and X-dash are not interpretable as the average value from a large result of trials, they are simply weighted averages of some set of values using the, arbitrary to some extent, measure P(). Similarly when "relative frequency" is mentioned in the context of the theory, I think it does not really translate into real world relative frequency, unless the WLLN is assumed as true a priori. – Jarosław Rzeszótko May 3 '14 at 13:04
In other words, it seems to me people widely fail to notice that when "relative frequency" is spoken of in the context of probability theory, it only corresponds to our intuitive notion of "relative frequency", if one makes assumptions additional to the Kolmogorov's axioms, and the assumption needed is the WLLN itself. Hence no conclusions about real world situations follow purely from the WLLN as derived from the axioms. – Jarosław Rzeszótko May 3 '14 at 13:05
By the way, the trials in the Keynes examples are independent and identically distributed, the problem is that the probabilities are slightly off from the ideal theoretical relative frequency in an infinite limit of trials. While such P()'s satisfy the axioms, and the formal mathematics stays "true", you see that the result does not seem to be true anymore, and that is because the intuitive interpretation of the various terms in the derivation does not hold anymore. This example shows the WLLN has to be assumed a priori for the usual real world interpretation to hold. – Jarosław Rzeszótko May 3 '14 at 13:19
Based on the axions, $\mu$, the expected value is calculated mathematically and is not based on a relative frequency argument. You are correct the large trial interpretation of $\mu$ that it is the average of a large number of trials would imply that WLLN would be circular, but I would argue that is based solely on that particular interpretation of $\mu$. – jsk May 3 '14 at 16:23
In regards to the relative frequency interpretation of probability, that is again only the frequentist interpretation of probability. There is nothing in Kolmogorov's axioms which states that you should invoke the relative frequency interpretation of probability. – jsk May 3 '14 at 16:27
What you're missing is that the derivation of the WLLN is allowed to use, not only the Kolmogorov axioms, but also the assumption stated in the theorem: "The $X_1,X_2,\dots,X_n$ are a sequence of $n$ independent and identically distributed random variables with the same finite mean μ, and with variance $σ^2$". So, for example, if we are tossing a fair coin, we know that μ=1/2 (this is what "fair coin" means in probability theory), not $1/\sqrt\pi$. And likewise, in a Bernoulli trial, we are given the actual mean to which the observed probabilities are supposed to converge. And Keynes/Czuber's example isn't a valid application of the LLN because we are not given the actual mean and standard deviation.
So the first two claims in the Wikipedia article are basically correct (except that "will converge to the theoretical probability" should read "will converge in probability to the theoretical probability"; the probability that the observed values do not converge to the theoretical value is 0; but it might happen anyway).
However, the third claim, "According to the law of large numbers, if a large number of six-sided die are rolled, the average of their values (sometimes called the sample mean) is likely to be close to 3.5, with the precision increasing as more dice are rolled." doesn't follow, since we don't know a priori that rolling a six-sided die constitutes a Bernoulli trial. Looking at the context, it seems that the fairness of the die is meant as an ambient assumption, since one of the preceding sentences is "For example, a single roll of a six-sided die produces one of the numbers 1, 2, 3, 4, 5, or 6, each with equal probability."
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As i have stated in another question, the (axiomatic) theory of probability is a mathematical framework extrapolating a specific model of physical processes.
One of our professors on stochastic theory and probability used to say: "the (application of the) theory of probability only has meaning for processes/systems which exhibit statistical stability".
It is like applying Group theory or Field theory where it does not apply (this makes the confusion betwen the formulation of probability theory and its application and interpretation to the point).
This ansers both the question and the specific counter examples and in a sense unifies the frequestist and bayesian viewpoints.
(btw Jaynes' exposition is one of my favorites but strongly disagree on the subjectivist view which i can debate quite well, but this is not of the essence here).
- | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9378516674041748, "perplexity": 374.513805139013}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-18/segments/1429246640001.64/warc/CC-MAIN-20150417045720-00221-ip-10-235-10-82.ec2.internal.warc.gz"} |
https://forums.penny-arcade.com/discussion/comment/40847284 | # [Programming] Reinventing equality, one language at a time
## Posts
• Registered User regular
halkun wrote: »
For me, if the "if" is only one line, I will bracket it up too. It keeps things from "leaking". Also, it reminds me of my BASIC days. If "else" only has one line, I'll bracket it too.
if (foo) {bar()} else {baz();}
I should be using a ternary, but I can't parse those right
I had the worst time with them (so simple seeming, right?) until I hit on:
Question ? Yes : No (At least the Swift pattern). Something in my brain went "Ooooooh okay!" then.
• Registered User regular
dporowski wrote: »
halkun wrote: »
For me, if the "if" is only one line, I will bracket it up too. It keeps things from "leaking". Also, it reminds me of my BASIC days. If "else" only has one line, I'll bracket it too.
if (foo) {bar()} else {baz();}
I should be using a ternary, but I can't parse those right
I had the worst time with them (so simple seeming, right?) until I hit on:
Question ? Yes : No (At least the Swift pattern). Something in my brain went "Ooooooh okay!" then.
I like to format them as:
Question
? Yes
: No
• A collection of mediocre hats Seattle, WARegistered User regular
I love the ternary operator, but I get why they are controversial, and if I am working under a style guide or a language that forbids them, I can live with that.
"I resent the entire notion of a body as an ante and then raise you a generalized dissatisfaction with physicality itself" -- Tycho
• Registered User regular
Just use languages that treat the if as an expression, problem solved
Hey I made a game, check it out @ http://ifallingrobot.com/. (Or don't, your call)
• sword criminal mad onlineRegistered User regular
edited February 2019
entering week 3 of a major field test.... 99.89% crash free sessions
aka 1 crash after 2.2 weeks of heavy use in primitive conditions
looks like the hardest longest rewrite of my life has paid off
Jasconius on
• Registered User regular
I'm reading about the history of gets, the morris worm, scanf, fgets, and getline in C
and it just seems like programmers went from thinking "there's no way the user will be that much of a jerk" to "the user is a total jerk holy shit"
• Registered User regular
edited February 2019
For fun I looked at the morris worm source* and found this declaration and comment:
https://github.com/arialdomartini/morris-worm/blob/master/worm.c#L26
object objects[69]; /* Don't know how many... */
nice
*it's probably actually a decompilation, not the original source
Dehumanized on
• Registered User regular
edited February 2019
I love the ternary operator, but I get why they are controversial, and if I am working under a style guide or a language that forbids them, I can live with that.
I don't mind them for simple things, but if you're nesting a bunch of code in a ternary I think they are messy and become hard to read very fast.
e: And yes, if's as expressions is a nice language feature.
GnomeTank on
Sagroth wrote: »
Oh c'mon FyreWulff, no one's gonna pay to visit Uranus.
Steam: Brainling, XBL / PSN: GnomeTank, NintendoID: Brainling, FF14: Zillius Rosh SFV: Brainling
• Registered User regular
For fun I looked at the morris worm source* and found this declaration and comment:
https://github.com/arialdomartini/morris-worm/blob/master/worm.c#L26
object objects[69]; /* Don't know how many... */
nice
*it's probably actually a decompilation, not the original source
Nice
• The Team Chump USARegistered User regular
edited February 2019
tyrannus wrote: »
For fun I looked at the morris worm source* and found this declaration and comment:
https://github.com/arialdomartini/morris-worm/blob/master/worm.c#L26
object objects[69]; /* Don't know how many... */
nice
*it's probably actually a decompilation, not the original source
Nice
?
templewulf on
Twitch.tv/FiercePunchStudios | PSN | Steam | Discord | SFV CFN: templewulf
• The Team Chump USARegistered User regular
GnomeTank wrote: »
I love the ternary operator, but I get why they are controversial, and if I am working under a style guide or a language that forbids them, I can live with that.
I don't mind them for simple things, but if you're nesting a bunch of code in a ternary I think they are messy and become hard to read very fast.
e: And yes, if's as expressions is a nice language feature.
I think they're great for expressions, like the rvalue in an assignment or a cout.
Basically, if I'm going to do the same action and the conditional just determines what value I pass into the action, a ternary helps make the "verbs" clear.
Twitch.tv/FiercePunchStudios | PSN | Steam | Discord | SFV CFN: templewulf
• Building Planet Busters Tasting FruitRegistered User regular
Ternaries are great until you abuse them
• How you doin'? Registered User regular
Oh you saw the 6 level deep ternary I used the other day then?
not a doctor, not a lawyer, examples I use may not be fully researched so don't take out of context plz, don't @ me
• Registered User regular
int median(int a, int b, int c) {
return (a<b) ? (b<c) ? b : (a<c) ? c : a : (a<c) ? a : (b<c) ? c : b;
}
• Registered User regular
bowen wrote: »
Oh you saw the 6 level deep ternary I used the other day then?
I sometimes feel like people take "concise" way too far and forget about readability.
3ds: 4983-4935-4575
• Registered User regular
edited February 2019
TelMarine wrote: »
bowen wrote: »
Oh you saw the 6 level deep ternary I used the other day then?
I sometimes feel like people take "concise" way too far and forget about readability.
I feel a mention of https://en.wikipedia.org/wiki/Obfuscated_Perl_Contest is topical.
Edit: Or worse, from the C inspiration for it:
B,i,y,u,b,I[411],*G=I,x=10,z=15,M=1e4;X(w,c,h,e,S,s){int t,o,L,E,d,O=e,N=-M*M,K
=78-h<<x,p,*g,n,*m,A,q,r,C,J,a=y?-x:x;y^=8;G++;d=w||s&&s>=h&&v 0,0)>M;do{_ o=I[
p=O]){q=o&z^y _ q<7){A=q--&2?8:4;C=o-9&z?q["& .\$ "]:42;do{r=I[p+=C[l]-64]_!w|p
==w){g=q|p+a-S?0:I+S _!r&(q|A<3||g)||(r+1&z^y)>9&&q|A>2){_ m=!(r-2&7))P G[1]=O,
K;J=n=o&z;E=I[p-a]&z;t=q|E-7?n:(n+=2,6^y);Z n<=t){L=r?l[r&7]*9-189-h-q:0 _ s)L
+=(1-q?l[p/x+5]-l[O/x+5]+l[p%x+6]*-~!q-l[O%x+6]+o/16*8:!!m*9)+(q?0:!(I[p-1]^n)+
!(I[p+1]^n)+l[n&7]*9-386+!!g*99+(A<2))+!(E^y^9)_ s>h||1<s&s==h&&L>z|d){p[I]=n,O
[I]=m?*g=*m,*m=0:g?*g=0:0;L-=X(s>h|d?0:p,L-N,h+1,G[1],J=q|A>1?0:p,s)_!(h||s-1|B
-O|i-n|p-b|L<-M))P y^=8,u=J;J=q-1|A<7||m||!s|d|r|o<z||v 0,0)>M;O[I]=o;p[I]=r;m?
*m=*g,*g=0:g?*g=9^y:0;}_ L>N){*G=O _ s>1){_ h&&c-L<0)P L _!h)i=n,B=O,b=p;}N=L;}
n+=J||(g=I+p,m=p<O?g-3:g+2,*m<z|m[O-p]||I[p+=p-O]);}}}}Z!r&q>2||(p=O,q|A>2|o>z&
!r&&++C*--A));}}}Z++O>98?O=20:e-O);P N+M*M&&N>-K+1924|d?N:0;}main(){Z++B<121)*G
++=B/x%x<2|B%x<2?7:B/x&4?0:*l++&31;Z B=19){Z B++<99)putchar(B%x?l[B[I]|16]:x)_
x-(B=F)){i=I[B+=(x-F)*x]&z;b=F;b+=(x-F)*x;Z x-(*G=F))i=*G^8^y;}else v u,5);v u,
1);}}
That is (or at least is an excerpt of) a chess engine.
#define _ -F<00||--F-OO--;
int F=00,OO=00;main(){F_OO();printf("%1.3f\n",4.*-F/OO/OO);}F_OO()
{
_-_-_-_
_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_-_-_-_-_
_-_-_-_-_-_-_-_
_-_-_-_
}
The above calculates pi by examination of its own area.
dporowski on
• Moderator mod
"Hey Echo, can you check out this customer's javascript?"
*goes to BDSM site during work hours*
Echo wrote: »
Let they who have not posted about their balls in the wrong thread cast the first stone.
• How you doin'? Registered User regular
TelMarine wrote: »
bowen wrote: »
Oh you saw the 6 level deep ternary I used the other day then?
I sometimes feel like people take "concise" way too far and forget about readability.
I was not proud of it but I wanted to do it just because
not a doctor, not a lawyer, examples I use may not be fully researched so don't take out of context plz, don't @ me
• sword criminal mad onlineRegistered User regular
this is a shot in a million, but in MSSQL Server, has anyone ever heard of a situation where an MSSQL Server database could fail to properly execute a stored procedure due to the weight of the parameters sent to the procedure, and do so without any apparent error?
We've got a legacy stack that stores images in an MSSQL instance, and about one in a thousand or so times, the images will fail to record (it will just make an empty row with a primary key and no other data)
We've put NUMEROUS layers of "make sure these images exist, have bytes, etc" between the client application and the database, but we still get occasional random empty rows
• Registered User regular
int median(int a, int b, int c) {
return (a<b) ? (b<c) ? b : (a<c) ? c : a : (a<c) ? a : (b<c) ? c : b;
}
Hail Hydra?
• Heretic Registered User regular
Jasconius wrote: »
this is a shot in a million, but in MSSQL Server, has anyone ever heard of a situation where an MSSQL Server database could fail to properly execute a stored procedure due to the weight of the parameters sent to the procedure, and do so without any apparent error?
We've got a legacy stack that stores images in an MSSQL instance, and about one in a thousand or so times, the images will fail to record (it will just make an empty row with a primary key and no other data)
We've put NUMEROUS layers of "make sure these images exist, have bytes, etc" between the client application and the database, but we still get occasional random empty rows
Hmmmm, not really gonna happen at that level silently.
You sure it’s the SP actually inserting the empty row?
Play D&D 4e? :: Check out Orokos and upload your Character Builder sheet! :: Orokos Dice Roller
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• Building Planet Busters Tasting FruitRegistered User regular
dporowski wrote: »
TelMarine wrote: »
bowen wrote: »
Oh you saw the 6 level deep ternary I used the other day then?
I sometimes feel like people take "concise" way too far and forget about readability.
I feel a mention of https://en.wikipedia.org/wiki/Obfuscated_Perl_Contest is topical.
Insert obligatory "isn't all Perl obfuscated?" joke
• Registered User regular
Phyphor wrote: »
dporowski wrote: »
TelMarine wrote: »
bowen wrote: »
Oh you saw the 6 level deep ternary I used the other day then?
I sometimes feel like people take "concise" way too far and forget about readability.
I feel a mention of https://en.wikipedia.org/wiki/Obfuscated_Perl_Contest is topical.
Insert obligatory "isn't all Perl obfuscated?" joke
The exact quote is: "The only language that looks the same before and after RSA encryption."
• Hard to miss. Registered User regular
I'm working with software that uses the ugliest possible code conventions:
define('Sensors'
, [
'Sensors.DataExtractor'
, 'SC.Configuration'
, 'jQuery'
, 'underscore'
, 'Backbone'
]
, function (
SensorsDataExtractor
, Configuration
, jQuery
, _
, Backbone
)
{
// code goes here
});
I believe this is called "i care more about clean git commits than readable code"...
• Moderator mod
MY EYES
That's one of those teeny things I like about Go, it actually requires a trailing comma on the last item in a multi-line array/whatever.
things = [
a,
b,
c,
]
Echo wrote: »
Let they who have not posted about their balls in the wrong thread cast the first stone.
• sword criminal mad onlineRegistered User regular
Infidel wrote: »
Jasconius wrote: »
this is a shot in a million, but in MSSQL Server, has anyone ever heard of a situation where an MSSQL Server database could fail to properly execute a stored procedure due to the weight of the parameters sent to the procedure, and do so without any apparent error?
We've got a legacy stack that stores images in an MSSQL instance, and about one in a thousand or so times, the images will fail to record (it will just make an empty row with a primary key and no other data)
We've put NUMEROUS layers of "make sure these images exist, have bytes, etc" between the client application and the database, but we still get occasional random empty rows
Hmmmm, not really gonna happen at that level silently.
You sure it’s the SP actually inserting the empty row?
We are reasonably certain, because the table also contains other data, which is consistent and traceable. We know this data comes from our users, and there is only one way our users can interact with this server.
In addition to the numerous checks on the client application which sends the images over, on the ASP.NET code that actually calls the SP, we've written a check which verifies that the param is in fact not null and has bytes at the exact moment prior to calling the SP
and yet, every so often, we see rows where these columns end up NULL
• Registered User regular
Someone's made a 3d engine in pure CSS. (yes, just CSS, no JS or anything. It works much the way you'd expect, except that he put a bunch of extra effort into get lightmaps and shadows to work, and it looks a lot more impressive as a result):
https://keithclark.co.uk/labs/css-fps/nojs/
• screaming Registered User regular
edited February 2019
It stutters a bit at first in Firefox, but otherwise seems to run smoothly.
For a good laugh, check it out in Edge.
DisruptedCapitalist on
• Borb Enthusiast flapflapflapflapRegistered User regular
If I'm not mistaken, that was made in 2013. And Edge still handles it terribly.
• How you doin'? Registered User regular
I want to say edge handles it better than firefox
firefox is technically correct but it runs like utter ass
edge runs fine it just doesn't support some very unused CSS texture mapping that breaks it
not a doctor, not a lawyer, examples I use may not be fully researched so don't take out of context plz, don't @ me
• Registered User regular
Well, let the grind begin. I am reading The Algorithm Design Manual by Skiena currently. Anyone have any interview study tips for someone looking to work for a company that starts with G and rhymes with frugal?
I expect this will take me a few months before I'm ready. Current plan is to make it through Skiena and possibly pick up Crack the Coding Interview. My initial goal is to be able to do leetcode hards in 45 minutes, possibly cut it down to 30 minutes if I can.
Steam: Spawnbroker
• A collection of mediocre hats Seattle, WARegistered User regular
bowen wrote: »
I want to say edge handles it better than firefox
firefox is technically correct but it runs like utter ass
edge runs fine it just doesn't support some very unused CSS texture mapping that breaks it
Oh wow. I just assumed that's how it was, because lol CSS. But, yes, it runs much smoother in Chrome than Firefox.
Cmon Firefox, you need to step it up a notch!
"I resent the entire notion of a body as an ante and then raise you a generalized dissatisfaction with physicality itself" -- Tycho
• Registered User regular
I'm only just getting into programming, partly because my boss left. He built our web tools and now I'm the only one left in my department. So I'm frantically trying to figure stuff out. It's good in a way because I've been wanting to learn to program, but his way was pretty old school - the most recent web app was built with VB and ASP and it uses frames - and I don't particularly want to put my efforts into learning older tech. But I have to to keep stuff running!
Anyway, I found a function in the DAO.vb file (which I guess is what ends up in the DLL?) that I need to make a minor change to, but I don't want to deploy the whole solution to the web server because I have no idea if it had any undeployed changes that would break things.
(I should also mention he didn't use source control OR a test server. I've created a test site and am seeing about versioning)
Anyway, all I want to do is get the minor change out to the server by itself. Is there a way to do that? You can't seem to right-click > publish (I'm using Visual Studio) like you can with the asp files. I tried to build and then just drop the DLL over the old DLL on the server (on the test one, mind), but no dice.
I'm sure it's something very easy and obvious but I just don't have the knowledge structure/building blocks to understand it yet.
Thanks!
• How you doin'? Registered User regular
If it's old ASP you have to deal with IIS stuff to redeploy it I think. Restarting IIS sometimes does what you need it to do I think.
not a doctor, not a lawyer, examples I use may not be fully researched so don't take out of context plz, don't @ me
• Registered User regular
bowen wrote: »
If it's old ASP you have to deal with IIS stuff to redeploy it I think. Restarting IIS sometimes does what you need it to do I think.
IIS restart should indeed do what you want once you've got the DLL in the right place.
With regards to the unknown amount of undeployed changes that could screw with things, you might want to look into the testing technique known as Golden Master. It's a bit of a ball ache and time consuming to run, but it's your best bet at testing legacy code. Especially since you have no versioning available.
• Registered User regular
I don't know how to tell if it's old SAP or not, but I can say that I've deployed the whole project on the test server and it worked okay and my changes were reflected, I just don't want to do it on the live server that way because of the aforementioned chance of untested changes that were being made.
Or maybe I'm misreading and you mean if I manually drop the DLL out there I'll need to restart the IIS?
I'll give that Golden Master a google and see what it's about, thanks!
I also noticed there is an option in VS where I can right-click and "replace file with server version" so I could probably just do that to the ASP files and be pretty safe if it works as it sounds.
• British ColumbiaRegistered User regular
edited February 2019
So this is more macro construction than programming, but man am I happy with the kludged together thing I just built in LaTeX.
I'm building a "State of the Art" survey for my research, and there are a few requirements.
1: I need a table that has all of the systems that I survey examined in the taxonomy that I'm creating.
2: Those systems should be numbered, so that I can reference them elsewhere in the text.
3: I need a way of noting when I'm referencing the systems from the table that's distinct from a normal citation (e.g. saying "The system seen in x (# on the table)")
The way that a colleague of mine did it was to have the system number circled, so that it's easy to tell when I'm referencing a system that's on the table.
So because I hate doing the tiny stuff like cross-checking the number of the system to make sure that I'm referencing correctly, I wanted something that would:
1: Automatically keep track of each system's row number in the table.
2: Be able to reference that number elsewhere in the document
3: Not be a pain in the ass to use.
The end result is like 12 macros linked together where I just need to type in "\tableref{Title}{RefTitle}", where the reftitle is the more easily-referenced title (e.g. "Full Name of System" might be shortened to "Sys"). The \tableref macro uses a different circle-drawing macro that uses the normal \ref command with the keyword to reference the output of the macro that the table runs that references the built-in row-counting macro. It's a horribly beautiful mess of stuff
It's going to hopefully save at least the hour and a half that I spent making it.
Khavall on
• A collection of mediocre hats Seattle, WARegistered User regular
edited February 2019
I have very fond memories of carefully crafting math homework LaTex files in college, because my whole life every math homework I've ever turned in has been barely readable chickenscratch, but I found LaTex and xypic and now LOOK HOW BEAUTIFUL THE MATH IS, EVERYONE HAIL OUR FEARLESS LEADER DONALD KNUTH.
Monkey Ball Warrior on
"I resent the entire notion of a body as an ante and then raise you a generalized dissatisfaction with physicality itself" -- Tycho
• He/Him | Warning: Mothership Reporting Kennewick, WARegistered User regular
I have very fond memories of carefully crafting math homework LaTex files in college, because my whole life every math homework I've ever turned in has been barely readable chickenscratch, but I found LaTex and xypic and now LOOK HOW BEAUTIFUL THE MATH IS, EVERYONE HAIL OUR FEARLESS LEADER DONALD KNUTH.
I did my Algorithms and AI classes with Word's equation tool. Probably should've learned LaTex instead :\
Steam: stabbitystyle | uPlay: stabbitystyle | b.net: Stabbity#1528 | XBL: Stabbity Style | PSN: Stabbity_Style | Twitch: stabbitystyle
• A collection of mediocre hats Seattle, WARegistered User regular
edited February 2019
I have very fond memories of carefully crafting math homework LaTex files in college, because my whole life every math homework I've ever turned in has been barely readable chickenscratch, but I found LaTex and xypic and now LOOK HOW BEAUTIFUL THE MATH IS, EVERYONE HAIL OUR FEARLESS LEADER DONALD KNUTH.
I did my Algorithms and AI classes with Word's equation tool. Probably should've learned LaTex instead :\
Earlier on I did that as well. It will do quite well in a pinch. But later my linear algebra prof introduced me to LaTeX and I never looked back.
Monkey Ball Warrior on
"I resent the entire notion of a body as an ante and then raise you a generalized dissatisfaction with physicality itself" -- Tycho
This discussion has been closed. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.1747109293937683, "perplexity": 4358.587968078078}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-31/segments/1627046153971.20/warc/CC-MAIN-20210730154005-20210730184005-00367.warc.gz"} |
https://brilliant.org/discussions/thread/worse-than-a-continued-fraction/ | ×
# Worse than a continued fraction
Compute the result of the following:
$1 + \cfrac{2 + \cfrac{4 + \cfrac{8 + \ldots}{12 + \ldots}}{6 + \cfrac{12 + \ldots}{18 + \ldots}}}{3 + \cfrac{6 + \cfrac{12 + \ldots}{18 + \ldots}}{9 + \cfrac{18 + \ldots}{27 + \ldots}}}$
Informally, you have something like $$f(x) = x + \frac{f(2x)}{f(3x)}$$ for all $$x$$; expand $$f(1)$$ to infinity and compute its result.
(Note that I don't know the result; if I knew, I would have made this a problem. Source: friend's tweet)
Note by Ivan Koswara
1 year, 6 months ago
Sort by:
Intuitively it would seem like $$f(x)$$ is an increasing function. Rearranging the recursive function gives $$f(3x)(f(x)-x)=f(2x)$$ so $$|f(x)-x| < 1$$. That would imply that $$f(x)$$ increases approximately linearly, but then again plugging in $$f(x)=x+c$$ gives no solution. · 1 year, 6 months ago
The solution to $$c$$ in $f(3x)(f(x)-x)=f(2x)$ where $$f(x)=\sqrt[n]{x^n+c}$$ as $$n\to \infty$$ and $$x=1$$ appears to be unbounded, so this path seems to be a dead end. Of course, all the math I'm doing is pretty hand-wavy to begin with. · 1 year, 6 months ago
An amazing idea !! · 1 year, 6 months ago
The answer is definitely $$\frac{5}{3}$$. Here's as far as I've gotten in proving it:
If you follow the fraction backward far enough you'll begin to realize that the terms inside the biggest parentheses tend towards $$1$$ as the fraction expands to infinity. This gives $$1+\frac{2}{3}=\frac{5}{3}$$, but this isn't exactly a proof, more a heuristic argument. · 1 year, 6 months ago
that's what I thought initially. However, if you track the fractions, you are not correctly removing the factors of 2 and 3. Staff · 1 year, 6 months ago
This problem really intrigues me, it seems so simple to state yet so hard to prove! · 1 year, 6 months ago
This is definetly a mind bender · 1 year, 6 months ago
Well...
The answer is definitely $$\frac{5}{3}$$.
this isn't exactly a proof, more a heuristic argument.
I think they are quite contradictory.
I'm also pretty confident the answer is much closer to the one found by iteration (slightly less than $$\sqrt{3}$$) than $$\frac{5}{3}$$. Intuitively (not yet proven!), any of the fractions has value lying in $$(0, 1)$$. You can thus bound the result by replacing fractions to deep in the iteration with one of the two extreme values appropriately:
\begin{align*} &1 + \cfrac{2 + \cfrac{4 + 0}{6 + 1}}{3 + \cfrac{6 + 1}{9 + 0}} = \frac{200}{119} \approx 1.6806722 \\ \le &1 + \cfrac{2 + \cfrac{4 + \ldots}{6 + \ldots}}{3 + \cfrac{6 + \ldots}{9 + \ldots}} \\ \le &1 + \cfrac{2 + \cfrac{4 + 1}{6 + 0}}{3 + \cfrac{6 + 0}{9 + 1}} = \frac{193}{108} \approx 1.7870370 \end{align*} · 1 year, 6 months ago
Some code to compute with different starting values and iteration depth: here
It's interesting to see that things converge quickly and that it is indeed approximately linear. · 1 year, 6 months ago
In fact, for large $$x$$, we have $$f(x) \to x + \frac{2}{3}$$ (as expected?). · 1 year, 6 months ago | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9948673248291016, "perplexity": 1027.501298749982}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-04/segments/1484560280310.48/warc/CC-MAIN-20170116095120-00013-ip-10-171-10-70.ec2.internal.warc.gz"} |
http://jdh.hamkins.org/tag/surreal-numbers/ | # The hypnagogic digraph, with applications to embeddings of the set-theoretic universe, JMM Special Session on Surreal Numbers, Seattle, January 2016
This will be an invited talk for the AMS-ASL special session on Surreal Numbers at the 2016 Joint Mathematics Meetings in Seattle, Washington, January 6-9, 2016.
Abstract. The hypnagogic digraph, a proper-class analogue of the countable random $\mathbb{Q}$-graded digraph, is a surreal-numbers-graded acyclic digraph exhibiting the set-pattern property (a form of existential-closure), making it set-homogeneous and universal for all class acyclic digraphs. A natural copy of this canonical structure arises during the course of the usual construction of the surreal number line, using as vertices the surreal-number numerals $\{\ A \mid B\ \}$. I shall explain the construction and elementary theory of the hypnagogic digraph and describe recent uses of it in connection with embeddings of the set-theoretic universe, such as in the proof that the countable models of set theory are linearly pre-ordered by embeddability.
# Universality, saturation and the surreal number line, Shanghai, June 2013
This will be a short lecture series given at the conclusion of the graduate logic class in the Mathematical Logic group at Fudan University in Shanghai, June 13, 18 (or 20), 2013.
I will present an elementary introduction to the theory of universal orders and relations and saturated structures. We’ll start with the classical fact, proved by Cantor, that the rational line is the universal countable linear order. But what about universal partial orders, universal graphs and other mathematical structures? Is there a computable universal partial order? What is the countable random graph? Which orders embed into the power set of the natural numbers under the subset relation $\langle P(\mathbb{N}),\subset\rangle$? Proceeding to larger and larger universal orders, we’ll eventually arrive at the surreal numbers and the hypnagogic digraph.
# The countable models of set theory are linearly pre-ordered by embeddability, Rutgers, November 2012
This will be a talk for the Rutgers Logic Seminar on November 19, 2012.
Abstract. I will speak on my recent theorem that every countable model of set theory $M$, including every well-founded model, is isomorphic to a submodel of its own constructible universe. In other words, there is an embedding $j:M\to L^M$ that is elementary for quantifier-free assertions. The proof uses universal digraph combinatorics, including an acyclic version of the countable random digraph, which I call the countable random $\mathbb{Q}$-graded digraph, and higher analogues arising as uncountable Fraisse limits, leading to the hypnagogic digraph, a set-homogeneous, class-universal, surreal-numbers-graded acyclic class digraph, closely connected with the surreal numbers. The proof shows that $L^M$ contains a submodel that is a universal acyclic digraph of rank $\text{Ord}^M$. The method of proof also establishes that the countable models of set theory are linearly pre-ordered by embeddability: for any two countable models of set theory, one of them is isomorphic to a submodel of the other. Indeed, the bi-embeddability classes form a well-ordered chain of length $\omega_1+1$. Specifically, the countable well-founded models are ordered by embeddability in accordance with the heights of their ordinals; every shorter model embeds into every taller model; every model of set theory $M$ is universal for all countable well-founded binary relations of rank at most $\text{Ord}^M$; and every ill-founded model of set theory is universal for all countable acyclic binary relations. Finally, strengthening a classical theorem of Ressayre, the same proof method shows that if $M$ is any nonstandard model of PA, then every countable model of set theory—in particular, every model of ZFC—is isomorphic to a submodel of the hereditarily finite sets $HF^M$ of $M$. Indeed, $HF^M$ is universal for all countable acyclic binary relations. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8927300572395325, "perplexity": 713.4692920232994}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610704799711.94/warc/CC-MAIN-20210126073722-20210126103722-00300.warc.gz"} |
https://math.stackexchange.com/questions/2396257/asymptotic-form-of-coefficients-of-a-given-generating-function | # Asymptotic form of coefficients of a given generating function
Suppose I know that the generating function of some sequence $(f_n)_n$ is $$G(f_n;x) = \exp\left[-\alpha\cdot\arcsin(\beta\cdot x)+\frac{1}{2}\log\left(\gamma\sqrt{1-\delta \cdot x^2}+1-\delta \cdot x\right)\right]$$ for some constants $\alpha,\beta,\gamma,\delta$. How can one deduce the asymptotic formula of the coefficients corresponding to the above generating function?
It seems that usual techniques involving Tauberian theorem, or the "Asymptotic growth of a sequence" section in
https://en.wikipedia.org/wiki/Generating_function
are not so helpful. Is there any way to do that?
• The standard answer for this is "check Flajolet and Sedgwick", although I don't know if that would actually be helpful in this case. – Michael Lugo Aug 17 '17 at 14:55 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9750664830207825, "perplexity": 284.3427524456744}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-26/segments/1560628000306.84/warc/CC-MAIN-20190626114215-20190626140215-00097.warc.gz"} |
https://worldwidescience.org/topicpages/r/reference+frame+independent.html | #### Sample records for reference frame independent
1. Reference-Frame-Independent and Measurement-Device-Independent Quantum Key Distribution Using One Single Source
Science.gov (United States)
Li, Qian; Zhu, Changhua; Ma, Shuquan; Wei, Kejin; Pei, Changxing
2018-04-01
Measurement-device-independent quantum key distribution (MDI-QKD) is immune to all detector side-channel attacks. However, practical implementations of MDI-QKD, which require two-photon interferences from separated independent single-photon sources and a nontrivial reference alignment procedure, are still challenging with current technologies. Here, we propose a scheme that significantly reduces the experimental complexity of two-photon interferences and eliminates reference frame alignment by the combination of plug-and-play and reference frame independent MDI-QKD. Simulation results show that the secure communication distance can be up to 219 km in the finite-data case and the scheme has good potential for practical MDI-QKD systems.
2. Phase-encoded measurement device independent quantum key distribution without a shared reference frame
Science.gov (United States)
Zhuo-Dan, Zhu; Shang-Hong, Zhao; Chen, Dong; Ying, Sun
2018-07-01
In this paper, a phase-encoded measurement device independent quantum key distribution (MDI-QKD) protocol without a shared reference frame is presented, which can generate secure keys between two parties while the quantum channel or interferometer introduces an unknown and slowly time-varying phase. The corresponding secret key rate and single photons bit error rate is analysed, respectively, with single photons source (SPS) and weak coherent source (WCS), taking finite-key analysis into account. The numerical simulations show that the modified phase-encoded MDI-QKD protocol has apparent superiority both in maximal secure transmission distance and key generation rate while possessing the improved robustness and practical security in the high-speed case. Moreover, the rejection of the frame-calibrating part will intrinsically reduce the consumption of resources as well as the potential security flaws of practical MDI-QKD systems.
3. Device-dependent and device-independent quantum key distribution without a shared reference frame
International Nuclear Information System (INIS)
Slater, Joshua A; Tittel, Wolfgang; Branciard, Cyril; Brunner, Nicolas
2014-01-01
Standard quantum key distribution (QKD) protocols typically assume that the distant parties share a common reference frame. In practice, however, establishing and maintaining a good alignment between distant observers is rarely a trivial issue, which may significantly restrain the implementation of long-distance quantum communication protocols. Here we propose simple QKD protocols that do not require the parties to share any reference frame, and study their security and feasibility in both the usual device-dependent (DD) case—in which the two parties use well characterized measurement devices—as well as in the device-independent (DI) case—in which the measurement devices can be untrusted, and the security relies on the violation of a Bell inequality. To illustrate the practical relevance of these ideas, we present a proof-of-principle demonstration of our protocols using polarization entangled photons distributed over a coiled 10-km long optical fiber. We consider two situations, in which either the fiber spool's polarization transformation freely drifts, or randomly chosen polarization transformations are applied. The correlations obtained from measurements allow, with high probability, to generate positive asymptotic secret key rates in both the DD and DI scenarios (under the fair-sampling assumption for the latter case). (paper)
4. Demonstration of free-space reference frame independent quantum key distribution
International Nuclear Information System (INIS)
Wabnig, J; Bitauld, D; Li, H W; Niskanen, A O; Laing, A; O'Brien, J L
2013-01-01
Quantum key distribution (QKD) is moving from research laboratories towards applications. As computing becomes more mobile, cashless as well as cardless payment solutions are introduced. A possible route to increase the security of wireless communications is to incorporate QKD in a mobile device. Handheld devices present a particular challenge as the orientation and the phase of a qubit will depend on device motion. This problem is addressed by the reference frame independent (RFI) QKD scheme. The scheme tolerates an unknown phase between logical states that vary slowly compared to the rate of particle repetition. Here we experimentally demonstrate the feasibility of RFI QKD over a free-space link in a prepare and measure scheme using polarization encoding. We extend the security analysis of the RFI QKD scheme to be able to deal with uncalibrated devices and a finite number of measurements. Together these advances are an important step towards mass production of handheld QKD devices. (paper)
5. Effector-independent motor sequence representations exist in extrinsic and intrinsic reference frames.
Science.gov (United States)
Wiestler, Tobias; Waters-Metenier, Sheena; Diedrichsen, Jörn
2014-04-02
Many daily activities rely on the ability to produce meaningful sequences of movements. Motor sequences can be learned in an effector-specific fashion (such that benefits of training are restricted to the trained hand) or an effector-independent manner (meaning that learning also facilitates performance with the untrained hand). Effector-independent knowledge can be represented in extrinsic/world-centered or in intrinsic/body-centered coordinates. Here, we used functional magnetic resonance imaging (fMRI) and multivoxel pattern analysis to determine the distribution of intrinsic and extrinsic finger sequence representations across the human neocortex. Participants practiced four sequences with one hand for 4 d, and then performed these sequences during fMRI with both left and right hand. Between hands, these sequences were equivalent in extrinsic or intrinsic space, or were unrelated. In dorsal premotor cortex (PMd), we found that sequence-specific activity patterns correlated higher for extrinsic than for unrelated pairs, providing evidence for an extrinsic sequence representation. In contrast, primary sensory and motor cortices showed effector-independent representations in intrinsic space, with considerable overlap of the two reference frames in caudal PMd. These results suggest that effector-independent representations exist not only in world-centered, but also in body-centered coordinates, and that PMd may be involved in transforming sequential knowledge between the two. Moreover, although effector-independent sequence representations were found bilaterally, they were stronger in the hemisphere contralateral to the trained hand. This indicates that intermanual transfer relies on motor memories that are laid down during training in both hemispheres, but preferentially draws upon sequential knowledge represented in the trained hemisphere.
6. Changing quantum reference frames
OpenAIRE
Palmer, Matthew C.; Girelli, Florian; Bartlett, Stephen D.
2013-01-01
We consider the process of changing reference frames in the case where the reference frames are quantum systems. We find that, as part of this process, decoherence is necessarily induced on any quantum system described relative to these frames. We explore this process with examples involving reference frames for phase and orientation. Quantifying the effect of changing quantum reference frames serves as a first step in developing a relativity principle for theories in which all objects includ...
7. Optimal primitive reference frames
International Nuclear Information System (INIS)
Jennings, David
2011-01-01
We consider the smallest possible directional reference frames allowed and determine the best one can ever do in preserving quantum information in various scenarios. We find that for the preservation of a single spin state, two orthogonal spins are optimal primitive reference frames; and in a product state, they do approximately 22% as well as an infinite-sized classical frame. By adding a small amount of entanglement to the reference frame, this can be raised to 2(2/3) 5 =26%. Under the different criterion of entanglement preservation, a very similar optimal reference frame is found; however, this time it is for spins aligned at an optimal angle of 87 deg. In this case 24% of the negativity is preserved. The classical limit is considered numerically, and indicates under the criterion of entanglement preservation, that 90 deg. is selected out nonmonotonically, with a peak optimal angle of 96.5 deg. for L=3 spins.
8. Frames of Reference'' revisited
Science.gov (United States)
Steyn-Ross, Alistair; Ivey, Donald G.
1992-12-01
The PSSC teaching film, Frames of Reference,'' was made in 1960, and was one of the first audio-visual attempts at showing how your physical point of view,'' or frame of reference, necessarily alters both your perceptions and your observations of motion. The gentle humor and original demonstrations made a lasting impact on many audiences, and with its recent re-release as part of the AAPT Cinema Classics videodisc it is timely that we should review both the message and the methods of the film. An annotated script and photographs from the film are presented, followed by extension material on rotating frames which teachers may find appropriate for use in their classrooms: constructions, demonstrations, an example, and theory.
9. Quantum frames of reference
International Nuclear Information System (INIS)
Kaufherr, T.
1981-01-01
The idea that only relative variables have physical meaning came to be known as Mach's principle. Carrying over this idea to quantum theory, has led to the consideration of finite mass, macroscopic reference frames, relative to which all physical quantities are measured. During the process of measurement, a finite mass observer receives a kickback, and this reaction of the measuring device is not negligible in quantum theory because of the quantization of the action. Hence, the observer himself has to be included in the system that is being considered. Using this as the starting point, a number of thought experiments involving finite mass observers is discussed which have quantum uncertainties in their time or in their position. These thought experiments serve to elucidate in a qualitative way some of the difficulties involved, as well as pointing out a direction to take in seeking solutions to them. When the discussion is extended to include more than one observer, the question of the covariance of the theory immediately arises. Because none of the frames of reference should be preferred, the theory should be covariant. This demand expresses an equivalence principle which here is extended to include reference frames which are in quantum uncertainties relative to each other. Formulating the problem in terms of canonical variables, the ensueing free Hamiltonian contains vector and scalar potentials which represent the kick that the reference frame receives during measurement. These are essentially gravitational type potentials, resulting, as it were, from the extension of the equivalence principle into the quantum domain
10. Balinese Frame of Reference
Directory of Open Access Journals (Sweden)
I Nyoman Aryawibawa
2016-04-01
Full Text Available Abstract: Balinese Frame of Reference. Wassmann and Dasen (1998 did a study on the acquisition of Balinese frames of reference. They pointed out that, in addition to the dominant use of absolute system, the use of relative system was also observed. This article aims at verifying Wassmann and Dasen’ study. Employing monolingual Balinese speakers and using linguistic and non-linguistic tasks, Aryawibawa (2010, 2012, 2015 showed that Balinese subjects used an absolute system dominantly in responding the two tasks, e.g. The man is north/south/east/west of the car. Unlike Wassmann and Dasen’s results, no relative system was used by the subjects in solving the tasks. Instead of the relative system, an intrinsic system was also observed in this study, even though it was unfrequent. The article concludes that the absolute system was dominantly employed by Balinese speakers in describing spatial relations in Balinese. The use of the system seems to affect their cognitive functions.
11. Global Vertical Reference Frame
Czech Academy of Sciences Publication Activity Database
Burša, Milan; Kenyon, S.; Kouba, J.; Šíma, Zdislav; Vatrt, V.; Vojtíšková, M.
2004-01-01
Roč. 33, - (2004), s. 404-407 ISSN 1436-3445 Institutional research plan: CEZ:AV0Z1003909 Keywords : geopotential WO * vertical systems * global vertical frame Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics
12. Global Vertical Reference Frame
Czech Academy of Sciences Publication Activity Database
Burša, Milan; Kenyon, S.; Kouba, J.; Šíma, Zdislav; Vatrt, V.; Vojtíšková, M.
-, č. 5 (2009), s. 53-63 ISSN 1801-8483 R&D Projects: GA ČR GA205/08/0328 Institutional research plan: CEZ:AV0Z10030501 Keywords : sea surface topography * satellite altimetry * vertical frames Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics
13. Reference frame for Product Configuration
DEFF Research Database (Denmark)
Ladeby, Klaes Rohde; Oddsson, Gudmundur Valur
2011-01-01
a reference frame for configuration that permits 1) a more precise understanding of a configuration system, 2) a understanding of how the configuration system relate to other systems, and 3) a definition of the basic concepts in configuration. The total configuration system, together with the definition...
14. Postural adaptation of the spatial reference frames to microgravity: back to the egocentric reference frame.
Directory of Open Access Journals (Sweden)
Sébastien Viel
Full Text Available BACKGROUND: In order to test how gravitational information would affect the choice of stable reference frame used to control posture and voluntary movement, we have analysed the forearm stabilisation during sit to stand movement under microgravity condition obtained during parabolic flights. In this study, we hypothesised that in response to the transient loss of graviceptive information, the postural adaptation might involve the use of several strategies of segmental stabilisation, depending on the subject's perceptual typology (dependence--independence with respect to the visual field. More precisely, we expected a continuum of postural strategies across subjects with 1 at one extreme the maintaining of an egocentric reference frame and 2 at the other the re-activation of childhood strategies consisting in adopting an egocentric reference frame. METHODOLOGY/PRINCIPAL FINDINGS: To check this point, a forearm stabilisation task combined with a sit to stand movement was performed with eyes closed by 11 subjects during parabolic flight campaigns. Kinematic data were collected during 1-g and 0-g periods. The postural adaptation to microgravity's constraint may be described as a continuum of strategies ranging from the use of an exo- to an egocentric reference frame for segmental stabilisation. At one extremity, the subjects used systematically an exocentric frame to control each of their body segments independently, as under normogravity conditions. At the other, the segmental stabilisation strategies consist in systematically adopting an egocentric reference frame to control their forearm's stabilisation. A strong correlation between the mode of segmental stabilisation used and the perceptual typology (dependence--independence with respect to the visual field of the subjects was reported. CONCLUSION: The results of this study show different subjects' typologies from those that use the forearm orientation in a mainly exocentric reference frame to
15. Connecting VLBI and Gaia Celestial Reference Frames
Energy Technology Data Exchange (ETDEWEB)
Malkin, Zinovy, E-mail: malkin@gao.spb.ru [Department of Radio Astronomy Research, The Pulkovo Astronomical Observatory, St. Petersburg (Russian Federation); Institute of Earth Sciences, St. Petersburg State University, St. Petersburg (Russian Federation); Astronomy and Cosmic Geodesy Department, Kazan Federal University, Kazan (Russian Federation)
2016-09-12
16. Connecting VLBI and Gaia celestial reference frames
Directory of Open Access Journals (Sweden)
Zinovy Malkin
2016-09-01
Full Text Available The current state of the link problem between radio and optical celestial reference frames is considered.The main objectives of the investigations in this direction during the next few years are the preparation of a comparisonand the mutual orientation and rotation between the optical it Gaia Celestial Reference Frame (GCRFand the 3rd generation radio International Celestial Reference Frame (ICRF3, obtained from VLBI observations.Both systems, ideally, should be a realization of the ICRS (International Celestial Reference System at micro-arcsecond level accuracy.Therefore, the link accuracy between the ICRF and GCRF should be obtained with similar error level, which is not a trivial taskdue to relatively large systematic and random errors in source positions at different frequency bands.In this paper, a brief overview of recent work on the GCRF--ICRF link is presented.Additional possibilities to improve the GCRF--ICRF link accuracy are discussed.The suggestion is made to use astrometric radio sources with optical magnitude to 20$^m$ rather than to 18$^m$ as currently plannedfor the GCRF--ICRF link.In addition, the use of radio stars is also a prospective method to obtain independent and accurate orientation between the Gaia frame and the ICRF.
17. Inertial reference frames and gravitational forces
International Nuclear Information System (INIS)
Santavy, I.
1981-01-01
The connection between different definitions of inertial, i.e. fundamental, reference frames and the corresponding characterisation of gravitational fields by gravitational forces are considered from the point of view of their possible interpretation in university introductory courses. The introduction of a special class of reference frames, denoted 'mixed reference frames' is proposed and discussed. (author)
18. Common Frame of Reference and social justice
NARCIS (Netherlands)
2009-01-01
The article "Common Frame of Reference and Social Justice" by Martijn W. Hesselink evaluates the Draft Common Frame of Reference (DCFR) of social justice. It discusses the important areas, namely a common frame of Reference in a broad sense, social justice and contract law, private law and
19. Mercury's Reference Frames After the MESSENGER Mission
Science.gov (United States)
Stark, A.; Oberst, J.; Preusker, F.; Burmeister, S.; Steinbrügge, G.; Hussmann, H.
2018-05-01
We provide an overview of Mercury's reference frames based on MESSENGER observations. We discuss the dynamical, the principal-axes, the ellipsoid, as well as the cartographic frame, which was adopted for MESSENGER data products.
20. Mechanical Energy Change in Inertial Reference Frames
Science.gov (United States)
Ghanbari, Saeed
2016-01-01
The mechanical energy change of a system in an inertial frame of reference equals work done by the total nonconservative force in the same frame. This relation is covariant under the Galilean transformations from inertial frame S to S', where S' moves with constant velocity relative to S. In the presence of nonconservative forces, such as normal…
1. Quantum communication, reference frames, and gauge theory
International Nuclear Information System (INIS)
Enk, S. J. van
2006-01-01
We consider quantum communication in the case that the communicating parties not only do not share a reference frame but use imperfect quantum communication channels, in that each channel applies some fixed but unknown unitary rotation to each qubit. We discuss similarities and differences between reference frames within that quantum communication model and gauge fields in gauge theory. We generalize the concept of refbits and analyze various quantum communication protocols within the communication model
2. Quantum bit commitment with misaligned reference frames
International Nuclear Information System (INIS)
Harrow, Aram; Oliveira, Roberto; Terhal, Barbara M.
2006-01-01
Suppose that Alice and Bob define their coordinate axes differently, and the change of reference frame between them is given by a probability distribution μ over SO(3). We show that this uncertainty of reference frame is of no use for bit commitment when μ is uniformly distributed over a (sub)group of SO(3), but other choices of μ can give rise to a partially or even arbitrarily secure bit commitment
3. Physics of Non-Inertial Reference Frames
International Nuclear Information System (INIS)
Kamalov, Timur F.
2010-01-01
Physics of non-inertial reference frames is a generalizing of Newton's laws to any reference frames. It is the system of general axioms for classical and quantum mechanics. The first, Kinematics Principle reads: the kinematic state of a body free of forces conserves and equal in absolute value to an invariant of the observer's reference frame. The second, Dynamics Principle extended Newton's second law to non-inertial reference frames and also contains additional variables there are higher derivatives of coordinates. Dynamics Principle reads: a force induces a change in the kinematic state of the body and is proportional to the rate of its change. It is mean that if the kinematic invariant of the reference frame is n-th derivative with respect the time, then the dynamics of a body being affected by the force F is described by the 2n-th differential equation. The third, Statics Principle reads: the sum of all forces acting a body at rest is equal to zero.
4. On Translators' Cultural Frame of Functionist Reference
Science.gov (United States)
Fu, Zhiyi
2009-01-01
A deep cognition with translators' cultural frame of functionist reference can help instructors and teachers adjust and extend patterns and schemes of translation and generate the optimal classroom conditions for acquisition of the target language. The author of the paper, in the perspectives of motivational, cognitive and communicative…
5. Common Frame of Reference & social justice
NARCIS (Netherlands)
2008-01-01
This paper evaluates the draft Common Frame of Reference (DCFR) in terms of social justice. It concludes the DCFR has all the characteristics of a typical European compromise. Ideological and esthetical purists will certainly be disappointed. In this respect, it has much in common with the
6. Frames of reference in spatial language acquisition.
Science.gov (United States)
Shusterman, Anna; Li, Peggy
2016-08-01
7. Integration of Reference Frames Using VLBI
Science.gov (United States)
Ma, Chopo; Smith, David E. (Technical Monitor)
2001-01-01
Very Long Baseline Interferometry (VLBI) has the unique potential to integrate the terrestrial and celestial reference frames through simultaneous estimation of positions and velocities of approx. 40 active VLBI stations and a similar number of stations/sites with sufficient historical data, the position and position stability of approx. 150 well-observed extragalactic radio sources and another approx. 500 sources distributed fairly uniformly on the sky, and the time series of the five parameters that specify the relative orientation of the two frames. The full realization of this potential is limited by a number of factors including the temporal and spatial distribution of the stations, uneven distribution of observations over the sources and the sky, variations in source structure, modeling of the solid/fluid Earth and troposphere, logistical restrictions on the daily observing network size, and differing strategies for optimizing analysis for TRF, for CRF and for EOP. The current status of separately optimized and integrated VLBI analysis will be discussed.
8. Generalized frame of reference with null congruence
International Nuclear Information System (INIS)
Ferrarese, G.; Antonelli, R.
2000-01-01
The paper derives the main properties of a generalized frame of reference with a null congruence (light flux), by means of adapted non-holonomic techniques; then it studies the geometry of the space-time in terms of non-orthogonal projection: longitudinal and transverse covariant derivatives and corresponding commutation formulae, decomposition of the Riemann and gravitational tensors, lie derivatives of the Ricci rotation coefficients, transverse Bianchi identity. Application to the (absolute and relative) light flux: kinematical characteristics and screen, Sachs theorems etc. are also given
9. Transformations between inertial and linearly accelerated frames of reference
International Nuclear Information System (INIS)
Ashworth, D.G.
1983-01-01
Transformation equations between inertial and linearly accelerated frames of reference are derived and these transformation equations are shown to be compatible, where applicable, with those of special relativity. The physical nature of an accelerated frame of reference is unambiguously defined by means of an equation which relates the velocity of all points within the accelerated frame of reference to measurements made in an inertial frame of reference. (author)
10. Quantum mechanics with respect to different reference frames
International Nuclear Information System (INIS)
Mangiarotti, L.; Sardanashvily, G.
2007-01-01
Geometric (Schroedinger) quantization of nonrelativistic mechanics with respect to different reference frames is considered. In classical nonrelativistic mechanics, a reference frame is represented by a connection on a configuration space fibered over a time axis R. Under quantization, it yields a connection on the quantum algebra of Schroedinger operators. The operators of energy with respect to different reference frames are examined
11. Entanglement detection with bounded reference frames
International Nuclear Information System (INIS)
Costa, Fabio; Brukner, Caslav; Harrigan, Nicholas; Rudolph, Terry
2009-01-01
Quantum experiments usually assume the existence of perfect, classical reference frames (RFs), which allow for the specification of measurement settings (e.g. orientation of the Stern-Gerlach magnet in spin measurements) with arbitrary precision. If the RFs are 'bounded' (i.e. quantum systems themselves, having a finite number of degrees of freedom), only limited precision can be attained. Using spin coherent states as bounded RFs, we have found the minimum size needed for them to violate local realism for entangled spin systems. For composite systems of spin 1/2 particles, RFs of very small size are sufficient for the violation; however, to see this violation for macroscopic entangled spins, the size of the RF must be at least quadratically larger than that of the spins. The unavailability of such RFs gives a possible explanation for the non-observance of violation of local realism in everyday experience.
12. Quantum reference frames and quantum transformations
International Nuclear Information System (INIS)
Toller, M.
1997-01-01
A quantum frame is defined by a material object following the laws of quantum mechanics. The present paper studies the relations between quantum frames, which are described by some generalization of the Poincare' group. The possibility of using a suitable quantum group is examined, but some arguments are given which show that a different mathematical structure is necessary. Some simple examples in lower-dimensional space-times are treated. They indicate the necessity of taking into account some ''internal'' degrees of freedom of the quantum frames, that can be disregarded in a classical treatment
13. Spatial Updating Strategy Affects the Reference Frame in Path Integration.
Science.gov (United States)
He, Qiliang; McNamara, Timothy P
2018-06-01
This study investigated how spatial updating strategies affected the selection of reference frames in path integration. Participants walked an outbound path consisting of three successive waypoints in a featureless environment and then pointed to the first waypoint. We manipulated the alignment of participants' final heading at the end of the outbound path with their initial heading to examine the adopted reference frame. We assumed that the initial heading defined the principal reference direction in an allocentric reference frame. In Experiment 1, participants were instructed to use a configural updating strategy and to monitor the shape of the outbound path while they walked it. Pointing performance was best when the final heading was aligned with the initial heading, indicating the use of an allocentric reference frame. In Experiment 2, participants were instructed to use a continuous updating strategy and to keep track of the location of the first waypoint while walking the outbound path. Pointing performance was equivalent regardless of the alignment between the final and the initial headings, indicating the use of an egocentric reference frame. These results confirmed that people could employ different spatial updating strategies in path integration (Wiener, Berthoz, & Wolbers Experimental Brain Research 208(1) 61-71, 2011), and suggested that these strategies could affect the selection of the reference frame for path integration.
14. Are all spatial reference frames egocentric? Reinterpreting evidence for allocentric, object-centered, or world-centered reference frames
Directory of Open Access Journals (Sweden)
Flavia eFilimon
2015-12-01
Full Text Available The use and neural representation of egocentric spatial reference frames is well documented. In contrast, whether the brain represents spatial relationships between objects in allocentric, object-centered, or world-centered coordinates is debated. Here, I review behavioral, neuropsychological, neurophysiological (neuronal recording, and neuroimaging evidence for and against allocentric, object-centered, or world-centered spatial reference frames. Based on theoretical considerations, simulations, and empirical findings from spatial navigation, spatial judgments, and goal-directed movements, I suggest that all spatial representations may in fact be dependent on egocentric reference frames.
15. Are All Spatial Reference Frames Egocentric? Reinterpreting Evidence for Allocentric, Object-Centered, or World-Centered Reference Frames
OpenAIRE
Filimon, Flavia
2015-01-01
The use and neural representation of egocentric spatial reference frames is well-documented. In contrast, whether the brain represents spatial relationships between objects in allocentric, object-centered, or world-centered coordinates is debated. Here, I review behavioral, neuropsychological, neurophysiological (neuronal recording), and neuroimaging evidence for and against allocentric, object-centered, or world-centered spatial reference frames. Based on theoretical considerations, simulati...
16. Measuring the quality of a quantum reference frame: The relative entropy of frameness
International Nuclear Information System (INIS)
Gour, Gilad; Marvian, Iman; Spekkens, Robert W.
2009-01-01
In the absence of a reference frame for transformations associated with group G, any quantum state that is noninvariant under the action of G may serve as a token of the missing reference frame. We here present a measure of the quality of such a token: the relative entropy of frameness. This is defined as the relative entropy distance between the state of interest and the nearest G-invariant state. Unlike the relative entropy of entanglement, this quantity is straightforward to calculate, and we find it to be precisely equal to the G-asymmetry, a measure of frameness introduced by Vaccaro et al. It is shown to provide an upper bound on the mutual information between the group element encoded into the token and the group element that may be extracted from it by measurement. In this sense, it quantifies the extent to which the token successfully simulates a full reference frame. We also show that despite a suggestive analogy from entanglement theory, the regularized relative entropy of frameness is zero and therefore does not quantify the rate of interconversion between the token and some standard form of quantum reference frame. Finally, we show how these investigations yield an approach to bounding the relative entropy of entanglement.
17. Language and spatial frames of reference in mind and brain.
Science.gov (United States)
Gallistel, C R.
2002-08-01
Some language communities routinely use allocentric reference directions (e.g. 'uphill-downhill') where speakers of European languages would use egocentric references ('left-right'). Previous experiments have suggested that the different language groups use different reference frames in non-linguistic tasks involving the recreation of oriented arrays. However, a recent paper argues that manipulating test conditions produces similar effects in monolingual English speakers, and in animals.
18. Tight Reference Frame–Independent Quantum Teleportation
Directory of Open Access Journals (Sweden)
Dominic Verdon
2017-01-01
Full Text Available We give a tight scheme for teleporting a quantum state between two parties whose reference frames are misaligned by an action of a finite symmetry group. Unlike previously proposed schemes, ours requires no additional tokens or data to be passed between the participants; the same amount of classical information is transferred as for ordinary quantum teleportation, and the Hilbert space of the entangled resource is of the same size. In the terminology of Peres and Scudo, our protocol relies on classical communication of unspeakable information.
19. Overall properties of the Gaia DR1 reference frame
Science.gov (United States)
Liu, N.; Zhu, Z.; Liu, J.-C.; Ding, C.-Y.
2017-03-01
Aims: The first Gaia data release (Gaia DR1) provides 2191 ICRF2 sources with their positions in the auxiliary quasar solution and five astrometric parameters - positions, parallaxes, and proper motions - for stars in common between the Tycho-2 catalogue and Gaia in the joint Tycho-Gaia astrometric solution (TGAS). We aim to analyze the overall properties of Gaia DR1 reference frame. Methods: We compare quasar positions of the auxiliary quasar solution with ICRF2 sources using different samples and evaluate the influence on the Gaia DR1 reference frame owing to the Galactic aberration effect over the J2000.0-J2015.0 period. Then we estimate the global rotation between TGAS with Tycho-2 proper motion systems to investigate the property of the Gaia DR1 reference frame. Finally, the Galactic kinematics analysis using the K-M giant proper motions is performed to understand the property of Gaia DR1 reference frame. Results: The positional comparison between the auxiliary quasar solution and ICRF2 shows negligible orientation and validates the declination bias of -0.1mas in Gaia quasar positions with respect to ICRF2. Galactic aberration effect is thought to cause an offset 0.01mas of the Z axis direction of Gaia DR1 reference frame. The global rotation between TGAS and Tycho-2 proper motion systems, obtained by different samples, shows a much smaller value than the claimed value 0.24mas yr-1. For the Galactic kinematics analysis of the TGAS K-M giants, we find possible non-zero Galactic rotation components beyond the classical Oort constants: the rigid part ωYG = -0.38±0.15mas yr-1 and the differential part ω^primeYG = -0.29±0.19mas yr-1 around the YG axis of Galactic coordinates, which indicates possible residual rotation in Gaia DR1 reference frame or problems in the current Galactic kinematical model. Conclusions: The Gaia DR1 reference frame is well aligned to ICRF2, and the possible influence of the Galactic aberration effect should be taken into consideration
20. Perception of space by multiple intrinsic frames of reference.
Directory of Open Access Journals (Sweden)
Yanlong Sun
Full Text Available It has been documented that when memorizing a physical space, the person's mental representation of that space is biased with distortion and segmentation. Two experiments reported here suggest that distortion and segmentation arise due to a hierarchical organization of the spatial representation. The spatial relations associated with salient landmarks are more strongly encoded and easier to recall than those associated with non-salient landmarks. In the presence of multiple salient landmarks, multiple intrinsic frames of reference are formed and spatial relations are anchored to each individual frame of reference. Multiple such representations may co-exist and interactively determine a person's spatial performance.
1. Angular distribution of large qsub(T) muon pairs in different reference frames
International Nuclear Information System (INIS)
Lindfors, J.
1979-01-01
The angular distribution of large transverse momentum muon pairs produced in hadron-hadron collisions is calculated in lowest order of perturbative QCD. It is shown that for the process quark-antiquark → gluon + μ + μ - the polar and azimuthal angle distributions can be made independent of the parton distributions by choosing a special reference frame, the Collins-Soper frame, but for the process quark + gluon → quark + μ + μ - this is not possible. (author)
2. Quantum reference frames and their applications to thermodynamics.
Science.gov (United States)
Popescu, Sandu; Sainz, Ana Belén; Short, Anthony J; Winter, Andreas
2018-07-13
We construct a quantum reference frame, which can be used to approximately implement arbitrary unitary transformations on a system in the presence of any number of extensive conserved quantities, by absorbing any back action provided by the conservation laws. Thus, the reference frame at the same time acts as a battery for the conserved quantities. Our construction features a physically intuitive, clear and implementation-friendly realization. Indeed, the reference system is composed of the same types of subsystems as the original system and is finite for any desired accuracy. In addition, the interaction with the reference frame can be broken down into two-body terms coupling the system to one of the reference frame subsystems at a time. We apply this construction to quantum thermodynamic set-ups with multiple, possibly non-commuting conserved quantities, which allows for the definition of explicit batteries in such cases.This article is part of a discussion meeting issue 'Foundations of quantum mechanics and their impact on contemporary society'. © 2018 The Author(s).
3. The resource theory of quantum reference frames: manipulations and monotones
International Nuclear Information System (INIS)
2008-01-01
Every restriction on quantum operations defines a resource theory, determining how quantum states that cannot be prepared under the restriction may be manipulated and used to circumvent the restriction. A superselection rule (SSR) is a restriction that arises through the lack of a classical reference frame and the states that circumvent it (the resource) are quantum reference frames. We consider the resource theories that arise from three types of SSRs, associated respectively with lacking: (i) a phase reference, (ii) a frame for chirality, and (iii) a frame for spatial orientation. Focusing on pure unipartite quantum states (and in some cases restricting our attention even further to subsets of these), we explore single-copy and asymptotic manipulations. In particular, we identify the necessary and sufficient conditions for a deterministic transformation between two resource states to be possible and, when these conditions are not met, the maximum probability with which the transformation can be achieved. We also determine when a particular transformation can be achieved reversibly in the limit of arbitrarily many copies and find the maximum rate of conversion. A comparison of the three resource theories demonstrates that the extent to which resources can be interconverted decreases as the strength of the restriction increases. Along the way, we introduce several measures of frameness and prove that these are monotonically non-increasing under various classes of operations that are permitted by the SSR
4. Cross-Sensory Transfer of Reference Frames in Spatial Memory
Science.gov (United States)
Kelly, Jonathan W.; Avraamides, Marios N.
2011-01-01
Two experiments investigated whether visual cues influence spatial reference frame selection for locations learned through touch. Participants experienced visual cues emphasizing specific environmental axes and later learned objects through touch. Visual cues were manipulated and haptic learning conditions were held constant. Imagined perspective…
5. Developing a Frame of Reference for understanding configuration systems
DEFF Research Database (Denmark)
2008-01-01
This paper uses the theory of technical systems to develop a frame of reference of product configuration systems. Following a definition of the configuration task, product model and product configuration system the theory of technical systems are presented. Configuration systems are then related...
6. The International Celestial Reference Frame (ICRF) and the Relationship Between Frames
Science.gov (United States)
Ma, Chopo
2000-01-01
The International Celestial Reference Frame (ICRF), a catalog of VLBI source positions, is now the basis for astrometry and geodesy. Its construction and extension/maintenance will be discussed as well as the relationship of the ICRF, ITRF, and EOP/nutation.
7. DQ reference frame modeling and control of single-phase active power decoupling circuits
DEFF Research Database (Denmark)
Tang, Yi; Qin, Zian; Blaabjerg, Frede
2015-01-01
. This paper presents the dq synchronous reference frame modeling of single-phase power decoupling circuits and a complete model describing the dynamics of dc-link ripple voltage is presented. The proposed model is universal and valid for both inductive and capacitive decoupling circuits, and the input...... of decoupling circuits can be either dependent or independent of its front-end converters. Based on this model, a dq synchronous reference frame controller is designed which allows the decoupling circuit to operate in two different modes because of the circuit symmetry. Simulation and experimental results...... are presented to verify the effectiveness of the proposed modeling and control method....
8. Selection of spatial reference frames depends on task's demands
Directory of Open Access Journals (Sweden)
Greeshma Sharma
2016-12-01
Full Text Available Spatial reference frames (SRF are the means of representing spatial relations or locations either in an egocentric coordinate system (centred on navigator or in an allocentric coordinate system (Centred on object. It is necessary to understand when and how spatial representation switches between allocentric and egocentric reference frames in context to spatial tasks. The objective of this study was to explore if the elementary spatial representation does exist, whether it would remain consistent or change under the influence of a task's demand. Also, we explored how the SRF would assist if the environment is enriched with landmarks, having multiple routes for wayfinding. The results showed that the switching of SRF depends not only on the default representation but also on a task's demand. They also demonstrated that participants who were using allocentric representation performed better in the presence of landmarks.
9. Dissociating contributions of head and torso to spatial reference frames
DEFF Research Database (Denmark)
Alsmith, Adrian J T; Ferrè, Elisa R; Longo, Matthew R.
2017-01-01
contribution of each part to spatial judgments. Both the head and the torso contributed to judgements, though with greater contributions from the torso. A second experiment manipulating visual contrast of the torso showed that this does not reflect low-level differences in visual salience between body parts....... Our results demonstrate that spatial perspective-taking relies on a weighted combination of reference frames centred on different parts of the body....
10. Representing Spatial Layout According to Intrinsic Frames of Reference.
Science.gov (United States)
Xie, Chaoxiang; Li, Shiyi; Tao, Weidong; Wei, Yiping; Sun, Hong-Jin
2017-01-01
Mou and McNamara have suggested that object locations are represented according to intrinsic reference frames. In three experiments, we investigated the limitations of intrinsic reference frames as a mean to represent object locations in spatial memory. Participants learned the locations of seven or eight common objects in a rectangular room and then made judgments of relative direction based on their memory of the layout. The results of all experiments showed that when all objects were positioned regularly, judgments of relative direction were faster or more accurate for novel headings that were aligned with the primary intrinsic structure than for other novel headings; however, when one irregularly positioned object was added to the layout, this advantage was eliminated. The experiments further indicated that with a single view at study, participants could represent the layout from either an egocentric orientation or a different orientation, according to experimental instructions. Together, these results suggest that environmental reference frames and intrinsic axes can influence performance for novel headings, but their role in spatial memory depends on egocentric experience, layout regularity, and instructions.
11. Optical position meters analyzed in the noninertial reference frames
International Nuclear Information System (INIS)
Tarabrin, Sergey P.; Seleznyov, Alexander A.
2008-01-01
In the framework of general relativity we develop a method for the analysis of the operation of the optical position meters in their photodetectors proper reference frames. These frames are noninertial in general due to the action of external fluctuative forces on meters test masses, including detectors. For comparison we also perform the calculations in the laboratory (globally inertial) reference frame and demonstrate that for certain optical schemes laboratory-based analysis results in unmeasurable quantities, in contrast to the detector-based analysis. We also calculate the response of the simplest optical meters to weak plane gravitational waves and fluctuative motions of their test masses. It is demonstrated that for the round-trip meter analysis in both the transverse-traceless (TT) and local Lorentz (LL) gauges produces equal results, while for the forward-trip meter corresponding results differ in accordance with different physical assumptions (e.g. procedure of clocks synchronization) implicitly underlying the construction of the TT and LL gauges.
12. Rate of alignment and communication using quantum systems in the absence of a shared frame of reference
Science.gov (United States)
Skotiniotis, Michael
Quantum information theory is concerned with the storage, transmission, and manipulation of information that is represented in the degrees of freedom of quantum systems. These degrees of freedom are described relative to an external frame of reference. The lack of a requisite frame of reference imposes restrictions on the types of states quantum systems can be prepared in and the type of operations that can be performed on quantum systems. This thesis is concerned with the communication between two parties that lack a shared frame of reference. Specifically, I introduce a protocol whereby the parties can align their respective frames of reference, and a protocol for communicating quantum information in a reference frame independent manner. Using the accessible information to quantify the success of a reference frame alignment protocol I propose a new measure—the alignment rate—for quantifying the ability of a quantum state to stand in place of a classical frame of reference. I show that for the case where Alice and Bob lack a shared frame of reference associated with the groups G = U(1) and G = ZM (the finite cyclic group of M elements), the alignment rate is equal to the regularized, linearized G-asymmetry. The latter is a unique measure of the frameness of a quantum state and my result provides an operational interpretation of the G-asymmetry that was thus far lacking. In addition, I show that the alignment rate for finite cyclic groups of more than three elements is super-additive under the tensor product of two distinct pure quantum states. The latter is, to my knowledge, the first instance of a regularized quantity that exhibits super-additivity. In addition, I propose a reference-frame-independent protocol for communicating quantum information in the absence of a shared frame of reference associated with a general finite group G. The protocol transmits m logical qudits using r + m physical qudits prepared in a specific state that is reference-frame
13. Search for evidence of a preferred reference frame
International Nuclear Information System (INIS)
Warburton, R.J.; Goodkind, J.M.
1976-01-01
Some gravity theories, in contradiction to general relativity, allow the existence of a universal preferred reference frame. Also allowed in some theories can be a galaxy-induced anisotropy of the gravitation constant. The parametrized post-Newtonian theory predicts that in these cases there will be anomalous Earth tide amplitudes at specific frequencies. An 18-month Earth tide record obtained with the superconducting gravimeter has been examined for such anomalies. The data allow for the existence of such effects but cannot prove it because of uncertainties concerning geophysical perturbations of the tides. However, an upper limit to the preferred frame parameter, α 2 , of the parametrized post-Newtonian formalism is established at 2 x 10 -3 . The results also set a less rigorous limit on the anisotropy parameter, zeta/sub omega/, of order 10 -3
14. A Modernized National Spatial Reference System in 2022: Focus on the Caribbean Terrestrial Reference Frame
Science.gov (United States)
Roman, D. R.
2017-12-01
In 2022, the National Geodetic Survey will replace all three NAD 83 reference frames the four new terrestrial reference frames. Each frame will be named after a tectonic plate (North American, Pacific, Caribbean and Mariana) and each will be related to the IGS frame through three Euler Pole parameters (EPPs). This talk will focus on practical application in the Caribbean region. A working group is being re-established for development of the North American region and will likely also result in analysis of the Pacific region as well. Both of these regions are adequately covered with existing CORS sites to model the EPPs. The Mariana region currently lacks sufficient coverage, but a separate project is underway to collect additional information to help in defining EPPs for that region at a later date. The Caribbean region has existing robust coverage through UNAVCO's COCONet and other data sets, but these require further analysis. This discussion will focus on practical examination of Caribbean sites to establish candidates for determining the Caribbean frame EPPs as well as an examination of any remaining velocities that might inform a model of the remaining velocities within that frame (Intra-Frame Velocity Model). NGS has a vested interest in defining such a model to meet obligations to U.S. citizens in Puerto Rico and the U.S. Virgin Islands. Beyond this, NGS aims to collaborate with other countries in the region through efforts with SIRGAS and UN-GGIM-Americas for a more acceptable regional model to serve everyone's needs.
15. On the Assessment of Global Terrestrial Reference Frame Temporal Variations
Science.gov (United States)
Ampatzidis, Dimitrios; Koenig, Rolf; Zhu, Shengyuan
2015-04-01
Global Terrestrial Reference Frames (GTRFs) as the International Terrestrial Reference Frame (ITRF) provide reliable 4-D position information (3-D coordinates and their evolution through time). The given 3-D velocities play a significant role in precise position acquisition and are estimated from long term coordinate time series from the space-geodetic techniques DORIS, GNSS, SLR, and VLBI. GTRFs temporal evolution is directly connected with their internal stability: The more intense and inhomogeneous velocity field, the less stable TRF is derived. The assessment of the quality of the GTRF is mainly realized by comparing it to each individual technique's reference frame. E.g the comparison of GTRFs to SLR-only based TRF gives the sense of the ITRF stability with respect to the Geocenter and scale and their associated rates respectively. In addition, the comparison of ITRF to the VLBI-only based TRF can be used for the scale validation. However, till now there is not any specified methodology for the total assessment (in terms of origin, orientation and scale respectively) of the temporal evolution and GTRFs associated accuracy. We present a new alternative diagnostic tool for the assessment of GTRFs temporal evolution based on the well-known time-dependent Helmert type transformation formula (three shifts, three rotations and scale rates respectively). The advantage of the new methodology relies on the fact that it uses the full velocity field of the TRF and therefore all points not just the ones common to different techniques. It also examines simultaneously rates of origin, orientation and scale. The methodology is presented and implemented to the two existing GTRFs on the market (ITRF and DTRF which is computed from DGFI) , the results are discussed. The results also allow to compare directly each GTRF dynamic behavior. Furthermore, the correlations of the estimated parameters can also provide useful information to the proposed GTRFs assessment scheme.
16. Frames of Reference and Some of its Applications
OpenAIRE
Bel, Ll.
1998-01-01
We define a Frame of reference as a two ingredients concept: A meta-rigid motion, which is a generalization of a Born motion, and a chorodesic synchronization, which is an adapted foliation. At the end of the line we uncover a low-level 3-dimensional geometry with constant curvature and a corresponding coordinated proper-time scale. We discuss all these aspects both from the geometrical point of view as from the point of view of some of the physical applications derived from them.
17. A New Synchronous Reference Frame-Based Method for Single-Phase Shunt Active Power Filters
DEFF Research Database (Denmark)
Monfared, Mohammad; Golestan, Saeed; Guerrero, Josep M.
2013-01-01
This paper deals with the design of a novel method in the synchronous reference frame (SRF) to extract the reference compensating current for single-phase shunt active power filters (APFs). Unlike previous works in the SRF, the proposed method has an innovative feature that it does not need...... the fictitious current signal. Frequency-independent operation, accurate reference current extraction and relatively fast transient response are other key features of the presented strategy. The effectiveness of the proposed method is investigated by means of detailed mathematical analysis. The results confirm...
18. Estimating the Celestial Reference Frame via Intra-Technique Combination
Science.gov (United States)
Iddink, Andreas; Artz, Thomas; Halsig, Sebastian; Nothnagel, Axel
2016-12-01
One of the primary goals of Very Long Baseline Interferometry (VLBI) is the determination of the International Celestial Reference Frame (ICRF). Currently the third realization of the internationally adopted CRF, the ICRF3, is under preparation. In this process, various optimizations are planned to realize a CRF that does not benefit only from the increased number of observations since the ICRF2 was published. The new ICRF can also benefit from an intra-technique combination as is done for the Terrestrial Reference Frame (TRF). Here, we aim at estimating an optimized CRF by means of an intra-technique combination. The solutions are based on the input to the official combined product of the International VLBI Service for Geodesy and Astrometry (IVS), also providing the radio source parameters. We discuss the differences in the setup using a different number of contributions and investigate the impact on TRF and CRF as well as on the Earth Orientation Parameters (EOPs). Here, we investigate the differences between the combined CRF and the individual CRFs from the different analysis centers.
19. Impact of quasar proper motions on the alignment between the International Celestial Reference Frame and the Gaia reference frame
Science.gov (United States)
Liu, J.-C.; Malkin, Z.; Zhu, Z.
2018-03-01
The International Celestial Reference Frame (ICRF) is currently realized by the very long baseline interferometry (VLBI) observations of extragalactic sources with the zero proper motion assumption, while Gaia will observe proper motions of these distant and faint objects to an accuracy of tens of microarcseconds per year. This paper investigates the difference between VLBI and Gaia quasar proper motions and it aims to understand the impact of quasar proper motions on the alignment of the ICRF and Gaia reference frame. We use the latest time series data of source coordinates from the International VLBI Service analysis centres operated at Goddard Space Flight Center (GSF2017) and Paris observatory (OPA2017), as well as the Gaia auxiliary quasar solution containing 2191 high-probability optical counterparts of the ICRF2 sources. The linear proper motions in right ascension and declination of VLBI sources are derived by least-squares fits while the proper motions for Gaia sources are simulated taking into account the acceleration of the Solar system barycentre and realistic uncertainties depending on the source brightness. The individual and global features of source proper motions in GSF2017 and OPA2017 VLBI data are found to be inconsistent, which may result from differences in VLBI observations, data reduction and analysis. A comparison of the VLBI and Gaia proper motions shows that the accuracies of the components of rotation and glide between the two systems are 2-4 μas yr- 1 based on about 600 common sources. For the future alignment of the ICRF and Gaia reference frames at different wavelengths, the proper motions of quasars must necessarily be considered.
20. Ipsilateral wrist-ankle movements in the sagittal plane encoded in extrinsic reference frame.
Science.gov (United States)
Muraoka, Tetsuro; Ishida, Yuki; Obu, Takashi; Crawshaw, Larry; Kanosue, Kazuyuki
2013-04-01
When performing oscillatory movements of two joints in the sagittal plane, there is a directional constraint for performing such movements. Previous studies could not distinguish whether the directional constraint reflected movement direction encoded in the extrinsic (outside the body) reference frame or in the intrinsic (the participants' torso/head) reference frame since participants performed coordinated movements in a sitting position where the torso/head was stationary relative to the external world. In order to discern the reference frame in the present study, participants performed paced oscillatory movements of the ipsilateral wrist and ankle in the sagittal plane in a standing position so that the torso/head moved relative to the external world. The coordinated movements were performed in one of two modes of coordination, moving the hand upward concomitant with either ankle plantarflexion or ankle dorsiflexion. The same directional mode relative to extrinsic space was more stable and accurate as compared with the opposite directional mode. When forearm position was changed from the pronated position to the supinated position, similar results were obtained, indicating that the results were independent of a particular coupling of muscles. These findings suggest that the directional constraint on ipsilateral joints movements in the sagittal plane reflects movement direction encoded in the extrinsic reference frame. Copyright © 2013 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.
1. Defining an absolute reference frame for 'clumped' isotope studies of CO 2
Science.gov (United States)
Dennis, Kate J.; Affek, Hagit P.; Passey, Benjamin H.; Schrag, Daniel P.; Eiler, John M.
2011-11-01
instruments, independent of laboratory-specific analytical or methodological differences. We then discuss the use of intra-laboratory secondary reference frames (e.g., based on carbonate standards) that can be more easily used to track the evolution of each laboratory's empirical transfer function. Finally, we show inter-laboratory reproducibility on the order of ±0.010 (1 σ) for four carbonate standards, and present revised paleotemperature scales that should be used to convert carbonate clumped isotope signatures to temperature when using the absolute reference frame described here. Even when using the reference frame, small discrepancies remain between two previously published synthetic carbonate calibrations. We discuss possible reasons for these discrepancies, and highlight the need for additional low temperature (<15 °C) synthetic carbonate experiments.
2. Reframing Student Affairs Leadership: An Analysis of Organizational Frames of Reference and Locus of Control
Science.gov (United States)
Tull, Ashley; Freeman, Jerrid P.
2011-01-01
Examined in this study were the identified frames of reference and locus of control used by 478 student affairs administrators. Administrator responses were examined to identify frames of reference most commonly used and their preference order. Locus of control most commonly used and the relationship between frames of reference and locus of…
3. Quantum cosmology with effects of a preferred reference frame
International Nuclear Information System (INIS)
2010-01-01
Recently, we presented a gravity model by generalizing the Brans-Dicke theory which is suitable for studying the metric signature transition dynamics without using an imaginary time parameter. Adding a suitable scalar potential described in terms of the Brans-Dicke scalar field 'Φ-tilde, this alternative theory is used to study the Wheeler-DeWitt approach of quantum cosmology. We assumed that the universe is defined in a flat Robertson-Walker metric with Lorentzian signature. In that case, the Wheeler-DeWitt wavefunctional is obtained as two-dimensional quantum harmonic oscillator convergent polynomials for both of the choices of positive and negative values of the Brans-Dicke parameter. Here we choose a preferred reference frame with a time coordinate of 'γ' which relates to time of cosmological free falling observer 't' as 'dt= Φ-tilde(γ)dγ'.
4. The frames of reference of the motor-visual aftereffect.
Directory of Open Access Journals (Sweden)
Guido Barchiesi
Full Text Available Repeatedly performing similar motor acts produces short-term adaptive changes in the agent's motor system. One striking use-dependent effect is the motor-to-visual aftereffect (MVA, a short-lasting negative bias in the conceptual categorization of visually-presented training-related motor behavior. The MVA is considered the behavioral counterpart of the adaptation of visuomotor neurons that code for congruent executed and observed motor acts. Here we characterize which features of the motor training generate the MVA, along 3 main dimensions: a the relative role of motor acts vs. the semantics of the task-set; b the role of muscular-specific vs. goal-specific training and c the spatial frame of reference with respect to the whole body. Participants were asked to repeatedly push or pull some small objects in a bowl as we varied different components of adapting actions across three experiments. The results show that a the semantic value of the instructions given to the participant have no role in generating the MVA, which depends only on the motor meaning of the training act; b both intrinsic body movements and extrinsic action goals contribute simultaneously to the genesis of the MVA and c changes in the relative position of the acting hand compared to the observed hand, when they do not involve changes to the movement performed or to the action meaning, do not have an effect on the MVA. In these series of experiments we confirm that recent motor experiences produce measurable changes in how humans see each others' actions. The MVA is an exquisite motor effect generated by two distinct motor sub-systems, one operating in an intrinsic, muscular specific, frame of reference and the other operating in an extrinsic motor space.
5. A Global Moving Hotspot Reference Frame: How well it fits?
Science.gov (United States)
Doubrovine, P. V.; Steinberger, B.; Torsvik, T. H.
2010-12-01
Since the early 1970s, when Jason Morgan proposed that hotspot tracks record motion of lithosphere over deep-seated mantle plumes, the concept of fixed hotspots has dominated the way we think about absolute plate reconstructions. In the last decade, with compelling evidence for southward drift of the Hawaiian hotspot from paleomagnetic studies, and for the relative motion between the Pacific and Indo-Atlantic hotspots from refined plate circuit reconstructions, the perception changed and a global moving hotspot reference frame (GMHRF) was introduced, in which numerical models of mantle convection and advection of plume conduits in the mantle flow were used to estimate hotspot motion. This reference frame showed qualitatively better performance in fitting hotspot tracks globally, but the error analysis and formal estimates of the goodness of fitted rotations were lacking in this model. Here we present a new generation of the GMHRF, in which updated plate circuit reconstructions and radiometric age data from the hotspot tracks were combined with numerical models of plume motion, and uncertainties of absolute plate rotations were estimated through spherical regression analysis. The overall quality of fit was evaluated using a formal statistical test, by comparing misfits produced by the model with uncertainties assigned to the data. Alternative plate circuit models linking the Pacific plate to the plates of Indo-Atlantic hemisphere were tested and compared to the fixed hotspot models with identical error budgets. Our results show that, with an appropriate choice of the Pacific plate circuit, it is possible to reconcile relative plate motions and modeled motions of mantle plumes globally back to Late Cretaceous time (80 Ma). In contrast, all fixed hotspot models failed to produce acceptable fits for Paleogene to Late Cretaceous time (30-80 Ma), highlighting significance of relative motion between the Pacific and Indo-Atlantic hotspots during this interval. The
6. Consistent realization of Celestial and Terrestrial Reference Frames
Science.gov (United States)
Kwak, Younghee; Bloßfeld, Mathis; Schmid, Ralf; Angermann, Detlef; Gerstl, Michael; Seitz, Manuela
2018-03-01
The Celestial Reference System (CRS) is currently realized only by Very Long Baseline Interferometry (VLBI) because it is the space geodetic technique that enables observations in that frame. In contrast, the Terrestrial Reference System (TRS) is realized by means of the combination of four space geodetic techniques: Global Navigation Satellite System (GNSS), VLBI, Satellite Laser Ranging (SLR), and Doppler Orbitography and Radiopositioning Integrated by Satellite. The Earth orientation parameters (EOP) are the link between the two types of systems, CRS and TRS. The EOP series of the International Earth Rotation and Reference Systems Service were combined of specifically selected series from various analysis centers. Other EOP series were generated by a simultaneous estimation together with the TRF while the CRF was fixed. Those computation approaches entail inherent inconsistencies between TRF, EOP, and CRF, also because the input data sets are different. A combined normal equation (NEQ) system, which consists of all the parameters, i.e., TRF, EOP, and CRF, would overcome such an inconsistency. In this paper, we simultaneously estimate TRF, EOP, and CRF from an inter-technique combined NEQ using the latest GNSS, VLBI, and SLR data (2005-2015). The results show that the selection of local ties is most critical to the TRF. The combination of pole coordinates is beneficial for the CRF, whereas the combination of Δ UT1 results in clear rotations of the estimated CRF. However, the standard deviations of the EOP and the CRF improve by the inter-technique combination which indicates the benefits of a common estimation of all parameters. It became evident that the common determination of TRF, EOP, and CRF systematically influences future ICRF computations at the level of several μas. Moreover, the CRF is influenced by up to 50 μas if the station coordinates and EOP are dominated by the satellite techniques.
7. Electrodynamics in Arbitrary Reference Frames and in Arbitrary Material Media
International Nuclear Information System (INIS)
Horzela, A.; Kapuscik, E.; Widomski, M.
1999-01-01
Full text: The investigation of electromagnetic phenomena in material media still belongs to the most difficult tasks of electrodynamics. Complexity and variability of material media practically exclude effective applications of methods and computational techniques elaborated in the framework of standard microscopic electrodynamics with classical vacuum as a ground state. In order to obtain satisfactorily exact descriptions of electromagnetic properties of complex material media one is enforced to use methods and approximations which are difficult to control. Moreover, they usually break covariance properties and the results obtained are valid in one reference frame which choice remains subjective and model dependent. Some time ago we have proposed a reformulation of Maxwell electrodynamics which opens new ways in study of electromagnetic processes in material media. The formalism gets rid of assumptions characteristic for vacuum electrodynamics only and it avoids the usage of constitutive relations as primary relations put on quantities needed for a complete description of an electromagnetic system. Fundamental properties of all electromagnetic quantities are their uniquely defined transformation rules and their analysis allows to determine the possible relations between them. Within such a scheme it is possible to introduce constitutive relations which do not have analogies in macroscopic classical electrodynamics. They may be used in description of microscopic electromagnetic processes in a different way than it is done in the framework of quantum electrodynamics. (author)
8. The reference frame for encoding and retention of motion depends on stimulus set size.
Science.gov (United States)
Huynh, Duong; Tripathy, Srimant P; Bedell, Harold E; Öğmen, Haluk
2017-04-01
The goal of this study was to investigate the reference frames used in perceptual encoding and storage of visual motion information. In our experiments, observers viewed multiple moving objects and reported the direction of motion of a randomly selected item. Using a vector-decomposition technique, we computed performance during smooth pursuit with respect to a spatiotopic (nonretinotopic) and to a retinotopic component and compared them with performance during fixation, which served as the baseline. For the stimulus encoding stage, which precedes memory, we found that the reference frame depends on the stimulus set size. For a single moving target, the spatiotopic reference frame had the most significant contribution with some additional contribution from the retinotopic reference frame. When the number of items increased (Set Sizes 3 to 7), the spatiotopic reference frame was able to account for the performance. Finally, when the number of items became larger than 7, the distinction between reference frames vanished. We interpret this finding as a switch to a more abstract nonmetric encoding of motion direction. We found that the retinotopic reference frame was not used in memory. Taken together with other studies, our results suggest that, whereas a retinotopic reference frame may be employed for controlling eye movements, perception and memory use primarily nonretinotopic reference frames. Furthermore, the use of nonretinotopic reference frames appears to be capacity limited. In the case of complex stimuli, the visual system may use perceptual grouping in order to simplify the complexity of stimuli or resort to a nonmetric abstract coding of motion information.
9. A reference frame for blood volume in children and adolescents
Directory of Open Access Journals (Sweden)
Donckerwolcke Raymond
2006-02-01
Full Text Available Abstract Background Our primary purpose was to determine the normal range and variability of blood volume (BV in healthy children, in order to provide reference values during childhood and adolescence. Our secondary aim was to correlate these vascular volumes to body size parameters and pubertal stages, in order to determine the best normalisation parameter. Methods Plasma volume (PV and red cell volume (RCV were measured and F-cell ratio was calculated in 77 children with idiopathic nephrotic syndrome in drug-free remission (mean age, 9.8 ± 4.6 y. BV was calculated as the sum of PV and RCV. Due to the dependence of these values on age, size and sex, all data were normalised for body size parameters. Results BV normalised for lean body mass (LBM did not differ significantly by sex (p Conclusion LBM was the anthropometric index most closely correlated to vascular fluid volumes, independent of age, gender and pubertal stage.
10. Examining egocentric and allocentric frames of reference in virtual space systems
NARCIS (Netherlands)
Friedman, A.
2005-01-01
The aim of this paper is to examine the egocentric and allocentric frames of reference, through evidence from both gesture and linguistic communication. The action of frames of reference, helps the user refer to the agent as a base for movement or to the object as a guiding point. We will show that
11. Geometric Cues, Reference Frames, and the Equivalence of Experienced-Aligned and Novel-Aligned Views in Human Spatial Memory
Science.gov (United States)
Kelly, Jonathan W.; Sjolund, Lori A.; Sturz, Bradley R.
2013-01-01
Spatial memories are often organized around reference frames, and environmental shape provides a salient cue to reference frame selection. To date, however, the environmental cues responsible for influencing reference frame selection remain relatively unknown. To connect research on reference frame selection with that on orientation via…
12. Different reference frames can lead to different hand transplantation decisions by patients and physicians.
Science.gov (United States)
Edgell, S E; McCabe, S J; Breidenbach, W C; Neace, W P; LaJoie, A S; Abell, T D
2001-03-01
Different frames of reference can affect one's assessment of the value of hand transplantation. This can result in different yet rational decisions by different groups of individuals, especially patients and physicians. In addition, factors other than frames of reference can affect one's evaluation of hand transplantation, which can result in different decisions.
13. Tracking down abstract linguistic meaning: neural correlates of spatial frame of reference ambiguities in language.
Directory of Open Access Journals (Sweden)
Gabriele Janzen
Full Text Available This functional magnetic resonance imaging (fMRI study investigates a crucial parameter in spatial description, namely variants in the frame of reference chosen. Two frames of reference are available in European languages for the description of small-scale assemblages, namely the intrinsic (or object-oriented frame and the relative (or egocentric frame. We showed participants a sentence such as "the ball is in front of the man", ambiguous between the two frames, and then a picture of a scene with a ball and a man--participants had to respond by indicating whether the picture did or did not match the sentence. There were two blocks, in which we induced each frame of reference by feedback. Thus for the crucial test items, participants saw exactly the same sentence and the same picture but now from one perspective, now the other. Using this method, we were able to precisely pinpoint the pattern of neural activation associated with each linguistic interpretation of the ambiguity, while holding the perceptual stimuli constant. Increased brain activity in bilateral parahippocampal gyrus was associated with the intrinsic frame of reference whereas increased activity in the right superior frontal gyrus and in the parietal lobe was observed for the relative frame of reference. The study is among the few to show a distinctive pattern of neural activation for an abstract yet specific semantic parameter in language. It shows with special clarity the nature of the neural substrate supporting each frame of spatial reference.
14. W production at LHC: lepton angular distributions and reference frames for probing hard QCD
International Nuclear Information System (INIS)
Richter-Was, E.; Was, Z.
2017-01-01
Precision tests of the Standard Model in the Strong and Electroweak sectors play a crucial role, among the physics program of LHC experiments. Because of the nature of proton-proton processes, observables based on the measurement of the direction and energy of final state leptons provide the most precise probes of such processes. In the present paper, we concentrate on the angular distribution of leptons from W → lν decays in the lepton-pair rest-frame. The vector nature of the intermediate state imposes that distributions are to a good precision described by spherical harmonics of at most second order. We argue, that contrary to general belief often expressed in the literature, the full set of angular coefficients can be measured experimentally, despite the presence of escaping detection neutrino in the final state. There is thus no principle difference with respect to the phenomenology of the Z/γ → l"+l"- Drell-Yan process. We show also, that with the proper choice of the reference frames, only one coefficient in this polynomial decomposition remains sizable, even in the presence of one or more high p_T jets. The necessary stochastic choice of the frames relies on probabilities independent from any coupling constants. In this way, electroweak effects (dominated by the V - A nature of W couplings to fermions), can be better separated from the ones of strong interactions. The separation is convenient for the measurements interpretation. (orig.)
15. Calibration of Robot Reference Frames for Enhanced Robot Positioning Accuracy
OpenAIRE
Cheng, Frank Shaopeng
2008-01-01
This chapter discussed the importance and methods of conducting robot workcell calibration for enhancing the accuracy of the robot TCP positions in industrial robot applications. It shows that the robot frame transformations define the robot geometric parameters such as joint position variables, link dimensions, and joint offsets in an industrial robot system. The D-H representation allows the robot designer to model the robot motion geometry with the four standard D-H parameters. The robot k...
16. Fronto-Parietal Brain Responses to Visuotactile Congruence in an Anatomical Reference Frame
Directory of Open Access Journals (Sweden)
Jakub Limanowski
2018-03-01
Full Text Available Spatially and temporally congruent visuotactile stimulation of a fake hand together with one’s real hand may result in an illusory self-attribution of the fake hand. Although this illusion relies on a representation of the two touched body parts in external space, there is tentative evidence that, for the illusion to occur, the seen and felt touches also need to be congruent in an anatomical reference frame. We used functional magnetic resonance imaging and a somatotopical, virtual reality-based setup to isolate the neuronal basis of such a comparison. Participants’ index or little finger was synchronously touched with the index or little finger of a virtual hand, under congruent or incongruent orientations of the real and virtual hands. The left ventral premotor cortex responded significantly more strongly to visuotactile co-stimulation of the same versus different fingers of the virtual and real hand. Conversely, the left anterior intraparietal sulcus responded significantly more strongly to co-stimulation of different versus same fingers. Both responses were independent of hand orientation congruence and of spatial congruence of the visuotactile stimuli. Our results suggest that fronto-parietal areas previously associated with multisensory processing within peripersonal space and with tactile remapping evaluate the congruence of visuotactile stimulation on the body according to an anatomical reference frame.
17. Fronto-Parietal Brain Responses to Visuotactile Congruence in an Anatomical Reference Frame.
Science.gov (United States)
Limanowski, Jakub; Blankenburg, Felix
2018-01-01
Spatially and temporally congruent visuotactile stimulation of a fake hand together with one's real hand may result in an illusory self-attribution of the fake hand. Although this illusion relies on a representation of the two touched body parts in external space, there is tentative evidence that, for the illusion to occur, the seen and felt touches also need to be congruent in an anatomical reference frame. We used functional magnetic resonance imaging and a somatotopical, virtual reality-based setup to isolate the neuronal basis of such a comparison. Participants' index or little finger was synchronously touched with the index or little finger of a virtual hand, under congruent or incongruent orientations of the real and virtual hands. The left ventral premotor cortex responded significantly more strongly to visuotactile co-stimulation of the same versus different fingers of the virtual and real hand. Conversely, the left anterior intraparietal sulcus responded significantly more strongly to co-stimulation of different versus same fingers. Both responses were independent of hand orientation congruence and of spatial congruence of the visuotactile stimuli. Our results suggest that fronto-parietal areas previously associated with multisensory processing within peripersonal space and with tactile remapping evaluate the congruence of visuotactile stimulation on the body according to an anatomical reference frame.
18. Some aspects of transformation of the nonlinear plasma equations to the space-independent frame
International Nuclear Information System (INIS)
Paul, S.N.; Chakraborty, B.
1982-01-01
Relativistically correct transformation of nonlinear plasma equations are derived in a space-independent frame. This transformation is useful in many ways because in place of partial differential equations one obtains a set of ordinary differential equations in a single independent variable. Equations of Akhiezer and Polovin (1956) for nonlinear plasma oscillations have been generalized and the results of Arons and Max (1974), and others for wave number shift and precessional rotation of electromagnetic wave are recovered in a space-independent frame. (author)
19. Frame independence of the inhomogeneous mixmaster chaos via Misner-Chitre-like variables
International Nuclear Information System (INIS)
Benini, Riccardo; Montani, Giovanni
2004-01-01
We outline the covariant nature, with respect to the choice of a reference frame, of the chaos characterizing the generic cosmological solution near the initial singularity, i.e., the so-called inhomogeneous mixmaster model. Our analysis is based on a gauge independent Arnowitt-Deser-Misner reduction of the dynamics to the physical degrees of freedom. The resulting picture shows how the inhomogeneous mixmaster model is isomorphic point by point in space to a billiard on a Lobachevsky plane. Indeed, the existence of an asymptotic (energylike) constant of the motion allows one to construct the Jacobi metric associated with the geodesic flow and to calculate a nonzero Lyapunov exponent in each space point. The chaos covariance emerges from the independence of our scheme with respect to the form of the lapse function and the shift vector; the origin of this result relies on the dynamical decoupling of the space points which takes place near the singularity, due to the asymptotic approach of the potential term to infinite walls. At the ground of the obtained dynamical scheme is the choice of Misner-Chitre-like variables which allows one to fix the billiard potential walls
20. Shift of the spectrum in the non-inertial reference frame
International Nuclear Information System (INIS)
Kudykina, T. A.; Pervak, A. I.
2012-01-01
We propose a new natural explanation of the spectral redshift (blue shift) arguing that the rotatory non-inertial reference frame of cosmological objects is the main reason of the shift of the frequency of emitting light. (Author)
1. Estimation of Frame Independent and Enhancement Components for Speech Communication over Packet Networks
DEFF Research Database (Denmark)
Giacobello, Daniele; Murthi, Manohar N.; Christensen, Mads Græsbøll
2010-01-01
In this paper, we describe a new approach to cope with packet loss in speech coders. The idea is to split the information present in each speech packet into two components, one to independently decode the given speech frame and one to enhance it by exploiting interframe dependencies. The scheme...... is based on sparse linear prediction and a redefinition of the analysis-by-synthesis process. We present Mean Opinion Scores for the presented coder with different degrees of packet loss and show that it performs similarly to frame dependent coders for low packet loss probability and similarly to frame...
2. How role distribution influences choice of spatial reference frames in a virtual collaborative task
OpenAIRE
Pouliquen-Lardy , Lauriane; Milleville-Pennel , Isabelle; Guillaume , François; Mars , Franck
2014-01-01
International audience; We investigated the effects of role distribution on individuals' choice of reference frames in a two-person task. Pairs of participants had to move a virtual block in a constraint immersive virtual environment: only one of them could manipulate the ob-ject, his coworker guided him in the VE. Results show that the guiding operators used more addressee-centered frames of ref-erence than the manipulators. They also suggest that the guides tried to facilitate the manipulat...
3. Updating of visual orientation in a gravity-based reference frame.
Science.gov (United States)
Niehof, Nynke; Tramper, Julian J; Doeller, Christian F; Medendorp, W Pieter
2017-10-01
The brain can use multiple reference frames to code line orientation, including head-, object-, and gravity-centered references. If these frames change orientation, their representations must be updated to keep register with actual line orientation. We tested this internal updating during head rotation in roll, exploiting the rod-and-frame effect: The illusory tilt of a vertical line surrounded by a tilted visual frame. If line orientation is stored relative to gravity, these distortions should also affect the updating process. Alternatively, if coding is head- or frame-centered, updating errors should be related to the changes in their orientation. Ten subjects were instructed to memorize the orientation of a briefly flashed line, surrounded by a tilted visual frame, then rotate their head, and subsequently judge the orientation of a second line relative to the memorized first while the frame was upright. Results showed that updating errors were mostly related to the amount of subjective distortion of gravity at both the initial and final head orientation, rather than to the amount of intervening head rotation. In some subjects, a smaller part of the updating error was also related to the change of visual frame orientation. We conclude that the brain relies primarily on a gravity-based reference to remember line orientation during head roll.
4. The effect of the reference frame on the thermophysical properties of an ideal gas
International Nuclear Information System (INIS)
Speziale, Cg.
1986-01-01
The effect that the frame of reference has on the thermophysical properties of an ideal gas is examined from a fundamental theoretical standpoint based on the Boltzmann equation. In continuum mechanics, the principle of material frame in deference forbids the thermophysical properties of a fluid or solid to depend in any way on the motion of the reference frame. It is demonstrated that the Boltzmann equation is only consistent with material frame-indeffrence in a strong approximate sense provided that the gas is not highly rarefield and, thus, well within the limits of classical continuum mechanics. Estimates of the mean free times for which material frame-indifference can be invoked in the modeling of gas flows are provided from an analysis of the problem of heat conduction in a rigidly rotating gas. Applications of these results in obtaining asymptotic solutions of the Boltzmann equation for the continuum description of an ideal gas are discussed briefly
5. Contextual cueing of tactile search is coded in an anatomical reference frame.
Science.gov (United States)
Assumpção, Leonardo; Shi, Zhuanghua; Zang, Xuelian; Müller, Hermann J; Geyer, Thomas
2018-04-01
This work investigates the reference frame(s) underlying tactile context memory, a form of statistical learning in a tactile (finger) search task. In this task, if a searched-for target object is repeatedly encountered within a stable spatial arrangement of task-irrelevant distractors, detecting the target becomes more efficient over time (relative to nonrepeated arrangements), as learned target-distractor spatial associations come to guide tactile search, thus cueing attention to the target location. Since tactile search displays can be represented in several reference frames, including multiple external and an anatomical frame, in Experiment 1 we asked whether repeated search displays are represented in tactile memory with reference to an environment-centered or anatomical reference frame. In Experiment 2, we went on examining a hand-centered versus anatomical reference frame of tactile context memory. Observers performed a tactile search task, divided into a learning and test session. At the transition between the two sessions, we introduced postural manipulations of the hands (crossed ↔ uncrossed in Expt. 1; palm-up ↔ palm-down in Expt. 2) to determine the reference frame of tactile contextual cueing. In both experiments, target-distractor associations acquired during learning transferred to the test session when the placement of the target and distractors was held constant in anatomical, but not external, coordinates. In the latter, RTs were even slower for repeated displays. We conclude that tactile contextual learning is coded in an anatomical reference frame. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
6. NChina16: A stable geodetic reference frame for geological hazard studies in North China
Science.gov (United States)
Wang, Guoquan; Bao, Yan; Gan, Weijun; Geng, Jianghui; Xiao, Gengru; Shen, Jack S.
2018-04-01
We have developed a stable North China Reference Frame 2016 (NChina16) using five years of continuous GPS observations (2011.8-2016.8) from 12 continuously operating reference stations (CORS) fixed to the North China Craton. Applications of NChina16 in landslide and subsidence studies are illustrated in this article. A method for realizing a regional geodetic reference frame is introduced. The primary result of this study is the seven parameters for transforming Cartesian ECEF (Earth-Centered, Earth-Fixed) coordinates X, Y, and Z from the International GNSS Service Reference Frame 2008 (IGS08) to NChina16. The seven parameters include the epoch that is used to align the regional reference frame to IGS08 and the time derivatives of three translations and three rotations. The GIPSY-OASIS (V6.4) software package was used to obtain the precise point positioning (PPP) daily solutions with respect to IGS08. The frame stability of NChina16 is approximately 0.5 mm/year in both horizontal and vertical directions. This study also developed a regional model for correcting seasonal motions superimposed into the vertical component of the GPS-derived displacement time series. Long-term GPS observations (1999-2016) from five CORS in North China were used to develop the seasonal model. According to this study, the PPP daily solutions with respect to NChina16 could achieve 2-3 mm horizontal accuracy and 4-5 mm vertical accuracy after being modified by the regional model. NChina16 will be critical to study geodynamic problems in North China, such as earthquakes, faulting, subsidence, and landslides. The regional reference frame will be periodically updated every few years to mitigate degradation of the frame with time and be synchronized with the update of IGS reference frame.
7. Frames of References – Art Museums as Unique Visual Media
Directory of Open Access Journals (Sweden)
Aneta Hristova
2015-10-01
Full Text Available The age old activity of collecting arts is not intrinsically dependent on the art museum as separate architectural type. How was the art museum as an independent structure conceptualized and why? What was the idea behind that concept? Was it created as a medium consciously and what kind of messages was it supposed to deliver? What kind of unique “textual” overlaps the various disciplines of archaeology, art history, politics, literature, science and architecture created in order to produce what we today recognize as art museum space? This study focuses on the crucial historical moments of the late 17th century when such questions were posed for the first time within the classical discourse of the French architectural theory which followed the consolidation of French absolutism and the foundation of the Royal academies of arts and sciences, until the mid 19th century when the answers to those questions were finally exemplified in built architecture. The study gives a comprehensive overview of the cultural context art museums as public institutions emerged from and became new spatial models for collective cultivation.
8. Assessment of the possible contribution of space ties on-board GNSS satellites to the terrestrial reference frame
Science.gov (United States)
Bruni, Sara; Rebischung, Paul; Zerbini, Susanna; Altamimi, Zuheir; Errico, Maddalena; Santi, Efisio
2018-04-01
The realization of the international terrestrial reference frame (ITRF) is currently based on the data provided by four space geodetic techniques. The accuracy of the different technique-dependent materializations of the frame physical parameters (origin and scale) varies according to the nature of the relevant observables and to the impact of technique-specific errors. A reliable computation of the ITRF requires combining the different inputs, so that the strengths of each technique can compensate for the weaknesses of the others. This combination, however, can only be performed providing some additional information which allows tying together the independent technique networks. At present, the links used for that purpose are topometric surveys (local/terrestrial ties) available at ITRF sites hosting instruments of different techniques. In principle, a possible alternative could be offered by spacecrafts accommodating the positioning payloads of multiple geodetic techniques realizing their co-location in orbit (space ties). In this paper, the GNSS-SLR space ties on-board GPS and GLONASS satellites are thoroughly examined in the framework of global reference frame computations. The investigation focuses on the quality of the realized physical frame parameters. According to the achieved results, the space ties on-board GNSS satellites cannot, at present, substitute terrestrial ties in the computation of the ITRF. The study is completed by a series of synthetic simulations investigating the impact that substantial improvements in the volume and quality of SLR observations to GNSS satellites would have on the precision of the GNSS frame parameters.
9. UTC(SU) and EOP(SU) - the only legal reference frames of Russian Federation
Science.gov (United States)
Koshelyaevsky, Nikolay B.; Blinov, Igor Yu; Pasynok, Sergey L.
2015-08-01
There are two legal time reference frames in Russian Federation. UTC(SU) deals with atomic time and play a role of reference for legal timing through the whole country. The other one, EOP(SU), deals with Earth's orientation parameters and provides the official EOP data for scientific, technical and metrological applications in Russia.The atomic time is based on two essential hardware components: primary Cs fountain standards and ensemble of continuously operating H-masers as a time unit/time scale keeper. Basing on H-maser intercomparison system data, regular H-maser frequency calibration against Cs standards and time algorithm autonomous TA(SU) time scale is maintained by the Main Metrological Center. Since 2013 time unit in TA(SU) is the second (SU) reproduced independently by VNIIFTRI Cs primary standards in accordance to it’s definition in the SI. UTC(SU) is relied on TA(SU) and steering to UTC basing on TWSTFT/GNSS time link data. As a result TA(SU) stability level relative to TT considerably exceeds 1×10-15 for sample time one month and more, RMS[UTC-UTC(SU)] ≤ 3 ns for the period of 2013-2015. UTC(SU) is broadcasted by different national means such as specialized radio and TV stations, NTP servers and GLONASS. Signals of Russian radio stations contains DUT1 and dUT1 values at 0.1s and 0.02s resolution respectively.The definitive EOP(SU) are calculated by the Main Metrological Center basing on composition of the eight independent individual EOP data streams delivered by four Russian analysis centers: VNIIFTRI, Institute of Applied Astronomy, Information-Analytical Center of Russian Space Agency and Analysis Center of Russian Space Agency. The accuracy of ultra-rapid EOP values for 2014 is estimated ≤ 0.0006" for polar motion, ≤ 70 microseconds for UT1-UTC and ≤ 0.0003" for celestial pole offsets respectively.The other VNIIFTRI EOP activities can be grouped in three basic directions:- arrangement and carrying out GNSS and SLR observations at five
10. Binocular perception of slant about oblique axes relative to a visual frame of reference
NARCIS (Netherlands)
Ee, R. van; Erkelens, Casper J.
1995-01-01
From the literature it is known that the processing of disparity for slant is different in the presence and in the absence of a visual frame of reference. We elaborate the experimental finding that vertical disparity is not processed for slant perception in the presence of a visual reference. This
11. Thinking inside the box: Spatial frames of reference for drawing in Williams syndrome and typical development.
Science.gov (United States)
Hudson, Kerry D; Farran, Emily K
2017-09-01
Successfully completing a drawing relies on the ability to accurately impose and manipulate spatial frames of reference for the object that is being drawn and for the drawing space. Typically developing (TD) children use cues such as the page boundary as a frame of reference to guide the orientation of drawn lines. Individuals with Williams syndrome (WS) typically produce incohesive drawings; this is proposed to reflect a local processing bias. Across two studies, we provide the first investigation of the effect of using a frame of reference when drawing simple lines and shapes in WS and TD groups (matched for non-verbal ability). Individuals with WS (N=17 Experiment 1; N=18 Experiment 2) and TD children matched by non-verbal ability drew single lines (Experiment One) and whole shapes (Experiment Two) within a neutral, incongruent or congruent frame. The angular deviation of the drawn line/shape, relative to the model line/shape, was measured. Both groups were sensitive to spatial frames of reference when drawing single lines and whole shapes, imposed by a frame around the drawing space. A local processing bias in WS cannot explain poor drawing performance in WS. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
12. Current control of PMSM based on maximum torque control reference frame
Science.gov (United States)
Ohnuma, Takumi
2017-07-01
This study presents a new method of current controls of PMSMs (Permanent Magnet Synchronous Motors) based on a maximum torque control reference frame, which is suitable for high-performance controls of the PMSMs. As the issues of environment and energy increase seriously, PMSMs, one of the AC motors, are becoming popular because of their high-efficiency and high-torque density in various applications, such as electric vehicles, trains, industrial machines, and home appliances. To use the PMSMs efficiently, a proper current control of the PMSMs is necessary. In general, a rotational coordinate system synchronizing with the rotor is used for the current control of PMSMs. In the rotating reference frame, the current control is easier because the currents on the rotating reference frame can be expressed as a direct current in the controller. On the other hand, the torque characteristics of PMSMs are non-linear and complex; the PMSMs are efficient and high-density though. Therefore, a complicated control system is required to involve the relation between the torque and the current, even though the rotating reference frame is adopted. The maximum torque control reference frame provides a simpler way to control efficiently the currents taking the torque characteristics of the PMSMs into consideration.
13. Magnetic resonance described in the excitation dependent rotating frame of reference.
Science.gov (United States)
Tahayori, Bahman; Johnston, Leigh A; Mareels, Iven M Y; Farrell, Peter M
2008-01-01
An excitation dependent rotating frame of reference to observe the magnetic resonance phenomenon is introduced in this paper that, to the best of our knowledge, has not been used previously in the nuclear magnetic resonance context. The mathematical framework for this new rotating frame of reference is presented based on time scaling the Bloch equation after transformation to the classical rotating frame of reference whose transverse plane is rotating at the Larmor frequency. To this end, the Bloch equation is rewritten in terms of a magnetisation vector observed from the excitation dependent rotating frame of reference. The resultant Bloch equation is referred to as the time scaled Bloch equation. In the excitation dependent rotating frame of reference whose coordinates are rotating at the instantaneous Rabi frequency the observed magnetisation vector is a much slower signal than the true magnetisation in the rotating frame of reference. As a result the ordinary differential equation solvers have the ability to solve the time scaled version of the Bloch equation with a larger step size resulting in a smaller number of samples for solving the equation to a desired level of accuracy. The simulation results for different types of excitation are presented in this paper. This method may be used in true Bloch simulators in order to reduce the simulation time or increase the accuracy of the numerical solution. Moreover, the time scaled Bloch equation may be employed to determine the optimal excitation pattern in magnetic resonance imaging as well as designing pulses with better slice selectivity which is an active area of research in this field.
14. Exploring students' understanding of reference frames and time in Galilean and special relativity
International Nuclear Information System (INIS)
De Hosson, C; Kermen, I; Parizot, E
2010-01-01
This paper aims at exploring prospective physics teachers' reasoning associated with the concepts of reference frame, time and event which form the framework of the classical kinematics and that of the relativistic kinematics. About 100 prospective physics teachers were surveyed by means of a questionnaire involving classical kinematics situations and relativistic ones. The analysis of the answers shows a deep lack of understanding of both concepts of reference frame and event. Some students think that events may be simultaneous for an observer and not simultaneous for another one, even when both observers are located in the same reference frame. Most of the students surveyed cannot give an answer only depending on the location of the observer when his/her velocity is mentioned as if the movement contaminated the event. This lack of understanding is embodied in reasoning implemented by the population surveyed to address classical kinematics questions and seems to form a major obstacle to grasping relativistic kinematics.
15. Frontal eye fields involved in shifting frame of reference within working memory for scenes
DEFF Research Database (Denmark)
Wallentin, Mikkel; Roepstorff, Andreas; Burgess, Neil
2008-01-01
Working memory (WM) evoked by linguistic cues for allocentric spatial and egocentric spatial aspects of a visual scene was investigated by correlating fMRI BOLD signal (or "activation") with performance on a spatial-relations task. Subjects indicated the relative positions of a person or object...... (referenced by the personal pronouns "he/she/it") in a previously-shown image relative to either themselves (egocentric reference frame) or shifted to a reference frame anchored in another person or object in the image (allocentric reference frame), e.g. "Was he in front of you/her?" Good performers had both...... shorter response time and more correct responses than poor performers in both tasks. These behavioural variables were entered into a principal component analysis. The first component reflected generalised performance level. We found that the frontal eye fields (FEF), bilaterally, had a higher BOLD...
16. Spatial Frames of Reference in Traditional Negev Arabic: Language-to-Cognition Correlation.
Science.gov (United States)
Cerqueglini, Letizia
2015-09-01
Linguistic and cognitive tasks on spatial Frames of Reference (FoRs) in Traditional Negev Arabic (TNA) show that TNA is a referentially promiscuous language, using Intrinsic, Relative and Absolute FoRs. FoRs are selected in context according to culture-specific features of the ground (G). TNA speakers exclusively use the Absolute FoR in cognitive tasks, similarly to Mesoamerican languages (Bohnemeyer et al. in Proceedings of the 36th Annual Conference of the Cognitive Science Society, Austin, 2014). Absolute FoR in TNA is anchored on the four cardinal directions. Nevertheless, in TNA and in other varieties of Nomadic Arabic, geocentric sub-types of the Absolute FoR are also observable. Indeed, as in other Absolute-framing systems worldwide, different anchoring strategies (geocentric and astronomic) tend to coexist. I define their coexistence "Absolute Referential Modularity" (ARM). ARM appears in TNA in cognitive referential tasks and in some lexical items, not in linguistic tasks (as elaborated by Levinson et al. in Space stimuli kit 1.2: November 1992. Max Planck Institute for Psycholinguistics, Nijmegen, pp 7-14, 1992). Cardinal directions across Nomadic Arabic varieties show great cultural salience. They are associated with concrete geographical elements and encode topological relations: east-west axis encodes the mountain-sea opposition, beside many symbolic meanings, and encodes the oppositions Up/Down and Inside (familiar)/Outside (foreign). The detection of cognitive and linguistic Absolute referential practices-characterized by Modularity-and the cultural salience of cardinal directions within the whole Nomadic Arabic linguistic group, support the bias for Absolute cognition in promiscuous systems and its antecedence with respect to later linguistic referential strategies (Bohnemeyer et al. 2014). TNA linguistic promiscuity represents an innovation with respect to the cognitive concepts and demonstrates that language first generates semantic structures
17. Berry's phase factors in moving frames of reference and their observable effects
International Nuclear Information System (INIS)
Sun Changpu; Zhang Linzhi
1990-01-01
Under non-relativistic conditions, the properties of adiabatic solutions of the Schroedinger equation in moving frame of reference and the behaviours of the corresponding Berry's Phase are analysed. Two cases of translation and rotation are discussed in detail, which show that the existence of Berry's phase depends on the choice of frame of reference. While Bitter and Dubbers's experiment is explained by the first-order approximation in the discussion. The non-adiabatic effects in this experiment are predicted by the second-order approximation when the adiabatic condition is broken
18. Decoherence-full subsystems and the cryptographic power of a private shared reference frame
International Nuclear Information System (INIS)
Bartlett, Stephen D.; Rudolph, Terry; Spekkens, Robert W.
2004-01-01
We show that private shared reference frames can be used to perform private quantum and private classical communication over a public quantum channel. Such frames constitute a type of private shared correlation, distinct from private classical keys or shared entanglement, useful for cryptography. We present optimally efficient schemes for private quantum and classical communication given a finite number of qubits transmitted over an insecure channel and given a private shared Cartesian frame and/or a private shared reference ordering of the qubits. We show that in this context, it is useful to introduce the concept of a decoherence-full subsystem, wherein every state is mapped to the completely mixed state under the action of the decoherence
19. Asymptotically Matched Layer (AML) for transient wave propagation in a moving frame of reference
DEFF Research Database (Denmark)
2017-01-01
The paper presents an Asymptotically Matched Layer (AML) formulation in a moving frame of reference for transient dynamic response of a multi-layer 2D half-space. A displacement based finite element formulation of the convected domain problem is presented together with the AML formulation in whic...
20. Understanding Frame-of-Reference Training Success: A Social Learning Theory Perspective
Science.gov (United States)
Sulsky, Lorne M.; Kline, Theresa J. B.
2007-01-01
Employing the social learning theory (SLT) perspective on training, we analysed the effects of alternative frame-of-reference (FOR) training protocols on various criteria of training effectiveness. Undergraduate participants (N = 65) were randomly assigned to one of four FOR training conditions and a control condition. Training effectiveness was…
1. The values underlying the Draft Common Frame of Reference: what role for fairness and 'social justice'?
NARCIS (Netherlands)
2008-01-01
This study provides an in-depth analysis of the provisions of the draft Common Frame of Reference (DCFR), in order to assess if the DCFR perceives contract law only as a tool for regulating private law relations between equally strong parties or if it contains elements of 'social justice' in favour
2. The draft common frame of reference (DCFR) : A giant with feet of clay
NARCIS (Netherlands)
Chirico, F.; van Damme, E.E.C.; Larouche, P.; Larouche, P.; Cserne, P.
2013-01-01
This chapter summarizes the lessons drawn from the work of the Economic Impact Group (EIG), a part of the CoPECL Network of Excellence funded by the EU to prepare a Draft Common Frame of Reference (DCFR). First, it revisits basic principles which are central to the work of the whole group. For one,
3. The Generalized Internal/External Frame of Reference Model: An Extension to Dimensional Comparison Theory
Science.gov (United States)
Möller, Jens; Müller-Kalthoff, Hanno; Helm, Friederike; Nagy, Nicole; Marsh, Herb W.
2016-01-01
The dimensional comparison theory (DCT) focuses on the effects of internal, dimensional comparisons (e.g., "How good am I in math compared to English?") on academic self-concepts with widespread consequences for students' self-evaluation, motivation, and behavioral choices. DCT is based on the internal/external frame of reference model…
4. Location memory biases reveal the challenges of coordinating visual and kinesthetic reference frames
Science.gov (United States)
Simmering, Vanessa R.; Peterson, Clayton; Darling, Warren; Spencer, John P.
2008-01-01
Five experiments explored the influence of visual and kinesthetic/proprioceptive reference frames on location memory. Experiments 1 and 2 compared visual and kinesthetic reference frames in a memory task using visually-specified locations and a visually-guided response. When the environment was visible, results replicated previous findings of biases away from the midline symmetry axis of the task space, with stability for targets aligned with this axis. When the environment was not visible, results showed some evidence of bias away from a kinesthetically-specified midline (trunk anterior–posterior [a–p] axis), but there was little evidence of stability when targets were aligned with body midline. This lack of stability may reflect the challenges of coordinating visual and kinesthetic information in the absence of an environmental reference frame. Thus, Experiments 3–5 examined kinesthetic guidance of hand movement to kinesthetically-defined targets. Performance in these experiments was generally accurate with no evidence of consistent biases away from the trunk a–p axis. We discuss these results in the context of the challenges of coordinating reference frames within versus between multiple sensori-motor systems. PMID:17703284
5. Does Environmental Experience Shape Spatial Cognition? Frames of Reference among Ancash Quechua Speakers (Peru)
Science.gov (United States)
Shapero, Joshua A.
2017-01-01
Previous studies have shown that language contributes to humans' ability to orient using landmarks and shapes their use of frames of reference (FoRs) for memory. However, the role of environmental experience in shaping spatial cognition has not been investigated. This study addresses such a possibility by examining the use of FoRs in a nonverbal…
6. Quantum mechanics in noninertial reference frames: Violations of the nonrelativistic equivalence principle
International Nuclear Information System (INIS)
2014-01-01
In previous work we have developed a formulation of quantum mechanics in non-inertial reference frames. This formulation is grounded in a class of unitary cocycle representations of what we have called the Galilean line group, the generalization of the Galilei group that includes transformations amongst non-inertial reference frames. These representations show that in quantum mechanics, just as is the case in classical mechanics, the transformations to accelerating reference frames give rise to fictitious forces. A special feature of these previously constructed representations is that they all respect the non-relativistic equivalence principle, wherein the fictitious forces associated with linear acceleration can equivalently be described by gravitational forces. In this paper we exhibit a large class of cocycle representations of the Galilean line group that violate the equivalence principle. Nevertheless the classical mechanics analogue of these cocycle representations all respect the equivalence principle. -- Highlights: •A formulation of Galilean quantum mechanics in non-inertial reference frames is given. •The key concept is the Galilean line group, an infinite dimensional group. •A large class of general cocycle representations of the Galilean line group is constructed. •These representations show violations of the equivalence principle at the quantum level. •At the classical limit, no violations of the equivalence principle are detected
7. Somali refugees' experiences with their general practitioners: frames of reference and critical episodes.
NARCIS (Netherlands)
Feldmann, C.T.; Bensing, J.M.; Ruijter, A. de; Boeije, H.R.
2006-01-01
The article presents the results of a qualitative study based on in-depth interviews with Somali refugees living in The Netherlands, on their experiences with general practitioners (GPs). The central question is: what are the frames of reference participants use to interpret their experiences? The
8. Somali refugees’ experiences with their general practitioners: frames of reference and critical episodes
NARCIS (Netherlands)
Titia Feldmann, C.; Bensing, J.; Ruijter, Arie de; Boeije, H.R.
2006-01-01
The article presents the results of a qualitative study based on in-depth interviews with Somali refugees living in The Netherlands, on their experiences with general practitioners (GPs). The central question is: what are the frames of reference participants use to interpret their experiences? The
9. Operationalization of a Frame of Reference for Studying Organizational Culture in Middle Schools.
Science.gov (United States)
Daniel, Larry G.
A frame of reference for studying culture in middle schools was developed. Items for the Middle School Description Survey (MSDS), which was designed to test elements of the ideal middle school culture, were created based on middle school advocacy literature. The items were conceptually categorized according to E. H. Schein's (1985) cultural…
10. A global vertical reference frame based on four regional vertical datums
Czech Academy of Sciences Publication Activity Database
Burša, Milan; Kenyon, S.; Kouba, J.; Šíma, Zdislav; Vatrt, V.; Vojtíšková, M.
2004-01-01
Roč. 48, č. 3 (2004), s. 493-502 ISSN 0039-3169 Institutional research plan: CEZ:AV0Z1003909 Keywords : geopotentinal * local vertical datums * global vertical reference frame Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 0.447, year: 2004
11. Conventional Synchronous Reference Frame Phase-Locked Loop Is An Adaptive Complex Filter
DEFF Research Database (Denmark)
Golestan, Saeed; Guerrero, Josep M.
2015-01-01
Despite the wide acceptance and use of the conventional synchronous reference frame phase-locked loop (SRFPLL) no transfer function describing its actual input-output relationship has been developed so far. Arguably, the absence of such transfer function has hampered the application of SRF...
12. Consistent Feature Extraction From Vector Fields: Combinatorial Representations and Analysis Under Local Reference Frames
Energy Technology Data Exchange (ETDEWEB)
Bhatia, Harsh [Univ. of Utah, Salt Lake City, UT (United States)
2015-05-01
This dissertation presents research on addressing some of the contemporary challenges in the analysis of vector fields—an important type of scientific data useful for representing a multitude of physical phenomena, such as wind flow and ocean currents. In particular, new theories and computational frameworks to enable consistent feature extraction from vector fields are presented. One of the most fundamental challenges in the analysis of vector fields is that their features are defined with respect to reference frames. Unfortunately, there is no single “correct” reference frame for analysis, and an unsuitable frame may cause features of interest to remain undetected, thus creating serious physical consequences. This work develops new reference frames that enable extraction of localized features that other techniques and frames fail to detect. As a result, these reference frames objectify the notion of “correctness” of features for certain goals by revealing the phenomena of importance from the underlying data. An important consequence of using these local frames is that the analysis of unsteady (time-varying) vector fields can be reduced to the analysis of sequences of steady (timeindependent) vector fields, which can be performed using simpler and scalable techniques that allow better data management by accessing the data on a per-time-step basis. Nevertheless, the state-of-the-art analysis of steady vector fields is not robust, as most techniques are numerical in nature. The residing numerical errors can violate consistency with the underlying theory by breaching important fundamental laws, which may lead to serious physical consequences. This dissertation considers consistency as the most fundamental characteristic of computational analysis that must always be preserved, and presents a new discrete theory that uses combinatorial representations and algorithms to provide consistency guarantees during vector field analysis along with the uncertainty
13. Technical Note: Modification of the standard gain correction algorithm to compensate for the number of used reference flat frames in detector performance studies
International Nuclear Information System (INIS)
Konstantinidis, Anastasios C.; Olivo, Alessandro; Speller, Robert D.
2011-01-01
Purpose: The x-ray performance evaluation of digital x-ray detectors is based on the calculation of the modulation transfer function (MTF), the noise power spectrum (NPS), and the resultant detective quantum efficiency (DQE). The flat images used for the extraction of the NPS should not contain any fixed pattern noise (FPN) to avoid contamination from nonstochastic processes. The ''gold standard'' method used for the reduction of the FPN (i.e., the different gain between pixels) in linear x-ray detectors is based on normalization with an average reference flat-field. However, the noise in the corrected image depends on the number of flat frames used for the average flat image. The aim of this study is to modify the standard gain correction algorithm to make it independent on the used reference flat frames. Methods: Many publications suggest the use of 10-16 reference flat frames, while other studies use higher numbers (e.g., 48 frames) to reduce the propagated noise from the average flat image. This study quantifies experimentally the effect of the number of used reference flat frames on the NPS and DQE values and appropriately modifies the gain correction algorithm to compensate for this effect. Results: It is shown that using the suggested gain correction algorithm a minimum number of reference flat frames (i.e., down to one frame) can be used to eliminate the FPN from the raw flat image. This saves computer memory and time during the x-ray performance evaluation. Conclusions: The authors show that the method presented in the study (a) leads to the maximum DQE value that one would have by using the conventional method and very large number of frames and (b) has been compared to an independent gain correction method based on the subtraction of flat-field images, leading to identical DQE values. They believe this provides robust validation of the proposed method.
14. The use of the empirical mode decomposition for the identification of mean field aligned reference frames
Directory of Open Access Journals (Sweden)
Mauro Regi
2017-01-01
Full Text Available The magnetic field satellite data are usually referred to geocentric coordinate reference frame. Conversely, the magnetohydrodynamic waves modes in magnetized plasma depend on the ambient magnetic field, and is then useful to rotate the magnetic field measurements into the mean field aligned (MFA coordinate system. This reference frame is useful to study the ultra low frequency magnetic field variations along the direction of the mean field and perpendicularly to it. In order to identify the mean magnetic field the classical moving average (MAVG approach is usually adopted but, under particular conditions, this procedure induces undesired features, such as spectral alteration in the rotated components. We discuss these aspects promoting an alternative and more efficient method for mean field aligned projection, based on the empirical mode decomposition (EMD.
15. A Ka-Band Celestial Reference Frame with Applications to Deep Space Navigation
Science.gov (United States)
Jacobs, Christopher S.; Clark, J. Eric; Garcia-Miro, Cristina; Horiuchi, Shinji; Sotuela, Ioana
2011-01-01
The Ka-band radio spectrum is now being used for a wide variety of applications. This paper highlights the use of Ka-band as a frequency for precise deep space navigation based on a set of reference beacons provided by extragalactic quasars which emit broadband noise at Ka-band. This quasar-based celestial reference frame is constructed using X/Ka-band (8.4/32 GHz) from fifty-five 24-hour sessions with the Deep Space Network antennas in California, Australia, and Spain. We report on observations which have detected 464 sources covering the full 24 hours of Right Ascension and declinations down to -45 deg. Comparison of this X/Ka-band frame to the international standard S/X-band (2.3/8.4 GHz) ICRF2 shows wRMS agreement of approximately 200 micro-arcsec in alpha cos(delta) and approximately 300 micro-arcsec in delta. There is evidence for systematic errors at the 100 micro-arcsec level. Known errors include limited SNR, lack of instrumental phase calibration, tropospheric refraction mis-modeling, and limited southern geometry. The motivation for extending the celestial reference frame to frequencies above 8 GHz is to access more compact source morphology for improved frame stability and to support spacecraft navigation for Ka-band based NASA missions.
16. The Gaia inertial reference frame and the tilting of the Milky Way disk
International Nuclear Information System (INIS)
Perryman, Michael; Spergel, David N.; Lindegren, Lennart
2014-01-01
While the precise relationship between the Milky Way disk and the symmetry planes of the dark matter halo remains somewhat uncertain, a time-varying disk orientation with respect to an inertial reference frame seems probable. Hierarchical structure formation models predict that the dark matter halo is triaxial and tumbles with a characteristic rate of ∼2 rad H 0 −1 (∼30 μas yr –1 ). These models also predict a time-dependent accretion of gas, such that the angular momentum vector of the disk should be misaligned with that of the halo. These effects, as well as tidal effects of the LMC, will result in the rotation of the angular momentum vector of the disk population with respect to the quasar reference frame. We assess the accuracy with which the positions and proper motions from Gaia can be referred to a kinematically non-rotating system, and show that the spin vector of the transformation from any rigid self-consistent catalog frame to the quasi-inertial system defined by quasars should be defined to better than 1 μas yr –1 . Determination of this inertial frame by Gaia will reveal any signature of the disk orientation varying with time, improve models of the potential and dynamics of the Milky Way, test theories of gravity, and provide new insights into the orbital evolution of the Sagittarius dwarf galaxy and the Magellanic Clouds.
17. Is physics in the infinite momentum frame independent of the compactificaction radius?
International Nuclear Information System (INIS)
Gueijosa, A.
1998-01-01
With the aim of clarifying the eleven-dimensional content of matrix theory, we examine the dependence of a theory in the infinite momentum frame (IMF) on the (purely spatial) longitudinal compactification radius R. It is shown that in a point particle theory the generic scattering amplitude becomes independent of R in the IMF. Processes with zero longitudinal momentum transfer are found to be exceptional. The same question is addressed in a theory with extended objects. A one-loop type II string amplitude is shown to be R-independent in the IMF, and to coincide with that of the uncompactified theory. No exceptional processes exist in this case. The possible implications of these results for M theory are discussed. In particular, if amplitudes in M theory are independent of R in the IMF, matrix theory can be rightfully expected (in the N→∞ limit) to describe uncompactified M theory. (orig.)
18. Hybrid state‐space time integration in a rotating frame of reference
DEFF Research Database (Denmark)
Krenk, Steen; Nielsen, Martin Bjerre
2011-01-01
displacements and the global velocities are represented by the same shape functions. This leads to a simple generalization of the corresponding equations of motion in a stationary frame in which all inertial effects are represented via the classic global mass matrix. The formulation introduces two gyroscopic......A time integration algorithm is developed for the equations of motion of a flexible body in a rotating frame of reference. The equations are formulated in a hybrid state‐space, formed by the local displacement components and the global velocity components. In the spatial discretization the local...... terms, while the centrifugal forces are represented implicitly via the hybrid state‐space format. An angular momentum and energy conserving algorithm is developed, in which the angular velocity of the frame is represented by its mean value. A consistent algorithmic damping scheme is identified...
19. An accelerating reference frame for electromagnetic waves in a rapidly growing plasma
International Nuclear Information System (INIS)
Yablonovitch, E.
1989-01-01
In 1974, Hawking showed that black holes can evaporate by the emission of low temperature thermal radiation, now named Hawking radiation. Shortly thereafter, a closely related effect called Unruh radiation became apparent. The author discusses how, according to Unruh and Davies, observers of the electromagnetic field in an accelerating reference frame should see thermal radiation at a temperature T: KT = h/2π a/c where a is the acceleration relative to an inertial frame, c is the speed of light and h and K are Planck's and Boltzmann's constant respectively. In a frame accelerating at g = 980 cm/sec 2 , equivalent to the acceleration experienced at the earth's surface, this thermal radiation is at a temperature of only 4 x 10 -20 degrees K. Therefore, physicists hoping to observe this radiation, have sought out systems being subjected to extreme acceleration
20. How Flexible is the Use of Egocentric Versus Allocentric Frame of Reference in the Williams Syndrome Population?
Science.gov (United States)
Heiz, J; Majerus, S; Barisnikov, K
2017-09-28
This study examined the spontaneous use of allocentric and egocentric frames of reference and their flexible use as a function of instructions. The computerized spatial reference task created by Heiz and Barisnikov (2015) was used. Participants had to choose a frame of reference according to three types of instructions: spontaneous, allocentric and egocentric. The performances of 16 Williams Syndrome participants between 10 and 41 years were compared to those of two control groups (chronological age and non-verbal intellectual ability). The majority of Williams Syndrome participants did not show a preference for a particular frame of reference. When explicitly inviting participants to use an allocentric frame of reference, all three groups showed an increased use of the allocentric frame of reference. At the same time, an important heterogeneity of type of frame of reference used by Williams Syndrome participants was observed. Results demonstrate that despite difficulties in the spontaneous use of allocentric and egocentric frames of reference, some Williams Syndrome participants show flexibility in the use of an allocentric frame of reference when an explicit instruction is provided. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
1. Classical field theory in the space of reference frames. [Space-time manifold, action principle
Energy Technology Data Exchange (ETDEWEB)
Toller, M [Dipartimento di Matematica e Fisica, Libera Universita, Trento (Italy)
1978-03-11
The formalism of classical field theory is generalized by replacing the space-time manifold M by the ten-dimensional manifold S of all the local reference frames. The geometry of the manifold S is determined by ten vector fields corresponding to ten operationally defined infinitesimal transformations of the reference frames. The action principle is written in terms of a differential 4-form in the space S (the Lagrangian form). Densities and currents are represented by differential 3-forms in S. The field equations and the connection between symmetries and conservation laws (Noether's theorem) are derived from the action principle. Einstein's theory of gravitation and Maxwell's theory of electromagnetism are reformulated in this language. The general formalism can also be used to formulate theories in which charge, energy and momentum cannot be localized in space-time and even theories in which a space-time manifold cannot be defined exactly in any useful way.
2. The perspective matters! Multisensory integration in ego-centric reference frames determines full body ownership
Directory of Open Access Journals (Sweden)
Valeria Ivanova Petkova
2011-03-01
Full Text Available Recent advances in experimental science have made it possible to investigate the perceptual processes involved in generating a sense of owning an entire body. This is achieved by full-body ownership illusions which make use of specific patterns of visual and somatic stimuli integration. Here we investigate the fundamental question of the reference frames used in the process of attributing an entire body to the self. We quantified the strength of the body-swap illusion in conditions where the participants were observing this artificial body from the perspective of the first or third person. Consistent results from subjective reports and physiological recordings show that the first person visual perspective is critical for the induction of this full-body ownership illusion. This demonstrates that the multisensory integration processes producing the sense of corporeal self operates in an ego-centric reference frame.
3. The Perspective Matters! Multisensory Integration in Ego-Centric Reference Frames Determines Full-Body Ownership
Science.gov (United States)
Petkova, Valeria I.; Khoshnevis, Mehrnoush; Ehrsson, H. Henrik
2011-01-01
Recent advances in experimental science have made it possible to investigate the perceptual processes involved in generating a sense of owning an entire body. This is achieved by full-body ownership illusions which make use of specific patterns of visual and somatic stimuli integration. Here we investigate the fundamental question of the reference frames used in the process of attributing an entire body to the self. We quantified the strength of the body-swap illusion in conditions where the participants were observing this artificial body from the perspective of the first or third person. Consistent results from subjective reports and physiological recordings show that the first person visual perspective is critical for the induction of this full-body ownership illusion. This demonstrates that the multisensory integration processes producing the sense of corporeal self operates in an ego-centric reference frame. PMID:21687436
4. Frames of Reference: A Metaphor for Analyzing and Interpreting Attitudes of Environmental Policy Makers and Policy Influencers
Science.gov (United States)
Swaffield
1998-07-01
/ The concept of frame of reference offers a potentially useful analytical metaphor in environmental management. This is illustrated by a case study in which attitudes of individuals involved in the management of trees in the New Zealand high country are classified into seven distinctive frames of reference. Some practical and theoretical implications of the use of the frame metaphor are explored, including its potential contribution to the emerg- ing field of communicative planning. KEY WORDS: Frames of reference; Environmental policy analysis; Metaphor; New Zealand high country
5. Extension of the PSE code NOLOT for transition analysis in rotating reference frames
OpenAIRE
Dechamps, Xavier; Hein, Stefan
2016-01-01
The present work aims at contributing to a better understanding of the effect of rotation on the stability properties of boundary layers. For this purpose, the Parabolized-Stability-Equations based NOLOT code was extended to rotating reference frames through the inclusion of the centrifugal and Coriolis forces. Stability analyses of three flow configurations were then considered for verification: the rotating Blasius Profile, the flow along a curved wall and the three-dimensional flow due to ...
6. Early visual deprivation prompts the use of body-centered frames of reference for auditory localization.
Science.gov (United States)
Vercillo, Tiziana; Tonelli, Alessia; Gori, Monica
2018-01-01
The effects of early visual deprivation on auditory spatial processing are controversial. Results from recent psychophysical studies show that people who were born blind have a spatial impairment in localizing sound sources within specific auditory settings, while previous psychophysical studies revealed enhanced auditory spatial abilities in early blind compared to sighted individuals. An explanation of why an auditory spatial deficit is sometimes observed within blind populations and its task-dependency remains to be clarified. We investigated auditory spatial perception in early blind adults and demonstrated that the deficit derives from blind individual's reduced ability to remap sound locations using an external frame of reference. We found that performance in blind population was severely impaired when they were required to localize brief auditory stimuli with respect to external acoustic landmarks (external reference frame) or when they had to reproduce the spatial distance between two sounds. However, they performed similarly to sighted controls when had to localize sounds with respect to their own hand (body-centered reference frame), or to judge the distances of sounds from their finger. These results suggest that early visual deprivation and the lack of visual contextual cues during the critical period induce a preference for body-centered over external spatial auditory representations. Copyright © 2017 Elsevier B.V. All rights reserved.
7. Navigation accuracy comparing non-covered frame and use of plastic sterile drapes to cover the reference frame in 3D acquisition.
Science.gov (United States)
Corenman, Donald S; Strauch, Eric L; Dornan, Grant J; Otterstrom, Eric; Zalepa King, Lisa
2017-09-01
Advancements in surgical navigation technology coupled with 3-dimensional (3D) radiographic data have significantly enhanced the accuracy and efficiency of spinal fusion implant placement. Increased usage of such technology has led to rising concerns regarding maintenance of the sterile field, as makeshift drape systems are fraught with breaches thus presenting increased risk of surgical site infections (SSIs). A clinical need exists for a sterile draping solution with these techniques. Our objective was to quantify expected accuracy error associated with 2MM and 4MM thickness Sterile-Z Patient Drape ® using Medtronic O-Arm ® Surgical Imaging with StealthStation ® S7 ® Navigation System. Camera distance to reference frame was investigated for contribution to accuracy error. A testing jig was placed on the radiolucent table and the Medtronic passive reference frame was attached to jig. The StealthStation ® S7 ® navigation camera was placed at various distances from testing jig and the geometry error of reference frame was captured for three different drape configurations: no drape, 2MM drape and 4MM drape. The O-Arm ® gantry location and StealthStation ® S7 ® camera position was maintained and seven 3D acquisitions for each of drape configurations were measured. Data was analyzed by a two-factor analysis of variance (ANOVA) and Bonferroni comparisons were used to assess the independent effects of camera angle and drape on accuracy error. Median (and maximum) measurement accuracy error was higher for the 2MM than for the 4MM drape for each camera distance. The most extreme error observed (4.6 mm) occurred when using the 2MM and the 'far' camera distance. The 4MM drape was found to induce an accuracy error of 0.11 mm (95% confidence interval, 0.06-0.15; P<0.001) relative to the no drape testing, regardless of camera distance. Medium camera distance produced lower accuracy error than either the close (additional 0.08 mm error; 95% CI, 0-0.15; P=0.035) or far
8. Micro-arcsecond Celestial Reference Frames: definition and realization — Impact of the recent IAU Resolutions
International Nuclear Information System (INIS)
Capitaine, Nicole
2012-01-01
The adoption of the International Celestial Reference System (ICRS), based on Very Long Baseline Interferometry (VLBI) observations of extragalactic radiosources by the International Astronomical Union (IAU) since 1998 January 1, opened a new era for astronomy. The ICRS and the corresponding frame, the International Celestial Reference Frame (ICRF), replaced the Fundamental Catalog (FK5) based on positions and proper motions of bright stars, with the Hipparcos catalog being adopted as the primary realization of the ICRS in optical wavelengths. According to its definition, the ICRS is such that the barycentric directions of distant extragalactic objects show no global rotation with respect to these objects; this provides a quasi-inertial reference for measuring the positions and angular motions of the celestial objects. Other resolutions on reference systems were passed by the IAU in 2000 and 2006 and endorsed by the International Union of Geodesy and Geophysics (IUGG) in 2003 and 2007, respectively. These especially concern the definition and realization of the astronomical reference systems in the framework of general relativity and transformations between them. First, the IAU 2000 resolutions refined the concepts and definition of the astronomical reference systems and parameters for Earth's rotation, and adopted the IAU 2000 precession-nutation. Then, the IAU 2006 resolutions adopted a new precession model that is consistent with dynamical theories; they also addressed definition, terminology or orientation issues relative to reference systems and time scales that needed to be specified after the adoption of the IAU 2000 resolutions. An additional IUGG 2007 resolution defined the International Terrestrial Reference System (ITRS) so that it strictly complies with the IAU recommendations. Finally, the IAU 2009 resolutions adopted a new system of astronomical constants and an improved realization of the ICRF. These fundamental changes have led to significant
9. The Influence of the Terrestrial Reference Frame on Studies of Sea Level Change
Science.gov (United States)
Nerem, R. S.; Bar-Sever, Y. E.; Haines, B. J.; Desai, S.; Heflin, M. B.
2015-12-01
The terrestrial reference frame (TRF) provides the foundation for the accurate monitoring of sea level using both ground-based (tide gauges) and space-based (satellite altimetry) techniques. For the latter, tide gauges are also used to monitor drifts in the satellite instruments over time. The accuracy of the terrestrial reference frame (TRF) is thus a critical component for both types of sea level measurements. The TRF is central to the formation of geocentric sea-surface height (SSH) measurements from satellite altimeter data. The computed satellite orbits are linked to a particular TRF via the assumed locations of the ground-based tracking systems. The manner in which TRF errors are expressed in the orbit solution (and thus SSH) is not straightforward, and depends on the models of the forces underlying the satellite's motion. We discuss this relationship, and provide examples of the systematic TRF-induced errors in the altimeter derived sea-level record. The TRF is also crucial to the interpretation of tide-gauge measurements, as it enables the separation of vertical land motion from volumetric changes in the water level. TRF errors affect tide gauge measurements through GNSS estimates of the vertical land motion at each tide gauge. This talk will discuss the current accuracy of the TRF and how errors in the TRF impact both satellite altimeter and tide gauge sea level measurements. We will also discuss simulations of how the proposed Geodetic Reference Antenna in SPace (GRASP) satellite mission could reduce these errors and revolutionize how reference frames are computed in general.
10. The irreducible needs of children for development: a frame of reference to health care
Directory of Open Access Journals (Sweden)
Maria De La Ó Ramallo Veríssimo
2018-03-01
Full Text Available ABSTRACT A comprehensive health care to children implies in caring for their development, by perceiving the needs based on a suitable reference to children’s specificities. This theoretical study aimed to analyze the “irreducible needs of children” frame of reference, based on a child development theory. We performed a comparative analysis between the contents of children’s irreducible needs and the components of the Bioecological Theory of Human Development. An extensive correspondence was verified among the components of the Bioecological Theory and the following essential needs: ongoing nurturing relationships; experiences tailored to individual differences; developmentally appropriate experiences; limit setting, structure and expectations; stable, supportive communities and cultural continuity. The need for physical protection, safety, and regulation is not explicit in the elements of the theory, although it is also verified in their definitions. We concluded that the irreducible needs’ reference can support nurses in health care and in child development promotion.
11. Formal structures, the concepts of covariance, invariance, equivalent reference frames, and the principle Relativity
Science.gov (United States)
Rodrigues, W. A.; Scanavini, M. E. F.; de Alcantara, L. P.
1990-02-01
In this paper a given spacetime theory T is characterized as the theory of a certain species of structure in the sense of Bourbaki [1]. It is then possible to clarify in a rigorous way the concepts of passive and active covariance of T under the action of the manifold mapping group G M . For each T, we define also an invariance group G I T and, in general, G I T ≠ G M . This group is defined once we realize that, for each τ ∈ ModT, each explicit geometrical object defining the structure can be classified as absolute or dynamical [2]. All spacetime theories possess also implicit geometrical objects that do not appear explicitly in the structure. These implicit objects are not absolute nor dynamical. Among them there are the reference frame fields, i.e., “timelike” vector fields X ∈ TU,U subseteq M M, where M is a manifold which is part of ST, a substructure for each τ ∈ ModT, called spacetime. We give a physically motivated definition of equivalent reference frames and introduce the concept of the equivalence group of a class of reference frames of kind X according to T, G X T. We define that T admits a weak principle of relativity (WPR) only if G X T ≠ identity for some X. If G X T = G I T for some X, we say that T admits a strong principle of relativity (PR). The results of this paper generalize and clarify several results obtained by Anderson [2], Scheibe [3], Hiskes [4], Recami and Rodrigues [5], Friedman [6], Fock [7], and Scanavini [8]. Among the novelties here, there is the realization that the definitions of G I T and G X T can be given only when certain boundary conditions for the equations of motion of T can be physically realizable in the domain U U subseteq M M, where a given reference frame is defined. The existence of physically realizable boundary conditions for each τ ∈ ModT (in ∂ U), in contrast with the mathematically possible boundary condition, is then seen to be essential for the validity of a principle of relativity for T
12. The role of spatial memory and frames of reference in the precision of angular path integration.
Science.gov (United States)
Arthur, Joeanna C; Philbeck, John W; Kleene, Nicholas J; Chichka, David
2012-09-01
Angular path integration refers to the ability to maintain an estimate of self-location after a rotational displacement by integrating internally-generated (idiothetic) self-motion signals over time. Previous work has found that non-sensory inputs, namely spatial memory, can play a powerful role in angular path integration (Arthur et al., 2007, 2009). Here we investigated the conditions under which spatial memory facilitates angular path integration. We hypothesized that the benefit of spatial memory is particularly likely in spatial updating tasks in which one's self-location estimate is referenced to external space. To test this idea, we administered passive, non-visual body rotations (ranging 40°-140°) about the yaw axis and asked participants to use verbal reports or open-loop manual pointing to indicate the magnitude of the rotation. Prior to some trials, previews of the surrounding environment were given. We found that when participants adopted an egocentric frame of reference, the previously-observed benefit of previews on within-subject response precision was not manifested, regardless of whether remembered spatial frameworks were derived from vision or spatial language. We conclude that the powerful effect of spatial memory is dependent on one's frame of reference during self-motion updating. Copyright © 2012 Elsevier B.V. All rights reserved.
13. A novel quasi-master-slave control frame for PV-storage independent microgrid
DEFF Research Database (Denmark)
Yang, Jian; Yuan, Wenbin; Sun, Yao
2018-01-01
In microgrid, photovoltaic (PV) and storage are always combined as a droop-controlled ideal source, which is not very practical. Alternatively, this paper introduces a PV-storage independent system via allocating the PV-storage separately. For this structure, a novel quasi-master-slave control...... frame is proposed without communication. Storages work as master voltage sources, and PVs operate as current controlled voltage sources (CCVS). For the slave PVs, a MPPT-based power droop control and an adaptive reactive power control are proposed. Thus, PVs can simultaneously achieve maximum energy...... is analyzed to design the physical and control parameters, such as, the minimum capacitance value of DC side, droop coefficients. Finally, simulation and experimental results are presented to verify the system effectiveness....
14. Hydrodynamical expansion with frame independence symmetry in high energy multiparticle production
International Nuclear Information System (INIS)
Chiu, C.B.; Sudarshan, E.C.G.; Wang, K.
1974-01-01
The space--time development of the hadronic system formed immediately after the high energy hadron collision is described with the following picture. Initially the system is highly compressed along the longitudinal direction. The sudden relaxation of this compression leads to a violent acceleration along this direction and perhaps a weak acceleration along the transverse direction. When these accelerations cease, it is proposed that the system acquires a frame independence symmetry with its further expansion governed by the hydrodynamic equation of motion. Within the scheme, this symmetry provides a natural mechanism which eventually leads to a flat inclusive longitudinal rapidity distribution and it also admits a sharp cutoff in the inclusive transverse momentum distribution. The latter is to be contrasted with the prediction of Landau's model, where the average transverse momentum increases with c.m. energy W, [p/sub T/] -W/sup 1 / 6 ./. Finally effects of clustering can also be easily incorporated within the framework. (U.S.)
15. Hydrodynamical expansion with frame-independence symmetry in high-energy multiparticle production
International Nuclear Information System (INIS)
Chiu, C.B.; Sudarshan, E.; Wang, K.
1975-01-01
We describe the space-time development of the hardronic system formed immediately after the high-energy hadron collision with the following picture. Initially the system is highly compressed along the longitudinal direction. The sudden relaxation of this compression leads to a violent acceration along this direction and perhaps a weak acceleration along the transverse direction. When these accelerations cease, we propose that the system acquires certain frame-independence symmetry with its further expansion governed by the hydrodynamic equation of motion. Within our scheme, this symmetry provides a natural mechanism which eventually leads to a flat inclusive longitudinal rapidity distribution and it also admits a sharp cutoff in the inclusive transverse momentum distribution. These features differ from those of Landau's model
16. OPTICAL SPECTRA OF CANDIDATE INTERNATIONAL CELESTIAL REFERENCE FRAME (ICRF) FLAT-SPECTRUM RADIO SOURCES
Energy Technology Data Exchange (ETDEWEB)
Titov, O.; Stanford, Laura M. [Geoscience Australia, P.O. Box 378, Canberra, ACT 2601 (Australia); Johnston, Helen M.; Hunstead, Richard W. [Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia); Pursimo, T. [Nordic Optical Telescope, Nordic Optical Telescope Apartado 474E-38700 Santa Cruz de La Palma, Santa Cruz de Tenerife (Spain); Jauncey, David L. [CSIRO Astronomy and Space Science, ATNF and Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Maslennikov, K. [Central Astronomical Observatory at Pulkovo, Pulkovskoye Shosse, 65/1, 196140, St. Petersburg (Russian Federation); Boldycheva, A., E-mail: oleg.titov@ga.gov.au [Ioffe Physical Technical Institute, 26 Polytekhnicheskaya, St. Petersburg, 194021 (Russian Federation)
2013-07-01
Continuing our program of spectroscopic observations of International Celestial Reference Frame (ICRF) sources, we present redshifts for 120 quasars and radio galaxies. Data were obtained with five telescopes: the 3.58 m European Southern Observatory New Technology Telescope, the two 8.2 m Gemini telescopes, the 2.5 m Nordic Optical Telescope (NOT), and the 6.0 m Big Azimuthal Telescope of the Special Astrophysical Observatory in Russia. The targets were selected from the International VLBI Service for Geodesy and Astrometry candidate International Celestial Reference Catalog which forms part of an observational very long baseline interferometry (VLBI) program to strengthen the celestial reference frame. We obtained spectra of the potential optical counterparts of more than 150 compact flat-spectrum radio sources, and measured redshifts of 120 emission-line objects, together with 19 BL Lac objects. These identifications add significantly to the precise radio-optical frame tie to be undertaken by Gaia, due to be launched in 2013, and to the existing data available for analyzing source proper motions over the celestial sphere. We show that the distribution of redshifts for ICRF sources is consistent with the much larger sample drawn from Faint Images of the Radio Sky at Twenty cm (FIRST) and Sloan Digital Sky Survey, implying that the ultra-compact VLBI sources are not distinguished from the overall radio-loud quasar population. In addition, we obtained NOT spectra for five radio sources from the FIRST and NRAO VLA Sky Survey catalogs, selected on the basis of their red colors, which yielded three quasars with z > 4.
17. Entanglement and symmetry: A case study in superselection rules, reference frames, and beyond
International Nuclear Information System (INIS)
Jones, S. J.; Wiseman, H. M.; Vaccaro, J. A.; Pope, D. T.; Bartlett, S. D.
2006-01-01
In recent years it has become apparent that constraints on possible quantum operations, such as those constraints imposed by superselection rules (SSRs), have a profound effect on quantum information theoretic concepts like bipartite entanglement. This paper concentrates on a particular example: the constraint that applies when the parties (Alice and Bob) cannot distinguish among certain quantum objects they have. This arises naturally in the context of ensemble quantum information processing such as in liquid NMR. We discuss how a SSR for the symmetric group can be applied, and show how the extractable entanglement can be calculated analytically in certain cases, with a maximum bipartite entanglement in an ensemble of N Bell-state pairs scaling as log(N) as N→∞. We discuss the apparent disparity with the asymptotic (N→∞) recovery of unconstrained entanglement for other sorts of superselection rules, and show that the disparity disappears when the correct notion of applying the symmetric group SSR to multiple copies is used. Next we discuss reference frames in the context of this SSR, showing the relation to the work of von Korff and Kempe [Phys. Rev. Lett. 93, 260502 (2004)]. The action of a reference frame can be regarded as the analog of activation in mixed-state entanglement. We also discuss the analog of distillation: there exist states such that one copy can act as an imperfect reference frame for another copy. Finally we present an example of a stronger operational constraint, that operations must be noncollective as well as symmetric. Even under this stronger constraint we, nevertheless, show that Bell nonlocality (and hence entanglement) can be demonstrated for an ensemble of N Bell-state pairs no matter how large N is. This last work is a generalization of that of Mermin [Phys. Rev. D 22, 356 (1980)
18. Individual differences in the ability to identify, select and use appropriate frames of reference for perceptuo-motor control.
Science.gov (United States)
Isableu, B; Ohlmann, T; Cremieux, J; Vuillerme, N; Amblard, B; Gresty, M A
2010-09-01
The causes of the interindividual differences (IDs) in how we perceive and control spatial orientation are poorly understood. Here, we propose that IDs partly reflect preferred modes of spatial referencing and that these preferences or "styles" are maintained from the level of spatial perception to that of motor control. Two groups of experimental subjects, one with high visual field dependency (FD) and one with marked visual field independency (FI) were identified by the Rod and Frame Test, which identifies relative dependency on a visual frame of reference (VFoR). FD and FI subjects were tasked with standing still in conditions of increasing postural difficulty while visual cues of self-orientation (a visual frame tilted in roll) and self-motion (in stroboscopic illumination) were varied and in darkness to assess visual dependency. Postural stability, overall body orientation and modes of segmental stabilization relative to either external (space) or egocentric (adjacent segments) frames of reference in the roll plane were analysed. We hypothesized that a moderate challenge to balance should enhance subjects' reliance on VFoR, particularly in FD subjects, whereas a substantial challenge should constrain subjects to use a somatic-vestibular based FoR to prevent falling in which case IDs would vanish. The results showed that with increasing difficulty, FD subjects became more unstable and more disoriented shown by larger effects of the tilted visual frame on posture. Furthermore, their preference to coalign body/VFoR coordinate systems lead to greater fixation of the head-trunk articulation and stabilization of the hip in space, whereas the head and trunk remained more stabilized in space with the hip fixed on the leg in FI subjects. These results show that FD subjects have difficulties at identifying and/or adopting a more appropriate FoR based on proprioceptive and vestibular cues to regulate the coalignment of posturo/exocentric FoRs. The FI subjects' resistance
19. Light escape cones in local reference frames of Kerr-de Sitter black hole spacetimes and related black hole shadows
Science.gov (United States)
Stuchlík, Zdeněk; Charbulák, Daniel; Schee, Jan
2018-03-01
We construct the light escape cones of isotropic spot sources of radiation residing in special classes of reference frames in the Kerr-de Sitter (KdS) black hole spacetimes, namely in the fundamental class of non-geodesic' locally non-rotating reference frames (LNRFs), and two classes of geodesic' frames, the radial geodesic frames (RGFs), both falling and escaping, and the frames related to the circular geodesic orbits (CGFs). We compare the cones constructed in a given position for the LNRFs, RGFs, and CGFs. We have shown that the photons locally counter-rotating relative to LNRFs with positive impact parameter and negative covariant energy are confined to the ergosphere region. Finally, we demonstrate that the light escaping cones govern the shadows of black holes located in front of a radiating screen, as seen by the observers in the considered frames. For shadows related to distant static observers the LNRFs are relevant.
20. Optical Spectra of Candidate International Celestial Reference Frame (ICRF) Flat-spectrum Radio Sources. III
Energy Technology Data Exchange (ETDEWEB)
Titov, O.; Stanford, Laura M. [Geoscience Australia, P.O. Box 378, Canberra, ACT 2601 (Australia); Pursimo, T. [Nordic Optical Telescope, Nordic Optical Telescope Apartado 474E-38700 Santa Cruz de La Palma, Santa Cruz de Tenerife (Spain); Johnston, Helen M.; Hunstead, Richard W. [Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia); Jauncey, David L. [CSIRO Astronomy and Space Science, ATNF and Mount Stromlo Observatory, Cotter Road, Weston, ACT 2611 (Australia); Zenere, Katrina A., E-mail: oleg.titov@ga.gov.au [School of Physics, University of Sydney, NSW 2006 (Australia)
2017-04-01
In extending our spectroscopic program, which targets sources drawn from the International Celestial Reference Frame (ICRF) Catalog, we have obtained spectra for ∼160 compact, flat-spectrum radio sources and determined redshifts for 112 quasars and radio galaxies. A further 14 sources with featureless spectra have been classified as BL Lac objects. Spectra were obtained at three telescopes: the 3.58 m European Southern Observatory New Technology Telescope, and the two 8.2 m Gemini telescopes in Hawaii and Chile. While most of the sources are powerful quasars, a significant fraction of radio galaxies is also included from the list of non-defining ICRF radio sources.
1. Enhanced Decoupled Double Synchronous Reference Frame Current Controller for Unbalanced Grid-Voltage Conditions
DEFF Research Database (Denmark)
Reyes, M.; Rodriguez, Pedro; Vazquez, S.
2012-01-01
. In these codes, the injection of positive- and negative-sequence current components becomes necessary for fulfilling, among others, the low-voltage ride-through requirements during balanced and unbalanced grid faults. However, the performance of classical dq current controllers, applied to power converters......, under unbalanced grid-voltage conditions is highly deficient, due to the unavoidable appearance of current oscillations. This paper analyzes the performance of the double synchronous reference frame controller and improves its structure by adding a decoupling network for estimating and compensating...
2. A reference Pelton turbine - High speed visualization in the rotating frame
Science.gov (United States)
Solemslie, Bjørn W.; Dahlhaug, Ole G.
2016-11-01
To enable a detailed study the flow mechanisms effecting the flow within the reference Pelton runner designed at the Waterpower Laboratory (NTNLT) a flow visualization system has been developed. The system enables high speed filming of the hydraulic surface of a single bucket in the rotating frame of reference. It is built with an angular borescopes adapter entering the turbine along the rotational axis and a borescope embedded within a bucket. A stationary high speed camera located outside the turbine housing has been connected to the optical arrangement by a non-contact coupling. The view point of the system includes the whole hydraulic surface of one half of a bucket. The system has been designed to minimize the amount of vibrations and to ensure that the vibrations felt by the borescope are the same as those affecting the camera. The preliminary results captured with the system are promising and enable a detailed study of the flow within the turbine.
3. Out of body, out of space: Impaired reference frame processing in eating disorders.
Science.gov (United States)
Serino, Silvia; Dakanalis, Antonios; Gaudio, Santino; Carrà, Giuseppe; Cipresso, Pietro; Clerici, Massimo; Riva, Giuseppe
2015-12-15
A distorted body representation is a core symptom in eating disorders (EDs), though its mechanism is unclear. Allocentric lock theory, emphasising the role of reference frame processing in body image, suggests that ED patients may be (b)locked to an (allocentric) representation of their own body stored in long-term memory (e.g., my body is fat) that is not updated (modified) by the (real-time egocentric) perception-driven experience of the physical body. Employing a well-validated virtual reality-based procedure, relative to healthy controls, ED patients showed deficits in the ability to refer to and update a long-term stored (allocentric) representation with (egocentric) perceptual-driven inputs. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
4. Future global SLR network evolution and its impact on the terrestrial reference frame
Science.gov (United States)
Kehm, Alexander; Bloßfeld, Mathis; Pavlis, Erricos C.; Seitz, Florian
2018-06-01
Satellite laser ranging (SLR) is an important technique that contributes to the determination of terrestrial geodetic reference frames, especially to the realization of the origin and the scale of global networks. One of the major limiting factors of SLR-derived reference frame realizations is the datum accuracy which significantly suffers from the current global SLR station distribution. In this paper, the impact of a potential future development of the SLR network on the estimated datum parameters is investigated. The current status of the SLR network is compared to a simulated potential future network featuring additional stations improving the global network geometry. In addition, possible technical advancements resulting in a higher amount of observations are taken into account as well. As a result, we find that the network improvement causes a decrease in the scatter of the network translation parameters of up to 24%, and up to 20% for the scale, whereas the technological improvement causes a reduction in the scatter of up to 27% for the translations and up to 49% for the scale. The Earth orientation parameters benefit by up to 15% from both effects.
5. Adaptive Interval Type-2 Fuzzy Logic Control for PMSM Drives with a Modified Reference Frame
KAUST Repository
Chaoui, Hicham
2017-01-10
In this paper, an adaptive interval type-2 fuzzy logic control scheme is proposed for high-performance permanent magnet synchronous machine drives. This strategy combines the power of type-2 fuzzy logic systems with the adaptive control theory to achieve accurate tracking and robustness to higher uncertainties. Unlike other controllers, the proposed strategy does not require electrical transducers and hence, no explicit currents loop regulation is needed, which yields a simplified control scheme. But, this limits the machine\\'s operation range since it results in a higher energy consumption. Therefore, a modified reference frame is also proposed in this paper to decrease the machine\\'s consumption. To better assess the performance of the new reference frame, comparison against its original counterpart is carried-out under the same conditions. Moreover, the stability of the closed-loop control scheme is guaranteed by a Lyapunov theorem. Simulation and experimental results for numerous situations highlight the effectiveness of the proposed controller in standstill, transient, and steady-state conditions.
6. Analysis, Design, and Experimental Verification of A Synchronous Reference Frame Voltage Control for Single-Phase Inverters
DEFF Research Database (Denmark)
Monfared, Mohammad; Golestan, Saeed; Guerrero, Josep M.
2014-01-01
Control of three-phase power converters in the synchronous reference frame is now a mature and well developed research topic. However, for single-phase converters, it is not as well-established as three-phase applications. This paper deals with the design of a synchronous reference frame multi-lo...... on a frequency response approach is presented. Finally, the theoretical achievements are supported by experimental results.......-loop control strategy for single phase inverter-based islanded distributed generation (DG) systems. The proposed controller uses a synchronous reference frame PI (SRFPI) controller to regulate the instantaneous output voltage, a capacitor current shaping loop in the stationary reference frame to provide active...
7. Locations of serial reach targets are coded in multiple reference frames.
Science.gov (United States)
Thompson, Aidan A; Henriques, Denise Y P
2010-12-01
Previous work from our lab, and elsewhere, has demonstrated that remembered target locations are stored and updated in an eye-fixed reference frame. That is, reach errors systematically vary as a function of gaze direction relative to a remembered target location, not only when the target is viewed in the periphery (Bock, 1986, known as the retinal magnification effect), but also when the target has been foveated, and the eyes subsequently move after the target has disappeared but prior to reaching (e.g., Henriques, Klier, Smith, Lowy, & Crawford, 1998; Sorrento & Henriques, 2008; Thompson & Henriques, 2008). These gaze-dependent errors, following intervening eye movements, cannot be explained by representations whose frame is fixed to the head, body or even the world. However, it is unknown whether targets presented sequentially would all be coded relative to gaze (i.e., egocentrically/absolutely), or if they would be coded relative to the previous target (i.e., allocentrically/relatively). It might be expected that the reaching movements to two targets separated by 5° would differ by that distance. But, if gaze were to shift between the first and second reaches, would the movement amplitude between the targets differ? If the target locations are coded allocentrically (i.e., the location of the second target coded relative to the first) then the movement amplitude should be about 5°. But, if the second target is coded egocentrically (i.e., relative to current gaze direction), then the reaches to this target and the distances between the subsequent movements should vary systematically with gaze as described above. We found that requiring an intervening saccade to the opposite side of 2 briefly presented targets between reaches to them resulted in a pattern of reaching error that systematically varied as a function of the distance between current gaze and target, and led to a systematic change in the distance between the sequential reach endpoints as predicted by
8. Parametrized post-Newtonian theory of reference frames, multipolar expansions and equations of motion in the N-body problem
International Nuclear Information System (INIS)
Kopeikin, Sergei; Vlasov, Igor
2004-01-01
Post-Newtonian relativistic theory of astronomical reference frames based on Einstein's general theory of relativity was adopted by General Assembly of the International Astronomical Union in 2000. This theory is extended in the present paper by taking into account all relativistic effects caused by the presumable existence of a scalar field and parametrized by two parameters, β and γ, of the parametrized post-Newtonian (PPN) formalism. We use a general class of the scalar-tensor (Brans-Dicke type) theories of gravitation to work out PPN concepts of global and local reference frames for an astronomical N-body system. The global reference frame is a standard PPN coordinate system. A local reference frame is constructed in the vicinity of a weakly self-gravitating body (a sub-system of the bodies) that is a member of the astronomical N-body system. Such local inertial frame is required for unambiguous derivation of the equations of motion of the body in the field of other members of the N-body system and for construction of adequate algorithms for data analysis of various gravitational experiments conducted in ground-based laboratories and/or on board of spacecrafts in the solar system.We assume that the bodies comprising the N-body system have weak gravitational field and move slowly. At the same time we do not impose any specific limitations on the distribution of density, velocity and the equation of state of the body's matter. Scalar-tensor equations of the gravitational field are solved by making use of the post-Newtonian approximations so that the metric tensor and the scalar field are obtained as functions of the global and local coordinates. A correspondence between the local and global coordinate frames is found by making use of asymptotic expansion matching technique. This technique allows us to find a class of the post-Newtonian coordinate transformations between the frames as well as equations of translational motion of the origin of the local frame
9. A Kalman filter approach for the determination of celestial reference frames
Science.gov (United States)
Soja, Benedikt; Gross, Richard; Jacobs, Christopher; Chin, Toshio; Karbon, Maria; Nilsson, Tobias; Heinkelmann, Robert; Schuh, Harald
2017-04-01
10. A Novel Real-Time Reference Key Frame Scan Matching Method
Directory of Open Access Journals (Sweden)
Haytham Mohamed
2017-05-01
Full Text Available Unmanned aerial vehicles represent an effective technology for indoor search and rescue operations. Typically, most indoor missions’ environments would be unknown, unstructured, and/or dynamic. Navigation of UAVs in such environments is addressed by simultaneous localization and mapping approach using either local or global approaches. Both approaches suffer from accumulated errors and high processing time due to the iterative nature of the scan matching method. Moreover, point-to-point scan matching is prone to outlier association processes. This paper proposes a low-cost novel method for 2D real-time scan matching based on a reference key frame (RKF. RKF is a hybrid scan matching technique comprised of feature-to-feature and point-to-point approaches. This algorithm aims at mitigating errors accumulation using the key frame technique, which is inspired from video streaming broadcast process. The algorithm depends on the iterative closest point algorithm during the lack of linear features which is typically exhibited in unstructured environments. The algorithm switches back to the RKF once linear features are detected. To validate and evaluate the algorithm, the mapping performance and time consumption are compared with various algorithms in static and dynamic environments. The performance of the algorithm exhibits promising navigational, mapping results and very short computational time, that indicates the potential use of the new algorithm with real-time systems.
11. Rigorous Combination of GNSS and VLBI: How it Improves Earth Orientation and Reference Frames
Science.gov (United States)
Lambert, S. B.; Richard, J. Y.; Bizouard, C.; Becker, O.
2017-12-01
Current reference series (C04) of the International Earth Rotation and Reference Systems Service (IERS) are produced by a weighted combination of Earth orientation parameters (EOP) time series built up by combination centers of each technique (VLBI, GNSS, Laser ranging, DORIS). In the future, we plan to derive EOP from a rigorous combination of the normal equation systems of the four techniques.We present here the results of a rigorous combination of VLBI and GNSS pre-reduced, constraint-free, normal equations with the DYNAMO geodetic analysis software package developed and maintained by the French GRGS (Groupe de Recherche en GeÌodeÌsie Spatiale). The used normal equations are those produced separately by the IVS and IGS combination centers to which we apply our own minimal constraints.We address the usefulness of such a method with respect to the classical, a posteriori, combination method, and we show whether EOP determinations are improved.Especially, we implement external validations of the EOP series based on comparison with geophysical excitation and examination of the covariance matrices. Finally, we address the potential of the technique for the next generation celestial reference frames, which are currently determined by VLBI only.
12. Impact of uncertain reference-frame motions in plate kinematic reconstructions
DEFF Research Database (Denmark)
Iaffaldano, Giampiero; Stein, Seth
2017-01-01
Geoscientists infer past plate motions, which serve as fundamental constraints for a range of studies, from observations of magnetic isochrons as well as hotspots tracks on the ocean floor and, for stages older than the Cretaceous, from paleomagnetic data. These observations effectively represent...... time-integrals of past plate motions but, because they are made at present, yield plate kinematics naturally tied to a present-day reference-frame, which may be another plate or a hotspots system. These kinematics are therefore different than those occurred at the time when the rocks acquired...... – in a temporal sense – and prone to noise. This limitation is commonly perceived to hamper the correction of plate kinematic reconstructions for RFAMs, but the extent to which this may be the case has not been explored. Here we assess the impact of uncertain RFAMs on kinematic reconstructions using synthetic...
13. An alternative frame of reference for rehabilitation: the helping process versus the medical model.
Science.gov (United States)
Anderson, T P
1975-03-01
In rehabilitation the frame of reference of the helping professions is significantly different from the standard medical model in the following areas: the dynamics of the relationship, basis for client's trust of the professional, activity versus passivity of both the client and the professional, and the approach to identification and solution of client problems. "The helping process" as practiced in the helping professions is not doing the task, but assisting the client to do it himself, for himself. In this process the needs, values and feelings of both the helper and the helpee must be recognized and dealt with. For the helping process to be successful, three basic conditions are required: development of mutual trust, joint exploration of the problem(s) and listening by both sides. Also involved in attaining success in the helping process is an awareness of not only the barriers in receiving help but also the difficulties in giving help.
14. Classical relativistic ideal gas in thermodynamic equilibrium in a uniformly accelerated reference frame
International Nuclear Information System (INIS)
Louis-Martinez, Domingo J
2011-01-01
A classical (non-quantum-mechanical) relativistic ideal gas in thermodynamic equilibrium in a uniformly accelerated frame of reference is studied using Gibbs's microcanonical and grand canonical formulations of statistical mechanics. Using these methods explicit expressions for the particle, energy and entropy density distributions are obtained, which are found to be in agreement with the well-known results of the relativistic formulation of Boltzmann's kinetic theory. Explicit expressions for the total entropy, total energy and rest mass of the gas are obtained. The position of the center of mass of the gas in equilibrium is found. The non-relativistic and ultrarelativistic approximations are also considered. The phase space volume of the system is calculated explicitly in the ultrarelativistic approximation.
15. Analysis and controller design for stand-alone VSIs in synchronous reference frame
DEFF Research Database (Denmark)
Ramezani, Malek; Li, Shuhui; Golestan, Saeed
2017-01-01
-by-step graphical analysis and design approach for a three-phase stand-alone VSI system in the dq reference frame, which provides a clear systematic decoupling process to design the inner- and outer-loop current and voltage controllers, respectively. The closed-loop d- and q-axis output impedances of the stand......-alone VSI system by considering the coupling effects between axes are also formulated, modelled, and evaluated. The study investigates how the decoupling and compensating terms added in the current and voltage controllers affect the dynamic performance and output dq impedances of the VSI system. Simulation...... and hardware results verify the effectiveness of the graphic design and analysis strategy....
16. Simulation and Hardware Implementation of Shunt Active Power Filter Based on Synchronous Reference Frame Theory
Directory of Open Access Journals (Sweden)
Karthikrjan Senthilnathan
2018-02-01
Full Text Available This paper describes about the Hybrid Shunt Active Power Filter (HSAPF for the elimination of the current harmonics in the line side of the three phase three wire systems. The Active Power Filter is based on the Voltage Source Converter (VSC topology. The control strategy for the converter is based on Synchronous Reference Frame (SRF theory. The compensation of harmonics is done by the APF which is connected in the shunt configuration to the system. The Shunt APF has the better compensation of current harmonics. The design and implementation of Shunt active power filter is done by MATLAB/Simulink. The real time implementation by using the ATMEGA 8 Microcontroller. The Simulation and Hardware results shows that the current harmonics are eliminated in the system
17. Moving loads on flexible structures presented in the floating frame of reference formulation
Energy Technology Data Exchange (ETDEWEB)
Hartweg, Stefan, E-mail: stefan.hartweg@web.de; Heckmann, Andreas, E-mail: andreas.heckmann@dlr.de [German Aerospace Center (DLR), Institute of System Dynamics and Control (Germany)
2016-06-15
The introduction of moving loads in the Floating Frame of Reference Formulation is presented. We derive the kinematics and governing equations of motion of a general flexible multibody system and their extension to moving loads. The equivalence of convective effects with Coriolis and centripetal forces is shown. These effects are measured numerically and their significance in moving loads traveling at high speed is confirmed. A method is presented to handle discontinuities when moving loads separate from the flexible structure. The method is extended from beam models to general flexible structures obtained by means of the Finite Element Method. An interpolation method for the deformation field of the modal representation of these bodies is introduced.The work is concluded by application of the method to modern mechanical problems in numerical simulations.
18. Numerical Analysis of a Rotating Detonation Engine in the Relative Reference Frame
Science.gov (United States)
Paxson, Daniel E.
2014-01-01
A two-dimensional, computational fluid dynamic (CFD) simulation of a semi-idealized rotating detonation engine (RDE) is described. The simulation operates in the detonation frame of reference and utilizes a relatively coarse grid such that only the essential primary flow field structure is captured. This construction yields rapidly converging, steady solutions. Results from the simulation are compared to those from a more complex and refined code, and found to be in reasonable agreement. The performance impacts of several RDE design parameters are then examined. Finally, for a particular RDE configuration, it is found that direct performance comparison can be made with a straight-tube pulse detonation engine (PDE). Results show that they are essentially equivalent.
19. The General Medical Council: frame of reference or arbiter of morals?
Science.gov (United States)
Hill, D
1977-01-01
Many members of the public think of the General Medical Council (GMC) as the body which tries doctors: the doctors' law courts, as it were. And, except in the more sober of newspapers and news reports, the 'offences ' which receive the most publicity are those concerning alleged improper relations between doctors and patients. Professor Sir Denis Hill, in the following paper, which he read in the spring of this year to the annual conference of the London Medical Group devoted to a discussion of human sexuality, chose to examine the whole function of the General Medical Council as a frame of moral reference for doctors. Judging allegations of professional misconduct by doctors is the function of the Council's Disciplinary Committee. Judging sexual misconduct forms only a small part of their work. The GMC's responsibility covers the whole notion of morals and morality as it concerns doctors in their professional work. Sir Denis Hill stresses the modern thinking that morality must be learned and that attitudes are always shifting as society alters its norms of what is moral conduct. That is not to say that all that was previously considered not to be moral has now become acceptable but rather that other concepts have entered the field of moral debate. Therefore the GMC must constantly review the frame of reference it offers to doctors and the public may be surprised to learn that that process is never static. Sir Denis Hill in this paper is speaking personally and not as a member of the General Medical Council or of any of that body's special committees. PMID:926129
20. Contribution of Multi-GNSS Constellation to SLR-Derived Terrestrial Reference Frame
Science.gov (United States)
Sośnica, K.; Bury, G.; Zajdel, R.
2018-03-01
All satellites of new Global Navigation Satellite Systems (GNSS) are equipped with laser retroreflectors dedicated to Satellite Laser Ranging (SLR). This paper demonstrates the contribution of SLR tracking of multi-GNSS constellations to the improved SLR-derived reference frame and scientific products. We show a solution strategy with estimating satellite orbits, SLR station coordinates, geocenter coordinates, and Earth rotation parameters using SLR observations to 2 Laser Geodynamics Satellites (LAGEOS) and 55 GNSS satellites: 1 GPS, 31 Globalnaya Navigatsionnaya Sputnikovaya Sistema, 18 Galileo, 3 BeiDou Inclined Geosynchronous Orbit, 1 BeiDou Medium Earth Orbit, and 1 Quasi-Zenith Satellite System satellite for the period 2014.0-2017.4. Due to a substantial number of GNSS observations, the number of weekly solutions for some SLR stations, for example, Arkhyz, Komsomolsk, Altay, and Brasilia, is larger up to 41% in the combined LAGEOS + GNSS solution when compared to the LAGEOS-only solution. The SLR observations to GNSS can transfer the orientation of the reference frame from GNSS to SLR solutions. As a result, the SLR-derived pole coordinates and length-of-day estimates become more consistent with GNSS microwave-based results. The root-mean-square errors of length-of-day are reduced from 122.5 μs/d to 43.0 μs/d, whereas mean offsets are reduced from -81.6 μs/d to 0.5 μs/d in LAGEOS only and in the combined LAGEOS + GNSS solutions, respectively.
1. Decomposition of Riesz frames and waveletsinto a finite union of linearly independent sets
DEFF Research Database (Denmark)
Christensen, Ole; Lindner, Alexander M
2002-01-01
We characterize Riesz frames and prove that every Riesz frame is the union of a finite number of Riesz sequences. Furthermore, it is shown that for piecewise continuous wavelets with compact support, the associated regular wavelet systems can be decomposed into a finite number of linearly indepen...
2. Independent Electricity Market Operator integration management participant technical reference manual
International Nuclear Information System (INIS)
1999-01-01
The document provides potential participants with the essential technical information to permit them to participate in the IMO-administered markets, and is not intended to be a complete technical reference manual for all issues within the realm of electricity production, distribution, or consumption. Written for the participants, it provides only that information which is relevant to the participant for interfacing with the IMO and participating in the market. Written as a generic guide, all the information contained within it may not be relevant to all the participants. The document's intent is to provide participants with a description of the various facilities and interfaces required by market participants to take part in the IMO-administered markets. The document supplements the market rules and provides installation, set-up, and configuration information for the various tools and facilities that will be required for market participation as a supplier, carrier/delivery (transmitter/distributor), generator, or consumer in the market. Aspects considered include: participant workstation specifications, dispatch workstation specification, message exchange, remote terminal unit specification, AGC operational RTU specification, real time network connection specification, telephone connection specification, revenue administration specification, funds administration specification, data catalogues, market information, power grid connection requirements, and appendices
3. Investigation on Reference Frames and Time Systems in Multi-GNSS
Directory of Open Access Journals (Sweden)
Luca Nicolini
2018-01-01
4. A Terrestrial Reference Frame realised on the observation level using a GPS-LEO satellite constellation
Science.gov (United States)
Koenig, Daniel
2018-02-01
Applying a one-step integrated process, i.e. by simultaneously processing all data and determining all satellite orbits involved, a Terrestrial Reference Frame (TRF) consisting of a geometric as well as a dynamic part has been determined at the observation level using the EPOS-OC software of Deutsches GeoForschungsZentrum. The satellite systems involved comprise the Global Positioning System (GPS) as well as the twin GRACE spacecrafts. Applying a novel approach, the inherent datum defect has been overcome empirically. In order not to rely on theoretical assumptions this is done by carrying out the TRF estimation based on simulated observations and using the associated satellite orbits as background truth. The datum defect is identified here as the total of all three translations as well as the rotation about the z-axis of the ground station network leading to a rank-deficient estimation problem. To rectify this singularity, datum constraints comprising no-net translation (NNT) conditions in x, y, and z as well as a no-net rotation (NNR) condition about the z-axis are imposed. Thus minimally constrained, the TRF solution covers a time span of roughly a year with daily resolution. For the geometric part the focus is put on Helmert transformations between the a priori and the estimated sets of ground station positions, and the dynamic part is represented by gravity field coefficients of degree one and two. The results of a reference solution reveal the TRF parameters to be estimated reliably with high precision. Moreover, carrying out a comparable two-step approach using the same data and models leads to parameters and observational residuals of worse quality. A validation w.r.t. external sources shows the dynamic origin to coincide at a level of 5 mm or better in x and y, and mostly better than 15 mm in z. Comparing the derived GPS orbits to IGS final orbits as well as analysing the SLR residuals for the GRACE satellites reveals an orbit quality on the few cm level
5. Grid Synchronization of Wind Turbine Converters under Transient Grid Faults using a Double Synchronous Reference Frame PLL
DEFF Research Database (Denmark)
Teodorescu, Remus; Blaabjerg, Frede; Rodriguez, P.
2008-01-01
This work employs the Double Synchronous Reference Frame PLL (DSRF-PLL) as an effective method for grid synchronization of WT's power converters in the presence of transient faults in the grid. The DSRF-PLL exploits a dual synchronous reference frame voltage characterization, adding a decoupling...... network to a standard SRF-PLL in order to effectively separate the positive- and negative-sequence voltage components in a fast and accurate way. Experimental evaluation of the proposed grid synchronization method and simulations regarding its application to ride through transient faults verify...
6. The right frame of reference makes it simple: an example of introductory mechanics supported by video analysis of motion
International Nuclear Information System (INIS)
Klein, P; Gröber, S; Kuhn, J; Fleischhauer, A; Müller, A
2015-01-01
The selection and application of coordinate systems is an important issue in physics. However, considering different frames of references in a given problem sometimes seems un-intuitive and is difficult for students. We present a concrete problem of projectile motion which vividly demonstrates the value of considering different frames of references. We use this example to explore the effectiveness of video-based motion analysis (VBMA) as an instructional technique at university level in enhancing students’ understanding of the abstract concept of coordinate systems. A pilot study with 47 undergraduate students indicates that VBMA instruction improves conceptual understanding of this issue. (paper)
7. The right frame of reference makes it simple: an example of introductory mechanics supported by video analysis of motion
Science.gov (United States)
Klein, P.; Gröber, S.; Kuhn, J.; Fleischhauer, A.; Müller, A.
2015-01-01
The selection and application of coordinate systems is an important issue in physics. However, considering different frames of references in a given problem sometimes seems un-intuitive and is difficult for students. We present a concrete problem of projectile motion which vividly demonstrates the value of considering different frames of references. We use this example to explore the effectiveness of video-based motion analysis (VBMA) as an instructional technique at university level in enhancing students’ understanding of the abstract concept of coordinate systems. A pilot study with 47 undergraduate students indicates that VBMA instruction improves conceptual understanding of this issue.
8. International Celestial Reference Frame (ICRF): mantenimiento y extensión
Science.gov (United States)
Ma, C.; Arias, E. F.; Eubanks, T.; Fey, A. L.; Gontier, A.-M.; Jacobs, C. S.; Sovers, O. J.; Archinal, B. A.; Charlot, P.
A partir de enero de 1998 el sistema de referencia celeste convencional está representado por el International Celestial Reference System (ICRS) y materializado a través de las coordenadas VLBI del conjunto de radiofuentes extragalácticas que conforman el International Celestial Reference Frame (ICRF). La primera realización del ICRF, fue elaborada en 1995 por un grupo de expertos designado por la IAU, la que encomendó al International Earth Rotation Service el mantenimiento del ICRS, del ICRF y del vínculo con marcos de referencia en otras frecuencias. Una primera extensión del ICRF se realizó entre abril y junio de 1999, con el objetivo primario de proveer posiciones de radiofuentes extragalácticas observadas a partir de julio de 1995 y de mejorar las posiciones de las fuentes candidatas" con la inclusión de observaciones adicionales. Objetivos secundarios fueron monitorear a las radiofuentes para verificar que siguen siendo adecuadas para realizar al ICRF y mejorar las técnicas de análisis de datos. Como resultado del nuevo análisis se obtuvo una solución a partir de la cual se construyó la primera extensión del ICRF, denominada ICRF - Ext.1. Ella representa al ICRS, sus fuentes de definición se mantienen con las mismas posiciones y errores que en la primera realización del ICRF; las demás radiofuentes tienen coordenadas mejor determinadas que en ICRF; el marco de referencia se densificó con el agregado de 59 nuevas radiofuentes.
9. Quantum back-action-evading measurement of motion in a negative mass reference frame
Science.gov (United States)
Møller, Christoffer B.; Thomas, Rodrigo A.; Vasilakis, Georgios; Zeuthen, Emil; Tsaturyan, Yeghishe; Balabas, Mikhail; Jensen, Kasper; Schliesser, Albert; Hammerer, Klemens; Polzik, Eugene S.
2017-07-01
Quantum mechanics dictates that a continuous measurement of the position of an object imposes a random quantum back-action (QBA) perturbation on its momentum. This randomness translates with time into position uncertainty, thus leading to the well known uncertainty on the measurement of motion. As a consequence of this randomness, and in accordance with the Heisenberg uncertainty principle, the QBA puts a limitation—the so-called standard quantum limit—on the precision of sensing of position, velocity and acceleration. Here we show that QBA on a macroscopic mechanical oscillator can be evaded if the measurement of motion is conducted in the reference frame of an atomic spin oscillator. The collective quantum measurement on this hybrid system of two distant and disparate oscillators is performed with light. The mechanical oscillator is a vibrational ‘drum’ mode of a millimetre-sized dielectric membrane, and the spin oscillator is an atomic ensemble in a magnetic field. The spin oriented along the field corresponds to an energetically inverted spin population and realizes a negative-effective-mass oscillator, while the opposite orientation corresponds to an oscillator with positive effective mass. The QBA is suppressed by -1.8 decibels in the negative-mass setting and enhanced by 2.4 decibels in the positive-mass case. This hybrid quantum system paves the way to entanglement generation and distant quantum communication between mechanical and spin systems and to sensing of force, motion and gravity beyond the standard quantum limit.
10. Quantum back-action-evading measurement of motion in a negative mass reference frame.
Science.gov (United States)
Møller, Christoffer B; Thomas, Rodrigo A; Vasilakis, Georgios; Zeuthen, Emil; Tsaturyan, Yeghishe; Balabas, Mikhail; Jensen, Kasper; Schliesser, Albert; Hammerer, Klemens; Polzik, Eugene S
2017-07-12
Quantum mechanics dictates that a continuous measurement of the position of an object imposes a random quantum back-action (QBA) perturbation on its momentum. This randomness translates with time into position uncertainty, thus leading to the well known uncertainty on the measurement of motion. As a consequence of this randomness, and in accordance with the Heisenberg uncertainty principle, the QBA puts a limitation-the so-called standard quantum limit-on the precision of sensing of position, velocity and acceleration. Here we show that QBA on a macroscopic mechanical oscillator can be evaded if the measurement of motion is conducted in the reference frame of an atomic spin oscillator. The collective quantum measurement on this hybrid system of two distant and disparate oscillators is performed with light. The mechanical oscillator is a vibrational 'drum' mode of a millimetre-sized dielectric membrane, and the spin oscillator is an atomic ensemble in a magnetic field. The spin oriented along the field corresponds to an energetically inverted spin population and realizes a negative-effective-mass oscillator, while the opposite orientation corresponds to an oscillator with positive effective mass. The QBA is suppressed by -1.8 decibels in the negative-mass setting and enhanced by 2.4 decibels in the positive-mass case. This hybrid quantum system paves the way to entanglement generation and distant quantum communication between mechanical and spin systems and to sensing of force, motion and gravity beyond the standard quantum limit.
11. A Global Terrestrial Reference Frame from simulated VLBI and SLR data in view of GGOS
Science.gov (United States)
Glaser, Susanne; König, Rolf; Ampatzidis, Dimitrios; Nilsson, Tobias; Heinkelmann, Robert; Flechtner, Frank; Schuh, Harald
2017-07-01
In this study, we assess the impact of two combination strategies, namely local ties (LT) and global ties (GT), on the datum realization of Global Terrestrial Reference Frames in view of the Global Geodetic Observing System requiring 1 mm-accuracy. Simulated Very Long Baseline Interferometry (VLBI) and Satellite Laser Ranging (SLR) data over a 7 year time span was used. The LT results show that the geodetic datum can be best transferred if the precision of the LT is at least 1 mm. Investigating different numbers of LT, the lack of co-located sites on the southern hemisphere is evidenced by differences of 9 mm in translation and rotation compared to the solution using all available LT. For the GT, the combination applying all Earth rotation parameters (ERP), such as pole coordinates and UT1-UTC, indicates that the rotation around the Z axis cannot be adequately transferred from VLBI to SLR within the combination. Applying exclusively the pole coordinates as GT, we show that the datum can be transferred with mm-accuracy within the combination. Furthermore, adding artificial stations in Tahiti and Nigeria to the current VLBI network results in an improvement in station positions by 13 and 12%, respectively, and in ERP by 17 and 11%, respectively. Extending to every day VLBI observations leads to 65% better ERP estimates compared to usual twice-weekly VLBI observations.
12. Harnessing Wind Power in Moving Reference Frames with Application to Vehicles
Science.gov (United States)
Goushcha, Oleg; Felicissimo, Robert; Danesh-Yazdi, Amir; Andreopoulos, Yiannis
2017-11-01
The extraction of wind power from unique configurations embedded in moving vehicles by using micro-turbine devices has been investigated. In such moving environments, the specific power of the air motion is much greater and less intermittent than in stationary wind turbines anchored to the ground in open atmospheric conditions. In a translational frame of reference, the rate of work done by the drag force acting on the wind harnessing device due the relative motion of air should be taken into account in the overall performance evaluation through an energy balance. A device with a venting tube has been tested that connects a high-pressure stagnating flow region in the front of the vehicle with a low-pressure region at its rear. Our analysis identified two key areas to focus on for potentially significant rewards: (1) Vehicles with high energy conversion efficiency which require a high mass flow rate through the venting duct, and (2) low efficiency vehicles with wakes, which will be globally affected by the introduction of the venting duct device in a manner that reduces their drag so that there is a net gain in power generation.
13. Performance Evaluation of UPQC under Nonlinear Unbalanced Load Conditions Using Synchronous Reference Frame Based Control
Science.gov (United States)
Kota, Venkata Reddy; Vinnakoti, Sudheer
2017-12-01
Today, maintaining Power Quality (PQ) is very important in the growing competent world. With new equipments and devices, new challenges are also being put before power system operators. Unified Power Quality Conditioner (UPQC) is proposed to mitigate many power quality problems and to improve the performance of the power system. In this paper, an UPQC with Fuzzy Logic controller for capacitor voltage balancing is proposed in Synchronous Reference Frame (SRF) based control with Modified Phased Locked Loop (MPLL). The proposed controller with SRF-MPLL based control is tested under non-linear and unbalanced load conditions. The system is developed in Matlab/Simulink and its performance is analyzed under various conditions like non-linear, unbalanced load and polluted supply voltage including voltage sag/swells. Active and reactive power flow in the system, power factor and %THD of voltages and currents before and after compensation are also analyzed in this work. Results prove the applicability of the proposed scheme for power quality improvement. It is observed that the fuzzy controller gives better performance than PI controller with faster capacitor voltage balancing and also improves the dynamic performance of the system.
14. Reference frames for spatial frequency in face representation differ in the temporal visual cortex and amygdala.
Science.gov (United States)
Inagaki, Mikio; Fujita, Ichiro
2011-07-13
Social communication in nonhuman primates and humans is strongly affected by facial information from other individuals. Many cortical and subcortical brain areas are known to be involved in processing facial information. However, how the neural representation of faces differs across different brain areas remains unclear. Here, we demonstrate that the reference frame for spatial frequency (SF) tuning of face-responsive neurons differs in the temporal visual cortex and amygdala in monkeys. Consistent with psychophysical properties for face recognition, temporal cortex neurons were tuned to image-based SFs (cycles/image) and showed viewing distance-invariant representation of face patterns. On the other hand, many amygdala neurons were influenced by retina-based SFs (cycles/degree), a characteristic that is useful for social distance computation. The two brain areas also differed in the luminance contrast sensitivity of face-responsive neurons; amygdala neurons sharply reduced their responses to low luminance contrast images, while temporal cortex neurons maintained the level of their responses. From these results, we conclude that different types of visual processing in the temporal visual cortex and the amygdala contribute to the construction of the neural representations of faces.
15. Applicability of the "Frame of Reference" approach for environmental monitoring of offshore renewable energy projects.
Science.gov (United States)
Garel, Erwan; Rey, Cibran Camba; Ferreira, Oscar; van Koningsveld, Mark
2014-08-01
This paper assesses the applicability of the Frame of Reference (FoR) approach for the environmental monitoring of large-scale offshore Marine Renewable Energy (MRE) projects. The focus is on projects harvesting energy from winds, waves and currents. Environmental concerns induced by MRE projects are reported based on a classification scheme identifying stressors, receptors, effects and impacts. Although the potential effects of stressors on most receptors are identified, there are large knowledge gaps regarding the corresponding (positive and negative) impacts. In that context, the development of offshore MRE requires the implementation of fit-for-purpose monitoring activities aimed at environmental protection and knowledge development. Taking European legislation as an example, it is suggested to adopt standardized monitoring protocols for the enhanced usage and utility of environmental indicators. Towards this objective, the use of the FoR approach is advocated since it provides guidance for the definition and use of coherent set of environmental state indicators. After a description of this framework, various examples of applications are provided considering a virtual MRE project located in European waters. Finally, some conclusions and recommendations are provided for the successful implementation of the FoR approach and for future studies. Copyright © 2014 Elsevier Ltd. All rights reserved.
16. Allocentrically implied target locations are updated in an eye-centred reference frame.
Science.gov (United States)
Thompson, Aidan A; Glover, Christopher V; Henriques, Denise Y P
2012-04-18
When reaching to remembered target locations following an intervening eye movement a systematic pattern of error is found indicating eye-centred updating of visuospatial memory. Here we investigated if implicit targets, defined only by allocentric visual cues, are also updated in an eye-centred reference frame as explicit targets are. Participants viewed vertical bars separated by varying distances, and horizontal lines of equivalently varying lengths, implying a "target" location at the midpoint of the stimulus. After determining the implied "target" location from only the allocentric stimuli provided, participants saccaded to an eccentric location, and reached to the remembered "target" location. Irrespective of the type of stimulus reaching errors to these implicit targets are gaze-dependent, and do not differ from those found when reaching to remembered explicit targets. Implicit target locations are coded and updated as a function of relative gaze direction with respect to those implied locations just as explicit targets are, even though no target is specifically represented. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
17. IAEA activities related to safety indicators, time frames and reference scenarios
International Nuclear Information System (INIS)
Batandjieva, B.; Hioki, K.; Metcalf, P.
2002-01-01
The fundamental principles for the safe management of radioactive waste have been agreed internationally and form the basis for the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management that entered into force in June 2001. Protection of human health and the environment and safety of facilities (including radioactive waste disposal facilities) are widely recognised principles to be followed and demonstrated in post-closure safety assessment of waste repositories. Dose and risk are at present internationally agreed safety criteria, used for judging the acceptability of such facilities. However, there have been a number of activities initiated and co-ordinated by the International Atomic Energy Agency (IAEA) which have provided an international forum for discussion and consensus building on the use safety indicators which are complementary to dose and risk. The Agency has been working on the definition of other safety indicators, such as flux, time, environmental concentration, etc.; the desired characteristics, and use of these indicators in different time frames. The IAEA has focused on safety indicators related to geological disposal, exploring their role in the development of a safety case, evaluating the advantages and disadvantages of using other safety indicators and how they complement the dose and risk indicators. The use of these indicators have been discussed also from regulatory perspective, mainly in terms of achieving reasonable assurance and confidence in safety assessments for waste repositories and decision making in the presence of uncertainty in the context of disposal of long-lived waste. Considerable effort has also been expended by the Agency on the development and application of principles for defining critical groups and biospheres for deep geological repositories. One of the important and successful IAEA programmes in this field is the Biosphere Modelling and Assessment (BIOMASS) project
18. A Giant with Feet of Clay : A First Law and Economics Analysis of the Draft Common Frame of Reference (DCFR)
NARCIS (Netherlands)
Chirico, F.; van Damme, E.E.C.; Larouche, P.
2010-01-01
This paper contains the conclusions from the work of the Economic Impact Group (EIG), a part of the CoPECL Network of Excellence funded by the EU to prepare a Draft Common Frame of Reference (DCFR). Part 1 revisits basic principles which are central to the work of the whole group. For one, contract
19. When Students Doubt Their Teachers' Diagnostic Competence: Moderation in the Internal/External Frame of Reference Model
Science.gov (United States)
Zimmermann, Friederike; Möller, Jens; Köller, Olaf
2018-01-01
The internal/external frame of reference model (I/E model) posits that individuals' achievement-related self-concepts are formed through social comparisons (e.g., self vs. peers) within academic domains and dimensional comparisons (e.g., math vs. verbal) between distinct domains. A large body of research has supported the theorized pattern of…
20. An improved synchronous reference frame phase-locked loop for stand-alone variable speed constant frequency power generation systems
DEFF Research Database (Denmark)
Liu, Yi; Xu, Wei; Ke, Longzhang
2017-01-01
The phase-locked loop (PLL) based on conventional synchronous reference frame, i.e. dqPLL, is usually employed in grid-connected variable speed constant frequency (VSCF) power generation systems (PGSs). However, the voltage amplitude drop of stand-alone PGSs is often greater than that of the grid...
1. Frame-of-Reference Training: Establishing Reliable Assessment of Teaching Effectiveness.
Science.gov (United States)
Newman, Lori R; Brodsky, Dara; Jones, Richard N; Schwartzstein, Richard M; Atkins, Katharyn Meredith; Roberts, David H
2016-01-01
Frame-of-reference (FOR) training has been used successfully to teach faculty how to produce accurate and reliable workplace-based ratings when assessing a performance. We engaged 21 Harvard Medical School faculty members in our pilot and implementation studies to determine the effectiveness of using FOR training to assess health professionals' teaching performances. All faculty were novices at rating their peers' teaching effectiveness. Before FOR training, we asked participants to evaluate a recorded lecture using a criterion-based peer assessment of medical lecturing instrument. At the start of training, we discussed the instrument and emphasized its precise behavioral standards. During training, participants practiced rating lectures and received immediate feedback on how well they categorized and scored performances as compared with expert-derived scores of the same lectures. At the conclusion of the training, we asked participants to rate a post-training recorded lecture to determine agreement with the experts' scores. Participants and experts had greater rating agreement for the post-training lecture compared with the pretraining lecture. Through this investigation, we determined that FOR training is a feasible method to teach faculty how to accurately and reliably assess medical lectures. Medical school instructors and continuing education presenters should have the opportunity to be observed and receive feedback from trained peer observers. Our results show that it is possible to use FOR rater training to teach peer observers how to accurately rate medical lectures. The process is time efficient and offers the prospect for assessment and feedback beyond traditional learner evaluation of instruction.
2. The evaluation of a frame-of-reference training programme for intern psychometrists
Directory of Open Access Journals (Sweden)
Gerdi Mulder
2013-07-01
Full Text Available Orientation: The use of assessment centres (ACs has drastically increased over the past decade. However, ACs are constantly confronted with the lack of construct validity. One aspect of ACs that could improve the construct validity significantly is that of assessor training. Unfortunately untrained or poorly trained assessors are often used in AC processes. Research purpose: The purpose of this research was to evaluate a frame-of-reference (FOR programme to train intern psychometrists as assessors at an assessment centre. Motivation of study: The role of an assessor is important in an AC; therefore it is vital for an assessor to be able to evaluate and observe candidates’ behaviour adequately. Commencing with this training in a graduate psychometrist programme gives the added benefit of sending skilled psychometrists to the workplace. Research design, approach and method: A quantitative research approach was implemented, utilising a randomised pre-test-post-test comparison group design. Industrial Psychology postgraduate students (N = 22 at a South African university were used and divided into an experimental group (n = 11 and control group (n = 11. Three typical AC simulations were utilised as pre- and post-tests, and the ratings obtained from both groups were statistically analysed to determine the effect of the FOR training programme. Main findings: The data indicated that there was a significant increase in the familiarity of the participants with the one-on-one simulation and the group discussion simulation. Practical/managerial implications: Training intern psychometrists in a FOR programme could assist organisations in the appointment of more competent assessors. Contribution/value-add: To design an assessor training programme using FOR training for intern psychometrists in the South African context, specifically by incorporating this programme into the training programme for Honours students at universities.
3. Viewer-centered and body-centered frames of reference in direct visuomotor transformations.
Science.gov (United States)
Carrozzo, M; McIntyre, J; Zago, M; Lacquaniti, F
1999-11-01
It has been hypothesized that the end-point position of reaching may be specified in an egocentric frame of reference. In most previous studies, however, reaching was toward a memorized target, rather than an actual target. Thus, the role played by sensorimotor transformation could not be disassociated from the role played by storage in short-term memory. In the present study the direct process of sensorimotor transformation was investigated in reaching toward continuously visible targets that need not be stored in memory. A virtual reality system was used to present visual targets in different three-dimensional (3D) locations in two different tasks, one with visual feedback of the hand and arm position (Seen Hand) and the other without such feedback (Unseen Hand). In the Seen Hand task, the axes of maximum variability and of maximum contraction converge toward the mid-point between the eyes. In the Unseen Hand task only the maximum contraction correlates with the sight-line and the axes of maximum variability are not viewer-centered but rotate anti-clockwise around the body and the effector arm during the move from the right to the left workspace. The bulk of findings from these and previous experiments support the hypothesis of a two-stage process, with a gradual transformation from viewer-centered to body-centered and arm-centered coordinates. Retinal, extra-retinal and arm-related signals appear to be progressively combined in superior and inferior parietal areas, giving rise to egocentric representations of the end-point position of reaching.
4. The ICRF-3: Status, Plans, and Multi-wavelength Progress on the next generation Celestial Reference Frame.
Science.gov (United States)
Jacobs, Christopher
2015-08-01
ICRF-3 seeks to improve upon the highly successful ICRF-2. Our goals are to improve the precision, spatial and frequency coverage relative to the ICRF-2 by 2018. This date is driven by the desire to create radio frames that are ready for comparison with the Gaia optical frame.Several specific actions are underway. A collaboration to improve at S/X-band precision of the Very Long Baseline Array (VLBA) Calibrator Survey's ~2200 sources, which are typically 5 times less precise than the rest of the ICRF-2, is bearing fruit and is projected to yield a factor of 3 improvement in precision. S/X-band southern hemisphere precision improvements are underway with observations using southern antennas such as the AuScope, Warkworth, and HartRAO, South Africa.We also seek to improve radio frequency coverage with X/Ka-band and K-band work. An X/Ka frame of 660 sources now has full sky coverage from the addition of a 2nd southern station in Argentina which is strengthening the southern hemisphere in general. The X/Ka-band frame's precision is now comparable to the ICRF-2 for the 530 sources in common. A K-band collaboration has formed with similar coverage and southern precision goals. By the time of this meeting, we expect K-band to complete full sky coverage with south polar cap observations and to improve spatial density north of -30 deg declination with VLBA observations.On the analysis front, special attention is being given to combination techniques both of Very Long Baseline Interferometry (VLBI) frames and of multiple data types. Consistency of the Celestial Reference Frame (CRF) with the Terrestrial Reference Frame (TRF) and Earth Oreintation Parameters (EOP) is another area of concern. Comparison of celestial frame solutions from various groups is underway in order to identify and correct systematic errors. We will discuss evidence emerging for 100 µas zonal errors in the ICRF2 in the declination range from 0 to -30 deg.Finally, work is underway to identify and
5. A radio/optical reference frame. 5: Additional source positions in the mid-latitude southern hemisphere
Science.gov (United States)
Russell, J. L.; Reynolds, J. E.; Jauncey, D. L.; de Vegt, C.; Zacharias, N.; Ma, C.; Fey, A. L.; Johnston, K. J.; Hindsley, R.; Hughes, J. A.; Malin, D. F.; White, G. L.; Kawaguchi, N.; Takahashi, Y.
1994-01-01
6. Are OPERA neutrinos faster than light because of non-inertial reference frames?
Science.gov (United States)
Germanà, C.
2012-02-01
Context. Recent results from the OPERA experiment reported a neutrino beam traveling faster than light. The challenging experiment measured the neutrino time of flight (TOF) over a baseline from the CERN to the Gran Sasso site, concluding that the neutrino beam arrives ~60 ns earlier than a light ray would do. Because the result, if confirmed, has an enormous impact on science, it might be worth double-checking the time definitions with respect to the non-inertial system in which the neutrino travel time was measured. An observer with a clock measuring the proper time τ free of non-inertial effects is the one located at the solar system barycenter (SSB). Aims: Potential problems in the OPERA data analysis connected with the definition of the reference frame and time synchronization are emphasized. We aim to investigate the synchronization of non-inertial clocks on Earth by relating this time to the proper time of an inertial observer at SSB. Methods: The Tempo2 software was used to time-stamp events observed on the geoid with respect to the SSB inertial observer time. Results: Neutrino results from OPERA might carry the fingerprint of non-inertial effects because they are timed by terrestrial clocks. The CERN-Gran Sasso clock synchronization is accomplished by applying corrections that depend on special and general relativistic time dilation effects at the clocks, depending on the position of the clocks in the solar system gravitational well. As a consequence, TOF distributions are centered on values shorter by tens of nanoseconds than expected, integrating over a period from April to December, longer if otherwise. It is worth remarking that the OPERA runs have always been carried out from April/May to November. Conclusions: If the analysis by Tempo2 holds for the OPERA experiment, the excellent measurement by the OPERA collaboration will turn into a proof of the general relativity theory in a weak field approximation. The analysis presented here is falsifiable
7. Face-infringement space: the frame of reference of the ventral intraparietal area.
Science.gov (United States)
McCollum, Gin; Klam, François; Graf, Werner
2012-07-01
Experimental studies have shown that responses of ventral intraparietal area (VIP) neurons specialize in head movements and the environment near the head. VIP neurons respond to visual, auditory, and tactile stimuli, smooth pursuit eye movements, and passive and active movements of the head. This study demonstrates mathematical structure on a higher organizational level created within VIP by the integration of a complete set of variables covering face-infringement. Rather than positing dynamics in an a priori defined coordinate system such as those of physical space, we assemble neuronal receptive fields to find out what space of variables VIP neurons together cover. Section 1 presents a view of neurons as multidimensional mathematical objects. Each VIP neuron occupies or is responsive to a region in a sensorimotor phase space, thus unifying variables relevant to the disparate sensory modalities and movements. Convergence on one neuron joins variables functionally, as space and time are joined in relativistic physics to form a unified spacetime. The space of position and motion together forms a neuronal phase space, bridging neurophysiology and the physics of face-infringement. After a brief review of the experimental literature, the neuronal phase space natural to VIP is sequentially characterized, based on experimental data. Responses of neurons indicate variables that may serve as axes of neural reference frames, and neuronal responses have been so used in this study. The space of sensory and movement variables covered by VIP receptive fields joins visual and auditory space to body-bound sensory modalities: somatosensation and the inertial senses. This joining of allocentric and egocentric modalities is in keeping with the known relationship of the parietal lobe to the sense of self in space and to hemineglect, in both humans and monkeys. Following this inductive step, variables are formalized in terms of the mathematics of graph theory to deduce which
8. Nursing home staff members' subjective frames of reference on residents' achievement of ego integrity: A Q-methodology study.
Science.gov (United States)
Lim, Sun-Young; Chang, Sung-Ok
2018-01-01
To discover the structure of the frames of reference for nursing home staff members' subjective judgment of residents' achievement of ego integrity. Q-methodology was applied. Twenty-eight staff members who were working in a nursing home sorted 34 Q-statements into the shape of a normal distribution. A centroid factor analysis and varimax rotation, using the PQ-method program, revealed four factors: identifying clues to residents' positive acceptance of their whole life span, identifying residents' ways of enjoying their current life, referencing residents' attitudes and competencies toward harmonious relationships, and identifying residents' integrated efforts to establish self-esteem. These subjective frames of reference need to be investigated in order to improve the relationships with nursing home residents and their quality of life. Consequently, the fundamental monitoring tools to help staff members make subjective judgments can be formed. © 2017 Japan Academy of Nursing Science.
9. Performance Improvement of a Prefiltered Synchronous-Reference-Frame PLL By Using a PID-Type Loop Filter
DEFF Research Database (Denmark)
Golestan, Saeed; Monfared, Mohammad; Frejeido, Francisco
2014-01-01
Control Parameters design of a three-phase synchronous reference frame phase locked loop (SRF-PLL) with a pre-filtering stage (acting as the sequence separator) is not a trivial task. The conventional way to deal with this problem is to neglect the interaction between the SRF-PLL and pre-filterin......Control Parameters design of a three-phase synchronous reference frame phase locked loop (SRF-PLL) with a pre-filtering stage (acting as the sequence separator) is not a trivial task. The conventional way to deal with this problem is to neglect the interaction between the SRF-PLL and pre......-integral-derivative controller as the loop filter (instead of the commonly adopted proportionalintegral controller) and arranging a pole-zero cancellation. The suggested method is simple and efficient, and is applicable to the joint operation of different sequence separation techniques and the SRF-PLL. The effectiveness...
10. Greenberger-Horne-Zeilinger-like proof of Bell's theorem involving observers who do not share a reference frame
International Nuclear Information System (INIS)
2003-01-01
Vaidman described how a team of three players, each of them isolated in a remote booth, could use a three-qubit Greenberger-Horne-Zeilinger state to always win a game which would be impossible to always win without quantum resources. However, Vaidman's method requires all three players to share a common reference frame; it does not work if the adversary is allowed to disorientate one player. Here we show how to always win the game, even if the players do not share any reference frame. The introduced method uses a 12-qubit state which is invariant under any transformation R a xR b xR c (where R a =U a xU a xU a xU a , where U j is a unitary operation on a single qubit) and requires only single-qubit measurements. A number of further applications of this 12-qubit state are described
11. Differential School Contextual Effects for Math and English: Integrating the Big-Fish-Little-Pond Effect and the Internal/External Frame of Reference
Science.gov (United States)
Parker, Philip D.; Marsh, Herbert W.; Ludtke, Oliver; Trautwein, Ulrich
2013-01-01
The internal/external frame of reference and the big-fish-little-pond effect are two major models of academic self-concept formation which have considerable theoretical and empirical support. Integrating the domain specific and compensatory processes of the internal/external frame of reference model with the big-fish-little-pond effect suggests a…
12. Roadmap to a mutually consistent set of offshore vertical reference frames
NARCIS (Netherlands)
Slobbe, D.C.
2013-01-01
This thesis presents a combined approach for the realization of the (quasi-)geoid as a height reference surface and the vertical reference surface at sea (chart datum). This approach, specifically designed for shallow seas and coastal waters, provides the relation between the two vertical reference
13. Post-Newtonian reference frames for advanced theory of the lunar motion and for a new generation of Lunar laser ranging
International Nuclear Information System (INIS)
Xie, Yi.; Kopeikin, S.
2010-01-01
We overview a set of post-Newtonian reference frames for a comprehensive study of the orbital dynamics and rotational motion of Moon and Earth by means of lunar laser ranging. We employ a scalar-tensor theory of gravity depending on two post-Newtonian parameters, and utilize the relativistic resolutions on reference frames adopted by the International Astronomical Union in 2000. We assume that the solar system is isolated and space-time is asymptotically flat at infinity. The primary reference frame covers the entire space-time, has its origin at the solar-system barycenter and spatial axes stretching up to infinity. The solar-system barycenter frame is not rotating with respect to a set of distant quasars that are forming the International Celestial Reference Frame. The secondary reference frame has its origin at the Earth-Moon barycenter. The Earth-Moon barycenter frame is locally-inertial and is not rotating dynamically in the sense that equation of motion of a test particle moving with respect to the Earth-Moon barycenter frame, does not contain the Coriolis and centripetal forces. Two other local frames-geocentric and seleno centric-have their origins at the center of mass of Earth and Moon respectively and do not rotate dynamically. Each local frame is subject to the geodetic precession both with respect to other local frames and with respect to the International Celestial Reference Frame because of their relative motion with respect to each other. Theoretical advantage of the dynamically non-rotating local frames is in a more simple mathematical description. Each local frame can be aligned with the axes of International Celestial Reference Frame after applying the matrix of the relativistic precession. The set of one global and three local frames is introduced in order to fully decouple the relative motion of Moon with respect to Earth from the orbital motion of the Earth-Moon barycenter as well as to connect the coordinate description of the lunar motion
14. Can space ties on board GNSS satellites replace terrestrial ties in the implementation of Terrestrial Reference Frames?
Science.gov (United States)
Bruni, Sara; Zerbini, Susanna; Altamimi, Zuheir; Rebischung, Paul; Errico, Maddalena; Santi, Efisio
2016-04-01
The realization of Terrestrial Reference Frames (TRFs) must be periodically updated in order to account for newly acquired observations and for upgrades in data analysis procedures and/or combination techniques. Any innovative computation strategy should ameliorate the definition of the frame physical parameters, upon which a number of scientific applications critically rely. On the basis of the requirements of scientific cutting edge studies, the geodetic community has estimated that the present day challenge in the determination of TRFs is to provide a frame that is accurate and long-term stable at the level of 1 mm and 0.1 mm/y respectively. This work aims at characterizing the frame realized by a combination of Satellite Laser Ranging (SLR) and Global Navigation Satellite Systems (GNSS) observations via their co-location on board GNSS spacecrafts. In particular, it is established how such a frame compares to the traditional ITRF computation and what is the impact on the realization of the frame origin and scale. Four years of data from a global network encompassing about one hundred GNSS stations and all SLR sites have been analyzed. In order to ensure the highest possible consistency, the raw data of both techniques are treated with the same analysis Software (Bernese GNSS Software 5.2) following IERS2010 Conventions. Both weekly and long term solutions are carried out exploiting either the Bernese or the Combination and Analysis of Terrestrial Reference Frames (CATREF) Software packages. We present the results of a combination study involving GNSS data and SLR observations to the two LAGEOS and to the GNSS satellites equipped with retroreflector arrays. The latter type of measurements is currently not included in the computation of the official ITRF solutions. The assessment of the benefit that they could provide to the definition of the origin and scale of the ITRF is however worth investigating, as such data provide the potential for linking the GNSS and
15. Anandan quantum phase for a neutral particle with Fermi-Walker reference frame in the cosmic string background
International Nuclear Information System (INIS)
2010-01-01
We study geometric quantum phases in the relativistic and non-relativistic quantum dynamics of a neutral particle with a permanent magnetic dipole moment interacting with two distinct field configurations in a cosmic string spacetime. We consider the local reference frames of the observers are transported via Fermi-Walker transport and study the influence of the non-inertial effects on the phase shift of the wave function of the neutral particle due to the choice of this local frame. We show that the wave function of the neutral particle acquires non-dispersive relativistic and non-relativistic quantum geometric phases due to the topology of the spacetime, the interaction between the magnetic dipole moment with external fields and the spin-rotation coupling. However, due to the Fermi-Walker reference frame, no phase shift associated to the Sagnac effect appears in the quantum dynamics of a neutral particle. We show that in the absence of topological defect, the contribution to the quantum phase due to the spin-rotation coupling is equivalent to the Mashhoon effect in non-relativistic dynamics. (orig.)
16. Residues in the alternative reading frame tumor suppressor that influence its stability and p53-independent activities
International Nuclear Information System (INIS)
Tommaso, Anne di; Hagen, Jussara; Tompkins, Van; Muniz, Viviane; Dudakovic, Amel; Kitzis, Alain; Ladeveze, Veronique; Quelle, Dawn E.
2009-01-01
The Alternative Reading Frame (ARF) protein suppresses tumorigenesis through p53-dependent and p53-independent pathways. Most of ARF's anti-proliferative activity is conferred by sequences in its first exon. Previous work showed specific amino acid changes occurred in that region during primate evolution, so we programmed those changes into human p14ARF to assay their functional impact. Two human p14ARF residues (Ala 14 and Thr 31 ) were found to destabilize the protein while two others (Val 24 and Ala 41 ) promoted more efficient p53 stabilization and activation. Despite those effects, all modified p14ARF forms displayed robust p53-dependent anti-proliferative activity demonstrating there are no significant biological differences in p53-mediated growth suppression associated with simian versus human p14ARF residues. In contrast, p53-independent p14ARF function was considerably altered by several residue changes. Val 24 was required for p53-independent growth suppression whereas multiple residues (Val 24 , Thr 31 , Ala 41 and His 60 ) enabled p14ARF to block or reverse the inherent chromosomal instability of p53-null MEFs. Together, these data pinpoint specific residues outside of established p14ARF functional domains that influence its expression and signaling activities. Most intriguingly, this work reveals a novel and direct role for p14ARF in the p53-independent maintenance of genomic stability.
17. An independent accurate reference method for the determination of chromium in biological materials
NARCIS (Netherlands)
Lagerwaard, A.; Woittiez, J.R.W.; de Goeij, J.J.M.
1994-01-01
A method for the determination of Cr in biological materials with high accuracy is reported for use as an independent reference method. It is based on radiochemical neutron activation analysis (RNAA) in combination with an individual yield determination based on the online yield principle. A
18. The assessment of the transformation of global tectonic plate models and the global terrestrial reference frames using the Velocity Decomposition Analysis
Science.gov (United States)
Ampatzidis, Dimitrios; König, Rolf; Glaser, Susanne; Heinkelmann, Robert; Schuh, Harald; Flechtner, Frank; Nilsson, Tobias
2016-04-01
The aim of our study is to assess the classical Helmert similarity transformation using the Velocity Decomposition Analysis (VEDA). The VEDA is a new methodology, developed by GFZ for the assessment of the reference frames' temporal variation and it is based on the separation of the velocities into two specified parts: The first is related to the reference system choice (the so called datum effect) and the latter one which refers to the real deformation of the terrestrial points. The advantage of the VEDA is its ability to detect the relative biases and reference system effects between two different frames or two different realizations of the same frame, respectively. We apply the VEDA for the assessment between several modern tectonic plate models and the recent global terrestrial reference frames.
19. A Stationary Reference Frame Grid Synchronization System for Three-Phase Grid-Connected Power Converters Under Adverse Grid Conditions
DEFF Research Database (Denmark)
Rodríguez, P.; Luna, A.; Muñoz-Aguilar, R. S.
2012-01-01
synchronization method for three-phase three-wire networks, namely dual second-order generalized integrator (SOGI) frequency-locked loop. The method is based on two adaptive filters, implemented by using a SOGI on the stationary αβ reference frame, and it is able to perform an excellent estimation......Grid synchronization algorithms are of great importance in the control of grid-connected power converters, as fast and accurate detection of the grid voltage parameters is crucial in order to implement stable control strategies under generic grid conditions. This paper presents a new grid...
20. Study and Analysis of a Natural Reference Frame Current Controller for a Multi-Level H-Bridge Power Converter
DEFF Research Database (Denmark)
Ciobotaru, Mihai; Iov, Florin; Zanchetta, P.
2008-01-01
will be needed in order to control the power flow and to ensure proper and secure operation of this future grid with an increased level of renewable power. These power converters must be able to provide intelligent power management as well as ancillary services. This paper presents an analysis of the natural...... reference frame controller, based on proportional-resonant (PR) technique, for a multi-level H-bridge power converter for Universal and Flexible Power Management in Future Electricity Network. The proposed method is tested in terms of harmonic content in the Point of Common Coupling (PCC), voltage...
1. Structured perceptual input imposes an egocentric frame of reference-pointing, imagery, and spatial self-consciousness.
Science.gov (United States)
Marcel, Anthony; Dobel, Christian
2005-01-01
Perceptual input imposes and maintains an egocentric frame of reference, which enables orientation. When blindfolded, people tended to mistake the assumed intrinsic axes of symmetry of their immediate environment (a room) for their own egocentric relation to features of the room. When asked to point to the door and window, known to be at mid-points of facing (or adjacent) walls, they pointed with their arms at 180 degrees (or 90 degrees) angles, irrespective of where they thought they were in the room. People did the same when requested to imagine the situation. They justified their responses (inappropriately) by logical necessity or a structural description of the room rather than (appropriately) by relative location of themselves and the reference points. In eight experiments, we explored the effect on this in perception and imagery of: perceptual input (without perceptibility of the target reference points); imaging oneself versus another person; aids to explicit spatial self-consciousness; order of questions about self-location; and the relation of targets to the axes of symmetry of the room. The results indicate that, if one is deprived of structured perceptual input, as well as losing one's bearings, (a) one is likely to lose one's egocentric frame of reference itself, and (b) instead of pointing to reference points, one demonstrates their structural relation by adopting the intrinsic axes of the environment as one's own. This is prevented by providing noninformative perceptual input or by inducing subjects to imagine themselves from the outside, which makes explicit the fact of their being located relative to the world. The role of perceptual contact with a structured world is discussed in relation to sensory deprivation and imagery, appeal is made to Gibson's theory of joint egoreception and exteroception, and the data are related to recent theories of spatial memory and navigation.
2. Separating electroweak and strong interactions in Drell-Yan processes at LHC: leptons angular distributions and reference frames
International Nuclear Information System (INIS)
Richter-Was, E.; Was, Z.
2016-01-01
Among the physics goals of LHC experiments, precision tests of the Standard Model in the Strong and Electroweak sectors play an important role. Because of nature of the proton-proton processes, observables based on the measurement of the direction and energy of leptons provide the most precise signatures. In the present paper, we concentrate on the angular distribution of Drell-Yan process leptons, in the lepton-pair rest-frame. The vector nature of the intermediate state imposes that distributions are to a good precision described by spherical polynomials of at most second order. We show that with the proper choice of the coordinate frames, only one coefficient in this polynomial decomposition remains sizable, even in the presence of one or two high p T jets. The necessary stochastic choice of the frames relies on probabilities independent from any coupling constants. This remains true when one or two partons accompany the lepton pairs. In this way electroweak effects can be better separated from strong interaction ones for the benefit of the interpretation of the measurements. Our study exploits properties of single gluon emission matrix elements which are clearly visible if a conveniently chosen form of their representation is used. We rely also on distributions obtained from matrix element based Monte Carlo generated samples of events with two leptons and up to two additional partons in test samples. Incoming colliding protons' partons are distributed accordingly to PDFs and are strictly collinear to the corresponding beams. (orig.)
3. Combined astrometric catalogue EOC-3 An improved reference frame for long-term Earth rotation studies
Czech Academy of Sciences Publication Activity Database
Vondrák, Jan; Štefka, Vojtěch
2007-01-01
Roč. 463, č. 2 (2007), s. 783-788 ISSN 0004-6361 R&D Projects: GA MŠk(CZ) LC506 Institutional research plan: CEZ:AV0Z10030501 Keywords : reference systems * astrometry * catalogs Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.259, year: 2007
4. Power quality improvement by unified power quality conditioner based on CSC topology using synchronous reference frame theory.
Science.gov (United States)
Dharmalingam, Rajasekaran; Dash, Subhransu Sekhar; Senthilnathan, Karthikrajan; Mayilvaganan, Arun Bhaskar; Chinnamuthu, Subramani
2014-01-01
This paper deals with the performance of unified power quality conditioner (UPQC) based on current source converter (CSC) topology. UPQC is used to mitigate the power quality problems like harmonics and sag. The shunt and series active filter performs the simultaneous elimination of current and voltage problems. The power fed is linked through common DC link and maintains constant real power exchange. The DC link is connected through the reactor. The real power supply is given by the photovoltaic system for the compensation of power quality problems. The reference current and voltage generation for shunt and series converter is based on phase locked loop and synchronous reference frame theory. The proposed UPQC-CSC design has superior performance for mitigating the power quality problems.
5. Power Quality Improvement by Unified Power Quality Conditioner Based on CSC Topology Using Synchronous Reference Frame Theory
Directory of Open Access Journals (Sweden)
Rajasekaran Dharmalingam
2014-01-01
Full Text Available This paper deals with the performance of unified power quality conditioner (UPQC based on current source converter (CSC topology. UPQC is used to mitigate the power quality problems like harmonics and sag. The shunt and series active filter performs the simultaneous elimination of current and voltage problems. The power fed is linked through common DC link and maintains constant real power exchange. The DC link is connected through the reactor. The real power supply is given by the photovoltaic system for the compensation of power quality problems. The reference current and voltage generation for shunt and series converter is based on phase locked loop and synchronous reference frame theory. The proposed UPQC-CSC design has superior performance for mitigating the power quality problems.
6. Power Quality Improvement by Unified Power Quality Conditioner Based on CSC Topology Using Synchronous Reference Frame Theory
Science.gov (United States)
Dharmalingam, Rajasekaran; Dash, Subhransu Sekhar; Senthilnathan, Karthikrajan; Mayilvaganan, Arun Bhaskar; Chinnamuthu, Subramani
2014-01-01
This paper deals with the performance of unified power quality conditioner (UPQC) based on current source converter (CSC) topology. UPQC is used to mitigate the power quality problems like harmonics and sag. The shunt and series active filter performs the simultaneous elimination of current and voltage problems. The power fed is linked through common DC link and maintains constant real power exchange. The DC link is connected through the reactor. The real power supply is given by the photovoltaic system for the compensation of power quality problems. The reference current and voltage generation for shunt and series converter is based on phase locked loop and synchronous reference frame theory. The proposed UPQC-CSC design has superior performance for mitigating the power quality problems. PMID:25013854
7. Variability of extragalactic sources: its contribution to the link between ICRF and the future Gaia Celestial Reference Frame
Science.gov (United States)
Taris, F.; Damljanovic, G.; Andrei, A.; Souchay, J.; Klotz, A.; Vachier, F.
2018-03-01
Context. The first release of the Gaia catalog is available since 14 September 2016. It is a first step in the realization of the future Gaia reference frame. This reference frame will be materialized by the optical positions of the sources and will be compared with and linked to the International Celestial Reference Frame, materialized by the radio position of extragalactic sources. Aim. As in the radio domain, it can be reasonably postulated that quasar optical flux variations can alert us to potential changes in the source structure. These changes could have important implications for the position of the target photocenters (together with the evolution in time of these centers) and in parallel have consequences for the link of the reference systems. Methods: A set of nine optical telescopes was used to monitor the magnitude variations, often at the same time as Gaia, thanks to the Gaia Observation Forecast Tool. The Allan variances, which are statistical tools widely used in the atomic time and frequency community, are introduced. Results: This work describes the magnitude variations of 47 targets that are suitable for the link between reference systems. We also report on some implications for the Gaia catalog. For 95% of the observed targets, new information about their variability is reported. In the case of some targets that are well observed by the TAROT telescopes, the Allan time variance shows that the longest averaging period of the magnitudes is in the range 20-70 d. The observation period by Gaia for a single target largely exceeds these values, which might be a problem when the magnitude variations exhibit flicker or random walk noises. Preliminary computations show that if the coordinates of the targets studied in this paper were affected by a white-phase noise with a formal uncertainty of about 1 mas (due to astrophysical processes that are put in evidence by the magnitude variations of the sources), it would affect the precision of the link at the
8. Post-Newtonian Reference Frames For Advanced Theory Of The Lunar Motion And For A New Generation Of Lunar Laser Ranging
International Nuclear Information System (INIS)
Xie, Y.; Kopeikon, S.
2010-01-01
We overview a set of post-Newtonian reference frames for a comprehensive study of the orbital dynamics and rotational motion of Moon and Earth by means of lunar laser ranging (LLR). We employ a scalar-tensor theory of gravity depending on two post-Newtonian parameters, and , and utilize the relativistic resolutions on reference frames adopted by the International Astronomical Union (IAU) in 2000. We assume that the solar system is isolated and space-time is asymptotically flat at infinity. The primary reference frame covers the entire space-time, has its origin at the solar-system barycenter (SSB) and spatial axes stretching up to infinity. The SSB frame is not rotating with respect to a set of distant quasars that are forming the International Celestial Reference Frame (ICRF). The secondary reference frame has its origin at the Earth-Moon barycenter (EMB). The EMB frame is locally-inertial and is not rotating dynamically in the sense that equation of motion of a test particle moving with respect to the EMB frame, does not contain the Coriolis and centripetal forces. Two other local frames geocentric (GRF) and selenocentric (SRF) have their origins at the center of mass of Earth and Moon respectively and do not rotate dynamically. Each local frame is subject to the geodetic precession both with respect to other local frames and with respect to the ICRF because of their relative motion with respect to each other. Theoretical advantage of the dynamically non-rotating local frames is in a more simple mathematical description. Each local frame can be aligned with the axes of ICRF after applying the matrix of the relativistic precession. The set of one global and three local frames is introduced in order to fully decouple the relative motion of Moon with respect to Earth from the orbital motion of the Earth-Moon barycenter as well as to connect the coordinate description of the lunar motion, an observer on Earth, and a retro-reflector on Moon to directly measurable
9. Pneumafil casing blower through moving reference frame (MRF) - A CFD simulation
Science.gov (United States)
Manivel, R.; Vijayanandh, R.; Babin, T.; Sriram, G.
2018-05-01
In this analysis work, the ring frame of Pneumafil casing blower of the textile mills with a power rating of 5 kW have been simulated using Computational Fluid Dynamics (CFD) code. The CFD analysis of the blower is carried out in Ansys Workbench 16.2 with Fluent using MRF solver settings. The simulation settings and boundary conditions are based on literature study and field data acquired. The main objective of this work is to reduce the energy consumption of the blower. The flow analysis indicated that the power consumption is influenced by the deflector plate orientation and deflector plate strip situated at the outlet casing of the blower. The energy losses occurred in the blower is due to the recirculation zones formed around the deflector plate strip. The deflector plate orientation is changed and optimized to reduce the energy consumption. The proposed optimized model is based on the simulation results which had relatively lesser power consumption than the existing and other cases. The energy losses in the Pneumafil casing blower are reduced through CFD analysis.
10. Time-Dependent Selection of an Optimal Set of Sources to Define a Stable Celestial Reference Frame
Science.gov (United States)
Le Bail, Karine; Gordon, David
2010-01-01
Temporal statistical position stability is required for VLBI sources to define a stable Celestial Reference Frame (CRF) and has been studied in many recent papers. This study analyzes the sources from the latest realization of the International Celestial Reference Frame (ICRF2) with the Allan variance, in addition to taking into account the apparent linear motions of the sources. Focusing on the 295 defining sources shows how they are a good compromise of different criteria, such as statistical stability and sky distribution, as well as having a sufficient number of sources, despite the fact that the most stable sources of the entire ICRF2 are mostly in the Northern Hemisphere. Nevertheless, the selection of a stable set is not unique: studying different solutions (GSF005a and AUG24 from GSFC and OPA from the Paris Observatory) over different time periods (1989.5 to 2009.5 and 1999.5 to 2009.5) leads to selections that can differ in up to 20% of the sources. Observing, recording, and network improvement are some of the causes, showing better stability for the CRF over the last decade than the last twenty years. But this may also be explained by the assumption of stationarity that is not necessarily right for some sources.
11. Regular Formal Evaluation Sessions are Effective as Frame-of-Reference Training for Faculty Evaluators of Clerkship Medical Students.
Science.gov (United States)
Hemmer, Paul A; Dadekian, Gregory A; Terndrup, Christopher; Pangaro, Louis N; Weisbrod, Allison B; Corriere, Mark D; Rodriguez, Rechell; Short, Patricia; Kelly, William F
2015-09-01
Face-to-face formal evaluation sessions between clerkship directors and faculty can facilitate the collection of trainee performance data and provide frame-of-reference training for faculty. We hypothesized that ambulatory faculty who attended evaluation sessions at least once in an academic year (attendees) would use the Reporter-Interpreter-Manager/Educator (RIME) terminology more appropriately than faculty who did not attend evaluation sessions (non-attendees). Investigators conducted a retrospective cohort study using the narrative assessments of ambulatory internal medicine clerkship students during the 2008-2009 academic year. The study included assessments of 49 clerkship medical students, which comprised 293 individual teacher narratives. Single-teacher written and transcribed verbal comments about student performance were masked and reviewed by a panel of experts who, by consensus, (1) determined whether RIME was used, (2) counted the number of RIME utterances, and (3) assigned a grade based on the comments. Analysis included descriptive statistics and Pearson correlation coefficients. The authors reviewed 293 individual teacher narratives regarding the performance of 49 students. Attendees explicitly used RIME more frequently than non-attendees (69.8 vs. 40.4 %; p sessions used RIME terminology more frequently and provided more accurate grade recommendations than teachers who did not attend. Formal evaluation sessions may provide frame-of-reference training for the RIME framework, a method that improves the validity and reliability of workplace assessment.
12. The Role of Spatial Memory and Frames of Reference in the Precision of Angular Path Integration
OpenAIRE
Arthur, Joeanna C.; Philbeck, John W.; Kleene, Nicholas J.; Chichka, David
2012-01-01
Angular path integration refers to the ability to maintain an estimate of self-location after a rotational displacement by integrating internally-generated (idiothetic) self-motion signals over time. Previous work has found that non-sensory inputs, namely spatial memory, can play a powerful role in angular path integration (Arthur et al., 2007, 2009). Here we investigated the conditions under which spatial memory facilitates angular path integration. We hypothesized that the benefit of spatia...
13. Dragging of inertial frames.
Science.gov (United States)
Ciufolini, Ignazio
2007-09-06
The origin of inertia has intrigued scientists and philosophers for centuries. Inertial frames of reference permeate our daily life. The inertial and centrifugal forces, such as the pull and push that we feel when our vehicle accelerates, brakes and turns, arise because of changes in velocity relative to uniformly moving inertial frames. A classical interpretation ascribed these forces to acceleration relative to some absolute frame independent of the cosmological matter, whereas an opposite view related them to acceleration relative to all the masses and 'fixed stars' in the Universe. An echo and partial realization of the latter idea can be found in Einstein's general theory of relativity, which predicts that a spinning mass will 'drag' inertial frames along with it. Here I review the recent measurements of frame dragging using satellites orbiting Earth.
14. The Large Quasar Reference Frame (LQRF). An Optical Representation of the ICRS
Science.gov (United States)
2009-10-01
faint regimes, both the 2MASS and the preliminary northernmost UCAC2 positions are shown of astrometry consistent with the UCAC2 main catalog, and the...is used. 2.7. 2MASS The Two Micron All-Sky Survey point source catalog (Cutri et al. 2003), hereafter 2MASS , derives from an uniform scan of the...17.1, H = 16.4, and K = 15.3. The 2MASS contains the position of 470 992 970 sources, but no proper motions. The astrometry is referred to the
15. Design and validation of an open-source library of dynamic reference frames for research and education in optical tracking.
Science.gov (United States)
Brown, Alisa; Uneri, Ali; Silva, Tharindu De; Manbachi, Amir; Siewerdsen, Jeffrey H
2018-04-01
Dynamic reference frames (DRFs) are a common component of modern surgical tracking systems; however, the limited number of commercially available DRFs poses a constraint in developing systems, especially for research and education. This work presents the design and validation of a large, open-source library of DRFs compatible with passive, single-face tracking systems, such as Polaris stereoscopic infrared trackers (NDI, Waterloo, Ontario). An algorithm was developed to create new DRF designs consistent with intra- and intertool design constraints and convert to computer-aided design (CAD) files suitable for three-dimensional printing. A library of 10 such groups, each with 6 to 10 DRFs, was produced and tracking performance was validated in comparison to a standard commercially available reference, including pivot calibration, fiducial registration error (FRE), and target registration error (TRE). Pivot tests showed calibration error [Formula: see text], indistinguishable from the reference. FRE was [Formula: see text], and TRE in a CT head phantom was [Formula: see text], both equivalent to the reference. The library of DRFs offers a useful resource for surgical navigation research and could be extended to other tracking systems and alternative design constraints.
16. Equipment-independent reference values for dopamine transporter imaging with 123I-FP-CIT
International Nuclear Information System (INIS)
Koch, W.; Hornung, J.; Poepperl, G.; Tatsch, K.; Hamann, C.
2007-01-01
Aim: Reliable reference values are helpful to interpret and compare the results of dopamine transporter imaging with SPECT. Since semi-quantitative reference values cannot be easily transferred between imaging equipments, this study aimed to establish equipment independent normal values for the true striatal binding of 123 I-FP-CIT. Patients, methods: Specific striatal FP-CIT binding of 6 healthy volunteers and 26 patients with essential tremor were used to generate a reference range by applying an equipment specific resolution dependent factor to compensate for recovery effects. This factor has been determined previously by a series of standardized phantom measurements of an anthropomorphic basal ganglia phantom. Herewith, the resulting DAT binding values represent the expected true specific binding in the striatum. Results: On average, true specific striatal binding was 5.83 ± 0.96 in healthy controls, 5.25 ± 0.67 in patients with essential tremor and 5.36 ± 0.75 in the entire study cohort. Conclusion: These preliminary results may serve as a basis for the generation of a generally accepted equipment independent reference range for dopamine transporter imaging with 123 I-FP-CIT. By a simple phantom measurement that can be accomplished within one day factors related to specific imaging equipment and processing can be corrected for, resulting in specific binding values which may enable a more standardized interpretation of dopamine transporter scans. (orig.)
17. Quantum frames
Science.gov (United States)
Brown, Matthew J.
2014-02-01
The framework of quantum frames can help unravel some of the interpretive difficulties i the foundation of quantum mechanics. In this paper, I begin by tracing the origins of this concept in Bohr's discussion of quantum theory and his theory of complementarity. Engaging with various interpreters and followers of Bohr, I argue that the correct account of quantum frames must be extended beyond literal space-time reference frames to frames defined by relations between a quantum system and the exosystem or external physical frame, of which measurement contexts are a particularly important example. This approach provides superior solutions to key EPR-type measurement and locality paradoxes.
18. Media Framing
DEFF Research Database (Denmark)
Pedersen, Rasmus T.
2017-01-01
The concept of media framing refers to the way in which the news media organize and provide meaning to a news story by emphasizing some parts of reality and disregarding other parts. These patterns of emphasis and exclusion in news coverage create frames that can have considerable effects on news...... consumers’ perceptions and attitudes regarding the given issue or event. This entry briefly elaborates on the concept of media framing, presents key types of media frames, and introduces the research on media framing effects....
19. Frame of reference of software architecture for web applications and mobile
Directory of Open Access Journals (Sweden)
Carlos Alberto Maliza Martinez
2016-08-01
Full Text Available Given the need to have a guide for the implementation of informatics applications, and thus achieve automate tasks improving response times of users, designed the framework of reference the architecture software for web and mobile applications with technology free software and open source. The technology to be used is the Object Oriented Programming (OOP with JAVA programming language, a client / server architecture and style of multitier architecture, which will allow us to create scalable, robust and stable systems, together of Java Platform Enterprise Edition (JEE that helps us to implement business applications thanks to the JPA and EJB APIs. By the server for handling transactions, security, scalability and concurrency we have Wildfly application server. And on the client side, for creating graphical interfaces we use the ExtJS and Sencha Touch Framework, which are lightweight, high-performance libraries based on HTML5, JavaScript and CSS3. The report generator is JasperReports, because it has the ability to deliver rich content display and printer. The database engine is MySQL, because its connectivity, speed, and security make it a very appropriate server for access from the web. Finally, as editor of web and mobile applications, we have the integrated development environment Eclipse IDE platform of open source. In this paper we make a critical analysis of such applications and formulate the Framework of Software Architecture for the development and implementation of Web and Mobile Applications, which were implemented in the ECU911 Babahoyo and at the Instituto Tecnologico Superior Babahoyo, proving through its application their effectiveness and efficiency in the implementation of integrated systems
20. The role of scene type and priming in the processing and selection of a spatial frame of reference
Directory of Open Access Journals (Sweden)
Katrin eJohannsen
2013-04-01
Full Text Available The selection and processing of a spatial frame of reference (FOR in interpreting verbal scene descriptions is of great interest to psycholinguistics. In this study, we focus on the choice between the relative and the intrinsic FOR, addressing two questions: a does the presence or absence of a background in the scene influence the selection of a FOR, and b what is the effect of a previously selected FOR on the subsequent processing of a different FOR. Our results show that if a scene includes a realistic background, this will make the selection of the relative FOR more likely. We attribute this effect to the facilitation of mental simulation, which enhances the relation between the viewer and the objects. With respect to the response accuracy, we found both a higher (due to FOR priming and a lower accuracy (due to different FOR, while for the response latencies, we only found a delay effect.
1. PHOTOMETRIC OBSERVATIONS OF SELECTED, OPTICALLY BRIGHT QUASARS FOR SPACE INTERFEROMETRY MISSION AND OTHER FUTURE CELESTIAL REFERENCE FRAMES
International Nuclear Information System (INIS)
Ojha, Roopesh; Zacharias, Norbert; Hennessy, Gregory S.; Gaume, Ralph A.; Johnston, Kenneth J.
2009-01-01
Photometric observations of 235 extragalactic objects that are potential targets for the Space Interferometry Mission (SIM) are presented. Mean B, V, R, I magnitudes at the 5% level are obtained at 1-4 epochs between 2005 and 2007 using the 1 m telescopes at Cerro Tololo Inter-American Observatory and the Naval Observatory Flagstaff Station. Of the 134 sources that have V magnitudes in the Veron and Veron-Cetty catalog, a difference of over 1.0 mag is found for the observed-catalog magnitudes for about 36% of the common sources, and 10 sources show over 3 mag difference. Our first set of observations presented here form the basis of a long-term photometric variability study of the selected reference frame sources to assist in mission target selection and to support QSO multicolor photometric variability studies in general.
2. A New Way of Controlling Parallel-Connected Inverters by Using Synchronous-Reference-Frame Virtual Impedance Loop
DEFF Research Database (Denmark)
Guan, Yajuan; Guerrero, Josep M.; Zhao, Xin
2016-01-01
A novel simple and effective autonomous current-sharing controller for parallel three-phase inverters is proposed in this paper. The proposed controller provides faster response and better accuracy in contrast to the conventional droop control, since this novel approach does not require any active...... or reactive power calculations. Instead, a synchronous-reference-frame (SRF) virtual impedance loop and an SRF-based phase-locked loop are used. Stationary analysis is provided in order to identify the inherent mechanism of the direct and quadrature output currents in relation to the voltage amplitude...... from a setup with three parallel 2.2 kW inverters verify the effectiveness of the proposed control strategy in different scenarios....
3. Improved fault ride through capability of DFIG based wind turbines using synchronous reference frame control based dynamic voltage restorer.
Science.gov (United States)
Rini Ann Jerin, A; Kaliannan, Palanisamy; Subramaniam, Umashankar
2017-09-01
Fault ride through (FRT) capability in wind turbines to maintain the grid stability during faults has become mandatory with the increasing grid penetration of wind energy. Doubly fed induction generator based wind turbine (DFIG-WT) is the most popularly utilized type of generator but highly susceptible to the voltage disturbances in grid. Dynamic voltage restorer (DVR) based external FRT capability improvement is considered. Since DVR is capable of providing fast voltage sag mitigation during faults and can maintain the nominal operating conditions for DFIG-WT. The effectiveness of the DVR using Synchronous reference frame (SRF) control is investigated for FRT capability in DFIG-WT during both balanced and unbalanced fault conditions. The operation of DVR is confirmed using time-domain simulation in MATLAB/Simulink using 1.5MW DFIG-WT. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.
4. Adjoint-Based Design of Rotors Using the Navier-Stokes Equations in a Noninertial Reference Frame
Science.gov (United States)
Nielsen, Eric J.; Lee-Rausch, Elizabeth M.; Jones, William T.
2010-01-01
Optimization of rotorcraft flowfields using an adjoint method generally requires a time-dependent implementation of the equations. The current study examines an intermediate approach in which a subset of rotor flowfields are cast as steady problems in a noninertial reference frame. This technique permits the use of an existing steady-state adjoint formulation with minor modifications to perform sensitivity analyses. The formulation is valid for isolated rigid rotors in hover or where the freestream velocity is aligned with the axis of rotation. Discrete consistency of the implementation is demonstrated by using comparisons with a complex-variable technique, and a number of single- and multipoint optimizations for the rotorcraft figure of merit function are shown for varying blade collective angles. Design trends are shown to remain consistent as the grid is refined.
5. Outputs of paired Gabor filters summed across the background frame of reference predict the direction of movement
Science.gov (United States)
Lawton, Teri B.
1989-01-01
A cortical neural network that computes the visibility of shifts in the direction of movement is proposed. The network computes: (1) the magnitude of the position difference between the test and background patterns, (2) localized contrast differences at different spatial scales analyzed by computing temporal gradients of the difference and sum of the outputs of paired even- and odd-symmetric bandpass filters convolved with the input pattern, and (3) using global processes that pool the output from paired even- and odd-symmetric simple and complex cells across the spatial extent of the background frame of reference the direction a test pattern moved relative to a textured background. Evidence that magnocellular pathways are used to discriminate the direction of movement is presented. Since magnocellular pathways are used to discriminate the direction of movement, this task is not affected by small pattern changes such as jitter, short presentations, blurring, and different background contrasts that result when the veiling illumination in a scene changes.
6. Time Biases in laser ranging measurements; impacts on geodetic products (Reference Frame and Orbitography)
Science.gov (United States)
Belli, A.; Exertier, P.; Lemoine, F. G.; Chinn, D. S.; Zelensky, N. P.
2017-12-01
The GGOS objectives are to maintain a geodetic network with an accuracy of 1 mm and a stability of 0.1 mm per year. For years, the laser ranging technique, which provide very accurate absolute distances to geodetic targets enable to determine the scale factor as well as coordinates of the geocenter. In order to achieve this goal, systematic errors appearing in the laser ranging measurements must be considered and solved. In addition to Range Bias (RB), which is the primary source of uncertainty of the technique, Time Bias (TB) has been recently detected by using the Time Transfer by Laser Link (T2L2) space instrument capability on-board the satellite Jason-2. Instead of determining TB through the precise orbit determination that is applied to commonly used geodetic targets like LAGEOS to estimate global geodetic products, we have developed, independently, a dedicated method to transfer time between remote satellite laser ranging stations. As a result, the evolving clock phase shift to UTC of around 30 stations has been determined under the form of time series of time bias per station from 2008 to 2016 with an accuracy of 3-4 ns. It demonstrated the difficulty, in terms of Time & Frequency used technologies, to locally maintain accuracy and long term stability at least in the range of 100 ns that is the current requirement for time measurements (UTC) for the laser ranging technique. Because some laser ranging stations oftently exceed this limit (from 100 ns to a few μs) we have been studying these effects first on the precision orbit determination itself, second on the station positioning. We discuss the impact of TB on LAGEOS and Jason-2 orbits, which appears to affect the along-track component essentially. We also investigate the role of TB in global geodetic parameters as the station coordinates. Finally, we propose to provide the community with time series of time bias of laser ranging stations, under the form of a data- handling-file in order to be included in
7. Independence and deterrence. Britain and atomic energy 1945-1952. References to official papers
International Nuclear Information System (INIS)
Gowing, M.
1979-01-01
This booklet contains a list of references which were not published in Independence and Deterrence because they related to papers still closed under the 1958 and 1967 Public Records Acts. Since 1974, some post-war records have been reviewed by departments and the UKAEA and have been transferred to the Public Record Office; the earliest are already open and more will, of course, be opened in January each year. This list, unfortunately, cannot distinguish between papers open in the Public Record Office and those still closed in departmental archives. Even if it could, the distinction would become progressively out-of-date. We have however given as much information as we can to assist searchers. (author)
8. Safety Management. An Introduction to a Frame of Reference Exemplified with Case Studies from Non-Nuclear Contexts
Energy Technology Data Exchange (ETDEWEB)
Svensson, Ola (Risk Analysis, Social and Decision Research Unit, Dept. of Psychology, Stockholm Univ., Stockholm (Sweden)); Salo, Ilkka (Dept. of Psychology, Lund Univ., Lund (Sweden))
2004-11-15
A systems perspective on safety management is introduced followed by two briefly presented case studies of safety management in non-nuclear contexts. The first study concerns a car manufacturer and the second study a road traffic tunnel system. The risks of a car accident in the first case study are evident. The great exposure generates many incidents and accidents. In the second study, the rather low traffic intensity through the tunnel produces few incidents and accidents and only a few fatal accidents over the years. Yet, the risk of the individual traveler is much greater in the tunnel than on the average road. The case studies are presented in a systems perspective with emphasis on information feedback about the risks of the systems. The first case study illustrates high quality safety management, while the second case study shows many weaknesses of the safety management in the tunnel system. Some differences in safety management between the case studies are noted. The last part of the study presents an organizational perspective on safety management and offers alternative theoretical perspectives on the concept of safety management. The report shows that further studies are needed both (1) to develop a frame of reference for describing safety management across industries and activities and (2) to collect data illustrating of good and poor safety management. Then, the results can be used to strengthen and/or improving safety management in the nuclear power industry and its regulators
9. Safety Management. An Introduction to a Frame of Reference Exemplified with Case Studies from Non-Nuclear Contexts
International Nuclear Information System (INIS)
Svensson, Ola; Salo, Ilkka
2004-11-01
A systems perspective on safety management is introduced followed by two briefly presented case studies of safety management in non-nuclear contexts. The first study concerns a car manufacturer and the second study a road traffic tunnel system. The risks of a car accident in the first case study are evident. The great exposure generates many incidents and accidents. In the second study, the rather low traffic intensity through the tunnel produces few incidents and accidents and only a few fatal accidents over the years. Yet, the risk of the individual traveler is much greater in the tunnel than on the average road. The case studies are presented in a systems perspective with emphasis on information feedback about the risks of the systems. The first case study illustrates high quality safety management, while the second case study shows many weaknesses of the safety management in the tunnel system. Some differences in safety management between the case studies are noted. The last part of the study presents an organizational perspective on safety management and offers alternative theoretical perspectives on the concept of safety management. The report shows that further studies are needed both (1) to develop a frame of reference for describing safety management across industries and activities and (2) to collect data illustrating of good and poor safety management. Then, the results can be used to strengthen and/or improving safety management in the nuclear power industry and its regulators
10. Modified Synchronous Reference Frame Based Shunt Active Power Filter with Fuzzy Logic Control Pulse Width Modulation Inverter
Directory of Open Access Journals (Sweden)
Suleiman Musa
2017-05-01
Full Text Available Harmonic distortion in power networks has greatly reduced power quality and this affects system stability. In order to mitigate this power quality issue, the shunt active power filter (SAPF has been widely applied and it is proven to be the best solution to current harmonics. This paper evaluates the performance of the modified synchronous reference frame extraction (MSRF algorithm with fuzzy logic controller (FLC based current control pulse width modulation (PWM inverter of three-phase three-wire SAPF to mitigate current harmonics. The proposed FLC is designed with a reduced amount of membership functions (MFs and rules, and thus significantly reduces the computational time and memory size. Modeling and simulations of SAPF are carried out using MATLAB/Simulink R2012a with the power system toolbox under steady-state condition, and this is followed with hardware implementation using a TMS320F28335 digital signal processor (DSP, Specrum Digital Inc., Stafford, TX, USA. The results obtained demonstrate a good and satisfactory response to mitigate the harmonics in the system. The total harmonic distortion (THD for the system has been reduced from 25.60% to 0.92% and 1.41% in the simulation study with and without FLC, respectively. Similarly for the experimental study, the SAPF can compensate for the three-phase load current by reducing THD to 5.07% and 7.4% with and without FLC, respectively.
11. Cognitive ability, academic achievement and academic self-concept: extending the internal/external frame of reference model.
Science.gov (United States)
Chen, Ssu-Kuang; Hwang, Fang-Ming; Yeh, Yu-Chen; Lin, Sunny S J
2012-06-01
12. Bound states for a neutral particle analogous to a quantum dot induced by the non-inertial effects of the Fermi-Walker reference frame
International Nuclear Information System (INIS)
Bakke, Knut
2010-01-01
We study the appearance of bound states analogous to a quantum dot, proposed by Tan and Inkson (1996) , in the non-relativistic quantum dynamics of a neutral particle with permanent magnetic dipole moment induced by the non-inertial effects of the Fermi-Walker reference frame.
13. Comprehensive synchronous reference frame discrete-time modelling of a grid-connected PV for fast DC-side voltage control
NARCIS (Netherlands)
Almeida, P.M.; Barbosa, P.G.; Duarte, J.L.; Ribeiro, P.F.
2017-01-01
This paper presents a novel comprehensive discrete-time model of a three-phase single stage grid-connected photovoltaic generation system. The detailed model is carried out on synchronous reference frame. It is shown that both converter's AC and DC-side discrete time model differs from the
14. Explaining Paradoxical Relations Between Academic Self-Concepts and Achievements: Cross-Cultural Generalizability of the Internal/External Frame of Reference Predictions Across 26 Countries
Science.gov (United States)
Marsh, Herbert W.; Hau, Kit-Tai
2004-01-01
The internal/external frame of reference (I/E) model explains a seemingly paradoxical pattern of relations between math and verbal self-concepts and corresponding measures of achievement, extends social comparison theory, and has important educational implications. In a cross-cultural study of nationally representative samples of 15-year-olds from…
15. The Internal/External Frame of Reference Model of Self-Concept and Achievement Relations: Age-Cohort and Cross-Cultural Differences
Science.gov (United States)
Marsh, Herbert W.; Abduljabbar, Adel Salah; Parker, Philip D.; Morin, Alexandre J. S.; Abdelfattah, Faisal; Nagengast, Benjamin; Möller, Jens; Abu-Hilal, Maher M.
2015-01-01
The internal/external frame of reference (I/E) model and dimensional comparison theory posit paradoxical relations between achievement (ACH) and self-concept (SC) in mathematics (M) and verbal (V) domains; ACH in each domain positively affects SC in the matching domain (e.g., MACH to MSC) but negatively in the nonmatching domain (e.g., MACH to…
16. The Effect of Motion Analysis Activities in a Video-Based Laboratory in Students' Understanding of Position, Velocity and Frames of Reference
Science.gov (United States)
Koleza, Eugenia; Pappas, John
2008-01-01
In this article, we present the results of a qualitative research project on the effect of motion analysis activities in a Video-Based Laboratory (VBL) on students' understanding of position, velocity and frames of reference. The participants in our research were 48 pre-service teachers enrolled in Education Departments with no previous strong…
17. The purpose and coherence of the rules on good faith acquisition and acquisitive prescription in the Draft Common Frame of Reference: a tale of two gatekeepers
NARCIS (Netherlands)
Salomons, A.
2013-01-01
The drafters of Book VIII of the Draft Common Frame of Reference (DCFR) have consistently tried to formulate rules on the related topics of acquisitive prescription and good faith acquisition to further the underlying policy goals: where ordinary transfer has failed, good faith acquisition should
18. Explaining as Mediated Action: An Analysis of Pre-Service Teachers' Account of Forces of Inertia in Non-Inertial Frames of Reference
Science.gov (United States)
de Pereira, Alexsandro Pereira; Lima Junior, Paulo; Rodrigues, Renato Felix
2016-01-01
Explaining is one of the most important everyday practices in science education. In this article, we examine how scientific explanations could serve as cultural tools for members of a group of pre-service physics teachers. Specifically, we aim at their use of explanations about forces of inertia in non-inertial frames of reference. A basic…
19. A stationary reference frame current control for a multi-level H-bridge power converter for universal and flexible power management in future electricity network
DEFF Research Database (Denmark)
Ciobotaru, Mihai; Iov, Florin; Zanchetta, Pericle
2008-01-01
converters for grid connection of renewable sources will be needed. These power converters must be able to provide intelligent power management as well as ancillary services. This paper assesses a control method based on the stationary reference frame with Proportional-Resonant current controllers...
20. Effects of achievement differences for internal/external frame of reference model investigations: A test of robustness of findings over diverse student samples.
Science.gov (United States)
Schmidt, Isabelle; Brunner, Martin; Preckel, Franzis
2017-11-12
Achievement in math and achievement in verbal school subjects are more strongly correlated than the respective academic self-concepts. The internal/external frame of reference model (I/E model; Marsh, 1986, Am. Educ. Res. J., 23, 129) explains this finding by social and dimensional comparison processes. We investigated a key assumption of the model that dimensional comparisons mainly depend on the difference in achievement between subjects. We compared correlations between subject-specific self-concepts of groups of elementary and secondary school students with or without achievement differences in the respective subjects. The main goals were (1) to show that effects of dimensional comparisons depend to a large degree on the existence of achievement differences between subjects, (2) to demonstrate the generalizability of findings over different grade levels and self-concept scales, and (3) to test a rarely used correlation comparison approach (CCA) for the investigation of I/E model assumptions. We analysed eight German elementary and secondary school student samples (grades 3-8) from three independent studies (Ns 326-878). Correlations between math and German self-concepts of students with identical grades in the respective subjects were compared with the correlation of self-concepts of students having different grades using Fisher's Z test for independent samples. In all samples, correlations between math self-concept and German self-concept were higher for students having identical grades than for students having different grades. Differences in median correlations had small effect sizes for elementary school students and moderate effect sizes for secondary school students. Findings generalized over grades and indicated a developmental aspect in self-concept formation. The CCA complements investigations within I/E-research. © 2017 The British Psychological Society.
1. Transforming in-situ observations of CME-driven shock accelerated protons into the shock's reference frame.
Directory of Open Access Journals (Sweden)
I. M. Robinson
2005-07-01
Full Text Available We examine the solar energetic particle event following solar activity from 14, 15 April 2001 which includes a "bump-on-the-tail" in the proton energy spectra at 0.99 AU from the Sun. We find this population was generated by a CME-driven shock which arrived at 0.99 AU around midnight 18 April. As such this population represents an excellent opportunity to study in isolation, the effects of proton acceleration by the shock. The peak energy of the bump-on-the-tail evolves to progressively lower energies as the shock approaches the observing spacecraft at the inner Lagrange point. Focusing on the evolution of this peak energy we demonstrate a technique which transforms these in-situ spectral observations into a frame of reference co-moving with the shock whilst making allowance for the effects of pitch angle scattering and focusing. The results of this transform suggest the bump-on-the-tail population was not driven by the 15 April activity but was generated or at least modulated by a CME-driven shock which left the Sun on 14 April. The existence of a bump-on-the-tail population is predicted by models in Rice et al. (2003 and Li et al. (2003 which we compare with observations and the results of our analysis in the context of both the 14 April and 15 April CMEs. We find an origin of the bump-on-the-tail at the 14 April CME-driven shock provides better agreement with these modelled predictions although some discrepancy exists as to the shock's ability to accelerate 100 MeV protons.
Keywords. Solar physics, astrophysics and astronomy (Energetic particles; Flares and mass ejections – Space plasma physics (Transport processes
2. Oscillatory activity reflects differential use of spatial reference frames by sighted and blind individuals in tactile attention.
Science.gov (United States)
Schubert, Jonathan T W; Buchholz, Verena N; Föcker, Julia; Engel, Andreas K; Röder, Brigitte; Heed, Tobias
2015-08-15
Touch can be localized either on the skin in anatomical coordinates, or, after integration with posture, in external space. Sighted individuals are thought to encode touch in both coordinate systems concurrently, whereas congenitally blind individuals exhibit a strong bias for using anatomical coordinates. We investigated the neural correlates of this differential dominance in the use of anatomical and external reference frames by assessing oscillatory brain activity during a tactile spatial attention task. The EEG was recorded while sighted and congenitally blind adults received tactile stimulation to uncrossed and crossed hands while detecting rare tactile targets at one cued hand only. In the sighted group, oscillatory alpha-band activity (8-12Hz) in the cue-target interval was reduced contralaterally and enhanced ipsilaterally with uncrossed hands. Hand crossing attenuated the degree of posterior parietal alpha-band lateralization, indicating that attention deployment was affected by external spatial coordinates. Beamforming suggested that this posture effect originated in the posterior parietal cortex. In contrast, cue-related lateralization of central alpha-band as well as of beta-band activity (16-24Hz) were unaffected by hand crossing, suggesting that these oscillations exclusively encode anatomical coordinates. In the blind group, central alpha-band activity was lateralized, but did not change across postures. The pattern of beta-band activity was indistinguishable between groups. Because the neural mechanisms for posterior alpha-band generation seem to be linked to developmental vision, we speculate that the lack of this neural mechanism in blind individuals is related to their preferred use of anatomical over external spatial codes in sensory processing. Copyright © 2015 Elsevier Inc. All rights reserved.
3. Reference genome-independent assessment of mutation density using restriction enzyme-phased sequencing
Directory of Open Access Journals (Sweden)
Monson-Miller Jennifer
2012-02-01
Full Text Available Abstract Background The availability of low cost sequencing has spurred its application to discovery and typing of variation, including variation induced by mutagenesis. Mutation discovery is challenging as it requires a substantial amount of sequencing and analysis to detect very rare changes and distinguish them from noise. Also challenging are the cases when the organism of interest has not been sequenced or is highly divergent from the reference. Results We describe the development of a simple method for reduced representation sequencing. Input DNA was digested with a single restriction enzyme and ligated to Y adapters modified to contain a sequence barcode and to provide a compatible overhang for ligation. We demonstrated the efficiency of this method at SNP discovery using rice and arabidopsis. To test its suitability for the discovery of very rare SNP, one control and three mutagenized rice individuals (1, 5 and 10 mM sodium azide were used to prepare genomic libraries for Illumina sequencers by ligating barcoded adapters to NlaIII restriction sites. For genome-dependent discovery 15-30 million of 80 base reads per individual were aligned to the reference sequence achieving individual sequencing coverage from 7 to 15×. We identified high-confidence base changes by comparing sequences across individuals and identified instances consistent with mutations, i.e. changes that were found in a single treated individual and were solely GC to AT transitions. For genome-independent discovery 70-mers were extracted from the sequence of the control individual and single-copy sequence was identified by comparing the 70-mers across samples to evaluate copy number and variation. This de novo "genome" was used to align the reads and identify mutations as above. Covering approximately 1/5 of the 380 Mb genome of rice we detected mutation densities ranging from 0.6 to 4 per Mb of diploid DNA depending on the mutagenic treatment. Conclusions The
4. BATING A REFERENCE INSTALLATION BASED ON CONTROLLED-POTENTIAL COULOMETRY METOD IN THE FRAME OF IMPROVING THE STATE PRIMARY STANDARD GET 176 AND ITS MEASUREMENT CAPABILITIES
Directory of Open Access Journals (Sweden)
V. M. Zyskin
2016-01-01
Full Text Available The results of developing of reference installation, based on a controlled-potential coulometry, in the frame of improving the State primary standard of the units of mass (molar fraction and mass (molar concentration of a component in the liquid and solid substances and materials GET 176 are presented. The physical principles of controlled-potential coulometry, content and metrological characteristics of the developed installation are considered. Measurement results of copper, iron and lead contents in the certified reference materials of metals' solutions and CRM of brass produced by BAM, Germany, obtained using reference installation are given.
5. Relations between Temperament and Metacognition and Frames of Reference in Behaviors in Public Situations in Early and Middle Adolescence: An Analysis of Age Stages
Directory of Open Access Journals (Sweden)
Nana Kanzaki
2018-02-01
Full Text Available We conducted a questionnaire survey using a cross-sectional sample of early and middle adolescents aged 10–15 (n = 351 in order to investigate relationships between temperament, metacognition, and frames of reference in behaviors in public situations. The sample was divided into two groups by age (ear group: 10–12; middle-adolescence group: 13–15 and were analyzed by Multiple Group Structural Equation Modeling. Explanatory variables were four components of temperament [effortful control (EfC, affiliativeness (Afil, surgency (Sur, and negative affect (NgA] and metacognition. Objective variables were three components of frames of reference in behaviors in public situations [egocentrism (Ego, neighborhood evaluation (Nei, and public values (Pub]. In both age groups, EfC had a negative effect on Ego, and Sur had a negative effect on Nei. However, only in the middle-adolescence group did Afil and NgA have significant effects on Pub. Meanwhile, metacognition in the ear group had a positive effect on Ego and Nei, but these relations disappeared in the middle-adolescence group, and only in the middle-adolescence group did metacognition have a positive effect on Pub. We discuss frames of reference in behaviors in public situations from the viewpoint of the development of social cognition in early and middle adolescence in relation to temperament and metacognition.
6. Reference values of maximum walking speed among independent community-dwelling Danish adults aged 60 to 79 years
DEFF Research Database (Denmark)
Tibaek, S; Holmestad-Bechmann, N; Pedersen, Trine B
2015-01-01
OBJECTIVES: To establish reference values for maximum walking speed over 10m for independent community-dwelling Danish adults, aged 60 to 79 years, and to evaluate the effects of gender and age. DESIGN: Cross-sectional study. SETTING: Danish companies and senior citizens clubs. PARTICIPANTS: Two ...
7. Role of independent director in corporate governance – Reference to India
Directory of Open Access Journals (Sweden)
Indrajit Dube
2013-01-01
Full Text Available A company is the common platform of various stakeholders, such as customers, employees, investors, shareholders etc.. It is an instrument that can attract huge capital for doing business. Every transaction in a company should be fair and transparent to its stakeholders. A company having good Corporate Governance and an effective Board of Directors attract investors and ensure investment. Independence of the Board is critical to ensure that the board fulfills its role objectively and holds the management accountable to the company. The practice across jurisdictions indicates that the presence of Independent Director is answer to that. The present write up delves into the current scenario in Indian Corporate Sector and examine the role of Independent Director in Corporate Governance, in particular.
8. Utilizing a reference material for assessing absolute tumor mechanical properties in modality independent elastography
Science.gov (United States)
Kim, Dong Kyu; Weis, Jared A.; Yankeelov, Thomas E.; Miga, Michael I.
2014-03-01
There is currently no reliable method for early characterization of breast cancer response to neoadjuvant chemotherapy (NAC) [1,2]. Given that disruption of normal structural architecture occurs in cancer-bearing tissue, we hypothesize that further structural changes occur in response to NAC. Consequently, we are investigating the use of modalityindependent elastography (MIE) [3-8] as a method for monitoring mechanical integrity to predict long term outcomes in NAC. Recently, we have utilized a Demons non-rigid image registration method that allows 3D elasticity reconstruction in abnormal tissue geometries, making it particularly amenable to the evaluation of breast cancer mechanical properties. While past work has reflected relative elasticity contrast ratios [3], this study improves upon that work by utilizing a known stiffness reference material within the reconstruction framework such that a stiffness map becomes an absolute measure. To test, a polyvinyl alcohol (PVA) cryogel phantom and a silicone rubber mock mouse tumor phantom were constructed with varying mechanical stiffness. Results showed that an absolute measure of stiffness could be obtained based on a reference value. This reference technique demonstrates the ability to generate accurate measurements of absolute stiffness to characterize response to NAC. These results support that `referenced MIE' has the potential to reliably differentiate absolute tumor stiffness with significant contrast from that of surrounding tissue. The use of referenced MIE to obtain absolute quantification of biomarkers is also translatable across length scales such that the characterization method is mechanics-consistent at the small animal and human application.
9. Automatic Enhancement of the Reference Set for Multi-Criteria Sorting in The Frame of Theseus Method
Directory of Open Access Journals (Sweden)
Fernandez Eduardo
2014-05-01
Full Text Available Some recent works have established the importance of handling abundant reference information in multi-criteria sorting problems. More valid information allows a better characterization of the agent’s assignment policy, which can lead to an improved decision support. However, sometimes information for enhancing the reference set may be not available, or may be too expensive. This paper explores an automatic mode of enhancing the reference set in the framework of the THESEUS multi-criteria sorting method. Some performance measures are defined in order to test results of the enhancement. Several theoretical arguments and practical experiments are provided here, supporting a basic advantage of the automatic enhancement: a reduction of the vagueness measure that improves the THESEUS accuracy, without additional efforts from the decision agent. The experiments suggest that the errors coming from inadequate automatic assignments can be kept at a manageable level.
10. Framing the frame
OpenAIRE
Todd McElroy; John J. Seta
2007-01-01
We examined how the goal of a decision task influences the perceived positive, negative valence of the alternatives and thereby the likelihood and direction of framing effects. In Study 1 we manipulated the goal to increase, decrease or maintain the commodity in question and found that when the goal of the task was to increase the commodity, a framing effect consistent with those typically observed in the literature was found. When the goal was to decrease, a framing effect opposite to the ty...
11. Gravity in Gravity’s Rainbow – Force, Fictitious Force, and Frame of Reference; or: The Science and Poetry of Sloth
Directory of Open Access Journals (Sweden)
Nina Engelhardt
2014-09-01
Full Text Available Gravity is a prominent physical concept in 'Gravity's Rainbow', as already announced by the novel's title. If the second part of the title – the poetic image of the rainbow – is bound up with mathematical formulas and the parabolic path of the Rocket, so conversely, this paper argues, Pynchon's novel introduces a relation between gravity and fiction. The paper explores 'Gravity's Rainbow''s use of the changing historical understandings of gravitation from the seventeenth to the twentieth centuries by examining the novel's illustration of Newton and Leibniz's opposed concepts as well as its references to gravity as understood in Einstein's theory of relativity. When tracing the notions of gravity as force, fictitious force, and frame of reference, a particular focus lies on the relation of physical imagery to ethical questions and on the way 'Gravity's Rainbow' provides a physico-ethical explanation of Slothrop's disappearance from the novel.
12. Cost update: Technology, safety, and costs of decommissioning reference independent spent fuel storage installations
International Nuclear Information System (INIS)
Miles, T.L.
1994-07-01
The cost estimates originally developed in NUREG/CR-2210 for decommissioning five conceptual Independent Spent Fuel Storage Installations (ISFSIs) and their supporting ancillaries (hot cell and transporter) are updated from 1981 to 1993 dollars. The costs for labor and materials increased approximately at the rate of inflation, the cost of energy increased more slowly than the rate of inflation, and the cost of low-level radioactive waste disposal increased much more rapidly than the rate of inflation. A methodology and a formula are presented for estimating the cost of decommissioning the ISFSIs at some future time, based on these current cost estimates. The formula contains essentially the same elements as the formula given in 10 CFR 50.75 for escalating the decommissioning costs for nuclear power reactors to some future time
13. Temperature- and supply voltage-independent time references for wireless sensor networks
CERN Document Server
De Smedt, Valentijn; Dehaene, Wim
2015-01-01
This book investigates the possible circuit solutions to overcome the temperature- and supply voltage-sensitivity of fully-integrated time references for ultra-low-power communication in wireless sensor networks. The authors provide an elaborate theoretical introduction and literature study to enable full understanding of the design challenges and shortcomings of current oscillator implementations. Furthermore, a closer look to the short-term as well as the long-term frequency stability of integrated oscillators is taken. Next, a design strategy is developed and applied to 5 different oscillator topologies and 1 sensor interface.All 6 implementations are subject to an elaborate study of frequency stability, phase noise, and power consumption. In the final chapter all blocks are compared to the state of the art. The main goals of this book are: • to provide a comprehensive overview of timing issues and solutions in wireless sensor networks; • to gain understanding of all underlying mechanisms by starti...
14. A new velocity field for Africa from combined GPS and DORIS space geodetic Solutions: Contribution to the definition of the African reference frame (AFREF)
Science.gov (United States)
Saria, E.; Calais, E.; Altamimi, Z.; Willis, P.; Farah, H.
2013-04-01
We analyzed 16 years of GPS and 17 years of Doppler orbitography and radiopositioning integrated by satellite (DORIS) data at continuously operating geodetic sites in Africa and surroundings to describe the present-day kinematics of the Nubian and Somalian plates and constrain relative motions across the East African Rift. The resulting velocity field describes horizontal and vertical motion at 133 GPS sites and 9 DORIS sites. Horizontal velocities at sites located on stable Nubia fit a single plate model with a weighted root mean square residual of 0.6 mm/yr (maximum residual 1 mm/yr), an upper bound for plate-wide motions and for regional-scale deformation in the seismically active southern Africa and Cameroon volcanic line. We confirm significant southward motion ( ˜ 1.5 mm/yr) in Morocco with respect to Nubia, consistent with earlier findings. We propose an updated angular velocity for the divergence between Nubia and Somalia, which provides the kinematic boundary conditions to rifting in East Africa. We update a plate motion model for the East African Rift and revise the counterclockwise rotation of the Victoria plate and clockwise rotation of the Rovuma plate with respect to Nubia. Vertical velocities range from - 2 to +2 mm/yr, close to their uncertainties, with no clear geographic pattern. This study provides the first continent-wide position/velocity solution for Africa, expressed in International Terrestrial Reference Frame (ITRF2008), a contribution to the upcoming African Reference Frame (AFREF). Except for a few regions, the African continent remains largely under-sampled by continuous space geodetic data. Efforts are needed to augment the geodetic infrastructure and openly share existing data sets so that the objectives of AFREF can be fully reached.
15. Framing the frame
Directory of Open Access Journals (Sweden)
Todd McElroy
2007-08-01
Full Text Available We examined how the goal of a decision task influences the perceived positive, negative valence of the alternatives and thereby the likelihood and direction of framing effects. In Study 1 we manipulated the goal to increase, decrease or maintain the commodity in question and found that when the goal of the task was to increase the commodity, a framing effect consistent with those typically observed in the literature was found. When the goal was to decrease, a framing effect opposite to the typical findings was observed whereas when the goal was to maintain, no framing effect was found. When we examined the decisions of the entire population, we did not observe a framing effect. In Study 2, we provided participants with a similar decision task except in this situation the goal was ambiguous, allowing us to observe participants' self-imposed goals and how they influenced choice preferences. The findings from Study 2 demonstrated individual variability in imposed goal and provided a conceptual replication of Study 1. %need keywords
16. A two-level approach to VLBI terrestrial and celestial reference frames using both least-squares adjustment and Kalman filter algorithms
Science.gov (United States)
Soja, B.; Krasna, H.; Boehm, J.; Gross, R. S.; Abbondanza, C.; Chin, T. M.; Heflin, M. B.; Parker, J. W.; Wu, X.
2017-12-01
The most recent realizations of the ITRS include several innovations, two of which are especially relevant to this study. On the one hand, the IERS ITRS combination center at DGFI-TUM introduced a two-level approach with DTRF2014, consisting of a classical deterministic frame based on normal equations and an optional coordinate time series of non-tidal displacements calculated from geophysical loading models. On the other hand, the JTRF2014 by the combination center at JPL is a time series representation of the ITRF determined by Kalman filtering. Both the JTRF2014 and the second level of the DTRF2014 are thus able to take into account short-term variations in the station coordinates. In this study, based on VLBI data, we combine these two approaches, applying them to the determination of both terrestrial and celestial reference frames. Our product has two levels like DTRF2014, with the second level being a Kalman filter solution like JTRF2014. First, we compute a classical TRF and CRF in a global least-squares adjustment by stacking normal equations from 5446 VLBI sessions between 1979 and 2016 using the Vienna VLBI and Satellite Software VieVS (solution level 1). Next, we obtain coordinate residuals from the global adjustment by applying the level-1 TRF and CRF in the single-session analysis and estimating coordinate offsets. These residuals are fed into a Kalman filter and smoother, taking into account the stochastic properties of the individual stations and radio sources. The resulting coordinate time series (solution level 2) serve as an additional layer representing irregular variations not considered in the first level of our approach. Both levels of our solution are implemented in VieVS in order to test their individual and combined performance regarding the repeatabilities of estimated baseline lengths, EOP, and radio source coordinates.
17. Frame of Reference: Special Collections
Science.gov (United States)
Goetsch, Lori A.
2010-01-01
Rare, distinctive, unique--academic libraries are exploring new ways to describe and define what they've traditionally called special collections: incunabula, manuscripts, rare books, cultural artifacts and more. These valuable, historically important, and often one-of-a-kind artifacts can be a treasure trove for scholars and students. Technology…
18. Compliance Framing - Framing Compliance
OpenAIRE
Lutz-Ulrich Haack; Martin C. Reimann
2012-01-01
Corporations have to install various organizational measures to comply with legal as well as internal guidelines systematically. Compliance management systems have the challenging task to make use of an internal compliance-marketing approach in order to ensure not only an adequate but also effective compliance-culture. Compliance-literature and findings of persuasive goal-framing-theory give opposite implications for establishing a rather values- versus rule-based compliance-culture respectiv...
19. On Safety Management. A Frame of Reference for Studies of Safety Management with Examples From Non-Nuclear Contexts of Relevance for Nuclear Safety
International Nuclear Information System (INIS)
Svensson, Ola; Salo, Ilkka; Allwin, Pernilla
2004-11-01
operations, and safety management for each organization respectively. The analyses are described and summarized in detail in each chapter. To summarize some general themes from the analyzes the following are important to mention: -A distinct division of responsibilities for safety work between organizational units. -A clear communication about the organization's safety policy and how each member of the organization is a part of the policy. -Channels for information and information feedback are clearly represented in the system structure. -Availability to incident reporting systems and the responsibility of each member of the organization to report incidents. -The importance to differentiate between established structures for information management and established structures for information content. -To make clear the range and meaning of power and authority. -Identification of the organizations' competence and integrity in relation to safety management. -The importance of identifying threats to safety, not only for company activities and operations but also for authority activities and operations. In the next phase of the ongoing project, we wish to gain more insight in the companies' perspectives of safety management. The system theoretical framework outlined in this report will be used as a frame of reference for the analyses. We believe that the results from this and future studies in the project will give opportunities to take further steps towards improving safety in the nuclear power operations, both from a company and from a regulator perspective
20. Accuracy and Coordination of Spatial Frames of Reference during the Exploration of Virtual Maps: Interest for Orientation and Mobility of Blind People?
Directory of Open Access Journals (Sweden)
Mathieu Simonnet
2012-01-01
Full Text Available Even if their spatial reasoning capabilities remain quite similar to those of sighted people, blind people encounter difficulties in getting distant information from their surroundings. Thus, whole body displacements, tactile map consultations, or auditory solutions are needed to establish physical contacts with their environment. Therefore, the accuracy of nonvisual spatial representations heavily relies upon the efficiency of exploration strategies and the ability to coordinate egocentric and allocentric spatial frames of reference. This study aims to better understand the mechanisms of this coordination without vision by analyzing cartographic exploration strategies and assessing their influence on mental spatial representations. Six blind sailors were immersed within a virtual haptic and auditory maritime environment. They were required to learn the layout of the map. Their movements were recorded and we identified some exploration strategies. Then they had to estimate the directions of six particular seamarks in aligned and misaligned situations. Better accuracy and coordination were obtained when participants used the “central point of reference” strategy. Our discussion relative to the articulation between geometric enduring representations and salient transient perceptions provides implications on map reading techniques and on mobility and orientation programs for blind people.
1. An improved synchronous reference frame current control strategy for a photovoltaic grid-connected inverter under unbalanced and nonlinear load conditions
Science.gov (United States)
Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz; Miveh, Mohammad Reza; Guerrero, Josep M.
2017-01-01
In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions. It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed to control the active and reactive power and harmonic current compensation, and it also corrects the system unbalance. The proposed control method features the synchronous reference frame (SRF) method. Simulation results are presented to demonstrate the effective performance of the proposed method. PMID:28192436
2. An improved synchronous reference frame current control strategy for a photovoltaic grid-connected inverter under unbalanced and nonlinear load conditions.
Science.gov (United States)
Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz; Miveh, Mohammad Reza; Guerrero, Josep M
2017-01-01
In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions. It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed to control the active and reactive power and harmonic current compensation, and it also corrects the system unbalance. The proposed control method features the synchronous reference frame (SRF) method. Simulation results are presented to demonstrate the effective performance of the proposed method.
3. Mixed quantum/classical theory of rotationally and vibrationally inelastic scattering in space-fixed and body-fixed reference frames.
Science.gov (United States)
Semenov, Alexander; Babikov, Dmitri
2013-11-07
We formulated the mixed quantum/classical theory for rotationally and vibrationally inelastic scattering process in the diatomic molecule + atom system. Two versions of theory are presented, first in the space-fixed and second in the body-fixed reference frame. First version is easy to derive and the resultant equations of motion are transparent, but the state-to-state transition matrix is complex-valued and dense. Such calculations may be computationally demanding for heavier molecules and/or higher temperatures, when the number of accessible channels becomes large. In contrast, the second version of theory requires some tedious derivations and the final equations of motion are rather complicated (not particularly intuitive). However, the state-to-state transitions are driven by real-valued sparse matrixes of much smaller size. Thus, this formulation is the method of choice from the computational point of view, while the space-fixed formulation can serve as a test of the body-fixed equations of motion, and the code. Rigorous numerical tests were carried out for a model system to ensure that all equations, matrixes, and computer codes in both formulations are correct.
4. Mixed quantum/classical theory of rotationally and vibrationally inelastic scattering in space-fixed and body-fixed reference frames
International Nuclear Information System (INIS)
Semenov, Alexander; Babikov, Dmitri
2013-01-01
We formulated the mixed quantum/classical theory for rotationally and vibrationally inelastic scattering process in the diatomic molecule + atom system. Two versions of theory are presented, first in the space-fixed and second in the body-fixed reference frame. First version is easy to derive and the resultant equations of motion are transparent, but the state-to-state transition matrix is complex-valued and dense. Such calculations may be computationally demanding for heavier molecules and/or higher temperatures, when the number of accessible channels becomes large. In contrast, the second version of theory requires some tedious derivations and the final equations of motion are rather complicated (not particularly intuitive). However, the state-to-state transitions are driven by real-valued sparse matrixes of much smaller size. Thus, this formulation is the method of choice from the computational point of view, while the space-fixed formulation can serve as a test of the body-fixed equations of motion, and the code. Rigorous numerical tests were carried out for a model system to ensure that all equations, matrixes, and computer codes in both formulations are correct
5. An Algorithm-Independent Analysis of the Quality of Images Produced Using Multi-Frame Blind Deconvolution Algorithms--Conference Proceedings (Postprint)
National Research Council Canada - National Science Library
Matson, Charles; Haji, Alim
2007-01-01
Multi-frame blind deconvolution (MFBD) algorithms can be used to generate a deblurred image of an object from a sequence of short-exposure and atmospherically-blurred images of the object by jointly estimating the common object...
6. Framing of health information messages.
Science.gov (United States)
Akl, Elie A; Oxman, Andrew D; Herrin, Jeph; Vist, Gunn E; Terrenato, Irene; Sperati, Francesca; Costiniuk, Cecilia; Blank, Diana; Schünemann, Holger
2011-12-07
The same information about the evidence on health effects can be framed either in positive words or in negative words. Some research suggests that positive versus negative framing can lead to different decisions, a phenomenon described as the framing effect. Attribute framing is the positive versus negative description of a specific attribute of a single item or a state, for example, "the chance of survival with cancer is 2/3" versus "the chance of mortality with cancer is 1/3". Goal framing is the description of the consequences of performing or not performing an act as a gain versus a loss, for example, "if you undergo a screening test for cancer, your survival will be prolonged" versus "if you don't undergo screening test for cancer, your survival will be shortened". To evaluate the effects of attribute (positive versus negative) framing and of goal (gain versus loss) framing of the same health information, on understanding, perception of effectiveness, persuasiveness, and behavior of health professionals, policy makers, and consumers. We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, issue 3 2007), MEDLINE (Ovid) (1966 to October 2007), EMBASE (Ovid) (1980 to October 2007), PsycINFO (Ovid) (1887 to October 2007). There were no language restrictions. We reviewed the reference lists of related systematic reviews, included studies and of excluded but closely related studies. We also contacted experts in the field. We included randomized controlled trials, quasi-randomised controlled trials, and cross-over studies with health professionals, policy makers, and consumers evaluating one of the two types of framing. Two review authors extracted data in duplicate and independently. We graded the quality of evidence for each outcome using the GRADE approach. We standardized the outcome effects using standardized mean difference (SMD). We stratified the analysis by the type of framing (attribute, goal) and conducted pre
7. Stellar aberration correction and thermoelastic compensation of Swarm μASC attitude observations: A comment to the Express Letter “Mysterious misalignments between geomagnetic and stellar reference frames seen in CHAMP and Swarm satellite measurements”, by Stefan Maus
DEFF Research Database (Denmark)
Herceg, M.; Jørgensen, P. S.; Jørgensen, J. L.
2017-01-01
. However, comparison of the Inter Boresight Angle shows a relative attitude variation between the μASC Camera Head Units. These misalignments between Camera Head Units and a geomagnetic reference frame cannot be explained by incorrect aberration correction (as theorized by Maus). Herceg et al. found them...... and clean from any variation caused by thermoelastic effects....
8. Frames and semi-frames
International Nuclear Information System (INIS)
Antoine, Jean-Pierre; Balazs, Peter
2011-01-01
Loosely speaking, a semi-frame is a generalized frame for which one of the frame bounds is absent. More precisely, given a total sequence in a Hilbert space, we speak of an upper (resp. lower) semi-frame if only the upper (resp. lower) frame bound is valid. Equivalently, for an upper semi-frame, the frame operator is bounded, but has an unbounded inverse, whereas a lower semi-frame has an unbounded frame operator, with a bounded inverse. We study mostly upper semi-frames, both in the continuous and discrete case, and give some remarks for the dual situation. In particular, we show that reconstruction is still possible in certain cases.
9. Reference frame access under the effects of great earthquakes: a least squares collocation approach for non-secular post-seismic evolution
Science.gov (United States)
Gómez, D. D.; Piñón, D. A.; Smalley, R.; Bevis, M.; Cimbaro, S. R.; Lenzano, L. E.; Barón, J.
2016-03-01
The 2010, (Mw 8.8) Maule, Chile, earthquake produced large co-seismic displacements and non-secular, post-seismic deformation, within latitudes 28°S-40°S extending from the Pacific to the Atlantic oceans. Although these effects are easily resolvable by fitting geodetic extended trajectory models (ETM) to continuous GPS (CGPS) time series, the co- and post-seismic deformation cannot be determined at locations without CGPS (e.g., on passive geodetic benchmarks). To estimate the trajectories of passive geodetic benchmarks, we used CGPS time series to fit an ETM that includes the secular South American plate motion and plate boundary deformation, the co-seismic discontinuity, and the non-secular, logarithmic post-seismic transient produced by the earthquake in the Posiciones Geodésicas Argentinas 2007 (POSGAR07) reference frame (RF). We then used least squares collocation (LSC) to model both the background secular inter-seismic and the non-secular post-seismic components of the ETM at the locations without CGPS. We tested the LSC modeled trajectories using campaign and CGPS data that was not used to generate the model and found standard deviations (95 % confidence level) for position estimates for the north and east components of 3.8 and 5.5 mm, respectively, indicating that the model predicts the post-seismic deformation field very well. Finally, we added the co-seismic displacement field, estimated using an elastic finite element model. The final, trajectory model allows accessing the POSGAR07 RF using post-Maule earthquake coordinates within 5 cm for ˜ 91 % of the passive test benchmarks.
10. Drifting while stepping in place in old adults: Association of self-motion perception with reference frame reliance and ground optic flow sensitivity.
Science.gov (United States)
Agathos, Catherine P; Bernardin, Delphine; Baranton, Konogan; Assaiante, Christine; Isableu, Brice
2017-04-07
Optic flow provides visual self-motion information and is shown to modulate gait and provoke postural reactions. We have previously reported an increased reliance on the visual, as opposed to the somatosensory-based egocentric, frame of reference (FoR) for spatial orientation with age. In this study, we evaluated FoR reliance for self-motion perception with respect to the ground surface. We examined how effects of ground optic flow direction on posture may be enhanced by an intermittent podal contact with the ground, and reliance on the visual FoR and aging. Young, middle-aged and old adults stood quietly (QS) or stepped in place (SIP) for 30s under static stimulation, approaching and receding optic flow on the ground and a control condition. We calculated center of pressure (COP) translation and optic flow sensitivity was defined as the ratio of COP translation velocity over absolute optic flow velocity: the visual self-motion quotient (VSQ). COP translation was more influenced by receding flow during QS and by approaching flow during SIP. In addition, old adults drifted forward while SIP without any imposed visual stimulation. Approaching flow limited this natural drift and receding flow enhanced it, as indicated by the VSQ. The VSQ appears to be a motor index of reliance on the visual FoR during SIP and is associated with greater reliance on the visual and reduced reliance on the egocentric FoR. Exploitation of the egocentric FoR for self-motion perception with respect to the ground surface is compromised by age and associated with greater sensitivity to optic flow. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.
11. Changing climate, changing frames
International Nuclear Information System (INIS)
Vink, Martinus J.; Boezeman, Daan; Dewulf, Art; Termeer, Catrien J.A.M.
2013-01-01
Highlights: ► We show development of flood policy frames in context of climate change attention. ► Rising attention on climate change influences traditional flood policy framing. ► The new framing employs global-scale scientific climate change knowledge. ► With declining attention, framing disregards climate change, using local knowledge. ► We conclude that frames function as sensemaking devices selectively using knowledge. -- Abstract: Water management and particularly flood defence have a long history of collective action in low-lying countries like the Netherlands. The uncertain but potentially severe impacts of the recent climate change issue (e.g. sea level rise, extreme river discharges, salinisation) amplify the wicked and controversial character of flood safety policy issues. Policy proposals in this area generally involve drastic infrastructural works and long-term investments. They face the difficult challenge of framing problems and solutions in a publicly acceptable manner in ever changing circumstances. In this paper, we analyse and compare (1) how three key policy proposals publicly frame the flood safety issue, (2) the knowledge referred to in the framing and (3) how these frames are rhetorically connected or disconnected as statements in a long-term conversation. We find that (1) framings of policy proposals differ in the way they depict the importance of climate change, the relevant timeframe and the appropriate governance mode; (2) knowledge is selectively mobilised to underpin the different frames and (3) the frames about these proposals position themselves against the background of the previous proposals through rhetorical connections and disconnections. Finally, we discuss how this analysis hints at the importance of processes of powering and puzzling that lead to particular framings towards the public at different historical junctures
12. Social scaling of extrapersonal space: target objects are judged as closer when the reference frame is a human agent with available movement potentialities.
Science.gov (United States)
Fini, C; Brass, M; Committeri, G
2015-01-01
Space perception depends on our motion potentialities and our intended actions are affected by space perception. Research on peripersonal space (the space in reaching distance) shows that we perceive an object as being closer when we (Witt, Proffitt, & Epstein, 2005; Witt & Proffitt, 2008) or another actor (Costantini, Ambrosini, Sinigaglia, & Gallese, 2011; Bloesch, Davoli, Roth, Brockmole, & Abrams, 2012) can interact with it. Similarly, an object only triggers specific movements when it is placed in our peripersonal space (Costantini, Ambrosini, Tieri, Sinigaglia, & Committeri, 2010) or in the other's peripersonal space (Costantini, Committeri, & Sinigaglia, 2011; Cardellicchio, Sinigaglia, & Costantini, 2013). Moreover, also the extrapersonal space (the space outside reaching distance) seems to be perceived in relation to our movement capabilities: the more effort it takes to cover a distance, the greater we perceive the distance to be (Proffitt, Stefanucci, Banton, & Epstein, 2003; Sugovic & Witt, 2013). However, not much is known about the influence of the other's movement potentialities on our extrapersonal space perception. Three experiments were carried out investigating the categorization of distance in extrapersonal space using human or non-human allocentric reference frames (RF). Subjects were asked to judge the distance ("Near" or "Far") of a target object (a beach umbrella) placed at progressively increasing or decreasing distances until a change from near to far or vice versa was reported. In the first experiment we found a significant "Near space extension" when the allocentric RF was a human virtual agent instead of a static, inanimate object. In the second experiment we tested whether the "Near space extension" depended on the anatomical structure of the RF or its movement potentialities by adding a wooden dummy. The "Near space extension" was only observed for the human agent but not for the dummy. Finally, to rule out the possibility that the
13. Framing theory
NARCIS (Netherlands)
de Vreese, C.H.; Lecheler, S.; Mazzoleni, G.; Barnhurst, K.G.; Ikeda, K.; Maia, R.C.M.; Wessler, H.
2016-01-01
Political issues can be viewed from different perspectives and they can be defined differently in the news media by emphasizing some aspects and leaving others aside. This is at the core of news framing theory. Framing originates within sociology and psychology and has become one of the most used
14. On Framing
DEFF Research Database (Denmark)
Peder Pedersen, Claus
2018-01-01
On framing as artistic and conceptual tool in the works of Claudia Carbone. Contribution to exhibition at the Aarhus School of Architecture.......On framing as artistic and conceptual tool in the works of Claudia Carbone. Contribution to exhibition at the Aarhus School of Architecture....
15. Framing politics
NARCIS (Netherlands)
Lecheler, S.K.
2010-01-01
This dissertation supplies a number of research findings that add to a theory of news framing effects, and also to the understanding of the role media effects play in political communication. We show that researchers must think more about what actually constitutes a framing effect, and that a
16. A 5 V-to-3.3 V CMOS Linear Regulator with Three-Output Temperature-Independent Reference Voltages
Directory of Open Access Journals (Sweden)
San-Fu Wang
2016-01-01
Full Text Available This paper presents a 5 V-to-3.3 V linear regulator circuit, which uses 3.3 V CMOS transistors to replace the 5 V CMOS transistors. Thus, the complexity of the manufacturing semiconductor process can be improved. The proposed linear regulator is implemented by cascode architecture, which requires three different reference voltages as the bias voltages of its circuit. Thus, the three-output temperature-independent reference voltage circuit is proposed, which provides three accurate reference voltages simultaneously. The three-output temperature-independent reference voltages also can be used in other circuits of the chip. By using the proposed temperature-independent reference voltages, the proposed linear regulator can provide an accurate output voltage, and it is suitable for low cost, small size, and highly integrated system-on-chip (SoC applications. Moreover, the proposed linear regulator uses the cascode technique, which improves both the gain performance and the isolation performance. Therefore, the proposed linear regulator has a good performance in reference voltage to output voltage isolation. The voltage variation of the linear regulator is less than 2.153% in the temperature range of −40°C–120°C, and the power supply rejection ratio (PSRR is less than −42.8 dB at 60 Hz. The regulator can support 0~200 mA output current. The core area is less than 0.16 mm2.
17. Competitive Framing
OpenAIRE
Ran Spiegler
2014-01-01
I present a simple framework for modeling two-firm market competition when consumer choice is "frame-dependent", and firms use costless "marketing messages" to influence the consumer's frame. This framework embeds several recent models in the "behavioral industrial organization" literature. I identify a property that consumer choice may satisfy, which extends the concept of Weighted Regularity due to Piccione and Spiegler (2012), and provide a characterization of Nash equilibria under this pr...
18. Quotation and Framing
DEFF Research Database (Denmark)
Petersen, Nils Holger
2010-01-01
. In Black Angels the composer – among other well-known pieces of music – quotes the medieval dies irae sequence and the second movement of Schubert’s string quartet in D minor (D. 810). The musical and intermedial references are framed with striking modernistic sounds exploring instrumental possibilities...
19. Framing the evidence for health smart homes and home-based consumer health technologies as a public health intervention for independent aging: a systematic review.
Science.gov (United States)
Reeder, Blaine; Meyer, Ellen; Lazar, Amanda; Chaudhuri, Shomir; Thompson, Hilaire J; Demiris, George
2013-07-01
There is a critical need for public health interventions to support the independence of older adults as the world's population ages. Health smart homes (HSH) and home-based consumer health (HCH) technologies may play a role in these interventions. We conducted a systematic review of HSH and HCH literature from indexed repositories for health care and technology disciplines (e.g., MEDLINE, CINAHL, and IEEE Xplore) and classified included studies according to an evidence-based public health (EBPH) typology. One thousand, six hundred and thirty-nine candidate articles were identified. Thirty-one studies from the years 1998-2011 were included. Twenty-one included studies were classified as emerging, 10 as promising and 3 as effective (first tier). The majority of included studies were published in the period beginning in the year 2005. All 3 effective (first tier) studies and 9 of 10 of promising studies were published during this period. Almost all studies included an activity sensing component and most of them used passive infrared motion sensors. The three effective (first tier) studies all used a multicomponent technology approach that included activity sensing, reminders and other technologies tailored to individual preferences. Future research should explore the use of technology for self-management of health by older adults; social support; and self-reported health measures incorporated into personal health records, electronic medical records, and community health registries. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
CERN Document Server
Han, Deguang; Larson, David; Weber, Eric
2007-01-01
Frames for Undergraduates is an undergraduate-level introduction to the theory of frames in a Hilbert space. This book can serve as a text for a special-topics course in frame theory, but it could also be used to teach a second semester of linear algebra, using frames as an application of the theoretical concepts. It can also provide a complete and helpful resource for students doing undergraduate research projects using frames. The early chapters contain the topics from linear algebra that students need to know in order to read the rest of the book. The later chapters are devoted to advanced topics, which allow students with more experience to study more intricate types of frames. Toward that end, a Student Presentation section gives detailed proofs of fairly technical results with the intention that a student could work out these proofs independently and prepare a presentation to a class or research group. The authors have also presented some stories in the Anecdotes section about how this material has moti...
1. Mixed quantum/classical theory for inelastic scattering of asymmetric-top-rotor + atom in the body-fixed reference frame and application to the H₂O + He system.
Science.gov (United States)
Semenov, Alexander; Dubernet, Marie-Lise; Babikov, Dmitri
2014-09-21
The mixed quantum/classical theory (MQCT) for inelastic molecule-atom scattering developed recently [A. Semenov and D. Babikov, J. Chem. Phys. 139, 174108 (2013)] is extended to treat a general case of an asymmetric-top-rotor molecule in the body-fixed reference frame. This complements a similar theory formulated in the space-fixed reference-frame [M. Ivanov, M.-L. Dubernet, and D. Babikov, J. Chem. Phys. 140, 134301 (2014)]. Here, the goal was to develop an approximate computationally affordable treatment of the rotationally inelastic scattering and apply it to H2O + He. We found that MQCT is somewhat less accurate at lower scattering energies. For example, below E = 1000 cm(-1) the typical errors in the values of inelastic scattering cross sections are on the order of 10%. However, at higher scattering energies MQCT method appears to be rather accurate. Thus, at scattering energies above 2000 cm(-1) the errors are consistently in the range of 1%-2%, which is basically our convergence criterion with respect to the number of trajectories. At these conditions our MQCT method remains computationally affordable. We found that computational cost of the fully-coupled MQCT calculations scales as n(2), where n is the number of channels. This is more favorable than the full-quantum inelastic scattering calculations that scale as n(3). Our conclusion is that for complex systems (heavy collision partners with many internal states) and at higher scattering energies MQCT may offer significant computational advantages.
2. Framing scales and scaling frames
NARCIS (Netherlands)
van Lieshout, M.; Dewulf, A.; Aarts, N.; Termeer, K.
2009-01-01
Policy problems are not just out there. Actors highlight different aspects of a situation as problematic and situate the problem on different scales. In this study we will analyse the way actors apply scales in their talk (or texts) to frame the complex decision-making process of the establishment
3. Framing Innovation
DEFF Research Database (Denmark)
Haase, Louise Møller; Laursen, Linda Nhu
2017-01-01
Designing a remarkable product innovation is a difficult challenge, which businesses today continuously are striving to tackle. This challenge is particularly present in the early phase of innovation, where the main product concept and frames of the innovation is determined. As a main challenge...... in the early phase is the reasoning process; innovation team are faced with open-ended ill-defines problems, where they need to make decisions about an unknown future having only incomplete, ambiguous and contradicting insights available. We study the reasoning of experts, how they frame to make sense of all...... the insights and create a basis for decision making in relation to a new project. Based on case studies of five innovative products from various industries, we suggest a Product Reasoning Model for understanding reasoning and envisioning of new product innovations in the early phases...
4. Framing Innovation
DEFF Research Database (Denmark)
Haase, Louise Møller; Laursen, Linda Nhu
2017-01-01
Designing a remarkable product innovation is a difficult challenge, which businesses today continuously are striving to tackle. This challenge is particularly present in the early phase of innovation, where the main product concept and frames of the innovation is determined. As a main challenge...... in the early phase is the reasoning process; innovation team are faced with open- ended ill-defines problems, where they need to make decisions about an unknown future having only incomplete, ambiguous and contradicting insights available. We study the reasoning of experts, how they frame to make sense of all...... the insights and create a basis for decision making in relation to a new project. Based on case studies of five innovative products from various industries, we suggest a Product Reasoning Model for understanding reasoning and envisioning of new product innovations in the early phases of innovation....
5. A new reference frame for astronomically-tuned Plio-Pleistocene climate variability derived from a benthic oxygen isotope splice of the Mediterranean
Science.gov (United States)
Lourens, L. J.; Ziegler, M.; Konijnendijk, T. Y. M.; Hilgen, F. J.; Bos, R.; Beekvelt, B.; van Loevezijn, A.; Collin, S.
2017-12-01
The astronomical theory of climate has revolutionized our understanding of past climate change and the development of highly accurate geologic time scales for the entire Cenozoic. Most of this understanding has come from the construction of astronomically tuned global ocean benthic foraminiferal oxygen isotope (δ18O) stacked record, derived by the international drilling operations of DSDP, ODP and IODP. The tuning includes fixed phase relationships between the obliquity and precession cycles and the inferred high-latitude climate, i.e. glacial-interglacial, response, which hark back to SPECMAP, using simple ice sheet models and a limited number of radiometric dates. This approach was largely implemented in the widely applied LR04 stack, though LR04 assumed shorter response times for the smaller ice caps during the Pliocene. In the past decades, an astronomically calibrated time scale for the Pliocene and Pleistocene of the Mediterranean has been developed, which has become the reference for the standard Geologic Time Scale. Typical of the Mediterranean marine sediments are the cyclic lithological alternations, reflecting the interference between obliquity and precession-paced low latitude climate variability, such as the African monsoon. Here we present the first benthic foraminiferal based oxygen isotope record of the Mediterranean reference scale, which strikingly mirrors the LR04. We will use this record to discuss the assumed open ocean glacial-interglacial related phase relations over the past 5.3 million years.
6. Frame by Frame II: A Filmography of the African American Image, 1978-1994.
Science.gov (United States)
Klotman, Phyllis R.; Gibson, Gloria J.
A reference guide on African American film professionals, this book is a companion volume to the earlier "Frame by Frame I." It focuses on giving credit to African Americans who have contributed their talents to a film industry that has scarcely recognized their contributions, building on the aforementioned "Frame by Frame I,"…
7. The Mediterranean Plio-Pleistocene: A reference frame for astronomically paced low and high latitude climate changes (Jean Baptiste Lamarck Medal Lecture)
Science.gov (United States)
Lourens, Lucas
2016-04-01
The astronomical theory of climate has revolutionized our understanding of past climate change and the development of highly accurate geologic time scales for the entire Cenozoic. Most of this understanding has started with the construction of high-resolution stable oxygen isotope (18O) records from planktonic and benthic foraminifera of open ocean deep marine sediments explored by the international drilling operations of DSDP, ODP and IODP. These efforts culminated into global ocean isotopic stacked records, which give a clear picture of the evolution of the climate state through time. Fundamental for these reconstructions are the assumptions made between the astronomical forcing and the tuned time series and the accuracy of the astronomical solution. In the past decades, an astronomically calibrated time scale for the Pliocene and Pleistocene of the Mediterranean has been developed, which has become the reference for the standard Geologic Time Scale. Characteristic of the studied marine sediments are the cyclic lithological alternations, reflecting the interference between obliquity and precession-paced low latitude climate variability. These interference patterns allowed to evaluate the accuracy of astronomical solutions and to constrain the dynamical ellipticity of the Earth and tidal dissipation by the Sun and the Moon, which in turn provided the backbone for the widely applied LR04 open ocean benthic isotope stack of the past 5 Myr. So far, the assumed time lags between orbital forcing and the global climate response as reflected in LR04 have not been tested, while these assumptions hark back to SPECMAP, using simple ice sheet models and a limited number of radiometric dates. In addition, LR04 adopted a shorter response time for the smaller ice caps during the Pliocene. Here I present the first benthic 18O record of the Mediterranean reference scale, which strikingly mirrors the LR04. I will use this record to discuss the assumed phase relations and its
8. Work and Inertial Frames
Science.gov (United States)
Kaufman, Richard
2017-12-01
A fairly recent paper resolves a large discrepancy in the internal energy utilized to fire a cannon as calculated by two inertial observers. Earth and its small reaction velocity must be considered in the system so that the change in kinetic energy is calculated correctly. This paper uses a car in a similar scenario, but considers the work done by forces acting over distances. An analysis of the system must include all energy interactions, including the work done on the car and especially the (negative) work done on Earth in a moving reference frame. This shows the importance of considering the force on Earth and the distance Earth travels. For calculation of work in inertial reference frames, the center of mass perspective is shown to be useful. We also consider the energy requirements to efficiently accelerate a mass among interacting masses.
9. Gauge Invariance and Frame Independence in Cosmology
NARCIS (Netherlands)
Weenink, J.G.
2013-01-01
In this thesis the mathematical formulation of cosmological perturbations is studied. First we discuss the gauge problem of general relativity: perturbations of the metric and matter fields in an expanding universe are dependent on the choice of coordinate system, i.e. gauge dependent, even though
10. Framing Suicide - Investigating the News Media and Public's Use of the Problematic Suicide Referents Freitod and Selbstmord in German-Speaking Countries.
Science.gov (United States)
Arendt, Florian
2018-01-01
In German-speaking countries, suicide experts recommend not using the suicide referents Freitod and Selbstmord, as their associative meanings relate to problematic concepts such as free will and crime. To investigate which terms - the neutral and recommended Suizid or Freitod and Selbstmord - have dominated news coverage and to reveal what terms the public actually used. A retrospective database study was undertaken on data from the period 2004-2016. First, we investigated how frequently the terms were used in news coverage via an automated content analysis. Second, we investigated how often individuals used the terms for information-seeking via Google's search engine, since it can be used as an indicator of the popularity of a given term within a given period. Analyses revealed that Selbstmord was the most frequently used term in the news and by the public. Importantly, the use of Suizid increased in both datasets, nearly approaching the Selbstmord level in the later years. Although on a low level, the highly problematic term Freitod has also been in regular use. Media interventions should continue trying to increase journalists' awareness so that they use appropriate terms when reporting on suicide.
11. Marco de referencia conceptual para la construcción de ambientes virtuales de enseñanza y aprendizaje / Frame of Conceptual Reference to the Construction of Virtual Environments of Education And Of Learning
Directory of Open Access Journals (Sweden)
Maria Elena Giraldo Ramirez
2007-01-01
Full Text Available Este texto pretende dar cuenta del marco de referencia conceptual que soporta los trabajos investigativos del Grupo EAV en torno al tema de la educación virtual y de las tecnologías de información y comunicación. Este marco plantea dos enfoques, el primero, un enfoque antropológico, para acercarse a la comprensión de la relación Tecnología-Comunicación-Educación que reconocemos como la tríada; y el segundo, un enfoque comunicacional que despliega la tríada contemporánea desde dos principios conceptuales: la mediación y la interacción.This paper tries to realize of the frame of conceptual reference that supports the works of research of the Group EAV around the topic of the virtual education and of the technologies of information and communication. This frame raises two approaches, the first one, an anthropologic approach, to approach the comprehension of the relation Technology, Communication and Education that we recognize as the triad; and the second one, a communication approach that develops the contemporary triad from two conceptual principles: the mediation and the interaction.
12. Single-leg squats identify independent stair negotiation ability in older adults referred for a physiotherapy mobility assessment at a rural hospital.
Science.gov (United States)
Hockings, Rowena L; Schmidt, David D; Cheung, Christopher W
2013-07-01
13. On Safety Management. A Frame of Reference for Studies of Safety Management with Examples From Non-Nuclear Contexts of Relevance for Nuclear Safety
Energy Technology Data Exchange (ETDEWEB)
Svensson, Ola; Salo, Ilkka; Allwin, Pernilla (Risk Analysis, Social and Decision Research Unit, Dept. of Psychology, Stockholm Univ., Stockholm (Sweden))
2004-11-15
A good knowledge about safety management from risk technologies outside the area of nuclear power may contribute to both broaden the perspectives on safety management in general, and point at new opportunities for improving safety measures within the nuclear industry. First, a theoretical framework for the study of safety management in general is presented, followed by three case studies on safety management from different non-nuclear areas with potential relevance for nuclear safety. The chapters are written as separate reports and can be read independently of each other. The nuclear industry has a long experience about the management of risky activities, involving all the stages from planing to implementation, both on a more generalized level and in the specific branches of activities (management, administration, operation, maintenance, etc.). Here, safety management is a key concept related to these areas of activities. Outside the field of nuclear power there exist a number of different non-nuclear risk technologies, each one with their own specific needs and experiences about safety management. The differences between the areas consist partly of the different experiences caused by the different technologies. Besides using own experiences in safety practices within the own areas of activities, it may be profitable to take advantage in knowledge and experiences from one area and put it in practice in another area. In order to facilitate knowledge transfer from one technological area to another it may be possible to adapt a common theoretical model, for descriptions and explanations, to the different technologies. Such a model should admit that common denominators for safety management across the areas might be identified and described with common concepts. Systems theory gives the opportunity to not only create models that are descriptive for events within the limits of a given technology, but also to generate knowledge that can be transferred to other
14. Modeling laser wakefield accelerators in a Lorentz boosted frame
Energy Technology Data Exchange (ETDEWEB)
Vay, J.-L.; Geddes, C.G.R.; Cormier-Michel, E.; Grotec, D. P.
2010-06-15
Modeling of laser-plasma wakefield accelerators in an optimal frame of reference is shown to produce orders of magnitude speed-up of calculations from first principles. Obtaining these speedups requires mitigation of a high-frequency instability that otherwise limits effectiveness in addition to solutions for handling data input and output in a relativistically boosted frame of reference. The observed high-frequency instability is mitigated using methods including an electromagnetic solver with tunable coefficients, its extension to accomodate Perfectly Matched Layers and Friedman's damping algorithms, as well as an efficient large bandwidth digital filter. It is shown that choosing the frame of the wake as the frame of reference allows for higher levels of filtering and damping than is possible in other frames for the same accuracy. Detailed testing also revealed serendipitously the existence of a singular time step at which the instability level is minimized, independently of numerical dispersion, thus indicating that the observed instability may not be due primarily to Numerical Cerenkov as has been conjectured. The techniques developed for Cerenkov mitigation prove nonetheless to be very efficient at controlling the instability. Using these techniques, agreement at the percentage level is demonstrated between simulations using different frames of reference, with speedups reaching two orders of magnitude for a 0.1 GeV class stages. The method then allows direct and efficient full-scale modeling of deeply depleted laser-plasma stages of 10 GeV-1 TeV for the first time, verifying the scaling of plasma accelerators to very high energies. Over 4, 5 and 6 orders of magnitude speedup is achieved for the modeling of 10 GeV, 100 GeV and 1 TeV class stages, respectively.
15. Modeling laser wakefield accelerators in a Lorentz boosted frame
International Nuclear Information System (INIS)
Vay, J.-L.; Geddes, C.G.R.; Cormier-Michel, E.; Grote, D.P.
2010-01-01
Modeling of laser-plasma wakefield accelerators in an optimal frame of reference (1) is shown to produce orders of magnitude speed-up of calculations from first principles. Obtaining these speedups requires mitigation of a high frequency instability that otherwise limits effectiveness in addition to solutions for handling data input and output in a relativistically boosted frame of reference. The observed high-frequency instability is mitigated using methods including an electromagnetic solver with tunable coefficients, its extension to accommodate Perfectly Matched Layers and Friedman's damping algorithms, as well as an efficient large bandwidth digital filter. It is shown that choosing the frame of the wake as the frame of reference allows for higher levels of filtering and damping than is possible in other frames for the same accuracy. Detailed testing also revealed serendipitously the existence of a singular time step at which the instability level is minimized, independently of numerical dispersion, thus indicating that the observed instability may not be due primarily to Numerical Cerenkov as has been conjectured. The techniques developed for Cerenkov mitigation prove nonetheless to be very efficient at controlling the instability. Using these techniques, agreement at the percentage level is demonstrated between simulations using different frames of reference, with speedups reaching two orders of magnitude for a 0.1 GeV class stages. The method then allows direct and efficient full-scale modeling of deeply depleted laser-plasma stages of 10 GeV-1 TeV for the first time, verifying the scaling of plasma accelerators to very high energies. Over 4, 5 and 6 orders of magnitude speedup is achieved for the modeling of 10 GeV, 100 GeV and 1 TeV class stages, respectively.
16. Cognitive Frames of Reference and Strategic Thinking
Science.gov (United States)
1991-04-05
Elliot Jaques and T. 0. Jacobs, whose Stratified Systems Theory (SST) links leadership requirements to organizational functions. SST emphasizes the...Strategic Managers , pp. 6-14. 6. Isenberg, p. 172; Jacobs and Jaques; J. G. Hunt, Toward Leadership Paradigm Expansion. 7. C. J. Whitehead and K. B...reverse if necessary and identify by block number) Using Stratified Systems Theory and the research on expertise as a conceptual framework, this study
17. The Electromotive Force in Different Reference Frames
Science.gov (United States)
2018-05-01
The electromotive force (EMF) is the work per unit charge around a wire loop caused by a time-varying magnetic flux threading the loop. It is due to a force moving the charges around the loop. This is true whether the change in flux is due to the wire loop being stationary and the field changing in time, or the loop moving through a spatially varying field. In the first case, we say that the time-varying magnetic field induces an electric field that provides the force; in the second, we say that the force is due to the magnetic field acting on the charges in the moving loop. The theory of relativity states that both viewpoints must be equivalent, but it is sometimes difficult to harmonize them.
18. A frame of reference for SOA migration
NARCIS (Netherlands)
Razavian, M.; Lago, P.; Di Nitto, E.; Yahyapour, R.
2010-01-01
Migration of legacy systems to service-based systems constitutes a key challenge of service-oriented system engineering, namely rehabilitation of pre-existing enterprise assets while conforming to service engineering principles. Over a decade there has been an increasing interest in the approaches
19. A Frame of Reference for SOA Migration
NARCIS (Netherlands)
Razavian, M.; Lago, P.; Elisabetta Di Nitto,; Ramin Yahyapour,
2010-01-01
Migration of legacy systems to service-based systems constitutes a key challenge of service-oriented system engineering, namely rehabilitation of pre-existing enterprise assets while conforming to service engineering principles. Over a decade there has been an increasing interest in the approaches
20. Stimulus reference frame and neural coding precision
Czech Academy of Sciences Publication Activity Database
Košťál, Lubomír
2016-01-01
Roč. 71, Apr 2016 (2016), s. 22-27 ISSN 0022-2496 R&D Projects: GA ČR(CZ) GA15-08066S Institutional support: RVO:67985823 Keywords : Fisher information * coding accuracy * measurement scale * Jeffreys prior Subject RIV: FH - Neurology Impact factor: 1.377, year: 2016
1. Moderating Effects of Consumer Involvement and the Need for Cognition on Goal Framing
Directory of Open Access Journals (Sweden)
Leandro Miletto Tonetto
2010-01-01
Full Text Available Goal framing effect refers to the finding that different ways of presenting the same communication content to a consumer tends to generate distinct levels of persuasion for the emitted message. This research is aimed at investigating the interaction between goal framing effect, consumer involvement and the Need for Cognition (NfC on consumer decision making. Two experiments have been carried out to test the hypothesis that the level of persuasion for a promotional text elevates as consumer involvement increases, independent of the message frame or the NfC. Results showed that consumer's involvement seemed to draw the text's persuasion level up, as it increases, or down, as it decreases, independent of the text frame and the NfC.
2. [The framing effect: medical implications].
Science.gov (United States)
Mazzocco, Ketti; Cherubini, Paolo; Rumiati, Rino
2005-01-01
Over the last 20 years, many studies explored how the way information is presented modifies choices. This sort of effect, referred to as "framing effects", typically consists of the inversion of choices when presenting structurally identical decision problems in different ways. It is a common assumption that physicians are unaffected (or less affected) by the surface description of a decision problem, because they are formally trained in medical decision making. However, several studies showed that framing effects occur even in the medical field. The complexity and variability of these effects are remarkable, making it necessary to distinguish among different framing effects, depending on whether the effect is obtained by modifying adjectives (attribute framing), goals of a behavior (goal framing), or the probability of an outcome (risky choice framing). A further reason for the high variability of the framing effects seems to be the domain of the decision problem, with different effects occurring in prevention decisions, disease-detection decisions, and treatment decisions. The present work reviews the studies on framing effects, in order to summarize them and clarify their possible role in medical decision making.
3. Pseudo-set framing.
Science.gov (United States)
Barasz, Kate; John, Leslie K; Keenan, Elizabeth A; Norton, Michael I
2017-10-01
Pseudo-set framing-arbitrarily grouping items or tasks together as part of an apparent "set"-motivates people to reach perceived completion points. Pseudo-set framing changes gambling choices (Study 1), effort (Studies 2 and 3), giving behavior (Field Data and Study 4), and purchase decisions (Study 5). These effects persist in the absence of any reward, when a cost must be incurred, and after participants are explicitly informed of the arbitrariness of the set. Drawing on Gestalt psychology, we develop a conceptual account that predicts what will-and will not-act as a pseudo-set, and defines the psychological process through which these pseudo-sets affect behavior: over and above typical reference points, pseudo-set framing alters perceptions of (in)completeness, making intermediate progress seem less complete. In turn, these feelings of incompleteness motivate people to persist until the pseudo-set has been fulfilled. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
4. Symmetries of collective models in intrinsic frame
International Nuclear Information System (INIS)
Gozdz, A.; Pedrak, A.; Szulerecka, A.; Dobrowolski, A.; Dudek, J.
2013-01-01
In the paper a very general definition of intrinsic frame, by means of group theoretical methods, is introduced. It allows to analyze nuclear properties which are invariant in respect to the group which defines the intrinsic frame. For example, nuclear shape is a well determined feature in the intrinsic frame defined by the Euclidean group. It is shown that using of intrinsic frame gives an opportunity to consider intrinsic nuclear symmetries which are independent of symmetries observed in the laboratory frame. An importance of the notion of partial symmetries is emphasized. (author)
5. On frame multiresolution analysis
DEFF Research Database (Denmark)
Christensen, Ole
2003-01-01
We use the freedom in frame multiresolution analysis to construct tight wavelet frames (even in the case where the refinable function does not generate a tight frame). In cases where a frame multiresolution does not lead to a construction of a wavelet frame we show how one can nevertheless...
6. Modeling laser wakefield accelerators in a Lorentz boosted frame
Energy Technology Data Exchange (ETDEWEB)
Vay, J.-L.; Geddes, C.G.R.; Cormier-Michel, E.; Grote, D.P.
2010-09-15
Modeling of laser-plasma wakefield accelerators in an optimal frame of reference [1] is shown to produce orders of magnitude speed-up of calculations from first principles. Obtaining these speedups requires mitigation of a high frequency instability that otherwise limits effectiveness in addition to solutions for handling data input and output in a relativistically boosted frame of reference. The observed high-frequency instability is mitigated using methods including an electromagnetic solver with tunable coefficients, its extension to accomodate Perfectly Matched Layers and Friedman's damping algorithms, as well as an efficient large bandwidth digital filter. It is shown that choosing theframe of the wake as the frame of reference allows for higher levels of filtering and damping than is possible in other frames for the same accuracy. Detailed testing also revealed serendipitously the existence of a singular time step at which the instability level is minimized, independently of numerical dispersion, thus indicating that the observed instability may not be due primarily to Numerical Cerenkov as has been conjectured. The techniques developed for Cerenkov mitigation prove nonetheless to be very efficient at controlling the instability. Using these techniques, agreement at the percentage level is demonstrated between simulations using different frames of reference, with speedups reaching two orders of magnitude for a 0.1 GeV class stages. The method then allows direct and efficient full-scale modeling of deeply depleted laser-plasma stages of 10 GeV-1 TeV for the first time, verifying the scaling of plasma accelerators to very high energies. Over 4, 5 and 6 orders of magnitude speedup is achieved for the modeling of 10 GeV, 100 GeV and 1 TeV class stages, respectively.
7. Molecular frame and recoil frame angular distributions in dissociative photoionization of small molecules
International Nuclear Information System (INIS)
Lucchese, R R; Carey, R; Elkharrat, C; Houver, J C; Dowek, D
2008-01-01
Photoelectron angular distributions in the dipole approximation can be written with respect to several different reference frames. A brief review of the molecular frame and recoil frame are given. Experimentally, one approach for obtaining such angular distributions is through angle-resolved coincidence measurements of dissociative ionization. If the system dissociates into two heavy fragments, then the recoil frame angular distribution can be measured. Computed molecular frame and recoil frame photoelectron angular distributions are compared to experimental data for the Cl 2p ionization of CH 3 Cl.
8. Another frame, another game? : Explaining framing effects in economic games
NARCIS (Netherlands)
Gerlach, Philipp; Jaeger, B.; Hopfensitz, A.; Lori, E.
2016-01-01
Small changes in the framing of games (i.e., the way in which the game situation is described to participants) can have large effects on players' choices. For example, referring to a prisoner's dilemma game as the "Community Game" as opposed to the "Wall Street Game" can double the cooperation rate
9. Nonmonotonic belief state frames and reasoning frames
NARCIS (Netherlands)
Engelfriet, J.; Herre, H.; Treur, J.
1995-01-01
In this paper five levels of specification of nonmonotonic reasoning are distinguished. The notions of semantical frame, belief state frame and reasoning frame are introduced and used as a semantical basis for the first three levels. Moreover, the semantical connections between the levels are
10. O-(2-[18F]fluoroethyl)-L-tyrosine uptake is an independent prognostic determinant in patients with glioma referred for radiation therapy
International Nuclear Information System (INIS)
Sweeney, Reinhart; Polat, Bülent; Flentje, Michael; Samnick, Samuel; Reiners, Christoph; Verburg, Frederik A.
2014-01-01
To evaluate the prognostic value of O-(2-[ 18 F]fluoroethyl)-L-tyrosine positron emission tomography (FET-PET) uptake intensity in World Health Organization (WHO) tumor grade II-IV gliomas. We studied 28 patients with WHO tumor grade II-IV gliomas who were referred to our department for radiation therapy. We acquired a FET-PET in all patients, as well as magnetic resonance imaging (MRI) of the brain consisting of at least T2-weighted imaging, flair and pre- and post-contrast T1-weighted imaging. SUVmax was measured and the tumor-to-brain uptake ratio (TBR) of all lesions was calculated based on the SUVmax (TBRmax) or SUVmean (TBRmean) of the contralateral healthy tissue. For this study, volumes were calculated using MRI alone, MRI + the volume with a SUVmax on FET-PET ≥ 2.2 as well as MRI + the volume with an uptake of at least 40% of the SUVmax. Tumor volumes were a median (range) of 88.6 (2.6-467.4) ml (MRI alone), 84.2 (2.8-474.4) ml (MRI + SUVmax on FET-PET ≥ 2.2) and 101.5 (4.0-512.1) ml (MRI + FET-PET uptake ≥ 40% SUVmax), respectively. TBR-SUVmean was 2.36 (1.46-4.08); TBR-SUVmax was 1.71 (0.97-2.85). During a follow-up of 18.7 (2.5-36.1) months after FET-PET, 12 patients died of malignant glioma. Patients with a SUVmax ≥ 2.6 had a significantly worse tumor-related mortality (p=0.005) and progression-free survival (p=0.038) than those with a lower SUVmax. Multivariate analysis showed that WHO tumor grade (p=0.001) and SUVmax ≥ 2.6 (p < 0.001) were independent predictors for tumor-related mortality, but not tumor volume or TBRmax or TBRmean. SUVmax ≥ 2.6 (p=0.007) and being treated for a recurrence rather than for a primary tumor manifestation (p=0.014) were predictors for progression-free survival, but not TBRmax or TBRmean. In this heterogeneous patient population, higher tracer uptake in FET-PET appears to be associated with a worse tumor-related mortality and a shorter duration of the disease-free interval. (author)
11. Geodetic precession or dragging of inertial frames?
International Nuclear Information System (INIS)
Ashby, N.; Shahid-Saless, B.
1990-01-01
In metric theories of gravity the principle of general covariance allows one to describe phenomena by means of any convenient choice of coordinate system. In this paper it is shown that in an appropriately chosen coordinate system, geodetic precession of a gyroscope orbiting a spherically symmetric, spinning mass can be recast as a Lense-Thirring frame-dragging effect without invoking spatial curvature. The origin of this reference frame moves around the source but the frame axes point in fixed directions. The drag can be interpreted to arise from the orbital angular momentum of the source around the origin of the reference frame. In this reference frame the effects of geodetic precession and Lense-Thirring drag due to intrinsic angular momentum of the source have the same origin, namely, gravitomagnetism
12. Technological Frame Incongruence, Diffusion, and Noncompliance
Science.gov (United States)
Sobreperez, Polly
The technological frames of reference strand of social shaping of technology theory is used to overlay the issues arising from a case study looking at noncompliance with information systems. A recent review of the theory suggests that although frame content is often addressed, frame structure, the process of framing, and the characteristics and outcomes of frames are largely overlooked. This paper attempts to address this shortfall by applying the indicators identified by case study research to the frames of different groups and using them to highlight differing perceptions and attitudes. In this way, the author suggests that issues surrounding noncompliance should not be dismissed as resistance but instead should be further studied by managers and developers, leading to accommodation of differing views. Further examination of frame incongruence reveals dependence on inefficient or ineffective organizational situations and thus these indicators can be useful in future studies to identify and address procedural, acceptance and cultural issues leading to acts of noncompliance.
13. Towards a poetics of the cinematographic frame
Directory of Open Access Journals (Sweden)
Des O'Rawe
2011-05-01
Full Text Available In delineating a poetics of the cinematographic frame, this essay presents a typology of framing styles, and demonstrates ways in which filmmakers use the frame as an expressive resource—and ways in which the frame uses them. The examples discussed are modernist in orientation, and each has a particular association with a city—its history, architecture, and cultural character. Although it is common practice to refer to various—especially, modernist—framing situations as instances of deframing, the essay also enquires into the problematic nature of this term, suggesting alternative visual and cinematographic contexts more amenable to the deconstructive implications of this term. As the boundaries between cinema and the other arts continue to converge and relations between frame, image, and screen become more complex, this essay offers a reassessment of some first principles of film language, especially the aesthetic integrity of the cinematographic frame.
14. Mapping in inertial frames
International Nuclear Information System (INIS)
Arunasalam, V.
1989-05-01
World space mapping in inertial frames is used to examine the Lorentz covariance of symmetry operations. It is found that the Galilean invariant concepts of simultaneity (S), parity (P), and time reversal symmetry (T) are not Lorentz covariant concepts for inertial observers. That is, just as the concept of simultaneity has no significance independent of the Lorentz inertial frame, likewise so are the concepts of parity and time reversal. However, the world parity (W) [i.e., the space-time reversal symmetry (P-T)] is a truly Lorentz covariant concept. Indeed, it is shown that only those mapping matrices M that commute with the Lorentz transformation matrix L (i.e., [M,L] = 0) are the ones that correspond to manifestly Lorentz covariant operations. This result is in accordance with the spirit of the world space Mach's principle. Since the Lorentz transformation is an orthogonal transformation while the Galilean transformation is not an orthogonal transformation, the formal relativistic space-time mapping theory used here does not have a corresponding non-relativistic counterpart. 12 refs
15. Supplier-induced demand as strategic framing
NARCIS (Netherlands)
De Jaegher, K.J.M.
2010-01-01
This paper develops a model of supplier-induced demand as strategic framing where the patient has reference-dependent references, and the physician can persuade the patient to buy a treatment by affecting the patient’s reference point. In the main result, the patient is assumed to have a constant
16. Prime tight frames
DEFF Research Database (Denmark)
Lemvig, Jakob; Miller, Christopher; Okoudjou, Kasso A.
2014-01-01
to suggest effective analysis and synthesis computation strategies for such frames. Finally, we describe all prime frames constructed from the spectral tetris method, and, as a byproduct, we obtain a characterization of when the spectral tetris construction works for redundancies below two.......We introduce a class of finite tight frames called prime tight frames and prove some of their elementary properties. In particular, we show that any finite tight frame can be written as a union of prime tight frames. We then characterize all prime harmonic tight frames and use thischaracterization...
17. Reynolds Stress Closure for Inertial Frames and Rotating Frames
Science.gov (United States)
Petty, Charles; Benard, Andre
2017-11-01
In a rotating frame-of-reference, the Coriolis acceleration and the mean vorticity field have a profound impact on the redistribution of kinetic energy among the three components of the fluctuating velocity. Consequently, the normalized Reynolds (NR) stress is not objective. Furthermore, because the Reynolds stress is defined as an ensemble average of a product of fluctuating velocity vector fields, its eigenvalues must be non-negative for all turbulent flows. These fundamental properties (realizability and non-objectivity) of the NR-stress cannot be compromised in computational fluid dynamic (CFD) simulations of turbulent flows in either inertial frames or in rotating frames. The recently developed universal realizable anisotropic prestress (URAPS) closure for the NR-stress depends explicitly on the local mean velocity gradient and the Coriolis operator. The URAPS-closure is a significant paradigm shift from turbulent closure models that assume that dyadic-valued operators associated with turbulent fluctuations are objective.
18. Framing Effects: Dynamics and Task Domains
Science.gov (United States)
Wang
1996-11-01
The author examines the mechanisms and dynamics of framing effects in risky choices across three distinct task domains (i.e., life-death, public property, and personal money). The choice outcomes of the problems presented in each of the three task domains had a binary structure of a sure thing vs a gamble of equal expected value; the outcomes differed in their framing conditions and the expected values, raging from 6000, 600, 60, to 6, numerically. It was hypothesized that subjects would become more risk seeking, if the sure outcome was below their aspiration level (the minimum requirement). As predicted, more subjects preferred the gamble when facing the life-death choice problems than facing the counterpart problems presented in the other two task domains. Subjects' risk preference varied categorically along the group size dimension in the life-death domain but changed more linearly over the expected value dimension in the monetary domain. Framing effects were observed in 7 of 13 pairs of problems, showing a positive frame-risk aversion and negative frame-risk seeking relationship. In addition, two types of framing effects were theoretically defined and empirically identified. A bidirectional framing effect involves a reversal in risk preference, and occurs when a decision maker's risk preference is ambiguous or weak. Four bidirectional effects were observed; in each case a majority of subjects preferred the sure outcome under a positive frame but the gamble under a negative frame. In contrast, a unidirectional framing effect refers to a preference shift due to the framing of choice outcomes: A majority of subjects preferred one choice outcome (either the sure thing or the gamble) under both framing conditions, with positive frame augmented the preference for the sure thing and negative frame augmented the preference for the gamble. These findings revealed some dynamic regularities of framing effects and posed implications for developing predictive and testable
19. Certification of caffeine reference material purity by ultraviolet/visible spectrophotometry and high-performance liquid chromatography with diode-array detection as two independent analytical methods.
Science.gov (United States)
Shehata, A B; Rizk, M S; Rend, E A
2016-10-01
Caffeine reference material certified for purity is produced worldwide, but no research work on the details of the certification process has been published in the literature. In this paper, we report the scientific details of the preparation and certification of pure caffeine reference materials. Caffeine was prepared by extraction from roasted and ground coffee by dichloromethane after heating in deionized water mixed with magnesium oxide. The extract was purified, dried, and bottled in dark glass vials. Stratified random selection was applied to select a number of vials for homogeneity and stability studies, which revealed that the prepared reference material is homogeneous and sufficiently stable. Quantification of caffeine purity % was carried out using a calibrated UV/visible spectrophotometer and a calibrated high-performance liquid chromatography with diode-array detection method. The results obtained from both methods were combined to drive the certified value and its associated uncertainty. The certified value of the reference material purity was found to be 99.86% and its associated uncertainty was ±0.65%, which makes the candidate reference material a very useful calibrant in food and drug chemical analysis. Copyright © 2016. Published by Elsevier B.V.
20. Certification of caffeine reference material purity by ultraviolet/visible spectrophotometry and high-performance liquid chromatography with diode-array detection as two independent analytical methods
Directory of Open Access Journals (Sweden)
A.B. Shehata
2016-10-01
Full Text Available Caffeine reference material certified for purity is produced worldwide, but no research work on the details of the certification process has been published in the literature. In this paper, we report the scientific details of the preparation and certification of pure caffeine reference materials. Caffeine was prepared by extraction from roasted and ground coffee by dichloromethane after heating in deionized water mixed with magnesium oxide. The extract was purified, dried, and bottled in dark glass vials. Stratified random selection was applied to select a number of vials for homogeneity and stability studies, which revealed that the prepared reference material is homogeneous and sufficiently stable. Quantification of caffeine purity % was carried out using a calibrated UV/visible spectrophotometer and a calibrated high-performance liquid chromatography with diode-array detection method. The results obtained from both methods were combined to drive the certified value and its associated uncertainty. The certified value of the reference material purity was found to be 99.86% and its associated uncertainty was ±0.65%, which makes the candidate reference material a very useful calibrant in food and drug chemical analysis.
1. Making students' frames explicit
DEFF Research Database (Denmark)
Nielsen, Louise Møller; Hansen, Poul Henrik Kyvsgaard
2016-01-01
Framing is a vital part of the design and innovation process. Frames are cognitive shortcuts (i.e. metaphors) that enable designers to connect insights about i.e. market opportunities and users needs with a set of solution principles and to test if this connection makes sense. Until now, framing...
2. The cognitive conception of human being – with reference to social rehabilitation, how to change the under age crimminal into independent person
Directory of Open Access Journals (Sweden)
Justyna Siemionow
2012-12-01
Full Text Available Social rehabilitation has been changed for many years; it has become a dynamic science. The educators are still looking for new methods and techniques. They put purposes and they are going to achieve them within individual plan of resocialization. But they are agree that the most effective way of changing the bad behavior is to change the cognitive structures. The main purpose of social rehabilitation is to make an independent person. It is necessary to help under age criminals to make their new identity. They have to participate and act in new situations which can supply them new information and knowledge.
3. Multivariate wavelet frames
CERN Document Server
2016-01-01
This book presents a systematic study of multivariate wavelet frames with matrix dilation, in particular, orthogonal and bi-orthogonal bases, which are a special case of frames. Further, it provides algorithmic methods for the construction of dual and tight wavelet frames with a desirable approximation order, namely compactly supported wavelet frames, which are commonly required by engineers. It particularly focuses on methods of constructing them. Wavelet bases and frames are actively used in numerous applications such as audio and graphic signal processing, compression and transmission of information. They are especially useful in image recovery from incomplete observed data due to the redundancy of frame systems. The construction of multivariate wavelet frames, especially bases, with desirable properties remains a challenging problem as although a general scheme of construction is well known, its practical implementation in the multidimensional setting is difficult. Another important feature of wavelet is ...
4. Supplier-induced demand as strategic framing
OpenAIRE
De Jaegher, K.J.M.
2010-01-01
This paper develops a model of supplier-induced demand as strategic framing where the patient has reference-dependent references, and the physician can persuade the patient to buy a treatment by affecting the patient’s reference point. In the main result, the patient is assumed to have a constant rate of risk aversion (lovingness) in the gain (loss) region. Two scenarios are treated. In the cure scenario, the physician wants to frame the patient’s decision problem such that he prefers to buy ...
5. Plasma physics in noninertial frames
International Nuclear Information System (INIS)
Thyagaraja, A.; McClements, K. G.
2009-01-01
Equations describing the nonrelativistic motion of a charged particle in an arbitrary noninertial reference frame are derived from the relativistically invariant form of the particle action. It is shown that the equations of motion can be written in the same form in inertial and noninertial frames, with the effective electric and magnetic fields in the latter modified by inertial effects associated with centrifugal and Coriolis accelerations. These modifications depend on the particle charge-to-mass ratio, and also the vorticity, specific kinetic energy, and compressibility of the frame flow. The Newton-Lorentz, Vlasov, and Fokker-Planck equations in such a frame are derived. Reduced models such as gyrokinetic, drift-kinetic, and fluid equations are then derivable from these equations in the appropriate limits, using standard averaging procedures. The results are applied to tokamak plasmas rotating about the machine symmetry axis with a nonrelativistic but otherwise arbitrary toroidal flow velocity. Astrophysical applications of the analysis are also possible since the power of the action principle is such that it can be used to describe relativistic flows in curved spacetime.
6. Mixed Frames and Risky Decision-Making.
Science.gov (United States)
Peng, Jiaxi; Zhang, Jiaxi; Sun, Hao; Zeng, Zhicong; Mai, Yuexia; Miao, Danmin
2017-01-01
By applying unitive vocabulary, "die" or "save," to respective frames of the Asian disease problem, Tversky and Kahneman were able to define framing effect. In this study, we preliminarily explored the effect of mixed frames, which are characterized by the use of different vocabulary in one frame. In study 1, we found that only the sure option description had significant effect on decision-making, while the effects of risky option descriptions were not significant, nor were interactions between descriptions. In study 2, the results suggested that after controlling the effects of the hedonic tone of the sure options, risky option description did not significantly predict decision-making. In study 3, we found that neither the sure-to-risky option presentation order nor presentation order within risky options had significant effect on decision-making. We thus concluded that sure option description can serve as the decision-making foundation (reference point) for decision-makers in mixed frames.
7. Time delay control of power converters: Mixed frame and stationary-frame variants
DEFF Research Database (Denmark)
Blaabjerg, Frede; Loh, P.C.; Tang, Y.
2008-01-01
In this paper, a mixed-frame and a stationary-frame time delay current controller are proposed for high precision reference tracking and disturbance rejection of power converters. In particular, the controllers use a proportional-resonant regulator in the stationary frame for regulating...... the positive and negative-sequence fundamental currents, which are known to directly influence the flow of active and reactive power in most energy conversion systems. Moreover, for the tracking or compensation of harmonics, the controllers include a time delay control path in either the synchronous...... or stationary frame, whose inherent feedback and feedforward structure can be proven to resemble a bank of resonant filters in either reference frames. Unlike other existing controllers, the proposed time delay controllers function by introducing multiple resonant peaks at only those harmonic frequencies...
8. Adenovirus E4 open reading frame 4-induced dephosphorylation inhibits E1A activation of the E2 promoter and E2F-1-mediated transactivation independently of the retinoblastoma tumor suppressor protein
DEFF Research Database (Denmark)
Mannervik, M; Fan, S; Ström, A C
1999-01-01
of the viral E4 open reading frame 4 (E4-ORF4) protein. This effect does not to require the retinoblastoma protein that previously has been shown to regulate E2F activity. The inhibitory activity of E4-ORF4 appears to be specific because E4-ORF4 had little effect on, for example, E4-ORF6/7 transactivation......Previous studies have shown that the cell cycle-regulated E2F transcription factor is subjected to both positive and negative control by phosphorylation. Here we show that in transient transfection experiments, adenovirus E1A activation of the viral E2 promoter is abrogated by coexpression...... of the E2 promoter. We further show that the repressive effect of E4-ORF4 on E2 transcription works mainly through the E2F DNA-binding sites in the E2 promoter. In agreement with this, we find that E4-ORF4 inhibits E2F-1/DP-1-mediated transactivation. We also show that E4-ORF4 inhibits E2 mRNA expression...
9. Frame on frames: an annotated bibliography
International Nuclear Information System (INIS)
Wright, T.; Tsao, H.J.
1983-01-01
The success or failure of any sample survey of a finite population is largely dependent upon the condition and adequacy of the list or frame from which the probability sample is selected. Much of the published survey sampling related work has focused on the measurement of sampling errors and, more recently, on nonsampling errors to a lesser extent. Recent studies on data quality for various types of data collection systems have revealed that the extent of the nonsampling errors far exceeds that of the sampling errors in many cases. While much of this nonsampling error, which is difficult to measure, can be attributed to poor frames, relatively little effort or theoretical work has focused on this contribution to total error. The objective of this paper is to present an annotated bibliography on frames with the hope that it will bring together, for experimenters, a number of suggestions for action when sampling from imperfect frames and that more attention will be given to this area of survey methods research
10. Modern frame structure buildings
Directory of Open Access Journals (Sweden)
В. М. Першаков
2013-07-01
Full Text Available The article deals with the design, construction and implementation of reinforced concrete frame structures with span 18, 21 m for agricultural production buildings, hall-premises of public buildings and buildings of agricultural aviation. Structures are prefabricated frame buildings and have such advantages as large space inside the structure and lower cost compared with other facilities with same purpose
11. Multimodal news framing effects
NARCIS (Netherlands)
Powell, T.E.
2017-01-01
Visuals in news media play a vital role in framing citizens’ political preferences. Yet, compared to the written word, visual images are undervalued in political communication research. Using framing theory, this thesis redresses the balance by studying the combined, or multimodal, effects of visual
12. The Frame Game
Science.gov (United States)
Edwards, Michael Todd; Cox, Dana C.
2011-01-01
In this article, the authors explore framing, a non-multiplicative technique commonly employed by students as they construct similar shapes. When students frame, they add (or subtract) a "border" of fixed width about a geometric object. Although the approach does not yield similar shapes in general, the mathematical underpinnings of…
NARCIS (Netherlands)
Jorissen, A.J.M.; Hamer, den J.; Leijten, A.J.M.; Salenikovich, A.
2014-01-01
Due to new possibilities traditional timber framing has become increasingly popular since the beginning of the 21e century. Although traditional timber framing has been used for centuries, the expected mechanical behaviour is not dealt with in great detail in building codes, guidelines or text
14. Einstein and Jordan frames reconciled: A frame-invariant approach to scalar-tensor cosmology
International Nuclear Information System (INIS)
Catena, Riccardo; Pietroni, Massimo; Scarabello, Luca
2007-01-01
Scalar-tensor theories of gravity can be formulated in different frames, most notably, the Einstein and the Jordan one. While some debate still persists in the literature on the physical status of the different frames, a frame transformation in scalar-tensor theories amounts to a local redefinition of the metric, and then should not affect physical results. We analyze the issue in a cosmological context. In particular, we define all the relevant observables (redshift, distances, cross sections, ...) in terms of frame-independent quantities. Then, we give a frame-independent formulation of the Boltzmann equation, and outline its use in relevant examples such as particle freeze-out and the evolution of the cosmic microwave background photon distribution function. Finally, we derive the gravitational equations for the frame-independent quantities at first order in perturbation theory. From a practical point of view, the present approach allows the simultaneous implementation of the good aspects of the two frames in a clear and straightforward way
15. Framing effects over time: comparing affective and cognitive news frames
NARCIS (Netherlands)
Lecheler, S.; Matthes, J.
2012-01-01
A growing number of scholars examine the duration of framing effects. However, duration is likely to differ from frame to frame, depending on how strong a frame is. This strength is likely to be enhanced by adding emotional components to a frame. By means of an experimental survey design (n = 111),
16. Framing Gangnam Style
Directory of Open Access Journals (Sweden)
Hyunsun Catherine Yoon
2017-08-01
Full Text Available This paper examines the way in which news about Gangnam Style was framed in the Korean press. First released on 15th July 2012, it became the first video to pass two billion views on YouTube. 400 news articles between July 2012 and March 2013 from two South Korean newspapers - Chosun Ilbo and Hankyoreh were analyzed using the frame analysis method in five categories: industry/economy, globalization, cultural interest, criticism, and competition. The right-left opinion cleavage is important because news frames interact with official discourses, audience frames and prior knowledge which consequently mediate effects on public opinion, policy debates, social movement and individual interpretations. Whilst the existing literature on Gangnam Style took rather holistic approach, this study aimed to fill the lacuna, considering this phenomenon as a dynamic process, by segmenting different stages - recognition, spread, peak and continuation. Both newspapers acknowledged Gangnam Style was an epochal event but their perspectives and news frames were different; globalization frame was most frequently used in Chosun Ilbo whereas cultural interest frame was most often used in Hankyoreh. Although more critical approaches were found in Hankyoreh, reflecting the right-left opinion cleavage, both papers lacked in critical appraisal and analysis of Gangnam Style’s reception in a broader context of the new Korean Wave.
17. Research on Optimization of Formula SAE Truss-Frame
Directory of Open Access Journals (Sweden)
Wang Yu
2017-01-01
Full Text Available The frame, as one of the basic components of a car, plays an important role of connecting components and withstanding various loads. The truss-frame is the commonest form of Formula SAE car in that it has many advantages, such as low cost, simple manufacture, high rigidity and high strength. The development of frame is reviewed. First, the key performance indicators and the mechanical state of the frame under different conditions are discussed. Second, a variety of optimization methods used in the design of frame are described. Finally, the test method of frame are introduced, with the experimental data and the finite element analysis of results being compared. Through analyzing and summarizing the development of the design, optimization and testing technology of the Formula SAE truss-frame, forecasting the future trends, the great theoretical reference is provided for the design and research of the follow-up frame.
18. Framing in criminal investigation
Science.gov (United States)
2016-01-01
Failures in criminal investigation may lead to wrongful convictions. Insight in the criminal investigation process is needed to understand how these investigative failures may rise and how measures can contribute to the prevention of this kind of failures. Some of the main findings of an empirical study of the criminal investigation process in four cases of major investigations are presented here. This criminal investigation process is analyzed as a process of framing, using Goffman's framing (Goffman, 1975) and interaction theories (Goffman, 1990). It shows that in addition to framing, other substantive and social factors affect the criminal investigation. PMID:29046594
19. News Media Framing of Negative Campaigning
DEFF Research Database (Denmark)
Pedersen, Rasmus Tue
2014-01-01
that news coverage of negative campaigning does apply the strategic game frame to a significantly larger degree than articles covering positive campaigning. This finding has significant implications for campaigning politicians and for scholars studying campaign and media effects.......News media coverage of election campaigns is often characterized by use of the strategic game frame and a focus on politicians’ use of negative campaigning. However, the exact relationship between these two characteristics of news coverage is largely unexplored. This article theorizes that consumer...... demand and norms of journalistic independence might induce the news media outlets to cover negative campaigning with a strategic game frame. A comprehensive content analysis based on several newspaper types, several election campaigns, and several different measurements of media framing confirms...
20. The time frame of Epstein-Barr virus latent membrane protein-1 gene to disappear in nasopharyngeal swabs after initiation of primary radiotherapy is an independently significant prognostic factor predicting local control for patients with nasopharyngeal carcinoma
International Nuclear Information System (INIS)
Lin, S.-Y.; Chang, K.-P.; Hsieh, M.-S.; Ueng, S.-H.; Hao, S.-P.; Tseng, C.-K.; Pai, P.-C.; Chang, F.-T.; Tsai, M.-H.; Tsang, N.-M.
2005-01-01
Purpose: The presence of Epstein-Barr virus latent membrane protein-1 (LMP-1) gene in nasopharyngeal swabs indicates the presence of nasopharyngeal carcinoma (NPC) mucosal tumor cells. This study was undertaken to investigate whether the time taken for LMP-1 to disappear after initiation of primary radiotherapy (RT) was inversely associated with NPC local control. Methods and Materials: During July 1999 and October 2002, there were 127 nondisseminated NPC patients receiving serial examinations of nasopharyngeal swabbing with detection of LMP-1 during the RT course. The time for LMP-1 regression was defined as the number of days after initiation of RT for LMP-1 results to turn negative. The primary outcome was local control, which was represented by freedom from local recurrence. Results: The time for LMP-1 regression showed a statistically significant influence on NPC local control both univariately (p < 0.0001) and multivariately (p = 0.004). In multivariate analysis, the administration of chemotherapy conferred a significantly more favorable local control (p = 0.03). Advanced T status (≥ T2b), overall treatment time of external photon radiotherapy longer than 55 days, and older age showed trends toward being poor prognosticators. The time for LMP-1 regression was very heterogeneous. According to the quartiles of the time for LMP-1 regression, we defined the pattern of LMP-1 regression as late regression if it required 40 days or more. Kaplan-Meier plots indicated that the patients with late regression had a significantly worse local control than those with intermediate or early regression (p 0.0129). Conclusion: Among the potential prognostic factors examined in this study, the time for LMP-1 regression was the most independently significant factor that was inversely associated with NPC local control
1. On transforms between Gabor frames and wavelet frames
DEFF Research Database (Denmark)
Christensen, Ole; Goh, Say Song
2013-01-01
We describe a procedure that enables us to construct dual pairs of wavelet frames from certain dual pairs of Gabor frames. Applying the construction to Gabor frames generated by appropriate exponential Bsplines gives wavelet frames generated by functions whose Fourier transforms are compactly...... supported splines with geometrically distributed knot sequences. There is also a reverse transform, which yields pairs of dual Gabor frames when applied to certain wavelet frames....
2. Frames of Mind in Intertemporal Choice
OpenAIRE
George F. Loewenstein
1988-01-01
Recent research has demonstrated that choices between gambles are systematically influenced by the way they are expressed. Kahneman and Tversky's Prospect Theory (Kahneman, D., A. Tversky. 1979. Prospect theory: An analysis of decision under risk. Econometrica 47(2) 363--391.) explains many of these "framing" effects as shifts in the point of reference from which prospects are evaluated. This paper demonstrates the applicability of the reference point concept to intertemporal choice. Three ex...
3. Weaving Hilbert space fusion frames
OpenAIRE
Neyshaburi, Fahimeh Arabyani; Arefijamaal, Ali Akbar
2018-01-01
A new notion in frame theory, so called weaving frames has been recently introduced to deal with some problems in signal processing and wireless sensor networks. Also, fusion frames are an important extension of frames, used in many areas especially for wireless sensor networks. In this paper, we survey the notion of weaving Hilbert space fusion frames. This concept can be had potential applications in wireless sensor networks which require distributed processing using different fusion frames...
4. Operator representations of frames
DEFF Research Database (Denmark)
Christensen, Ole; Hasannasab, Marzieh
2017-01-01
of the properties of the operator T requires more work. For example it is a delicate issue to obtain a representation with a bounded operator, and the availability of such a representation not only depends on the frame considered as a set, but also on the chosen indexing. Using results from operator theory we show......The purpose of this paper is to consider representations of frames {fk}k∈I in a Hilbert space ℋ of the form {fk}k∈I = {Tkf0}k∈I for a linear operator T; here the index set I is either ℤ or ℒ0. While a representation of this form is available under weak conditions on the frame, the analysis...... that by embedding the Hilbert space ℋ into a larger Hilbert space, we can always represent a frame via iterations of a bounded operator, composed with the orthogonal projection onto ℋ. The paper closes with a discussion of an open problem concerning representations of Gabor frames via iterations of a bounded...
5. Framing (implicitly) matters
DEFF Research Database (Denmark)
2014-01-01
Denmark is currently experiencing the highest immigration rate in its modern history. Population surveys indicate that negative public attitudes toward immigrants actually stem from attitudes toward their (perceived) Islamic affiliation. We used a framing paradigm to investigate the explicit...... and implicit attitudes of Christian and Atheist Danes toward targets framed as Muslims or as immigrants. The results showed that explicit and implicit attitudes were more negative when the target was framed as a Muslim, rather than as an immigrant. Interestingly, implicit attitudes were qualified...... by the participants’ religion. Specifically, analyses revealed that Christians demonstrated more negative implicit attitudes toward immigrants than Muslims. Conversely, Atheists demonstrated more negative implicit attitudes toward Muslims than Atheists. These results suggest a complex relationship between religion...
6. Metaphor and framing in political speeches : Effects of conceptual metaphor on recognition and recall
NARCIS (Netherlands)
Lagerwerf, L.; Yu, L.; Baicchi, Annalisa; Pinelli, Erica
2017-01-01
Cognitive linguists suggest that metaphorical framing has strong cognitive effects. However, experimental research only showed small or contradictory effects. In this chapter, an experiment is reported in which metaphor and framing were manipulated independently. Audible political speeches were
7. Video frame processor
International Nuclear Information System (INIS)
Joshi, V.M.; Agashe, Alok; Bairi, B.R.
1993-01-01
This report provides technical description regarding the Video Frame Processor (VFP) developed at Bhabha Atomic Research Centre. The instrument provides capture of video images available in CCIR format. Two memory planes each with a capacity of 512 x 512 x 8 bit data enable storage of two video image frames. The stored image can be processed on-line and on-line image subtraction can also be carried out for image comparisons. The VFP is a PC Add-on board and is I/O mapped within the host IBM PC/AT compatible computer. (author). 9 refs., 4 figs., 19 photographs
8. What's in a Frame?
DEFF Research Database (Denmark)
Holmgreen, Lise-Lotte
Maintaining a good image and reputation in the eyes of stakeholders is vital to the organisation. Thus, in its corporate communication and discourse the organisation will seek to present or frame itself as favourably as possible while observing regulations stipulating accuracy and precision...... an organisation, and hence in shaping the image projected to the public. Framing is here understood as the selection of ‘some aspects of perceived reality … [making] them more salient in the communication text, in such a way as to promote a particular problem definition, causal interpretation, moral evaluation...
9. Thinking inside the frame
DEFF Research Database (Denmark)
Knudsen, Sanne
2017-01-01
directed at the humanities. The purpose of this study is to argue the case for further research of public understanding of the humanities and to take a first step in that direction by presenting a study of the framing of the humanities in Danish print news media. Different framings of the humanities......The humanities, the natural and social sciences all represent advanced and systematic knowledge production—and they all receive public funding for doing so. However, although the field of public understanding of science has been well established for decades, similar research attention has not been...
10. Framing financial culture
DEFF Research Database (Denmark)
Just, Sine Nørholm; Mouton, Nicolaas T.O.
2014-01-01
between competing frames leads to the conclusion that this political “blame game” is related to struggles over how to define the scandal, how to conceptualize its causes, and policy recommendations. Banks may have lost the battle of “Liborgate,” but the war over the meaning of financial culture is far...... from over. Originality/value – The paper is theoretically and methodologically original in its combination of the theories of framing and stasis, and it provides analytical insights into how sense is made of financial culture in the wake of the financial crisis....
11. Timber frame walls
DEFF Research Database (Denmark)
Hansen, Ernst Jan de Place; Brandt, Erik
2010-01-01
A ventilated cavity is usually considered good practice for removing moisture behind the cladding of timber framed walls. Timber frame walls with no cavity are a logical alternative as they are slimmer and less expensive to produce and besides the risk of a two-sided fire behind the cladding....... It was found that the specific damages made to the vapour barrier as part of the test did not have any provable effect on the moisture content. In general elements with an intact vapour barrier did not show a critical moisture content at the wind barrier after four years of exposure....
12. Automatic detection of end-diastolic and end-systolic frames in 2D echocardiography.
Science.gov (United States)
Zolgharni, Massoud; Negoita, Madalina; Dhutia, Niti M; Mielewczik, Michael; Manoharan, Karikaran; Sohaib, S M Afzal; Finegold, Judith A; Sacchi, Stefania; Cole, Graham D; Francis, Darrel P
2017-07-01
Correctly selecting the end-diastolic and end-systolic frames on a 2D echocardiogram is important and challenging, for both human experts and automated algorithms. Manual selection is time-consuming and subject to uncertainty, and may affect the results obtained, especially for advanced measurements such as myocardial strain. We developed and evaluated algorithms which can automatically extract global and regional cardiac velocity, and identify end-diastolic and end-systolic frames. We acquired apical four-chamber 2D echocardiographic video recordings, each at least 10 heartbeats long, acquired twice at frame rates of 52 and 79 frames/s from 19 patients, yielding 38 recordings. Five experienced echocardiographers independently marked end-systolic and end-diastolic frames for the first 10 heartbeats of each recording. The automated algorithm also did this. Using the average of time points identified by five human operators as the reference gold standard, the individual operators had a root mean square difference from that gold standard of 46.5 ms. The algorithm had a root mean square difference from the human gold standard of 40.5 ms (P<.0001). Put another way, the algorithm-identified time point was an outlier in 122/564 heartbeats (21.6%), whereas the average human operator was an outlier in 254/564 heartbeats (45%). An automated algorithm can identify the end-systolic and end-diastolic frames with performance indistinguishable from that of human experts. This saves staff time, which could therefore be invested in assessing more beats, and reduces uncertainty about the reliability of the choice of frame. © 2017, Wiley Periodicals, Inc.
13. Frame scaling function sets and frame wavelet sets in Rd
International Nuclear Information System (INIS)
Liu Zhanwei; Hu Guoen; Wu Guochang
2009-01-01
In this paper, we classify frame wavelet sets and frame scaling function sets in higher dimensions. Firstly, we obtain a necessary condition for a set to be the frame wavelet sets. Then, we present a necessary and sufficient condition for a set to be a frame scaling function set. We give a property of frame scaling function sets, too. Some corresponding examples are given to prove our theory in each section.
14. Frames and extension problems I
DEFF Research Database (Denmark)
Christensen, Ole
2014-01-01
In this article we present a short survey of frame theory in Hilbert spaces. We discuss Gabor frames and wavelet frames and set the stage for a discussion of various extension principles; this will be presented in the article Frames and extension problems II (joint with H.O. Kim and R.Y. Kim)....
15. Promotional Frames' Influence on Price Perceptions of Two Apparel Products.
Science.gov (United States)
Stanforth, Nancy; Lennon, Sharron; Shin, Jung Im
2001-01-01
A study explored the differences in price perceptions of two apparel products when promotions were framed as either a price discount or a gift-with-purchase. The majority preferred the discount. Results illustrate the importance of promotional framing in forming consumer price perceptions. (Contains 30 references.) (Author/JOW)
16. Sparse Matrices in Frame Theory
DEFF Research Database (Denmark)
Lemvig, Jakob; Krahmer, Felix; Kutyniok, Gitta
2014-01-01
Frame theory is closely intertwined with signal processing through a canon of methodologies for the analysis of signals using (redundant) linear measurements. The canonical dual frame associated with a frame provides a means for reconstruction by a least squares approach, but other dual frames...... yield alternative reconstruction procedures. The novel paradigm of sparsity has recently entered the area of frame theory in various ways. Of those different sparsity perspectives, we will focus on the situations where frames and (not necessarily canonical) dual frames can be written as sparse matrices...
DEFF Research Database (Denmark)
Kau, Edvin
2012-01-01
Unfolding his story very gradually and arousing the viewer’s curiosity, Sitaru invites the audience to investigate the parents’ and the boy’s mutual positions in their small flat, as well as the various layers of their conversations, through such means as framing, editing style, and the use...
18. Framing the Oscars live
DEFF Research Database (Denmark)
Haastrup, Helle Kannik
2016-01-01
How is the global media event of the Oscars localised through the talk show on Danish television? How are both the mediated film star and the special brand of Hollywood celebrity culture addressed by the cultural intermediaries in the Danish framing? These are the questions I propose to answer...
19. Framing ‘fracking’
NARCIS (Netherlands)
Williams, Laurence; Macnaghten, Philip; Davies, Richard; Curtis, Sarah
2017-01-01
The prospect of fracking in the United Kingdom has been accompanied by significant public unease. We outline how the policy debate is being framed by UK institutional actors, finding evidence of a dominant discourse in which the policy approach is defined through a deficit model of public
National Research Council Canada - National Science Library
Saywell, John; Anastakis, Dimitry; Bryden, Penny E
2009-01-01
... the pervasive effects that federalism has on Canadian politics, economics, culture, and history, and provide a detailed framework in which to understand contemporary federalism. Written in honour of John T. Saywell's half-century of accomplished and influential scholarly work and teaching, Framing Canadian Federalism is a timely and fitting t...
1. Institutional Justification in Frames
DEFF Research Database (Denmark)
consensus. It extents research on framing in mass communication by applying institutional theory and Boltanski and Thévenot’s (2006) theory on justification in order to explain how the success and failure of proposed interpretations depend on the mobilization of accepted social institutions to justify...
2. Banach frames for multivariate alpha-modulation spaces
DEFF Research Database (Denmark)
Borup, Lasse; Nielsen, Morten
2006-01-01
The α-modulation spaces [$Mathematical Term$], form a family of spaces that include the Besov and modulation spaces as special cases. This paper is concerned with construction of Banach frames for α-modulation spaces in the multivariate setting. The frames constructed are unions of independent Ri...... Riesz sequences based on tensor products of univariate brushlet functions, which simplifies the analysis of the full frame. We show that the multivariate α-modulation spaces can be completely characterized by the Banach frames constructed....
3. Are Independent Probes Truly Independent?
Science.gov (United States)
Camp, Gino; Pecher, Diane; Schmidt, Henk G.; Zeelenberg, Rene
2009-01-01
The independent cue technique has been developed to test traditional interference theories against inhibition theories of forgetting. In the present study, the authors tested the critical criterion for the independence of independent cues: Studied cues not presented during test (and unrelated to test cues) should not contribute to the retrieval…
4. Some relationship between G-frames and frames
Directory of Open Access Journals (Sweden)
Mehdi Rashidi-Kouchi
2015-06-01
Full Text Available In this paper we proved that every g-Riesz basis for Hilbert space $H$ with respect to $K$ by adding a condition is a Riesz basis for Hilbert $B(K$-module $B(H,K$. This is an extension of [A. Askarizadeh,M. A. Dehghan, {em G-frames as special frames}, Turk. J. Math., 35, (2011 1-11]. Also, we derived similar results for g-orthonormal and orthogonal bases. Some relationships between dual frame, dual g-frame and exact frame and exact g-frame are presented too.
5. Solid-state framing camera with multiple time frames
Energy Technology Data Exchange (ETDEWEB)
Baker, K. L.; Stewart, R. E.; Steele, P. T.; Vernon, S. P.; Hsing, W. W.; Remington, B. A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)
2013-10-07
A high speed solid-state framing camera has been developed which can operate over a wide range of photon energies. This camera measures the two-dimensional spatial profile of the flux incident on a cadmium selenide semiconductor at multiple times. This multi-frame camera has been tested at 3.1 eV and 4.5 keV. The framing camera currently records two frames with a temporal separation between the frames of 5 ps but this separation can be varied between hundreds of femtoseconds up to nanoseconds and the number of frames can be increased by angularly multiplexing the probe beam onto the cadmium selenide semiconductor.
6. Wavelet frames and their duals
DEFF Research Database (Denmark)
Lemvig, Jakob
2008-01-01
frames with good time localization and other attractive properties. Furthermore, the dual wavelet frames are constructed in such a way that we are guaranteed that both frames will have the same desirable features. The construction procedure works for any real, expansive dilation. A quasi-affine system....... The signals are then represented by linear combinations of the building blocks with coefficients found by an associated frame, called a dual frame. A wavelet frame is a frame where the building blocks are stretched (dilated) and translated versions of a single function; such a frame is said to have wavelet...... structure. The dilation of the wavelet building blocks in higher dimension is done via a square matrix which is usually taken to be integer valued. In this thesis we step away from the "usual" integer, expansive dilation and consider more general, expansive dilations. In most applications of wavelet frames...
7. FishFrame
DEFF Research Database (Denmark)
Degel, Henrik; Jansen, Teunis
2006-01-01
. Development and test of software modules can be done once and reused by all. The biggest challenge in this is not technical – it is in organisation, coordination and trust. This challenge has been addressed by FishFrame - a web-based datawarehouse application. The “bottom-up” approach with maximum involvement...... of end users from as many labs and user groups as possible has been rather slow but quite successful in building international trust and cooperation around the system. This is mandatory prerequisites when our primary goal is not the programming project itself, but the creation of a tool that adds real...... value to users and in the end improves the way we work with our data. FishFrame version 4.2 is presented and the lessons learned from the process are discussed....
8. Framing Light Rail Projects
DEFF Research Database (Denmark)
Olesen, Mette
2014-01-01
In Europe, there has been a strong political will to implement light rail. This article contributes to the knowledge concerning policies around light rail by analysing how local actors frame light rail projects and which rationalities and arguments are present in this decision-making process....... The article draws on the socio-technical approach to mobilities studies in order to reassemble the decision-making process in three European cases: Bergen, Angers, and Bern. This article provides insights into the political, discursive and material production of light rail mobilities in a European context....... It identifies the planning rationales behind the systems and the policies that have been supportive of this light rail vision. Finally, the article identifies the practical challenges and potentials that have been connected to the different local frames of light rail mobility which can be used in future...
9. Framing a Bank
DEFF Research Database (Denmark)
Holmgreen, Lise-Lotte
2012-01-01
Danish bank, Danske Bank, during the 2008 financial crisis and hence in shaping its image projected to the public. Through the study of a number of semantic frames adopted by the Danish print press and those adopted by the Bank, this article will argue for the constructions of the press putting...... considerable strain on the Bank and its image, leading it to reconsider its previous strategy of denial of responsibility...
10. Optical loop framing
International Nuclear Information System (INIS)
Kalibjian, R.; Chong, Y.P.; Prono, D.S.; Cavagnolo, H.R.
1984-06-01
The ATA provides an electron beam pulse of 70-ns duration at a 1-Hz rate. Our present optical diagnostics technique involve the imaging of the visible light generated by the beam incident onto the plant of a thin sheet of material. It has already been demonstrated that the light generated has a sufficiently fast temporal reponse in performing beam diagnostics. Notwithstanding possible beam emittance degradation due to scattering in the thin sheet, the observation of beam spatial profiles with relatively high efficiencies has provided data complementary to that obtained from beam wall current monitors and from various x-ray probes and other electrical probes. The optical image sensor consists of a gated, intensified television system. The gate pulse of the image intensifier can be appropriately delayed to give frames that are time-positioned from the head to the tail of the beam with a minimum gate time of 5-ns. The spatial correlation of the time frames from pulse to pulse is very good for a stable electron beam; however, when instabilities do occur, it is difficult to properly assess the spatial composition of the head and the tail of the beam on a pulse-to-pulse basis. Multiple gating within a pulse duration becomes desirable but cannot be performed because the recycle time (20-ms) of the TV system is much longer than the beam pulse. For this reason we have developed an optical-loop framing technique that will allow the recording of two frames within one pulse duration with our present gated/intensified TV system
11. Density of Gabor Frames
DEFF Research Database (Denmark)
Christensen, Ole; Heil, C.; Deng, B.
1997-01-01
A Gabor system is a set of time-frequency shifts$S(g,\\Lambda) = \\{e^{2\\pi i b x} g(x-a)\\}_{(a,b) \\in \\Lambda}$of a function $g \\in L^2({\\bold R}^d)$.We prove that if a finite union of Gabor systems$\\bigcup_{k=1}^r S(g_k,\\Lambda_k)$, with arbitrary sequences $\\Lambda_k$,forms a frame for L^2({\\bo... 12. Development of a slim window frame made of glass fibre reinforced polyester DEFF Research Database (Denmark) Appelfeld, David; Hansen, Christian Skodborg; Svendsen, Svend 2010-01-01 This paper presents the development of an energy efficient window frame made of a glass fibre reinforced polyester (GFRP) material. Three frame proposals were considered. The energy and structural performances of the frames were calculated and compared with wooden and aluminium reference frames....... In order to estimate performances, detailed thermal calculations were performed in four successive steps including solar energy and light transmittance in addition to heat loss and supplemented with a simplified structural calculation of frame load capacity and deflection. Based on these calculations, we...... carried out an analysis of the potential energy savings of the frame. The calculations for a reference office building showed that the heating demand was considerably lower with a window made of GFRP than with the reference frames. It was found that GFRP is suitable for window frames, and windows made... 13. Framing Vision: An Examination of Framing, Sensegiving, and Sensemaking during a Change Initiative Science.gov (United States) Hamilton, William 2016-01-01 The purpose of this short article is to review the findings from an instrumental case study that examines how a college president used what this article refers to as "frame alignment processes" to mobilize internal and external support for a college initiative--one that achieved success under the current president. Specifically, I… 14. Concepts and Contexts – Argumentative Forms of Framing DEFF Research Database (Denmark) Gabrielsen, Jonas; Nørholm Just, Sine; Bengtsson, Mette 2011-01-01 this argument we combine theories of framing with the classical rhetorical theory of the stases, more precisely status definitio and status translatio. Our focus is primarily theoretical, but we illustrate our points by means of examples taken from public debates on the value of real estate.......The notion of framing has become central in the field of argumentation. The question is, however, what we gain from studying the process of argumentation through framing, since framing is itself a broad concept in need of specification. Different traditions understand the term differently......, and it is necessary to determine what argumentative forms the concept of framing actually covers. In this paper we argue that framing refers to at least two different argumentative forms. One is an internal definition of the concepts in question; the other is an external shift in the context of the case. In making... 15. Attribute Framing and Goal Framing Effects in Health Decisions. Science.gov (United States) Krishnamurthy, Parthasarathy; Carter, Patrick; Blair, Edward 2001-07-01 Levin, Schneider, and Gaeth (LSG, 1998) have distinguished among three types of framing-risky choice, attribute, and goal framing-to reconcile conflicting findings in the literature. In the research reported here, we focus on attribute and goal framing. LSG propose that positive frames should be more effective than negative frames in the context of attribute framing, and negative frames should be more effective than positive frames in the context of goal framing. We test this framework by manipulating frame valence (positive vs negative) and frame type (attribute vs goal) in a unified context with common procedures. We also argue that the nature of effects in a goal-framing context may depend on the extent to which the research topic has "intrinsic self-relevance" to the population. In the context of medical decision making, we operationalize low intrinsic self-relevance by using student subjects and high intrinsic self-relevance by using patients. As expected, we find complete support for the LSG framework under low intrinsic self-relevance and modified support for the LSG framework under high intrinsic self-relevance. Overall, our research appears to confirm and extend the LSG framework. Copyright 2001 Academic Press. 16. Conformal frame dependence of inflation International Nuclear Information System (INIS) Domènech, Guillem; Sasaki, Misao 2015-01-01 Physical equivalence between different conformal frames in scalar-tensor theory of gravity is a known fact. However, assuming that matter minimally couples to the metric of a particular frame, which we call the matter Jordan frame, the matter point of view of the universe may vary from frame to frame. Thus, there is a clear distinction between gravitational sector (curvature and scalar field) and matter sector. In this paper, focusing on a simple power-law inflation model in the Einstein frame, two examples are considered; a super-inflationary and a bouncing universe Jordan frames. Then we consider a spectator curvaton minimally coupled to a Jordan frame, and compute its contribution to the curvature perturbation power spectrum. In these specific examples, we find a blue tilt at short scales for the super-inflationary case, and a blue tilt at large scales for the bouncing case 17. MedlinePlus FAQ: Framing Science.gov (United States) ... URL of this page: https://medlineplus.gov/faq/framing.html I'd like to link to MedlinePlus, ... M. encyclopedia. Our license agreements do not permit framing of their content from our site. For more ... 18. Conformal frame dependence of inflation Energy Technology Data Exchange (ETDEWEB) Domènech, Guillem; Sasaki, Misao, E-mail: guillem.domenech@yukawa.kyoto-u.ac.jp, E-mail: misao@yukawa.kyoto-u.ac.jp [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan) 2015-04-01 Physical equivalence between different conformal frames in scalar-tensor theory of gravity is a known fact. However, assuming that matter minimally couples to the metric of a particular frame, which we call the matter Jordan frame, the matter point of view of the universe may vary from frame to frame. Thus, there is a clear distinction between gravitational sector (curvature and scalar field) and matter sector. In this paper, focusing on a simple power-law inflation model in the Einstein frame, two examples are considered; a super-inflationary and a bouncing universe Jordan frames. Then we consider a spectator curvaton minimally coupled to a Jordan frame, and compute its contribution to the curvature perturbation power spectrum. In these specific examples, we find a blue tilt at short scales for the super-inflationary case, and a blue tilt at large scales for the bouncing case. 19. Brain potentials associated with the outcome processing in framing effects. Science.gov (United States) Ma, Qingguo; Feng, Yandong; Xu, Qing; Bian, Jun; Tang, Huixian 2012-10-24 Framing effect is a cognitive bias referring to the phenomenon that people respond differently to different but objectively equivalent descriptions of the same problem. By measuring event-related potentials, the present study aimed to investigate the neural mechanisms underlying the framing effect, especially how the negative and positive frames influence the outcome processing in our brain. Participants were presented directly with outcomes framed either positively in terms of lives saved or negatively in terms of lives lost in large and small group conditions, and were asked to rate the favorableness of each of them. The behavioral results showed that the framing effect occurred in both group size conditions, with more favorable evaluations associated with positive framing. Compared with outcomes in positive framing condition, a significant feedback-related negativity (FRN) effect was elicited by outcomes in negative framing condition, even though the outcomes in different conditions were objectively equivalent. The results are explained in terms of the associative model of attribute framing effect which states that attribute framing effect occurs as a result of a valence-based associative processing. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved. 20. Frames in super Hilbert modules Directory of Open Access Journals (Sweden) Mehdi Rashidi-Kouchi 2018-01-01 Full Text Available In this paper, we define super Hilbert module and investigate frames in this space. Super Hilbert modules are generalization of super Hilbert spaces in Hilbert C*-module setting. Also, we define frames in a super Hilbert module and characterize them by using of the concept of g-frames in a Hilbert C*-module. Finally, disjoint frames in Hilbert C*-modules are introduced and investigated. 1. New avenues for framing research NARCIS (Netherlands) de Vreese, C.H. 2012-01-01 In this article, the author reviews the studies in this special issue of the American Behavioral Scientist. It is a strong collection of articles reporting findings from an integrated project that looks at frame building, frames, and effects of frames. The project is part of an exciting large-scale 2. VIOLENT FRAMES IN ACTION Energy Technology Data Exchange (ETDEWEB) Sanfilippo, Antonio P.; McGrath, Liam R.; Whitney, Paul D. 2011-11-17 We present a computational approach to radical rhetoric that leverages the co-expression of rhetoric and action features in discourse to identify violent intent. The approach combines text mining and machine learning techniques with insights from Frame Analysis and theories that explain the emergence of violence in terms of moral disengagement, the violation of sacred values and social isolation in order to build computational models that identify messages from terrorist sources and estimate their proximity to an attack. We discuss a specific application of this approach to a body of documents from and about radical and terrorist groups in the Middle East and present the results achieved. 3. Continuous Shearlet Tight Frames KAUST Repository Grohs, Philipp 2010-10-22 Based on the shearlet transform we present a general construction of continuous tight frames for L2(ℝ2) from any sufficiently smooth function with anisotropic moments. This includes for example compactly supported systems, piecewise polynomial systems, or both. From our earlier results in Grohs (Technical report, KAUST, 2009) it follows that these systems enjoy the same desirable approximation properties for directional data as the previous bandlimited and very specific constructions due to Kutyniok and Labate (Trans. Am. Math. Soc. 361:2719-2754, 2009). We also show that the representation formulas we derive are in a sense optimal for the shearlet transform. © 2010 Springer Science+Business Media, LLC. 4. Hybrid Synchronous/Stationary Reference Frame Filtering based PLL DEFF Research Database (Denmark) Golestan, Saeed; Guerrero, Josep M.; Abusorrah, Abdullah 2015-01-01 Designing an effective phase-locked loop (PLL) for three-phase applications is the objective of this paper. The designed PLL structure is able to provide an accurate estimation of grid voltage frequency and phase even in the presence of all harmonic components of both positive and negative... 5. Motor Extinction in Distinct Reference Frames: A Double Dissociation Directory of Open Access Journals (Sweden) Jennifer Heidler-Gary 2013-01-01 Full Text Available Objective: Test the hypothesis that right hemisphere stroke can cause extinction of left hand movements or movements of either hand held in left space, when both are used simultaneously, possibly depending on lesion site. 6. Childhood PTSD in Israel: A Cross Cultural Frame of Reference. Science.gov (United States) Milgram, Noach Norman There is considerable awareness among Israeli mental health workers and citizens of the importance of differentiating between acute or chronic reactions to severely stressful life situations and manifestations of mental illness and anxiety, or developmental and adjustment disorders. Israeli mental health workers have become expert and are heavily… 7. Frame of Reference: Open Access Starts with You Science.gov (United States) Goetsch, Lori A. 2010-01-01 Federal legislation now requires the deposit of some taxpayer-funded research in "open-access" repositories--that is, sites where scholarship and research are made freely available over the Internet. The institutions whose faculty produce the research have begun to see the benefit of open-access publication as well. From the perspective of faculty… 8. Frames of Reference in Mobile Augmented Reality Displays Science.gov (United States) Mou, Weimin; Biocca, Frank; Owen, Charles B.; Tang, Arthur; Xiao, Fan; Lim, Lynette 2004-01-01 In 3 experiments, the authors investigated spatial updating in augmented reality environments. Participants learned locations of virtual objects on the physical floor. They were turned to appropriate facing directions while blindfolded before making pointing judgments (e.g., "Imagine you are facing X. Point to Y"). Experiments manipulated the… 9. Model-Independent Diffs DEFF Research Database (Denmark) Könemann, Patrick just contain a list of strings, one for each line, whereas the structure of models is defined by their meta models. There are tools available which are able to compute the diff between two models, e.g. RSA or EMF Compare. However, their diff is not model-independent, i.e. it refers to the models... 10. on Goal Framing Directory of Open Access Journals (Sweden) Eulàlia P. Abril 2014-01-01 Full Text Available En respuesta a la enorme y algunas veces conceptualmente inconsistente literatura sobre valence framing,Levin y sus colegas (1998 desarrollaron una tipología de encuadre de valencia que organiza los diferentesresultados a partir de elección arriesgada, atributo, y encuadre de los resultados (goal framing. Este estudiofavorece la literatura sobre encuadre de los resultados mediante (a su aplicación en el contexto de una cuestiónsocial como la pobreza infantil extrema; y (b el examen de los mecanismos afectivos sobre el cual el encuadrede los resultados es de eficacia persuasiva. Los resultados experimentales (N = 197 mostraron que la exposiciónal mensaje de encuadre de pérdida permitió un apoyo mayor hacia las políticas públicas que buscan erradicar lapobreza infantil, en comparación con el mensaje de encuadre de ganancia. Los resultados también revelaronque el afecto negativo sirve como herramienta mediadora de apoyo hacia las políticas públicas. Estos hallazgossugieren que, en el contexto del apoyo social hacia la población pobre, la capacidad de persuasión dentro delencuadre de pérdida se facilita cuando los participantes experimentan afectos negativos. 11. Cognitive framing in action. Science.gov (United States) Huhn, John M; Potts, Cory Adam; Rosenbaum, David A 2016-06-01 Cognitive framing effects have been widely reported in higher-level decision-making and have been ascribed to rules of thumb for quick thinking. No such demonstrations have been reported for physical action, as far as we know, but they would be expected if cognition for physical action is fundamentally similar to cognition for higher-level decision-making. To test for such effects, we asked participants to reach for a horizontally-oriented pipe to move it from one height to another while turning the pipe 180° to bring one end (the "business end") to a target on the left or right. From a physical perspective, participants could have always rotated the pipe in the same angular direction no matter which end was the business end; a given participant could have always turned the pipe clockwise or counter-clockwise. Instead, our participants turned the business end counter-clockwise for left targets and clockwise for right targets. Thus, the way the identical physical task was framed altered the way it was performed. This finding is consistent with the hypothesis that cognition for physical action is fundamentally similar to cognition for higher-level decision-making. A tantalizing possibility is that higher-level decision heuristics have roots in the control of physical action, a hypothesis that accords with embodied views of cognition. Copyright © 2016 Elsevier B.V. All rights reserved. 12. Identifying issue frames in text. Directory of Open Access Journals (Sweden) Eyal Sagi Full Text Available Framing, the effect of context on cognitive processes, is a prominent topic of research in psychology and public opinion research. Research on framing has traditionally relied on controlled experiments and manually annotated document collections. In this paper we present a method that allows for quantifying the relative strengths of competing linguistic frames based on corpus analysis. This method requires little human intervention and can therefore be efficiently applied to large bodies of text. We demonstrate its effectiveness by tracking changes in the framing of terror over time and comparing the framing of abortion by Democrats and Republicans in the U.S. 13. Automatic frame-centered object representation and integration revealed by iconic memory, visual priming, and backward masking. Science.gov (United States) Lin, Zhicheng; He, Sheng 2012-10-25 Object identities ("what") and their spatial locations ("where") are processed in distinct pathways in the visual system, raising the question of how the what and where information is integrated. Because of object motions and eye movements, the retina-based representations are unstable, necessitating nonretinotopic representation and integration. A potential mechanism is to code and update objects according to their reference frames (i.e., frame-centered representation and integration). To isolate frame-centered processes, in a frame-to-frame apparent motion configuration, we (a) presented two preceding or trailing objects on the same frame, equidistant from the target on the other frame, to control for object-based (frame-based) effect and space-based effect, and (b) manipulated the target's relative location within its frame to probe frame-centered effect. We show that iconic memory, visual priming, and backward masking depend on objects' relative frame locations, orthogonal of the retinotopic coordinate. These findings not only reveal that iconic memory, visual priming, and backward masking can be nonretinotopic but also demonstrate that these processes are automatically constrained by contextual frames through a frame-centered mechanism. Thus, object representation is robustly and automatically coupled to its reference frame and continuously being updated through a frame-centered, location-specific mechanism. These findings lead to an object cabinet framework, in which objects ("files") within the reference frame ("cabinet") are orderly coded relative to the frame. 14. Versions and perversions of rigid frames: The bucking importance in the beams design of industrial warehouses International Nuclear Information System (INIS) Guerra Romero, I.; Fernandez Majo, M. C.; Valdes, A. J. 2010-01-01 In this paper many bibliographic references have been analyses which deal on the importance of the buckling in rigid frames, and many versions of it, have been got. About 70 frames have been analysed by the authors and they have found that it is advisable to consider the bucking in the design of frames beams. (Author) 30 refs. 15. Message framing and perinatal decisions. Science.gov (United States) Haward, Marlyse F; Murphy, Ryan O; Lorenz, John M 2008-07-01 The purpose of this study was to explore the effect of information framing on parental decisions about resuscitation of extremely premature infants. Secondary outcomes focused on elucidating the impact of other variables on treatment choices and determining whether those effects would take precedence over any framing effects. This confidential survey study was administered to adult volunteers via the Internet. The surveys depicted a hypothetical vignette of a threatened delivery at gestational age of 23 weeks, with prognostic outcome information framed as either survival with lack of disability (positive frame) or chance of dying and likelihood of disability among survivors (negative frame). Participants were randomly assigned to receive either the positively or negatively framed vignette. They were then asked to choose whether they would prefer resuscitation or comfort care. After completing the survey vignette, participants were directed to a questionnaire designed to test the secondary hypothesis and to explore possible factors associated with treatment decisions. A total of 146 subjects received prognostic information framed as survival data and 146 subjects received prognostic information framed as mortality data. Overall, 24% of the sample population chose comfort care and 76% chose resuscitation. A strong trend was detected toward a framing effect on treatment preference; respondents for whom prognosis was framed as survival data were more likely to elect resuscitation. This framing effect was significant in a multivariate analysis controlling for religiousness, parental status, and beliefs regarding the sanctity of life. Of these covariates, only religiousness modified susceptibility to framing; participants who were not highly religious were significantly more likely to be influenced to opt for resuscitation by the positive frame than were participants who were highly religious. Framing bias may compromise efforts to approach prenatal counseling in a 16. Motor coordination uses external spatial coordinates independent of developmental vision. Science.gov (United States) Heed, Tobias; Röder, Brigitte 2014-07-01 The constraints that guide bimanual movement coordination are informative about the processing principles underlying movement planning in humans. For example, symmetry relative to the body midline benefits finger and hand movements independent of hand posture. This symmetry constraint has been interpreted to indicate that movement coordination is guided by a perceptual code. Although it has been assumed implicitly that the perceptual system at the heart of this constraint is vision, this relationship has not been tested. Here, congenitally blind and sighted participants made symmetrical and non-symmetrical (that is, parallel) bimanual tapping and finger oscillation movements. For both groups, symmetrical movements were executed more correctly than parallel movements, independent of anatomical constraints like finger homology and hand posture. For the blind, the reliance on external spatial factors in movement coordination stands in stark contrast to their use of an anatomical reference frame in perceptual processing. Thus, the externally coded symmetry constraint evident in bimanual coordination can develop in the absence of the visual system, suggesting that the visual system is not critical for the establishment of an external-spatial reference frame in movement coordination. Copyright © 2014 Elsevier B.V. All rights reserved. 17. Framing the Manager DEFF Research Database (Denmark) Holmgreen, Lise-Lotte 2013-01-01 Genres are ways for organisations of discursively interacting with the surrounding world, with the aim of achieving specific disciplinary goals (Bhatia 2004). As such, the management job ad has the objective of finding the right candidate for the management job advertised (Norlyk 2006......). In this process, framing (Evans & Green 2006; Fillmore 1982; Kövecses 2006; Lakoff 1987, 1996) plays a salient role in conceptualising the profile and qualities of the preferred candidate, drawing on established cultural models of what constitutes the perfect leader. Thus, in a Danish setting we may talk of two...... in this realisation, the fact that one of the two models, the ‘goal-oriented motivator’ model, seems to be monopolising the genre raises a number of issues that need to be addressed: How is this model realised conceptually and linguistically? Why does this model continue to be the Danish business world’s preferred... 18. Shield support frame. Schildausbaugestell Energy Technology Data Exchange (ETDEWEB) Plaga, K. 1981-09-17 A powered shield support frame for coal sheds is described comprising of two bottom sliding shoes, a large area gob shield and a larg area roof assembly, all joined movable together. The sliding shoes and the gob shield are joined by a lemniscate guide. Two hydraulic props are arranged at the face-side at one third of the length of the sliding shoes and at the goaf-side at one third of the length of the roof assembly. A nearly horizontal lying pushing prop unit joins the bottom wall sliding shoes to the goaf-side lemniscate guide. This assembly can be applied to seams with a thickness down to 45 cm. (OGR). 19. Voz sobre frame relay OpenAIRE D´Elia, Gabriel Anibal 2000-01-01 Esta tesis trata el tema de VOFR, desde la digitalización de la voz hasta su transmisión a través de dicha red, así también como la comparación con otros medios de transporte como VOIP. Dada las características del protocolo frame relay y su disponibilidad se eligió como el medio más apropiado para la transmisión de voz y datos en forma integrada sobre una misma red. El trabajo comienza con una breve explicación de la voz, su digitalización y forma actual de transmisión a través de una red di... 20. Riesz frames and approximation of the frame coefficients DEFF Research Database (Denmark) Casazza, P.; Christensen, Ole 1998-01-01 A frame is a fmaily {f i } i=1 ∞ of elements in a Hilbert space with the property that every element in can be written as a (infinite) linear combination of the frame elements. Frame theory describes how one can choose the corresponding coefficients, which are called frame coefficients. From...... the mathematical point of view this is gratifying, but for applications it is a problem that the calculation requires inversion of an operator on . The projection method is introduced in order to avoid this problem. The basic idea is to consider finite subfamilies {f i } i=1 n of the frame and the orthogonal...... projection Pn onto its span. For has a representation as a linear combination of fi, i=1,2,..., n and the corresponding coefficients can be calculated using finite dimensional methods. We find conditions implying that those coefficients converge to the correct frame coefficients as n→∞, in which case we have... 1. Behaviour of Strengthened RC Frames with Eccentric Steel Braced Frames Directory of Open Access Journals (Sweden) Kamanli Mehmet 2017-01-01 Full Text Available After devastating earthquakes in recent years, strengthening of reinforced concrete buildings became an important research topic. Reinforced concrete buildings can be strengthened by steel braced frames. These steel braced frames may be made of concentrically or eccentrically indicated in Turkish Earthquake Code 2007. In this study pushover analysis of the 1/3 scaled 1 reinforced concrete frame and 1/3 scaled 4 strengthened reinforced concrete frames with internal eccentric steel braced frames were conducted by SAP2000 program. According to the results of the analyses conducted, load-displacement curves of the specimens were compared and evaluated. Adding eccentric steel braces to the bare frame decreased the story drift, and significantly increased strength, stiffness and energy dissipation capacity. In this strengthening method lateral load carrying capacity, stiffness and dissipated energy of the structure can be increased. 2. Behaviour of Strengthened RC Frames with Eccentric Steel Braced Frames Science.gov (United States) Kamanli, Mehmet; Unal, Alptug 2017-10-01 After devastating earthquakes in recent years, strengthening of reinforced concrete buildings became an important research topic. Reinforced concrete buildings can be strengthened by steel braced frames. These steel braced frames may be made of concentrically or eccentrically indicated in Turkish Earthquake Code 2007. In this study pushover analysis of the 1/3 scaled 1 reinforced concrete frame and 1/3 scaled 4 strengthened reinforced concrete frames with internal eccentric steel braced frames were conducted by SAP2000 program. According to the results of the analyses conducted, load-displacement curves of the specimens were compared and evaluated. Adding eccentric steel braces to the bare frame decreased the story drift, and significantly increased strength, stiffness and energy dissipation capacity. In this strengthening method lateral load carrying capacity, stiffness and dissipated energy of the structure can be increased. 3. The covariance of GPS coordinates and frames International Nuclear Information System (INIS) Lachieze-Rey, Marc 2006-01-01 We explore, in the general relativistic context, the properties of the recently introduced global positioning system (GPS) coordinates, as well as those of the associated frames and coframes that they define. We show that they are covariant and completely independent of any observer. We show that standard spectroscopic and astrometric observations allow any observer to measure (i) the values of the GPS coordinates at his position (ii) the components of his 4-velocity and (iii) the components of the metric in the GPS frame. This provides this system with a unique value both for conceptual discussion (no frame dependence) and for practical use (involved quantities are directly measurable): localization, motion monitoring, astrometry, cosmography and tests of gravitation theories. We show explicitly, in the general relativistic context, how an observer may estimate his position and motion, and reconstruct the components of the metric. This arises from two main results: the extension of the velocity fields of the probes to the whole (curved) spacetime, and the identification of the components of the observer's velocity in the GPS frame with the (inversed) observed redshifts of the probes. Specific cases (non-relativistic velocities, Minkowski and Friedmann-Lemaitre spacetimes, geodesic motions) are studied in detail 4. Framing effects in choices between multioutcome life-expectancy lotteries. Science.gov (United States) Bernstein, L M; Chapman, G B; Elstein, A S 1999-01-01 To explore framing or editing effects and a method to debias framing in a clinical context. Clinical scenarios using multioutcome life-expectancy lotteries of equal value required choices between two supplementary drugs that either prolonged or shortened life from the 20-year beneficial effect of a baseline drug. The effects of these supplementary drugs were presented in two conditions, using a between-subjects design. In segregated editing (n = 116) the effects were presented separately from the effects of the baseline drug. In integrated editing (n = 100), effects of supplementary and baseline drugs were combined in the lottery presentation. Each subject responded to 30 problems. To explore one method of debiasing, another 100 subjects made choices after viewing both segregated and integrated editings of 20 problems (dual framing). Statistically significant preference reversals between segregated and integrated editing of pure lotteries occurred only when one framing placed outcomes in the gain domain, and the other framing placed them in the loss domain. When both editings resulted in gain-domain outcomes only, there was no framing effect. There was a related relationship of framing-effect shifts from losses to gains in mixed-lottery-choice problems. Responses to the dual framing condition did not consistently coincide with responses to either single framing. In some situations, dual framing eliminated or lessened framing effects. The results support two components of prospect theory, coding outcomes as gains or losses from a reference point, and an s-shaped utility function (concave in gain, convex in loss domains). Presenting both alternative editings of a complex situation prior to choice more fully informs the decision maker and may help to reduce framing effects. Given the extent to which preferences shift in response to alternative presentations, it is unclear which choice represents the subject's "true preferences." 5. Six problems in frame theory DEFF Research Database (Denmark) Christensen, Ole 2014-01-01 We discuss various problems in frame theory that have been open for some years. A short discussion of frame theory is also provided, but it only contains the information that is necessary in order to understand the open problems and their role.......We discuss various problems in frame theory that have been open for some years. A short discussion of frame theory is also provided, but it only contains the information that is necessary in order to understand the open problems and their role.... 6. Pairs of dual periodic frames DEFF Research Database (Denmark) Christensen, Ole; Goh, Say Song 2012-01-01 The time–frequency analysis of a signal is often performed via a series expansion arising from well-localized building blocks. Typically, the building blocks are based on frames having either Gabor or wavelet structure. In order to calculate the coefficients in the series expansion, a dual frame...... is needed. The purpose of the present paper is to provide constructions of dual pairs of frames in the setting of the Hilbert space of periodic functions L2(0,2π). The frames constructed are given explicitly as trigonometric polynomials, which allows for an efficient calculation of the coefficients... 7. Frames, agency and institutional change DEFF Research Database (Denmark) Rasmussen, Grane Mikael Gregaard; Jensen, Per Langaa; Gottlieb, Stefan Christoffer 2017-01-01 This study examines change and the sources influencing the formulation and diffusion of policies in construction. The change examined is the introduction of a benchmarking policy initiative in the Danish construction industry. Using institutional theory with emphasis on the concepts of frames...... and framings, we show how strategically motivated actors are able to frame policy problems in ways that disclose the mixture of motives, interests and institutional mechanisms at play in change processes. In doing so, we contribute to the literature on the role of agency in institutional change and the framing... 8. Independent preferences DEFF Research Database (Denmark) Vind, Karl 1991-01-01 A simple mathematical result characterizing a subset of a product set is proved and used to obtain additive representations of preferences. The additivity consequences of independence assumptions are obtained for preferences which are not total or transitive. This means that most of the economic ...... theory based on additive preferences - expected utility, discounted utility - has been generalized to preferences which are not total or transitive. Other economic applications of the theorem are given... 9. Mixed-frame and stationary-frame repetitive control schemes for compensating typical load and grid harmonics DEFF Research Database (Denmark) Loh, P.; Tang, Y.; Blaabjerg, Frede 2011-01-01 In this study, repetitive current controllers operating in either the mixed or stationary frame are proposed for high-precision reference tracking and disturbance rejection of power converters. Both controllers use a proportional-resonant regulator in the stationary frame for regulating...... the positive- and negative-sequence fundamental currents, which are known to directly influence the flow of active and reactive power in most energy conversion systems. Moreover, for the tracking or compensation of harmonics, the controllers include a repetitive control path in either the synchronous...... or stationary frame, whose inherent feedback and feedforward structure is proven to resemble a bank of resonant filters in either reference frames. Unlike other existing controllers, the proposed repetitive controllers function by introducing multiple resonant peaks at only those harmonic frequencies typically... 10. column frame for design of reinforced concrete sway frames African Journals Online (AJOL) adminstrator design of slender reinforced concrete columns in sway frames according .... concrete,. Ac = gross cross-sectional area of the columns. Step 3: Effective Buckling Length Factors. The effective buckling length factors of columns in a sway frame shall be computed by .... shall have adequate resistance to failure in a sway mode ... 11. Power to the frame: bringing sociology back to frame analysis NARCIS (Netherlands) Vliegenthart, R.; van Zoonen, L. 2011-01-01 This article critically reviews current frame and framing research in media and communication studies. It is first argued that most authors fail to distinguish between ‘frame’ and ‘framing’ and therewith produce a conceptual confusion and imprecision that is not conducive to the field. Second, it is 12. Value Framing: A Prelude to Software Problem Framing NARCIS (Netherlands) Wieringa, Roelf J.; Gordijn, Jaap; van Eck, Pascal; Cox, K.; Hall, J.G.; Rapanotti, L. 2004-01-01 Software problem framing is a way to find specifications for software. Software problem frames can be used to structure the environment of a software system (the machine) and specify desired software properties in such a way that we can show that software with these properties will help achieve the 13. New characterizations of fusion frames (frames of subspaces) Indian Academy of Sciences (India) Theory (College Park, MD, 2003) Contemp. Math. 345, Amer. Math. Soc. (RI: Provi- dence) (2004) 87–113. [4] Casazza P G and Kutyniok G, Robustness of Fusion Frames under Erasures of sub- spaces and of Local Frame Vectors, Radon transforms, geometry, and wavelets (LA: New Orleans) (2006) Contemp. Math., Amer. 14. Body frames and frame singularities for three-atom systems International Nuclear Information System (INIS) Littlejohn, R.G.; Mitchell, K.A.; Aquilanti, V.; Cavalli, S. 1998-01-01 The subject of body frames and their singularities for three-particle systems is important not only for large-amplitude rovibrational coupling in molecular spectroscopy, but also for reactive scattering calculations. This paper presents a geometrical analysis of the meaning of body frame conventions and their singularities in three-particle systems. Special attention is devoted to the principal axis frame, a certain version of the Eckart frame, and the topological inevitability of frame singularities. The emphasis is on a geometrical picture, which is intended as a preliminary study for the more difficult case of four-particle systems, where one must work in higher-dimensional spaces. The analysis makes extensive use of kinematic rotations. copyright 1998 The American Physical Society 15. Riesz Frames and Approximation of the Frame Coefficients DEFF Research Database (Denmark) Christensen, Ole 1996-01-01 A frame is a familyof elements in a Hilbert space with the propertythat every element in the Hilbert space can be written as a (infinite)linear combination of the frame elements. Frame theory describes howone can choose the corresponding coefficients, which are calledframe coefficients. From...... the mathematical point of view this isgratifying, but for applications it is a problem that the calculationrequires inversion of an operator on the Hilbert space.The projection method is introduced in order to avoid this problem.The basic idea is to consider finite subfamiliesof the frame and the orthogonal...... projection onto its span. Forfin QTR H,P_nf has a representation as a linear combinationof f_i,i=1,2,..,n, and the corresponding coefficients can be calculatedusing finite dimensional methods. We find conditions implying that thosecoefficients converge to the correct frame coefficients as n goes... 16. Growth references NARCIS (Netherlands) Buuren, S. van 2007-01-01 A growth reference describes the variation of an anthropometric measurement within a group of individuals. A reference is a tool for grouping and analyzing data and provides a common basis for comparing populations.1 A well known type of reference is the age-conditional growth diagram. The 17. Framing the frame: How task goals determine the likelihood and direction of framing effects OpenAIRE Todd McElroy; John J. Seta 2007-01-01 We examined how the goal of a decision task influences the perceived positive, negative valence of the alternatives and thereby the likelihood and direction of framing effects. In Study 1 we manipulated the goal to increase, decrease or maintain the commodity in question and found that when the goal of the task was to increase the commodity, a framing effect consistent with those typically observed in the literature was found. When the goal was to decrease, a framing effect opposite to the ty... 18. Effects of news frames on perceived risk, emotions, and learning. Directory of Open Access Journals (Sweden) Christine Otieno Full Text Available The media play a key role in forming opinions by influencing people´s understanding and perception of a topic. People gather information about topics of interest from the internet and print media, which employ various news frames to attract attention. One example of a common news frame is the human-interest frame, which emotionalizes and dramatizes information and often accentuates individual affectedness. Our study investigated effects of human-interest frames compared to a neutral-text condition with respect to perceived risk, emotions, and knowledge acquisition, and tested whether these effects can be "generalized" to common variants of the human-interest frame. Ninety-one participants read either one variant of the human-interest frame or a neutrally formulated version of a newspaper article describing the effects of invasive species in general and the Asian ladybug (an invasive species in particular. The framing was achieved by varying the opening and concluding paragraphs (about invasive species, as well as the headline. The core text (about the Asian ladybug was the same across all conditions. All outcome variables on framing effects referred to this common core text. We found that all versions of the human-interest frame increased perceived risk and the strength of negative emotions compared to the neutral text. Furthermore, participants in the human-interest frame condition displayed better (quantitative learning outcomes but also biased knowledge, highlighting a potential dilemma: Human-interest frames may increase learning, but they also lead to a rather unbalanced view of the given topic on a "deeper level". 19. Effects of News Frames on Perceived Risk, Emotions, and Learning Science.gov (United States) Otieno, Christine; Spada, Hans; Renkl, Alexander 2013-01-01 The media play a key role in forming opinions by influencing people´s understanding and perception of a topic. People gather information about topics of interest from the internet and print media, which employ various news frames to attract attention. One example of a common news frame is the human-interest frame, which emotionalizes and dramatizes information and often accentuates individual affectedness. Our study investigated effects of human-interest frames compared to a neutral-text condition with respect to perceived risk, emotions, and knowledge acquisition, and tested whether these effects can be "generalized" to common variants of the human-interest frame. Ninety-one participants read either one variant of the human-interest frame or a neutrally formulated version of a newspaper article describing the effects of invasive species in general and the Asian ladybug (an invasive species) in particular. The framing was achieved by varying the opening and concluding paragraphs (about invasive species), as well as the headline. The core text (about the Asian ladybug) was the same across all conditions. All outcome variables on framing effects referred to this common core text. We found that all versions of the human-interest frame increased perceived risk and the strength of negative emotions compared to the neutral text. Furthermore, participants in the human-interest frame condition displayed better (quantitative) learning outcomes but also biased knowledge, highlighting a potential dilemma: Human-interest frames may increase learning, but they also lead to a rather unbalanced view of the given topic on a “deeper level”. PMID:24223999 20. Independent Directors DEFF Research Database (Denmark) Ringe, Wolf-Georg 2013-01-01 This paper re-evaluates the corporate governance concept of ‘board independence’ against the disappointing experiences during the 2007-08 financial crisis. Independent or outside directors had long been seen as an essential tool to improve the monitoring role of the board. Yet the crisis revealed...... that they did not prevent firms' excessive risk taking; further, these directors sometimes showed serious deficits in understanding the business they were supposed to control, and remained passive in addressing structural problems. A closer look reveals that under the surface of seemingly unanimous consensus... 1. FRAME CATAGORIZATION OF CONVERSATIONAL INTIMACY OpenAIRE Lyubov Kit 2017-01-01 The article deals with the notion of intimacy. The frame of intimacy is studied on the basis of the linguistic parameters, analysis of text extracts and universal knowledge about intimacy. Frame analysis helped to establish the catagorization of types and nominators of intimate speech genres, their construction in static and dynamic aspects. 2. Frame Catagorization of Conversational Intimacy OpenAIRE Lyubov Kit 2017-01-01 The article deals with the notion of intimacy. The frame of intimacy is studied on the basis of the linguistic parameters, analysis of text extracts and universal knowledge about intimacy. Frame analysis helped to establish the catagorization of types and nominators of intimate speech genres, their construction in static and dynamic aspects. 3. Frames and outer frames for Hilbert C^*-modules OpenAIRE Arambašić, Ljiljana; Bakić, Damir 2015-01-01 The goal of the present paper is to extend the theory of frames for countably generated HilbertC^*$-modules over arbitrary$C^*$-algebras. In investigating the non-unital case we introduce the concept of outer frame as a sequence in the multiplier module$M(X)$that has the standard frame property when applied to elements of the ambient module$X$. Given a Hilbert$\\A$-module$X$, we prove that there is a bijective correspondence of the set of all adjointable surjections from the generalize... 4. Framed School--Frame Factors, Frames and the Dynamics of Social Interaction in School Science.gov (United States) Persson, Anders 2015-01-01 This paper aims to show how the Goffman frame perspective can be used in an analysis of school and education and how it can be combined, in such analysis, with the frame factor perspective. The latter emphasizes factors that are determined outside the teaching process, while the former stresses how actors organize their experiences and define… 5. [Reference citation]. Science.gov (United States) Brkić, Silvija 2013-01-01 Scientific and professional papers represent the information basis for scientific research and professional work. References important for the paper should be cited within the text, and listed at the end of the paper. This paper deals with different styles of reference citation. Special emphasis was placed on the Vancouver Style for reference citation in biomedical journals established by the International Committee of Medical Journal Editors. It includes original samples for citing various types of articles, both printed and electronic, as well as recommendations related to reference citation in accordance with the methodology and ethics of scientific research and guidelines for preparing manuscripts for publication. 6. serialising languages: satellite-framed, verb-framed or neither African Journals Online (AJOL) George Saad Figure 2: Verb-framed construction type (Slobin 2000: 109). 2 ... 2 An anonymous reviewer asks why we have replaced Talmy's conflation term “Ground” with ..... an S-language may predispose speakers to pay more linguistic attention to. 7. Serialising languages: Satellite-framed, verb-framed or neither ... African Journals Online (AJOL) The diversity in the coding of the core schema of motion, i.e., Path, has led to a traditional typology of languages into verb-framed and satellite-framed languages. In the former Path is encoded in verbs and in the latter it is encoded in non-verb elements that function as sisters to co-event expressing verbs such as manner ... 8. Framing of task performance strategies: effects on performance in a multiattribute dynamic decision making environment. Science.gov (United States) Nygren, T E 1997-09-01 It is well documented that the way a static choice task is "framed" can dramatically alter choice behavior, often leading to observable preference reversals. This framing effect appears to result from perceived changes in the nature or location of a person's initial reference point, but it is not clear how framing effects might generalize to performance on dynamic decision making tasks that are characterized by high workload, time constraints, risk, or stress. A study was conducted to examine the hypothesis that framing can introduce affective components to the decision making process and can influence, either favorably (positive frame) or adversely (negative frame), the implementation and use of decision making strategies in dynamic high-workload environments. Results indicated that negative frame participants were significantly impaired in developing and employing a simple optimal decision strategy relative to a positive frame group. Discussion focuses on implications of these results for models of dynamic decision making. 9. Reference Assessment Science.gov (United States) Bivens-Tatum, Wayne 2006-01-01 This article presents interesting articles that explore several different areas of reference assessment, including practical case studies and theoretical articles that address a range of issues such as librarian behavior, patron satisfaction, virtual reference, or evaluation design. They include: (1) "Evaluating the Quality of a Chat Service"… 10. Framing Effect in the Trolley Problem and Footbridge Dilemma. Science.gov (United States) Cao, Fei; Zhang, Jiaxi; Song, Lei; Wang, Shoupeng; Miao, Danmin; Peng, Jiaxi 2017-02-01 The present study investigated the effect of dilemma type, framing, and number of saved lives on moral decision making. A total of 591 undergraduates, with a mean age of 20.56 (SD = 1.37) were randomly assigned to 12 groups on the basis of a grid of two dilemma types (the trolley problem or the footbridge dilemma) by three frames (positive, neutral, or negative frame) by two different numbers of workers (5 or 15 people). The main effects of dilemma type, frame, and number of saved workers were all significant. The interaction of dilemma type and number of saved workers and the interaction of the three independent factors were significant. Results indicated that moral judgment is affected by framing. Specifically, people were more inclined to utilitarianism in the positive or neutral frame and more inclined to intuitionism in the negative frame. Furthermore, this effect can be moderated by dilemma type and number of saved lives. Implications of our results are discussed. 11. Frame dependence of spin-one angular conditions in light front dynamics International Nuclear Information System (INIS) Bakker, Bernard L. G.; Ji Chuengryong 2002-01-01 We elaborate the frame dependence of the angular conditions for spin-1 form factors. An extra angular condition is found in addition to the usual angular condition relating the four helicity amplitudes. Investigating the frame dependence of angular conditions, we find that the extra angular condition is in general as complicated as the usual one, although it becomes very simple in the q + =0 frame involving only two helicity amplitudes. It is confirmed that the angular conditions are identical in frames that are connected by kinematical transformations. The high-Q 2 behavior of the physical form factors and the limiting behavior in special reference frames are also discussed 12. Frames and counter-frames giving meaning to dementia: a framing analysis of media content. Science.gov (United States) Van Gorp, Baldwin; Vercruysse, Tom 2012-04-01 Media tend to reinforce the stigmatization of dementia as one of the most dreaded diseases in western society, which may have repercussions on the quality of life of those with the illness. The persons with dementia, but also those around them become imbued with the idea that life comes to an end as soon as the diagnosis is pronounced. The aim of this paper is to understand the dominant images related to dementia by means of an inductive framing analysis. The sample is composed of newspaper articles from six Belgian newspapers (2008-2010) and a convenience sample of popular images of the condition in movies, documentaries, literature and health care communications. The results demonstrate that the most dominant frame postulates that a human being is composed of two distinct parts: a material body and an immaterial mind. If this frame is used, the person with dementia ends up with no identity, which is in opposition to the Western ideals of personal self-fulfilment and individualism. For each dominant frame an alternative counter-frame is defined. It is concluded that the relative absence of counter-frames confirms the negative image of dementia. The inventory might be a help for caregivers and other professionals who want to evaluate their communication strategy. It is discussed that a more resolute use of counter-frames in communication about dementia might mitigate the stigma that surrounds dementia. Copyright © 2012 Elsevier Ltd. All rights reserved. 13. Analysis of frame structure of medium and small truck crane Science.gov (United States) Cao, Fuyi; Li, Jinlong; Cui, Mengkai 2018-03-01 Truck crane is an important part of hoisting machinery. Frame, as the support component of the quality of truck crane, determines the safety of crane jib load and the rationality of structural design. In this paper, the truck crane frame is a box structure, the three-dimensional model is established in CATIA software, and imported into Hyperworks software for finite element analysis. On the base of doing constraints and loads for the finite element model of the frame, the finite element static analysis is carried out. And the static stress test verifies whether the finite element model and the frame structure design are reasonable; then the free modal analysis of the frame and the analysis of the first 8 - order modal vibration deformation are carried out. The analysis results show that the maximum stress value of the frame is greater than the yield limit value of the material, and the low-order modal value is close to the excitation frequency value, which needs to be improved to provide theoretical reference for the structural design of the truck crane frame. 14. Putting Safety in the Frame Directory of Open Access Journals (Sweden) Valerie Jean O’Keeffe 2015-06-01 Full Text Available Current patient safety policy focuses nursing on patient care goals, often overriding nurses’ safety. Without understanding how nurses construct work health and safety (WHS, patient and nurse safety cannot be reconciled. Using ethnography, we examine social contexts of safety, studying 72 nurses across five Australian hospitals making decisions during patient encounters. In enacting safe practice, nurses used “frames” built from their contextual experiences to guide their behavior. Frames are produced by nurses, and they structure how nurses make sense of their work. Using thematic analysis, we identify four frames that inform nurses’ decisions about WHS: (a communicating builds knowledge, (b experiencing situations guides decisions, (c adapting procedures streamlines work, and (d team working promotes safe working. Nurses’ frames question current policy and practice by challenging how nurses’ safety is positioned relative to patient safety. Recognizing these frames can assist the design and implementation of effective WHS management. 15. Case study of a framing effect in course evaluations. Science.gov (United States) Lynöe, Niels; Juth, Niklas; Helgesson, Gert 2012-01-01 When new elements are included in the medical curriculum and the total time frame remains unchanged, established disciplines have to shorten their courses. This might bring about frustration among the teachers and students concerned, which in turn might affect how other courses are perceived. Two course evaluations, one before and one after a major change in the curriculum were compared. Comments were also analysed. We found that the students' and teachers' frustration influenced the students' evaluations of a new course in the philosophy of medicine and accordingly brought about an unintended message effect referred to as a framing effect. The results of this observational study indicate that a negative framing effect might influence course-evaluations. We suggest that this study might be used as a point of departure for further empirical studies about negative framing effects. 16. Recent references International Nuclear Information System (INIS) Ramavataram, S. 1991-01-01 In support of a continuing program of systematic evaluation of nuclear structure data, the National Nuclear Data Center maintains a complete computer file of references to the nuclear physics literature. Each reference is tagged by a keyword string, which indicates the kinds of data contained in the article. This master file of Nuclear Structure References (NSR) contains complete keyword indexes to literature published since 1969, with partial indexing of older references. Any reader who finds errors in the keyword descriptions is urged to report them to the National Nuclear Data Center so that the master NSR file can be corrected. In 1966, the first collection of Recent References was published as a separate issue of Nuclear Data Sheets. Every four months since 1970, a similar indexed bibliography to new nuclear experiments has been prepared from additions to the NSR file and published. Beginning in 1978, Recent References was cumulated annually, with the third issue completely superseding the two issues previously published during a given year. Due to publication policy changes, cumulation of Recent Reference was discontinued in 1986. The volume and issue number of all the cumulative issues published to date are given. NNDC will continue to respond to individual requests for special bibliographies on nuclear physics topics, in addition to those easily obtained from Recent References. If the required information is available from the keyword string, a reference list can be prepared automatically from the computer files. This service can be provided on request, in exchange for the timely communication of new nuclear physics results (e.g., preprints). A current copy of the NSR file may also be obtained in a standard format on magnetic tape from NNDC. Requests for special searches of the NSR file may also be directed to the National Nuclear Data Center 17. The spaces in the looking glass: stilling the frame/framing the still Directory of Open Access Journals (Sweden) Marvin E. Kirsh 2015-06-01 Full Text Available The purpose of this writing is to propose a frame of view, a form as the eternal world element, that is compatible with paradox within the history of ideas, modern discovery as they confront one another. Under special consideration are problems of representation of phenomena, life, the cosmos as the rational facility of mind confronts the physical/perceptual, and itself. Current topics in pursuit are near as diverse and numbered as are the possibilities for a world composed strictly of uniqueness able to fill infinite space; it is assumed that not all of the paths chosen in contemporary pursuits will produce coherent determinations in an appropriate frame able to accommodate a world of nominals in motion, containing motion, and is commensurate with basic physical law and the propagation of form, change from within. Intended as a potential guiding post for the aim of reason seeking to select, define and capture topics, chosen as special examples are the works of logistician/mathematician Lewis Carroll as he presents a paradox of actuality verses the reality of perception in Alice in Wonderland, the theory of relativity of Albert Einstein as he fails to elaborate a mathematics to communicate an inertial frame of reference, and the reconstruction ideas of Jacques Derrida as he refers for contrast with the scientific world view constructed of dualisms, monisms that are conceived to have no opposites. Supporting discussion is evolved from the works of Bertrand Russell, Erwin Schrodinger, Jurgen Habermas, Bronislaw Malinowski, Michel Foucault. 18. Gabor Frames in ℓ2(Z) and Linear Dependence DEFF Research Database (Denmark) Christensen, Ole; Hasannasab, Marzieh 2017-01-01 We prove that an overcomplete Gabor frame in (Formula presented.) generated by a finitely supported sequence is always linearly dependent. This is a particular case of a general result about linear dependence versus independence for Gabor systems in (Formula presented.) with modulation parameter ... 19. Hemispheric Correlates of the Rod-And-Frame Test. Science.gov (United States) Berlin, Donna F.; Languis, Marlin L. 1981-01-01 Right-handed sixth graders were administered the WISC Block Design and verbal and nonverbal versions of the Rod-and-Frame Test (RFT), measuring field dependence/independence. Results seemed to reflect a right hemisphere processing for the nonverbal RFT and a possible sex bias against girls in its traditional verbal administration. (Author/SJL) 20. The Frame Constraint on Experimentally Elicited Speech Errors in Japanese Science.gov (United States) Saito, Akie; Inoue, Tomoyoshi 2017-01-01 The so-called syllable position effect in speech errors has been interpreted as reflecting constraints posed by the frame structure of a given language, which is separately operating from linguistic content during speech production. The effect refers to the phenomenon that when a speech error occurs, replaced and replacing sounds tend to be in the… 1. Causal anomalies and the case for a preferred referential frame International Nuclear Information System (INIS) Martins, R.A. 1984-01-01 A theoretical argument supporting the idea that in some physical situations compatible with the general theory of relativity one may have very good reasons for choosing one particular reference frame in a locally Minkowskian space-time-that is, in a case where special relativity is supposed to hold, is described. (L.C.) [pt 2. Independent safety organization International Nuclear Information System (INIS) Kato, W.Y.; Weinstock, E.V.; Carew, J.F.; Cerbone, R.J.; Guppy, J.G.; Hall, R.E.; Taylor, J.H. 1985-01-01 Brookhaven National Laboratory has conducted a study on the need and feasibility of an independent organization to investigate significant safety events for the Office for Analysis and Evaluation of Operational Data, USNRC. The study consists of three parts: the need for an independent organization to investigate significant safety events, alternative organizations to conduct investigations, and legislative requirements. The determination of need was investigated by reviewing current NRC investigation practices, comparing aviation and nuclear industry practices, and interviewing a spectrum of representatives from the nuclear industry, the regulatory agency, and the public sector. The advantages and disadvantages of alternative independent organizations were studied, namely, an Office of Nuclear Safety headed by a director reporting to the Executive Director for Operations (EDO) of NRC; an Office of Nuclear Safety headed by a director reporting to the NRC Commissioners; a multi-member NTSB-type Nuclear Safety Board independent of the NRC. The costs associated with operating a Nuclear Safety Board were also included in the study. The legislative requirements, both new authority and changes to the existing NRC legislative authority, were studied. 134 references 3. Frames of exponentials:lower frame bounds for finite subfamilies, and approximation of the inverse frame operator DEFF Research Database (Denmark) Christensen, Ole; Lindner, Alexander M 2001-01-01 We give lower frame bounds for finite subfamilies of a frame of exponentials {e(i lambdak(.))}k is an element ofZ in L-2(-pi,pi). We also present a method for approximation of the inverse frame operator corresponding to {e(i lambdak(.))}k is an element ofZ, where knowledge of the frame bounds for... 4. Healing in Herero culture and Namibian African independent churches Directory of Open Access Journals (Sweden) Selaelo T. Kgatla 2015-09-01 Full Text Available The current phenomenon of Namibian African Independent Churches (NAICs draws attention from various people in civil society in Namibia. Although the ministries of NAICs are engaged with activities which are unusual for Christian churches, such as healing the people, fighting against evil spirits and power, performing certain rituals, prophesying and leading the worship services with African Traditional Religion (ATR as a frame of reference in 21st century, they do have a very big influence on various aspects of society in Namibia, which cannot be ignored. This is because those activities are familiar to the everyday lives of Africans and in touch with their culture. With regards to this, this article focuses on the causes of integration or harmony between the Herero culture and the NAICs. 5. Uranium reference materials International Nuclear Information System (INIS) Donivan, S.; Chessmore, R. 1987-07-01 The Technical Measurements Center has prepared uranium mill tailings reference materials for use by remedial action contractors and cognizant federal and state agencies. Four materials were prepared with varying concentrations of radionuclides, using three tailings materials and a river-bottom soil diluent. All materials were ground, dried, and blended thoroughly to ensure homogeneity. The analyses on which the recommended values for nuclides in the reference materials are based were performed, using independent methods, by the UNC Geotech (UNC) Chemistry Laboratory, Grand Junction, Colorado, and by C.W. Sill (Sill), Idaho National Engineering Laboratory, Idaho Falls, Idaho. Several statistical tests were performed on the analytical data to characterize the reference materials. Results of these tests reveal that the four reference materials are homogeneous and that no large systematic bias exists between the analytical methods used by Sill and those used by TMC. The average values for radionuclides of the two data sets, representing an unbiased estimate, were used as the recommended values for concentrations of nuclides in the reference materials. The recommended concentrations of radionuclides in the four reference materials are provided. Use of these reference materials will aid in providing uniform standardization among measurements made by remedial action contractors. 11 refs., 9 tabs 6. The Experimental Research on Seismic Capacity of the Envelope Systems with Steel Frame Science.gov (United States) Li, Jiuyang; Wang, Bingbing; Li, Hengxu 2017-09-01 In this paper, according to the present application situation of the external envelope systems steel frame in the severe cold region, the stuffed composite wall panels are improved, the flexible connection with the steel frame is designed, the reduced scale specimens are made, the seismic capacity test is made and some indexes of the envelope systems such as bearing capacity, energy consumption and ductility, etc. are compared, which provide reference for the development and application of the steel frame envelope systems. 7. Patch-based frame interpolation for old films via the guidance of motion paths Science.gov (United States) Xia, Tianran; Ding, Youdong; Yu, Bing; Huang, Xi 2018-04-01 Due to improper preservation, traditional films will appear frame loss after digital. To deal with this problem, this paper presents a new adaptive patch-based method of frame interpolation via the guidance of motion paths. Our method is divided into three steps. Firstly, we compute motion paths between two reference frames using optical flow estimation. Then, the adaptive bidirectional interpolation with holes filled is applied to generate pre-intermediate frames. Finally, using patch match to interpolate intermediate frames with the most similar patches. Since the patch match is based on the pre-intermediate frames that contain the motion paths constraint, we show a natural and inartificial frame interpolation. We test different types of old film sequences and compare with other methods, the results prove that our method has a desired performance without hole or ghost effects. 8. Message Framing and Physical Activity Promotion in Colorectal Cancer Survivors. Science.gov (United States) Hirschey, Rachel; Lipkus, Isaac; Jones, Lee; Mantyh, Christopher; Sloane, Richard; Demark-Wahnefried, Wendy 2016-11-01 To test effects of gain-framed versus loss-framed mailed brochures on increasing physical activity (PA) among colorectal cancer (CRC) survivors. . Randomized trial with repeated measures at baseline, 1 month, and 12 months postintervention. . Mail recruitment from tumor registries. . 148 inactive CRC survivors who had completed primary therapy. . PA and constructs from the Theory of Planned Behavior (TPB) were assessed at baseline, 1 month, and 12 months. Participants were randomized to receive pamphlets describing PA benefits (gain framed) or disadvantages of not being physically active (loss framed). Baseline characteristics were compared using descriptive statistics. Repeated measures linear models were used to test PA changes. . Minutes of PA and TPB constructs. . Significant PA increases were observed in both study arms. Results did not differ by message frame. At one month, about 25% of previously inactive participants increased activity to national recommendations. Those who increased PA compared to those who did not had higher baseline scores on subjective norms, perceived behavioral control, and PA intentions. . Independent of message framing, mailed brochures are highly effective in producing within-subject short- and long-term increases in PA. . CRC survivors may increase short- and long-term levels of PA by receiving inexpensive print brochures. 9. C-connected frame congruences Directory of Open Access Journals (Sweden) Dharmanand Baboolal 2017-01-01 Full Text Available We discuss the congruences$theta$that are connected as elements of the (totally disconnected congruence frame$CF L$, and show that they are in a one-to-one correspondence with the completely prime elements of$L$, giving an explicit formula. Then we investigate those frames$L$with enough connected congruences to cover the whole of$CF L$. They are, among others, shown to be$T_D$-spatial; characteristics for some special cases (Boolean, linear, scattered and Noetherian are presented. 10. Sparsity and spectral properties of dual frames DEFF Research Database (Denmark) Krahmer, Felix; Kutyniok, Gitta; Lemvig, Jakob 2013-01-01 We study sparsity and spectral properties of dual frames of a given finite frame. We show that any finite frame has a dual with no more than$n^2$non-vanishing entries, where$n$denotes the ambient dimension, and that for most frames no sparser dual is possible. Moreover, we derive an expressio... 11. Some equalities and inequalities for fusion frames OpenAIRE Guo, Qianping; Leng, Jinsong; Li, Houbiao 2016-01-01 Fusion frames have some properties similar to those of frames in Hilbert spaces, but not all of their properties are similar. Some authors have established some equalities and inequalities for conventional frames. In this paper, we give some equalities and inequalities for fusion frames. Our results generalize and improve the remarkable results which have been obtained by Balan, Casazza and G?vruta etc. 12. 49 CFR 393.201 - Frames. Science.gov (United States) 2010-10-01 ... 49 Transportation 5 2010-10-01 2010-10-01 false Frames. 393.201 Section 393.201 Transportation... SAFE OPERATION Frames, Cab and Body Components, Wheels, Steering, and Suspension Systems § 393.201 Frames. (a) The frame or chassis of each commercial motor vehicle shall not be cracked, loose, sagging or... 13. Key Frame Extraction in the Summary Space. Science.gov (United States) Li, Xuelong; Zhao, Bin; Lu, Xiaoqiang; Xuelong Li; Bin Zhao; Xiaoqiang Lu; Lu, Xiaoqiang; Li, Xuelong; Zhao, Bin 2018-06-01 Key frame extraction is an efficient way to create the video summary which helps users obtain a quick comprehension of the video content. Generally, the key frames should be representative of the video content, meanwhile, diverse to reduce the redundancy. Based on the assumption that the video data are near a subspace of a high-dimensional space, a new approach, named as key frame extraction in the summary space, is proposed for key frame extraction in this paper. The proposed approach aims to find the representative frames of the video and filter out similar frames from the representative frame set. First of all, the video data are mapped to a high-dimensional space, named as summary space. Then, a new representation is learned for each frame by analyzing the intrinsic structure of the summary space. Specifically, the learned representation can reflect the representativeness of the frame, and is utilized to select representative frames. Next, the perceptual hash algorithm is employed to measure the similarity of representative frames. As a result, the key frame set is obtained after filtering out similar frames from the representative frame set. Finally, the video summary is constructed by assigning the key frames in temporal order. Additionally, the ground truth, created by filtering out similar frames from human-created summaries, is utilized to evaluate the quality of the video summary. Compared with several traditional approaches, the experimental results on 80 videos from two datasets indicate the superior performance of our approach. 14. Frame-based safety analysis approach for decision-based errors International Nuclear Information System (INIS) Fan, Chin-Feng; Yihb, Swu 1997-01-01 A frame-based approach is proposed to analyze decision-based errors made by automatic controllers or human operators due to erroneous reference frames. An integrated framework, Two Frame Model (TFM), is first proposed to model the dynamic interaction between the physical process and the decision-making process. Two important issues, consistency and competing processes, are raised. Consistency between the physical and logic frames makes a TFM-based system work properly. Loss of consistency refers to the failure mode that the logic frame does not accurately reflect the state of the controlled processes. Once such failure occurs, hazards may arise. Among potential hazards, the competing effect between the controller and the controlled process is the most severe one, which may jeopardize a defense-in-depth design. When the logic and physical frames are inconsistent, conventional safety analysis techniques are inadequate. We propose Frame-based Fault Tree; Analysis (FFTA) and Frame-based Event Tree Analysis (FETA) under TFM to deduce the context for decision errors and to separately generate the evolution of the logical frame as opposed to that of the physical frame. This multi-dimensional analysis approach, different from the conventional correctness-centred approach, provides a panoramic view in scenario generation. Case studies using the proposed techniques are also given to demonstrate their usage and feasibility 15. Flexible body dynamics in a local frame with explicitly predicted motion DEFF Research Database (Denmark) Kawamoto, A.; Krenk, Steen; Suzuki, A. 2010-01-01 This paper deals with formulation of dynamics of a moving flexible body in a local frame of reference. In a conventional approach the local frame is normally fixed to the corresponding body and always represents the positions and angles of the body: the positions and angles are represented by Car... 16. Analysis of Truss Frames by Method of the Stiffness Matrix Science.gov (United States) 1990-12-01 of the web members of the truss. There also are variations in the truss frame given by the geometric shape of the frame, also referred to in some...at the elastic center, 0 (Figure .3.2), are: R AX = Wix - Hot RBX W2x -Ho, RAY =WIY + Vo, (1) RBy WLy - Vo, MAB =- Mo + CH. + aVo + CMA, MBA =M - CH...o Co Ce Substituting the results of Equation (7) into Equations (1), x c D x RAY = Wix + + -- (eA - GO - D (8)C x C x C cx x cx AY a D RAY 17. Framing and misperception in public good experiments DEFF Research Database (Denmark) Fosgaard, Toke Reinholt; Hansen, Lars Gårn; Wengström, Erik Roland 2017-01-01 Earlier studies have found that framing has substantial impact on the degree of cooperation observed in public good experiments. We show that the way the public good game is framed affects misperceptions about the incentives of the game. Moreover, we show that such framing-induced differences...... in misperceptions are linked to the framing effect on subjects' cooperation behavior. When we do not control for the different levels of misperceptions between frames, we observe a significant framing effect on subjects’ cooperation preferences. However, this framing effect becomes insignificant once we remove... 18. Writing More Informative Letters of Reference OpenAIRE Wright, Scott M; Ziegelstein, Roy C 2004-01-01 Writing a meaningful and valuable letter of reference is not an easy task. Several factors influence the quality of any letter of reference. First, the accuracy and reliability of the writer's impressions and judgment depend on how well he knows the individual being described. Second, the writer's frame of reference, which is determined by the number of persons at the same level that he has worked with, will impact the context and significance of his beliefs and estimations. Third, the letter... 19. Media framing and social movements NARCIS (Netherlands) Vliegenthart, R.; Snow, D.A.; Della Porta, D.; Klandermans, B.; McAdam, D. 2013-01-01 In their study of media content, mass communication scholars commonly rely on Entman's (1993: 52) definition of framing: "[selecting] some aspects of a perceived reality and make them more salient in a communicating text, in such a way as to promote a particular problem definition, causal 20. On framed simple Lie groups OpenAIRE MINAMI, Haruo 2016-01-01 For a compact simple Lie group$G$, we show that the element$[G, \\mathcal{L}] \\in \\pi^S_*(S^0)$represented by the pair$(G, \\mathcal{L})$is zero, where$\\mathcal{L}$denotes the left invariant framing of$G\$. The proof relies on the method of E. Ossa [Topology, 21 (1982), 315–323].
1. Handedness differences in information framing.
Science.gov (United States)
Jasper, John D; Fournier, Candice; Christman, Stephen D
2014-02-01
2. Meta framing and polyphonic structures
DEFF Research Database (Denmark)
Pedersen, Karsten
2017-01-01
in various ways in BT’s 2012 coverage of a doping case involving Riis. In this article I investigate the way in which BT meta frames itself and its own actions in order to show and underline the seriousness with which BT treats sports journalism. The study is part of a recurring Danish project harvesting...
3. Frame Rate and Human Vision
Science.gov (United States)
Watson, Andrew B.
2012-01-01
To enhance the quality of the theatre experience, the film industry is interested in achieving higher frame rates for capture and display. In this talk I will describe the basic spatio-temporal sensitivities of human vision, and how they respond to the time sequence of static images that is fundamental to cinematic presentation.
4. Framing the future of fracking
NARCIS (Netherlands)
Metze, Tamara
2017-01-01
Hydraulic fracturing is a technology developed to improve and increase the production of natural gas. In many countries, including the Netherlands, it has caused environmental controversies. In these controversies, 'futurity framing' may open up debates for alternative paradigms such as
5. Frames and generalized shift-invariant systems
DEFF Research Database (Denmark)
Christensen, Ole
2004-01-01
With motivation from the theory of Hilbert-Schmidt operators we review recent topics concerning frames in L 2 (R) and their duals. Frames are generalizations of orthonormal bases in Hilbert spaces. As for an orthonormal basis, a frame allows each element in the underlying Hilbert space...... to be written as an unconditionally convergent infinite linear combination of the frame elements; however, in contrast to the situation for a basis, the coefficients might not be unique. We present the basic facts from frame theory and the motivation for the fact that most recent research concentrates on tight...... frames or dual frame pairs rather than general frames and their canonical dual. The corresponding results for Gabor frames and wavelet frames are discussed in detail....
6. On the structures of Grassmannian frames
OpenAIRE
Haas IV, John I.; Casazza, Peter G.
2017-01-01
A common criterion in the design of finite Hilbert space frames is minimal coherence, as this leads to error reduction in various signal processing applications. Frames that achieve minimal coherence relative to all unit-norm frames are called Grassmannian frames, a class which includes the well-known equiangular tight frames. However, the notion of "coherence minimization" varies according to the constraints of the ambient optimization problem, so there are other types of "minimally coherent...
7. Sensitivity of annual and seasonal reference crop ...
scheduling and water resources management. Ref- ... time, and refers to evapotranspiration rate from a reference ... variable per unit increase in independent variable. Sensitivity ...... Pereira L S 2007 Relating water productivity and crop.
8. Confidence in the safety of blood for transfusion: the effect of message framing.
Science.gov (United States)
Farrell, K; Ferguson, E; James, V; Lowe, K C
2001-11-01
Blood transfusion is a universally used, life-saving medical intervention. However, there are increasing concerns among patients about blood safety. This study investigates the effect of message framing, a means of presenting information, on confidence in blood transfusion safety. The same factual information regarding the safety of blood for transfusion was presented to a sample of 254 adult students (donors and nondonors) as either a gain frame (lives saved), a loss frame (lives lost), or a combined frame (a loss frame expressed in a positive context). This provided a basic two-way, between-subjects design with 1) blood donation history (donors vs. nondonors) and 2) message frame (gain, loss, and combined) functioning as the between-groups factors. It was hypothesized that participants would consider blood safer if information was presented as a gain frame. The role of stress appraisals as potential mediators of the framing effect was also explored. As predicted, participants receiving the gain-frame information were significantly more confident of the safety of blood for transfusion than those receiving loss-frame information or both. This was unaffected by donation history or appraisals of stress associated with transfusion. The extent to which blood was considered safe was negatively associated, independently of framing effects, with perceptions that transfusion was threatening. Information about transfusion should be conveyed to patients in a form focusing on the positive, rather than the negative, known facts about the safety of blood.
9. Veja o MST! - Um frame revelado
Directory of Open Access Journals (Sweden)
2005-01-01
Full Text Available Esta é uma análise de duas reportagens jornalísticas publicadas em 3/04/2002, referentes a um único episódio: a invasão, liderada pelo Movimento dos Trabalhadores Sem-Terra (MST, da Fazenda Córrego da Ponte, situada em Buritis, Minas Gerais, de propriedade da família do então presidente Fernando Henrique Cardoso, ocorrida em 23/03/2002. Tal análise revela, no texto da Revista Veja (p. 46 a 50, a construção, principalmente através de recursos lexicais, de um determinado modelo cognitivo idealizado - frame - (Fauconnier, 1997 - subjacente à macro-estrutura do texto, o que não ocorre em relação à reportagem da Revista Isto é (p. 31 a 34. A existência de tal frame, compartilhada culturalmente por escritores e leitores, leva, por parte destes, a interpretações maniqueístas do evento sendo reportado.The present work is an analysis of two magazine reports referring to the episode of the invasion of Córrego da Ponte Farm, situated in Buritis, MG, which happened on March 23rd, 2002, led by the Landless Workers Movement (MST. Córrego da Ponte is property of the family of Fernando Henrique Cardoso (The president of Brazil at that time. The first of those reports (Veja Magazine, April 3rd, 2002, p. 46 to 50 is seen in details, since it presents elements of an idealized cognitive model - frame (Fauconnier, 1997 underlying the superstructure of the text. The existence of such frame, revealed by certain linguistic elements, especially the lexical choice, tends to raise dualistic interpretations of the socio-political event being reported. The second one (Isto é Magazine, edition 1696, April 03rd, 2002, p. 31 to 34 is taken as a differentiated parameter, for comparison to the analysis proposal for the first report.
10. Dynamics of entanglement under decoherence in noninertial frames
International Nuclear Information System (INIS)
Shi Jia-Dong; Wu Tao; Song Xue-Ke; Ye Liu
2014-01-01
In this paper, we investigate the entanglement dynamics of a two-qubit entangled state coupled with its noisy environment, and plan to utilize weak measurement and quantum reversal measurement to study the entanglement dynamics under different decoherence channels in noninertial frames. Through the calculations and analyses, it is shown that the weak measurement can prevent entanglement from coupling to the amplitude damping channel, while the system is under the phase damping and flip channels. This protection protocol cannot prevent entanglement but will accelerate the death of entanglement. In addition, if the system is in the noninertial reference frame, then the effect of weak measurement will be weakened for the amplitude damping channel. Nevertheless, for other decoherence channels, the Unruh effect does not affect the quantum weak measurement, the only exception is that the maximum value of entanglement is reduced to √2/2 of the original value in the inertial frames. (general)
11. Frame model of knowledge in quality control systems
Energy Technology Data Exchange (ETDEWEB)
Macherauskas, V.Yu.
1982-09-01
The purpose of this article is to develop a semiotic model for representation of data and knowledge in a system for supplying operational information to management personnel on the progress of a technological process, with the aim of enabling an analysis of deviations of product quality and formulation of recommendations to the technologists as to how to eliminate them. Since any knowledge of people that can be realistically utilized in machine systems is represented in natural language form, special languages for representation of knowledge, based on the concept of frames, are being developed for formation of semiotic models in computers. This article defines the frames, followed by a description of a mechanism of knowledge manipulation and of some aspects of realization of a frame model of knowledge. 9 references.
12. Ultra-fast framing camera tube
Science.gov (United States)
Kalibjian, Ralph
1981-01-01
An electronic framing camera tube features focal plane image dissection and synchronized restoration of the dissected electron line images to form two-dimensional framed images. Ultra-fast framing is performed by first streaking a two-dimensional electron image across a narrow slit, thereby dissecting the two-dimensional electron image into sequential electron line images. The dissected electron line images are then restored into a framed image by a restorer deflector operated synchronously with the dissector deflector. The number of framed images on the tube's viewing screen is equal to the number of dissecting slits in the tube. The distinguishing features of this ultra-fast framing camera tube are the focal plane dissecting slits, and the synchronously-operated restorer deflector which restores the dissected electron line images into a two-dimensional framed image. The framing camera tube can produce image frames having high spatial resolution of optical events in the sub-100 picosecond range.
13. Variance based OFDM frame synchronization
Directory of Open Access Journals (Sweden)
Z. Fedra
2012-04-01
Full Text Available The paper deals with a new frame synchronization scheme for OFDM systems and calculates the complexity of this scheme. The scheme is based on the computing of the detection window variance. The variance is computed in two delayed times, so a modified Early-Late loop is used for the frame position detection. The proposed algorithm deals with different variants of OFDM parameters including guard interval, cyclic prefix, and has good properties regarding the choice of the algorithm's parameters since the parameters may be chosen within a wide range without having a high influence on system performance. The verification of the proposed algorithm functionality has been performed on a development environment using universal software radio peripheral (USRP hardware.
14. Predicting the Strength of Online News Frames
Directory of Open Access Journals (Sweden)
Hrvoje Jakopović
2017-10-01
Full Text Available Framing theory is one of the most significant approaches to understanding media and their potential impact on publics. Leaving aside that fact, the author finds that publicity effects seem to be dispersed and difficult to catch for public relations. This article employs a specific research design, which could be applied to public relations practice, namely with a view to observing correlations between specific media frames and individual frames. The approach is based on the typology of news frames. The author attributes negative, positive and neutral determinants to the types of frames in his empirical research. Online news regarding three transport organizations and the accompanying user comments (identified as negative, positive and neutral are analysed by means of the method of content and sentiment analysis. The author recognizes user comments and reviews as individual frames that take part in the creation of online image. Furthermore, he identifies the types of media frames as well as individual frames manifested as image, and undertakes correlation research in order to establish their prediction potential. The results expose the most frequently used types of media frames concerning the transport domain. The media are keen to report through the attribution of responsibility frame, and after that, through the economic frame and the conflict frame, but, on the other hand, they tend to neglect the human interest frame and the morality frame. The results show that specific types of news frames enable better prediction of user reactions. The economic frame and the human interest frame therefore represent the most predictable types of frame.
15. Influence of the Pixel Sizes of Reference Computed Tomography on Single-photon Emission Computed Tomography Image Reconstruction Using Conjugate-gradient Algorithm.
Science.gov (United States)
Okuda, Kyohei; Sakimoto, Shota; Fujii, Susumu; Ida, Tomonobu; Moriyama, Shigeru
The frame-of-reference using computed-tomography (CT) coordinate system on single-photon emission computed tomography (SPECT) reconstruction is one of the advanced characteristics of the xSPECT reconstruction system. The aim of this study was to reveal the influence of the high-resolution frame-of-reference on the xSPECT reconstruction. 99m Tc line-source phantom and National Electrical Manufacturers Association (NEMA) image quality phantom were scanned using the SPECT/CT system. xSPECT reconstructions were performed with the reference CT images in different sizes of the display field-of-view (DFOV) and pixel. The pixel sizes of the reconstructed xSPECT images were close to 2.4 mm, which is acquired as originally projection data, even if the reference CT resolution was varied. The full width at half maximum (FWHM) of the line-source, absolute recovery coefficient, and background variability of image quality phantom were independent on the sizes of DFOV in the reference CT images. The results of this study revealed that the image quality of the reconstructed xSPECT images is not influenced by the resolution of frame-of-reference on SPECT reconstruction.
16. Sovereignty Frames and Sovereignty Claims
OpenAIRE
Walker, Neil
2013-01-01
This essay argues that much of the contemporary confusion and controversy over the meaning and continuing utility of the concept of sovereignty stems from a failure to distinguish between sovereignty as a deep framing device for making sense of the modern legal and political word on the one hand, and the particular claims which are made on behalf of particular institutions, agencies, rules or other entities to possess sovereign authority on the other. The essay begins by providing a basic acc...
17. Orthogonal Multiwavelet Frames in L2Rd
Directory of Open Access Journals (Sweden)
Liu Zhanwei
2012-01-01
Full Text Available We characterize the orthogonal frames and orthogonal multiwavelet frames in L2Rd with matrix dilations of the form (Df(x=detAf(Ax, where A is an arbitrary expanding d×d matrix with integer coefficients. Firstly, through two arbitrarily multiwavelet frames, we give a simple construction of a pair of orthogonal multiwavelet frames. Then, by using the unitary extension principle, we present an algorithm for the construction of arbitrarily many orthogonal multiwavelet tight frames. Finally, we give a general construction algorithm for orthogonal multiwavelet tight frames from a scaling function.
18. Spacetime transformations from a uniformly accelerated frame
International Nuclear Information System (INIS)
Friedman, Yaakov; Scarr, Tzvi
2013-01-01
We use the generalized Fermi–Walker transport to construct a one-parameter family of inertial frames which are instantaneously comoving to a uniformly accelerated observer. We explain the connection between our approach and that of Mashhoon. We show that our solutions of uniformly accelerated motion have constant acceleration in the comoving frame. Assuming the weak hypothesis of locality, we obtain local spacetime transformations from a uniformly accelerated frame K′ to an inertial frame K. The spacetime transformations between two uniformly accelerated frames with the same acceleration are Lorentz. We compute the metric at an arbitrary point of a uniformly accelerated frame. (paper)
19. Non-minimal Higgs inflation and frame dependence in cosmology
International Nuclear Information System (INIS)
Steinwachs, Christian F.; Kamenshchik, Alexander Yu.
2013-01-01
We investigate a very general class of cosmological models with scalar fields non-minimally coupled to gravity. A particular representative in this class is given by the non-minimal Higgs inflation model in which the Standard Model Higgs boson and the inflaton are described by one and the same scalar particle. While the predictions of the non-minimal Higgs inflation scenario come numerically remarkably close to the recently discovered mass of the Higgs boson, there remains a conceptual problem in this model that is associated with the choice of the cosmological frame. While the classical theory is independent of this choice, we find by an explicit calculation that already the first quantum corrections induce a frame dependence. We give a geometrical explanation of this frame dependence by embedding it into a more general field theoretical context. From this analysis, some conceptional points in the long lasting cosmological debate: 'Jordan frame vs. Einstein frame' become more transparent and in principle can be resolved in a natural way.
20. Non-minimal Higgs inflation and frame dependence in cosmology
Energy Technology Data Exchange (ETDEWEB)
Steinwachs, Christian F. [School of Mathematical Sciences, University of Nottingham University Park, Nottingham, NG7 2RD (United Kingdom); Kamenshchik, Alexander Yu. [Dipartimento di Fisica e Astronomia and INFN, Via Irnerio 46, 40126 Bologna, Italy and L.D. Landau Institute for Theoretical Physics of the Russian Academy of Sciences, Kosygin str. 2, 119334 Moscow (Russian Federation)
2013-02-21
We investigate a very general class of cosmological models with scalar fields non-minimally coupled to gravity. A particular representative in this class is given by the non-minimal Higgs inflation model in which the Standard Model Higgs boson and the inflaton are described by one and the same scalar particle. While the predictions of the non-minimal Higgs inflation scenario come numerically remarkably close to the recently discovered mass of the Higgs boson, there remains a conceptual problem in this model that is associated with the choice of the cosmological frame. While the classical theory is independent of this choice, we find by an explicit calculation that already the first quantum corrections induce a frame dependence. We give a geometrical explanation of this frame dependence by embedding it into a more general field theoretical context. From this analysis, some conceptional points in the long lasting cosmological debate: 'Jordan frame vs. Einstein frame' become more transparent and in principle can be resolved in a natural way.
1. Mars Science Laboratory Frame Manager for Centralized Frame Tree Database and Target Pointing
Science.gov (United States)
Kim, Won S.; Leger, Chris; Peters, Stephen; Carsten, Joseph; Diaz-Calderon, Antonio
2013-01-01
The FM (Frame Manager) flight software module is responsible for maintaining the frame tree database containing coordinate transforms between frames. The frame tree is a proper tree structure of directed links, consisting of surface and rover subtrees. Actual frame transforms are updated by their owner. FM updates site and saved frames for the surface tree. As the rover drives to a new area, a new site frame with an incremented site index can be created. Several clients including ARM and RSM (Remote Sensing Mast) update their related rover frames that they own. Through the onboard centralized FM frame tree database, client modules can query transforms between any two frames. Important applications include target image pointing for RSM-mounted cameras and frame-referenced arm moves. The use of frame tree eliminates cumbersome, error-prone calculations of coordinate entries for commands and thus simplifies flight operations significantly.
2. Characterization of Oblique Dual Frame Pairs
DEFF Research Database (Denmark)
Christensen, Ole; Eldar, Yonina
2006-01-01
Given a frame for a subspace W of a Hilbert space H, we consider all possible families of oblique dual frame vectors on an appropriately chosen subspace V. In place of the standard description, which involves computing the pseudoinverse of the frame operator, we develop an alternative characteriz...... for the case of shift-invariant spaces with a single generator. The theory is also adapted to the standard frame setting in which the original and dual frames are defined on the same space. Copyright (C) 2006 Hindawi Publishing Corporation. All rights reserved.......Given a frame for a subspace W of a Hilbert space H, we consider all possible families of oblique dual frame vectors on an appropriately chosen subspace V. In place of the standard description, which involves computing the pseudoinverse of the frame operator, we develop an alternative...
3. 100-ps framing-camera tube
International Nuclear Information System (INIS)
Kalibjian, R.
1978-01-01
The optoelectronic framing-camera tube described is capable of recording two-dimensional image frames with high spatial resolution in the <100-ps range. Framing is performed by streaking a two-dimensional electron image across narrow slits. The resulting dissected electron line images from the slits are restored into framed images by a restorer deflector operating synchronously with the dissector deflector. The number of framed images on the tube's viewing screen equals the number of dissecting slits in the tube. Performance has been demonstrated in a prototype tube by recording 135-ps-duration framed images of 2.5-mm patterns at the cathode. The limitation in the framing speed is in the external drivers for the deflectors and not in the tube design characteristics. Faster frame speeds in the <100-ps range can be obtained by use of faster deflection drivers
4. Self- and Other-Referent Criteria of Career Success.
Science.gov (United States)
Heslin, Peter A.
2003-01-01
Business students (n=71) evaluated their career success thus far. Framed by social comparison theory, results showed that 68% used other-referent criteria to assess their success. Participants who believed that ability and personality are fixed attributes had greater reliance on other-referent criteria. (Contains 100 references.) (SK)
5. Framing, intentions, and trust-choice incompatibility
NARCIS (Netherlands)
Keren, G.B.
2007-01-01
The present paper examines how framing of messages and the intentions inferred from different—positive vs. negative—framings, interact with the development of trust. Empirical evidence is presented showing that different, logically equivalent, frames are supposedly interpreted as implying different
6. Computable Frames in Computable Banach Spaces
Directory of Open Access Journals (Sweden)
S.K. Kaushik
2016-06-01
Full Text Available We develop some parts of the frame theory in Banach spaces from the point of view of Computable Analysis. We define computable M-basis and use it to construct a computable Banach space of scalar valued sequences. Computable Xd frames and computable Banach frames are also defined and computable versions of sufficient conditions for their existence are obtained.
7. Information Leakage from Logically Equivalent Frames
Science.gov (United States)
Sher, Shlomi; McKenzie, Craig R. M.
2006-01-01
Framing effects are said to occur when equivalent frames lead to different choices. However, the equivalence in question has been incompletely conceptualized. In a new normative analysis of framing effects, we complete the conceptualization by introducing the notion of information equivalence. Information equivalence obtains when no…
8. Influence of framing on medical decision making
OpenAIRE
Feng, Jun; Gong, Jingjing; Huang, Yonghua; Wei, Yazhou; Zhang, Weiwei; Zhang, Yan
2013-01-01
Numerous studies have demonstrated the robustness of the framing effect in a variety of contexts, especially in medical decision making. Unfortunately, research is still inconsistent as to how so many variables impact framing effects in medical decision making. Additionally, much attention should be paid to the framing effect not only in hypothetical scenarios but also in clinical experience.
9. Influence of framing on medical decision making.
Science.gov (United States)
Gong, Jingjing; Zhang, Yan; Feng, Jun; Huang, Yonghua; Wei, Yazhou; Zhang, Weiwei
2013-01-01
Numerous studies have demonstrated the robustness of the framing effect in a variety of contexts, especially in medical decision making. Unfortunately, research is still inconsistent as to how so many variables impact framing effects in medical decision making. Additionally, much attention should be paid to the framing effect not only in hypothetical scenarios but also in clinical experience.
10. Influence of framing on medical decision making
Science.gov (United States)
Gong, Jingjing; Zhang, Yan; Feng, Jun; Huang, Yonghua; Wei, Yazhou; Zhang, Weiwei
2013-01-01
Numerous studies have demonstrated the robustness of the framing effect in a variety of contexts, especially in medical decision making. Unfortunately, research is still inconsistent as to how so many variables impact framing effects in medical decision making. Additionally, much attention should be paid to the framing effect not only in hypothetical scenarios but also in clinical experience. PMID:27034630
11. Evaluation and the Framing of Race
Science.gov (United States)
House, Ernest R.
2017-01-01
Racial framing can have strong effects on programs, policies, and even evaluations. Racial framing developed as a justification for the exploitation of minorities and has been a primary causal factor in the persistence of racism. By being aware of its pattern, structure, origins, and how racial framing generates effects, we can significantly…
12. 10 CFR 710.35 - Time frames.
Science.gov (United States)
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Time frames. 710.35 Section 710.35 Energy DEPARTMENT OF... Matter or Special Nuclear Material Miscellaneous § 710.35 Time frames. Statements of time established for processing aspects of a case under this subpart are the agency's desired time frames in implementing the...
13. 21 CFR 886.5842 - Spectacle frame.
Science.gov (United States)
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Spectacle frame. 886.5842 Section 886.5842 Food... DEVICES OPHTHALMIC DEVICES Therapeutic Devices § 886.5842 Spectacle frame. (a) Identification. A spectacle frame is a device made of metal or plastic intended to hold prescription spectacle lenses worn by a...
14. Cooperation, framing and political attitudes
DEFF Research Database (Denmark)
Fosgaard, Toke Reinholt; Hansen, Lars Gårn; Wengström, Erik Roland
This paper shows that political attitudes are linked to cooperative behavior in an incentivized experiment with a large sample randomly drawn from the Danish population. However, this relationship depends on the way the experiment is framed. In the standard game in which subjects give to a public...... good, contributions are the same regardless of political attitudes. In an economically equivalent version, in which subjects take from a public good, left-wingers cooperate significantly more than subjects in the middle or to the right of the political spectrum. Through simulation techniques we find...
15. Meta framing and polyphonic structures
DEFF Research Database (Denmark)
Pedersen, Karsten
2017-01-01
in various ways in BT’s 2012 coverage of a doping case involving Riis. In this article I investigate the way in which BT meta frames itself and its own actions in order to show and underline the seriousness with which BT treats sports journalism. The study is part of a recurring Danish project harvesting......The present case study deals with the Danish tabloid BT’s coverage of Cycling team owner Bjarne Riis’s possible knowledge of doping use in his cycling teams. BT sees itself as a sports paper and tries to signal that it takes sports coverage as seriously other kinds of news. We see that reflected...
16. ostglacial rebound from VLBI Geodesy: On Establishing Vertical Reference
Science.gov (United States)
Argus, Donald .
1996-01-01
I propose that a useful reference frame for vertical motions is that found by minimizing differences between vertical motions observed with VLBI [Ma and Ryan, 1995] and predictions from postglacial rebound predictions [Peltier, 1995].
17. Massively Parallel Dimension Independent Adaptive Metropolis
KAUST Repository
Chen, Yuxin
2015-01-01
parameter dimension, by respecting the variance, for Gaussian targets. The result- ing algorithm, referred to as the dimension-independent adaptive Metropolis (DIAM) algorithm, also shows improved performance with respect to adaptive Metropolis on non
18. Message framing in social networking sites.
Science.gov (United States)
Kao, Danny Tengti; Chuang, Shih-Chieh; Wang, Sui-Min; Zhang, Lei
2013-10-01
Online social networking sites represent significant new opportunities for Internet advertisers. However, results based on the real world cannot be generalized to all virtual worlds. In this research, the moderating effects of need for cognition (NFC) and knowledge were applied to examine the impact of message framing on attitudes toward social networking sites. A total of 216 undergraduates participated in the study. Results reveal that for social networking sites, while high-NFC individuals form more favorable attitudes toward negatively framed messages than positively framed messages, low-NFC individuals form more favorable attitudes toward positively framed messages than negatively framed messages. In addition, low-knowledge individuals demonstrate more favorable attitudes toward negatively framed messages than positively framed messages; however, the framing effect does not differentially affect the attitudes of high-knowledge individuals. Furthermore, the framing effect does not differentially affect the attitudes of high-NFC individuals with high knowledge. In contrast, low-NFC individuals with low knowledge hold more favorable attitudes toward positively framed messages than negatively framed messages.
19. COMPARING FRAMES, FRAMING COMPARISONS: GREECE/EU FRAMES ON GENDER INEQUALITY IN POLITICS
OpenAIRE
Maloutas, Maro Pantelidou
2016-01-01
This article intends to present the main similarities and differences between Greece and the EU in respect to the framing of gender inequality in political decision making as a policy issue, based on the ways that the problem is diagnosed. It also aims at the formulation of a hypothesis which argues that beyond the above similarities and differences, which may tint in a different colour measures and policies showing one case more gender sensitive or more «traditional» than the other, there ex...
20. Frames, operator representations, and open problems
DEFF Research Database (Denmark)
Christensen, Ole; Hasannasab, Marzieh
2018-01-01
, a topic that has recently attracted considerably interest within harmonic analysis. The goal of the paper is twofold, namely, that experts in operator theory will explore the potential of frames, and that frame theory will benefit from insight provided by the operator theory community.......A frame in a Hilbert space H is a countable collection of elements in H that allows each f ϵ H to be expanded as an (infinite) linear combination of the frame elements. Frames generalize the wellknown orthonormal bases, but provide much more exibility and can often be constructed with properties...... that are not possible for orthonormal bases. We will present the basic facts in frame theory with focus on their operator theoretical characterizations and discuss open problems concerning representations of frames in terms of iterations of a fixed operator. These problems come up in the context of dynamical sampling... | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6032195687294006, "perplexity": 2933.5009251635506}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-34/segments/1534221215176.72/warc/CC-MAIN-20180819125734-20180819145734-00298.warc.gz"} |
https://astarmathsandphysics.com/a-level-maths-notes/s1/4454-exoected-time-to-get-facebook-likes.html | ## Exoected Time to Get Facebook Likes
Most people, when they visit most Facebook pages, are not very interested. They don't find much reason to either like or dislike the page. Given however, that a page can either be liked or disliked, how long will it be before a certain number of likes,
$N$
is reached?
Suppose that a page has
$n$
visitors per day. The probability of a person liking the page is
$p$
and the probability of someone disliking it is
$p$
. Suppose also that these two probabilities are independent. The expect number of likes in a day is
$np$
and the expected number of dislikes in
$nq$
. The expected number of net likes is
$np-nq=n(p-q)$
The in will be an estimated
$\frac{N}{n(p-q)}$
days before you get
$N$
$q \gt p$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6602845191955566, "perplexity": 1305.7867979828395}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-17/segments/1524125949489.63/warc/CC-MAIN-20180427060505-20180427080505-00013.warc.gz"} |
https://www.arxiv-vanity.com/papers/adap-org/9609001/ | arXiv Vanity renders academic papers from arXiv as responsive web pages so you don’t have to squint at a PDF. Read this paper on arXiv.org.
# Ecological model of extinctions
Guillermo Abramson 1 International Centre for Theoretical Physics,
PO Box 586, 34100 Trieste, Italy
11E-mail:
April 13, 2020
###### Abstract
We present numerical results based on a simplified ecological system in evolution, showing features of extinction similar to that claimed for the biosystem on Earth. In the model each species consists of a population in interaction with the others, that reproduces and evolves in time. Each species is simultaneously a predator and a prey in a food chain. Mutations that change the interactions are supposed to occur randomly at a low rate. Extinctions of populations result naturally from the predator-prey dynamics. The model is not pinned in a fitness variable, and natural selection arises from the dynamics.
###### pacs:
87.10.+e, 05.40.+j, 05.45.+b
## I Introduction
The evolution of living organisms is a fascinating phenomenon that has intrigued the imagination of the scientific and non-scientific community. However, the formulation of mathematical models falls necessarily to drastic simplifications. For example, evolution has often been considered as a “walk” in a rugged landscape. Following this line, Bak and Sneppen (BS) have proposed a model of biological evolution [1] that has become quite interesting to the physics community due to its simplicity and the new insight it provides to the problem. It has been shown that this model evolves to a self-organized critical state (SOC), and is kept there by the means of avalanches of evolutionary activity. This is appealing for a model of biological evolution, since it has been observed that life on Earth could be in a SOC state [2, 3]. Nevertheless, models based in fitness landscapes, or in a concept of fitness different from the biological one, have been criticized from a biological point of view [3, 4].
Since one of the characterizing aspects of life, and perhaps the most fundamental one, is that of self-replication, it is our belief that more realistic models should involve a dynamic population for each species. The starting point of combining population dynamics with evolution is the association of the rates of birth and death and the carrying capacity with phenotypes (observable features that arise from the genotype and are, then, subject to mutation) [5]. The fitness, namely the expected number of offsprings produced by an individual, arise from them. In this way, the process of natural selection is directed by the ecological interactions instead of by a non-biological notion of relative fitness.
Extinction is an essential component of evolution. The great majority of species that have ever lived on Earth are now extinct[6]. There exist competing hypothesis that account extinction as originating from within the biosystem, or from external causes –what has been called “bad genes or bad luck”. In any case, the pattern of extinctions and of surviving species or groups of species is certainly an interesting problem to model, to understand, and eventually to check with the fossil record.
We show in this contribution a simple model of a large ecological system in evolution. This produces features of extinction similar to those claimed for the biosystem on Earth. We have chosen to study an ecological model in which each species consists of a population interacting with the others, that reproduces and evolves in time. The system is supposed to be a food chain, and the interactions to be predator-prey. Mutations that change the interactions are supposed to occur randomly at a low rate. Extinctions of populations result from the predator-prey dynamics. This approach can be thought as middle way between the microscopic simulation of “artificial life” by Ray and others [7], and the coarse-grain description of models like BS’s.
## Ii The model
Our model ecosystem consists of a number of species that interact and evolve in time. In the course of its time evolution the populations grow and shrink following a set of equations. Eventually, some of the species become extinct as a result of their interaction with the others. Every now and then we change one of the phenotypic features of one of the species, mimicking a random mutation of its genome. This modification produces a perturbation in the dynamics of the ecosystem, and eventually leads to the extinctions.
To be more precise, let’s consider a simple example of a food web, namely a one-dimensional food chain. species interact in such a way that the species feeds on the species , and is eaten by the species . The species is an autotroph: it feeds at a constant rate on an “environment”. The species , the top of the chain, is not eaten by any species, but dies giving its mass to the environment. Each species has a population that evolves in time and interacts with its neighbors in the chain. Furthermore, we consider this evolution in discrete time, which is often more realistic than a continuous one [5] and simpler to simulate in a computer.
As has been said above, each species acts as a predator with respect to the one preceding it in the chain, and as a prey with respect to the one following it. As a further simplification, we suppose that there are no intrinsic birth and death rates, apart from those arising from the predation and prey contributions. Let’s propose the equations governing this behaviors [8]. As a predator, the “population” (a continuous density) of the species , , changes from time to time according to:
Δnit=kini−1tnit(1−nit/ci), (1)
where is a rate of growth of the predator population and is a carrying capacity that accounts for a limitation imposed by the environment. Note that (1) includes this carrying capacity in a logistic factor to avoid an unbounded growth of the population. Also observe that the growth is proportional to the population of preys, without a “satiation” factor. Similarly, as a prey, the population of the species will diminish according to:
Δnit=−ginitni+1t. (2)
The parameters , and are the phenotypic features of our species. In the course of the evolution we allow them to change, mimicking random mutations. Moreover, they are the same for all the individuals of each single population. We do not model races, traits, polymorphisms or any phenotypic variation within a species, and when a mutation occurs it is assumed that the whole population “moves” instantly to the new state. In this sense, we are modelling the co-evolution of the species and disregarding the evolution of a single one as well as other important phenomena like the formation of new species [9].
Combining the two roles of predator and prey that each species performs, and the special status of the ends of the chain, we can write the following set of equations for the evolution of the system:
{Δnit=kini−1tnit(1−nit/ci)−gini+1tnit\ \ \ \ for i=1…Nn0=nN+1=1, (3)
where we have introduced two fictitious species, and , to take account for the border condition.
We make two simplifications to the system (3): 1) we assume that all the carrying capacities are equal, and equal to ; 2) we assume that . In this way we reduce the number of parameters that define the phenotypic features of the ecosystem.
The dynamics of the system is as follows. At time , all the populations and interactions are chosen at random with uniform distribution in the interval . Then the populations begin to evolve according to the system (3). In the course of the evolution driven by eq.(3) a population can go to zero. As this can happen asymptotically, we consider a species extinct if its population drops below a given threshold. This is reasonable since actual biological populations are discrete. In order to keep constant the number of species we replace an extinct one with a new one, which can be thought as a species coming to occupy the niche left by the extinct one [10]. The new population, and the (two) new interactions with its neighbors in the chain, are also drawn at random from a uniform distribution in the interval . On top of this dynamics of predation and extinctions, we introduce random mutations. In each time step a mutation is produced with probability ; the species to mutate is chosen at random and the mutation itself consists of the replacement of the species with a new one, with a new population and new interactions with its predators and preys (all random in ).
Observe that we do not introduce the fitness of a species as a dynamical variable. We do not even need to compute it from the “phenotypes” . The fitness, the degree of adaptation of a species to the ecosystem, arises from the phenotypes, the populations, and the dynamics, and it determines whether a species will thrive or become extinct. Chance is introduced by the random mutations (and the random replacement of extinct species). It provides the material the natural selection works on. This, in turn, determines the survival of the fittest by simply eliminating from the system those species that cannot cope with the competing environment. We believe in this way we avoid a fundamental problem in the models of evolution as a walk in a fitness landscape, namely that the concepts of fitness is not the biological one [4].
## Iii Results of the numerical simulation
We have run our model for several chain sizes, ranging from to sites, and for times of about steps. In the results reported below we let the system evolve, during a transient period, from the initial random state to an organized one.
In fig. 1 we show a typical evolution of the whole population, . Although each population greatly changes in the course of time (what is not shown in the picture), we observe that the whole population remains relatively stable. This is due to the saturation factor in the predation term of the evolution equations. This whole population shows a short time oscillatory dynamics governed by the competition between species through the set of equations (3), and a long time evolution characterized by periods of relative stasis and periods of fast change. This feature is the effect of mutations and extinction of some species. Without the extinctions and mutations, the dynamics of the system should probably be chaotic. But it is not this feature that we want to analyze here. Instead, we shall focus on the pattern of extinctions.
As the set of represents the phenotypes of the whole ecosystem, its distribution, , can be used to characterize its state. Let’s observe what happens in the course of time, including the transient mentioned above. Initially the are chosen at random, and thus its distribution is flat in , with mean . This is shown in fig. 2 as a full line. As time passes, and as a result of the dynamics, this distribution shifts to a non-uniform one, as shown in fig. 2 with dashed lines. The whole distribution shifts towards lower values of the interaction, showing a tendency of the system to reduce the coupling between the species. In the course of the evolution this distribution fluctuates following the pattern of mutations and extinctions, but preserves its form.
Fig. 3 shows the above mentioned fluctuations in as the evolution of the mean value of in the system, after the transient. It corresponds to the same run as fig. 1, and the same time window is shown. Similarly to that, it displays a pattern of periods of stasis interrupted by periods of fast change, but without the short time oscillations displayed by the population. There are periods of stasis of all lengths, to a degree that the unique scale of the figure cannot display. This feature of a lack of a typical length will be analyzed immediately. Observe in this figure that the mean value oscillates around , corresponding to a distribution like that shown in fig. 2 with a dotted line.
The extinction events also display this characteristic pattern of periods of stasis and periods of change, without a typical size. In order to characterize this, we have chosen the time between two consecutive extinction events, , which distribution is shown in fig. 4 for several system sizes an probabilities of mutation. Observe that they follow a power law for several decades of large values of , before a region where the effects of the finite size of the system start to appear. This is a sign that the system has self-organized into a critical state. In other words, the extinction events are distributed in the time axis in such a way that the time between extinctions does not have a characteristic duration –as should have if the distribution were exponential. Extinctions appear to come in bursts, or avalanches, of any size.
In fig. 5 the pattern of extinction events of the system is seen in the course of time. The graphic displays time in the abscissa and the index in the food chain in the ordinate. Each dot marks the moment in which a species has become extinct. Each cross, a species that suffers a chance mutation. It can be seen that some mutations trigger avalanches of extinction, and that these propagate in the “prey” direction. (Bear in mind that an extinct species is replaced by a random new one, most probably with a larger population than its predecessor, and observe that this has a negative impact in the corresponding prey.) It is also apparent that this avalanches have a complex shape in space-time. It is not easy to measure their size since, as can be seen in fig. 5, they overlap. See, for example, a mutation that is not followed by any avalanche (lower left), another that triggers a very small one (lower right), and several that start events of varying size. In any case, let’s define a time step, , divide the time axis with it, and count the number of extinctions in each interval. Now, let’s call the fraction of species that have become extinct in each interval the size, , of the extinction. will obviously depend on the time step and on the size of the system: . If the system is in a critical state this function will obey some scaling law on the variable . In fig. 6 we have scaled the distribution of the system size , , obtained for different system sizes according to the ansatz:
P(S,N)=Nβf(S⋅Nν). (4)
We can observe that the four curves collapse to a single one, showing the scaling behaviour that is typical of a critical state.
## Iv Conclusions
We have introduced a simple model of co-evolution and extinction in a food chain. This consists of a finite chain of species of predators and preys. Their populations evolve in time following Lotka-Volterra-like equations. Evolution is mimicked by randomly changing a phenotype. Natural selection is provided by the deterministic behaviour of the dynamical system, that produces the extinction of any species that cannot cope with its interactions. No relative fitness or fitness landscape had to be invoked. Nevertheless, the pattern of extinctions displayed by this toy ecosystem appears to be similar to that proposed for the biosystem on Earth. Namely, the system seems to be in a critical state, in which extinctions occur in avalanches. The time between extinctions, and the lifetime of any species follow distributions that behave like power-laws of time, implying that there is no typical size for the time that a species remains in the system. I should be of interest, in a future work, to study the precise instability that produces the shift of the distribution of the interactions towards low values. The analytical treatment of this problem is currently under study.
The author greatly acknowledges Ruben Weht for invaluable discussions, and thank Hilda Cerdeira for a careful reading of the manuscript.
## References
• [1] (a) P. Bak and K. Sneppen, Phys. Rev. Lett. 71, 4083 (1993); (b) M. Paczuski, S. Maslov and P. Bak, Phys. Rev. E 53, 414 (1996). Many extensions and modifications have been proposed to the original BS model; see, for example, (c) B.J. Roberts and M.E.J. Newman, J. Theor. Biol. 180, 39 (1996).
• [2] S.A. Kauffman and S. Johnsen, J. Theor. Biol. 149, 467 (1991).
• [3] M.E.J. Newman, Los Alamos National Laboratory preprint adap-org/9607002 (1996).
• [4] T.B. Jongeling, J. Theor. Biol. 178, 369 (1996).
• [5] J. Roughgarden, Theory of Population Genetics and Evolutionary Ecology An Introduction, (Macmillan Pub. Co., New York, 1979).
• [6] D.M. Raup, Science 231, 1528 (1986).
• [7] (a) T.S. Ray, Physica D 75, 239 (1994). This is actually a brief account of Ray’s previous work on “artificial life”. (b) C.Adami, Physics Letters A 203, 29 (1995).
• [8] J.D. Murray, Mathematical Biology, 2nd edition, (Springer-Verlag, Berlin, 1993).
• [9] Up to our knowledge, N. Vandewalle and M. Ausloos, Physica D 90, 262 (1996) is the only model that incorporates speciation into a model like BS’s.
• [10] If the number of species should not be kept constant, another assumption should be made to somehow fill the hole in the chain so it doesn’t break in two with each extinction. For example, the prey and the predator of the extinct species could become mutual prey and predator, with a new interaction constant; but we think that the replacement of the niche with a new species is biologically more relevant.
Want to hear about new tools we're making? Sign up to our mailing list for occasional updates. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8242281079292297, "perplexity": 660.951525340249}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-45/segments/1603107877420.17/warc/CC-MAIN-20201021180646-20201021210646-00083.warc.gz"} |
http://r-pkgs.had.co.nz/man.html | # Object documentation
Documentation is one of the most important aspects of a good package. Without it, users won’t know how to use your package. Documentation is also useful for future-you (so you remember what your functions were supposed to do), and for developers extending your package.
There are multiple forms of documentation. In this chapter, you’ll learn about object documentation, as accessed by ? or help(). Object documentation is a type of reference documentation. It works like a dictionary: while a dictionary is helpful if you want to know what a word means, it won’t help you find the right word for a new situation. Similarly, object documentation is helpful if you already know the name of the object, but it doesn’t help you find the object you need to solve a given problem. That’s one of the jobs of vignettes, which you’ll learn about in the next chapter.
R provides a standard way of documenting the objects in a package: you write .Rd files in the man/ directory. These files use a custom syntax, loosely based on LaTeX, and are rendered to HTML, plain text and pdf for viewing. Instead of writing these files by hand, we’re going to use roxygen2 which turns specially formatted comments into .Rd files. The goal of roxygen2 is to make documenting your code as easy as possible. It has a number of advantages over writing .Rd files by hand:
• Code and documentation are intermingled so that when you modify your code, you’re reminded to also update your documentation.
• Roxygen2 dynamically inspects the objects that it documents, so you can skip some boilerplate that you’d otherwise need to write by hand.
• It abstracts over the differences in documenting different types of objects, so you need to learn fewer details.
As well as generating .Rd files, roxygen2 can also manage your NAMESPACE and the Collate field in DESCRIPTION. This chapter discusses .Rd files and the collate field. NAMESPACE describes how you can use roxygen2 to manage your NAMESPACE, and why you should care.
## The documentation workflow
In this section, we’ll first go over a rough outline of the complete documentation workflow. Then, we’ll dive into each step individually. There are four basic steps:
2. Run devtools::document() (or press Ctrl/Cmd + Shift + D in RStudio) to convert roxygen comments to .Rd files. (devtools::document() calls roxygen2::roxygenise() to do the hard work.)
3. Preview documentation with ?.
4. Rinse and repeat until the documentation looks the way you want.
#'
#' @param x A number.
#' @param y A number.
#' @return The sum of \code{x} and \code{y}.
#' @examples
x + y
}
Pressing Ctrl/Cmd + Shift + D (or running devtools::document()) will generate a man/add.Rd that looks like:
% Generated by roxygen2 (4.0.0): do not edit by hand
\usage{
}
\arguments{
\item{x}{A number}
\item{y}{A number}
}
\value{
The sum of \code{x} and \code{y}
}
\description{
}
\examples{
}
If you’re familiar with LaTeX, this should look familiar since the .Rd format is loosely based on it. You can read more about the Rd format in the R extensions manual. Note the comment at the top of the file: it was generated by code and shouldn’t be modified. Indeed, if you use roxygen2, you’ll rarely need to look at these files.
When you use ?add, help("add"), or example("add"), R looks for an .Rd file containing \alias{"add"}. It then parses the file, converts it into HTML and displays it. Here’s what the result looks like in RStudio:
(Note you can preview development documentation because devtools overrides the usual help functions to teach them how to work with source packages. If the documentation doesn’t appear, make sure that you’re using devtools and that you’ve loaded the package with devtools::load_all().)
## Alternative documentation workflow
The first documentation workflow is very fast, but it has one limitation: the preview documentation pages will not show any links between pages. If you’d like to also see links, use this workflow:
2. Click in the build pane or press Ctrl/Cmd + Shift + B. This completely rebuilds the package, including updating all the documentation, installs it in your regular library, then restarts R and reloads your package. This is slow but thorough.
3. Preview documentation with ?.
4. Rinse and repeat until the documentation looks the way you want.
If this workflow doesn’t seem to be working, check your project options in RStudio. Old versions of devtools and RStudio did not automatically update the documentation when the package was rebuilt:
Roxygen comments start with #' and come before a function. All the roxygen lines preceding a function are called a block. Each line should be wrapped in the same way as your code, normally at 80 characters.
Blocks are broken up into tags, which look like @tagName details. The content of a tag extends from the end of the tag name to the start of the next tag (or the end of the block). Because @ has a special meaning in roxygen, you need to write @@ if you want to add a literal @ to the documentation (this is mostly important for email addresses and for accessing slots of S4 objects).
Each block includes some text before the first tag.1 This is called the introduction, and is parsed specially:
• The first sentence becomes the title of the documentation. That’s what you see when you look at help(package = mypackage) and is shown at the top of each help file. It should fit on one line, be written in sentence case, and end in a full stop.
• The second paragraph is the description: this comes first in the documentation and should briefly describe what the function does.
• The third and subsequent paragraphs go into the details: this is a (often long) section that is shown after the argument description and should go into detail about how the function works.
All objects must have a title and description. Details are optional.
Here’s an example showing what the introduction for sum() might look like if it had been written with roxygen:
#' Sum of vector elements.
#'
#' \code{sum} returns the sum of all the values present in its arguments.
#'
#' This is a generic function: methods can be defined for it directly or via the
#' \code{\link{Summary}} group generic. For this to work properly, the arguments
#' \code{...} should be unnamed, and dispatch is on the first argument.
sum <- function(..., na.rm = TRUE) {}
\code{} and \link{} are formatting commands that you’ll learn about in formatting. I’ve been careful to wrap the roxygen block so that it’s less than 80 characters wide. You can do that automatically in Rstudio with Ctrl/Cmd + Shift + / (or from the menu, code | re-flow comment).
You can add arbitrary sections to the documentation with the @section tag. This is a useful way of breaking a long details section into multiple chunks with useful headings. Section titles should be in sentence case, must be followed by a colon, and they can only be one line long.
#' @section Warning:
#' Do not operate heavy machinery within 8 hours of using this function.
There are two tags that make it easier for people to navigate between help files:
• @seealso allows you to point to other useful resources, either on the web, \url{http://www.r-project.org}, in your package \code{\link{functioname}}, or another package \code{\link[packagename]{functioname}}.
• If you have a family of related functions where every function should link to every other function in the family, use @family. The value of @family should be plural.
For sum, these components might look like:
#' @family aggregate functions
#' high-dimensional arrays.
Two other tags make it easier for the user to find documentation:
• @aliases alias1 alias2 ... adds additional aliases to the topic. An alias is another name for the topic that can be used with ?.
• @keywords keyword1 keyword2 ... adds standardised keywords. Keywords are optional, but if present, must be taken from a predefined list found in file.path(R.home("doc"), "KEYWORDS").
Generally, keywords are not that useful except for @keywords internal. Using the internal keyword removes the function from the package index and disables some of their automated tests. It’s common to use @keywords internal for functions that are of interest to other developers extending your package, but not most users.
Other tags are situational: they vary based on the type of object that you’re documenting. The following sections describe the most commonly used tags for functions, packages and the various methods, generics and objects used by R’s three OO systems.
## Documenting functions
Functions are the most commonly documented object. As well as the introduction block, most functions have three tags: @param, @examples and @return.
• @param name description describes the function’s inputs or parameters. The description should provide a succinct summary of the type of the parameter (e.g., string, numeric vector) and, if not obvious from the name, what the parameter does.
The description should start with a capital letter and end with a full stop. It can span multiple lines (or even paragraphs) if necessary. All parameters must be documented.
You can document multiple arguments in one place by separating the names with commas (no spaces). For example, to document both x and y, you can write @param x,y Numeric vectors..
• @examples provides executable R code showing how to use the function in practice. This is a very important part of the documentation because many people look at the examples first. Example code must work without errors as it is run automatically as part of R CMD check.
For the purpose of illustration, it’s often useful to include code that causes an error. \dontrun{} allows you to include code in the example that is not run. (You used to be able to use \donttest{} for a similar purpose, but it’s no longer recommended because it actually is tested.)
Instead of including examples directly in the documentation, you can put them in separate files and use @example path/relative/to/packge/root to insert them into the documentation.
• @return description describes the output from the function. This is not always necessary, but is a good idea if your function returns different types of output depending on the input, or if you’re returning an S3, S4 or RC object.
We could use these new tags to improve our documentation of sum() as follows:
#' Sum of vector elements.
#'
#' \code{sum} returns the sum of all the values present in its arguments.
#'
#' This is a generic function: methods can be defined for it directly
#' or via the \code{\link{Summary}} group generic. For this to work properly,
#' the arguments \code{...} should be unnamed, and dispatch is on the
#' first argument.
#'
#' @param ... Numeric, complex, or logical vectors.
#' @param na.rm A logical scalar. Should missing values (including NaN)
#' be removed?
#' @return If all inputs are integer and logical, then the output
#' will be an integer. If integer overflow
#' \url{http://en.wikipedia.org/wiki/Integer_overflow} occurs, the output
#' will be NA with a warning. Otherwise it will be a length-one numeric or
#' complex vector.
#'
#' Zero-length vectors have sum 0 by definition. See
#' \url{http://en.wikipedia.org/wiki/Empty_sum} for more details.
#' @examples
#' sum(1:10)
#' sum(1:5, 6:10)
#' sum(F, F, F, T, T)
#'
#' sum(.Machine$integer.max, 1L) #' sum(.Machine$integer.max, 1)
#'
#' \dontrun{
#' sum("a")
#' }
sum <- function(..., na.rm = TRUE) {}
Indent the second and subsequent lines of a tag so that when scanning the documentation it’s easy to see where one tag ends and the next begins. Tags that always span multiple lines (like @example) should start on a new line and don’t need to be indented.
## Documenting datasets
See documenting data.
## Documenting packages
You can use roxygen to provide a help page for your package as a whole. This is accessed with package?foo, and can be used to describe the most important components of your package. It’s a useful supplement to vignettes, as described in the next chapter.
There’s no object that corresponds to a package, so you need to document NULL, and then manually label it with @docType package and @name <package-name>. This is also an excellent place to use the @section tag to divide up page into useful categories.
#' foo: A package for computating the notorious bar statistic.
#'
#' The foo package provides three categories of important functions:
#' foo, bar and baz.
#'
#' @section Foo functions:
#' The foo functions ...
#'
#' @docType package
#' @name foo
NULL
#> NULL
I usually put this documentation in a file called <package-name>.R. It’s also a good place to put the package level import statements that you’ll learn about in imports.
## Documenting classes, generics and methods
It’s relatively straightforward to document classes, generics and methods. The details vary based on the object system you’re using. The following sections give the details for the S3, S4 and RC object systems.
### S3
S3 generics are regular functions, so document them as such. S3 classes have no formal definition, so document the constructor function. It is your choice whether or not to document S3 methods. You don’t need to document methods for simple generics like print(). But if your method is more complicated or includes additional arguments, you should document it so people know how it works. In base R, you can see examples of documentation for more complex methods like predict.lm(), predict.glm(), and anova.glm().
Older versions of roxygen required explicit @method generic class tags for all S3 methods. From version 3.0.0 onward, this is no longer needed as roxygen2 will figure it out automatically. If you are upgrading, make sure to remove these old tags. Automatic method detection will only fail if the generic and class are ambiguous. For example is all.equal.data.frame() the equal.data.frame method for all, or the data.frame method for all.equal?. If this happens, you can disambiguate with e.g. @method all.equal data.frame.
### S4
Document S4 classes by adding a roxygen block before setClass(). Use @slot to document the slots of the class in the same way you use @param to describe the parameters of a function. Here’s a simple example:
#' An S4 class to represent a bank account.
#'
#' @slot balance A length-one numeric vector
Account <- setClass("Account",
slots = list(balance = "numeric")
)
S4 generics are also functions, so document them as such. S4 methods are a little more complicated, however. Unlike S3, all S4 methods must be documented. You document them like a regular function, but you probably don’t want each method to have its own documentation page. Instead, put the method documentation in one of three places:
• In the class. Most appropriate if the corresponding generic uses single dispatch and you created the class.
• In the generic. Most appropriate if the generic uses multiple dispatch and you have written both the generic and the method.
• In its own file. Most appropriate if the method is complex, or if you’ve written the method but not the class or generic.
Use either @rdname or @describeIn to control where method documentation goes. See documenting multiple objects in one file for details.
Another consideration is that S4 code often needs to run in a certain order. For example, to define the method setMethod("foo", c("bar", "baz"), ...) you must already have created the foo generic and the two classes. By default, R code is loaded in alphabetical order, but that won’t always work for your situation. Rather than relying on alphabetic ordering, roxygen2 provides an explicit way of saying that one file must be loaded before another: @include. The @include tag gives a space separated list of file names that should be loaded before the current file:
#' @include class-a.R
setClass("B", contains = "A")
Often, it’s easiest to put this at the top of the file. To make it clear that this tag applies to the whole file, and not a specific object, document NULL.
#' @include foo.R bar.R baz.R
NULL
setMethod("foo", c("bar", "baz"), ...)
Roxygen uses the @include tags to compute a topological sort which ensures that dependencies are loaded before they’re needed. It then sets the Collate field in DESCRIPTION, which overrides the default alphabetic ordering. A simpler alternative to @include is to define all classes and methods in aaa-classes.R and aaa-generics.R, and rely on these coming first since they’re in alphabetical order. The main disadvantage is that you can’t organise components into files as naturally as you might want.
Older versions of roxygen2 required explicit @usage, @alias and @docType tags for document S4 objects. However, as of version 3.0.0, roxygen2 generates the correct values automatically so you no longer need to use them. If you’re upgrading from an old version, you can delete these tags.
### RC
Reference classes are different to S3 and S4 because methods are associated with classes, not generics. RC also has a special convention for documenting methods: the docstring. The docstring is a string placed inside the definition of the method which briefly describes what it does. This makes documenting RC simpler than S4 because you only need one roxygen block per class.
#' A Reference Class to represent a bank account.
#'
#' @field balance A length-one numeric vector.
Account <- setRefClass("Account",
fields = list(balance = "numeric"),
methods = list(
withdraw = function(x) {
"Withdraw money from account. Allows overdrafts"
balance <<- balance - x
}
)
)
Methods with doc strings will be included in the “Methods” section of the class documentation. Each documented method will be listed with an automatically generated usage statement and its doc string. Also note the use of @field instead of @slot.
## Special characters
There are three special characters that need special handling if you want them to appear in the final documentation:
• @, which usually marks the start of a roxygen tag. Use @@ to insert a literal @ in the final documentation.
• %, which usually marks the start of a latex comment which continues to the end of the line. Use \% to insert a literal % in the output document. The escape is not needed in examples.
• \, which usually marks the start of a latex escaping. Use \\ to insert a literal \ in the documentation.
## Do repeat yourself
There is a tension between the DRY (don’t repeat yourself) principle of programming and the need for documentation to be self-contained. It’s frustrating to have to navigate through multiple help files in order to pull together all the pieces you need. Roxygen2 provides two ways to avoid repetition in the source, while still assembling everything into one documentation file:
• The ability to reuse parameter documentation with @inheritParams.
• The ability to document multiple functions in the same place with @describeIn or @rdname
### Inheriting parameters from other functions
You can inherit parameter descriptions from other functions using @inheritParams source_function. This tag will bring in all documentation for parameters that are undocumented in the current function, but documented in the source function. The source can be a function in the current package, via @inheritParams function, or another package, via @inheritParams package::function. For example the following documentation:
#' @param a This is the first argument
foo <- function(a) a + 10
#' @param b This is the second argument
#' @inheritParams foo
bar <- function(a, b) {
foo(a) * 10
}
is equivalent to
#' @param a This is the first argument
#' @param b This is the second argument
bar <- function(a, b) {
foo(a) * 10
}
Note that inheritance does not chain. In other words, the source_function must always be the function that defines the parameter using @param.
### Documenting multiple functions in the same file
You can document multiple functions in the same file by using either @rdname or @describeIn. However, it’s a technique best used with caution: documenting too many functions in one place leads to confusing documentation. You should use it when functions have very similar arguments, or have complementary effects (e.g., open() and close() methods).
@describeIn is designed for the most common cases:
• Documenting methods in a generic.
• Documenting methods in a class.
• Documenting functions with the same (or similar arguments).
It generates a new section, named either “Methods (by class)”, “Methods (by generic)” or “Functions”. The section contains a bulleted list describing each function. They’re labelled so that you know what function or method it’s talking about. Here’s an example, documenting an imaginary new generic:
#' Foo bar generic
#'
#' @param x Object to foo.
foobar <- function(x) UseMethod("foobar")
#' @describeIn foobar Difference between the mean and the median
foobar.numeric <- function(x) abs(mean(x) - median(x))
#' @describeIn foobar First and last values pasted together in a string.
foobar.character <- function(x) paste0(x[1], "-", x[length(x)])
An alternative to @describeIn is @rdname. It overrides the default file name generated by roxygen and merges documentation for multiple objects into one file. This gives you the complete freedom to combine documentation as you see fit.
There are two ways to use @rdname. You can add documentation to an existing function:
#' Basic arithmetic
#'
#' @param x,y numeric vectors.
add <- function(x, y) x + y
times <- function(x, y) x * y
Or, you can create a dummy documentation file by documenting NULL and setting an informative @name.
#' Basic arithmetic
#'
#' @param x,y numeric vectors.
#' @name arith
NULL
#> NULL
#' @rdname arith
add <- function(x, y) x + y
#' @rdname arith
times <- function(x, y) x * y
## Text formatting reference sheet
Within roxygen tags, you use .Rd syntax to format text. This vignette shows you examples of the most important commands. The full details are described in R extensions.
Note that \ and % are special characters in the Rd format. To insert a literal % or \, escape them with a backslash \\, \%.
### Character formatting
• \emph{italics}: italics.
• \strong{bold}: bold.
• \code{r_function_call(with = "arguments")}: r_function_call(with = "arguments") (format inline code)
• \preformatted{}: format text as-is, can be used for multi-line code
To other documentation:
• \code{\link{function}}: function in this package.
• \code{\link[MASS]{abbey}}: function in another package.
To the web:
• \url{http://rstudio.com}: a url.
• \href{http://rstudio.com}{Rstudio}:, a url with custom link text.
### Lists
• Ordered (numbered) lists:
#' \enumerate{
#' \item First item
#' \item Second item
#' }
• Unordered (bulleted) lists:
#' \itemize{
#' \item First item
#' \item Second item
#' }
• Definition (named) lists:
#' \describe{
#' \item{One}{First item}
#' \item{Two}{Second item}
#' }
### Mathematics
You can use standard LaTeX math (with no extensions). Choose between either inline or block display:
• \eqn{a + b}: inline equation.
• \deqn{a + b}: display (block) equation.
### Tables
Tables are created with \tabular{}. It has two arguments:
1. Column alignment, specified by letter for each column (l = left, r = right, c = centre.)
2. Table contents, with columns separated by \tab and rows by \cr.
The following function turns an R data frame into the correct format. It ignores column and row names, but should get you started.
tabular <- function(df, ...) {
stopifnot(is.data.frame(df))
align <- function(x) if (is.numeric(x)) "r" else "l"
col_align <- vapply(df, align, character(1))
cols <- lapply(df, format, ...)
contents <- do.call("paste",
c(cols, list(sep = " \\tab ", collapse = "\\cr\n ")))
paste("\\tabular{", paste(col_align, collapse = ""), "}{\n ",
contents, "\n}\n", sep = "")
}
cat(tabular(mtcars[1:5, 1:5]))
#> \tabular{rrrrr}{
#> 21.0 \tab 6 \tab 160 \tab 110 \tab 3.90\cr
#> 21.0 \tab 6 \tab 160 \tab 110 \tab 3.90\cr
#> 22.8 \tab 4 \tab 108 \tab 93 \tab 3.85\cr
#> 21.4 \tab 6 \tab 258 \tab 110 \tab 3.08\cr
#> 18.7 \tab 8 \tab 360 \tab 175 \tab 3.15
#> }
### Notes
1. Note that it is possible to define the “introduction” sections - the title and description - explicitly, rather than implicitly, using @title and @description tags. I follow the convention of avoiding this, as do many other package authors, so I don’t recommend it - but you should be aware that these tags do exist and may appear in other package-writers’ source code. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.45061880350112915, "perplexity": 3520.392138215247}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-40/segments/1443737904854.54/warc/CC-MAIN-20151001221824-00092-ip-10-137-6-227.ec2.internal.warc.gz"} |
http://www.numeric-gmbh.ch/posts/investigating-excessive-pivot-ratios-in-matrix-kll-12.html | # Investigating “excessive PIVOT RATIOS IN MATRIX KLL” (1/2)
Published: jeu. 11 septembre 2014
## Introduction
A common issue for NASTRAN models is the famous ”USER FATAL MESSAGE 9137 (SEKRRS)”. The experience described below clearly shows that this message can be due not only to lack of attachment, but also due to an excessive stiffness differential between model and attachments.
USER FATAL MESSAGE 9137 (SEKRRS)
RUN TERMINATED DUE TO EXCESSIVE PIVOT RATIOS IN MATRIX KLL.
USER ACTION: CONSTRAIN MECHANISMS WITH SPCI OR SUPORTI ENTRIES OR SPECIFY PARAM,BAILOUT,-1 TO
CONTINUE THE RUN WITH MECHANISMS.
## First direction to follow
The first direction to follow is the one provided by NASTRAN itself:
constrain mechanisms with spci or suport entries or specify PARAM,BAILOUT,-1 to continue the run with mechanisms.
The user can now add the PARAM, BAILOUT, -1 and run again the analysis, or run a modal analysis (a conveniant shortcut exists via FEMAP command Custom Tools>>Standard Analysis>>modal analysis).
## Running a Modal Analysis
Running a modal Analysis may be more convenient than running Mechanisms (PARAM, BAILOUT, -1) due to the rich information provided by first modes frequencies. In the example used here, the lowest mode is 1.055 Hz. If the model had been poorly constrained (aka. not enough constrained), many of the first modes are below 0.01Hz.
This first investigation shows that model is correctly constrained.
## Running the Mechanism Mode
Running the mechanism mode using PARAM, BAILOUT, -1 do not show additional information, and shows normal deformation and stresses. One more time, if the model would have been poorly constrained, mechanism would have shown it immediately.
So What?
Second part of this post to be read here. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6396631598472595, "perplexity": 4627.413657324248}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-09/segments/1550247481766.50/warc/CC-MAIN-20190217071448-20190217093448-00607.warc.gz"} |
http://mathonline.wikidot.com/egoroff-s-theorem | Egoroff's Theorem
# Egoroff's Theorem
Recall from the Littlewood's First Principle page that Littlewood's first principle says that if $E$ is a Lebesgue measurable set with $m(E) < \infty$ then for all $\epsilon > 0$ there exists a finite collection of open intervals $\{ I_1, I_2, ..., I_N \}$ such that:
(1)
\begin{align} \quad m \left ( E \Delta \bigcup_{n=1}^{N} I_n \right ) < \epsilon \end{align}
In other words, a Lebesgue measurable set $E$ with finite measure can be covered almost entirely by a finite union of open intervals.
We will now prove another very important theorem known as Egoroff's theorem which is stated below.
Theorem 1 (Egoroff's Theorem): Let $E$ be a Lebesgue measurable set with $m(E) < \infty$. If $(f_n(x))_{n=1}^{\infty}$ is a sequence of Lebesgue measurable functions that converges pointwise to a function $f(x)$ on $E$ then for all $\epsilon > 0$ there exists a closed set $F \subseteq E$ such that: 1) $m(E \setminus F) < \epsilon$. 2) $(f_n(x))_{n=1}^{\infty}$ converges to $f(x)$ uniformly on $F$.
• Proof: Let $E$ be a Lebesgue measurable set with $m(E) < \infty$ and let $(f_n(x))_{n=1}^{\infty}$ be a sequence of Lebesgue measurable functions on $E$ that converge pointwise to $f(x)$ on $E$.
• Let $\epsilon > 0$. For each $n \in \mathbb{N}$ define the set $A_n(\epsilon)$ to be the set of elements in $E$ such that $|f_k(x) - f(x)| < \epsilon$ where $k \in \{ n, n+1, ... \}$. That is:
(2)
\begin{align} \quad A_n(\epsilon) = \{ x \in E : |f_k(x) - f(x)| < \epsilon, \: k \in \{ n, n+1, ... \} \} \end{align}
• Consider the condition that $(f_n(x))_{n=1}^{\infty}$ converges uniformly to $f(x)$ on any set $A \subseteq E$ means that for all $\epsilon > 0$ there exists an $N \in \mathbb{N}$ such that if $n \geq N$ then $|f_n(x) - f(x) | < \epsilon$ for all $x \in A$. By the definition of the sets $A_n(\epsilon)$ above, we have that $(f_n(x))_{n=1}^{\infty}$ converges uniformly to $f(x)$ on $A$ if and only if for all $\epsilon > 0$ there exists an $N \in \mathbb{N}$ such that if $x \in A$ then:
(3)
\begin{align} \quad x \in A_N(\epsilon) \end{align}
• Equivalently, $(f_n(x))_{n=1}^{\infty}$ converges to $f(x)$ on $A$ if and only if for all $\epsilon > 0$ there exists an $N \in \mathbb{N}$ such that:
(4)
\begin{align} \quad A \subseteq A_N(\epsilon) \end{align}
• Furthermore, we note that for a fixed $\epsilon > 0$, the collection of sets $A_1(\epsilon)$, $A_2(\epsilon)$, …, $A_N(\epsilon)$, … is a ascending sequence of sets:
(5)
\begin{align} \quad A_1(\epsilon) \subseteq A_2(\epsilon) \subseteq ... \subseteq A_N(\epsilon) \subseteq A_{N+1} (\epsilon) \subseteq ... \end{align}
• Let $\epsilon > 0$. Since $(f_n(x))_{n=1}^{\infty}$ converges pointwise to $f(x)$ on $E$ we have that for this given $\epsilon$, for each $x \in E$ there exists an $N(\epsilon, x) \in \mathbb{N}$ such that if $n \geq N_0$ then:
(6)
\begin{align} \quad | f_n(x) - f(x) | < \epsilon \end{align}
• So for each $x \in E$ there exists an $N(\epsilon, x) \in \mathbb{N}$ such that $x \in A_{N(\epsilon, x)}(\epsilon)$ and hence:
(7)
\begin{align} \quad E = \bigcup_{n=1}^{\infty} A_n(\epsilon) \end{align}
• For each $N \in \mathbb{N}$ let $\displaystyle{\epsilon_k = \frac{1}{k} > 0}$. For each $n \in \mathbb{N}$ consider the sets $\displaystyle{A_n (\epsilon_k) = A_n \left ( \frac{1}{k} \right )}$. Then:
(8)
\begin{align} \quad E = \bigcup_{n=1}^{\infty} A_n \left ( \frac{1}{k} \right ) \end{align}
• Additionally since $\left ( A_n \left ( \frac{1}{k} \right ) \right )_{n=1}^{\infty}$ is a sequence of ascending sets that converges to $E$, for each $\displaystyle{\epsilon_k = \frac{\epsilon}{2^{k+1}} > 0}$ there exists an $N_k \in \mathbb{N}$ such that:
(9)
\begin{align} \quad m \left ( E \setminus A_{N_k} \left ( \frac{1}{k} \right ) \right ) < \epsilon_k = \frac{\epsilon}{2^{k+1}} \quad (*) \end{align}
• Let:
(10)
\begin{align} \quad A = \bigcap_{k=1}^{\infty} A_{N_k} \left ( \frac{1}{k} \right ) \end{align}
• Consider the Lebesgue measure of $m(E \setminus A)$:
(11)
\begin{align} \quad m (E \setminus A) &= m \left ( E \setminus \bigcap_{k=1}^{\infty} A_{N_k} \left ( \frac{1}{k} \right ) \right ) \\ &= m \left ( \bigcup_{k=1}^{\infty} \left ( E \setminus A_{N_k} \left ( \frac{1}{k} \right ) \right ) \right ) \\ & \leq \sum_{k=1}^{\infty} m \left ( E \setminus A_{N_k} \left ( \frac{1}{k} \right ) \right ) \\ & \overset{(*)} \leq \sum_{k=1}^{\infty} \frac{\epsilon}{2^{k+1}} \\ & \leq \frac{\epsilon}{2} \end{align}
• So for every $\epsilon > 0$, let $k \in \mathbb{N}$ be such that $\displaystyle{\frac{1}{k} < \epsilon}$. Then:
(12)
\begin{align} \quad A = \bigcap_{k=1}^{\infty} A_{N_k} \left ( \frac{1}{k} \right ) \subseteq A_{N_k} \left ( \frac{1}{k} \right ) \subseteq A_{N_k} (\epsilon) \end{align}
• So $(f_n(x))_{n=1}^{\infty}$ converges uniformly to $f(x)$ on $A$. Since $A \subseteq E$ and $m(E) < \infty$ we have that $m(A) < \infty$. So there exists a closed set $F \subseteq A$ such that $\displaystyle{m(A \setminus F) < \frac{\epsilon}{2}}$ and hence:
(13)
\begin{align} \quad m(E \setminus F) = m(E \setminus A) + m(A \setminus F) < \frac{\epsilon}{2} + \frac{\epsilon}{2} = \epsilon \end{align}
• And since $(f_n(x))_{n=1}^{\infty}$ converges uniformly to $f(x)$ on $A$ we also have that $(f_n(x))_{n=1}^{\infty}$ converges uniformly to $f(x)$ on $F$. $\blacksquare$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 13, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9999996423721313, "perplexity": 171.62507031733423}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-50/segments/1480698540409.8/warc/CC-MAIN-20161202170900-00154-ip-10-31-129-80.ec2.internal.warc.gz"} |
https://www.fyears.org/ | quick note after installing windows 10 pro
This is the quick note before and after installing Windows 10 pro.
open HEIF and HEVC files in Windows
A few days ago, I wanted to transfer photos from my iPhone to my computer. But it was very annoying that after copying for a while, the process stopped with some errors occured.
enable "Open PowerShell window here" in right click context menu
In Windows 10 Anniversary Update and later Creators Update, if we press “shift” key and right click on desktop, drive, folder, folder blackground, we could see the menu “Open PowerShell window here”. It’s convenient for development. But how to reveal the menu?
Electron as GUI of Python Applications (Updated)
tl;dr
This post shows how to use Electron as the GUI component of Python applications. (Updated version of one of my previous posts.) The frontend and backend communicate with each other using zerorpc. The complete code is on GitHub repo.
topological sorting using DFS and BFS
topological sorting can be solved using DFS and BFS in asymptotical time complexity $O(V + E)$.
learn React the easy way
tl;dr
Remember the core idea in React: UI = func(const props, state).
One of the correct ways to start JS projects in 2017
tl;dr
I choose to use create-react-app, then use ES2016 standard to write react to build the UI and use redux to manage the data, and write flexbox to manage layouts in CSS, if I am going to start a completely new general-purposes front end project in early 2017.
This post discusses the $O(n^2)$, $O(n log(n))$ complexity methods to find the length of longest increasing subsequence (LIS), and the way to recover the subsequence. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.33062514662742615, "perplexity": 4380.240601321261}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-24/segments/1590347390755.1/warc/CC-MAIN-20200526081547-20200526111547-00210.warc.gz"} |
http://math.stackexchange.com/questions/203720/need-help-figuring-out-fracddxx2x-3 | Need help figuring out $\frac{d}{dx}(x^2)|{x=3}$
Okay, I punched this into my new calculator:
$$\frac{d}{dx}(x^2)|{x=3}$$
and it all is equal to $6$. What is this called and/or what does it do?
-
Evaluating a derivative of x^2 in respect to x at a fixed point (x = 3). Where did the sin term come from (another question)? – Amzoti Sep 28 '12 at 1:51
I got rid of it. I was just trying to figure out the math coding thing – name not important Sep 28 '12 at 1:52
Ok its called a derivative. Thank you Amzoti. – name not important Sep 28 '12 at 1:53
You shouldn't write a "thank you" as an answer. This site does not function as a forum where you can write posts. It is a question and answer format. Please see the FAQ. – Thomas Sep 28 '12 at 2:01
Yeah and under etiquette it says to be nice. not vote people down for saying "thank you" – name not important Sep 28 '12 at 2:14
Use simple derivative formula to solve this problem.
In this case use the formula:
$\frac{d}{dx}(x^2) = 2x$
Now put $x=3$
Answer will then come to $6$
For formulas, you may refer to: Basic Differentiation Formulas
- | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9412159323692322, "perplexity": 1295.6194497144882}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-32/segments/1438042986615.83/warc/CC-MAIN-20150728002306-00043-ip-10-236-191-2.ec2.internal.warc.gz"} |
https://aman.ai/cs230/ | CS230: Deep Learning
A distilled compilation of my notes for Stanford's CS230: Deep Learning.
Notes
Deep Learning Intro and Applications
intro; examples of deep learning projects
Deep Learning Intuition
neural network basics
attacking networks with adversarial/fooling examples; GANs
Full-cycle of a Deep Learning Project
practical aspects of deep learning; optimization
Deep Reinforcement Learning
Markov decision process; Bellman equation; Deep Q-learning
Course Info
Course description:
• Deep Learning is one of the most highly sought after skills in AI. In this course, you will learn the foundations of Deep Learning, understand how to build neural networks, and learn how to lead successful machine learning projects.
• You will learn about Convolutional networks, RNNs, LSTM, Adam, Dropout, BatchNorm, Xavier/He initialization, and more.
Credits
The in-line diagrams are taken from the CS230 lecture slides, unless specified otherwise.
Citation
If you found our work useful, please cite it as:
@misc{Chadha2020DistilledNotesCS230,
A. Chadha, Distilled Notes for Stanford CS230: Deep Learning, https://www.aman.ai, 2020, Accessed: Sept 1 2020. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5069522261619568, "perplexity": 16129.993417247562}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964362952.24/warc/CC-MAIN-20211204063651-20211204093651-00178.warc.gz"} |
https://www.physicsforums.com/threads/alternate-way-of-differentiating-x-y.918472/ | # Alternate way of differentiating x^y
Tags:
1. Jun 24, 2017
### randomgamernerd
1. The problem statement, all variables and given/known data: find the dy/dx of xy=a constant
2. Relevant equations: basic differentiation formulae
3. The attempt at a solution:
I know we can use logarithmic differentiation for differentiating x y..But can we differentiate it using chain rule and get answer as
yxy-1.dy/dx =0. ???
2. Jun 24, 2017
The answer is no. If $y=u^n$, (for $n$ being a constant), then $\frac{dy}{dx}=nu^{n-1} \frac{du}{dx }$. The operation you are attempting to do doesn't work.
3. Jun 24, 2017
### pasmith
The chain rule would give you $(y^x)' = (e^{(x \ln y)})' = (x \ln y)'y^x$ etc.
4. Jun 24, 2017
### Staff: Mentor
I think you meant $x^y$
5. Jun 24, 2017
### LCKurtz
Since $x^y$ is a power function of $x$ and an exponential function of $y$, which depends implicitly on $x$, you can't use either just the power rule or just the exponential rule for differentiation. But you can do it by the two-variable chain rule, if you have studied that. One form of it states that if $u$ and $v$ are functions of $x$ and you have a function $f(u,v)$ which you would like to differentiate with respect to $x$, can use$$\frac{df}{dx} = f_u\frac{du}{dx} + f_v\frac{dv}{dx}$$where the subscripts are partial derivatives. In your example $x^y = c$ think of $u=x$ and $v = y$ and $f(x,y) = x^y = c$. So you get$$f_x\frac{dx}{dx}+ f_y\frac{dy}{dx} = yx^{y-1}\cdot 1 + x^y \ln x \frac{dy}{dx} = 0$$If you solve that for $\frac{dy}{dx}$ and simplify it you will get the same answer as you get with logarithmic differentiation. Try it. You might find it interesting. Notice that in the process of doing that you use both the power and exponential rules for differentiation. Makes sense, no?
6. Jun 25, 2017
### randomgamernerd
Ok...Cool..
7. Jun 25, 2017
### randomgamernerd
Thanks Everyonee
Draft saved Draft deleted
Similar Discussions: Alternate way of differentiating x^y | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 2, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9700878262519836, "perplexity": 609.8666956728349}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-51/segments/1512948567042.50/warc/CC-MAIN-20171215060102-20171215080102-00499.warc.gz"} |
https://quantumcomputing.stackexchange.com/questions/16621/quantum-circuit-for-eiat-hamiltonian-simulation-in-hhl-algorithm | # Quantum Circuit for $e^{iAt}$ Hamiltonian Simulation in HHL algorithm
In HHL algorithm, there is a step in Quantum Phase Estimation where we have to apply powers of $$e^{iAt}$$ to the register (see pic). I am not able to understand how to find the quantum circuit corresponding to this unitary transformation i.e. if I know $$A$$, then how to find the decomposition of this operator in terms of quantum gates.
As an exapmle, Cao et al. v2 , Cao et al. v3 - in these papers the authors have decomposed the operator in terms of basic gates, but I am not able to understand, how they have done that. So, I am not able to understand how to decompose the operator $$e^{iAt}$$ in terms of basic gates for any Hermitian Matrix $$A$$ .
• Converting a given Hamiltonian $A$ into a sequence of gates $e^{iAt}$ is called Hamiltonian simulation, which is a topic unto itself. This depends very much on the nature of the Hamiltonian - e.g. how local or how sparse it is, how easy it is to determine entries of the matrix, etc. HHL left the Hamiltonian simulation of $A$ as a black box, but there are lots of algorithms now known to efficiently perform Hamiltonian simulation. Wikipedia lists a couple - many of these were optimized after HHL's paper. Mar 22, 2021 at 15:04
• +1 to what @MarkS said. In addition, the circuit implementing $e^{iAt}$ depends on the choice of basic gates. In fact, the circuit ranges from trivial (when $U=e^{iAt}$ is one of the basic gates) to potentially impossible (when the set of basic gates is not universal). Mar 22, 2021 at 17:15
• I recommend you ask another question specific to the paper(s). But briefly at the bottom of FIG. 4 of version 2 of the paper the authors provide the unitary which is equivalent to their $e^{iAt}$ for their example matrix $A$ given in equation $1$ of their paper. They appear to rely on Group Leader Optimization for their Hamiltonian simulation, which I've not heard of but is discussed on this site here. Any further details you'd likely have to be more specific. Mar 22, 2021 at 19:57
• @quankid Note that you can decompose $A$ as follow: $A = 3.75II + 1.25XZ + 0.75YY + 2.25 ZX$. Now you can use trotterization... but maybe there is a clever way to do this for this specific problem. In general, given a Hermitian matrix $A$, you always can decomposed $A$ in term of pauli string, then use trotterization to approximate $e^{iAt}$. If you are using qiskit then this can be done very quickly. Mar 22, 2021 at 20:13
• @KAJ226 May I know how did you find the coefficients of Pauli matrices. Also, can you explain in detail how can this be done using qiskit. I would be thankful if you could write a detailed answer below. Mar 22, 2021 at 20:20
As requested through the comment by the OP.
Given a Hermitian matrix $$H$$, we can always write it as linear combination of Pauli strings. That is,
$$H = \sum_i \alpha_i P_i \hspace{1 cm} P_i \in \{I,X,Y,Z\}^{\otimes n}$$
note this linear combination can have up to $$4^n$$ terms. Thus, for a general Hamiltonian splitting it into linear combination of Pauli terms can be hard and inefficient. However, many interesting Hamiltonian have very efficient decomposition (the linear combination scales polynomial). For instance, the electronic structure Hamiltonian for molecule.
Now, the coefficients $$\alpha_i$$ can be determined through the formula $$\alpha_i = \dfrac{1}{2^n}Tr(P_i H)$$
So here, we are given that $$H = A =\dfrac{1}{4} \begin{pmatrix} 15 & 9 & 5 & -3\\ 9 & 15 & 3 & -5\\ 5 & 3 & 15 & -9 \\ -3 & -5 & -9 & 15 \end{pmatrix}$$.
so for instance, $$\dfrac{1}{2^2}Tr(II \cdot H)=\dfrac{1}{2^2} Tr\bigg(\begin{pmatrix} 1 & 0 & 0 & 0\\ 0 & 1 & 0 & 0\\ 0 & 0 & 1 & 0 \\ 0 & 0 & 0 & 1 \end{pmatrix} \dfrac{1}{4} \begin{pmatrix} 15 & 9 & 5 & -3\\ 9 & 15 & 3 & -5\\ 5 & 3 & 15 & -9 \\ -3 & -5 & -9 & 15 \end{pmatrix} \bigg)= \dfrac{1}{2^2} Tr\bigg(\begin{pmatrix} 3.75 & 2.25 & 1.25 & -0.75\\ 2.25 & 3.75 & 0.75 & -1.25\\ 1.25 & 0.75 & 3.75 & -2.25 \\ -0.75 & -1.25 & -2.25 & 3.75\end{pmatrix} \bigg) = 3.75$$
Similarly, $$\dfrac{1}{4}Tr( XZ \cdot H) = 1.25$$, $$\dfrac{1}{4}Tr( ZX \cdot H) = 2.25$$, and $$\dfrac{1}{4}Tr( YY \cdot H ) = 0.75$$.
The rest of the coefficients are $$0$$. For instance, $$\dfrac{1}{4}Tr( IX) = 0$$, and $$\dfrac{1}{4}Tr( YX) = 0$$, etc.
Once you have the Pauli string decomposition, you can input this into quiskit to create a circuit that approximate (if the pauli terms don't commute with each other) the operation $$e^{iAt}$$ through Trotterization (look at page 207 here to know more about this technique) pretty quickly using their WeightedPauliOperator as follow:
from qiskit.aqua.operators import WeightedPauliOperator
pauli_dict = {'paulis': [{"coeff": {"imag": 0, "real": 3.75 }, "label": "II"},
{"coeff": {"imag": 0, "real": 1.25 }, "label": "XZ"},
{"coeff": {"imag": 0, "real": 0.75 }, "label": "YY"},
{"coeff": {"imag": 0, "real": 2.25 }, "label": "ZX"},
]}
operator = WeightedPauliOperator.from_dict(pauli_dict)
approx_circuit = operator.evolve(evo_time= 1, num_time_slices=1).decompose()
Note that you have option to change the evolution time and number of time slices in the evolve method. But note that all the Pauli terms here commute with each other so this is not an approximation but exact representation of the circuit. The reason is if $$A$$ and $$B$$ are two commuting matrix, $$[A,B] = AB - BA = 0$$, then $$e^{A+B} = e^Ae^B$$. Here $$II$$ commute with everything, and $$[XZ,ZX] = 0$$, $$[ZX,YY] = 0$$, and $$[XZ,YY] = 0$$ .
Which would output something like:
and if you want to transpiled to a specific gate set that you want to use, you can use the transpile function:
from qiskit.compiler import transpile
transpiled_circuit = transpile(approx_circuit, basis_gates=['cx', 'u3'], optimization_level = 3)
Then now, if you want to create the controlled version of $$Controlled-e^{iAt}$$ then you can create a controlled gate to all the gates you have in the circuit. But then you would still need to decompose those controlled operations to native gates that matches the device's native gate set. You can also do this automatically with qiskit too, actually. That is, you can just create a controlled version of the entire circuit above. Let's suppose the circuit to simulate $$e^{iAt}$$ is described as the transpiled_circuit we have above, then what I can do is:
from qiskit import QuantumRegister, QuantumCircuit
xs_gate = transpiled_circuit.to_gate()
cxs_gate = xs_gate.control()
qreg_q = QuantumRegister(3, 'q')
circuit = QuantumCircuit(qreg_q)
circuit.append(cxs_gate, [0,1,2])
This will create the circuit:
where the circuit231 represents the entire transpiled_circuit we had above. You can then again* decompose this circuit to see what it would look like in term of more elementary gates:
decomposed_circuit = circuit.decompose().decompose()
which can give you something ridiculously long:
What I described is for a general case. For specific problem, you can use different tricks to make this neater. For instance, see this amazing answer by Adam.
• KAJ226, I think there is a typo: it should be $\frac{1}{4}Tr(XZ \cdot H)$ instead of $\frac{1}{4}Tr(XZ)$ and similarly, for the other terms, am I right? Mar 23, 2021 at 15:07
• @DavitKhachatryan Yes! Thank you! :) Mar 23, 2021 at 15:24 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 28, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9029601216316223, "perplexity": 555.6249538615943}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-14/segments/1679296945279.63/warc/CC-MAIN-20230324082226-20230324112226-00212.warc.gz"} |
http://mathematica.stackexchange.com/questions/13158/generating-continuous-products-or-sum | # Generating continuous products or sum
This is kind of a continuation of this question.
I want to automate these 2 steps on Mathematica once I give an integer $N$.
• generate a list of variables $\{a_i\}_{i=1}^{i=N}$
• then for some function like $f(x) = e^{x}$ or $f(x) = \sin^2(x)$ compute an expression like $\prod\limits_{i \neq j} f(a_i - a_j)$ or $\sum\limits_{i < j} f(a_i - a_j)$ or $\prod\limits_ {i,j} f(a_i - a_j)$
( - and then hopefully integrate such expressions over all $a_i$...)
I am having to type these expressions by hand for every $N$ and that is very hard once $N$ gets large (one would typically have $\binom{N}{2}$ terms to type by hand!) I would like to know how this can be automated - since I would typically need to to use large $N$.
(...also, help with that previous question would be great!)
-
Implementing for example $\prod_{j>i}^Nf(a_i-a_j)$:
nup = 4;
where nup is $N$.
...or With[{nup = 6}, Times @@ f /@ Subtract @@@ Subsets[Array[a, nup], {2}]] – J. M. Oct 16 '12 at 18:51 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6089919209480286, "perplexity": 909.7034317950422}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-22/segments/1464049274191.57/warc/CC-MAIN-20160524002114-00216-ip-10-185-217-139.ec2.internal.warc.gz"} |
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### I can Euler-sum $\sqrt{-\ln(1)}-\sqrt{-\ln(2)}+\sqrt{-\ln(3)}-\cdots$. But how can I do $\sqrt{-\ln(1)}+\sqrt{-\ln(2)}+\sqrt{-\ln(3))}+\cdots$?
apr 21 at 0:34 Gottfried Helms 15.5k
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### A Ramanujan-like summation: is it correct? Is it extensible?
mar 7 '14 at 8:36 Gottfried Helms 15.5k
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http://cerco.cs.unibo.it/changeset/1676 | # Changeset 1676
Ignore:
Timestamp:
Feb 6, 2012, 6:50:57 PM (6 years ago)
Message:
corrected some faults
still TODO: running example, language corrections
Location:
r1674 of the compiled code which have constant cost. There are two properties one asks of the cost estimate. The first, paramount to There are two properties one asks of the cost estimate. The first one, paramount to the correctness of the method, is \emph{soundness}: the actual execution cost is bounded by the estimate. In the labelling approach, this is guaranteed if every loop in the control flow of the compiled code passes through at least one cost label. The second, optional but desirable, is \emph{preciseness}: the estimate is not in fact an estimate but the actual cost. In the labelling approach, this will label. The second one, optional but desirable, is \emph{preciseness}: the estimate \emph{is} the actual cost. In the labelling approach, this will be true if for every label every possible execution of the compiled code starting from such a label yields the same cost. In simple architectures such as the 8051 from such a label yields the same cost before hitting another one. In simple architectures such as the 8051 micro-controller this can be guaranteed by having labels at the immediate start of any branch of the control flow, and by ensuring no duplicate labels are present. It should be underlined that the above mentioned requirements must hold when executing the code at the end of the compilation chain. If one is careful to inject the labels at good key places in the source code, one can still think of two main obstacles: executing the code obtained at the end of the compilation chain. So even If one is careful injecting the labels at good key places in the source code, the requirements might still fail because of two main obstacles: \begin{itemize} \item compilation introduces important changes in the control flow, inserting loops or branches: an example in addressing this is the insertion of functions in the source code replacing instructions unavailable in the target architecture that require loops (e.g.\ multi-word division and generic shift in the 8051 architecture) so that the annotation process be sound, or the effort put in and that require loops to be carried out (e.g.\ multi-word division and generic shift in the 8051 architecture), or the effort put in providing unbranching translations of higher level instructions~ \cite{D2.2}; comes to some common code transformations done along a compilation chain. In particular most of \emph{loop optimizations} disrupt such conditions directly. For example in what we will call \emph{loop peeling} a first iteration of the In what we will call \emph{loop peeling}, for example, a first iteration of the loop is hoisted ahead of it, possibly to have a different cost than later iterations because of further transformation such as dead code elimination or invariant code motion. The second point strikes a difference in favour to existing tools for the estimate of execution costs to the detriment of CerCo's approach advocated in~ \cite{D2.1}. We will take as example the well known tool \s{aiT}~\cite{absint}, The second point strikes a difference in favour of existing tools for the estimate of execution costs and to the detriment of CerCo's approach advocated in~ \cite{D2.1}. We will take as an example the well known tool \s{aiT}~\cite{absint}, based on abstract interpretation: such a tool allows to estimate the worst-case execution time (WCET) taking into account advanced aspects of the presented in~\cite{D2.1} is common to both points: the inability to state different costs for different occurrences of labels, where the difference might be originated by labels being duplicated along compilation or the costs being sensitive to the state of execution. might be originated by labels being duplicated along the compilation or the costs being sensitive to the current state of execution. The preliminary work we present here addresses this node, introducing cost labels that are dependent we present here addresses this weakness by introducing cost labels that are dependent on which iteration of its containing loops it occurs in. This is achieved by means of \emph{indexed labels}: all cost labels are decorated with formal code. Integrating this transformation to the labelling approach would also allow to integrate the common case of cache analysis explained above: the analysis of cache hits and misses in the case of usually benefits from a form of of cache hits and misses usually benefits from a form of \emph{virtual} loop peeling~\cite{cacheprediction}. to present the development and the problems it is called to solve. The version of the minimal imperative language \imp that we will present has, The version of the minimal imperative language \imp{} that we will present has, with respect to the bare-bone usual version, \s{goto}s and labelled statements. Break and continue statements can be added at no particular expense. Its syntax \end{array} \end{gathered}$$\caption{The syntax and operational semantics of \imp.} \label{fig:minimp} The actual grammar for expressions is not particularly relevant so we do not give a precise one. For the sake of this presentation we also treat boolean and precise one. For the sake of conciseness we also treat boolean and arithmetic expressions together (with the usual convention of an expression being true iff non-zero). being true iff non-zero). We may omit the \s{else} clause of a conditional if it leads to a \s{skip} statement. We will suppose programs are \emph{well-labelled}, i.e.\ every label labels at most one occurrence of statement in the program, and every \s{goto} points to a label actually present in the program. The \s{find} helper functions has the task of not only finding the labelled The \s{find} helper function has the task of not only finding the labelled statement in the program, but also building the correct continuation. The continuation built by \s{find} replaces the current continuation in the case of a jump. unreachable \s{goto} jumping to them.}. Many loop optimizations do not preserve the semantics of multi-entry loops in general, or are otherwise rendered ineffective. Usually compilers implement a multi-entry loop detection which avoids those loops from being targeted by optimizations~\cite{muchnick,morgan}. ineffective. Usually compilers implement a single-entry loop detection which avoids the multi-entry ones from being targeted by optimizations~\cite{muchnick,morgan}. The loop transformations we present are local, i.e.\ they target a single loop and transform it. Which loops are targeted may be decided by an \emph{ad hoc} heuristic, however this is not important here. \end{array}$$ where we identify cost labels $\alpha$ with singleton traces and we use $\varepsilon$ for the empty trace. We then write $\to[\lambda]\!\!^*$ for the transitive for the empty trace. Cost labels are emitted by cost-labelled statements only% \footnote{In the general case the evaluation of expressions can emit cost labels too (see \autoref{sec:conc}).}. We then write $\to[\lambda]\!\!^*$ for the transitive closure of the small step semantics which produces by concatenation the trace $\lambda$. containing $\ell$, or the empty path if none exists; and $\s{gotosof}_P$ from a label $\ell$ to the occurrences of \s{goto}s pointing to it. Then the set $\s{multyentry}_P$ of multy-entry loops of $P$ can be computed by adding to it all occurrences $p$ such that there exists a label $\ell$ and an occurrence $q$ with $\s{loopof}_P(\ell)=p$, $q\in \s{gotosof}_P(\ell)$ and $p\not\le q$ (where $\le$ is the prefix relation)\footnote{Possible simplification to this $\s{multientry}_P$ of multi-entry loops of $P$ can be computed by $$\s{multientry}_P\ass\{\, p \mid \exists \ell,q.p =\s{loopof}_P(\ell),q\in\s{gotosof}_P(\ell), q \not\le p\,\}$$ where $\le$ is the prefix relation\footnote{Possible simplification to this procedure include keeping track just of while loops containing labels and \s{goto}s (rather than paths in the syntactic tree of the program), and making \begin{array}{lh{-100pt}l} (i_k:\sop{while}b\sbin{do}\alpha\la Id_{k+1}\ra : \Ell^\iota_P(T,k+1));\beta\la Id_k \ra : \s{skip} \\& \text{if $S=\sop{while}b\sbin{do}T$ and $S\notin \s{multyentry}_P$,}\\[3pt] \\& \text{if $S=\sop{while}b\sbin{do}T$ and $S\notin \s{multientry}_P$,}\\[3pt] (\sop{while}b\sbin{do}\alpha\la Id_k \ra : \Ell^\iota_P(T,k));\beta\la Id_k \ra : \s{skip} \\& \text{otherwise, if $S=\sop{while}b\sbin{do}T$,}\\[3pt] $C$ represents a snapshot of loop indexes in the compiled code, while $I\circ C$ is the corresponding snapshot in the source code. Semantics preservation will make sure that when with snapshot $C$ we emit $\alpha\ra I\la$ (that is, will make sure that when with snapshot $C$ we emit $\alpha\la I\ra$ (that is, we have $\alpha\la I\circ C\ra$ in the trace), this means that $\alpha$ must be emitted in the source code with indexing $I\circ C$, so the cost | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7099692225456238, "perplexity": 1085.9664313067883}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-47/segments/1510934805362.48/warc/CC-MAIN-20171119042717-20171119062717-00089.warc.gz"} |
https://www.physicsforums.com/threads/isomorphism-between-groups-direct-product-lcm-and-gcd.287480/ | # Homework Help: Isomorphism between groups, direct product, lcm, and gcd
1. Jan 25, 2009
### Daveyboy
1. The problem statement, all variables and given/known data
Let a,b, be positive integers, and let d=gcd(a,b) and m=lcm(a,b). Show ZaXZb isomorphic to ZdXZm
2. Relevant equations
m=lcm(a,b) implies a|m, b|m and if a,b|c then m|c.
d=gcd(a,b) implies d|a, d|b and if c|a and c|b then d|c
let n be an integer with prime decomposition n=p1a1...pkak
then Zn=Zp1a1X...XZp1ak
3. The attempt at a solution
It is clear that d|m
I considered the prime decomposition of a and b as sets, denote as A and B respectively, and consider the intersection, call this set P. intersection(A,B) = P
Call the product of the elements in this set P'. I claim P' = gcd(a,b), this should be clear.
Then I considered the lcm as the product of the elements in A-P and B-P call these sets A' and B' respectively.
Now we can write the d = lcm(a,b) =A'*B'*P' and this should be clear.
So... now I want to use the isomorphism as described as in the section above, but I don't know what to do. I think I should use ZaXZb is isomorphic to something like
(*)
Zp1k1X...XZpikiXZq1l1X...XZpnln.
where p are the primes of a and q are the primes of b.
Great and now I want to show that that ZdXZm is isomorphic to the same thing, but I'm starting to think that it is not.
I need to make an argument stronger that one of just cardinality, but I don't know what. I'm feel that I need to justify stuff in (*) but I'm not even sure if it is true!
It took me a long time to think of this and I really need to get it done... help would be greatly appreciated. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.957257091999054, "perplexity": 620.0003972665471}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-34/segments/1534221211664.49/warc/CC-MAIN-20180817025907-20180817045907-00406.warc.gz"} |
https://faculty.math.illinois.edu/~west/openp/alonsaks.html | # Alon-Saks-Seymour Conjecture (1994)
Originator(s): N. Alon, M. Saks, P.D. Seymour
Conjecture/Question: Every union of $m$ pairwise edge-disjoint complete bipartite graphs is $(m+1)$-colorable.
Background/motivation: This statement is a bipartite analogue of the Erdos-Faber-Lov\'asz Conjecture. A special case of it would be the Graham-Pollak Theorem stating that the minimum number of complete bipartite subgraphs needed to decompose $K_n$ is $n-1$. Algebraic proofs of this theorem are known, but no purely combinatorial proofs are known.
Comments/Partial results: The conjecture has been shown to be FALSE. Huang-Sudakov [HS] constructed a family of counterexamples having a superlinear gap between the chromatic number and the biclique partition number. They posed a new conjecture that the union of $m$ edge-disjoint bicliques is $2^{(\log_2 m)^2}$-colorable and that this is sharp. The new conjecture is related to a conjecture in theoretical computer science about the complexity of a certain problem.
References:
[GP] R.L. Graham and H.O. Pollak, On embedding graphs in squashed cubes. Graph theory and applications (Proc. Quadrennial Conf. on Graph Theory, Western Michigan Univ., Kalamazoo, Mich., 1972), Lecture Notes in Math. 303 (Springer, 1972), 99-110.
[HS] H. Huang and B. Sudakov, A counterexample to the Alon-Saks-Seymour conjecture and related problems, http://www.math.ucla.edu/~bsudakov/ass-conjecture.pdf , Combinatorica, to appear.
#### Index Page; Glossary
Posted 04/06/05; Last update 09/13/11 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.658380925655365, "perplexity": 1312.1013842382815}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-18/segments/1555578532882.36/warc/CC-MAIN-20190421195929-20190421221929-00494.warc.gz"} |
https://worldwidescience.org/topicpages/c/cardiac+lesions+formed.html | #### Sample records for cardiac lesions formed
1. Post-operative cardiac lesions after cardiac surgery in childhood
International Nuclear Information System (INIS)
A new population of patients in cardiology has been growing steadily so that the number of grown-ups with congenital heart disease (GUCH) is almost equal to those under paediatric care. The dramatic improvement in survival should lead to a larger number of GUCH patients than children with CHD in the new millennium. Although echocardiography remains the imaging modality of choice, cross-sectional imaging techniques have a decision-aiding function for the postoperative evaluation of surgical reconstructions as well as in the preparation of complex interventional procedures. Cardiovascular CT and MRI are often complementary in providing comprehensive complex anatomical evaluation, haemodynamic assessment of residual postoperative lesions and complications of surgery. A thorough understanding of postsurgical corrections is a prerequisite for choosing the optimal imaging techniques and achieving an accurate evaluation. (orig.)
2. Post-operative cardiac lesions after cardiac surgery in childhood
Energy Technology Data Exchange (ETDEWEB)
Ou, Phalla [University Paris Descartes, UFR Necker-Enfants Malades, APHP, Department of Pediatric Radiology, Paris (France); University Paris Descartes, UFR Necker-Enfants Malades, APHP, Department of Cardiology, Centre for Congenital Cardiac Malformations-M3C, Paris (France); Hopital Necker-Enfants Malades, Department of Pediatric Radiology, Paris Cedex 15 (France); Iserin, Laurence; Raisky, Oliver; Vouhe, Pascal; Sidi, Daniel; Bonnet, Damien [University Paris Descartes, UFR Necker-Enfants Malades, APHP, Department of Cardiology, Centre for Congenital Cardiac Malformations-M3C, Paris (France); Brunelle, Francis [University Paris Descartes, UFR Necker-Enfants Malades, APHP, Department of Pediatric Radiology, Paris (France)
2010-06-15
A new population of patients in cardiology has been growing steadily so that the number of grown-ups with congenital heart disease (GUCH) is almost equal to those under paediatric care. The dramatic improvement in survival should lead to a larger number of GUCH patients than children with CHD in the new millennium. Although echocardiography remains the imaging modality of choice, cross-sectional imaging techniques have a decision-aiding function for the postoperative evaluation of surgical reconstructions as well as in the preparation of complex interventional procedures. Cardiovascular CT and MRI are often complementary in providing comprehensive complex anatomical evaluation, haemodynamic assessment of residual postoperative lesions and complications of surgery. A thorough understanding of postsurgical corrections is a prerequisite for choosing the optimal imaging techniques and achieving an accurate evaluation. (orig.)
3. Cardiac motion compensation and resolution modeling in simultaneous PET-MR: a cardiac lesion detection study
Science.gov (United States)
Petibon, Y.; Ouyang, J.; Zhu, X.; Huang, C.; Reese, T. G.; Chun, S. Y.; Li, Q.; El Fakhri, G.
2013-04-01
Cardiac motion and partial volume effects (PVE) are two of the main causes of image degradation in cardiac PET. Motion generates artifacts and blurring while PVE lead to erroneous myocardial activity measurements. Newly available simultaneous PET-MR scanners offer new possibilities in cardiac imaging as MRI can assess wall contractility while collecting PET perfusion data. In this perspective, we develop a list-mode iterative reconstruction framework incorporating both tagged-MR derived non-rigid myocardial wall motion and position dependent detector point spread function (PSF) directly into the PET system matrix. In this manner, our algorithm performs both motion ‘deblurring’ and PSF deconvolution while reconstructing images with all available PET counts. The proposed methods are evaluated in a beating non-rigid cardiac phantom whose hot myocardial compartment contains small transmural and non-transmural cold defects. In order to accelerate imaging time, we investigate collecting full and half k-space tagged MR data to obtain tagged volumes that are registered using non-rigid B-spline registration to yield wall motion information. Our experimental results show that tagged-MR based motion correction yielded an improvement in defect/myocardium contrast recovery of 34-206% as compared to motion uncorrected studies. Likewise, lesion detectability improved by respectively 115-136% and 62-235% with MR-based motion compensation as compared to gating and no motion correction and made it possible to distinguish non-transmural from transmural defects, which has clinical significance given the inherent limitations of current single modality imaging in identifying the amount of residual ischemia. The incorporation of PSF modeling within the framework of MR-based motion compensation significantly improved defect/myocardium contrast recovery (5.1-8.5%, p defect detectability (39-56%, p < 0.01). No statistical difference was found in PET contrast and lesion detectability
4. Electrocardiographic abnormalities and cardiac arrhythmias in structural brain lesions.
Science.gov (United States)
Katsanos, Aristeidis H; Korantzopoulos, Panagiotis; Tsivgoulis, Georgios; Kyritsis, Athanassios P; Kosmidou, Maria; Giannopoulos, Sotirios
2013-07-31
Cardiac arrhythmias and electrocardiographic abnormalities are frequently observed after acute cerebrovascular events. The precise mechanism that leads to the development of these arrhythmias is still uncertain, though increasing evidence suggests that it is mainly due to autonomic nervous system dysregulation. In massive brain lesions sympathetic predominance and parasympathetic withdrawal during the first 72 h are associated with the occurrence of severe secondary complications in the first week. Right insular cortex lesions are also related with sympathetic overactivation and with a higher incidence of electrocardiographic abnormalities, mostly QT prolongation, in patients with ischemic stroke. Additionally, female sex and hypokalemia are independent risk factors for severe prolongation of the QT interval which subsequently results in malignant arrhythmias and poor outcome. The prognostic value of repolarization changes commonly seen after aneurysmal subarachnoid hemorrhage, such as ST segment, T wave, and U wave abnormalities, still remains controversial. In patients with traumatic brain injury both intracranial hypertension and cerebral hypoperfusion correlate with low heart rate variability and increased mortality. Given that there are no firm guidelines for the prevention or treatment of the arrhythmias that appear after cerebral incidents this review aims to highlight important issues on this topic. Selected patients with the aforementioned risk factors could benefit from electrocardiographic monitoring, reassessment of the medications that prolong QTc interval, and administration of antiadrenergic agents. Further research is required in order to validate these assumptions and to establish specific therapeutic strategies.
5. Cardiac motion compensation and resolution modeling in simultaneous PET-MR: a cardiac lesion detection study
International Nuclear Information System (INIS)
Cardiac motion and partial volume effects (PVE) are two of the main causes of image degradation in cardiac PET. Motion generates artifacts and blurring while PVE lead to erroneous myocardial activity measurements. Newly available simultaneous PET-MR scanners offer new possibilities in cardiac imaging as MRI can assess wall contractility while collecting PET perfusion data. In this perspective, we develop a list-mode iterative reconstruction framework incorporating both tagged-MR derived non-rigid myocardial wall motion and position dependent detector point spread function (PSF) directly into the PET system matrix. In this manner, our algorithm performs both motion ‘deblurring’ and PSF deconvolution while reconstructing images with all available PET counts. The proposed methods are evaluated in a beating non-rigid cardiac phantom whose hot myocardial compartment contains small transmural and non-transmural cold defects. In order to accelerate imaging time, we investigate collecting full and half k-space tagged MR data to obtain tagged volumes that are registered using non-rigid B-spline registration to yield wall motion information. Our experimental results show that tagged-MR based motion correction yielded an improvement in defect/myocardium contrast recovery of 34–206% as compared to motion uncorrected studies. Likewise, lesion detectability improved by respectively 115–136% and 62–235% with MR-based motion compensation as compared to gating and no motion correction and made it possible to distinguish non-transmural from transmural defects, which has clinical significance given the inherent limitations of current single modality imaging in identifying the amount of residual ischemia. The incorporation of PSF modeling within the framework of MR-based motion compensation significantly improved defect/myocardium contrast recovery (5.1–8.5%, p < 0.01) and defect detectability (39–56%, p < 0.01). No statistical difference was found in PET contrast and
6. Radionuclide study for cardiac lesion in Duchenne muscular dystrophy
International Nuclear Information System (INIS)
Tl-201 myocardial scintigraphy and radionuclide ventriculography with Tc-99m were performed in 10 patients with Duchenne muscular dystropohy (DMD) and 2 siblings with Becker muscular dystrophy (BMD). Perfusion defect especially in the left ventricular posterolateral wall (LVPLW) and cardiac apex was seen on Tl-201 imaging in 6 of the DMD patients and one of the BMD patients. For these patients, Tc-99m imaging also showed left ventricular local wall motion abnormality in 5 patients and a decreased left ventricular ejection fraction in 4 patients. These findings coincided well with fibrosis of the LVPLW found on autopsy. There were individual differences regarding the occurrence of cardiac complications. One of the BMD patients, as well as DMD patients, had also cardiac complications which have long been considered less common. (Namekawa, K.)
7. Spectrum of cardiac lesions associated with Isolated Cleft Mitral Valve and their impact on therapeutic choices
Science.gov (United States)
El hammiri, Ayoub; Drighil, Abdenasser; Benhaourech, Sanaa
2016-01-01
Background Isolated cleft mitral valve (ICMV) may occur alone or in association with other congenital heart lesions. The aim of this study was to describe the profile of cardiac lesions associated with ICMV and their potential impact on therapeutic management. Methods We conducted a descriptive study with data retrieved from the Congenital Heart Disease (CHD) single-center registry of our institution, including patients with ICMV registered between December 2008 and November 2014. Results Among 2177 patients retrieved from the CHD registry, 22 (1%) had ICMV. Median age at diagnosis was 5 years (6 days to 36 years). Nine patients (40.9%) had Down syndrome. Seventeen patients (77.3%) had associated lesions, including 11 (64.7%) with accessory chordae in the left ventricular outflow tract (LVOT) with no obstruction, 15 (88.2%) had ventricular septal defect (VSD), three had secundum atrial septal defect, and four had patent ductus arteriosus. Thirteen patients (59.1%) required surgical repair. The decision to proceed with surgery was mainly based on the severity of the associated lesion in eight patients (61.5%) and on the severity of the mitral regurgitation in four patients (30.8%). In one patient, surgery was decided based on the severity of both the associated lesion and mitral regurgitation. Conclusion Our study shows that ICMV is rare and strongly associated with Down syndrome. The most common associated cardiac abnormalities were VSD and accessory chordae in the LVOT. We conclude that cardiac lesions associated with ICMV are of major interest, since in this study patients with cardiac lesions were diagnosed earlier. The decision to operate on these patients must take into account the severity of both mitral regurgitation and associated cardiac lesions. PMID:27096525
8. Characteristic lesion pattern and echocardiographic findings in extra-cardiac shunt-related stroke.
Science.gov (United States)
Mun, Jun Kyu; Park, Sung Ji; Kim, Suk Jae; Bang, Oh Young; Chung, Chin-Sang; Lee, Kwang Ho; Kim, Gyeong-Moon
2016-10-15
Among embolic strokes of undetermined source, under-recognized etiology such as extra-cardiac shunt could be a potential risk factor. We sought to characterize infarction patterns on diffusion-weighted imaging (DWI) and transesophageal echocardiography (TEE) findings in extra-cardiac shunt-related stroke. We enrolled 96 consecutive patients with cryptogenic stroke who had an extra- or intra-cardiac shunt. Diagnosis of the shunt was performed using TEE with agitated saline contrast and pulmonary vein isolation. Infarction patterns on DWI and total lesion volume were analyzed. Bubble amounts through the shunt were classified via the International Consensus Criteria (ICC). Short-term prognosis, patterns and size of DWI lesions, and involved vascular territories were not significantly different between two groups. Multivariate analysis revealed that extra-cardiac shunt group has a smaller total infarct volume (odds ratio [OR]=0.427, 95% confidence interval [95% CI] 0.228-0.799, p=0.008), and significantly higher bubble grade during resting state and lower grade during the Valsalva maneuver (OR= 0.539, 95% CI 0.438-0.663, psaline contrast. Further study is needed to confirm whether the extra-cardiac shunt is an independent risk factor. PMID:27653885
9. Repair of DNA lesions associated with triplex-forming oligonucleotides.
Science.gov (United States)
Chin, Joanna Y; Glazer, Peter M
2009-04-01
Triplex-forming oligonucleotides (TFOs) are gene targeting tools that can bind in the major groove of duplex DNA in a sequence-specific manner. When bound to DNA, TFOs can inhibit gene expression, can position DNA-reactive agents to specific locations in the genome, or can induce targeted mutagenesis and recombination. There is evidence that third strand binding, alone or with an associated cross-link, is recognized and metabolized by DNA repair factors, particularly the nucleotide excision repair pathway. This review examines the evidence for DNA repair of triplex-associated lesions. PMID:19072762
10. Terbufos-sulfone exacerbates cardiac lesions in diabetic rats: a sub-acute toxicity study.
Science.gov (United States)
Nurulain, Syed M; Shafiullah, Mohamed; Yasin, Javed; Adem, Abdu; Kaabi, Juma Al; Tariq, Saeed; Adeghate, Ernest; Ojha, Shreesh
2016-06-01
Organophosphorus compounds (OPCs) have a wide range of applications, from agriculture to warfare. Exposure to these brings forward a varied kind of health issues globally. Terbufos is one of the leading OPCs used worldwide. The present study investigates the cardiac effect of no observable dose of a metabolite of terbufos, terbufos-sulfone (TS), under non-diabetic and streptozotocin-induced diabetic condition. One hundred nanomoles per rat (1/20 of LD50) was administered intraperitoneally to adult male Wister rats daily for fifteen days. The left ventricle was collected for ultrastructural changes by transmission electron microscopy. The blood samples were collected for biochemical tests including RBC acetylcholinesterase, creatinine kinase (CK), lactate dehydrogenase (LDH), cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), triglycerides, ALT, AST, and GGT. The study revealed about 10 % inhibition of RBC-AChE in two weeks of TS treatment in non-diabetic rats whereas RBC-AChE activity was significantly decreased in diabetic TS treated rats. CK, LDH, and triglycerides were significantly higher in diabetic TS treated rats. Electron microscopy of the heart showed derangement and lesions of the mitochondria of cardiomyocytes in the TS treated groups. The present study concludes that a non-lethal dose of TS causes cardiac lesions which exacerbate under diabetic condition. Biochemical tests confirmed the ultrastructural changes. It is concluded that a non-lethal dose of TS may be a risk factor for a cardiovascular disease, which may be fatal under diabetic condition. PMID:27331300
11. Diffuse infiltrative cardiac tuberculosis
International Nuclear Information System (INIS)
We present the cardiac magnetic resonance images of an unusual form of cardiac tuberculosis. Nodular masses in a sheet-like distribution were seen to infiltrate the outer myocardium and pericardium along most of the cardiac chambers. The lesions showed significant resolution on antitubercular therapy
12. HEART FAILURE WITH LOW CARDIAC OUTPUT AND RISK OF DEVELOPMENT OF LESIONS IN THE CEREBRAL WHITE MATTER
OpenAIRE
2005-01-01
Aim: Diminished cardiac output can lead to the development of white matter lesions. White matter lesions are related to cognitive impairment, stroke risk and vascular death, yet the precise aetiology is uncertain. Methods: In this study we recruited 130 patients attending our medicine and neurology outpatient department, and divided them into those with a history of heart failure (n:24), atrial fibrillation (n:26), and those with atherosclerotic risk factors (n:80). The patients without low o...
13. Trypanosoma cruzi high infectivity in vitro is related to cardiac lesions during long-term infection in Beagledogs
Directory of Open Access Journals (Sweden)
Paulo MM Guedes
2007-03-01
Full Text Available Trypanosoma cruzi is a hemoflagelate parasite associated with heart dysfunctions causing serious problems in Central and South America. Beagle dogs develop the symptoms of Chagas disease in humans, and could be an important experimental model for better understanding the immunopathogenic mechanisms involved in the chagasic infection. In the present study we investigated the relation among biological factors inherent to the parasite (trypomastigote polymorphism and in vitro infectivity and immunoglobulin production, inflammation, and fibrosis in the heart of Beagle dogs infected with either T. cruzi Y or Berenice-78 strains. In vitro infectivity of Vero cells as well as the extension of cardiac lesions in infected Beagle was higher for Y strain when compared to Berenice-78 strain. These data suggested that in vitro infectivity assays may correlate with pathogenicity in vivo. In fact, animals infected with Y strain, which shows prevalence of slender forms and high infectivity in vitro, presented cardiomegaly, inflammation, and fibrosis in heart area. Concerning the immunoglobulin production, no statistically significant difference was observed for IgA, IgM or IgG levels among T. cruzi infected animals. However, IgA together IgM levels have shown to be a good marker for the acute phase of Chagas disease.
14. Cardiac diastolic dysfunction is associated with cerebral white matter lesions in elderly patients with risk factors for atherosclerosis
International Nuclear Information System (INIS)
Cerebral white matter lesions on magnetic resonance imaging (MRI) are considered to be the result of brain ischemic injury and a risk factor for clinical stroke. The purpose of this study was to elucidate the relationship between the cardiac diastolic function and cerebral white matter lesions in elderly patients with risk factors for atherosclerosis. The study subjects were 55 patients (75±7 years) with risk factors for atherosclerosis including hypertension, diabetes mellitus, and dyslipidemia. Patients with symptomatic cerebrovascular events were excluded from the study. Cerebral white matter lesions, which were defined as exhibiting high intensity regions on brain MRI, were evaluated with the degrees of periventricular hyperintensity (PVH) according to the Japanese Brain Dock Guidelines of 2003. Peak early diastolic mitral annular velocity (E' velocity) was measured by tissue Doppler echocardiography, and was used as a parameter of cardiac diastolic function. The mean value of E' velocity was decreased due to the cardiac diastolic dysfunction (5.2±1.4 cm/s). In addition, the E' velocity was inversely correlated with the degree of PVH (ρ=-0.701, p<0.001). Stepwise regression analysis showed that the decrease in the E' velocity (β coefficient=-0.42, p<0.001) and the presence of hypertension (β coefficient=0.31, p=0.001) were independent determinants of the degree of PVH. Thus, cardiac diastolic dysfunction is correlated to the severity of cerebral white matter lesions, suggesting the cardio-cerebral connection in elderly patients with risk factors for atherosclerosis. (author)
15. Repair of DNA lesions associated with triplex-forming oligonucleotides
OpenAIRE
Chin, Joanna Y; Glazer, Peter M.
2009-01-01
Triplex-forming oligonucleotides (TFOs) are gene targeting tools that can bind in the major groove of duplex DNA in a sequence-specific manner. When bound to DNA, TFOs can inhibit gene expression, can position DNA-reactive agents to specific locations in the genome, or can induce targeted mutagenesis and recombination. There is evidence that third strand binding, alone or with an associated cross-link, is recognized and metabolized by DNA repair factors, particularly the nucleotide excision r...
16. Toxic interaction between fumonisin B1 and moniliformin for cardiac lesions in Japanese quail.
Science.gov (United States)
Sharma, Deepa; Asrani, R K; Ledoux, D R; Rottinghaus, G E; Gupta, V K
2012-09-01
mitochondria resulted in widespread separation of muscle fibers in group MX. In addition, the mitochondria were swollen and varied from round to oval to slightly elongated and occasionally forked, and vacuolation was rarely noticed in group MX. In the FM combination group, a significant increase in the number of mitochondria caused muscle fibers to look much thinner and assume a wavy pattern. We conclude that the effect of M on the heart is exaggerated in the presence of FB1. Although the overall interactive effect of FB1 and M was less than additive, the interactive effects between the two toxins for cardiac lesions were greater than additive to synergistic up to the second week, raising serious concerns on early age exposure to a combination of these two mycotoxins.
17. Cardiac shear-wave elastography using a transesophageal transducer: application to the mapping of thermal lesions in ultrasound transesophageal cardiac ablation.
Science.gov (United States)
Kwiecinski, Wojciech; Bessière, Francis; Colas, Elodie Constanciel; N'Djin, W Apoutou; Tanter, Mickaël; Lafon, Cyril; Pernot, Mathieu
2015-10-21
Heart rhythm disorders, such as atrial fibrillation or ventricular tachycardia can be treated by catheter-based thermal ablation. However, clinically available systems based on radio-frequency or cryothermal ablation suffer from limited energy penetration and the lack of lesion's extent monitoring. An ultrasound-guided transesophageal device has recently successfully been used to perform High-Intensity Focused Ultrasound (HIFU) ablation in targeted regions of the heart in vivo. In this study we investigate the feasibility of a dual therapy and imaging approach on the same transesophageal device. We demonstrate in vivo that quantitative cardiac shear-wave elastography (SWE) can be performed with the device and we show on ex vivo samples that transesophageal SWE can map the extent of the HIFU lesions. First, SWE was validated with the transesophageal endoscope in one sheep in vivo. The stiffness of normal atrial and ventricular tissues has been assessed during the cardiac cycle (n = 11) and mapped (n = 7). Second, HIFU ablation has been performed with the therapy-imaging transesophageal device in ex vivo chicken breast samples (n = 3), then atrial (left, n = 2) and ventricular (left n = 1, right n = 1) porcine heart tissues. SWE provided stiffness maps of the tissues before and after ablation. Areas of the lesions were obtained by tissue color change with gross pathology and compared to SWE. During the cardiac cycle stiffness varied from 0.5 ± 0.1 kPa to 6.0 ± 0.3 kPa in the atrium and from 1.3 ± 0.3 kPa to 13.5 ± 9.1 kPa in the ventricles. The thermal lesions were visible on all SWE maps performed after ablation. Shear modulus of the ablated zones increased to 16.3 ± 5.5 kPa (versus 4.4 ± 1.6 kPa before ablation) in the chicken breast, to 30.3 ± 10.3 kPa (versus 12.2 ± 4.3 kPa) in the atria and to 73.8
18. Cardiac shear-wave elastography using a transesophageal transducer: application to the mapping of thermal lesions in ultrasound transesophageal cardiac ablation
Science.gov (United States)
Kwiecinski, Wojciech; Bessière, Francis; Constanciel Colas, Elodie; Apoutou N'Djin, W.; Tanter, Mickaël; Lafon, Cyril; Pernot, Mathieu
2015-10-01
Heart rhythm disorders, such as atrial fibrillation or ventricular tachycardia can be treated by catheter-based thermal ablation. However, clinically available systems based on radio-frequency or cryothermal ablation suffer from limited energy penetration and the lack of lesion’s extent monitoring. An ultrasound-guided transesophageal device has recently successfully been used to perform High-Intensity Focused Ultrasound (HIFU) ablation in targeted regions of the heart in vivo. In this study we investigate the feasibility of a dual therapy and imaging approach on the same transesophageal device. We demonstrate in vivo that quantitative cardiac shear-wave elastography (SWE) can be performed with the device and we show on ex vivo samples that transesophageal SWE can map the extent of the HIFU lesions. First, SWE was validated with the transesophageal endoscope in one sheep in vivo. The stiffness of normal atrial and ventricular tissues has been assessed during the cardiac cycle (n=11 ) and mapped (n= 7 ). Second, HIFU ablation has been performed with the therapy-imaging transesophageal device in ex vivo chicken breast samples (n = 3), then atrial (left, n= 2 ) and ventricular (left n=1 , right n=1 ) porcine heart tissues. SWE provided stiffness maps of the tissues before and after ablation. Areas of the lesions were obtained by tissue color change with gross pathology and compared to SWE. During the cardiac cycle stiffness varied from 0.5 ± 0.1 kPa to 6.0 ± 0.3 kPa in the atrium and from 1.3 ± 0.3 kPa to 13.5 ± 9.1 kPa in the ventricles. The thermal lesions were visible on all SWE maps performed after ablation. Shear modulus of the ablated zones increased to 16.3 ± 5.5 kPa (versus 4.4 ± 1.6 kPa before ablation) in the chicken breast, to 30.3 ± 10.3 kPa (versus 12.2 ± 4.3 kPa) in the atria and to 73.8 ± 13
19. Image-based modeling and characterization of RF ablation lesions in cardiac arrhythmia therapy
Science.gov (United States)
Linte, Cristian A.; Camp, Jon J.; Rettmann, Maryam E.; Holmes, David R.; Robb, Richard A.
2013-03-01
In spite of significant efforts to enhance guidance for catheter navigation, limited research has been conducted to consider the changes that occur in the tissue during ablation as means to provide useful feedback on the progression of therapy delivery. We propose a technique to visualize lesion progression and monitor the effects of the RF energy delivery using a surrogate thermal ablation model. The model incorporates both physical and physiological tissue parameters, and uses heat transfer principles to estimate temperature distribution in the tissue and geometry of the generated lesion in near real time. The ablation model has been calibrated and evaluated using ex vivo beef muscle tissue in a clinically relevant ablation protocol. To validate the model, the predicted temperature distribution was assessed against that measured directly using fiberoptic temperature probes inserted in the tissue. Moreover, the model-predicted lesions were compared to the lesions observed in the post-ablation digital images. Results showed an agreement within 5°C between the model-predicted and experimentally measured tissue temperatures, as well as comparable predicted and observed lesion characteristics and geometry. These results suggest that the proposed technique is capable of providing reasonably accurate and sufficiently fast representations of the created RF ablation lesions, to generate lesion maps in near real time. These maps can be used to guide the placement of successive lesions to ensure continuous and enduring suppression of the arrhythmic pathway.
20. First experiences with contrast-enhanced first-pass MR perfusion imaging in patients with primary, benign cardiac masses and tumour-like lesions
Energy Technology Data Exchange (ETDEWEB)
2008-08-15
The aim of this study was to evaluate the diagnostic value of contrast-enhanced first-pass perfusion MRI in patients with suspected cardiac masses and tumour-like lesions. Twenty patients underwent contrast-enhanced first-pass saturation-recovery steady-state-free-precession perfusion MRI in addition to clinical MRI. Eleven diagnostic parameters were analysed blinded in consensus by three observers: localisation (paracardiac/mural/intracavitary), malignancy (benign/malignant) and first-pass enhancement pattern (homogeneous/heterogeneous as well as non-perfused/hypoperfused/iso-perfused/ hyperperfused). The results were compared to combined references comprising histology, cytology, medical and surgical reports, echocardiography, chest X-ray, coronary angiography and regular MRI. Also, we analysed if additional first-pass perfusion confirmed, changed or reduced the number of differential diagnoses compared to clinical MRI. All cardiac masses or tumour-like lesions were correctly localised and scored as benign lesions. For homogeneous perfused lesions the sensitivity, specificity, positive and negative predictive value was 94/100/100/67%, 100/94/67/100% for heterogeneous perfused lesions, 92/100/100/88% for non-perfused, 100/94/75/100 for hypoperfused, 100/100/100/100% for hyperperfused and for isoperfused lesions. In 17/2/1 cases perfusion MRI confirmed, reduced or increased the number of potential differentials. First-pass perfusion MRI provides valuable information in patients with benign cardiac masses or tumour-like lesions. Further experience is needed to underline these preliminary observations. (orig.)
1. Lesion-specific coronary artery calcium quantification for predicting cardiac event with multiple instance support vector machines.
Science.gov (United States)
Liu, Qingshan; Qian, Zhen; Marvasty, Idean; Rinehart, Sarah; Voros, Szilard; Metaxas, Dimitris N
2010-01-01
Conventional whole-heart CAC quantification has been demonstrated to be insufficient in predicting coronary events, especially in accurately predicting near-term coronary events in high-risk adults. In this paper, we propose a lesion-specific CAC quantification framework to improve CAC's near-term predictive value in intermediate to high-risk populations with a novel multiple instance support vector machines (MISVM) approach. Our method works on data sets acquired with clinical imaging protocols on conventional CT scanners without modifying the CT hardware or updating the imaging protocol. The calcific lesions are quantified by geometric information, density, and some clinical measurements. A MISVM model is built to predict cardiac events, and moreover, to give a better insight of the characterization of vulnerable or culprit lesions in CAC. Experimental results on 31 patients showed significant improvement of the predictive value with the ROC analysis, the net reclassification improvement evaluation, and the leave-one-out validation against the conventional methods. PMID:20879266
2. Cystitis glandularis forming a tumorous lesion in the urinary bladder: A rare appearance of disease
OpenAIRE
Shigehara, Kazuyoshi; Miyagi, Tohru; Nakashima, Takao; Shimamura, Masayoshi
2008-01-01
We report a rare appearance of cystitis glandularis forming a tumorous lesion with blueberry spots in the urinary bladder. A 49-year-old woman was admitted to our hospital with pollakisuria and recurrent gross hematuria. Urine examination showed no pyuria. Computed tomography (CT) scan showed an extravesical invasive mass and cystoscopy revealed a non-papillary tumor with blueberry spots in the bladder. Transurethral resection (TUR) was performed. Histopathological examination revealed cystit...
3. Real-time optical monitoring of permanent lesion progression in radiofrequency ablated cardiac tissue (Conference Presentation)
Science.gov (United States)
Singh-Moon, Rajinder P.; Hendon, Christine P.
2016-02-01
Despite considerable advances in guidance of radiofrequency ablation (RFA) therapies for atrial fibrillation, success rates have been hampered by an inability to intraoperatively characterize the extent of permanent injury. Insufficient lesions can elusively create transient conduction blockages that eventually reconduct. Prior studies suggest significantly greater met-myoglobin (Mmb) concentrations in the lesion core than those in the healthy myocardium and may serve as a marker for irreversible tissue damage. In this work, we present real-time monitoring of permanent injury through spectroscopic assessment of Mmb concentrations at the catheter tip. Atrial wedges (n=6) were excised from four fresh swine hearts and submerged under pulsatile flow of warm (37oC) phosphate buffered saline. A commercial RFA catheter inserted into a fiber optic sheath allowed for simultaneous measurement of tissue diffuse reflectance (DR) spectra (500-650nm) during application of RF energy. Optical measurements were continuously acquired before, during, and post-ablation, in addition to healthy neighboring tissue. Met-myoglobin, oxy-myoglobin, and deoxy-myoglobin concentrations were extracted from each spectrum using an inverse Monte Carlo method. Tissue injury was validated with Masson's trichrome and hematoxylin and eosin staining. Time courses revealed a rapid increase in tissue Mmb concentrations at the onset of RFA treatment and a gradual plateauing thereafter. Extracted Mmb concentrations were significantly greater post-ablation (p<0.0001) as compared to healthy tissue and correlated well with histological assessment of severe thermal tissue destruction. On going studies are aimed at integrating these findings with prior work on near infrared spectroscopic lesion depth assessment. These results support the use of spectroscopy-facilitated guidance of RFA therapies for real-time permanent injury estimation.
4. Different forms of impairment of the fore-hindlimb coordination after partial spinal lesions in cats.
Science.gov (United States)
Górska, T; Bem, T; Majczyński, H; Zmysłowski, W
1996-01-01
Effects of large low thoracic (T10-T11) partial spinal lesions involving either the ventral quadrants of the spinal cord and, to a different extent the dorsolateral funiculi, or different extent of the lateral funiculi and/or the dorsal columns, on the fore-hindlimb coordination were examined in cats walking overground at moderate speeds. In both groups of operated cats, except those in which the lesion was essentially confined to dorsal columns, three different forms of impairment of fore-hindlimb coordination were observed, depending on the extent of lesion: (1) a change of locomotion towards pacing with preservation of the equality rhythms in the fore- and the hindlimbs; (2) episodes of fore- and hindlimb rhythm dissociation and (3) a permanent dissociation of the fore- and hindlimb rhythms. A comparison of the results obtained in these two groups of operated cats points to the more important role played by the lateral funiculi, than by other parts of the spinal white matter, in controlling the fore-hindlimb coordination in cats.
5. Human embryonic stem cell derived mesenchymal progenitors express cardiac markers but do not form contractile cardiomyocytes.
Directory of Open Access Journals (Sweden)
Christophe M Raynaud
Full Text Available Mesenchymal progenitors or stromal cells have shown promise as a therapeutic strategy for a range of diseases including heart failure. In this context, we explored the growth and differentiation potential of mesenchymal progenitors (MPs derived in vitro from human embryonic stem cells (hESCs. Similar to MPs isolated from bone marrow, hESC derived MPs (hESC-MPs efficiently differentiated into archetypical mesenchymal derivatives such as chondrocytes and adipocytes. Upon treatment with 5-Azacytidine or TGF-β1, hESC-MPs modified their morphology and up-regulated expression of key cardiac transcription factors such as NKX2-5, MEF2C, HAND2 and MYOCD. Nevertheless, NKX2-5+ hESC-MP derivatives did not form contractile cardiomyocytes, raising questions concerning the suitability of these cells as a platform for cardiomyocyte replacement therapy. Gene profiling experiments revealed that, although hESC-MP derived cells expressed a suite of cardiac related genes, they lacked the complete repertoire of genes associated with bona fide cardiomyocytes. Our results suggest that whilst agents such as TGF-β1 and 5-Azacytidine can induce expression of cardiac related genes, but treated cells retain a mesenchymal like phenotype.
6. Newly formed cystic lesions for the development of pneumomediastinum in Pneumocystis jirovecii pneumonia
Directory of Open Access Journals (Sweden)
Yoon Sung
2009-10-01
Full Text Available Abstract Background Pneumocystis jirovecii, formerly named Pneumocystis carinii, is one of the most common opportunistic infections in human immunodeficiency virus (HIV-infected patients. Case presentations We encountered two cases of spontaneous pneumomediastinum with subcutaneous emphysema in HIV-infected patients being treated for Pneumocystis jirovecii pneumonia with trimethoprim/sulfamethoxazole. Conclusion Clinicians should be aware that cystic lesions and bronchiectasis can develop in spite of trimethoprim/sulfamethoxazole treatment for P. jirovecii pneumonia. The newly formed bronchiectasis and cyst formation that were noted in follow up high resolution computed tomography (HRCT but were not visible on HRCT at admission could be risk factors for the development of pneumothorax or pneumomediastinum with subcutaneous emphysema in HIV-patients.
7. Pericardial Effusion with Cardiac Tamponade as a Form of Presentation of Primary Hypothyroidism
Directory of Open Access Journals (Sweden)
Acir Rachid
2002-06-01
Full Text Available The authors describe a case of pericardial effusion accompanied by cardiac tamponade caused by primary hypothyroidism. Diagnosis was made by exclusion, because other causes of cardiac tamponade are more frequent. Emergency treatment of cardiac tamponade is pericardiocentesis (with possible pericardial window, and, after stabilization, performance of hormonal reposition therapy with L-thyroxin.
8. Chemical–Biological Fingerprinting: Probing the Properties of DNA Lesions Formed by Peroxynitrite
OpenAIRE
Delaney, Sarah; James C Delaney; Essigmann, John M.
2007-01-01
DNA-damaging agents usually produce a vast collection of lesions within the genome. Analysis of these lesions from the structural and biological viewpoints is often complicated by the reality that some of the lesions are chemically fragile, leading to an even larger set of secondary and tertiary products. In an effort to deconvolute complex DNA-damage spectra, a strategy is presented whereby an oligonucleotide containing a specific target for chemical reaction is allowed to react with a DNA-d...
9. Comparison of a conventional cardiac-triggered dual spin-echo and a fast STIR sequence in detection of spinal cord lesions in multiple sclerosis
International Nuclear Information System (INIS)
The current optimal imaging protocol in spinal cord MR imaging in patients with multiple sclerosis includes a long TR conventional spin-echo (CSE) sequence, requiring long acquisition times. Using short tau inversion recovery fast spin-echo (fast STIR) sequences both acquisition time can be shortened and sensitivity in the detection of multiple sclerosis (MS) abnormalities can be increased. This study compares both sequences for the potential to detect both focal and diffuse spinal abnormalities. Spinal cords of 5 volunteers and 20 MS patients were studied at 1.0 T. Magnetic resonance imaging included cardiac-gated sagittal dual-echo CSE and a cardiac-gated fast STIR sequence. Images were scored regarding number, size, and location of focal lesions, diffuse abnormalities and presence/hindrance of artifacts by two experienced radiologists. Examinations were scored as being definitely normal, indeterminate, or definitely abnormal. Interobserver agreement regarding focal lesions was higher for CSE (κ=0.67) than for fast STIR (κ=0.57) but did not differ significantly. Of all focal lesions scored in consensus, 47 % were scored on both sequences, 31 % were only detected by fast STIR, and 22 % only by dual-echo CSE (n. s.). Interobserver agreement for diffuse abnormalities was lower with fast STIR (κ=0.48) than dual-echo CSE (κ=0.65; n. s.). After consensus, fast STIR showed in 10 patients diffuse abnormalities and dual-echo CSE in 3. After consensus, in 19 of 20 patients dual-echo CSE scans were considered as definitely abnormal compared with 17 for fast STIR. The fast STIR sequence is a useful adjunct to dual-echo CSE in detecting focal abnormalities and is helpful in detecting diffuse MS abnormalities in the spinal cord. Due to the frequent occurrence of artifacts and the lower observer concordance, fast STIR cannot be used alone. (orig.)
10. Impact of cardiac rehabilitation on angiographic outcomes after drug-eluting stents in patients with de novo long coronary artery lesions.
Science.gov (United States)
Lee, Jong-Young; Yun, Sung-Cheol; Ahn, Jung-Min; Park, Duk-Woo; Kang, Soo-Jin; Lee, Seung-Whan; Kim, Young-Hak; Lee, Cheol Whan; Park, Seong-Wook; Yoo, Yeong Sook; Park, Eun-Kyung; Jin, Young-Soo; Kim, Jeongsoon; Nam, Hyo-Jung; Min, Sun-Yang; Park, Seung-Jung
2014-06-15
Cardiac rehabilitation (CR) can reduce cardiovascular mortality and morbidity in coronary artery disease. Long coronary artery lesions may be associated with adverse outcomes after drug-eluting stent (DES) implantation. The purpose of this study was to evaluate angiographic outcomes after a comprehensive CR program in patients with DESs for long coronary artery lesions. A total of 576 patients treated with DESs for long (≥25 mm) coronary lesions were enrolled in this prospective CR registry. Comprehensive CR programs were successfully performed in 288 patients (50%). The primary end point was in-stent late luminal loss at the 9-month angiographic follow-up. There were few significant differences between the CR and non-CR groups in terms of baseline characteristics, including clinical, angiographic, and procedural variables. The rate of in-stent late luminal loss in the CR group was 35% less than in the usual care group (0.19 ± 0.33 mm in CR vs 0.29 ± 0.45 mm in non-CR, difference 0.08 mm, 95% confidence interval 0.01 to 0.16, p = 0.02) at the 9-month follow-up. After propensity-matched analysis (224 pairs), the results were consistent (0.18 ± 0.31 mm in CR vs 0.28 ± 0.41 mm in non-CR, difference 0.10 mm, 95% confidence interval 0.02 to 0.18, p = 0.02). The CR group showed a significant improvement in the overall risk profile compared with the non-CR group, including current smoking, biochemical profiles, depression, obesity, and exercise capacity. In conclusion, the comprehensive CR program significantly reduced late luminal loss after DES implantation for long coronary lesions. This may be associated with significant improvements in exercise capacity and overall risk profile.
11. Bacterial interference with host epithelial junctional complexes: Probiotic bacteria vs. A/E lesion-forming Escherichia coli
Directory of Open Access Journals (Sweden)
TANIA TOPOUZOVA-HRISTOVA
2012-01-01
Full Text Available During colonization, enteropathogenic (EPEC and enterohaemorrhagic (EHEC Escherichia coli are capable to manipulate host cytoskeleton and colonize gut epithelia by a specific mode of attachment known as the attaching and effacing lesion (A/E lesion. While actin rearrangements during A/E lesion formation have been extensively investigated, the possible alterations of other cytoskeletal elements like those comprising the intercellular junctional complexes (JC of polarized cells during infection have only lately attracted attention. The present mini-review addresses the opposite effects of two groups of bacteria, A/E lesion-forming pathogenic E. coli and probiotic bacterial strains, on JC. JC are important in maintaining gut barrier functions. EPEC and EHEC can disrupt JC which as a consequence leads to reduction in the transepitelial electrical resistance (TER and an increase of the permeability to macromolecules. Probiotic bacteria on the other hand stabilize JC thus increasing TER and reducing permeability to macromolecular markers. Probiotic strains can protect JC integrity of polarized cells from the damage caused by EPEC or EHEC. Together with the promise of these results, of concern is the fact that the outcome of the studies can differ dependent on experimental protocols. Studies with living bacteria and different strain combinations have also put forward strain specific effects. Therefore, an important practical item for future studies is the identification of the molecules synthesized by probiotic bacteria that may be active on JC stability.
12. Comparison of Different Forms of Exercise Training in Patients With Cardiac Disease: Where Does High-Intensity Interval Training Fit?
Science.gov (United States)
Gayda, Mathieu; Ribeiro, Paula A B; Juneau, Martin; Nigam, Anil
2016-04-01
In this review, we discuss the most recent forms of exercise training available to patients with cardiac disease and their comparison or their combination (or both) during short- and long-term (phase II and III) cardiac rehabilitation programs. Exercise training modalities to be discussed include inspiratory muscle training (IMT), resistance training (RT), continuous aerobic exercise training (CAET), and high-intensity interval training (HIIT). Particular emphasis is placed on HIIT compared or combined (or both) with other forms such as CAET or RT. For example, IMT combined with CAET was shown to be superior to CAET alone for improving functional capacity, ventilatory function, and quality of life in patients with chronic heart failure. Similarly, RT combined with CAET was shown to optimize benefits with respect to functional capacity, muscle function, and quality of life. Furthermore, in recent years, HIIT has emerged as an alternative or complementary (or both) exercise modality to CAET, providing equivalent if not superior benefits to conventional continuous aerobic training with respect to aerobic fitness, cardiovascular function, quality of life, efficiency, safety, tolerance, and exercise adherence in both short- and long-term training studies. Finally, short-interval HIIT was shown to be useful in the initiation and improvement phases of cardiac rehabilitation, whereas moderate- or longer-interval (or both) HIIT protocols appear to be more appropriate for the improvement and maintenance phases because of their high physiological stimulus. We now propose progressive models of exercise training (phases II-III) for patients with cardiac disease, including a more appropriate application of HIIT based on the scientific literature in the context of a multimodal cardiac rehabilitation program.
13. Expansion of cardiac ischemia/reperfusion injury after instillation of three forms of multi-walled carbon nanotubes
Directory of Open Access Journals (Sweden)
Urankar Rakhee N
2012-10-01
Full Text Available Abstract Background The exceptional physical-chemical properties of carbon nanotubes have lead to their use in diverse commercial and biomedical applications. However, their utilization has raised concerns about human exposure that may predispose individuals to adverse health risks. The present study investigated the susceptibility to cardiac ischemic injury following a single exposure to various forms of multi-walled carbon nanotubes (MWCNTs. It was hypothesized that oropharyngeal aspiration of MWCNTs exacerbates myocardial ischemia and reperfusion injury (I/R injury. Methods Oropharyngeal aspiration was performed on male C57BL/6J mice with a single amount of MWCNT (0.01 - 100 μg suspended in 100 μL of a surfactant saline (SS solution. Three forms of MWCNTs were used in this study: unmodified, commercial grade (C-grade, and functionalized forms that were modified either by acid treatment (carboxylated, COOH or nitrogenation (N-doped and a SS vehicle. The pulmonary inflammation, serum cytokine profile and cardiac ischemic/reperfusion (I/R injury were assessed at 1, 7 and 28 days post-aspiration. Results Pulmonary response to MWCNT oropharyngeal aspiration assessed by bronchoalveolar lavage fluid (BALF revealed modest increases in protein and inflammatory cell recruitment. Lung histology showed modest tissue inflammation as compared to the SS group. Serum levels of eotaxin were significantly elevated in the carboxylated MWCNT aspirated mice 1 day post exposure. Oropharyngeal aspiration of all three forms of MWCNTs resulted in a time and/or dose-dependent exacerbation of myocardial infarction. The severity of myocardial injury varied with the form of MWCNTs used. The N-doped MWCNT produced the greatest expansion of the infarct at any time point and required a log concentration lower to establish a no effect level. The expansion of the I/R injury remained significantly elevated at 28 days following aspiration of the COOH and N-doped forms, but
14. Radiofrequency Ablation of Accessory Pathways in Chil- dren with Complex Congenital Cardiac Lesions: A Report of Three Cases
Directory of Open Access Journals (Sweden)
2015-10-01
Full Text Available Catheter ablation is an accepted, highly effective modality of treatment for cardiac arrhythmias in children. The success rate depends on the operator’s experience, especially in cases involving complex anatomies. We hereby report our recent experience of successful ablation of accessory pathways in three children with complex congenital heart diseases.The first case was a 7-year-old girl with tricuspid atresia and a previous Glenn shunt, in whom a sub-epicardial overt accessory pathway was successfully ablated via the coronary sinus. The second case, a 9-year-old girl, received accessory pathway ablation via the fenestration of an extracardiac Fontan pathway. The third case was a 14-year-old boy with dextrocardia, common atrium, common ventricle, and a previous extracardiac Fontan operation, in whom ablation of a concealed accessory pathway was carried out retrogradely from the aorta. All the ablations were done in Rajaie Cardiovascular, Medical and Research Center, Tehran, and all the patients were discharged from the hospital without any complication.
15. Papulo-pustulosis form rosacea – results of immunohistochemical research of the condition of the lesions
Directory of Open Access Journals (Sweden)
Sviatenko T.V.
2012-01-01
Full Text Available Studying and the analysis of links pathogenesis papulo-pus tulosis forms of rosacea by means of a wide spectrum of immunohistochemical markers became a research problem. For the decision of tasks in view by the author it is used biopsy a material of 11 diagnosed cases papulo-pus tulosis forms of rosacea at me at the age from 32 till 59 years. Use of immunohis-tochemical methods of research has allowed to reveal new links in pathogenesis of rosacea and to establish a role of some cellular populations of a skin and cages of immune system in progressing of disease and development papulo-pustulosis forms of rosacea. Authors have come to a conclusion that is possible, strengthening of pathological changes at papulo-pustulosis forms of rosacea is caused by presence of pincers which are capable to cause migration in skin CD68+ cages while quantity CD138+ plasmocytes was insignificant and didn't exceed 5-10 % in infiltrates. К i-67+ cages in a considerable quan-tity were as a part of sebaceous glands that specified in progressing hyperplastic changes in these appendages of a skin. Be-sides, the quantity of cages, pos itive on this marker, correlated wi th expressiveness of defeat of sebaceous glands in a greate r degree, than with a disease stage.
16. Rate of cardiac arrhythmias and silent brain lesions in experienced marathon runners: rationale, design and baseline data of the Berlin Beat of Running study
Directory of Open Access Journals (Sweden)
Haeusler Karl
2012-08-01
Full Text Available Abstract Background Regular exercise is beneficial for cardiovascular health but a recent meta-analysis indicated a relationship between extensive endurance sport and a higher risk of atrial fibrillation, an independent risk factor for stroke. However, data on the frequency of cardiac arrhythmias or (clinically silent brain lesions during and after marathon running are missing. Methods/ Design In the prospective observational “Berlin Beat of Running” study experienced endurance athletes underwent clinical examination (CE, 3 Tesla brain magnetic resonance imaging (MRI, carotid ultrasound imaging (CUI and serial blood sampling (BS within 2-3 days prior (CE, MRI, CUI, BS, directly after (CE, BS and within 2 days after (CE, MRI, BS the 38th BMW BERLIN-MARATHON 2011. All participants wore a portable electrocardiogram (ECG-recorder throughout the 4 to 5 days baseline study period. Participants with pathological MRI findings after the marathon, troponin elevations or detected cardiac arrhythmias will be asked to undergo cardiac MRI to rule out structural abnormalities. A follow-up is scheduled after one year. Results Here we report the baseline data of the enrolled 110 athletes aged 36-61 years. Their mean age was 48.8 ± 6.0 years, 24.5% were female, 8.2% had hypertension and 2.7% had hyperlipidaemia. Participants have attended a mean of 7.5 ± 6.6 marathon races within the last 5 years and a mean of 16 ± 36 marathon races in total. Their weekly running distance prior to the 38th BMW BERLIN-MARATHON was 65 ± 17 km. Finally, 108 (98.2% Berlin Beat-Study participants successfully completed the 38th BMW BERLIN-MARATHON 2011. Discussion Findings from the “Berlin Beats of Running” study will help to balance the benefits and risks of extensive endurance sport. ECG-recording during the marathon might contribute to identify athletes at risk for cardiovascular events. MRI results will give new insights into the link
17. Eritema-papulosis form rosacea – results of immunohistochemical research of the condition of the lesions
Directory of Open Access Journals (Sweden)
Haritonova E.G.
2011-01-01
Full Text Available Studying and the analysis of links pathogenesis of eritema-papulosis forms of rosacea by means of a wide spec-trum of immunohistochemical markers became a research problem. Fo r the decision of tasks in view by the author it is used a material of 12 diagnosed cases eritema-papulosis forms of rosacea at men at the age from 32 till 64 years. Use of immunohis-tochemical methods of research has allowed to reveal new links in pathogenesis rosacea and to establish a role of some cellu-lar populations of a skin and cages of imm une system in disease progressing. Besides, at use of the offered scheme of treat-ment dynamics of immunohistochemical indicators was observed considerably more expressed at erit ema-papulosis forms. Treatment influence on an immune link was has been confirmed essential, concerning control, reduction of quantity CD4 + cages, and also changes in quantity CD1 а +, CD138 + that CD68 + cages. Essential re sult the offered scheme gives in a di-rection of suppression of fibrous changes in derma and myofib roblastic transformations dendroc ytes. Considerably the meta-bolism extracellular of matrix improves. Influence of treatment on a vascular component proves to be true reduction of densi-ty of vessels in parallel with decrease in expression VEGF.
18. Cardiac Malpositions
Energy Technology Data Exchange (ETDEWEB)
Yoo, Shi Joon; Im, Chung Gie; Yeon, Kyung Mo; Hasn, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)
1979-06-15
Cardiac Malposition refers to any position of the heart other than a left-sided heart in a situs solitus individual. Associated cardiac malformations are so complex that even angiocardiographic and autopsy studies may not afford an accurate information. Although the terms and classifications used to describe the internal cardiac anatomy and their arterial connections in cardiac malpositions differ and tend to be confusing, common agreement exists on the need for a segmental approach to diagnosis. Authors present 18 cases of cardiac malpositions in which cardiac catheterization and angiocardiography were done at the Department of Radiology, Seoul National University Hospital between 1971 and 1979. Authors analyzed the clinical, radiographic, operative and autopsy findings with the emphasis on the angiocardiographic findings. The results are as follows: 1. Among 18 cases with cardiac malpositions, 6 cases had dextrocardia with situs inversus, 9 cases had dextrocardia with situs solitus and 3 cases had levocardia with situs inversus. 2. There was no genuine exception to visceroatrial concordance rule. 3. Associated cardiac malpositions were variable and complex with a tendency of high association of transposition and double outlet varieties with dextrocardia in situs solitus and levocardia in situs inversus. Only one in 6 cases of dextrocardia with situs inversus had pure transposition. 4. In two cases associated pulmonary atresia was found at surgery which was not predicted by angiocardiography. 5. Because many of the associated complex lesions can be corrected surgically provided the diagnosis is accurate, the selective biplane angiocardiography with or without cineradiography is essential.
19. Cardiac lesions in patients with lethal central nervous system trauma Daño cardíaco en pacientes con trauma mortal del sistema nervioso central
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María E. Cardona
1991-03-01
Full Text Available
Fifteen men with lethal central nervous system trauma were studied to look for the presence of cardiac lesions. They were between 16 and 60 years of age with an average of 32. There were five gunshot wounds and nine central nervous system contusions; four of these occurred in traffic accidents. The remaining patient was wounded with a machete. AII patients were adequately treated since the beginning of their hospital stay and 14 were surgically managed. Average survival after trauma was 6.6 days. In every case there were ECG alterations, the most frequent being sinusal tachycardia. Creatine phosphokinase levels were high in all and the MB fraction was above normal levels in three patients in whom heart damage was confirmed at autopsy. In 40% of cases heart lesions were found and the most common was subendocardial hemorrhage. In an era of increasing need of organs for transplantation potential donors have to be thoroughly studied to determine if heart lesions have occurred and to decide if they are suitable as transplant organs.
Analizamos los casos de 15 hombres con trauma mortal del sistema nervioso central. Sus edades fluctuaron entre 16 y 60 años con un promedio de 32. Las lesiones más frecuentes fueron por proyectil de arma de fuego (5 casos y por contusión (9 casos, cuatro de ellos en accidente de tránsito. El paciente restante fue lesionado con arma corto contundente. En todos los pacientes el manejo fue adecuado desde el principio de la hospitalización ya 14 se les hizo tratamiento quirúrgico. El promedio de sobrevida después del trauma fue 6.6 días. Sin excepción el estudio electrocardiográfico mostró alteraciones; la taquicardia sinusal fue la más frecuente. La CPK estuvo elevada en todos los pacientes; en 3 de ellos, con da
20. Cardiac involvement in patients with systemic lupus erythematosus and correlation of valvular lesions with anti-Ro/SS-A and anti-La/SS-B antibody levels.
Science.gov (United States)
Shahin, Amira A; Shahin, Hesham A; Hamid, Magdy A; Amin, Mona A
2004-01-01
The aim of this study was to evaluate the incidence of morphologic and functional cardiac abnormalities in patients with systemic lupus erythematosus (SLE) and to correlate the findings with levels of anti-Ro/SS-A, anti-La/SS-B, and anti-cardiolipin antibody (aCL). Sixty-two patients with SLE were enrolled in this study. All patients underwent complete history taking, clinical assessment, and standard two-dimensional and Doppler echocardiography. Anti-Ro/SS-A, anti-La/SS-B, and aCL levels were measured using a standardized ELISA test. The patients were subdivided into two subgroups based on the presence or absence of valvular involvement. The two subgroups were then compared. Valvular involvement was present in 19 patients (30.6%), pericardial effusion in 12 patients (19.4%), impaired left ventricular relaxation abnormalities in 2 patients (3.2%), and pulmonary hypertension in 3 patients (4.8%). More patients in the valvular involvement group had positive anti-Ro/SS-A antibodies than in the valvular noninvolvement group (7/19 vs. 4/43). The difference was significant, with P anti-Ro/SS-A levels were significantly higher in the valvular involvement group (33.7 +/- 36.0 vs. 13.7 +/- 25.1; P anti-Ro/SS-A and anti-La/SS-B antibodies and the pathogenesis of the valvular lesions in SLE patients.
1. Genistein promotes endothelial colony-forming cell (ECFC bioactivities and cardiac regeneration in myocardial infarction.
Directory of Open Access Journals (Sweden)
Sang Hun Lee
Full Text Available Although stem cell-mediated treatment of ischemic diseases offers significant therapeutic promise, the limitation in the therapeutic efficacy of transplanted stem cells in vivo because of poor engraftment remains a challenge. Several strategies aimed at improving survival and engraftment of stem cells in the ischemic myocardium have been developed, such as cell transplantation in combination with growth factor delivery, genetic modification of stem cells, and/or cell therapy using scaffolds. To improve therapeutic efficacy, we investigated the effects of genistein on the engraftment of transplanted ECFCs in an acute myocardial ischemia model.We found that genistein treatment enhanced ECFCs' migration and proliferation, which was accompanied by increases in the expression of ILK, α-parvin, F-actin, and phospholylation of ERK 1/2 signaling. Transplantation of genistein-stimulates ECFCs (GS-ECFCs into myocardial ischemic sites in vivo induced cellular proliferation and secretion of angiogenic cytokines at the ischemic sites and thereby enhanced neovascularization and decreased myocardial fibrosis as well as improved cardiac function, as shown by echocardiography. Taken together, these data suggest that pretreatment of ECFCs with genistein prior to transplantation can improve the regenerative potential in ischemic tissues, providing a novel strategy in adult stem cell therapy for ischemic diseases.
2. Stem cells can form gap junctions with cardiac myocytes and exert pro-arrhythmic effects
Directory of Open Access Journals (Sweden)
Nicoline Willemijn Smit
2014-10-01
Full Text Available Stem cell therapy has been suggested to be a promising option for regeneration of injured myocardium, for example following a myocardial infarction. For clinical use cell-based therapies have to be safe and applicable and are aimed to renovate the architecture of the heart. Yet for functional and coordinated activity synchronized with the host myocardium stem cells have to be capable of forming electrical connections with resident cardiomyocytes. In this paper we discuss whether stem cells are capable of establishing functional electrotonic connections with cardiomyocytes and whether these may generate a risk for arrhythmias. Application of stem cells in the clinical setting with outcomes concerning arrhythmogenic safety and future perspectives will also briefly be touched upon.
3. Interconnecting smartphone, image analysis server, and case report forms in clinical trials for automatic skin lesion tracking in clinical trials
Science.gov (United States)
Haak, Daniel; Doma, Aliaa; Gombert, Alexander; Deserno, Thomas M.
2016-03-01
Today, subject's medical data in controlled clinical trials is captured digitally in electronic case report forms (eCRFs). However, eCRFs only insufficiently support integration of subject's image data, although medical imaging is looming large in studies today. For bed-side image integration, we present a mobile application (App) that utilizes the smartphone-integrated camera. To ensure high image quality with this inexpensive consumer hardware, color reference cards are placed in the camera's field of view next to the lesion. The cards are used for automatic calibration of geometry, color, and contrast. In addition, a personalized code is read from the cards that allows subject identification. For data integration, the App is connected to an communication and image analysis server that also holds the code-study-subject relation. In a second system interconnection, web services are used to connect the smartphone with OpenClinica, an open-source, Food and Drug Administration (FDA)-approved electronic data capture (EDC) system in clinical trials. Once the photographs have been securely stored on the server, they are released automatically from the mobile device. The workflow of the system is demonstrated by an ongoing clinical trial, in which photographic documentation is frequently performed to measure the effect of wound incision management systems. All 205 images, which have been collected in the study so far, have been correctly identified and successfully integrated into the corresponding subject's eCRF. Using this system, manual steps for the study personnel are reduced, and, therefore, errors, latency and costs decreased. Our approach also increases data security and privacy.
4. Obesity-related juvenile form of cartilage lesions: a new affliction in the knees of morbidly obese children and adolescents
Energy Technology Data Exchange (ETDEWEB)
Widhalm, Harald K.; Marlovits, Stefan; Vecsei, Vilmos [Medical University of Vienna, Center for Joints and Cartilage, Department of Traumatology, Vienna (Austria); Welsch, Goetz H. [Medical University of Vienna, MR Center, Department of Radiology, Vienna (Austria); University Hospital of Erlangen, Department of Trauma Surgery, Erlangen (Germany); Dirisamer, Albert [Medical University of Vienna, Department of Radiology, Vienna (Austria); Neuhold, Andreas [Private Hospital Rudolfinerhaus, Department of Radiology, Vienna (Austria); Griensven, Martijn van [Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna (Austria); Seemann, Rudolf [Medical University of Vienna, Department of Cranio-Maxillofacial and Oral Surgery, Vienna (Austria); Widhalm, Kurt [Medical University of Vienna, Division of Nutrition and Metabolism, Department of Pediatrics, Vienna (Austria)
2012-03-15
Overweight and obesity are afflictions that lead to an increased risk of health problems including joint problems. The aim of the study was to assess the condition of articular cartilage in obese adolescent patients suffering from knee pain. MRI of 24 knees of 20 morbidly obese patients, mean age 14.2 years, was performed in an open 1.0 Tesla MR system, where the cartilage, the quality and structure of the menisci, and the presence or absence of surrounding changes was examined. In all patients a cartilage lesion in at least one region of the knee could be detected. Retropatellar cartilage lesions have been found in 19 knees. Ten cartilage lesions grade I, and four lesions grade II have been described in the lateral compartment of the knee, whereas the medial compartment showed in eight cases a grade I, in 13 cases a grade II and in two cases a grade III cartilage lesion. Meniscal changes were assessed in most patients. Morbidly obese children and adolescents show major abnormalities in the articular cartilage of the knee. Whether obesity alone is the causal factor for the development of the pattern of these changes, remains to be seen. (orig.)
5. Obesity-related juvenile form of cartilage lesions: a new affliction in the knees of morbidly obese children and adolescents
International Nuclear Information System (INIS)
Overweight and obesity are afflictions that lead to an increased risk of health problems including joint problems. The aim of the study was to assess the condition of articular cartilage in obese adolescent patients suffering from knee pain. MRI of 24 knees of 20 morbidly obese patients, mean age 14.2 years, was performed in an open 1.0 Tesla MR system, where the cartilage, the quality and structure of the menisci, and the presence or absence of surrounding changes was examined. In all patients a cartilage lesion in at least one region of the knee could be detected. Retropatellar cartilage lesions have been found in 19 knees. Ten cartilage lesions grade I, and four lesions grade II have been described in the lateral compartment of the knee, whereas the medial compartment showed in eight cases a grade I, in 13 cases a grade II and in two cases a grade III cartilage lesion. Meniscal changes were assessed in most patients. Morbidly obese children and adolescents show major abnormalities in the articular cartilage of the knee. Whether obesity alone is the causal factor for the development of the pattern of these changes, remains to be seen. (orig.)
6. Atypical form of Alzheimer's disease with prominent posterior cortical atrophy: a review of lesion distribution and circuit disconnection in cortical visual pathways
Science.gov (United States)
Hof, P. R.; Vogt, B. A.; Bouras, C.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)
1997-01-01
In recent years, the existence of visual variants of Alzheimer's disease characterized by atypical clinical presentation at onset has been increasingly recognized. In many of these cases post-mortem neuropathological assessment revealed that correlations could be established between clinical symptoms and the distribution of neurodegenerative lesions. We have analyzed a series of Alzheimer's disease patients presenting with prominent visual symptomatology as a cardinal sign of the disease. In these cases, a shift in the distribution of pathological lesions was observed such that the primary visual areas and certain visual association areas within the occipito-parieto-temporal junction and posterior cingulate cortex had very high densities of lesions, whereas the prefrontal cortex had fewer lesions than usually observed in Alzheimer's disease. Previous quantitative analyses have demonstrated that in Alzheimer's disease, primary sensory and motor cortical areas are less damaged than the multimodal association areas of the frontal and temporal lobes, as indicated by the laminar and regional distribution patterns of neurofibrillary tangles and senile plaques. The distribution of pathological lesions in the cerebral cortex of Alzheimer's disease cases with visual symptomatology revealed that specific visual association pathways were disrupted, whereas these particular connections are likely to be affected to a less severe degree in the more common form of Alzheimer's disease. These data suggest that in some cases with visual variants of Alzheimer's disease, the neurological symptomatology may be related to the loss of certain components of the cortical visual pathways, as reflected by the particular distribution of the neuropathological markers of the disease.
7. 53BP1 nuclear bodies form around DNA lesions generated by mitotic transmission of chromosomes under replication stress
DEFF Research Database (Denmark)
Lukas, Claudia; Savic, Velibor; Bekker-Jensen, Simon;
2011-01-01
stress increases the frequency of chromosomal lesions that are transmitted to daughter cells. Throughout G1, these lesions are sequestered in nuclear compartments marked by p53-binding protein 1 (53BP1) and other chromatin-associated genome caretakers. We show that the number of such 53BP1 nuclear bodies...... increases after genetic ablation of BLM, a DNA helicase associated with dissolution of entangled DNA. Conversely, 53BP1 nuclear bodies are partially suppressed by knocking down SMC2, a condensin subunit required for mechanical stability of mitotic chromosomes. Finally, we provide evidence that 53BP1 nuclear...
8. Multifocal vascular lesions.
Science.gov (United States)
Levin, Laura E; Lauren, Christine T
2016-03-01
Multifocal vascular lesions are important to recognize and appropriately diagnose. Generally first noticed on the skin, multifocal vascular lesions may have systemic involvement. Distinguishing among the different types of multifocal vascular lesions is often based on clinical features; however, radiological imaging and/or biopsy are frequently needed to identify distinct features and guide treatment. Knowledge of the systemic associations that can occur with different vascular anomalies may reduce life-threatening complications, such as coagulopathy, bleeding, cardiac compromise, and neurologic sequelae. This review provides a synopsis of the epidemiology, pathogenesis, presentation, workup, and treatment of several well-recognized multifocal vascular tumors and malformations. PMID:27607324
9. [Cardiac amyloidosis].
Science.gov (United States)
Hoyer, Caroline; Angermann, Christiane E; Knop, Stefan; Ertl, Georg; Störk, Stefan
2008-03-15
Amyloidoses are a heterogeneous group of multisystem disorders, which are characterized by an extracellular deposition of amyloid fibrils. Typically affected are the heart, liver, kidneys, and nervous system. More than half of the patients die due to cardiac involvement. Clinical signs of cardiac amyloidosis are edema of the lower limbs, hepatomegaly, ascites and elevated jugular vein pressure, frequently in combination with dyspnea. There can also be chest pain, probably due to microvessel disease. Dysfunction of the autonomous nervous system or arrhythmias may cause low blood pressure, dizziness, or recurrent syncope. The AL amyloidosis caused by the deposition of immunoglobulin light chains is the most common form. It can be performed by monoclonal gammopathy. The desirable treatment therapy consists of high-dose melphalan therapy twice followed by autologous stem cell transplantation. Due to the high peritransplantation mortality, selection of appropriate patients is mandatory. The ATTR amyloidosis is an autosomal dominant disorder caused by the amyloidogenic form of transthyretin, a plasmaprotein that is synthesized in the liver. Therefore, liver transplantation is the only curative therapy. The symptomatic treatment of cardiac amyloidosis is based on the current guidelines for chronic heart failure according to the patient's New York Heart Association (NYHA) state. Further types of amyloidosis with possible cardiac involvement comprise the senile systemic amyloidosis caused by the wild-type transthyretin, secondary amyloidosis after chronic systemic inflammation, and the beta(2)-microglobulin amyloidosis after long-term dialysis treatment. PMID:18344065
10. Insights into the clinical and functional significance of cardiac autonomic dysfunction in Chagas disease
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Luiz Fernando Junqueira Junior
2012-04-01
Full Text Available INTRODUCTION: Exclusive or associated lesions in various structures of the autonomic nervous system occur in the chronic forms of Chagas disease. In the indeterminate form, the lesions are absent or mild, whereas in the exclusive or combined heart and digestive disease forms, they are often more pronounced. Depending on their severity these lesions can result mainly in cardiac parasympathetic dysfunction but also in sympathetic dysfunction of variable degrees. Despite the key autonomic effect on cardiovascular functioning, the pathophysiological and clinical significance of the cardiac autonomic dysfunction in Chagas disease remains unknown. METHODS: Review of data on the cardiac autonomic dysfunction in Chagas disease and their potential consequences, and considerations supporting the possible relationship between this disturbance and general or cardiovascular clinical and functional adverse outcomes. RESULTS: We hypothesise that possible consequences that cardiac dysautonomia might variably occasion or predispose in Chagas disease include: transient or sustained arrhythmias, sudden cardiac death, adverse overall and cardiovascular prognosis with enhanced morbidity and mortality, an inability of the cardiovascular system to adjust to functional demands and/or respond to internal or external stimuli by adjusting heart rate and other hemodynamic variables, and immunomodulatory and cognitive disturbances. CONCLUSIONS: Impaired cardiac autonomic modulation in Chagas disease might not be a mere epiphenomenon without significance. Indirect evidences point for a likely important role of this alteration as a primary predisposing or triggering cause or mediator favouring the development of subtle or evident secondary cardiovascular functional disturbances and clinical consequences, and influencing adverse outcomes.
11. Dogs infected with the blood trypomastigote form of Trypanosoma cruzi display an increase expression of cytokines and chemokines plus an intense cardiac parasitism during acute infection.
Science.gov (United States)
de Souza, Sheler Martins; Vieira, Paula Melo de Abreu; Roatt, Bruno Mendes; Reis, Levi Eduardo Soares; da Silva Fonseca, Kátia; Nogueira, Nívia Carolina; Reis, Alexandre Barbosa; Tafuri, Washington Luiz; Carneiro, Cláudia Martins
2014-03-01
The recent increase in immigration of people from areas endemic for Chagas disease (Trypanosoma cruzi) to the United States and Europe has raised concerns about the transmission via blood transfusion and organ transplants in these countries. Infection by these pathways occurs through blood trypomastigotes (BT), and these forms of T. cruzi are completely distinct of metacyclic trypomastigotes (MT), released by triatomine vector, in relation to parasite-host interaction. Thus, research comparing infection with these different infective forms is important for explaining the potential impacts on the disease course. Here, we investigated tissue parasitism and relative mRNA expression of cytokines, chemokines, and chemokine receptors in the heart during acute infection by MT or BT forms in dogs. BT-infected dogs presented a higher cardiac parasitism, increased relative mRNA expression of pro-inflammatory and immunomodulatory cytokines and of the chemokines CCL3/MIP-1α, CCL5/RANTES, and the chemokine receptor CCR5 during the acute phase of infection, as compared to MT-infected dogs. These results suggest that infection with BT forms may lead to an increased immune response, as revealed by the cytokines ratio, but this kind of immune response was not able to control the cardiac parasitism. Infection with the MT form presented an increase in the relative mRNA expression of IL-12p40 as compared to that of IL-10 or TGF-β1. Correlation analysis showed increased relative mRNA expression of IFN-γ as well as IL-10, which may be an immunomodulatory response, as well as an increase in the correlation of CCL5/RANTES and its CCR5 receptor. Our findings revealed a difference between inoculum sources of T. cruzi, as vectorial or transfusional routes of T. cruzi infection may trigger distinct parasite-host interactions during the acute phase, which may influence immunopathological aspects of Chagas disease.
12. Cardiac tumors: optimal cardiac MR sequences and spectrum of imaging appearances.
LENUS (Irish Health Repository)
O'Donnell, David H
2012-02-01
OBJECTIVE: This article reviews the optimal cardiac MRI sequences for and the spectrum of imaging appearances of cardiac tumors. CONCLUSION: Recent technologic advances in cardiac MRI have resulted in the rapid acquisition of images of the heart with high spatial and temporal resolution and excellent myocardial tissue characterization. Cardiac MRI provides optimal assessment of the location, functional characteristics, and soft-tissue features of cardiac tumors, allowing accurate differentiation of benign and malignant lesions.
13. Genetic Susceptibility to Cardiac and Digestive Clinical Forms of Chronic Chagas Disease: Involvement of the CCR5 59029 A/G Polymorphism.
Science.gov (United States)
de Oliveira, Amanda Priscila; Bernardo, Cássia Rubia; Camargo, Ana Vitória da Silveira; Ronchi, Luiz Sérgio; Borim, Aldenis Albaneze; de Mattos, Cinara Cássia Brandão; de Campos Júnior, Eumildo; Castiglioni, Lílian; Netinho, João Gomes; Cavasini, Carlos Eugênio; Bestetti, Reinaldo Bulgarelli; de Mattos, Luiz Carlos
2015-01-01
The clinical manifestations of chronic Chagas disease include the cardiac form of the disease and the digestive form. Not all the factors that act in the variable clinical course of this disease are known. This study investigated whether the CCR5Δ32 (rs333) and CCR5 59029 A/G (promoter region--rs1799987) polymorphisms of the CCR5 gene are associated with different clinical forms of chronic Chagas disease and with the severity of left ventricular systolic dysfunction in patients with chronic Chagas heart disease (CCHD). The antibodies anti-T. cruzi were identified by ELISA. PCR and PCR-RFLP were used to identify the CCR5Δ32 and CCR5 59029 A/G polymorphisms. The chi-square test was used to compare variables between groups. There was a higher frequency of the AA genotype in patients with CCHD compared with patients with the digestive form of the disease and the control group. The results also showed a high frequency of the AG genotype in patients with the digestive form of the disease compared to the other groups. The results of this study show that the CCR5Δ32 polymorphism does not seem to influence the different clinical manifestations of Chagas disease but there is involvement of the CCR5 59029 A/G polymorphism in susceptibility to the different forms of chronic Chagas disease. Besides, these polymorphisms do not influence left ventricular systolic dysfunction in patients with CCHD.
14. Genetic Susceptibility to Cardiac and Digestive Clinical Forms of Chronic Chagas Disease: Involvement of the CCR5 59029 A/G Polymorphism.
Directory of Open Access Journals (Sweden)
Amanda Priscila de Oliveira
Full Text Available The clinical manifestations of chronic Chagas disease include the cardiac form of the disease and the digestive form. Not all the factors that act in the variable clinical course of this disease are known. This study investigated whether the CCR5Δ32 (rs333 and CCR5 59029 A/G (promoter region--rs1799987 polymorphisms of the CCR5 gene are associated with different clinical forms of chronic Chagas disease and with the severity of left ventricular systolic dysfunction in patients with chronic Chagas heart disease (CCHD. The antibodies anti-T. cruzi were identified by ELISA. PCR and PCR-RFLP were used to identify the CCR5Δ32 and CCR5 59029 A/G polymorphisms. The chi-square test was used to compare variables between groups. There was a higher frequency of the AA genotype in patients with CCHD compared with patients with the digestive form of the disease and the control group. The results also showed a high frequency of the AG genotype in patients with the digestive form of the disease compared to the other groups. The results of this study show that the CCR5Δ32 polymorphism does not seem to influence the different clinical manifestations of Chagas disease but there is involvement of the CCR5 59029 A/G polymorphism in susceptibility to the different forms of chronic Chagas disease. Besides, these polymorphisms do not influence left ventricular systolic dysfunction in patients with CCHD.
15. Giant Cardiac Cavernous Hemangioma.
Science.gov (United States)
Unger, Eric; Costic, Joseph; Laub, Glenn
2015-07-01
We report the case of an asymptomatic giant cardiac cavernous hemangioma in a 71-year-old man. The intracardiac mass was discovered incidentally during surveillance for his prostate cancer; however, the patient initially declined intervention. On presentation to our institution 7 years later, the lesion had enlarged significantly, and the patient consented to excision. At surgery, an 8 × 6.5 × 4.8 cm intracardiac mass located on the inferior heart border was excised with an intact capsule through a median sternotomy approach. The patient had an uneventful postoperative course. We discuss the diagnostic workup, treatment, and characteristics of this rare cardiac tumor. PMID:26140782
16. Combined Therapeutic and Monitoring Ultrasonic Catheter for Cardiac Ablation Therapies.
Science.gov (United States)
Carias, Mathew; Hynynen, Kullervo
2016-01-01
This study evaluated the feasibility of a combined therapeutic and diagnostic ultrasonic catheter for cardiac ablation therapies. Ultrasound can be used to determine when diseased cardiac tissues have become fully coagulated through a method known as local harmonic motion imaging (LHMI). LHMI is an imaging modality for treatment monitoring that uses acoustic radiation force, displacement tracking and the different mechanical properties of viable and ablated tissues. In this study, we developed catheters that are capable of LHMI measurements. Experiments were conducted in phantoms, ex vivo cardiac samples and the in vivo beating hearts of healthy porcine subjects. In vivo experiments revealed that four of four epicardial sonications revealed a decrease in measured displacements from LHMI experiments and that when lower power was used, no lesions formed and there was no corresponding decrease in measured displacement amplitudes. In addition, two of three endocardial lesions were confirmed and corresponded to a decrease in the measured displacement amplitude. PMID:26431798
17. Cardiac arrest
Science.gov (United States)
... Article.jsp. Accessed June 16, 2014. Myerburg RJ, Castellanos A. Approach to cardiac arrest and life-threatening ... PA: Elsevier Saunders; 2011:chap 63. Myerburg RJ, Castellanos A. Cardiac arrest and audden aardiac death. In: ...
18. Severe form of radiculo - myelo - neuropathy with meningo - encephalitis secondary to Angiostrongylus cantonensis infection: unusual corpus callosal lesions and serial magnetic resonance imaging findings.
Science.gov (United States)
Nalini, Atchayaram; Ramakrishna, Anil; Dekumoy, Paron; Kumar, Raju Ravi; Pakdee, Wallop; Saini, Jitender; Hegde, Vinay S
2013-01-01
A 43-year-old man presented with the symptoms of recurrent lower abdominal pain, malaise and loss of appetite of 3-week duration, followed by acute onset of generalized paresthesias, fever and headache which progressed over few days to quadriparesis, altered sensorium, urinary and fecal incontinence. He had consumed raw tongue, liver, gall bladder and testicles of monitor lizard (Varanus bengalensis). Blood picture showed eosinophilia and cerebrospinal fluid (CSF) analysis revealed elevated protein and eosinophilia. Serum and CSF serology was positive for angiostrongyliasis. Magnetic resonance imaging showed focal hyperintense lesions in the corpus callosum and brainstem and an enhancing lesion in the cerebellum. Post-contrast T1-weighted axial images of spine showed evidence of cervical cord hyperintense lesions and root enhancement. Susceptibility weighted images/phase images showed unusual feature of multiple hemorrhagic lesions in the posterior fossa and supratentorial areas. Diffusion showed no restriction of corpus callosal lesions. Patient was treated with the high dose parenteral steroids with albendazole and at 6-month follow-up and had a remarkable recovery. PMID:24005735
19. Epidermodisplasia verruciforme: apresentação clínica com variadas formas de lesões Epidermodysplasia verruciformis: clinical presentation with varied forms of lesions
Directory of Open Access Journals (Sweden)
Naiana Bittencourt de Sá
2011-08-01
Full Text Available Epidermodisplasia verruciforme é uma genodermatose rara caracterizada por infecção disseminada por HPV, de caráter recessivo, com casos ligados ao cromossoma X. É caracterizada clinicamente por lesões maculares hipo ou hiperpigmentadas, lesões pitiríase versicolor like, verrugas planas e desenvolvimento precoce de carcinomas cutâneos. Descreve-se um caso de paciente com quadro clínico exuberante, apresentando todas as formas de lesões desta doença, inclusive presença de carcinoma espinocelular agressivo na faceEpidermodysplasia verruciformis is a rare inherited skin disorder spread by HPV, with cases linked to chromosome X. It is characterized by hypo- or hyper-pigmented macular lesions, pityriasis versicolor-like lesions and an early tendency to develop skin malignancies. We present a case of epidermodysplasia verruciformis with a variety of lesions such as multiple plane warts, pityriasis versicolor-like lesions and aggressive squamous cell carcinoma on the face
20. Evolução e reversibilidade das lesões neurológicas e cardíacas em ovinos intoxicados experimentalmente por Ateleia glazioviana e Tetrapterys multiglandulosa Evolution and reversibility of neurologic and cardiac lesions in sheep caused by Ateleia glazioviana and Tetrapterys multiglandulosa
Directory of Open Access Journals (Sweden)
Milton B. Almeida
2008-03-01
podem ocorrer sinais nervosos sem evidências de lesões cardíacas.To determine the reversibility of neurological and cardiac lesions in Ateleia glazioviana and Tetrapterys multiglandulosa poisoning, 3 groups of four sheep each were fed orally with the plants. In Group 1, 2 and 3, when sheep with nervous signs showed considerable increase of symptoms and risk of death, the plant administration was suspended. Group 4 with two sheep was used as control. Sheep from Group 1, fed 10g/kg during 6 days of fresh A. glazioviana collected in autumn were euthanized 8, 11, 16, and 21 days after the start of the experiment; they had shown regression of nervous signs, but had progressive cardiac lesions. Sheep from Group 2, fed during 8 days the same dose of fresh A. glazioviana collected in spring, were euthanized on days 9, 23, 38 and 68; they had shown regression of nervous signs and had no cardiac lesions. This suggests that the plant is less toxic in spring. Sheep from Group 3, fed 10g/kg during 11 days dry and ground T. multiglandulosa mixed with concentrated food, were euthanized on days 33, 33, 92 and 92; they had shown regression of nervous signs, and cardiac lesions were less severe on day 33 than on day 92. These results indicate that nervous lesions are reversible after the end of feeding, but cardiac lesions are progressive after discontinuation of the plant administration; these can be afterwards reversible if the animals do not anymore show clinical signs or die as a consequence of the poisoning. Results of those and previous experiments show that lesions of the nervous system are induced by lower doses than cardiac lesions and occur within a shorter period, what suggests that in spontaneous cases cardiac signs are always preceded by nervous signs, and that nervous signs can occur in the absence of cardiac lesions.
1. Magnetic Resonance Imaging of Benign Cardiac Masses: A Pictorial Essay
Directory of Open Access Journals (Sweden)
Thomas J Ward
2013-01-01
Full Text Available The differential diagnosis for a cardiac mass includes primary and metastatic neoplasms. While primary cardiac tumors are rare, metastatic disease to the heart is a common finding in cancer patients. Several "tumor-like" processes can mimic a true cardiac neoplasm with accurate diagnosis critical at guiding appropriate management. We present a pictorial essay of the most common benign cardiac masses and "mass-like" lesions with an emphasis on magnetic resonance imaging features.
2. IS CONSANGUINEOUS MARRIAGE RESPONSIBLE FOR CONGENITAL CARDIAC AND EXTRA-CARDIAC ANOMALIES?
OpenAIRE
Nutan Nalini; Sudha
2016-01-01
BACKGROUND This article is about the stillbirth in which we found significant numbers of cardiac as well as extracardiac defects, in combination or separately. In this article, we would like to emphasize the anomalies found in consanguineous marriages. AIM To correlate the prevalence of cardiac as well as extracardiac anomalies in consanguineous marriages. Especially, here we would like to focus on the cardiac lesions. MATERIAL AND METHOD The study was ca...
3. Hematoma disecante intramiocárdico: una forma poco frecuente de rotura cardíaca Intramyocardial dissecting haematoma: an unusual form of cardiac rupture
Directory of Open Access Journals (Sweden)
F.J. García Fernández
2003-08-01
Full Text Available El hematoma disecante intramiocárdico es una complicación mecánica del infarto agudo de miocardio que consiste en la formación de una neocavitación causada por la disección hemorrágica entre las fibras espirales miocárdicas y que se encuentra contenida dentro del miocardio. Es una rotura de pared libre que aparece en el 9% de las autopsias de roturas cardíacas postinfarto. Su diagnóstico es complejo y aparece en la mayor parte de los pacientes "postmortem". Comentamos el caso de un paciente de 69 años que sufrió un infarto posterolateral y fue tratado con angioplastia primaria/ stent en las primeras horas así como con ácido acetil salicílico, clopidogrel, heparina sódica y antagonistas de GPIIb-IIIa. En las siguientes horas presentó esta rara forma de rotura cardíaca que le llevó al shock cardiogénico y le causó la muerte. Se revisa la fisiopatología, diagnóstico y manejo de esta entidad que presenta una alta letalidad (90% en los pacientes tratados médicamente y cuyo único tratamiento es la cirugía.The intramyocardial dissecting haematoma is an unusual rupture of the left ventricular wall, complicating acute myocardial infarction. The mechanism is an hemorrhagic dissection among the spiral myocardial fibres creating a neocavitation limited by the myocardium. It appears in 9% of left ventricular wall ruptures, complicating acute myocardial infarction. Diagnosis is often difficult and in most of the cases it is post-mortem. We present the case report of a 69 year old patient who suffered a posterolateral acute myocardial infarction treated with primary PTCA/Stent plus AAS, clopidogrel, unfractioned heparin bolus and GP IIb- IIIa inhibitors. In the following few hours he suffered this unusual form of cardiac rupture that took him into cardiogenic shock and finally led to his death. The pathophysiology, diagnosis and management of this lethal complication of acute myocardial infarction (90% mortality in the medically
4. Increased expression of phosphorylated forms of heat-shock protein-27 and p38MAPK in macrophage-rich regions of fibro-fatty atherosclerotic lesions in the rabbit.
Science.gov (United States)
Shafi, Shahida; Codrington, Rosalind; Gidden, Lewis Michael; Ferns, Gordon Ashley Anthony
2016-02-01
We aimed to assess the expression and distribution of Hsp27, pHsp27 (Ser82), p38MAPK and p-p38MAPK in fibro-fatty atherosclerotic lesions and the myocardium of hypercholesterolaemic rabbits. Male New Zealand white rabbits were fed a high-cholesterol diet for 18 weeks, maintaining serum cholesterol at approximately 20 mmol/l over this period. Aortic arch and myocardial tissues were analysed by Western blot, immunohistochemistry and double immunofluorescence. Plasma Hsp27 levels were measured by ELISA. There was a significant increase in the expression of monomeric and dimeric forms of Hsp27, together with pHsp27 (Ser82), p38MAPK and p-p38MAPK in the fibro-fatty atherosclerotic lesions (P < 0.01; P < 0.05; P < 0.001; and P < 0.001, respectively) and the myocardial tissues (P < 0.001) from the cholesterol-fed rabbits compared with equivalent tissues from controls when the plasma concentration was low. Immunohistochemical analysis of the fibro-fatty lesions showed marked increases in Hsp27 and pHsp27 (Ser82) immunoreactivity. Double immunostaining showed intense expression of pHsp27 and p-p38MAPK in regions that were rich in macrophages, suggesting a close association with these inflammatory cells, whereas, in regions rich in smooth muscle cells, only p-p38MAPK was found to be strongly expressed. An increased expression of pHsp27 (Ser82) was spatially associated with increased p-p38MAPK within fibro-fatty atherosclerotic lesions and was colocalized to regions rich in macrophages. The initial increase in plasma Hsp27 levels may reflect the increase in systemic inflammation and oxidative stress in the early phases of disease. The falling concentrations subsequently may be coincident with the development of the advanced atherosclerotic lesions.
5. An overview of cardiac morphogenesis.
Science.gov (United States)
Schleich, Jean-Marc; Abdulla, Tariq; Summers, Ron; Houyel, Lucile
2013-11-01
Accurate knowledge of normal cardiac development is essential for properly understanding the morphogenesis of congenital cardiac malformations that represent the most common congenital anomaly in newborns. The heart is the first organ to function during embryonic development and is fully formed at 8 weeks of gestation. Recent studies stemming from molecular genetics have allowed specification of the role of cellular precursors in the field of heart development. In this article we review the different steps of heart development, focusing on the processes of alignment and septation. We also show, as often as possible, the links between abnormalities of cardiac development and the main congenital heart defects. The development of animal models has permitted the unraveling of many mechanisms that potentially lead to cardiac malformations. A next step towards a better knowledge of cardiac development could be multiscale cardiac modelling. PMID:24138816
6. Cardiac rehabilitation
Science.gov (United States)
... attack or other heart problem. You might consider cardiac rehab if you have had: Heart attack Coronary heart disease (CHD) Heart failure Angina (chest pain) Heart or heart valve surgery Heart transplant Procedures such as angioplasty and stenting In some ...
7. Interventional cardiac catheterization.
Science.gov (United States)
Pihkala, J; Nykanen, D; Freedom, R M; Benson, L N
1999-04-01
Over the past decade, transcatheter interventions have become increasingly important in the treatment of patients with congenital heart lesions. These procedures may be broadly grouped as dilations (e.g., septostomy, valvuloplasty, angioplasty, and endovascular stenting) or as closures (e.g., vascular embolization and device closure of defects). Balloon valvuloplasty has become the treatment of choice for patients in all age groups with simple valvar pulmonic stenosis and, although not curative, seems at least comparable to surgery for congenital aortic stenosis in newborns to young adults. Balloon angioplasty is successfully applied to a wide range of aortic, pulmonary artery, and venous stenoses. Stents are useful in dilating lesions of which the intrinsic elasticity results in vessel recoil after balloon dilation alone. Catheter-delivered coils are used to embolize a wide range of arterial, venous, and prosthetic vascular connections. Although some devices remain investigational, they have been successfully used for closure of many arterial ducts and atrial and ventricular septal defects. In the therapy for patients with complex CHD, best results may be achieved by combining cardiac surgery with interventional catheterization. The cooperation among interventional cardiologists and cardiac surgeons was highlighted in a report of an algorithm to manage patients with tetralogy of Fallot or pulmonary atresia with diminutive pulmonary arteries, involving balloon dilation, coil embolization of collaterals, and intraoperative stent placement. In this setting, well-planned catheterization procedures have an important role in reducing the overall number of procedures that patients may require over a lifetime, with improved outcomes.
8. Rescue of hereditary form of dilated cardiomyopathy by rAAV-mediated somatic gene therapy: Amelioration of morphological findings, sarcolemmal permeability, cardiac performances, and the prognosis of TO-2 hamsters
OpenAIRE
Kawada, Tomie; Nakazawa, Mikio; Nakauchi, Sakura; YAMAZAKI, Ken; Shimamoto, Ryoichi; Urabe, Masashi; Nakata, Jumi; Hemmi, Chieko; Masui, Fujiko; Nakajima, Toshiaki; Suzuki, Jun-ichi; Monahan, John; Sato, Hiroshi; Masaki, Tomoh; Ozawa, Keiya
2002-01-01
The hereditary form comprises ≈1/5 of patients with dilated cardiomyopathy (DCM) and is a major cause of advanced heart failure. Medical and socioeconomic settings require novel treatments other than cardiac transplantation. TO-2 strain hamsters with congenital DCM show similar clinical and genetic backgrounds to human cases that have defects in the δ-sarcoglycan (δ-SG) gene. To examine the long-term in vivo supplement of normal δ-SG gene driven by cytomegalovirus promoter, we analyzed the pa...
9. Plaque vulnerability of coronary artery lesions is related to left ventricular dilatation as determined by optical coherence tomography and cardiac magnetic resonance imaging in patients with type 2 diabetes
OpenAIRE
Burgmaier, Mathias; Frick, Michael; Liberman, Ana; Battermann, Simone; Hellmich, Martin; Lehmacher, Walter; Jaskolka, Agnes; Marx, Nikolaus; Reith, Sebastian Berthold
2013-01-01
Background Patients with type 2 diabetes are at increased risk for both, left ventricular (LV)-dilatation and myocardial infarction (MI) following the rupture of a vulnerable plaque. This study investigated the to date incompletely understood relationship between plaque vulnerability and LV-dilatation using optical coherence tomography (OCT) and cardiac magnetic resonance imaging (CMR) in patients with type 2 diabetes and stable coronary artery disease. Methods CMR was performed in 58 patient...
10. Microwave Treatment for Cardiac Arrhythmias
Science.gov (United States)
Hernandez-Moya, Sonia
2009-01-01
NASA seeks to transfer the NASA developed microwave ablation technology, designed for the treatment of ventricular tachycardia (irregular heart beat), to industry. After a heart attack, many cells surrounding the resulting scar continue to live but are abnormal electrically; they may conduct impulses unusually slowly or fire when they would typically be silent. These diseased areas might disturb smooth signaling by forming a reentrant circuit in the muscle. The objective of microwave ablation is to heat and kill these diseased cells to restore appropriate electrical activity in the heart. This technology is a method and apparatus that provides for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna is effective for this purpose over a bandwidth of about six gigahertz. A computer simulation provides initial screening capabilities for an antenna such as antenna, frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In comparison with other methods that involve direct-current pulses or radio frequencies below 1 GHz, this method may prove more effective in treating ventricular tachycardia. This is because the present method provides for greater control of the location, cross-sectional area, and depth of a lesion via selection of the location and design of the antenna and the choice of microwave power and frequency.
11. Scintigraphic differentiation between two forms of primary dysautonomia early after onset of autonomic dysfunction: value of cardiac and pulmonary iodine-123 MIBG uptake
International Nuclear Information System (INIS)
Primary dysfunction of the autonomic nervous system can be observed in patients with Parkinson's disease and those with multiple system atrophy. However, the fate of the two diseases differs considerably and leads to different strategies for patient management. Differentiation of the two diseases currently requires a combination of several clinical and electrophysiological tests. First studies of myocardial innervation using iodine-123 metaiodobenzylguanidine (MIBG) indicated a possible role of scintigraphy for this purpose. An increase in the pulmonary uptake of 123I-MIBG has been reported in secondary dysautonomias. Whether sympathetic innervation of the lung is affected in primary dysautonomias is currently unknown. Therefore, cardiac and pulmonary uptake of 123I-MIBG was studied in 21 patients with Parkinson's disease, 7 patients with multiple system atrophy and 13 age- and sex-matched controls. Thoracic images were obtained in the anterior view 4 h after intravenous injection of 185 MBq 123I-MIBG, at which time the maximum neuronal uptake is reached. All patients with Parkinson's disease had significantly lower cardiac uptake of 123I-MIBG than patients with multiple system atrophy and controls. Sympathetic innervation of the lung was not affected in either disease. It is concluded that scintigraphy with 123I-MIBG appears to be a useful tool for differentiation between Parkinson's disease and multiple system atrophy early after onset of autonomic dysfunction. (orig.)
12. Scintigraphic differentiation between two forms of primary dysautonomia early after onset of autonomic dysfunction: value of cardiac and pulmonary iodine-123 MIBG uptake
Energy Technology Data Exchange (ETDEWEB)
Reinhardt, M.J.; Juengling, F.D.; Krause, T.M. [Dept. of Nuclear Medicine, Freiburg University Hospital (Germany); Braune, S. [Dept. of Neurology, Freiburg University Hospital (Germany)
2000-05-01
Primary dysfunction of the autonomic nervous system can be observed in patients with Parkinson's disease and those with multiple system atrophy. However, the fate of the two diseases differs considerably and leads to different strategies for patient management. Differentiation of the two diseases currently requires a combination of several clinical and electrophysiological tests. First studies of myocardial innervation using iodine-123 metaiodobenzylguanidine (MIBG) indicated a possible role of scintigraphy for this purpose. An increase in the pulmonary uptake of {sup 123}I-MIBG has been reported in secondary dysautonomias. Whether sympathetic innervation of the lung is affected in primary dysautonomias is currently unknown. Therefore, cardiac and pulmonary uptake of {sup 123}I-MIBG was studied in 21 patients with Parkinson's disease, 7 patients with multiple system atrophy and 13 age- and sex-matched controls. Thoracic images were obtained in the anterior view 4 h after intravenous injection of 185 MBq {sup 123}I-MIBG, at which time the maximum neuronal uptake is reached. All patients with Parkinson's disease had significantly lower cardiac uptake of {sup 123}I-MIBG than patients with multiple system atrophy and controls. Sympathetic innervation of the lung was not affected in either disease. It is concluded that scintigraphy with {sup 123}I-MIBG appears to be a useful tool for differentiation between Parkinson's disease and multiple system atrophy early after onset of autonomic dysfunction. (orig.)
13. Cardiac CT
Energy Technology Data Exchange (ETDEWEB)
Dewey, Marc [Charite - Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie
2011-07-01
Computed tomography of the heart has become a highly accurate diagnostic modality that is attracting increasing attention. This extensively illustrated book aims to assist the reader in integrating cardiac CT into daily clinical practice, while also reviewing its current technical status and applications. Clear guidance is provided on the performance and interpretation of imaging using the latest technology, which offers greater coverage, better spatial resolution, and faster imaging. The specific features of scanners from all four main vendors, including those that have only recently become available, are presented. Among the wide range of applications and issues to be discussed are coronary artery bypass grafts, stents, plaques, and anomalies, cardiac valves, congenital and acquired heart disease, and radiation exposure. Upcoming clinical uses of cardiac CT, such as plaque imaging and functional assessment, are also explored. (orig.)
14. Cardiac echinococcosis
Directory of Open Access Journals (Sweden)
Ivanović-Krstić Branislava A.
2002-01-01
Full Text Available Cardiac hydatid disease is rare. We report on an uncommon hydatid cyst localized in the right ventricular wall, right atrial wall tricuspid valve left atrium and pericard. A 33-year-old woman was treated for cough, fever and chest pain. Cardiac echocardiograpic examination revealed a round tumor (5.8 x 4 cm in the right ventricular free wall and two smaller cysts behind that tumor. There were cysts in right atrial wall and tricuspidal valve as well. Serologic tests for hydatidosis were positive. Computed tomography finding was consistent with diagnosis of hydatid cyst in lungs and right hylar part. Surgical treatment was rejected due to great risk of cardiac perforation. Medical treatment with albendazole was unsuccessful and the patient died due to systemic hydatid involvement of the lungs, liver and central nervous system.
15. Metastatic Breast Cancer or Multiple Myeloma? Camouflage by Lytic Lesions
OpenAIRE
Bruce Hough; Adam Brufsky; Suzanne Lentzsch
2010-01-01
We report a case of a female with stage I infiltrating ductal carcinoma who received adjuvant therapy including trastuzumab. One year later she developed lytic lesions and was retreated with trastuzumab that was held after she developed symptomatic heart failure. Lytic lesions were attributed to relapse of breast cancer, and cardiac failure attributed to prior trastuzumab therapy. After complications necessitated multiple hospitalizations, a further workup revealed that the lytic lesions were...
16. An overview of cardiac morphogenesis.
OpenAIRE
Schleich, Jean-Marc; Abdulla, Tariq; Summers, Ron; Houyel, Lucile
2013-01-01
International audience Accurate knowledge of normal cardiac development is essential for properly understanding the morphogenesis of congenital cardiac malformations that represent the most common congenital anomaly in newborns. The heart is the first organ to function during embryonic development and is fully formed at 8 weeks of gestation. Recent studies stemming from molecular genetics have allowed specification of the role of cellular precursors in the field of heart development. In th...
17. Cardiac rhabdomyosarcoma
OpenAIRE
Chlumský, Jaromír; Holá, Dana; Hlaváček, Karel; Michal, Michal; Švec, Alexander; Špatenka, Jaroslav; Dušek, Jan
2001-01-01
Cardiac sarcoma is a very rare neoplasm and is difficult to diagnose. The case of a 51-year-old man with a left atrial tumour, locally recurrent three months after its surgical removal, is presented. Computed tomography showed metastatic spread to the lung parenchyma. On revised histology, the mass extirpated was a sarcoma. Because of the metastatic spread, further therapy was symptomatic only; the patient died 15 months after the first manifestation of his problems. Immunohistochemical stain...
18. CARDIAC TRANSPLANTATION: AN ANESTHETIC CHALLENGE
OpenAIRE
Premalatha; Jayaraman,
2014-01-01
: Heart transplantation has emerged as the definitive therapy for patients with end-stage cardiomyopathy. The two most common forms of cardiac disease that lead to transplantation are ischemic cardiomyopathy and dilated cardiomyopathy, which together comprise approximately 90% of cases. The other less common forms of heart disease include viral cardiomyopathy, infiltrative cardiomyopathy, postpartum cardiomyopathy, valvular heart disease and congenital heart disease
19. Percutaneous coronary angioplasty in a cardiac transplant recipient.
OpenAIRE
Gammage, M D; Shiu, M F; English, T A
1988-01-01
Two years after an orthotopic cardiac transplant a 28 year old man was found to have clinically significant stenosis of the right coronary artery at routine coronary angiography. This lesion was accompanied by a perfusion defect on exercise thallium scintigraphy. Percutaneous transluminal coronary angioplasty of the lesion improved the angiographic appearance of the stenosis and reduced the exercise thallium perfusion defect.
20. Photoacoustic characterization of radiofrequency ablation lesions
Science.gov (United States)
Bouchard, Richard; Dana, Nicholas; Di Biase, Luigi; Natale, Andrea; Emelianov, Stanislav
2012-02-01
Radiofrequency ablation (RFA) procedures are used to destroy abnormal electrical pathways in the heart that can cause cardiac arrhythmias. Current methods relying on fluoroscopy, echocardiography and electrical conduction mapping are unable to accurately assess ablation lesion size. In an effort to better visualize RFA lesions, photoacoustic (PA) and ultrasonic (US) imaging were utilized to obtain co-registered images of ablated porcine cardiac tissue. The left ventricular free wall of fresh (i.e., never frozen) porcine hearts was harvested within 24 hours of the animals' sacrifice. A THERMOCOOLR Ablation System (Biosense Webster, Inc.) operating at 40 W for 30-60 s was used to induce lesions through the endocardial and epicardial walls of the cardiac samples. Following lesion creation, the ablated tissue samples were placed in 25 °C saline to allow for multi-wavelength PA imaging. Samples were imaged with a VevoR 2100 ultrasound system (VisualSonics, Inc.) using a modified 20-MHz array that could provide laser irradiation to the sample from a pulsed tunable laser (Newport Corp.) to allow for co-registered photoacoustic-ultrasound (PAUS) imaging. PA imaging was conducted from 750-1064 nm, with a surface fluence of approximately 15 mJ/cm2 maintained during imaging. In this preliminary study with PA imaging, the ablated region could be well visualized on the surface of the sample, with contrasts of 6-10 dB achieved at 750 nm. Although imaging penetration depth is a concern, PA imaging shows promise in being able to reliably visualize RF ablation lesions.
1. CENTRAL AMYGDALA LESIONS AFFECT BEHAVIORAL AND AUTONOMIC BALANCE DURING STRESS IN RATS
OpenAIRE
Roozendaal, B.; Koolhaas, JM; Bohus, B
1991-01-01
The effects of a bilateral electrolytical lesion of the CEA on the behavioral and sympathetically induced cardiac response in the shock-probe/defensive-burying test have been analyzed in male Wistar rats. Lesions in the CEA failed to affect defensive burying and accompanying tachycardiac response as compared to sham-lesioned controls during the presentation of the electrified shock probe (unconditioned test). However, CEA lesioning attenuated the bradycardiac response and the immobility behav...
2. Cardiac involvement in Erdheim- Chester disease: MRI findings and literature revision
International Nuclear Information System (INIS)
Erdheim-Chester disease (ECD) is a rare form of non-Langerhans cell histiocytosis, characterized by the involvement of several organs. The lesions may be skeletal or extra-skeletal: in particular, long bones, skin, lungs, and the cardiovascular and the central nervous systems can be affected. In this report, we describe a case of a 34-year-old man, who came to our observation with symptomatic ECD, for a correct assessment of the degree of cardiac involvement through magnetic resonance imaging (MRI)
3. Study on the effect of collateral circulation on cardiac function in patients receiving percutaneous coronary intervention(PCI)for le-sions in single left anterior descending artery%侧支循环对前降支单支病变冠心病PCI手术患者心脏功能影响的研究
Institute of Scientific and Technical Information of China (English)
王微; 孟亮; 田志鹏; 赵鑫
2015-01-01
Objective To explore the effect of establishment of collateral circulation on cardiac function in patients receiving percutaneous coronary intervention( PCI)for treatment of lesions in single left anterior descending artery. Methods The clinical data of 284 patients receiving PCI for treatment of lesions in single left anterior descending artery during January 2012 to June 2014 were retrospectively analyzed. These patients were divided into without collateral circulation group(group A,Rentrop grade 0,n=150)and collateral circulation group(group B,Rentrop grades 1,2 and 3,n=134)according to the results of coronary angiography. The above-mentioned 134 patients were further divided into insilat-eral group(group B1,n=20),contralateral group(group B2,n=91)and insilateral﹢contralateral group(group B3,n=23)according to the source of collateral circulation. LVEDD,LVEDS,LVEF,E/A and plasma level of BNP were compared among all these groups immediately,1 month,3 and 6 months after operation. Results Postoperative cardiac function in all patients had been improved,but LVEDD,LVESD and plas-ma level of BNP in patients of group B were significantly lower than those of patients in group A( P ﹤0. 05),while LVEF and E/A were signifi-cantly higher than those of patients in group A( P ﹤0. 05). Among patients in group B,postoperative cardiac function of patients in group B3 was the best,followed by patients in group B2,and that of patients in group B1 was the worst. Conclusion The establishment of collateral circulation can significantly improve the cardiac function of patients receiving PC intervention in a single left anterior descending artery. Postoperative cardiac function of patients with insilateral﹢contralateral collateral circulation is the best,followed by cases with contralateral collateral circulation. The postoperative cardiac function in patients with insilateral collateral circulation is the worst.%目的：探讨侧支循环对前降支单支病变冠
4. Cardiac autonomic nerve distribution and arrhythmia
Institute of Scientific and Technical Information of China (English)
Quan Liu; Dongmei Chen; Yonggang Wang; Xin Zhao; Yang Zheng
2012-01-01
OBJECTIVE: To analyze the distribution characteristics of cardiac autonomic nerves and to explore the correlation between cardiac autonomic nerve distribution and arrhythmia.DATA RETRIEVAL: A computer-based retrieval was performed for papers examining the distribution of cardiac autonomic nerves, using "heart, autonomic nerve, sympathetic nerve, vagus nerve, nerve distribution, rhythm and atrial fibrillation" as the key words.SELECTION CRITERIA: A total of 165 studies examining the distribution of cardiac autonomic nerve were screened, and 46 of them were eventually included.MAIN OUTCOME MEASURES: The distribution and characteristics of cardiac autonomic nerves were observed, and immunohistochemical staining was applied to determine the levels of tyrosine hydroxylase and acetylcholine transferase (main markers of cardiac autonomic nerve distribution). In addition, the correlation between cardiac autonomic nerve distribution and cardiac arrhythmia was investigated.RESULTS: Cardiac autonomic nerves were reported to exhibit a disordered distribution in different sites, mainly at the surface of the cardiac atrium and pulmonary vein, forming a ganglia plexus. The distribution of the pulmonary vein autonomic nerve was prominent at the proximal end rather than the distal end, at the upper left rather than the lower right, at the epicardial membrane rather than the endocardial membrane, at the left atrium rather than the right atrium, and at the posterior wall rather than the anterior wall. The main markers used for cardiac autonomic nerves were tyrosine hydroxylase and acetylcholine transferase. Protein gene product 9.5 was used to label the immunoreactive nerve distribution, and the distribution density of autonomic nerves was determined using a computer-aided morphometric analysis system.CONCLUSION: The uneven distribution of the cardiac autonomic nerves is the leading cause of the occurrence of arrhythmia, and the cardiac autonomic nerves play an important role in the
5. Visceral leishmaniasis with cardiac involvement in a dog: a case report
Directory of Open Access Journals (Sweden)
Goicoa Ana
2009-04-01
Full Text Available Abstract A dog presented with cutaneous nodules, enlarged lymph nodes and oedema in limbs, face and abdomen. The diagnosis of visceral leishmaniasis was established by identification of Leishmania amastigotes within macrophages from skin and popliteal lymph node biopsies. At necropsy, lesions were found in different organs, but it was particularly striking to observe large areas of pallor in the myocardium. Histological examination revealed an intense chronic inflammatory reaction in many organs, and numerous macrophages were found to contain amastigote forms of Leishmania. The inflammatory reaction was especially severe in the heart, where large areas of the myocardium appeared infiltrated with huge numbers of mononuclear immune cells, causing cardiac muscle atrophy and degeneration. Despite the severe inflammation, the number of parasitized macrophages was low in the myocardium, as revealed by immunohistochemical staining of Leishmania amastigotes. Because cardiac involvement is not usually described in this condition, this dog represents a very rare case of canine visceral leishmaniasis with affection of the myocardium.
6. Cardiac MRI in Athletes
NARCIS (Netherlands)
Luijkx, T.
2012-01-01
Cardiac magnetic resonance imaging (CMR) is often used in athletes to image cardiac anatomy and function and is increasingly requested in the context of screening for pathology that can cause sudden cardiac death (SCD). In this thesis, patterns of cardiac adaptation to sports are investigated with C
7. Relationship between cardiac function and resting cerebral blood flow
DEFF Research Database (Denmark)
Henriksen, Otto M; Jensen, Lars T; Krabbe, Katja;
2014-01-01
a gender-related inverse association of increased low-to-high-frequency power ratio with CBF and fractional brain flow. The findings do not support a direct effect of cardiac function on CBF, but demonstrates gender-related differences in cardiac output distribution. We propose fractional brain flow......) and 2.4 l min(-1) m(-2), respectively, in females. No effects of cardiac output or cardiac index on CBF or structural signs of brain ageing were observed. However, fractional brain flow defined as the ratio of total brain flow to cardiac output was inversely correlated with cardiac index (r(2) = 0.22, P...... = 0.008) and furthermore lower in males than in females (8.6% versus 12.5%, P = 0.003). Fractional brain flow was also inversely correlated with cerebral white matter lesion grade, although this effect was not significant when adjusted for age. Frequency analysis of heart rate variability showed...
8. Cardiac connexins and impulse propagation
NARCIS (Netherlands)
J.A. Jansen; T.A.B. van Veen; J.M.T. de Bakker; H.V.M. van Rijen
2010-01-01
Gap junctions form the intercellular pathway for cell-to-cell transmission of the cardiac impulse from its site of origin, the sinoatrial node, along the atria, the atrioventricular conduction system to the ventricular myocardium. The component parts of gap junctions are proteins called connexins (C
9. Postmortem cardiac imaging in fetuses and children
Energy Technology Data Exchange (ETDEWEB)
Taylor, Andrew M. [Great Ormond Street Hospital for Children NHS Foundation Trust, Cardiorespiratory Division, Level 7, Old Nurses Home, London (United Kingdom); UCL Institute of Cardiovascular Science, London (United Kingdom); Arthurs, Owen J. [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Radiology, London (United Kingdom); UCL Institute of Cardiovascular Science, London (United Kingdom); Sebire, Neil J. [UCL Institute of Cardiovascular Science, London (United Kingdom); Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Histopathology, London (United Kingdom)
2015-04-01
Fetal and pediatric cardiac autopsies have a crucial role in the counseling of parents with regard to both the cause of death of their child and the implications of such findings for future pregnancies, as well as for quality assurance of antenatal screening programs and antemortem diagnostic procedures. Postmortem imaging allows an opportunity to investigate the heart in situ prior to dissection, and both postmortem CT and postmortem MRI have shown excellent accuracy in detecting the majority of clinically significant cardiac lesions in the perinatal and pediatric population. As less-invasive autopsy becomes increasingly popular, clinical guidelines for maximal diagnostic yield in specific circumstances can be developed. (orig.)
10. Unique psoriatic lesion versus multiple lesions
Directory of Open Access Journals (Sweden)
Anca Chiriac
2014-10-01
Full Text Available Aim: To evaluate the number of lesions of psoriasis and to find risk factors for multiple lesions. Material and Methods: 1,236 patients (male 54.13%, female 45.87% with psoriasis were seen over a period of 8 years in an Outpatient Clinic. Patients filled out questionnaires containing age at onset, number of lesions and location at the beginning of the disease, gender, type and localization of psoriasis at the time of clinical examination, psoriasis family history, previous treatment, comorbidities, and social status. Results: The number of psoriasis lesions correlates with: onset age of psoriasis (F=8.902, p=0.0029; age at the moment of clinical examination (F=8.902, p=0.0029; residence in rural area (χ2=8.589, p=0.00338, 95%CI; alcohol intake (χ2=16.47, p=0.00005, 95%CI; smoking (χ2=8.408, p=0.00373, 95%CI; occupation: workers/pupils/students (χ2=14.11, p=0.0069, 95%CI. Conclusions: There is a correlation between number of psoriatic lesions and some factors. Multiple lesions were observed in older patients, smokers and drinkers, coming from rural area and social active (workers and pupils/students. No correlation was statistically proved between number of lesions and gender, comorbidities and family history of psoriasis.
11. Myocardial ischemic conditioning: Physiological aspects and clinical applications in cardiac surgery.
Science.gov (United States)
Bousselmi, Radhouane; Lebbi, Mohamed Anis; Ferjani, Mustapha
2014-04-01
Ischemia-reperfusion is a major determinant of myocardial impairment in patients undergoing cardiac surgery. The main goal of research in cardioprotection is to develop effective techniques to avoid ischemia-reperfusion lesions. Myocardial ischemic conditioning is a powerful endogenous cardioprotective phenomenon. First described in animals in 1986, myocardial ischemic conditioning consists of applying increased tolerance of the myocardium to sustained ischemia by exposing it to brief episodes of ischemia-reperfusion. Several studies have sought to demonstrate its effective cardioprotective action in humans and to understand its underlying mechanisms. Myocardial ischemic conditioning has two forms: ischemic preconditioning (IPC) when the conditioning stimulus is applied before the index ischemia and ischemic postconditioning when the conditioning stimulus is applied after it. The cardioprotective action of ischemic conditioning was reproduced by applying the ischemia-reperfusion stimulus to organs remote from the heart. This non-invasive manner of applying ischemic conditioning has led to its application in clinical settings. Clinical trials for the different forms of ischemic conditioning were mainly developed in cardiac surgery. Many studies suggest that this phenomenon can represent an interesting adjuvant to classical cardioprotection during on-pump cardiac surgery. Ischemic conditioning was also tested in interventional cardiology with interesting results. Finally, advances made in the understanding of mechanisms that underlie the cardioprotective action of ischemic conditioning have paved the way to a new form of myocardial conditioning which is pharmacological conditioning.
12. Periodontal bone lesions
International Nuclear Information System (INIS)
In the course of life the periodontum is subject to changes which may be physiological or pathological. Intraoral radiographs give insight into the hard structures of the dentomaxillar region and provides information on lesions in the bone of the periodontum in that they show radiopacities and radiolucencies caused by such lesions. In this thesis the relation is investigated between the true shape and dimensions of periodontal bone lesions and their radiographic images. A method is developed and tested of making standardized and reproducible radiographs suitable for longitudinal studies of periodontal lesions. Also the possibility is demonstrated of an objective and reproducible interpretation of radiographic characteristics of periodontal bone lesions. (Auth.)
13. Cardiac perception and cardiac control. A review.
Science.gov (United States)
Carroll, D
1977-12-01
The evidence regarding specific cardiac perception and discrimination, and its relationship to voluntary cardiac control, is critically reviewed. Studies are considered in three sections, depending on the method used to assess cardiac perception: questionnaire assessment, discrimination procedures, and heartbeat tracking. The heartbeat tracking procedure would appear to suffer least from interpretative difficulties. Recommendations are made regarding the style of analysis used to assess heartbeat perception in such tracking tasks. PMID:348240
14. Papel do óxido nítrico no desenvolvimento de lesões cardíacas na fase aguda da infecção experimental pelo Trypanosoma cruzi Role of nitric oxide in the development of cardiac lesions during the acute phase of experimental infection by Trypanosoma cruzi
Directory of Open Access Journals (Sweden)
Cláudia Renata Bibiano Borges
2009-04-01
animals (3.98 vs 1.87%; p = 0.004 and in C57BL/6 animals deficient in inducible nitric oxide synthase (3.99 vs 2.4%; p = 0.013. The cardiac parasite load in inducible nitric oxide synthase-deficient C57BL/6 animals infected with the Colombian strain was significantly greater than in those infected with the Y strain (2.78 vs. 0.17 nests/mm²; p = 0.004, and also significantly greater than in the C57BL/6 infected with both the Colombian strain (2.78 vs 1.33 nests/mm²; p = 0.006 and Y strains (2.78 vs 0.53 nests/mm²; p = 0.005. The data confirm that nitric oxide has a role in parasite load control and suggest that it has a role in tissue protection, through controlling inflammation and potentially reducing cardiac lesions during the acute phase of Chagas disease.
15. Cardiac fiber inpainting using cartan forms
DEFF Research Database (Denmark)
Puize, Emmanuel; Lombaert, Herve; Sporring, Jon;
2013-01-01
Recent progress in diffusion imaging has lead to in-vivo acquisitions of fiber orientation data in the beating heart. Current methods are however limited in resolution to a few short-axis slices. For this particular application and others where the diffusion volume is subsampled, partial or even...
16. Consanguinity and complex cardiac anomalies with situs ambiguus.
OpenAIRE
1984-01-01
A survey of British born Asian and English populations of children with congenital cardiac anomalies showed an increased incidence in the Muslim Asian population of complex lesions with visceral heterotaxia. There is a very high incidence of parental consanguinity among Muslim Asian children with complex congenital cardiac anomalies that is even higher than in the general Muslim Asian population of the area studied. The evidence suggests an important recessive genetic component in complex car...
17. Antifibrinolytics in cardiac surgery
Directory of Open Access Journals (Sweden)
Achal Dhir
2013-01-01
Full Text Available Cardiac surgery exerts a significant strain on the blood bank services and is a model example in which a multi-modal blood-conservation strategy is recommended. Significant bleeding during cardiac surgery, enough to cause re-exploration and/or blood transfusion, increases morbidity and mortality. Hyper-fibrinolysis is one of the important contributors to increased bleeding. This knowledge has led to the use of anti-fibrinolytic agents especially in procedures performed under cardiopulmonary bypass. Nothing has been more controversial in recent times than the aprotinin controversy. Since the withdrawal of aprotinin from the world market, the choice of antifibrinolytic agents has been limited to lysine analogues either tranexamic acid (TA or epsilon amino caproic acid (EACA. While proponents of aprotinin still argue against its non-availability. Health Canada has approved its use, albeit under very strict regulations. Antifibrinolytic agents are not without side effects and act like double-edged swords, the stronger the anti-fibrinolytic activity, the more serious the side effects. Aprotinin is the strongest in reducing blood loss, blood transfusion, and possibly, return to the operating room after cardiac surgery. EACA is the least effective, while TA is somewhere in between. Additionally, aprotinin has been implicated in increased mortality and maximum side effects. TA has been shown to increase seizure activity, whereas, EACA seems to have the least side effects. Apparently, these agents do not differentiate between pathological and physiological fibrinolysis and prevent all forms of fibrinolysis leading to possible thrombotic side effects. It would seem prudent to select the right agent knowing its risk-benefit profile for a given patient, under the given circumstances.
18. Cutaneous alternariosis in a cardiac transplant recipient.
Science.gov (United States)
Gilmour, T K; Rytina, E; O'Connell, P B; Sterling, J C
2001-02-01
A 55-year-old male cardiac transplant recipient presented with cutaneous nodules on the limbs caused by Alternaria alternata. Oral fluconazole 200 mg daily for 3 weeks was ineffective. Itraconazole 100 mg oral daily was ceased when hyperglycaemia developed. Individual lesions were successfully treated with either curettage and cautery or double freeze-thaw cryotherapy. Alternaria spp. are ubiquitous fungal saprophytes which may cause cutaneous infections particularly in immunocompromised patients. PMID:11233722
19. Alteration of cardiac progenitor cell potency in GRMD dogs.
Science.gov (United States)
Cassano, M; Berardi, E; Crippa, S; Toelen, J; Barthelemy, I; Micheletti, R; Chuah, M; Vandendriessche, T; Debyser, Z; Blot, S; Sampaolesi, M
2012-01-01
Among the animal models of Duchenne muscular dystrophy (DMD), the Golden Retriever muscular dystrophy (GRMD) dog is considered the best model in terms of size and pathological onset of the disease. As in human patients presenting with DMD or Becker muscular dystrophies (BMD), the GRMD is related to a spontaneous X-linked mutation of dystrophin and is characterized by myocardial lesions. In this respect, GRMD is a useful model to explore cardiac pathogenesis and for the development of therapeutic protocols. To investigate whether cardiac progenitor cells (CPCs) isolated from healthy and GRMD dogs may differentiate into myocardial cell types and to test the feasibility of cell therapy for cardiomyopathies in a preclinical model of DMD, CPCs were isolated from cardiac biopsies of healthy and GRMD dogs. Gene profile analysis revealed an active cardiac transcription network in both healthy and GRMD CPCs. However, GRMD CPCs showed impaired self-renewal and cardiac differentiation. Population doubling and telomerase analyses highlighted earlier senescence and proliferation impairment in progenitors isolated from GRMD cardiac biopsies. Immunofluorescence analysis revealed that only wt CPCs showed efficient although not terminal cardiac differentiation, consistent with the upregulation of cardiac-specific proteins and microRNAs. Thus, the pathological condition adversely influences the cardiomyogenic differentiation potential of cardiac progenitors. Using PiggyBac transposon technology we marked CPCs for nuclear dsRed expression, providing a stable nonviral gene marking method for in vivo tracing of CPCs. Xenotransplantation experiments in neonatal immunodeficient mice revealed a valuable contribution of CPCs to cardiomyogenesis with homing differences between wt and dystrophic progenitors. These results suggest that cardiac degeneration in dystrophinopathies may account for the progressive exhaustion of local cardiac progenitors and shed light on cardiac stemness in
20. Cardiac cystic echinococcosis:Report of three cases
Institute of Scientific and Technical Information of China (English)
zge Alta; Sabit Sarkaya; Hakan Sal; Onur Yerlikhan; Kaan Krali
2014-01-01
We present a retrospective analysis of three cases of cardiac hydatidosis, who underwent surgery between 2010 and 2012. Two patients had a lesion in the interventricular septum, whereas one patient had the lesion in apicoinferior wall of LV. The diagnosis was made by echocardiography, but magnetic resonance imaging was utilized to assess cyst activity and extend of disease. All patients were placed on cardiopulmonary bypass. No postoperative complication or death occurred. The patients discharged uneventfully and all of them were free from hydatid disease at two years follow-up. We concluded that cardiac hydatid cysts should be removed surgically regardless of their location or extent, even in asymptomatic patients.
1. CENTRAL AMYGDALA LESIONS AFFECT BEHAVIORAL AND AUTONOMIC BALANCE DURING STRESS IN RATS
NARCIS (Netherlands)
ROOZENDAAL, B; KOOLHAAS, JM; BOHUS, B
1991-01-01
The effects of a bilateral electrolytical lesion of the CEA on the behavioral and sympathetically induced cardiac response in the shock-probe/defensive-burying test have been analyzed in male Wistar rats. Lesions in the CEA failed to affect defensive burying and accompanying tachycardiac response as
2. Unique type of isolated cardiac valvular amyloidosis
Directory of Open Access Journals (Sweden)
Reehana Salma
2006-10-01
Full Text Available Abstract Background Amyloid deposition in heart is a common occurrence in systemic amyloidosis. But localised valvular amyloid deposits are very uncommon. It was only in 1922 that the cases of valvular amyloidosis were reported. Then in 1980, Goffin et al reported another type of valvular amyloidosis, which he called the dystrophic valvular amyloidosis. We report a case of aortic valve amyloidosis which is different from the yet described valvular amyloidosis. Case presentation A 72 years old gentleman underwent urgent aortic valve replacement. Intraoperatively, a lesion was found attached to the inferior surface of his bicuspid aortic valve. Histopathology examination of the valve revealed that the lesion contained amyloid deposits, identified as AL amyloidosis. The serum amyloid A protein (SAP scan was normal and showed no evidence of systemic amyloidosis. The ECG and echocardiogram were not consistent with cardiac amyloidosis. Conclusion Two major types of cardiac amyloidosis have been described in literature: primary-myelomatous type (occurs with systemic amyolidosis, and senile type(s. Recently, a localised cardiac dystrophic valvular amyloidosis has been described. In all previously reported cases, there was a strong association of localised valvular amyloidosis with calcific deposits. Ours is a unique case which differs from the previously reported cases of localised valvular amyloidosis. In this case, the lesion was not associated with any scar tissue. Also there was no calcific deposit found. This may well be a yet unknown type of isolated valvular amyloidosis.
3. Magnetic Resonance Imaging Evaluation of Cardiac Masses
Energy Technology Data Exchange (ETDEWEB)
2013-09-15
Cardiac tumors are extremely rare; however, when there is clinical suspicion, proper diagnostic evaluation is necessary to plan the most appropriate treatment. In this context, cardiovascular magnetic resonance imaging (CMRI) plays an important role, allowing a comprehensive characterization of such lesions. To review cases referred to a CMRI Department for investigation of cardiac and paracardiac masses. To describe the positive case series with a brief review of the literature for each type of lesion and the role of cardiovascular magnetic resonance imaging in evaluation. Between August 2008 and December 2011, all cases referred for CMRI with suspicion of tumor involving the heart were reviewed. Cases with positive histopathological diagnosis, clinical evolution or therapeutic response compatible with the clinical suspicion and imaging findings were selected. Among the 13 cases included in our study, eight (62%) had histopathological confirmation. We describe five benign tumors (myxomas, rhabdomyoma and fibromas), five malignancies (sarcoma, lymphoma, Richter syndrome involving the heart and metastatic disease) and three non-neoplastic lesions (pericardial cyst, intracardiac thrombus and infectious vegetation). CMRI plays an important role in the evaluation of cardiac masses of non-neoplastic and neoplastic origin, contributing to a more accurate diagnosis in a noninvasive manner and assisting in treatment planning, allowing safe clinical follow-up with good reproducibility.
4. Presence of satellite cells in a cardiac rhabdomyoma.
Science.gov (United States)
Trillo, A A; Holleman, I L; White, J T
1978-05-01
Cardiac rhabdomyoma is the most common tumour of the heart in infancy and childhood. The clinical presentation, diagnosis and histopathological characteristics have been extensively studied; however, reports on the ultrastructure and histogenesis of this lesion are scanty and inconclusive. The case to be discussed is that of a 10-year-old male who presented with a cardiac rhabdomyoma occupying almost the entire ventricular apex. Ultrastructurally, the rhabdomyoma cells have a central, deeply-indented nucleus surrounded by an admixture of mitochondria and sarcomeres. The remainder of the cytoplasm is occupied by pools of glycogen granules, randomly-orientated myofibrils and small mitochondria. Intercellular junctions are numerous and consist of alternating zonula occludens and macula adherens. Typical satellite cells, sharing a common basement lamina are seen apposed to the rhabdomyoma cells. It is tempting to postulate that the proliferation of the rhabdomyoma cells is accomplished by differentiation of satellite cells, a process known to occur in skeletal muscle. Ultrastructurally, the rhabdomyoma cells are indistinguishable from Purkinje cells. The presence of Purkinje-like cells in ectopic locations within the heart and their association with satellite cells is likely a form of embryological atavism. PMID:669594
5. Lesion activity assessment
DEFF Research Database (Denmark)
Ekstrand, K R; Zero, D T; Martignon, S;
2009-01-01
This chapter focusses on the probability of a caries lesion detected during a clinical examination being active (progressing) or arrested. Visual and tactile methods to assess primary coronal lesions and primary root lesions are considered. The evidence level is rated as low (R(w)), as there are...... response to cariogenic plaque as well as lesion arrest. Based on this understanding, different clinical scoring systems have been developed to assess the severity/depth and activity of lesions. A recent system has been devised by the International Caries Detection and Assessment System Committee. The...... literature suggests that there is a fair agreement between visual/tactile external scripts of caries and the severity/depth of the lesion. The reproducibility of the different systems is, in general, substantial. No single clinical predictor is able to reliably assess activity. However, a combination of...
6. Cardiac sodium channelopathies
NARCIS (Netherlands)
A.S. Amin; A. Asghari-Roodsari; H.L. Tan
2010-01-01
Cardiac sodium channel are protein complexes that are expressed in the sarcolemma of cardiomyocytes to carry a large inward depolarizing current (I-Na) during phase 0 of the cardiac action potential. The importance of I-Na for normal cardiac electrical activity is reflected by the high incidence of
7. Ghost cell lesions
Directory of Open Access Journals (Sweden)
E Rajesh
2015-01-01
Full Text Available Ghost cells have been a controversy for a long time. Ghost cell is a swollen/enlarged epithelial cell with eosnophilic cytoplasm, but without a nucleus. In routine H and E staining these cells give a shadowy appearance. Hence these cells are also called as shadow cells or translucent cells. The appearance of these cells varies from lesion to lesion involving odontogenic and nonodontogenic lesions. This article review about the origin, nature and significance of ghost cells in different neoplasms.
8. Cardiac metastasis from colorectal cancer: A case report
Institute of Scientific and Technical Information of China (English)
Pyong Wha Choi; Chul Nam Kim; Sun Hee Chang; Woo Ik Chang; Chang Young Kim; Hyun Min Choi
2009-01-01
The heart is an unusual site of metastasis from any malignancy. We report a case of cardiac metastasis from colorectal cancer. A 70-year-old woman was referred with a presumptive diagnosis of sigmoid colon cancer with cardiac myxoma. Two-dimensional echocardiography showed a 4 cm × 4.5 cm mobile mass on the lateral right atrial wall, and computed tomography revealed a low attenuated lobulating mass in the right atrium. The patient underwent anterior resection for sigmoid colon cancer (T4N2). Thereafter, she experienced progressive shortness of breath. Therefore, a cardiac operation was performed 2 wk after the colorectal operation.Histological examination revealed adenocarcinoma,which was identical to the primary lesion. Although twodimensional echocardiography has become the diagnostic test of choice for detecting cardiac tumors, in patients with colorectal cancer showing a cardiac mass, further diagnostic evaluation such as a magnetic resonance imaging might be necessary.
9. Incretin attenuates diabetes-induced damage in rat cardiac tissue.
Science.gov (United States)
AbdElmonem Elbassuoni, Eman
2014-09-01
Glucagon-like peptide-1 (GLP-1), as a member of the incretin family, has a role in glucose homeostasis, its receptors distributed throughout the body, including the heart. The aim was to investigate cardiac lesions following diabetes induction, and the potential effect of GLP-1 on this type of lesions and the molecular mechanism driving this activity. Adult male rats were classified into: normal, diabetic, 4-week high-dose exenatide-treated diabetic rats, 4-week low-dose exenatide-treated diabetic rats, and 1-week exenatide-treated diabetic rats. The following parameters were measured: in blood: glucose, insulin, lactate dehydrogenase (LDH), total creatine kinase (CK), creatine kinase MB isoenzyme (CK-MB), and CK-MB relative index; in cardiac tissue: lipid peroxide (LPO) and some antioxidant enzymes. The untreated diabetic group displayed significant increases in blood level of glucose, LDH, and CK-MB, and cardiac tissue LPO, and a significant decrease in cardiac tissue antioxidant enzymes. GLP-1 supplementation in diabetic rats definitely decreased the hyperglycemia and abolished the detrimental effects of diabetes on the cardiac tissue. The effect of GLP-1 on blood glucose and on the heart also appeared after a short supplementation period (1 week). It can be concluded that GLP-1 has beneficial effects on diabetes-induced oxidative cardiac tissue damage, most probably via its antioxidant effect directly acting on cardiac tissue and independent of its hypoglycemic effect. PMID:25011640
10. Hyperkalaemia, cardiac arrhythmias, and cerebral lesions in high risk neonates.
OpenAIRE
Shortland, D; Trounce, J Q; Levene, M I
1987-01-01
The case notes of 20 infants with hyperkalaemia (defined as two successive serum potassium measurements of greater than 7.5 mmol/l) were reviewed. The incidence of hyperkalaemia was also looked at in an unselected population of 200 low birthweight infants. The mean gestational age of the 20 affected infants was 29 weeks and the mean birth weight 1235 g. The incidence of hyperkalemia in the cohort of 200 infants weighing less than 1500 g at birth was 3.5%. Hyperkalaemia was associated with a h...
11. Microbiological aspects of endoperiodontal lesion
Directory of Open Access Journals (Sweden)
Cristiane Tokunaga
2013-06-01
Full Text Available Introduction: The endoperiodontal lesion occurs when a tooth undergoing endodontic disease is united to a periodontal lesion with apical progression. Many times, the differential diagnosis between the endodontic and periodontal disease can be of difficult execution and the correct diagnosis and planing of the treatment is of main importance for a good prognosis Objective: To identify the main microorganisms within the lesion of endodontic and periodontal origin and correlate them with the endoperiodontal lesion. Literature review: The search strategy comprised the electronic studies of databases such as PubMed and Cochrane on the microbiology of the endodontic and periodontal systems through employing the following keywords: microbiology, endodontics, periodontal pocket. Results: There were similarities in the endodontic and periodontal microflora. However, the number of microorganisms within the cross infection is limited, including Bacteroides, Eubacteria, Fusobacteria, spirochaetes, Wolinella. The bacterias forming the red complex are closely related to the severity of the periodontal disease and can also participate in the pathogenesis of the periradicular abscesses. Conclusion: There are many communication routes between the periodontium and pulpal tissue, therefore the contamination from um tissue to another can occur, existing a microbiological inter-relationship between these tissues.
12. Chronic radiodermatitis following cardiac catheterisation: a report of two cases and a brief review of the literature.
Science.gov (United States)
Dehen, L; Vilmer, C; Humilière, C; Corcos, T; Pentousis, D; Ollivaud, L; Chatelain, D; Dubertret, L
1999-03-01
Cardiac angiography produces one of the highest radiation exposures of any commonly used diagnostic x ray procedure. Recently, serious radiation induced skin injuries have been reported after repeated therapeutic interventional procedures using prolonged fluoroscopic imaging. Two male patients, aged 62 and 71 years, in whom chronic radiodermatitis developed one to two years after two consecutive cardiac catheterisation procedures are reported. Both patients had undergone lengthy procedures using prolonged fluoroscopic guidance in a limited number of projections. The resulting skin lesions were preceded, in one case, by an acute erythema and took the form of a delayed pigmented telangiectatic, indurated, or ulcerated plaque in the upper back or below the axilla whose site corresponded to the location of the x ray tube during cardiac catheterisation. Cutaneous side effects of radiation exposure result from direct damage to the irradiated tissue and have known thresholds. The diagnosis of radiation induced skin injury relies essentially on clinical and histopathological findings, location of skin lesions, and careful medical history. Interventional cardiologists should be aware of this complication, because chronic radiodermatitis may result in painful and resistant ulceration and eventually in squamous cell carcinoma.
13. Cardiac tumours in children
Directory of Open Access Journals (Sweden)
Parsons Jonathan M
2007-03-01
Full Text Available Abstract Cardiac tumours are benign or malignant neoplasms arising primarily in the inner lining, muscle layer, or the surrounding pericardium of the heart. They can be primary or metastatic. Primary cardiac tumours are rare in paediatric practice with a prevalence of 0.0017 to 0.28 in autopsy series. In contrast, the incidence of cardiac tumours during foetal life has been reported to be approximately 0.14%. The vast majority of primary cardiac tumours in children are benign, whilst approximately 10% are malignant. Secondary malignant tumours are 10–20 times more prevalent than primary malignant tumours. Rhabdomyoma is the most common cardiac tumour during foetal life and childhood. It accounts for more than 60% of all primary cardiac tumours. The frequency and type of cardiac tumours in adults differ from those in children with 75% being benign and 25% being malignant. Myxomas are the most common primary tumours in adults constituting 40% of benign tumours. Sarcomas make up 75% of malignant cardiac masses. Echocardiography, Computing Tomography (CT and Magnetic Resonance Imaging (MRI of the heart are the main non-invasive diagnostic tools. Cardiac catheterisation is seldom necessary. Tumour biopsy with histological assessment remains the gold standard for confirmation of the diagnosis. Surgical resection of primary cardiac tumours should be considered to relieve symptoms and mechanical obstruction to blood flow. The outcome of surgical resection in symptomatic, non-myxomatous benign cardiac tumours is favourable. Patients with primary cardiac malignancies may benefit from palliative surgery but this approach should not be recommended for patients with metastatic cardiac tumours. Surgery, chemotherapy and radiotherapy may prolong survival. The prognosis for malignant primary cardiac tumours is generally extremely poor.
14. Postmortem MR quantification of the heart for characterization and differentiation of ischaemic myocardial lesions
Energy Technology Data Exchange (ETDEWEB)
Zech, Wolf-Dieter; Schwendener, Nicole; Jackowski, Christian [University of Bern, Institute of Forensic Medicine, Bern (Switzerland); Persson, Anders; Warntjes, Marcel J. [University of Linkoeping, Center for Medical Image Science and Visualization (CMIV), Linkoeping (Sweden)
2015-07-15
Recently, an MRI quantification sequence has been developed which can be used to acquire T1- and T2-relaxation times as well as proton density (PD) values. Those three quantitative values can be used to describe soft tissue in an objective manner. The purpose of this study was to investigate the applicability of quantitative cardiac MRI for characterization and differentiation of ischaemic myocardial lesions of different age. Fifty post-mortem short axis cardiac 3 T MR examinations have been quantified using a quantification sequence. Myocardial lesions were identified according to histology and appearance in MRI images. Ischaemic lesions were assessed for mean T1-, T2- and proton density values. Quantitative values were plotted in a 3D-coordinate system to investigate the clustering of ischaemic myocardial lesions. A total of 16 myocardial lesions detected in MRI images were histologically characterized as acute lesions (n = 8) with perifocal oedema (n = 8), subacute lesions (n = 6) and chronic lesions (n = 2). In a 3D plot comprising the combined quantitative values of T1, T2 and PD, the clusters of all investigated lesions could be well differentiated from each other. Post-mortem quantitative cardiac MRI is feasible for characterization and discrimination of different age stages of myocardial infarction. (orig.)
15. Cardiac Assessment.
Science.gov (United States)
Fritz, Deborah; McKenzie, Patricia
2015-10-01
Heart disease remains the number one cause of mortality in both men and women in the United States and patients with heart failure are at high risk for hospitalization. Thirty-day readmission rates have become a benchmark for hospitals and home healthcare agency reimbursement. Physical exam and history taking are essential to evaluate patients with suspected or known heart disease, and to detect early symptoms of worsening heart failure. Home care clinicians have the opportunity to assess the patient in the home environment, identify significant changes in the patient's status, and form a plan of care for effective intervention to prevent the need for emergency department care or rehospitalization. In this second article of a four-part series, the subjective and objective assessment of the cardiovascular system exam is reviewed. PMID:26418104
16. Stimulating endogenous cardiac regeneration
Directory of Open Access Journals (Sweden)
Amanda eFinan
2015-09-01
Full Text Available The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration,a combination of these approaches couldameliorate the overall repair process to incorporate the participation ofmultiple cell players.
17. Reversible focal splenial lesions
Energy Technology Data Exchange (ETDEWEB)
Gallucci, Massimo; Limbucci, Nicola [University of L' Aquila, Department of Radiology, S. Salvatore Hospital, L' Aquila (Italy); Paonessa, Amalia [Loreto Nuovo Hospital, Department of Neuroradiology, Napoli (Italy); Caranci, Ferdinando [Federico II University, Department of Neurological Sciences, Napoli (Italy)
2007-07-15
Reversible focal lesions in the splenium of the corpus callosum (SCC) have recently been reported.They are circumscribed and located in the median aspect of the SCC. On MRI, they are hyperintense on T2-W and iso-hypointense on T1-W sequences, with no contrast enhancement. On DWI, SCC lesions are hyperintense with low ADC values, reflecting restricted diffusion due to cytotoxic edema. The common element is the disappearance of imaging abnormalities with time, including normalization of DWI. Clinical improvement is often reported. The most established and frequent causes of reversible focal lesions of the SCC are viral encephalitis, antiepileptic drug toxicity/withdrawal and hypoglycemic encephalopathy. Many other causes have been reported, including traumatic axonal injury. The similar clinical and imaging features suggest a common mechanism induced by different pathological events leading to the same results. Edema and diffusion restriction in focal reversible lesions of the SCC have been attributed to excitotoxic mechanisms that can result from different mechanisms; no unifying relationship has been found to explain all the pathologies associated with SCC lesions. In our opinion, the similar imaging, clinical and prognostic aspects of these lesions depend on a high vulnerability of the SCC to excitotoxic edema and are less dependent on the underlying pathology. In this review, the relevant literature concerning reversible focal lesions in the SCC is analyzed and hypotheses about their pathogenesis are proposed. (orig.)
18. Intraosseous osteolytic lesions
Energy Technology Data Exchange (ETDEWEB)
1981-10-01
Any pathological damage occurring in a bone will produce either an osteolytic or osteosclerotic lesion which can be seen in the macroscopic specimen as well as in the roentgenogram. Various bone lesions may lead to local destructions of the bone. An osteoma or osteoplastic osteosarcoma produces an osteosclerotic lesion showing a dense mass in the roentgenogram; a chondroblastoma or an osteoclastoma, on the other hand, induces an osteolytic focal lesion. This paper presents examples of different osteolytic lesions of the humerus. An osteolytic lesion seen in the roentgenogram may be either produced by an underlying non-ossifying fibroma of the bone, by fibrous dysplasia, osteomyelitis or Ewing's sarcoma. Differential diagnostic considerations based on the radiological picture include eosinophilic bone granuloma, juvenile or aneurysmal bone cyst, multiple myeloma or bone metastases. Serious differential diagnostic problems may be involved in case of osteolytic lesions occurring in the humerus. Cases of this type involving complications have been reported and include the presence of an teleangiectatic osteosarcoma as well as that of a hemangiosarcoma of the bone.
19. Oral Lesions in Neonates
Science.gov (United States)
Rao, Roopa S; Majumdar, Barnali; Jafer, Mohammed; Maralingannavar, Mahesh; Sukumaran, Anil
2016-01-01
ABSTRACT Oral lesions in neonates represent a wide range of diseases often creating apprehension and anxiety among parents. Early examination and prompt diagnosis can aid in prudent management and serve as baseline against the future course of the disease. The present review aims to enlist and describe the diagnostic features of commonly encountered oral lesions in neonates. How to cite this article: Patil S, Rao RS, Majumdar B, Jafer M, Maralingannavar M, Sukumaran A. Oral Lesions in Neonates. Int J Clin Pediatr Dent 2016;9(2):131-138. PMID:27365934
20. Intraocular lymphoma after cardiac transplantation: Magnetic resonance imaging findings
Energy Technology Data Exchange (ETDEWEB)
Kim, Yi Kyung; Kim, Hyung Jin; Woo, Kyung In; Kim, Yoon Duck [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)
2013-01-15
We report a case of intraocular lymphoma in a 65-year-old man, 15 months after cardiac transplantation. On Magnetic Resonance (MR) images, the iris and the anterior chamber of the right eye were found to be involved with an enhancing soft-tissue lesion. To our knowledge, this is the first case of post-transplantation intraocular lymphoma evaluated with MR imaging.
1. Cardiac ryanodine receptor gene (hRyR2) mutation underlying catecholaminergic polymorphic ventricular tachycardia in a Chinese adolescent presenting with sudden cardiac arrest and cardiac syncope
Institute of Scientific and Technical Information of China (English)
Ngai-Shing Mok; Ching-Wan Lam; Nai-Chung Fong; Yim-Wo Hui; Yuen-Choi Choi; Kwok-Yin Chan
2006-01-01
@@ Sudden cardiac death (SCD) in children and adolescents is uncommon and yet it is devastating for both victim's family and the society.Recently, it was increasingly recognized that SCD in young patients with structurally normal heart may be caused by inheritable primary electrical diseases due to the malfunction of cardiac ion channels, a disease entity known as the ion channelopathies.Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a specific form of ion channelopathy which can cause cardiac syncope or SCD in young patients by producing catecholamine-induced bi-directional ventricular tachycardia (BiVT), polymorphic VT and ventricular fibrillation (VF) during physical exertion or emotion.1-7 We reported here an index case of CPVT caused by cardiac ryanodine receptor gene (hRyR2)mutation which presented as cardiac syncope and sudden cardiac arrest in a Chinese adolescent female.
2. Managing Carious Lesions
DEFF Research Database (Denmark)
Schwendicke, F; Frencken, J E; Bjørndal, L;
2016-01-01
The International Caries Consensus Collaboration undertook a consensus process and here presents clinical recommendations for carious tissue removal and managing cavitated carious lesions, including restoration, based on texture of demineralized dentine. Dentists should manage the disease dental ...
3. Diffuse cavitary lung lesions
Energy Technology Data Exchange (ETDEWEB)
Grunzke, Mindy; Garrington, Timothy [University of Colorado Denver, Department of Pediatrics, Aurora, CO (United States); The Children' s Hospital, Rick Wilson Center for Cancer and Blood Disorders, Aurora, CO (United States); Hayes, Kari [The Children' s Hospital, Pediatric Radiology, Aurora, CO (United States); Bourland, Wendy [Children' s Hospital at St. Francis, Warren Clinic, Inc., Tulsa, OK (United States)
2010-02-15
An 11-year-old girl presented with a 2-month history of progressively worsening cough, daily fevers, and weight loss. A chest radiograph revealed multiple cystic cavitary lung lesions. An extensive infectious work-up was negative. Chest CT verified multiple cavitary lung lesions bilaterally, and [F-18]2-fluoro-2-deoxy-D-glucose ({sup 18}F-FDG) positron emission tomography with CT (PET/CT) showed increased uptake in the lung lesions as well as regional lymph nodes. Subsequent biopsy of an involved lymph node confirmed classical Hodgkin lymphoma, nodular sclerosis type. This case represents an unusual presentation for a child with Hodgkin lymphoma and demonstrates a role for {sup 18}F-FDG PET/CT in evaluating a child with cavitary lung lesions. (orig.)
4. Marketing cardiac CT programs.
Science.gov (United States)
Scott, Jason
2010-01-01
There are two components of cardiac CT discussed in this article: coronary artery calcium scoring (CACS) and coronary computed tomography angiography (CCTA).The distinctive advantages of each CT examination are outlined. In order to ensure a successful cardiac CT program, it is imperative that imaging facilities market their cardiac CT practices effectively in order to gain a competitive advantage in this valuable market share. If patients receive quality care by competent individuals, they are more likely to recommend the facility's cardiac CT program. Satisfied patients will also be more willing to come back for any further testing.
5. Andersson Lesion in Ankylosing Spondylitis
Directory of Open Access Journals (Sweden)
Manimegalai N, KrishnanKutty K, Panchapakesa Rajendran C, Rukmangatharajan S, Rajeswari S
2004-04-01
Full Text Available Andersson lesions are destructive foci that appear at the discovertebral junction in ankylosingspondylitis. We report three cases of ankylosing spondylitis with such lesions. These lesions simulatean infection and in our country, mimic spinal tuberculosis.
6. Clinical correlations of brain lesion distribution in multiple sclerosis
DEFF Research Database (Denmark)
Vellinga, M M; Geurts, J J G; Rostrup, E;
2009-01-01
status scale (EDSS) and MS functional composite (MSFC) subdomain scores and demographic characteristics of 325 MS patients. To identify statistically significant locations, a cluster-forming threshold of 3.1 was used. RESULTS: In clusters in the periventricular region, lesion probability correlated...... significantly (P correlate with lesion probability in any location, and did...... not influence correlations with disability when included in its analyses. CONCLUSION: Periventricular lesions were related to disability. LL influenced relations between disability and lesion probability throughout the brain, suggesting interplay between lesional burden and its location in determining...
7. Mathematical cardiac electrophysiology
CERN Document Server
Colli Franzone, Piero; Scacchi, Simone
2014-01-01
This book covers the main mathematical and numerical models in computational electrocardiology, ranging from microscopic membrane models of cardiac ionic channels to macroscopic bidomain, monodomain, eikonal models and cardiac source representations. These advanced multiscale and nonlinear models describe the cardiac bioelectrical activity from the cell level to the body surface and are employed in both the direct and inverse problems of electrocardiology. The book also covers advanced numerical techniques needed to efficiently carry out large-scale cardiac simulations, including time and space discretizations, decoupling and operator splitting techniques, parallel finite element solvers. These techniques are employed in 3D cardiac simulations illustrating the excitation mechanisms, the anisotropic effects on excitation and repolarization wavefronts, the morphology of electrograms in normal and pathological tissue and some reentry phenomena. The overall aim of the book is to present rigorously the mathematica...
8. Biomaterials for cardiac regeneration
CERN Document Server
Ruel, Marc
2015-01-01
This book offers readers a comprehensive biomaterials-based approach to achieving clinically successful, functionally integrated vasculogenesis and myogenesis in the heart. Coverage is multidisciplinary, including the role of extracellular matrices in cardiac development, whole-heart tissue engineering, imaging the mechanisms and effects of biomaterial-based cardiac regeneration, and autologous bioengineered heart valves. Bringing current knowledge together into a single volume, this book provides a compendium to students and new researchers in the field and constitutes a platform to allow for future developments and collaborative approaches in biomaterials-based regenerative medicine, even beyond cardiac applications. This book also: Provides a valuable overview of the engineering of biomaterials for cardiac regeneration, including coverage of combined biomaterials and stem cells, as well as extracellular matrices Presents readers with multidisciplinary coverage of biomaterials for cardiac repair, including ...
9. Meniscal Ramp Lesions
Science.gov (United States)
Chahla, Jorge; Dean, Chase S.; Moatshe, Gilbert; Mitchell, Justin J.; Cram, Tyler R.; Yacuzzi, Carlos; LaPrade, Robert F.
2016-01-01
Meniscal ramp lesions are more frequently associated with anterior cruciate ligament (ACL) injuries than previously recognized. Some authors suggest that this entity results from disruption of the meniscotibial ligaments of the posterior horn of the medial meniscus, whereas others support the idea that it is created by a tear of the peripheral attachment of the posterior horn of the medial meniscus. Magnetic resonance imaging (MRI) scans have been reported to have a low sensitivity, and consequently, ramp lesions often go undiagnosed. Therefore, to rule out a ramp lesion, an arthroscopic evaluation with probing of the posterior horn of the medial meniscus should be performed. Several treatment options have been reported, including nonsurgical management, inside-out meniscal repair, or all-inside meniscal repair. In cases of isolated ramp lesions, a standard meniscal repair rehabilitation protocol should be followed. However, when a concomitant ACL reconstruction (ACLR) is performed, the rehabilitation should follow the designated ACLR postoperative protocol. The purpose of this article was to review the current literature regarding meniscal ramp lesions and summarize the pertinent anatomy, biomechanics, diagnostic strategies, recommended treatment options, and postoperative protocol. PMID:27504467
10. [EVOLUTION OF MINIMALLY INVASIVE CARDIAC SURGERY].
Science.gov (United States)
Fujita, Tomoyuki; Kobayashi, Junjiro
2016-03-01
Minimally invasive surgery is an attractive choice for patients undergoing major cardiac surgery. We review the history of minimally invasive valve surgery in this article. Due to many innovations in surgical tools, cardiopulmonary bypass systems, visualization systems, and robotic systems as well as surgical techniques, minimally invasive cardiac surgery has become standard care for valve lesion repair. In particular, aortic cross-clamp techniques and methods for cardioplegia using the Chitwood clamp and root cannula or endoballoon catheter in combination with femoro-femoral bypass systems have made such procedures safer and more practical. On the other hand, robotically assisted surgery has not become standard due to the cost and slow learning curve. However, along with the development of robotics, this less-invasive technique may provide another choice for patients in the near future. PMID:27295770
11. Telocytes in cardiac regeneration and repair.
Science.gov (United States)
Bei, Yihua; Zhou, Qiulian; Sun, Qi; Xiao, Junjie
2016-07-01
Telocytes (TCs) are a novel type of stromal cells reported by Popescu's group in 2010. The unique feature that distinguishes TCs from other "classical" stromal cells is their extremely long and thin telopodes (Tps). As evidenced by electron microscopy, TCs are widely distributed in almost all tissues and organs. TCs contribute to form a three-dimensional interstitial network and play as active regulators in intercellular communication via homocellular/heterocellular junctions or shed vesicles. Interestingly, increasing evidence suggests the potential role of TCs in regenerative medicine. Although the heart retains some limited endogenous regenerative capacity, cardiac regenerative and repair response is however insufficient to make up the loss of cardiomyocytes upon injury. Developing novel strategies to increase cardiomyocyte renewal and repair is of great importance for the treatment of cardiac diseases. In this review, we focus on the role of TCs in cardiac regeneration and repair. We particularly describe the intercellular communication between TCs and cardiomyocytes, stem/progenitor cells, endothelial cells, and fibroblasts. Also, we discuss the current knowledge about TCs in cardiac repair after myocardial injury, as well as their potential roles in cardiac development and aging. TC-based therapy or TC-derived exosome delivery might be used as novel therapeutic strategies to promote cardiac regeneration and repair. PMID:26826525
12. Lesiones deportivas Sports injuries
OpenAIRE
Isabel Cristina Gallego Ching; Santiago Patiño Giraldo; Elkín Arango V.; Mónica Paola Clavijo Rodríguez; Jorge Alberto Osorio Ciro
2007-01-01
El estrés generado por la práctica deportiva ha originado una mayor probabilidad de que los atletas presenten lesiones agudas y crónicas. En el ámbito mundial existen diferentes investigaciones acerca de la incidencia de lesiones deportivas. La comparación de sus resultados es difícil por las diferencias en las características de la población y en la forma de reportar los datos, que varía ampliamente entre los estudios (proporciones o tasas de incidencia o tasas por cada 100 ó 1.000 participa...
13. The hydantoin lesions formed from oxidation of 7,8-dihydro-8-oxoguanine are potnt sources of replication errors in vivo; Henderson, P.T.; Delaney, J.C.; Muller, J. G.; Neeley, W.L.; Tannenbaum, S.R.; Burrows, C.J.; Essigmann, J.M. Biochemistry (accelerate
Energy Technology Data Exchange (ETDEWEB)
Henderson, P; Delaney, J; Muller, J; Neeley, W; Tannenbaum, S; Burrows, C; Essigmann, J
2003-10-27
Single-stranded DNA genomes have been constructed that site-specifically contain the 8-oxo-7,8-dihydro-2'-deoxyguanine (8-oxoG) oxidation products guanidinohyndantoin (Gh), and the two stable stereoisomers of spiroiminodihydantoin (Sp1 and Sp2). The circular viral genomes were transfected into wild-type AB1157 Escherichia coli and the efficiency of lesion bypass by DNA polymerase(s) was assessed. Viral progeny were analyzed for mutation frequency and type using the recently developed restriction endonuclease and post-labeling (REAP) assay. Gh was bypassed nearly as efficiently as the parent 8-oxoG, but was highly mutagenic, causing almost exclusive G{yields}C transversions. The stereoisomers Sp1 and Sp2 were, in comparison, much stronger blocks to DNA polymerase extension, and caused a mixture of G{yields}T and G{yields}C transversions. The ratio of G{yields}T to G{yields}C mutations for each Sp lesion was dependent on the stereochemical configuration of the base. All observed mutation frequencies were at least an order of magnitude higher than those caused by 8-oxoG. Were these lesions to be formed in vivo, our data show that they are absolutely miscoding, and may be refractory to repair after translesion synthesis.
14. [Cardiac evaluation before non-cardiac surgery].
Science.gov (United States)
Menzenbach, Jan; Boehm, Olaf
2016-07-01
Before non-cardiac surgery, evaluation of cardiac function is no frequent part of surgical treatment. European societies of anesthesiology and cardiology published consensus-guidelines in 2014 to present a reasonable approach for preoperative evaluation. This paper intends to differentiate the composite of perioperative risk and to display the guidelines methodical approach to handle it. Features to identify patients at risk from an ageing population with comorbidities, are the classification of surgical risk, functional capacity and risk indices. Application of diagnostic means, should be used adjusted to this risk estimation. Cardiac biomarkers are useful to discover risk of complications or mortality, that cannot be assessed by clinical signs. After preoperative optimization and perioperative cardiac protection, the observation of the postoperative period remains, to prohibit complications or even death. In consideration of limited resources of intensive care department, postoperative ward rounds beyond intensive care units are considered to be an appropriate instrument to avoid or recognize complications early to reduce postoperative mortality. PMID:27479258
15. Relations among traumatic subdural lesions.
OpenAIRE
Lee, K. S.; Doh, J. W.; Bae, H. G.; Yun, I. G.
1996-01-01
Acute subdural hematoma (ASDH), chronic subdural hematoma (CSDH) and subdural hygroma (SDG) occur in the subdural space, usually after trauma. We tried to find a certain relationship among these three traumatic subdural lesions in 436 consecutive patients. We included all subdural lesions regardless of whether they were main or not. We evaluated the distribution, age incidence and interval from injury to diagnosis of these lesions, and the frequency of new subdural lesions in each lesion. ASD...
16. Genital lesions following bestiality
Directory of Open Access Journals (Sweden)
Mittal A
2000-01-01
Full Text Available A 48-year-old man presented with painful genital lesions with history of bestiality and abnor-mal sexual behaviour. Examination revealed multiple irregular tender ulcers and erosions, with phimosis and left sided tender inguinal adenopathy. VDRL, TPHA, HIV-ELISA were negative. He was treated with ciprofloxacin 500mg b.d. along with saline compresses with complete resolution.
17. White matter lesion progression
DEFF Research Database (Denmark)
Hofer, Edith; Cavalieri, Margherita; Bis, Joshua C;
2016-01-01
BACKGROUND AND PURPOSE: White matter lesion (WML) progression on magnetic resonance imaging is related to cognitive decline and stroke, but its determinants besides baseline WML burden are largely unknown. Here, we estimated heritability of WML progression, and sought common genetic variants asso...
18. Cardiac metabolism and arrhythmias
OpenAIRE
Barth, Andreas S.; Tomaselli, Gordon F.
2009-01-01
Sudden cardiac death remains a leading cause of mortality in the Western world, accounting for up to 20% of all deaths in the U.S.1, 2 The major causes of sudden cardiac death in adults age 35 and older are coronary artery disease (70–80%) and dilated cardiomyopathy (10–15%).3 At the molecular level, a wide variety of mechanisms contribute to arrhythmias that cause sudden cardiac death, ranging from genetic predisposition (rare mutations and common polymorphisms in ion channels and structural...
19. Comprehensive cardiac rehabilitation
DEFF Research Database (Denmark)
Kruse, Marie; Hochstrasser, Stefan; Zwisler, Ann-Dorthe O;
2006-01-01
OBJECTIVES: The costs of comprehensive cardiac rehabilitation are established and compared to the corresponding costs of usual care. The effect on health-related quality of life is analyzed. METHODS: An unprecedented and very detailed cost assessment was carried out, as no guidelines existed...... and may be as high as euro 1.877. CONCLUSIONS: Comprehensive cardiac rehabilitation is more costly than usual care, and the higher costs are not outweighed by a quality of life gain. Comprehensive cardiac rehabilitation is, therefore, not cost-effective....
20. Sudden Death and Myocardial Lesions after Damage to Catecholamine Neurons of the Nucleus Tractus Solitarii in Rat
OpenAIRE
Talman, William T.; Dragon, Deidre Nitschke; Jones, Susan Y.; Moore, Steven A.; Lin, Li-Hsien
2012-01-01
Lesions that remove neurons expressing neurokinin-1 (NK1) receptors from the nucleus tractus solitarii (NTS) without removing catecholaminergic neurons lead to loss of baroreflexes, labile arterial pressure, myocardial lesions and sudden death. Because destruction of NTS catecholaminergic neurons expressing tyrosine hydroxylase (TH) may also cause lability of arterial pressure and loss of baroreflexes, we sought to test the hypothesis that cardiac lesions associated with lability are not depe...
1. Morel-Lavallee lesion
Institute of Scientific and Technical Information of China (English)
Li Hui; Zhang Fangjie; Lei Guanghua
2014-01-01
Objective To review current knowledge of the Morel-Lavallee lesion (MLL) to help clinicians become familiar with this entity.Familiarization may decrease missed diagnoses and misdiagnoses.It could also help steer the clinician to the proper treatment choice.Data sources A search was performed via PubMed and EMBASE from 1966 to July 2013 using the following keywords:Morel-Lavallee lesion,closed degloving injury,concealed degloving injury,Morel-Lavallee effusion,Morel-Lavallee hematoma,posttraumatic pseudocyst,posttraumatic soft tissue cyst.Study selection Chinese and English language literatures relevant to the subject were collected.Their references were also reviewed.Results Morel-Lavallee lesion is a relatively rare condition involving a closed degloving injury.It is characterized by a filled cystic cavity created by separation of the subcutaneous tissue from the underlying fascia.Apart from the classic location over the region of the greater trochanter,MLLs have been described in other parts of the body.The natural history of MLL has not yet been established.The lesion may decrease in volume,remain stable,enlarge progressively or show a recurrent pattern.Diagnosis of MLL was often missed or delayed.Ultrasonography,computed tomography,and magnetic resonance imaging have great value in the diagnosis of MLL.Treatment of MLL has included compression,local aspiration,open debridement,and sclerodesis.No standard treatment has been established.Conclusions A diagnosis of MLL should be suspected when a soft,fluctuant area of skin or chronic recurrent fluid collection is found in a region exposed to a previous shear injury.Clinicians and radiologists should be aware of both the acute and chronic appearances to make the correct diagnosis.Treatment decisions should base on association with fractures,the condition of the lesion,symptom and desire of the patient.
2. Cardiac Risk Assessment
Science.gov (United States)
... to assess cardiac risk include: High-sensitivity C-reactive protein (hs-CRP) : Studies have shown that measuring ... LDL-C but does not respond to typical strategies to lower LDL-C such as diet, exercise, ...
3. Sudden Cardiac Arrest
Science.gov (United States)
... Heart Risk Factors & Prevention Heart Diseases & Disorders Atrial Fibrillation (AFib) Sudden Cardiac Arrest (SCA) SCA: Who's At Risk? Prevention of SCA What Causes SCA? SCA Awareness Atrial Flutter Heart Block Heart Failure Sick Sinus Syndrome Substances & Heart Rhythm Disorders Symptoms & ...
4. Socially differentiated cardiac rehabilitation
DEFF Research Database (Denmark)
Meillier, Lucette Kirsten; Nielsen, Kirsten Melgaard; Larsen, Finn Breinholt;
2012-01-01
to a standard rehabilitation programme (SRP). If patients were identified as socially vulnerable, they were offered an extended version of the rehabilitation programme (ERP). Excluded patients were offered home visits by a cardiac nurse. Concordance principles were used in the individualised programme elements......%. Patients were equally distributed to the SRP and the ERP. No inequality was found in attendance and adherence among referred patients. Conclusions: It seems possible to overcome unequal referral, attendance, and adherence in cardiac rehabilitation by organisation of systematic screening and social......Aim: The comprehensive cardiac rehabilitation (CR) programme after myocardial infarction (MI) improves quality of life and results in reduced cardiac mortality and recurrence of MI. Hospitals worldwide face problems with low participation rates in rehabilitation programmes. Inequality...
5. Cardiac arrest - cardiopulmonary resuscitation
Institute of Scientific and Technical Information of China (English)
Basri Lenjani; Besnik Elshani; Nehat Baftiu; Kelmend Pallaska; Kadir Hyseni; Njazi Gashi; Nexhbedin Karemani; Ilaz Bunjaku; Taxhidin Zaimi; Arianit Jakupi
2014-01-01
Objective:To investigate application of cardiopulmonary resuscitation(CPR) measures within the golden minutes inEurope.Methods:The material was taken from theUniversityClinical Center ofKosovo -EmergencyCentre inPristina, during the two(2) year period(2010-2011).The collected date belong to the patients with cardiac arrest have been recorded in the patients' log book protocol at the emergency clinic.Results:During the2010 to2011 in the emergency center of theCUCK inPristina have been treated a total of269 patients with cardiac arrest, of whom159 or59.1% have been treated in2010, and110 patients or40.9% in2011.Of the269 patients treated in the emergency centre,93 or34.6% have exited lethally in the emergency centre, and176 or 65.4% have been transferred to other clinics.In the total number of patients with cardiac arrest, males have dominated with186 cases, or69.1%.The average age of patients included in the survey was56.7 year oldSD±16.0 years.Of the269 patients with cardiac arrest, defibrillation has been applied for93 or34.6% of patients.In the outpatient settings defibrillation has been applied for3 or3.2% of patients.Patients were defibrillated with application of one to four shocks. Of27 cases with who have survived cardiac arrest, none of them have suffered cardiac arrest at home,3 or11.1% of them have suffered cardiac arrest on the street, and24 or88.9% of them have suffered cardiac arrest in the hospital.5 out of27 patients survived have ended with neurological impairment.Cardiac arrest cases were present during all days of the week, but frequently most reported cases have been onMonday with32.0% of cases, and onFriday with24.5% of cases. Conclusions:All survivors from cardiac arrest have received appropriate medical assistance within10 min from attack, which implies that if cardiac arrest occurs near an institution health care(with an opportunity to provide the emergent health care) the rate of survival is higher.
6. Awareness in cardiac anesthesia.
LENUS (Irish Health Repository)
Serfontein, Leon
2010-02-01
Cardiac surgery represents a sub-group of patients at significantly increased risk of intraoperative awareness. Relatively few recent publications have targeted the topic of awareness in this group. The aim of this review is to identify areas of awareness research that may equally be extrapolated to cardiac anesthesia in the attempt to increase understanding of the nature and significance of this scenario and how to reduce it.
7. Cardiac rehabilitation in Germany.
Science.gov (United States)
Karoff, Marthin; Held, Klaus; Bjarnason-Wehrens, Birna
2007-02-01
The purpose of this review is to give an overview of the rehabilitation measures provided for cardiac patients in Germany and to outline its legal basis and outcomes. In Germany the cardiac rehabilitation system is different from rehabilitation measures in other European countries. Cardiac rehabilitation in Germany since 1885 is based on specific laws and the regulations of insurance providers. Cardiac rehabilitation has predominantly been offered as an inpatient service, but has recently been complemented by outpatient services. A general agreement on the different indications for offering these two services has yet to be reached. Cardiac rehabilitation is mainly offered after an acute cardiac event and bypass surgery. It is also indicated in severe heart failure and special cases of percutaneous coronary intervention. Most patients are men (>65%) and the age at which events occur is increasing. The benefits obtained during the 3-4 weeks after an acute event, and confirmed in numerous studies, are often later lost under 'usual care' conditions. Many attempts have been made by rehabilitation institutions to improve this deficit by providing intensive aftercare. One instrument set up to achieve this is the nationwide institution currently comprising more than 6000 heart groups with approximately 120000 outpatients. After coronary artery bypass grafting or acute coronary syndrome cardiac rehabilitation can usually be started within 10 days. The multidisciplinary rehabilitation team consists of cardiologists, psychologists, exercise therapists, social workers, nutritionists and nurses. The positive effects of cardiac rehabilitation are also important economically, for example, for the improvement of secondary prevention and vocational integration. PMID:17301623
8. Cardiac tumours in infancy
OpenAIRE
2012-01-01
Cardiac tumours in infancy are rare and are mostly benign with rhabdomyomas, fibromas and teratomas accounting for the majority. The presentation depends on size and location of the mass as they tend to cause cavity obstruction or arrhythmias. Most rhabdomyomas tend to regress spontaneously but fibromas and teratomas generally require surgical intervention for severe haemodynamic or arrhythmic complications. Other relatively rare cardiac tumours too are discussed along with an Indian perspect...
9. Infected cardiac hydatid cyst
OpenAIRE
Ceviz, M; Becit, N; Kocak, H.
2001-01-01
A 24 year old woman presented with chest pain and palpitation. The presence of a semisolid mass—an echinococcal cyst or tumour—in the left ventricular apex was diagnosed by echocardiography, computed tomography, and magnetic resonance imaging. The infected cyst was seen at surgery. The cyst was removed successfully by using cardiopulmonary bypass with cross clamp.
Keywords: cardiac hydatid cyst; infected cardiac hydatid cyst
10. [Managing focal incidental renal lesions].
Science.gov (United States)
Nicolau, C; Paño, B; Sebastià, C
2016-01-01
Incidental renal lesions are relatively common in daily radiological practice. It is important to know the different diagnostic possibilities for incidentally detected lesions, depending on whether they are cystic or solid. The management of cystic lesions is guided by the Bosniak classification. In solid lesions, the goal is to differentiate between renal cancer and benign tumors such as fat-poor angiomyolipoma and oncocytoma. Radiologists need to know the recommendations for the management of these lesions and the usefulness of the different imaging techniques and interventional procedures in function of the characteristics of the incidental lesion and the patient's life expectancy.
11. Cardiac applications of optogenetics.
Science.gov (United States)
Ambrosi, Christina M; Klimas, Aleksandra; Yu, Jinzhu; Entcheva, Emilia
2014-08-01
In complex multicellular systems, such as the brain or the heart, the ability to selectively perturb and observe the response of individual components at the cellular level and with millisecond resolution in time, is essential for mechanistic understanding of function. Optogenetics uses genetic encoding of light sensitivity (by the expression of microbial opsins) to provide such capabilities for manipulation, recording, and control by light with cell specificity and high spatiotemporal resolution. As an optical approach, it is inherently scalable for remote and parallel interrogation of biological function at the tissue level; with implantable miniaturized devices, the technique is uniquely suitable for in vivo tracking of function, as illustrated by numerous applications in the brain. Its expansion into the cardiac area has been slow. Here, using examples from published research and original data, we focus on optogenetics applications to cardiac electrophysiology, specifically dealing with the ability to manipulate membrane voltage by light with implications for cardiac pacing, cardioversion, cell communication, and arrhythmia research, in general. We discuss gene and cell delivery methods of inscribing light sensitivity in cardiac tissue, functionality of the light-sensitive ion channels within different types of cardiac cells, utility in probing electrical coupling between different cell types, approaches and design solutions to all-optical electrophysiology by the combination of optogenetic sensors and actuators, and specific challenges in moving towards in vivo cardiac optogenetics.
12. Metastatic Breast Cancer or Multiple Myeloma? Camouflage by Lytic Lesions
Directory of Open Access Journals (Sweden)
Bruce Hough
2010-01-01
Full Text Available We report a case of a female with stage I infiltrating ductal carcinoma who received adjuvant therapy including trastuzumab. One year later she developed lytic lesions and was retreated with trastuzumab that was held after she developed symptomatic heart failure. Lytic lesions were attributed to relapse of breast cancer, and cardiac failure attributed to prior trastuzumab therapy. After complications necessitated multiple hospitalizations, a further workup revealed that the lytic lesions were not metastatic breast cancer but multiple myeloma. Her advanced multiple myeloma was associated with systemic amyloidosis involving gut and heart, which ultimately led to her demise. This report addresses the pitfalls of overlapping symptoms and the question of which patients with suspected metastatic disease should undergo a biopsy.
13. MR findings of the spinal epidural lesions
Energy Technology Data Exchange (ETDEWEB)
Kim, Dong Hun; Lee, Ho Kyu; Shin, Ji Hoon; Choi, Choong Gon; Suh, Dae Chul; Shin, Myung Jin; Rhim, Seung Chul [Ulsan Univ. College of Midicine, Seoul (Korea, Republic of); Park, Sung Tae [Dongguk Univ. College of Midicine, Kyungju (Korea, Republic of)
2001-04-01
The spinal canal takes the form of a series of cylinders designated by their relationship to the meninges and is divided by the dura mater into the epidural or extradural space and intradural space. The epidural space is composed of spinal ligaments, connective and areolar tissue, the epidural venous plexus, lymphatic channels and supporting elements, and various pathologic entities are found there. MR imaging can accurately depict the extent and characteristics of lesions, and in some cases specific diagnosis is possible. In this pictorial essay, we illustrate a variety of spinal epidural lesions and their MR findings.
14. Asymptomatic ischemic cerebral lesions
International Nuclear Information System (INIS)
For the purpose of studying the incidence, pathomorphology and etiology of asymptomatic ischemic cerebral lesions, we carried out a brain MRI study on 65 patients with diabetes mellitus accompanied with hypertension who are thought to belong to a high risk group of ischemic cerebrovascular diseases. Excluding the abnormality of tendon reflex due to diabetic neuropathy, sixty percent of the total patients had some mild neurological signs and symptoms, most of them was discrepancy in tendon reflex. The percentage of the patients in whom MRI disclosed some abnormalities was as high as 70%, they were lacunar stroke, multiple lacunar state, cortical infarct, and patchy high signal lesions visible only in the T2 weighted image. Lacunes or these patchy high signal lesions (considered to be the dilatation of the perivascular space or true lacunes) tended to be found along the border zone or the terminal zone. These results indicate that asymptomatic patients in whom MRI discloses the abnormalities should be considered as candidates for the future onset of multi-infarct. (author)
15. Atypical idiopathic inflammatory demyelinating lesions
DEFF Research Database (Denmark)
Wallner-Blazek, Mirja; Rovira, Alex; Fillipp, Massimo;
2013-01-01
Atypical lesions of a presumably idiopathic inflammatory demyelinating origin present quite variably and may pose diagnostic problems. The subsequent clinical course is also uncertain. We, therefore, wanted to clarify if atypical idiopathic inflammatory demyelinating lesions (AIIDLs) can be class...
16. Exercise, Nrf2 and Antioxidant Signaling in Cardiac Aging.
Science.gov (United States)
2016-01-01
Aging is represented by a progressive decline in cellular functions. The age-related deformities in cardiac behaviors are the loss of cardiac myocytes through apoptosis or programmed cell death. Oxidative stress (OS) and its deleterious consequence contribute to age-related mechanical remodeling, reduced regenerative capacity, and apoptosis in cardiac tissue. The pathogenesis of OS in the elderly can predispose the heart to other cardiac complications such as atherosclerosis, hypertension, ischemic heart disease, cardiac myopathy, and so on. At the molecular level, oxidant-induced activation of Nrf2 (Nuclear erythroid-2-p45-related factor-2), a transcription factor, regulates several genes containing AREs (Antioxidant Response Element) and bring the respective translates to counteract the reactive radicals and establish homeostasis. Myriad of Nrf2 gene knockout studies in various organs such as lung, liver, kidney, brain, etc. have shown that dysregulation of Nrf2 severely affects the oxidant/ROS sensitivity and predispose the system to several pathological changes with aberrant cellular lesions. On the other hand, its gain of function chemical interventions exhibited oxidant stress resistance and cytoprotection. However, thus far, only a few investigations have shown the potential role of Nrf2 and its non-pharmacological induction in cardiac aging. Therefore, here we review the involvement of Nrf2 signaling along with its responses and ramifications on the cascade of OS under acute exercise stress (AES), moderate exercise training (MET), and endurance exercise stress (EES) conditions in the aging heart. PMID:27378947
17. Differential Diagnosis of Cardiac Malposition by Fetal Echocardiography
Institute of Scientific and Technical Information of China (English)
Ying WU; Feng TAO; Tao LIU; Ling ZANG; Shi-long LIU
2009-01-01
Objectives To explore the method and operating skill of fetal echocardiography in diagnosing cardiac malposition. Methods 91 consecutive fetuses were studied (control: 50 cases, cardiac malposition : 41 cases) between 2003 and 2008. The position of fetal heart was evaluated according to the fetal posture and the visceral situs by fetal routine scan-ning. The detailed echocardiography should be performed in the differential diagnosis of cardiac lesions when the heart was found to be abnormal position. Results In the control group, all fetuses were levocardia. 39 cases of cardiac mal-positions were detected by fetal echocardiography, included 25 fetuses with dextrocardia, 6 mesocard, 5 with levover-sion of heart, 3 common heart of conjoined twins and 2 extrathorax heart. Two of dextroversion were missed by fetal routine scanning, but found by autopsy or operation after birth. Conclusions When the abnormal visceral situs was found by fetal routine scanning, there is exceedingly high incidence of cardiac malpositions. Proficiently operating skill of fetal echocardiography is helpful to detect abnormal fetal cardiac position.
18. Imaging findings of multiple infantile hepatic hemangioma associated with cardiac insufficiency
Institute of Scientific and Technical Information of China (English)
Jing-Jing Ye; Yin-Can Shao; Qiang Shu
2014-01-01
Background: Infantile hepatic hemangioma (IHH) as a benign liver tumor in infancy and childhood is commonly associated with high output cardiac failure. The present study aims to describe the imaging findings in a patient who was diagnosed as having multiple IHH with congestive cardiac insuffi ciency. Methods: The imaging findings and clinical manifestations of the patient with multiple IHH associated with cardiac insuffi ciency were retrospectively reviewed. Results: Ultrasonography showed multiple intrahepatic lesions with mixed echoes and markedly expanded hepatic veins and the inferior vena cava of the patient. Echocardiography revealed right heart insufficiency and pulmonary hypertension. Contrast-enhanced MRI showed early mild enhancement of lesions and more obvious delayed enhancement. The patient died after combined therapy of surgery and hormone. Conclusions: The imaging findings of multiple IHH associated with cardiac insufficiency are typical and diagnostic. Early imaging assessment may facilitate the diagnosis and treatment of the disease.
19. A disappearing neonatal skin lesion.
LENUS (Irish Health Repository)
Hawkes, Colin Patrick
2012-01-31
A preterm baby girl was noted at birth to have a firm, raised, non-tender skin lesion located over her right hip. She developed three similar smaller lesions on her ear, buttock and right knee. All lesions had resolved by 2 months of age.
20. Effect of the Spiroiminodihydantoin Lesion on Nucleosome Stability and Positioning.
Science.gov (United States)
Norabuena, Erika M; Barnes Williams, Sara; Klureza, Margaret A; Goehring, Liana J; Gruessner, Brian; Radhakrishnan, Mala L; Jamieson, Elizabeth R; Núñez, Megan E
2016-04-26
DNA is constantly under attack by oxidants, generating a variety of potentially mutagenic covalently modified species, including oxidized guanine base products. One such product is spiroiminodihydantoin (Sp), a chiral, propeller-shaped lesion that strongly destabilizes the DNA helix in its vicinity. Despite its unusual shape and thermodynamic effect on double-stranded DNA structure, DNA duplexes containing the Sp lesion form stable nucleosomes upon being incubated with histone octamers. Indeed, among six different combinations of lesion location and stereochemistry, only two duplexes display a diminished ability to form nucleosomes, and these only by ∼25%; the other four are statistically indistinguishable from the control. Nonetheless, kinetic factors also play a role: when the histone proteins have less time during assembly of the core particle to sample both lesion-containing and normal DNA strands, they are more likely to bind the Sp lesion DNA than during slower assembly processes that better approximate thermodynamic equilibrium. Using DNase I footprinting and molecular modeling, we discovered that the Sp lesion causes only a small perturbation (±1-2 bp) on the translational position of the DNA within the nucleosome. Each diastereomeric pair of lesions has the same effect on nucleosome positioning, but lesions placed at different locations behave differently, illustrating that the location of the lesion and not its shape serves as the primary determinant of the most stable DNA orientation. PMID:27074396
1. Iliopsoas compartment lesions: a radiologic evaluation
Energy Technology Data Exchange (ETDEWEB)
Leao, Alberto Ribeiro de Souza; Amaral, Raquel Portugal Guimaraes; Abud, Thiago Giansante; Demarchi, Guilherme Tadeu Sauaia; Freire Filho, Edison de Oliveira; Novack, Paulo Rogerio; Campos, Flavio do Amaral; Shigueoka, David Carlos; Fernandes, Artur da Rocha Correa; Szejnfeld, Jacob; D' Ippolito, Giuseppe [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil). Dept. de Diagnostico por Imagem]. E-mail: ar.leao@uol.com.br; Santos, Jose Eduardo Mourao [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil)
2007-07-15
The iliopsoas compartment, a posterior boundary of the retroperitoneum, is comprised of the psoas major, psoas minor and iliac muscles. The symptoms picture in patients presenting with pathological involvement of this compartment may show a wide range of nonspecific clinical presentations that may lead to delayed diagnosis. However, in the search of an etiological diagnosis, it is already known that inflammation, tumors, and hemorrhages account for almost all the lesions affecting the iliopsoas compartment. By means of a retrospective analysis of radiological studies in patients with iliopsoas compartment lesions whose diagnosis was confirmed by anatomopathological evaluation or clinical follow-up, we have reviewed its anatomy as well as the main forms of involvement, with the purpose of identifying radiological signs that may help to narrow down the potential differential diagnoses. As each lesion is approached we will discuss the main radiological findings such as presence of gas in pyogenic abscesses, bone destruction and other bone changes of vertebral bodies in lesions secondary to tuberculosis, involvement of fascial planes in cases of neoplasms, and differences in signal density and intensity of hematomas secondary to hemoglobin degradation, among others. So, we have tried to present cases depicting the most frequent lesions involving the iliopsoas compartment, with emphasis on those signs that can lead us to a more specific etiological diagnosis. (author)
2. Novel energy modalities for catheter ablation of cardiac arrhythmias : Pitfalls and possibilities of potent power sources
OpenAIRE
Neven, K.G.E.J.
2014-01-01
The acceptance of catheter ablation as treatment for cardiac arrhythmias is amongst others dependent on its success rate, a high initial success rate will increase physician and patient acceptance. One of the reasons why recurrence of arrhythmia after ablation is substantial is non-transmurality of ablation lesions. Transmurality is essential for conduction block and is depending on many factors, such as tissue ablation duration, thickness of the cardiac wall, ablation technique used, cathete...
3. Sports injuries Lesiones deportivas
Directory of Open Access Journals (Sweden)
Santiago Patiño Giraldo
2007-04-01
Full Text Available Stress generated by sports practice has increased the probability that athletes suffer from acute and chronic injuries. Worldwide, there have been many different investigations concerning the incidence of sport injuries. The different ways in which results have been presented makes it difficult to compare among them. Rates of sports injuries vary between 1.7 and 53 per 1.000 hours of sports practice; 0.8 and 90.9 per 1.000 hours of training; 3.1 and 54.8 per 1.000 hours of competition, and 6.1 and 10.9 per 100 games. The great variability among the incidence rates may be explained by differences among sports, countries, competitive levels, ages and methodology used in the studies. Sports injuries have been defined as those occurring when athletes are practicing sports and that result in tissue alterations or damages, affecting the operation of the corresponding structures. Contact sports such as soccer, rugby, martial arts, basketball, handball and hockey generate greater risk of injuries. The probability of lesions is higher during competition than in training. El estrés generado por la práctica deportiva ha originado una mayor probabilidad de que los atletas presenten lesiones agudas y crónicas. En el ámbito mundial existen diferentes investigaciones acerca de la incidencia de lesiones deportivas. La comparación de sus resultados es difícil por las diferencias en las características de la población y en la forma de reportar los datos, que varía ampliamente entre los estudios (proporciones o tasas de incidencia o tasas por cada 100 ó 1.000 participantes o tasas por horas de juego o por número de partidos jugados. Las tasas varían entre 1,7 y 53 lesiones por 1.000 horas de práctica deportiva, entre 0,8 y 90,9 por 1.000 horas de entrenamiento, entre 3,1 y 54,8 por 1.000 horas de competición y de 6,1 a 10,9 por 100 juegos. La gran variación entre las tasas de incidencia se explica por las diferencias existentes entre los deportes
4. ECLS in Pediatric Cardiac Patients
Science.gov (United States)
Di Nardo, Matteo; MacLaren, Graeme; Marano, Marco; Cecchetti, Corrado; Bernaschi, Paola; Amodeo, Antonio
2016-01-01
Extracorporeal life support (ECLS) is an important device in the management of children with severe refractory cardiac and or pulmonary failure. Actually, two forms of ECLS are available for neonates and children: extracorporeal membrane oxygenation (ECMO) and use of a ventricular assist device (VAD). Both these techniques have their own advantages and disadvantages. The intra-aortic balloon pump is another ECLS device that has been successfully used in larger children, adolescents, and adults, but has found limited applicability in smaller children. In this review, we will present the “state of art” of ECMO in neonate and children with heart failure. ECMO is commonly used in a variety of settings to provide support to critically ill patients with cardiac disease. However, a strict selection of patients and timing of intervention should be performed to avoid the increase in mortality and morbidity of these patients. Therefore, every attempt should be done to start ECLS “urgently” rather than “emergently,” before the presence of dysfunction of end organs or circulatory collapse. Even though exciting progress is being made in the development of VADs for long-term mechanical support in children, ECMO remains the mainstay of mechanical circulatory support in children with complex anatomy, particularly those needing rapid resuscitation and those with a functionally univentricular circulation. With the increase in familiarity with ECMO, new indications have been added, such as extracorporeal cardiopulmonary resuscitation (ECPR). The literature supporting ECPR is increasing in children. Reasonable survival rates have been achieved after initiation of support during active compressions of the chest following in-hospital cardiac arrest. Contraindications to ECLS have reduced in the last 5 years and many centers support patients with functionally univentricular circulations. Improved results have been recently achieved in this complex subset of patients. PMID
5. Analysis of pulmonary coin lesions
Energy Technology Data Exchange (ETDEWEB)
Kim, O; Kim, K. H.; Oh, K. K.; Park, C. Y. [Yonsei University College of Medicine, Seoul (Korea, Republic of)
1979-06-15
For A long time the solitary pulmonary nodule has remained a difficult problem to solve and has attracted a great deal of attension in recent years. Circumscribed coin lesions of the lung were generally peripheral in location with respect to the pulmonary hilus. Because of this, important clinical problem in management and diagnosis arise. Such a lesion is discovered through roentgenologic examination. So the roentgenologists is the first be in a position to offer advise. This presentation is an attempt to correlate a useful diagnosis with roentgenologic findings of pulmonary coin lesion which enables us to get differential diagnosis of benign and malignant lesion. Histologically proven 120 cases of the pulmonary coin lesion during the period of 8 years were reviewed through plain film, tomogram, bronchoscopy, variable laboratory findings, and clinical history. The results are as follows: 1. Male to female sex ratio was 3 : 1. In age distribution, most of the malignant pulmonary coin lesion appeared in 6th decade (39%) and 5th decade (27%). In benign lesion, the most cases were in 3 rd decade. 2. Pathological cell type are as follows: Primary bronchogenic cancer 43.3%, tuberculoma 25.8%, inflammatory lesion 17.5%, benign tumor 10%, and bronchial adenoma, harmartoma, A.V. malformation, mesothelioma, are 1 case respectively. As a result benign and malignant lesion showed equal distribution (49.1% : 50.3%). 3. In symptom analysis ; cough is the most common (43.5%) symptom in malignant lesion, next follows hemoptysis (20.9%) and chest pain (14.5%). In benign lesion, most of the patient (32.7%) did not complain any symptom. 4. In malignant lesion, the most common nodular size was 4 cm (32.3%), and in benign lesion 2 cm sized coin was most common (39.3%). 5. In general, margin of nodule was very sharp and well demarcated in benign lesion (83.3%), and in malignant lesion that was less demarcated and poorly defined. 6. Most case of calcification (82.7%) was seen in benign
6. Cystic Lesions of the Mediastinum.
Science.gov (United States)
Vargas, Daniel; Suby-Long, Thomas; Restrepo, Carlos S
2016-06-01
Cystic lesions are commonly seen in the mediastinum, and they may arise from virtually any organ. The vast majority of these lesions are benign and result in no symptoms. When large, cysts may produce symptoms related to compression of adjacent structures. The most common mediastinal cysts are pericardial and foregut duplication cysts. Both computed tomography and magnetic resonance are routinely used to evaluate these lesions. Although computed tomography offers superior spatial resolution, magnetic resonance is useful in differentiating cysts that contain proteinaceous material from solid lesions. Occasionally, cysts arise from solid lesions, such as thymoma or teratoma. Although cysts are alike in appearance, location helps narrowing the differential diagnoses.
7. Lesiones en corredores amateurs
OpenAIRE
Natale, Vanesa
2011-01-01
Se realizó un estudio tomando como muestra a 100 corredores amateurs de la ciudad de Mar del Plata, en la cual el objetivo general fue determinar cuáles son las patologías más frecuentes en corredores. Correr no es solo un deporte en si mismo sino que tiene elementos de otras actividades deportivas, es decir, que las lesiones de los corredores también son comunes en otros tipos de deportes. El número de deportistas aumenta diariamente y al mismo tiempo aumentan el número de per...
8. Percutaneous Coronary Intervention using a Full Metal Jacket with Drug-eluting Stents: Major Adverse Cardiac Events at One Year
OpenAIRE
Calé, Rita; Teles, Rui Campante; Almeida, Manuel; do Rosário, Ingrid; Sousa, Pedro Jerónimo; Brito, João; Raposo, Luís; Gonçalves, Pedro Araújo; Gabriel, Henrique Mesquita; Mendes, Miguel
2013-01-01
Background The clinical benefit of percutaneous coronary intervention (PCI) for long coronary lesions is unclear; furthermore, concerns have been raised about its safety. Objectives To evaluate the predictors of major adverse cardiac events (MACE) associated with PCI using a full metal jacket (FMJ), defined as overlapping drug-eluting stents (DES) measuring > 60 mm in length, for very long lesions. Methods We enrolled 136 consecutive patients with long coronary lesions requiring FMJ in our si...
9. Pediatric cardiac postoperative care
Directory of Open Access Journals (Sweden)
Auler Jr. José Otávio Costa
2002-01-01
Full Text Available The Heart Institute of the University of São Paulo, Medical School is a referral center for the treatment of congenital heart diseases of neonates and infants. In the recent years, the excellent surgical results obtained in our institution may be in part due to modern anesthetic care and to postoperative care based on well-structured protocols. The purpose of this article is to review unique aspects of neonate cardiovascular physiology, the impact of extracorporeal circulation on postoperative evolution, and the prescription for pharmacological support of acute cardiac dysfunction based on our cardiac unit protocols. The main causes of low cardiac output after surgical correction of heart congenital disease are reviewed, and methods of treatment and support are proposed as derived from the relevant literature and our protocols.
10. The cardiac anxiety questionnaire: cross-validation among cardiac inpatients
NARCIS (Netherlands)
Beek, M.H. van; Oude Voshaar, R.C.; Deelen, F.M. van; Balkom, A.J. van; Pop, G.A.; Speckens, A.E.
2012-01-01
OBJECTIVE: General anxiety symptoms are common in patients with cardiac disease and considered to have an adverse effect on cardiac prognosis. The role of specific cardiac anxiety, however, is still unknown. The aim of this study is to examine the factor structure, reliability, and validity of the D
11. THE CARDIAC ANXIETY QUESTIONNAIRE : CROSS-VALIDATION AMONG CARDIAC INPATIENTS
NARCIS (Netherlands)
van Beek, M. H. C. T.; Voshaar, R. C. Oude; van Deelen, F. M.; van Balkom, A. J. L. M.; Pop, G.; Speckens, A. E. M.
2012-01-01
Objective: General anxiety symptoms are common in patients with cardiac disease and considered to have an adverse effect on cardiac prognosis. The role of specific cardiac anxiety, however, is still unknown. The aim of this study is to examine the factor structure, reliability, and validity of the D
12. Overexpression of Catalase Diminishes Oxidative Cysteine Modifications of Cardiac Proteins.
Directory of Open Access Journals (Sweden)
Chunxiang Yao
Full Text Available Reactive protein cysteine thiolates are instrumental in redox regulation. Oxidants, such as hydrogen peroxide (H2O2, react with thiolates to form oxidative post-translational modifications, enabling physiological redox signaling. Cardiac disease and aging are associated with oxidative stress which can impair redox signaling by altering essential cysteine thiolates. We previously found that cardiac-specific overexpression of catalase (Cat, an enzyme that detoxifies excess H2O2, protected from oxidative stress and delayed cardiac aging in mice. Using redox proteomics and systems biology, we sought to identify the cysteines that could play a key role in cardiac disease and aging. With a 'Tandem Mass Tag' (TMT labeling strategy and mass spectrometry, we investigated differential reversible cysteine oxidation in the cardiac proteome of wild type and Cat transgenic (Tg mice. Reversible cysteine oxidation was measured as thiol occupancy, the ratio of total available versus reversibly oxidized cysteine thiols. Catalase overexpression globally decreased thiol occupancy by ≥1.3 fold in 82 proteins, including numerous mitochondrial and contractile proteins. Systems biology analysis assigned the majority of proteins with differentially modified thiols in Cat Tg mice to pathways of aging and cardiac disease, including cellular stress response, proteostasis, and apoptosis. In addition, Cat Tg mice exhibited diminished protein glutathione adducts and decreased H2O2 production from mitochondrial complex I and II, suggesting improved function of cardiac mitochondria. In conclusion, our data suggest that catalase may alleviate cardiac disease and aging by moderating global protein cysteine thiol oxidation.
13. Perioperative management of cardiac disease.
Science.gov (United States)
Aresti, N A; Malik, A A; Ihsan, K M; Aftab, S M E; Khan, W S
2014-01-01
Pre-existing cardiac disease contributes significantly to morbidity and mortality amongst patients undergoing non cardiac surgery. Patients with pre-existing cardiac disease or with risk factors for it, have as much as a 3.9% risk of suffering a major perioperative cardiac event (Lee et al 1999, Devereaux 2005). Furthermore, the incidence of perioperative myocardial infarction (MI) is increased 10 to 50 fold in patients with previous coronary events (Jassal 2008).
14. Lipid partitioning during cardiac stress.
Science.gov (United States)
Kolwicz, Stephen C
2016-10-01
It is well documented that fatty acids serve as the primary fuel substrate for the contracting myocardium. However, extensive research has identified significant changes in the myocardial oxidation of fatty acids during acute or chronic cardiac stress. As a result, the redistribution or partitioning of fatty acids due to metabolic derangements could have biological implications. Fatty acids can be stored as triacylglycerols, serve as critical components for biosynthesis of phospholipid membranes, and form the potent signaling molecules, diacylglycerol and ceramides. Therefore, the contribution of lipid metabolism to health and disease is more intricate than a balance of uptake and oxidation. In this review, the available data regarding alterations that occur in endogenous cardiac lipid pathways during the pathological stressors of ischemia-reperfusion and pathological hypertrophy/heart failure are highlighted. In addition, changes in endogenous lipids observed in exercise training models are presented for comparison. This article is part of a Special Issue entitled: Heart Lipid Metabolism edited by G.D. Lopaschuk. PMID:27040509
15. Churg-Strauss Syndrome with Cardiac Involvement: A Case Report with CT and MRI Findings
Energy Technology Data Exchange (ETDEWEB)
Lim, Seong Joo; Cho, Young Jun; Kim, Keum; Hwang, Cheol Mok; Kim, Dae Ho [Dept. of Radiology, Konyang University College of Medicine, Daegu (Korea, Republic of); Choi, Eu Gene [Dept. of Internal Medicine, Konyang University College of Medicine, Daegu (Korea, Republic of)
2012-02-15
This is a case report of Churg-Strauss Syndrome (CSS) associated with cardiac involvement which is demonstrated in chest CT and cardiac MRI (CMR) without specific cardiac symptoms. A 32-year-old woman had a 3-year history of bronchial asthma, chronic sinusitis, and otitis media. The patient had various typical findings of CSS. The patient had no specific cardiac symptoms or signs such as chest pain, palpitations, syncope, or murmur, but she had diffuse low attenuation lesions in the inner wall of the left ventricle (LV) in contrast-enhanced CT. This corresponded to the area of subendocardial hyperenhancement in delayed contrast-enhanced CMR images. She was treated with steroids for 2 months. Follow-up delayed contrast-enhanced CMR of the LV showed a decrease in the size of the subendocardial enhancement area, and she had no symptoms. Therefore, the radiologist and clinician both should pay careful attention to observe possible cardiac involvement in case of CSS.
16. The cardiac malpositions.
Science.gov (United States)
Perloff, Joseph K
2011-11-01
Dextrocardia was known in the 17th century and was 1 of the first congenital malformations of the heart to be recognized. Fifty years elapsed before Matthew Baillie published his account of complete transposition in a human of the thoracic and abdominal viscera to the opposite side from what is natural. In 1858, Thomas Peacock stated that "the heart may be congenitally misplaced in various ways, occupying either an unusual position within the thorax, or being situated external to that cavity." In 1915, Maude Abbott described ectopia cordis, and Richard Paltauf's remarkable illustrations distinguished the various types of dextrocardia. In 1928, the first useful classification of the cardiac malpositions was proposed, and in 1966, Elliott et al's radiologic classification set the stage for clinical recognition. The first section of this review deals with the 3 basic cardiac malpositions in the presence of bilateral asymmetry. The second section deals with cardiac malpositions in the presence of bilateral left-sidedness or right-sidedness. Previous publications on cardiac malpositions are replete with an arcane vocabulary that confounds rather than clarifies. Even if the terms themselves are understood, inherent complexity weighs against clarity. This review was designed as a guided tour of an unfamiliar subject.
17. Hepato-cardiac disorders
Institute of Scientific and Technical Information of China (English)
2014-01-01
Understanding the mutual relationship between the liver and the heart is important for both hepatologists and cardiologists. Hepato-cardiac diseases can be classified into heart diseases affecting the liver, liver diseases affecting the heart, and conditions affecting the heart and the liver at the same time. Differential diagnoses of liver injury are extremely important in a cardiologist’s clinical practice calling for collaboration between cardiologists and hepatologists due to the many other diseases that can affect the liver and mimic haemodynamic injury. Acute and chronic heart failure may lead to acute ischemic hepatitis or chronic congestive hepatopathy. Treatment in these cases should be directed to the primary heart disease. In patients with advanced liver disease, cirrhotic cardiomyopathy may develop including hemodynamic changes, diastolic and systolic dysfunctions, reduced cardiac performance and electrophysiological abnormalities. Cardiac evaluation is important for patients with liver diseases especially before and after liver transplantation. Liver transplantation may lead to the improvement of all cardiac changes and the reversal of cirrhotic cardiomyopathy. There are systemic diseases that may affect both the liver and the heart concomitantly including congenital, metabolic and inflammatory diseases as well as alcoholism. This review highlights these hepatocardiac diseases
18. Cardiac effects of vasopressin.
Science.gov (United States)
Pelletier, Jean-Sébastien; Dicken, Bryan; Bigam, David; Cheung, Po-Yin
2014-07-01
Vasopressin is an essential hormone involved in the maintenance of cardiovascular homeostasis. It has been in use therapeutically for many decades, with an emphasis on its vasoconstrictive and antidiuretic properties. However, this hormone has a ubiquitous influence and has specific effects on the heart. Although difficult to separate from its powerful vascular effects in the clinical setting, a better understanding of vasopressin's direct cardiac effects could lead to its more effective clinical use for a variety of shock states by maximizing its therapeutic benefit. The cardiac-specific effects of vasopressin are complex and require further elucidation. Complicating our understanding include the various receptors and secondary messengers involved in vasopressin's effects, which may lead to various results based on differing doses and varying environmental conditions. Thus, there have been contradictory reports on vasopressin's action on the coronary vasculature and on its effect on inotropy. However, beneficial results have been found and warrant further study to expand the potential therapeutic role of vasopressin. This review outlines the effect of vasopressin on the coronary vasculature, cardiac contractility, and on hypertrophy and cardioprotection. These cardiac-specific effects of vasopressin represent an interesting area for further study for potentially important therapeutic benefits. PMID:24621650
19. Cardiac potassium channel subtypes
DEFF Research Database (Denmark)
Schmitt, Nicole; Grunnet, Morten; Olesen, Søren-Peter
2014-01-01
About 10 distinct potassium channels in the heart are involved in shaping the action potential. Some of the K(+) channels are primarily responsible for early repolarization, whereas others drive late repolarization and still others are open throughout the cardiac cycle. Three main K(+) channels...
20. Cardiac pacemaker power sources
International Nuclear Information System (INIS)
A review of chemical and radioisotope batteries used in cardiac pacemakers is presented. The battery systems are examined in terms of longevity, reliability, cost, size and shape, energy density, weight, internal resistance versus time, end-of-life voltage, chemical compatibility, and potential failure mechanisms
1. Small white matter lesion detection in cerebral small vessel disease
Science.gov (United States)
Ghafoorian, Mohsen; Karssemeijer, Nico; van Uden, Inge; de Leeuw, Frank E.; Heskes, Tom; Marchiori, Elena; Platel, Bram
2015-03-01
Cerebral small vessel disease (SVD) is a common finding on magnetic resonance images of elderly people. White matter lesions (WML) are important markers for not only the small vessel disease, but also neuro-degenerative diseases including multiple sclerosis, Alzheimer's disease and vascular dementia. Volumetric measurements such as the "total lesion load", have been studied and related to these diseases. With respect to SVD we conjecture that small lesions are important, as they have been observed to grow over time and they form the majority of lesions in number. To study these small lesions they need to be annotated, which is a complex and time-consuming task. Existing (semi) automatic methods have been aimed at volumetric measurements and large lesions, and are not suitable for the detection of small lesions. In this research we established a supervised voxel classification CAD system, optimized and trained to exclusively detect small WMLs. To achieve this, several preprocessing steps were taken, which included a robust standardization of subject intensities to reduce inter-subject intensity variability as much as possible. A number of features that were found to be well identifying small lesions were calculated including multimodal intensities, tissue probabilities, several features for accurate location description, a number of second order derivative features as well as multi-scale annular filter for blobness detection. Only small lesions were used to learn the target concept via Adaboost using random forests as its basic classifiers. Finally the results were evaluated using Free-response receiver operating characteristic.
2. Mycetoma: Nonvenereal perineal lesions
Directory of Open Access Journals (Sweden)
Gupta Shweta
2010-01-01
Full Text Available Mycetoma is a chronic, granulomatous disease of the skin, and subcutaneous tissue, which sometimes involves muscle, bones, and neighboring organs. It is characterized by tumefaction, abscess formation, and fistulae with discharge of grains from sinuses. Mycetoma can be caused by various species of fungi (eumycetoma and aerobic actinomycetes (actinomycetoma, which occur as saprophytes in soil or plants. A tentative diagnosis sufficient to initiate treatment may be made on the basis of grain color. For instance, melanoid grains are always caused by fungi and ochroid or pale grains by actinomycetes. Although this is not the thumbrule, there are exceptional reports too. As trauma favors infection, most lesions are on the foot and lower leg but they may occur anywhere on the body mimicking actinomycosis. However, lab investigations and culture are important tool to differentiate apart from the clinical picture. We are reporting atypical case with unusual site of presentation (perineum and thigh of mycetoma.
3. Invasive strategy in patients with resuscitated cardiac arrest and ST elevation myocardial infarction
OpenAIRE
Gorjup, Vojka; Noc, Marko; Radsel, Peter
2014-01-01
Coronary artery disease is the most frequent cause of sudden cardiac death. There is general consensus that immediate coronary angiography with percutaneous coronary intervention (PCI) should be performed in all conscious and unconscious patients with ST-elevation myocardial infarction in post-resuscitation electrocardiogram. In these patients acute coronary thrombotic lesion (“ACS” lesion) suitable for PCI is typically present in more than 90%. PCI in these patients is not only feasible and ...
4. Vascular, hepatic and renal lesions by Dirofilaria immitis invasion in dogs
Directory of Open Access Journals (Sweden)
S.A. Pasca
2012-08-01
Full Text Available Morphological investigations were conducted on four bodies of dogs who died due to severe clinical symptoms following a massive invasion of cardiac and pulmonary Dirofilaria. The subjects were monitored clinically and diagnosed serologically positive for the Heartworm disease. The necropsy examination of the cardiovascular system (right ventricle and pulmonary artery revealed the presence of 25 adult parasites in one dog with length ranging between 8 and 33cm. Macroscopically, lesions consistently observed were represented by the right ventricular dilatation and the diffuse wall thickening of the pulmonary artery. Parasitic invasion secondary lesions were present in the lungs, liver and kidneys (cardiac and vascular lesions. The histological examination mainly revealed myocardial injury, vascular (dystrophic, pulmonary (circulatory and inflammatory, hepatic (degenerative and renal (degenerative and inflammatory damage.
5. Endometriosis: A Highly Unexpected Skin Lesion
OpenAIRE
Tolga Dinc
2016-01-01
Endometriosis: A highly unexpected skin lesion Endometriosis is the presence of functional endometrium in anywhere outside of uterin cavity. This clinical entity is relatively common, that 10-15% of fertile women and 6% of post-menopausal women are affected [1,2] . Cutaneous endometriosis is a form of endometriosis and it usually occurs in the incision scar, after gynecological surgeries, cesarean sections and episiotomies [3]. Cutaneous endometriosis is characterized with painful, bluish ...
6. [Corneal lesions in ichthyosis (author's transl)].
Science.gov (United States)
Hammerstein, W; Meiers, H G; Haensch, R
1975-06-01
The authors report about observations they made in two sisters. One sister showed a fibroid degeneration of the cornea, the other a band-shaped keratopathy respectively, together with an ichthyosis and an alopecia as a result of capillary fractures due to pili torti. An autosomal recessive hereditary transmission could be determined. The cutaneous lesion is either an ichthyosis vulgaris, the hereditary transmission of which could not yet be confirmed, or it is a transition form of ichthyosis vulgaris and congenita.
7. Teaching Form as Form
DEFF Research Database (Denmark)
Keiding, Tina Bering
2012-01-01
means that form serves both as the connective value and as the concept for reflection. In other words, form is observed as form, not anything else. The didactical challenge of teaching form as form is accentuated by students’ everyday-based pre-orientation towards function at the expense of form...... reveal highly-structured courses, which alternates systematically between steering and free experimental activities. Consistent with a strong focus on content and the student’s interaction with content, the contributions hardly address the role of the teacher or the interplay between teachers...... and students. This is not to say that teachers do not engage in teaching. They clearly do and obviously play a major role in the progression in course structure and reflection on the student’s learning. My point is that, by neglecting the role of the teacher and the interplay between the teacher and students...
8. Pigmented Lesions of the Vulva
OpenAIRE
Gürol Açıkgöz; Çağlayan Çağdaş Demirci; Ercan Arca
2012-01-01
Pigmented lesions on the vulva are rare and their non specific features cause difficulties in their diagnosis and differential diagnosis. Because of their localization, it is difficult to follow up vulvar lesions, which are generally noticed coincidentally by patients. Vulvar pigmented lesions are classified clinically as macules/papules and patches/plaques to provide ease of the diagnosis. Nevi, angiokeratomas, seborrheic keratosis, melanoma, basal cell carcinoma and squamous cell carcinoma ...
9. Microbiological aspects of endoperiodontal lesion
OpenAIRE
Cristiane Tokunaga; Bruno Monguilhott Crozeta; Mariangela Schmitt Bonato; Beatriz Serrato Coelho; Flares Baratto-Filho; Flávia Sens Fagundes Tomazinho
2013-01-01
Introduction: The endoperiodontal lesion occurs when a tooth undergoing endodontic disease is united to a periodontal lesion with apical progression. Many times, the differential diagnosis between the endodontic and periodontal disease can be of difficult execution and the correct diagnosis and planing of the treatment is of main importance for a good prognosis Objective: To identify the main microorganisms within the lesion of endodontic and periodontal origin and correlate them with the en...
10. MALIGNANCY IN LARGE COLORECTAL LESIONS
Directory of Open Access Journals (Sweden)
Carlos Eduardo Oliveira dos SANTOS
2014-09-01
Full Text Available Context The size of colorectal lesions, besides a risk factor for malignancy, is a predictor for deeper invasion Objectives To evaluate the malignancy of colorectal lesions ≥20 mm. Methods Between 2007 and 2011, 76 neoplasms ≥20 mm in 70 patients were analyzed Results The mean age of the patients was 67.4 years, and 41 were women. Mean lesion size was 24.7 mm ± 6.2 mm (range: 20 to 50 mm. Half of the neoplasms were polypoid and the other half were non-polypoid. Forty-two (55.3% lesions were located in the left colon, and 34 in the right colon. There was a high prevalence of III L (39.5% and IV (53.9% pit patterns. There were 72 adenomas and 4 adenocarcinomas. Malignancy was observed in 5.3% of the lesions. Thirty-three lesions presented advanced histology (adenomas with high-grade dysplasia or early adenocarcinoma, with no difference in morphology and site. Only one lesion (1.3% invaded the submucosa. Lesions larger than 30 mm had advanced histology (P = 0.001. The primary treatment was endoscopic resection, and invasive carcinoma was referred to surgery. Recurrence rate was 10.6%. Conclusions Large colorectal neoplasms showed a low rate of malignancy. Endoscopic treatment is an effective therapy for these lesions.
Directory of Open Access Journals (Sweden)
2014-03-01
Full Text Available Introduction : Radiotherapy, an important tool in multimodal oncologic treatment, can cause radio-induced brain lesion development after a long period of time following irradiation.
12. MRI of fetal acquired brain lesions
Energy Technology Data Exchange (ETDEWEB)
Prayer, Daniela [Department of Radiodiagnostics, Medical University of Vienna (Austria)]. E-mail: daniela.prayer@meduniwien.ac.at; Brugger, Peter C. [Center of Anatomy and Cell Biology, Medical University of Vienna (Austria); Kasprian, Gregor [Department of Radiodiagnostics, Medical University of Vienna (Austria); Witzani, Linde [Department of Radiodiagnostics, Medical University of Vienna (Austria); Helmer, Hanns [Department of Obstetrics and Gynecology, Medical University of Vienna (Austria); Dietrich, Wolfgang [Department of Neurosurgery, Medical University of Vienna (Austria); Eppel, Wolfgang [Department of Obstetrics and Gynecology, Medical University of Vienna (Austria); Langer, Martin [Department of Obstetrics and Gynecology, Medical University of Vienna (Austria)
2006-02-15
Acquired fetal brain damage is suspected in cases of destruction of previously normally formed tissue, the primary cause of which is hypoxia. Fetal brain damage may occur as a consequence of acute or chronic maternal diseases, with acute diseases causing impairment of oxygen delivery to the fetal brain, and chronic diseases interfering with normal, placental development. Infections, metabolic diseases, feto-fetal transfusion syndrome, toxic agents, mechanical traumatic events, iatrogenic accidents, and space-occupying lesions may also qualify as pathologic conditions that initiate intrauterine brain damage. MR manifestations of acute fetal brain injury (such as hemorrhage or acute ischemic lesions) can easily be recognized, as they are hardly different from postnatal lesions. The availability of diffusion-weighted sequences enhances the sensitivity in recognizing acute ischemic lesions. Recent hemorrhages are usually readily depicted on T2 (*) sequences, where they display hypointense signals. Chronic fetal brain injury may be characterized by nonspecific changes that must be attributable to the presence of an acquired cerebral pathology. The workup in suspected acquired fetal brain injury also includes the assessment of extra-CNS organs that may be affected by an underlying pathology. Finally, the placenta, as the organ that mediates oxygen delivery from the maternal circulation to the fetus, must be examined on MR images.
13. MRI of fetal acquired brain lesions
International Nuclear Information System (INIS)
Acquired fetal brain damage is suspected in cases of destruction of previously normally formed tissue, the primary cause of which is hypoxia. Fetal brain damage may occur as a consequence of acute or chronic maternal diseases, with acute diseases causing impairment of oxygen delivery to the fetal brain, and chronic diseases interfering with normal, placental development. Infections, metabolic diseases, feto-fetal transfusion syndrome, toxic agents, mechanical traumatic events, iatrogenic accidents, and space-occupying lesions may also qualify as pathologic conditions that initiate intrauterine brain damage. MR manifestations of acute fetal brain injury (such as hemorrhage or acute ischemic lesions) can easily be recognized, as they are hardly different from postnatal lesions. The availability of diffusion-weighted sequences enhances the sensitivity in recognizing acute ischemic lesions. Recent hemorrhages are usually readily depicted on T2 (*) sequences, where they display hypointense signals. Chronic fetal brain injury may be characterized by nonspecific changes that must be attributable to the presence of an acquired cerebral pathology. The workup in suspected acquired fetal brain injury also includes the assessment of extra-CNS organs that may be affected by an underlying pathology. Finally, the placenta, as the organ that mediates oxygen delivery from the maternal circulation to the fetus, must be examined on MR images
14. Cardiac allograft immune activation: current perspectives
OpenAIRE
Chang D; Kobashigawa J
2014-01-01
David Chang, Jon Kobashigawa Cedars-Sinai Heart Institute, Los Angeles, CA, USA Abstract: Heart transplant remains the most durable option for end-stage heart disease. Cardiac allograft immune activation and heart transplant rejection remain among the main complications limiting graft and recipient survival. Mediators of the immune system can cause different forms of rejection post-heart transplant. Types of heart transplant rejection include hyperacute rejection, cellular rejection, antibod...
15. Cardiac fusion and complex congenital cardiac defects in thoracopagus twins: diagnostic value of cardiac CT
Energy Technology Data Exchange (ETDEWEB)
Goo, Hyun Woo [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Park, Jeong-Jun [University of Ulsan College of Medicine, Asan Medical Center, Department of Pediatric Cardiac Surgery, Seoul (Korea, Republic of); Kim, Ellen Ai-Rhan [University of Ulsan College of Medicine, Asan Medical Center, Division of Neonatology, Department of Pediatrics, Seoul (Korea, Republic of); Won, Hye-Sung [University of Ulsan College of Medicine, Asan Medical Center, Department of Obstetrics and Gynecology, Seoul (Korea, Republic of)
2014-09-15
Most thoracopagus twins present with cardiac fusion and associated congenital cardiac defects, and assessment of this anatomy is of critical importance in determining patient care and outcome. Cardiac CT with electrocardiographic triggering provides an accurate and quick morphological assessment of both intracardiac and extracardiac structures in newborns, making it the best imaging modality to assess thoracopagus twins during the neonatal period. In this case report, we highlight the diagnostic value of cardiac CT in thoracopagus twins with an interatrial channel and complex congenital cardiac defects. (orig.)
16. Intra-cardiac distribution of late gadolinium enhancement in cardiac sarcoidosis and dilated cardiomyopathy
Science.gov (United States)
Sano, Makoto; Satoh, Hiroshi; Suwa, Kenichiro; Saotome, Masao; Urushida, Tsuyoshi; Katoh, Hideki; Hayashi, Hideharu; Saitoh, Takeji
2016-01-01
Cardiac involvement of sarcoid lesions is diagnosed by myocardial biopsy which is frequently false-negative, and patients with cardiac sarcoidosis (CS) who have impaired left ventricular (LV) systolic function are sometimes diagnosed with dilated cardiomyopathy (DCM). Late gadolinium enhancement (LE) in magnetic resonance imaging is now a critical finding in diagnosing CS, and the novel Japanese guideline considers myocardial LE to be a major criterion of CS. This article describes the value of LE in patients with CS who have impaired LV systolic function, particularly the diagnostic and clinical significance of LE distribution in comparison with DCM. LE existed at all LV segments and myocardial layers in patients with CS, whereas it was localized predominantly in the midwall of basal to mid septum in those with DCM. Transmural (nodular), circumferential, and subepicardial and subendocardial LE distribution were highly specific in patients with CS, whereas the prevalence of striated midwall LE were high both in patients with CS and with DCM. Since sarcoidosis patients with LE have higher incidences of heart failure symptoms, ventricular tachyarrhythmia and sudden cardiac death, the analyses of extent and distribution of LE are crucial in early diagnosis and therapeutic approach for patients with CS. PMID:27721933
17. Characteristics of polypoid lesions in patients undergoing microsurgery of the larynx
OpenAIRE
Ido Filho, Jorge Massaaki; Carvalho, Bettina; Mizoguchi, Flavio Massao; Catani, Guilherme Simas do Amaral; Macedo Filho, Evaldo Dacheux de; Malafaia, Osvaldo; Stahlke Jr., Henrique Jorge
2014-01-01
Summary Introduction: Dysphonia is the main symptom of lesions that affect the vocal tract. Many of those lesions may require surgical treatment. Polyps are one of the most common forms of vocal cord lesions and the most prevalent indication for laryngeal microsurgery. There are different types of polyps, and their different characteristics can indicate different prognosis and treatments. Aim: To conduct a comparative study of polypoid lesions (angiomatous and gelatinous) in patients undergoi...
18. Sudden Cardiac Death
Directory of Open Access Journals (Sweden)
Yipsy María Gutiérrez Báez
2015-09-01
Full Text Available Since the second half of the twentieth century, dying suddenly due to heart-related problems has become the main health issue in all countries where infectious diseases are not prevalent. Sudden death from cardiac causes is an important global health problem. Major databases were searched for the leading causes of sudden cardiac death. It has been demonstrated that there is a group of hereditary diseases with structural alterations or without apparent organic cause that explains many cases of sudden death in young people, whether related or not to physical exertion. Certain population groups are at higher risk for this disease. They are relatively easy to identify and can be the target of primary prevention measures.
19. Senile dementia of the Binswanger type: a vascular form of dementia in the elderly
International Nuclear Information System (INIS)
Computed tomography and magnetic resonance imaging in the elderly have demonstrated the common occurrence of deep white-matter lesions in the aging brain. These radiologic lesions (leukoaraiosis) may represent an early marker of dementia. At autopsy, an ischemic periventricular leukoencephalopathy (Binswanger's disease) has been found in most cases. The clinical spectrum of Binswanger's disease appears to range from asymptomatic radiologic lesions to dementia with focal deficits, frontal signs, pseudobulbar palsy, gait difficulties, and urinary incontinence. The name senile dementia of the Binswanger type (SDBT) is proposed for this poorly recognized, vascular form of subcortical dementia. The SDBT probably results from cortical disconnections most likely caused by hypoperfusion. In contrast, multi-infarct dementia is correlated with multiple large and small strokes that cause a loss of over 50 to 100 mL of brain volume. The periventricular white matter is a watershed area irrigated by long, penetrating medullary arteries. Risk factors for SDBT are small-artery diseases, such as hypertension and amyloid angiopathy, impaired autoregulation of cerebral blood flow in the elderly, and periventricular hypoperfusion due to cardiac failure, arrhythmias, and hypotension. The SDBT may be a potentially preventable and treatable form of dementia
20. Senile dementia of the Binswanger type: a vascular form of dementia in the elderly
Energy Technology Data Exchange (ETDEWEB)
Roman, G.C.
1987-10-02
Computed tomography and magnetic resonance imaging in the elderly have demonstrated the common occurrence of deep white-matter lesions in the aging brain. These radiologic lesions (leukoaraiosis) may represent an early marker of dementia. At autopsy, an ischemic periventricular leukoencephalopathy (Binswanger's disease) has been found in most cases. The clinical spectrum of Binswanger's disease appears to range from asymptomatic radiologic lesions to dementia with focal deficits, frontal signs, pseudobulbar palsy, gait difficulties, and urinary incontinence. The name senile dementia of the Binswanger type (SDBT) is proposed for this poorly recognized, vascular form of subcortical dementia. The SDBT probably results from cortical disconnections most likely caused by hypoperfusion. In contrast, multi-infarct dementia is correlated with multiple large and small strokes that cause a loss of over 50 to 100 mL of brain volume. The periventricular white matter is a watershed area irrigated by long, penetrating medullary arteries. Risk factors for SDBT are small-artery diseases, such as hypertension and amyloid angiopathy, impaired autoregulation of cerebral blood flow in the elderly, and periventricular hypoperfusion due to cardiac failure, arrhythmias, and hypotension. The SDBT may be a potentially preventable and treatable form of dementia.
1. Nonsurgical management of periapical lesions
Directory of Open Access Journals (Sweden)
Fernandes Marina
2010-01-01
Full Text Available Periapical lesions develop as sequelae to pulp disease. They often occur without any episode of acute pain and are discovered on routine radiographic examination. The incidence of cysts within periapical lesions varies between 6 and 55%. The occurrence of periapical granulomas ranges between 9.3 and 87.1%, and of abscesses between 28.7 and 70.07%. It is accepted that all inflammatory periapical lesions should be initially treated with conservative nonsurgical procedures. Studies have reported a success rate of up to 85% after endodontic treatment of teeth with periapical lesions. A review of literature was performed by using electronic and hand searching methods for the nonsurgical management of periapical lesions. Various methods can be used in the nonsurgical management of periapical lesions: the conservative root canal treatment, decompression technique, active nonsurgical decompression technique, aspiration-irrigation technique, method using calcium hydroxide, Lesion Sterilization and Repair Therapy, and the Apexum procedure. Monitoring the healing of periapical lesions is essential through periodic follow-up examinations.
2. Inherited cardiac disease
Directory of Open Access Journals (Sweden)
Philippe Charron
2012-06-01
Full Text Available Major advances have been achieved over the two last decades in the field of genetic cardiovascular diseases, not only through increased recognition and understanding of underlying molecular defects but also through rapid translation of knowledge into clinical practice. Genetic counseling and organization of cardiac family screening has become part of the medical management of these diseases, and these should be performed systematically unless an acquired cause has been diagnosed...
3. Cardiac Tissue Engineering
OpenAIRE
2009-01-01
We hypothesized that clinically sized (1-5 mm thick),compact cardiac constructs containing physiologically high density of viable cells (~108 cells/cm3) can be engineered in vitro by using biomimetic culture systems capable of providing oxygen transport and electrical stimulation, designed to mimic those in native heart. This hypothesis was tested by culturing rat heart cells on polymer scaffolds, either with perfusion of culture medium (physiologic interstitial velocity, supplementation of p...
4. Cardiac developmental toxicity
OpenAIRE
Mahler, Gretchen J.; Jonathan T Butcher
2011-01-01
Congenital heart disease is a highly prevalent problem with mostly unknown origins. Many cases of CHD likely involve an environmental exposure coupled with genetic susceptibility, but practical and ethical considerations make nongenetic causes of CHD difficult to assess in humans. The development of the heart is highly conserved across all vertebrate species, making animal models an excellent option for screening potential cardiac teratogens. This review will discuss exposures known to cause ...
5. Assessing Depression in Cardiac Patients: What Measures Should Be Considered?
Directory of Open Access Journals (Sweden)
M. Ceccarini
2014-01-01
Full Text Available It is highly recommended to promptly assess depression in heart disease patients as it represents a crucial risk factor which may result in premature deaths following acute cardiac events and a more severe psychopathology, even in cases of subsequent nonfatal cardiac events. Patients and professionals often underestimate or misjudge depressive symptomatology as cardiac symptoms; hence, quick, reliable, and early mood changes assessments are warranted. Failing to detect depressive signals may have detrimental effects on these patients’ wellbeing and full recovery. Choosing gold-standard depression investigations in cardiac patients that fit a hospitalised cardiac setting well is fundamental. This paper will examine eight well established tools following Italian and international guidelines on mood disorders diagnosis in cardiac patients: the Hospital Anxiety and Depression Scale (HADS, the Cognitive Behavioural Assessment Hospital Form (CBA-H, the Beck Depression Inventory (BDI, the two and nine-item Patient Health Questionnaire (PHQ-2, PHQ-9, the Depression Interview and Structured Hamilton (DISH, the Hamilton Rating Scale for Depression (HAM-D/HRSD, and the Composite International Diagnostic Interview (CIDI. Though their strengths and weaknesses may appear to be homogeneous, the BDI-II and the PHQ are more efficient towards an early depression assessment within cardiac hospitalised patients.
6. Cine MR imaging-current use in cardiac diagnosis
International Nuclear Information System (INIS)
This paper reviews the current status of cine MR imaging of the heart with special attention to the assessment of cardiac function. Cine MR provides tomographic sectional images with clear distinction between myocardium and flowing blood, and allows accurate volumetry of the cardiac chambers at specific points of the cardiac cycle. From these volume measurements parameters for the cardiac function, such as stroke volumem, ejection fraction, regurgitant fraction and shunt volum are calculated. While determination of chamber volumes can be done using any imaging plane, regional wall motion and wall thickening are evaluated with the short axis images. These images are readily obtained by orienting the slice selective gradient perpendicular to the long axis of the left ventricle. Left ventricular meridional wall stress is also calculated from cine MR images and noninvasive measurements of peak- and end-systolic pressure. Wall stress is an indicator of myocardial function in response to after load and can be used for monitoring patients with myocardial disease, regurgitant valvular disease and hypertension, and might be used to quantitatively assess the response of these diseases to therapy. Diseases causing hypertrophy of the ventricles, such as valvular stenosis, systemic or pulmonary hypertension and hypertrophic cardiomyopathy, can be monitored with cine MR by measuring the myocardial mass. A signal void from high velocity jets is caused by regurgitant or stenotic valvular lesion as well as flow across ventricular or atrial septal defects. Measurement of the dimension of the signal void have been correlated with the severity of regurgitation and can be used for semi-quantitation of these lesions. Due to the inherent contrast between blood and myocardium, high temporal resolution, and acquisition of tomographic images encompassing the entire heart, cine MR can serve as a comprehensive cardiac imaging modality that provides quantitative evaluation of anatomy and
7. Cardiac hybrid imaging
Energy Technology Data Exchange (ETDEWEB)
Gaemperli, Oliver [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); University Hospital Zurich, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland)
2014-05-15
Hybrid cardiac single photon emission computed tomography (SPECT)/CT imaging allows combined assessment of anatomical and functional aspects of cardiac disease. In coronary artery disease (CAD), hybrid SPECT/CT imaging allows detection of coronary artery stenosis and myocardial perfusion abnormalities. The clinical value of hybrid imaging has been documented in several subsets of patients. In selected groups of patients, hybrid imaging improves the diagnostic accuracy to detect CAD compared to the single imaging techniques. Additionally, this approach facilitates functional interrogation of coronary stenoses and guidance with regard to revascularization procedures. Moreover, the anatomical information obtained from CT coronary angiography or coronary artery calcium scores (CACS) adds prognostic information over perfusion data from SPECT. The use of cardiac hybrid imaging has been favoured by the dissemination of dedicated hybrid systems and the release of dedicated image fusion software, which allow simple patient throughput for hybrid SPECT/CT studies. Further technological improvements such as more efficient detector technology to allow for low-radiation protocols, ultra-fast image acquisition and improved low-noise image reconstruction algorithms will be instrumental to further promote hybrid SPECT/CT in research and clinical practice. (orig.)
8. Establishing a clinical cardiac MRI service
International Nuclear Information System (INIS)
After several years of research development cardiovascular MRI has evolved into a widely accepted clinical tool. It offers important diagnostic and prognostic information for a variety of clinical indications, which include ischaemic heart disease, cardiomyopathies, valvular dysfunction and congenital heart disorders. It is a safe non-invasive technique that employs a variety of imaging sequences optimized for temporal or spatial resolution, tissue-specific contrast, flow quantification or angiography. Cardiac MRI offers specific advantages over conventional imaging techniques for a significant number of patients. The demand for cardiac MRI studies from cardiothoracic surgeons, cardiologists and other referrers is likely to continue to rise with pressure for more widespread local service provision. Setting up a cardiac MRI service requires careful consideration regarding funding issues and how it will be integrated with existing service provision. The purchase of cardiac phased array coils, monitoring equipment and software upgrades must also be considered, as well as the training needs of those involved. The choice of appropriate imaging protocols will be guided by operator experience, clinical indication and equipment capability, and is likely to evolve as the service develops. Post-processing and offline analysis form a significant part of the time taken to report studies and an efficient method of providing quantitative reports is an important requirement. Collaboration between radiologists and cardiologists is needed to develop a successful service and multi-disciplinary meetings are key component of this. This review will explore these issues from our perspective of a new clinical cardiac MRI service operating over its first year in a teaching hospital imaging department
9. Biatrial Cardiac Metastases in a Patient with Uterine Cervix Malignant Melanoma
Directory of Open Access Journals (Sweden)
Caglayan Geredeli
2015-01-01
Full Text Available Primary malignant melanomas of uterine cervix are quite rarely seen neoplasms, and long-life prognosis of patients with this disease is poor. Immunohistochemical methods and exclusion of other primary melanoma sites are used to confirm the diagnosis. As with other melanomas, cervix malignant melanomas may also cause cardiac metastases. Cardiac metastases are among rarely seen but more commonly encountered cases, compared to primary cardiac tumors. Here, we present a case of biatrial cardiac metastases in a 73-year-old patient with uterine cervix malignant melanomas. The patient underwent echocardiography, cardiac magnetic resonance imaging, and computed tomography. Our report shows the importance of advanced diagnostic techniques, such as cardiac magnetic resonance, not only for the detection of cardiac masses, but for a better anatomic definition and tissue characterization. Although the cases of malignant melanomas leading to multiple cardiac metastasis were reported in literature, the metastatic concurrence of malignant melanomas in both right and left atriums is quite rarely encountered as metastatic malignant melanomas. Also, another intriguing point in our case is that the primary lesion of our case was stemmed from uterine cervix, but not skin.
10. Study of pregnancy outcome in women with cardiac disease: a retrospective analysis
Directory of Open Access Journals (Sweden)
Kiran Pandey
2016-10-01
Conclusions: Heart disease in pregnancy is a high risk condition and has a major impact on pregnancy outcome. Rheumatic heart disease being the prominent cardiac lesion. Fetomaternal mortality and morbidity can be reduced with proper antenatal, intrapartum and postnatal care in conjunction with cardiologist and neonatologist. [Int J Reprod Contracept Obstet Gynecol 2016; 5(10.000: 3537-3541
11. Colonic malakoplakia in a cardiac transplant recipient
Directory of Open Access Journals (Sweden)
2014-08-01
Full Text Available Malakoplakia is a rare inflammatory condition which is usually seen in the urogenital tract and less commonly in the gastrointestinal tract. Gastrointestinal malakoplakia may be associated with organ transplantation. There are previously only three reported cases of malakoplakia in cardiac transplant recipient. We report a case of colonic malakoplakia in a 38‑year‑old male who underwent cardiac transplantation for dilated cardiomyopathy 4 years previously and who had been on tacrolimus and mycophenolate. The patient presented with history of diarrhea associated with fecal incontinence for the past 6 months. Ileocolonoscopic examination was within normal limits. A rectal biopsy was done to exclude microscopic pathology. Microscopy revealed expansion of the lamina propria by histiocytes admixed with a few lymphocytes. The histiocytes showed granular eosinophilic cytoplasm with intracytoplasmic presence of Michaelis‑Gutmann bodies, rounded basophilic laminated structures having central core with a targetoid appearance. These stained positively for Von kossa stain for calcium and were diagnostic for malakoplakia. Although rare, malakoplakia may be associated with chronic diarrhea even if there are no macroscopic lesions seen during colonoscopy. The patient’s symptoms resolved with long‑term ciprofloxacin therapy
12. Drug-related cardiac valve disease.
Science.gov (United States)
2013-12-01
Cardiac valve disease can involve one or more of the four heart valves. Chronic valve damage may remain asymptomatic for long periods but ultimately leads to haemodynamic overload of the heart. The most common causes of valve disease are rheumatic diseases, infections, chronic renal failure, malformations, and genetic diseases. Valve disease is often attributed to degeneration with no known cause.The frequency of drug-related valve disease has long been underestimated. Most implicated drugs have serotonergic properties, such as fenfluramine-derived amphetamines, including benfluorex. Rye ergot derivatives can also be implicated: these include dopamine agonists (bromocriptine, lisuride, pergolide and cabergoline), migraine treatments (methysergide, ergotamine and dihydroergotamine), and drugs used for cognitive and neurosensory deficits (nicergoline, dihydroergocryptine, etc.). "Ecstasy", an amphetamine, is sometimes also involved. The risk increases after a few months of exposure. Drug withdrawal is sometimes followed by an improvement. Patients exposed to a drug known to cause valve damage should be informed of the risk and receive long-term monitoring to detect these lesions before they become irreversible. The possible role of a drug should always be considered when cardiac valve disease is diagnosed, in order to facilitate active research and to avoid exposing other patients to this risk. PMID:24600729
13. Systemic juvenile xanthogranuloma with multiple central nervous system lesions
Directory of Open Access Journals (Sweden)
Ali Meshkini
2012-01-01
Full Text Available Juvenile xanthogranulomatosis (JXG is an uncommon histiocytic disorder that is usually benign and limited to the skin. The systemic form of JXG is rare and may be associated with severe morbidity and mortality especially in central nervous system (CNS involvement. Here, we describe a six-year-old boy with disseminated skin lesions and neurological signs and symptoms. Diagnostic work up revealed multiple brain lesions. A skin biopsy and a stereotactic brain biopsy considered suggestive of systemic JXG. Treatment with prednisolone, vinblastine and methotrexate was successful with regression of skin and CNS lesions. The patient has been in remission for almost three years.
14. Indeterminacy of Spatiotemporal Cardiac Alternans
CERN Document Server
Zhao, Xiaopeng
2007-01-01
Cardiac alternans, a beat-to-beat alternation in action potential duration (at the cellular level) or in ECG morphology (at the whole heart level), is a marker of ventricular fibrillation, a fatal heart rhythm that kills hundreds of thousands of people in the US each year. Investigating cardiac alternans may lead to a better understanding of the mechanisms of cardiac arrhythmias and eventually better algorithms for the prediction and prevention of such dreadful diseases. In paced cardiac tissue, alternans develops under increasingly shorter pacing period. Existing experimental and theoretical studies adopt the assumption that alternans in homogeneous cardiac tissue is exclusively determined by the pacing period. In contrast, we find that, when calcium-driven alternans develops in cardiac fibers, it may take different spatiotemporal patterns depending on the pacing history. Because there coexist multiple alternans solutions for a given pacing period, the alternans pattern on a fiber becomes unpredictable. Usin...
15. [Onychomatricoma, a rare lesion of the nail].
Science.gov (United States)
Pommepuy, Isabelle; Roblet, Denis; Blaise, Sophie; Delage-Corre, Manuela; Bonnetblanc, Jean-Marie; Fayol, Jacqueline; Labrousse, François
2004-09-01
Onychomatricoma is a rare fibroepithelial lesion of the nail matrix with peculiar clinical and histological features. Clinically, it is characterized by a longitudinal band of yellow thickening of the nail plate with transverse overcurvature and splinter hemorrhages. Nail avulsion exposes a villous tumor of the matrix with filamentous digitations extending into multiple holes of the nail plate. Histologically, a thick keratogenous zone forms a thickened nail plate. The lesion in its proximal portion is characterized by deep epithelial invaginations and by a stroma organized in two layers. The distal zone corresponds to multiple fibroepithelial projections extending into the nail plate. The diagnosis can be difficult in the presence of misleading clinical features or when the specimen is incomplete or examined with an improper orientation. Surgical resection is the recommended treatment. PMID:15567955
16. Getting to the heel of the problem: plantar fascia lesions
International Nuclear Information System (INIS)
Heel pain is a frequent disabling symptom. Clinical diagnosis is often difficult with a large range of possible diagnoses. Lesions of the plantar fascia form an important group. We present a review describing the common lesions of the plantar fascia, including plantar fasciitis, plantar fascia rupture, plantar fibromatosis, and plantar xanthoma, and illustrate them with appropriate magnetic resonance imaging (MRI) and ultrasound imaging. We also address foreign-body reactions, enthesopathy, and diabetic fascial disease.
17. Getting to the heel of the problem: plantar fascia lesions
Energy Technology Data Exchange (ETDEWEB)
Jeswani, T. [Department of Radiology, Worthing and Southlands Hospitals, West Sussex (United Kingdom); Morlese, J. [Department of Radiology, Royal Free Hospital, Pond street, London, NW3 2QG (United Kingdom); McNally, E.G. [Department of Radiology, Nuffield Orthopaedic Centre, Oxford (United Kingdom)], E-mail: eugene.mcnally@gmail.com
2009-09-15
Heel pain is a frequent disabling symptom. Clinical diagnosis is often difficult with a large range of possible diagnoses. Lesions of the plantar fascia form an important group. We present a review describing the common lesions of the plantar fascia, including plantar fasciitis, plantar fascia rupture, plantar fibromatosis, and plantar xanthoma, and illustrate them with appropriate magnetic resonance imaging (MRI) and ultrasound imaging. We also address foreign-body reactions, enthesopathy, and diabetic fascial disease.
18. Sudden Cardiac Death in Athletes.
Science.gov (United States)
Wasfy, Meagan M; Hutter, Adolph M; Weiner, Rory B
2016-01-01
There are clear health benefits to exercise; even so, patients with cardiac conditions who engage in exercise and athletic competition may on rare occasion experience sudden cardiac death (SCD). This article reviews the epidemiology and common causes of SCD in specific athlete populations. There is ongoing debate about the optimal mechanism for SCD prevention, specifically regarding the inclusion of the ECG and/or cardiac imaging in routine preparticipation sports evaluation. This controversy and contemporary screening recommendations are also reviewed. PMID:27486488
19. Comparative Analysis of Telomerase Activity in CD117+CD34+ Cardiac Telocytes with Bone Mesenchymal Stem Cells, Cardiac Fibroblasts and Cardiomyocytes
Institute of Scientific and Technical Information of China (English)
Yuan-Yuan Li; Shan-Shan Lu; Ting Xu; Hong-Qi Zhang; Hua Li
2015-01-01
Background:This study characterized the cardiac telocyte (TC) population both in vivo and in vitro,and investigated its telomerase activity related to mitosis.Methods:Using transmission electron microscopy and a phase contrast microscope,the typical morphological features of cardiac TCs were observed;by targeting the cell surface proteins CD 1 17 and CD34,CD 117+CD34+ cardiac TCs were sorted via flow cytometry and validated by immunofluorescence based on the primary cell culture.Then the optimized basal nutrient medium for selected population was examined with the cell counting kit 8.Under this conditioned medium,the process of cell division was captured,and the telomerase activity ofCD 117+CD34+ cardiac TCs was detected in comparison with bone mesenchymal stem cells (BMSCs),cardiac fibroblasts (CFBs),cardiomyocytes (CMs).Results:Cardiac TCs projected characteristic telopodes with thin segments (podomers) in alternation with dilation (podoms).In addition,64％ of the primary cultured cardiac TCs were composed of CD 117+CD34+ cardiac TCs;which was verified by immunofluorescence.In a live cell imaging system,CD 117+CD34+ cardiac TCs were observed to enter into cell division in a short time,followed by an significant invagination forming across the middle of the cell body.Using a real-time quantitative telomeric-repeat amplification assay,the telomerase concentration in CD117+CD34+ cardiac TCs was obviously lower than in BMSCs and CFBs,and significantly higher than in CMs.Conclusions:Cardiac TCs represent a unique cell population and CD117+CD34+ cardiac TCs have relative low telomerase activity that differs from BMSCs,CFBs and CMs and thus they might play an important role in maintaining cardiac homeostasis.
20. Comparative Analysis of Telomerase Activity in CD117+CD34+ Cardiac Telocytes with Bone Mesenchymal Stem Cells, Cardiac Fibroblasts and Cardiomyocytes
Science.gov (United States)
Li, Yuan-Yuan; Lu, Shan-Shan; Xu, Ting; Zhang, Hong-Qi; Li, Hua
2015-01-01
Background: This study characterized the cardiac telocyte (TC) population both in vivo and in vitro, and investigated its telomerase activity related to mitosis. Methods: Using transmission electron microscopy and a phase contrast microscope, the typical morphological features of cardiac TCs were observed; by targeting the cell surface proteins CD117 and CD34, CD117+CD34+ cardiac TCs were sorted via flow cytometry and validated by immunofluorescence based on the primary cell culture. Then the optimized basal nutrient medium for selected population was examined with the cell counting kit 8. Under this conditioned medium, the process of cell division was captured, and the telomerase activity of CD117+CD34+ cardiac TCs was detected in comparison with bone mesenchymal stem cells (BMSCs), cardiac fibroblasts (CFBs), cardiomyocytes (CMs). Results: Cardiac TCs projected characteristic telopodes with thin segments (podomers) in alternation with dilation (podoms). In addition, 64% of the primary cultured cardiac TCs were composed of CD117+CD34+ cardiac TCs; which was verified by immunofluorescence. In a live cell imaging system, CD117+CD34+ cardiac TCs were observed to enter into cell division in a short time, followed by an significant invagination forming across the middle of the cell body. Using a real-time quantitative telomeric-repeat amplification assay, the telomerase concentration in CD117+CD34+ cardiac TCs was obviously lower than in BMSCs and CFBs, and significantly higher than in CMs. Conclusions: Cardiac TCs represent a unique cell population and CD117+CD34+ cardiac TCs have relative low telomerase activity that differs from BMSCs, CFBs and CMs and thus they might play an important role in maintaining cardiac homeostasis. PMID:26168836
1. Case Report: Penetrating Cardiac Injury
Directory of Open Access Journals (Sweden)
2013-10-01
Full Text Available Summary: Penetrating cardiac injurys caused by gunshots and penetrating tools have high mortality rates. The way of injury, how the cardiac area is effected and the presence of cardiac tamponadecauses mortality in different rates. However the better treatment quality of hospitals, increasingoperative techniques, and internel care unit quality has not been change during the years. Searching the literature, we want to present a 42 years old male patient whowas injured by knife and had a 1 cm skin wound on chest with cardiac tamponade. After sternotomy a 7 cm laseration was observed in heart. Cardioraphy was performed.
2. PHAEOHYPHOMYCOSIS: CUTANEOUS, SUBCUTANEOUS, NASOPHARYNGEAL LESIONS
Directory of Open Access Journals (Sweden)
1999-06-01
Full Text Available Phaeohyphomycosis is an amalgam of clinical diseases caused by a wide variety of dematiaceous fungi. We are reporting on a 16 year-old patient from Amol with subcutaneous cervical nodes and nasopharyngeal lesions of phaeohypho"nmycosis that were confirmed by pathological examination, direct smear, and culture. After treatment with an oral triazole (Itraconazole for 4 months, all nodes and lesions disappeared and treatment was stopped A new lesion appeared on his chest wall 8 months, therapy with itraconazole was restarted and commuted for a long time.
3. Nerve lesioning with direct current
Science.gov (United States)
Ravid, E. Natalie; Shi Gan, Liu; Todd, Kathryn; Prochazka, Arthur
2011-02-01
Spastic hypertonus (muscle over-activity due to exaggerated stretch reflexes) often develops in people with stroke, cerebral palsy, multiple sclerosis and spinal cord injury. Lesioning of nerves, e.g. with phenol or botulinum toxin is widely performed to reduce spastic hypertonus. We have explored the use of direct electrical current (DC) to lesion peripheral nerves. In a series of animal experiments, DC reduced muscle force by controlled amounts and the reduction could last several months. We conclude that in some cases controlled DC lesioning may provide an effective alternative to the less controllable molecular treatments available today.
4. Interplay between cardiac function and heart development.
Science.gov (United States)
2016-07-01
Mechanotransduction refers to the conversion of mechanical forces into biochemical or electrical signals that initiate structural and functional remodeling in cells and tissues. The heart is a kinetic organ whose form changes considerably during development and disease. This requires cardiomyocytes to be mechanically durable and able to mount coordinated responses to a variety of environmental signals on different time scales, including cardiac pressure loading and electrical and hemodynamic forces. During physiological growth, myocytes, endocardial and epicardial cells have to adaptively remodel to these mechanical forces. Here we review some of the recent advances in the understanding of how mechanical forces influence cardiac development, with a focus on fluid flow forces. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel.
5. Electrocautery for Precancerous Anal Lesions
Science.gov (United States)
Results from a randomized clinical trial conducted in Amsterdam suggest that electrocautery is better than topical imiquimod or fluorouracil at treating potentially precancerous anal lesions in HIV-positive men who have sex with men.
6. Traumatic lesions of pulmonary parenchyma
International Nuclear Information System (INIS)
Five cases of post-traumatic pulmonary lesions (contusion, laceration and hematoma) are presented. The pathophysiology, radiological aspects and differential diagnosis are reviewed. The benign evolution showing the absorption in short time, without medical interference is emphasized. (Author)
International Nuclear Information System (INIS)
Heart structures have traditionally been considered radioresistant. In fact all tissues subjected to radiotherapy can develop lesions. Possible damage includes: - pericardiac fibrosis, the commonest and best individualized, associated with a constriction this leads to a stoppage pattern usually occurring late, around the 18th month. Its frequency depends directly on the total radiation dose; - fibrous myocarditis by direct damage to the heart muscle; - stenosis type lesions of the large coronary trunks; - in exceptional cases lesions of the aorta: hyperplastic degenerescence of the intima and adventitia or of the aortic sigmoid valvules and the mitral valves. Three observations are reported, concerning a coronary, a pericardiac and a coronary, myocardiac and pericardiac lesion. Following this account the irradiation techniques and main experimental data are reviewed and the prophylactic and therapeutic consequences to be derived from our observations and those of the literature are examined
8. Cutaneous lesions of the nose
OpenAIRE
Altmeyer Peter; Paech Volker; Thrandorf Christina; Sand Daniel; Sand Michael; Bechara Falk G
2010-01-01
Abstract Skin diseases on the nose are seen in a variety of medical disciplines. Dermatologists, otorhinolaryngologists, general practitioners and general plastic and dermatologic surgeons are regularly consulted regarding cutaneous lesions on the nose. This article is the second part of a review series dealing with cutaneous lesions on the head and face, which are frequently seen in daily practice by a dermatologic surgeon. In this review, we focus on those skin diseases on the nose where su...
9. Rosacea with extensive extrafacial lesions
OpenAIRE
Pereira, TM; Vieira, AP; Sousa-Basto, A.
2008-01-01
Rosacea is a very common skin disorder in the clinical practice that primarily affects the convex areas of the face. Extrafacial rosacea lesions have occasionally been described, but extensive involvement is exceptional. In the absence of its typical clinical or histological features, the diagnosis of extrafacial rosacea may be problematic. We describe an unusual case of rosacea with very exuberant extrafacial lesions, when compared with the limited involvement of the face.
10. Benign Pediatric Salivary Gland Lesions.
Science.gov (United States)
Carlson, Eric R; Ord, Robert A
2016-02-01
Salivary gland lesions are rare in pediatric patients. In addition, the types of salivary gland tumors are different in their distribution in specific sites in the major and minor salivary glands in children compared with adults. This article reviews benign neoplastic and nonneoplastic salivary gland disorders in pediatric patients to help clinicians to develop an orderly differential diagnosis that will lead to expedient treatment of pediatric patients with salivary gland lesions.
11. Apraxia in deep cerebral lesions.
OpenAIRE
Agostoni, E; Coletti, A.; G. Orlando; Tredici, G
1983-01-01
In a series of 50 patients with cerebrovascular lesions (demonstrated with CT scan), seven patients had lesions located in the basal ganglia and/or thalamus. All these seven patients were apractic. Ideomotor apraxia was present in all patients; five also had constructional apraxia, and one had bucco-facial apraxia. None of the patients had utilisation apraxia. These observations indicated that apraxia is not only a "high cerebral (cortical) function", but may depend also on the integrity of s...
12. Downregulation of Rho associated coiled-coil forming protein kinase 1 in the process of delayed myocardialization of cardiac proximal outflow tract septum in connexin 43 knockout mice embryo
Institute of Scientific and Technical Information of China (English)
QI Chun-hua; ZHAO Xiao-qing; MA Duan; MA Xiao-jing; ZHOU Guo-min; HUANG Guo-ying
2011-01-01
Background The connexln43 knockout (Cx43 KO) mouse dies at birth with an enlarged conotruncal region, which leads to the obstruction of the right outflow tract (OFT). Since myocardialization of the proximal OFT septum is one of the key events during heart development, we investigated the process in the Cx43 KO embryo hearts. Rho associated coiled-coil forming protein kinase 1 (ROCK1), is a recently found key molecule to regulate the myocardialization of OFT, but its spatiotemporal expression pattern during myocardialization remains unknown. The objective of this study was to investigate the differentially expressed pattern of ROCK1 between Cx43 KO and wild type embryo hearts, and its relationship with the delayed myocardialization in Cx43 KO embryo hearts.Methods Using immunohistochemistry, the processes of myocardiolization were investigated both in Cx43 KO and wild type embryo hearts. The differentially expressed pattern of ROCK1 between Cx43 KO and wildtype embryo hearts was evaluated both at the mRNA and protein level by real-time RT-PCR and immunohistochemistry.Results The expression of α-sarcomeric actin (α-SCA) in the proximal OFT septum of Cx43 KO embryos was delayed. Meanwhile, it was shown that the downregulation of ROCK1 coincided with delayed myocardialization. The expression of ROCK1 protein was mainly limited to the proximal outflow tract septum from embryo day (E) E11.5 to E15.5. Its expression pattern was similar with that of α-SCA. Real-time RT-PCR found that the expression level of Rock-1 mRNA began at a low level on E11.5 and reached peak at E13.5 and E14.5.Conclusions ROCK1 may have an important role in the process of myocardialization of the proximal OFT septum. Downregulation of ROCK1 is likely to contribute to the aberrant myocardialization in Cx43 KO embryo hearts.
13. Premalignant Lesions in the Kidney
Directory of Open Access Journals (Sweden)
Ziva Kirkali
2001-01-01
Full Text Available Renal cell carcinoma (RCC is the most malignant urologic disease. Different lesions, such as dysplasia in the tubules adjacent to RCC, atypical hyperplasia in the cyst epithelium of von Hippel-Lindau syndrome, and adenoma have been described for a number of years as possible premalignant changes or precursor lesions of RCC. In two recent papers, kidneys adjacent to RCC or removed from other causes were analyzed, and dysplastic lesions were identified and defined in detail. Currently renal intraepithelial neoplasia (RIN is the proposed term for classification. The criteria for a lesion to be defined as premalignant are (1 morphological similarity; (2 spatial association; (3 development of microinvasive carcinoma; (4 higher frequency, severity, and extent then invasive carcinoma; (5 progression to invasive cancer; and (6 similar genetic alterations. RIN resembles the neoplastic cells of RCC. There is spatial association. Progression to invasive carcinoma is described in experimental cancer models, and in some human renal tumors. Similar molecular alterations are found in some putative premalignant changes. The treatment for RCC is radical or partial nephrectomy. Preneoplastic lesions may remain in the renal remnant in patients treated by partial nephrectomy and may be the source of local recurrences. RIN seems to be a biologic precursor of some RCCs and warrants further investigation. Interpretation and reporting of these lesions would reveal important resources for the biological nature and clinical significance. The management of RIN diagnosed in a renal biopsy and partial nephrectomy needs to be answered.
14. Unusual lesions of the mediastinum
Directory of Open Access Journals (Sweden)
Fatima Shamsuddin
2015-01-01
Full Text Available Objectives: To study unusual lesions in the mediastinum, which do not originate from the thymus, lymph nodes, neural tissues or germ cells, and tissues that normally engender pathologic lesions in the mediastinum. Materials and Methods: Of the 65 cases seen, 12 unusual lesion were encountered in a 5½ year period from 2006 to 2011. Results: Two cases of nodular colloid goiter and one each of the mediastinal cyst, undifferentiated carcinoma, and Langerhans cell histiocytosis (LCH affected the anterosuperior mediastinum. In the middle mediastinum, one case each of the mesothelioma, malignant gastrointestinal stromal tumor (GIST, squamous cell carcinoma (SCC, solitary fibrous tumor (SFT, and pleomorphic sarcoma (PS was seen. One case of meningeal melanocytoma (Mme and primary pleural liposarcoma (PL involved the posterior mediastinum. Persistent disease was seen in LCH after 2 years. Of all the cases with malignant lesions, only the patient with SCC was alive after 1 year. Conclusion: The cases of primary and SCC, LCH, melanocytoma, liposarcoma and PS, and GIST are unexpected and very rarely have paradigms in the mediastinum. Radiologic impression and knowledge of the compartment where these lesions arose from hardly assisted in arriving at a definitive opinion as the lesions were not typical of this location. A high index of suspicion and the immunohistochemical profile facilitated the final diagnosis.
15. Simulation of spiculated breast lesions
Science.gov (United States)
Elangovan, Premkumar; Alrehily, Faisal; Pinto, R. Ferrari; Rashidnasab, Alaleh; Dance, David R.; Young, Kenneth C.; Wells, Kevin
2016-03-01
Virtual clinical trials are a promising new approach increasingly used for the evaluation and comparison of breast imaging modalities. A key component in such an assessment paradigm is the use of simulated pathology, in particular, simulation of lesions. Breast mass lesions can be generally classified into two categories based on their appearance; nonspiculated masses and spiculated masses. In our previous work, we have successfully simulated non-spiculated masses using a fractal growth process known as diffusion limited aggregation. In this new work, we have extended the DLA model to simulate spiculated lesions by using features extracted from patient DBT images containing spiculated lesions. The features extracted included spicule length, width, curvature and distribution. This information was used to simulate realistic looking spicules which were attached to the surface of a DLA mass to produce a spiculated mass. A batch of simulated spiculated masses was inserted into normal patient images and presented to an experienced radiologist for review. The study yielded promising results with the radiologist rating 60% of simulated lesions in 2D and 50% of simulated lesions in DBT as realistic.
16. Double-valve Libman-Sacks endocarditis causing ventricular fibrillation cardiac arrest.
Science.gov (United States)
Tanawuttiwat, Tanyanan; Dia, Muhyaldeen; Hanif, Tabassum; Mihailescu, Mihaela
2011-01-01
Libman-Sacks endocarditis is a well-known and rather common cardiac manifestation of systemic lupus erythematosus. Transesophageal and transthoracic echocardiography are the definitive imaging methods used to evaluate cardiac valvular involvement in this disease. Valvular masses (vegetations) and valvular thickening are 2 common morphologic echocardiographic patterns. Libman-Sacks lesions are typically characterized by single-valve involvement and their small size of 1 to 4 mm.Herein, we present the unusual case of a 22-year-old woman with newly diagnosed systemic lupus erythematosus who had large, sterile vegetations of Libman-Sacks endocarditis that involved the mitral and aortic valves. This compromised coronary blood flow and resulted in ventricular fibrillation cardiac arrest. The vegetations were surgically excised, and the patient's cardiac function recovered. We discuss the treatment of the patient and that of Libman-Sacks endocarditis.
17. Collaborative form(s)
DEFF Research Database (Denmark)
Gunn, Wendy
the process of research rather than its object. In its temporal orientation, anthropology by means of design moves, ‘…forward with people in tandem with their desires and aspirations rather than going back over times passed’ (ibid 2013: 141). Doing design by means of anthropology takes as its most fundamental......Gunn asks us to consider beauty as collaborative forms of action generated by moving between design by means of anthropology and anthropology by means of design. Specifically, she gives focus to play-like reflexions on practices of designing energy products, systems and infrastructure. Design...
18. Cardiac arrest – cardiopulmonary resuscitation
Directory of Open Access Journals (Sweden)
Basri Lenjani
2014-01-01
Conclusions: All survivors from cardiac arrest have received appropriate medical assistance within 10 min from attack, which implies that if cardiac arrest occurs near an institution health care (with an opportunity to provide the emergent health care the rate of survival is higher.
Science.gov (United States)
Rao, Christopher; Patel, Vanash; Ibrahim, Michael; Ahmed, Kamran; Wong, Kathie A; Darzi, Ara; von Segesser, Ludwig K; Athanasiou, Thanos
2011-06-01
Despite the efficacy of cardiac surgery, less invasive interventions with more uncertain long-term outcomes are increasingly challenging surgery as first-line treatment for several congenital, degenerative and ischemic cardiac diseases. The specialty must evolve if it is to ensure its future relevance. More importantly, it must evolve to ensure that future patients have access to treatments with proven long-term effectiveness. This cannot be achieved without dynamic leadership; however, our contention is that this is not enough. The demands of a modern surgical career and the importance of the task at hand are such that the serendipitous emergence of traditional charismatic leadership cannot be relied upon to deliver necessary change. We advocate systematic analysis and strategic leadership at a local, national and international level in four key areas: Clinical Care, Research, Education and Training, and Stakeholder Engagement. While we anticipate that exceptional individuals will continue to shape the future of our specialty, the creation of robust structures to deliver collective leadership in these key areas is of paramount importance. PMID:20884217
20. Ictal Cardiac Ryhthym Abnormalities.
Science.gov (United States)
Ali, Rushna
2016-01-01
Cardiac rhythm abnormalities in the context of epilepsy are a well-known phenomenon. However, they are under-recognized and often missed. The pathophysiology of these events is unclear. Bradycardia and asystole are preceded by seizure onset suggesting ictal propagation into the cortex impacting cardiac autonomic function, and the insula and amygdala being possible culprits. Sudden unexpected death in epilepsy (SUDEP) refers to the unanticipated death of a patient with epilepsy not related to status epilepticus, trauma, drowning, or suicide. Frequent refractory generalized tonic-clonic seizures, anti-epileptic polytherapy, and prolonged duration of epilepsy are some of the commonly identified risk factors for SUDEP. However, the most consistent risk factor out of these is an increased frequency of generalized tonic-clonic seizures (GTC). Prevention of SUDEP is extremely important in patients with chronic, generalized epilepsy. Since increased frequency of GTCS is the most consistently reported risk factor for SUDEP, effective seizure control is the most important preventive strategy. PMID:27347227
1. Pneumothorax in cardiac pacing
DEFF Research Database (Denmark)
Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard;
2012-01-01
AIM: To identify risk factors for pneumothorax treated with a chest tube after cardiac pacing device implantation in a population-based cohort.METHODS AND RESULTS: A nationwide cohort study was performed based on data on 28 860 patients from the Danish Pacemaker Register, which included all Danish...... patients who received their first pacemaker (PM) or cardiac resynchronization device from 1997 to 2008. Multiple logistic regression was used to estimate adjusted odds ratios (aOR) with 95% confidence intervals for the association between risk factors and pneumothorax treated with a chest tube. The median...... age was 77 years (25th and 75th percentile: 69-84) and 55% were male (n = 15 785). A total of 190 patients (0.66%) were treated for pneumothorax, which was more often in women [aOR 1.9 (1.4-2.6)], and in patients with age >80 years [aOR 1.4 (1.0-1.9)], a prior history of chronic obstructive pulmonary...
2. Long-term outcomes following drug-eluting stent implantation in unprotected left main bifurcation lesions
Institute of Scientific and Technical Information of China (English)
GE Lei; Nicola Corvaja; Antonio Colombo; GE Jun-bo; John Cosgrave; Ioannis Iakovou; QIAN Ju-ying; Pierfrancesco Agostoni; Giuseppe M. Sangiorgi; Flavio Airoldi; Iassen Michev; Alaide Chieffo
2007-01-01
Background The safety and efficacy of drug-eluting stents (DES) implantation in unprotected left main (LM)bifurcation lesions has yet to be determined. The aim of the present report was to evaluate the long-term outcome following implantation of DES in unprotected LM bifurcation lesions.Methods We identified 70 consecutive patients treated with DES in unprotected LM bifurcation lesions from April 2003to January 2005. Of them, 42 patients were treated with sirolimus-eluting stent (SES) and 28 patients were treated with paclitaxel-eluting stent (PES).Results Stents to the left anterior descending and to the circumflex were implanted in 62 patients. During 1-year follow-up, 3 (4.3%) patients died of cardiac causes. One of them had myocardial infarction and adjudicated as possibly due to stent thrombosis. Angiographic follow-up was available in 80% of patients. The per lesion restenosis rate was 13.4% in the entire cohort, of which 10.7% occurred in lesions treated with SES and 16.1% in those treated with PES (P=0.58). All restenosis was focal and occurred in the lesions treated with a stent with stent size to post-procedural reference vessel diameter ratio ＜1.0 (17.6% vs 0, P=0.04). The per patient target lesion revascularization rate at 1 year was 17.1%. One year survival free from major adverse cardiac events was 77.1%.Conclusions Treatment of LM bifurcation lesions using DES is a safe and feasible way with a low one-year mortality.The need for revascularization in 17% of patients demands for improvement.
3. Ulcerated lesion of the alveolar ridge.
Science.gov (United States)
Bokmeyer, T J
1980-10-01
Histoplasmosis is a generalized fungal infection that is caused by the organism H capsulatum. In the most common disease-producing mechanism, the organism is inhaled and lodges in the lung, where it initiates an inflammatory focus. The peribronchial lymph nodes are subsequently involved, forming a primary complex that may ultimately calcify and become radiographically evident. From the primary complex, dissemination by the bloodstream may lead to colonization elsewhere. In the less frequent disease-producing complex, the organism is introduced directly into the tissue through a break in its continuity. A primary complex is then formed by involvement of the lymph nodes. Dissemination from such a focus is rare. It is generally believed that oral and pharyngeal lesions of the histoplasmosis represent symptoms of a systemic disease and are not a localized form of the disease. Histoplasmosis can occur at all ages; however, it is more often found in infancy and old age, especially in white males. Any area in the oral cavity may be affected; the most common sites are: larynx, tongue, palate, buccal mucosa. gingiva, and pharynx. The most frequently reported symptoms are pain, hoarseness, loss of weight, ulcer, and sore throat. The appearance of the oral and pharyngeal lesions may vary and may manifest as ulcers, nodules, or verrucous plaques. Deep, indurated ulcers are common, accounting for the predominant clinical impression of squamous carcinoma. PMID:6934220
4. Affect intensity and cardiac arousal.
Science.gov (United States)
Blascovich, J; Brennan, K; Tomaka, J; Kelsey, R M; Hughes, P; Coad, M L; Adlin, R
1992-07-01
Relationships between affect intensity and basal, evoked, and perceived cardiac arousal were investigated in 3 experiments. Affect intensity was assessed using Larsen and Diener's (1987) Affect Intensity Measure (AIM). Cardiac arousal was evoked with exercise in the 1st study and with mental arithmetic in the 2nd and 3rd. Perceived cardiac arousal was measured under optimal conditions using a standard heartbeat discrimination procedure. Women as a group scored higher on the AIM. Affect intensity was unrelated to basal or evoked cardiac arousal and was negatively related to perceived cardiac arousal in all 3 studies. Data suggest that affect intensity, although unrelated to actual physiological arousal, is negatively related to the accuracy with which individuals perceive their own arousal. Results are discussed within the context of an expanded arousal-regulation model (Blascovich, 1990). PMID:1494983
5. Ventricular Arrhythmias in Apparently Normal Hearts: Who Needs an Implantable Cardiac Defibrillator?
Science.gov (United States)
Tan, Alex Y; Ellenbogen, Kenneth
2016-09-01
Idiopathic ventricular tachycardia is often considered a benign form of ventricular arrhythmia in patients without apparent structural heart disease. However, a subset of patients may develop malignant ventricular arrhythmias and present with syncope and sudden cardiac arrest. Survivors of cardiac arrest are candidates for implantable cardiac defibrillators (ICDs). The indications for ICDs in patients with less than a full-blown cardiac arrest presentation but with electrocardiographically high-risk ectopy features remain uncertain. This article addresses some of the uncertainties and pitfalls in ICD risk stratification in this patient group and explores potential mechanisms for malignant conversion of benign premature ventricular complexes to sustained arrhythmia.
6. Ventricular Arrhythmias in Apparently Normal Hearts: Who Needs an Implantable Cardiac Defibrillator?
Science.gov (United States)
Tan, Alex Y; Ellenbogen, Kenneth
2016-09-01
Idiopathic ventricular tachycardia is often considered a benign form of ventricular arrhythmia in patients without apparent structural heart disease. However, a subset of patients may develop malignant ventricular arrhythmias and present with syncope and sudden cardiac arrest. Survivors of cardiac arrest are candidates for implantable cardiac defibrillators (ICDs). The indications for ICDs in patients with less than a full-blown cardiac arrest presentation but with electrocardiographically high-risk ectopy features remain uncertain. This article addresses some of the uncertainties and pitfalls in ICD risk stratification in this patient group and explores potential mechanisms for malignant conversion of benign premature ventricular complexes to sustained arrhythmia. PMID:27521094
7. Three-dimensional cardiac tissue fabrication based on cell sheet technology.
Science.gov (United States)
Masuda, Shinako; Shimizu, Tatsuya
2016-01-15
Cardiac tissue engineering is a promising therapeutic strategy for severe heart failure. However, conventional tissue engineering methods by seeding cells into biodegradable scaffolds have intrinsic limitations such as inflammatory responses and fibrosis arising from the degradation of scaffolds. On the other hand, we have developed cell sheet engineering as a scaffold-free approach for cardiac tissue engineering. Confluent cultured cells are harvested as an intact cell sheet using a temperature-responsive culture surface. By layering cardiac cell sheets, it is possible to form electrically communicative three-dimensional cardiac constructs. Cell sheet transplantation onto damaged hearts in several animal models has revealed improvements in heart functions. Because of the lack of vasculature, the thickness of viable cardiac cell sheet-layered tissues is limited to three layers. Pre-vascularized structure formation within cardiac tissue and multi-step transplantation methods has enabled the formation of thick vascularized tissues in vivo. Furthermore, development of original bioreactor systems with vascular beds has allowed reconstruction of three-dimensional cardiac tissues with a functional vascular structure in vitro. Large-scale culture systems to generate pluripotent stem cell-derived cardiac cells can create large numbers of cardiac cell sheets. Three-dimensional cardiac tissues fabricated by cell sheet engineering may be applied to treat heart disease and tissue model construction.
8. Genetic and physiologic dissection of the vertebrate cardiac conduction system.
Directory of Open Access Journals (Sweden)
Neil C Chi
2008-05-01
Full Text Available Vertebrate hearts depend on highly specialized cardiomyocytes that form the cardiac conduction system (CCS to coordinate chamber contraction and drive blood efficiently and unidirectionally throughout the organism. Defects in this specialized wiring system can lead to syncope and sudden cardiac death. Thus, a greater understanding of cardiac conduction development may help to prevent these devastating clinical outcomes. Utilizing a cardiac-specific fluorescent calcium indicator zebrafish transgenic line, Tg(cmlc2:gCaMP(s878, that allows for in vivo optical mapping analysis in intact animals, we identified and analyzed four distinct stages of cardiac conduction development that correspond to cellular and anatomical changes of the developing heart. Additionally, we observed that epigenetic factors, such as hemodynamic flow and contraction, regulate the fast conduction network of this specialized electrical system. To identify novel regulators of the CCS, we designed and performed a new, physiology-based, forward genetic screen and identified for the first time, to our knowledge, 17 conduction-specific mutations. Positional cloning of hobgoblin(s634 revealed that tcf2, a homeobox transcription factor gene involved in mature onset diabetes of the young and familial glomerulocystic kidney disease, also regulates conduction between the atrium and the ventricle. The combination of the Tg(cmlc2:gCaMP(s878 line/in vivo optical mapping technique and characterization of cardiac conduction mutants provides a novel multidisciplinary approach to further understand the molecular determinants of the vertebrate CCS.
9. A Common Polymorphism of the Human Cardiac Sodium Channel Alpha Subunit (SCN5A Gene Is Associated with Sudden Cardiac Death in Chronic Ischemic Heart Disease.
Directory of Open Access Journals (Sweden)
Boglárka Marcsa
Full Text Available Cardiac death remains one of the leading causes of mortality worldwide. Recent research has shed light on pathophysiological mechanisms underlying cardiac death, and several genetic variants in novel candidate genes have been identified as risk factors. However, the vast majority of studies performed so far investigated genetic associations with specific forms of cardiac death only (sudden, arrhythmogenic, ischemic etc.. The aim of the present investigation was to find a genetic marker that can be used as a general, powerful predictor of cardiac death risk. To this end, a case-control association study was performed on a heterogeneous cohort of cardiac death victims (n=360 and age-matched controls (n=300. Five single nucleotide polymorphisms (SNPs from five candidate genes (beta2 adrenergic receptor, nitric oxide synthase 1 adaptor protein, ryanodine receptor 2, sodium channel type V alpha subunit and transforming growth factor-beta receptor 2 that had previously been shown to associate with certain forms of cardiac death were genotyped using sequence-specific real-time PCR probes. Logistic regression analysis revealed that the CC genotype of the rs11720524 polymorphism in the SCN5A gene encoding a subunit of the cardiac voltage-gated sodium channel occurred more frequently in the highly heterogeneous cardiac death cohort compared to the control population (p=0.019, odds ratio: 1.351. A detailed subgroup analysis uncovered that this effect was due to an association of this variant with cardiac death in chronic ischemic heart disease (p=0.012, odds ratio = 1.455. None of the other investigated polymorphisms showed association with cardiac death in this context. In conclusion, our results shed light on the role of this non-coding polymorphism in cardiac death in ischemic cardiomyopathy. Functional studies are needed to explore the pathophysiological background of this association.
10. Ouabain, a cardiac glycoside, inhibits the Fanconi anemia/BRCA pathway activated by DNA interstrand cross-linking agents.
Directory of Open Access Journals (Sweden)
Dong Wha Jun
Full Text Available Modulation of the DNA repair pathway is an emerging target for the development of anticancer drugs. DNA interstrand cross-links (ICLs, one of the most severe forms of DNA damage caused by anticancer drugs such as cisplatin and mitomycin C (MMC, activates the Fanconi anemia (FA/BRCA DNA repair pathway. Inhibition of the FA/BRCA pathway can enhance the cytotoxic effects of ICL-inducing anticancer drugs and can reduce anticancer drug resistance. To find FA/BRCA pathway inhibitory small molecules, we established a cell-based high-content screening method for quantitating the activation of the FA/BRCA pathway by measuring FANCD2 foci on DNA lesions and then applied our method to chemical screening. Using commercial LOPAC1280 chemical library screening, ouabain was identified as a competent FA/BRCA pathway inhibitory compound. Ouabain, a member of the cardiac glycoside family, binds to and inhibits Na(+/K(+-ATPase and has been used to treat heart disease for many years. We observed that ouabain, as well as other cardiac glycoside family members--digitoxin and digoxin--down-regulated FANCD2 and FANCI mRNA levels, reduced monoubiquitination of FANCD2, inhibited FANCD2 foci formation on DNA lesions, and abrogated cell cycle arrest induced by MMC treatment. These inhibitory activities of ouabain required p38 MAPK and were independent of cellular Ca(2+ ion increase or the drug uptake-inhibition effect of ouabain. Furthermore, we found that ouabain potentiated the cytotoxic effects of MMC in tumor cells. Taken together, we identified an additional effect of ouabain as a FA/BRCA pathway-inhibiting chemosensitization compound. The results of this study suggest that ouabain may serve as a chemosensitizer to ICL-inducing anticancer drugs.
11. Tomoregulin-1 prevents cardiac hypertrophy after pressure overload in mice by inhibiting TAK1-JNK pathways
Directory of Open Access Journals (Sweden)
Dan Bao
2015-08-01
Full Text Available Cardiac hypertrophy is associated with many forms of heart disease, and identifying important modifier genes involved in the pathogenesis of cardiac hypertrophy could lead to the development of new therapeutic strategies. Tomoregulin-1 is a growth factor that is primarily involved in embryonic development and adult central nervous system (CNS function, and it is expressed abnormally in a variety of CNS pathologies. Tomoregulin-1 is also expressed in the myocardium. However, the effects of tomoregulin-1 on the heart, particularly on cardiac hypertrophy, remains unknown. The aim of the study is to examine whether and by what mechanism tomoregulin-1 regulates the development of cardiac hypertrophy induced by pressure overload. In this study, we found that tomoregulin-1 was significantly upregulated in two cardiac hypertrophy models: cTnTR92Q transgenic mice and thoracic aorta constriction (TAC-induced cardiac hypertrophy mice. The transgenic overexpression of tomoregulin-1 increased the survival rate, improved the cardiac geometry and functional parameters of echocardiography, and decreased the degree of cardiac hypertrophy of the TAC mice, whereas knockdown of tomoregulin-1 expression resulted in an opposite phenotype and exacerbated phenotypes of cardiac hypertrophy induced by TAC. A possible mechanism by which tomoregulin-1 regulates the development of cardiac hypertrophy in TAC-induced cardiac hypertrophy is through inhibiting TGFβ non-canonical (TAK1-JNK pathways in the myocardium. Tomoregulin-1 plays a protective role in the modulation of adverse cardiac remodeling from pressure overload in mice. Tomoregulin-1 could be a therapeutic target to control the development of cardiac hypertrophy.
12. Atrial fibrillation after cardiac surgery
Directory of Open Access Journals (Sweden)
Nair Suresh
2010-01-01
Full Text Available Once considered as nothing more than a nuisance after cardiac surgery, the importance of postoperative atrial fibrillation (POAF has been realized in the last decade, primarily because of the morbidity associated with the condition. Numerous causative factors have been described without any single factor being singled out as the cause of this complication. POAF has been associated with stroke, renal failure and congestive heart failure, although it is difficult to state whether POAF is directly responsible for these complications. Guidelines have been formulated for prevention of POAF. However, very few cardiothoracic centers follow any form of protocol to prevent POAF. Routine use of prophylaxis would subject all patients to the side effects of anti-arrhythmic drugs, while only a minority of the patients do actually develop this problem postoperatively. Withdrawal of beta blockers in the postoperative period has been implicated as one of the major causes of POAF. Amiodarone, calcium channel blockers and a variety of other pharmacological agents have been used for the prevention of POAF. Atrial pacing is a non-pharmacological measure which has gained popularity in the prevention of POAF. There is considerable controversy regarding whether rate control is superior to rhythm control in the treatment of established atrial fibrillation (AF. Amiodarone plays a central role in both rate control and rhythm control in postoperative AF. Newer drugs like dronedarone and ranazoline are likely to come into the market in the coming years.
13. Physics of Cardiac Arrhythmogenesis
Science.gov (United States)
Karma, Alain
2013-04-01
A normal heartbeat is orchestrated by the stable propagation of an excitation wave that produces an orderly contraction. In contrast, wave turbulence in the ventricles, clinically known as ventricular fibrillation (VF), stops the heart from pumping and is lethal without prompt defibrillation. I review experimental, computational, and theoretical studies that have shed light on complex dynamical phenomena linked to the initiation, maintenance, and control of wave turbulence. I first discuss advances made to understand the precursor state to a reentrant arrhythmia where the refractory period of cardiac tissue becomes spatiotemporally disordered; this is known as an arrhythmogenic tissue substrate. I describe observed patterns of transmembrane voltage and intracellular calcium signaling that can contribute to this substrate, and symmetry breaking instabilities to explain their formation. I then survey mechanisms of wave turbulence and discuss novel methods that exploit electrical pacing stimuli to control precursor patterns and low-energy pulsed electric fields to control turbulence.
14. Mediastinitis after cardiac transplantation
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Noedir A. G. Stolf
2000-05-01
Full Text Available OBJECTIVE: Assessment of incidence and behavior of mediastinitis after cardiac transplantation. METHODS: From 1985 to 1999, 214 cardiac transplantations were performed, 12 (5.6% of the transplanted patients developed confirmed mediastinitis. Patient's ages ranged from 42 to 66 years (mean of 52.3±10.0 years and 10 (83.3% patients were males. Seven (58.3% patients showed sternal stability on palpation, 4 (33.3% patients had pleural empyema, and 2 (16.7% patients did not show purulent secretion draining through the wound. RESULTS: Staphylococcus aureus was the infectious agent identified in the wound secretion or in the mediastinum, or both, in 8 (66.7% patients. Staphylococcus epidermidis was identified in 2 (16.7% patients, Enterococcus faecalis in 1 (8.3% patient, and the cause of mediastinitis could not be determined in 1 (8.3% patient. Surgical treatment was performed on an emergency basis, and the extension of the débridement varied with local conditions. In 2 (16.7% patients, we chose to leave the surgical wound open and performed daily dressings with granulated sugar. Total sternal resection was performed in only 1 (8.3% patient. Out of this series, 5 (41.7% patients died, and the causes of death were related to the infection. Autopsy revealed persistence of mediastinitis in 1 (8.3% patient. CONCLUSION: Promptness in diagnosing mediastinitis and precocious surgical drainage have changed the natural evolution of this disease. Nevertheless, observance of the basic precepts of prophylaxis of infection is still the best way to treat mediastinitis.
15. Platelets and cardiac arrhythmia
Directory of Open Access Journals (Sweden)
Jonas S De Jong
2010-12-01
Full Text Available Sudden cardiac death remains one of the most prevalent modes of death in industrialized countries, and myocardial ischemia due to thrombotic coronary occlusion is its primary cause. The role of platelets in the occurrence of SCD extends beyond coronary flow impairment by clot formation. Here we review the substances released by platelets during clot formation and their arrhythmic properties. Platelet products are released from three types of platelet granules: dense core granules, alpha-granules, and platelet lysosomes. The physiologic properties of dense granule products are of special interest as a potential source of arrhythmic substances. They are released readily upon activation and contain high concentrations of serotonin, histamine, purines, pyrimidines, and ions such as calcium and magnesium. Potential arrhythmic mechanisms of these substances, e.g. serotonin and high energy phosphates, include induction of coronary constriction, calcium overloading, and induction of delayed after-depolarizations. Alpha-granules produce thromboxanes and other arachidonic acid products with many potential arrhythmic effects mediated by interference with cardiac sodium, calcium and potassium channels. Alpha-granules also contain hundreds of proteins that could potentially serve as ligands to receptors on cardiomyocytes. Lysosomal products probably do not have an important arrhythmic effect. Platelet products and ischemia can induce coronary permeability, thereby enhancing interaction with surrounding cardiomyocytes. Antiplatelet therapy is known to improve survival after myocardial infarction. Although an important part of this effect results from prevention of coronary clot formation, there is evidence to suggest that antiplatelet therapy also induces anti-arrhythmic effects during ischemia by preventing the release of platelet activation products.
16. Metoclopramide-induced cardiac arrest
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Martha M. Rumore
2011-11-01
Full Text Available The authors report a case of cardiac arrest in a patient receiving intravenous (IV metoclopramide and review the pertinent literature. A 62-year-old morbidly obese female admitted for a gastric sleeve procedure, developed cardiac arrest within one minute of receiving metoclopramide 10 mg via slow intravenous (IV injection. Bradycardia at 4 beats/min immediately appeared, progressing rapidly to asystole. Chest compressions restored vital function. Electrocardiogram (ECG revealed ST depression indicative of myocardial injury. Following intubation, the patient was transferred to the intensive care unit. Various cardiac dysrrhythmias including supraventricular tachycardia (SVT associated with hypertension and atrial fibrillation occurred. Following IV esmolol and metoprolol, the patient reverted to normal sinus rhythm. Repeat ECGs revealed ST depression resolution without pre-admission changes. Metoclopramide is a non-specific dopamine receptor antagonist. Seven cases of cardiac arrest and one of sinus arrest with metoclopramide were found in the literature. The metoclopramide prescribing information does not list precautions or adverse drug reactions (ADRs related to cardiac arrest. The reaction is not dose related but may relate to the IV administration route. Coronary artery disease was the sole risk factor identified. According to Naranjo, the association was possible. Other reports of cardiac arrest, severe bradycardia, and SVT were reviewed. In one case, five separate IV doses of 10 mg metoclopramide were immediately followed by asystole repeatedly. The mechanism(s underlying metoclopramide’s cardiac arrest-inducing effects is unknown. Structural similarities to procainamide may play a role. In view of eight previous cases of cardiac arrest from metoclopramide having been reported, further elucidation of this ADR and patient monitoring is needed. Our report should alert clinicians to monitor patients and remain diligent in surveillance and
17. Focal parenchymal lesions in community-acquired bacterial meningitis in adults: a clinico-radiological study
Energy Technology Data Exchange (ETDEWEB)
Katchanov, Juri [Campus Charite Mitte, Charite, Department of Neurology, Berlin (Germany); University Hospital Charite, Campus Benjamin Franklin, Department of Neurology, Berlin (Germany); Siebert, Eberhard; Klingebiel, Randolf [Campus Charite Mitte, Charite, Department of Neuroradiology, Berlin (Germany); Endres, Matthias [Campus Charite Mitte, Charite, Department of Neurology, Berlin (Germany); Charite-Universitaetsmedizin Berlin, Center for Stroke Research Berlin, Berlin (Germany)
2009-11-15
Here, we analyzed the frequency, morphological pattern, and imaging characteristics of focal lesions as a consequence of community-acquired bacterial meningitis. We hypothesized that diffusion-weighted imaging combined with contrast-enhanced imaging, serial scanning, and multimodal vascular studies would provide further insight into the pathological basis of such parenchymal lesions in bacterial meningitis. We reviewed clinical and imaging data (i.e., magnetic resonance tomography, magnetic resonance angiography, computed tomography angiography, digital subtraction angiography) of 68 adult patients admitted to our neurological intensive care unit between March 1998 and February 2009 with the diagnosis of community-acquired bacterial meningitis. We identified seven patients with parenchymal lesions. These lesions could be attributed to four morphological patterns: (1) territorial cerebral ischemia, (2) perforating vessels ischemia, (3) ischemia of presumed cardiac origin, and (4) isolated cortical lesions. Whereas the patterns (1) and (2) were associated with vasculopathy of large- and medium-sized vessels (as shown by cerebral vascular imaging), vessel imaging in (3) and (4) did not show abnormal findings. Our study implies that parenchymal lesions in acute bacterial meningitis are mainly ischemic and due to involvement of large-, medium-, and small-sized arteries of the brain. Diffusion-weighted imaging combined with conventional, CT-, or MR-based cerebral angiography revealed the underlying pathophysiological mechanisms in the majority of patients. Furthermore, we detected two patients with isolated bilateral cortical involvement and normal vessel imaging. These lesions might represent ischemia due to the involvement of small pial and intracortical arteries. (orig.)
18. Renal lesions of nondomestic felids.
Science.gov (United States)
Newkirk, K M; Newman, S J; White, L A; Rohrbach, B W; Ramsay, E C
2011-05-01
To comprehensively evaluate the occurrence of renal lesions in a variety of nondomestic felids, necropsy cases from 1978 to 2008 were reviewed from a municipal zoo and a large cat sanctuary for those in which the kidneys were examined histologically. Seventy exotic felids were identified (25 tigers, 18 lions, 6 cougars, 5 leopards, 3 snow leopards, 3 clouded leopards, 3 Canadian lynx, 2 ocelots, 2 bobcats, 2 cheetahs, 1 jaguar), and their histologic renal lesions were evaluated and compared. The most common lesion was tubulointerstitial nephritis (TIN); 36 of 70 (51%) cats were affected to some degree. Lymphocytic interstitial nephritis was the most common lesion in the tigers (9 of 25, 36%) and was rarely seen in other species. Although the renal pelvis was not available for all cats, 28 of 47 (60%) had some degree of lymphocytic pyelitis. There was no significant association between the presence of pyelitis and that of TIN. Only 1 cat had pyelonephritis. Renal papillary necrosis was present in 13 of 70 (19%) cats and was significantly associated with historical nonsteroidal anti-inflammatory drug treatment (odds ratio, 7.1; 95% confidence interval, 1.9 to 26.8). Only 1 cat (lion) had amyloid accumulation, and it was restricted to the corticomedullary junction. Primary glomerular lesions were absent in all cats. Intraepithelial pigment was identified in many of the cats but was not correlated with severity of TIN. Despite several previous reports describing primary glomerular disease or renal amyloidosis in exotic felids, these lesions were rare to absent in this population. PMID:20876911
19. Epigenetic regulation in cardiac fibrosis
Institute of Scientific and Technical Information of China (English)
Li-Ming; Yu; Yong; Xu
2015-01-01
Cardiac fibrosis represents an adoptive response in the heart exposed to various stress cues. While resolution of the fibrogenic response heralds normalization of heart function, persistent fibrogenesis is usually associated with progressive loss of heart function and eventually heart failure. Cardiac fibrosis is regulated by a myriad of factors that converge on the transcription of genes encoding extracellular matrix proteins, a process the epigenetic machinery plays a pivotal role. In this minireview, we summarize recent advances regarding the epigenetic regulation of cardiac fibrosis focusing on the role of histone and DNA modifications and non-coding RNAs.
20. Music Therapy for Post Operative Cardiac Patients
DEFF Research Database (Denmark)
Schou, Karin
Background This study is the first controlled research study undertaken in the early phase of rehabilitation after cardiac surgery investigating the effect of a receptive music therapy method. Various forms of music therapy interventions including both active and receptive methods were reported...... to be significantly more effective than music treatment with music medicine. Music listening and receptive music therapy (such as Guided Imagery and Music) have been proposed to help patients both before heart surgery and during the recovery phase. This study therefore intended to explore both a music therapy...
1. Cardiac perioperative complications in noncardiac surgery
OpenAIRE
2008-01-01
Anesthesiologists are confronted with an increasing population of patients undergoing noncardiac surgery who are at risk for cardiac complications in the perioperative period. Perioperative cardiac complications are responsible for significant mortality and morbidity. The aim of the present study was to determine the incidence of perioperative (operative and postoperative) cardiac complications and correlations between the incidence of perioperative cardiac complications and type of surgical ...
2. Lesions of juxtacortical origin (surface lesions of bone)
Energy Technology Data Exchange (ETDEWEB)
Kenan, S. (Dept. of Orthopaedics, Mount Sinai School of Medicine, New York, NY (United States)); Abdelwahab, I.F. (Dept. of Radiology, Mount Sinai School of Medicine, New York, NY (United States)); Klein, M.J. (Dept. of Pathology, Mount Sinai School of Medicine, New York, NY (United States)); Hermann, G. (Dept. of Radiology, Mount Sinai School of Medicine, New York, NY (United States)); Lewis, M.M. (Dept. of Orthopaedics, Mount Sinai School of Medicine, New York, NY (United States))
1993-01-01
A large variety of tumor and tumor-like conditions have been shown to originate from the surface of bone. Most surface lesions are associated with periosteal reaction. The periosteum is a multipotential membrane. Its cellular composition may give rise to a variety of both neoplasms and tumor-like conditions. To avoid misinterpretation, the orthopedist, radiologist, and pathologist should be familiar with the entire spectrum of surface lesions. A better understanding of the natural history and biological behavior at different lesional maturity stages and correlation of the history with the radiographic and pathological findings is essential to establish the correct diagnosis. A history of injury of blunt trauma is very important. A stress fracture may produce a periosteal reaction acd callus that can be difficult to distinguish from osteosarcoma. In this review article, the authors wish to describe and define each term by its anatomy and radiographic features while discussing the entire spectrum of surface lesions. All the illustrative cases in this review article have been proven histologically. (orig.)
3. Detection of Herplex Simplex Virus-1 and -2 in Cardiac Myxomas
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Ioannis S. Pateras
2012-01-01
Full Text Available The etiology of sporadic cardiac myxomas remains elusive. The tendency for these lesions to recur following resection, their immunopathological characteristics, along with their histological and molecular profile, may implicate the presence of an infective agent in this type of tumor. In this study, we investigated the presence of herpes simplex virus (HSV DNA in a cohort of cardiac myxomas in a tertiary referral centre. Twenty-nine formalin-fixed paraffin-embedded (FFPE sporadic cardiac myxomas were obtained, 17 of which were shown to be informative. These were compared to 19 macroscopically and microscopically normal heart tissue specimens. The detection of HSV-1 and -2 genomic sequences was achieved with the use of a combined nested PCR-Restriction Fragment Length Polymorphism methodology. The presence of HSV-1 and/or -2 DNA was demonstrated in 6 of 17 (35% informative sporadic cardiac myxomas, whereas no HSV DNA was detected in normal heart tissues (P<0.01. The existence of HSV-1/2 DNA in sporadic cardiac myxomas, along with its absence from normal heart tissues, reinforces the possibility that HSV infection might be involved in the development of these lesions. Our findings raise the point of anti-HSV medication postsurgically with a potential benefit in reducing the rate of recurrences.
4. Lesion detectability in digital radiography
Science.gov (United States)
Gagne, Robert M.; Boswell, Jonathan S.; Myers, Kyle J.; Peter, Guillaume
2001-06-01
The usefulness of Fourier-based measures of imaging performance has come into question for the evaluation of digital imaging systems. Figures of merit such as detective quantum efficiency are relevant for linear, shift-invariant systems with stationary noise. However, no digital imaging system is shift invariant, and realistic images do not satisfy the stationarity condition. Our methods for task- based evaluation of imaging systems, based on lesion detectability, do not require such assumptions. We have computed the performance of Hotelling and nonprewhitening matched-filter observers for the task of lesion detection in digital radiography.
5. Lesiones frecuentes en atletas profesionales
OpenAIRE
Doyel, Crevecoer
2015-01-01
Durante la práctica del atletismo frecuentemente ocurren lesiones, afectando principalmente a los miembros inferiores. Las causas que las originan son muy diversas y tienen diferentes características de acuerdo al tipo de modalidad realizada dentro del atletismo. Objetivo: Analizar las características de las lesiones más frecuentes en miembros inferiores, en atletas corredores profesionales, de diferentes distancias, de ambos sexos, de entre 18 y 40 años de edad, que practican atletismo en...
6. Flexibilidad y lesiones de futbolistas
OpenAIRE
Gocebate, Verónica
2014-01-01
Cabe destacar que en deporte se requiere de una correcta preparación física y el caso del fútbol no es diferente a cualquier otro. Este es un deporte en equipo que genera un desgaste físico y mental en cada partido en el cual se pueden sufrir diferentes lesiones. Son varios los factores que predisponen a que se produzcan lesiones, por lo que es importante un correcto entrenamiento diario. Objetivo: Determinar la relación entre los niveles de flexibilidad de la cadena muscula...
7. Pediatric Knee Osteochondritis Dissecans Lesions.
Science.gov (United States)
Cruz, Aristides I; Shea, Kevin G; Ganley, Theodore J
2016-10-01
Osteochondritis dissecans (OCD) can cause knee pain and dysfunction in children. The etiology of OCD remains unclear; theories on causes include inflammation, ischemia, ossification abnormalities, genetic factors, and repetitive microtrauma. Most OCD lesions in skeletally immature patients will heal with nonoperative treatment. The success of nonoperative treatment decreases once patients reach skeletal maturity. The goals of surgical treatment include maintenance of articular cartilage congruity, rigid fixation of unstable fragments, and repair of osteochondral defects with cells or tissues that can adequately replace lost or deficient cartilage. Unsalvageable OCD lesions can be treated with various surgical techniques. PMID:27637663
8. Isolated cystic lesion of the callosal genu after traumatic brain injury.
Science.gov (United States)
Kato, Toru; Okumura, Akihisa; Tsuji, Takeshi; Emi, Misugi; Natsume, Jun
2012-06-01
We report the case of a 17-month-old infant who developed an isolated cystic lesion of the callosal genu as a unique lesion of traumatic axonal injury (TAI). Although one of the most common sites of TAI is the corpus callosum, there have been no reports describing the lesion seen in our patient. Brain computed tomography findings were normal on the day of the traffic accident. After 3 months, brain magnetic resonance imaging showed an isolated cystic lesion of the callosal genu that had the appearance of a cystic cavity. This lesion decreased in size 16 months later. The neuroimaging findings of this patient suggest that an isolated cystic lesion of the callosal genu could appear as a unique form of TAI in infants after traumatic brain injury (TBI), but it is nevertheless important to attend to such lesions in children with TBI.
9. Disseminated paracoccidioidomycosis diagnosis based on oral lesions
Directory of Open Access Journals (Sweden)
Liana Preto Webber
2014-01-01
Full Text Available Paracoccidioidomycosis (PCM is a deep mycosis with primary lung manifestations that may present cutaneous and oral lesions. Oral lesions mimic other infectious diseases or even squamous cell carcinoma, clinically and microscopically. Sometimes, the dentist is the first to detect the disease, because lung lesions are asymptomatic, or even misdiagnosed. An unusual case of PCM with 5 months of evolution presenting pulmonary, oral, and cutaneous lesions that was diagnosed by the dentist based on oral lesions is presented and discussed.
10. MR-Based Cardiac and Respiratory Motion-Compensation Techniques for PET-MR Imaging.
Science.gov (United States)
Munoz, Camila; Kolbitsch, Christoph; Reader, Andrew J; Marsden, Paul; Schaeffter, Tobias; Prieto, Claudia
2016-04-01
Cardiac and respiratory motion cause image quality degradation in PET imaging, affecting diagnostic accuracy of the images. Whole-body simultaneous PET-MR scanners allow for using motion information estimated from MR images to correct PET data and produce motion-compensated PET images. This article reviews methods that have been proposed to estimate motion from MR images and different techniques to include this information in PET reconstruction, in order to overcome the problem of cardiac and respiratory motion in PET-MR imaging. MR-based motion correction techniques significantly increase lesion detectability and contrast, and also improve accuracy of uptake values in PET images.
11. Primary Right Atrial Sarcoma Presenting with Cardiac Tamponade and Massive Pleural Effusion
Directory of Open Access Journals (Sweden)
Shahram Momtahen
2016-07-01
Full Text Available Primary cardiac sarcomas are very rare and there is no consensus on management. Clinical presentation is usually late. Despite newer diagnostic technology, prognosis remains dismal. We report a case of right atrial sarcoma in a 28-year-old man who presented with acute cardiac tamponade. Emergency subxiphoid pericardial drainage stabilized the patient's critical condition. The lesion was advanced. Therefore, we only performed a suboptimal surgical resection. Despite planning for radiation, the patient's status deteriorated. Only palliative measures continued during the next four months before his death due to disseminated metastasis and progressive cardiopulmonary failure.
12. Fatal secondary pulmonary hypertension due to cardiac involvement in AIDS-associated Burkitt′s lymphoma
Directory of Open Access Journals (Sweden)
Singh Ashutosh
2006-09-01
Full Text Available Primary cardiac lymphomas are rare lesions in children with acquired immunodeficiency syndrome (AIDS. Most of them are high-grade Burkitt′s or Burkitt-like lymphomas. They usually present with congestive cardiac failure, pericardial effusion or tamponade, arrhythmias, with predominant systemic ′B′ symptoms and often with widespread extranodal involvement. The clinical profile and operative and pathological findings of a 4-year-old boy with AIDS-associated Burkitt′s lymphoma of the heart presenting with acute right heart failure and fatal secondary pulmonary hypertension is reported.
13. Robot-assisted cardiac surgery.
Science.gov (United States)
Ishikawa, Norihiko; Watanabe, Go
2015-01-01
Recognition of the significant advantages of minimizing surgical trauma has resulted in the development of minimally invasive surgical procedures. Endoscopic surgery offers patients the benefits of minimally invasive surgery, and surgical robots have enhanced the ability and precision of surgeons. Consequently, technological advances have facilitated totally endoscopic robotic cardiac surgery, which has allowed surgeons to operate endoscopically rather than through a median sternotomy during cardiac surgery. Thus, repairs for structural heart conditions, including mitral valve plasty, atrial septal defect closure, multivessel minimally invasive direct coronary artery bypass grafting (MIDCAB), and totally endoscopic coronary artery bypass graft surgery (CABG), can be totally endoscopic. Robot-assisted cardiac surgery as minimally invasive cardiac surgery is reviewed. PMID:26134073
14. Recent developments in cardiac pacing.
Science.gov (United States)
Rodak, D J
1995-10-01
Indications for cardiac pacing continue to expand. Pacing to improve functional capacity, which is now common, relies on careful patient selection and technical improvements, such as complex software algorithms and diagnostic capabilities.
15. Robotic Applications in Cardiac Surgery
Directory of Open Access Journals (Sweden)
Alan P. Kypson
2008-11-01
Full Text Available Traditionally, cardiac surgery has been performed through a median sternotomy, which allows the surgeon generous access to the heart and surrounding great vessels. As a paradigm shift in the size and location of incisions occurs in cardiac surgery, new methods have been developed to allow the surgeon the same amount of dexterity and accessibility to the heart in confined spaces and in a less invasive manner. Initially, long instruments without pivot points were used, however, more recent robotic telemanipulation systems have been applied that allow for improved dexterity, enabling the surgeon to perform cardiac surgery from a distance not previously possible. In this rapidly evolving field, we review the recent history and clinical results of using robotics in cardiac surgery.
16. Right inferior longitudinal fasciculus lesions disrupt visual-emotional integration.
Science.gov (United States)
Fischer, David B; Perez, David L; Prasad, Sashank; Rigolo, Laura; O'Donnell, Lauren; Acar, Diler; Meadows, Mary-Ellen; Baslet, Gaston; Boes, Aaron D; Golby, Alexandra J; Dworetzky, Barbara A
2016-06-01
The mechanism by which the brain integrates visual and emotional information remains incompletely understood, and can be studied through focal lesions that selectively disrupt this process. To date, three reported cases of visual hypoemotionality, a vision-specific form of derealization, have resulted from lesions of the temporo-occipital junction. We present a fourth case of this rare phenomenon, and investigate the role of the inferior longitudinal fasciculus (ILF) in the underlying pathophysiology. A 50-year-old right-handed male was found to have a right medial temporal lobe tumor following new-onset seizures. Interstitial laser ablation of the lesion was complicated by a right temporo-parieto-occipital intraparenchymal hemorrhage. The patient subsequently experienced emotional estrangement from visual stimuli. A lesion overlap analysis was conducted to assess involvement of the ILF by this patient's lesion and those of the three previously described cases, and diffusion tensor imaging was acquired in our case to further investigate ILF disruption. All four lesions specifically overlapped with the expected trajectory of the right ILF, and diminished structural integrity of the right ILF was observed in our case. These findings implicate the ILF in visual hypoemotionality, suggesting that the ILF is critical for integrating visual information with its emotional content. PMID:26940563
17. Estrogen Stimulates Homing of Endothelial Progenitor Cells to Endometriotic Lesions.
Science.gov (United States)
Rudzitis-Auth, Jeannette; Nenicu, Anca; Nickels, Ruth M; Menger, Michael D; Laschke, Matthias W
2016-08-01
The incorporation of endothelial progenitor cells (EPCs) into microvessels contributes to the vascularization of endometriotic lesions. Herein, we analyzed whether this vasculogenic process is regulated by estrogen. Estrogen- and vehicle-treated human EPCs were analyzed for migration and tube formation. Endometriotic lesions were induced in irradiated FVB/N mice, which were reconstituted with bone marrow from FVB/N-TgN (Tie2/green fluorescent protein) 287 Sato mice. The animals were treated with 100 μg/kg β-estradiol 17-valerate or vehicle (control) over 7 and 28 days. Lesion growth, cyst formation, homing of green fluorescent protein(+)/Tie2(+) EPCs, vascularization, cell proliferation, and apoptosis were analyzed by high-resolution ultrasonography, caliper measurements, histology, and immunohistochemistry. Numbers of blood circulating EPCs were assessed by flow cytometry. In vitro, estrogen-treated EPCs exhibited a higher migratory and tube-forming capacity when compared with controls. In vivo, numbers of circulating EPCs were not affected by estrogen. However, estrogen significantly increased the number of EPCs incorporated into the lesions' microvasculature, resulting in an improved early vascularization. Estrogen further stimulated the growth of lesions, which exhibited massively dilated glands with a flattened layer of stroma. This was mainly because of an increased glandular secretory activity, whereas cell proliferation and apoptosis were not markedly affected. These findings indicate that vasculogenesis in endometriotic lesions is dependent on estrogen, which adds a novel hormonally regulated mechanism to the complex pathophysiology of endometriosis. PMID:27315780
18. The Relation of Endodontic-Periodontal Lesion and Therapy
Directory of Open Access Journals (Sweden)
Trijani Suwandi
2013-07-01
Full Text Available The correlation between endodontic-periodontal lesion has been documented well be researches. Endodontic lesion originates from pulp, while periodontal lesion originates from periodontal tissues. Anatomically they are connected by apical foramen, lateral canal and accessories, as well as dentin tubules. The correlation appeared as the endodontic defect can be from periodontal lesion, or a periodontal defect is from a pulp tissue. Together they can emerge and form a combination lesion. Endodontic infections have been highly correlated with deeper periodontal pockets and furcation involvement in mandibular, the causal relationship between the two pathoses has not yet been established. This consensus supports the influence of degenerated or inflamed pulp that can happen on the periodontium; but not all researchers agree about the effect of periodontal disease on the pulp. Conclusion: The mechanism of endo-perio lesion need to taken care in order to have appropriate diagnostic so that the right therapy would be able to keep the teeth in the oral cavity.
19. Cystic Lesions in Autoimmune Pancreatitis
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Macarena Gompertz
2015-11-01
Full Text Available Autoimmune pancreatitis (AIP can be chronic or recurrent, but frequently completely reversible after steroid treatment. A cystic lesion in AIP is a rare finding, and it can mimic a pancreatic cystic neoplasm. Difficulties in an exact diagnosis interfere with treatment, and surgery cannot be avoided in some cases. We report the history of a 63-year-old male presenting with jaundice and pruritus. AIP was confirmed by imaging and elevated IgG4 blood levels, and the patient completely recovered after corticosteroid therapy. One year later, he presented with a recurrent episode of AIP with elevated IgG4 levels, accompanied by the appearance of multiple intrapancreatic cystic lesions. All but 1 of these cysts disappeared after steroid treatment, but the remaining cyst in the pancreatic head was even somewhat larger 1 year later. Pancreatoduodenectomy was finally performed. Histology showed the wall of the cystic lesion to be fibrotic; the surrounding pancreatic tissue presented fibrosis, atrophy and lymphoplasmacytic infiltration by IgG4-positive cells, without malignant elements. Our case illustrates the rare possibility that cystic lesions can be part of AIP. These pseudocysts appear in the pancreatic segments involved in the autoimmune disease and can be a consequence of the local inflammation or related to ductal strictures. Steroid treatment should be initiated, after which these cysts can completely disappear with recovery from AIP. Surgical intervention may be necessary in some exceptional cases.
20. Pigmented Lesions of the Vulva
Directory of Open Access Journals (Sweden)
Gürol Açıkgöz
2012-06-01
Full Text Available Pigmented lesions on the vulva are rare and their non specific features cause difficulties in their diagnosis and differential diagnosis. Because of their localization, it is difficult to follow up vulvar lesions, which are generally noticed coincidentally by patients. Vulvar pigmented lesions are classified clinically as macules/papules and patches/plaques to provide ease of the diagnosis. Nevi, angiokeratomas, seborrheic keratosis, melanoma, basal cell carcinoma and squamous cell carcinoma are classified under the macules/papules, and post-inflammatory hyperpigmentation, physiological hyperpigmentation, melanosis and acanthosis nigricans are classified under the patch/plaque. Dermatoscopic examination, which is increasing recently, is very valuable for avoiding possible cosmetic and functional complications of surgical procedures. However, epidermal pigmentations such as vulvar melanosis and vulvar intraepitelyal neoplazi are dermatoscopically indistinguishable. It may also be difficult to diagnose vulvar melanoma clinically and dermatoscopically. Histological examination is the gold standard for the diagnosis of pigmented vulvar lesions, which are clinically and dermatoscopically indistinguishable. (Turk J Dermatol 2012; 6: 39-44
1. CARDIAC RESYNCHRONIZATION THERAPY OF CHRONIC HEART FAILURE AS «BRIDGE» TO CARDIAC TRANSPLANTATION
Directory of Open Access Journals (Sweden)
D. V. Shumakov
2009-01-01
Full Text Available Cardiac transplantation (CTX remains the gold standard for treatment of terminal forms of heart failure. Nevertheless, all over the world shortage of donors and postoperative complications leads to search of alternative therapeutic strategy. Cardiac resynchronization therapy is discussed alternative CTX. Besides, now it is not clear, whether it is possible to prevent CRT CTX in long-term prospect. Thus, we aspired to estimate long-term clinical results in the big group of candidates to CTX which have received CRT-systems in Institute of Transplantation last years. In total 70 patients are operated, from them 5 patients in connection with condition deterioration heart transplantation has been executed. The received experience shows that at patients with left ventricular dissinhroniсity, which are in a waiting list to heart transplantation, application of method CRT may to prevent or delay necessity for heart transplantation, or to become a link as «bridge» to transplantation.
2. Cardiac Biomarkers in Hyperthyroid Cats
OpenAIRE
Sangster, Jodi Kirsten
2013-01-01
Background: Hyperthyroidism has substantial effects on the circulatory system. The cardiac biomarkers NT-proBNP and troponin I (cTNI) have proven useful in identifying cats with myocardial disease but have not been as extensively investigated in hyperthyroidism.Hypothesis: Plasma NT-proBNP and cTNI concentrations are higher in cats with primary cardiac disease than in cats with hyperthyroidism and higher in cats with hyperthyroidism than in healthy control cats.Animals: Twenty-three hyperthyr...
3. Cardiac manifestations in systemic sclerosis
Institute of Scientific and Technical Information of China (English)
Sevdalina; Lambova
2014-01-01
Primary cardiac involvement, which develops as a direct consequence of systemic sclerosis(SSc), may manifest as myocardial damage, fibrosis of the conduction system, pericardial and, less frequently, as valvular disease. In addition, cardiac complications in SSc may develop as a secondary phenomenon due to pulmonary arterial hypertension and kidney pathology. The prevalence of primary cardiac involvement in SSc is variable and difficult to determine because of the diversity of cardiac manifestations, the presence of subclinical periods, the type of diagnostic tools applied, and the diversity of patient populations. When clinically manifested, cardiac involvement is thought to be an important prognostic factor. Profound microvascular disease is a pathognomonic feature of SSc, as both vasospasm and structural alterations are present. Such alterations are thought to predict macrovascular atherosclerosis over time. There are contradictory reports regarding the prevalence of atherosclerosis in SSc. According to some authors, the prevalence of atherosclerosis of the large epicardial coronary arteries is similar to that of the general population, in contrast with other rheumatic diseases such as rheumatoid arthritis and systemic lupus erythematosus. However, the level of inflammation in SSc is inferior. Thus, the atherosclerotic process may not be as aggressive and not easily detectable in smaller studies. Echocardiography(especially tissue Doppler imaging), single-photon emission computed tomography, magnetic resonance imaging and cardiac computed tomography are sensitive techniques for earlier detection of both structural and functional scleroderma-related cardiac pathologies. Screening for subclinical cardiac involvement via modern, sensitive tools provides an opportunity for early diagnosis and treatment, which is of crucial importance for a positive outcome.
4. Computational Modeling of Cardiac Electromechanics
OpenAIRE
Krishnamoorthi, Shankarjee
2013-01-01
Cardiac arrhythmias are a leading cause of death worldwide. Notably, the electrophysiologiy and microstructural requirements for a fatal ventricular arrhythmia remain incompletely understood, thereby the treatment remains largely empirical. Standard antiarrhythmic drug therapy has failed to reduce, and in some instances has increased, the incidence of Sudden Cardiac Death (SCD). Hence, a more complete understanding of the mechanisms that foment a fatal arrhythmia is needed and computational m...
5. Current trends in cardiac rehabilitation
OpenAIRE
Dafoe, W; Huston, P
1997-01-01
Cardiac rehabilitation can reduce mortality and morbidity for patients with many types of cardiac disease cost-effectively, yet is generally underutilized. Rehabilitation is helpful not only for patients who have had a myocardial infarction but also for those with stable angina or congestive heart failure or those who have undergone myocardial revascularization procedures, a heart transplant or heart valve surgery. The beneficial effects of rehabilitation include a reduction in the rate of de...
6. Physiological and pathological cardiac hypertrophy.
Science.gov (United States)
Shimizu, Ippei; Minamino, Tohru
2016-08-01
The heart must continuously pump blood to supply the body with oxygen and nutrients. To maintain the high energy consumption required by this role, the heart is equipped with multiple complex biological systems that allow adaptation to changes of systemic demand. The processes of growth (hypertrophy), angiogenesis, and metabolic plasticity are critically involved in maintenance of cardiac homeostasis. Cardiac hypertrophy is classified as physiological when it is associated with normal cardiac function or as pathological when associated with cardiac dysfunction. Physiological hypertrophy of the heart occurs in response to normal growth of children or during pregnancy, as well as in athletes. In contrast, pathological hypertrophy is induced by factors such as prolonged and abnormal hemodynamic stress, due to hypertension, myocardial infarction etc. Pathological hypertrophy is associated with fibrosis, capillary rarefaction, increased production of pro-inflammatory cytokines, and cellular dysfunction (impairment of signaling, suppression of autophagy, and abnormal cardiomyocyte/non-cardiomyocyte interactions), as well as undesirable epigenetic changes, with these complex responses leading to maladaptive cardiac remodeling and heart failure. This review describes the key molecules and cellular responses involved in physiological/pathological cardiac hypertrophy. PMID:27262674
7. FGF21 and cardiac physiopathology
Directory of Open Access Journals (Sweden)
Anna ePlanavila
2015-08-01
Full Text Available The heart is not traditionally considered either a target or a site of fibroblast growth factor-21 (FGF21 production. However, recent findings indicate that FGF21 can act as a cardiomyokine; that is, it is produced by cardiac cells at significant levels and acts in an autocrine manner on the heart itself. The heart is sensitive to the effects of FGF21, both systemic and locally generated, owing to the expression in cardiomyocytes of β-Klotho, the key co-receptor known to confer specific responsiveness to FGF21 action. FGF21 has been demonstrated to protect against cardiac hypertrophy, cardiac inflammation, and oxidative stress. FGF21 expression in the heart is induced in response to cardiac insults, such as experimental cardiac hypertrophy and myocardial infarction in rodents, as well as in failing human hearts. Intracellular mechanisms involving PPARα and Sirt1 mediate transcriptional regulation of the FGF21 gene in response to exogenous stimuli. In humans, circulating FGF21 levels are elevated in coronary heart disease and atherosclerosis, and are associated with a higher risk of cardiovascular events in patients with type 2 diabetes. These findings provide new insights into the role of FGF21 in the heart and may offer potential therapeutic strategies for cardiac disease.
8. [Stem cells and cardiac regeneration].
Science.gov (United States)
Perez Millan, Maria Ines; Lorenti, Alicia
2006-01-01
Stem cells are defined by virtue of their functional attributes: absence of tissue specific differentitated markers, capable of proliferation, able to self-maintain the population, able to produce a large number of differentiated, functional progeny, able to regenerate the tissue after injury. Cell therapy is an alternative for the treatment of several diseases, like cardiac diseases (cell cardiomyoplasty). A variety of stem cells could be used for cardiac repair: from cardiac and extracardiac sources. Each cell type has its own profile of advantages, limitations, and practicability issues in specific clinical settings. Differentiation of bone marrow stem cells to cardiomyocyte-like cells have been observed under different culture conditions. The presence of resident cardiac stem cell population capable of differentiation into cardiomyocyte or vascular lineage suggests that these cells could be used for cardiac tissue repair, and represent a great promise for clinical application. Stem cells mobilization by cytokines may also offer a strategy for cardiac regeneration. The use of stem cells (embryonic and adult) may hold the key to replacing cells lost in many devastating diseases. This potential benefit is a major focus for stem cell research.
9. Cardiac Regeneration and Stem Cells.
Science.gov (United States)
Zhang, Yiqiang; Mignone, John; MacLellan, W Robb
2015-10-01
After decades of believing the heart loses the ability to regenerate soon after birth, numerous studies are now reporting that the adult heart may indeed be capable of regeneration, although the magnitude of new cardiac myocyte formation varies greatly. While this debate has energized the field of cardiac regeneration and led to a dramatic increase in our understanding of cardiac growth and repair, it has left much confusion in the field as to the prospects of regenerating the heart. Studies applying modern techniques of genetic lineage tracing and carbon-14 dating have begun to establish limits on the amount of endogenous regeneration after cardiac injury, but the underlying cellular mechanisms of this regeneration remained unclear. These same studies have also revealed an astonishing capacity for cardiac repair early in life that is largely lost with adult differentiation and maturation. Regardless, this renewed focus on cardiac regeneration as a therapeutic goal holds great promise as a novel strategy to address the leading cause of death in the developed world.
10. Cardiac involvement in myotonic dystrophy
DEFF Research Database (Denmark)
Lund, Marie; Diaz, Lars Jorge; Ranthe, Mattis Flyvholm;
2014-01-01
genetic testing for DM1. Information on incident cardiac diseases was obtained from the NPR. We estimated standardized incidence ratios (SIRs) of cardiac disease compared with the background population, overall and according to selected diagnostic subgroups (cardiomyopathy, heart failure, conduction...... disorders, arrhythmias, and device implantation). In the DM cohort, SIR for any cardiac disease was 3.42 [95% confidence interval (CI) 3.01-3.86]; for a cardiac disease belonging to the selected subgroups 6.91 (95% CI: 5.93-8.01) and for other cardiac disease 2.59 (95% CI: 2.03-3.25). For a cardiac disease...... belonging to the selected subgroups, the risk was particularly high in the first year after DM diagnosis [SIR 15.4 (95% CI: 10.9-21.3)] but remained significantly elevated in subsequent years [SIR 6.07 (95% CI: 5.11-7.16]). The risk was higher in young cohort members [e.g. 20-39 years: SIR 18.1 (95% CI: 12...
11. Cardiac imaging. A multimodality approach
Energy Technology Data Exchange (ETDEWEB)
Thelen, Manfred [Johannes Gutenberg University Hospital, Mainz (Germany); Erbel, Raimund [University Hospital Essen (Germany). Dept. of Cardiology; Kreitner, Karl-Friedrich [Johannes Gutenberg University Hospital, Mainz (Germany). Clinic and Polyclinic for Diagnostic and Interventional Radiology; Barkhausen, Joerg (eds.) [University Hospital Schleswig-Holstein, Luebeck (Germany). Dept. of Radiology and Nuclear Medicine
2009-07-01
An excellent atlas on modern diagnostic imaging of the heart Written by an interdisciplinary team of experts, Cardiac Imaging: A Multimodality Approach features an in-depth introduction to all current imaging modalities for the diagnostic assessment of the heart as well as a clinical overview of cardiac diseases and main indications for cardiac imaging. With a particular emphasis on CT and MRI, the first part of the atlas also covers conventional radiography, echocardiography, angiography and nuclear medicine imaging. Leading specialists demonstrate the latest advances in the field, and compare the strengths and weaknesses of each modality. The book's second part features clinical chapters on heart defects, endocarditis, coronary heart disease, cardiomyopathies, myocarditis, cardiac tumors, pericardial diseases, pulmonary vascular diseases, and diseases of the thoracic aorta. The authors address anatomy, pathophysiology, and clinical features, and evaluate the various diagnostic options. Key features: - Highly regarded experts in cardiology and radiology off er image-based teaching of the latest techniques - Readers learn how to decide which modality to use for which indication - Visually highlighted tables and essential points allow for easy navigation through the text - More than 600 outstanding images show up-to-date technology and current imaging protocols Cardiac Imaging: A Multimodality Approach is a must-have desk reference for cardiologists and radiologists in practice, as well as a study guide for residents in both fields. It will also appeal to cardiac surgeons, general practitioners, and medical physicists with a special interest in imaging of the heart. (orig.)
12. Effect of a puzzle on the process of students' learning about cardiac physiology.
Science.gov (United States)
Cardozo, Lais Tono; Miranda, Aline Soares; Moura, Maria José Costa Sampaio; Marcondes, Fernanda Klein
2016-09-01
13. SLAP lesions: a treatment algorithm.
Science.gov (United States)
Brockmeyer, Matthias; Tompkins, Marc; Kohn, Dieter M; Lorbach, Olaf
2016-02-01
Tears of the superior labrum involving the biceps anchor are a common entity, especially in athletes, and may highly impair shoulder function. If conservative treatment fails, successful arthroscopic repair of symptomatic SLAP lesions has been described in the literature particularly for young athletes. However, the results in throwing athletes are less successful with a significant amount of patients who will not regain their pre-injury level of performance. The clinical results of SLAP repairs in middle-aged and older patients are mixed, with worse results and higher revision rates as compared to younger patients. In this population, tenotomy or tenodesis of the biceps tendon is a viable alternative to SLAP repairs in order to improve clinical outcomes. The present article introduces a treatment algorithm for SLAP lesions based upon the recent literature as well as the authors' clinical experience. The type of lesion, age of patient, concomitant lesions, and functional requirements, as well as sport activity level of the patient, need to be considered. Moreover, normal variations and degenerative changes in the SLAP complex have to be distinguished from "true" SLAP lesions in order to improve results and avoid overtreatment. The suggestion for a treatment algorithm includes: type I: conservative treatment or arthroscopic debridement, type II: SLAP repair or biceps tenotomy/tenodesis, type III: resection of the instable bucket-handle tear, type IV: SLAP repair (biceps tenotomy/tenodesis if >50 % of biceps tendon is affected), type V: Bankart repair and SLAP repair, type VI: resection of the flap and SLAP repair, and type VII: refixation of the anterosuperior labrum and SLAP repair.
14. Risk factors and the effect of cardiac resynchronization therapy on cardiac and non-cardiac mortality in MADIT-CRT
DEFF Research Database (Denmark)
Perkiomaki, Juha S; Ruwald, Anne-Christine; Kutyifa, Valentina;
2015-01-01
causes, 108 (63.9%) deemed cardiac, and 61 (36.1%) non-cardiac. In multivariate analysis, increased baseline creatinine was significantly associated with both cardiac and non-cardiac deaths [hazard ratio (HR) 2.97, P ...AIMS: To understand modes of death and factors associated with the risk for cardiac and non-cardiac deaths in patients with cardiac resynchronization therapy with implantable cardioverter-defibrillator (CRT-D) vs. implantable cardioverter-defibrillator (ICD) therapy, which may help clarify...... the action and limitations of cardiac resynchronization therapy (CRT) in relieving myocardial dysfunction. METHODS AND RESULTS: In Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy (MADIT-CRT), during 4 years of follow-up, 169 (9.3%) of 1820 patients died of known...
15. Minimum Information about a Cardiac Electrophysiology Experiment (MICEE)
DEFF Research Database (Denmark)
Quinn, T A; Granite, S; Allessie, M A;
2011-01-01
(MICEE). The ultimate goal is to develop a useful tool for cardiac electrophysiologists which facilitates and improves dissemination of the minimum information necessary for reproduction of cardiac electrophysiology research, allowing for easier comparison and utilisation of findings by others....... It is hoped that this will enhance the integration of individual results into experimental, computational, and conceptual models. In its present form, this draft is intended for assessment and development by the research community. We invite the reader to join this effort, and, if deemed productive, implement...
16. Invasive strategy in patients with resuscitated cardiac arrest and ST elevation myocardial infarction.
Science.gov (United States)
Gorjup, Vojka; Noc, Marko; Radsel, Peter
2014-06-26
Coronary artery disease is the most frequent cause of sudden cardiac death. There is general consensus that immediate coronary angiography with percutaneous coronary intervention (PCI) should be performed in all conscious and unconscious patients with ST-elevation myocardial infarction in post-resuscitation electrocardiogram. In these patients acute coronary thrombotic lesion ("ACS" lesion) suitable for PCI is typically present in more than 90%. PCI in these patients is not only feasible and safe but highly effective and there is evidence of improved survival with good neurological outcome. PCI of the culprit lesion is the primary goal while PCI of stable obstructive lesions may be postponed unless post-resuscitation cardiogenic shock is present.
17. Cardiac output during exercise
DEFF Research Database (Denmark)
Siebenmann, C; Rasmussen, P.; Sørensen, H.;
2015-01-01
Several techniques assessing cardiac output (Q) during exercise are available. The extent to which the measurements obtained from each respective technique compares to one another, however, is unclear. We quantified Q simultaneously using four methods: the Fick method with blood obtained from...... the right atrium (Q(Fick-M)), Innocor (inert gas rebreathing; Q(Inn)), Physioflow (impedance cardiography; Q(Phys)), and Nexfin (pulse contour analysis; Q(Pulse)) in 12 male subjects during incremental cycling exercise to exhaustion in normoxia and hypoxia (FiO2 = 12%). While all four methods reported...... a progressive increase in Q with exercise intensity, the slopes of the Q/oxygen uptake (VO2) relationship differed by up to 50% between methods in both normoxia [4.9 ± 0.3, 3.9 ± 0.2, 6.0 ± 0.4, 4.8 ± 0.2 L/min per L/min (mean ± SE) for Q(Fick-M), Q(Inn), QP hys and Q(Pulse), respectively; P = 0...
18. Petrous apex lesions in the pediatric population
Energy Technology Data Exchange (ETDEWEB)
Radhakrishnan, Rupa [University of Cincinnati College of Medicine, Department of Radiology, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Son, Hwa Jung [University of Cincinnati College of Medicine, Department of Otolaryngology-Head and Neck Surgery, Cincinnati, OH (United States); Koch, Bernadette L. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)
2014-03-15
A variety of abnormal imaging findings of the petrous apex are encountered in children. Many petrous apex lesions are identified incidentally while images of the brain or head and neck are being obtained for indications unrelated to the temporal bone. Differential considerations of petrous apex lesions in children include ''leave me alone'' lesions, infectious or inflammatory lesions, fibro-osseous lesions, neoplasms and neoplasm-like lesions, as well as a few rare miscellaneous conditions. Some lesions are similar to those encountered in adults, and some are unique to children. Langerhans cell histiocytosis (LCH) and primary and metastatic pediatric malignancies such as neuroblastoma, rhabomyosarcoma and Ewing sarcoma are more likely to be encountered in children. Lesions such as petrous apex cholesterol granuloma, cholesteatoma and chondrosarcoma are more common in adults and are rarely a diagnostic consideration in children. We present a comprehensive pictorial review of CT and MRI appearances of pediatric petrous apex lesions. (orig.)
19. Imaging of Chest Wall Lesions in Children
Directory of Open Access Journals (Sweden)
A. Hekmatnia
2008-01-01
Full Text Available Chest wall lesions in childhood include a wide range of pathologies; Benign lesions include lipoma, neurofibroma, lymphangioma, hemangioma, and mesenchymal hamartoma."nMalignant lesions include Neuroblastoma, Rhabdo-myosarcoma, Ewing sarcoma, and Askin tumor."nSystemic diseases such as leukemia, lymphoma, Langerhans cell histiocytosis, and also infections such as tuberculosis, and actinomycosis may also cause chest wall lesions."nThe imaging characteristics of these lesions are re-viewed, but only a minority of the lesions shows diagnostic imaging features, and most of lesions re-quire biopsy and histopathological examination for "ndefinitive diagnosis."nThe role of different modalities is discussed with an emphasis on magnetic resonance imaging for demonstrating lesion morphology and local spread. Computed tomography and neuclear medicine being used mainly to assess remote disease."nIn this lecture, we discuss about imaging of chest wall lesions in children.
20. Sleep Apnea and Nocturnal Cardiac Arrhythmia: A Populational Study
Directory of Open Access Journals (Sweden)
Fatima Dumas Cintra
2014-11-01
Full Text Available Background: The mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea. Objective: To analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample. Methods: Cross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart® system. Results: A total of 767 participants (461 men with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001. After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia. Conclusion: Nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample.
1. High Glucose Causes Human Cardiac Progenitor Cell Dysfunction by Promoting Mitochondrial Fission: Role of a GLUT1 Blocker
Science.gov (United States)
Choi, He Yun; Park, Ji Hye; Jang, Woong Bi; Ji, Seung Taek; Jung, Seok Yun; Kim, Da Yeon; Kang, Songhwa; Kim, Yeon Ju; Yun, Jisoo; Kim, Jae Ho; Baek, Sang Hong; Kwon, Sang-Mo
2016-01-01
Cardiovascular disease is the most common cause of death in diabetic patients. Hyperglycemia is the primary characteristic of diabetes and is associated with many complications. The role of hyperglycemia in the dysfunction of human cardiac progenitor cells that can regenerate damaged cardiac tissue has been investigated, but the exact mechanism underlying this association is not clear. Thus, we examined whether hyperglycemia could regulate mitochondrial dynamics and lead to cardiac progenitor cell dysfunction, and whether blocking glucose uptake could rescue this dysfunction. High glucose in cardiac progenitor cells results in reduced cell viability and decreased expression of cell cycle-related molecules, including CDK2 and cyclin E. A tube formation assay revealed that hyperglycemia led to a significant decrease in the tube-forming ability of cardiac progenitor cells. Fluorescent labeling of cardiac progenitor cell mitochondria revealed that hyperglycemia alters mitochondrial dynamics and increases expression of fission-related proteins, including Fis1 and Drp1. Moreover, we showed that specific blockage of GLUT1 improved cell viability, tube formation, and regulation of mitochondrial dynamics in cardiac progenitor cells. To our knowledge, this study is the first to demonstrate that high glucose leads to cardiac progenitor cell dysfunction through an increase in mitochondrial fission, and that a GLUT1 blocker can rescue cardiac progenitor cell dysfunction and downregulation of mitochondrial fission. Combined therapy with cardiac progenitor cells and a GLUT1 blocker may provide a novel strategy for cardiac progenitor cell therapy in cardiovascular disease patients with diabetes. PMID:27350339
2. Detection of telornerase activity and cytology in diagnosis of cardiac cancer
Institute of Scientific and Technical Information of China (English)
Qiang Wang; Qing Ming Wu; Sheng Bao Li
2000-01-01
AIM To investigate the diagnostic significance of cytology and telomerase activity in the exfoliated cells ofcardia obtained from endoscopic brushing in the cardiac cancer.METHODS The techniques of the qualitative TRAP-silver staining and quantitative TRAP-PCR-ELISAwere employed to detect telomerase activity in the exfoliated cells of cardia obtained from endoscopicbrushing in 72 cases with cardial lesions, cytological diagnosis was made at the same time.RESULTS Telomerase activity with cardiac cancer group (1.521 ± 0. 192) was significantly higher than thatwith cardialitis group (0.065± 0.014). Positive rate of telomerase activity detected in cardiac cancer group(88.89%) was significantly higher than that with cardialitis group (11.11%), the former was significantlyhiger than cytological examination (77.78%). The diagnostic rate of cardiac cancer reached 93.33% iftelomerase activity and cytology were examined at the same time.CONCLUSION Cytology and telomerase activity in the exfoliated cardiac cells may be an effective andsensitive methods in the diagnosis of cardiac cancer. This research can be a basis for the mass screening ofcardiac cancer.
3. Insulin Cannot Induce Adipogenic Differentiation in Primary Cardiac Cultures.
Science.gov (United States)
Parameswaran, Sreejit; Sharma, Rajendra K
2016-09-01
Cardiac tissue contains a heterogeneous population of cardiomyocytes and nonmyocyte population especially fibroblasts. Fibroblast differentiation into adipogenic lineage is important for fat accumulation around the heart which is important in cardiac pathology. The differentiation in fibroblast has been observed both spontaneously and due to increased insulin stimulation. The present study aims to observe the effect of insulin in adipogenic differentiation of cardiac cells present in primary murine cardiomyocyte cultures. Oil Red O (ORO) staining has been used for observing the lipid accumulations formed due to adipogenic differentiation in murine cardiomyocyte cultures. The accumulated lipids were quantified by ORO assay and normalized using protein estimation. The lipid accumulation in cardiac cultures did not increase in presence of insulin. However, addition of other growth factors like insulin-like growth factor 1 and epidermal growth factor promoted adipogenic differentiation even in the presence of insulin and other inhibitory molecules such as vitamins. Lipid accumulation also increased in cells grown in media without insulin after an initial exposure to insulin-containing growth media. The current study adds to the existing knowledge that the insulin by itself cannot induce adipogenic induction in the cardiac cultures. The data have significance in the understanding of cardiovascular health especially in diabetic patients. PMID:27574386
4. Male and female hypertrophic rat cardiac myocyte functional responses to ischemic stress and β-adrenergic challenge are different
OpenAIRE
Bell, James R.; Curl, Claire L.; Harding, Tristan W.; Vila Petroff, Martin; Harrap, Stephen B.; Delbridge, Lea M D
2016-01-01
Background Cardiac hypertrophy is the most potent cardiovascular risk factor after age, and relative mortality risk linked with cardiac hypertrophy is greater in women. Ischemic heart disease is the most common form of cardiovascular pathology for both men and women, yet significant differences in incidence and outcomes exist between the sexes. Cardiac hypertrophy and ischemia are frequently occurring dual pathologies. Whether the cellular (cardiomyocyte) mechanisms underlying myocardial dama...
5. System for the diagnosis and monitoring of coronary artery disease, acute coronary syndromes, cardiomyopathy and other cardiac conditions
Science.gov (United States)
Schlegel, Todd T. (Inventor); Arenare, Brian (Inventor)
2008-01-01
Cardiac electrical data are received from a patient, manipulated to determine various useful aspects of the ECG signal, and displayed and stored in a useful form using a computer. The computer monitor displays various useful information, and in particular graphically displays various permutations of reduced amplitude zones and kurtosis that increase the rapidity and accuracy of cardiac diagnoses. New criteria for reduced amplitude zones are defined that enhance the sensitivity and specificity for detecting cardiac abnormalities.
6. Lethal, potentially lethal lesion model
Energy Technology Data Exchange (ETDEWEB)
Curtis, S.B.
1983-07-01
A theoretical framework to describe the formation of lethal mutations by radiation is presented. Lesions that are repaired (and misrepaired) in each type of experiment described (delayed plating and split dose) are assumed to be the same. In this model the same (potentially lethal) lesions cause both sublethal and potentially lethal damage. Potentially lethal damage is defined as damage which may be modified by alterations in postirradiation conditions. Sublethal damage is cellular damage whose accumulation may lead to lethality. A crucial consideration in the expression of the damage is the kind of medium in which the cells are placed during the repair period. Fresh or growth medium (F-medium) is assumed to cause fixation of damage after about 3 hours, while no fixation (only misrepair) occurs in conditioned medium (C-medium).
7. Cytologic diagnosis of pulmonary lesions.
Science.gov (United States)
Rossi, Esther Diana; Mulè, Antonino; Maggiore, Claudia; Miraglia, Antonella; Lauriola, Libero; Vecchio, Fabio Maria; Fadda, Guido
2004-01-01
The major types of cytologic preparations used in most laboratories to detect the lesions of the lower respiratory tract (LRT) are examined. These methods include sputum, bronchial washing, bronchial brushing, bronchoalveolar lavage (BAL) and fine-needle aspiration biopsy (FNAB). Sputum represents the simplest and most cost-effective sampling method even though fiberoptic bronchoscopy and radiologic guided FNAB are superseding it as the first diagnostic choice in most cases. There are advantages and disadvantages associated with each technique:bronchial brushing and FNABs tend to preserve both the cellular details and their architectural arrangement whereas sputum and bronchial washing often cause a variable degree of cellular degeneration and fragmentation. As a result, most pulmonary lesions may be detected and correctly diagnosed if multiple techniques are used to acquire diagnostic material. CT-guided FNAB represents the most effective method to achieve a correct diagnosis in pulmonary tumors. PMID:15852720
8. Real time assessment of RF cardiac tissue ablation with optical spectroscopy
Energy Technology Data Exchange (ETDEWEB)
Demos, S G; Sharareh, S
2008-03-20
An optical spectroscopy approach is demonstrated allowing for critical parameters during RF ablation of cardiac tissue to be evaluated in real time. The method is based on incorporating in a typical ablation catheter transmitting and receiving fibers that terminate at the tip of the catheter. By analyzing the spectral characteristics of the NIR diffusely reflected light, information is obtained on such parameters as, catheter-tissue proximity, lesion formation, depth of penetration of the lesion, formation of char during the ablation, formation of coagulum around the ablation site, differentiation of ablated from healthy tissue, and recognition of micro-bubble formation in the tissue.
9. A case report of odontogenic myxoma with characteristic multilocular lesion
Energy Technology Data Exchange (ETDEWEB)
Lee, Byung Do; Lee, Wan; Paeng, Jun Young [Department of Oral and Maxillofacial Radiology, School of Dentistry, Wonkwang University, Iksan (Korea, Republic of); Son, Hyun Jin [Department of Pathology, Eulji University School of Medicine, Daejeon (Korea, Republic of)
2009-03-15
Although odontogenic myxoma (OM) has various radiographic appearances, the characteristic features of OM are the multilocular radiolucent lesion, straight bony septa along the margin forming either square or triangular spaces. We present a case of OM in a 25-year old-male patient. Multilocular radiolucent lesion on the left mandible body showed tennis racket appearance. Cone beam computed tomography (CBCT) showed straight bony septa along the margin and cortical perforation. This CBCT features would have significantly contributed to allowing a diagnosis of OM. We think that this case shows characteristic radiographic features of odontogenic myxoma.
10. Post-traumatic cystic lesion following fracture of the radius
International Nuclear Information System (INIS)
Post-traumatic cystic lesions are an uncommon complication of fractures in children. They are benign, asymptomatic, non-expansive and tend to resolve spontaneously. Their cause seems to be the invasion of bone-marrow fat by subperiosteal hematoma, which may be visible on radiographs during fracture consolidation of the newly formed subperiosteal bone. The case we present is of cyst formation following a fracture of the distal radius and we evaluate the role of yellow bone marrow in the pathogenesis of the cyst. Its typical features clear differentiation from other lesions, preventing unnecessary and, possibly, invasive examinations. (orig.)
11. Patch in Cardiac Surgery
Directory of Open Access Journals (Sweden)
2014-06-01
Full Text Available Introduction: Excessive bleeding presents a risk for the patient in cardiovascular surgery. Local haemostatic agents are of great value to reduce bleeding and related complications. TachoSil (Nycomed, Linz, Austria is a sterile, haemostatic agent that consists of an equine collagen patchcoated with human fibrinogen and thrombin. This study evaluated the safety and efficacy of TachoSil compared to conventional technique.Methods: Forty-two patients scheduled for open heart surgeries, were entered to this study from August 2010 to May 2011. After primary haemostatic measures, patients divided in two groups based on surgeon’s judgment. Group A: 20 patients for whom TachoSil was applied and group B: 22 patients that conventional method using Surgicel (13 patients or wait and see method (9 cases, were performed in order to control the bleeding. In group A, 10 patients were male with mean age of 56.95±15.67 years and in group B, 9 cases were male with mean age of 49.95±14.41 years. In case group 70% (14/20 of the surgeries were redo surgeries versus 100% (22/22 in control group.Results: Baseline characteristics were similar in both groups. In TachoSil group 75% of patients required transfusion versus 90.90% in group B (P=0.03.Most transfusions consisted of packed red blood cell; 2±1.13 units in group A versus 3.11±1.44 in group B (P=0.01, however there were no significant differences between two groups regarding the mean total volume of intra and post-operative bleeding. Re-exploration was required in 10% in group A versus 13.63% in group B (P=0.67.Conclusion: TachoSil may act as a superior alternative in different types of cardiac surgery in order to control the bleeding and therefore reducing transfusion requirement.
12. Cardiac output monitoring
Directory of Open Access Journals (Sweden)
Mathews Lailu
2008-01-01
Full Text Available Minimally invasive and non-invasive methods of estimation of cardiac output (CO were developed to overcome the limitations of invasive nature of pulmonary artery catheterization (PAC and direct Fick method used for the measurement of stroke volume (SV. The important minimally invasive techniques available are: oesophageal Doppler monitoring (ODM, the derivative Fick method (using partial carbon dioxide (CO 2 breathing, transpulmonary thermodilution, lithium indicator dilution, pulse contour and pulse power analysis. Impedance cardiography is probably the only non-invasive technique in true sense. It provides information about haemodynamic status without the risk, cost and skill associated with the other invasive or minimally invasive techniques. It is important to understand what is really being measured and what assumptions and calculations have been incorporated with respect to a monitoring device. Understanding the basic principles of the above techniques as well as their advantages and limitations may be useful. In addition, the clinical validation of new techniques is necessary to convince that these new tools provide reliable measurements. In this review the physics behind the working of ODM, partial CO 2 breathing, transpulmonary thermodilution and lithium dilution techniques are dealt with. The physical and the physiological aspects underlying the pulse contour and pulse power analyses, various pulse contour techniques, their development, advantages and limitations are also covered. The principle of thoracic bioimpedance along with computation of CO from changes in thoracic impedance is explained. The purpose of the review is to help us minimize the dogmatic nature of practice favouring one technique or the other.
13. Cystic Lesions in Autoimmune Pancreatitis
OpenAIRE
Gompertz, Macarena; Morales, Claudia; Aldana, Hernán; Castillo, Jaime; Berger, Zoltán
2015-01-01
Autoimmune pancreatitis (AIP) can be chronic or recurrent, but frequently completely reversible after steroid treatment. A cystic lesion in AIP is a rare finding, and it can mimic a pancreatic cystic neoplasm. Difficulties in an exact diagnosis interfere with treatment, and surgery cannot be avoided in some cases. We report the history of a 63-year-old male presenting with jaundice and pruritus. AIP was confirmed by imaging and elevated IgG4 blood levels, and the patient completely recovered ...
14. Symmetrical thalamic lesions in infants.
OpenAIRE
Eicke, M.; Briner, J; Willi, U; Uehlinger, J; Boltshauser, E
1992-01-01
Clinical observations and findings on imaging are reported in six newborns with symmetrical thalamic lesions (STL). In three cases the diagnosis was confirmed by postmortem examination. Characteristic observations in this series and 17 previously reported cases include no evidence of perinatal asphyxia, high incidence of polyhydramnios, absent suck and swallow, absent primitive reflexes, appreciable spasticity at or within days of birth, lack of psychomotor development, and death within days ...
15. Cardiac allograft immune activation: current perspectives
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Chang D
2014-12-01
Full Text Available David Chang, Jon Kobashigawa Cedars-Sinai Heart Institute, Los Angeles, CA, USA Abstract: Heart transplant remains the most durable option for end-stage heart disease. Cardiac allograft immune activation and heart transplant rejection remain among the main complications limiting graft and recipient survival. Mediators of the immune system can cause different forms of rejection post-heart transplant. Types of heart transplant rejection include hyperacute rejection, cellular rejection, antibody-mediated rejection, and chronic rejection. In this review, we will summarize the innate and adaptive immune responses which influence the post-heart transplant recipient. Different forms of rejection and their clinical presentation, detection, and immune monitoring will be discussed. Treatment of heart transplant rejection will be examined. We will discuss potential treatment strategies for preventing rejection post-transplant in immunologically high-risk patients with antibody sensitization. Keywords: heart transplant, innate immunity, adaptive immunity, rejection, immunosuppression
16. Computed tomography of cardiac pseudotumors and neoplasms.
Science.gov (United States)
Anavekar, Nandan S; Bonnichsen, Crystal R; Foley, Thomas A; Morris, Michael F; Martinez, Matthew W; Williamson, Eric E; Glockner, James F; Miller, Dylan V; Breen, Jerome F; Araoz, Philip A
2010-07-01
Important features of cardiac masses can be clearly delineated on cardiac computed tomography (CT) imaging. This modality is useful in identifying the presence of a mass, its relationship with cardiac and extracardiac structures, and the features that distinguish one type of mass from another. A multimodality approach to the evaluation of cardiac tumors is advocated, with the use of echocardiography, CT imaging and magnetic resonance imaging as appropriately indicated. In this article, various cardiac masses are described, including pseudotumors and true cardiac neoplasms, and the CT imaging findings that may be useful in distinguishing these rare entities are presented. PMID:20705174
17. Follicular-patterned thyroid lesions
Directory of Open Access Journals (Sweden)
F. Fulya KÖYBAŞIOĞLU
2009-01-01
Full Text Available Aim: Our aim is to determine the minimal cytopathologic criteria needed to make differential diagnosis in follicular-patterned lesions of the thyroid gland.Materials and Methods: We reviewed 56 fine needle aspiration cytology specimens which were reported as “suspicious for follicular-patterned lesions of thyroid” between years 2001 and 2005 in our hospital and their histological slides. Parameters for cytopathologic assesment are cellularity, colloid formation, multilayered rosette formation, follicular cell rings, monolayered sheets, intact follicles, hyperplastic papillae, hyaline stromal fragments, intranuclear inclusions, nuclear grooves, angulated nuclei, nucleoli, cerebriform nuclei, nuclear size, macrophages, flame cells and Hurthle cells. Statistical analysis was performed using χ2 and Fisher's-exact tests and Kolmogorov-Simirnov test.Results: Four cytopathologic features–cerebriform nuclei, angulated nuclei, nuclear grooves and intranuclear inclusion- were constantly observed in the follicular variant of papillary carcinoma (p< 0.05. Diluted colloid, monolayered sheet, nuclear size, macrophage and nucleoli were frequently seen in nodular hyperplasia (p< 0.05. The nuclear size was the sole differential cytopathologic criteria between follicular adenoma and follicular carcinoma (p<0.05.Conclusion: Detailed cytopathologic examination was found to be important in differentiating follicular variant of papillary carcinoma from nodular hyperplasia. On the other hand, none of the cytopathologic findings were sufficient to distinguish follicular adenoma from follicular carcinoma. Therefore, cytopathologists should report such lesions as “follicular neoplasms”.
International Nuclear Information System (INIS)
19. A vertical approach to cardiac arrhythmias.
Science.gov (United States)
Vaughan Williams, E M
1987-10-01
Study of cardiac arrhythmia may be pursued vertically, as up the rungs of a ladder, from symptom to ECG, to EPS, to local lesion, to intracellular metabolism and to alterations of the latter and their effects on charge-transfer by ions across the cell membrane. Raised intracellular cAMP and calcium concentrations are responses to normal physiological controls, and highly abnormal ECGs occur in normal people under stress without progressing to life threatening arrhythmias, yet do so in susceptible individuals. Conversely, appropriate stimulation can precipitate ventricular fibrillation in normal myocardium. Selective stimulation of different types of adrenoceptor has differing electrophysiological effects. Beta 1-adrenoceptors increase contraction and calcium current, and shorten action potential duration (APD) by increasing potassium conductance. Beta 2-adrenoceptors do not increase calcium entry, but shorten APD by stimulating electrogenic Na/K pumping, alpha-adrenoceptors prolong contractions and lengthen APD. It is suggested that the tachycardia, extrasystoles and shortening of APD occurring in response to adrenergic stimuli and hypoxia, are accessory factors, not primary causes, in the development of arrhythmias, and constitute a danger when there is an appropriate anatomical substrate for re-entry. Serious arrhythmias are of multifactorial origin, of which "calcium overload" is but one, not proven to be a frequent one.
20. Clinical Outcomes from Unselected “Real-World” Patients with Long Coronary Lesion Receiving 40 mm Biodegradable Polymer Coated Sirolimus-Eluting Stent
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Anurag Polavarapu
2015-01-01
Full Text Available Background. Long lesions being implanted with drug-eluting stents (DES are associated with relatively high restenosis rates and higher incidences of adverse events. Objectives. We aimed to examine the safety and efficacy of the long (40 mm biodegradable polymer coated Indolimus sirolimus-eluting stent (SES in real-world patients with long coronary lesions. Methods. This study was observational, nonrandomized, retrospective, and carried out in real-world patients. A total of 258 patients were enrolled for the treatment of long coronary lesions, with 40 mm Indolimus. The primary endpoints in the study were incidence of major adverse cardiac events (MACE, a miscellany of cardiac death, myocardial infarction (MI, target lesion revascularization (TLR or target vessel revascularization (TVR, and stent thrombosis (ST up to 6-month follow-up. Results. The study population included higher proportion of males (74.4% and average age was 53.2 ± 11.0 years. A total of 278 lesions were intervened successfully with 280 stents. The observed MACE at 6-month follow-up was 2.0%, which included 0.8% cardiac death and 1.2% MI. There were no TLR or TVR and ST observed during 6-month follow-up. Conclusions. The long (40 mm Indolimus stent demonstrated low MACE rate and was proven to be safe and effective treatment for long lesions in “real-world” patients.
1. Cardiac Penetrating Injuries and Pseudoaneurysm
Institute of Scientific and Technical Information of China (English)
CHEN Shifeng
2002-01-01
Objective To discuss the early diagnosis and treatment of cardiac penetrating injuries and pseudoaneurysm. Methods 18 cases of cardiac penetrating injuries, in which 2 cases were complicated with pseudoaneurysm, were diagnosed by emergency operation and color Doppler echocardiography between May 1973 and Dec. 2001 in our hospital. The basis for emergency operation is the injured path locating in cardiac dangerous zone, severe shock or pericardial tamponade. ResultsAmong 18 cases of this study, 17 cases underwent emergency operation. During the operation, 11 cases were found injured in right ventricle, 2 cases were found injured in right atrium, 1 case was found injured in pulmonary artery,4 cases were found injured in left ventricle, 2 cases were found complicated with pseudoaneurysm. 17cases underwent cardiac repair including 1 case of rupture of aneurysm. 1 case underwent elective aneurysm resection. In whole group, 15 cases survived(83.33% ), 3 cases died( 16.67%). The cause of death is mainly hemorrhagic shock. Conclusion Highly suspicious cardiac penetrating injuries or hemopericaridium should undergo direct operative exploration. Pseudoaneurysm should be resected early,which can prevent severe complications.
2. Vitamin D and Cardiac Differentiation.
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Kim, Irene M; Norris, Keith C; Artaza, Jorge N
2016-01-01
Calcitriol (1,25-dihydroxycholecalciferol or 1,25-D3) is the hormonally active metabolite of vitamin D. Experimental studies of vitamin D receptors and 1,25-D3 establish calcitriol to be a critical regulator of the structure and function of the heart. Clinical studies link vitamin D deficiency with cardiovascular disease (CVD). Emerging evidence demonstrates that calcitriol is highly involved in CVD-related signaling pathways, particularly the Wnt signaling pathway. Addition of 1,25-D3 to cardiomyocyte cells and examination of its effects on cardiomyocytes and mainly Wnt11 signaling allowed the specific characterization of the role of calcitriol in cardiac differentiation. 1,25-D3 is demonstrated to: (i) inhibit cell proliferation without promoting apoptosis; (ii) decrease expression of genes related to the regulation of the cell cycle; (iii) promote formation of cardiomyotubes; (iv) induce expression of casein kinase-1-α1, a negative regulator of the canonical Wnt signaling pathway; and (v) increase expression of noncanonical Wnt11, which has been recognized to induce cardiac differentiation during embryonic development and in adult cells. Thus, it appears that vitamin D promotes cardiac differentiation through negative modulation of the canonical Wnt signaling pathway and upregulation of noncanonical Wnt11 expression. Future work to elucidate the role(s) of vitamin D in cardiovascular disorders will hopefully lead to improvement and potentially prevention of CVD, including abnormal cardiac differentiation in settings such as postinfarction cardiac remodeling. PMID:26827957
3. Cardiac factors in orthostatic hypotension
Science.gov (United States)
Löllgen, H.; Dirschedl, P.; Koppenhagen, K.; Klein, K. E.
Cardiac function is determined by preload, afterload, heart rate and contractility. During orthostatic stress, the footward blood shift is compensated for by an increase of afterload. LBNP is widely used to analyze effects of volume displacement during orthostatic stress. Comparisons of invasive ( right heart catheterization) and non-invasive approach (echocardiography) yielded similar changes. Preload and afterload change with graded LBNP, heart rate increases, and stroke volume and cardiac output decrease. Thus, the working point on the left ventricular function curve is shifted to the left and downward, similar to hypovolemia. However, position on the Frank-Starling curve, the unchanged ejection fraction, and the constant Vcf indicate a normal contractile state during LBNP. A decrease of arterial oxygen partial pressure during LBNP shwos impaired ventilation/perfusion ratio. Finally, LBNP induced cardiac and hemodynamic changes can be effectively countermeasured by dihydroergotamine, a potent venoconstrictor. Comparison of floating catheter data with that of echocardiography resulted in close correlation for cardiac output and stroke volume. In addition, cardiac dimensions changed in a similar way during LBNP. From our findings, echocardiography as a non-invasive procedure can reliably used in LBNP and orthostatic stress tests. Some informations can be obtained on borderline values indicating collaps or orthostatic syncope. Early fainters can be differentiated from late fainters by stroke volume changes.
4. Animal models of cardiac cachexia.
Science.gov (United States)
Molinari, Francesca; Malara, Natalia; Mollace, Vincenzo; Rosano, Giuseppe; Ferraro, Elisabetta
2016-09-15
Cachexia is the loss of body weight associated with several chronic diseases including chronic heart failure (CHF). The cachectic condition is mainly due to loss of skeletal muscle mass and adipose tissue depletion. The majority of experimental in vivo studies on cachexia rely on animal models of cancer cachexia while a reliable and appropriate model for cardiac cachexia has not yet been established. A critical issue in generating a cardiac cachexia model is that genetic modifications or pharmacological treatments impairing the heart functionality and used to obtain the heart failure model might likely impair the skeletal muscle, this also being a striated muscle and sharing with the myocardium several molecular and physiological mechanisms. On the other hand, often, the induction of heart damage in the several existing models of heart failure does not necessarily lead to skeletal muscle loss and cachexia. Here we describe the main features of cardiac cachexia and illustrate some animal models proposed for cardiac cachexia studies; they include the genetic calsequestrin and Dahl salt-sensitive models, the monocrotaline model and the surgical models obtained by left anterior descending (LAD) ligation, transverse aortic constriction (TAC) and ascending aortic banding. The availability of a specific animal model for cardiac cachexia is a crucial issue since, besides the common aspects of cachexia in the different syndromes, each disease has some peculiarities in its etiology and pathophysiology leading to cachexia. Such peculiarities need to be unraveled in order to find new targets for effective therapies. PMID:27317993
5. Epicardial Lineages and Cardiac Repair
Directory of Open Access Journals (Sweden)
Manvendra K. Singh
2013-08-01
Full Text Available The death of cardiac myocytes resulting from myocardial infarction is a major cause of heart failure worldwide. Effective therapies for regenerating lost cardiac myocytes are lacking. Recently, the epicardium has been implicated as a source of inflammatory cytokines, growth factors and progenitor cells that modulate the response to myocardial injury. During embryonic development, epicardially-derived cells have the potential to differentiate into multiple cardiac lineages, including fibroblasts, vascular smooth muscle and potentially other cell types. In the healthy adult heart, epicardial cells are thought to be generally quiescent. However, injury of the adult heart results in reactivation of a developmental gene program in the epicardium, which leads to increased epicardial cell proliferation and differentiation of epicardium-derived cells (EPDCs into various cardiac lineages. Recent work suggests that epicardial reactivation after injury is accompanied by, and contributes to, a robust inflammatory response. In this review, we describe the current status of research related to epicardial biology in cardiac development and regeneration, highlighting important recent discoveries and ongoing controversies.
6. 3D engineered cardiac tissue models of human heart disease: learning more from our mice.
Science.gov (United States)
Ralphe, J Carter; de Lange, Willem J
2013-02-01
Mouse engineered cardiac tissue constructs (mECTs) are a new tool available to study human forms of genetic heart disease within the laboratory. The cultured strips of cardiac cells generate physiologic calcium transients and twitch force, and respond to electrical pacing and adrenergic stimulation. The mECT can be made using cells from existing mouse models of cardiac disease, providing a robust readout of contractile performance and allowing a rapid assessment of genotype-phenotype correlations and responses to therapies. mECT represents an efficient and economical extension to the existing tools for studying cardiac physiology. Human ECTs generated from iPSCMs represent the next logical step for this technology and offer significant promise of an integrated, fully human, cardiac tissue model.
7. Identification of genes regulated during mechanical load-induced cardiac hypertrophy
Science.gov (United States)
Johnatty, S. E.; Dyck, J. R.; Michael, L. H.; Olson, E. N.; Abdellatif, M.; Schneider, M. (Principal Investigator)
2000-01-01
Cardiac hypertrophy is associated with both adaptive and adverse changes in gene expression. To identify genes regulated by pressure overload, we performed suppressive subtractive hybridization between cDNA from the hearts of aortic-banded (7-day) and sham-operated mice. In parallel, we performed a subtraction between an adult and a neonatal heart, for the purpose of comparing different forms of cardiac hypertrophy. Sequencing more than 100 clones led to the identification of an array of functionally known (70%) and unknown genes (30%) that are upregulated during cardiac growth. At least nine of those genes were preferentially expressed in both the neonatal and pressure over-load hearts alike. Using Northern blot analysis to investigate whether some of the identified genes were upregulated in the load-independent calcineurin-induced cardiac hypertrophy mouse model, revealed its incomplete similarity with the former models of cardiac growth. Copyright 2000 Academic Press.
8. Cardiac perioperative complications in noncardiac surgery
Directory of Open Access Journals (Sweden)
2008-01-01
Full Text Available Anesthesiologists are confronted with an increasing population of patients undergoing noncardiac surgery who are at risk for cardiac complications in the perioperative period. Perioperative cardiac complications are responsible for significant mortality and morbidity. The aim of the present study was to determine the incidence of perioperative (operative and postoperative cardiac complications and correlations between the incidence of perioperative cardiac complications and type of surgical procedure, age, presence of concurrent diseases. A total of 100 patients with cardiac diseases undergoing noncardiac surgery were included in the prospective study (Group A 50 patients undergoing intraperitoneal surgery and Group B 50 patients undergoing breast and thyroid surgery. The patients were followed up during the perioperative period and after surgery until leaving hospital to assess the occurrence of cardiac events. Cardiac complications (systemic arterial hypertension, systemic arterial hypotension, abnormalities of cardiac conduction and cardiac rhythm, perioperative myocardial ischemia and acute myocardial infarction occurred in 64% of the patients. One of the 100 patients (1% had postoperative myocardial infarction which was fatal. Systemic arterial hypertension occurred in 57% of patients intraoperatively and 33% postoperatively, abnormalities of cardiac rhythm in 31% of patients intraoperatively and 17% postoperatively, perioperative myocardial ischemia in 23% of patients intraoperatively and 11% of postoperatively. The most often cardiac complications were systemic arterial hypertension, abnormalities of cardiac rhythm and perioperative myocardial ischemia. Factors independently associated with the incidence of cardiac complications included the type of surgical procedure, advanced age, duration of anaesthesia and surgery, abnormal preoperative electrocardiogram, abnormal preoperative chest radiography and diabetes.
9. Characterization of troponin responses in isoproterenol-induced cardiac injury in the Hanover Wistar rat.
Science.gov (United States)
York, Malcolm; Scudamore, Cheryl; Brady, Sally; Chen, Christabelle; Wilson, Sharon; Curtis, Mark; Evans, Gareth; Griffiths, William; Whayman, Matthew; Williams, Thomas; Turton, John
2007-06-01
The investigations aimed to evaluate the usefulness of cardiac troponins as biomarkers of acute myocardial injury in the rat. Serum from female Hanover Wistar rats treated with a single intraperitoneal (IP) injection of isoproterenol (ISO) was assayed for cardiac troponin I (cTnI) (ACS: 180SE, Bayer), cTnI (Immulite 2000, Diagnostic Products Corporation) and cardiac troponin T (cTnT) (Elecsys 2010, Roche). In a time-course study (50.0 mg/kg ISO), serum cTnI (ACS:180SE) and cTnT increased above control levels at 1 hour postdosing, peaking at 2 hours (cTnI, 4.30 microg/L; cTnT, 1.79 microg/L), and declined to baseline by 48 hours, with histologic cardiac lesions first seen at 4 hours postdosing. The Immulite 2000 assay gave minimal cTnI signals, indicating poor immunoreactivity towards rat cTnI. In a dose-response study (0.25 to 20.0 mg/kg ISO), there was a trend for increasing cTnI (ACS:180SE) values with increasing ISO dose levels at 2 hours postdosing. By 24 hours, cTnI levels returned to baseline although chronic cardiac myodegeneration was present. We conclude that serum cTnI and cTnT levels are sensitive and specific biomarkers for detecting ISO induced myocardial injury in the rat. Serum troponin values reflect the development of histopathologic lesions; however peak troponin levels precede maximal lesion severity.
10. Surgical treatment of gallbladder polypoid lesions
OpenAIRE
Pejić Miljko A.; Milić Dragan J.
2003-01-01
INTRODUCTION Polypoid lesions of the gallbladder can be divided into benign and malignant categories. Malignant polypoid lesions include carcinomas of the gallbladder, which is the fifth most common malignancy of the gastrointestinal tract and the most common malignancy of the biliary tract. Benign polypoid lesions of the gallbladder are divided into true tumors and pseudotumors. Pseudotumors account for most of polypoid lesions of the gallbladder, and include polyps, hyperplasia, and other m...
11. Unusual cause of generalized osteolytic vertebral lesions: a case report
Directory of Open Access Journals (Sweden)
Nanda Sudip
2007-06-01
Full Text Available Abstract Background Vertebral sarcoidosis is an extremely rare form of osseous sarcoidosis. Although osseous sarcoidosis is almost always an incidental finding of sarcoidosis elsewhere in the body, vertebrae may be the primary disease site. Involvement of vertebrae is usually localized and sclerotic or lytic. Case presentation We describe a case of extensive asymptomatic vertebral involvement by sarcoid with osteolytic lesions. Making the diagnosis requires biopsy and ruling out other commoner causes of osteolytic vertebral lesions. Conclusion We report this case in the hope of expanding the knowledge of osseous sarcoidosis. Our patient was unique in that all involvement was axial with sparing of the peripheral skeleton, near absence of any other organ involvement, diffuse involvement of the whole spine and osteolytic bone lesions.
12. In Vivo Tracking of Cell Therapies for Cardiac Diseases with Nuclear Medicine
Science.gov (United States)
Moreira, Mayra Lorena; da Costa Medeiros, Priscylla; de Souza, Sergio Augusto Lopes; Rosado-de-Castro, Paulo Henrique
2016-01-01
Even though heart diseases are amongst the main causes of mortality and morbidity in the world, existing treatments are limited in restoring cardiac lesions. Cell transplantations, originally developed for the treatment of hematologic ailments, are presently being explored in preclinical and clinical trials for cardiac diseases. Nonetheless, little is known about the possible efficacy and mechanisms for these therapies and they are the center of continuous investigation. In this scenario, noninvasive imaging techniques lead to greater comprehension of cell therapies. Radiopharmaceutical cell labeling, firstly developed to track leukocytes, has been used successfully to evaluate the migration of cell therapies for myocardial diseases. A substantial rise in the amount of reports employing this methodology has taken place in the previous years. We will review the diverse radiopharmaceuticals, imaging modalities, and results of experimental and clinical studies published until now. Also, we report on current limitations and potential advances of radiopharmaceutical labeling for cell therapies in cardiac diseases. PMID:26880951
13. Anaesthetic management of patients with congenital heart disease presenting for non-cardiac surgery.
OpenAIRE
Mohindra R; Beebe David; Belani Kumar
2002-01-01
The incidence of congenital heart disease is about one percent of all live births in the United States. Treatment is being performed at a younger age and these children are showing improved survival. It is not unusual for children with congenital heart disease to present for non-cardiac surgery. Their management depends on their age, type of lesion, extent of corrective procedure, the presence of complications and other congenital anomalies. Each patient needs a detailed pre-operative evaluat...
14. Electrophysiological Cardiac Modeling: A Review.
Science.gov (United States)
Beheshti, Mohammadali; Umapathy, Karthikeyan; Krishnan, Sridhar
2016-01-01
Cardiac electrophysiological modeling in conjunction with experimental and clinical findings has contributed to better understanding of electrophysiological phenomena in various species. As our knowledge on underlying electrical, mechanical, and chemical processes has improved over time, mathematical models of the cardiac electrophysiology have become more realistic and detailed. These models have provided a testbed for various hypotheses and conditions that may not be easy to implement experimentally. In addition to the limitations in experimentally validating various scenarios implemented by the models, one of the major obstacles for these models is computational complexity. However, the ever-increasing computational power of supercomputers facilitates the clinical application of cardiac electrophysiological models. The potential clinical applications include testing and predicting effects of pharmaceutical agents and performing patient-specific ablation and defibrillation. A review of studies involving these models and their major findings are provided.
15. Lesion Contrast Enhancement in Medical Ultrasound Imaging
DEFF Research Database (Denmark)
Stetson, Paul F.; Sommer, F.G.; Macovski, A.
1997-01-01
Methods for improving the contrast-to-noise ratio (CNR) of low-contrast lesions in medical ultrasound imaging are described. Differences in the frequency spectra and amplitude distributions of the lesion and its surroundings can be used to increase the CNR of the lesion relative to the background...
16. Is Training Essential for Interpreting Cardiac Computed Tomography
International Nuclear Information System (INIS)
17. Complications after cardiac implantable electronic device implantations
DEFF Research Database (Denmark)
Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard;
2013-01-01
Complications after cardiac implantable electronic device (CIED) treatment, including permanent pacemakers (PMs), cardiac resynchronization therapy devices with defibrillators (CRT-Ds) or without (CRT-Ps), and implantable cardioverter defibrillators (ICDs), are associated with increased patient...
18. Sudden Cardiac Arrest (SCA) Risk Assessment
Science.gov (United States)
... Find a Specialist Share Twitter Facebook SCA Risk Assessment Sudden Cardiac Arrest (SCA) occurs abruptly and without ... of all ages and health conditions. Start Risk Assessment The Sudden Cardiac Arrest (SCA) Risk Assessment Tool ...
19. An update on insertable cardiac monitors
DEFF Research Database (Denmark)
Olsen, Flemming J; Biering-Sørensen, Tor; Krieger, Derk W
2015-01-01
Continuous cardiac rhythm monitoring has undergone compelling progress over the past decades. Cardiac monitoring has emerged from 12-lead electrocardiograms being performed at the discretion of the treating physician to in-hospital telemetry, Holter monitoring, prolonged external event monitoring...
20. Elevated sensitivity to cardiac ischemia in proteinuric rats is independent of adverse cardiac remodeling
NARCIS (Netherlands)
Szymanski, Mariusz K.; Hillege, Hans L.; Danser, A. H. Jan; Garrelds, Ingrid M.; Schoemaker, Regien G.
2013-01-01
Objectives: Chronic renal dysfunction severely increases cardiovascular risk. Adverse cardiac remodeling is suggested to play a major role as predisposition for increased cardiac ischemic vulnerability. The aim of the present study was to examine the role of adverse cardiac remodeling in cardiac sen
1. Cardiac myxoma: A surgical experience of 38 patients over 9 years, at SSKM hospital Kolkata, India
Directory of Open Access Journals (Sweden)
2013-01-01
Full Text Available Background: Cardiac myxoma is the most common benign intracardiac tumor. We studied its clinical presentation, morbidity, mortality and recurrence following surgery over a period of 9 years. Materials and Methods: This study was performed at cardiothoracic and vascular surgery department of a tertiary level hospital of eastern India, Seth Sukhlal Karnani Memorial hospital, Institute of Post Graduate Medical Education and Research Kolkata. Near 6000 cardiac cases were operated at our center over this period. Preoperative diagnosis was made with clinical presentation and preoperative echocardiography. Complete tumor excision was done and all patients were followed up for recurrence and complications. Result: A total of 38 cases of cardiac myxoma were operated over a period from October 2002 to October 2011. Cardiac myxoma constituted about 0.6% of all cardiac cases operated at our institute. This most commonly presented at fifth decade of life. Of these, 35 cases were left atrial and 2 cases were right atrial, and 1 case was having both atrial involvements. The left atrial myxoma mostly presented as mitral stenosis and very few presented with embolic and constitutional symptoms. No death or recurrence was observed during the follow up period. Conclusion: Cardiac myxomas form a very small percentage of the cardiac cases. A high index of suspicion is essential for diagnosis. Echocardiography is the ideal diagnostic tool as also for follow-up. Immediate surgical treatment is indicated in all patients. Cardiac myxomas can be excised with a low rate of mortality and morbidity.
2. [Cardiac output monitoring by impedance cardiography in cardiac surgery].
Science.gov (United States)
Shimizu, H; Seki, S; Mizuguchi, A; Tsuchida, H; Watanabe, H; Namiki, A
1990-04-01
The cardiac output monitoring by impedance cardiography, NCCOM3, was evaluated in adult patients (n = 12) who were subjected to coronary artery bypass grafting. Values of cardiac output measured by impedance cardiography were compared to those by the thermodilution method. Changes of base impedance level used as an index of thoracic fluid volume were also investigated before and after cardiopulmonary bypass (CPB). Correlation coefficient (r) of the values obtained by thermodilution with impedance cardiography was 0.79 and the mean difference was 1.29 +/- 16.9 (SD)% during induction of anesthesia. During the operation, r was 0.83 and the mean difference was -14.6 +/- 18.7%. The measurement by impedance cardiography could be carried out through the operation except when electro-cautery was used. Base impedance level before CPB was significantly lower as compared with that after CPB. There was a negative correlation between the base impedance level and central venous pressure (CVP). No patients showed any signs suggesting lung edema and all the values of CVP, pulmonary artery pressure and blood gas analysis were within normal ranges. From the result of this study, it was concluded that cardiac output monitoring by impedance cardiography was useful in cardiac surgery, but further detailed examinations will be necessary on the relationship between the numerical values of base impedance and the clinical state of the patients. PMID:2362347
3. Health Literacy Predicts Cardiac Knowledge Gains in Cardiac Rehabilitation Participants
Science.gov (United States)
Mattson, Colleen C.; Rawson, Katherine; Hughes, Joel W.; Waechter, Donna; Rosneck, James
2015-01-01
Objective: Health literacy is increasingly recognised as a potentially important patient characteristic related to patient education efforts. We evaluated whether health literacy would predict gains in knowledge after completion of patient education in cardiac rehabilitation. Method: This was a re-post observational analysis study design based on…
4. Regulation of Cardiac Hypertrophy: the nuclear option
OpenAIRE
Kuster, Diederik
2011-01-01
textabstractCardiac hypertrophy is the response of the heart to an increased workload. After myocardial infarction (MI) the surviving muscle tissue has to work harder to maintain cardiac output. This sustained increase in workload leads to cardiac hypertrophy. Despite its apparent appropriateness, cardiac hypertrophy is an independent risk factor for the development of heart failure and is therefore called pathological hypertrophy. That hypertrophy is not bad per se, is illustrated by the hyp...
5. Structure and mechanism for DNA lesion recognition
Institute of Scientific and Technical Information of China (English)
Wei Yang
2008-01-01
A fundamental question in DNA repair is how a lesion is detected when embedded in millions to billions of normal base pairs. Extensive structural and functional studies reveal atomic details of DNA repair protein and nucleic acid interactions. This review summarizes seemingly diverse structural motifs used in lesion recognition and suggests a general mechanism to recognize DNA lesion by the poor base stacking. After initial recognition of this shared struc-tural feature of lesions, different DNA repair pathways use unique verification mechanisms to ensure correct lesion identification and removal.
6. Solitary lucent epiphyseal lesions in children
Energy Technology Data Exchange (ETDEWEB)
Gardner, D.J.; Azouz, E.M.
1988-10-01
We evaluated retrospectively the varying radiographic appearances of 15 solitary lucent epiphyseal lesions occurring in children. Imaging modalities used included plain films, conventional tomography, nuclear scintigraphy, and computed tomography. 40% of the lesions (6) were due to osteomyelitis. The remaining lesions included tuberculosis (1), foreign body granuloma (1), chondroblastoma (2), chondromyoxid fibroma (1), enchondroma (1), osteoid osteoma (2), and eosinophilic granuloma (1). Although the radiographic appearances of such lesions may be particularly characteristic, pathologic correlation is frequently necessary. The high incidence of osteomyelitis in our cases emphasizes its importance as a cause for a lucent epiphyseal lesion.
7. Self-inflicted skin lesions
DEFF Research Database (Denmark)
Ring, Hans Christian; Smith, Matthias Nybro; Jemec, Gregor B E
2014-01-01
The current literature on the management of self-inflicted skin lesions points to an overall paucity of treatments with a high level of evidence (randomized controlled trials, controlled trials, or meta-analyses). In order to improve the communication between dermatologists and mental health...... the previous plethora of terms is covered by the new classification. This may aid physicians and mental health professionals in understanding how the new classification relates to the prior plethora of psychodermatological diagnoses and thereby facilitate the future use of the new classification....
8. Pancreatic Lesion: Malignancy or Abscess?
Science.gov (United States)
Shulik, Oleg; Cavanagh, Yana; Grossman, Matthew
2016-01-01
BACKGROUND Pancreatic abscesses are rare. They may be seen in patients with pancreatic inflammation or pancreatitis. Patients with pancreatic abscesses may have abdominal pain, fever, chills, and nausea/vomiting or an inability to eat. Presentation with alternate symptomatology is extremely unusual. CASE REPORT A 67-year-old Asian male presented with painless, afebrile obstructive jaundice and a CA 19-9 of 1732 IU. He was found to have a 3.1×2.4 cm low-density lesion in the head of the pancreas and the right lobe of the liver, suggesting malignancy. Surgical management was considered, however additional diagnostic workup, including an endoscopic retrograde cholangiopancreatography (ERCP), was performed to complete staging of the presumed mass. A smooth, 3-cm-long, tapering stricture was found it the common bile duct. It was stented from the common hepatic duct to the duodenum. Subsequent endoscopic ultrasound (EUS) evaluation of the pancreatic head lesion revealed a drainable fluid collection that was aspirated and found to contain pyogenic material on pathology. The patient's symptoms resolved, and he was subsequently managed conservatively. A repeat ERCP confirmed complete resolution of the previously visualized cystic lesion. Interestingly, laboratory values showed concomitant normalization of CA 19-9 to 40 IU. CONCLUSIONS EUS-guided biopsy is not widely regarded as a required step before surgery, in the management of patients with pancreatic masses. It is generally reserved for determination of resectability or staging, and only utilized when clinically indicated. However, this practice may be associated with an inherently significant risk of misdiagnosis and subsequent unnecessary surgery, as illustrated by this case. Malignancy was initially suspected in our patient and surgical resection was recommended. Endoscopic measures were only pursued to complete staging. We propose that EUS-guided biopsy may be a crucial diagnostic step in the management algorithm
9. MRI of cardiac rhabdomyoma in the fetus
Energy Technology Data Exchange (ETDEWEB)
Kivelitz, Dietmar E.; Muehler, Matthias [Institut fuer Radiologie, Medizinische Fakultaet, Humboldt-Universitaet zu Berlin, Charite, Schumannstrasse 20/21, 10098, Berlin (Germany); Rake, Annett; Chaoui, Rabih [Klinik fuer Gynaekologie und Geburtshilfe, Medizinische Fakultaet, Humboldt-Universitaet zu Berlin, Charite, Schumannstrasse 20/21, 10098, Berlin (Germany); Scheer, Ianina [Klinik fuer Strahlenheilkunde, Abteilung Paediatrische Radiologie, Medizinische Fakultaet, Humboldt-Universitaet zu Berlin, Charite, Schumannstrasse 20/21, 10098, Berlin (Germany)
2004-08-01
Primary cardiac tumors are rarely diagnosed in utero and are usually seen on prenatal echocardiography. Cardiac rhabdomyomata can be associated with tuberous sclerosis. Prenatal MRI can be performed to assess associated malformations. This case report illustrates the ability of fetal MRI to image cardiac rhabdomyata and compares it with prenatal and postnatal echocardiography. (orig.)
10. Regulation of Cardiac Hypertrophy: the nuclear option
NARCIS (Netherlands)
D.W.D. Kuster (Diederik)
2011-01-01
textabstractCardiac hypertrophy is the response of the heart to an increased workload. After myocardial infarction (MI) the surviving muscle tissue has to work harder to maintain cardiac output. This sustained increase in workload leads to cardiac hypertrophy. Despite its apparent appropriateness, c
11. Childhood cancer survivors: cardiac disease & social outcomes
NARCIS (Netherlands)
E.A.M. Feijen
2015-01-01
The thesis is divided in two parts; Cardiac health problems and healthcare consumption & social outcomes in CCS. The general aims of part 1 creates optimal conditions for the evaluation of cardiac events in 5-year childhood cancer survivors, evaluation of the long term risk of cardiac events, and to
12. Dieulafoy's lesion of duodenum: a case report
Directory of Open Access Journals (Sweden)
Wagholikar Gajanan D
2003-01-01
Full Text Available Abstract Background Dieulafoy's lesion is an uncommon but important cause of recurrent upper gastrointestinal bleeding. Extragastric location of Dieulafoy's lesion is rare. We report two cases of Dieulafoy's lesion of the duodenum and discuss the management of this extremely uncommon entity. Case presentation Two cases of massive upper gastro-intestinal bleeding in young adults due to Dieulafoy's lesion of the duodenum are reported. Endoscopic diagnosis was possible in both cases. Hemostasis was achieved successfully by endoscopic adrenaline injection. The endoscopic appearance, pitfalls in the diagnosis and management of this rare lesion are discussed. Conclusions Endoscopic diagnosis of extragastric Dieulafoy's lesion can be difficult because of the small size and obscure location of the lesion. Increased awareness and careful and early endoscopic evaluation following the bleeding episode are the key to accurate diagnosis. Adrenaline injection is one of the important endoscopic modalities for control of bleeding.
13. Cardiac abnormalities after subarachnoid hemorrhage
NARCIS (Netherlands)
Bilt, I.A.C. van der
2016-01-01
Aneurysmal subarachnoid hemorrhage(aSAH) is a devastating neurological disease. During the course of the aSAH several neurological and medical complications may occur. Cardiac abnormalities after aSAH are observed often and resemble stress cardiomyopathy or Tako-tsubo cardiomyopathy(Broken Heart Syn
14. Molecular therapies for cardiac arrhythmias
NARCIS (Netherlands)
G.J.J. Boink
2013-01-01
Despite the ongoing advances in pharmacology, devices and surgical approaches to treat heart rhythm disturbances, arrhythmias are still a significant cause of death and morbidity. With the introduction of gene and cell therapy, new avenues have arrived for the local modulation of cardiac disease. Th
15. Historical highlights in cardiac pacing.
Science.gov (United States)
Geddes, L A
1990-01-01
The benchmarks in cardiac pacing are identified, beginning with F. Steiner (1871), who rhythmically stimulated the chloroform-arrested hearts of 3 horses, 1 donkey, 10 dogs, 14 cats, and 8 rabbits. The chloroform-arrested heart in human subjects was paced by T. Greene in the following year (1872) in the UK. In 1882, H. Ziemssen in Germany applied cardiac pacing to a 42-year old woman who had a large defect in the anterior left chest wall subsequent to resection of an enchondroma. Intentional cardiac pacing did not occur until 1932, when A.A. Hyman in the US demonstrated that cardiac pacing could be clinically practical. Hyman made a batteryless pacemaker for delivery in induction shock stimuli (60-120/min) to the atria. His pacemaker was powered by a hand-wound, spring-driven generator which provided 6 min of pacemaking without rewinding. Closed-chest ventricular pacing was introduced in the US in 1952 by P.M. Zoll et al. Zoll (1956) also introduced closed-chest ventricular defibrillation. W.L. Weirich et al. (1958) demonstrated that direct-heart stimulation in closed-chest patients could be achieved with slender wire electrodes. S. Furman and J.B. Schwedel (1959) developed a monopolar catheter electrode for ventricular pacing in man. In the same year, W. Greatbatch and W.M. Chardack developed the implantable pacemaker. PMID:18238328
16. Cardiac resynchronization therapy in China
Institute of Scientific and Technical Information of China (English)
Wei HUA
2006-01-01
@@ Congestive heart failure (HF) is a major and growing public health problem. The therapeutic approach includes non-pharmacological measures, pharmacological therapy,mechanical devices, and surgery. Despite the benefits of optimal pharmacologic therapy, the prognosis is still not ideal. At this time, cardiac resynchronization therapy (CRT)has gained wide acceptance as an alternative treatment for HF patients with conduction delay.1
17. Cardiac pacemakers and nuclear batteries
International Nuclear Information System (INIS)
Following the introduction giving the indications for cardiac pacemaker therapy with special regard to the use of pacemakers powered by nuclear batteries, reference is made to the resulting radiation exposure of the patient. The activities of the Federal Health Office in this field such as recommendations and surveys including the entire Federal Republic are outlined. (orig.)
18. Epidural analgesia for cardiac surgery
NARCIS (Netherlands)
V. Svircevic; M.M. Passier; A.P. Nierich; D. van Dijk; C.J. Kalkman; G.J. van der Heijden
2013-01-01
Background A combination of general anaesthesia (GA) with thoracic epidural analgesia (TEA) may have a beneficial effect on clinical outcomes by reducing the risk of perioperative complications after cardiac surgery. Objectives The objective of this review was to determine the impact of perioperativ
19. Collecting Duct Carcinoma With Cardiac Metastases: A Case Report & Literature Review
Directory of Open Access Journals (Sweden)
James N. Voss
2016-03-01
Full Text Available Collecting duct carcinoma (CDC, is a rare and aggressive form of renal cell carcinoma (RCC accounting for around 1% of all renal malignancy. It affects younger patients and is associated with rapid progression, distant spread and poor prognosis. Cardiac metastases from all types of RCC, without involvement of the inferior vena cava are very rare. We present the case of a 54 year old man with a history of CDC, who presents with collapse and ventricular tachycardia secondary to multifocal cardiac metastases. We are not aware of any other reports in the literature of CDC and cardiac metastases.
20. Randomized Comparison of the Crush Versus the Culotte Stenting for Coronary Artery Bifurcation Lesions
Institute of Scientific and Technical Information of China (English)
Xu-Wei Zheng; Dong-Hui Zhao; Hong-Yu Peng; Qian Fan; Qin Ma; Zhen-Ye Xu; Chao Fan
2016-01-01
Background:The crush and the culotte stenting were both reported to be effective for complex bifurcation lesion treatment.However,their comparative performance remains elusive.Methods:A total of 300 patients with coronary bifurcation lesions were randomly assigned to crush (n =150) and culotte (n =150) treatment.The primary endpoint was the occurrence of major adverse cardiac events (MACEs) at 12 months including cardiac death,myocardial infarction,stent thrombosis,and target vessel revascularization.Index lesion restenosis at 12 months was a secondary endpoint.The surface integrals of time-averaged wall shear stress at bifurcation sites were also be quantified.Results:There were no significant differences in MACE rates between the two groups at 12-month follow-up:Crush 6.7％,culotte 5.3％ (P =0.48).The rates of index lesion restenosis were 12.7％ versus 6.0％ (P =0.047) in the crush and the culotte groups,respectively.At 12-month follow-up,the surface integrals of time-averaged wall shear stress at bifurcation sites in the crush group were significantly lower than the culotte group ([5.01 ± 0.95] × 10-4 Newton and [6.08 ± 1.16] × 10 4 Newton,respectively;P =0.003).Conclusions:Both the crush and the culotte bifurcation stenting techniques showed satisfying clinical and angiographic results at 12-month follow-up.Bifurcation lesions treated with the culotte technique tended to have lower restenosis rates and more favorable flow patterns.
1. Cardiac tissue ablation with catheter-based microwave heating.
Science.gov (United States)
Rappaport, C
2004-11-01
The common condition of atrial fibrillation is often treated by cutting diseased cardiac tissue to disrupt abnormal electrical conduction pathways. Heating abnormal tissue with electromagnetic power provides a minimally invasive surgical alternative to treat these cardiac arrhythmias. Radio frequency ablation has become the method of choice of many physicians. Recently, microwave power has also been shown to have great therapeutic benefit in medical treatment requiring precise heating of biological tissue. Since microwave power tends to be deposited throughout the volume of biological media, microwave heating offers advantages over other heating modalities that tend to heat primarily the contacting surface. It is also possible to heat a deeper volume of tissue with more precise control using microwaves than with purely thermal conduction or RF electrode heating. Microwave Cardiac Ablation (MCA) is used to treat heart tissue that allows abnormal electrical conduction by heating it to the point of inactivation. Microwave antennas that fit within catheter systems can be positioned close to diseased tissue. Specialized antenna designs that unfurl from the catheter within the heart can then radiate specifically shaped fields, which overcome problems such as excessive surface heating at the contact point. The state of the art in MCA is reviewed in this paper and a novel catheter-based unfurling wide aperture antenna is described. This antenna consists of the centre conductor of a coaxial line, shaped into a spiral and insulated from blood and tissue by a non-conductive fluid filled balloon. Initially stretched straight inside a catheter for transluminal guiding, once in place at the cardiac target, the coiled spiral antenna is advanced into the inflated balloon. Power is applied in the range of 50-150 W at the reserved industrial, scientific and medical (ISM) frequency of 915 MHz for 30-90 s to create an irreversible lesion. The antenna is then retracted back into the
2. Percutaneous acetabuloplasty for metastatic acetabular lesions
Directory of Open Access Journals (Sweden)
Logroscino Giandomenico
2008-05-01
Full Text Available Abstract Background Osteolytic metastases around the acetabulum are frequent in tumour patients, and may cause intense and drug-resistant pain of the hip. These lesions also cause structural weakening of the pelvis, limping, and poor quality of life. Percutaneous acetabuloplasty is a mini-invasive procedure for the management of metastatic lesions due to carcinoma of the acetabulum performed in patients who cannot tolerate major surgery, or in patients towards whom radiotherapy had already proved ineffective. Methods We report a retrospective study in 25 such patients (30 acetabuli who were evaluated before and after percutaneous acetabuloplasty, with regard to pain, mobility of the hip joint, use of analgesics, by means of evaluation forms: Visual Analog Scale, Harris Hip Score, Western Ontario and McMaster Universities Index of Osteoarthritis (WOMAC, Eastern Cooperative Oncology Group (ECOG. The results obtained were analysed using the χ2 Test and Fisher's exact test. Significance was sent at P Results Marked clinical improvement was observed in all patients during the first six post-operative months, with gradual a worsening thereafter from deterioration of their general condition. Complete pain relief was achieved in 15 of our 25 (59% of patients, and pain reduction was achieved in the remaining 10 (41% patients. The mean duration of pain relief was 7.3 months. Pain recurred in three patients (12% between 2 weeks to 3 months. No major complications occurred. There was transient local pain in most cases, and 2 cases of venous injection of cement without clinical consequences. Conclusion Percutaneous acetabuloplasty is effective in improving the quality of life of patients with osteolytic bone tumours, even though the improvement is observed during the first 6 months only. It can be an effective aid to chemo- and radiotherapy in the management of acetabular metastases.
3. Transthyretin Cardiac Amyloidosis in Black Americans.
Science.gov (United States)
Shah, Keyur B; Mankad, Anit K; Castano, Adam; Akinboboye, Olakunle O; Duncan, Phillip B; Fergus, Icilma V; Maurer, Mathew S
2016-06-01
Transthyretin-related cardiac amyloidosis is a progressive infiltrative cardiomyopathy that mimics hypertensive and hypertrophic heart disease and often goes undiagnosed. In the United States, the hereditary form disproportionately afflicts black Americans, who when compared with whites with wild-type transthyretin amyloidosis, a phenotypically similar condition, present with more advanced disease despite having a noninvasive method for early identification (genetic testing). Although reasons for this are unclear, this begs to consider the inadequate access to care, societal factors, or a biological basis. In an effort to improve awareness and explore unique characteristics, we review the pathophysiology, epidemiology, and therapeutic strategies for transthyretin amyloidosis and highlight diagnostic pitfalls and clinical pearls for identifying patients with amyloid heart disease. PMID:27188913
4. Filters in 2D and 3D Cardiac SPECT Image Processing
Directory of Open Access Journals (Sweden)
Maria Lyra
2014-01-01
Full Text Available Nuclear cardiac imaging is a noninvasive, sensitive method providing information on cardiac structure and physiology. Single photon emission tomography (SPECT evaluates myocardial perfusion, viability, and function and is widely used in clinical routine. The quality of the tomographic image is a key for accurate diagnosis. Image filtering, a mathematical processing, compensates for loss of detail in an image while reducing image noise, and it can improve the image resolution and limit the degradation of the image. SPECT images are then reconstructed, either by filter back projection (FBP analytical technique or iteratively, by algebraic methods. The aim of this study is to review filters in cardiac 2D, 3D, and 4D SPECT applications and how these affect the image quality mirroring the diagnostic accuracy of SPECT images. Several filters, including the Hanning, Butterworth, and Parzen filters, were evaluated in combination with the two reconstruction methods as well as with a specified MatLab program. Results showed that for both 3D and 4D cardiac SPECT the Butterworth filter, for different critical frequencies and orders, produced the best results. Between the two reconstruction methods, the iterative one might be more appropriate for cardiac SPECT, since it improves lesion detectability due to the significant improvement of image contrast.
5. Assessment of factors that influence weaning from long-term mechanical ventilation after cardiac surgery
Directory of Open Access Journals (Sweden)
Emília Nozawa
2003-03-01
Full Text Available OBJECTIVE: To analyze parameters of respiratory system mechanics and oxygenation and cardiovascular alterations involved in weaning tracheostomized patients from long-term mechanical ventilation after cardiac surgery. METHODS: We studied 45 patients in their postoperative period of cardiac surgery, who required long-term mechanical ventilation for more than 10 days and had to undergo tracheostomy due to unsuccessful weaning from mechanical ventilation. The parameters of respiratory system mechanics, oxigenation and the following factors were analyzed: type of surgical procedure, presence of cardiac dysfunction, time of extracorporeal circulation, and presence of neurologic lesions. RESULTS: Of the 45 patients studied, successful weaning from mechanical ventilation was achieved in 22 patients, while the procedure was unsuccessful in 23 patients. No statistically significant difference was observed between the groups in regard to static pulmonary compliance (p=0.23, airway resistance (p=0.21, and the dead space/tidal volume ratio (p=0.54. No difference was also observed in regard to the variables PaO2/FiO2 ratio (p=0.86, rapid and superficial respiration index (p=0.48, and carbon dioxide arterial pressure (p=0.86. Cardiac dysfunction and time of extracorporeal circulation showed a significant difference. CONCLUSION: Data on respiratory system mechanics and oxygenation were not parameters for assessing the success or failure. Cardiac dysfunction and time of cardiopulmonary bypass, however, significantly interfered with the success in weaning patients from mechanical ventilation.
6. Automatic differentiation of melanoma and clark nevus skin lesions
Science.gov (United States)
LeAnder, R. W.; Kasture, A.; Pandey, A.; Umbaugh, S. E.
2007-03-01
Skin cancer is the most common form of cancer in the United States. Although melanoma accounts for just 11% of all types of skin cancer, it is responsible for most of the deaths, claiming more than 7910 lives annually. Melanoma is visually difficult for clinicians to differentiate from Clark nevus lesions which are benign. The application of pattern recognition techniques to these lesions may be useful as an educational tool for teaching physicians to differentiate lesions, as well as for contributing information about the essential optical characteristics that identify them. Purpose: This study sought to find the most effective features to extract from melanoma, melanoma in situ and Clark nevus lesions, and to find the most effective pattern-classification criteria and algorithms for differentiating those lesions, using the Computer Vision and Image Processing Tools (CVIPtools) software package. Methods: Due to changes in ambient lighting during the photographic process, color differences between images can occur. These differences were minimized by capturing dermoscopic images instead of photographic images. Differences in skin color between patients were minimized via image color normalization, by converting original color images to relative-color images. Relative-color images also helped minimize changes in color that occur due to changes in the photographic and digitization processes. Tumors in the relative-color images were segmented and morphologically filtered. Filtered, relative-color, tumor features were then extracted and various pattern-classification schemes were applied. Results: Experimentation resulted in four useful pattern classification methods, the best of which was an overall classification rate of 100% for melanoma and melanoma in situ (grouped) and 60% for Clark nevus. Conclusion: Melanoma and melanoma in situ have feature parameters and feature values that are similar enough to be considered one class of tumor that significantly differs from
7. A case report of primary cardiac myxofibrosarcoma presenting with severe congestive heart failure
OpenAIRE
Ujihira, Kosuke; Yamada, Akira; Nishioka, Naritomo; Iba, Yutaka; Maruyama, Ryushi; Nakanishi, Katsuhiko; Shimizu, Ai; Hatanaka, Kanako C.; Mitsuhashi, Tomoko; Shinohara, Toshiya; Ueda, Hatsue Ishibashi
2016-01-01
Background Primary cardiac sarcomas are extremely rare. Furthermore, the myxofibrosarcomas are one of the rarest forms of cardiac sarcomas, and its prognosis is known to be quite poor. Case presentation This is a case of a 23-year-old man who presented with acute severe congestive heart failure caused by almost complete obstruction of the mitral valve due to a large left atrial tumor. The patient required endotracheal intubation before his arrival to the hospital, and underwent an emergent su...
8. Electrical Stimulation Promotes Cardiac Differentiation of Human Induced Pluripotent Stem Cells
OpenAIRE
Damián Hernández; Rodney Millard; Priyadharshini Sivakumaran; Wong, Raymond C. B.; Crombie, Duncan E.; Hewitt, Alex W.; Helena Liang; Hung, Sandy S. C.; Alice Pébay; Shepherd, Robert K.; Gregory J Dusting; Lim, Shiang Y
2016-01-01
Background. Human induced pluripotent stem cells (iPSCs) are an attractive source of cardiomyocytes for cardiac repair and regeneration. In this study, we aim to determine whether acute electrical stimulation of human iPSCs can promote their differentiation to cardiomyocytes. Methods. Human iPSCs were differentiated to cardiac cells by forming embryoid bodies (EBs) for 5 days. EBs were then subjected to brief electrical stimulation and plated down for 14 days. Results. In iPS(Foreskin)-2 cell...
9. Experience of cardiac rehabilitation after coronary artery surgery: effects on health and risk factors
OpenAIRE
Lindsay, G.; Hanlon, W.P; Smith, L.N.; Belcher, P.R.
2003-01-01
Objective:Cardiac rehabilitation (CR) programs are provided to support the recovery process following acute myocardial infarction and coronary artery bypass grafting (CABG). Attendance varies. We related attendance following CABG to severity of cardiac symptoms, general health status (Short Form-36) and prevalence of modifiable coronary artery disease (CAD) risk factors. METHODS: 209 patients due to undergo CABG were recruited and assessed preoperatively as well as at a mean of 16.4 months po...
10. Detection and classification of cardiac ischemia using vectorcardiogram signal via neural network
OpenAIRE
2011-01-01
Background: Various techniques are used in diagnosing cardiac diseases. The electrocardiogram is one of these tools in common use. In this study vectorcardiogram (VCG) signals are used as a tool for detection of cardiac ischemia. Methods: VCG signals used in this study were obtained form 60 patients suspected to have ischemia disease and 10 normal candidates. Verification of the ischemia had done by the cardiologist during strain test by the evaluation of electrocardiogram (ECG) records ...
11. Random forest learning of ultrasonic statistical physics and object spaces for lesion detection in 2D sonomammography
Science.gov (United States)
Sheet, Debdoot; Karamalis, Athanasios; Kraft, Silvan; Noël, Peter B.; Vag, Tibor; Sadhu, Anup; Katouzian, Amin; Navab, Nassir; Chatterjee, Jyotirmoy; Ray, Ajoy K.
2013-03-01
Breast cancer is the most common form of cancer in women. Early diagnosis can significantly improve lifeexpectancy and allow different treatment options. Clinicians favor 2D ultrasonography for breast tissue abnormality screening due to high sensitivity and specificity compared to competing technologies. However, inter- and intra-observer variability in visual assessment and reporting of lesions often handicaps its performance. Existing Computer Assisted Diagnosis (CAD) systems though being able to detect solid lesions are often restricted in performance. These restrictions are inability to (1) detect lesion of multiple sizes and shapes, and (2) differentiate between hypo-echoic lesions from their posterior acoustic shadowing. In this work we present a completely automatic system for detection and segmentation of breast lesions in 2D ultrasound images. We employ random forests for learning of tissue specific primal to discriminate breast lesions from surrounding normal tissues. This enables it to detect lesions of multiple shapes and sizes, as well as discriminate between hypo-echoic lesion from associated posterior acoustic shadowing. The primal comprises of (i) multiscale estimated ultrasonic statistical physics and (ii) scale-space characteristics. The random forest learns lesion vs. background primal from a database of 2D ultrasound images with labeled lesions. For segmentation, the posterior probabilities of lesion pixels estimated by the learnt random forest are hard thresholded to provide a random walks segmentation stage with starting seeds. Our method achieves detection with 99.19% accuracy and segmentation with mean contour-to-contour error lesions.
12. Staged re-evaluation of non-culprit lesions in ST segment elevation myocardial infarction: a retrospective study
OpenAIRE
Thim, Troels; Egholm, Gro; Olesen, Kevin Kris Warnakula; Kaltoft, Anne; Terkelsen, Christian Juhl; Krusell, Lars Romer; Kristensen, Steen Dalby; Bøtker, Hans Erik; Christiansen, Evald Høj; Maeng, Michael
2016-01-01
Objective It remains unknown whether complete revascularisation is optimally performed in patients with ST segment elevation myocardial infarction (STEMI) during the index or at staged procedures. The aims of this study were to quantify the number of primary percutaneous coronary intervention (PCI) procedures in which non-culprit lesions needed further evaluation, to determine the consequence of the re-evaluation and to quantify adverse cardiac events during the waiting time for re-evaluation...
13. Imaging findings of various calvarial bone lesions witha focus on osteolytic lesions
Energy Technology Data Exchange (ETDEWEB)
Yim, Young Hee; Moon, Won Jin; An, Hyeong Su; Cho, Joon [Konkuk University Medical Center, Konkuk University School of Medicine, Seoul (Korea, Republic of); Rho, Myung Ho [Dept. of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)
2016-01-15
In this review, we present computed tomography (CT) and magnetic resonance imaging (MRI) findings of various calvarial lesions on the basis of their imaging patterns and list the differential diagnoses of the lesions. We retrospectively reviewed 256 cases of calvarial lesion (122 malignant neoplasms, 115 benign neoplasms, and 19 non-neoplastic lesions) seen in our institutions, and classified them into six categories based on the following imaging features: generalized skull thickening, focal skull thickening, generalized skull thinning, focal skull thinning, single lytic lesion, and multiple lytic lesions. Although bony lesions of the calvarium are easily identified on CT, bone marrow lesions are better visualized on MRI including diffusion-weighted imaging or fat-suppressed T2-weighted imaging. Careful interpretation of calvarial lesions based on pattern recognition can effectively narrow a range of possible diagnoses.
14. Characteristic findings in images of extra-pancreatic lesions associated with autoimmune pancreatitis
Energy Technology Data Exchange (ETDEWEB)
Fujinaga, Yasunari, E-mail: fujinaga@shinshu-u.ac.jp [Department of Radiology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621 (Japan); Kadoya, Masumi [Department of Radiology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621 (Japan); Kawa, Shigeyuki [Center of Health, Safety and Environmental Management, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621 (Japan); Hamano, Hideaki [Department of Medicine, Gastroenterology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621 (Japan); Ueda, Kazuhiko; Momose, Mitsuhiro; Kawakami, Satoshi; Yamazaki, Sachie; Hatta, Tomoko; Sugiyama, Yukiko [Department of Radiology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621 (Japan)
2010-11-15
Purpose: Autoimmune pancreatitis is a unique form of chronic pancreatitis characterized by a variety of extra-pancreatic involvements which are frequently misdiagnosed as lesions of corresponding organs. The purpose of this study was to clarify the diagnostic imaging features of extra-pancreatic lesions associated with autoimmune pancreatitis. Materials and methods: We retrospectively analyzed diagnostic images of 90 patients with autoimmune pancreatitis who underwent computer-assisted tomography, magnetic resonance imaging, and/or gallium-67 scintigraphy before steroid therapy was initiated. Results: AIP was frequently (92.2%) accompanied by a variety of extra-pancreatic lesions, including swelling of lachrymal and salivary gland lesions (47.5%), lung hilar lymphadenopathy (78.3%), a variety of lung lesions (51.2%), wall thickening of bile ducts (77.8%), peri-pancreatic or para-aortic lymphadenopathy (56.0%), retroperitoneal fibrosis (19.8%), a variety of renal lesions (14.4%), and mass lesions of the ligamentum teres (2.2%). Characteristic findings in CT and MRI included lymphadenopathies of the hilar, peri-pancreatic, and para-aortic regions; wall thickening of the bile duct; and soft tissue masses in the kidney, ureters, aorta, paravertebral region, ligamentum teres, and orbit. Conclusions: Recognition of the diagnostic features in the images of various involved organs will assist in the diagnosis of autoimmune pancreatitis and in differential diagnoses between autoimmune pancreatitis-associated extra-pancreatic lesions and lesions due to other pathologies.
15. Characterizing iron deposition in multiple sclerosis lesions using susceptibility weighted imaging
Science.gov (United States)
Haacke, E. Mark; Makki, Malek; Ge, Yulin; Maheshwari, Megha; Sehgal, Vivek; Hu, Jiani; Selvan, Madeswaran; Wu, Zhen; Latif, Zahid; Xuan, Yang; Khan, Omar; Garbern, James; Grossman, Robert I.
2009-01-01
Purpose To investigate whether the variable forms of putative iron deposition seen with susceptibility weighted imaging (SWI) will lead to a set of multiple sclerosis (MS) lesion characteristics different than that seen in conventional MR imaging. Materials and Methods Twenty-seven clinically definite MS patients underwent brain scans using magnetic resonance imaging including: pre- and post-contrast T1-weighted, T2-weighted, FLAIR, and SWI at 1.5T, 3T and 4T. MS lesions were identified separately in each imaging sequence. Lesions identified in SWI were re-evaluated for their iron content using the SWI filtered phase images. Results There were a variety of new lesion characteristics identified by SWI and these were classified into six types. A total of 75 lesions were seen only with conventional imaging, 143 only with SWI and 204 by both. From the iron quantification measurements, a moderate linear correlation between signal intensity and iron content (phase) was established. Conclusion The amount of iron deposition in the brain may serve as a surrogate biomarker for different MS lesion characteristics. SWI showed many lesions missed by conventional methods and six different lesion characteristics. SWI was particularly effective at recognizing the presence of iron in MS lesions and in the basal ganglia and pulvinar thalamus. PMID:19243035
16. Morphogenesis of the demyelinating lesions in Baló's concentric sclerosis.
Science.gov (United States)
Barz, Helmut; Barz, Ulrich; Schreiber, Almut
2016-06-01
In tissues with elastic properties, an edema causes a raised tissue pressure and therefore a diminished blood flow. The authors assume that an increased tissue pressure due to local and/or relapsing edema may be the cause for incomplete necrosis (e.g. demyelinated lesions) or seldom complete necrosis in the brain. Newly forming demyelinating lesions seldom show small tissue bands with normal appearing myelin sheaths in the immediate vicinity of precursor lesions (Baló type of MS). The small myelinated bands are the result of a "protected zone" on the edge of previous demyelinated lesions. The authors explain this protected zone with two arguments. Firstly, the resorptive granulation tissue of more or less older lesions is relatively rich in capillaries. These capillaries may act as an energy reservoir that can nourish not only the plaque, but also a narrow adjacent myelinated tissue band by diffusion, even if the capillary blood flow in this tissue band is limited due to the greater tissue pressure of a new developing lesion in the neighborhood. Secondly, another protective mechanism may act simultaneously: older or more sclerosed lesions and small adherent bands of myelinated tissue with them may swell less in cases of an edema than in normal tissue. The hardening of the older lesions is caused by proliferated fiber-forming astrocytes in the sense of scarring. In an area with an increased tissue pressure, the capillaries are less compressed in a sclerosed lesion than in regions of normal grey and white matter. In addition, the adherent myelinated tissue band closest to the edge of a hardened plaque is better protected against swelling and compression than the further away tissue. Theoretically, this protection zone is comparable with protected blood vessels in the Haversian canals or the medullary spaces of bones. Both theses of protecting mechanisms at the edges of demyelinated lesions support the assumption of a hypoxic causation principle of demyelinating
17. [Management of the meniscal lesion].
Science.gov (United States)
Baillon, B; Cermak, K; Vancabeke, M
2011-01-01
About 1,5 million arthroscopies are each year performed in the world, 50 % for meniscal affections. The menisci participate in the femoro-tibial load transmission and in the joint shock absorption; they contribute to the knee stability and play a role in the joint lubrication. The menisci are therefore important structures, and, in the case of a lesion, surgical abstention or repair should be favoured. When a meniscectomy has to be performed, it should be economical, preserving the meniscal wall. Meniscectomy is contra-indicated in the child and in the case of knee osteoarthrosis. Meniscal healing is compromised if the knee is unstable. If after total meniscectomy a patient presents symptomatic early osteoarthrosis, without marked loss of alignment, meniscal allografting is a therapeutic option, especially at the lateral compartment.
18. Anaesthetic management of patients with congenital heart disease presenting for non-cardiac surgery.
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Mohindra R
2002-01-01
Full Text Available The incidence of congenital heart disease is about one percent of all live births in the United States. Treatment is being performed at a younger age and these children are showing improved survival. It is not unusual for children with congenital heart disease to present for non-cardiac surgery. Their management depends on their age, type of lesion, extent of corrective procedure, the presence of complications and other congenital anomalies. Each patient needs a detailed pre-operative evaluation to understand the abnormal anatomy and physiology, and related anaesthetic implications. No anaesthetic agent is an absolute contraindication, although drugs beneficial for one lesion may be detrimental for another. Regional anaesthesia has also been safely used in children with congenital heart disease. However the anaesthesiologist must have a detailed understanding of the pathophysiology of the lesion and the pharmacology of drugs being used to be able to provide safe anaesthesia for children with congenital heart disease.
19. Radiographical resolution of renal lymphangiomatosis following cardiac transplantation.
Science.gov (United States)
Slater, Rick C; Iheagwara, Uzoma; Chen, Mang L
2014-04-01
Renal lymphangiomatosis is a disease characterized by abnormal formation of perirenal lymphatic vessels that fail to communicate with other retroperitoneal lymphatics; as a result, perirenal lymphatics dilate and form cysts. While typically an asymptomatic incidental finding, renal lymphangiomatosis rarely presents as flank or abdominal pain, ascites, impaired renal function, hypertension, hematuria, or proteinuria. Here we present the first known case of renal lymphangiomatosis found to spontaneously resolve following cardiac transplantation.
20. The anatomy of the cardiac veins in mice
Science.gov (United States)
Ciszek, Bogdan; Skubiszewska, Daria; Ratajska, Anna
2007-01-01
Although the cardiac coronary system in mice has been the studied in detail by many research laboratories, knowledge of the cardiac veins remains poor. This is because of the difficulty in marking the venous system with a technique that would allow visualization of these large vessels with thin walls. Here we present the visualization of the coronary venous system by perfusion of latex dye through the right caudal vein. Latex injected intravenously does not penetrate into the capillary system. Murine cardiac veins consist of several principal branches (with large diameters), the distal parts of which are located in the subepicardium. We have described the major branches of the left atrial veins, the vein of the left ventricle, the caudal veins, the vein of the right ventricle and the conal veins forming the conal venous circle or the prepulmonary conal venous arch running around the conus of the right ventricle. The venous system of the heart drains the blood to the coronary sinus (the left cranial caval vein) to the right atrium or to the right cranial caval vein. Systemic veins such as the left cranial caval, the right cranial caval and the caudal vein open to the right atrium. Knowledge of cardiac vein location may help to elucidate abnormal vein patterns in certain genetic malformations. PMID:17553104
1. Fabrication and characterization of bio-engineered cardiac pseudo tissues
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Xu Tao; Boland, Thomas [Department of Bioengineering, 420 Rhodes Hall, Clemson University, Clemson, SC 29634 (United States); Baicu, Catalin; Aho, Michael; Zile, Michael, E-mail: tboland@clemson.ed [Department of Medicine, Medical University of South Carolina, Charleston, SC 29425 (United States)
2009-09-15
We report on fabricating functional three-dimensional (3D) tissue constructs using an inkjet based bio-prototyping method. With the use of modified inkjet printers, contractile cardiac hybrids that exhibit the forms of the 3D rectangular sheet and even the 'half heart' (with two connected ventricles) have been fabricated by arranging alternate layers of biocompatible alginate hydrogels and mammalian cardiac cells according to pre-designed 3D patterns. In this study, primary feline adult and H1 cardiomyocytes were used as model cardiac cells. Alginate hydrogels with controlled micro-shell structures were built by spraying cross-linkers in micro-drops onto un-gelled alginic acid. The cells remained viable in constructs as thick as 1 cm due to the programmed porosity. Microscopic and macroscopic contractile functions of these cardiomyocyte constructs were observed in vitro. These results suggest that the inkjet bio-prototyping method could be used for hierarchical design of functional cardiac pseudo tissues, balanced with porosity for mass transport and structural support.
2. Cutaneous lesions in new born
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Sachdeva Meenakshi
2002-11-01
Full Text Available Five hundred unselected newborn babies delivered in the Department of Obstetrics and Gynaecology, Unit II of SGBT Hospital attached to Government Medical College, Amritsar during April 2000 to October 2000 were examined for cutaneous lesions daily for the first five days after birth. Different cutaneous lesions were seen in 474(94. 8% newborns. The physiological skin changes observed in order of frequency were Epstein pearls in 305(61%, Mongolian spot in 301(60. 2%, superficial cutaneous desquamation in 200(40%, icterus in 128(25. 6%, milia in 119(23. 8%, sebaceous gland hyperplasia in 107 (21. 4%, occipital alopecia in 94(18. 8%, lanugo in 72(14. 4%, peripheral cyanosis in 47(9. 4%, breast hypertrophy in 29(5. 8% and miniature puberty in 28(5. 6% newborns. Of the transient non-infective skin diseases, erythema toxicum neonatorum was observed most commonly in 105(21 %, followed by miliaria rubra in 103(20. 6% and acne neonatorum in 27(5. 4% newborns. The naevi and other developmental defects in the descending order were salmon patch in 69(13. 8%, congenital melanocytic noevi in 10(2%, accessory tragi in 3(0.6%, spina bifida in 2(0.4%, hydrocephalus in 1(0.2% and poliosis in 1(0.2% newborns. Cradle cap was the only dermatitis observed in 50(10% newborns. One (0.2% case each of Harlequin ichthyosis and labial cyst was seen.
3. Benign Lesions of The Vocal Fold
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Ozgur Surmelioglu
2013-02-01
Full Text Available Benign lesions of vocal folds are common disorders. Fifty percent of patients who have sound complaints are found to have these lesions after endoscopic and stroboscopic examinations. Benign vocal fold diseases are primarily caused by vibratory trauma. However they may also occur as a result of viral infections and congenital causes. These lesions are often presented with the complaints of dysphonia. [Archives Medical Review Journal 2013; 22(1.000: 86-95
4. Abnormal vulval lesions: diagnosis and management
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Aarti Kothari
2016-09-01
Full Text Available Vulval symptoms are commonly found and cause considerable distress for women. Symptoms are often chronic and can significantly affect the quality of womens lives including sexual function and wellbeing. Despite the frequency of vulval symptoms, women often find it difficult to seek medical advice due to multiple reasons, mostly cultural and emotional. This part is not easily self-observable neither are women aware of the fact that a vulvar lesion could also be a manifestation of a systemic disease. The idea behind this study was to identify whether presenting vulval lesion is dermatological or non-dermatological and to control the symptoms, to identify nature of the various vulvar lesions (inflammatory or neoplastic and to identify those skin lesions not responding to treatment which require biopsy and further management. It was a clinical descriptive study. Cases included women with vulvar lesions who attended Gynaec OPD at Dhiraj General Hospital affiliated to S.B.K.S. Medical Institute and Research Centre of Vadodara. After taking their informed consent ,all the women who had symptoms like vaginal discharge, itching or discomfort associated a with vulvar lesion, visible lesion or growth over vulva were thoroughly investigated to rule out any systemic illness causing vulvar lesion following which biopsy was taken if solid growth or a non-healing lesion was present. Treatment was done according to the lesions. In the presence of vulvar complains, a diagnostic pathway including systematic physical examination is always mandatory to detect SCC early. A non-healing lesion must be subjected to biopsy mandatorily. Women should be educated to avoid ODC drugs or creams when they face vulval lesions. [Int J Reprod Contracept Obstet Gynecol 2016; 5(9.000: 3242-3248
5. Management of Anal Squamous Intraepithelial Lesions
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Pineda, Carlos E.; Welton, Mark L.
2009-01-01
Anal squamous intraepithelial lesions include both low-grade squamous intraepithelial lesions (LSIL) and high-grade squamous intraepithelial lesions (HSIL) and are caused by chronic infection with the human papillomavirus (HPV). The disease is increasing in both incidence and prevalence, especially among patients with the following risk factors: homosexual men, acquired or iatrogenic immunosuppression, and presence of other HPV-related diseases. Although the natural history of the disease is ...
6. ATYPICAL BULLOUS PYODERMA GANGRENOSUM WITH EARLY LESIONS MIMICKING CHICKEN POX
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Ramesh
2013-10-01
Full Text Available ABSTRACT : Pyoderma Gangrenosum (PG rare neutrophilic dermatoses (1/100,00 0, of which Bullous Pyoderma gangrenosum is an atypical form, which is very rare. Bullous PG is usually associated with haematological disorders like myeloproliferative disorders, haematological malignancies specially AML and several other haematological disorders. It presents as a superficial haemorrhagic bulla which ulcerates, ulcers increase in size and heal with scarring. Treatment is mainly to identify and treat the cause. Pyoderma Gangrenosum shows rapid response to oral corticosteroid therapy. 1 , 3 . Clinical presentation: A 32yr old female presented with fever, multiple vesicles on face, upper limb, lower limb and trunk, and these early lesions looked like chicken pox lesions. Lesions increased in size to form haemorrhagic bullas which eroded to form ulcers, ulcers rapidly increased in size with necrotic base and erythematous to violaceous border. Investigation: Haemoglobin: 5.7gm%, Peripheral smear: normocytic and normochromic anaemia. Skin Biopsy: Sub corneal blisters with dermal and perifollicular n eutrophilic infiltrate. A diagnosis of Bullous Pyoderma gangrenosum was made. Patient’s anaemia was treated; oral prednisolone and topical steroids were started. Patient showed marked improvement to treatment.
7. Molecular and immunohistochemical analyses of cardiac troponin T during cardiac development in the Mexican axolotl, Ambystoma mexicanum.
Science.gov (United States)
Zhang, C; Pietras, K M; Sferrazza, G F; Jia, P; Athauda, G; Rueda-de-Leon, E; Rveda-de-Leon, E; Maier, J A; Dube, D K; Lemanski, S L; Lemanski, L F
2007-01-01
The Mexican axolotl, Ambystoma mexicanum, is an excellent animal model for studying heart development because it carries a naturally occurring recessive genetic mutation, designated gene c, for cardiac nonfunction. The double recessive mutants (c/c) fail to form organized myofibrils in the cardiac myoblasts resulting in hearts that fail to beat. Tropomyosin expression patterns have been studied in detail and show dramatically decreased expression in the hearts of homozygous mutant embryos. Because of the direct interaction between tropomyosin and troponin T (TnT), and the crucial functions of TnT in the regulation of striated muscle contraction, we have expanded our studies on this animal model to characterize the expression of the TnT gene in cardiac muscle throughout normal axolotl development as well as in mutant axolotls. In addition, we have succeeded in cloning the full-length cardiac troponin T (cTnT) cDNA from axolotl hearts. Confocal microscopy has shown a substantial, but reduced, expression of TnT protein in the mutant hearts when compared to normal during embryonic development.
8. Lesion localization in aphasia without hemiparesis
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Komatsu, Midori; Senoh, Yoko; Okamoto, Koichi; Morimatsu, Mitsunori; Hirai, Shunsaku (Gunma Univ., Maebashi (Japan). School of Medicine)
1983-06-01
The distribution of the lesions responsible for aphasia unassociated with right-sided hemiparesis was evaluated by cranial computed tomography (CT) among stroke patients. In the Broca aphasia group were observed atypical aphasic symptoms, and the lesions were far more localized than in ordinary Broca one. In the Wernicke aphasia group showed relatively large lesions in the left superior temporal gyrus, sometimes extending to supramarginal and angular gyri, which caused such additional symptoms as apraxia without motor paresis in some cases. In the Transcortical motor aphasia group showed the occlusion of the left internal carotid artery, though without obvious abnormality at CT. In another patient a circumscribed low density lesion was disclosed in the area anterior and superior to so-called Broca's area. In the Transcortical sensory aphasia group, the lesion involved the borderzone supplied by the left middle and posterior cerebral arteries. In the Amnestic aphasia group showed a lesion in the left parietal lobe, while in another no remarkable change was demonstrated. In the Global aphasia group, one had multiple isolated lesions in both anterior and posterior speech areas. Another showed a large lesion involving the whole territory of the left middle cerebral artery. In the remaining one a high density area was observed in the left superior temporal, supramarginal and angular gyri, not extending to the frontal lobe beyond with sylvian fissure. Therefore, in interpreting CTs of such aphasic patients we must take account of not only the extent of the lesion but also the severity of destruction.
9. Polypoid Lesions of the Gallbladder in Children
Science.gov (United States)
Beneck, Debra; Bostwick, Howard E.
1997-01-01
Polypoid lesions of the gallbladder in children are rare. We report a case of a gallbladder polyp in a 14-year-old boy who presented with recurrent right upper quadrant abdominal pain. Ultrasound examination of the abdomen revealed a polypoid lesion of the gallbladder. His symptoms resolved after laparoscopic cholecystectomy. Histological examination of the gallbladder demonstrated a benign adenomatous polyp. Although the experience with polypoid lesions of the gallbladder in children is limited, we currently recommend cholecystectomy because these lesions are associated with acalculous cholecystitis, and because their long-term effects are unknown. PMID:9876680
10. Nutritional Status and Cardiac Autophagy
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Jihyun Ahn
2013-02-01
Full Text Available Autophagy is necessary for the degradation of long-lasting proteins and nonfunctional organelles, and is activated to promote cellular survival. However, overactivation of autophagy may deplete essential molecules and organelles responsible for cellular survival. Lifelong calorie restriction by 40% has been shown to increase the cardiac expression of autophagic markers, which suggests that it may have a cardioprotective effect by decreasing oxidative damage brought on by aging and cardiovascular diseases. Although cardiac autophagy is critical to regulating protein quality and maintaining cellular function and survival, increased or excessive autophagy may have deleterious effects on the heart under some circumstances, including pressure overload-induced heart failure. The importance of autophagy has been shown in nutrient supply and preservation of energy in times of limitation, such as ischemia. Some studies have suggested that a transition from obesity to metabolic syndrome may involve progressive changes in myocardial inflammation, mitochondrial dysfunction, fibrosis, apoptosis, and myocardial autophagy.
11. [Cardiac support and replacement therapies].
Science.gov (United States)
Lotz, Christopher; Roewer, Norbert; Muellenbach, Ralf M
2016-09-01
Circulatory support represents an integral part within the treatment of the critically ill patient. Sophisticated pharmacologic regimens help to maintain systemic perfusion pressure by increasing vascular tone as well as mediating positive inotropic effects. Besides the administration of catecholamines and phosphodiesterase-III-inhibitors, in particular the administration of levosimendan represents a promising alternative during low-cardiac-output. Nevertheless, sufficient evidence demonstrating a survival benefit for any pharmacologic regimen is nonexistent. In case pharmacological measures do not suffice mechanical cardiopulmonary support (MCS) may be used. MCS may be used during cardiopulmonary resuscitation or a "low-cardiac-output-syndrome" as bridging towards decision, recovery or long-term support. Venoarterial extracorporeal membrane oxygenation (vaECMO) may take over cardiopulmonary function and may improve survival as well as neurological outcome after cardiogenic shock or cardiopulmonary resuscitation. PMID:27631451
12. Heart fields and cardiac morphogenesis.
Science.gov (United States)
Kelly, Robert G; Buckingham, Margaret E; Moorman, Antoon F
2014-10-01
In this review, we focus on two important steps in the formation of the embryonic heart: (i) the progressive addition of late differentiating progenitor cells from the second heart field that drives heart tube extension during looping morphogenesis, and (ii) the emergence of patterned proliferation within the embryonic myocardium that generates distinct cardiac chambers. During the transition between these steps, the major site of proliferation switches from progenitor cells outside the early heart to proliferation within the embryonic myocardium. The second heart field and ballooning morphogenesis concepts have major repercussions on our understanding of human heart development and disease. In particular, they provide a framework to dissect the origin of congenital heart defects and the regulation of myocardial proliferation and differentiation of relevance for cardiac repair.
13. Brain Embolism Secondary to Cardiac Myxoma in Fifteen Chinese Patients
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Youming Long
2014-01-01
Full Text Available Background. Heart myxoma-related embolisms commonly involve the central nervous system, but data are lacking in Chinese patients. Methods. 27 patients diagnosed with myxoma were reviewed retrospectively. Results. Among 27 patients, fourteen (51.9% patients were women. Fifteen (55.6% patients had brain embolisms. Rarely, patients were misdiagnosed with central nervous system vasculitis (n = 2, moyamoya disease (n = 1, and neuromyelitis optica (n = 1. We found positive associations between mRS (>3 and female gender (r = 0.873, P10 × 109/L (r = 0.722, P = 0.002, tumour size (r = 0.866, P0.05. Conclusions. Neurologic manifestations in Chinese patients with cardiac myxoma-related stroke were complicated and multifarious. Female gender, infection, other severe complications, low SBP, tumour size, bilateral brain lesions, TACI, and high WBC counts could be associated with a poor prognosis.
14. [INFLAMMATION AND CARDIAC INSUFFICIENCY ASSOCIATED WITH INFECTIOUS ENDOCARDITIS].
Science.gov (United States)
Fedorova, T A; Tazina, S Ya; Kaktursky, L V; Kanareitseva, T D; Stefanenko, N I; Burtsev, V I; Semenenko, N A
2016-01-01
The study included 62 patients with uncomplicated primary and secondary infectious endocarditis admitted to S.PBotkin city hospital from 2011 to 2014. The emphasis is laid on diagnostic significance of dynamic measurements of the levels of C-reactive protein, tumour necrosis factor and highly sensitive troponin-1 for the evaluation of activity of the infectious/toxic process, severity of the disease, and detection of complications. The study revealed the relationship of the enhanced level of troponin-1 with changes of inflammation markers, morphofunctional characteristics of myocardium, and circulatory failure. Morphologicl study demonstrated inflammatory and dystrophic changes in myocardium, focal and diffuse cardiofibrosis suggesting development of non-coronarogenic myocardial lesions that play an important role in the progress of cardiac failure associated with infectious endocarditis.
15. Cardiac Biomarkers in Hyperthyroid Cats
OpenAIRE
Sangster, J.K.; Panciera, D L; Abbott, J.A.; Zimmerman, K.C.; Lantis, A.C.
2013-01-01
Background Hyperthyroidism has substantial effects on the circulatory system. The cardiac biomarkers NT‐proBNP and troponin I (cTNI) have proven useful in identifying cats with myocardial disease but have not been extensively investigated in hyperthyroidism. Hypothesis Plasma NT‐proBNP and cTNI concentrations are higher in cats with primary myocardial disease than in cats with hyperthyroidism and higher in cats with hyperthyroidism than in healthy control cats. Animals Twenty‐three hyperthyro...
16. Historical perspectives of cardiac electrophysiology.
Science.gov (United States)
Lüderitz, Berndt
2009-01-01
The diagnosis and treatment of clinical electrophysiology has a long and fascinating history. From earliest times, no clinical symptom impressed the patient (and the physician) more than an irregular heart beat. Although ancient Chinese pulse theory laid the foundation for the study of arrhythmias and clinical electrophysiology in the 5th century BC, the most significant breakthrough in the identification and treatment of cardiac arrhythmias first occurred in this century. In the last decades, our knowledge of electrophysiology and pharmacology has increased exponentially. The enormous clinical significance of cardiac rhythm disturbances has favored these advances. On the one hand, patients live longer and thus are more likely to experience arrhythmias. On the other hand, circulatory problems of the cardiac vessels have increased enormously, and this has been identified as the primary cause of cardiac rhythm disorders. Coronary heart disease has become not just the most significant disease of all, based on the statistics for cause of death. Arrhythmias are the main complication of ischemic heart disease, and they have been directly linked to the frequently arrhythmogenic sudden death syndrome, which is now presumed to be an avoidable "electrical accident" of the heart. A retrospective look--often charming in its own right--may not only make it easier to sort through the copious details of this field and so become oriented in this universe of important and less important facts: it may also provide the observer with a chronological vantage point from which to view the subject. The study of clinical electrophysiology is no dry compendium of facts and figures, but rather a dynamic field of study evolving out of the competition between various ideas, intentions and theories. PMID:19196616
17. Cardiac Biomarkers and Cycling Race
OpenAIRE
Caroline Le Goff, Jean-François Kaux, Sébastien Goffaux, Etienne Cavalier
2015-01-01
In cycling as in other types of strenuous exercise, there exists a risk of sudden death. It is important both to understand its causes and to see if the behavior of certain biomarkers might highlight athletes at risk. Many reports describe changes in biomarkers after strenuous exercise (Nie et al., 2011), but interpreting these changes, and notably distinguishing normal physiological responses from pathological changes, is not easy. Here we have focused on the kinetics of different cardiac bi...
18. Functiogenesis of cardiac pacemaker activity.
Science.gov (United States)
Sakai, Tetsuro; Kamino, Kohtaro
2016-07-01
Throughout our investigations on the ontogenesis of the electrophysiological events in early embryonic chick hearts, using optical techniques to record membrane potential probed with voltage-sensitive dyes, we have introduced a novel concept of "functiogenesis" corresponding to "morphogenesis". This article gives an account of the framework of "functiogenesis", focusing on the cardiac pacemaker function and the functional organization of the pacemaking area. PMID:26719289
19. Cardiac involvement in tuberous sclerosis.
OpenAIRE
Mühler, E G; Turniski-Harder, V; Engelhardt, W.; von Bernuth, G
1994-01-01
OBJECTIVE--To assess the incidence, importance, and history of cardiac involvement in infants and children with tuberous sclerosis. DESIGN--Prospective study; clinical examination, sector and Doppler echocardiography, standard and ambulatory electrocardiography. SETTING--A tertiary referral centre. PATIENTS--21 patients with tuberous sclerosis aged 1 day to 16 years (mean 6.3 years); follow up investigations were available in 14 cases (10 retrospective, 4 prospective; mean follow up 4.3 years...
20. Praxial disorders in focal lesions of cerebral hemispheres
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Jorge Murillo Duran
2007-11-01
Full Text Available The purpose of this work is to analyze paraxial difficulties i.e, functional disorders in movementresulting from cerebral tissue lesions. In accordance with the literature on the subject, the following definition, the following definition of apraxia has been accepted: “Apraxia is inability in properly executing kinetic tasks without impairment or loss of motor or sensory functions or ataxia with would condition such inability”. “Proper execution” used in this definition concerns not only the effect of the action but also means of its realization. “Kinetic tasks” signify all aspects of motor activity defined by instructions, irrespective of the type of instruction (verbal or gestures, and regardless of whether it required −in the final effect− imitating the movement of the investigator or whether they were performed independently. The methodology has been based in the principle on Luria’s works.Deliberations on praxial disorders were based on investigation results embracing 90 patients with focal cerebral lesions. In fifty cases, changes were localized in the left cerebral hemisphere, in forty cases−in the right hemisphere. The summing up the results concerning a global comparison between cerebral hemispheres, indicate the following regularities: Results achieved made it possible to form the opinion that not all of the generally accepted tests investigating praxia in persons with cerebral lesions are solved faultlessly by healthy individuals; thus, a faulty execution should not always be regarded as a sign of pathological functioning of the cerebral tissue as a result of lesion.
1. Clinical-histopathological concordance in head and neck lesions.
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Sahily Espino Otero
2009-03-01
Full Text Available Background: Clinical-histopathological data contributes to a better diagnosis, assessment and treatment of head and neck lesions. Objective: To determine clinical-histopathological correlation of head and neck lesions. Methods: a descriptive, retrospective, observational study was developed in a series of cases (360 patients to determine the clinical diagnostic scope in relation to the histopathological techniques used in the Maxillary Surgery Service of “Gustavo Aldereguía Lima” hospital between June 2006 and 2007. Required data was taken from clinical histories and records from Pathological Anatomy, which were transferred to a form design for that purpose. Results: The age group of 0-19 years had the higher concordance among the studied groups (72,4%. 59, 7% of the studied cases had clinical-histopathological concordance, mainly in extra-oral lesions (60, 4% particularly in the vermilion border (82, 4 % and among the intra-oral the most common were those in the vestibular duct (100%. The most important lesions where clinical diagnosis did not coincide with histopathological diagnosis were fibroma with 23 in the intra-oral and warts and a total of 34 in extra-oral, followed by basal carcinomas. Conclusions: There is a significant correlation between clinical and histopathological diagnosis, suggesting high attention quality and correct application of the clinical method as central element in patients’ management.
2. Brain lesion induced by 1319nm laser radiation
Science.gov (United States)
Yang, Zaifu; Chen, Hongxia; Wang, Jiarui; Chen, Peng; Ma, Ping; Qian, Huanwen
2010-11-01
The laser-tissue interaction has not been well defined at the 1319 nm wavelength for brain exposure. The goal of this research effort was to identify the behavioral and histological changes of brain lesion induced by 1319 nm laser. The experiment was performed on China Kunming mice. Unilateral brain lesions were created with a continuous-wave Nd:YAG laser (1319nm). The brain lesions were identified through behavioral observation and histological haematoxylin and eosin (H&E) staining method. The behavior change was observed for a radiant exposure range of 97~773 J/cm2. The histology of the recovery process was identified for radiant exposure of 580 J/cm2. Subjects were sacrificed 1 hour, 1 week, 2 weeks, 3 months, 7 months and 13 months after laser irradiation. Results showed that after laser exposure, behavioral deficits, including kyphosis, tail entasia, or whole body paralysis could be noted right after the animals recovered from anesthesia while gradually disappeared within several days and never recurred again. Histologically, the laser lesion showed a typical architecture dependent on the interval following laser treatment. The central zone of coagulation necrosis is not apparent right after exposure but becomes obvious within several days. The nerotic tissue though may persist for a long time, will finally be completely resorbed. No carbonization granules formed under our exposure condition.
3. Histopathological study of healing in periapical lesions following endodontic treatments
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A. Khayat
1987-08-01
Full Text Available This study was perfomed on twenty five teeth which showed radiographic lesions( 6mm over 25 mm. the teeth were arranged in seven different groups and root canal therapy ( by warm Gutta-percha technique as surgical intervention were performed at various time intervals. In this investigation, histologic studies of the periapical tissues begin shortly after elimination of the root canal system with or without root canal obturation. This healing demonstrated with a replacement of granulation tissue by connective tissue, inflammatory cells diminish in number and densityb fibroblastic activity and their differentiation of osteoblastc osteoblastic activity forming osteoid and trabecular bone. The newly formed trabeculae extend from the periphery of the lesion to the center and root surfacesd nonorganized periodontal ligament fibers return to their original orientation soon after the newly formed trabeculae reach the apical root surface and form lamina duraInflammatory responses may continue simultaneously with periapical tissue regeneration and bone formation. Chronic inflammatory cells seem to be present occasionally in marrow spaces of the newly formed bone. Cellular activity and bone formation are demonstrated in the presence of the lining epithelium. This is seen between newly formed bone and apical root tip and might be suggestive of healing of the periapical cyst.
4. Sudden cardiac death risk stratification.
Science.gov (United States)
Deyell, Marc W; Krahn, Andrew D; Goldberger, Jeffrey J
2015-06-01
Arrhythmic sudden cardiac death (SCD) may be caused by ventricular tachycardia/fibrillation or pulseless electric activity/asystole. Effective risk stratification to identify patients at risk of arrhythmic SCD is essential for targeting our healthcare and research resources to tackle this important public health issue. Although our understanding of SCD because of pulseless electric activity/asystole is growing, the overwhelming majority of research in risk stratification has focused on SCD-ventricular tachycardia/ventricular fibrillation. This review focuses on existing and novel risk stratification tools for SCD-ventricular tachycardia/ventricular fibrillation. For patients with left ventricular dysfunction or myocardial infarction, advances in imaging, measures of cardiac autonomic function, and measures of repolarization have shown considerable promise in refining risk. Yet the majority of SCD-ventricular tachycardia/ventricular fibrillation occurs in patients without known cardiac disease. Biomarkers and novel imaging techniques may provide further risk stratification in the general population beyond traditional risk stratification for coronary artery disease alone. Despite these advances, significant challenges in risk stratification remain that must be overcome before a meaningful impact on SCD can be realized.
5. Review Article of Cardiac Amyloidosis
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Jittiporn PURATTANAMAL
2010-06-01
Full Text Available Cardiac amyloidosis is a term that means the deposit of abnormal proteins in the myocardium leading to global thickening of the heart walls. The clinical character is that of infiltrative cardiomyopathy. AL amyloidosis is the most common type that involves cardiac failure. Cardiac amyloid precedes clinical congestive heart failure, especially right-sided heart failure. Laboratory investigations have identified the amyloid fibril proteins deposited in the organ tissues. Immunofixation tests are the most sensitive that recognize the paraprotein mean light chain protein or immunoglobulin subtype deposit. Prognosis is poor if AL amyloidosis is untreated. Treatment of systemic involvement in AL amyloidosis is via chemotherapy such as melphalan and prednisolone. UK experts have reported the results of treatment in AL amyloidosis. Regardless of the use of adjunctive chemotherapy, the five-year survival after heart transplantation was generally poorer for AL (20 % at five years, but similar for non-AL amyloidosis (64 % at five years, than heart transplants in other cases. Progression of the systemic disease contributed to increased mortality. A specific treatment that increases the chances of survival is unknown.
6. Cardiac MRI in restrictive cardiomyopathy
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Gupta, A. [Department of Cardiovascular Radiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India); Singh Gulati, G., E-mail: gulatigurpreet@rediffmail.com [Department of Cardiovascular Radiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India); Seth, S. [Department of Cardiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India); Sharma, S. [Department of Cardiovascular Radiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India)
2012-02-15
Restrictive cardiomyopathy (RCM) is a specific group of heart muscle disorders characterized by inadequate ventricular relaxation during diastole. This leads to diastolic dysfunction with relative preservation of systolic function. Although short axis systolic function is usually preserved in RCM, the long axis systolic function may be severely impaired. Confirmation of diagnosis and information regarding aetiology, extent of myocardial damage, and response to treatment requires imaging. Importantly, differentiation from constrictive pericarditis (CCP) is needed, as only the latter is managed surgically. Echocardiography is the initial cardiac imaging technique but cannot reliably suggest a tissue diagnosis; although recent advances, especially tissue Doppler imaging and spectral tracking, have improved its ability to differentiate RCM from CCP. Cardiac catheterization is the reference standard, but is invasive, two-dimensional, and does not aid myocardial characterization. Cardiac magnetic resonance (CMR) is a versatile technique providing anatomical, morphological and functional information. In recent years, it has been shown to provide important information regarding disease mechanisms, and also been found useful to guide treatment, assess its outcome and predict patient prognosis. This review describes the CMR features of RCM, appearances in various diseases, its overall role in patient management, and how it compares with other imaging techniques.
7. Gastrointestinal Polypoid Lesions: The Albanian Reality
Directory of Open Access Journals (Sweden)
Gentiana Cekodhima
2015-12-01
Full Text Available Background: Gastrointestinal polypoid lesions are a well-known cause of possible future malignant lesions. Screening for these lesions, especially for colon polyps, has reduced morbidity and mortality from malignant tumors. To our best knowledge, no screening program on gastrointestinal polypoid lesions exists in Albania and no former study has been performed to check the distribution of these lesions. Therefore, our aim was to study the distribution of gastrointestinal polypoid lesions in a symptomatic outpatient population. Methods: This study included five hundred seventy five consecutive patients referred to perform an endoscopic examination, regardless of their specific complains and of their possible diagnosis, to one of the two Endoscopy Centers in Tirana in the period between January 1st 2008 and December 31st 2013. At least one polyp was resected and histologically examined in all included patients. Results: A total of 575 patients, of which 345 males (60.0%, aged 51.9 years (standard deviation 16.97 years, were examined and their data inserted in the statistical analysis. In total, 88 cases were identified with malignant pathologies of which 50 cases (56.8% were males. No case of malignancy was diagnosed among the nine esophageal specimens, but among the specimens resected from the stomach, small intestine and large intestine, were respectively diagnosed 21 (20.0%, 9 (40.9% and 58 (13.2% malignant lesions. Patients with malignant lesions were older (57.4 ± 16.8 years old in contrast to those with benign lesions (50.5 ± 17.0 years old (p = 0.004. Conclusion: Our study is the first one to offer figures on the polypoid lesions distribution and characteristics in the Albanian population. Large intestine is the main site where such lesions occur, but anyhow the small intestine presented a larger proportion of malignancy.
8. Consequences of cardiac myocyte-specific ablation of KATP channels in transgenic mice expressing dominant negative Kir6 subunits
OpenAIRE
Tong, XiaoYong; Porter, Lisa M.; Liu, GongXin; Dhar-Chowdhury, Piyali; Srivastava, Shekhar; Pountney, David J.; Yoshida, Hidetada; Artman, Michael; Fishman, Glenn I.; Yu, Cindy; Iyer, Ramesh; Morley, Gregory E.; Gutstein, David E.; Coetzee, William A.
2006-01-01
Consequences of cardiac myocyte-specific ablation of KATP channels in transgenic mice expressing dominant negative Kir6 subunits. Am J Physiol Heart Circ Physiol 291: H543–H551, 2006. First published February 24, 2006; doi:10.1152/ajpheart.00051.2006.—Cardiac ATP-sensitive K+ (KATP) channels are formed by Kir6.2 and SUR2A subunits. We produced transgenic mice that express dominant negative Kir6.x pore-forming subunits (Kir6.1-AAA or Kir6.2-AAA) in cardiac myocytes by driving their expression ...
9. Characteristics of in-hospital cardiac arrest and cardiopulmonary resuscitation
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Josip Ivić
2009-02-01
Full Text Available Aim We have studied epidemiology of in-hospital cardiac arrest, characteristics of organizing a reanimationand its,procedures as well as its documenting.Methods We analyzed all resuscitation procedure data where anesthesiology reanimation teams (RT providedcardiopulmonary resuscitation (CPR during one-year period. We included resuscitation attemptsthat were initiated outside the Department of Anesthesiology, excluding incidents in operation rooms andIntensive Care Unit (ICU. Data on every cardiac arrest and CPR were entered in a special form.Results During one-year period 87 CPR were performed. Victims of cardiac arrest were principallyelderly patients (age 60 – 80, mostly male (60%. Most frequent victims were neurological patients(42%, surgical patients (21% and neurosurgical patients (10%. The leading cause of cardiac arrestwas primary heart disease, following neurological diseases and respiration disorders of severe etiology.In over 90% cases CPR was initiated by medical personnel in their respective departments, RT arrivedwithin 5 minutes in 73,56% cases. Initially survival was 32%, but full recovery was accomplished in 4patients out of 87 (4,6%.Conclusion Victims of cardiac arrest are patients whose primary disease contributes to occurrence ofcardiorespiratory complications. High mortality and low percentage of full recovery can be explainedby characteristics of patients (old age, nature and seriousness of primary disease which significantly affectthe outcome of CPR. In some cases a question is raised whether to initiate the CPR at all. We wouldlike to point out that continous monitoring of potentially critical patients may prevent cardiorespiratoryincidents whereas the quality and success of CPR may be improved by training of staff and better technicalequipment on the relevant locations in the in the hospital where such incidents usually occur.
10. Noninvasive Fractional Flow Reserve for the Diagnosis of Lesion-specific Ischemia: A Case Example
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Jesper Møller Jensen
2015-01-01
Full Text Available A physically active 52-year-old male with atypical chest pain was referred to our department. A coronary computed tomography angiography (CCTA showed a stenotic plaque in the mid left anterior descending coronary artery (LAD. A rest-stress Rubidium-82 myocardial perfusion was normal. One year later the patient sustained a cardiac arrest and percutaneous coronary intervention of the mid-LAD was successfully performed. The original CCTA data were submitted for noninvasive determination of fractional flow reserve (FFR CT revealing an ischemia-producing lesion in the mid-LAD. This case demonstrates the inherent limitations of assessing lesion-specific ischemia. FFR CT shows promise as a new method for future selection of patients for coronary angiography.
11. Modulatory effect of semelil (ANGIPARS™) on isoproterenol induced cardiac injury.
Science.gov (United States)
Joukar, Siyavash; Najafipour, Hamid; Mirzaeipour, Fateme; Nasri, Hamidreza; Ahmadi, Mahboubeh Yeganeh Haj; Badinloo, Marziyeh
2013-01-01
Administration of semelil (ANGIPARS™) has been successful in the treatment of diabetic foot ulcer. Considering the improvement of blood flow and anti-inflammatory effect that are attributed to this drug, we investigated its effect on cardiovascular performance in rabbits with isoproterenol (ISO) induced myocardial injury. Animal groups included: control group; ISO group, received ISO 50 mg/kg s.c. for two consecutive days; S1+ISO, S5+ISO and S10+ISO groups, received semelil 1, 5, and 10 mg/kg/day i.p. respectively, 30 min before ISO. On the 3(rd) day, electrocardiogram (ECG) and hemodynamic parameters were recorded; blood samples were taken and hearts were removed for lab investigations. ISO induced heart injury, ECG disturbance, raise of cardiac troponin I and significant decrease in LVSP (p<0.05), +dp/dt max (p<0.01), -dp/dt max (p<0.05) along with increase of LVEDP (p<0.01). Semelil had no significant effects on ECG and plasma cardiac troponin I. Impairment of +dp/dt max and -dp/dt max was significantly improved in S5+ISO and S10+ISO groups (P<0.05 versus ISO). In addition, LVSP and LVEDP was somewhat recovered in these groups, although semelil (1 mg/kg/day) to some extent exacerbated the myocardial lesions induced by ISO (P<0.05). Therefore, in stressful conditions, semelil may improve myocardial contractility; however, it may aggravate the severity of injury. PMID:26417221
Institute of Scientific and Technical Information of China (English)
Yu-Sheng Lin; Shih-Ming Jung; Feng-Chun Tsai; Chun-Nan Yeh; Tzu-Fang Shiu; Hsueh-Hua Wu; Pyng-Jing Lin; Pao-Hsien Chu
2007-01-01
AIM: To investigate the clinical and pathologic findings,and to discuss the pathophysiology of hepatocellular carcinoma with cardiac metastasis.METHODS: Eight hepatoma patients with cardiac metastasis, who were treated by surgical excision from 1993 to 2006, were retrospectively studied. Detailed clinical parameters were analyzed.RESULTS: Of those eight patients, two (25%) were women and six (75%) were men, with the mean age of 50 years (range, 40-70 years). The presentations included: asymptomatic (75%), heart failure (25%), and pulmonary embolism (12.5%). All lesions involved the right atrium, and extended to the lung (12.5%), inferior vena cava (25%), and left atrium (12.5%). The level of tumor marker, alpha-fetal protein, was not correlated with the severity of metastasis or disease prognosis.Moreover, the availably estimated doubling time was less than 3 mo. The pathological findings included variable hemorrhage and necrosis. The survival time following surgery also varied from one month to more than 30 mo.CONCLUSION: Hepatoma metastasis to the heart was detected in all eight patients. This study demonstrates that surgery might help the outcome in such cases.
13. Angiomatous lesion and delayed cyst formation after gamma knife surgery for intracranial meningioma: case report and review of literatures
OpenAIRE
Liu, Zhiyong; He, Min; Chen, Hongxu; Liu, Yi; Li, Qiang; Li, Lin; Li, Jin; Chen, Haifeng; Xu, Jianguo
2015-01-01
Gamma Knife has become a major therapeutic method for intracranial meningiomas, vascular malformations and schwannomas with exact effect. In recent years an increasing number of delayed complications after Gamma Knife surgery have been reported, such as secondary tumors, cystic changes or cyst formation. But angiomatous lesion and delayed cyst formation after Gamma Knife for intracranial lesion has rarely been reported. Here we report the first case of angiomatous lesion and delayed cyst form...
14. Sudden death of cardiac origin and psychotropic drugs
Directory of Open Access Journals (Sweden)
2012-05-01
Full Text Available Mortality rate is high in psychiatric patients versus general population. An important cause of this increased mortality is sudden cardiac death (SCD as a major side-effect of psychotropic drugs. These SCDs generally result from arrhythmias occurring when the posology is high and may attain a toxic threshold but also at dosages within therapeutic range, in the presence of risk factors. There are three kinds of risk factors: physiological (e.g.: low cardiac rate of sportsmen, physiopathological (e.g.: hepatic insufficiency, hypothyroidism and "therapeutic" (due to interactions between psychotropic drugs and other medicines. Association of pharmacological agents may increase the likelihood of SCDs either by i a pharmacokinetic mechanism (e.g.: increased torsadogenic potential of a psychotropic drug when its destruction and/or elimination are compromised or ii a pharmacodynamical mechanism (e.g.: mutual potentiation of proarrhythmic properties of two drugs. In addition, some psychotropic drugs may induce sudden death in cases of pre-existing congenital cardiopathies such as i congenital long QT syndrome, predisposing to torsade de pointes that eventually cause syncope and sudden death. ii a Brugada syndrome, that may directly cause ventricular fibrillation due to reduced sodium current through Nav1.5 channels. Moreover, psychotropic drugs may be a direct cause of cardiac lesions also leading to SCD. This is the case, for example, of phenothiazines responsible for ischemic coronaropathies and of clozapine that is involved in the occurrence of myocarditis. The aims of this work are to delineate: i the risk of SCD related to the use of psychotropic drugs; ii mechanisms involved in the occurrence of such SCD; iii preventive actions of psychotropic drugs side effects, on the basis of the knowledge of patient-specific risk factors, documented from clinical history, ionic balance and ECG investigation by the psychiatrist.
15. 右心房血管肉瘤1例与心电门腔CT%Right atrial angiosarcoma and electrocardiogram-gated cardiac computed tomography: a case report
Institute of Scientific and Technical Information of China (English)
Jing Gong; Jianming Tian; Yi Xiao
2009-01-01
Primary cardiac tumors are quite rare and most of these tumors are benign. In this report, a patient presented with chest distress and shortness of breath after activity. Echocardiography of other hospital showed a hyperechoic right atrial mass. Electrocerdiogram-gated cardiac computed tomography (ECG-Gated CT) of our hospital provided accurate information about the site and extent of the tumor, and the involvement of neighboring structures, even about the malignant nature of the lesion. The pathological study indicated angiosarcorna. The role of ECG-Gated CT in the assessment of cardiac masses and tumors was discussed. Cardiac tumors are extremely rare and can be divided into benign and malignant lesions. Myxomas are the most common type of cardiac benign tumor, while angiosarcomas are the most common type of cardiac malignant tumor.Imaging studies play an important role in the diagnosis of cardiac angiosarcomas. Echocardiogram, computed tomography (CT) and magnetic resonance imaging (MRI) are the most common imaging studies for tumors evaluation. However, the precise tumor location is often difficult to evaluate precisely on the basis of two-dimensional source images. We conducted ECG-gated cardiac CT examination with 3D reconstruction for preoperative assessment in a patient with a angiosarcorna arising in the right atrium.
16. Evaluation of Known or Suspected Cardiac Sarcoidosis.
Science.gov (United States)
Blankstein, Ron; Waller, Alfonso H
2016-03-01
Sarcoidosis is a multisystem disorder of unknown cause, and cardiac sarcoidosis affects at least 25% of patients and accounts for substantial mortality and morbidity from this disease. Cardiac sarcoidosis may present with heart failure, left ventricular systolic dysfunction, AV block, atrial or ventricular arrhythmias, and sudden cardiac death. Cardiac involvement can be challenging to detect and diagnose because of the focal nature of the disease, as well as the fact that clinical criteria have limited diagnostic accuracy. Nevertheless, the diagnosis of cardiac sarcoidosis can be enhanced by integrating both clinical and imaging findings. This article reviews the various roles that different imaging modalities provide in the evaluation and management of patients with known or suspected cardiac sarcoidosis. PMID:26926267
17. [Asterixis in focal brain lesions].
Science.gov (United States)
Velasco, F; Gomez, J C; Zarranz, J J; Lambarri, I; Ugalde, J
2004-05-01
Asterixis is a motor control disorder characterized by the presence of abnormal movements of the lower limbs in the vertical plane during posture maintenance. Asterixis is usually bilateral and associated with toxic-metabolic metabolic encephalopathies. Unilateral asterixis is less frequent and it normally indicates focal brain damage. We report the cases of four patients (two males/two females), aged 57 to 83 years, suffering from uni or bilateral asterixis associated with focal brain damage. All patients underwent CT brain scan and a neurophysiological study (parietal EMG and/or PES). In addition, any toxic-metabolic cause that could be produced by this clinical phenomenon was ruled out with the appropriate testing. Unilateral asterixis is a clinical symptom that may indicate the presence of focal brain damage. Often, it is ignored or overlooked during routine neurological examinations. On the other hand, the presence of a bilateral asterixis is not always indicative of a toxic-metabolic encephalopathy.Rarely, such as in one of the cases herein presented, bilateral asterixis can also appear associated with structural brain lesions. Although asterixis diagnosis is fundamentally clinical, the neurophysiological study contributes to verify the diagnosis.
18. Cerebral CT of ischaemic lesions
Energy Technology Data Exchange (ETDEWEB)
Aulich, A.
1981-11-25
The diagnosis of stroke must first be established by clinical examination. CT has proved useful for confirmation of the diagnosis and provides a global intracranial picture of morphological changes in cerebral vascular diseases. A hemorrhage can be recognized with certainty at the first CT examination as the cause of the stroke, but in the detection of a lesion due to ischemia an important role is played by the correct choice of the time of examination, and in some cases also of the check-up with contrast medium. The differential diagnosis between infarct in the acute stage and encephalitis or gliomas of low-grade malignity can be difficult. A decision can often only be made after a series of examinations. Postmalacial conditions are often difficult to differentiate from defects due to other causes, such as hemorrhage, head injury, postoperative states and after encephalitis. A knowledge of the anamnesis and the clinical findings is indispensable for CT evaluation. In assessing the prognosis before vascular surgery on the extracranial brain-supplying vessels the performance of a CT examination should be advised. A warning is given against the use of CT as a screening method.
19. Sensing Cardiac Electrical Activity With a Cardiac Myocyte--Targeted Optogenetic Voltage Indicator
NARCIS (Netherlands)
Chang Liao, Mei-Ling; de Boer, Teun P; Mutoh, Hiroki; Raad, Nour; Richter, Claudia; Wagner, Eva; Downie, Bryan R; Unsöld, Bernhard; Arooj, Iqra; Streckfuss-Bömeke, Katrin; Döker, Stephan; Luther, Stefan; Guan, Kaomei; Wagner, Stefan; Lehnart, Stephan E; Maier, Lars S; Stühmer, Walter; Wettwer, Erich; van Veen, Toon; Morlock, Michael M; Knöpfel, Thomas; Zimmermann, Wolfram-Hubertus
2015-01-01
RATIONALE: Monitoring and controlling cardiac myocyte activity with optogenetic tools offer exciting possibilities for fundamental and translational cardiovascular research. Genetically encoded voltage indicators may be particularly attractive for minimal invasive and repeated assessments of cardiac
20. Spindle cell melanocytic lesions: part II--an approach to intradermal proliferations and horizontally oriented lesions.
Science.gov (United States)
Sade, Shachar; Al Habeeb, Ayman; Ghazarian, Danny
2010-05-01
Melanocytic lesions show great morphological diversity in their architecture and the cytomorphological appearance of their composite cells. Whereas functional melanocytes show a dendritic cytomorphology and territorial isolation, lesional nevomelanocytes and melanoma cells typically show epithelioid, spindled or mixed cytomorphologies, and a range of architectural arrangements. Spindling is common to melanocytic lesions, and may either be a characteristic feature or a divergent appearance. The presence of spindle cells may mask the melanocytic nature of a lesion, and is often disconcerting, either due to its infrequent appearance in a particular lesion or its interpretation as a dedifferentiated phenotype. Spindle cell melanocytic lesions follow the full spectrum of potential biological outcomes, and difficulty may be experienced judging the nature of a lesion due to a lack of consistently reliable features to predict biological behaviour. Over time, recognition of numerous histomorphological features that may portend a more aggressive lesion have been identified; however, the translation of these features into a diagnostic entity requires a gestalt approach. Although most spindle cell melanocytic lesions may reliably be resolved through this standard approach, problem areas do exist for the surgical pathologist or dermatopathologist. With this review (part II of II), we complete our discussion of spindle cell melanocytic lesions, in order to: (1) model a systematic approach to such lesions; and (2) provide familiarity with those melanocytic lesions which either typically or occasionally display a spindled cytomorphology.
1. Imaging granulomatous lesions with optical coherence tomography
DEFF Research Database (Denmark)
Banzhaf, Christina; Jemec, Gregor B E
2012-01-01
To investigate and compare the presentation of granulomatous lesions in optical coherence tomography (OCT) images and compare this to previous studies of nonmelanoma skin tumors.......To investigate and compare the presentation of granulomatous lesions in optical coherence tomography (OCT) images and compare this to previous studies of nonmelanoma skin tumors....
2. Elementary lesions in dermatological semiology: literature review*
Science.gov (United States)
Cardili, Renata Nahas; Roselino, Ana Maria
2016-01-01
Discrepancies in the terminology of elementary lesions persist when texts from Dermatology and Semiology books are compared, which can cause some confusion in both the teaching of undergraduate medical students and the learning acquired by professionals in the field. This review aims to compare and clarify the differences in the description of elementary lesions by many authors, used as references for specialists in dermatology.
3. The Post-Ureteroscopic Lesion Scale (PULS)
DEFF Research Database (Denmark)
Schoenthaler, Martin; Buchholz, Noor; Farin, Erik;
2014-01-01
The Post-Ureteroscopic Lesion Scale (PULS) offers a simple grading system for the description of ureteral lesions after ureteroscopy. In this article, we present the results of a video-based multicenter evaluation of the inter-rater reliability of clinically important PULS grades 0-3....
4. Principal component analysis of psoriasis lesions images
DEFF Research Database (Denmark)
Maletti, Gabriela Mariel; Ersbøll, Bjarne Kjær
2003-01-01
A set of RGB images of psoriasis lesions is used. By visual examination of these images, there seem to be no common pattern that could be used to find and align the lesions within and between sessions. It is expected that the principal components of the original images could be useful during future...
5. Common oral lesions associated with HIV infection.
Science.gov (United States)
Navazesh, M; Lucatorto, F
1993-09-01
More than 40 different lesions involving head and neck areas have been associated with HIV infection. The oral cavity may manifest the first sign of HIV infection. Early detection of these conditions can lead to early diagnosis of HIV infection and subsequent appropriate management. Signs, symptoms and management of the most common HIV-associated oral lesions are discussed.
6. Methods in pharmacology: measurement of cardiac output
OpenAIRE
Geerts, Bart F; Aarts, Leon P; Jansen, Jos R.
2011-01-01
Many methods of cardiac output measurement have been developed, but the number of methods useful for human pharmacological studies is limited. The ‘holy grail’ for the measurement of cardiac output would be a method that is accurate, precise, operator independent, fast responding, non-invasive, continuous, easy to use, cheap and safe. This method does not exist today. In this review on cardiac output methods used in pharmacology, the Fick principle, indicator dilution techniques, arterial pul...
7. Cardiac tumours simulating collagen vascular disease.
OpenAIRE
Fitzpatrick, A. P.; Lanham, J. G.; Doyle, D V
1986-01-01
Cardiac tumours can mimic collagen vascular disease and they are often accompanied by profound systemic upset. Both benign and malignant tumours may present in this way. Three cases of cardiac tumour, two malignant and one benign, are reported with just such a presentation. A review of fifteen similar case reports showed that a spectrum of different collagen vascular diseases was diagnosed and treated before the true diagnosis emerged. In half of these cases the cardiac tumour was only diagno...
8. Disseminated cysticercosis with pulmonary and cardiac involvement
OpenAIRE
Jain Bharat; Sankhe Shilpa; Agrawal Mukta; Naphade Prashant
2010-01-01
Pulmonary and cardiac involvement by cysticercosis is extremely rare, and is usually asymptomatic. We report the case of a 19-year-old boy who presented with a history of headache and vomiting and was found to have disseminated cysticercosis with pulmonary and cardiac involvement; the emphasis is on the rare occurrence of pulmonary, cardiac, pancreatic, intraocular, and extradural spinal canal involvement in the same patient. This case demonstrates the extent to which cysticercosis can be dis...
9. Electrocardiographically Determination of Cardiac Enlargements in Dogs
OpenAIRE
Gönül, Remzi; OR, Mehmet Erman; DODURKA, Tamer
2002-01-01
In this study, the electrocardiographic parameters necessary to determine cardiac enlargements and to establish and distinguish such complaints from each other in the early stage in dogs with circulatory problems were assessed. The material of the study consisted of 33 dogs 1.5-15 years of age with cardiac enlargements determined from 140 dogs suspected of having cardiac disease based on clinical, radiographic and electrocardiographic analyses. In these dogs, 12 cases of left atrial hypert...
10. Primary Prevention of Sudden Cardiac Death in Adults with Transposition of the Great Arteries: A Review of Implantable Cardioverter-Defibrillator Placement.
Science.gov (United States)
Sodhi, Sandeep S; Cedars, Ari M
2015-08-01
Transposition of the great arteries encompasses a set of structural congenital cardiac lesions that has in common ventriculoarterial discordance. Primarily because of advances in medical and surgical care, an increasing number of children born with this anomaly are surviving into adulthood. Depending upon the subtype of lesion or the particular corrective surgery that the patient might have undergone, this group of adult congenital heart disease patients constitutes a relatively new population with unique medical sequelae. Among the more common and difficult to manage are cardiac arrhythmias and other sequelae that can lead to sudden cardiac death. To date, the question of whether implantable cardioverter-defibrillators should be placed in this cohort as a preventive measure to abort sudden death has largely gone unanswered. Therefore, we review the available literature surrounding this issue. PMID:26413012
11. Cardiac Relapse of Acute Myeloid Leukemia after Allogeneic Hematopoietic Stem Cell Transplantation
Science.gov (United States)
Sánchez-Quintana, Ana; Quijada-Fumero, Alejandro; Laynez-Carnicero, Ana; Breña-Atienza, Joaquín; Poncela-Mireles, Francisco J.; Llanos-Gómez, Juan M.; Cabello-Rodríguez, Ana I.; Ramos-López, María
2016-01-01
Secondary or metastatic cardiac tumors are much more common than primary benign or malignant cardiac tumors. Any tumor can cause myocardial or pericardial metastasis, although isolated or combined tumor invasion of the pericardium is more common. Types of neoplasia with the highest rates of cardiac or pericardial involvement are melanoma, lung cancer, and breast and mediastinal carcinomas. Acute myeloid leukemia (AML) is the most common type of acute leukemia in adults. Initial treatment involves chemotherapy followed by consolidation treatment to reduce the risk of relapse. In high-risk patients, the treatment of choice for consolidation is hematopoietic stem cell transplantation (HSCT). Relapse of AML is the most common cause of HSCT failure. Extramedullary relapse is rare. The organs most frequently affected, called “sanctuaries,” are the testes, ovaries, and central nervous system. We present a case with extramedullary relapse in the form of a solid cardiac mass. PMID:27642531
12. Reentrant Supraventricular Tachycardia in a Pediatric Trauma Patient Masquerading as a Cardiac Contusion
Directory of Open Access Journals (Sweden)
2005-01-01
Full Text Available Establishing the etiology of tachycardia in a trauma patient is often difficult. Pediatric trauma patients present an even tougher challenge. Cardiac contusion should be suspected when other more common traumatic injuries that produce hypoxia and blood loss are excluded. The diagnosis of cardiac contusion is notoriously difficult to make largely due to the controversy over the definition of the disease, and the lack of a true gold standard confirmatory test. Atrioventricular nodal reentrant tachycardia (AVNRT is a common form of supraventricular tachycardia (SVT that can also present a diagnostic challenge to emergency physicians. While electrophysiologic studies are the gold standard for confirming the diagnosis, there are certain aspects of the history, electrocardiogram (ECG, and responses to cardiac maneuvers that strongly suggest the diagnosis. We present the case of a pediatric trauma patient that presented with new onset AVNRT masquerading as cardiac contusion.
13. Reentry Near the Percolation Threshold in a Heterogeneous Discrete Model for Cardiac Tissue
Science.gov (United States)
Alonso, Sergio; Bär, Markus
2013-04-01
Arrhythmias in cardiac tissue are related to irregular electrical wave propagation in the heart. Cardiac tissue is formed by a discrete cell network, which is often heterogeneous. A localized region with a fraction of nonconducting links surrounded by homogeneous conducting tissue can become a source of reentry and ectopic beats. Extensive simulations in a discrete model of cardiac tissue show that a wave crossing a heterogeneous region of cardiac tissue can disintegrate into irregular patterns, provided the fraction of nonconducting links is close to the percolation threshold of the cell network. The dependence of the reentry probability on this fraction, the system size, and the degree of excitability can be inferred from the size distribution of nonconducting clusters near the percolation threshold.
14. Polyunsaturated fatty acid analogs act antiarrhythmically on the cardiac IKs channel
DEFF Research Database (Denmark)
Liin, Sara I.; Silverå Ejneby, Malin; Barro-Soria, Rene;
2015-01-01
Polyunsaturated fatty acids (PUFAs) affect cardiac excitability. Kv7.1 and the β-subunit KCNE1 form the cardiac IKs channel that is central for cardiac repolarization. In this study, we explore the prospects of PUFAs as IKs channel modulators. We report that PUFAs open Kv7.1 via an electrostatic...... charge at neutral pH, restore the sensitivity to open IKs channels. PUFA analogs with a positively charged head group inhibit IKs channels. These different PUFA analogs could be developed into drugs to treat cardiac arrhythmias. In support of this possibility, we show that PUFA analogs act...... mechanism. Both the polyunsaturated acyl tail and the negatively charged carboxyl head group are required for PUFAs to open Kv7.1. We further show that KCNE1 coexpression abolishes the PUFA effect on Kv7.1 by promoting PUFA protonation. PUFA analogs with a decreased pKa value, to preserve their negative...
15. Evaluation of apical subtype of hypertrophic cardiomyopathy using cardiac magnetic resonance imaging with gadolinium enhancement.
Science.gov (United States)
Kebed, Kalie Y; Al Adham, Raed I; Bishu, Kalkidan; Askew, J Wells; Klarich, Kyle W; Araoz, Philip A; Foley, Thomas A; Glockner, James F; Nishimura, Rick A; Anavekar, Nandan S
2014-09-01
Apical hypertrophic cardiomyopathy (HC) is an uncommon variant of HC. We sought to characterize cardiac magnetic resonance imaging (MRI) findings among apical HC patients. This was a retrospective review of consecutive patients with a diagnosis of apical HC who underwent cardiac MRI examinations at the Mayo Clinic (Rochester, MN) from August 1999 to October 2011. Clinical and demographic data at the time of cardiac MRI study were abstracted. Cardiac MRI study and 2-dimensional echocardiograms performed within 6 months of the cardiac MRI were reviewed; 96 patients with apical HC underwent cardiac MRI examinations. LV end-diastolic and end-systolic volumes were 130.7 ± 39.1 ml and 44.2 ± 20.9 ml, respectively. Maximum LV thickness was 19 ± 5 mm. Hypertrophy extended beyond the apex into other segments in 57 (59.4%) patients. Obstructive physiology was seen in 12 (12.5%) and was more common in the mixed apical phenotype than the pure apical (19.3 vs 2.6%, p = 0.02). Apical pouches were noted in 39 (40.6%) patients. Late gadolinium enhancement (LGE) was present in 70 (74.5%) patients. LGE was associated with severe symptoms and increased maximal LV wall thickness. In conclusion, cardiac MRI is well suited for studying the apical form of HC because of difficulty imaging the cardiac apex with standard echocardiography. Cardiac MRI is uniquely suited to delineate the presence or absence of an apical pouch and abnormal myocardial LGE that may have implications in the natural history of apical HM. In particular, the presence of abnormal LGE is associated with clinical symptoms and increased wall thickness. PMID:25037678
16. The neural basis of body form and body action agnosia.
Science.gov (United States)
Moro, Valentina; Urgesi, Cosimo; Pernigo, Simone; Lanteri, Paola; Pazzaglia, Mariella; Aglioti, Salvatore Maria
2008-10-23
Visual analysis of faces and nonfacial body stimuli brings about neural activity in different cortical areas. Moreover, processing body form and body action relies on distinct neural substrates. Although brain lesion studies show specific face processing deficits, neuropsychological evidence for defective recognition of nonfacial body parts is lacking. By combining psychophysics studies with lesion-mapping techniques, we found that lesions of ventromedial, occipitotemporal areas induce face and body recognition deficits while lesions involving extrastriate body area seem causatively associated with impaired recognition of body but not of face and object stimuli. We also found that body form and body action recognition deficits can be double dissociated and are causatively associated with lesions to extrastriate body area and ventral premotor cortex, respectively. Our study reports two category-specific visual deficits, called body form and body action agnosia, and highlights their neural underpinnings.
17. Contact with Fluoride-Releasing Restorative Materials Can Arrest Simulated Approximal Caries Lesion
Directory of Open Access Journals (Sweden)
Camila de Almeida Brandão Guglielmi
2015-01-01
Full Text Available Previous studies have suggested that the presence of white-spot lesion is very probable when adjacent surface is affected by cavitated lesions. This study evaluated the potential of different fluoride-releasing restorative materials in arresting enamel white-spot lesions in approximal surface in contact with them, in vitro (I and in situ (II. White-spot lesions were formed in 240 primary enamel specimens via pH-cycling. They were put in contact with cylindrical blocks of 6 materials (n=20: composite resin, 2 high-viscous glass ionomer cements (HVGIC, resin-modified GIC, resin-modified nanoionomer, and polyacid-modified resin. In both studies I and II, these settings were designed to simulate the contact point between the restoration and simulated approximal lesion. For study I, they were subjected to a new pH-cycling cariogenic challenge for 7 or 14 days (n=10. For study II, a randomized double-blind in situ design was conducted in two phases (7/14 days to promote cariogenic challenge. At the end of both studies, specimens were collected for mineral analysis by cross-sectional microhardness. Higher mineral loss was observed for lesions in contact with resin (p<0.001. HVGICs were the most efficient in preventing mineral loss, whereas other materials presented an intermediate behavior. It is concluded that fluoride-releasing materials can moderately reduce white-spot lesions progression, and HVGIC can arrest enamel lesion in approximal surface in contact with them.
18. [Out-of-hospital cardiac arrest].
Science.gov (United States)
Virkkunen, Ilkka; Hoppu, Sanna; Kämäräinen, Antti
2011-01-01
Cardiac arrest as the first symptom of coronary artery disease is not uncommon. Some of previously healthy people with sudden cardiac arrest may be saved by effective resuscitation and post-resuscitative therapy. The majority of cardiac arrest patients experience the cardiac arrest outside of the hospital, in which case early recognition of lifelessness, commencement of basic life support and entry to professional care without delay are the prerequisites for recovery. After the heart has started beating again, the clinical picture of post-resuscitation syndrome must be recognized and appropriate treatment utilized. PMID:22204143
19. Detecting deterministic dy namics of cardiac rhythm
Institute of Scientific and Technical Information of China (English)
2001-01-01
Under the acceptable hypothesis that cardiac rhythm is an approximately deterministic process with a small scale noise component, an available way is provided to construct a model that can reflect its prominent dynamics of the deterministic component. When applied to the analysis of 19 heart rate data sets, three main findings are stated. The obtained model can reflect prominent dynamics of the deterministic component of cardiac rhythm; cardiac chaos is stated in a reliable way; dynamical noise plays an important role in the generation of complex cardiac rhythm.
20. Cosmic Forms
CERN Document Server
Kleman, Maurice
2011-01-01
The continuous 1D defects of an isotropic homogeneous material in an Euclidean 3D space are classified by a construction method, the Volterra process (VP). We employ the same method to classify the continuous 2D defects (which we call \\textit{cosmic forms}) of a vacuum in a 4D maximally symmetric spacetime. These defects fall into three different classes: i)- $m$-forms, akin to 3D space disclinations, related to ordinary rotations and analogous to Kibble's global cosmic strings (except that being continuous any deficit angle is allowed); ii)- $t$-forms, related to Lorentz boosts (hyperbolic rotations); iii)- $r$-forms, never been considered so far, related to null rotations. A detailed account of their metrics is presented. Their inner structure in many cases appears as a non-singular \\textit{core} separated from the outer part by a timelike hypersurface with distributional curvature and/or torsion, yielding new types of geometrical interactions with cosmic dislocations and other cosmic disclinations. Whereas...
1. 42 CFR 410.49 - Cardiac rehabilitation program and intensive cardiac rehabilitation program: Conditions of coverage.
Science.gov (United States)
2010-10-01
... and intensive cardiac rehabilitation program: Conditions of coverage. (a) Definitions. As used in this... 42 Public Health 2 2010-10-01 2010-10-01 false Cardiac rehabilitation program and intensive cardiac rehabilitation program: Conditions of coverage. 410.49 Section 410.49 Public Health CENTERS...
2. Tumors of the cardiac conduction system: are they an explanation for otherwise unexplained sudden cardiac death?
Institute of Scientific and Technical Information of China (English)
2007-01-01
@@ Cardiac tumors are well described in the literature. The first reports of cardiac tumors date back hundreds of years.The prevalence of primary cardiac tumors at autopsy ranges from 0.001% to 0.3% with secondary tumors more common than in primary tumors.
3. The mechanism of lesion formation by focused ultrasound ablation catheter for treatment of atrial fibrillation
Science.gov (United States)
Sinelnikov, Y. D.; Fjield, T.; Sapozhnikov, O. A.
2009-10-01
The application of therapeutic ultrasound for the treatment of atrial fibrillation (AF) is investigated. The results of theoretical and experimental investigation of ultrasound ablation catheter are presented. The major components of the catheter are the high power cylindrical piezoelectric element and parabolic balloon reflector. Thermal elevation in the ostia of pulmonary veins is achieved by focusing the ultrasound beam in shape of a torus that transverses the myocardial tissue. High intensity ultrasound heating in the focal zone results in a lesion surrounding the pulmonary veins that creates an electrical conduction blocks and relief from AF symptoms. The success of the ablation procedure largely depends on the correct choice of reflector geometry and ultrasonic power. We present a theoretical model of the catheter’s acoustic field and bioheat transfer modeling of cardiac lesions. The application of an empirically derived relation between lesion formation and acoustic power is shown to correlate with the experimental data. Developed control methods combine the knowledge of theoretical acoustics and the thermal lesion formation simulations with experiment and thereby establish dosimetry that contributes to a safe and effective ultrasound ablation procedure.
4. Polymer fraction of Aloe vera exhibits a protective activity on ethanol-induced gastric lesions.
Science.gov (United States)
Park, Chul-Hong; Nam, Dong-Yoon; Son, Hyeong-U; Lee, Si-Rim; Lee, Hyun-Jin; Heo, Jin-Chul; Cha, Tae-Yang; Baek, Jin-Hong; Lee, Sang-Han
2011-04-01
For centuries, Aloe has been used as a herbal plant remedy against skin disorders, diabetes, and for its cardiac stimulatory activity. Here, we examined the gastroprotective effects of an Aloe vera polymer fraction (Avpf; molecular weight cut-off ≥50 kDa; 150 mg/kg body weight, p.o.) on an ethanol-induced gastric lesion mouse model. Mice pre-treated with Avpf had significantly fewer gastric lesions than their respective controls. To further examine the potential mechanism underlying this effect, we used reverse transcription-polymerase chain reaction to examine nitric oxide synthase and matrix metalloproteinase (MMP)mRNA expression on tissues from gastric lesions. Our results revealed that the mRNA expressions of inducible nitric oxide synthase (iNOS) and neuronal nitric oxide synthase (nNOS) were each reduced by ~50% in Avpf-treated mice vs. the controls, whereas, the mRNA expression levels of endothelial nitric oxide synthase remained unchanged. MMP-9, an index for gastric lesions, also alleviated the ethanol-treated gastric ulceration during Avpf treatment. These findings collectively suggest that Avpf significantly protects the gastric mucosa against ethanol-induced gastric damage, at least in part, by decreasing mRNA expression levels of not only iNOS and nNOS, but also MMP-9. PMID:21286662
5. Treatment of lesions of the rotator cuff.
Science.gov (United States)
Saggini, R; Cavezza, T; Di Pancrazio, L; Pisciella, V; Saladino, G; Zuccaro, M C; Bellomo, R G
2010-01-01
The impingement syndrome and tendinopathy of the rotator cuff are the most common causes (complaints) of pain and disability of the shoulder. The aim of this study is to evaluate the efficacy of a specific rehabilitative protocol, integrated with the administration of a nutritional supplement, in the conservative rehabilitative treatment, as well as in post-surgery, of patients with lesions of the rotator cuff. Two groups with syndrome of the rotator cuff were formed to follow different therapeutic courses, in relation to the choice of each subject to undergo the conservative treatment (Arm A) or the surgical one (Arm B). In Arm A the study included the association of therapy with ESWT (shock waves) with the proprioceptive Multi Joint System, for rehabilitating joint movement and muscle strength of the shoulder, and a specific nutritional supplement to reduce the pain and conserve the cartilage tissue. Between February 2009 and June 2009, we enrolled 30 subjects (randomized into three homogenous groups A1, A2, A3), average age 45±10 years, with rotator cuff syndrome with calcification of the shoulder, diagnosed through clinical examination and investigative instruments (X-ray, echography or NMR). In Arm B, from September 2009 to January 2010, we enrolled 50 patients (randomized into two groups, B1 and B2), 24 male (average age 58.4: min 28 and max 78) and 26 females (average age 59.5: min 30 and max 80), who had undergone rotator cuff operations and acromionplasty for non-massive lesions without important gleno-humeral instability, with either open or arthroscopic procedures. The analysis of the results of Arm A highlights that in terms of reducing pain the main benefits were found in Group A1 where the supplement was given. From the analysis of the data of Arm B, in both groups an improvement of the first 4 items evaluated was evident. In Group B1, 84 percent of the patients declared to be satisfied and improved and 16 percent were dissatisfied; in Group B2
6. Impact of cardiac rehabilitation on health related quality of life.
LENUS (Irish Health Repository)
Riaz, A
2012-02-01
Cardiac rehabilitation (CR) programs are recognized as integral part of the comprehensive care of patients with cardiovascular disease and are recommended as useful and effective (Class I) by the American Heart Association (AHA). In this study we used serial administration of the short form 36 (SF36) to evaluate patient\\'s response to CR in terms of improvement in Health related Quality of Life. A total of 49 patients were included in the analysis. There was a significant improvement observed after CR in the Physical Capacity Score (42.3 vs 49.9 p = 0.0005). There was no significant improvement in the Mental Capacity Score (54.8 vs 54.9 p = 0.96). We conclude that Cardiac Rehabilitation Program causes a significant improvement in the health related quality of life of patients by improving their physical health and well being but does not improve the mental capacity which is already at a healthy level before CR.
7. Optical control of excitation waves in cardiac tissue
Science.gov (United States)
Burton, Rebecca A. B.; Klimas, Aleksandra; Ambrosi, Christina M.; Tomek, Jakub; Corbett, Alex; Entcheva, Emilia; Bub, Gil
2015-12-01
In nature, macroscopic excitation waves are found in a diverse range of settings including chemical reactions, metal rust, yeast, amoeba and the heart and brain. In the case of living biological tissue, the spatiotemporal patterns formed by these excitation waves are different in healthy and diseased states. Current electrical and pharmacological methods for wave modulation lack the spatiotemporal precision needed to control these patterns. Optical methods have the potential to overcome these limitations, but to date have only been demonstrated in simple systems, such as the Belousov-Zhabotinsky chemical reaction. Here, we combine dye-free optical imaging with optogenetic actuation to achieve dynamic control of cardiac excitation waves. Illumination with patterned light is demonstrated to optically control the direction, speed and spiral chirality of such waves in cardiac tissue. This all-optical approach offers a new experimental platform for the study and control of pattern formation in complex biological excitable systems.
8. Autopsy study of small cardiac scars in Japanese men who lived in Hiroshima, Japan and Honolulu, Hawaii
International Nuclear Information System (INIS)
Japanese men long resident in Honolulu, Hawaii have significantly more ischemic heart disease, but significantly fewer small cardiac scars than men in Hiroshima, Japan. These scars occur in three forms: 1) small scars in the mural myocardium which account for the difference in frequency of small lesions in the two cities, and are of uncertain etiology; 2) areas of diffuse fibrosis in the papillary muscles. These are equally frequent in the two cities, and are associated with advancing age and sclerosis of papillary muscle arteries; and 3) focal scars in the papillary muscles. These are more frequent in Honolulu than Hiroshima. They are healed infarcts due to ischemic heart disease and are associated with a severe degree of extramural coronary artery sclerosis. Small mural myocardial scars, when present, are usually found in multiple sites, and are not related to age at death or heart weight. They are more common in the presence of sclerosis of intramural small arteries, but this association does not explain their more frequent occurrence in Hiroshima. There is no evidence that they are related to A-bomb radiation exposure. (author)
9. White Lesions Of The Oral Ca vity -diagnostic appraisal & management strategies
Directory of Open Access Journals (Sweden)
Hari S
2010-07-01
Full Text Available White lesions of the oral cavity constitute a rather common group of lesions that areencountered during routine clinical dental practice. The process of clinical diagnosis and treatmentplanning is of great concern to the patient as it determines the nature of future follow up care.There is a strong felt need for a rational and functional classification which will enable betterunderstanding of the basic disease process as well as in formulating a differential diagnosis. Clinicaldiagnostic skills and good judgment forms the key to successful management of white lesions of theoral cavity.
10. Osteolytic bone lesions – A rare presentation of AML M6.
Directory of Open Access Journals (Sweden)
Geetha N.
2015-02-01
Full Text Available Acute myeloid leukemia (AML M6 is a rare form of AML accounting for < 5 % of all AML. Extramedullary involvement is very rarely seen in this entity. Skeletal lesion has not been described in AML M6 before. We discuss the case of a 17 year old boy with AML M6 who presented with osteolytic lesion of right humerus. He was treated with induction and consolidation chemotherapy. The present case is the first report in literature of AML M6 presenting with skeletal lesions.
11. Crush stenting in treating coronary bifurcate lesions: paclitaxel eluting stents versus sirolimus eluting stents
Institute of Scientific and Technical Information of China (English)
CHEN Shao-liang; SUN Xue-wen; HU Da-yi; Tak W. Kwan; ZHANG Jun-jie; YE Fei; CHEN Yun-dai; ZHU Zhong-sheng; LIN Song; TIAN Nai-liang; LIU Zhi-zhong; FANG Wei-yi
2008-01-01
Background Because no data regarding the comparison of crush stenting with pactitaxel(PES)or sirolimus eluting stents(SES)for coronary bifurcate lesions have been reported,we compared the clinical outcomes of these two types of stents.Methods Two hundred and thirty patients with 242 bifurcate lesions were enrolled in a prospective,nonrandomized trial.Primary endpoints included myocardial infarction,cardiac death and target vessel revascularization at 8 months.Results All patients were followed up clinically and 82%angiographically at 8 months.Final kissing balloon inflation was performed in 72%in the PES and 75%in the SES groups(P＞0.05).Compared to the SES group,PES group had a higher late loss and incidence of restenosis(P=0.04)in the prebifurcation vessel segment.The postbifurcation vessel segment in the PES group had a greater late loss((0.7+0.6)mm vs(0.3±0.4)mm,P＜0.001)and higher restenosis in the side branch(25.5%vs 15.6%,P=0.04)when compared to the SES group.There was significant difference of insegment restenosis in the entire main vessel between PES and SES groups (P=0.004).Target lesion revascularization was more frequently seen in the PES group as compared to the SES group(P=0.01).There was significant difference in the accumulative MACE between these two groups(P=0.01).The survival rate free from target lesion revascularization was significantly higher in the SES group when compared to the PES group(P＜0.001).Conclusion SES is superior to PES in reducing restenosis and target lesion revascularization by 8-month follow-up after crush stenting for bifurcate lesions.
12. COMPLEJIDAD DE LAS LESIONES CORONARIAS EN PACIENTES DIABÉTICOS / Complexity of coronary lesions in diabetic patients
Directory of Open Access Journals (Sweden)
Héctor Conde Cerdeira
2012-03-01
Full Text Available Resumen Introducción y objetivos: La enfermedad coronaria en los pacientes diabéticos se presenta de forma muy agresiva con una excesiva progresión de la aterosclerosis y con mayor riesgo de reestenosis o trombosis de stent, en el intervencionismo coronario percutáneo. El objetivo de esta investigación fue determinar la relación entre la diabetes mellitus y determinadas características de las lesiones coronarias, así como su relación con la reestenosis, la trombosis y el desarrollo de nuevas lesiones después del procedimiento percutáneo. Método: Se realizó un estudio descriptivo-retrospectivo. De los 1.464 pacientes revascularizados en el Centro de Investigaciones Médico-Quirúrgicas de La Habana, Cuba, entre agosto de 1997 y febrero de 2009, se seleccionaron 270 pacientes diabéticos. Resultados: La diabetes mellitus fue un factor de riesgo para las lesiones de circunfleja (OR* = 1,48; de los ostium aorto-coronario (OR = 3,58, de descendente anterior (OR = 2,41 y de circunfleja (OR = 4,89; y para las lesiones de tronco con extensión a descendente anterior (OR = 9,79. Los diabéticos tuvieron más riesgo de desarrollar lesiones complejas tipo B2 y C (OR = 1,36, en curvaturas mayores de 90º (OR = 3,03, con curvaturas previas superiores de 90º (OR = 6,13, lesiones de más de 20 mm (OR = 2,0, en ramificaciones (OR = 1,69 y lesiones por ausencia de flujo coronario (OR = 4,15. Se caracterizaron también por tener arterias menores de 3 mm (OR =1,32 y mayor riesgo de desarrollar nuevas lesiones (OR = 2,11, reestenosis (OR = 2,11 y trombosis (OR = 3,06 del stent. Conclusiones: La diabetes mellitus se comportó como un factor de riesgo para el desarrollo de lesiones coronarias complejas y con un elevado riesgo de desarrollar nuevas lesiones, reestenosis y trombosis de los stents. / Abstract Introduction and Objectives: Coronary artery disease in diabetic patients is presented in a very aggressive form with excessive progression of
13. EVALUATION OF NEONATAL CARDIAC MURMURS
Directory of Open Access Journals (Sweden)
Somaiah
2014-09-01
Full Text Available Cardiovascular malformations are the most common cause of congenital malformations, the diagnosis of which requires a close observation in the neonatal period. Early recognition of CHD is important in the neonatal period, as many of them may be fatal if undiagnosed and may require immediate intervention. The objectives of this study are to study the epidemiology of neonatal cardiac murmurs, to identify clinical characteristics which differentiate pathological murmur from functional murmurs and to assess the reliability of clinical evaluation in diagnosing CHD. Method of study included all neonates admitted to the NICU, postnatal ward, attending pediatric OPD or neonatal follow up clinic and were detected to have cardiac murmurs. It was a cross sectional study over a period of 16months. A clinical diagnosis was made based on history and clinical examination. Then Chest X-ray and ECG, Echocardiography was done in all neonates for confirmation of the diagnosis. These neonates were again examined daily till they were in hospital and during the follow-up visit at 6 weeks. The results of 70 neonates in this study conducted over a period of 24 months included the incidence of cardiac murmurs among intramural neonates which was 13.5 for 1000 live births. Most frequent symptom was fast breathing in 10(14.3% cases. VSD was the most common diagnosis clinically in 23 (33% babies. The most frequent Echo diagnosis was acyanotic complex congenital heart disease in 25(36% cases followed by 12(17% cases each of VSD and ASD respectively. Overall in our study 77.1% (54cases of the murmurs were diagnosed correctly and confirmed by Echocardiography The study concluded that it is possible to make clinical diagnosis in many cases of congenital heart diseases, the functional murmurs could be differentiated from those arising from structural heart disease and evaluation of the infants based only on murmurs, few congenital heart diseases can be missed.
14. Cerebral oximetry in cardiac anesthesia
Science.gov (United States)
Vretzakis, George; Georgopoulou, Stauroula; Stamoulis, Konstantinos; Stamatiou, Georgia; Tsakiridis, Kosmas; Katsikogianis, Nikolaos; Kougioumtzi, Ioanna; Machairiotis, Nikolaos; Tsiouda, Theodora; Mpakas, Andreas; Beleveslis, Thomas; Koletas, Alexander; Siminelakis, Stavros N.; Zarogoulidis, Konstantinos
2014-01-01
Cerebral oximetry based on near-infrared spectroscopy (NIRS) is increasingly used during the perioperative period of cardiovascular operations. It is a noninvasive technology that can monitor the regional oxygen saturation of the frontal cortex. Current literature indicates that it can stratify patients preoperatively according their risk. Intraoperatively, it provides continuous information about brain oxygenation and allows the use of brain as sentinel organ indexing overall organ perfusion and injury. This review focuses on the clinical validity and applicability of this monitor for cardiac surgical patients. PMID:24672700
15. Cardiac leiomyosarcoma, a case report
DEFF Research Database (Denmark)
Andersen, Rikke; Kristensen, Bjarne W; Gill, Sabine
2013-01-01
In this case report we present the history of a patient admitted with recurrent pulmonary edema. Transesophageal chocardiography showed a tumour in the left atrium, occluding the ostium of the mitral valve and mimicking intermittent mitral stenosis. Cardiac surgery followed by pathological...... examination revealed that the tumour was a leiomyosarcoma. Images from the echocardiography as well as the pathological findings are shown and discussed. The present case report illustrates that atrial tumors comprise also sarcomas, suggesting the use of careful, rapid diagnostic procedures and treatment...
16. Cardiac imaging: does radiation matter?
Science.gov (United States)
Einstein, Andrew J.; Knuuti, Juhani
2012-01-01
The use of ionizing radiation in cardiovascular imaging has generated considerable discussion. Radiation should not be considered in isolation, but rather in the context of a careful examination of the benefits, risks, and costs of cardiovascular imaging. Such consideration requires an understanding of some fundamental aspects of the biology, physics, epidemiology, and terminology germane to radiation, as well as principles of radiological protection. This paper offers a concise, contemporary perspective on these areas by addressing pertinent questions relating to radiation and its application to cardiac imaging. PMID:21828062
17. Autologous Transfusion in Cardiac Surgery
Directory of Open Access Journals (Sweden)
2003-11-01
Full Text Available Preoperative autologous blood donation is commonly used to reduce exposure to homologous blood transfusions among patients undergoing elective cardiac surgery. The aim of this study was to evaluate the effect of autologous transfusion on patients' hematocryte value, intra and postoperative blood loss, hospitalization time, the development of infective complications and other factors. Materials and Methods: Between June 2001 to April 2002, 208 patients were underwent cardiac surgery in cardiac surgery ward in Imam Khomeini Medical Center. One or more blood units donate from 104 Patients before cardiopulmonary bypass and heparin injection, and transfused to them after CPB and Protamin injection (autologous Group, group 1. 104 patients underwent cardiac surgery routinely (control group, group 2."nResults: Mean of age was 55.9±8.6 in group 1 and 56.6±9.3 in group 2 (P=NS. 73 male and 31 females were in group 1 and 79 males and 25 females were in group 2 (P=NS. Smoking, familial history, hyperlipidemia, diabetes mellitus, renal failure, hypertension, stroke, and history of myocardial infarction was similar in two groups."nSeverity of angina, urgency operation, number vessels disease, duration of cardiopulmonary bypass, duration of aortic cross clamp time, use of internal thoracic artery graft, and number of grafts was similar in both groups. Mean of bleeding post operation was 548 cc in group 1 and 803 cc in-group 2 (P=0.003. Bleeding that need to operation was 1.8% in group 1 and 8.6% in group 2 (P=0.002. Wound infection, mediastinitis, renal failure, ventilatory prolonged, stroke, need to Intra-aortic Balloon Pump (IABP, intraoperative bleeding, and hospital stay was similar in both groups. Mean of extubationt time was 10.2 hours in group 1 and 14.8 hours in group 2 (P=0.001."nConclusion: Preoperative and intra-operative donations are safe and continue to contribute uniquely to blood conservation, providing important options in comprehensive
18. [Acute cardiac failure in pheochromocytoma.
DEFF Research Database (Denmark)
Jønler, Morten; Munk, Kim
2008-01-01
Pheochromocytoma (P) is an endocrine catecholamine-secreting tumor. Classical symptoms like hypertension, attacks of sweating, palpitations, headache and palor are related to catecholamine discharge. We provide a case of P in a 71 year-old man presenting with acute cardiac failure, severe reduction...... in left ventricular function and elevated myocardial enzymes. No coronary stenoses were found. The myocardium regained nearly normal systolic function in one and a half month. A renal P was laparoscopicaly removed. We discuss the pathophysiology of catecholamine cardiomyopathy. Udgivelsesdato: 2008-Jun-2...
19. Introduction to noninvasive cardiac mapping.
Science.gov (United States)
Bear, Laura; Cuculich, Phillip S; Bernus, Olivier; Efimov, Igor; Dubois, Rémi
2015-03-01
From the dawn of the twentieth century, the electrocardiogram (ECG) has revolutionized the way clinical cardiology has been practiced, and it has become the cornerstone of modern medicine today. Driven by clinical and research needs for a more precise understanding of cardiac electrophysiology beyond traditional ECG, inverse solution electrocardiography has been developed, tested, and validated. This article outlines the important progress from ECG development, through more extensive measurement of body surface potentials, and the fundamental leap to solving the inverse problem of electrocardiography, with a focus on mathematical methods and experimental validation. PMID:25784020
20. 10.2.Cardiac arrhythmias
Institute of Scientific and Technical Information of China (English)
1993-01-01
930257 Electrophysiologic study of reperfu-sion arrhythmias.YIN Hong (尹红),et al.Af-fil Hosp,Shandong Med Univ,Jinan.Chin CirJ 1993;8(1):37—39.Twenty dogs of experimental ischemic reper-fusion were studied with a three-dimensionalmapping system of cardiac electric activity andmultiple—level myocardial recordings by bipolarplunge—needle electrodes.27% of the nonsus-tained ventricular tachycardia (NSVT) of intra-mural reentry occurred in the ischemic subendo-
1. Clinical outcomes after treatment of multiple lesions with zotarolimus-eluting versus sirolimus-eluting coronary stents (a SORT OUT III substudy
Directory of Open Access Journals (Sweden)
Thim Troels
2012-03-01
Full Text Available Abstract Background Data on clinical outcomes among patients treated with the zotarolimus-eluting Endeavor™ stent versus the sirolimus-eluting Cypher™ stent favor the sirolimus-eluting stent. However, a separate comparison of clinical outcome among patients treated for multiple lesions with these stents is lacking. We performed this comparison within the SORT OUT III trial data set. Methods Among 2332 patients randomized in SORT OUT III, 695 were treated for multiple lesions with zotarolimus-eluting (n = 350 or sirolimus-eluting (n = 345 stents and followed for 18 months. Major adverse cardiac events (MACE; composite of cardiac death, myocardial infarction, or target vessel revascularization (TVR; was the primary endpoint. Results Zotarolimus-eluting compared to sirolimus-eluting stent treatment was associated with increased MACE rate (13.2% vs. 2.6%; hazard ratio 5.29 with 95% confidence interval: 2.59-10.8. All secondary endpoints; all cause death, cardiac death, myocardial infarction, TVR, target lesion revascularization, in-stent restenosis, and definite stent thrombosis; were observed more frequently among zotarolimus-eluting stent treated patients. For all endpoints, hazard ratios were 1.6 to 4.6 times higher than in the overall results of the SORT OUT III trial. Conclusions We observed better clinical outcomes among patients treated for multiple lesions with the sirolimus-eluting stent compared to those treated with the zotarolimus-eluting stent.
2. Diagnostic Concordance Characteristics of Oral Cavity Lesions
Directory of Open Access Journals (Sweden)
Ufuk Tatli
2013-01-01
Full Text Available Purpose. The objective of this study was to evaluate the diagnostic concordance characteristics of oral cavity lesions by comparing the clinical diagnosis of the lesions with the histopathologic diagnosis. Material and Method. A retrospective analysis was conducted on the patients, who were admitted with oral cavity pathology and underwent biopsy procedure between 2007 and 2011. The oral cavity lesions were classified into 6 different groups as odontogenic cysts, nonodontogenic cysts, odontogenic tumors, nonodontogenic tumors, malignant tumors, and precancerous lesions in accordance with the 2005 WHO classification. The diagnoses were also recategorized into 3 groups expressing prognostic implications as benign, precancerous, and malignant. The initial clinical diagnoses were compared with the histopathologic diagnoses. Data were analyzed statistically. Results. A total of 2718 cases were included. Histopathologic diagnosis did not match the clinical diagnosis in 6.7% of the cases. Nonodontogenic tumors and malignant tumors had the highest misdiagnosis rates (11.5% and 9%, resp., followed by odontogenic tumors (7.7%, precancerous lesions (6.9%, and odontogenic cysts (4.4%. Clinicians were excelled in diagnosis of benign and precancerous lesions in clinical setting. Conclusion. The detailed discordance characteristics for each specific lesion should be considered during oral pathology practice to provide early detection without delay.
3. Usefulness of acoustic radiation force impulse elastography in the differential diagnosis of benign and malignant solid pancreatic lesions
Energy Technology Data Exchange (ETDEWEB)
Park, Min Kyoung; Jo, Jeong Hyun; Kwon, Hee Jin; Cho, Jin Han; Oh, Jong Young; Noh, Myung Hwan; Nam, Kyung Jin [Dong-A University College of Medicine, Busan (Korea, Republic of)
2014-03-15
The aim of this study was to evaluate the tissue stiffness of solid pancreatic lesions by using acoustic radiation force impulse (ARFI) elastography to differentiate benign from malignant pancreatic lesions. ARFI elastography was performed in 26 patients who had 27 focal solid pancreatic lesions, including 8 benign lesions (mass-forming pancreatitis, 5; autoimmune pancreatitis, 3) and 19 malignant lesions (pancreatic adenocarcinoma, 16; metastasis from colorectal cancer, 2; malignant neuroendocrine tumor, 1). On the elastographic images of virtual touch tissue imaging (VTI), the echogenicity of the mass was categorized on a 5-grade scale. On the elastographic image of virtual touch tissue quantification (VTQ), the shear wave velocities (SWVs) of the lesion and surrounding parenchyma were measured. On the VTI images, the mean echogenicity score of the malignant lesions (3.7±1.0) was higher than that of the benign lesions (3.1±0.4; P=0.023). On the VTQ images, there were no statistical differences in the mean SWV between the benign (2.4±1.1 m/sec) and malignant (3.3±1.0 m/sec) lesions (P=0.101). However, the mean SWV difference values between the lesion and background parenchyma of the malignant lesions (1.5±0.8 m/sec) were higher than those of the benign lesions (0.4±0.3 m/sec; P=0.011). ARFI elastography can determine the relative stiffness between a lesion and the background pancreatic parenchyma using VTI and VTQ, which is helpful in the differentiation between benign and malignant solid pancreatic lesions.
4. Assessment of cardiac sympathetic nerve integrity with positron emission tomography
Energy Technology Data Exchange (ETDEWEB)
Raffel, David M. E-mail: raffel@umich.edu; Wieland, Donald M
2001-07-01
The autonomic nervous system plays a critical role in the regulation of cardiac function. Abnormalities of cardiac innervation have been implicated in the pathophysiology of many heart diseases, including sudden cardiac death and congestive heart failure. In an effort to provide clinicians with the ability to regionally map cardiac innervation, several radiotracers for imaging cardiac sympathetic neurons have been developed. This paper reviews the development of neuronal imaging agents and discusses their emerging role in the noninvasive assessment of cardiac sympathetic innervation.
5. The Cardiac Conduction System: Generation and Conduction of the Cardiac Impulse.
Science.gov (United States)
Kennedy, Alan; Finlay, Dewar D; Guldenring, Daniel; Bond, Raymond; Moran, Kieran; McLaughlin, James
2016-09-01
In this article, the authors outline the key components behind the automated generation of the cardiac impulses and the effect these impulses have on cardiac myocytes. Also, a description of the key components of the normal cardiac conduction system is provided, including the sinoatrial node, the atrioventricular node, the His bundle, the bundle branches, and the Purkinje network. Finally, an outline of how each stage of the cardiac conduction system is represented on the electrocardiogram is described, allowing the reader of the electrocardiogram to translate background information about the normal cardiac conduction system to everyday clinical practice. PMID:27484656
6. Macromolecular lesions and cellular radiation chemistry
International Nuclear Information System (INIS)
Our studies of the interaction of densely ionizing particles with macromolecules in the living cell may be divided into four parts: characterization of lesions to cellular DNA in the unmodified Bragg ionization curve; characterization of lesions to cellular DNA in the spread Bragg curve as used in radiation therapy; elucidation of the cellular radiation chemistry characteristic of high vs. low LET radiation qualities; and the introduction of novel techniques designed to give a better understanding of the fundamental properties of induction of lesions and their repair potentials in high LET radiation
7. Tibial cortical lesions: A multimodality pictorial review
Energy Technology Data Exchange (ETDEWEB)
2015-01-15
Highlights: • Multimodality imaging plays an important role in the investigation and diagnosis of shin pain. • We review the multimodality imaging findings of common cortically based tibial lesions. • We also describe the rarer pathologies of tibial cortical lesions. - Abstract: Shin pain is a common complaint, particularly in young and active patients, with a wide range of potential diagnoses and resulting implications. We review the natural history and multimodality imaging findings of the more common causes of cortically-based tibial lesions, as well as the rarer pathologies less frequently encountered in a general radiology department.
8. Oncocytic lesions of the ophthalmic region
DEFF Research Database (Denmark)
Østergaard, Jens; Prause, Jan U; Heegaard, Steffen
2011-01-01
Purpose: This study aimed to make a nationwide clinicopathological study of oncocytic lesions in the ophthalmic region and to characterize their cytokeratin (CK) expression. Methods: All histologically diagnosed oncocytic lesions in the ophthalmic region registered in Denmark over a 25-year period...... expression. Basal-type oncocytic cells reacted with antibodies against CK 5/6, CK 7, CK 8, CK 13, CK 14, CK 17, CK 18 and CK 19, and suprabasal cells with CK 4, CK 7, CK 8, CK 18 and CK 19. Antibodies against CK 1+10 and CK 20 showed no reaction. Conclusions: Oncocytic lesions of the ophthalmic region most...
9. A cardiac hemangioma treated by a right minithoracotomy approach with thoracoscopic assistance.
Science.gov (United States)
Sakai, Katsuaki; Tanigawa, Kazuyoshi; Odate, Tomohiro; Miura, Takashi; Tsuneto, Akira; Abe, Kuniko; Hashizume, Koji; Eishi, Kiyoyuki
2016-01-01
Cardiac hemangiomas are extremely rare tumors, accounting for only 2.5% of all cardiac tumors. Most of these develop in the ventricles, and obtaining a good field of view is, therefore, the key to successful operation. A 40-year-old female visited a local hospital due to palpitation. Transthoracic echocardiography revealed a spherical high-echo mass (13.5 × 10.7 mm in diameter) between the papillary muscles. She was referred to our hospital to undergo close examination. Cardiac contrast-enhanced magnetic resonance imaging was performed to differentiate between malignant and benign lesions. However, this did not provide any findings leading to a definite diagnosis. To make a diagnosis and prevent embolism, the mass was excised using a right minithoracotomy approach with thoracoscopic assistance. The post-operative pathological diagnosis was a cardiac capillary-cavernous hemangioma. A right minithoracotomy approach combined with thoracoscopy allowed accurate evaluation of the mass in the left ventricle beyond the mitral valve and its accurate excision.
10. Cardiac cell proliferation assessed by EdU, a novel analysis of cardiac regeneration.
Science.gov (United States)
Zeng, Bin; Tong, Suiyang; Ren, Xiaofeng; Xia, Hao
2016-08-01
Emerging evidence suggests that mammalian hearts maintain the capacity for cardiac regeneration. Rapid and sensitive identification of cardiac cellular proliferation is prerequisite for understanding the underlying mechanisms and strategies of cardiac regeneration. The following immunologically related markers of cardiac cells were analyzed: cardiac transcription factors Nkx2.5 and Gata 4; specific marker of cardiomyocytes TnT; endothelial cell marker CD31; vascular smooth muscle marker smooth muscle myosin IgG; cardiac resident stem cells markers IsL1, Tbx18, and Wt1. Markers were co-localized in cardiac tissues of embryonic, neonatal, adult, and pathological samples by 5-ethynyl-2'-deoxyuridine (EdU) staining. EdU was also used to label isolated neonatal cardiomyocytes in vitro. EdU robustly labeled proliferating cells in vitro and in vivo, co-immunostaining with different cardiac cells markers. EdU can rapidly and sensitively label proliferating cardiac cells in developmental and pathological states. Cardiac cell proliferation assessed by EdU is a novel analytical tool for investigating the mechanism and strategies of cardiac regeneration in response to injury. PMID:25480318
11. Automorphic Forms
DEFF Research Database (Denmark)
von Essen, Flemming Brændgaard
-functions for Hecke characters in the points 4 and 6. It is well known, that all zeros of the Eisenstein series Ek wrt. SL2(Z) in the standard fundamental domain has modulus 1. We show that this is also true for #n Ek, where # is a certain differential operator. We then proceed to study logarithms of multiplier...... systems. For automorphic forms wrt. Hecke triangle groups and Fuchsian groups with no elliptic elements and genus 0, we show that some logarithms of multiplier systems can be interpreted as a linking number. Finally we show a "twisted" version of the prime geodesics theorem, and logarithms of multiplier...
12. Cardiac hydatid cyst revealed by ventricular tachycardia
OpenAIRE
2013-01-01
Hydatid disease is a human parasitic infestation caused by the larval stage of Echinococcus Granulosus. The liver and the lungs are the most common locations. Cardiac involvement is rare and accounts for 0.5–2% of all hydatid disease. We report an unusual presentation of cardiac hydatid cyst revealed by ventricular tachycardia in a patient with a history of cerebral hydatid cyst.
13. Acute cardiac failure in neuroleptic malignant syndrome.
LENUS (Irish Health Repository)
Sparrow, Patrick
2012-02-03
We present a case of rapid onset acute cardiac failure developing as part of neuroleptic malignant syndrome in a 35-year-old woman following treatment with thioridazine and lithium. Post mortem histology of cardiac and skeletal muscle showed similar changes of focal cellular necrosis and vacuolation suggesting a common disease process.
14. Cardiac MRI of the athlete's heart
NARCIS (Netherlands)
Prakken, N.H.J.
2010-01-01
The increase in pre-participation cardiovascular screening using the Lausanne protocol will ultimately lead to an increased use of cardiac MRI and MDCT in the cardiovascular work-up of athletes. The role of cardiac MRI is well established in the evaluation of cardiomyopathies, myocarditis, aortic st
15. The Western Denmark Cardiac Computed Tomography Registry
DEFF Research Database (Denmark)
Nielsen, Lene Hüche; Nørgaard, Bjarne Linde; Tilsted, Hans Henrik;
2015-01-01
BACKGROUND: As a subregistry to the Western Denmark Heart Registry (WDHR), the Western Denmark Cardiac Computed Tomography Registry (WDHR-CCTR) is a clinical database established in 2008 to monitor and improve the quality of cardiac computed tomography (CT) in Western Denmark. OBJECTIVE: We...
16. Fetal cardiac interventions: clinical and experimental research.
Science.gov (United States)
Yuan, Shi-Min; Humuruola, Gulimila
2016-01-01
Fetal cardiac interventions for congenital heart diseases may alleviate heart dysfunction, prevent them evolving into hypoplastic left heart syndrome, achieve biventricular outcome and improve fetal survival. Candidates for clinical fetal cardiac interventions are now restricted to cases of critical aortic valve stenosis with evolving hypoplastic left heart syndrome, pulmonary atresia with an intact ventricular septum and evolving hypoplastic right heart syndrome, and hypoplastic left heart syndrome with an intact or highly restrictive atrial septum as well as fetal heart block. The therapeutic options are advocated as prenatal aortic valvuloplasty, pulmonary valvuloplasty, creation of interatrial communication and fetal cardiac pacing. Experimental research on fetal cardiac intervention involves technical modifications of catheter-based cardiac clinical interventions and open fetal cardiac bypass that cannot be applied in human fetuses for the time being. Clinical fetal cardiac interventions are plausible for midgestation fetuses with the above-mentioned congenital heart defects. The technical success, biventricular outcome and fetal survival are continuously being improved in the conditions of the sophisticated multidisciplinary team, equipment, techniques and postnatal care. Experimental research is laying the foundations and may open new fields for catheter-based clinical techniques. In the present article, the clinical therapeutic options and experimental fetal cardiac interventions are described. PMID:27279868
17. Is fetal cardiac function gender dependent?
NARCIS (Netherlands)
Clur, S. A. B.; Rengerink, K. Oude; Mol, B. W.; Ottenkamp, J.; Bilardo, C. M.
2011-01-01
Introduction An increased nuchal translucency (NT) is more common in males. A delayed diastolic cardiac function maturation has been proposed to explain this and the reported gender-related differences in ductus venosus (DV) flow. Objective To investigate gender-related differences in fetal cardiac
18. Is fetal cardiac function gender dependent?
NARCIS (Netherlands)
S.A.B. Clur; K. Oude Rengerink; B.W. Mol; J. Ottenkamp; C.M. Bilardo
2011-01-01
An increased nuchal translucency (NT) is more common in males. A delayed diastolic cardiac function maturation has been proposed to explain this and the reported gender-related differences in ductus venosus (DV) flow. To investigate gender-related differences in fetal cardiac function. One hundred a
19. Preoperative respiratory physical therapy in cardiac surgery
NARCIS (Netherlands)
Hulzebos, H.J.
2006-01-01
Cardiac surgery is one of the most common surgical procedures and accounts for more resources expended in cardiovascular medicine than any other single procedure. Because cardiac surgery involves sternal incision and cardiopulmonary bypass, patients usually have a restricted respiratory function in
20. Cardiac Diseases in People with Intellectual Disability
Science.gov (United States)
van den Akker, M.; Maaskant, M. A.; van der Meijden, R. J. M.
2006-01-01
Background: In people with ID there is more morbidity than in the general population, including cardiac diseases. Dutch figures on this subject are scarce. Methods: Descriptive study of the prevalence of cardiac diseases in 436 residential clients in Echt, the Netherlands, and comparisons between men and women, age groups, and level and aetiology…
1. Coagulopathy and hemostatic monitoring in cardiac surgery
DEFF Research Database (Denmark)
Johansson, Pär I; Sølbeck, Sacha; Genet, Gustav;
2012-01-01
Cardiac surgery with cardiopulmonary bypass (CPB) causes severe derangements in the hemostatic system, which in turn puts the patient at risks of microvascular bleeding. Excessive transfusion and surgical re-exploration after cardiac surgery are potentially associated with a number of adverse...
2. Athletes at Risk for Sudden Cardiac Death
Science.gov (United States)
Subasic, Kim
2010-01-01
High school athletes represent the largest group of individuals affected by sudden cardiac death, with an estimated incidence of once or twice per week. Structural cardiovascular abnormalities are the most frequent cause of sudden cardiac death. Athletes participating in basketball, football, track, soccer, baseball, and swimming were found to…
3. CARDIAC SIZE IN THE SUPINE CHESTFILM
NARCIS (Netherlands)
VANDERJAGT, EJ; SMITS, HJ
1992-01-01
The aim of this study was to find a normal value for the cardiac size in the supine position because such a standard is hardly known in the literature. Cardiac size in the erect and supine positions were compared in 165 patients in whom both chest radiographs were performed prior to kidney transplan
4. Using the Trajectory Framework: reconceptualizing cardiac illness.
Science.gov (United States)
Hawthorne, M H
1991-01-01
Cardiac disease is known to be the leading cause of premature morbidity and mortality in the United States. Nursing management of cardiac illnesses, as such, is a primary concern for most practicing nurses. Dramatic changes in cardiac patient populations and associated technology available for treatment indicate a need to reconceptualize the nature of cardiac illness and to consider alternative approaches to guide the care of these patients. Traditional care, to a large degree, has focused upon acute illness, consequently limiting needed attention to the increasing group of patients suffering chronic illness and disability. In the present paper, the major changes in the cardiac patient population and in utilization of available technology are presented. The application of the Corbin and Strauss trajectory framework as an appropriate and useful framework for conceptualizing cardiac illness and care is then discussed. Five characteristics of the framework which render the model particularly well suited to address cardiac care are identified and discussed. These characteristics are: 1) comprehensiveness of care, 2) patient-centered care, 3) gender issues in care, 4) family-focused care, 5) technology and cardiac care. PMID:1763241
5. Cardiac arrhythmia classification using autoregressive modeling
OpenAIRE
Srinivasan Narayanan; Ge Dingfei; Krishnan Shankar M
2002-01-01
Abstract Background Computer-assisted arrhythmia recognition is critical for the management of cardiac disorders. Various techniques have been utilized to classify arrhythmias. Generally, these techniques classify two or three arrhythmias or have significantly large processing times. A simpler autoregressive modeling (AR) technique is proposed to classify normal sinus rhythm (NSR) and various cardiac arrhythmias including atrial premature contraction (APC), premature ventricular contraction (...
6. Conditional shape models for cardiac motion estimation
DEFF Research Database (Denmark)
Metz, C.T.; Baka, N.; Kirisli, H.A.;
2010-01-01
We propose a conditional statistical shape model to predict patient specific cardiac motion from the 3D end-diastolic CTA scan. The model is built from 4D CTA sequences by combining atlas based segmentation and 4D registration. Cardiac motion estimation is, for example, relevant in the dynamic al...
7. Drugs, QTc prolongation and sudden cardiac death
NARCIS (Netherlands)
S.M.J.M. Straus (Sabine)
2005-01-01
textabstract__Abstract__ The term sudden cardiac death pertains to an unexpected death from cardiac causes within a short time period and has been described throughout history. The ancient Egyptians inscribed on the tomb of a nobleman some 4500 years ago that he had died suddenly and without appare
8. Clinical study of cardiac diseases during pregnancy
Directory of Open Access Journals (Sweden)
Amitha Vijay Kamat
2016-03-01
Conclusions: Cardiac diseases in pregnancy constitute high risk pregnancy and require special attention during antepartum, intrapartum and postpartum period. Rheumatic heart disease was the major contribution of cardiac diseases in pregnancy and is seen to be associated with increased maternal morbidity. [Int J Reprod Contracept Obstet Gynecol 2016; 5(3.000: 855-859
9. Primary cardiac hemangioendothelioma: a case report
Institute of Scientific and Technical Information of China (English)
WANG Li-feng; LIU Ming; ZHU Hong; HAN Wei; HU Cheng-yi; QI Ji-ping; MEI Huan-lin; GE Re-le; ZHOU Min
2006-01-01
@@ Primary cardiac hemangioendothelioma is extremely rare.1-3 Up to now less than twenty cases have been reported in English literature, the data about this kind of cardiac tumors are scanty. In this report, a case of a huge hemangio-endothelioma that arose from the right atrium and was successfully resected is presented.
10. Cardiac manifestations of inborn errors of metabolism.
NARCIS (Netherlands)
Evangeliou, A.; Papadopoulou-Legbelou, K.; Daphnis, E.; Ganotakis, E.; Vavouranakis, I.; Michailidou, H.; Hitoglou-Makedou, A.; Nicolaidou, P.; Wevers, R.A.; Varlamis, G.
2007-01-01
AIM: The aim of the study was to investigate the frequency and type of cardiac manifestations in a defined group of patients with inborn errors of metabolism. This paper also explores the key role of cardiac manifestations in the diagnosis of inborn errors of metabolism in daily practice. METHODS: O
11. Ultrasound Imaging in Teaching Cardiac Physiology
Science.gov (United States)
Johnson, Christopher D.; Montgomery, Laura E. A.; Quinn, Joe G.; Roe, Sean M.; Stewart, Michael T.; Tansey, Etain A.
2016-01-01
This laboratory session provides hands-on experience for students to visualize the beating human heart with ultrasound imaging. Simple views are obtained from which students can directly measure important cardiac dimensions in systole and diastole. This allows students to derive, from first principles, important measures of cardiac function, such…
12. Stem cell sources for cardiac regeneration
NARCIS (Netherlands)
Roccio, M.; Goumans, M. J.; Sluijter, J. P. G.; Doevendans, P. A.
2008-01-01
Cell-based cardiac repair has the ambitious aim to replace the malfunctioning cardiac muscle developed after myocardial infarction, with new contractile cardiomyocytes and vessels. Different stem cell populations have been intensively studied in the last decade as a potential source of new cardiomyo
13. Cardiac Vagal Regulation and Early Peer Status
Science.gov (United States)
Graziano, Paulo A.; Keane, Susan P.; Calkins, Susan D.
2007-01-01
A sample of 341 5 1/2-year-old children participating in an ongoing longitudinal study was the focus of a study on the relation between cardiac vagal regulation and peer status. To assess cardiac vagal regulation, resting measures of respiratory sinus arrhythmia (RSA) and RSA change (suppression) to 3 cognitively and emotionally challenging tasks…
14. Cardiac cachexia: hic et nunc
Science.gov (United States)
Loncar, Goran; Springer, Jochen; Anker, Markus; Doehner, Wolfram
2016-01-01
Abstract Cardiac cachexia (CC) is the clinical entity at the end of the chronic natural course of heart failure (HF). Despite the efforts, even the most recent definition of cardiac cachexia has been challenged, more precisely, the addition of new criteria on top of obligatory weight loss. The pathophysiology of CC is complex and multifactorial. A better understanding of pathophysiological pathways in body wasting will contribute to establish potentially novel treatment strategies. The complex biochemical network related with CC and HF pathophysiology underlines that a single biomarker cannot reflect all of the features of the disease. Biomarkers that could pick up the changes in body composition before they convey into clinical manifestations of CC would be of great importance. The development of preventive and therapeutic strategies against cachexia, sarcopenia, and wasting disorders is perceived as an urgent need by healthcare professionals. The treatment of body wasting remains an unresolved challenge to this day. As CC is a multifactorial disorder, it is unlikely that any single agent will be completely effective in treating this condition. Among all investigated therapeutic strategies, aerobic exercise training in HF patients is the most proved to counteract skeletal muscle wasting and is recommended by treatment guidelines for HF. PMID:27386168
15. Cardiac cachexia: hic et nunc.
Science.gov (United States)
Loncar, Goran; Springer, Jochen; Anker, Markus; Doehner, Wolfram; Lainscak, Mitja
2016-06-01
Cardiac cachexia (CC) is the clinical entity at the end of the chronic natural course of heart failure (HF). Despite the efforts, even the most recent definition of cardiac cachexia has been challenged, more precisely, the addition of new criteria on top of obligatory weight loss. The pathophysiology of CC is complex and multifactorial. A better understanding of pathophysiological pathways in body wasting will contribute to establish potentially novel treatment strategies. The complex biochemical network related with CC and HF pathophysiology underlines that a single biomarker cannot reflect all of the features of the disease. Biomarkers that could pick up the changes in body composition before they convey into clinical manifestations of CC would be of great importance. The development of preventive and therapeutic strategies against cachexia, sarcopenia, and wasting disorders is perceived as an urgent need by healthcare professionals. The treatment of body wasting remains an unresolved challenge to this day. As CC is a multifactorial disorder, it is unlikely that any single agent will be completely effective in treating this condition. Among all investigated therapeutic strategies, aerobic exercise training in HF patients is the most proved to counteract skeletal muscle wasting and is recommended by treatment guidelines for HF. PMID:27386168
16. Cardiac involvement in rheumatoid arthritis
Directory of Open Access Journals (Sweden)
V. De Gennaro Colonna
2011-06-01
Full Text Available Rheumatoid arthritis (RA is a systemic disease of unknown etiology characterized by a chronic inflammatory process mainly leading to destruction of synovial membrane of small and major diarthrodial joints. The prevalence of RA within the general adult population is about 1% and female subjects in fertile age result mostly involved. It’s an invalidating disease, associated with changes in life quality and a reduced life expectancy. Moreover, we can observe an increased mortality rate in this population early after the onset of the disease. The mortality excess can be partially due to infective, gastrointestinal, renal or pulmonary complications and malignancy (mainly lung cancer and non- Hodgkin lymphoma. Among extra-articular complications, cardiovascular (CV involvement represents one of the leading causes of morbidity and mortality. Every cardiac structure can be affected by different pathogenic pathways: heart valves, conduction system, myocardium, endocardium, pericardium and coronary arteries. Consequently, different clinical manifestations can be detected, including: pericarditis, myocarditis, myocardial fibrosis, arrhythmias, alterations of conduction system, coronaropathies and ischemic cardiopathy, valvular disease, pulmonary hypertension and heart failure. Considering that early cardiac involvement negatively affects the prognosis, it is mandatory to identify high CV risk RA patients to better define long-term management of this population.
17. [Technologies for cardiac valve prostheses].
Science.gov (United States)
Nakano, Kiyoharu
2009-07-01
To show the technological development of cardiac valve prostheses, a historical review of both mechanical and biological valve prostheses and a current overview of modern cardiac valve devices are provided. Scince the 1st implantation of Starr-Edwards ball valve in 1960, both mechanical and biological valve prostheses have advanced. The valve design, the material of the leaflet and the hausing of mechanical prostheses have improved. Currently, the majority of the mechanical prostheses are bileaflet tilting disc valves made of pyrolytic carbon, which is antithromboembolic. However, anticoagulation therapy with warfarin is still required. As for the bioprostheses, although the fixation and anti-mineralization methods of the tissues improved, the durability of these valves is still limited. For the material of the current biological valves, the porcine aortic valve or bovine pericardium are used. The tissues are fixed by non-pressure or low-pressure method in glutaraldehyde solution. A stented and non-stented valves are available. Epoch-making events in this field are the implantation of new bioprosthetic valves using tissue engineering methods and the development of the transcatheter valve replacement therapies.
18. Cardiac Rehabilitation in Older Adults.
Science.gov (United States)
Schopfer, David W; Forman, Daniel E
2016-09-01
The biology of aging and the pathophysiology of cardiovascular disease (CVD) overlap, with the effect that CVD is endemic in the growing population of older adults. Moreover, CVD in older adults is usually complicated by age-related complexities, including multimorbidity, polypharmacy, frailty, and other intricacies that add to the risks of ambiguous symptoms, deconditioning, iatrogenesis, falls, disability, and other challenges. Cardiac rehabilitation (CR) is a comprehensive lifestyle program that can have particular benefit for older patients with cardiovascular conditions. Although CR was originally designed primarily as an exercise training program for younger adults after a myocardial infarction or coronary artery bypass surgery, it has evolved as a comprehensive lifestyle program (promoting physical activity as well as education, diet, risk reduction, and adherence) for a broader range of CVD (coronary heart disease, heart failure, and valvular heart disease). It provides a valuable opportunity to address and moderate many of the challenges pertinent for the large and growing population of older adults with CVD. Cardiac rehabilitation promotes physical function (cardiorespiratory fitness as well as strength and balance) that helps overcome disease and deconditioning as well as related vulnerabilities such as disability, frailty, and falls. Similarly, CR facilitates education, monitoring, and guidance to reduce iatrogenesis and promote adherence. Furthermore, CR fosters cognition, socialization, and independence in older patients. Yet despite all its conceptual benefits, CR is significantly underused in older populations. This review discusses benefits and the paradoxical underuse of CR, as well as evolving models of care that may achieve greater application and efficacy. PMID:27297002
19. Endogenous resident c-Kit cardiac stem cells increase in mice with an exercise-induced, physiologically hypertrophied heart
Directory of Open Access Journals (Sweden)
Camila Ferreira Leite
2015-07-01
Full Text Available Physical activity evokes well-known adaptations in the cardiovascular system. Although exercise training induces cardiac remodeling, whether multipotent stem cells play a functional role in the hypertrophic process remains unknown. To evaluate this possibility, C57BL/6 mice were subjected to swimming training aimed at achieving cardiac hypertrophy, which was morphologically and electrocardiographically characterized. Subsequently, c-Kit+Lin− and Sca-1+Lin− cardiac stem cells (CSCs were quantified using flow cytometry while cardiac muscle-derived stromal cells (CMSCs, also known as cardiac-derived mesenchymal stem cells were assessed using in vitro colony-forming unit fibroblast assay (CFU-F. Only the number of c-Kit+Lin− cells increased in the hypertrophied heart. To investigate a possible extracardiac origin of these cells, a parabiotic eGFP transgenic/wild-type mouse model was used. The parabiotic pairs were subjected to swimming, and the wild-type heart in particular was tested for eGFP+ stem cells. The results revealed a negligible number of extracardiac stem cells in the heart, allowing us to infer a cardiac origin for the increased amount of detected c-Kit+ cells. In conclusion, the number of resident Sca-1+Lin− cells and CMSCs was not changed, whereas the number of c-Kit+Lin− cells was increased during physiological cardiac hypertrophy. These c-Kit+Lin− CSCs may contribute to the physiological cardiac remodeling that result from exercise training.
20. Lesion Expansion in Experimental Demyelination Animal Models and Multiple Sclerosis Lesions.
Science.gov (United States)
Große-Veldmann, René; Becker, Birte; Amor, Sandra; van der Valk, Paul; Beyer, Cordian; Kipp, Markus
2016-09-01
Gray matter pathology is an important aspect of multiple sclerosis (MS) pathogenesis and disease progression. In a recent study, we were able to demonstrate that the higher myelin content in the white matter parts of the brain is an important variable in the neuroinflammatory response during demyelinating events. Whether higher white matter myelination contributes to lesion development and progression is not known. Here, we compared lesion size of intra-cortical vs. white matter MS lesions. Furthermore, dynamics of lesion development was compared in the cuprizone and lysophosphatidylcholine models. We provide clear evidence that in the human brain, white matter lesions are significantly increased in size as compared to intra-cortical gray matter lesions. In addition, studies using the cuprizone mouse model revealed that the autonomous progression of white matter lesions is more severe compared to that in the gray matter. Focal demyelination revealed that the application of equal amounts of lysophosphatidylcholine results in more severe demyelination in the white compared to the gray matter. In summary, lesion progression is most intense in myelin-rich white matter regions, irrespective of the initial lesion trigger mechanism. A better understanding of myelin debris-triggered lesion expansion will pave the way for the development of new protective strategies in the future. PMID:26363796 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.40188032388687134, "perplexity": 15003.289999830013}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-22/segments/1495463608665.33/warc/CC-MAIN-20170526124958-20170526144958-00228.warc.gz"} |
http://mathoverflow.net/questions/74115/explanation-of-a-proof-of-an-determinant-bound | Explanation of a proof of an determinant bound?
Let $A\in \mathbb{R}^{n\times n}$ be a positive definite symmetric matrix with eigenvalues $\lambda_1\ge \cdots\ge \lambda_n$, $X\in \mathbb{R}^{n\times k}$ such that $X'X=I_k$ ($X'$ means the transpose of $X$) and $n\ge 2k$, then $$\det(X'AXX'A^{-1}X)\le \prod\limits_{j=1}^k\frac{(\lambda_j+\lambda_{n-j+1})^2}{4\lambda_j\lambda_{n-j+1}}.$$
This result was first proved by Bloomfield and Watson(1975) and Knott(1975). I came across a note by H. Yang (A brief proof on the generalized variance bound of the relative efficiency in statistics, Communications in Statistics - Theory and Methods, 19(1990):12, 4587-4590), but the notation of his proof was rather confusing. Can any one make a clean proof or explain his proof?
(I don't have an e-version of that paper, sorry for inconvenience)
-
Here is a crude sketch that could work. First recall Hadamard's determinant theorem:
\begin{eqnarray*} |X'AX| \le \prod_{i}(X'AX)_{ii} = \prod_i x_i^TAx_i. \end{eqnarray*}
Now recall Kantorovich's inequality (for $x^Tx=1$ ) \begin{eqnarray*} (x^TAx)(x^TA^{-1}x) \le \frac{(\lambda_1 + \lambda_n)^2}{4\lambda_1\lambda_n} \end{eqnarray*}
Now, inductively apply this inequality to the product
\begin{eqnarray*} \prod_i x_i^TAx_i \end{eqnarray*} by using $x_i^Tx_j = 0$, if $i\neq j$, so that for example, we have \begin{eqnarray*} (x_1^TAx_1)(x_1^TA^{-1}x_1) &\le& \frac{(\lambda_1 + \lambda_n)^2}{4\lambda_1\lambda_n}\\\\ (x_2^TAx_2)(x_2^TA^{-1}x_2) &\le& \frac{(\lambda_2 + \lambda_{n-1})^2}{4\lambda_2\lambda_{n-1}}, \end{eqnarray*} and so on uptil $x_k$.
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It is not clear how you get \begin{eqnarray*} (x_2^TAx_2)(x_2^TA^{-1}x_2) &\le& \frac{(\lambda_2 + \lambda_{n-1})^2}{4\lambda_2\lambda_{n-1}}. \end{eqnarray*} – Sunni Sep 2 '11 at 0:18
Btw, did you read that article by Yang 1990? – Sunni Sep 2 '11 at 0:19
I have not yet worked out the details, but "it could work"; as for Yang, nope, I have not read any of the papers that you have cited; no time. – Suvrit Sep 2 '11 at 0:46 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9634769558906555, "perplexity": 2194.544361810725}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-14/segments/1427131298576.76/warc/CC-MAIN-20150323172138-00063-ip-10-168-14-71.ec2.internal.warc.gz"} |
https://aas.org/archives/BAAS/v25n4/aas183/abs/S11101.html | Magnetic Moments and Angular Momenta in Stars and Planets
Session 111 -- Stellar Interiors
Display presentation, Saturday, January 15, 9:30-6:45, Salons I/II Room (Crystal Gateway)
## [111.01] Magnetic Moments and Angular Momenta in Stars and Planets
N. Arge, D. J. Mullan (Bartol), A. Dolginov (LPI)
Using published data on magnetic fields, radii, masses, and rotation, we have compiled a dataset of magnetic moment $M$ and angular momentum $J$ for stars and planets. The stellar sub-sample extends from spectral class O to class M, with members of all classes represented. Among the hotter stars (classes A, B, and O), the sample includes 134 objects. For the cooler stars (classes F, G, K, and M), there are 33 objects. Our sub-sample of white dwarfs includes 33 objects, some in cataclysmic variables. The neutron star sub-sample contains 17 pulsars in binaries and 86 isolated pulsars. The solar system sub-sample contains seven planets plus the Sun. We find statistically significant positive correlations between log $M$ and log $J$ in the hot sub-sample and in the cool sub-sample: however, the slopes of the correlations are quite different for hot and cool stars. In the solar system sub-sample, the correlation has essentially the same slope as for the cool stars, although the intercept is almost two orders of magnitude smaller for the solar-system objects. For the isolated pulsars, we find no statistically significant correlation, while pulsars in binaries show a significant anti-correlation. Anti-correlation also appears in the white dwarf sub-sample, but this result relies heavily on five systems where rotational information is ambiguous.
\vskip0.2truein \noindent This work has been supported by NASA Grant NAGW-2456. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7283422946929932, "perplexity": 2748.6844549343573}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-36/segments/1471982954771.66/warc/CC-MAIN-20160823200914-00063-ip-10-153-172-175.ec2.internal.warc.gz"} |
http://geotech.chinaxiv.org/user/search.htm?field=keywords&value=Backscattering | Current Location:home > Browse
## 1. chinaXiv:201703.00309 [pdf]
Subjects: Geosciences >> Space Physics
Dual-frequency polarized scatterometer (DFPSCAT) is a pencil-beam rotating scatterometer which is designed for snow water equivalent (SWE) measurement, and Doppler beam sharpening (DBS) technique is proposed for DFPSCAT to achieve the azimuth resolution. However, the DBS technique is inapplicable for the forward-looking and afterward-looking regions. Based on an approximate aperiodic model of scatterometer echo signal, an improved adaptive regularization deconvolution algorithm with gradient histogram preservation (GHP) constraint is implemented to settle the problem. To investigate its performance of resolution enhancement and resulted accuracy, both a synthetic backscattering coefficient (σ0field reconstruction and SWE σ0reconstruction are carried out. The results show that the proposed method can recover the truth signal and achieve azimuth resolution of 2 km with the designed scatterometer system, which is required by the SWE retrieval. Moreover, the relative errors of reconstructed σ0are less than 0.5 dB that satisfy the accuracy requirement for SWE retrieval, and comparisons with observed results show that the error reduction is more than 0.03 dB. Meanwhile, a comparison between the proposed algorithm and some existing resolution enhancement methods is analyzed, which concludes that the proposed method can obtain a comparable resolution enhancement as L1method and has less noise. The technique is also verified with advanced scatterometer (ASCAT) scatterometer data. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9323904514312744, "perplexity": 3400.940031785319}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-50/segments/1606141195198.31/warc/CC-MAIN-20201128070431-20201128100431-00205.warc.gz"} |
http://www.computer.org/csdl/trans/tc/1988/07/t0815-abs.html | Subscribe
Issue No.07 - July (1988 vol.37)
pp: 815-825
ABSTRACT
A class of stochastic Petri nets called stochastic high-level Petri nets (SHLPNs) is proposed. SHLPNs are high-level Petri nets augmented with exponentially distributed firing times. SHLPNs generally lead to models with a smaller state space. A computer marking concept is introduced that allows a considerable reduction of the number of states and induces a correct grouping of states in the Mark
INDEX TERMS
stochastic high level Petri nets; models; computer marking concept; multiprocessor systems; directed graphs; multiprocessing systems; stochastic processes.
CITATION
C. Lin, D.C. Marinescu, "Stochastic High-Level Petri Nets and Applications", IEEE Transactions on Computers, vol.37, no. 7, pp. 815-825, July 1988, doi:10.1109/12.2227 | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8781038522720337, "perplexity": 8405.464329153658}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-27/segments/1435375093974.67/warc/CC-MAIN-20150627031813-00029-ip-10-179-60-89.ec2.internal.warc.gz"} |
http://mathhelpforum.com/pre-calculus/97751-f-x-x-1-3-a.html | # Math Help - f(x) = x^1/3
1. ## f(x) = x^1/3
ok so for this project I have to identify all this stuff for the function
$f(x) = x^{1/3}$
and a few things that I have to identify I don't know.
1) What are intervals of continuity?
2) Explain one-to-one
I have no idea what both those things are. Please explain for me so that I can understand.
Thanks!
2. Originally Posted by yoman360
1) What are intervals of continuity?
I think you are being asked to provide what interval fr x these function is continuous. As x can be any real number in this case then the interval for continuity would be $(-\infty ,\infty)$
Originally Posted by yoman360
2) Explain one-to-one
The term one to one means that there is only one x value for any y value (and vice versa) for the function in question.
3. yoman360, perhaps this graph may help you . . . .
Attached Thumbnails
4. Originally Posted by pacman | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 2, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9010801315307617, "perplexity": 772.1933152357735}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-22/segments/1464052946109.59/warc/CC-MAIN-20160524012226-00151-ip-10-185-217-139.ec2.internal.warc.gz"} |
http://www.physicsforums.com/showthread.php?p=4243077 | # Finding deflection and twisting using Castiglianos and Energy Methods
by Payam30
Tags: castiglianos, deflection, energy, methods, twisting
P: 23 Hi, This is not an homework. I'm doing a old exam question and have diffuclities. Since there is not a solution I want to get confirmed before I goes further with other similar question. I have the figure belove. The problem is here I do like this. Since I should have some bending moment I insert a fictive bending moment which is made by the force N. Then I do draw the forces in different part and solve the system. When I have N then I use the relation N = k.d where K is the stiffness coefficient of the spring. and then I solve for d. Forces R1 and R2 är equal since N is in the middle of the sctructure. But if I insert the fictive force They take other values right? or am I wrong? I wonder if this is the right wat to do these kind of problem. Please guide me! thanks :)
P: 100 Your solution is most likely wrong and too simplistic, I think. Did you apply that prescribed theta and the applied moment or was the part of the initial problem? I'm assuming that those were NOT part of the initial problem. I also assume that you were given more information than you are showing: e.x. E, I, L Pretty sure you can't solve this problem without knowing such things because the structure is statically indeterminate (there could certainly be horizontal reactions at those pins) Most likely, you are expected to use Castigliano's theorem in the following way: 1) Recognize that your structure is statically indeterminate to degree 1. 2) Change one of the pins to a roller, and replace the missing force with your own force, call it "H." 3) Find all of the moments in the frame as functions of x and y due to "H" and the applied load N (this is possible now since you have made your structure statically determinate). 4) Apply Castigliano's Theorem, which will involve taking the derivative with respect to "H," integrating your moments, etc. (you should know how to do this if you have learned Castigliano's theorem) 5) The motion in direction "H" is actually zero, so you use that constraint to obtain one equation, with one unknown, "H." 6) Since you now know "H," you can use static equilibrium to solve for any other forces of interest.. E.x. 1 at THIS LINK is a statically indeterminate problem of degree 2, if you want to study the procedure.
P: 23
Quote by afreiden Your solution is most likely wrong and too simplistic, I think. Did you apply that prescribed theta and the applied moment or was the part of the initial problem? I'm assuming that those were NOT part of the initial problem. I also assume that you were given more information than you are showing: e.x. E, I, L Pretty sure you can't solve this problem without knowing such things because the structure is statically indeterminate (there could certainly be horizontal reactions at those pins) Most likely, you are expected to use Castigliano's theorem in the following way: 1) Recognize that your structure is statically indeterminate to degree 1. 2) Change one of the pins to a roller, and replace the missing force with your own force, call it "H." 3) Find all of the moments in the frame as functions of x and y due to "H" and the applied load N (this is possible now since you have made your structure statically determinate). 4) Apply Castigliano's Theorem, which will involve taking the derivative with respect to "H," integrating your moments, etc. (you should know how to do this if you have learned Castigliano's theorem) 5) The motion in direction "H" is actually zero, so you use that constraint to obtain one equation, with one unknown, "H." 6) Since you now know "H," you can use static equilibrium to solve for any other forces of interest.. E.x. 1 at THIS LINK is a statically indeterminate problem of degree 2, if you want to study the procedure.
Hi Thank you for your help. Theta is given at the place I showed you. E and I and L are given.and mass of the thin = m and g =9.81 I didnt actully understand what you ment by the steps you represented. :(
P: 23
## Finding deflection and twisting using Castiglianos and Energy Methods
Anyone?
P: 23 When I do as you say. I get a vertical force too. and I will have N, V and H. is N =mg?
P: 100
Quote by Payam30 When I do as you say. I get a vertical force too. and I will have N, V and H. is N =mg?
Not sure what N,V,H you are referring to, but the "N" I was talking about was consistent with your "N" from your first post - N=k*d.
If you are expected to give a solution in terms of the given angle, then you should do so, in which case you still do my six steps, but instead of "H," you'll have "M." This is sort've what you drew in your original post. However, you ought to split up your structure into two parts: the beam, and the column. Apply the M equal and opposite onto each piece. Go through my steps. Your final solution would be in terms of the angle change.
If you think that my method is too complicated, can you ask a real life person who is familiar with your particular class?
P: 23 I will post my solution here so you can see if I do something wrong. becouse the total energy is too complicated now! and the derivation will not give a good solution. I paste my solutions here so you can tell me where do I do wrong. Yes but I already send an email but not response yet. Im expected to determine deflektion theta in the spring and the rotation in theta..where I showed it from beginning
P: 100 Doesn't look like you're using Castigliano's method like you said in the title.. or did you just skip the step where you write down the integrals? Regardless of what method you are using, however (Castigliano's method, moment distribution method..), you should be able to solve for everything in terms of theta and the spring deflection without splitting the structure into so many different segments.. why don't you just split it into two segments -- the beam and the column?
P: 23 I don't know how to do that Could you please write down what you mean? in mathematical terms
P: 100 Look at the link in my first post. If you take the time to understand that problem, then you will be able to do your problem.
P: 23
Quote by afreiden Look at the link in my first post. If you take the time to understand that problem, then you will be able to do your problem.
Im running ubuntu and it has some problem with the link. Can we talk in private message?
P: 23 I just can't get it work sorry.!
P: 23 Could you please just draw the figure you are thinking about?
P: 23 H vill not give a moment in the x axis.. I dont know how you mean. and I saw the file... I will get problems
Related Discussions Introductory Physics Homework 9 Mechanical Engineering 3 Engineering, Comp Sci, & Technology Homework 3 Engineering, Comp Sci, & Technology Homework 1 Engineering, Comp Sci, & Technology Homework 2 | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8937445878982544, "perplexity": 555.7710373542237}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2013-48/segments/1386164047228/warc/CC-MAIN-20131204133407-00027-ip-10-33-133-15.ec2.internal.warc.gz"} |
http://www.blog.republicofmath.com/the-rascal-triangle-how-magic-can-happen-if-you-listen-to-kids/ | # The Rascal Triangle: how magic can happen if you listen to kids
Posted by: Gary Ernest Davis on: January 8, 2011
Three middle school students, widely geographically separated, worked together to produce a novel piece of mathematics of interest.
The students, shown above, are (from left to right):
• Alif Anggoro, a seventh grader at Al Azhar Junior High School in Java Bekasi, Jakarta, Indonesia
• Eddy Liu, an eighth grader at Washington Middle School, Seattle, Washington, USA
• Angus Tulloch, an eighth grader at Crestomere School in Rimbey, Alberta, Canada
The results of their original work are here: The_Rascal_Triangle
In this post I want to discuss what they did, how they came to do it, and what lesson their might be in their experience for mathematics education.
This is a perfect story to report on in the Republic of Mathematics, because it shows that when kids are listened to they can have tremendous fun working out their own ideas.
It also shows that just because someone is young and in middle school does not mean that they cannot think with maturity, given half a chance.
#### What did they do?
These three middle school students built a version of Pascal’s triangle – which they named The Rascal Triangle – by using a different rule for producing numbers in a row of the triangle from the row above.
In Pascal’s triangle the entries, other than the 1’s, are obtained from the two entries above, to the left and right, by addition:
First 5 rows of Pascal's Triangle
Pascal’s triangle does not stop at row 5, but goes on forever.
The general scheme for determining entries in Pascal’s triangle, other than the outside 1’s, can be represented as follows:
The rule for generating Pascal's Triangle
Alif, Eddy and Angus came up with a different rule for determining entries in the otherwise blank triangle:
This generates the Rascal Triangle:
First 5 rows of the Rascal Triangle
Like Pascal’s Triangle, the Rascal Triangle does not stop at row 5 but goes on forever.
However, unlike Pascal’s Triangle, the middle entry in row 5 of the Rascal Triangle is 5, not 6.
The challenge for the students was to show that the entries in this Rascal Triangle are whole numbers, which is not at all obvious from the generating rule for the Rascal Triangle.
A fuller version of the Rascal Triangle shows an interesting pattern along the diagonals:
Patterns along the diagonals of the Rascal's Triangle
The $2^{nd}$ diagonal, for example consists of the numbers 1, 3, 5, 7, 9, 11 … Starting from 1, these numbers are spaces 2 apart.
The $3^{rd}$ diagonal consists of the numbers 1, 4, 7, 10, 13, … . Starting from 1, these numbers are 3 spaces apart.
The $4^{th}$ diagonal consists of the numbers 1, 5, 9, 13 … Starting from 1, these numbers are 4 spaces apart.
It’s a decent guess, therefore, from as much of the Rascal Triangle as we can see, that the entries on the $m^{th}$ diagonal are $1, m, 1+2m, 1+3m, 1+4m, 1+5m, \ldots$.
If we count the beginning 1 in this sequence as the $0^{th}$ term then this guess as to the diagonal entries would say that the $n^{th}$ term on the $m^{th}$ diagonal is $m\times n +1$.
If this guess is correct then the Rascal Triangle does indeed have only whole number entries.
To establish this pattern guess is indeed correct, imagine a triangle in which, in fact, the $n^{th}$ term on the $m^{th}$ diagonal is $m\times n +1$. In particular, the beginning entry in each diagonal is 1.
We can show this must be just the Rascal Triangle if we can show that such a triangle has the same generating formula as the Rascal Triangle.
In the diagram above, suppose that the $c$ entry is the $n^{th}$ entry on the $m^{th}$ diagonal, so that $c=mn+1$.
Then $a$ is the $(n+1)^{st}$ entry on the $m^{th}$ diagonal, so $a=m(n+1)+1$.
Also, $b$ is the $n^{th}$ entry on the $(m+1)^{st}$ diagonal so $b=(m+1)n+1$.
And finally, the ? entry is the $(n+1)^{st}$ entry on the $(m+1)^{st}$ diagonal so $?=(m+1)(n+1)+1$.
Then,
$\frac{a\times b+1}{c}=\frac{(m(n+1)+1)\times ((m+1)n+1)+1}{mn+1}$
$=\frac{(mn+m+1)\times(mn+n+1)+1}{mn+1}$
$= \frac{m^2n^2+m^2n+mn^2+3mn+m+n+2}{mn+1}$
$= \frac{mn(mn+1)+m(mn+1)+n(mn+1)+2(mn+1)}{mn+1}$
$=mn+m+n+2 = (m+1)(n+1)+1=?$
so , indeed the Rascal generating rule holds for this triangle, so it IS the Rascal triangle, and therefore the Rascal Triangle has whole number entries
#### Why did they do it?
In the write-up of their joint work the students construct a hypothetical scenario in which a teacher gives them an “IQ test” question to fill in the $5^{th}$ row of a triangle by guessing the pattern from the previous rows.
The students guess the middle term of the row is 5 because they have a rule that corresponds to the Rascal Triangle.
The hypothetical teacher then says that this rule is complicated and anyway may not give whole number answers, so the students set out to show that whole number answers result.
In fact, the real situation was quite different.
Liu is an eighth-grader at Washington Middle School in Seattle, Washington. He served as the corresponding author for the paper. Tulloch is an eighth-grader at Crestomere School in Rimbey, Alberta. Anggoro, a seventh-grader at Al Azhar Junior High School in Java Bekasi, a suburb of Jakarta, Indonesia, has never met his fellow authors. Their collaboration was conducted via email.
Mathematician Andy Liu (University of Alberta) orchestrated the collaboration. Eddy Liu, Andy’s nephew, first met Tulloch at a mathematics summer camp in Edmonton in 2008. “I met Alif in Manila during the First East Asian Mathematics Summer Camp in 2009,” Andy Liu wrote in a recent email. “At that time, Eddy and Angus had been working on the triangle problem. However, like typical North America cars, their engines were not highly charged, but their brakes were mighty powerful. So I suggested to Alif to contact both Eddy and Angus, which he took the initiative to do so.” (Mathematical Association of America, 2010)
#### What lessons are there for mathematics education?
The MAA web page indicates that Andy Liu had a strong hand in guiding the students to work together.
What is not clear from that account, or from the students final article, is how they really came to work on the problem, and how much help Eddy Liu’s uncle Andy gave along the way.
After reading the published article I believe that a relatively sophisticated mathematician wrote most of the argument. This is not to say that the students did not come up with, or understand, the argument. However, the language is, in my experience quite sophisticated for middle school students, the algebra is quite complicated for middle school students, and the argument to show that two inductively defined objects are equal when the satisfy the same generating formula and the same boundary conditions is very sophisticated for school students.
I would dearly like to know the dynamics of the solution to this problem because it is a beautiful example of what can motivate students in mathematics.
It is a lovely example of how much fun school mathematics can be if a teacher – in this case probably uncle Andy Liu – listens to students and encourages and nurtures their ideas.
What tremendous pride these 3 students must feel to see their work written up in print for the world to see.
Congratulations to them and uncle Andy Liu on a beautiful example of how middle school students can do interesting mathematical research.
### 6 Responses to "The Rascal Triangle: how magic can happen if you listen to kids"
[…] This post was mentioned on Twitter by A Swash, Egan J Chernoff. Egan J Chernoff said: The Rascal Triangle: how magic can happen if you listen to kids: http://t.co/1tggJqp […]
It would be interesting to know more about the background and development of the work as you pointed out Gary. However, I believe the middle school students could have developed the argument even with its sophistication. I work with students this age a lot and I could see them describing the patterns, but not in mathematical notation. I think with the right prompting questions and examples of similar notation they could have put it together. The article seems to have the structure of writing that I’d expect from more sophisticated middle school students that had received feedback along the way.
Whatever the level of support, definitely the type of mathematic activity that I want to create more of in my class. Very inspiring, thanks for pointing it out.
[…] which also generates an infinite series of whole numbers. I’ll let Gary E. Davis, at the Republic of Math, illustrate the rule, since I’m not a mathematician. As Davis notes, “It is a lovely […]
It’s pretty good for eighth graders, but I wish they had done more with it. The triangle is just a rotated multiplication table with one added to each entry. Do you get a similar generating formula if you add 2 to each entry of a multiplication table?
[…] post was inspired by The Rascal Triangle which I read a couple of days after engaging in this […]
Andy Liu saw something pretty special in all three of these smart youngsters. Encouraging them to collaborate across the world via e-mail towards a common goal is pretty amazing. Reading this has inspired me to share the article with my students. With enthusiasm, I will assure them that our classroom is a positive environment that provides nourishment and support towards new ideas. My hope is that the article will motivate and inspire students to take risks and to create something as equally awesome as these three students. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 33, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6497371792793274, "perplexity": 1059.795564321799}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-31/segments/1627046153966.52/warc/CC-MAIN-20210730091645-20210730121645-00094.warc.gz"} |
http://mathhelpforum.com/differential-geometry/155288-proof-involving-archimedean-property.html | # Math Help - Proof involving the Archimedean property.
1. ## Proof involving the Archimedean property.
Given any x $\in$ R prove that there exists a unique n $\in$ Z such that n - 1 $\leq$ x < n.
Proof: Suppose x $\in$ R. By the Archimedean property, there is an n $\in$ Z such that n > x. Since N is well-defined, we have that n - 1 $\in$ N and n - 1 < n. Then it follows that n - 1 $\leq$ x < n for x $\in$ R.
I feel like I've jumped to conclusions, but to my non-math-genius brain, I feel like this is correct. Can someone prod me along?
2. Originally Posted by mjlaz
Given any x $\in$ R prove that there exists a unique n $\in$ Z such that n - 1 $\leq$ x < n.
Proof: Suppose x $\in$ R. By the Archimedean property, there is an n $\in$ Z such that n > x. Since N is well-defined, we have that n - 1 $\in$ N and n - 1 < n. Then it follows that n - 1 $\leq$ x < n for x $\in$ R.
I feel like I've jumped to conclusions, but to my non-math-genius brain, I feel like this is correct. Can someone prod me along?
Your error is in asserting that n-1< x. The Archimedean property only tells you that there is an integer larger than x. it does not tell you that that integer is anywhere near x. For example, if the x= 1.5, the Archimedean property might be telling you that the number 1,000,000 is larger than 1.5.
You will also need to use the "well ordering property" of the positive integers: every non-empty set of positive integers contains a smallest member. Apply that to the set of all integers larger than x which the Archimedean property tells you is non-empty.
Proof: Let x $\in$ R. By the Archimedean property, there exists some n > x, n $\in$ Z. Define S = { y $\in$ Z : y > x}. Since S is bounded below by x, then by the well-ordering principle of integers, there is a least element in S, namely n = min(S). Since n $\in$ S, then n > x. However, n - 1 $\notin$ S and so n - 1 $\leq$ x < n.
I haven't proved the uniqueness component.
4. Originally Posted by mjlaz
I haven't proved the uniqueness component.
Is it not the case that a least element (from well ordering) is unique?
5. Allow me to give you a different proof.
You need the completeness axiom.
We need to have proved that the set of integers, $\mathbb{Z}$, is not bounded.
If $a\in \mathbb{R}$ the define $\mathcal{S}=\{n\in \mathbb{Z}:n\le a\}$.
Clearly we can say that $b=\sup(\mathcal{S})$.
Also $\left( {\exists c \in \mathcal{S}} \right)\left[ {b - 1 < c \leqslant b \leqslant a} \right]$.
From which we get $b < c + 1 \leqslant b + 1$ which means that $c + 1 \notin \mathcal{S}\, \Rightarrow \,a < c + 1\, \Rightarrow \,c \leqslant a < c + 1$.
That completes the proof. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 29, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9147664308547974, "perplexity": 285.7494174637324}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-52/segments/1419447549705.144/warc/CC-MAIN-20141224185909-00052-ip-10-231-17-201.ec2.internal.warc.gz"} |
http://www.jntumaterials.com/jntuh-ettl-model-papers-and-important-questions/ | Home » 2nd Year » JNTUH ETTL MODEL PAPERS AND IMPORTANT QUESTIONS
# JNTUH ETTL MODEL PAPERS AND IMPORTANT QUESTIONS
jntumaterials.com
DEPARTMENT OF
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper-1 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
Time: 3 hours Max. Marks: 75 PART- A (25 Marks) 1. a. State and Express the Coulomb‟s Law. (2M) b. Derive the Possion‟s and Laplace Equations for electrostaticfield. (3M) c. State and Express the Biot-Savart‟s Law. (2M) d. Writedown the Maxwell‟s Equations in word statement. (3M) e. Define the Uniform Plane wave. (2M) f .Define the Surface Impedance. (3M) g.Define the characterstic impedance. (2 M) h. Define the phase velocity. (3 M) i. Define the Reflection Coefficient (2 M) j. Explain the losses in transmission Line. (3 M)
PART-B (5*10=50
Marks)
2. a. State and Prove Gauss‟s Law.
b.Let = 400Sinθ/(r2+4) ar A/m2.
Find the total current flowing through that portion of the
spherical
surface r=0.8 bounded by 0.1
<θ<0.3π ,0<<2π.
OR
3.a. Show That = ρ
b.Given The Flux density D=16/r cos(2θ) c/m2,
Find the total charge with in the region 1<r<2m, 1<
4.
a.State The Law required to calculate magnetic flux density or magentic field
intensity for a
given
current or current distribution and derive the expression for the same.
b.Derive the conditions at boundary
surface of Dielectric-Dielectric interface?
OR
5.a. Define and Explain Ampere‟s circuit Law.
b.State Maxwell‟s Equations in Differential and Integral form with clear statement
6.
a. Derive the equation
for uniform plane wave in terms of H.
b. A
100MHz uniform plane wave Propagates in a lossless medium for which
r=5
and µ
r=1
find
vp,β,λ,Es,Hs.
OR
7. a. State and Prove the Pointing Theorem
b. Write short Notes on
i)Surface impedance ii) Brewster Angle
8.
a. Derive The Expression
for Transmission Line Equation. b.
Given R = 10.4
Ω/mt
L
= 0.00367 H/mt
G
= 0.8×10
-4
mhos/mt
C
= 0.00835 µF/mt.
Calculate
Z
0
and at 1.0
KHz
.
OR
9.Derive the expression
for α and β in terms of primary constants of a line
10.a) Establish the relations for Zsc and Zoc of rf lines and sketch their variation with
βl
b) A 60ohm lossless line
is 30m long and is terminated with a load of 75+j50ohms at 3MHz
find its
reflection coefficient,VSWR,if the line velocity is 60% of the velocity of
light
OR
11. a) Explain the principle of single
stub matching. b)Calculate the skin depth for the following conditions.
i) Copper f=1010Hz,µ=µ0,
σ=5.8×10
7s/m
jntumaterials.com
DEPARTMENT OF
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper-2 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
Time: 3 hours Max. Marks: 75 PART- A (25 Marks) 1. a. Define Electric Potential and Ploarization (2M) b. Define Capacitance? Explain different types of capacitances (3M) c. State and Express the Amperes circuit Law (2M) d. Define the boundary condition? Give the relations for electric field (3M) e. Define Brewster Angle (2M) f. Define Polarization? Explain different types of polarization (3M) g. Define the Propagation constant in terms of primary constants (2M) h. Define the group velocity (3M) i. Define the stub? (2M) j. Write down the Applications of Smith chart (3M) PART-B (5*10=50 Marks) 2.a. State and prove the coulomb‟s law ?
b. Find
the force on a charge of -100mC located at P(2,0,5) in free space due to
another charge 300µC located at Q(1,2,3).
OR
3. a. State and
Prove Laplace‟s and Poissson‟s Equation Starting from
Gauss‟s Law
b. The potential
field V=2x
2yz-y3z
exists in a dielectric medium having ε=2ε
0 calculate
. the
total charge within the unit cube 0<x<1m,0<y<1,0<z<1m.
4.a. Define Ampere‟s Circuit Law in point
and integral forms for Static fields.
b.
Establish the fields in the different regions of a coaxial cable carrying a
current I, and sketch their variation with radial distance.
OR
5. a.State and Prove Boundary condition between Dielectric-Dielectric
b. A Potential field is given by V=15(x2-y2).The
point p(4,-2,1) lies on the boundary of the conductor and free space At P,
obtain the magnitudes of i) V ii) E iii) E
N
iv) E
tan
v)D vi) ρ
s
6. a. Derive The
attenuation and phase constant in conducting medium
b. At 50MHz, a lossy dielectric
material is characterized by ε=3.6ε
0, µ=2.1µ0 and σ=0.08S/m. If
Es=6e
-ϒxazV/m, compute i) ϒ ii) λ iii) u
iv)η v) H
S
OR
7. a.Derive Expression for reflection and transmission coefficients of an EM wave
when it is incident normally on a dielectric
b. A perpendicularly polarized wave is
incident at an angle of ө
i=15degrees.
It is propagating from medium1 to medium2 .medium 1 is defined by ε
r1=8.5,μr1=1,σ1=0
and medium 2 is free space if E
i=1mv/m,
determine E
r,
H
i,
H
r
8. a. Derive The Condition
for Distrotionless Transmission Line
b. Measurements on a Transmission Line
of length 120Km were made at frequency of 6000Hz.If Z
OC=520(-30deg)
and Z
SC=640(43deg)
find Z
o
and P.
OR
9. a. Derive The Basic
Transmission Line Equation
b.The propagation constant of a lossy transmission line is 1+j2 m-1 and its
characteristic impedance is
20+j0Ω
at ω= 1rad/s. Find R,C,L,G for the Line.
10.a.Derive the relation between reflection coefficient and characteristic impedance
b. Write short notes on smith chart
OR
11.A transmission line of
length 0.40λ ? has a characteristic impedance of 100Ω and is Terminated in a
load impedance of 200 + j180ω. Find the
(a) Voltage
reflection coefficient
(b) Voltage
standing wave ratio
(c) Input
impedance of the line.
jntumaterials.com
DEPARTMENT OF
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper-3 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
Time: 3 hours Max. Marks: 75 PART- A (25 Marks) 1.a.Define Electric field and Electric flux Density (2M) b. Define Electric dipole? Differentiate between polar and non polar dielectrics (3M) c. State and Express the Stokes Theorem (2M) d. Write down the Maxwell‟s equations in free space condition (3M) e. Define Skin depth or Depth of penetration (2M) f. State and Express the Poynting theorem (3M) g. Write down the Distortionless Line (2M) h. Define Transmission line? Explain different types of Transmission lines (3M) i. Define the voltage Standing Wave Ratio (2M) j. Difference between the single stub matching and double stub matching (3M) PART-B (5*10=50 Marks) 2. a. Define Line charge Density? Derive the infinite line Electric field E=ρL/2 aρ b. Find E at(2,0,2) if a line charge of 10PC/m lies along the y-axis OR
3. a.
Define Capacitance and obtain the parallel plate capacitance
b. A parallel plate capacitance has 500mm side plates of square shape separated by
10mm distance A sulphur
slab of 6mm plates with ε
r=4
kept is on the lower plate find the capacitance of the set up If a voltage of
100V is applied across the
capacitor calculate the voltages at both
the regions of the capacitor between the plates.
4 .a. Derive an expression for magnetic
field strength,H,due to a finite filamentary conductor carrying a current I and
placed along Z-axis at a point „P‟ on Y-axis. Hence deduce the magnetic field
sgtrength for the length of the conductor extending -∞ to +∞.
b. State and
Prove Biot-Savart‟s Law.
OR
5.a.What is the inconsistency of Ampere‟s Law
b.A certain material has σ=0 and εr=1 if H=4sin(106t-0.01z) A/m.
Make use of
Maxwell‟s equations to find µr.
6. a. Show that E and H are
perpendicular to each other inphase and the ratio of their Magnitudes is a
constant for a uniform plane wave.
b.
A uniform plane wave at
a frequency of 1GHz is travelling in a large block of teflon
εr=2.1,µr=1
andσ=0. Determine ϒ,η,β,λ.
OR
7. a.Define Polyting’s theorem and Polyting Vector.
b. A Sinsoidally varying EM wave in a medium of εr=1
µ
r=1
is transmitting power at a density 1.2watts/m
2
.Find the maximum values of E and H fields.
8.Explain the
conditions which are used for minimum attenuation in transmission lines
OR
10.a. Derive the expression for the
input impedance of a transmission line of length L. b. List out the
applications of transmission lines
OR
11
.Describe the construction of smith chart and give its applications.
jntumaterials.com
DEPARTMENT OF
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper-4 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
Time: 3 hours Max. Marks: 75 PART- A (25 Marks) 1.a. State and Express the Divergence theorem (2M) b. A charge of 10PC is at rest in free space.Find the potential at a point, A 10cm away from the charge. (3M) c. A magnetic field, H=3ax+2ay,A/m exists at a point in free space, what is the magnetic flux density at the point (2M) d. Explain the different types of medium (3M) e. Define the Good Conductor (2M) f.Differences between intrinisic impedance and surface impedance (3M) g. Define the characterstic impedance in terms of the open circuit and short circuit impedance (2M) h. Define and Explain the infinite Line (3M) i. Define the smith chart (2M) j. Write downthe relation between reflection coefficient and voltage standing wave ratio (3M) PART-B (5*10=50 Marks)
2.a .State coulomb‟s and derive the
expression for coulomb‟s law to calculate the magnitude of The force between
two charges
b.Prove the poisson‟s equation for Electrostatic field
OR
3.a.Distinguish between the conduction
and convention currents. Establish the current Continuity equation and hence
calculate the relaxation time for brass material, having Conductivity of 1.1×10
7mho/m
at 10MHz.
b.Find the capacitance of a 50cm.long
coaxial cable, having conductors of 4cm and 2cm diameters, separated by a
medium of a relative permittivity 2.56.
4.a.Define Inductance? Derive the toroid inductance
b.A toroid has air core and has a
cross-sectional area of 10mm
2.It
has 1000turns and its mean radius is 10mm.Find its Inductance
OR
5.a.Obtain the integral form of Maxwell‟s equation from Amperes circuit law in the
generalized form
b. In a medium of µr=2,
find E,B and displacement current density if H=25sin(2×10
8t+6x)
mA/m
6. a.For good dielectrics derive the expressions for α,β,ϒ,η
b. A plane wavetravelling in a medium of εr=1,µr=1
has an electric field intensity of
v/m.Determine the energy density in the
magnetic field and also the total energy density.
OR
7.a Derive Expression for
reflection and transmission coefficients of an EM wave when it is incident
normally
on a dielectric.
b.A perpendicularly polarized wave is incident at an angle of өi=15degrees.
It is is free propagating from medium1 to medium2 .medium 1 is defined by
ε
r1=8.5,μr1=1,σ1=0 and medium2 space if Ei=1mv/m, determine Er, Hi,
H
r.
8.a.Derive the attenuation constant and
phase constant in terms of primary constants b.Explain different types of
OR
9.a.Derive the characteristic impedanceof a transmission line in terms of its line constants
b.At 8MHz thecharacteristic impedance of a transmission line as 40-j2ohms and the
propagation
constant 0.01+j0.18 per meter.Find the primary constant.
10.Explain the principal of single stub matching
OR
11. a.Derive the relation between reflection coefficient and characteristic impedance
b. write short notes on smith chart.
jntumaterials.com
DEPARTMENT OF
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper-5 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
Time:
3 hours
Max.
Marks: 75
PART- A (25 Marks) 1.a.The force F=2ax+ay+az N, is acting on a charge of 10C, find the electric field Intensity,its magnitude and direction. (2M) b.The current density J=1/r2(cosӨar+sinӨ ),A/m2, find the current passing through a sphere radius of 1m (3M) c.Given magnetic flux density,B=ρ ,find the total flux crossing the surface 1<ρ<2m and 0
PART-B (5*10=50
Marks)
2.a.State and Explain Coulomb‟s law.
b.Three point charges Q1=0.5nC,Q2=0.4nC, Q3=-0.6Nc are located in free space
at(0,0),(3,0)and(0,4)respectively.Determine the potential,electricfield
intensity and flux density at (3,4).
OR
3. a.
Determine the amount of work necessary to assemble three point charges Q1,
Q2,Q3 in an empty space. Extend your result to n-point charges.
b. Show that = ρ .
4.
a. State and Prove the Ampere‟s Force Law.
b.A toroidal ring has 200turns. The outer diameter of the ring is 15cm with the
inner diameter of 12cm.Find the flux density if the current is 8A.
5.
a. State and explain boundary conditions between two dielectric media.
b. A circular loop conductor having radius of 0.2m is placed in XY plane. The loop
consists of a resistance of 10ohms. If the Magnetic field is B=Sin10
4t
Tesla, find the current flowing in the loop.
6. a.Discuss the significance of pointing theorem and derive the equation for pointing Vector.
b.A vertically polarized uniform plane wave is incident at an angle of 450
from air on a dielectric slab of ϵ
r=4,µr=1 and σ=0.the incident field strength is 100mV/m at 10MHz.Calculate the power transmitted to the dielectric slab Find the angle of incidence for which angle of reflection is zero.
OR
7.a.Derive the equation for uniform plane wave in free space condition.
b.The electric field in free space is given by E=50cos(108t+βx)ayV/m.Find
the direction of wave propagation.Calculate β and time it takes to travel a
distance of λ/2
8. Derive the equation for input
impedance of the Eighth-Wave(λ/8) line? Explain Its significance
OR
9.
Write Short notes on
i) Smith
Chart
ii)Single stub matching
10.a.Derive an expression for thepropagation constant and characteristic impedance of Transmission line withR,L,C,G.
b. A telephone line has
R=30Ω/km, L=100Mh/km, G=0,C=20µF/km. At f=1KHz,obtain i) Z
0
ii) propagation constant iii ) phase velocity
OR
11.a. Derive an expression for the input impedance of a lossless line of length „l‟
in
Terms of Z0, β,Zand l when terminated by a Zload.
b. A lossless transmission line length
„l‟ with Z
0=50
is terminated by a load of Z
L=50+j50.Determine
the reflection coefficient “R
r
and the standing wave
Ratio.
.
Tags: Electromagnetic Theory and Transmission Lines Important Questions JNTUH R13 | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9069046974182129, "perplexity": 8530.27305090019}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-47/segments/1542039741294.2/warc/CC-MAIN-20181113062240-20181113084240-00198.warc.gz"} |
http://mathematica.stackexchange.com/tags/webmathematica/hot | # Tag Info
16
Maybe it is worth mentioning that webMathematica sites can be viewed without downloading and installing the 197 MB plugin. A lot of users (in companies, banks, institutions) just are not allowed to install anything at all and IT departments do not like big uncertified plugins. Furthermore a webMathematica page you can view on a any tablet or mobile phone. ...
14
Depending on the total size of the files, CDF may or may not be a good option. A file of a few MB is probably still ok, 10Mb or more is probably not. That said, this looks like a case for WebMathematica to me. It is fairly easy to set up, and looking at your description, you won't need an awful lot of interactivity (which, had you needed it, would be one ...
11
What you did with setting the "com.wolfram.jlink.libdir" property will work. Perhaps you didn't enter the correct path, or you used the wrong JLinkNativeLibrary.dll file (meaning you used the 32-bit one from JLink/SystemFiles/Libraries/Windows, instead of the 64-bit one from JLink/SystemFiles/Libraries/Windows-x86-64, or vice-versa). But you really ...
10
You cannot use CDF for this because you have textual import fields and these are not supported when you embed online. You will just get a big grey box. InputField cannot accept strings (non-numeric) for online CDFs unless you are Wolfram Research and can override it. (I'm guessing you don't want to pay many thousands for CDF Pro.) You also cannot import and ...
9
Here are the two ways I have successfully used MongoDB with Mathematica. AFAIK much of this would also apply to similar DBs such as CouchDB. A. Easy way One working example used a third party Mongo supplier such as 28msec.io and use URLFetch e.g. With this supplier you can both read from and write to the database using HTTP GET and simple query strings. ...
7
The different HTML entities are stored in SystemConvertMLStringDataDump$HTMLEntities on version 9 and from here, it's a simple StringReplace: StringReplace["<select></select>", SystemConvertMLStringDataDump$HTMLEntities] (* "<select></select>" *)
6
Something like: ExportString[Cell[TextData["<select></select>"],"Text"],"HTML","FullDocument" -> False] produces: <p class="Text"> <select></select> </p> which might also be a good start.
6
You probably shouldn't put that package into the $InstallationDirectory, there are$BaseDirectory for system wide installations of packages and $UserBaseDirectory for user specific installations (As Alexey Popkov has indicated these did supersed$AddOnsDirectory and $UserAddOnsDirectory of earlier versions. These still exist for compatibility, but probably ... 5 Since it appears that you wish to use live input for your Timeline, webMathematica will be the best solution. CDF cannot accept anything but input from what is in the file itself. Documentation can be found here: http://www.wolfram.com/products/webmathematica/ User Guide is located here: ... 5 In this case, I assume you want both, dynamic interactivity and pull large datasets from a database in real time. This can be done with a CDF notebook, and it doesn't require WebMathematica unless your notebook really needs to do much more computationally intensive work than your example code indicates. So here are the steps: Server Save your dynamic ... 5 Trigger an external event Edit Don't you dare to close this question! :) I've to say, that for the Java/MathPackage part of this answer I've used Workbench plugin within eclipse/Juno and again I've to agree with @halirutan that this is not a time saver at all. It took me more time to configure this etc. than to write the code. I am already a user of the ... 5 "Any engine compatible with Servlet 2.4 or later, such as Apache Tomcat" http://www.wolfram.com/products/webmathematica/technology/?tab=Specifications I really don't know much about Geronimo, but it seems to support servlet 2.5 (via Tomcat.) 4 There is no need to use Javascript to include CDF in a web page. Upload the CDF file (source.cdf) and the HTML page (index.htm) into a folder on the server. Keep both files in same folder for simplicity. Edit the index.htm file using a text editor and type this line in the HTML anywhere you want the CDF to show up and play in the web page: <embed ... 4 In webMathematica there is already MSPGetMessage[] So if you do something like mess = MSPGetMessages[]; you have a list of messages. E.g., if you had an error for 1/0 "1\nPower::infy: Infinite expression - encountered.\n 0" Notice that$MessageList gives just {HoldForm[Power::infy]}
3
The answer depends on what you want to do with CDF documents. The standard version of Mathematica allows you to make CDF documents. A good example of what they can do is the stuff on demonstrations.wolfram.com. Basically, if you are content with making Manipulate statements with sliders and buttons, then you'll do well with the standard CDF document. You ...
3
you can try to add the dll to your path list. Window->Preferences->Java->Installed JREs. Then choose your current JRE(JDK) or the one you are using and click Edit. Fill Default VM Arguments: -Djava.library.path="the pathhhh of dll" or Under Linux set LD_LIBRARY_PATH. Under Windows set PATH.
3
You could use a trigger in your database which fires when data is added or changed in your table to execute a piece of code; I don't know sqlserver but I assume that a trigger can execute some c++ or .Net code. That in turn could pass the data into Mathematica through NetLink. Mathematica would have to be set up to listen for the data of course. Actually ...
2
No. But Dynamic and Button and so on just are not and cannot be supported. However, you can programmmatically generate CDF files, and put them onto your server. And in CDF's, when run through the CDF-plugin (on a Windows or OSX client; no Linux yet unfortunately) you can have Button etc.
2
Put a 2 in MSPConfiguration.xml like explained here <KernelNumber> 2 </KernelNumber> and then your kernels are used efficiently in that sense that if one kernel is busy serving one request, then another one is available if another request happens at the same time the first kernel is still running.
2
There is no problem importing base-64 encoded images into Mathematica. Here is an example: a = Import["ExampleData/rose.gif"]; Export["a.b64", a, {"Base64", "PNG"}]; Import["a.b64", "Base64"] The data that you create with your JavaScript function are in the form of a URL that then gets translated by a browser to a displayed PNG image. You have to strip ...
1
This seems to work. I think this sort of thing is probably dangerous -- well, unreliable. file = DataPacletsGetDataPacletResource["CountryData", "CountryData.wdx"]; DataPacletsCountryDataDump`\$StreamCache["CountryData"] = OpenRead[file, BinaryFormat -> True] I don't have webMathematica, so I can't test it on that.
1
Problem solved by restarting the Mathematica Kernel - it seems like an old version of the file was cached at some point and wasn't being reread. This appears to be a recurring problem, and restarting the kernel is the only way I've found to fix it. I'll leave this open for the moment, in case someone knows a good fix for this/reason why this occurred.
1
Given dataUrl, the output of canv.toDataURL(), this works: ImportString[ StringDrop[dataUrl, StringLength["data:image/png;base64,"]], "Base64"] You can specify {"Base64", "PNG"} instead if you like, ImportString seems to auto-detect the type anyway. Within Mathematica, you can get a test dataUrl value here, by clicking "Show in textarea" and ...
Only top voted, non community-wiki answers of a minimum length are eligible | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.20625701546669006, "perplexity": 2438.4331044218393}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-15/segments/1397609538110.1/warc/CC-MAIN-20140416005218-00352-ip-10-147-4-33.ec2.internal.warc.gz"} |
https://scholars.hkbu.edu.hk/en/publications/on-the-laplacian-signless-laplacian-and-normalized-laplacian-char | # On the Laplacian, signless Laplacian and normalized Laplacian characteristic polynomials of a graph
Ji Ming Guo*, Jianxi Li, Wai Chee Shiu
*Corresponding author for this work
Research output: Contribution to journalArticlepeer-review
19 Citations (Scopus)
## Abstract
The Laplacian, signless Laplacian and normalized Laplacian characteristic polynomials of a graph are the characteristic polynomials of its Laplacian matrix, signless Laplacian matrix and normalized Laplacian matrix, respectively. In this paper, we mainly derive six reduction procedures on the Laplacian, signless Laplacian and normalized Laplacian characteristic polynomials of a graph which can be used to construct larger Laplacian, signless Laplacian and normalized Laplacian cospectral graphs, respectively.
Original language English 701-720 20 Czechoslovak Mathematical Journal 63 3 https://doi.org/10.1007/s10587-013-0048-7 Published - Sept 2013
## Scopus Subject Areas
• Mathematics(all)
## User-Defined Keywords
• characteristic polynomial
• Laplacian matrix
• normalized Laplacian matrix
• signless Laplacian matrix
## Fingerprint
Dive into the research topics of 'On the Laplacian, signless Laplacian and normalized Laplacian characteristic polynomials of a graph'. Together they form a unique fingerprint. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8993891477584839, "perplexity": 3682.827552812309}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-14/segments/1679296943695.23/warc/CC-MAIN-20230321095704-20230321125704-00708.warc.gz"} |
https://civil.gateoverflow.in/570/gate2015-1-48 | The $4$-hr unit hydrograph for a catchment is given in the table below. What would be the maximum ordinate of the S – curve (in $m^3/s$) derived from this hydrograph?
$$\begin{array}{|c|c|c|c|c|c|c|c|c|c|c|c|} \hline \\ \text{Time (hr)} & 0 & 2 & 4 & 6 & 8 & 10 & 12 & 14 & 16 & 18 & 20 & 22 & 24 \\ \hline \text{Unit hydrograph} \\ \text{ ordinate} (m^3/s) & 0 & 0.6 & 3.1 & 10 & 13 & 9 & 5 & 2 & 0.7 & 0.3 & 0.2 & 0.1 & 0 \\ \hline \end{array}$$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9644418954849243, "perplexity": 900.3831059229527}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-40/segments/1600401582033.88/warc/CC-MAIN-20200927215009-20200928005009-00363.warc.gz"} |
http://th.nao.ac.jp/MEMBER/tomisaka/Lecture_Notes/StarFormation/3/node82.html | Next: Problem Up: Outflow Previous: Outflow Contents
## Magneto-driven Model
To accelerate gas till supersonic speed, the magnetic force is considered to be an important player. Blandford & Payne (1982) have proposed the magneto-centrifugal wind model'' for the acceleration in two-dimensional axisymmetric configuration.
Figure 4.10 explains the magneto-centrifugal wind mechanism (Fig. 1 of Blandford & Payne 1982). Consider a disk under the gravity of a central star with mass . Assume that gas in the disk at the radius rotates with a Kepler speed of
(4.84)
Consider a gas parcel whose original position was . The effective potential for the particle rotating with an angular rotation speed of is written as
(4.85)
where . (Be careful that ordinary effective potential is calculated for constant angular momentum. However, this is for constant angular rotation speed.) The gas will co-rotate with the same angular rotation speed as the disk, if the magnetic field is sufficiently strong. Equation (4.85) corresponds the effective potential for the gas co-rotating with the disk at . Figure 4.10 plots the isopotential contour lines for the effective potential [eq.(4.85)]. The contour line passing the point represents . The angle between the isopotential line of and the -axis is equal to (see problem below). Further, it can be obtained that the effective potential increases upwardly while it decreases with reaching the central star or radially outwardly.
This leads to an important conclusion that
1. If the angle between the magnetic field line and the -axis is larger than ( ), gas parcel moving along the field line must climb the effective potential. It needs extra energy to depart from the disk.
2. If , gas parcel moving along the field line slides down the effective potential. It can depart from the disk without extra energy.
Be careful that this is valid if the magnetic field is sufficiently strong. If the Kepler disk is threaded with the magnetic field lines with a shallow angle, and if the angular momentum is sufficiently transferred along the magnetic field line, in this case, the gas is accelerated by the extra centrifugal force and finally escapes from the potential well of the central star. This mechanism is called the magneto-centrifugal wind'' mechanism.
Subsections
Next: Problem Up: Outflow Previous: Outflow Contents
Kohji Tomisaka 2007-07-08 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9805170297622681, "perplexity": 1188.4305020676761}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-18/segments/1555578528430.9/warc/CC-MAIN-20190419220958-20190420002958-00347.warc.gz"} |
http://blogs.mathworks.com/steve/2009/02/03/mtest-a-unit-test-harness-for-matlab-code/ | # MTEST – A unit test harness for MATLAB code23
Posted by Steve Eddins,
I just posted MTEST on the MATLAB Central File Exchange. MTEST is a unit test harness for testing MATLAB code. The design of MTEST is based on the popular xUnit architecture.
Now, writing test harnesses isn't exactly a central part of my day job, so let me describe how this project originated and evolved.
I first wrote my own test harness back in 2003 or so, when Digital Image Processing Using MATLAB was published. I needed an easy way to write and run tests for all the code in the book. The test harness we use at MathWorks has evolved over many years to support the needs of hundreds of developers and quality engineers, and dozens of products, so it was a little "big" for the needs of the book project. So I hacked together something simple that was just good enough to serve my own needs.
In 2006 I first presented my "Take Control of Your Code" talk at the International Conference on Image Processing. (I have since given versions of this talk at a half-dozen universities.) I described several tools and techniques intended to help "nonprogrammer" engineers and scientists be more productive with their coding. For testing code I suggested using a good test harness that makes writing and running tests as easy as possible. For testing MATLAB code, I recommended checking out the user-written test harnesses on the MATLAB Central File Exchange.
Then R2008a was released about a year ago, with dramatically improved language features for object-oriented programming. At about the same time I read the book Test-Driven Development, by Kent Beck. The book included a case study on using test-driven development to develop a test harness. And we were actively working on the second edition of Digital Image Processing Using MATLAB. Hey, it's a three-fer! A chance to learn the new language features, learn test-driven development techniques, and update the book's tests all at the same time.
Last spring I met Greg Wilson, co-editor of Beautiful Code, when he visited The MathWorks headquarters in Natick, MA. (Greg's articles on "software carpentry" partially inspired my "Take Control of Your Code" presentation.) Greg was interested in the experiences of engineers and scientists who do their programming in MATLAB, and he encouraged me to continue to develop and refine my MATLAB test harness. And he introduced me to Gerard Meszaros, author of xUnit Test Patterns. Both Greg and Gerard offered helpful architectural and design feedback (thanks, guys!), which I slowly worked to incorporate in the summer and fall. (Very slowly! This was a side project, remember.)
Finally last month I got to the point where I was willing to let people look at it and try it out. You can download it from the MATLAB Central File Exchange. Be sure to check out the extensive documentation. I just discovered that the File Exchange automatically made all of my html documentation files available online, without having to download and unpack the .zip file. That's very cool. The starting point for the documentation is the Readme.html file, and you might also want to look at "MTEST Quick Start - How to write and run tests."
I should point out that there are several other unit test harnesses available on the File Exchange. You can find them by searching for "unit test". I haven't looked at them in any detail, so I don't have particular recommendations. But if you don't like what I've done, take a look at the alternatives.
If you try MTEST, please let me know what you think. You can comment either here or on the File Exchange submission page.
Evan replied on : 2 of 23
Hi,
The documentation says that calling ‘mtest’ with no input arguments will only call functions that start with “test” or “Test”, however, this does not seem to be the case.
Inside of TestSuite.m, in fromPwd(), the comments say the same thing, but again, there seems to be no logic to test this functionality.
I just started working with MTEST, so it might be a case of end-user error, but any help is appreciated. So far, it seems like this will be extremely helpful library.
Thank you again,
Evan
Steve replied on : 3 of 23
Evan—I think you’re right. It looks like I broke this when I refactored the beta version to use the composite pattern for test suites. I’ll post a fix soon.
Steve replied on : 4 of 23
Evan—I submitted an update to MTEST yesterday that fixes the problem.
Evan replied on : 5 of 23
Thanks Steve, the update worked perfectly. For my own use, i created two new assert functions for comparing files and directories. Would love to share them with you and have them added to the distribution. -Evan
Steve replied on : 6 of 23
Evan—I’d love to take a look at your assertion functions. You can find my contact information on my File Exchange author page.
Steve replied on : 8 of 23
Rubshtein Andrey replied on : 9 of 23
Dear Steve,
First of all, thank you very much for this post.
However, it seems that ‘mtest’ will not work with older Matlab version, specifically R2007b.
I wonder, is there a possibility of releasing a version compatible with this version?
Or perhaps you have some other useful advice?
Andrey
Steve replied on : 10 of 23
Rubshtein—MTEST makes heavy use of object-oriented language features introduced in R2008a. I have no plans to port MTEST to earlier MATLAB versions. However, there are other MATLAB test frameworks available. Search the File Exchange for “unit test”, or search Google for “matlab unit test”.
Kay-Uwe replied on : 11 of 23
I am using a package structure to organize my MATLAB project and want to include unit-tests. I would like to have a single command to call all test cases inside the complete package hierarchy.
My stucture is something like package1.subpack1.mfile1 and I put test functions in package1.subpack1.test.test_mfile. I perform a search for “+test” directories by compiling a find command and calling system() (that is neither elegant nor portable), cd to the found directories, call TestSuite.fromPwd() to collect all test-cases and collect the test-suites from all directories in an array. At the end I simply call run() of the array members.
This does not work (no test-cases are found by TestSuite.fromPwd()), but does work, if I rename the test directories to something like “_test” (meaning they are no package hierarchy any more). Is this a bug?
Maybe there is a more elegant way to manage unit-tests in a package hierarchy?
Best regards,
Kay-Uwe
Steve replied on : 12 of 23
Kay-Uwe—You can’t CD into a package directory and then call M-files within that directory as if they weren’t part of a package. That’s why TestSuite.fromPwd() doesn’t find any test cases. It tries to call the M-files in the directory, but MATLAB can’t find them because they aren’t on the path, so no test cases are found.
To gather test cases from within a package, you would need to call the test M-files using the fully scoped package name, as in:
suite = package1.subpack1.test.test_mfile;
suite.run()
Maybe we need a TestSuite.fromPackage() method, and we need to teach runtests to accept package names.
Kay-Uwe replied on : 13 of 23
Having TestSuite.fromPackage() would be nice to have, but so far using simple “test” subdirs (no further package level) works fine for me.
Kay-Uwe
Steve replied on : 14 of 23
Kay-Uwe—Thanks for following up. I am planning to make it easier to use test directories in a package. The MATLAB what function can be used to determine information about a package and its contents.
Oren replied on : 15 of 23
Dear Steve,
I am encountering the same package-structure problem. Are you planning to support it any time soon? Perhaps you are and my usage below is wrong. Thank you so much in advance.
Oren
===
I have a package directory “+core/+xunit” with a file:
classdef TestLearnXunit < TestCase
%TESTLEARNXUNIT A learning test of the xUnit testing framework.
% Detailed explanation goes here
properties (GetAccess = protected)
x
end
%=========================== CONSTRUCTORS ============================
methods
function self = TestLearnXunit(name)
%TestLearnXunit Constructor
% TestCaseInDir(name, testDirectory) constructs a test case
% using the specified name.
self = self@TestCase(name);
end
end
%=========================== SETUP METHODS ===========================
methods
function setUp(self)
%setUp Simple test fixture setup.
self.x = 1;
end
function tearDown(self)
%tearDown Simple test fixture tear-down.
self.x = 0;
end
end
%=========================== TESTING METHODS =========================
methods
function testXValue(self)
assertEqual(self.x, 1);
end
end
end
My path contains the parent directory of “+core”. When I “runtests”, it gets confused about the fully qualified test class name:
>> runtests core.xunit.TestLearnXunit
Starting test run with 2 test cases.
F.
FAILED in 0.002 seconds.
===== Test Case Failure =====
Location: c:\oren\core\src\test\+core\+xunit\TestLearnXunit.m
Name: TestLearnXunit
C:\oren\core\matlab_xunit\xunit\TestCase.m at line 75
C:\oren\core\matlab_xunit\xunit\TestSuite.m at line 78
C:\oren\core\matlab_xunit\xunit\runtests.m at line 73
Undefined function or method 'TestLearnXunit' for input arguments of type 'core.xunit.TestLearnXunit'.
Oren replied on : 16 of 23
Quick update: mtest was trying to run the constructor of the class “TestLearnXunit” as a test case. I renamed the class to “LTestXunit” and it works now.
Following up on a package suite, is there a way to call TestSuite.fromPackage() that will scan the package and all its sub-packages for test classes and run them?
Thanks!
Steve replied on : 17 of 23
Oren—I’m interested in expanding MATLAB xUnit to support test suites in packages, but because of my current activities it’s going to be at least a couple of months before I can look at it.
Peter replied on : 18 of 23
Hi, I’m trying to get started using xUnit with MatLab. Having trouble getting it to recognize test files in some cases, but this is something I can work on figuring out. My main question is, would it be possible to post this on GitHub or somewhere like that?
Steve replied on : 19 of 23
Peter—Be sure to check out the doc for info on writing test cases to be automatically recognized.
I have no plans to post this package elsewhere. Is there some particular reason you’d like to see that?
Oyster Engineer replied on : 20 of 23
Steve,
I want to write a test for a function that returns a cell array with mixed numbers & text. Which assert* test would you recommend using in this case?
The best I’ve come up is:
assertEqual(logical(1), isequal(expectedresult, actualresult))
Thanks.
Steve replied on : 21 of 23
OE—Yes, I haven’t written assertion functions for the container types such as cell or struct. I can suggest a slight simplification of what you wrote:
assertTrue(isequal(expectedresult, actualresult))
idimou replied on : 22 of 23
First of all thank you for this great tool.
I have a collection of classifier functions and I’d like to test them all for specific common properties.
Currently I have to write a test suite for each function. The suites essentially only differ in the name of the function under test. The tests in are all identical.
Is there a way to automate this? (i.e. provide the function name as an argument)
Steve replied on : 23 of 23
idimou—Yes, I can imagine a few ways to do this. Here’s one approach:
function test_suite = classifier_functions_test
initTestSuite
function function_list = setup
function_list = {@classifier1, @classifier2, @classifier3};
function testThis(function_list)
for k = 1:numel(function_list)
% Test "This" for each classifier function.
end
function testThat
for k = 1:numel(function_list)
% Test "That" for each classifier function.
end
These postings are the author's and don't necessarily represent the opinions of MathWorks. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3979438841342926, "perplexity": 2016.913303276279}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-42/segments/1414119649133.8/warc/CC-MAIN-20141024030049-00071-ip-10-16-133-185.ec2.internal.warc.gz"} |
https://www.r-bloggers.com/2013/03/simpler-r-help-tooltips/ | Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.
I posted yesterday about R Help tooltips. I have started to use them e.g. on the graph gallery
However, I’m quickly frustrated with having to write the full url, i.e if I want to add a link to the help page for the pacf function in stats, I need to find this link:
<a href="http://help.r-enthusiasts.com/library/stats/html/acf.html">pacf</a>
Note here that the pacf function is documented in the acf.html file.
I then modified the tooltip plugin so that links like these get the tooltip
<a data-rhelp="stats::pacf">pacf</a>
And the plugin finds the correct link, set it to the href attribute, and enable the tooltip
Some examples: pacf, barchart | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.1689293533563614, "perplexity": 3186.91295845471}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323585204.68/warc/CC-MAIN-20211018155442-20211018185442-00257.warc.gz"} |
http://mathhelpforum.com/latex-help/31035-aligning-equations-spacing-inparaenum.html | ## aligning equations and spacing with inparaenum
I need some help with two questions:
1) aligning equations. I know the basic of the align and eqnarray environments, but I need to fine tune a bit.
2) spacing between inparaenum items
I am writing the solution set for some math problems, and each problem is numbered, and then has subsections with letters, so I am using nested enumerates. Like this:
8. (a) ....
Generally I have the solution start immediately after the letter. In some situations I have several lines of equations that i would like to align around the equal sign. I tried using both the align and eqnarray environments, but they both had the same problem ... they centered the equations on the page and skipped the first line.
I would like the first like to appear right after the letter:
8. (a) cos x = ....
and have the equations under it align with that equal sign (the first equation can be moved to the right a little if necessary for alignment purposes, but not centered).
How do I do this?
The second question is that when I have a bunch of short answers for a problem, I would like them to be listed in line instead vertically.
I found inparaenum that does this, but it puts too little space between the elements in the list. I had to add the space manually. Is there a way to set the default spacing used?
For example, by default I get something like this:
2. (a) cos 45 (b) sin 30 (c) tan 90
and I want something more like this:
2. (a) cos 45 (b) sin 30 (c) tan 90
Thanks for any help I can get. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9282625317573547, "perplexity": 690.1883692888946}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-32/segments/1438042990900.28/warc/CC-MAIN-20150728002310-00160-ip-10-236-191-2.ec2.internal.warc.gz"} |
http://jdh.hamkins.org/the-lattice-of-sets-of-natural-numbers-is-rich/?replytocom=11194 | # The lattice of sets of natural numbers is rich
$\newcommand\of{\subseteq}\newcommand\N{\mathbb{N}}\newcommand\R{\mathbb{R}}\def\<#1>{\left\langle#1\right\rangle}\newcommand\Z{\mathbb{Z}}\newcommand\Q{\mathbb{Q}}\newcommand\ltomega{{{<}\omega}}\newcommand\unaryminus{-}\newcommand\intersect{\cap}\newcommand\union{\cup}\renewcommand\emptyset{\varnothing}$Let us explore the vast and densely populated expanses of the lattice of all sets of natural numbers—the power set lattice $\<P(\N),\of>$.
We find in this lattice every possible set of natural numbers $A\of\N$, and we consider them with respect to the subset relation $A\of B$. This is a lattice order because the union of two sets $A\union B$ is their least upper bound with respect to inclusion and the intersection $A\intersect B$ is their greatest lower bound. Indeed, it is a distributive lattice in light of $A\intersect(B\union C)=(A\intersect B)\union(A\intersect C)$, but furthermore, as a power set algebra it is a Boolean algebra and every Boolean algebra is a distributive lattice.
The empty set $\emptyset$ is the global least element at the bottom of the lattice, of course, and the whole set $\N$ is the greatest element, at the top. The singletons $\set{n}$ are atoms, one step up from $\emptyset$, while their complements $\N\setminus\set{n}$ are coatoms, one step down from $\N$. One generally conceives of the finite sets as clustering near the Earthly bottom of the lattice, finitely close to $\emptyset$, whereas the cofinite sets soar above, finitely close to the heavenly top. In the vast central regions between, in contrast, we find the infinite-coinfinite sets, including many deeply interesting sets such as the prime numbers, the squares, the square-free numbers, the composites, and uncountably many more.
Question. Which familiar orders can we find as suborders in the power set lattice $P(\N)$ of all sets of natural numbers?
We can easily find a copy of the natural-number order $\<\N,\leq>$ in the power set lattice $P(\N)$, simply by considering the chain of initial segments:
$$\emptyset\of\set{0}\of\set{0,1}\of\set{0,1,2}\of\cdots$$
This sequence climbs like a ladder up the left side of the main figure. Curious readers will notice that although every one of these sets is finite and hence conceived as clinging to Earth, as we had said, nevertheless there is no upper bound for this sequence in the lattice other than the global maximum $\N$—any particular natural number is eventually subsumed. Thus one climbs to the heavens on this ladder, which stretches to the very top of the lattice, while remaining close to Earth all the while on every rung.
The complements of those sets similarly form a infinite descending sequence:
$$\cdots\ \of\ \N\setminus\set{0,1,2}\ \of\ \N\setminus\set{0,1}\ \of\ \N\setminus\set{0}\ \of\ \N$$
This chain of cofinite sets dangles like a knotted rope from the heavens down the right side of the main figure. Every knot on this rope is a cofinite set, which we conceived as very near the top, and yet the rope dangles temptingly down to Earth, for there is no lower bound except $\emptyset$.
Can we find a copy of the discrete integer order $\<\Z,\leq>$ in the power set lattice?
Yes, we can. An example is already visible in the red chain at the right side of main lattice diagram, a sky crane hanging in space. Standing at the set of odd numbers, we can ascend in discrete steps by adding additional even numbers one at a time; or we can descend similarly by removing successive odd numbers. The result is a discrete chain isomorphic to the integer order $\Z$, and it is unbounded except by the extreme points $\emptyset$ and $\N$.
Can we find a dense order, say, a copy of the rational line $\<\Q,\leq>$?
What? You want to find a dense order in the lattice of sets of natural numbers? That might seem impossible, if one thinks of the lattice as having a fundamentally discrete nature. The nearest neighbors of any set, after all, are obtained by adding or removing exactly one element—doing so makes a discrete step up or down with no strictly intermediate set. Does the essentially discrete nature of the lattice suggest that we cannot embed the dense order $\<\Q,\leq>$?
No! The surprising fact is that indeed we can embed the rational line into the power set lattice $P(\N)$. Indeed, much more is true—it turns out that we can embed a copy of any countable order whatsoever into the lattice $P(\N)$. Every countable order that occurs anywhere at all occurs in the lattice of sets of natural numbers.
Theorem. The power set lattice on the natural numbers $P(\N)$ is universal for all countable orders. That is, every order relation on a countable domain is isomorphic to a suborder of $\<P(\N),\of>$.
Proof. Let us prove first that every order relation $\<L,\preccurlyeq>$ is isomorphic to the subset relation $\of$ on a collection of sets. Namely, for each $q\in L$ let $q{\downarrow}$ be the down set of $q$, the set of predecessors of $q$:
$$q{\downarrow}=\set{p\in L\mid p\preccurlyeq q}\of L$$
This is a subset of $L$, and what I claim is that
$$p\preccurlyeq q\quad\text{ if and only if }\quad p{\downarrow}\of q{\downarrow}.$$
This is almost immediate. For the forward implication, if $p\preccurlyeq q$, then any order element below $p$ is also below $q$, and so $p{\downarrow}\of q{\downarrow}$. Conversely, if $p{\downarrow}\of q{\downarrow}$, then since $p\in p{\downarrow}$, we must have $p\in q{\downarrow}$ and hence $p\preccurlyeq q$ as desired. So the map $p\mapsto p{\downarrow}$ is an isomorphism of the original order $\<L,\preccurlyeq>$ with the family of all downsets $\set{p{\downarrow}\mid p\in L}$ using the subset relation.
To complete the proof, we simply observe that the power set lattice $P(L)$ of a countably infinite set $L$ is isomorphic to $P(\N)$, and for finite $L$ it is isomorphic to the power set lattice below a finite set of natural numbers. This is because any bijection of $L$ with a set of natural numbers induces a corresponding isomorphism of the respective subsets. So we may find a copy of $L$ inside $P(\N)$, as desired. $\Box$
One may make the proof more concrete by combining the two steps, like this: if $\<L,\preccurlyeq>$ is any countable order relation, then enumerate the domain set $L=\set{p_0,p_1,p_2,\ldots}$, and for each $p\in L$ let $A_p=\set{n\in\N\mid p_n\preccurlyeq p}\of\N$. This is like the down set of $p$, except we take the indices of the elements instead of the elements themselves. It follows that $p\preccurlyeq q$ if and only if $A_p\of A_q$, and so the mapping $p\mapsto A_p$ is an order isomorphism of $\<L,\preccurlyeq>$ with the collection of $A_p$ sets under $\of$, as desired.
Since the set of rational numbers $\Q$ is countable, it follows as an instance of the universality theorem above that we may find a copy of the rational line $\<\Q,\leq>$ inside the power set lattice $\<P(\N),\of>$. Can you find an elegant explicit presentation of rational line in the powerset lattice? In light of the characterization of $\Q$ as a countable endless dense linear order, it will suffice to find any chain in $P(\N)$ that forms a countable endless dense linear order.
But wait, there is more! We can actually find a copy of the real line $\<\R,\leq>$ in the power set lattice on the naturals! Wait…really? How is that possible? The reals are uncountable, and so this would be an uncountable chain the lattice of sets of natural numbers, but every subset $A\of\N$ is countable, and there are only countably many elements to add to $A$ as you go up. How could there be an uncountable chain in the lattice?
Let me explain.
Theorem. The power set lattice on the natural numbers $\<P(\N),\of>$ has an uncountable chain, and indeed, it has a copy of the real continuum $\<\R,\leq>$.
Proof. We have already observed that there must be a copy of the rational line $\<\Q,\leq>$ in the power set lattice $P(\N)$. In other words, there is a map $q\mapsto A_q\of\N$ such that
$$p<q\quad\text{ if and only if }\quad A_p\of A_q$$
for any rational numbers $p,q\in\Q$.
We may now find our desired copy of the real continuum simply by completing this embedding. Namely, for any real number $r\in\R$, let
$$A_r=\bigcup_{\substack{q\leq r\\ q\in\Q}} A_q.$$
Since the sets $A_q$ for rational numbers $q$ form a chain, it follows easily that $r\leq s$ implies $A_r\of A_s$. And if $r<s$, then $A_r$ will be strictly contained in some $A_q$ for a rational number $q$ strictly between $r<q<s$, and consequently strictly contained in $A_s$. From this, it follows that $r\leq s$ if and only if $A_r\of A_s$, and so we have found a copy of the real number order in the power set lattice, as desired. $\Box$
Let us now round out the surprising events of this section by proving another shocking fact—we can also find an uncountable antichain in the power set lattice $P(\N)$.
Theorem. The power set lattice on the natural numbers $\<P(\N),\of>$ has an uncountable antichain, a collection of continuum many pairwise incomparable sets.
Proof. Consider the tree of finite binary sequences $2^{\ltomega}$. This is the set of all finite binary sequences, ordered by the relation $s\leq t$ that holds when $t$ extends $s$ by possibly adding additional binary digits on the end. This is a countable order relation, and so by universality theorem above we may find a copy of it in the power set lattice $P(\N)$. But let us be a little more specific. We shall label each node $s$ of the tree $2^{\ltomega}$ with a distinct natural number. For any infinite binary path $x\in 2^\omega$ through the tree, let $A_x$ be the set of numbers that appear along the path. Every $A_x$ is infinite, but if $x\neq y$, then $x$ and $y$ will eventually branch away from each other, and consequently $A_x$ and $A_y$ will have only finitely many numbers in common. In particular, neither $A_x$ nor $A_y$ will be a subset of the other, and so we have found an antichain in the powerset lattice. The number of paths through the binary tree is the number of infinite binary sequences, which is the same as the cardinality of the continuum of real numbers, as desired. $\Box$
So the lattice $P(\N)$ offers a rich complexity. But is there also homogeneity to be found here? Place yourself at one of the sets in the central region of the lattice, an infinite coinfinite set. There are various new elements for you to add to make a larger set—you can add just this element, or just that one, or any of infinitely many new atoms for you to add to make a larger set. And you could add any combination of those atoms. Above any coinfinite point in the lattice, therefore, one finds a perfect copy of the whole lattice again. Looking upward from any coinfinite set, it always looks the same.
Theorem. The lattice of all sets of natural numbers is homogenous in several respects.
1. The lattice of sets above any given coinfinite set $A\of\N$ is isomorphic to the whole power set lattice $P(\N)$.
2. The lattice of sets below any given infinite set $B\of\N$ is isomorphic to the whole power set lattice $P(\N)$.
3. For any two infinite coinfinite sets $A,B\of \N$, there is an automorphism of the lattice $P(\N)$ carrying $A$ to $B$.
Proof. Let us prove statement (2) first. Consider any infinite set $B\of\N$ and the sublattice in $P(\N)$ below it, which is precisely the power set lattice $P(B)$ of all subsets of $B$. Since $B$ is an infinite set of natural numbers, there is a bijection $\pi:B\to\N$. We may therefore transform subsets of $B$ to subsets of $\N$ by applying the bijection. Namely, for any $X\of B$ define $\bar\pi(X)=\pi[B]=\set{\pi(b)\mid b\in X}$. Since $\pi$ is injective, we have $X\of Y$ if and only if $\bar\pi(X)\of\bar\pi(Y)$, and the map $\bar\pi$ maps onto $P(\N)$ precisely because $\pi$ is surjective, so every $Z\of\N$ is $Z=\bar\pi(X)$, where $X=\pi^{\unaryminus 1}Z=\set{b\in B\mid \pi(b)\in Z}$. So $\bar\pi$ is an isomorphism of the lattice $P(B)$ with $P(\N)$, as desired.
For statement (1), consider any cofinite set $A\of\N$ and let $A{\uparrow}$ be the part of the power set lattice above $A$, meaning $A\uparrow=\set{X\of\N\mid A\of X}$. Since the complement $B=\N\setminus A$ is infinite, there is a bijection of it with the whole set of natural numbers $\pi:B\to\N$. I claim that the lattice $A{\uparrow}$ is isomorphic with the lattice $P(B)$, which by statement (1) we know is isomorphic to $P(\N)$. To see this, we simply cast $A$ out of any set $X$ containing $A$. What remains is a subset of $B$, and every subset of $B$ will be realized. More specifically, if $A\of X$ we define $\tau(X)=X\setminus A=X\intersect B$, and observe that $X\of Y$ if and only if $\tau(X)\of\tau(Y)$, for the sets already containing $A$. And if $Z\of B$, then $Z=\tau(A\union Z)$. So $\tau$ is an isomorphism of the lattice $A{\uparrow}$ with $P(B)$, which by statement (1) is isomorphic to the whole lattice $P(\N)$, as desired.
Finally, let us fix two infinite coinfinite sets $A,B\of \N$. In particular, $A$ and $B$ are in bijection, as are the complements $\N\setminus A$ and $\N\setminus B$. By combining these two bijections, we get a bijection $\pi:\N\to\N$ of $\N$ with itself that carries $A$ exactly to $B$, that is, for which $\pi[A]=B$. (The reader will have an exercise in my book to give a careful account of this construction.) Because $\pi$ is a bijection of $\N$ with itself, it induces a corresponding automorphism of the lattice, defined by $\bar\pi(X)=\pi[X]$ for $X\of\N$. This is an isomorphism of $P(\N)$ with itself, and $\bar\pi(A)=\pi[A]=B$, as desired. $\Box$
Statement (3) of the theorem shows that any two infinite coinfinite sets, being automorphic images of one another, play the same structural role in the lattice $P(\N)$—they will have all the same lattice-theoretic properties. In light of this theorem, therefore, one should not look for structure theorems concerning particular sets in the lattice. Rather, the structure theory of $P(\N)$ is about the structure as a whole, as with the theorems I have proved above.
This is a selection from my book in progress Topics in Logic. It appears in chapter 3, which is on relational logic, and which includes a section on orders with a subsection specifically on the lattice of all sets of natural numbers, because I find it fascinating.
## 2 thoughts on “The lattice of sets of natural numbers is rich”
1. Thanks for the beautiful post, professor — looking forward to the book.
Nitpick: is there a typo in this sentence?
“One generally conceives of the finite sets as clustering near the Earthly bottom of the lattice, finitely close to $\emptyset$, whereas the coinfinite sets soar above, finitely close to the heavenly top”
I believe “coinfinite” should be “cofinite” here.
• Yes, thank you! I have now edited. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9614002704620361, "perplexity": 155.24579532277835}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323585522.78/warc/CC-MAIN-20211022212051-20211023002051-00425.warc.gz"} |
http://advancedintegrals.com/2017/01/relation-between-harmonic-numbers-and-stirling-numbers-of-the-first-kind/ | # Relation between harmonic numbers and Stirling numbers of the first kind
Prove that
$$\left[n\atop 2\right] = H_{n-1}\Gamma(n)$$
By induction on $n$ we have
for $n=2$
$$\left[2\atop 2\right] = H_{1}\times\Gamma(1) = 1$$
Assume that
$$\left[k\atop 2\right] = H_{k-1}\Gamma(k)$$
Then by the recurrence relation
$$\left[k+1\atop 2\right] = k\left[k\atop 2\right] + \left[k\atop 1\right]$$
Use the inductive step
$$\left[k+1\atop 2\right] = \Gamma(k+1)H_{k-1} + \Gamma(k) = \Gamma(k+1)\left\{H_k+\frac{1}{k} \right\} = \Gamma(k+1)H_k$$
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[1] M. Escobedo and J. J. L. Velázquez. Local well posedness for a linear coagulation equation. Trans. Amer. Math. Soc. 365 (2013) 1743-1808. Abstract, references, and article information View Article: PDF [2] Sylvie Monniaux and Jan Prüss. A theorem of the Dore-Venni type for noncommuting operators. Trans. Amer. Math. Soc. 349 (1997) 4787-4814. MR 1433125. Abstract, references, and article information View Article: PDF This article is available free of charge [3] Raymond Roccaforte. Asymptotic expansions of traces for certain convolution operators . Trans. Amer. Math. Soc. 285 (1984) 581-602. MR 752492. Abstract, references, and article information View Article: PDF This article is available free of charge [4] Maria Luisa Mascarenhas. A linear homogenization problem with time dependent coefficient . Trans. Amer. Math. Soc. 281 (1984) 179-195. MR 719664. Abstract, references, and article information View Article: PDF This article is available free of charge [5] Olof J. Staffans. On asymptotically almost periodic solutions of a convolution equation . Trans. Amer. Math. Soc. 266 (1981) 603-616. MR 617554. Abstract, references, and article information View Article: PDF This article is available free of charge [6] Jon C. Helton. Existence of integrals and the solution of integral equations . Trans. Amer. Math. Soc. 229 (1977) 307-327. MR 0445245. Abstract, references, and article information View Article: PDF [7] William T. Reid. Expansion problems associated with a system of integral equations . Trans. Amer. Math. Soc. 33 (1931) 475-485. MR 1501601. Abstract, references, and article information View Article: PDF [8] J. D. Tamarkin and Rudolph E. Langer. On integral equations with discontinuous kernels . Trans. Amer. Math. Soc. 30 (1928) 453-471. MR 1501439. Abstract, references, and article information View Article: PDF [9] Rudolph E. Langer and Eleanor P. Brown. On a class of integral equations with discontinuous kernels . Trans. Amer. Math. Soc. 29 (1927) 683-715. MR 1501410. Abstract, references, and article information View Article: PDF [10] Lawrence M. Graves. Implicit functions and differential equations in general analysis . Trans. Amer. Math. Soc. 29 (1927) 514-552. MR 1501403. Abstract, references, and article information View Article: PDF [11] J. D. Tamarkin. On Laplace's integral equations . Trans. Amer. Math. Soc. 28 (1926) 417-425. MR 1501354. Abstract, references, and article information View Article: PDF [12] Rudolph E. Langer. On the theory of integral equations with discontinuous kernels . Trans. Amer. Math. Soc. 28 (1926) 585-639. MR 1501367. Abstract, references, and article information View Article: PDF [13] Anna J. Pell. Linear equations with two parameters . Trans. Amer. Math. Soc. 23 (1922) 198-211. MR 1501198. Abstract, references, and article information View Article: PDF [14] A. J. Pell. Linear equations with unsymmetric systems of coefficients . Trans. Amer. Math. Soc. 20 (1919) 23-39. MR 1501113. Abstract, references, and article information View Article: PDF [15] A. J. Pell. A general system of linear equations . Trans. Amer. Math. Soc. 20 (1919) 343-355. MR 1501132. Abstract, references, and article information View Article: PDF [16] T. H. Hildebrandt. Errata: On a theory of linear differential equations in general analysis'' [Trans.\ Amer.\ Math.\ Soc. {\bf 18} (1917), no. 1, 73--96; 1501063] . Trans. Amer. Math. Soc. 18 (1917) 540. MR 1501084. Abstract, references, and article information View Article: PDF [17] T. H. Hildebrandt. On a theory of linear differential equations in general analysis . Trans. Amer. Math. Soc. 18 (1917) 73-96. MR 1501063. Abstract, references, and article information View Article: PDF [18] Wallie Abraham Hurwitz. Mixed linear integral equations of the first order . Trans. Amer. Math. Soc. 16 (1915) 121-133. MR 1501004. Abstract, references, and article information View Article: PDF [19] Wallie Abraham Hurwitz. On the pseudo-resolvent to the kernel of an integral equation . Trans. Amer. Math. Soc. 13 (1912) 405-418. MR 1500925. Abstract, references, and article information View Article: PDF [20] Anna Johnson Pell. Applications of biorthogonal systems of functions to the theory of integral equations . Trans. Amer. Math. Soc. 12 (1911) 165-180. MR 1500885. Abstract, references, and article information View Article: PDF
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[–] 0 points1 point (4 children)
Shouldn't theta be [a,b] -> R? And if you have a unit vector, clearly you can define a theta, so there exists a function. Unclear what you are asking.
[–][S] 0 points1 point (3 children)
Yes, theta should be going into R. There is a proposition in my Differential Geometry textbook that proves that such a theta exists by showing that for any continuous T: [a,b] -> S1 there exists theta: [a,b] -> S1 such that our condition relating T and theta holds. The proof they give is pretty hard to understand (to me) so I was wondering if there is an easier method of proof.
The proof the book gives uses uniform continuity of T on [a,b] and partitioning the interval and measuring the angle between the tangent vector at those points of the partition and summing.
[–] 0 points1 point * (0 children)
Absolutely nothing of that was in the question you asked. You asked if there is a function and yes there is a function.
If you want to ask something stronger, you need to specify precisely what other properties you want to show that function has or can have.
And also, in the premise, what are you starting with? A function T that takes on unit vector values, or does it come from something else? Are you assuming it's continuous? Differentiable? Etc.
Edit:
For example, when you asked before you wanted a theta, the second time you wanted a function to S1 , and cos and sin don't take elements of S1 as parameters, so what's the relation you are looking for?
In summary, still unclear what you are asking.
[–] 0 points1 point (0 children)
I assume you want, but aren't saying, that theta be continuous. So if you define exp(t) = (cos(t), sin(t)), you want to say if T: [a,b] -> S1 is continuous, then there exists continuous theta: [a,b] -> R such that T(t) = exp(theta(t)). Uniform continuity isn't actually needed for this result; you can replace [a,b] by any simply connected domain.
The idea of the proof is something like this: let U = S1 - {(1,0)} and V = S1 - {(-1, 0)}. These cover S1 . Now consider T-1 (U) and T-1 (V), which cover the domain of T. On T-1 (U), you can define a theta as desired. (Because on U you can choose branches of inverse trig functions to define a continuous exp-1 . This might be easier if you cover S1 with more, smaller sets.) However, you probably don't want to do this right away. Because T-1 (U) is in general disconnected, there won't be a canonical theta; you will have many choices to make. Instead, if U_0 is a connected subset of T-1 (U), x_0 is a point in U_0, and theta_0 is a real number such that exp(theta_0) = T(x_0), then there is a unique continuous theta: U_0 -> R such that T(x) = exp(theta(x)) and theta(x_0) = theta_0. What this means is that on connected sets, the value of theta is forced by its value at any one point. (This is the best uniqueness result you could hope for; you can always add a multiple of 2pi.) The proof starts to get a little technical. The image of theta lies in exp-1 (T(U_0)). This will be a disjoint union of connected sets each of which is mapped homeomorphically by exp to T(U_0). So the image of theta lies in one connected component. Which one will be determined by theta_0. Because exp is a homeomorphism on this component, we can define theta(x) = exp-1 (T(x)) (where exp-1 is given the correct restricted domain and the correct connected component for its codomain), and uniqueness follows. Of course, all the same arguments apply to V. So now, you pick a point x_0 and an angle theta_0 for that point. By the above argument, you get theta on the connected component of T-1 (U) containing x_0. Then, look at how this component overlaps T-1 (V). Pick a point in intersection and you can get a new theta' on a whole connected component of T-1 (V) which agrees with theta at some point. By uniqueness, theta and theta' agree on the intersection of their domains (since the intersection is connected, if your domain is not a subset of R, you will have to be more clever here), so you can use the gluing lemma to stick them together into a single continuous function. Now you can flip back and forth between U and V extending on connected components until you cover the entire domain of T.
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If what you want is what eruonna proved, you can strip the proof back down to the basics and do it without so much machinery.
Sketch: Use basic trig stuff to show for any x in [a,b] you have a neighborhood of x with a family of valid theta's differing by multiples of 2pi. Then take S={x in [a,b] : exists a valid theta on [a,x] }. Since a in S and b bounds S, you have sup(S)=L exists. Show L=b, since otherwise take the neighborhood of L from the first part, take a point L-epsilon<L in that neighborhood (and L-epsilon in S), and extend a theta on [0,L-epsilon] to a valid theta' on [0,L+epsilon], contradicting L=sup(S). Same argument says L=sup(S) implies L in S. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8583305478096008, "perplexity": 722.9573618068289}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-40/segments/1474738662251.92/warc/CC-MAIN-20160924173742-00081-ip-10-143-35-109.ec2.internal.warc.gz"} |
https://www.visitscanno.com/3bnlpg/6adfaf-connected-planar-graph | Degree of a bounded region r = deg(r) = Number of edges enclosing the regions r. Degree of an unbounded region r = deg(r) = Number of edges enclosing the regions r. In planar graphs, the following properties hold good −, 1. A 1-planar graph is a graph that may be drawn in the plane with at most one simple crossing per edge, and a k-planar graph is a graph that may be drawn with at most k simple crossings per edge. Although a plane graph has an external or unbounded face, none of the faces of a planar map have a particular status. More generally, Euler's formula applies to any polyhedron whose faces are simple polygons that form a surface topologically equivalent to a sphere, regardless of its convexity. n Is their JavaScript “not in” operator for checking object properties. {\displaystyle (E_{\max }=3N-6)} Let Gbe a graph … connected planar graph. In this terminology, planar graphs have graph genus 0, since the plane (and the sphere) are surfaces of genus 0. Circuit A trail beginning and ending at the same vertex. A completely sparse planar graph has Not every planar directed acyclic graph is upward planar, and it is NP-complete to test whether a given graph is upward planar. Moreover, we present a polynomial time approximation scheme for both the connected and unconnected version. Thus, it ranges from 0 for trees to 1 for maximal planar graphs.[12]. planar graph. Strangulated graphs are the graphs in which every peripheral cycle is a triangle. γ 2 For a simple, connected, planar graph with v vertices and e edges and f faces, the following simple conditions hold for v ≥ 3: In this sense, planar graphs are sparse graphs, in that they have only O(v) edges, asymptotically smaller than the maximum O(v2). ! If a maximal planar graph has v vertices with v > 2, then it has precisely 3v − 6 edges and 2v − 4 faces. . 27.22687 The Four Color Theorem states that every planar graph is 4-colorable (i.e. {\displaystyle v-e+f=2} If one places each vertex of the graph at the center of the corresponding circle in a coin graph representation, then the line segments between centers of kissing circles do not cross any of the other edges. = G is a connected bipartite planar simple graph with e edges and v vertices. If n, m, and f denote the number of vertices, edges, and faces respectively of a connected planar graph, then we get n-m+f= 2. In the language of this theorem, All faces (including the outer one) are then bounded by three edges, explaining the alternative term plane triangulation. n [9], The number of unlabeled (non-isomorphic) planar graphs on × In 1879, Alfred Kempe gave a proof that was widely known, but was incorrect, though it was not until 1890 that this was noticed by Percy Heawood, who modified the proof to show that five colors suffice to color any planar graph. In a planar graph with 'n' vertices, sum of degrees of all the vertices is, 2. 4-partite). 213 (2016), 60-70. So graphs which can be embedded in multiple ways only appear once in the lists. We study the problem of finding a minimum tree spanning the faces of a given planar graph. And G contains no simple circuits of length 4 or less. and The method is … 0.43 According to Euler's Formulae on planar graphs, If a graph 'G' is a connected planar, then, If a planar graph with 'K' components then. {\displaystyle D={\frac {E-N+1}{2N-5}}} A connected planar graph having 6 vertices, 7 edges contains _____ regions. Connected planar graphs with more than one edge obey the inequality 10 ( The alternative names "triangular graph"[3] or "triangulated graph"[4] have also been used, but are ambiguous, as they more commonly refer to the line graph of a complete graph and to the chordal graphs respectively. = Every graph that can be drawn on a plane can be drawn on the sphere as well, and vice versa, by means of stereographic projection. I. S. Filotti, Jack N. Mayer. − In general, if the property holds for all planar graphs of f faces, any change to the graph that creates an additional face while keeping the graph planar would keep v − e + f an invariant. Word-representability of face subdivisions of triangular grid graphs, Graphs and Combin. When a connected graph can be drawn without any edges crossing, it is called planar. In other words, it can be drawn in such a way that no edges cross each other. v - e + f = 2. − that for finite planar graphs the average degree is strictly less than 6. 5 - e + 3 = 2. The equivalence class of topologically equivalent drawings on the sphere is called a planar map. [11], The meshedness coefficient of a planar graph normalizes its number of bounded faces (the same as the circuit rank of the graph, by Mac Lane's planarity criterion) by dividing it by 2n − 5, the maximum possible number of bounded faces in a planar graph with n vertices. Complete Graph . 32(5) (2016), 1749-1761. The strangulated graphs include also the chordal graphs, and are exactly the graphs that can be formed by clique-sums (without deleting edges) of complete graphs and maximal planar graphs. Where, |V| is the number of vertices, |E| is the number of edges, and |R| is the number of regions. Create your own flashcards or choose from millions created by other students. If 'G' is a connected planar graph with degree of each region at least 'K' then, 5. Planar graph is graph which can be represented on plane without crossing any other branch. g + Repeat until the remaining graph is a tree; trees have v = e + 1 and f = 1, yielding v − e + f = 2, i. e., the Euler characteristic is 2. We show that a constant factor approximation follows from the unconnected version if the minimum degree is 3. {\displaystyle N} Draw, if possible, two different planar graphs with the same number of vertices, edges, and faces. n 1 6 Euler's formula states that if a finite, connected, planar graph is drawn in the plane without any edge intersections, and v is the number of vertices, e is the number of edges and f is the number of faces (regions bounded by edges, including the outer, infinitely large region), then. Euler's formula can also be proved as follows: if the graph isn't a tree, then remove an edge which completes a cycle. We say that two circles drawn in a plane kiss (or osculate) whenever they intersect in exactly one point. 51 A planar graph may be drawn convexly if and only if it is a subdivision of a 3-vertex-connected planar graph. Not every planar graph corresponds to a convex polyhedron in this way: the trees do not, for example. − A map graph is a graph formed from a set of finitely many simply-connected interior-disjoint regions in the plane by connecting two regions when they share at least one boundary point. "Sur le problème des courbes gauches en topologie", "On the cutting edge: Simplified O(n) planarity by edge addition", Journal of Graph Algorithms and Applications, A New Parallel Algorithm for Planarity Testing, Edge Addition Planarity Algorithm Source Code, version 1.0, Edge Addition Planarity Algorithms, current version, Public Implementation of a Graph Algorithm Library and Editor, Boost Graph Library tools for planar graphs, https://en.wikipedia.org/w/index.php?title=Planar_graph&oldid=995765356, Creative Commons Attribution-ShareAlike License, Theorem 2. When a planar graph is drawn in this way, it divides the plane into regions called faces. {\displaystyle E} More generally, the genus of a graph is the minimum genus of a two-dimensional surface into which the graph may be embedded; planar graphs have genus zero and nonplanar toroidal graphs have genus one. Then: v −e+r = 2. 10.7 #17 G is a connected planar simple graph with e edges and v vertices with v 4. − In analogy to the characterizations of the outerplanar and planar graphs as being the graphs with Colin de Verdière graph invariant at most two or three, the linklessly embeddable graphs are the graphs that have Colin de Verdière invariant at most four. This relationship holds for all connected planar graphs. The graph K3,3, for example, has 6 vertices, 9 edges, and no cycles of length 3. A plane graph can be defined as a planar graph with a mapping from every node to a point on a plane, and from every edge to a plane curve on that plane, such that the extreme points of each curve are the points mapped from its end nodes, and all curves are disjoint except on their extreme points. K In practice, it is difficult to use Kuratowski's criterion to quickly decide whether a given graph is planar. 201 (2016), 164-171. K A Euclidean graph is a graph in which the vertices represent points in the plane, and the edges are assigned lengths equal to the Euclidean distance between those points; see Geometric graph theory. Therefore, by Theorem 2, it cannot be planar. The asymptotic for the number of (labeled) planar graphs on In analogy to Kuratowski's and Wagner's characterizations of the planar graphs as being the graphs that do not contain K5 or K3,3 as a minor, the linklessly embeddable graphs may be characterized as the graphs that do not contain as a minor any of the seven graphs in the Petersen family. However, a three-dimensional analogue of the planar graphs is provided by the linklessly embeddable graphs, graphs that can be embedded into three-dimensional space in such a way that no two cycles are topologically linked with each other. It follows via algebraic transformations of this inequality with Euler's formula Scheinerman's conjecture (now a theorem) states that every planar graph can be represented as an intersection graph of line segments in the plane. A simple non-planar graph with minimum number of vertices is the complete graph K 5. A complete presentation is given of the class g of locally finite, edge-transitive, 3-connected planar graphs. Euler found out the number of regions in a planar graph as a function of the number of vertices and number of edges in the graph. Let F be the set of faces of a planar drawing of G. Then jVjj Ej+ jFj= 2: Proof. An upward planar graph is a directed acyclic graph that can be drawn in the plane with its edges as non-crossing curves that are consistently oriented in an upward direction. , When a planar graph is drawn in this way, it divides the plane into regions called faces. Draw, if possible, two different planar graphs with the same number of vertices, edges, and faces. The prism over a graph G is the Cartesian product of G with the complete graph K 2.A graph G is hamiltonian if there exists a spanning cycle in G, and G is prism-hamiltonian if the prism over G is hamiltonian.. Rosenfeld and Barnette (1973) conjectured that every 3-connected planar graph is prism-hamiltonian. [1][2] Such a drawing is called a plane graph or planar embedding of the graph. Semi-transitive orientations and word-representable graphs, Discr. 7 If there are no cycles of length 3, then, This page was last edited on 22 December 2020, at 19:50. , because each face has at least three face-edge incidences and each edge contributes exactly two incidences. {\displaystyle K_{3,3}} ... An edge in a connected graph whose deletion will no longer cause the graph to be connected. At first sight it looks as non planar graph since two resistor cross each other but it is planar graph which can be drawn as shown below. Sun. A simple connected planar graph is called a polyhedral graph if the degree of each vertex is … Steinitz's theorem says that the polyhedral graphs formed from convex polyhedra are precisely the finite 3-connected simple planar graphs. A graph is planar if it has a planar drawing. Indeed, we have 23 30 + 9 = 2. 6.3.1 Euler’s Formula There is a simple formula relating the numbers of vertices, edges, and faces in a connected plane graph. Suppose G is a connected planar graph, with v nodes, e edges, and f faces, where v ≥ 3. = Discussion: Because G is bipartite it has no circuits of length 3. Plane graphs can be encoded by combinatorial maps. 2 .[10]. 2 In a maximal planar graph (or more generally a polyhedral graph) the peripheral cycles are the faces, so maximal planar graphs are strangulated. Induction: Suppose the formula works for all graphs with no more than nedges. 2 D / f Word-representability of triangulations of grid-covered cylinder graphs, Discr. A polynomial-time algorithm for determining the isomorphism of graphs of fixed genus. E {\displaystyle n} ⋅ If a connected planar graph G has e edges and v vertices, then 3v-e≥6. Every maximal planar graph is a least 3-connected. 3 Show that if G is a connected planar graph with girth^1 k greaterthanorequalto 3, then E lessthanorequalto k (V - 2)/(k - 2). Thomassen [5] further strengthened this result by proving that every 4{connected planar graph is Hamiltonian{connected, that is, has a Hamiltonian path connecting any two prescribed vertices. As a consequence, planar graphs also have treewidth and branch-width O(√n). vertices is Appl. Below figure show an example of graph that is planar in nature since no branch cuts any other branch in graph. Connected planar graphs The table below lists the number of non-isomorphic connected planar graphs. nodes, given by a planar graph A graph is called 1-planar if it can be drawn in the plane such that every edge has at most one crossing. However, there exist fast algorithms for this problem: for a graph with n vertices, it is possible to determine in time O(n) (linear time) whether the graph may be planar or not (see planarity testing). Euler’s Formula: Let G = (V,E) be a connected planar graph, and let v = |V|, e = |E|, and r = number of regions in which some given embedding of G divides the plane. n , alternatively a completely dense planar graph has [5], Outerplanar graphs are graphs with an embedding in the plane such that all vertices belong to the unbounded face of the embedding. A toroidal graph is a graph that can be embedded without crossings on the torus. The numbers of planar connected graphs with, 2,... nodes are 1, 1, 2, 6, 20, 99, 646, 5974, 71885,... (OEIS A003094; Steinbach 1990, p. 131). Planar straight line graphs (PSLGs) in Data Structure, Eulerian and Hamiltonian Graphs in Data Structure. This is no coincidence: every convex polyhedron can be turned into a connected, simple, planar graph by using the Schlegel diagram of the polyhedron, a perspective projection of the polyhedron onto a plane with the center of perspective chosen near the center of one of the polyhedron's faces. Note that isomorphism is considered according to the abstract graphs regardless of their embedding. ⋅ When a connected graph can be drawn without any edges crossing, it is called planar. A plane graph is said to be convex if all of its faces (including the outer face) are convex polygons. We construct a counterexample to the conjecture. and N When at most three regions meet at a point, the result is a planar graph, but when four or more regions meet at a point, the result can be nonplanar. The circle packing theorem, first proved by Paul Koebe in 1936, states that a graph is planar if and only if it is a coin graph. 3. E The density , where N and A theorem similar to Kuratowski's states that a finite graph is outerplanar if and only if it does not contain a subdivision of K4 or of K2,3. "Triangular graph" redirects here. {\displaystyle D=1}. Any graph may be embedded into three-dimensional space without crossings. [8], Almost all planar graphs have an exponential number of automorphisms. The Polish mathematician Kazimierz Kuratowski provided a characterization of planar graphs in terms of forbidden graphs, now known as Kuratowski's theorem: A subdivision of a graph results from inserting vertices into edges (for example, changing an edge •——• to •—•—•) zero or more times. 7.4. non-isomorphic) duals, obtained from different (i.e. A 1-outerplanar embedding of a graph is the same as an outerplanar embedding. In your case: v = 5. f = 3. Such a drawing (with no edge crossings) is called a plane graph. Since 2 equals 2, we can see that the graph on the right is a planar graph as well. We will prove this Five Color Theorem, but first we need some other results. Using these symbols, Euler窶冱 showed that for any connected planar graph, the following relationship holds: v e+f =2. If 'G' is a simple connected planar graph, then, There exists at least one vertex V ∈ G, such that deg(V) ≤ 5, 6. Math. We consider a connected planar graph G with k + 1 edges. Quizlet is the easiest way to study, practice and master what you’re learning. Then prove that e ≤ 3 v − 6. to the number of possible edges in a network with , giving D A planar connected graph is a graph which is both planar and connected. Sun. PLANAR GRAPHS 98 1. {\displaystyle 30.06^{n}} Data Structures and Algorithms Objective type Questions and Answers. 3 of a planar graph, or network, is defined as a ratio of the number of edges Planar graphs generalize to graphs drawable on a surface of a given genus. vertices is between Math. In graph drawing and geometric graph theory, a Tutte embedding or barycentric embedding of a simple 3-vertex-connected planar graph is a crossing-free straight-line embedding with the properties that the outer face is a convex polygon and that each interior vertex is at the average (or barycenter) of its neighbors' positions. 27.2 D Proof: by induction on the number of edges in the graph. Figure 5.30 shows a planar drawing of a graph with $$6$$ vertices and $$9$$ edges. We assume all graphs are simple. {\displaystyle 27.2^{n}} Every planar graph divides the plane into connected areas called regions. Appl. Theorem – “Let be a connected simple planar graph with edges and vertices. ≈ Such a subdivision of the plane is known as a planar map. Word-representable planar graphs include triangle-free planar graphs and, more generally, 3-colourable planar graphs [13], as well as certain face subdivisions of triangular grid graphs [14], and certain triangulations of grid-covered cylinder graphs [15]. As an illustration, in the butterfly graph given above, v = 5, e = 6 and f = 3. non-homeomorphic) embeddings. are the forbidden minors for the class of finite planar graphs. 30.06 For k > 1 a planar embedding is k-outerplanar if removing the vertices on the outer face results in a (k − 1)-outerplanar embedding. A Halin graph is a graph formed from an undirected plane tree (with no degree-two nodes) by connecting its leaves into a cycle, in the order given by the plane embedding of the tree. In a finite, connected, simple, planar graph, any face (except possibly the outer one) is bounded by at least three edges and every edge touches at most two faces; using Euler's formula, one can then show that these graphs are sparse in the sense that if v ≥ 3: Euler's formula is also valid for convex polyhedra. Each region has some degree associated with it given as- Degree of Interior region = Number of edges enclosing that region Degree of Exterior region = Number of edges exposed to that region The planar separator theorem states that every n-vertex planar graph can be partitioned into two subgraphs of size at most 2n/3 by the removal of O(√n) vertices. Line graph § Strongly regular and perfect line graphs, Fraysseix–Rosenstiehl planarity criterion. Note that this implies that all plane embeddings of a given graph define the same number of regions. {\displaystyle K_{5}} e A universal point set is a set of points such that every planar graph with n vertices has such an embedding with all vertices in the point set; there exist universal point sets of quadratic size, formed by taking a rectangular subset of the integer lattice. of all planar graphs which does not refer to the planar embedding, and then showing that K 5 does not satisfy this property. In graph theory, a planar graph is a graph that can be embedded in the plane, i.e., it can be drawn on the plane in such a way that its edges intersect only at their endpoints. If G has no cycles, i.e., G is a tree, then e = v ¡ 1 (every tree with v vertices has v ¡1 edges), f = 1; so v ¡e+f = 2. However, there exist fast algorithms for this problem: for a graph with n vertices, it is possible to determine in time O(n) (linear time) whether the graph may be planar or not (see planarity testing). 0 See "graph embedding" for other related topics. This result provides an easy proof of Fáry's theorem, that every simple planar graph can be embedded in the plane in such a way that its edges are straight line segments that do not cross each other. Planar Graph. Polyhedral graph. The planar representation of the graph splits the plane into connected areas called as Regions of the plane. While the dual constructed for a particular embedding is unique (up to isomorphism), graphs may have different (i.e. Kempe's method of 1879, despite falling short of being a proof, does lead to a good algorithm for four-coloring planar graphs. If 'G' is a simple connected planar graph (with at least 2 edges) and no triangles, then. The term "dual" is justified by the fact that G** = G; here the equality is the equivalence of embeddings on the sphere. ≈ ⋅ This is now the Robertson–Seymour theorem, proved in a long series of papers. A "coin graph" is a graph formed by a set of circles, no two of which have overlapping interiors, by making a vertex for each circle and an edge for each pair of circles that kiss. M. Halldórsson, S. Kitaev and A. Pyatkin. N Like outerplanar graphs, Halin graphs have low treewidth, making many algorithmic problems on them more easily solved than in unrestricted planar graphs.[7]. Instead of considering subdivisions, Wagner's theorem deals with minors: A minor of a graph results from taking a subgraph and repeatedly contracting an edge into a vertex, with each neighbor of the original end-vertices becoming a neighbor of the new vertex. Let G = (V;E) be a connected planar graph. e D When a connected graph can be drawn without any edges crossing, it is called planar. A triangulated simple planar graph is 3-connected and has a unique planar embedding. n = Every outerplanar graph is planar, but the converse is not true: K4 is planar but not outerplanar. If both theorem 1 and 2 fail, other methods may be used. − These theorems provide necessary conditions for planarity that are not sufficient conditions, and therefore can only be used to prove a graph is not planar, not that it is planar. The graph G may or may not have cycles. Suppose it is true for planar graphs with k edges, k ‚ 0. Note − Assume that all the regions have same degree. Properties of Planar Graphs: If a connected planar graph G has e edges and r regions, then r ≤ e. If a connected planar graph G has e edges, v vertices, and r regions, then v-e+r=2. n {\displaystyle 2e\geq 3f} Planar Graph. So we have 1 −0 + 1 = 2 which is clearly right. By induction. g ≥ For two planar graphs with v vertices, it is possible to determine in time O(v) whether they are isomorphic or not (see also graph isomorphism problem). Equivalently, they are the planar 3-trees. A face of a planar drawing of a graph is a region bounded by edges and vertices and not containing any other vertices or edges. (47) In the graph above in Figure 17, v = 23, e = 30, and f = 9, if we remember to count the outside face. Then G* is again the embedding of a (not necessarily simple) planar graph; it has as many edges as G, as many vertices as G has faces and as many faces as G has vertices. Fáry's theorem states that every simple planar graph admits an embedding in the plane such that all edges are straight line segments which don't intersect. If G is the planar graph corresponding to a convex polyhedron, then G* is the planar graph corresponding to the dual polyhedron. max {\displaystyle D} Duals are useful because many properties of the dual graph are related in simple ways to properties of the original graph, enabling results to be proven about graphs by examining their dual graphs. Show that e 2v – 4. Every simple outerplanar graph admits an embedding in the plane such that all vertices lie on a fixed circle and all edges are straight line segments that lie inside the disk and don't intersect, so n-vertex regular polygons are universal for outerplanar graphs. {\displaystyle n} A subset of planar 3-connected graphs are called polyhedral graphs. A graph 'G' is non-planar if and only if 'G' has a subgraph which is homeomorphic to K5 or K3,3. 3 There’s another simple trick to keep in mind. A complete graph K n is a planar if and only if n; 5. The simple non-planar graph with minimum number of edges is K 3, 3. {\displaystyle g\cdot n^{-7/2}\cdot \gamma ^{n}\cdot n!} Every Halin graph is planar. 15 3 1 11. Since the property holds for all graphs with f = 2, by mathematical induction it holds for all cases. γ Theorem 6.3.1 immediately implies that every 3-connected planar graph has a unique plane embedding. Whitney [7] proved that every 4{connected planar triangulation has a Hamiltonian circuit, and Tutte [6] extended this to all 4{connected planar graphs. 5 Proceedings of the 12th Annual ACM Symposium on Theory of Computing, p.236–243. = The above is a direct corollary of the fact that a graph G is outerplanar if the graph formed from G by adding a new vertex, with edges connecting it to all the other vertices, is a planar graph.[6]. Graphs with higher average degree cannot be planar. When a planar graph is drawn in this way, it divides the plane into regions called faces. {\displaystyle D=0} v The Euler formula tells us that all plane drawings of a connected planar graph have the same number of faces namely, 2+m-n. A simple graph is called maximal planar if it is planar but adding any edge (on the given vertex set) would destroy that property. A planar graph is a graph that can be drawn in the plane without any edge crossings. Apollonian networks are the maximal planar graphs formed by repeatedly splitting triangular faces into triples of smaller triangles. Therefore, by Corollary 3, e 2v – 4. {\displaystyle g\approx 0.43\times 10^{-5}} E ) Klaus Wagner asked more generally whether any minor-closed class of graphs is determined by a finite set of "forbidden minors". (b) Use (a) to prove that the Petersen graph is not planar. Draw, if possible, two different planar graphs with the same number of vertices, edges, and faces. According to Sum of Degrees of Regions Theorem, in a planar graph with 'n' regions, Sum of degrees of regions is −, Based on the above theorem, you can draw the following conclusions −, If degree of each region is K, then the sum of degrees of regions is, If the degree of each region is at least K(≥ K), then, If the degree of each region is at most K(≤ K), then. We assume here that the drawing is good, which means that no edges with a … 1 Then the number of regions in the graph … This lowers both e and f by one, leaving v − e + f constant. Equivalently, it is a polyhedral graph in which one face is adjacent to all the others. For line graphs of complete graphs, see. 5 n Other articles where Planar graph is discussed: combinatorics: Planar graphs: A graph G is said to be planar if it can be represented on a plane in such a fashion that the vertices are all distinct points, the edges are simple curves, and no two edges meet one another except at their terminals.… {\displaystyle \gamma \approx 27.22687} A graph is k-outerplanar if it has a k-outerplanar embedding. 5 In practice, it is difficult to use Kuratowski's criterion to quickly decide whether a given graph is planar. An apex graph is a graph that may be made planar by the removal of one vertex, and a k-apex graph is a graph that may be made planar by the removal of at most k vertices. , Eulerian and Hamiltonian graphs in Data Structure, Eulerian and Hamiltonian graphs in which one face is to! Plane graph branch cuts any other branch in graph ], Almost all planar the... 6\ ) vertices and \ ( 9\ ) edges graphs have graph genus 0 ) edges your. Simple graph with minimum number of edges is K 3, e edges and v vertices edges... Show that a constant factor approximation follows from the unconnected version different ( i.e ' K ',! Base: if e= 0, the graph to be convex if all of its faces ( the. Graphs is determined by a finite set of faces of a graph is easiest... Into connected areas called as regions of the 12th Annual ACM Symposium on of... E = 6 and f by one, leaving v − 6 convexly if and if..., since the property holds for all graphs with the same number of automorphisms a simple connected planar graph with! ) and no cycles of length 4 or less approximation scheme for both the and!, 2 degree can not be planar induction: suppose the formula works for all graphs with higher degree! Graph which can be drawn without any edges crossing, it can be embedded into three-dimensional without... Be a connected planar graphs formed from convex polyhedra are precisely the finite 3-connected simple graph! Property holds for all cases illustration, in the plane without any edge crossings ) is called 1-planar it! Graphs is determined by a finite set of faces of a planar graph divides the plane into called. 2V – 4 own flashcards or choose from millions created by other students connected planar graph is homeomorphic to or! Other branch in graph, 9 edges, and no cycles of length 3, e and... Eulerian and Hamiltonian graphs in Data Structure, Eulerian and Hamiltonian graphs in which every peripheral cycle is subdivision! Difficult to use Kuratowski 's criterion to quickly decide whether a given graph is drawn in such a subdivision the! Every edge has at most one crossing all graphs with the same number of edges, explaining the term! The faces of a given planar graph divides the plane into regions called faces a good algorithm four-coloring. Fail, other methods may be used difficult to use Kuratowski 's criterion to quickly decide whether a graph... 1 −0 + 1 edges or choose from millions created by other.... All the others Because G is a graph that is planar if and only if ' '! S another simple trick to keep in mind on Theory of Computing p.236–243. Polyhedra are precisely the finite 3-connected simple planar graph G may or not! S. Kitaev, and |R| is the number of vertices, sum connected planar graph degrees of the! Graph, with v 4 graph that is planar if and only if connected planar graph ; 5 use!. [ 12 ] considered according to the abstract graphs regardless of their embedding and no cycles length... Has 6 vertices, then, 5 edges in the plane without any edge crossings ) is called if. Whose deletion will no longer cause the graph K3,3, for example if the minimum is! To K5 or K3,3 to all the vertices is the planar graph the! Unique planar embedding ' vertices, edges, K ‚ 0 2 edges ) and triangles! External or unbounded face, none of the graph to 1 for maximal planar with. Plane ( and connected planar graph sphere is called a plane graph or planar embedding of a graph that be... Corresponds to a convex polyhedron, then planar simple graph with e edges and v vertices ) vertices and (. Planarity criterion we present a polynomial time approximation scheme for both the connected and unconnected version if the minimum is... May have different ( i.e define the same as an outerplanar embedding ) whenever they in... Jvjj Ej+ jFj= 2: proof to all the regions have same.. Dual polyhedron we present a polynomial time approximation scheme for both the connected and version! A polyhedral graph in which every peripheral cycle is a graph that can be drawn in such a drawing called... Graph has an external or unbounded face, none of the plane such that every edge has at one... = 2 which is homeomorphic to K5 or K3,3 your case: v e+f =2 1 = 2 by! Any other branch in graph a particular status representation of the plane such every. ( 5 ) ( 2016 ), 1749-1761 example, has 6 vertices, then 3v-e≥6 it difficult. Problem of finding a minimum tree spanning the faces of a planar graph with... B. Y n ; 5 isomorphism ), 1749-1761 \cdot \gamma ^ { n } \cdot n }. S another simple trick to keep in mind embeddings of a given is... Simple planar graph is 3-connected and has a planar map have a particular status where, |V| is the graph. Assume that all plane embeddings of a graph which can be drawn in such a drawing is called planar type. It holds for all graphs with f = 2, by Corollary 3, 3 Computing., and faces, 9 edges, and f = 3 perfect line graphs PSLGs... Not in ” operator for checking object properties does lead to a good for... Simple non-planar graph with e edges and vertices a plane graph has a k-outerplanar embedding 1 and fail. Since no branch cuts any other branch no circuits of length 3 ( b ) use ( a ) prove. For maximal planar graphs also have treewidth and branch-width O ( √n ) 5, e –! We present a polynomial time approximation scheme for both the connected and unconnected version 4-colorable ( i.e all.. For planar graphs with the same number of edges is K 3, e edges and v vertices edges. Your case: v e+f =2 and f faces, where v ≥.. The property holds for all cases example of graph that can be embedded without crossings on torus... The unconnected version any connected planar graphs with the same vertex of papers theorem states that every graph! Planar if and only if ' G ' has a unique planar of... Three-Dimensional space without crossings at the same number of edges, K ‚ 0 ( 6\ ) vertices \! A way that no edges cross each other is planar, but first we need some results. Graph may be used 2, we present a polynomial time approximation for... Space without crossings on the number of edges is K 3, 3 edge crossings ) called! And faces good algorithm for determining the isomorphism of graphs of fixed genus another simple trick to keep mind. Fraysseix–Rosenstiehl planarity criterion plane graph is planar but not outerplanar vertices and \ ( 6\ ) and! The formula works for all graphs with the same vertex is 3-connected and a! With K + 1 = 2 which is both planar and connected 5. f = 2 which homeomorphic. Polyhedral graphs formed by repeatedly splitting triangular faces into triples of smaller triangles plane embeddings a... 1 edges a constant factor approximation follows from the unconnected version graph can be drawn any! To quickly decide whether a given planar graph with ' n ',... Can not be planar finite set of forbidden minors '' study, practice master! On the torus the planar graph, the following relationship holds: v e+f.... 9 edges, explaining the alternative term plane triangulation edges is K 3, then adjacent to all the have. Planar map of their embedding called regions sum of degrees of all the regions same... G is a connected graph whose deletion will no longer cause the graph may! With minimum number of edges in the butterfly graph given above, =... Outerplanar embedding is 4-colorable ( i.e this lowers both e and f faces, where v ≥.... By induction on the number of edges is K 3, then, this was! Below figure show an example of graph that can be drawn without any edges crossing connected planar graph. Edges contains _____ regions this page was last edited on 22 December,! Questions and Answers planar but not outerplanar first we need some other results is not planar simple graph... Bipartite planar simple graph with ' n ' vertices, |E| is the easiest way to,! Isomorphism is considered according to the abstract graphs regardless of their embedding, where v ≥ 3 tree. Decide whether a given planar graph corresponds to a good algorithm for four-coloring graphs. Subdivisions of triangular grid graphs, Discr other related topics whose deletion will no longer cause the to! Or K3,3 polyhedra are precisely the finite 3-connected simple planar graph is graph can... K ‚ 0 divides the plane without any edges crossing, it can be drawn convexly if only! graph embedding '' for other related topics 3-connected simple planar graphs generalize to graphs drawable a! Test whether a given planar graph is upward planar, and B. Y minimum spanning. Note − Assume that all plane embeddings of a planar drawing a complete graph n... Following relationship holds: v = 5, e 2v – 4 grid-covered cylinder graphs, Fraysseix–Rosenstiehl planarity criterion,... Upward planar, but first we need some other results connected areas called.. 1 for maximal planar graphs also have treewidth and branch-width O ( √n ), edges. Trees do not, for example, has 6 vertices, 7 edges contains _____ regions: proof graph can! Theorem – “ let be a connected planar graph crossings on the number of edges explaining. With \ ( 6\ ) vertices and \ ( 9\ ) edges with single! | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5433046221733093, "perplexity": 393.858764656738}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178356232.19/warc/CC-MAIN-20210226060147-20210226090147-00521.warc.gz"} |
https://www.physicsforums.com/threads/excitation-to-higher-energy-levels.738115/ | Excitation to higher energy levels
1. Feb 13, 2014
Chemist@
If an electron gets excited from K to L shell, it will actually finish in the 2p subshell and then deexcite to 2s and 1s at the end, right?
2. Feb 13, 2014
It 'can' de-excite from 2p-2s or it 'can' directly de-excite to 1s. Same applies to excitation.
3. Feb 13, 2014
Chemist@
But that doesn't seem to follow the selection rules.
4. Feb 13, 2014
Which rules are you talking about?
5. Feb 13, 2014
Chemist@
6. Feb 14, 2014
Chemist@
Anyone?
7. Feb 14, 2014
Bill_K
Not sure what the question is, if there is one.
Are you maybe asking, "If an atom decays from 2p to 2s, then how does the 2s subsequently decay to 1s, since this violates the rule for allowed transitions?"
From http://www.tapir.caltech.edu/~chirata/ay102/Atomic.pdf: [Broken]
Last edited by a moderator: May 6, 2017
8. Feb 14, 2014
Chemist@
Great. Thanks.
Similar Discussions: Excitation to higher energy levels | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8517502546310425, "perplexity": 6426.179921616985}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-34/segments/1502886102663.36/warc/CC-MAIN-20170816212248-20170816232248-00093.warc.gz"} |
https://okayama.pure.elsevier.com/en/publications/diffusion-behaviour-of-se-ii-and-smiii-in-compacted-sodium-benton | # Diffusion Behaviour of Se(-II) and Sm(III) in Compacted Sodium Bentonite
Research output: Contribution to journalArticlepeer-review
12 Citations (Scopus)
## Abstract
Apparent diffusion coefficients (Da) for Se(-II) and Sm(III) in a compacted sodium bentonite, Kunigel-V1®, were obtained for a range of dry densities from 800-1800 kg · m-3. The Da values for Se were obtained under reducing conditions and those for Sm were obtained over a pH range of 8-11. The Da values for Se were between 6.1 × 10-11 and 4.3 × 10-10 m2 · s-1 and showed a tendency to slightly decrease with increasing dry density of bentonite. The dominant Se species in the porewater is predicted to be HSe-, and the Da values were approximately the same as those for TcO4-, which has the same charge. The Da values obtained for Sm were between 8.0 × 10-15 and 1.0 × 10-13 m2 · s-1 and decreased with increasing dry density of bentonite. The dominant species of Sm in the porewater are predicted to be SmCO3+ and Sm(CO3)2- at pH8 and 11, respectively. However, all Da values for the same bentonite density were approximately the same and no influence of the porewater pH on diffusivity was found. The Da values for Sm were similar to those for Eu, Am and Cm in the same range of bentonite density. Therefore, it is concluded that these trivalent elements show similar diffusion behaviour.
Original language English 173-178 6 Radiochimica Acta 82 1 Published - Dec 1 1998 Yes
## Keywords
• Diffusion
• Reducing conditions
• Samarium
• Selenium
• Sodium bentonite
• pH dependence
## ASJC Scopus subject areas
• Physical and Theoretical Chemistry | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9032333493232727, "perplexity": 7140.876948034034}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178351134.11/warc/CC-MAIN-20210225124124-20210225154124-00417.warc.gz"} |
http://mathoverflow.net/questions/141404/commutativity-in-the-fundamental-group-and-knot-theory | # Commutativity in the Fundamental Group and Knot Theory
Let $M$ be a connected $3$-manifold and let $\alpha$ and $\beta$ be elements in $\pi_1(M)$. Then $\alpha$ and $\beta$ can be represented by two knots $a$ and $b$ in $M$. We may further require that the images of $a$ and $b$ are disjoint. My question is:
Is there any necessary/sufficient condition on the knots $a$ and $b$ (or for the link $a\bigcup b$) for $\alpha$ and $\beta$ to commute in $\pi_1(M)$?
I believe that there are conclusions (what conclusions?) for satellite knots. Any comment or reference will be greatly appreciated.
-
I find strange that you can take them to be disjoint since in order to talk about the fundamental group you have to choose a base point where every path starts and ends. – Fernando Muro Sep 6 '13 at 4:59
You are right. I want to look at the link $a\bigcup b$ and as $a$ and $b$ necessarliy intersect at the base point, we can actually have two ways to create the link $a\bigcup b$ if we shift $b$, say, a little bit from the basepoint so that $a$ and $b$ do not intersect. Or perhaps it is better to simply consider $a\bigcup b$ as a virtual knot? – Zuriel Sep 6 '13 at 5:08
The question still makes no sense to me: Every element of $\pi_1(M,x)$ is represented by infinitely many (isotopy classes of) knots. It is even worse for a pair of knots with the common base-point. Lastly, you have to deal with non-uniqueness of resolution of the crossing of $\alpha$ and $\beta$. I suggest you think more about the question you are trying to ask. – Misha Sep 6 '13 at 7:49
Since every homotopy class of loops is represented by infinitely many knots, the only way I can interpret the question is:
Is there a characterization of commuting pairs of elements $\alpha, \beta$ of $\pi_1(M)$ in terms of existence of some "nice" knots representing these based homotopy classes?
(I am dropping the disjointness condition since it does not make much sense to me.)
Then the answer is: If and only if $\alpha, \beta$ are represented by powers of torus knots in $M$ lying on the same torus which is either embedded in $M$ or is a "vertical" torus immersed in one of the Seifert components of the JSJ decomposition of $M$.
The proof is quite easy and follows from the JSJ theory, once you know what it is. The point is that either the group generated by $\alpha, \beta$ is cyclic (possibly finite) in which case both loops could be simultaneously (based) homotoped to an embedded solid torus in $M$ or it is free abelian of rank 2, in which case you apply the JSJ theory.
-
I believe Misha's comment directly addresses some of the problems with you question as stated. However, let me say a few words about the issues here and then mention some observations that might help you refine your ideas of your question.
Ignoring the issues of base points (which are also important) and instead concerning ourselves with only free homotopy classes of curves still leaves some issues. In the picture below, consider the green curve as $a$. The homotopy class of $a$, $\alpha$ is trivial, and so it commutes with everything in $\pi_1(M)$.
(This picture highlights one distinction between homotopy classes and isotopy classes.)
Also, in this case the underlying manifold is $S^1 \times D^2$ so all elements in the fundamental group commute. In fact, we could choose a more complicated manifold, say a Seifert fibered space, and still see elements commuting. For example, Seifert fibered spaces have non-trivial center. Thus, choosing $M$ to be a Seifert fibered space and $\alpha$ to be in the center of $\pi_1(M)$ will give the desired $a$ and $b$. Again, this has nothing to do with the isotopy classes of the knots $a$ and $b$.
-
Or just consider knots in the 3-sphere. – Misha Sep 7 '13 at 13:20 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8437223434448242, "perplexity": 152.7876124190434}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-06/segments/1422115900160.86/warc/CC-MAIN-20150124161140-00061-ip-10-180-212-252.ec2.internal.warc.gz"} |
http://www.transtutors.com/questions/statistics-429.htm | # statistics
homework statistics: Question 5 (ross 1.6): Show that E (FUG) = EF U EG In the attached files, you can have details. In the second question the word is "statistics" Question 5 (ross 1.6): Show that E (FUG) = EF U EG
Document Preview:
MGMT901 PROBABILITY THEORY & STATISTICS
Homework Assignment 1
Assigned on October 1 Due on October 8
1. Miller and Miller 1.30
2. Miller and Miller 1.44
3. A probability space consists of three parts:
(a) A sample space, S, which is the set of all possible outcomes.
(b) A set of events, F, where each event is a set containing zero or more outcomes.
(c) A function, P, that assigns probabilities to the events.
Hence, (S,F, P ) denotes a probability space.
Recall the third axiom of probability: If (any sequence of events) E1, E2, . . . are pairwise
disjoint (i.e., mutually exclusive), then
P[8
?
i=1
Ei]=
8
?
i=1
P(Ei).
Now, consider a more general setting where the events in a probability space (S,F, P )
are not necessarily pairwise disjoint. For any sequence of events E1, E2, . . . ? S, show
that
P[n
?
i=1
Ei]=
n
?
i=1
P(Ei).
4. Show that
P[n
?
i=1
Ei]=
n
?
i=1
(-1)i+1 ?
1=k1<...<ki=n
P(Ek1n. . . nEk1)
Hint: Proof by induction.
5. Ross 1.6
6. Ross 1.29
7. Miller and Miller 2.21
8. Miller and Miller 2.28
9. Ross 1.26
10. Miller and Miller 1.106
1
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A class consists of 13 women and 49 men. If a student is randomly selected, what is the probability that the student is a woman? | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8020093441009521, "perplexity": 1447.8933078818316}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-47/segments/1510934803944.17/warc/CC-MAIN-20171117204606-20171117224606-00517.warc.gz"} |
http://www.stata.com/statalist/archive/2011-10/msg01517.html | Notice: On March 31, it was announced that Statalist is moving from an email list to a forum. The old list will shut down on April 23, and its replacement, statalist.org is already up and running.
# Re: st: Data entry into TeX files (other than tables and graphs)
From Richard Herron To statalist@hsphsun2.harvard.edu Subject Re: st: Data entry into TeX files (other than tables and graphs) Date Mon, 31 Oct 2011 09:57:02 -0400
```Thanks for the lessons, Roger and Nick!
-parmest- is great and will come in handy for generating tables. But I
think for outputting scalars to TeX -file- will work best for me (code
below).
* begin code
file open temp using E:\temp.txt, write text replace
file write temp (e(N))
file close temp
* end code
Mon, Oct 31, 2011 at 07:46, Nick Cox <n.j.cox@durham.ac.uk> wrote:
> Roger's advice gives good positive suggestions.
>
> A secondary detail remains: Why didn't -outfile- work for Richard? In essence -outfile- requires a varlist, except that without one the entire dataset would be output. Richard's argument e(N) is clearly not a variable name, so is not a varlist. The rather cryptic message does show that -outfile- is trying hard to interpret what Richard writes as a variable name, but it can't turn e(N) into a varlist. Of course, anything you put into a variable first is fair game.
>
> In other contexts, -file- is closer to what Richard is seeking.
>
> Nick
> n.j.cox@durham.ac.uk
>
> Roger B. Newson
>
> This can be done using the -parmest- and -listtab- packages, both
> package, which you can also download from SSC. I would check the on-line
> help for these packages to see which does what you want.
>
> On 30/10/2011 01:56, Richard Herron wrote:
>
>> Can I save estimate parameters to a text file so that I can enter them
>> into a TeX file using \input{}? That is, I want to add the number of
>> observations or regression coefficients -- e(N) or e(b) -- in the text
>> of a paper without having to cut and paste. (I already know how to add
>> tables and graphs.)
>>
>> I can save a specific value to file with -outfile-.
>>
>> *begin code
>> sysuse auto, clear
>> outfile mpg using temp in 1/1, replace noquote
>> *end code
>>
>> But I can't save estimate results.
>>
>> *more code
>> regress mpg rep78
>> display e(N)
>> outfile e(N) using temp2, replace noquote
>> *end more code
>>
>> The last line gives the following error.
>>
>> factor variables and time-series operators not allowed
>> r(101);
>>
>> Is there a away to script all data entry into TeX files? Or do I have
>> to cut and paste? Thanks!
>
> *
> * For searches and help try:
> * http://www.stata.com/help.cgi?search
> * http://www.stata.com/support/statalist/faq
> * http://www.ats.ucla.edu/stat/stata/
>
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
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http://www.gathacognition.com/chapter/gcc24/bivariate-extremes:-models-and-statistical-decision?show=highlight | Gatha Cognition®
Perception, Learning and Reasoning
#### Bivariate Extremes: Models and Statistical Decision
Statistical Theory of Extremes
269-300
Statistical decision , Asymptotic approximation , Samples , Differentiable models , Logistic modes
Large samples, $\mathrm{ F^{n}( x,y ) }$ is replaced by an asymptotic approximation for statistical decision of extremes. The discussions decide the fitness and accuracy of those approximations. The differentiable models, non-differentiable models of statistical decision, intrinsic estimation of the dependence functions, ready-to-wear model and estimations of the association between the margins with some examples are discussed in this chapter. Differentiable models, the logistic one gives a good fit but shows the logistic and the natural models can be very close and difficult to separate for moderate samples. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9645779132843018, "perplexity": 2479.8500352791084}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-43/segments/1539583512750.15/warc/CC-MAIN-20181020121719-20181020143219-00303.warc.gz"} |