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https://en.wikipedia.org/wiki/Sense%20amplifier | In modern computer memory, a sense amplifier is one of the elements which make up the circuitry on a semiconductor memory chip (integrated circuit); the term itself dates back to the era of magnetic core memory. A sense amplifier is part of the read circuitry that is used when data is read from the memory; its role is to sense the low power signals from a bitline that represents a data bit (1 or 0) stored in a memory cell, and amplify the small voltage swing to recognizable logic levels so the data can be interpreted properly by logic outside the memory.
Modern sense-amplifier circuits consist of two to six (usually four) transistors, while early sense amplifiers for core memory sometimes contained as many as 13 transistors. There is one sense amplifier for each column of memory cells, so there are usually hundreds or thousands of identical sense amplifiers on a modern memory chip. As such, sense amplifiers are one of the few remaining analog circuits in a computer's memory subsystem.
Basic structure
Sense amplifier is required during the data read and refresh operation from the memory concerned.
Memory chip operation
The data in a semiconductor memory chip is stored in tiny circuits called memory cells. Sense Amplifiers are primarily applied in Volatile memory cells. The memory cells are either SRAM or DRAM cells which are laid out in rows and columns on the chip. Each line is attached to each cell in the row. The lines which run along the rows are called wordlines which are activated by putting a voltage on it. The lines which run along the columns are called bit-line and two such complementary bitlines are attached to a sense amplifier at the edge of the array. Number of sense amplifiers are of that of the "bitline' on the chip. Each cell lies at the intersection of a particular wordline and bitline, which can be used to "address" it. The data in the cells is read or written by the same bit-lines which run along the top of the rows and columns.
SRAM ope |
https://en.wikipedia.org/wiki/Groundwater%20flow%20equation | Used in hydrogeology, the groundwater flow equation is the mathematical relationship which is used to describe the flow of groundwater through an aquifer. The transient flow of groundwater is described by a form of the diffusion equation, similar to that used in heat transfer to describe the flow of heat in a solid (heat conduction). The steady-state flow of groundwater is described by a form of the Laplace equation, which is a form of potential flow and has analogs in numerous fields.
The groundwater flow equation is often derived for a small representative elemental volume (REV), where the properties of the medium are assumed to be effectively constant. A mass balance is done on the water flowing in and out of this small volume, the flux terms in the relationship being expressed in terms of head by using the constitutive equation called Darcy's law, which requires that the flow is laminar. Other approaches are based on Agent Based Models to incorporate the effect of complex aquifers such as karstic or fractured rocks (i.e. volcanic)
Mass balance
A mass balance must be performed, and used along with Darcy's law, to arrive at the transient groundwater flow equation. This balance is analogous to the energy balance used in heat transfer to arrive at the heat equation. It is simply a statement of accounting, that for a given control volume, aside from sources or sinks, mass cannot be created or destroyed. The conservation of mass states that, for a given increment of time (Δt), the difference between the mass flowing in across the boundaries, the mass flowing out across the boundaries, and the sources within the volume, is the change in storage.
Diffusion equation (transient flow)
Mass can be represented as density times volume, and under most conditions, water can be considered incompressible (density does not depend on pressure). The mass fluxes across the boundaries then become volume fluxes (as are found in Darcy's law). Using Taylor series to represent the in |
https://en.wikipedia.org/wiki/LC4MP | The Limited Capacity Model of Motivated Mediated Message Processing or LC4MP is an explanatory theory that assumes humans have a limited capacity for cognitive processing of information, as it associates with mediated message variables; moreover, they (viewers) are actively engaged in processing mediated information Like many mass communication theories, LC4MP is an amalgam that finds its origins in psychology. Specifically, this theory has its origins in the Limited Capacity Model for understanding cognitive information processing. The most fundamental assumptions of information processing are the three dimensions of cognitive processing. The three dimensions: 1) encoding, 2) storage, and 3) retrieval. This is how viewers get presented information into their heads. Messages can be processed under controlled conditions or they can be automatically elicited.
Limited capacity theory
When a message processor decides to pay attention to a message because it appeals to their interests, and they allocate resources to information processing, the controlled message engagement subprocess begins; conversely, when a message processor is cued automatically, and they are paying attention, the same process of allocating cognitive resources begins to elicit message processing. First, message engagement, which is a stimulus approach/avoidance interaction engages the appetitive and aversive cognitive subprocesses. In the most lay terms, these are basic fight or flight responses that happen in mere nanoseconds. This information then can report to sensor stores in the brain; and if it is useful, it will move to short term memory and long term memory.
Cognitive resources
There are several key concepts in the LC4MP: total resources, resources allocated, resources required, resources remaining, and resources available. Total resources refer to the total resources in the resource pool. Resources allocated refer to the resources that are actually available for a processing task. The |
https://en.wikipedia.org/wiki/Pad%20cratering | Pad cratering is a mechanically induced fracture in the resin between copper foil and outermost layer of fiberglass of a printed circuit board (PCB). It may be within the resin or at the resin to fiberglass interface.
The pad remains connected to the component (usually a Ball Grid Array, BGA) and leaves a "crater" on the surface of the printed circuit board.
Overview
Pad cratering most often occurs during dynamic mechanical events such as mechanical shock or board flexure due to In-circuit test (ICT), board depaneling, or connector insertion. However, pad cratering has also been known to occur during thermal shock or even thermal cycling. Susceptibility to pad cratering can be impacted by several factors such as: PCB thickness, PCB laminate material properties, component size and stiffness, component location, and solder alloy selection among other factors.
Testing
IPC-9708 provides three test methods to characterize the pad cratering of a component and PCBA: pin pull, ball pull, and ball shear testing. In the pin pull test a pin is soldered to pads and pulled until fracture. It is a useful test for all pad geometries and is sensitive to board design and materials. The ball pull test is specifically design for BGA components and has a large sensitivity to the solder alloy and joint formation. The ball shear test is also specified for BGA components and involves shearing the solder balls of the BGA. This test is typically the most convenient but is less sensitive to the design and material as compared to the ball pull test. Although IPC-9708 specifies procedures for each test type, the challenge is that no standard pass/fail criteria are defined. This is viewed as application-specific and must be defined by the user based on their design, environment, and reliability requirements.
Another applicable test method is IPC/JEDEC-9702, which is a monotonic bend test method used to characterize board level interconnects. This can be relevant for pad cratering resulting |
https://en.wikipedia.org/wiki/White%20ramus%20communicans | The white ramus communicans (: rami communicantes) from Latin ramus (branch) and communicans (communicating) is the preganglionic sympathetic outflow nerve tract from the spinal cord.
Each of the thoracic, and the first and second lumbar nerves contribute a white ramus communicans to the adjoining sympathetic ganglion, unlike the gray rami which are located at each spinal level. White rami communicantes contain both myelinated and unmyelinated preganglionic sympathetic fibers, (GVE and GVA). The white ramus appears white because there are more myelinated than unmyelinated fibers unlike the gray rami.
Structure
The white rami communicantes are the preganglionic sympathetic outflow from the spinal cord.
The cell bodies for the preganglionic sympathetic myelinated fibers in the white rami communicantes lie in the ipsilateral (same sided) intermediolateral cell column in the spinal cord which extends from T1-L2. These rami also contain general visceral afferent fibers (sensory from the organs) whose primary cell bodies reside dorsal root ganglia (which then synapse in the dorsal horn). The preganglionic sympathetic fibers will enter into the sympathetic trunk and either synapse at the ganglion on the same level, or travel up or down the sympathetic trunk to arrive at the correct spinal level for their action. Once they synapse in the sympathetic ganglion in the sympathetic trunk, they exit the trunk as gray rami to join the spinal nerve and innervate the appropriate structure. Even though the sympathetic trunk extends below L2, there are no more white rami communicantes below L2 because the intermediolateral cell column ends before this. The fibers of the sympathetic trunk above and below T1-L2 originate from white rami communicantes within T1-L2. Above and below T1-L2 there are only gray rami. Cell column are the important features of white rami communicates.
Additional Images
See also
Gray ramus communicans |
https://en.wikipedia.org/wiki/Morchella%20americana | Morchella americana is a species of fungus in the family Morchellaceae native to North America. Described as new to science in 2012, it is common east of the Rocky Mountains in a range stretching from Ontario south to Texas, Arkansas, Alabama, Georgia and South Carolina. In western North America, the species typically is found under hardwood, especially cottonwood trees in river bottoms, or with apple trees or ornamental ashes in urban settings. The specific epithet americana refers to its occurrence in North America.
In the Great Lakes region of eastern North America, the range of M. americana overlaps with M. ulmaria, which cannot be reliably distinguished from M. americana without DNA sampling.
Morchella americana, identified as phylogenetic species "Mes-4", has also been found in Turkey, France, and Germany, but is suspected of having been introduced there from North America.
In 2014, Richard et al. clarified the taxonomic status of this species, retaining the name Morchella americana of Clowez and Matherly(2012) over M. esculentoides. |
https://en.wikipedia.org/wiki/Motion%20ratio | The motion ratio of a mechanism is the ratio of the displacement of the point of interest to that of another point.
The most common example is in a vehicle's suspension, where it is used to describe the displacement and forces in the springs and shock absorbers. The force in the spring is (roughly) the vertical force at the contact patch divided by the motion ratio, and the spring rate is the wheel rate divided by the motion ratio squared.
This is described as the Installation Ratio in the reference. Motion ratio is the more common term in the industry, but sometimes is used to mean the inverse of the above definition.
Motion ratio in suspension of a vehicle describes the amount of shock travel for a given amount of wheel travel. Mathematically, it is the ratio of shock travel and wheel travel. The amount of force transmitted to the vehicle chassis reduces with increase in motion ratio. A motion ratio close to one is desired in the vehicle for better ride and comfort. One should know the desired wheel travel of the vehicle before calculating motion ratio, which depends much on the type of track the vehicle will run upon.
Selecting the appropriate ratio depends on multiple factors:
Bending moment: To reduce the bending moment the strut point should be close to the wheel.
Suspension stiffness: Suspensions tends to stiffen when the inclination of the shock absorber to horizontal tends to 90 deg.
Half-shafts: In rear suspensions, wheel travel is constrained by the universal joints of the half shafts. Design the motion ratio such that at maximum bounce and rebound shocks are the first components that bottom out by hitting bump stops. |
https://en.wikipedia.org/wiki/Java%20Development%20Kit | The Java Development Kit (JDK) is a distribution of Java Technology by Oracle Corporation. It implements the Java Language Specification (JLS) and the Java Virtual Machine Specification (JVMS) and provides the Standard Edition (SE) of the Java Application Programming Interface (API). It is derivative of the community driven OpenJDK which Oracle stewards. It provides software for working with Java applications. Examples of included software are the virtual machine, a compiler, performance monitoring tools, a debugger, and other utilities that Oracle considers useful for a Java programmer.
Oracle have released the current version of the software under the Oracle No-Fee Terms and Conditions (NFTC) license. Oracle release binaries for the x86-64 architecture for Windows, macOS, and Linux based operating systems, and for the aarch64 architecture for macOS and Linux. Previous versions have supported the Oracle Solaris operating system and SPARC architecture.
Oracle's primary implementation of the JVMS is known as the HotSpot (virtual machine).
JDK contents
The JDK has as its primary components a collection of programming tools, including:
appletviewer – this tool can be used to run and debug Java applets without a web browser
apt – the annotation-processing tool
extcheck – a utility that detects JAR file conflicts
idlj – the IDL-to-Java compiler. This utility generates Java bindings from a given Java IDL file.
jabswitch – the Java Access Bridge. Exposes assistive technologies on Microsoft Windows systems.
java – the loader for Java applications. This tool is an interpreter and can interpret the class files generated by the javac compiler. Now a single launcher is used for both development and deployment. The old deployment launcher, jre, comes with Sun JDK, and instead it has been replaced by this new java loader.
javac – the Java compiler, which converts source code into Java bytecode
javadoc – the documentation generator, which automatically generates docu |
https://en.wikipedia.org/wiki/Quipu | Quipu (also spelled khipu) are recording devices fashioned from strings historically used by a number of cultures in the region of Andean South America.
A quipu usually consisted of cotton or camelid fiber strings. The Inca people used them for collecting data and keeping records, monitoring tax obligations, collecting census records, calendrical information, and for military organization. The cords stored numeric and other values encoded as knots, often in a base ten positional system. A quipu could have only a few or thousands of cords. The configuration of the quipus has been "compared to string mops." Archaeological evidence has also shown the use of finely carved wood as a supplemental, and perhaps sturdier, base to which the color-coded cords would be attached. A relatively small number have survived.
Objects that can be identified unambiguously as quipus first appear in the archaeological record in the first millennium AD (though debated quipus are much earlier). They subsequently played a key part in the administration of the Kingdom of Cusco and later the Inca Empire, flourishing across the Andes from c. 1100 to 1532 AD. As the region was subsumed under the Spanish Empire, quipus were mostly replaced by European writing and numeral systems, and most quipu were identified as idolatrous and destroyed, but some Spaniards promoted the adaptation of the quipu recording system to the needs of the colonial administration, and some priests advocated the use of quipus for ecclesiastical purposes. In several modern villages, quipus have continued to be important items for the local community. It is unclear how many intact quipus still exist and where, as many have been stored away in mausoleums.
Knotted strings unrelated to quipu have been used to record information by the ancient Chinese, Tibetans and Japanese.
Quipu is the Spanish spelling and the most common spelling in English. Khipu (pronounced , plural: khipukuna) is the word for "knot" in Cusco Quechua. I |
https://en.wikipedia.org/wiki/European%20Ophthalmic%20Pathology%20Society | The European Ophthalmic Pathology Society is a learned society for advancing ophthalmic pathology, the study of the pathological basis of the diseases of the eye and its adnexa: the orbit, eyelids, conjunctiva and the lacrimal apparatus.
History
Founded in April 1962 at the premises of the Royal College of Surgeons of England in London, it was inspired by a similar learned society in the United States, the Verhoeff-Zimmerman Society, founded in 1945 and at that time called "The American Ophthalmic Pathology Club". In the early 1960s, ophthalmic pathology in Europe was not yet recognized as a distinct discipline and its practitioners had rarely had a formal training in the subject. Invitations to an inaugural meeting to be held in London were sent by Norman Ashton of London, S. Ry Andersen of Copenhagen, and Willem Manschot of Rotterdam to about 30 prospective members in May, 1961, together with details of what would be expected of them:
The members should have a special knowledge of ocular pathology.
They should be actively engaged in this work.
They should have adequate laboratory facilities.
They should have sufficient pathological material to provide interesting cases for the meetings.
The society is governed by its council, which is chaired by the society's president, according to a constitution and bye-laws. The members of the council and the president are elected from and by the Ordinary Members, the basic members of the society, who are themselves elected by existing Ordinary Members and are limited to 35 in number. The council is elected for three years and consists of the president, the corresponding secretary and the organizing secretary, the latter being responsible for organizing the next scientific meeting.
The current officers, elected in June 2017 and June 2019 (Organizing Secretary), are:
President: Tero Kivelä, MD (Finland)
Corresponding Secretary: Elisabeth Messmer, MD (Germany)
Organizing Secretary: Luis Alfaro, MD (Spain)
Functions and |
https://en.wikipedia.org/wiki/Coriell%20Institute%20for%20Medical%20Research | The Coriell Institute for Medical Research is an independent, non-profit biomedical research center dedicated to the study of the human genome. Coriell features programs in biobanking, personalized medicine, cell biology, cytogenetics, genotyping, and induced pluripotent stem cell science. Located in downtown Camden, New Jersey, the Institute has partnered with several prominent state and national health leaders, including Cooper University Hospital, the Cooper Medical School of Rowan University, the United States Air Force, the University of Pennsylvania, and Stanford University.
History
Coriell Institute was chartered in 1953 as the South Jersey Medical Research Foundation Laboratory and constructed facilities in 1956. The laboratory was later named for director Lewis L. Coriell, who had worked at the Camden Municipal Hospital and developed aseptic tissue culture techniques that ultimately allowed poliovirus to be grown in culture. Dr. Coriell also led the field trials for the resulting vaccine.
Operations
Biobanking
Regarded as one of the most diverse sources of cell lines and DNA available to the international research community, the Coriell Biorepositories maintain longstanding contracts with the National Institutes of Health and houses several significant collections, including the National Institute of General Medical Sciences Human Genetic Cell Repository, the National Institute of Neurological Disorders and Stroke Human Genetics DNA and Cell Line Repository, and the National Institute on Aging Cell Repository. The Institute houses cells for biotechnology companies and research foundations as well.
Research
In 2018, Coriell partnered with Cooper University Health Care and the Cooper Medical School of Rowan University to form the Camden Opioid Research Initiative (CORI), a state-funded research project studying risk factors for opioid use disorder. CORI utilizes a three-pronged approach: a study of chronic pain patients, a study of patients currently |
https://en.wikipedia.org/wiki/Help%20Crafter | Help Crafter is a Macintosh-based help authoring tool published by US-based company Putercraft LLC. It outputs a native Mac help bundle to be included in Mac applications.
The latest release is version 2.0. It is available from the Apple App Store.
Description
Help Crafter is a help authoring tool for Macintosh desktop applications. It allows users to create individual pages using its text editor, and organize pages in a tree structure. Each page can contain keywords and an abstract that allows users to find content anywhere in the Apple Help Viewer system application.
See also
List of help authoring tools
User assistance
External links
Technical communication
Technical communication tools
Online help |
https://en.wikipedia.org/wiki/Hercampuri | Hercampuri is a name applied to two species of Gentianella – Gentianella nitida and Gentianella alborosea. It has been used in Peruvian folk medicine since before the time of the Incas. These small shrubs are native to the high Andes of Peru. The Junin Province is a region of Peru that grows hercampuri.
Traditional use
The whole plant is used as an infusion. The roots are thin and yellow in color and the infusion of hercampuri also has a yellow color.
Chemical constituents
The infusion of hercampuri is one of the most bitter flavors of all herbs. The beneficial compounds that give hercampuri its unique taste contribute to the bitterness of the infusion. Chemical constituents isolated from Gentianella nitida include amaronitidin and nitiol. |
https://en.wikipedia.org/wiki/Brominated%20vegetable%20oil | Brominated vegetable oil (BVO) is a complex mixture of plant-derived triglycerides that have been reacted to contain atoms of the element bromine bonded to the molecules. Brominated vegetable oil is used primarily to help emulsify citrus-flavored soft drinks, preventing them from separating during distribution. Brominated vegetable oil has been used by the soft drink industry since 1931, generally at a level of about 8 ppm.
Careful control of the type of oil used allows bromination of it to produce BVO with a specific density of 1.33 g/mL, which is noticeably greater than that of water (1 g/mL). As a result, it can be mixed with less-dense flavoring agents such as citrus flavor oil to produce a resulting oil, the density of which matches that of water or other products. The droplets containing BVO remain suspended in the water rather than separating and floating at the surface.
Alternative food additives used for the same purpose include sucrose acetate isobutyrate (SAIB, E444) and glycerol ester of wood rosin (ester gum, E445).
Regulation and use
United States
In October 2023, California Governor Gavin Newsom approved a law that banned the manufacture, sale and distribution of brominated vegetable oil (along with three other additives). This is the first law in the U.S. to ban it, and will possibly have nationwide effects.
As of May 2023, New York is considering banning the use of brominated vegetable oil in foods because it acts as an endocrine disrupter, especially affecting the thyroid hormone and may also harm the reproductive system. California plans to ban the use of brominated vegetable oil in foods in 2027, following a bill signed into law in October 2023
In the United States, BVO was designated in 1958 as generally recognized as safe (GRAS), but this was withdrawn by the U.S. Food and Drug Administration in 1970. The U.S. Code of Federal Regulations currently imposes restrictions on the use of BVO as a food additive in the United States, limiting |
https://en.wikipedia.org/wiki/Army%20Geospatial%20Center | The Army Geospatial Center (AGC) (formerly Topographic Engineering Center (TEC)) is a Major Subordinate Command of the United States Army Corps of Engineers. It is located in Alexandria, Virginia, within the Humphreys Engineering Center adjacent to the Fort Belvoir military reservation.
The AGC reportedly coordinates, integrates, and synchronizes geospatial information and standards across the Army, develops and fields geospatial enterprise-enabled systems and capabilities to the Army and the Department of Defense, and provides direct geospatial support and products to Warfighters. Its Geospatial Research and Engineering Division, an Engineer Research and Development Center asset, conducts research and development into geospatial data collection, processing, exploitation, and dissemination in support of both civilian missions and missions of U.S. ground forces.
Subject matter expertise
AGC reportedly employs a workforce of more than 400, which includes Department of Defense civilians, contractors and military personnel. They support four program areas in support of the AGC mission:
Providing geospatial information products and services to US Army users.
Developing and fielding geospatial intelligence systems.
Synchronization of geospatial technology programs and policies for weapons system acquisition.
Research and development of geospatial technologies to characterize both physical and cultural environments encountered in military operations.
The AGC Director serves as the Geospatial Information Officer of the US Army.
Terrain data
AGC's primary area of expertise is in acquiring and depicting terrain data. It has developed products to rapidly characterize complex and urban terrain that include the use of the Rapid Terrain Visualization (RTV) and Urban Recon (UR) Advanced Concept Technology Demonstrations (ACTDs). These are embodied in the BuckEye program, bringing the collection of high resolution color imagery and coincidentally collected Light Detectio |
https://en.wikipedia.org/wiki/Thomas%E2%80%93Fermi%20equation | In mathematics, the Thomas–Fermi equation for the neutral atom is a second order non-linear ordinary differential equation, named after Llewellyn Thomas and Enrico Fermi, which can be derived by applying the Thomas–Fermi model to atoms. The equation reads
subject to the boundary conditions
If approaches zero as becomes large, this equation models the charge distribution of a neutral atom as a function of radius . Solutions where becomes zero at finite model positive ions. For solutions where becomes large and positive as becomes large, it can be interpreted as a model of a compressed atom, where the charge is squeezed into a smaller space. In this case the atom ends at the value of for which .
Transformations
Introducing the transformation converts the equation to
This equation is similar to Lane–Emden equation with polytropic index except the sign difference.
The original equation is invariant under the transformation . Hence, the equation can be made equidimensional by introducing into the equation, leading to
so that the substitution reduces the equation to
Treating as the dependent variable and as the independent variable, we can reduce the above equation to
But this first order equation has no known explicit solution, hence, the approach turns to either numerical or approximate methods.
Sommerfeld's approximation
The equation has a particular solution , which satisfies the boundary condition that as , but not the boundary condition y(0)=1. This particular solution is
Arnold Sommerfeld used this particular solution and provided an approximate solution which can satisfy the other boundary condition in 1932. If the transformation is introduced, the equation becomes
The particular solution in the transformed variable is then . So one assumes a solution of the form and if this is substituted in the above equation and the coefficients of are equated, one obtains the value for , which is given by the roots of the equation . The two ro |
https://en.wikipedia.org/wiki/Milliwatt%20test | A Milliwatt test (Milliwatt line) is a test method or test facility used in telecommunications to measure line quality and transmission loss between stations or points in an analog telephone system.
The test consists of transmitting an analog sinusoidal signal at the frequency of 1004 Hz with the power level of 0 (zero) dBm. By definition, this is the equivalent of a continuous power dissipation of 1 mW (milliWatt), i.e., the power consumed if a voltage of 0.775 V(RMS) is applied to a telephone line with 600 Ohm nominal impedance.
In the Bell System, central offices provided this type of service on a dedicated telephone number (102 type Milliwatt line) for remote subscriber line testing. In conjunction, a second line (type 100 line) provided quiet termination. Various types of test lines were called "100", "102", "104" etc., because these numbers accessed the test line in tandem offices in lieu of an area code.
In digital central office installations, the Milliwatt test facility was implemented using a synthesized version of the 1004 Hz signal, often called the digital milliwatt. +1-(503)-697-1000 is an example of such a Milliwatt from a digital central office.
See also
Loop around
Plant test number
Transmission level point |
https://en.wikipedia.org/wiki/Konrad%20Knopp | Konrad Hermann Theodor Knopp (22 July 1882 – 20 April 1957) was a German mathematician who worked on generalized limits and complex functions.
Family and education
Knopp was born in 1882 in Berlin to Paul Knopp (1845–1904), a businessman in manufacturing, and Helene (1857–1923), née Ostertun, whose own father was a butcher. Paul's hometown of Neustettin, then part of Germany, became Polish territory after the Second World War and is now called Szczecinek. In 1910, Konrad married the painter Gertrud Kressner (1879 - 1974). They had a daughter Ortrud Knopp (1911 - 1976), with the grandchildren Willfried Spohn (1944 - 2012), Herbert Spohn (*1946) und Wolfgang Spohn (*1950), and a son Ingolf Knopp (1915 – 2008), with the grandchildren Brigitte Knopp (*1952) and Werner Knopp (*1954).
Konrad was primarily educated in Berlin, with a brief sojourn at the University of Lausanne in 1901 for a single semester, before settling at the University of Berlin, where he remained for his doctoral studies. His doctoral thesis, entitled Grenzwerte von Reihen bei der Annäherung an die Konvergenzgrenze, was supervised by Schottky and Frobenius; he received his PhD in 1907.
Travels, teaching, and military career
Knopp traveled widely in Asia, taking teaching jobs in Nagasaki, Japan (1908-9), at the commercial college, and in Qingdao, China (1910–11), at the German-Chinese college there, and spending some time in India and China following his stay in Japan. His wedding to Kressner, the daughter of Colonel Karl Kressner and Hedwig Rebling, took place in Germany between these periods. After Qingdao he returned to Germany for good and taught at military academies while writing his habilitation thesis for Berlin University.
During the First World War he was an officer and was wounded at the beginning of the war, which resulted in his discharge from the army; by the autumn of 1914 he was teaching at Berlin University. In the following year he was appointed as an extraordinary professor a |
https://en.wikipedia.org/wiki/Mixing%20angle | In particle physics and quantum mechanics, mixing angles are the angles between two sets of (complex-valued) orthogonal basis vectors, or states, usually the eigenbases of two quantum mechanical operators. The choice of angles (parameterization) is not unique but based on convention.
Mathematics
The relation between two eigenbases is described completely by a unitary matrix, the analogue of a rotation matrix in a complex vector space. The number of degrees of freedom in this matrix is usually reduced by removing any excess complex phase from the transformation, since in most cases that is not a measurable quantity.
For two-dimensional vector space this reduces the matrix to a rotation matrix, which can be described completely by one mixing angle. In a three dimensional space there are three mixing angles and one additional complex phase parameter. Different conventions exist for how the three angles are defined, such as Euler angles.
Notable mixing angles
Some notable mixing angles in particle physics are:
Neutrino mixing angles (PMNS matrix), describing the mixing between the mass and flavour eigenstates of neutrinos, which explains neutrino oscillations
Quark mixing angles including the Cabbibo angle (CKM matrix), describing the mixing between the mass and flavour eigenstates of quarks
The Weinberg angle or weak mixing angle, describing the mixing between the electromagnetic and weak forces
Higgs mixing angle
Particle physics
Quantum mechanics |
https://en.wikipedia.org/wiki/ClickHouse | ClickHouse is an open-source column-oriented DBMS (columnar database management system) for online analytical processing (OLAP) that allows users to generate analytical reports using SQL queries in real-time. ClickHouse Inc. is headquartered in the San Francisco Bay Area with the subsidiary, ClickHouse B.V., based in Amsterdam, Netherlands.
In September 2021 in San Francisco, CA, ClickHouse incorporated to house the open source technology with an initial $50 million investment from Index Ventures and Benchmark Capital with participation by Yandex N.V. and others. On October 28, 2021 the company received Series B funding totaling $250 million at an valuation of $2 billion from Coatue Management, Altimeter Capital, and other investors. The company continues to build the open source project and engineering cloud technology.
History
ClickHouse’s technology was first developed over 10 years ago at Yandex, Russia's largest technology company. In 2009, Alexey Milovidov and developers started an experimental project to check the hypothesis if it was viable to generate analytical reports in real-time from non-aggregated data that is also constantly added in real-time. The developers spent 3 years to prove this hypothesis, and in 2012 ClickHouse launched in production for the first time to power Yandex.Metrica, the second-largest web analytics platform in the world, after Google Analytics.
Unlike custom data structures used before, ClickHouse was applicable more generally to work as a database management system. The power and utility of ClickHouse offered a true column-oriented DBMS, it allowed for systems to generate reports from petabytes of raw data with sub-second latencies. ClickHouse was widely adopted at Yandex including for Yandex.Tank load testing tool and Yandex.Market to monitor site accessibility and KPIs.
In 2016, the ClickHouse project was released as open-source software under the Apache 2 license in June 2016 to power analytical use cases around the globe |
https://en.wikipedia.org/wiki/Swish%20function | The swish function is a mathematical function defined as follows:
where β is either constant or a trainable parameter depending on the model. For β = 1, the function becomes equivalent to the Sigmoid Linear Unit or SiLU, first proposed alongside the GELU in 2016. The SiLU was later rediscovered in 2017 as the Sigmoid-weighted Linear Unit (SiL) function used in reinforcement learning. The SiLU/SiL was then rediscovered as the swish over a year after its initial discovery, originally proposed without the learnable parameter β, so that β implicitly equalled 1. The swish paper was then updated to propose the activation with the learnable parameter β, though researchers usually let β = 1 and do not use the learnable parameter β. For β = 0, the function turns into the scaled linear function f(x) = x/2. With β → ∞, the sigmoid component approaches a 0-1 function pointwise, so swish approaches the ReLU function pointwise. Thus, it can be viewed as a smoothing function which nonlinearly interpolates between a linear function and the ReLU function. This function uses non-monotonicity, and may have influenced the proposal of other activation functions with this property such as Mish.
When considering positive values, Swish is a particular case of sigmoid shrinkage function defined in (see the doubly parameterized sigmoid shrinkage form given by Equation (3) of this reference).
Applications
In 2017, after performing analysis on ImageNet data, researchers from Google indicated that using this function as an activation function in artificial neural networks improves the performance, compared to ReLU and sigmoid functions. It is believed that one reason for the improvement is that the swish function helps alleviate the vanishing gradient problem during backpropagation. |
https://en.wikipedia.org/wiki/Rheobase | Rheobase is a measure of membrane potential excitability. In neuroscience, rheobase is the minimal current amplitude of infinite duration (in a practical sense, about 300 milliseconds) that results in the depolarization threshold of the cell membranes being reached, such as an action potential or the contraction of a muscle. In Greek, the root rhe translates to "current or flow", and basi means "bottom or foundation": thus the rheobase is the minimum current that will produce an action potential or muscle contraction.
Rheobase can be best understood in the context of the strength-duration relationship (Fig. 1). The ease with which a membrane can be stimulated depends on two variables: the strength of the stimulus, and the duration for which the stimulus is applied. These variables are inversely related: as the strength of the applied current increases, the time required to stimulate the membrane decreases (and vice versa) to maintain a constant effect. Mathematically, rheobase is equivalent to half the current that needs to be applied for the duration of chronaxie, which is a strength-duration time constant that corresponds to the duration of time that elicits a response when the nerve is stimulated at twice rheobasic strength.
The strength-duration curve was first discovered by G. Weiss in 1901, but it was not until 1909 that Louis Lapicque coined the term rheobase. Many studies are being conducted in relation to rheobase values and the dynamic changes throughout maturation and between different nerve fibers. In the past strength-duration curves and rheobase determinations were used to assess nerve injury; today, they play a role in clinical identification of many neurological pathologies, including diabetic neuropathy, CIDP, Machado–Joseph disease, and ALS.
Strength-Duration Curve
The strength-duration time constant (chronaxie) and rheobase are parameters that describe the strength-duration curve—the curve that relates the intensity of a threshold stimulus to i |
https://en.wikipedia.org/wiki/Monoclonal%20antibody | A monoclonal antibody (mAb, more rarely called moAb) is an antibody produced from a cell lineage made by cloning a unique white blood cell. All subsequent antibodies derived this way trace back to a unique parent cell.
Monoclonal antibodies can have monovalent affinity, binding only to the same epitope (the part of an antigen that is recognized by the antibody). In contrast, polyclonal antibodies bind to multiple epitopes and are usually made by several different antibody-secreting plasma cell lineages. Bispecific monoclonal antibodies can also be engineered, by increasing the therapeutic targets of one monoclonal antibody to two epitopes.
It is possible to produce monoclonal antibodies that specifically bind to almost any suitable substance; they can then serve to detect or purify it. This capability has become an investigative tool in biochemistry, molecular biology, and medicine. Monoclonal antibodies are being used on a clinical level for both the diagnosis and therapy of several diseases. In 2020, the administration of monoclonal antibodies was authorized by several countries for treating moderate symptoms of COVID-19.
History
In the early 1900s, immunologist Paul Ehrlich proposed the idea of a Zauberkugel – "magic bullet", conceived of as a compound which selectively targeted a disease-causing organism, and could deliver a toxin for that organism. This underpinned the concept of monoclonal antibodies and monoclonal drug conjugates. Ehrlich and Élie Metchnikoff received the 1908 Nobel Prize for Physiology or Medicine for providing the theoretical basis for immunology.
By the 1970s, lymphocytes producing a single antibody were known, in the form of multiple myeloma – a cancer affecting B-cells. These abnormal antibodies or paraproteins were used to study the structure of antibodies, but it was not yet possible to produce identical antibodies specific to a given antigen. In 1973, Jerrold Schwaber described the production of monoclonal antibodies using human– |
https://en.wikipedia.org/wiki/My%20SAT%20Coach | My SAT Coach is a game on the Nintendo DS that helps students prepare for the SAT, a common standardized college-entry exam for American high school students.
The Princeton Review partnered with Ubisoft to create the game. The game features several learning exercises that progress through three stages of learning. It contains Mini-Game Drills, Personal Follow-Up and The Real Expert. The game is intended to help students improve their SAT scores.
Reception
IGN stated it was not too bad and that it is "simple and easy to follow;" reviewer Jack Devries's final opinion was that "If your school offers an SAT prep course, I would definitely recommend that over this title, but if you didn't plan on studying at all, then My SAT Coach is probably better than nothing." IGN gave it 6.5. |
https://en.wikipedia.org/wiki/Design%20tool | Design tools are objects, media, or computer programs, which can be used to design. They may influence the process of production, expression and perception of design ideas and therefore need to be applied skillfully.
Objects
New ideas can come by way of experimenting with tools and methods. Some designers explore ideas using pencil and paper. Others use many different mark-making tools and resources from computers to sculpture as a means of inspiring creativity. Traditionally, objects like pencil, compass, ruler, drawing triangle have been considered design tools and have been used to characterize design and designers. One reason for the success of traditional design tools such as pencil and paper is that these tools can be used without any special knowledge and their usage facilitates a continuous flow of thoughts.
Media
The appropriate development and presentation tools can substantially change how an audience perceives a project. The media used for design can be divided in two categories, visual and verbal. Conventionally, in areas like architecture, industrial design, or graphic design, visual media are considered more important than verbal media. In other areas like engineering, the use of verbal design media may be prevalent.
Visual
Visual design tools are, for example, gesture, sketch, drawing, scale model, perspective drawing, photograph, film, video. Eugene S. Ferguson's 1977 paper in Science, entitled "The mind's eye: Nonverbal thought in technology", is credited for clarifying the role of visual reasoning in the thinking process. In this article he reasoned that "Thinking with pictures is an essential strand in the intellectual history of technological development." He concludes his article with the following statement:
Much of the creative thought of the designers of our technological world is nonverbal, not easily reducible to words; its language is an object or a picture or a visual image in the mind. It is out of this kind of thinking that the cloc |
https://en.wikipedia.org/wiki/Friday%20Night%20Football%20%28AFL%29 | Friday Night Football is an Australian sports broadcast series is currently airing on the Seven Network.
History
Non-weekend night matches of Australian rules football first emerged in the late 1970s/early 1980s with the night series, a knock-out tournament featuring teams from across the country and run in parallel with the league seasons.
The first Victorian Football League matches on Friday nights were introduced in 1985. At this time, these games were irregularly scheduled, and all matches featured North Melbourne, but by 1987, Friday Night Football was played on a more regular basis, and other clubs began to host the games.
Friday night AFL is generally played in Melbourne, at either the Melbourne Cricket Ground or Docklands Stadium, but Sydney, Adelaide and Perth will generally host a few matches each year. It is less common for the games to be played in Sydney, Brisbane or the Gold Coast in order to avoid clashes with the National Rugby League, which is more popular in those cities. As it is the most lucrative broadcast timeslot of the weekend, matches between the better-performing clubs are scheduled on Friday night to ensure the games are of high quality. As recently as 2014, however, the Gold Coast Suns have pushed to be featured on Friday nights in 2015, citing their improved form in 2014.
Seven's commentary team includes James Brayshaw, Brian Taylor and Hamish McLachlan, with smaller roles involving Wayne Carey, Cameron Ling, Tim Watson, Matthew Richardson, Leigh Matthews and Luke Darcy.
Broadcast history
The Seven Network, which broadcast football for around 40 years before losing the rights after the 2001 season, was the first Australian network to broadcast Friday Night Football.
Between 2002–2006, the Nine Network had the rights to the Friday night broadcast; as the network also had the rights to the NRL, during those years in Melbourne, Adelaide and Perth, where by the AFL match would be broadcast first live at 8:30pm, followed by Nightline (o |
https://en.wikipedia.org/wiki/Atribacter | Atribacter is a genus of bacteria of the candidate phylum Atribacterota with one known species (Atribacter laminatus). |
https://en.wikipedia.org/wiki/Insup%20Lee | Insup Lee is the Cecilia Fitler Moore Professor in the Department of Computer and Information Science at the University of Pennsylvania, United States. He is also the Director and co-founder of the PRECISE Center.
Lee obtained his B.S. in mathematics from the University of North Carolina at Chapel Hill in 1977, followed by his M.S. and Ph.D. in Computer Science at the University of Wisconsin-Madison in 1983. That same year, he joined the University of Pennsylvania as an assistant professor. Lee's research is predominantly focused on cyber-physical systems (CPS), real-time computing, high-confidence medical devices, formal methods and tools, and run-time verification. Much of his recent work has been related to CPS security, particularly for medical devices. Lee is also a Fellow of the ACM, IEEE, and AAAS.
Awards and honors
Runtime Verification Test-of-Time Award, issued 2019 for ENTCS 2001 paper "Jav-MaC: Run-time Assurance Tool for Java Programs" (with Oleg Sokolsky, Sampath Kannan, Moonzoo Kim, and Mahesh Viswanathan).
IEEE TC-RTS Outstanding Technical Achievement and Leadership Award, issued Dec 2008.
The Edward M. Kennedy Award for Health Care Innovation, issued by CIMIT in 2007 for the Medical Device “PnP” Interoperability Team - Julian Goldman (leader), Dave Arney, Insup Lee, et al. |
https://en.wikipedia.org/wiki/International%20Conference%20on%20Communications | The International Conference on Communications (ICC) is an annual international academic conference organised by the Institute of Electrical and Electronics Engineers' Communications Society. The conference grew out of the Global Communications Conference (GLOBECOM) when, in 1965, the seventh GLOBECOM was sponsored by the Communications Society's predecessor as the "IEEE Communications Convention". The following year it adopted its current name and GLOBECOM was disbanded (it has since been revived). The conference was held in the United States until 1984 when it was held in Amsterdam; it has since been held in several other countries.
Some major telecommunications discoveries have been announced at ICC, such as the invention of turbo codes. In fact, this ground breaking paper had been submitted to ICC the previous year, but was rejected by the referees who thought the results too good to be true.
Recent ICCs have been attended by 2500–3000 people.
Conferences |
https://en.wikipedia.org/wiki/Kneser%27s%20theorem%20%28differential%20equations%29 | In mathematics, the Kneser theorem can refer to two distinct theorems in the field of ordinary differential equations:
the first one, named after Adolf Kneser, provides criteria to decide whether a differential equation is oscillating or not;
the other one, named after Hellmuth Kneser, is about the topology of the set of all solutions of an initial value problem with continuous right hand side.
Statement of the theorem due to A. Kneser
Consider an ordinary linear homogeneous differential equation of the form
with
continuous.
We say this equation is oscillating if it has a solution y with infinitely many zeros, and non-oscillating otherwise.
The theorem states that the equation is non-oscillating if
and oscillating if
Example
To illustrate the theorem consider
where is real and non-zero. According to the theorem, solutions will be oscillating or not depending on whether is positive (non-oscillating) or negative (oscillating) because
To find the solutions for this choice of , and verify the theorem for this example, substitute the 'Ansatz'
which gives
This means that (for non-zero ) the general solution is
where and are arbitrary constants.
It is not hard to see that for positive the solutions do not oscillate while for negative the identity
shows that they do.
The general result follows from this example by the Sturm–Picone comparison theorem.
Extensions
There are many extensions to this result, such as the Gesztesy–Ünal criterion.
Statement of the theorem due to H. Kneser
While Peano's existence theorem guarantees the existence of solutions of certain initial values problems with continuous right hand side, H. Kneser's theorem deals with the topology of the set of those solutions. Precisely, H. Kneser's theorem states the following:
Let be a continuous function on the region , and such that for all .
Given a real number satisfying , define the set as the set of points for which there is a solution of such that and . |
https://en.wikipedia.org/wiki/Niter%20kibbeh | Niter kibbeh, or niter qibe ( ), also called (in Tigrinya), is a seasoned, clarified butter used in Ethiopian and Eritrean cuisine. Its preparation is similar to that of ghee, but niter kibbeh is simmered with spices such as besobela (known as Ethiopian sacred basil), koseret, fenugreek, cumin, coriander, turmeric, Ethiopian cardamom (korarima), cinnamon, or nutmeg before straining, imparting a distinct, spicy aroma. The version using vegetable oil instead of butter is called yeqimem zeyet.
See also
List of Ethiopian dishes and foods
Kibbeh |
https://en.wikipedia.org/wiki/Equilibrative%20nucleoside%20transporter%20family | Members of the Equilibrative Nucleoside Transporter (ENT) Family (TC# 2.A.57) are transport proteins that are specific to nucleosides and nucleobases, and are part of the major facilitator superfamily. They generally possess at least 6, typically 10, transmembrane segments (TMSs) and are 300-600 amino acyl residues in length.
Function
ENTs, including those in parasitic protozoa, function in nucleoside and nucleobase uptake for salvage pathways of nucleotide synthesis and, in humans, are also responsible for the cellular uptake of nucleoside analogues used in the treatment of cancers and viral diseases. By regulating the concentration of adenosine available to cell surface receptors, mammalian ENTs additionally influence physiological processes ranging from cardiovascular activity to neurotransmission.
Human ENTs
In humans ENT are also known as SLC29, a group of plasmalemmal transport proteins which transport nucleoside substrates like adenosine into cells. There are four known human ENTs, designated ENT1, ENT2, ENT3, and ENT4. They are blocked by adenosine reuptake inhibitors like dipyridamole and dilazep, drugs used clinically for their vasodilatory properties.
The best-characterized members of the human Ent family, hENT1 and hENT2, possess similar broad permeant selectivities for purine and pyrimidine nucleosides, but hENT2 also efficiently transports nucleobases. hENT3 has a similar broad permeant selectivity for nucleosides and nucleobases and appears to function in intracellular membranes, including lysosomes. Gemcitabine, an anti-cancer drug, is transported by hENT1 and hENT3. hENT4 is uniquely selective for adenosine, and also transports a variety of organic cations.
Transport Reaction
The generalized transport reaction catalyzed by well characterized ENT family members is:
Nucleoside (out) → Nucleoside (in)
See also
Concentrative nucleoside transporter
Nucleoside transporter
Further reading |
https://en.wikipedia.org/wiki/Netherlands%20Physical%20Society | The Netherlands Physical Society (, NNV) is the professional society of physicists in the Netherlands and a member of the European Physical Society. Established in 1921, the goals of the society are to promote physics and to serve the interests of physicists in the Netherlands. Its main activities are publishing the Dutch physics journal Nederlands Tijdschrift voor Natuurkunde (NTvN), the organisation of an annual physics conference
and the co-development of the physics education curriculum in the Netherlands.
Sections
The NNV has the following sections that focus on either a particular field of physics or a specific topic of interest to physicists:
Atomic, Molecular and Optical physics
Energy and Climate
History and Foundations of Physics
Education and Communication
Physics of Plasmas and Gas discharges
Subatomic Physics |
https://en.wikipedia.org/wiki/Adjunction%20space | In mathematics, an adjunction space (or attaching space) is a common construction in topology where one topological space is attached or "glued" onto another. Specifically, let X and Y be topological spaces, and let A be a subspace of Y. Let f : A → X be a continuous map (called the attaching map). One forms the adjunction space X ∪f Y (sometimes also written as X +f Y) by taking the disjoint union of X and Y and identifying a with f(a) for all a in A. Formally,
where the equivalence relation ~ is generated by a ~ f(a) for all a in A, and the quotient is given the quotient topology. As a set, X ∪f Y consists of the disjoint union of X and (Y − A). The topology, however, is specified by the quotient construction.
Intuitively, one may think of Y as being glued onto X via the map f.
Examples
A common example of an adjunction space is given when Y is a closed n-ball (or cell) and A is the boundary of the ball, the (n−1)-sphere. Inductively attaching cells along their spherical boundaries to this space results in an example of a CW complex.
Adjunction spaces are also used to define connected sums of manifolds. Here, one first removes open balls from X and Y before attaching the boundaries of the removed balls along an attaching map.
If A is a space with one point then the adjunction is the wedge sum of X and Y.
If X is a space with one point then the adjunction is the quotient Y/A.
Properties
The continuous maps h : X ∪f Y → Z are in 1-1 correspondence with the pairs of continuous maps hX : X → Z and hY : Y → Z that satisfy hX(f(a))=hY(a) for all a in A.
In the case where A is a closed subspace of Y one can show that the map X → X ∪f Y is a closed embedding and (Y − A) → X ∪f Y is an open embedding.
Categorical description
The attaching construction is an example of a pushout in the category of topological spaces. That is to say, the adjunction space is universal with respect to the following commutative diagram:
Here i is the inclusion map and ϕX, ϕY are the map |
https://en.wikipedia.org/wiki/Rachev%20ratio | The Rachev Ratio (or R-Ratio) is a risk-return performance measure of an investment asset, portfolio, or strategy. It was devised by Dr. Svetlozar Rachev and has been extensively studied in quantitative finance. Unlike the reward-to-variability ratios, such as Sharpe ratio and Sortino ratio, the Rachev ratio is a reward-to-risk ratio, which is designed to measure the right tail reward potential relative to the left tail risk in a non-Gaussian setting. Intuitively, it represents the potential for extreme positive returns compared to the risk of extreme losses (negative returns), at a rarity frequency q (quantile level) defined by the user.
The ratio is defined as the Expected Tail Return (ETR) in the best q% cases divided by the Expected tail loss (ETL) in the worst q% cases. The ETL is the average loss incurred when losses exceed the Value at Risk at a predefined quantile level. The ETR, defined by symmetry to the ETL, is the average profit gained when profits exceed the Profit at risk at a predefined quantile level.
For more tailored applications, the generalized Rachev Ratio has been defined with different powers and/or different confidence levels of the ETR and ETL.
Definition
According to its original version introduced by the authors in 2004, the Rachev ratio is defined as:
or, alternatively,
where and belong to , and in the symmetric case: . is the risk-free rate of return and presents the portfolio return. The ETL is the expected tail loss, also known as conditional value at risk (CVaR), is defined as:
and
is the value at risk (VaR) of the random return .
Thus, the ETL can be interpreted as the average loss beyond VaR:
.
The generalized Rachev ratio is the ratio between the power CVaR of the opposite of the excess return at a given confidence level and the power CVaR of the excess return at another confidence level. That is,
where is the power CVaR of , and is a positive constant. The main advantage of the generalized Rachev ratio over t |
https://en.wikipedia.org/wiki/Enneagram%20%28geometry%29 | In geometry, an enneagram (🟙 U+1F7D9) is a nine-pointed plane figure. It is sometimes called a nonagram, nonangle, or enneagon.
The word 'enneagram' combines the numeral prefix ennea- with the Greek suffix -gram. The gram suffix derives from γραμμῆς (grammēs) meaning a line.
Regular enneagram
A regular enneagram is a 9-sided star polygon. It is constructed using the same points as the regular enneagon, but the points are connected in fixed steps. Two forms of regular enneagram exist:
One form connects every second point and is represented by the Schläfli symbol {9/2}.
The other form connects every fourth point and is represented by the Schläfli symbol {9/4}.
There is also a star figure, {9/3} or 3{3}, made from the regular enneagon points but connected as a compound of three equilateral triangles. (If the triangles are alternately interlaced, this results in a Brunnian link.) This star figure is sometimes known as the star of Goliath, after {6/2} or 2{3}, the star of David.
Other enneagram figures
The nine-pointed star or enneagram can also symbolize the nine gifts or fruits of the Holy Spirit.
In popular culture
The heavy metal band Slipknot previously used the {9/3} star figure enneagram and currently uses the {9/4} polygon as a symbol. The prior figure can be seen on the cover of All Hope Is Gone.
See also
List of regular star polygons
Baháʼí symbols |
https://en.wikipedia.org/wiki/2-Methylisoborneol | 2-Methylisoborneol (MIB) is an irregular monoterpene derived from the universal monoterpene precursor geranyl pyrophosphate. MIB and the irregular sesquiterpene geosmin together account for the majority of biologically-caused taste and odor outbreaks in drinking water worldwide. MIB has a distinct earthy or musty odor, which most people can easily smell. The odor detection threshold of MIB is very low, ranging from 0.002 to 0.02 micrograms per liter in water. MIB is also a factor in cork taint in winemaking.
MIB is produced by various blue-green algae (cyanobacteria) and filamentous bacteria in the class Actinomycetia, and also some other prokaryotes and eukaryotes. The main genera in the cyanobacteria that have been shown to produce MIB include Oscillatoria, Phormidium, and Planktothrix, while the main genus in the Actinomycetia that produces MIB is Streptomyces. They give a musty or earthy odor that can be quite strong if an algal bloom is present. Subsequent death of the microorganisms will release MIB that is trapped in the cells. Along with geosmin, the off flavors that result are issues in the seafood industry. This chemical is the major cause of "muddy" or "dirt" flavors in catfish and crawfish.
Rhodococcus and Comamonas bacteria can degrade 2-methylisoborneol. |
https://en.wikipedia.org/wiki/List%20of%20Unified%20Modeling%20Language%20tools | This article compares UML tools. UML tools are software applications which support some functions of the Unified Modeling Language.
General
Features
See also
List of requirements engineering tools |
https://en.wikipedia.org/wiki/WLIW%20%28TV%29 | WLIW (channel 21) is a secondary PBS member television station licensed to Garden City, New York, United States, serving the New York City television market. It is owned by The WNET Group alongside the area's primary PBS member, Newark, New Jersey–licensed WNET (channel 13); two Class A stations which share spectrum with WNET, WNDT-CD (channel 14) and WMBQ-CD (channel 46); and WLIW-FM (88.3) in Southampton. Through an outsourcing agreement, The WNET Group also operates New Jersey's PBS state network NJ PBS and the website NJ Spotlight.
WLIW and WNET share studios at One Worldwide Plaza in Midtown Manhattan with an auxiliary street-level studio in the Lincoln Center complex on Manhattan's Upper West Side. WLIW's transmitter is located at One World Trade Center; the station also maintains a production studio at its former transmitter site in Plainview, New York. WLIW's multiplex is New York's high-power ATSC 3.0 (NextGen TV) television station and also broadcasts WMBQ-CD.
WLIW was established in 1969 as the first television station on Long Island. Originally operated on a tight budget, the station had no permanent studio facilities for nearly a decade. In the 1980s and 1990s, increasing cable television coverage led to the expansion of WLIW into a regional service that was the smaller competitor to WNET, the nation's largest public TV station, and the station increased its own programming efforts. However, some critics felt that this shift deemphasized the station's Long Island identity. In 2003, WLIW and WNET merged, completing an 18-month process. As part of the WNET Group, WLIW maintains a separate vice president and general manager, Diane Masciale, who is in charge of the entire group's locally oriented television production.
History
Early history
The Nassau County Board of Supervisors voted on February 14, 1968, to provide funding to set up an educational television station on Long Island, thereby also accessing matching funds from the New York state governme |
https://en.wikipedia.org/wiki/Lipid%20microdomain | Lipid microdomains are formed when lipids undergo lateral phase separations yielding stable coexisting lamellar domains. These phase separations can be induced by changes in temperature, pressure, ionic strength or by the addition of divalent cations or proteins. The question of whether such lipid microdomains observed in model lipid systems also exist in biomembranes had motivated considerable research efforts. Lipid domains are not readily isolated and examined as unique species, in contrast to the examples of lateral heterogeneity.
One can disrupt the membrane and demonstrate a heterogeneous range of composition in the population of the resulting vesicles or fragments. Electron microscopy can also be used to demonstrate lateral inhomogeneities in biomembranes.
Often, lateral heterogeneity has been inferred from biophysical techniques where the observed signal indicates multiple populations rather than the expected homogeneous population. An example of this is the measurement of the diffusion coefficient of a fluorescent lipid analog in soybean protoplasts. Membrane microheterogeneity is sometimes inferred from the behavior of enzymes, where the enzymatic activity does not appear to be correlated with the average lipid physical state exhibited by the bulk of the membrane. Often, the methods suggest regions with different lipid fluidity, as would be expected of coexisting gel and liquid crystalline phases within the biomembrane. This is also the conclusion of a series of studies where differential effects of perturbation caused by cis and trans fatty acids are interpreted in terms of preferential partitioning of the two liquid crystalline and gel-like domains.
See also
Biochemistry
Essential fatty acid
Lipid raft
PIP2 domain
Lipid signaling
Saturated and unsaturated compounds |
https://en.wikipedia.org/wiki/Beth%20number | In mathematics, particularly in set theory, the beth numbers are a certain sequence of infinite cardinal numbers (also known as transfinite numbers), conventionally written , where is the second Hebrew letter (beth). The beth numbers are related to the aleph numbers (), but unless the generalized continuum hypothesis is true, there are numbers indexed by that are not indexed by .
Definition
Beth numbers are defined by transfinite recursion:
where is an ordinal and is a limit ordinal.
The cardinal is the cardinality of any countably infinite set such as the set of natural numbers, so that .
Let be an ordinal, and be a set with cardinality . Then,
denotes the power set of (i.e., the set of all subsets of ),
the set denotes the set of all functions from to {0,1},
the cardinal is the result of cardinal exponentiation, and
is the cardinality of the power set of .
Given this definition,
are respectively the cardinalities of
so that the second beth number is equal to , the cardinality of the continuum (the cardinality of the set of the real numbers), and the third beth number is the cardinality of the power set of the continuum.
Because of Cantor's theorem, each set in the preceding sequence has cardinality strictly greater than the one preceding it. For infinite limit ordinals, λ, the corresponding beth number is defined to be the supremum of the beth numbers for all ordinals strictly smaller than λ:
One can also show that the von Neumann universes have cardinality .
Relation to the aleph numbers
Assuming the axiom of choice, infinite cardinalities are linearly ordered; no two cardinalities can fail to be comparable. Thus, since by definition no infinite cardinalities are between and , it follows that
Repeating this argument (see transfinite induction) yields
for all ordinals .
The continuum hypothesis is equivalent to
The generalized continuum hypothesis says the sequence of beth numbers thus defined is the same as the seque |
https://en.wikipedia.org/wiki/Irene%20Manton%20Prize | The Irene Manton Prize of the Linnean Society of London is awarded annually for the "best thesis in botany examined for a doctorate of philosophy during a single academic year" in the United Kingdom.
The prize is named in honour of Irene Manton FRS, the first female president of the Linnean Society of London. She pioneered the biological use of electron microscopy. Her work revealed the structure of the flagellum and cilia, which are central to many systems of cellular motility.
Recipients of the Irene Manton Prize
Sophie Harrington, University of East Anglia (2021)
James Clark (2020)
Leanne Melbourne (2019) University of Bristol; The effect of environmental change on the structure, composition and subsequently the structural integrity of un-attached corallines
Sandy Hetherington (2018) University of Oxford; Evolution and morphology of lycophyte root systems
Shanna Ludwig (2015) University of Bristol; Ecological and evolutionary genetics, focusing on reproductive biology and speciation in diploid and polyploid Sorbus populations
Simon Renny-Byfield (2014) Queen Mary, University of London; Evolution of repetitive DNA in angiosperms: Examples from Nicotiana
Janine Pendleton (2013) University of Sheffield; Carboniferous plants and spores from the Bristol Coalfield
Alexander S T Papadopulos (2012) Imperial College London;
Tiina Sarkinen (2011)
Christopher Thorogood (2010)
Chris Yesson (2009)
James Clarkson and Silvia Pressel (2008)
Lionel Navarro (2007); University of East Anglia; Plant innate immunity and bacterial pathogenesis
Yuki Yasumura (2006)
Alex Wortley (2005)
Mark Clegg (2003)
Julie King (2002)
Alison Gwen Roberts (2001)
James Edward Richardson (2000)
Melissa Spielman (1999)
Alexander Weir (1998)
Colin Edward Hughes (1997)
Dorothy Steane (1996)
Sally Glockling (1995)
William Justin Goodrich (1993)
Sharon Anita Robinson and Robert Winning Scotland (1992)
not awarded (1991)
Christine Masterson (1990)
See also
List of biology awards |
https://en.wikipedia.org/wiki/List%20of%20dates%20predicted%20for%20apocalyptic%20events | Predictions of apocalyptic events that would result in the extinction of humanity, a collapse of civilization, or the destruction of the planet have been made since at least the beginning of the Common Era. Most predictions are related to Abrahamic religions, often standing for or similar to the eschatological events described in their scriptures. Christian predictions typically refer to events like the rapture, the Great Tribulation, the Last Judgment, and the Second Coming of Christ. Many religious-related end-time events are predicted to occur within the lifetime of the person making the prediction, who often quote the Bible, and in particular the New Testament, as either the primary or exclusive source for the predictions. This often takes the form of mathematical calculations, such as trying to calculate the point where it will have been 6000 years since the supposed creation of the Earth by the Abrahamic God, which according to the Talmud marks the deadline for the Messiah to appear. Predictions of the end from natural events have also been theorised by various scientists and scientific groups. While these disasters are generally accepted within the scientific community as plausible "end of the world" scenarios, the events and phenomena are not expected to occur for hundreds of thousands or even billions of years from now.
Little research has been done into why people make apocalyptic predictions. Historically, it has been done for reasons such as diverting attention from actual crises like poverty and war, pushing political agendas, and promoting hatred of certain groups; antisemitism was a popular theme of Christian apocalyptic predictions in medieval times, while French and Lutheran depictions of the apocalypse were known to feature English and Catholic antagonists respectively. According to psychologists, possible explanations for why people believe in modern apocalyptic predictions include mentally reducing the actual danger in the world to a single and |
https://en.wikipedia.org/wiki/Supersolvable%20arrangement | In mathematics, a supersolvable arrangement is a hyperplane arrangement which has a maximal flag with only modular elements. Equivalently, the intersection semilattice of the arrangement is a
supersolvable lattice, in the sense of Richard P. Stanley. As shown by Hiroaki Terao,
a complex hyperplane arrangement is supersolvable if and only if its complement is fiber-type.
Examples include arrangements associated with Coxeter groups of type A and B.
It is known that the Orlik–Solomon algebra of a supersolvable arrangement is a Koszul algebra; whether the converse is true is an open problem. |
https://en.wikipedia.org/wiki/List%20of%20Macanese%20flags | This is a list of flags of Macau.
Official Flag
Prefecture
Historical Flags
Governor of Macau
Proposed flags |
https://en.wikipedia.org/wiki/Windwatt | A Windwatt is a mudflat exposed as a result of wind action on water. They occur especially in the Western Pomerania Lagoon Area National Park on Germany's Baltic Sea coast. The term is German.
Unlike the Wadden Sea along Europe's North Sea coast, the shallow water zones of the Western Pomerania Lagoon Area National Park are largely unaffected by oceanic tides. When there are strong winds in a certain direction, however, water is driven out of the lagoons (the so-called bodden) into the Baltic Sea, so that several particularly shallow areas of mud become exposed and dry out. The water flows back when the wind turns again.
These Windwatten are a major source of food for migrating birds in the autumn. For the Crane, which cross Western Pomeranian bodden country during migration, the Windwatten are one of the most important resting areas in Western Europe. |
https://en.wikipedia.org/wiki/Milkweed%20yellows%20phytoplasma | Milkweed yellows phytoplasma is a strain of phytoplasma in the class Mollicutes, a class of bacteria distinguished by the absence of a cell wall. The phytoplasma strain is denoted by the acronym MW1.
Like all phytoplasmas, milkweed yellows phytoplasma is an obligate intracellular parasite, that is, it can not live outside of host cells. It spreads by means of an insect vector, the identity of which is unknown. In general, phytoplasmas spread via leafhoppers and other sap-sucking insects that transmit the pathogen from one host plant to another.
Taxonomy
In 1994, two strains of phytoplasmas that infect the common milkweed Asclepias syriaca (denoted MW1 and MW2) were shown to be members of the X-disease group (16Sr group III). Milkweed yellows phytoplasma (MW1) was later found to be a 'Candidatus Phytoplasma pruni'-related strain of phytoplasma belonging to subgroup F (16SrIII-F). Other phytoplasmas in subgroup 16SrIII-F include Vaccinium witches' broom phytoplasma (VAC, VacWB) and potato purple top phytoplasma (AKpot7). , milkweed yellows phytoplasma has not been formally described.
Milkweed yellows
Milkweed yellows is an infectious disease of milkweeds caused by the milkweed yellows phytoplasma. Other diseases caused by pathogens in subgroup 16SrIII-F include Vaccinium witches' broom, potato purple top, and a greening disorder of Trillium grandiflorum and other Trillium species.
Hosts
The common milkweed Asclepias syriaca and the periwinkle Catharanthus roseus are known plant hosts for milkweed yellows phytoplasma. The insect host species for milkweed yellows is not known.
See also
Aster yellows
Elm yellows
Grapevine yellows
Bibliography |
https://en.wikipedia.org/wiki/Katz%27s%20back-off%20model | Katz back-off is a generative n-gram language model that estimates the conditional probability of a word given its history in the n-gram. It accomplishes this estimation by backing off through progressively shorter history models under certain conditions. By doing so, the model with the most reliable information about a given history is used to provide the better results.
The model was introduced in 1987 by Slava M. Katz. Prior to that, n-gram language models were constructed by training individual models for different n-gram orders using maximum likelihood estimation and then interpolating them together.
Method
The equation for Katz's back-off model is:
where
C(x) = number of times x appears in training
wi = ith word in the given context
Essentially, this means that if the n-gram has been seen more than k times in training, the conditional probability of a word given its history is proportional to the maximum likelihood estimate of that n-gram. Otherwise, the conditional probability is equal to the back-off conditional probability of the (n − 1)-gram.
The more difficult part is determining the values for k, d and α.
is the least important of the parameters. It is usually chosen to be 0. However, empirical testing may find better values for k.
is typically the amount of discounting found by Good–Turing estimation. In other words, if Good–Turing estimates as , then
To compute , it is useful to first define a quantity β, which is the left-over probability mass for the (n − 1)-gram:
Then the back-off weight, α, is computed as follows:
The above formula only applies if there is data for the "(n − 1)-gram". If not, the algorithm skips n-1 entirely and uses the Katz estimate for n-2. (and so on until an n-gram with data is found)
Discussion
This model generally works well in practice, but fails in some circumstances. For example, suppose that the bigram "a b" and the unigram "c" are very common, but the trigram "a b c" is never seen. Since "a b" and "c" |
https://en.wikipedia.org/wiki/Renewable%20security | Renewable Security was a concept that evolved after the repeated hacks of analogue TV encryption systems in the late 1980s. Simply stated, rather than completely replacing a hacked TV encryption system, only part of it would have to be replaced to make it secure again.
Embedded secure processor
The decoders at that time often contained all of the conditional access control data in a microcontroller. This data consisted generally of the decoder's identity, the subscriber's identity number and subscription data. When the decoder was hacked, the whole system was effectively compromised as other subscriber identity data could be substituted and the hackers had control. This security model also more commonly known as the Embedded Secure Processor model as the secure processor, the microcontroller, was embedded in the decoder itself.
Detachable secure processor
The systems manufacturers countered with the Detachable Secure Processor model. In this security model, the decoder itself would not be the critical part of the system. The subscriber identity data and subscription details would be stored in a smartcard - the Detachable Secure Processor. Any compromise of the smartcard could then be countered by issuing a new, more secure, smartcard to subscribers.
Advantages and disadvantages
Renewable Security is good in theory. It provides hackers with a moving target rather than a stationary one. In the VideoCrypt system, the initial expectation was that the smartcards would be replaced every six months thus making the emergence of a pirate smartcard less likely. In reality, changing or upgrading the smartcards on a widely used TV Encryption system can be expensive and is done as infrequently as possible. |
https://en.wikipedia.org/wiki/Golgi%20matrix | The Golgi matrix is a collection of proteins involved in the structure and function of the Golgi apparatus. The matrix was first isolated in 1994 as an amorphous collection of 12 proteins that remained associated together in the presence of detergent (which removed Golgi membranes) and 150 mM NaCl (which removed weakly associated proteins). Treatment with a protease enzyme removed the matrix, which confirmed the importance of proteins for the matrix structure. Modern freeze etch electron microscopy (EM) clearly shows a mesh connecting Golgi cisternae and associated vesicles. Further support for the existence of a matrix comes from EM images showing that ribosomes are excluded from regions between and near Golgi cisternae.
Structure and function
The first individual protein component of the matrix was identified in 1995 as Golgin A2 (then called GM130). Since then, many other golgin family proteins have been found to be in the Golgi matrix and are associated with the Golgi membranes in a variety of ways. For example, GMAP210 (Golgi Microtubule Associated Protein 210) has an ALPS (Amphipathic Lipid-Packing Sensor) motif in the N-termal 38 amino acids and an ARF1-binding domain called GRAB (Grip-Related Arf-Binding) at the C-terminus. Thus, the GRAB-domain can bind indirectly to Golgi cisternae and its ALPS motif can tether vesicles.
Golgins have coiled-coil domains and are thus predicted to have elongated structures up to 200 nm in length. Most are peripheral membrane proteins attached at one end to Golgi membranes. They have flexible regions between the coiled-coil domains, which make them ideal candidates for mediating the dynamic vesicle docking to Golgi cisternae and dynamic structure of the Golgi itself.
Golgi reassembly-stacking proteins are an evolutionarily conserved family of proteins in the Golgi matrix. GRASP65 and GRASP55 are the 2 human GRASPs. These proteins were named from their requirement for accurate Golgi reassembly during an in vitro assay, but |
https://en.wikipedia.org/wiki/Satisfiability | In mathematical logic, a formula is satisfiable if it is true under some assignment of values to its variables. For example, the formula is satisfiable because it is true when and , while the formula is not satisfiable over the integers. The dual concept to satisfiability is validity; a formula is valid if every assignment of values to its variables makes the formula true. For example, is valid over the integers, but is not.
Formally, satisfiability is studied with respect to a fixed logic defining the syntax of allowed symbols, such as first-order logic, second-order logic or propositional logic. Rather than being syntactic, however, satisfiability is a semantic property because it relates to the meaning of the symbols, for example, the meaning of in a formula such as . Formally, we define an interpretation (or model) to be an assignment of values to the variables and an assignment of meaning to all other non-logical symbols, and a formula is said to be satisfiable if there is some interpretation which makes it true. While this allows non-standard interpretations of symbols such as , one can restrict their meaning by providing additional axioms. The satisfiability modulo theories problem considers satisfiability of a formula with respect to a formal theory, which is a (finite or infinite) set of axioms.
Satisfiability and validity are defined for a single formula, but can be generalized to an arbitrary theory or set of formulas: a theory is satisfiable if at least one interpretation makes every formula in the theory true, and valid if every formula is true in every interpretation. For example, theories of arithmetic such as Peano arithmetic are satisfiable because they are true in the natural numbers. This concept is closely related to the consistency of a theory, and in fact is equivalent to consistency for first-order logic, a result known as Gödel's completeness theorem. The negation of satisfiability is unsatisfiability, and the negation of validity is |
https://en.wikipedia.org/wiki/Gene%20knock-in | In molecular cloning and biology, a gene knock-in (abbreviation: KI) refers to a genetic engineering method that involves the one-for-one substitution of DNA sequence information in a genetic locus or the insertion of sequence information not found within the locus. Typically, this is done in mice since the technology for this process is more refined and there is a high degree of shared sequence complexity between mice and humans. The difference between knock-in technology and traditional transgenic techniques is that a knock-in involves a gene inserted into a specific locus, and is thus a "targeted" insertion. It is the opposite of gene knockout.
A common use of knock-in technology is for the creation of disease models. It is a technique by which scientific investigators may study the function of the regulatory machinery (e.g. promoters) that governs the expression of the natural gene being replaced. This is accomplished by observing the new phenotype of the organism in question. The BACs and YACs are used in this case so that large fragments can be transferred.
Technique
Gene knock-in originated as a slight modification of the original knockout technique developed by Martin Evans, Oliver Smithies, and Mario Capecchi. Traditionally, knock-in techniques have relied on homologous recombination to drive targeted gene replacement, although other methods using a transposon-mediated system to insert the target gene have been developed. The use of loxP flanking sites that become excised upon expression of Cre recombinase with gene vectors is an example of this. Embryonic stem cells with the modification of interest are then implanted into a viable blastocyst, which will grow into a mature chimeric mouse with some cells having the original blastocyst cell genetic information and other cells having the modifications introduced to the embryonic stem cells. Subsequent offspring of the chimeric mouse will then have the gene knock-in.
Gene knock-in has allowed, for the firs |
https://en.wikipedia.org/wiki/Electrostatic%20spray-assisted%20vapour%20deposition | Electrostatic spray-assisted vapour deposition (ESAVD) is a technique (developed by a company called IMPT) to deposit both thin and thick layers of a coating onto various substrates. In simple terms chemical precursors are sprayed across an electrostatic field towards a heated substrate, the chemicals undergo a controlled chemical reaction and are deposited on the substrate as the required coating. Electrostatic spraying techniques were developed in the 1950s for the spraying of ionised particles on to charged or heated substrates.
ESAVD (branded by IMPT as Layatec) is used for many applications in many markets including:
Thermal barrier coatings for jet engine turbine blades
Various thin layers in the manufacture of flat panel displays and photovoltaic panels, CIGS and CZTS-based thin-film solar cells.
Electronic components
Biomedical coatings
Glass coatings (such as self-cleaning)
Corrosion protection coatings
The process has advantages over other techniques for layer deposition (plasma, electron-beam) in that it does not require the use of any vacuum, electron beam or plasma so reduces the manufacturing costs. It also uses less power and raw materials making it more environmentally friendly. Also the use of the electrostatic field means that the process can coat complex 3D parts easily. |
https://en.wikipedia.org/wiki/Glycoside%20hydrolase%20family%2043 | In molecular biology, glycoside hydrolase family 43 is a family of glycoside hydrolases.
Glycoside hydrolases are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycoside hydrolases, based on sequence similarity, has led to the definition of >100 different families. This classification is available on the CAZy web site, and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes.
Glycoside hydrolase family 43 CAZY GH_43 includes enzymes with the following activities, beta-xylosidase (), alpha-L-arabinofuranosidase (); arabinanase (), and xylanase (). The structure of arabinanase Arb43A from Cellvibrio japonicus reveals a five-bladed beta-propeller fold. A long V-shaped groove, partially enclosed at one end, forms a single extended substrate-binding surface across the face of the propeller. |
https://en.wikipedia.org/wiki/Prefactoring | Prefactoring is the application of experience to the creation of new software systems. Its relationship to its namesake refactoring is that lessons learned from refactoring are part of that experience.
Experience is captured in guidelines that can be applied to a development process. The guidelines have come from a number of sources, including Jerry Weinberg, Norm Kerth, and Scott Ambler.
These guidelines include:
"When you're abstract, be abstract all the way"
"Splitters can be lumped more easily than lumpers can be split"
"Use the client’s language" |
https://en.wikipedia.org/wiki/OEDN | OEDN is an OpenCable Application Platform (OCAP) EBIF Developer Network that was founded in October, 2007. It is an online developer network for the promotion of Interactive Television application and service development on digital cable television.
The goal of the network is to support the emerging and long-term needs of software engineers and product teams who are building OCAP (tru2way) and EBIF applications. The goal is to run it not only on digital cable television, but also converged applications and services spanning mobile and broadband devices.
OEDN.net is a networked Community of Practice with a membership constituency drawn from cable companies, ITV application vendors, content providers, programming networks, advertisers, academic interactive media researchers and independent consultants. |
https://en.wikipedia.org/wiki/BlyA%20holin%20family | The BlyA Holin Family (TC# 1.E.17) is a group of holin proteins that are approximately 55-70 amino acyl residues (aas) in length and exhibit one transmembrane segment (TMS). A representative list of the proteins belonging to the BlyA holin family can be found in the Transporter Classification Database.
BlyAB
The BlyA membrane protein and the BlyB soluble accessory protein are encoded on the conserved cp32 plasmid of Borrelia burgdorferi, which can be packaged into a bacteriophage particle. These two proteins had previously been proposed to comprise a hemolysis system, but Damman et al. (2000) provided evidence that BlyAB functions as a prophage-encoded holin system. BlyA promotes endolysin-dependent lysis of an induced lambda lysogen that is defective for the lambda holin S gene. The holin pores are generally stable and nonspecific, allowing endolysin access to the peptidoglycan.
Introduction of the Borrelia burgdorferi blyAB locus into Escherichia coli produces a hemolytic phenotype that is dependent on the E. coli clyA (hlyE, sheA) gene (TC# 1.C.10.1.1). Expression of blyA in E. coli causes damage to the E. coli cell envelope and a clyA-dependent hemolytic phenotype, regardless whether blyB is present or absent. The expression of blyB in E. coli, on the other hand, did not have obvious phenotypic effects. Transcriptional studies demonstrated that the clyA gene is not induced in E. coli cells expressing blyA. Furthermore, protein analyses suggested that the impairment of the E. coli cell envelope by BlyA is responsible for the emergence of the hemolytic activity as it allows latent intracellular ClyA protein, derived from basal-level expression of the clyA gene, to leak into the medium and to lyse erythrocytes. These findings are compatible with the presumption that BlyA functions as a membrane-active holin.
Transport Reaction
The physiologically relevant transport reaction believed to be catalyzed by BlyA is:Endolysin (in) → Endolysin (out) |
https://en.wikipedia.org/wiki/Acer%20PICA | The M6100 PICA is a system logic chipset designed by Acer Laboratories introduced in 1993. PICA stands for Performance-enhanced Input-output and CPU Architecture. It was based on the Jazz architecture developed by Microsoft and supported the MIPS Technologies R4000 or R4400 microprocessors. The chipset was designed for computers that run Windows NT, and therefore used ARC firmware to boot Windows NT. The chipset consisted of six chips: a CPU and secondary cache controller, a buffer, a I/O cache and bus controller, a memory controller, and two data buffers.
PICA was used by Acer in its Formula 4000 personal workstation, which NEC sold under the OEM name RISCstation Image. |
https://en.wikipedia.org/wiki/Retrotransposon | Retrotransposons (also called Class I transposable elements or transposons via RNA intermediates) are a type of genetic component that copy and paste themselves into different genomic locations (transposon) by converting RNA back into DNA through the reverse transcription process using an RNA transposition intermediate.
Through reverse transcription, retrotransposons amplify themselves quickly to become abundant in eukaryotic genomes such as maize (49–78%) and humans (42%). They are only present in eukaryotes but share features with retroviruses such as HIV, for example, discontinuous reverse transcriptase-mediated extrachromosomal recombination.
These retrotransposons are regulated by a family of short non-coding RNAs termed as PIWI [P-element induced wimpy testis]-interacting RNAs (piRNAs). piRNA is a recently discovered class of ncRNAs, which are in the length range of ~24-32 nucleotides. Initially, piRNAs were described as repeat-associated siRNAs (rasiRNAs) because of their origin from the repetitive elements such as transposable sequences of the genome. However, later it was identified that they acted via PIWI-protein. In addition to having a role in the suppression of genomic transposons, various roles of piRNAs have been recently reported like regulation of 3’ UTR of protein-coding genes via RNAi, transgenerational epigenetic inheritance to convey a memory of past transposon activity, and RNA-induced epigenetic silencing.
There are two main types of retrotransposons, long terminal repeats (LTRs) and non-long terminal repeats (non-LTRs). Retrotransposons are classified based on sequence and method of transposition. Most retrotransposons in the maize genome are LTR, whereas in humans they are mostly non-LTR. Retrotransposons (mostly of the LTR type) can be passed onto the next generation of a host species through the germline.
The other type of transposon is the DNA transposon. DNA transposons encode a transposase which, when translated, catalyses the exc |
https://en.wikipedia.org/wiki/Spring%20bloom | The spring bloom is a strong increase in phytoplankton abundance (i.e. stock) that typically occurs in the early spring and lasts until late spring or early summer. This seasonal event is characteristic of temperate North Atlantic, sub-polar, and coastal waters. Phytoplankton blooms occur when growth exceeds losses, however there is no universally accepted definition of the magnitude of change or the threshold of abundance that constitutes a bloom. The magnitude, spatial extent and duration of a bloom depends on a variety of abiotic and biotic factors. Abiotic factors include light availability, nutrients, temperature, and physical processes that influence light availability, and biotic factors include grazing, viral lysis, and phytoplankton physiology. The factors that lead to bloom initiation are still actively debated (see Critical depth).
Classical mechanism
In the spring, more light becomes available and stratification of the water column occurs as increasing temperatures warm the surface waters (referred to as thermal stratification). As a result, vertical mixing is inhibited and phytoplankton and nutrients are entrained in the euphotic zone. This creates a comparatively high nutrient and high light environment that allows rapid phytoplankton growth.
Along with thermal stratification, spring blooms can be triggered by salinity stratification due to freshwater input, from sources such as high river runoff. This type of stratification is normally limited to coastal areas and estuaries, including Chesapeake Bay. Freshwater influences primary productivity in two ways. First, because freshwater is less dense, it rests on top of seawater and creates a stratified water column. Second, freshwater often carries nutrients that phytoplankton need to carry out processes, including photosynthesis.
Rapid increases in phytoplankton growth, that typically occur during the spring bloom, arise because phytoplankton can reproduce rapidly under optimal growth conditions (i.e |
https://en.wikipedia.org/wiki/Crease%20pattern | A crease pattern (commonly referred to as a CP) is an origami diagram that consists of all or most of the creases in the final model, rendered into one image. This is useful for diagramming complex and super-complex models, where the model is often not simple enough to diagram efficiently.
The use of crease patterns originated with designers such as Neal Elias, who used them to record how their models were made. This allowed the more prolific designers to keep track of all their models, and soon crease patterns began to be used as a means for communication of ideas between designers. After a few years of this sort of use, designers such as Robert J. Lang, Meguro Toshiyuki, Jun Maekawa and Peter Engel began to design using crease patterns. This allowed them to create with increasing levels of complexity, and the art of origami reached unprecedented levels of realism. Now most higher-level models are accompanied by crease patterns.
Although not intended as a substitute for diagrams, folding from crease patterns is starting to gain in popularity, partly because of the challenge of being able to 'crack' the pattern, and also partly because the crease pattern is often the only resource available to fold a given model, should the designer choose not to produce diagrams. For example, an algorithm for the automatic development of crease patterns for certain polyhedra with discrete rotational symmetry by composing right frusta has been implemented via a CAD program. The program allows users to specify a target polyhedron and generate a crease pattern that folds into it. Still, there are many cases in which designers wish to sequence the steps of their models but lack the means to design clear diagrams. Such origamists occasionally resort to the sequenced crease pattern (SCP) which is a set of crease patterns showing the creases up to each respective fold. The SCP eliminates the need for diagramming programs or artistic ability while maintaining the step-by-step process for |
https://en.wikipedia.org/wiki/Diffusing-wave%20spectroscopy | Diffusing-wave spectroscopy (DWS) is an optical technique derived from dynamic light scattering (DLS) that studies the dynamics of scattered light in the limit of strong multiple scattering. It has been widely used in the past to study colloidal suspensions, emulsions, foams, gels, biological media and other forms of soft matter. If carefully calibrated, DWS allows the quantitative measurement of microscopic motion in a soft material, from which the rheological properties of the complex medium can be extracted via the microrheology approach.
One-speckle diffusing-wave spectroscopy
Laser light is sent to the sample and the outcoming transmitted or backscattered light is detected by an optoelectric sensor. The light intensity detected is the result of the interference of all the optical waves coming from the different light paths.
The signal is analysed by calculating the intensity autocorrelation function called g2.
For the case of non-interacting particles suspended in a (complex) fluid a direct relation between g2-1 and the mean squared displacement of the particles <Δr2> can be established. Let's note P(s) the probability density function (PDF) of the photon path length s. The relation can be written as follows:
with and is the transport mean free path of scattered light.
For simple cell geometries, it is thus possible to calculate the mean squared displacement of the particles <Δr2> from the measured g2-1 values analytically. For example, for the backscattering geometry, an infinitely thick cell, large laser spot illumination and detection of photons coming from the center of the spot, the relationship between g2-1 and <Δr2> is:
, γ value is around 2.
For less thick cells and in transmission, the relationship depends also on l* (the transport length).
For quasi-transparent cells, an angle-independent variant method called Cavity Amplified Scattering Spectroscopy makes use of an integrating sphere to isotropically probe samples from all directions, elo |
https://en.wikipedia.org/wiki/List%20of%20cholesterol%20in%20foods | This list consists of common foods with their cholesterol content recorded in milligrams per 100 grams (3.5 ounces) of food.
Functions
Cholesterol is a sterol, a steroid-like lipid made by animals, including humans. The human body makes one-eighth to one-fourth teaspoons of pure cholesterol daily. A cholesterol level of 5.5 millimoles per litre or below is recommended for an adult. The rise of cholesterol in the body can give a condition in which excessive cholesterol is deposited in artery walls called atherosclerosis. This condition blocks the blood flow to vital organs which can result in high blood pressure or stroke.
Cholesterol is not always bad. It's a vital part of the cell wall and a precursor to substances such as brain matter and some sex hormones. There are some types of cholesterol which are beneficial to the heart and blood vessels. High-density lipoprotein is commonly called "good" cholesterol. These lipoproteins help in the removal of cholesterol from the cells, which is then transported back to the liver where it is disintegrated and excreted as waste or broken down into parts.
Cholesterol content of various foods
See also
Nutrition
Plant stanol ester
Fatty acid |
https://en.wikipedia.org/wiki/Clinical%20biologist | A clinical biologist is a health professional such as a doctor of medicine, pharmacist, chemist or biologist that is specialized in clinical biology, a medical specialty derived from clinical pathology. The concept includes interventional biology, including assisted reproductive technology.
These professionals follow a medical residency whose duration varies between countries (from 3 to 5 years).
This term is frequently used in France, Belgium and other countries in Western Europe, Africa or Asia.
See also
Biological pharmacist
Medical laboratory
Clinical laboratory scientist
Clinical pathology
Pathology |
https://en.wikipedia.org/wiki/616%20%28number%29 | 616 (six hundred [and] sixteen) is the natural number following 615 and preceding 617.
While 666 is called the "number of the beast" in most manuscripts of Revelation , a fragment of the earliest papyrus 115 gives the number as 616.
In mathematics
616 is a member of the Padovan sequence, coming after 265, 351, 465 (it is the sum of the first two of these). 616 is a polygonal number in four different ways: it is a heptagonal number, as well as 13-, 31- and 104-gonal.
It is also the sum of the squares of the factorials of 2,3,4: (2!)² + (3!)² + (4!)² = 4+36+576=616.
The 616th harmonic number is the first to exceed seven.
Number of the beast
666 is generally believed to have been the original Number of the Beast in the Book of Revelation in the Christian Bible. In 2005, however, a fragment of papyrus 115 was revealed, containing the earliest known version of that part of the Book of Revelation discussing the Number of the Beast. It gave the number as 616, suggesting that this may have been the original. One possible explanation for the two different numbers is that they reflect two different spellings of Emperor Nero/Neron's name, for which (according to this theory) this number is believed to be a code.
In other fields
Earth-616 is the name used to identify the primary continuity in which most Marvel Comics' titles take place.
616 film, a medium film format.
Area code 616, an area code in Michigan. |
https://en.wikipedia.org/wiki/Intracellular%20antibody-mediated%20degradation | Intracellular antibody-mediated degradation (IAMD) is a neutralization mechanism of intracellular antibody-mediated immunity whereby an effector protein, TRIM21, directs antibody bound virions to the proteasome where they are degraded. As yet, it has only been observed to act against the adenovirus but is likely to also be effective against other non-enveloped viruses.
Mechanism of action
In IAMD, the neutralization of the pathogen follows a non-cytotoxic mechanism. That is, the infected cell is not attacked as in Antibody-dependent cell-mediated cytotoxicity, instead the virions are rapidly destroyed and the cell may be relieved of infection.
Immunoglobulin G (IgG) binds specifically to the target antigen presented on the pathogen extracellularly
The antibody bound pathogen infects a host cell
In the cytosol, TRIM21 (a protein of the Tripartite motif family) binds with high affinity to IgG
TRIM21 is conjugated with ubiquitin, which directs the complex to the proteasome
Degradation by proteolysis of both the protein capsid and the antibody occurs, but not the TRIM21 protein
Resistance to mutants
There are a number of reasons why IAMD is so resistant to evasion by mutants through evolution:
The targeting of pathogens by antibodies is adaptive while the degradation is innate; the overall response therefore combines both adaptive and innate immunity.
The proteasomal targeting is mediated by the autoubiquitination of TRIM21, there is no direct interaction with the pathogen so mutants which evade ubiquitination themselves cannot evade IAMD.
Unlike extracellular humoral immune responses, this intracellular mechanism is expressed in most human tissues and is an example of encapsulating immunity as opposed to mere immune surveillance.
See also
Proteasomal pathway |
https://en.wikipedia.org/wiki/Fields%20Medal%20Symposium | The Fields Medal Symposium is an annual event that honours one of the Fields Medal recipients from the most recent International Congress of Mathematicians. The symposium is jointly endorsed by the International Mathematical Union and the Fields Institute for Mathematical Sciences. The idea was conceived in preparation for the International Congress of Mathematicians 2010 (ICM2010) in Hyberdad, India. Professor Edward Bierstone of the University of Toronto was the director of the institute during the inaugural symposium in October 2012. All symposiums take place at the Fields Institute in Toronto, Canada. The symposia include mathematical activity that explore work related to the honoured Fields Medallist. They will include public lectures meant to spark interest in mathematics including public lectures and events for students.
List of Symposium Honorees |
https://en.wikipedia.org/wiki/Titan%20submersible%20implosion | On 18 June 2023, Titan, a submersible operated by American tourism and expeditions company OceanGate, imploded during an expedition to view the wreck of Titanic in the North Atlantic Ocean off the coast of Newfoundland, Canada. On board the submersible were Stockton Rush, the American CEO of OceanGate; Paul-Henri Nargeolet, a French deep-sea explorer and Titanic expert; Hamish Harding, a British businessman; Shahzada Dawood, a Pakistani-British businessman; and Dawood's son Suleman.
Communication between Titan and its mother ship, Polar Prince, was lost 1 hour 45 minutes into the dive. Authorities were alerted when it failed to resurface at the scheduled time later that day. After the submersible had been missing for four days, a remotely operated underwater vehicle (ROV) discovered a debris field containing parts of Titan, about from the bow of Titanic. The search area was informed by the United States Navy's (USN) sonar detection of an acoustic signature consistent with an implosion around the time communications with the submersible ceased, suggesting the pressure hull had imploded while Titan was descending, resulting in the instantaneous deaths of all five occupants.
The search and rescue operation was conducted by an international team led by the United States Coast Guard (USCG), USN, and Canadian Coast Guard. Support was provided by aircraft from the Royal Canadian Air Force and United States Air National Guard, a Royal Canadian Navy ship, as well as several commercial and research vessels and ROVs.
Numerous industry experts had raised concerns about the safety of the vessel. OceanGate executives, including Rush, had not sought certification for Titan, arguing that excessive safety protocols and regulations hindered innovation.
Background
OceanGate
OceanGate is a private company, founded in 2009 by Stockton Rush and Guillermo Söhnlein. From 2010 until the loss of the Titan submersible, OceanGate transported paying customers in leased commercial submer |
https://en.wikipedia.org/wiki/Comparison%20of%20machine%20translation%20applications | Machine translation is an algorithm which attempts to translate text or speech from one natural language to another.
General information
Basic general information for popular machine translation applications.
Languages features comparison
The following table compares the number of languages which the following machine translation programs can translate between.
(Moses and Moses for Mere Mortals allow you to train translation models for any language pair, though collections of translated texts (parallel corpus) need to be provided by the user. The Moses site provides links to training corpora.)
This is not an all-encompassing list. Some applications have many more language pairs than those listed below. This is a general comparison of key languages only. A full and accurate list of language pairs supported by each product should be found on each of the product's websites.
See also
Machine translation
Machine translation software usability
Computer-assisted translation
Comparison of computer-assisted translation tools
External links
Apertium wiki (list of language pairs and licence information)
Xerox Easy Translator Service (list of language pairs)
Bing Translator Language List
Haitian Creole support in Bing/Microsoft Translator
Microsoft Research: Syntactically Informed Phrasal SMT
List of supported languages in Google Translate |
https://en.wikipedia.org/wiki/Orthodox%20seed | Orthodox seeds are seeds which will survive drying and/or freezing during ex-situ conservation, as opposed to recalcitrant seeds, which will not. According to information from the U.S. Department of Agriculture, there is variation in the ability of orthodox seeds to withstand drying and storage, with some seeds being more sensitive than others. Thus some seeds are considered intermediate in their storage capability while others are fully orthodox. One notable example of a long-lived orthodox seed which survived accidental storage followed by controlled germination is the case of the 2,000-year-old Judean date palm (cultivar of Phoenix dactylifera) seed which successfully sprouted in 2005. This particular seed is reputed to be the oldest viable seed, but the upper survival time limit of properly stored seeds remains unknown.
See also
Micropropagation
Plant propagation
Seedbank
Notes
External links
Woody Plant Seed Manual - USDA FS Agriculture Handbook 727
How long can a seed remain alive?
Plant reproduction
Seeds |
https://en.wikipedia.org/wiki/Onsager%E2%80%93Machlup%20function | The Onsager–Machlup function is a function that summarizes the dynamics of a continuous stochastic process. It is used to define a probability density for a stochastic process, and it is similar to the Lagrangian of a dynamical system. It is named after Lars Onsager and who were the first to consider such probability densities.
The dynamics of a continuous stochastic process from time to in one dimension, satisfying a stochastic differential equation
where is a Wiener process, can in approximation be described by the probability density function of its value at a finite number of points in time :
where
and , and . A similar approximation is possible for processes in higher dimensions. The approximation is more accurate for smaller time step sizes , but in the limit the probability density function becomes ill defined, one reason being that the product of terms
diverges to infinity. In order to nevertheless define a density for the continuous stochastic process , ratios of probabilities of lying within a small distance from smooth curves and are considered:
as , where is the Onsager–Machlup function.
Definition
Consider a -dimensional Riemannian manifold and a diffusion process on with infinitesimal generator , where is the Laplace–Beltrami operator and is a vector field. For any two smooth curves ,
where is the Riemannian distance, denote the first derivatives of , and is called the Onsager–Machlup function.
The Onsager–Machlup function is given by
where is the Riemannian norm in the tangent space at , is the divergence of at , and is the scalar curvature at .
Examples
The following examples give explicit expressions for the Onsager–Machlup function of a continuous stochastic processes.
Wiener process on the real line
The Onsager–Machlup function of a Wiener process on the real line is given by
Proof: Let be a Wiener process on and let be a twice differentiable curve such that . Define another process by and a measure by |
https://en.wikipedia.org/wiki/Quantization%20%28signal%20processing%29 | Quantization, in mathematics and digital signal processing, is the process of mapping input values from a large set (often a continuous set) to output values in a (countable) smaller set, often with a finite number of elements. Rounding and truncation are typical examples of quantization processes. Quantization is involved to some degree in nearly all digital signal processing, as the process of representing a signal in digital form ordinarily involves rounding. Quantization also forms the core of essentially all lossy compression algorithms.
The difference between an input value and its quantized value (such as round-off error) is referred to as quantization error. A device or algorithmic function that performs quantization is called a quantizer. An analog-to-digital converter is an example of a quantizer.
Example
For example, rounding a real number to the nearest integer value forms a very basic type of quantizer – a uniform one. A typical (mid-tread) uniform quantizer with a quantization step size equal to some value can be expressed as
,
where the notation denotes the floor function.
Alternatively, the same quantizer may be expressed in terms of the ceiling function, as
.
(The notation denotes the ceiling function).
The essential property of a quantizer is having a countable-set of possible output-values members smaller than the set of possible input values. The members of the set of output values may have integer, rational, or real values. For simple rounding to the nearest integer, the step size is equal to 1. With or with equal to any other integer value, this quantizer has real-valued inputs and integer-valued outputs.
When the quantization step size (Δ) is small relative to the variation in the signal being quantized, it is relatively simple to show that the mean squared error produced by such a rounding operation will be approximately . Mean squared error is also called the quantization noise power. Adding one bit to the quantizer ha |
https://en.wikipedia.org/wiki/Pseudo-zero%20set | In complex analysis (a branch of mathematical analysis), the pseudo-zero set or root neighborhood of a degree-m polynomial p(z) is the set of all complex numbers that are roots of polynomials whose coefficients differ from those of p by a small amount. Namely, given a norm on the space of polynomial coefficients, the pseudo-zero set is the set of all zeros of all degree-m polynomials q such that (as vectors of coefficients) is less than a given ε.
See also
List of complex analysis topics
Timeline of calculus and mathematical analysis |
https://en.wikipedia.org/wiki/CPC%20Binary%20Barcode | CPC Binary Barcode is Canada Post's proprietary symbology used in its automated mail sortation operations. This barcode is used on regular-size pieces of mail, especially mail sent using Canada Post's Lettermail service. This barcode is printed on the lower-right-hand corner of each faced envelope, using a unique ultraviolet-fluorescent ink.
Symbology description
The applied barcode uses printed and non-printed bars spaced 3 mm apart, and consists of two fields. The rightmost field, which is 27 bars in width, encodes the destination postal code. The leftmost field is 9 bars in width and applied right below the printed destination address. It is currently unclear what this field is used for.
In the postal code field, the rightmost bar is always printed, to allow the sortation equipment to properly lock onto the barcode and scan it. The leftmost bar, a parity field, is printed only when necessary to give the postal code field an odd number of printed bars. The remaining 25 bars represent the actual destination postal code. To eliminate any possibility of ambiguity during the scanning process, run-length restrictions are used within the postal code field. No more than five consecutive non-printed bars, or spaces, are permitted, and no more than six consecutive printed bars are allowed.
The actual representation of the postal code is split into four subfields of the barcode, each with their own separate encoding table. The first and last subfields, which share a common encoding table, are always eight bars in width, and encode the first two characters and the last two characters of the postal code respectively. The second subfield, which encodes the third character of the postal code, is always five bars in width, and the third subfield, which encodes the fourth character, is always four bars wide.
Generating barcodes
Disregarding the space, divide the postal code into four subfields (e.g. K1-A-0-B1).
Locate the contents of each subfield in the encoding t |
https://en.wikipedia.org/wiki/Hylogenesis | Hylogenesis is a physical theory about the mechanism behind the origins of dark matter and antimatter. It was proposed in August 2010 in a paper by Hooman Davoudiasl, David E. Morrissey, Kris Sigurdson and Sean Tulin.
The theory involves a fermion X, and its antiparticle , both of which may couple into quarks in the visible sector, and into hidden particles in a hidden sector, a sector which is not part of the Standard Model. The hidden states have masses near a GeV and very weak couplings to particles in the Standard Model. X and respectively decay into either baryonic matter or hidden baryonic matter, and into either antibaryonic matter or hidden antibaryonic matter, violating CP and quark baryon number.
An excess of baryonic matter is created in the visible sector, and an excess of antimatter is created in the hidden sector. The hidden antimatter is explained as being stable dark matter. The X and particles have a conserved baryon number charge, so equal and opposite charges appear in the visible and hidden sectors. Therefore, the Universe's total baryon charge stays zero.
See also
Baryogenesis |
https://en.wikipedia.org/wiki/Cross-recurrence%20quantification | Cross-recurrence quantification (CRQ) is a non-linear method that quantifies how similarly two observed data series unfold over time. CRQ produces measures reflecting coordination, such as how often two data series have similar values or reflect similar system states (called percentage recurrence, or %REC), among other measures. |
https://en.wikipedia.org/wiki/WUPL | WUPL (channel 54) is a television station licensed to Slidell, Louisiana, United States, serving the New Orleans area as an affiliate of MyNetworkTV. It is owned by Tegna Inc. alongside CBS affiliate WWL-TV (channel 4). Both stations share studios on Rampart Street in the historic French Quarter district, while WUPL's transmitter is located on Cooper Road in Terrytown, Louisiana.
History
As a UPN affiliate
The station first signed on the air on June 1, 1995, as an affiliate of the United Paramount Network (UPN). It was owned by Texas broadcaster Larry Safir via his company, Middle America Communications. Safir also owned Univision affiliate KNVO in the Rio Grande Valley. Prior to the station's sign-on, WHNO (channel 20) was approached by UPN for an affiliation, though WHNO's owner LeSEA Broadcasting declined all netlet offers on their stations through the country, as the programming planned for both UPN and competitor The WB conflicted with the company's core programming values; as a result, programming from UPN, which launched on January 16, 1995, was only available on New Orleans-area cable and satellite providers through New York City-based national superstation WWOR for the 5½ months prior to WUPL's debut. Along with programming from UPN, the station ran a general entertainment format, offering vintage off-network sitcoms, talk shows, court shows and other syndicated programs. In 1996, Safir entered a deal with Cox Enterprises to take over operations of the station, and in 1997, he sold the station to the Paramount Stations Group subsidiary of Viacom; as a result, WUPL became a UPN owned-and-operated station (Viacom launched UPN in a programming partnership with Chris-Craft Industries/United Television, and acquired a 50% interest in the network from Chris-Craft/United in 1996).
Viacom merged with CBS in 2000. Despite Viacom's ownership of WUPL, the market's CBS affiliation remained on WWL-TV (channel 4), the highest-rated television station in New Orleans an |
https://en.wikipedia.org/wiki/Moreau%20envelope | The Moreau envelope (or the Moreau-Yosida regularization) of a proper lower semi-continuous convex function is a smoothed version of . It was proposed by Jean-Jacques Moreau in 1965.
The Moreau envelope has important applications in mathematical optimization: minimizing over and minimizing over are equivalent problems in the sense that set of minimizers of and are the same. However, first-order optimization algorithms can be directly applied to , since may be non-differentiable while is always continuously differentiable. Indeed, many proximal gradient methods can be interpreted as a gradient descent method over .
Definition
The Moreau envelope of a proper lower semi-continuous convex function from a Hilbert space to is defined as
Given a parameter , the Moreau envelope of is also called as the Moreau envelope of with parameter .
Properties
The Moreau envelope can also be seen as the infimal convolution between and .
The proximal operator of a function is related to the gradient of the Moreau envelope by the following identity:
. By defining the sequence and using the above identity, we can interpret the proximal operator as a gradient descent algorithm over the Moreau envelope.
Using Fenchel's duality theorem, one can derive the following dual formulation of the Moreau envelope:
where denotes the convex conjugate of .
Since the subdifferential of a proper, convex, lower semicontinuous function on a Hilbert space is inverse to the subdifferential of its convex conjugate, we can conclude that if is the maximizer of the above expression, then is the minimizer in the primal formulation and vice versa.
By Hopf-Lax formula, the Moreau envelope is a viscosity solution to a Hamilton-Jacobi equation. Stanley Osher and co-authors used this property and Cole-Hopf transformation to derive an algorithm to compute approximations to the proximal operator of a function.
See also
Proximal operator
Proximal gradient method |
https://en.wikipedia.org/wiki/Nimber | In mathematics, the nimbers, also called Grundy numbers, are introduced in combinatorial game theory, where they are defined as the values of heaps in the game Nim. The nimbers are the ordinal numbers endowed with nimber addition and nimber multiplication, which are distinct from ordinal addition and ordinal multiplication.
Because of the Sprague–Grundy theorem which states that every impartial game is equivalent to a Nim heap of a certain size, nimbers arise in a much larger class of impartial games. They may also occur in partisan games like Domineering.
The nimber addition and multiplication operations are associative and commutative. Each nimber is its own additive inverse. In particular for some pairs of ordinals, their nimber sum is smaller than either addend. The minimum excludant operation is applied to sets of nimbers.
Uses
Nim
Nim is a game in which two players take turns removing objects from distinct heaps. As moves depend only on the position and not on which of the two players is currently moving, and where the payoffs are symmetric, Nim is an impartial game. On each turn, a player must remove at least one object, and may remove any number of objects provided they all come from the same heap. The goal of the game is to be the player who removes the last object. The nimber of a heap is simply the number of objects in that heap. Using nim addition, one can calculate the nimber of the game as a whole. The winning strategy is to force the nimber of the game to 0 for the opponent's turn.
Cram
Cram is a game often played on a rectangular board in which players take turns placing dominoes either horizontally or vertically until no more dominoes can be placed. The first player that cannot make a move loses. As the possible moves for both players are the same, it is an impartial game and can have a nimber value. For example, any board that is an even size by an even size will have a nimber of 0. Any board that is even by odd will have a non-zero ni |
https://en.wikipedia.org/wiki/Anisogamy | Anisogamy is a form of sexual reproduction that involves the union or fusion of two gametes that differ in size and/or form. The smaller gamete is male, a sperm cell, whereas the larger gamete is female, typically an egg cell. Anisogamy is predominant among multicellular organisms. In both plants and animals gamete size difference is the fundamental difference between females and males.
Anisogamy most likely evolved from isogamy. Since the biological definition of male and female is based on gamete size, the evolution of anisogamy is viewed as the evolutionary origin of male and female sexes. Anisogamy is an outcome of
both natural selection and sexual selection, and led the sexes to different primary and secondary sex characteristics including sex differences in behavior.
Geoff Parker, Robin Baker, and Vic Smith were the first to provide a mathematical model for the evolution of anisogamy that was consistent with modern evolutionary theory. Their theory was widely accepted but there are alternative hypotheses about the evolution of anisogamy.
Etymology
Anisogamy comes from the ancient Greek words 'aniso' meaning unequal and 'gamy' meaning marriage. The first known use of the term anisogamy was in the year 1891.
Definition
Anisogamy is the form of sexual reproduction that involves the union or fusion of two gametes which differ in size and/or form. The smaller gamete is considered to be male (a sperm cell), whereas the larger gamete is regarded as female (typically an egg cell, if non-motile).
There are several types of anisogamy. Both gametes may be flagellated and therefore motile. Alternatively, as in flowering plants, conifers and gnetophytes, neither of the gametes are flagellated. In these groups, the male gametes are non-motile cells within pollen grains, and are delivered to the egg cells by means of pollen tubes. In the red alga Polysiphonia, non-motile eggs are fertilized by non-motile sperm.
The form of anisogamy that occurs in animals, includ |
https://en.wikipedia.org/wiki/Contact%20%28novel%29 | Contact is a 1985 hard science fiction novel by American scientist Carl Sagan. It deals with the theme of contact between humanity and a more technologically advanced, extraterrestrial life form. It ranked No. 7 on the 1985 U.S. bestseller list. The only full work of fiction published by Sagan, the novel originated as a screenplay by Sagan and Ann Druyan (whom he later married) in 1979; when development of the film stalled, Sagan decided to convert the stalled film into a novel. The film concept was subsequently revived and eventually released in 1997 as the film Contact starring Jodie Foster.
Plot
The Message
As a child, Eleanor "Ellie" Arroway displays a strong aptitude for science and mathematics. Dissatisfied with a school lesson, she goes to the library to convince herself that pi is transcendental. In sixth grade, her father Theodore ("Ted") dies. John Staughton, her new stepfather, does not show as much support for her interests. Ellie refuses to accept him as a family member and believes her mother only remarried out of weakness.
After graduating from Harvard University, Ellie receives a doctorate from Caltech supervised by David Drumlin, a well-known radio astronomer. She becomes the director of "Project Argus", a radio telescope array in New Mexico dedicated to the search for extraterrestrial intelligence (SETI). This puts her at odds with most of the scientific community, including Drumlin, who tries to have the funding to SETI cut off. The project eventually discovers a signal containing a series of prime numbers coming from the Vega system, 26 light years away. Further analysis reveals information in the polarization modulation of the signal: a retransmission of Adolf Hitler's opening speech at the 1936 Summer Olympics in Berlin, the first television signal powerful enough to escape Earth's ionosphere.
The President of the United States meets with Ellie to discuss the implications of the first confirmed communication from extraterrestrial beings. El |
https://en.wikipedia.org/wiki/Protomap%20%28neuroscience%29 | The Protomap is a primordial molecular map of the functional areas of the mammalian cerebral cortex during early embryonic development, at a stage when neural stem cells are still the dominant cell type. The protomap is a feature of the ventricular zone, which contains the principal cortical progenitor cells, known as radial glial cells. Through a process called 'cortical patterning', the protomap is patterned by a system of signaling centers in the embryo, which provide positional information and cell fate instructions. These early genetic instructions set in motion a development and maturation process that gives rise to the mature functional areas of the cortex, for example the visual, somatosensory, and motor areas.
The term protomap was coined by Pasko Rakic. The protomap hypothesis was opposed by the protocortex hypothesis, which proposes that cortical proto-areas initially have the same potential, and that regionalization in large part is controlled by external influences, such as axonal inputs from the thalamus to the cortex. However, a series of papers in the year 2000 and in 2001 provided strong evidence against the protocortex hypothesis, and the protomap hypothesis has been well accepted since then. The protomap hypothesis, together with the related radial unit hypothesis, forms our core understanding of the embryonic development of the cerebral cortex. Once the basic structure is present and cortical neurons have migrated to their final destinations, many other processes contribute to the maturation of functional cortical circuits.
See also
Radial unit hypothesis
Neural stem cell
Stem cell
Neurogenesis
Cellular differentiation
Cortical patterning
Gyrification |
https://en.wikipedia.org/wiki/Esenin-Volpin%27s%20theorem | In mathematics, Esenin-Volpin's theorem states that weight of an infinite compact dyadic space is the supremum of the weights of its points.
It was introduced by . It was generalized by and . |
https://en.wikipedia.org/wiki/Modulus%20of%20convergence | In real analysis, a branch of mathematics, a modulus of convergence is a function that tells how quickly a convergent sequence converges. These moduli are often employed in the study of computable analysis and constructive mathematics.
If a sequence of real numbers converges to a real number , then by definition, for every real there is a natural number such that if then . A modulus of convergence is essentially a function that, given , returns a corresponding value of .
Definition
Suppose that is a convergent sequence of real numbers with limit . There are two ways of defining a modulus of convergence as a function from natural numbers to natural numbers:
As a function such that for all , if then .
As a function such that for all , if then .
The latter definition is often employed in constructive settings, where the limit may actually be identified with the convergent sequence. Some authors use an alternate definition that replaces with .
See also
Modulus of continuity |
https://en.wikipedia.org/wiki/Lancelot%20Hogben | Lancelot Thomas Hogben FRS FRSE (9 December 1895 – 22 August 1975) was a British experimental zoologist and medical statistician. He developed the African clawed frog (Xenopus laevis) as a model organism for biological research in his early career, attacked the eugenics movement in the middle of his career, and wrote popular books on science, mathematics and language in his later career.
Early life and education
Hogben was born and raised in Southsea near Portsmouth in Hampshire. His parents were Methodists. He attended Tottenham County School in London, his family having moved to Stoke Newington, where his mother had grown up, in 1907, and then as a medical student studied physiology at Trinity College, Cambridge. Hogben had matriculated into the University of London as an external student before he could apply to Cambridge and he graduated as a Bachelor of Science (BSc) in 1914. He took his Cambridge degree in 1915, graduating with an Ordinary BA. He had acquired socialist convictions, changing the name of the university's Fabian Society to Socialist Society and went on to become an active member of the Independent Labour Party. Later in life he preferred to describe himself as 'a scientific humanist'.
In the First World War he was a pacifist, and joined the Quakers. He worked for six months with the Red Cross in France, under the auspices of the Friends' War Victims Relief Service and then the Friends' Ambulance Unit. He then returned to Cambridge, and was imprisoned in Wormwood Scrubs as a conscientious objector in 1916. His health collapsed and he was released in 1917. His brother George was also a conscientious objector, serving with the Friends' Ambulance Unit.
Career
After a year's convalescence he took lecturing positions in London universities and in 1921 he became a Doctor of Science (D.Sc.) in Zoology of the University of London. He moved in 1922 to the University of Edinburgh and its Animal Breeding Research Department.In 1923, Hogben was a founder |
https://en.wikipedia.org/wiki/Charles%20Parsons%20%28philosopher%29 | Charles Dacre Parsons (born April 13, 1933) is an American philosopher best known for his work in the philosophy of mathematics and the study of the philosophy of Immanuel Kant. He is professor emeritus at Harvard University.
Life and career
Parsons is a son of the famous Harvard sociologist Talcott Parsons. He earned his Ph.D. in philosophy at Harvard University in 1961, under the direction of Burton Dreben and Willard Van Orman Quine. He taught for many years at Columbia University before moving to Harvard University in 1989. He retired in 2005 as the Edgar Pierce professor of philosophy, a position formerly held by Quine.
He is an elected Fellow of the American Academy of Arts and Sciences and the Norwegian Academy of Science and Letters.
Among his former doctoral students are Michael Levin, James Higginbotham, Peter Ludlow, Gila Sher, Øystein Linnebo, Richard Tieszen, and Mark van Atten.
In 2017, Parsons held the Gödel Lecture titled Gödel and the universe of sets.
Philosophical work
In addition to his work in logic and the philosophy of mathematics, Parsons was an editor, with Solomon Feferman and others, of the posthumous works of Kurt Gödel. He has also written on historical figures, especially Immanuel Kant, Gottlob Frege, Kurt Gödel, and Willard Van Orman Quine.
Works
Books
1983. Mathematics in Philosophy: Selected Essays. Ithaca, N.Y.: Cornell Univ. Press.
2008. Mathematical Thought and its Objects. Cambridge Univ. Press.
2012. From Kant to Husserl: Selected Essays. Cambridge, Massachusetts, and London: Harvard Univ. Press.
2014a. Philosophy of Mathematics in the Twentieth Century: Selected Essays. Cambridge, Massachusetts, and London: Harvard Univ. Press.
Selected articles
1987. "Developing Arithmetic in Set Theory without infinity: Some Historical Remarks". History and Philosophy of Logic, vol. 8, pp. 201–213.
1990a. "The Uniqueness of the Natural Numbers". Iyyun, vol. 39, pp. 13–44. ISSN 0021-3306.
1990b. "The Structuralist |
https://en.wikipedia.org/wiki/Hodgkin%20lymphoma | Hodgkin lymphoma (HL) is a type of lymphoma in which cancer originates from a specific type of white blood cell called lymphocytes, where multinucleated Reed–Sternberg cells (RS cells) are present in the patient's lymph nodes. The condition was named after the English physician Thomas Hodgkin, who first described it in 1832. Symptoms may include fever, night sweats, and weight loss. Often, nonpainful enlarged lymph nodes occur in the neck, under the arm, or in the groin. Those affected may feel tired or be itchy.
The two major types of Hodgkin lymphoma are classic Hodgkin lymphoma and nodular lymphocyte-predominant Hodgkin lymphoma. About half of cases of Hodgkin lymphoma are due to Epstein–Barr virus (EBV) and these are generally the classic form. Other risk factors include a family history of the condition and having HIV/AIDS. Diagnosis is conducted by confirming the presence of cancer and identifying RS cells in lymph node biopsies. The virus-positive cases are classified as a form of the Epstein–Barr virus-associated lymphoproliferative diseases.
Hodgkin lymphoma may be treated with chemotherapy, radiation therapy, and stem-cell transplantation. The choice of treatment often depends on how advanced the cancer has become and whether or not it has favorable features. If the disease is detected early, a cure is often possible. In the United States, 88% of people diagnosed with Hodgkin lymphoma survive for five years or longer. For those under the age of 20, rates of survival are 97%. Radiation and some chemotherapy drugs, however, increase the risk of other cancers, heart disease, or lung disease over the subsequent decades.
In 2015, about 574,000 people globally had Hodgkin lymphoma, and 23,900 (4.2%) died. In the United States, 0.2% of people are affected at some point in their life. Most people are diagnosed with the disease between the ages of 20 and 40.
Signs and symptoms
People with Hodgkin lymphoma may present with these symptoms:
Lymphadenopathy: The m |
https://en.wikipedia.org/wiki/Group%20of%20pictures | In video coding, a group of pictures, or GOP structure, specifies the order in which intra- and inter-frames are arranged. The GOP is a collection of successive pictures within a coded video stream. Each coded video stream consists of successive GOPs, from which the visible frames are generated. Encountering a new GOP in a compressed video stream means that the decoder doesn't need any previous frames in order to decode the next ones, and allows fast seeking through the video.
Description
A GOP can contain the following picture types:
I picture or I frame (intra coded picture, also called keyframe or i-frame) – a picture that is coded independently of all other pictures. Each GOP begins (in decoding order) with this type of picture.
P picture or P frame (predictive coded picture) – contains motion-compensated difference information relative to previously decoded pictures. In older designs such as MPEG-1, H.262/MPEG-2 and H.263, each P picture can only reference one picture, and that picture must precede the P picture in display order as well as in decoding order and must be an I or P picture. These constraints do not apply in the newer standards H.264/MPEG-4 AVC and HEVC.
B picture or B frame (bipredictive coded picture) – contains motion-compensated difference information relative to previously decoded pictures. In older designs such as MPEG-1 and H.262/MPEG-2, each B picture can only reference two pictures, the one which precedes the B picture in display order and the one which follows, and all referenced pictures must be I or P pictures. These constraints do not apply in newer standards H.264/MPEG-4 AVC and HEVC.
D picture or D frame (DC direct coded picture) – serves as a fast-access representation of a picture for loss robustness or fast-forward. D pictures are only used in MPEG-1 video.
An I frame indicates the beginning of a GOP. Afterwards several P and B frames follow. In older designs, the allowed ordering and referencing structure is relatively con |
https://en.wikipedia.org/wiki/Virtuous%20Pedophiles | Virtuous Pedophiles is an Internet-based mutual support group and public awareness group for people with various chronophilias who acknowledge having a primary or partial romantic and/or sexual attraction to minors but want to lead normal productive lives without having to engage in sexual acts with them. The main goal of the group is to help the public become more aware of the existence of virtuous people with attractions like them. The two founders of the group use the pseudonyms Ethan Edwards and Nick Devin. They do not reveal their true identity for their safety.
Recognition
The group's efforts have been discussed by human sexuality experts, such as Jesse Bering.
In 2017, Alexander McBride of Vice News wrote: "many of these claims [of not offending] cannot be verified. Perhaps some are using VirPed as a cover-up; perhaps some, who were even more daring, saw my photo story as a way to prove they had nothing to hide. I cannot guarantee that this is not the case and I can understand why many would be suspicious."
See also
Prevention Project Dunkelfeld – German clinical support service for individuals who are attracted to minors
Circles of Support and Accountability – Professionally supervised volunteer groups which support offenders with societal reintegration post incarceration.
Association for the Treatment and Prevention of Sexual Abuse |
https://en.wikipedia.org/wiki/Cryofibrinogenemia | Cryofibrinogenemia refers to a condition classified as a fibrinogen disorder in which a person's blood plasma is allowed to cool substantially (i.e. from its normal temperature of 37 °C to the near-freezing temperature of 4 °C), causing the (reversible) precipitation of a complex containing fibrinogen, fibrin, fibronectin, and, occasionally, small amounts of fibrin split products, albumin, immunoglobulins and other plasma proteins.
Return of plasma to more normal temperature resolubilizes the precipitate.
Cryofibrinogenemia may occur in individuals that have no obvious evidence of precipitate-induced tissue damage (asymptomatic cryofibrinogenemia), or in consequence of cryofibrinogen precipitation resulting in blood clots in small and medium size arteries and veins.
When occurring in association with another causal disease, cryofibrinogenemic disease is referred as secondary cryofibrinogenemia; in the absence of such an association, it is referred to as primary cryofibrinogenemia.
Cryofibrinogen precipitation
The reasons for the cold temperature-induced in vitro as well as the in vivo precipitation of the fibrinogen-containing complex is unknown. The fibrinogen involved in precipitate formation appears to have a normal structure. This separates cryofibrinogenemia from two pathological blood-clotting/bleeding diseases that can mimic cryofibrinogenemia but are due to structurally abnormal fibrinogen viz., dysfibrinogenemia and hypodysfibrinogenemia. Based on in vitro studies, three causes have been hypothesized for the precipitate formed in cryofibrinogenemia. 1) The blood and plasma of individuals with cryofibrinogenemia lack the fibrinolysis activity that normally degrades and thereby resolubilizes the precipitate. This hypothesis is based on the findings that some but not all individuals with the disorder have abnormally high levels of one or two of the agents, alpha-1 antitrypsin and alpha-2-Macroglobulin, which inhibit the naturally occurring fibrinolytic age |
https://en.wikipedia.org/wiki/Beno%20Arbel | Been Arbel (; 20 January 1939 – 9 April 2013) was an Israeli mathematician and historian of mathematics who worked as Professor of Mathematics at Tel Aviv University.
Biography
Born in Drăgănești-Olt, Romania, Arbel began his academic studies at the University of Bucharest, which he continued at the Hebrew University of Jerusalem upon immigrating to Israel in 1961. He completed his baccalaureate in mathematics and physics there in 1963, and his master's degree in mathematics in April 1965 (under the supervision of Aryeh Dvoretzky), a month after which he enlisted in the Israel Defense Forces. Arbel received his Ph.D. in 1987 from the Hebrew University under Marcel Herzog, and went on to teach at Tel Aviv University, Kibbutzim College, Beit Berl Academic College, and the .
From the late 1980s, Arbel served as director of the program for gifted young students in mathematics and computer science at Tel Aviv University.
Selected works |
https://en.wikipedia.org/wiki/Broadcasting%20%28networking%29 | In computer networking, telecommunication and information theory, broadcasting is a method of transferring a message to all recipients simultaneously. Broadcasting can be performed as a high-level operation in a program, for example, broadcasting in Message Passing Interface, or it may be a low-level networking operation, for example broadcasting on Ethernet.
All-to-all communication is a computer communication method in which each sender transmits messages to all receivers within a group. In networking this can be accomplished using broadcast or multicast. This is in contrast with the point-to-point method in which each sender communicates with one receiver.
Addressing methods
There are four principal addressing methods in the Internet Protocol:
Overview
In computer networking, broadcasting refers to transmitting a packet that will be received by every device on the network. In practice, the scope of the broadcast is limited to a broadcast domain.
Broadcasting is the most general communication method and is also the most intensive, in the sense that many messages may be required and many network devices are involved. This is in contrast to unicast addressing in which a host sends datagrams to another single host, identified by a unique address.
Broadcasting may be performed as all scatter in which each sender performs its own scatter in which the messages are distinct for each receiver, or all broadcast in which they are the same.
The MPI message passing method which is the de facto standard on large computer clusters includes the MPI_Alltoall method.
Not all network technologies support broadcast addressing; for example, neither X.25 nor Frame Relay have broadcast capability. The Internet Protocol Version 4 (IPv4), which is the primary networking protocol in use today on the Internet and all networks connected to it, supports broadcast, but the broadcast domain is the broadcasting host's subnet, which is typically small; there is no way to do an Internet- |
https://en.wikipedia.org/wiki/Passthrough%20%28electronics%29 | In signal processing, a passthrough is a logic gate that enables a signal to "pass through" unaltered, sometimes with little alteration. Sometimes the concept of a "passthrough" can also involve daisy chain logic.
Examples of passthroughs
Analog passthrough (for digital TV)
Sega 32X (passthrough for Sega Genesis video games)
VCRs, DVD recorders, etc. act as a "pass-through" for composite video and S-video, though sometimes they act as an RF modulator for use on Channel 3.
Tape monitor features allow an AV receiver (sometime the recording device itself) to act as a "pass-through" for audio.
An AV receiver usually allows pass-through of the video signal while amplifying the audio signal to drive speakers.
See also
Dongle, a device that converts signal, instead of just being a "passthrough" for unaltered signal
Signal processing
Electrical engineering
de:Durchschleifen |
https://en.wikipedia.org/wiki/List%20of%20parasites%20of%20humans |
Endoparasites
Protozoan organisms
Helminths (worms)
Helminth organisms (also called helminths or intestinal worms) include:
Tapeworms
Flukes
Roundworms
Other organisms
Ectoparasites |
https://en.wikipedia.org/wiki/Iranian%20Journal%20of%20Numerical%20Analysis%20and%20Optimization | The Iranian Journal of Numerical Analysis and Optimization is a quarterly peer-reviewed open-access scientific journal covering numerical analysis and optimization. It was established in 2008 and is published by the Ferdowsi University of Mashhad. The editor-in-chief is Ali. R. Soheili. The journal is indexed and abstracted in Scopus and zbMATH Open. |
https://en.wikipedia.org/wiki/Channel%20router | A channel router is a specific variety of router for integrated circuits. Normally using two layers of interconnect, it must connect the specified pins on the top and bottom of the channel. Specified nets must also be brought out to the left and right of the channel, but may be brought out in any order. The height of the channel is not specified - the router computes what height is needed.
The density of a channel, defined for every x within the channel, is the number of nets that appear on both the left and right of a vertical line at that x. The maximum density is a lower bound on the height of the channel. A "cyclic constraint" occurs when two pins occur in the same column (but with different orders) in at least two columns. In the example shown, nets 1 and 3 suffer from cyclic constraints. This can only be solved by "doglegs" as shown on net 1 of the example.
Channel routers were one of the first forms of routers for integrated circuits, and were heavily used for many years, with YACR perhaps the best known program. However, modern chips have many more than 2 interconnect layers. Although the effort was made to extend channel routers to more layers, this approach was never very popular, since it did not work well with over-the-cell routing where pins are not movable. In recent years, area routers have in general taken over. |
https://en.wikipedia.org/wiki/Zebra%20Media%20Access%20Control | Zebra Media Access Control (Z-MAC) is a network protocol for wireless sensor networks. It controls how a Media Access Control (MAC) accesses a common communication medium of a network.
Network protocols define specific details, such as how computers in a computer network exchange data. Sensor networks consist of tiny, wirelessly communicating sensor nodes which are deployed in large numbers in an area to network independently. While the sensors monitor their surroundings, their energy reserves are depleted. They constitute a special form of mobile ad-hoc network and make entirely different demands on a network protocol than, for example, the Internet.
Z-MAC was first introduced by Injong Rhee, Ajit Warrier, Mahesh Aia and Jeongki Min from North Carolina State University in 2005. The protocol is relevant to the protocols S-MAC, T-MAC, DSMAC, WiseMAC, μ-MAC and M-MAC.
Protocol structure
Z-MAC combines the two approaches Carrier Sense Multiple Access (CSMA) and Time Division Multiple Access (TDMA) so that the network behaves at low data load as in CSMA and high network traffic as in TDMA.
The protocol begins with a set-up phase, including the following four steps: construction of the network topology, distribution of time slots, exchanging of local time frame and network-wide synchronization. This initialization causes a high load on the network, which is made up for from the perspective of the developer with long service life and efficient data transfer.
Construction of the network topology
After activation, each sensor node transmits every second ping for 30 seconds. Pings are in the network technology brief messages that are sent back immediately from sender to receiver, usually to check connection and line quality. With Z-MAC, the ping contains information on the sending node itself and all the information that has been collected through the direct neighbors of the node. By pinging the environment experienced by a sensor node, the nodes it directly contacts |
https://en.wikipedia.org/wiki/Mobile%20Robot%20Programming%20Toolkit | The Mobile Robot Programming Toolkit (MRPT) is a cross-platform and open source C++ library aimed to help robotics researchers to design and implement algorithms related to Simultaneous Localization and Mapping (SLAM), computer vision and motion planning (obstacle avoidance). Different research groups have employed MRPT to implement projects reported in some of the major robotics journals and conferences.
MRPT is open source and distributed under the New BSD License. Versions prior to 1.0.0 were released under the GPL.
Some features included in the project as user-applications:
Visualization and manipulation of large datasets.
SLAM algorithms: incremental mapping with ICP, Extended Kalman filtering, Rao-Blackwellized particle filters and GraphSLAM.
Grabbing datasets from robotic sensors.
Upon a selection of the individual libraries provided by MRPT, users can develop new applications.
MRPT participated in Google Summer of Code in 2016–2018.
Representation of metric maps
Through polymorphism in the design of metric-map classes, observations (such as a laser scans) can be inserted into a grid-map or a map of points, or both simultaneously, transparently to the user.
The following representations of metric maps are implemented:
Occupancy grid maps.
Point maps.
Landmark maps: discrete elements are 3D points sensed through range and bearing. For example, visual landmarks.
Beacon maps: elements are also 3D points, but sensed by means of range-only devices.
Coloured point maps.
Gas concentration maps.
A "multi map", collections of any of the other maps, behaving as a single map.
See also
Webots - A Professional Mobile Robot Simulator (Commercial)
Microsoft Robotics Studio
Player Project
Robot software
Arduino |
https://en.wikipedia.org/wiki/Recursive%20filter | In signal processing, a recursive filter is a type of filter which reuses one or more of its outputs as an input. This feedback typically results in an unending impulse response (commonly referred to as infinite impulse response (IIR)), characterised by either exponentially growing, decaying, or sinusoidal signal output components.
However, a recursive filter does not always have an infinite impulse response. Some implementations of moving average filter are recursive filters but with a finite impulse response.
Non-recursive Filter Example:
y[n] = 0.5x[n − 1] + 0.5x[n].
Recursive Filter Example:
y[n] = 0.5y[n − 1] + 0.5x[n].
Examples of recursive filters
Kalman filter
Signal processing
Weblinks
IIR Filter Design auf Google Play Store |
https://en.wikipedia.org/wiki/Cholera%20riots | Cholera riots are civil disturbances associated with an outbreak or epidemic of cholera.
In Russia
Cholera riots (Холерные бунты in Russian) broke out among the urban population, peasants and soldiers in 1830–1831 when the second cholera pandemic reached Russia.
The riots were caused by the anti-cholera measures, undertaken by the tsarist government, such as quarantine, armed cordons and migratory restrictions. Influenced by rumors of deliberate contamination of ordinary people by government officials and doctors, agitated mobs started raiding police departments and state hospitals, killing hated functionaries, officers, landowners and gentry. In November 1830, the citizens of Tambov attacked their governor, but they were soon suppressed by the regular army. In June 1831, there was a riot on the Sennaya Square in St.Petersburg, but the agitated workers, artisans and house-serfs were dispersed by the army, reinforced with artillery. The riots went especially out of control in Sevastopol and in military settlements of the Novgorod guberniya. The rebels established their own court, electoral committees out of soldiers and non-commissioned officers and conducted propaganda among the serfs.
Further cholera riots in 1892 were aggressively suppressed by the tsarist government.
On August 29, 1909 The New York Times reported more cholera riots in Russia.
In Great Britain
Asiatic cholera reached Britain in 1831 from Russia, beginning in Sunderland and heading north to Aberdeen. A major riot took place in Aberdeen on 26 December 1831, when a dog dug up a dead body in the city. 20,000 Aberdonians (two-thirds of the city's population, although this number has been criticised as an exaggeration) protested against the medical establishment, which they believed were using the epidemic as a body-snatching scheme similar to the Burke and Hare murders of 1828:
Three men were brought to trial for riotous behaviour, and sentenced to jail in Aberdeen for twelve months, with the |
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