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https://en.wikipedia.org/wiki/Surrogation | Surrogation is a psychological phenomenon found in business practices whereby a measure of a construct of interest evolves to replace that construct. Research on performance measurement in management accounting identifies surrogation with "the tendency for managers to lose sight of the strategic construct(s) the measures are intended to represent, and subsequently act as though the measures are the constructs". An everyday example of surrogation is a manager tasked with increasing customer satisfaction who begins to believe that the customer satisfaction survey score actually is customer satisfaction.
First usage
Inspired by work by Yuji Ijiri, the term surrogation was coined by Willie Choi, Gary Hecht, and Bill Tayler in their paper, "Lost in Translation: The Effects of Incentive Compensation on Strategy Surrogation". They show managers tend to use measures as surrogates for strategy, acting as if measures were in fact the strategy when making optimization decisions. This appears to occur even if a measure-maximizing choice ultimately works against the strategy.
They also show surrogation is exacerbated by incentive compensation. But, the phenomenon is distinct from wealth-maximizing behavior, since it persists both when incentives are removed and when they are changed to create an opportunity cost for maximizing the surrogate. The additional tendency to surrogate in the presence of incentives is reduced when managers are compensated based on multiple measures of a strategy rather than on a single measure.
Choi, Hecht, and Tayler proposed attribute substitution as a mechanism for surrogation. Attribute substitution in decision-making involves a complex target attribute being replaced by a more easily accessible heuristic attribute. For this to occur, the target attribute must be relatively inaccessible, the heuristic attribute must be readily accessible, and the mental substitution must not be consciously rejected by the person. In the case of surrogation, the t |
https://en.wikipedia.org/wiki/Guvera | Guvera was an online music and entertainment streaming service founded in 2008. Guvera had agreements with the music labels in the regions where the product was available, which allowed for legal free music streams. As of May 2017, Guvera has shut down all operations across all remaining Asian markets.
Music streaming
Guvera streamed music and entertainment for its users and held licensing agreements with Universal Music Group, EMI, Orchard, INgrooves, IODA, Mushroom/Liberation, Shock Records, Believe Digital; in addition to the rights bodies APRA, AMCOS, BMI, RightsFlow, Acodem, SESAC, Cash, Emmasacm, Extraphone, Peer, Prs/Impel, Filscap, First Music Publishing, Latinautor, Macp, Megaliner, National Music Publishing, Sabam, Sadaic, Sba, Sacem, Siae, Socan, Sonyatv, Sesac, Sgae, Solar, Warner Chappell, Universal Music Publishing, and Unisys. Guvera distributed DRM-free MP3 downloads with bitrates of 256 and 320 kbit/s. Guvera was also a targeted advertising platform, which targeted ads at relevant music genres. Content could be streamed via brand channels from within Guvera's platform, and the advertisers had a role in the selecting music content.
Guvera was available on web browsers, iOS, Android and the Windows Phone.
History
Guvera was initially funded by AMMA Private Investment out of Australia. Guvera raised about $50m from its base of about 1000 smaller sophisticated investors primarily made up of accounting firms and other financial services businesses.
Guvera was incorporated in 2008, and launched beta in Australia February 2010, and in the US March, 2010. Guvera was initially released as a beta to a select group of users by invitation only.
On August 2011, Guvera appointed Phil Quartararo as its Global Head of Music. In September 2011 Guvera moved into new headquarters in The Rocket in Robina, Gold Coast, Australia. In March 2012, Guvera created a mobile platform and in December 2012, Guvera released mobile apps for IOS and Android in Australia. An iPad |
https://en.wikipedia.org/wiki/Gamma%20distribution | In probability theory and statistics, the gamma distribution is a two-parameter family of continuous probability distributions. The exponential distribution, Erlang distribution, and chi-squared distribution are special cases of the gamma distribution. There are two equivalent parameterizations in common use:
With a shape parameter and a scale parameter .
With a shape parameter and an inverse scale parameter , called a rate parameter.
In each of these forms, both parameters are positive real numbers.
The gamma distribution is the maximum entropy probability distribution (both with respect to a uniform base measure and a base measure) for a random variable for which E[X] = kθ = α/β is fixed and greater than zero, and E[ln(X)] = ψ(k) + ln(θ) = ψ(α) − ln(β) is fixed (ψ is the digamma function).
Definitions
The parameterization with k and θ appears to be more common in econometrics and other applied fields, where the gamma distribution is frequently used to model waiting times. For instance, in life testing, the waiting time until death is a random variable that is frequently modeled with a gamma distribution. See Hogg and Craig for an explicit motivation.
The parameterization with and is more common in Bayesian statistics, where the gamma distribution is used as a conjugate prior distribution for various types of inverse scale (rate) parameters, such as the λ of an exponential distribution or a Poisson distribution – or for that matter, the β of the gamma distribution itself. The closely related inverse-gamma distribution is used as a conjugate prior for scale parameters, such as the variance of a normal distribution.
If k is a positive integer, then the distribution represents an Erlang distribution; i.e., the sum of k independent exponentially distributed random variables, each of which has a mean of θ.
Characterization using shape α and rate β
The gamma distribution can be parameterized in terms of a shape parameter α = k and an inverse scale parame |
https://en.wikipedia.org/wiki/SPAdes%20%28software%29 | SPAdes (St. Petersburg genome assembler) is a genome assembly algorithm which was designed for single cell and multi-cells bacterial data sets. Therefore, it might not be suitable for large genomes projects.
SPAdes works with Ion Torrent, PacBio, Oxford Nanopore, and Illumina paired-end, mate-pairs and single reads.
SPAdes has been integrated into Galaxy pipelines by Guy Lionel and Philip Mabon.
Background
Studying the genome of single cells will help to track changes that occur in DNA over time or associated with exposure to different conditions. Additionally, many projects such as Human Microbiome Project and antibiotics discovery would greatly benefit from Single-cell sequencing (SCS). SCS has an advantage over sequencing DNA extracted from large number of cells. The problem of averaging out the significant variations between cells can be overcome by using SCS.
Experimental and computational technologies are being optimized to allow researchers to sequence single cells. For instance, amplification of DNA extracted from a single cell is one of the experimental challenges. To maximize the accuracy and quality of SCS, a uniform DNA amplification is needed. It was demonstrated that using multiple annealing and looping-based amplification cycles (MALBAC) for DNA amplification generates less biasness compared to polymerase chain reaction (PCR) or multiple displacement amplification (MDA). Furthermore, it has been recognized that the challenges facing SCS are computational rather than experimental. Currently available assembler, such as Velvet, String Graph Assembler (SGA) and EULER-SR, were not designed to handle SCS assembly. Assembly of single cell data is difficult due to non-uniform read coverage, variation in insert length, high levels of sequencing errors and chimeric reads. Therefore, the new algorithmic approach, SPAdes, was designed to address these issues.
SPAdes assembly approach
SPAdes uses k-mers for building the initial de Bruijn graph and on followi |
https://en.wikipedia.org/wiki/Rabies | Rabies is a viral disease that causes encephalitis in humans and other mammals. It was historically referred to as hydrophobia ("fear of water") due to the symptom of panic when presented with liquids to drink. Early symptoms can include fever and abnormal sensations at the site of exposure. These symptoms are followed by one or more of the following symptoms: nausea, vomiting, violent movements, uncontrolled excitement, fear of water, an inability to move parts of the body, confusion, and loss of consciousness. Once symptoms appear, the result is virtually always death, regardless of treatment. The time period between contracting the disease and the start of symptoms is usually one to three months but can vary from less than one week to more than one year. The time depends on the distance the virus must travel along peripheral nerves to reach the central nervous system.
Rabies is caused by lyssaviruses, including the rabies virus and Australian bat lyssavirus. It is spread when an infected animal bites or scratches a human or other animals. Saliva from an infected animal can also transmit rabies if the saliva comes into contact with the eyes, mouth, or nose. Globally, dogs are the most common animal involved. In countries where dogs commonly have the disease, more than 99% of rabies cases are the direct result of dog bites. In the Americas, bat bites are the most common source of rabies infections in humans, and less than 5% of cases are from dogs. Rodents are very rarely infected with rabies. The disease can be diagnosed only after the start of symptoms.
Animal control and vaccination programs have decreased the risk of rabies from dogs in a number of regions of the world. Immunizing people before they are exposed is recommended for those at high risk, including those who work with bats or who spend prolonged periods in areas of the world where rabies is common. In people who have been exposed to rabies, the rabies vaccine and sometimes rabies immunoglobulin are |
https://en.wikipedia.org/wiki/Sedimentisphaerales | Sedimentisphaerales is an order of aquatic bacteria.
See also
List of bacterial orders
List of bacteria genera |
https://en.wikipedia.org/wiki/Wave%E2%80%93particle%20duality%20relation | The wave–particle duality relation, often loosely referred to as the Englert–Greenberger–Yasin duality relation, or the Englert–Greenberger relation, relates the visibility, , of interference fringes with the definiteness, or distinguishability, , of the photons' paths in quantum optics. As an inequality:
Although it is treated as a single relation, it actually involves two separate relations, which mathematically look very similar. The first relation, derived by Greenberger and Yasin in 1988, is expressed as . It was later extended to, providing an equality for the case of pure quantum states by Jaeger, Shimony, and Vaidman in 1995. This relation involves correctly guessing which of the two paths the particle would have taken, based on the initial preparation. Here can be called the predictability. A year later Englert, in 1996, derived a related relation dealing with experimentally acquiring knowledge of the two paths using an apparatus, as opposed to predicting the path based on initial preparation. This relation is . Here is called the distinguishability.
The significance of the relations is that they express quantitatively the complementarity of wave and particle viewpoints in double-slit experiments. The complementarity principle in quantum mechanics, formulated by Niels Bohr, says that the wave and particle aspects of quantum objects cannot be observed at the same time. The wave–particle duality relations makes Bohr's statement more quantitative – an experiment can yield partial information about the wave and particle aspects of a photon simultaneously, but the more information a particular experiment gives about one, the less it will give about the other. The predictability which expresses the degree of probability with which path of the particle can be correctly guessed, and the distinguishability which is the degree to which one can experimentally acquire information about the path of the particle, are measures of the particle information, whil |
https://en.wikipedia.org/wiki/Simon%20problems | In mathematics, the Simon problems (or Simon's problems) are a series of fifteen questions posed in the year 2000 by Barry Simon, an American mathematical physicist. Inspired by other collections of mathematical problems and open conjectures, such as the famous list by David Hilbert, the Simon problems concern quantum operators. Eight of the problems pertain to anomalous spectral behavior of Schrödinger operators, and five concern operators that incorporate the Coulomb potential.
In 2014, Artur Avila won a Fields Medal for work including the solution of three Simon problems. Among these was the problem of proving that the set of energy levels of one particular abstract quantum system was in fact the Cantor set, a challenge known as the "Ten Martini Problem" after the reward that Mark Kac offered for solving it.
The 2000 list was a refinement of a similar set of problems that Simon had posed in 1984.
Context
Background definitions for the "Coulomb energies" problems ( nonrelativistic particles (electrons) in with spin and an infinitely heavy nucleus with charge and Coulombian mutual interaction):
is the space of functions on which are antisymmetric under exchange of the spin and space coordinates. Equivalently, the subspace of which is antisymmetric under exchange of the factors.
The Hamiltonian is . Here is the coordinate of the -th particle, is the Laplacian with respect to the coordinate . Even if the Hamiltonian does not explictly depend on the state of the spin sector, the presence of spin has an effect due to the antisymmetry condition on the total wavefunction.
We define , that is, the ground state energy of the system.
We define to be the smallest value of such that for all positive integers ; it is known that such a number always exists and is always between and , inclusive.
The 1984 list
Simon listed the following problems in 1984:
In 2000, Simon claimed that five of the problems he listed had been solved.
The 2000 list
The |
https://en.wikipedia.org/wiki/Commation%20eposianum | Commation eposianum is a species of heterotrophic protists discovered in 1993 in Antarctic waters. It is one of two species in the Commatiida, an order of stramenopiles closely related to actinophryids, a group of heliozoan protists, and to raphidophytes, a group of algae.
Etymology
The name of the species, "eposianum" references the initiative behind the EPOS joint-European Antarctic research programme, which allowed this species to be discovered through an expedition to the Southern Ocean. The name of the genus derives , which references the general biconvex shape of the cell.
Morphology
Commation eposianum is a species of unicellular eukaryotes composed of spherical biconvex cells measuring 7–12 μm. They present a narrow proboscis measuring 16–18 μm in length, relatively long in comparison to the proboscis of Commation cryoporinum. Their cytoskeleton consists of a spiralling band composed of a microtubular sheet associated with 3 crystalline, electron-dense structures. This band occupies one half of the cell and gets thinner from the periphery towards the center of the cell. Other structural microtubules arise from the surface of the cell nucleus. The cell has only one type of extrusome which is not visible under light microscopy, in contrast to Commation cryoporinum which presents two types of extrusomes that can be visible if large enough. |
https://en.wikipedia.org/wiki/Darwin%20%28programming%20language%29 | Darwin is a closed source programming language developed by Gaston Gonnet and colleagues at ETH Zurich. It is used to develop the OMA orthology inference software, which was also initially developed by Gonnet. The language backend consists of the kernel, responsible for performing simple mathematical calculations, for transporting and storing data and for interpreting the user's commands, and the library, a set of programs which can perform more complicated calculations. The target audience for the language is the biosciences, so the library consisted of routines such as those to compute pairwise alignments, phylogenetic trees, multiple sequence alignments, and to make secondary structure predictions.
Example Code
One would write the Hello World program as:
printf('Hello, world!\n');
The following procedure calculates the factorial of a number:
factorial := proc ( n )
if (n=0) then
return(1);
else
return(n * factorial(n-1));
fi;
end:
See also
List of programming languages |
https://en.wikipedia.org/wiki/Sardine%20run | The KwaZulu-Natal sardine run of southern Africa occurs from May through July when billions of sardines – or more specifically the Southern African pilchard Sardinops sagax – spawn in the cool waters of the Agulhas Bank and move northward along the east coast of South Africa. Their sheer numbers create a feeding frenzy along the coastline.
The run, containing millions of individual sardines, occurs when a current of cold water heads north from the Agulhas Bank up to Mozambique where it then leaves the coastline and goes further east into the Indian Ocean.
In terms of biomass, researchers estimate the sardine run could rival East Africa's great wildebeest migration. However, little is known of the phenomenon. It is believed that the water temperature has to drop below 21 °C in order for the migration to take place. In 2003, the sardines failed to 'run' for the third time in 23 years. While 2005 saw a good run, 2006 marked another non-run.
The shoals are often more than 7 km long, 1.5 km wide and 30 metres deep and are clearly visible from spotter planes or from the surface.
Sardines group together when they are threatened. This instinctual behaviour is a defence mechanism, as lone individuals are more likely to be eaten than when in large groups.
Causes
The sardine run is still poorly understood from an ecological point of view.
There have been various hypotheses, sometimes contradictory, that try to explain why and how the run occurs.
A recent interpretation of the causes is that the sardine run is most likely a seasonal reproductive migration of a genetically distinct subpopulation of sardine that moves along the coast from the eastern Agulhas Bank to the coast of KwaZulu-Natal in most years if not in every year.
Genomic and transcriptomic data indicate that the sardines participating in the run originate from South Africa's cool-temperate Atlantic coast. These are attracted to temporary cold-water upwelling off the south-east coast, and eventually find them |
https://en.wikipedia.org/wiki/Multimedia%20terminal%20mobile | The first integration between mobile phone and Palm (PDA Personal Device Assistant) occurred in 1999, as a result of an Italian–lead project submitted to the action line V1.1 CPA1 "Integrated application platforms and services" 5th Framework Program of the European Community (project number IST1999-11100).
The project, called MTM (Multimedia Terminal Mobile), was a multimedia platform, including both phone and PDA features; it also integrated the first miniature camera and a unidirectional microphone for video conferencing and commands interpretation through voice recognition.
The creator and coordinator of the project, Alessandro Pappa, worked in a team with other European partners:
PointerCom
Sirius Communication NV
Sistemas Expertos SA
Matla System
University of Avignon – LIA
Comune di Roma – Eurolaboratorio
DKFZ-MBI, Div. Medical and Biological Informatics, German Cancer Research Center
TZMI, Steinbeis-Transferzentrum Medizinische Informatik
Universidad Politécnica de Madrid
Clinica Femenia
Clinica Nuestra senora del Rosario
It was one of the larger projects accepted by the EC in terms of cost and numbers of project participants. It received a no refundable loan for more than 50% of the investments.
The MTM formed the basis of other international projects and started the video broadband communication technology.
Project goals
The major objectives of the MTM project were to:
Introduce a new generation of communication in the millennium 2000: through a mobile terminal, making phone calls using the new high bandwidth transmission technology and at the same time being able to see the other person in video conference.
Create an object capable of connecting to broadband for telephony and for Internet, with WEB navigation emailing, etc. Basically, having the office in your pocket.
The project in brief
The MTM project has created a Hardware platform, and four vertical applications: Easy City Guide, Distance Learning, Telemedicine and Speech and Speak |
https://en.wikipedia.org/wiki/X86%20virtualization | x86 virtualization is the use of hardware-assisted virtualization capabilities on an x86/x86-64 CPU.
In the late 1990s x86 virtualization was achieved by complex software techniques, necessary to compensate for the processor's lack of hardware-assisted virtualization capabilities while attaining reasonable performance. In 2005 and 2006, both Intel (VT-x) and AMD (AMD-V) introduced limited hardware virtualization support that allowed simpler virtualization software but offered very few speed benefits. Greater hardware support, which allowed substantial speed improvements, came with later processor models.
Software-based virtualization
The following discussion focuses only on virtualization of the x86 architecture protected mode.
In protected mode the operating system kernel runs at a higher privilege such as ring 0, and applications at a lower privilege such as ring 3. In software-based virtualization, a host OS has direct access to hardware while the guest OSs have limited access to hardware, just like any other application of the host OS. One approach used in x86 software-based virtualization to overcome this limitation is called ring deprivileging, which involves running the guest OS at a ring higher (lesser privileged) than 0.
Three techniques made virtualization of protected mode possible:
Binary translation is used to rewrite certain ring 0 instructions in terms of ring 3 instructions, such as POPF, that would otherwise fail silently or behave differently when executed above ring 0, making the classic trap-and-emulate virtualization impossible. To improve performance, the translated basic blocks need to be cached in a coherent way that detects code patching (used in VxDs for instance), the reuse of pages by the guest OS, or even self-modifying code.
A number of key data structures used by a processor need to be shadowed. Because most operating systems use paged virtual memory, and granting the guest OS direct access to the MMU would mean loss of control |
https://en.wikipedia.org/wiki/Central%20differencing%20scheme | In applied mathematics, the central differencing scheme is a finite difference method that optimizes the approximation for the differential operator in the central node of the considered patch and provides numerical solutions to differential equations. It is one of the schemes used to solve the integrated convection–diffusion equation and to calculate the transported property Φ at the e and w faces, where e and w are short for east and west (compass directions being customarily used to indicate directions on computational grids). The method's advantages are that it is easy to understand and implement, at least for simple material relations; and that its convergence rate is faster than some other finite differencing methods, such as forward and backward differencing. The right side of the convection-diffusion equation, which basically highlights the diffusion terms, can be represented using central difference approximation. To simplify the solution and analysis, linear interpolation can be used logically to compute the cell face values for the left side of this equation, which is nothing but the convective terms. Therefore, cell face values of property for a uniform grid can be written as:
Steady-state convection diffusion equation
The convection–diffusion equation is a collective representation of diffusion and convection equations, and describes or explains every physical phenomenon involving convection and diffusion in the transference of particles, energy and other physical quantities inside a physical system:
where is diffusion coefficient and is the property.
Formulation of steady-state convection diffusion equation
Formal integration of steady-state convection–diffusion equation over a control volume gives
This equation represents flux balance in a control volume. The left side gives the net convective flux, and the right side contains the net diffusive flux and the generation or destruction of the property within the control volume.
In the absence of |
https://en.wikipedia.org/wiki/Witching%20hour | In folklore, the witching hour or devil's hour is a time of night that is associated with supernatural events, whereby witches, demons and ghosts are thought to appear and be at their most powerful. Definitions vary, and include the hour immediately after midnight, and the time between 3:00am and 4:00am. The term now has a widespread colloquial and idiomatic usage that is associated with human physiology and behaviour to more superstitious phenomena such as luck.
Origins
The phrase "witching hour" began at least as early as 1775, in the poem "Night, an Ode." by Rev. Matthew West, though its origins may go further back to 1535 when the Catholic Church prohibited activities during the 3:00 am and 4:00 am timeframe due to emerging fears about witchcraft in Europe.
In the Western Christian tradition, the hour between 3:00 am and 4:00 am was considered a period of peak supernatural activity—this time is also referred to as the "Devil's hour" due to it being a mocking inversion of the time in which Jesus supposedly died, which was at 3:00 pm.
Time
There are multiple times that can be considered the witching hour. Some claim the time is between 12:00 am and 1:00 am, while others claim there is increased supernatural activity between sunset and sunrise. The New Zealand Oxford Dictionary identifies midnight as the time when witches are supposedly active.
During the time in which this term originated, many people had sleeping schedules that meant they were awake during the middle of the night. Nonetheless, there is psychological literature suggesting that apparitional experiences and sensed presences are most common between the hours of 2:00 am and 4:00 am, corresponding with a 3:00 am peak in the amount of melatonin in the body.
Physiology
The witching hour may stem to a human's sleep cycle and circadian rhythm – the body is going through REM sleep at that time, where the heart rate is slower, body temperature reduced, breathing pattern and blood pressure irregular. Su |
https://en.wikipedia.org/wiki/TCP%20congestion%20control | Transmission Control Protocol (TCP) uses a congestion control algorithm that includes various aspects of an additive increase/multiplicative decrease (AIMD) scheme, along with other schemes including slow start and congestion window (CWND), to achieve congestion avoidance. The TCP congestion-avoidance algorithm is the primary basis for congestion control in the Internet. Per the end-to-end principle, congestion control is largely a function of internet hosts, not the network itself. There are several variations and versions of the algorithm implemented in protocol stacks of operating systems of computers that connect to the Internet.
To avoid congestive collapse, TCP uses multi-faceted congestion-control strategy. For each connection, TCP maintains a CWND, limiting the total number of unacknowledged packets that may be in transit end-to-end. This is somewhat analogous to TCP's sliding window used for flow control.
Additive increase/multiplicative decrease
The additive increase/multiplicative decrease (AIMD) algorithm is a closed-loop control algorithm. AIMD combines linear growth of the congestion window with an exponential reduction when a congestion takes place. Multiple flows using AIMD congestion control will eventually converge to use equal amounts of a contended link.
This is the algorithm that is described in for the "congestion avoidance" state.
Congestion window
In TCP, the congestion window (CWND) is one of the factors that determines the number of bytes that can be sent out at any time. The congestion window is maintained by the sender and is a means of stopping a link between the sender and the receiver from becoming overloaded with too much traffic. This should not be confused with the sliding window maintained by the sender which exists to prevent the receiver from becoming overloaded. The congestion window is calculated by estimating how much congestion there is on the link.
When a connection is set up, the congestion window, a value maintai |
https://en.wikipedia.org/wiki/Medical%20education%20agency | Medical education agencies are a specialty subset of advertising agencies that develop educational content for the Healthcare, Life Science and Biotechnology industries. Medical education agencies are divided into two categories:
CME
Medical education agencies that develop Continuing medical education (most commonly referred to as CME) programs in the United States, do so within the strict guidelines set forth by the Accreditation Council for Continuing Medical Education (ACCME) and the Society for Academic Continuing Medical Education (SACME). Those who wish to offer CME courses, and thus employ the services of a medical education agency, must receive accreditation from the ACCME. Accreditation allows organizations, such as the American Nursing Certification Center (ANCC) to develop educational course content that physicians and other professional medical staff may use to satisfy annual CME requirements.
To avoid the risk of undue bias from commercial sponsorship, all accredited organizations must follow the commercial disclosure rules set out by the ACCME. Medical education agencies must familiarize themselves with these regulations in order to receive CME accreditation from one or more ACCME accredited organizations.
Non-CME
Medical education agencies that develop Non-CME, also referred to as Promotional education, programs specialize in developing content whose commercial sponsorship is clearly outlined, and course content focuses on specific products or therapies in which the sponsoring organization has a financial interest.
Delivery Mechanisms
The majority of content developed by medical education agencies supports one of two types of delivery mechanism: Instructor Led Training (ILT) and Self Directed Training (SDT).
Instructor Led Training
Instructor led training, ILT, is the practice of face-to-face delivery of information and learning material between an instructor and learners. Instructor lead training can take the form of didactic training, la |
https://en.wikipedia.org/wiki/Transgenic%20hydra | Cnidarians such as Hydra have become attractive model organisms to study the evolution of immunity. However, despite long-term efforts, stably transgenic animals could not be generated, severely limiting the functional analysis of genes. For analytical purposes, therefore, an important technical breakthrough in the field was the development of a transgenic procedure for generation of stably transgenic lines by embryo microinjection.
Uses
Hydra polyps are small and transparent which makes it possible to trace single cells in vivo. In addition, transgenic Hydra provide a ready system for generating gain-of-function phenotypes. With the use of transgenes producing dominant-negative versions of proteins, one should be able to obtain loss-of-function phenotypes as well.
Current technology allows generation of reporter constructs using promoters of various Hydra genes fused to fluorescent proteins.
Since transgenic Hydra lines have become an important tool to dissect molecular mechanisms of development, a “Hydra Transgenic Facility” has been established at the Christian-Albrechts-University of Kiel (Germany). |
https://en.wikipedia.org/wiki/Regeneration%20%28ecology%29 | In ecology regeneration is the ability of an ecosystemspecifically, the environment and its living populationto renew and recover from damage. It is a kind of biological regeneration.
Regeneration refers to ecosystems replenishing what is being eaten, disturbed, or harvested. Regeneration's biggest force is photosynthesis which transforms sun energy and nutrients into plant biomass. Resilience to minor disturbances is one characteristic feature of healthy ecosystems. Following major (lethal) disturbances, such as a fire or pest outbreak in a forest, an immediate return to the previous dynamic equilibrium will not be possible. Instead, pioneering species will occupy, compete for space, and establish themselves in the newly opened habitat. The new growth of seedlings and community assembly process is known as regeneration in ecology. As ecological succession sets in, a forest will slowly regenerate towards its former state within the succession (climax or any intermediate stage), provided that all outer parameters (climate, soil fertility availability of nutrients, animal migration paths, air pollution or the absence thereof, etc.) remain unchanged.
In certain regions like Australia, natural wildfire is a necessary condition for a cyclically stable ecosystem with cyclic regeneration.
Artificial disturbances
While natural disturbances are usually fully compensated by the rules of ecological succession, human interference can significantly alter the regenerative homeostatic faculties of an ecosystem up to a degree that self-healing will not be possible. For regeneration to occur, active restoration must be attempted.
See also
Bush regeneration
Biocapacity
Ecological stability
Ecoscaping
Forest ecology
Net Primary Productivity
Pioneer species
Regenerative design
Regenerative agriculture
Soil regeneration |
https://en.wikipedia.org/wiki/Appia%20%28software%29 | Appia is a free and open-source layered communication toolkit implemented in Java, and licensed under the Apache License, version 2.0. It was born in the University of Lisbon, Portugal, by the DIALNP research group that is hosted in the LaSIGE research unit.
Components
Appia is composed by a core that is used to compose protocols, and a set of protocols that provide group communication, ordering guaranties, atomic broadcast, among other properties.
Core
The Appia core offers a clean way for the application to express inter-channel constraints. This feature is obtained as an extension to the functionality provided by current systems. Thus, Appia retains a flexible and modular design that allows communication stacks to be composed and reconfigured in run-time.
Protocols
The existing protocols include interface with TCP and UDP sockets, virtual synchrony, several implementations of total order, causal order, among others.
See also
Protocol stack |
https://en.wikipedia.org/wiki/Astromundus | Astromundus was a 2-years Erasmus Mundus masters course in Astronomy and Astrophysics. It was offered by a consortium of 5 partner universities of four different European countries. Partner universities were University of Innsbruck in Austria, University of Padova and University of Rome Tor Vergata in Italy, University of Göttingen in Germany and University of Belgrade in Serbia. Belgrade was a third country partner of this consortium.
Main objective of this masters course was to provide students from all over the world with a state-of-the-art background in Astrophysics which would be useful in their future research career. Also, as typical of all other Erasmus Mundus programs, it encourages cultural exchange between different countries. The first edition of AstroMundus officially started on September 22, 2010 in Innsbruck. The welcome reception was held at Claudiasaal, a historical landmark of Innsbruck. The AstroMundus programme ended with the conclusion of the 8th course edition in January 2020.
Topics of interest
Courses offered by Astromundus are mainly on these topics. They span throughout almost all the branches of Modern Astronomy, Astrophysics and Cosmology.
Galactic Astrophysics (the Sun and the Solar System, the Milky Way, stellar evolution, the interstellar medium)
Planetology and Astrobiology (including Extrasolar planets)
Extragalactic Astrophysics (galaxies, galaxy evolution, galaxy clusters, intracluster medium, star formation)
Active Galactic Nuclei (including accretion theory, relativistic jets, modelling)
Cosmology (including observational cosmology, galaxy surveys, gravitational lensing, very early universe)
Particle Cosmology
Astroparticle physics
Gravitational waves
Observational astrophysics from the ground and from space (including Radio, X-ray, optical)
Computational astrophysics (N-body simulations, magneto-hydrodynamic simulations, High energy physics with CERN)
Scholarships
Like all Erasmus Mundus programmes, Astromundus was |
https://en.wikipedia.org/wiki/Ron%20Orp%27s%20Mail | Ron Orp's Mail is an e-mail newsletter which is sent each weekday, from Monday to Friday, to subscribers in a dozen cities in Europe and the Americas.
Romano Strebel and Christian Klinner started Ron Orp's Mail in 2004 in Zurich, Switzerland. Initially it covered only Zurich, with news about the city’s cultural, gastronomic and party offerings, and also tips concerning music, media, reading and TV. Trends and new projects from the city as well as from around the globe are covered. The public market place is another important element of the newsletter. There inserts are published which have previously been advertised on the affiliated homepage.
The newsletter is nominally published by Ron Orp, but he is never seen and there is disagreement as to whether he exists or is a marketing gimmick.
History
2004: The first issue of Ron Orp’s Mail is sent to 100 subscribers in Zurich on April 29, 2004. Within nine months, subscriptions reach 1000.
2005–2006: In December 2006, subscriptions reach 13,500. At that time, all content for the newsletter is compiled by only three people on a voluntary basis.
2007: Website and newsletter undergo a redesign. Additionally, the newsletter expands to Vienna, Basel, Bern, Lucerne, and Winterthur. In December 2007, subscriptions reach 25,000.
2008: The number of subscribers continues to rise and reaches 41,000 by December 2008. More than 20 people now work for Ron Orp’s Mail in the various cities. Expansion to St. Gallen and also New York City, Berlin and Munich. A weekly English-language version is also launched in Zurich (appears every Thursday).
2009: Website and newsletter undergo a second redesign. The number of subscribers reaches a new peak of 63,000.
2010: Ron Orp expands further, to French-speaking Switzerland (Geneva), Brazil (Brasília) and the UK (London). Ron Orp Zurich launches a digital magazine for the city called Ron Orp’s Magazine and an iPhone app. In December 2010, Ron Orp is awarded the title Digital Marketer of t |
https://en.wikipedia.org/wiki/The%20Collapse%20of%20Chaos | The Collapse of Chaos: Discovering Simplicity in a Complex World (1994) is a book about complexity theory and the nature of scientific explanation written by biologist Jack Cohen and mathematician Ian Stewart.
In this book Cohen and Stewart give their ideas on chaos theory, particularly on how the simple leads to the complex, and conversely, how the complex leads to the simple, and argue for a need for contextual explanation in science as a complement to reduction. This book dovetails with other books written by the Cohen-Stewart team, particularly Figments of Reality.
As with other Cohen-Stewart books, topics are illustrated with humorous science fiction snippets dealing with a fictional alien intelligence, the Zarathustrians, whom Cohen and Stewart use as metaphors of the human mind itself.
Reception
Next Generation commented, "Although the book assumes you have zero knowledge of science (and thus is a little patronizing in the early chapters), it presents the concepts of Complexity Theory as well as anything we've seen."
Additional reviews |
https://en.wikipedia.org/wiki/Alpaca | The alpaca (Lama pacos) is a species of South American camelid mammal. It is similar to, and often confused with, the llama. However, alpacas are often noticeably smaller than llamas. The two animals are closely related and can successfully crossbreed. Both species are believed to have been domesticated from their wild relatives, the vicuña and guanaco. There are two breeds of alpaca: the Suri alpaca and the Huacaya alpaca.
Alpacas are kept in herds that graze on the level heights of the Andes of Southern Peru, Western Bolivia, Ecuador, and Northern Chile at an altitude of above sea level. Alpacas are considerably smaller than llamas, and unlike llamas, they were not bred to be working animals, but were bred specifically for their fiber. Alpaca fiber is used for making knitted and woven items, similar to sheep's wool. These items include blankets, sweaters, hats, gloves, scarves, a wide variety of textiles, and ponchos, in South America, as well as sweaters, socks, coats, and bedding in other parts of the world. The fiber comes in more than 52 natural colors as classified in Peru, 12 as classified in Australia, and 16 as classified in the United States.
Alpacas communicate through body language. The most common is spitting to show dominance when they are in distress, fearful, or feel agitated. Male alpacas are more aggressive than females, and tend to establish dominance within their herd group. In some cases, alpha males will immobilize the head and neck of a weaker or challenging male in order to show their strength and dominance.
In the textile industry, "alpaca" primarily refers to the hair of Peruvian alpacas, but more broadly it refers to a style of fabric originally made from alpaca hair, such as mohair, Icelandic sheep wool, or even high-quality wool from other breeds of sheep. In trade, distinctions are made between alpacas and the several styles of mohair and luster.
An adult alpaca generally is between in height at the shoulders (withers). They usua |
https://en.wikipedia.org/wiki/Self-certifying%20File%20System | In computing, Self-certifying File System (SFS) is a global and decentralized, distributed file system for Unix-like operating systems, while also providing transparent encryption of communications as well as authentication. It aims to be the universal distributed file system by providing uniform access to any available server, however, the usefulness of SFS is limited by the low deployment of SFS clients. It was developed in the June 2000 doctoral thesis of David Mazières.
Implementation
The SFS client daemon implements the Sun's Network File System (NFS) protocol for communicating with the operating system, and thus can work on any operating system that supports NFS, including Windows. The client manages connections to remote file systems as necessary, acting as a kind of protocol translation layer. The SFS server works similarly to other distributed file system servers, by exposing an existing disk file system over the network, over the specific SFS protocol. On Unix-like systems, SFS file systems can usually be found at . When an SFS file system is first accessed through this path, a connection to the server is made and the directory is created ("automounted").
Differences
The primary motivation behind the file system is to address the shortcomings of hardwired, administratively configured distributed file systems in larger organizations, and various remote file transfer protocols. It is designed to operate securely between separate administrative realms. For example, with SFS, one could store all their files on a single remote server, and access the same files securely and transparently from any location as if they were stored locally, without any special privileges or administrative cooperation (other than running the SFS client daemon). Available file systems will be found at the same path regardless of physical location, and are implicitly authenticated by their path names — as they include the public-key fingerprint of the server (hence why it is called |
https://en.wikipedia.org/wiki/Boris%20Korenblum | Boris Isaac Korenblum (Борис Исаакович Коренблюм, 12 August 1923, Odessa, now Ukraine – 15 December 2011, Slingerlands, New York) was a Soviet-Israeli-American mathematician, specializing in mathematical analysis.
Boris Korenblum was a child prodigy in music, languages, and mathematics. He started as a violinist at the famous School of Stolyarsky in Odessa. After he won a young mathematicians competition, the family was given an apartment in Kiev, an extraordinary event. Boris was given a mentor, a local mathematics professor, who would peremptorily supervise his course of self study. To the great chagrin of his mother, Boris decided against pursuing a music career. In June 1941, when the war began, he volunteered, not yet having reached the draft age, for the Soviet Army. Because of his fluency in German, he served in a reconnaissance unit. Some of his tasks was going to the enemy lines to capture a prisoner for interrogation. He was also the one to interpret to his commanding officers when a prisoner was taken. Once, refusing to beat a prisoner who was talking already, he quarrelled with the superior officer, and was punished by being sent to a penal battalion. There, he served with, and made fast wartime friends with, some rough characters, many of whom were discharged from penal colonies "to wash with their blood the offences against the Motherland." He later told his family that this experience, together with the inevitable maturing during a bloody war, made a man out of a soft city boy with a doting Jewish mother. After some time, the need for competent interpreters saw him return to his unit, where he served with distinction to the end of the war. His awards, including an Order of the Red Banner, were taken from him when he emigrated to Israel in November 1973.
Coming home from the war, he passed all the exams for the undergraduate degree in mathematics in a few of months, and was admitted for graduate study at the Institute of Mathematics of the National |
https://en.wikipedia.org/wiki/Sexing%20the%20Body | Sexing the Body: Gender Politics and the Construction of Sexuality is a 2000 book by the biologist Anne Fausto-Sterling, in which the author explores the social construction of gender, and the social and medical treatment of intersex people. Her stated goal is to "convince readers of the need for theories that allow for a good deal of human variation and that integrate the analytical powers of the biological and the social into the systematic analysis of human development."
Background
This book was published in the same year as As Nature Made Him, a book by John Colapinto about David Reimer that further debunked the gender theories of John Money. The examination and critique in Sexing the Body of the theories advanced by Money therefore lack the additional details uncovered by Colapinto.
Critical reception
In a review for Politics and the Life Sciences, Laurette T. Liesen writes the book is "based on the premise that science is a social construction in which "created truths" about sex and gender are imposed on individuals" and "In a rather circular argument, Fausto-Sterling describes how studies on sexual differences in genetics, hormones, and the brain, as well as medical practices used on intersexuals, are gender-biased." A review in Hypatia by Heidi E. Grasswick notes that Fausto-Sterling uses the metaphor of a möbius strip "in an effort to describe not only the organization of the book, but more importantly, the complex nature of the relationship between the social and the material that she is striving to articulate through her detailed analyses of particular research programs."
According to Publishers Weekly, "As in her now classic book, Myths of Gender, Fausto-Sterling draws on a wealth of scientific and medical information, along with social, anthropological and feminist theory, to make the case that "choosing which criteria to use in determining sex, and choosing to make the determination at all, are social decisions for which scientists can offer no abs |
https://en.wikipedia.org/wiki/Markov%20spectrum | In mathematics, the Markov spectrum devised by Andrey Markov is a complicated set of real numbers arising in Markov Diophantine equation and also in the theory of Diophantine approximation.
Quadratic form characterization
Consider a quadratic form given by f(x,y) = ax2 + bxy + cy2 and suppose that its discriminant is fixed, say equal to −1/4. In other words, b2 − 4ac = 1.
One can ask for the minimal value achieved by when it is evaluated at non-zero vectors of the grid , and if this minimum does not exist, for the infimum.
The Markov spectrum M is the set obtained by repeating this search with different quadratic forms with discriminant fixed to −1/4:
Lagrange spectrum
Starting from Hurwitz's theorem on Diophantine approximation, that any real number has a sequence of rational approximations m/n tending to it with
it is possible to ask for each value of 1/c with 1/c ≥ about the existence of some for which
for such a sequence, for which c is the best possible (maximal) value. Such 1/c make up the Lagrange spectrum L, a set of real numbers at least (which is the smallest value of the spectrum). The formulation with the reciprocal is awkward, but the traditional definition invites it; looking at the set of c instead allows a definition instead by means of an inferior limit. For that, consider
where m is chosen as an integer function of n to make the difference minimal. This is a function of , and the reciprocal of the Lagrange spectrum is the range of values it takes on irrational numbers.
Relation with Markov spectrum
The initial part of the Lagrange spectrum, namely the part lying in the interval , is equal to the Markov spectrum. The first few values are , , /5, /13, ... and the nth number of this sequence (that is, the nth Lagrange number) can be calculated from the nth Markov number by the formulaFreiman's constant is the name given to the end of the last gap in the Lagrange spectrum, namely:
.
Real numbers greater than F are also members of |
https://en.wikipedia.org/wiki/Ehrenpreis%20conjecture | In mathematics, the Ehrenpreis conjecture of Leon Ehrenpreis states that for any K greater than 1, any two closed Riemann surfaces of genus at least 2 have finite-degree covers which are K-quasiconformal: that is, the covers are arbitrarily close in the Teichmüller metric.
A proof was announced by Jeremy Kahn and Vladimir Markovic in January 2011, using their proof of the Surface subgroup conjecture and a newly developed "good pants homology" theory. In June 2012, Kahn and Markovic were given the Clay Research Awards for their work on these two problems by the Clay Mathematics Institute at a ceremony at Oxford University.
See also
Surface subgroup conjecture
Virtually Haken conjecture
Virtually fibered conjecture |
https://en.wikipedia.org/wiki/FinVect | In the mathematical field of category theory, FinVect (or FdVect) is the category whose objects are all finite-dimensional vector spaces and whose morphisms are all linear maps between them.
Properties
FinVect has two monoidal products:
the direct sum of vector spaces, which is both a categorical product and a coproduct,
the tensor product, which makes FinVect a compact closed category.
Examples
Tensor networks are string diagrams interpreted in FinVect.
Group representations are functors from groups, seen as one-object categories, into FinVect.
DisCoCat models are monoidal functors from a pregroup grammar to FinVect.
See also
FinSet
ZX-calculus
category of modules |
https://en.wikipedia.org/wiki/Corvette%20%28computer%29 | Corvette () was an 8-bit personal computer in the USSR, created for Soviet schools in 1980s. The first device was a homemade computer, created in 1985 by employees of the Moscow State University for their purposes (physics experiments). The first description was made in the magazine «Microprocessor tools and systems». The PC was named "ПК 8001" (21.08.1985).
Graphics
This computer had advanced graphic capabilities for its time. It has only one video mode which uses 4 planes: 3 graphic and 1 text. The graphic planes have 512x256 resolution. The text plane is capable to show 32x16 or 64x16 text using two sets of 256 ROM 8x16 characters for both modes. It possible to show 16 colors on screen. 8 colors are free and 8 additional colors can be used combining text symbols and pixels. Any logical color may be any physical color from 0 to 15 (RGBI). The graphic video RAM size is 192 KB (4 pages) or 48 KB (1 page). The text video RAM size is 1 KB which is 9-bit static RAM. The 9th bit is used as the reverse video attribute. There is no contention for access to video and processor RAM. The Corvette has a way to accelerate filling an area with a given color. It could be faster than the IBM PC AT with the EGA card for this task.
Sound
One channel of the Intel 8253 is used to generate sound.
Software
BASIC interpreter in ROM, fully compliant with the MSX standard, including all graphic commands (drawing points, lines, rectangles, filled rectangles, circles, ellipses, arcs, closed area filling, DRAW), working with integers, etc.
Operation systems MicroDOS (МикроДОС) and CP/M-80 (with floppy disk driver)
Text editor «Супертекст», «Микромир» (MIM), etc.
DBMS dBase II
Spreadsheet Microsoft Multiplan
Compilers for Fortran, Pascal, C, Ada, Forth, Lisp, PL/M, etc.
Software for education
Games («Berkut», PopCorn, Stalker, Dan Dare, Continental Circus, Deflector, «Treasure», «Winnie the Pooh», «Treasure Island», Super Tetris, Karate, etc.)
Educational computer te |
https://en.wikipedia.org/wiki/Blooming%20%28geometry%29 | In the geometry of convex polyhedra, blooming or continuous blooming is a continuous three-dimensional motion of the surface of the polyhedron, cut to form a polyhedral net, from the polyhedron into a flat and non-self-overlapping placement of the net in a plane. As in rigid origami, the polygons of the net must remain individually flat throughout the motion, and are not allowed to intersect or cross through each other. A blooming, reversed to go from the flat net to a polyhedron, can be thought of intuitively as a way to fold the polyhedron from a paper net without bending the paper except at its designated creases.
An early work on blooming by Biedl, Lubiw, and Sun from 1999 showed that some nets for non-convex but topologically spherical polyhedra have no blooming.
The question of whether every convex polyhedron admits a net with a blooming was posed by Robert Connelly, and came to be known as Connelly’s blooming conjecture. More specifically, Miller and Pak suggested in 2003 that the source unfolding, a net that cuts the polyhedral surface at points with more than one shortest geodesic to a designated source point (including cuts across faces of the polyhedron), always has a blooming. This was proven in 2009 by Demaine et al., who showed in addition that every convex polyhedral net whose polygons are connected in a single path has a blooming, and that every net can be refined to a path-connected net. It is unknown whether every net of a convex polyhedron has a blooming, and Miller and Pak were unwilling to make a conjecture in either direction on this question.
Because it is unknown whether every convex polyhedron has a net that cuts only edges of the polyhedron, and not across its faces ("Dürer's conjecture"), it is also unknown whether every convex polyhedron has a blooming that cuts only edges. In an unpublished manuscript from 2009, Igor Pak and Rom Pinchasi have claimed that this is indeed possible for every Archimedean solid.
The problem of finding a |
https://en.wikipedia.org/wiki/Nakajima%E2%80%93Zwanzig%20equation | The Nakajima–Zwanzig equation (named after the physicists who developed it, Sadao Nakajima and Robert Zwanzig) is an integral equation describing the time evolution of the "relevant" part of a quantum-mechanical system. It is formulated in the density matrix formalism and can be regarded a generalization of the master equation.
The equation belongs to the Mori-Zwanzig formalism within the statistical mechanics of irreversible processes (named after Hazime Mori). By means of a projection operator the dynamics is split into a slow, collective part (relevant part) and a rapidly fluctuating irrelevant part. The goal is to develop dynamical equations for the collective part.
Derivation
The starting point is the quantum mechanical version of the von Neumann equation, also known as the Liouville equation:
where the Liouville operator is defined as .
The density operator (density matrix) is split by means of a projection operator
into two parts
,
where . The projection operator selects the aforementioned relevant part from the density operator, for which an equation of motion is to be derived.
The Liouville – von Neumann equation can thus be represented as
The second line is formally solved as
By plugging the solution into the first equation, we obtain the Nakajima–Zwanzig equation:
Under the assumption that the inhomogeneous term vanishes and using
as well as
we obtain the final form
See also
Redfield equation
Notes |
https://en.wikipedia.org/wiki/List%20of%20biomolecules | This is a list of articles that describe particular biomolecules or types of biomolecules.
A
For substances with an A- or α- prefix such as
α-amylase, please see the parent page (in this case Amylase).
A23187 (Calcimycin, Calcium Ionophore)
Abamectine
Abietic acid
Acetic acid
Acetylcholine
Actin
Actinomycin D
Adenine
Adenosmeme
Adenosine diphosphate (ADP)
Adenosine monophosphate (AMP)
Adenosine triphosphate (ATP)
Adenylate cyclase
Adiponectin
Adonitol
Adrenaline, epinephrine
Adrenocorticotropic hormone (ACTH)
Aequorin
Aflatoxin
Agar
Alamethicin
Alanine
Albumins
Aldosterone
Aleurone
Alpha-amanitin
Alpha-MSH (Melaninocyte stimulating hormone)
Allantoin
Allethrin
α-Amanatin, see Alpha-amanitin
Amino acid
Amylase (also see α-amylase)
Anabolic steroid
Anandamide (ANA)
Androgen
Anethole
Angiotensinogen
Anisomycin
Antidiuretic hormone (ADH)
Anti-Müllerian hormone (AMH)
Arabinose
Arginine
Argonaute
Ascomycin
Ascorbic acid (vitamin C)
Asparagine
Aspartic acid
Asymmetric dimethylarginine
ATP synthase
Atrial-natriuretic peptide (ANP)
Auxin
Avidin
Azadirachtin A – C35H44O16
B
Bacteriocin
Beauvericin
beta-Hydroxy beta-methylbutyric acid
beta-Hydroxybutyric acid
Bicuculline
Bilirubin
Biopolymer
Biotin (Vitamin H)
Brefeldin A
Brassinolide
Brucine
Butyric acid
C
Cadaverine
Caffeine
Calciferol (Vitamin D)
Calcitonin
Calmodulin
Calreticulin
Camphor - (C10H16O)
Cannabinol - (C21H26O2)
Capsaicin
Carbohydrase
Carbohydrate
Carnitine
Carrageenan
Carotinoid
Casein
Caspase
Catecholamine
Cellulase
Cellulose - (C6H10O5)x
Cerulenin
Cetrimonium bromide (Cetrimide) - C19H42BrN
Chelerythrine
Chromomycin A3
Chaparonin
Chitin
α-Chloralose
Chlorophyll
Cholecystokinin (CCK)
Cholesterol
Choline
Chondroitin sulfate
Cinnamaldehyde
Citral
Citric acid
Citrinin
Citronellal
Citronellol
Citrulline
Cobalamin (vitamin B12)
Coenzyme
Coenzyme Q
Colchicine
Collagen
Coniine
Corticosteroid
Corti |
https://en.wikipedia.org/wiki/Flory%E2%80%93Rehner%20equation | In polymer science Flory–Rehner equation is an equation that describes the mixing of polymer and liquid molecules as predicted by the equilibrium swelling theory of Flory and Rehner.
It describes the equilibrium swelling of a lightly crosslinked polymer in terms of crosslink density and the quality of the solvent.
The Flory–Rehner equation is written as:
where, is the volume fraction of polymer in the swollen mass, the molar volume of the solvent, is the number of network chain segments bounded on both ends by crosslinks, and is the Flory solvent-polymer interaction term.
In its full form, the Flory–Rehner equation is written as:
where, is the specific volume of the polymer, is the primary molecular mass, and is the average molecular mass between crosslinks or the network parameter.
Flory–Rehner theory
The Flory–Rehner theory gives the change of free energy upon swelling of the polymer gel similar to the Flory–Huggins solution theory:
.
The theory considers forces arising from three sources:
The entropy change caused by mixing of polymer and solvent
The heat of mixing of polymer and solvent , which may be positive, negative, or zero so, that
The entropy change caused by reduction in numbers of possible chain conformations via swelling
The Flory–Rehner equation was used to model the cooking of steaks in a journal article in 2020 |
https://en.wikipedia.org/wiki/Rotating%20ring-disk%20electrode | In analytical chemistry, a rotating ring-disk electrode (RRDE) is a double working electrode used in hydrodynamic voltammetry, very similar to a rotating disk electrode (RDE). The electrode rotates during experiments inducing a flux of analyte to the electrode. This system used in electrochemical studies when investigating reaction mechanisms related to redox chemistry and other chemical phenomena.
Structure
The difference between a rotating ring-disk electrode and a rotating disk electrode is the addition of a second working electrode in the form of a ring around the central disk of the first working electrode. To operate such an electrode, it is necessary to use a potentiostat, such as a bipotentiostat, capable of controlling a four-electrode system. The two electrodes are separated by a non-conductive barrier and connected to the potentiostat through different leads. This rotating hydrodynamic electrode motif can be extended to rotating double-ring electrodes, rotating double-ring-disk electrodes, and even more esoteric constructions, as suited to the experiment.
Function
The RRDE takes advantage of the laminar flow created during rotation. As the system is rotated, the solution in contact with the electrode is driven to its side, similar to the situation of a rotating disk electrode. As the solution flows to the side, it crosses the ring electrode and flows back into the bulk solution. If the flow in the solution is laminar, the solution is brought in contact with the disk and with the ring quickly afterward, in a very controlled manner. The resulting currents depend on the potential, area, and spacing of the electrodes, as well as the rotation speed and the substrate.
This design makes a variety of experiments possible, for example a complex could be oxidized at the disk and then reduced back to the starting material at the ring. It is easy to predict what the ring/disk current ratios is if this process is entirely controlled by the flow of solu |
https://en.wikipedia.org/wiki/Flat%20rate | A flat fee, also referred to as a flat rate or a linear rate refers to a pricing structure that charges a single fixed fee for a service, regardless of usage. Less commonly, the term may refer to a rate that does not vary with usage or time of use.
Advantages
A business can develop a dependable stance in a market, as consumers have a well-rounded price before the service is undertaken. For instance, a technician may charge $150 for his labor.
Potential costs can be covered. The service may result in inevitable expenses like the parts needed to fix the issue or the items required to complete the order.
No restricted structure is needed, as the pricing system can be adjusted to suit the business using it. Management can thus work out the pricing that best matches the company's objectives, efforts, costs, etc.
Disadvantages
The fixed pricing restricts the company's capability to meet the needs of individual consumers, and people search for cheaper alternatives.
Pricing competition thickens, with other companies in the same industry compete for the lowest pricing, and tough competition occurs.
Inflation can cause unprecedented losses, and companies must raise the charge to keep up with costs.
Examples
Postage
There are flat rates in the postal service, regarding the delivery of items. Postage companies use different forms of post, boxes or envelopes, to avoid having to weigh items. The on-hand cost lets consumers identify the cost and removes the hassle of estimate the cost for items.
The United States Postal Service offers flat-rate pricing for packages selling different postage options varying in size and shape. That provides consumers with an array of options upfront, creating a sense of ease. When shipped in higher volumes, it saves money but there are issues if both the flat rate and regular delivery systems are used simultaneously.
Advertising
Flat rate also passes into advertising. Purchasing advertisements on websites such as Facebook, Twitter a |
https://en.wikipedia.org/wiki/Bacillus%20subtilis%20BSR%20sRNAs | In a screen of the Bacillus subtilis genome for genes encoding ncRNAs, Saito et al. focused on 123 intergenic regions (IGRs) over 500 base pairs in length, the authors analyzed expression from these regions. Seven IGRs termed bsrC, bsrD, bsrE, bsrF, bsrG, bsrH and bsrI expressed RNAs smaller than 380 nt. All the small RNAs except BsrD RNA were expressed in transformed Escherichia coli cells harboring a plasmid with PCR-amplified IGRs of B. subtilis, indicating that their own promoters independently express small RNAs. Under non-stressed condition, depletion of the genes for the small RNAs did not affect growth. Although their functions are unknown, gene expression profiles at several time points showed that most of the genes except for bsrD were expressed during the vegetative phase (4–6 h), but undetectable during the stationary phase (8 h). Mapping the 5' ends of the 6 small RNAs revealed that the genes for BsrE, BsrF, BsrG, BsrH, and BsrI RNAs are preceded by a recognition site for RNA polymerase sigma factor σA.
Type I Toxin/Antitoxin system
It was shown that bsrE, bsrG and bsrH pair through intermolecular interactions with newly identified antisense sRNAs. It was suggested that they form type I toxin/antitoxin system that includes an mRNA encoding for a short, toxic peptide (bsrE, bsrG and bsrH ) and an antitoxin that consists of an antisense RNA.
Further studies established that the 294-nucleotide bsrG encodes a 39-amino-acid toxin, and the 180 nucleotide antisense sRNA called SR4 acts as the antitoxin (they overlap by 123 nucleotides). SR4 interaction with the 3'UTR of bsrG RNA promotes bsrG degradation and inhibits its translation. BsrG interferes with cell envelope biosynthesis, causes membrane invaginations and delocalisation of the cell wall synthesis and initiates autolysis.
The 256 nucleotide bsrE RNA encodes 30 amino-acid toxin peptide. Its antitoxin gene, SR5 overlaps by 112 nucleotides at the 3' end of bsrE. The antitoxin SR5 promotes bsrE |
https://en.wikipedia.org/wiki/Cytomics | Cytomics is the study of cell biology (cytology) and biochemistry in cellular systems at the single cell level. It combines all the bioinformatic knowledge to attempt to understand the molecular architecture and functionality of the cell system (Cytome). Much of this is achieved by using molecular and microscopic techniques that allow the various components of a cell to be visualised as they interact in vivo.
Cytome
Cytomes are the cellular systems, subsystems, and functional components of the
body. The cytome is the collection of the complex and dynamic cellular processes (structure and function) underlying physiological processes. It describes the structural and functional heterogeneity of the cellular diversity of an organism.
Human Cytome Project
The Human Cytome Project is aimed at the study of the biological system structure and function of an organism at the cytome level.
See also
Flow cytometry
Genomics
Omics
Proteomics
Lipidomics
List of omics topics in biology
Metabolomics |
https://en.wikipedia.org/wiki/Normal%20plane%20%28geometry%29 | A normal plane is any plane containing the normal vector of a surface at a particular point.
The normal plane also refers to the plane that is perpendicular to the tangent vector of a space curve; (this plane also contains the normal vector) see Frenet–Serret formulas.
Normal section
The normal section of a surface at a particular point is the curve produced by the intersection of that surface with a normal plane.
The curvature of the normal section is called the normal curvature.
If the surface is bow or cylinder shaped, the maximum and the minimum of these curvatures are the principal curvatures.
If the surface is saddle shaped the maxima of both sides are the principal curvatures.
The product of the principal curvatures is the Gaussian curvature of the surface (negative for saddle shaped surfaces).
The mean of the principal curvatures is the mean curvature of the surface; if (and only if) the mean curvature is zero, the surface is called a minimal surface.
See also
Earth normal section
Normal bundle
Normal curvature
Osculating plane
Principal curvature
Tangent plane (geometry) |
https://en.wikipedia.org/wiki/Biological%20membrane | A biological membrane, biomembrane or cell membrane is a selectively permeable membrane that separates the interior of a cell from the external environment or creates intracellular compartments by serving as a boundary between one part of the cell and another. Biological membranes, in the form of eukaryotic cell membranes, consist of a phospholipid bilayer with embedded, integral and peripheral proteins used in communication and transportation of chemicals and ions. The bulk of lipids in a cell membrane provides a fluid matrix for proteins to rotate and laterally diffuse for physiological functioning. Proteins are adapted to high membrane fluidity environment of the lipid bilayer with the presence of an annular lipid shell, consisting of lipid molecules bound tightly to the surface of integral membrane proteins. The cell membranes are different from the isolating tissues formed by layers of cells, such as mucous membranes, basement membranes, and serous membranes.
Composition
Asymmetry
The lipid bilayer consists of two layers- an outer leaflet and an inner leaflet. The components of bilayers are distributed unequally between the two surfaces to create asymmetry between the outer and inner surfaces. This asymmetric organization is important for cell functions such as cell signaling. The asymmetry of the biological membrane reflects the different functions of the two leaflets of the membrane. As seen in the fluid membrane model of the phospholipid bilayer, the outer leaflet and inner leaflet of the membrane are asymmetrical in their composition. Certain proteins and lipids rest only on one surface of the membrane and not the other.
• Both the plasma membrane and internal membranes have cytosolic and exoplasmic faces
• This orientation is maintained during membrane trafficking – proteins, lipids, glycoconjugates facing the lumen of the ER and Golgi get expressed on the extracellular side of the plasma membrane. In eucaryotic cells, new phospholipids are manufactur |
https://en.wikipedia.org/wiki/Bad%20command%20or%20file%20name | "Bad command or file name" is a common and ambiguous error message in MS-DOS and some other operating systems.
COMMAND.COM, the primary user interface of MS-DOS, produces this error message when the first word of a command could not be interpreted. For MS-DOS, this word must be the name of an internal command, executable file or batch file, so the error message provided an accurate description of the problem but easily confused novices. Though the source of the error had to be the first word (often a mistyped command), the wording gave the impression that files named in later words were damaged or had illegal filenames. Later, the wording of the error message was changed for clarity. Windows NT displays the following error message instead (where "foo" is replaced by the word causing error):
Some early Unix shells produced the equally cryptic "" for the same reasons. Most modern shells produce an error message similar to "".
See also
Abort, Retry, Fail?
List of DOS commands |
https://en.wikipedia.org/wiki/Electro-hydraulic%20actuator | Electro-hydraulic actuators (EHAs), replace hydraulic systems with self-contained actuators operated solely by electrical power. EHAs eliminate the need for separate hydraulic pumps and tubing, because they include their own pump, simplifying system architectures and improving safety and reliability. This technology originally was developed for the aerospace industry but has since expanded into many other industries where hydraulic power is commonly used.
Conventional designs
Aircraft were originally controlled by small aerodynamic surfaces operated by cables, attached to levers that magnified the pilot's input, using mechanical advantage. As aircraft grew in size and performance, the aerodynamic forces on these surfaces grew to the point where it was no longer possible for the pilot to manually control them across a wide range of speeds - controls with enough advantage to control the aircraft at high speed left the aircraft with significant overcontrol at lower speeds when the aerodynamic forces were reduced. Numerous aircraft in the early stages of World War II suffered from these problems, notably the Mitsubishi Zero and P-38 Lightning.
Starting in the 1940s, hydraulics were introduced to address these problems. In their early incarnations, hydraulic pumps attached to the engines fed high-pressure oil through tubes to the various control surfaces. Here, small valves were attached to the original control cables, controlling the flow of oil into an associated actuator connected to the control surface. One of the earliest fittings of a hydraulic boost system was to ailerons on late-war models of the P-38L, removing the need for great human strength to achieve a higher rate of roll.
The systems evolved, replacing the mechanical linkages to the valves with electrical controls, producing the "fly-by-wire" design, and more recently, optical networking systems called "fly-by-light". All these systems require three separate components, the hydraulic supply system, the |
https://en.wikipedia.org/wiki/Mathnasium | Mathnasium (also Mathnasium Learning Center) is an American education brand and supplemental math learning franchise consisting of over 1,000 learning centers in North America, South America, Europe, the Middle East, and Asia that provides instruction to students in pre-kindergarten through high school. The curriculum employs the Mathnasium Method, a proprietary system that was developed by a team of education experts with co-founder Lawrence Martinek.
History
Martinek, a Los Angeles-based mathematics educator, began writing his own supplemental materials to school curricula. In 1985, Martinek published Math Tips for Parents, a guide for parents and teachers based on his own experiences and his work with his son. He argues that a student's dislike of math stems from the frustration and embarrassment of not understanding math the way it is taught, and that students build confidence and mastery in mathematics through successful encounter and interaction with carefully selected materials. He emphasized that an approach combining oral, visual, mental, tactile and written modalities helps children to develop number sense.
Mathnasium was founded in 2002 by Larry Martinek, David Ullendorff, and Peter Markovitz. The first center opened in Westwood, Los Angeles, California, and continues to be one of a small number of centers owned by Mathnasium, LLC. The company began franchising in 2003. In 2019, the company has more than 1,000 centers on five continents. In 2019, the franchise expanded to Australia.
Programs
The Mathnasium approach first revolves around an assessment to determine what a student does and does not know. Next, a personalized and prescriptive learning program is made. Each student follows the program with the help of specially trained Mathnasium math instructors who provide instruction and encouragement. For proof of progress, Mathnasium relies on its assessments, as well as students' report cards, independent tests, and parent testimony to measure the spe |
https://en.wikipedia.org/wiki/Ghabrivirales | Ghabrivirales is an order of double-stranded RNA viruses. It is the only order in the class Chrysmotiviricetes. The name of the class is a portmanteau of member families: chrysoviridae, megabirnaviridae, and totiviridae; and -viricetes which is the suffix for a virus class. The name of the order derives from Said Ghabrial, a pioneering researcher who studied viruses in this order, and -virales which is the suffix for a virus order.
Taxonomy
The following families are recognized:
Chrysoviridae
Megabirnaviridae
Quadriviridae
Totiviridae |
https://en.wikipedia.org/wiki/Entropy%20coding | In information theory, an entropy coding (or entropy encoding) is any lossless data compression method that attempts to approach the lower bound declared by Shannon's source coding theorem, which states that any lossless data compression method must have expected code length greater or equal to the entropy of the source.
More precisely, the source coding theorem states that for any source distribution, the expected code length satisfies , where is the number of symbols in a code word, is the coding function, is the number of symbols used to make output codes and is the probability of the source symbol. An entropy coding attempts to approach this lower bound.
Two of the most common entropy coding techniques are Huffman coding and arithmetic coding.
If the approximate entropy characteristics of a data stream are known in advance (especially for signal compression), a simpler static code may be useful.
These static codes include universal codes (such as Elias gamma coding or Fibonacci coding) and Golomb codes (such as unary coding or Rice coding).
Since 2014, data compressors have started using the asymmetric numeral systems family of entropy coding techniques, which allows combination of the compression ratio of arithmetic coding with a processing cost similar to Huffman coding.
Entropy as a measure of similarity
Besides using entropy coding as a way to compress digital data, an entropy encoder can also be used to measure the amount of similarity between streams of data and already existing classes of data. This is done by generating an entropy coder/compressor for each class of data; unknown data is then classified by feeding the uncompressed data to each compressor and seeing which compressor yields the highest compression. The coder with the best compression is probably the coder trained on the data that was most similar to the unknown data.
See also
Arithmetic coding
Asymmetric numeral systems (ANS)
Context-adaptive binary arithmetic coding (CABAC |
https://en.wikipedia.org/wiki/Active%20queue%20management | In routers and switches, active queue management (AQM) is the policy of dropping packets inside a buffer associated with a network interface controller (NIC) before that buffer becomes full, often with the goal of reducing network congestion or improving end-to-end latency. This task is performed by the network scheduler, which for this purpose uses various algorithms such as random early detection (RED), Explicit Congestion Notification (ECN), or controlled delay (CoDel). RFC 7567 recommends active queue management as a best practice.
Overview
An Internet router typically maintains a set of queues, one or more per interface, that hold packets scheduled to go out on that interface. Historically, such queues use a drop-tail discipline: a packet is put onto the queue if the queue is shorter than its maximum size (measured in packets or in bytes), and dropped otherwise.
Active queue disciplines drop or mark packets before the queue is full. Typically, they operate by maintaining one or more drop/mark probabilities, and occasionally dropping or marking packets according to the probabilities before the queue is full.
Benefits
Drop-tail queues have a tendency to penalise bursty flows, and to cause global synchronisation between flows. By dropping packets probabilistically, AQM disciplines typically avoid both of these issues.
By providing endpoints with congestion indication before the queue is full, AQM disciplines are able to maintain a shorter queue length than drop-tail queues, which combats bufferbloat and reduces network latency.
Drawbacks
Early AQM disciplines (notably RED and SRED) require careful tuning of their parameters in order to provide good performance. These systems are not optimally behaved from a control theory perspective. Modern AQM disciplines (ARED, Blue, PI, CoDel, CAKE) are self-tuning, and can be run with their default parameters in most circumstances.
Network engineers have historically been trained to avoid packet loss, and have ther |
https://en.wikipedia.org/wiki/Weierstrass%20functions | In mathematics, the Weierstrass functions are special functions of a complex variable that are auxiliary to the Weierstrass elliptic function. They are named for Karl Weierstrass. The relation between the sigma, zeta, and functions is analogous to that between the sine, cotangent, and squared cosecant functions: the logarithmic derivative of the sine is the cotangent, whose derivative is negative the squared cosecant.
Weierstrass sigma function
The Weierstrass sigma function associated to a two-dimensional lattice is defined to be the product
where denotes or are a fundamental pair of periods.
Through careful manipulation of the Weierstrass factorization theorem as it relates also to the sine function, another potentially more manageable infinite product definition is
for any with and where we have used the notation (see zeta function below).
Weierstrass zeta function
The Weierstrass zeta function is defined by the sum
The Weierstrass zeta function is the logarithmic derivative of the sigma-function. The zeta function can be rewritten as:
where is the Eisenstein series of weight 2k + 2.
The derivative of the zeta function is , where is the Weierstrass elliptic function.
The Weierstrass zeta function should not be confused with the Riemann zeta function in number theory.
Weierstrass eta function
The Weierstrass eta function is defined to be
and any w in the lattice
This is well-defined, i.e. only depends on the lattice vector w. The Weierstrass eta function should not be confused with either the Dedekind eta function or the Dirichlet eta function.
Weierstrass ℘-function
The Weierstrass p-function is related to the zeta function by
The Weierstrass ℘-function is an even elliptic function of order N=2 with a double pole at each lattice point and no other poles.
Degenerate case
Consider the situation where one period is real, which we can scale to be and the other is taken to the limit of so that the functions are only singly-periodic. |
https://en.wikipedia.org/wiki/192%20%28number%29 | 192 (one hundred [and] ninety-two) is the natural number following 191 and preceding 193.
In mathematics
192 has the prime factorization . Because it has so many small prime factors, it is the smallest number with 14 divisors, namely 1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, and 192 itself. Because its only prime factors are 2 and 3, it is a 3-smooth number.
192 is the sum of ten consecutive primes (5 + 7 + 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37).
192 is a Leyland number of the second kind.
See also
192 (disambiguation) |
https://en.wikipedia.org/wiki/Tesla%20Automation | Tesla Automation GmbH (formerly Grohmann Engineering GmbH) is a German engineering automation company based in Prüm in the state of Rhineland-Palatinate. The company operates a development center in Neutraubling, Bavaria, as well as support offices in Chandler, Arizona, and Shanghai, China. The company was founded in 1983 by Klaus Grohmann and acquired by Tesla, Inc., in January 2017. Klaus Grohmann was ousted after clashing with Tesla CEO Elon Musk.
The product portfolio includes machinery for the production of microprocessors and memory chips, airbag sensors and power steering controllers, as well as systems for the production of car door and roof seals, lithium-ion battery cells and modules. Among other things, the company manufactures robotics that are used in the production of batteries and electronics.
The firm works closely with universities within dual track studies of Mechanical Engineering and Robotic Process Automation. In addition, it provides training in the field of Technical Product Design, Industrial Mechanics, CNC Operation, Construction Technology, IT, Mechatronics and Industrial Electronic Technology.
History
Grohmann Engineering was founded by Klaus Grohmann in 1963. It moved its headquarters to Prüm in 1983.
In November 2016, the privately held company agreed to be acquired by the American automotive company Tesla Motors. At the time, 74.9% of the company was owned by Klaus Grohmann and 25.1% was owned by the . At the time, the company had 700 employees, with annual revenues of about €120 million. The deal was completed on 3 January 2017, at which point the company employed 800 people. According to a May 2017 SEC filing, Tesla paid $109.5 million in cash for the company, and in addition paid $25.8 million for a new incentive compensation agreement.
In April 2017, founder Klaus Grohmann left the company due to a dispute with Tesla CEO Elon Musk. Musk demanded the company halt production for competitors, such as BMW and Daimler AG, to focus |
https://en.wikipedia.org/wiki/Biotic%20homogenization | Biotic homogenization is the process by which two or more spatially distributed ecological communities become increasingly similar over time. This process may be genetic, taxonomic, or functional, and it leads to a loss of beta (β) diversity. While the term is sometimes used interchangeably with "taxonomic homogenization", "functional homogenization", and "genetic homogenization", biotic homogenization is actually an overarching concept that encompasses the other three. This phenomenon stems primarily from two sources: extinctions of native and invasions of nonnative species. While this process pre-dates human civilization, as evidenced by the fossil record, and still occurs due to natural impacts, it has recently been accelerated due anthropogenic pressures. Biotic homogenization has become recognized as a significant component of the biodiversity crisis, and as such has become of increasing importance to conservation ecologists.
Overview
Homogenization versus differentiation
Homogenization is the process of assemblages becoming increasingly similar: the reverse is the process of assemblages becoming increasingly different over time, a process known as "biotic differentiation". Just as biotic homogenization has genetic, taxonomic, and functional components, differentiation can occur at any of these levels of organization.
Alpha and beta diversity
Understanding homogenization requires an understanding of the difference between alpha (α) and beta (β) diversity. Alpha diversity refers to diversity within a community: it addresses how many species are present. A community with high α diversity has many species present. Beta diversity compares multiple communities. For there to be high β diversity, two communities would have to have high α diversity but have different, unique species compositions.
Species introduction, extinction, and richness
When organisms are introduced to a habitat, be it naturally or artificially, overall species richness increases (assumin |
https://en.wikipedia.org/wiki/Software%20bot | A software bot is a type of software agent in the service of software project management and software engineering. A software bot has an identity and potentially personified aspects in order to serve their stakeholders. Software bots often compose software services and provide an alternative user interface, which is sometimes, but not necessarily conversational.
Software bots are typically used to execute tasks, suggest actions, engage in dialogue, and promote social and cultural aspects of a software project.
The term bot is derived from robot. However, robots act in the physical world and software bots act only in digital spaces. Some software bots are designed and behave as chatbots, but not all chatbots are software bots. Erlenhov et al. discuss the past and future of software bots and show that software bots have been adopted for many years.
Usage
Software bots are used to support development activities, such as communication among software developers and automation of repetitive tasks. Software bots have been adopted by several communities related to software development, such as open-source communities on GitHub and Stack Overflow.
GitHub bots have user accounts and can open, close, or comment on pull requests and issues. GitHub bots have been used to assign reviewers, ask contributors to sign the Contributor License Agreement, report continuous integration failures, review code and pull requests, welcome newcomers, run automated tests, merge pull requests, fix bugs and vulnerabilities, etc.
The Slack tool includes an API for developing software bots. There are slack bots for keeping track of todo lists, coordinating standup meetings, and managing support tickets. The
Chatbot company products further simplify the process of creating a custom Slack bot.
On Wikipedia, Wikipedia bots automate a variety of tasks, such as creating stub articles, consistently updating the format of multiple articles, and so on. Bots like ClueBot NG are capable of recogniz |
https://en.wikipedia.org/wiki/Gra%C5%BEvydas%20Lukinavi%C4%8Dius | Gražvydas Lukinavičius is a Lithuanian biochemist. His scientific interest and main area of research is focused on labeling of biomolecules and visualization using super-resolution microscopy. He is co-invertor of DNA labeling technology known as Methyltransferase-Directed Transfer of Activated Groups (mTAG) and biocompatible and cell permeable fluorophore – silicon-rhodamine (SiR). Both inventions were commercialized. He is studying labeling methods and apply them for chromatin dynamics visualization in living cells.
Early life
He was born in the family of an electrician and a land development specialist. Lukinavičius finished secondary school in Jurbarkas.
Research
Lukinavičius completed his bachelor's degree and master's degree in biochemistry at the Vilnius University in 2000 and 2002 respectively. During this period he worked as a research assistant in Saulius Klimašauskas group and investigating conformational movements of the catalytic loop of DNA methyltransferase.
Later he became interested in S-Adenosyl methionine analogues which can be cofactors for methyltransferases. He collaborated with Elmar Weinhold from RWTH Aachen University and learned chemical synthesis and received his PhD in biochemistry at Vilnius University, Lithuania in September 2007. This led to the development of a new DNA labeling method, the Methyltransferase-Directed Transfer of Activated Groups (mTAG). This method was applied for optical DNA mapping and for a profiling epigenetic modifications by several research groups.
After obtaining his PhD, he moved to École polytechnique fédérale de Lausanne for postdoctoral research where he continued on working with protein labeling methods in group of Kai Johnsson. He improved SNAP-tag protein labelling technology by developing a new biocompatible fluorophore, silicon-rhodamine (SiR). During this period, he began a collaboration with Stefan Hell to perform one of the first super-resolution microscopy experiments of living cells.
In |
https://en.wikipedia.org/wiki/Agaricus%20pattersoniae | Agaricus pattersoniae is an edible species of mushroom. It is found in the United States, where it associates with cypress trees. It has been proposed for inclusion in the IUCN Red List of Threatened Species.
Taxonomy
It was first described in the literature in 1907 by Charles Horton Peck, based on specimens found by , a botany student at Stanford University. She found fruit bodies on Stanford campus in January, where they were growing under pine and cypress trees. The specific epithet was originally spelled "Pattersonae" by Peck, although this is now considered an orthographic variant. This species was placed in section Sanguinolenti of genus Agaricus but in the related section Nigrobrunnescentes when this is considered separate.
Description
The cap, in diameter, is initially almost hemispherical in shape, transforming to broadly convex and finally to flattened or with edges upturned in age. The cap surface is dry, with fibrils when young, but later the fibrils form large, dark brown appressed squamules (2–9 mm long by 2–5 mm broad). The cap color may be various shades of brown depending on the maturity of the specimen. The cap flesh is typically thick, firm, white, and stains deep red 20–30 seconds after injury or bruising. The odor immediately after cutting is mild, faintly spicy, but several minutes may be described as 'fruity'. An edible mushroom, the taste of A. pattersoniae is described as mild, pleasant, and slightly sweet.
The gills are free in attachment, closely spaced, broad, and marginate. The light-cinnamon color in young specimens turns to a dark blackish brown in age after the spores develop. Bruised gills stain a vinaceous (wine-colored) red.
The stipe is usually long by thick with a bulbous shape. The interior is hollow, with the internal cavity being between thick. The stipe context somewhat fibrous and white in color, except for the basal section which is yellowish. Bruising or cutting results in a red stain after a minute. The surface |
https://en.wikipedia.org/wiki/Climate%20Data%20Record | A Climate Data Record (CDR) is a specific definition of a climate data series, developed by the Committee on Climate Data Records from NOAA Operational Satellites of the National Research Council at the request of NOAA in the context of satellite records. It is defined as "a time series of measurements of sufficient length, consistency, and continuity to determine climate variability and climate change.".
Such measurements provide an objective basis for the understanding and prediction of climate and its variability, such as global warming.
Interim Climate Data Record (ICDR)
An Interim Climate Data Record (ICDR) is a dataset that has been forward processed, using the baselined CDR algorithm and processing environment but whose consistency and continuity have not been verified. Eventually it will be necessary to perform a new reprocessing of the CDR and ICDR parts together to guarantee consistency, and the new reprocessed data record will replace the old CDR.
Fundamental Climate Data Record (FCDR)
A Fundamental Climate Data Record is a long-term data record of calibrated and quality-controlled data designed to allow the generation of homogeneous products that are accurate and stable enough for climate monitoring.
Examples of CDRs
AVHRR Pathfinder Sea Surface Temperature
GHRSST-PP Reanalysis Project, on the website for Ghrsst-pp
Snow and Ice
NOAA's Climate Data Records homepage
See also
Temperature record |
https://en.wikipedia.org/wiki/Bogey%20value | In manufacturers' specifications for electronic devices, a bogey device (or bogie device) - especially a vacuum tube- is one that has all characteristics equal to the published values, in other words that its parameters all lie in the centre of their bell curve distributions.
Parameter value
A bogey is a published value for a parameter of an electronic component, such as a vacuum tube, that is average or typical of devices that will be sold, and which the device's manufacturer is attempting to achieve. With manufacturing tolerances and variables in production, most devices produced do not exactly meet the bogey value for each parameter.
Apart from a bogey device being a theoretical device that has the given characteristics, the term can refer to a specially-selected example of a device (e.g. from a production run where care is taken to ensure each characteristic has its nominal value); for example a bogey tube could be used to calibrate tube testers and be expected to give readings in the middle of the meter's "good" region. Hence a tube can be specified by its bogey values and suitable tolerances, and tests are based on the bogey values. For applications such as music amplifiers where the channels need to have nearly identical performance, it is desirable that components are matched and have major parameter values close to bogey. |
https://en.wikipedia.org/wiki/Roskamp%20Institute | The Roskamp Institute, was co-founded by Robert and Diane Roskamp, and Fiona Crawford and Michael Mullan in Sarasota, Florida in 2003. It is a nonprofit biomedical research facility specializing neurological research including Alzheimer's disease, traumatic brain injury, Gulf War syndrome, and posttraumatic stress disorder. It also operates an onsite neurology clinic. The institute is focused on finding the causes and treatments for neuropsychiatric and neurodegenerative diseases.
The institute's lead researchers, Michael Mullan and Fiona Crawford, were members of a team of scientists who discovered the first genetic errors causing Alzheimer's disease in 1991 in the APP gene in early onset familial cases. Mullan and Crawford also discovered the Swedish mutation which has been incorporated into transgenic mice which are widely used to understand the disease and test new treatments.
The institute is particularly focused on translational research that can lead to novel drug or other therapeutic interventions in neurodegenerative disorders. In this regard, Institute scientists discovered that certain members of a class of drugs called dihydropyridines [DHPs] can lower the levels of amyloid beta in the brains of transgenic models of the disease and decided to take one of them, nilvadipine, forward into clinical trials for Alzheimer's disease. This work was conducted by Archer Pharmaceuticals, a for-profit spin off of the institute, headed by Mullan. In partnership with colleagues at Trinity College, Dublin led by Brian Lawlor, Archer and Institute scientists conducted an open label phase I/II trial of nilvadipine in mild to moderate Alzheimer's disease subjects. More recently, in collaboration with multiple partners at academic institutes in Europe, and again led by Lawlor, Archer and Roskamp Institute scientists partnered to conduct a phase III clinical trial of nilvadipine in mild to moderate Alzheimer's disease.
The institute is currently housed in a scientific r |
https://en.wikipedia.org/wiki/Bulgarian%20solitaire | In mathematics and game theory, Bulgarian solitaire is a card game that was introduced by Martin Gardner.
In the game, a pack of cards is divided into several piles. Then for each pile, remove one card; collect the removed cards together to form a new pile (piles of zero size are ignored).
If is a triangular number (that is, for some ), then it is known that Bulgarian solitaire will reach a stable configuration in which the sizes of the piles are . This state is reached in moves or fewer. If is not triangular, no stable configuration exists and a limit cycle is reached.
Random Bulgarian solitaire
In random Bulgarian solitaire or stochastic Bulgarian solitaire a pack of cards is divided into several piles. Then for each pile, either leave it intact or, with a fixed probability , remove one card; collect the removed cards together to form a new pile (piles of zero size are ignored). This is a finite irreducible Markov chain.
In 2004, Brazilian probabilist of Russian origin Serguei Popov showed that stochastic Bulgarian solitaire spends "most" of its time in a "roughly" triangular distribution. |
https://en.wikipedia.org/wiki/Angular%20momentum%20coupling | In quantum mechanics, angular momentum coupling is the procedure of constructing eigenstates of total angular momentum out of eigenstates of separate angular momenta. For instance, the orbit and spin of a single particle can interact through spin–orbit interaction, in which case the complete physical picture must include spin–orbit coupling. Or two charged particles, each with a well-defined angular momentum, may interact by Coulomb forces, in which case coupling of the two one-particle angular momenta to a total angular momentum is a useful step in the solution of the two-particle Schrödinger equation.
In both cases the separate angular momenta are no longer constants of motion, but the sum of the two angular momenta usually still is. Angular momentum coupling in atoms is of importance in atomic spectroscopy. Angular momentum coupling of electron spins is of importance in quantum chemistry. Also in the nuclear shell model angular momentum coupling is ubiquitous.
In astronomy, spin–orbit coupling reflects the general law of conservation of angular momentum, which holds for celestial systems as well. In simple cases, the direction of the angular momentum vector is neglected, and the spin–orbit coupling is the ratio between the frequency with which a planet or other celestial body spins about its own axis to that with which it orbits another body. This is more commonly known as orbital resonance. Often, the underlying physical effects are tidal forces.
General theory and detailed origin
Angular momentum conservation
Conservation of angular momentum is the principle that the total angular momentum of a system has a constant magnitude and direction if the system is subjected to no external torque. Angular momentum is a property of a physical system that is a constant of motion (also referred to as a conserved property, time-independent and well-defined) in two situations:
The system experiences a spherically symmetric potential field.
The system moves (in qu |
https://en.wikipedia.org/wiki/El-Ouali%20Mustapha%20Sayed | El-Ouali Mustapha Sayed (also known as El Uali, El-Wali, Luali or Lulei; ; 1949 – 9 June 1976) was a Sahrawi nationalist leader, co-founder and second Secretary-General of the Polisario Front.
Youth and background
El-Ouali was born in 1949 in a Sahrawi nomad encampment somewhere on the hammada desert plains in eastern Spanish Sahara or northern Mauritania; some sources give his place of birth as Bir Lehlou, a location that is symbolic for the Polisario Front, for being the place of the proclamation of the Sahrawi Arab Democratic Republic (SADR). His parents were poor and his father disabled, and with the sum of the severe drought on the Sahara that year, and the consequences of the Ifni War, the family had to abandon the traditional bedouin lifestyle of the Sahrawis, settling near Tan-Tan (nowadays southern Morocco) at the late 1950s. Some sources stated that Ouali's family was deported among others to Morocco by Spanish authorities in 1960.
He went to Primary School in Tan-Tan in 1962, and then to the Islamic Institute in Taroudannt in 1966 with impressive results, being awarded scholarships to attend university in Rabat in 1970. There he studied Laws & Political sciences, and met other young members of the Sahrawi diaspora, who like him were affected by the radicalism sweeping Moroccan universities in the early 1970s (heavily influenced by May 1968 in France). He was the first alumnus in the history of Moroccan universities on achieving a punctuation of 19 out of 20 in Constitutional law. He travelled to Europe for the only time in his life about this time, visiting Amsterdam in the Netherlands & Paris in France.
El-Ouali Mustapha Sayed was associated with Ila al-Amam, a clandestine Marxist group that took a position explicitly in favour of Sahrawi self-determination.
Polisario Front
El-Ouali grew increasingly disturbed by the oppressive Spanish colonial rule over what was then known as Spanish Sahara, and although never involved with the Harakat Tahrir, news |
https://en.wikipedia.org/wiki/Gallid%20alphaherpesvirus%203 | Gallid alphaherpesvirus 3 (GaHV-3) is a species of virus in the genus Mardivirus, subfamily Alphaherpesvirinae, family Herpesviridae, and order Herpesvirales. |
https://en.wikipedia.org/wiki/Microecosystem | Microecosystems can exist in locations which are precisely defined by critical environmental factors within small or tiny spaces.
Such factors may include temperature, pH, chemical milieu, nutrient supply, presence of symbionts or solid substrates, gaseous atmosphere (aerobic or anaerobic) etc.
Some examples
Pond microecosystems
These microecosystems with limited water volume are often only of temporary duration and hence colonized by organisms which possess a drought-resistant spore stage in the lifecycle, or by organisms which do not need to live in water continuously. The ecosystem conditions applying at a typical pond edge can be quite different from those further from shore. Extremely space-limited water ecosystems can be found in, for example, the water collected in bromeliad leaf bases and the "pitchers" of Nepenthes.
Animal gut microecosystems
These include the buccal region (especially cavities in the gingiva), rumen, caecum etc. of mammalian herbivores or even invertebrate digestive tracts. In the case of mammalian gastrointestinal microecology, microorganisms such as protozoa, bacteria, as well as curious incompletely defined organisms (such as certain large structurally complex Selenomonads, Quinella ovalis "Quin's Oval", Magnoovum eadii "Eadie's Oval", Oscillospira etc.) can exist in the rumen as incredibly complex, highly enriched mixed populations, (see Moir and Masson images ). This type of microecosystem can adjust rapidly to changes in the nutrition or health of the host animal (usually a ruminant such as cow, sheep, goat etc.); see Hungate's "The Rumen and its microbes 1966). Even within a small closed system such as the rumen there may exist a range of ecological conditions: Many organisms live freely in the rumen fluid whereas others require the substrate and metabolic products supplied by the stomach wall tissue with its folds and interstices. Interesting questions are also posed concerning the transfer of the strict anaerobe organisms in t |
https://en.wikipedia.org/wiki/Pseudo-spectral%20method | Pseudo-spectral methods, also known as discrete variable representation (DVR) methods, are a class of numerical methods used in applied mathematics and scientific computing for the solution of partial differential equations. They are closely related to spectral methods, but complement the basis by an additional pseudo-spectral basis, which allows representation of functions on a quadrature grid. This simplifies the evaluation of certain operators, and can considerably speed up the calculation when using fast algorithms such as the fast Fourier transform.
Motivation with a concrete example
Take the initial-value problem
with periodic conditions . This specific example is the Schrödinger equation for a particle in a potential , but the structure is more general. In many practical partial differential equations, one has a term that involves derivatives (such as a kinetic energy contribution), and a multiplication with a function (for example, a potential).
In the spectral method, the solution is expanded in a suitable set of basis functions, for example plane waves,
Insertion and equating identical coefficients yields a set of ordinary differential equations for the coefficients,
where the elements are calculated through the explicit Fourier-transform
The solution would then be obtained by truncating the expansion to basis functions, and finding a solution for the . In general, this is done by numerical methods, such as Runge–Kutta methods. For the numerical solutions, the right-hand side of the ordinary differential equation has to be evaluated repeatedly at different time steps. At this point, the spectral method has a major problem with the potential term .
In the spectral representation, the multiplication with the function transforms into a vector-matrix multiplication, which scales as . Also, the matrix elements need to be evaluated explicitly before the differential equation for the coefficients can be solved, which requires an additional step.
In |
https://en.wikipedia.org/wiki/Immune%20response | An immune response is a physiological reaction which occurs within an organism in the context of inflammation for the purpose of defending against exogenous factors. These include a wide variety of different toxins, viruses, intra- and extracellular bacteria, protozoa, helminths, and fungi which could cause serious problems to the health of the host organism if not cleared from the body.
In addition, there are other forms of immune response. For example, harmless exogenous factors (such as pollen and food components) can trigger allergy; latex and metals are also known allergens.
A transplanted tissue (for example, blood) or organ can cause graft-versus-host disease. A type of immune reactivity known as Rh disease can be observed in pregnant women. These special forms of immune response are classified as hypersensitivity. Another special form of immune response is antitumor immunity.
In general, there are two branches of the immune response, the innate and the adaptive, which work together to protect against pathogens. Both branches engage humoral and cellular components.
The innate branch—the body's first reaction to an invader—is known to be a non-specific and quick response to any sort of pathogen. Components of the innate immune response include physical barriers like the skin and mucous membranes, immune cells such as neutrophils, macrophages, and monocytes, and soluble factors including cytokines and complement. On the other hand, the adaptive branch is the body's immune response which is catered against specific antigens and thus, it takes longer to activate the components involved. The adaptive branch include cells such as dendritic cells, T cell, and B cells as well as antibodies—also known as immunoglobulins—which directly interact with antigen and are a very important component for a strong response against an invader.
The first contact that an organism has with a particular antigen will result in the production of effector T and B cells which are act |
https://en.wikipedia.org/wiki/Acibenzolar-S-methyl | Acibenzolar-S-methyl is the ISO common name for an organic compound that is used as a fungicide. Unusually, it is not directly toxic to fungi but works by inducing systemic acquired resistance, the natural defence system of plants.
History
In the 1980s, researchers at Ciba-Geigy in Switzerland were seeking novel fungicides. They discovered that the methyl ester of 1,2,3-benzothiadiazole-7-carboxylic acid, and many other derivatives, had useful activity on fungal diseases, for example Pyricularia oryzae on rice. In subsequent studies it was shown that the compound responsible for the biological activity was the carboxylic acid itself but that for optimum activity when used commercially it was important to choose a derivative which met requirements of product safety, ease of application and appropriate physical properties for translocation in the crop. After many derivatives of the acid had been tested, the S-methyl thioester was chosen for development under the code name CGA245704. The product was launched in 1996 and is now sold by Syngenta with brand names including Bion and Actigard.
Synthesis
The first synthesis of the parent 1,2,3-benzothiadiazole-7-carboxylic acid was disclosed in patents filed by Ciba-Geigy. The heterocyclic ring of the 1,2,3-benzothiadiazole core is formed by the classic ring-closure of a thiol onto a diazonium group adjacent in its benzene ring. One example from the patent is the diazotisation reaction of 3-amino-2-benzylthiobenzoic acid methyl ester, as its hydrochloride salt, with sodium nitrite in water. This gives 7-methoxycarbonyl-1,2,3-benzothiadiazole in 86% yield after recrystallization.
Conversion of the ester into the thioester is by standard hydrolysis to form the free carboxylic acid followed by conversion of the acid to the S-methyl thioester as standard chemical transformations.
Mechanism of action
Acibenzolar-S-methyl has an unusual mechanism of action for a fungicide. It is not directly toxic to the fungus but instead act |
https://en.wikipedia.org/wiki/Thallophyte | Thallophytes (Thallophyta, Thallophyto or Thallobionta) are a polyphyletic group of non-motile organisms traditionally described as "thalloid plants", "relatively simple plants" or "lower plants". They form a division of kingdom Plantae that include lichens and algae and occasionally bryophytes, bacteria and slime moulds. Thallophytes have a hidden reproductive system and hence they are also incorporated into the similar Cryptogamae category (together with ferns), as opposed to Phanerogamae. Thallophytes are defined by having undifferentiated bodies (thalloid, pseudotissue), as opposed to cormophytes (Cormophyta) with roots and stems. Various groups of thallophytes are major contributors to marine ecosystems.
Definitions
Several different definitions of the group have been used.
Thallophytes (Thallophyta or Thallobionta) are a polyphyletic group of non-mobile organisms traditionally described as "thalloid plants", "relatively simple plants" or "lower plants".
Stephan Endlicher, a 19th-century Austrian botanist, separated the vegetable kingdom into the thallophytes (algae, lichens, fungi) and the cormophytes (including bryophytes and thus being equivalent to Embryophyta in this case) in 1836. This definition of Thallophyta is approximately equivalent to Protophyta, which has always been a loosely defined group.
In the Lindley system (1830–1839), Endlicher's cormophytes were divided into the thallogens (including the bryophytes), and cormogens ("non-flowering" plants with roots), as well as the six other classes. Cormogens were a much smaller group than Endlicher's cormophytes, including just the ferns (and Equisetopsida) and the plants now known as lycopodiophytes.
Thallophyta is a division of the plant kingdom including primitive forms of plant life showing a simple plant body. Including unicellular to large algae, fungi, lichens.
The first ten phyla are referred to as thallophytes. They are simple plants without roots stems or leaves.
They are non-embryophy |
https://en.wikipedia.org/wiki/Regional%20Acceleratory%20Phenomenon | Regional acceleratory phenomenon (RAP) is a sudden acceleration of normal tissue processes in reaction to noxious stimuli. It has been exploited in treatments such as the healing of atrophic or oligotrophic nonunions and surgically facilitated orthodontic therapy.
Background
In the early 1980s, American orthopedist Harold Frost published a review article detailing then known experiences with regional acceleratory phenomena, which can be caused by injuries such as fractures and burns, afflictions such as acute paralysis and arthritis, bone movement such as implant placement and orthodontics, as well as vitamin D, thyroxine, and electrical stimuli. Once evoked, processes such as perfusion, the growth of skin, bone and other connective tissues, as well as their healing, turnover and remodeling can all accelerate beyond normal values. More overt manifestations include warmness of an affected region, decreased bone density, and increased bone plasticity. In rat tibia, more intense RAP was observed with deeper corticotomy. RAP typically lasts four months but, in cases of branchial plexus injuries or severe burns, potentially over two years and predisposing the patient to hypercalciuria and genitourinary tract lithiasis. If the causative stimuli were not removed, RAP may even persist indefinitely.
Effects
The effects of regional acceleratory phenomenon can be positive or negative. A study in rabbits suggested that, following osteotomy, RAP contributed to a fivefold increase in new bone without a change in bone volume. In tibial fractures, accelerated bone turnover allows the union of interfaces to occur typically within six months, compared to about twenty years for remodeling based on basic multicellular units (BMUs) alone. On the other hand, increased collagen production due to RAP in rheumatoid arthritis or osteoid osteoma may lead to diffuse fibrosis and joint stiffening.
Impaired RAP
Obtunded or absent RAP often accompanies sensory denervation. In neuropathic so |
https://en.wikipedia.org/wiki/Percolation%20test | A percolation test (colloquially called a perc test) is a test to determine the water absorption rate of soil (that is, its capacity for percolation) in preparation for the building of a septic drain field (leach field) or infiltration basin. The results of a percolation test are required to properly design a septic system. In its broadest terms, percolation testing is simply observing how quickly a known volume of water dissipates into the subsoil of a drilled hole of known surface area. While every jurisdiction will have its own laws regarding the exact calculations for the length of line, depth of pit, etc., the testing procedures are the same.
In general, sandy soil will absorb more water than soil with a high concentration of clay or where the water table is close to the surface.
Testing method
A percolation test consists of digging one or more holes in the soil of the proposed leach field to a specified depth, presoaking the holes by maintaining a high water level in the holes, then running the test by filling the holes to a specific level and timing the drop of the water level as the water percolates into the surrounding soil. There are various empirical formulae for determining the required size of a leach field based on the size of facility, the percolation test results, and other parameters.
For leach line testing, a minimum of three test holes are drilled or dug by hand, most commonly six to eight inches in diameter. Ideally, these should be drilled to different depths from three to six feet below the surface. For better, more conclusive results, five drill holes are used in a pattern of one hole at each corner of the proposed leach field and one test hole in the center. Testing of these holes will result in a value with units of minutes per inch. This value is then correlated to a predetermined county health code to establish the exact size of the leach field.
Testing for horizontal pits typically requires five to eight test holes drilled in a |
https://en.wikipedia.org/wiki/Effects%20of%20nicotine%20on%20human%20brain%20development | Exposure to nicotine, from conventional or electronic cigarettes during adolescence can impair the developing human brain. E-cigarette use is recognized as a substantial threat to adolescent behavioral health. The use of tobacco products, no matter what type, is almost always started and established during adolescence when the developing brain is most vulnerable to nicotine addiction. Young people's brains build synapses faster than adult brains. Because addiction is a form of learning, adolescents can get addicted more easily than adults. The nicotine in e-cigarettes can also prime the adolescent brain for addiction to other drugs such as cocaine. Exposure to nicotine and its great risk of developing an addiction, are areas of significant concern.
Nicotine is a parasympathomimetic stimulant that binds to and activates nicotinic acetylcholine receptors in the brain, which subsequently causes the release of dopamine and other neurotransmitters, such as norepinephrine, acetylcholine, serotonin, gamma-aminobutyric acid, glutamate and endorphins. Nicotine interferes with the blood–brain barrier function, and as a consequence raises the risk of brain edema and neuroinflammation. When nicotine enters the brain it stimulates, among other activities, the midbrain dopaminergic neurons situated in the ventral tegmental area and pars compacta.
Nicotine negatively affects the prefrontal cortex of the developing brain. Prenatal nicotine exposure can result in long-term adverse effects to the developing brain. Prenatal nicotine exposure has been associated with dysregulation of catecholaminergic, serotonergic, and other neurotransmitter systems. E-liquid exposure whether intentional or unintentional from ingestion, eye contact, or skin contact can cause adverse effects such as seizures and anoxic brain trauma. A study on the offspring of the pregnant mice, which were exposed to nicotine-containing e-liquid, showed significant behavioral alterations. This indicated that exposure |
https://en.wikipedia.org/wiki/Frederick%20John%20Jackson | Sir Frederick John Jackson, (17 February 1860 – 3 February 1929) was an English administrator, explorer and ornithologist.
Early years
Jackson was born at Oran Hall, near Catterick, North Yorkshire in 1860. He attended Shrewsbury School and then Jesus College, Cambridge.
In 1884 he went to Africa on a shooting trip, joining J. G. Haggard, the British consul at Lamu. On this trip he explored the coast of what is now Kenya, the Tana River and Mount Kilimanjaro. As well as shooting big game, he collected birds and butterflies. Soon after the 1886 treaty was signed to delimit the German and British spheres of influence in East Africa he joined the Imperial British East Africa Company (IBEAC).
Administrator
In 1889 Jackson led an IBEAC expedition that included his friend and fellow explorer Arthur Neumann in the party designed to open up the regions between Mombasa and Lake Victoria, which was largely unknown to Europeans at that time, and if possible to obtain news of Emin Pasha. At Kavirondo he received a letter from King Mwanga II of Buganda in Uganda describing a state of great confusion there owing to rivalry between different Christian factions. He went north, exploring the country beyond Mount Elgon. On his return to Kavirondo he found that the German Karl Peters had passed him and raised the German flag, which he pulled down. He went on to Uganda where he found the Baganda uncertain about whether to accept an IBEAC administration. The decision was made for them by the Heligoland treaty of 1900 in which Britain was given Uganda.
The British government took over the administration of British East Africa from IBEAC in 1894, and Jackson became an official. He was Lieutenant-Governor of the East African Protectorate (1907–1911) and Governor of Uganda (1911–1917).
He was appointed a Companion of the Order of the Bath (CB) for services during the mutiny of Sudanese troops in Uganda in 1898. For his administrative work he was appointed a Companion of the Order of |
https://en.wikipedia.org/wiki/Resilient%20control%20systems | In our modern society, computerized or digital control systems have been used to reliably automate many of the industrial operations that we take for granted, from the power plant to the automobiles we drive. However, the complexity of these systems and how the designers integrate them, the roles and responsibilities of the humans that interact with the systems, and the cyber security of these highly networked systems have led to a new paradigm in research philosophy for next-generation control systems. Resilient Control Systems consider all of these elements and those disciplines that contribute to a more effective design, such as cognitive psychology, computer science, and control engineering to develop interdisciplinary solutions. These solutions consider things such as how to tailor the control system operating displays to best enable the user to make an accurate and reproducible response, how to design in cybersecurity protections such that the system defends itself from attack by changing its behaviors, and how to better integrate widely distributed computer control systems to prevent cascading failures that result in disruptions to critical industrial operations. In the context of cyber-physical systems, resilient control systems are an aspect that focuses on the unique interdependencies of a control system, as compared to information technology computer systems and networks, due to its importance in operating our critical industrial operations.
Introduction
Originally intended to provide a more efficient mechanism for controlling industrial operations, the development of digital control systems allowed for flexibility in integrating distributed sensors and operating logic while maintaining a centralized interface for human monitoring and interaction. This ease of readily adding sensors and logic through software, which was once done with relays and isolated analog instruments, has led to wide acceptance and integration of these systems in all industries. Ho |
https://en.wikipedia.org/wiki/Oriane%20Lassus | Oriane Lassus (born in 1987) is a French author and cartoonist, as well as an illustrator.
Biography
Since 2009, Lassus has contributed to the Spongiculture blog in which she goes through her daily life against a backdrop of acerbic humour. The project won the "Blog Revelation Prize" two years later, at the Angoulême International Comics Festival.
After a master's degree in illustration at the Académie Royale des Beaux-Arts in Brussels, Lassus published her first comic book, (Vraoum, 2012). The book explores the individual micro-events that affect the family unit.
Lassus regularly participates in the artist residencies organized in Arc-et-Senans, which bring together each year a selection of authors among the most innovative of the alternative literary scene.
Since 2014, Lassus has collaborated with the children's magazine, , in which she publishes the story , honored in the youth selection of the Angoulême International Comics Festival 2018 and the subject of an exhibition in the Pavillon Jeunes Talents (young talents pavilion).
In 2016, the comic was published by Arbitraire. In it, Lassus highlights the situation of those women who choose not to have children.
Awards and honors
2011: Blog Revelation Prize for Spongiculture, Angoulême International Comics Festival
2020: (EESI) prize
Expositions
"Le Meilleurissime Repaire de la Terre", Festival d'Angoulême 2018, Pavillon Jeunes Talents, January 2018
"Oriane Lassus : Lauréate du Prix de l’ÉESI 2020, Exposition personnelle", Éesi Angoulême, 30 January to 15 February 2020
Selected works
Ça va derrière?, Vraoum, 2012
Immobilerie Pointure, Super Structure, 2013
Quoi de plus normal qu'infliger la vie?, Arbitraire, 2016
Première fraîcheur, Arbitraire, 2017
Le Meilleurissime Repaire de la Terre, Biscoto, 2017
Les Gardiennes du grenier, Biscoto, 2020 |
https://en.wikipedia.org/wiki/Biogenesis%20of%20lysosome-related%20organelles%20complex%201 | BLOC-1 or biogenesis of lysosome-related organelles complex 1 is a ubiquitously expressed multisubunit protein complex in a group of complexes that also includes BLOC-2 and BLOC-3. BLOC-1 is required for normal biogenesis of specialized organelles of the endosomal-lysosomal system, such as melanosomes and platelet dense granules. These organelles are called LROs (lysosome-related organelles) which are apparent in specific cell-types, such as melanocytes. The importance of BLOC-1 in membrane trafficking appears to extend beyond such LROs, as it has demonstrated roles in normal protein-sorting, normal membrane biogenesis, as well as vesicular trafficking. Thus, BLOC-1 is multi-purposed, with adaptable function depending on both organism and cell-type.
Mutations in all BLOC complexes lead to diseased states characterized by Hermansky-Pudlak Syndrome (HPS), a pigmentation disorder subdivided into multiple types depending on the mutation, highlighting the role of BLOC-1 in proper LRO-function. BLOC-1 mutations also are thought to be linked to schizophrenia, and BLOC-1 dysfunction in the brain has important ramifications in neurotransmission. Much effort has been given to uncovering the molecular mechanisms of BLOC-1 function to understand its role in these diseases.
Ultracentrifugation coupled with electron microscopy demonstrated that BLOC-1 has 8 subunits (pallidin, cappuccino, dysbindin, Snapin, Muted, BLOS1, BLOS2, and BLOS3) that are linked linearly to form a complex of roughly 300 Angstrom in length and 30 Angstrom in diameter. Bacterial recombination also demonstrated heterotrimeric subcomplexes containing pallidin, cappucinno, and BLOS1 as well as dysbindin, Snapin, and BLOS-2 as important intermediate structures. These subcomplexes may explain different functional outcomes observed by altering different BLOC-1 subunits. Furthermore, dynamic bending of the complex as much as 45 degrees indicates flexibility is likely linked to proper BLOC-1 function.
Within th |
https://en.wikipedia.org/wiki/Autonomous%20system%20%28Internet%29 | An autonomous system (AS) is a collection of connected Internet Protocol (IP) routing prefixes under the control of one or more network operators on behalf of a single administrative entity or domain, that presents a common and clearly defined routing policy to the Internet. Each AS is assigned an autonomous system number (ASN), for use in Border Gateway Protocol (BGP) routing. Autonomous System Numbers are assigned to Local Internet Registries (LIRs) and end user organizations by their respective Regional Internet Registries (RIRs), which in turn receive blocks of ASNs for reassignment from the Internet Assigned Numbers Authority (IANA). The IANA also maintains a registry of ASNs which are reserved for private use (and should therefore not be announced to the global Internet).
Originally, the definition required control by a single entity, typically an Internet service provider (ISP) or a very large organization with independent connections to multiple networks, that adhered to a single and clearly defined routing policy. In March 1996, the newer definition came into use because multiple organizations can run BGP using private AS numbers to an ISP that connects all those organizations to the Internet. Even though there may be multiple autonomous systems supported by the ISP, the Internet only sees the routing policy of the ISP. That ISP must have an officially registered ASN.
Until 2007, AS numbers were defined as 16-bit integers, which allowed for a maximum of 65,536 assignments. Since then, the IANA has begun to also assign 32-bit AS numbers to regional Internet registries (RIRs). These numbers are written preferably as simple integers, in a notation referred to as "asplain", ranging from 0 to 4,294,967,295 (hexadecimal 0xFFFF FFFF). Or, alternatively, in the form called "asdot+" which looks like x.y, where x and y are 16-bit numbers. Numbers of the form 0.y are exactly the old 16-bit AS numbers. The special 16-bit ASN 23456 ("AS_TRANS") was assigned by IANA as |
https://en.wikipedia.org/wiki/The%20Right%20to%20Read | The Right to Read is a short story by Richard Stallman, the founder of the Free Software Foundation, which was first published in 1997 in Communications of the ACM. It is a cautionary tale set in the year 2047, when DRM-like technologies are employed to restrict the readership of books; when the sharing of books and written material is a crime punishable by imprisonment.
In particular, the story touches on the impact of such a system on university students, due to their need for materials, one (Dan Halbert) of whom is forced into a dilemma in which he must decide whether to loan his computer to a fellow student (Lissa Lenz), who would then have the ability to illegally access his purchased documents.
It is notable for being written before the use of Digital Rights Management (DRM) technology was widespread (although DVD video discs which used DRM had appeared the year before, and various proprietary software since the 1970s had made use of some form of copy protection), and for predicting later hardware-based attempts to restrict how users could use content, such as Trusted Computing.
See also
The Digital Imprimatur
External links
The Right to Read
Free content
Digital rights management
Free software
1997 short stories |
https://en.wikipedia.org/wiki/Turing%20test | The Turing test, originally called the imitation game by Alan Turing in 1950, is a test of a machine's ability to exhibit intelligent behaviour equivalent to, or indistinguishable from, that of a human. Turing proposed that a human evaluator would judge natural language conversations between a human and a machine designed to generate human-like responses. The evaluator would be aware that one of the two partners in conversation was a machine, and all participants would be separated from one another. The conversation would be limited to a text-only channel, such as a computer keyboard and screen, so the result would not depend on the machine's ability to render words as speech. If the evaluator could not reliably tell the machine from the human, the machine would be said to have passed the test. The test results would not depend on the machine's ability to give correct answers to questions, only on how closely its answers resembled those a human would give. Since the Turing test is a test of indistinguishability in performance capacity, the verbal version generalizes naturally to all of human performance capacity, verbal as well as nonverbal (robotic).
The test was introduced by Turing in his 1950 paper "Computing Machinery and Intelligence" while working at the University of Manchester. It opens with the words: "I propose to consider the question, 'Can machines think? Because "thinking" is difficult to define, Turing chooses to "replace the question by another, which is closely related to it and is expressed in relatively unambiguous words." Turing describes the new form of the problem in terms of a three-person game called the "imitation game", in which an interrogator asks questions of a man and a woman in another room in order to determine the correct sex of the two players. Turing's new question is: "Are there imaginable digital computers which would do well in the imitation game?" This question, Turing believed, was one that could actually be answered. In the |
https://en.wikipedia.org/wiki/Taraxacum%20officinale | Taraxacum officinale, the dandelion or common dandelion, is a herbaceous perennial flowering plant in the daisy family Asteraceae (syn. Compositae). The common dandelion is well known for its yellow flower heads that turn into round balls of many silver-tufted fruits that disperse in the wind. These balls are called "clocks" in both British and American English. The name "blowball" is also used.
The common dandelion grows in temperate regions of the world in areas with moist soils. They are very hardy plants, able to grow in a variety of environments, and are tolerant of crowding, extremes of temperature, and low moisture. As a result of this hardiness, in addition to its ability to rapidly propagate itself, the dandelion has become established over a wide range via human activity, originally being native to Eurasia, but can also be found across the Americas, southern Africa, India, Australia and New Zealand as a result of incidental or deliberate introductions.
It is most often considered a weed, especially in lawns and along roadsides, but the leaves, flowers, and roots are sometimes used in herbal medicine and as food.
Description
Taraxacum officinale grows from (generally unbranched) taproots and produces several hollow, leafless flower stems that are typically tall, but sometimes up to tall. The stems can be tinted purplish, they are upright or lax, and produce flower heads that are held as tall or taller than the foliage. The foliage may be upright-growing or horizontally spreading; the leaves have petioles that are either unwinged or narrowly winged. The stems can be glabrous or sparsely covered with short hairs. Plants have milky latex and the leaves are all basal; each flowering stem lacks bracts and has one single flower head. The yellow flower heads lack receptacle bracts and all the flowers, which are called florets, are ligulate and bisexual. In many lineages, fruits are mostly produced by apomixis, notwithstanding the flowers are visited by many |
https://en.wikipedia.org/wiki/Pl%C3%BCcker%20matrix | The Plücker matrix is a special skew-symmetric 4 × 4 matrix, which characterizes a straight line in projective space. The matrix is defined by 6 Plücker coordinates with 4 degrees of freedom. It is named after the German mathematician Julius Plücker.
Definition
A straight line in space is defined by two distinct points and in homogeneous coordinates of the projective space. Its Plücker matrix is:
Where the skew-symmetric -matrix is defined by the 6 Plücker coordinates
with
Plücker coordinates fulfill the Grassmann–Plücker relations
and are defined up to scale. A Plücker matrix has only rank 2 and four degrees of freedom (just like lines in ). They are independent of a particular choice of the points and and can be seen as a generalization of the line equation i.e. of the cross product for both the intersection (meet) of two lines, as well as the joining line of two points in the projective plane.
Properties
The Plücker matrix allows us to express the following geometric operations as matrix-vector product:
Plane contains line:
is the point of intersection of the line and the plane ('Meet')
Point lies on line:
is the common plane , which contains both the point and the line ('Join').
Direction of a line: (Note: The latter can be interpreted as a plane orthogonal to the line passing through the coordinate origin)
Closest point to the origin
Uniqueness
Two arbitrary distinct points on the line can be written as a linear combination of and :
Their Plücker matrix is thus:
up to scale identical to .
Intersection with a plane
Let denote the plane with the equation
which does not contain the line . Then, the matrix-vector product with the Plücker matrix describes a point
which lies on the line because it is a linear combination of and . is also contained in the plane
and must therefore be their point of intersection.
In addition, the product of the Plücker matrix with a plane is the zero-vector, exactly if the line is contain |
https://en.wikipedia.org/wiki/William%20Gelbart | William Michael Gelbart (born June 12, 1946) is Distinguished Professor of Chemistry and Biochemistry at the University of California, Los Angeles, and a member of the California NanoSystems Institute and the UCLA Molecular Biology Institute. He obtained his Bachelor of Science degree from Harvard University in 1967, his Master's (1968) and PhD (1970) degrees from the University of Chicago, and did postdoctoral work at the University of Paris (1971) and the University of California, Berkeley (1972). After 30 years of research in theoretical physical chemistry, contributing notably to the fields of gas-phase photophysics, optical properties of simple liquids, and the statistical physics of complex fluids, he started a biophysics laboratory with Charles Knobler in 2002 to investigate the physical aspects of viral infectivity.
Education and career
Gelbart's early interest in science was inspired by his time as an undergraduate researcher in the molecular spectroscopy group of William Klemperer at Harvard. As a graduate student at the University of Chicago, with his mentors Stuart A. Rice, Karl Freed, and Joshua Jortner, he developed the modern theory of non-radiative processes ("radiationless transitions") in molecular photophysics. He was a US National Science Foundation/NATO Postdoctoral Fellow at the, University of Paris in 1971, and a Miller Institute Postdoctoral Fellow at UC Berkeley in 1972, during which time he switched fields and formulated a general theory of collision-induced optical properties of simple fluids.
He was appointed Assistant Professor of Chemistry, at UC Berkeley in 1972, continuing his researches on the quantum mechanical theory of molecular spectroscopy and on the statistical mechanical theory of intermolecular and multiple light scattering in liquids away from and near their critical points. He moved to UCLA as Associate Professor of Chemistry in 1975, and was promoted to full Professor in 1979 and to Distinguished Professor in 1999. H |
https://en.wikipedia.org/wiki/Space%20diagonal | In geometry, a space diagonal (also interior diagonal or body diagonal) of a polyhedron is a line connecting two vertices that are not on the same face. Space diagonals contrast with face diagonals, which connect vertices on the same face (but not on the same edge) as each other.
For example, a pyramid has no space diagonals, while a cube (shown at right) or more generally a parallelepiped has four space diagonals.
Axial diagonal
An axial diagonal is a space diagonal that passes through the center of a polyhedron.
For example, in a cube with edge length a, all four space diagonals are axial diagonals, of common length More generally, a cuboid with edge lengths a, b, and c has all four space diagonals axial, with common length
A regular octahedron has 3 axial diagonals, of length , with edge length a.
A regular icosahedron has 6 axial diagonals of length , where is the golden ratio .
Space diagonals of magic cubes
A magic square is an arrangement of numbers in a square grid so that the sum of the numbers along every row, column, and diagonal is the same. Similarly, one may define a magic cube to be an arrangement of numbers in a cubical grid so that the sum of the numbers on the four space diagonals must be the same as the sum of the numbers in each row, each column, and each pillar.
See also
Distance
Face diagonal
Magic cube classes
Hypotenuse
Spacetime interval |
https://en.wikipedia.org/wiki/High%20contrast%20grating | In physics, a high contrast grating is a single layer near-wavelength grating physical structure where the grating material has a large contrast in index of refraction with its surroundings. The term near-wavelength refers to the grating period, which has a value between one optical wavelength in the grating material and that in its surrounding materials.
The high contrast gratings have many distinct attributes that are not found in conventional gratings. These features include broadband ultra-high reflectivity, broadband ultra-high transmission, and very high quality factor resonance, for optical beam surface-normal or in oblique incidence to the grating surface. The high reflectivity grating can be ultrathin, only <0.15 optical wavelength. The reflection and transmission phase of the optical beam through the high contrast grating can be engineered to cover a full 2π range while maintaining a high reflection or transmission coefficient.
History
The concept of high contrast grating took off with a report on a broadband high reflectivity reflector for surface-normal incident light (the ratio between the wavelength bandwidth with a reflectivity larger than 0.99 and the central wavelength is greater than 30%) in 2004 by Constance J. Chang-Hasnain et al., which was demonstrated experimentally in the same year. The key idea is to have the high-refractive-index material all surrounded by low-refractive-index material. They are subsequently applied as a highly reflective mirror in vertical-cavity surface-emitting lasers, as well as monolithic, continuously wavelength tunable vertical-cavity surface-emitting lasers. The properties of high contrast grating are rapidly explored since then. The following lists some relevant examples:
In 2008, a single layer of high contrast grating was demonstrated as a high quality factor cavity.
In 2009, hollow-core waveguides using high contrast grating were proposed, followed by experimentally demonstration in 2012. This experiment |
https://en.wikipedia.org/wiki/Residue%20theorem | In complex analysis, the residue theorem, sometimes called Cauchy's residue theorem, is a powerful tool to evaluate line integrals of analytic functions over closed curves; it can often be used to compute real integrals and infinite series as well. It generalizes the Cauchy integral theorem and Cauchy's integral formula. The residue theorem should not be confused with special cases of the generalized Stokes' theorem; however, the latter can be used as an ingredient of its proof.
Statement
The statement is as follows:
Let be a simply connected open subset of the complex plane containing a finite list of points and a function holomorphic on Letting be a closed rectifiable curve in and denoting the residue of at each point by and the winding number of around by the line integral of around is equal to times the sum of residues, each counted as many times as winds around the respective point:
If is a positively oriented simple closed curve, is if is in the interior of and if not, therefore
with the sum over those inside
The relationship of the residue theorem to Stokes' theorem is given by the Jordan curve theorem. The general plane curve must first be reduced to a set of simple closed curves whose total is equivalent to for integration purposes; this reduces the problem to finding the integral of along a Jordan curve with interior The requirement that be holomorphic on is equivalent to the statement that the exterior derivative on Thus if two planar regions and of enclose the same subset of the regions and lie entirely in hence
is well-defined and equal to zero. Consequently, the contour integral of along is equal to the sum of a set of integrals along paths each enclosing an arbitrarily small region around a single — the residues of (up to the conventional factor at Summing over we recover the final expression of the contour integral in terms of the winding numbers
In order to evaluate real integrals, the re |
https://en.wikipedia.org/wiki/Gamma%20secretase | Gamma secretase is a multi-subunit protease complex, itself an integral membrane protein, that cleaves single-pass transmembrane proteins at residues within the transmembrane domain. Proteases of this type are known as intramembrane proteases. The most well-known substrate of gamma secretase is amyloid precursor protein, a large integral membrane protein that, when cleaved by both gamma and beta secretase, produces a short 37-43 amino acid peptide called amyloid beta whose abnormally folded fibrillar form is the primary component of amyloid plaques found in the brains of Alzheimer's disease patients. Gamma secretase is also critical in the related processing of several other type I integral membrane proteins, such as Notch, ErbB4, E-cadherin, N-cadherin, ephrin-B2, or CD44.
Subunits and assembly
The gamma secretase complex consists of four individual proteins: PSEN1 (presenilin-1), nicastrin, APH-1 (anterior pharynx-defective 1), and PEN-2 (presenilin enhancer 2). Recent evidence suggests that a fifth protein, known as CD147, is a non-essential regulator of the complex whose absence increases activity. Presenilin, an aspartyl protease, is the catalytic subunit; mutations in the presenilin gene have been shown to be a major genetic risk factor for Alzheimer's disease and modulates immune cell activity. In humans, two forms of presenilin and two forms of APH-1 have been identified in the genome; one of the APH homologs can also be expressed in two isoforms via alternative splicing, leading to at least six different possible gamma secretase complexes that may have tissue- or cell type specificity.
The proteins in the gamma secretase complex are heavily modified by proteolysis during assembly and maturation of the complex; a required activation step is in the autocatalytic cleavage of presenilin to N- and C-terminal fragments. Nicastrin's primary role is in maintaining the stability of the assembled complex and regulating intracellular protein trafficking. PEN-2 asso |
https://en.wikipedia.org/wiki/Xv6 | xv6 is a modern reimplementation of Sixth Edition Unix in ANSI C for multiprocessor x86 and RISC-V systems. It was created for pedagogical purposes in MIT's Operating System Engineering course in 2006.
Purpose
MIT's Operating System Engineering course formerly used the original V6 source code. xv6 was created as a modern replacement, because PDP-11 machines are not widely available and the original operating system was written in archaic pre-ANSI C. Unlike Linux or BSD, xv6 is simple enough to cover in a semester, yet still contains the important concepts and organization of Unix.
Self-documentation
One feature of the Makefile for xv6 is the option to produce a PDF of the entire source code listing in a readable format. The entire printout is only 99 pages, including cross references. This is reminiscent of the original V6 source code, which was published in a similar form in Lions' Commentary on UNIX 6th Edition, with Source Code.
Educational use
xv6 has been used in operating systems courses at many universities, including:
Ben-Gurion University
Binghamton University
CentraleSupélec
Columbia University
Ghulam Ishaq Khan Institute
Federico Santa María Technical University
George Washington University
Georgia Tech
IIIT Allahabad
IIT Bhubaneswar and PEC Chandigarh
IIT Bombay
IIT Delhi
IIT Madras
IIIT Delhi
IIIT Bangalore
IIIT Hyderabad
Iran University of Science and Technology
Johns Hopkins University
Karlsruhe Institute of Technology
Linnaeus University
Milwaukee School of Engineering
Motilal Nehru National Institute of Technology Allahabad
National Taiwan University
National University of Córdoba
National University of Río Cuarto
New York University
Northeastern University
Northwestern University
Portland State University
Rutgers University
Slovak University of Technology in Bratislava
Southern Adventist University
Stony Brook University
Technion – Israel Institute of Technology
Tsinghua University
Federal University of Mina |
https://en.wikipedia.org/wiki/Galileo%20GDS | Galileo is a computer reservations system (CRS) owned by Travelport. As of 2000, it had a 26.4% share of worldwide CRS airline bookings.
In addition to airline reservations, the Galileo CRS is also used to book train travel, cruises, car rental, and hotel rooms.
The Galileo system was moved from Denver, Colorado, to the Worldspan datacenter in Atlanta, Georgia, on September 28, 2008, following the 2007 merger of Travelport and Worldspan (although they now share the same datacenter, they continue to be run as separate systems).
Galileo is subject to the Capps II and its successor Secure Flight program for the selection of passengers with a risk profile.
Galileo is a member of the International Air Transport Association, of the OpenTravel Alliance and of SITA.
History
Galileo traces its roots back to 1971 when United Airlines created its first computerized central reservation system under the name Apollo. During the 1980s and early 1990s, a significant proportion of airline tickets were sold by travel agents. Flights by the airline owning the reservation system had preferential display on the computer screen. Due to the high market penetration of the Sabre and Apollo systems, owned by American Airlines and United Airlines, respectively, Worldspan and Galileo were created by other airline groups in an attempt to gain market share in the computer reservation system market and, by inference, the commercial airline market. Galileo was formed in 1987 by nine European carriers -- British Airways, KLM Royal Dutch Airlines, Alitalia, Swissair, Austrian Airlines, Olympic, Sabena, Air Portugal and Aer Lingus.
In response and to prevent possible government intervention, United Airlines spun off its Apollo reservation system, which was then controlled by Covia. Galileo International was born when Covia acquired Europe's Galileo and merged it with the Apollo system in 1992.
The Apollo reservation system was used by United Airlines until 3 March 2012, when it switched t |
https://en.wikipedia.org/wiki/Utility%20computing | Utility computing, or computer utility, is a service provisioning model in which a service provider makes computing resources and infrastructure management available to the customer as needed, and charges them for specific usage rather than a flat rate. Like other types of on-demand computing (such as grid computing), the utility model seeks to maximize the efficient use of resources and/or minimize associated costs. Utility is the packaging of system resources, such as computation, storage and services, as a metered service. This model has the advantage of a low or no initial cost to acquire computer resources; instead, resources are essentially rented.
This repackaging of computing services became the foundation of the shift to "on demand" computing, software as a service and cloud computing models that further propagated the idea of computing, application and network as a service.
There was some initial skepticism about such a significant shift. However, the new model of computing caught on and eventually became mainstream.
IBM, HP and Microsoft were early leaders in the new field of utility computing, with their business units and researchers working on the architecture, payment and development challenges of the new computing model. Google, Amazon and others started to take the lead in 2008, as they established their own utility services for computing, storage and applications.
Utility computing can support grid computing which has the characteristic of very large computations or sudden peaks in demand which are supported via a large number of computers.
"Utility computing" has usually envisioned some form of virtualization so that the amount of storage or computing power available is considerably larger than that of a single time-sharing computer. Multiple servers are used on the "back end" to make this possible. These might be a dedicated computer cluster specifically built for the purpose of being rented out, or even an under-utilized supercomputer. |
https://en.wikipedia.org/wiki/Core%20FTP | Core FTP LE is a freeware secure FTP client for Windows, developed by CoreFTP.com. Features include FTP, SSL/TLS, SFTP via SSH, and HTTP/HTTPS support. Secure FTP clients encrypt account information and data transferred across the internet, protecting data from being seen, or sniffed across networks. Core FTP is a traditional FTP client with local files displayed on the left, remote files on the right.
Core FTP Server is a secure FTP server for Windows, developed by CoreFTP.com, starting in 2010.
Licensing
CoreFTP LE is free for personal, educational, non-profit, and business use.
See also
Comparison of FTP client software
List of FTP server software
Reviews and references
PC Magazine – 59 Ways to Supercharge Windows – Odds & Ends – Core FTP LE
Softpedia.com – Reviews – "Today, try Core FTP Lite!" – By: Codrut Nistor, Editor, Software Reviews |
https://en.wikipedia.org/wiki/Moodies%20Group | The Moodies Group is a geological formation in South Africa and Eswatini. It has the oldest well-preserved siliciclastic tidal deposits on Earth, where microbial mats flourished.
See also
Archean life in the Barberton Greenstone Belt
Fig Tree Formation
Onverwacht Group |
https://en.wikipedia.org/wiki/Bryology | Bryology (from Greek , a moss, a liverwort) is the branch of botany concerned with the scientific study of bryophytes (mosses, liverworts, and hornworts). Bryologists are people who have an active interest in observing, recording, classifying or researching bryophytes. The field is often studied along with lichenology due to the similar appearance and ecological niche of the two organisms, even though bryophytes and lichens are not classified in the same kingdom.
History
Bryophytes were first studied in detail in the 18th century. The German botanist Johann Jacob Dillenius (1687–1747) was a professor at Oxford and in 1717 produced the work "Reproduction of the ferns and mosses." The beginning of bryology really belongs to the work of Johannes Hedwig, who clarified the reproductive system of mosses (1792, Fundamentum historiae naturalist muscorum) and arranged a taxonomy.
Research
Areas of research include bryophyte taxonomy, bryophytes as bioindicators, DNA sequencing, and the interdependency of bryophytes and other plant, fungal and animal species. Among other things, scientists have discovered parasitic (mycoheterotrophic) bryophytes such as Aneura mirabilis (previously known as Cryptothallus mirabilis) and potentially carnivorous liverworts such as Colura zoophaga and Pleurozia.
Centers of research in bryology include the University of Bonn in Germany, the University of Helsinki in Finland and the New York Botanical Garden.
Journals
The Bryologist a scientific journal began publication in 1898, and includes articles on all aspects of the biology of mosses, hornworts, liverworts and lichens and also book reviews. It is published by The American Bryological and Lichenological Society.
The scientific Journal of Bryology, renamed in 1972 from its original name of Transactions of the British Bryological Society that commenced in 1947, is published by the British Bryological Society.
Notable bryologists
Miles Joseph Berkeley (1803–1889)
Elizabeth Gertrude Bri |
https://en.wikipedia.org/wiki/Self-buckling | A column can buckle due to its own weight with no other direct forces acting on it, in a failure mode called self-buckling. In conventional column buckling problems, the self-weight is often neglected since it is assumed to be small when compared to the applied axial loads. However, when this assumption is not valid, it is important to take the self-buckling into account.
Elastic buckling of a "heavy" column i.e., column buckling under its own weight, was first investigated by Greenhill at 1881. He found that a free-standing, vertical column, with density , Young's modulus , and cross-sectional area , will buckle under its own weight if its height exceeds a certain critical value:
where is the acceleration due to gravity, is the second moment of area of the beam cross section.
One interesting example for the use of the equation was suggested by Greenhill in his paper. He estimated the maximal height of a pine tree, and found it cannot grow over 300-ft tall. This length sets the maximum height for trees on earth if we assume the trees to be prismatic and the branches are neglected.
Mathematical derivation
Suppose a uniform column fixed in a vertical direction at its lowest point, and carried to a height , in which the vertical position becomes unstable and flexure begins. There is a body force per unit length , where is the cross-sectional area of the column, is the acceleration due to gravity and is its mass density.
The column is slightly curved under its own weight, so the curve describes the deflection of the beam in the direction at some position . Looking at any point on the column, we can write the moment equilibrium:
where the right-hand side of the equation is the moment of the weight of BP about P.
According to Euler–Bernoulli beam theory:
Where is the Young's modulus of elasticity of the substance, is the second moment of area.
Therefore, the differential equation of the central line of BP is:
Differentiating with respect to x |
https://en.wikipedia.org/wiki/Video%20post-processing | The term post-processing (or postproc for short) is used in the video/film business for quality-improvement image processing (specifically digital image processing) methods used in video playback devices, such as stand-alone DVD-Video players; video playing software; and transcoding software. It is also commonly used in real-time 3D rendering (such as in video games) to add additional effects.
Uses in video production
Video post-processing is the process of changing the perceived quality of a video on playback (done after the decoding process). Image scaling routines such as linear interpolation, bilinear interpolation, or cubic interpolation can for example be performed when increasing the size of images; this involves either subsampling (reducing or shrinking an image) or zooming (enlarging an image). This helps reduce or hide image artifacts and flaws in the original film material. It is important to understand that post-processing always involves a trade-off between speed, smoothness and sharpness.
Image scaling and multivariate interpolation:
Nearest-neighbor interpolation
linear interpolation
bilinear interpolation
cubic interpolation
bicubic interpolation
Bézier surface
Lanczos resampling
trilinear interpolation
Tricubic interpolation
SPP (Statistical-Post-Processing)
Deblocking
Deringing
Sharpen / Unsharpen (often referred to as "soften")
Requantization
Luminance alterations
Blurring / denoising
Deinterlacing
weave deinterlace method
bob deinterlace method
linear deinterlace method
yadif deinterlace method
Deflicking
2:3 pull-down / ivtc (inverse telecine) for conversion from 24 frames/s and 23.976 frames/s to 30 frames/s and 29.97 frames/s
3:2 pull-up (telecine conversion) for conversion from 30 frames/s and 29.97 frames/s to 24 frames/s and 23.976 frames/s
Uses in 3D rendering
Additionally, post-processing is commonly used in 3D rendering, especially for video games. Instead of rendering 3D objects directly to the display, the |
https://en.wikipedia.org/wiki/Anton%20Felkel | Anton Felkel (26 April 1740, Kamenz, Silesia – c. 1800, possibly in Lisbon, Portugal) was an Austrian mathematician who worked on the determination of prime numbers.
Work
In 1776 and 1777, Felkel published a table giving complete decompositions of all integers not divisible by 2, 3, and 5, from 1 to 408,000. Felkel had planned to extend his table to 10 million. A reconstruction of his table is found on the LOCOMAT site.
Publications
Tafel aller einfachen Factoren der durch 2, 3, 5 nicht theilbaren Zahlen von 1 bis 10 000 000. Vienna: 1776;
I. Theil enthaltend die Factoren von 1 bis 144000 (also published in Latin)
Pars II. exhibens factores numerorum ab 144001 usque 336000
Pars III. exhibens factores numerorum ab 336001 usque 408000
Wahre Beschaffenheit des Donners: Eine ganz neue Entdeckung durch einen Liebhaber der Naturkunde. Wien: v. Ghelen, 1780;
Neueröffnetes Geheimniss der Parallellinien enthaltend verschiedene wichtige Zusätze zur Proportion und Körperlehre von Anton Felkel; nebst einer dreyfachen vorläufigen Nachricht von den dazu dienenden neuerfundenen mechanischen Kunstgriffen etc. Wien; von Ghelenschen Buchhandlung, 1781; |
https://en.wikipedia.org/wiki/Unistochastic%20matrix | In mathematics, a unistochastic matrix (also called unitary-stochastic) is a doubly stochastic matrix whose entries are the squares of the absolute values of the entries of some unitary matrix.
A square matrix B of size n is doubly stochastic (or bistochastic) if all its entries are non-negative real numbers and each of its rows and columns sum to 1. It is unistochastic if there exists a unitary matrix U such that
This definition is analogous to that for an orthostochastic matrix, which is a doubly stochastic matrix whose entries are the squares of the entries in some orthogonal matrix. Since all orthogonal matrices are necessarily unitary matrices, all orthostochastic matrices are also unistochastic. The converse, however, is not true. First, all 2-by-2 doubly stochastic matrices are both unistochastic and orthostochastic, but for larger n this is not the case. For example, take and consider the following doubly stochastic matrix:
This matrix is not unistochastic, since any two vectors with moduli equal to the square root of the entries of two columns (or rows) of B cannot be made orthogonal by a suitable choice of phases. For , the set of orthostochastic matrices is a proper subset of the set of unistochastic matrices.
the set of unistochastic matrices contains all permutation matrices and its convex hull is the Birkhoff polytope of all doubly stochastic matrices
for this set is not convex
for the set of triangle inequality on the moduli of the raw is a sufficient and necessary condition for the unistocasticity
for the set of unistochastic matrices takes the form of a centrosymmetric matrix and unistochasticity of any bistochastic matrix B is implied by a non-negative value of its Jarlskog invariant
for the relative volume of the set of unistochastic matrices with respect to the Birkhoff polytope of doubly stochastic matrices is
for explicit conditions for unistochasticity are not known yet, but there exists a numerical method to verify un |
https://en.wikipedia.org/wiki/Metview | Metview is a meteorological workstation and batch system developed at the European Centre for Medium-Range Weather Forecasts.
History
Developments were started at ECMWF in 1990 in co-operation with the National Institute for Space Research of Brazil and Météo-France.
Features
User interface
Metview has an icon based user interface, where any aspect of a meteorological (graphical) product is expressed in an icon. Users can prototype visualisation by dragging and dropping icons in the plot area.
Metview offers also various tools to explore and display the content of meteorological file formats, such as GRIB, BUFR, NetCDF and ODB.
Metview Macro language for batch processing
The Macro language is designed to be high level to allow analysts and scientist to concentrate on the work/processing flow they try to achieve.
# Metview Macro
# reading GRIB files through the read() function
a = read(mygrib1.grb)
b = read(mygrib2.grb)
# calculating the differences between two fields
c = a-b
# plotting the result
plot(c)
In 2017 a Python version of the macro language was developed.
Supported file formats
Metview supports the various meteorological data formats as input and output formats: GRIB (editions 1 and 2), BUFR, NetCDF, ODB (ECMWF Observation Database), Local databases and ASCII data files (Comma-separated values, grids and scattered data)
Development
All major developments are made at the Development Section at ECMWF. Most of the code is in C++ and the code is versioned in git. CMake is used as build system.
Metview makes use of other software packages developed at ECMWF. In fact Metview is an extended MARS client and uses ecCodes for GRIB and BUFR handling and Magics for contouring and visualisation.
Distribution
Metview is mainly distributed as a source tarball under the Apache License version 2.0. There are plans to distribute the code on GitHub.
Binary versions of Metview are available in conda (through the conda-forge channel), in Ubuntu and MacPo |
https://en.wikipedia.org/wiki/Victor%20Horsley | Sir Victor Alexander Haden Horsley (14 April 1857 – 16 July 1916) was a British scientist and professor.
He was born in Kensington, London. Educated at Cranbrook School, Kent, he studied medicine at University College London and in Berlin, Germany (1881) and, in the same year, started his career as a house surgeon and registrar at the University College Hospital. From 1884 to 1890, Horsley was Professor-Superintendent of the Brown Institute.
In 1886, he was appointed as Assistant Professor of Surgery at the National Hospital for Paralysis and Epilepsy, and as a Professor of Pathology (1887–1896) and Professor of Clinical Surgery (1899–1902) at University College London. He was a supporter of women's suffrage and was an opponent of tobacco and alcohol.
Personal life
Victor Alexander Haden Horsley was born in Kensington, London, the son of Rosamund (Haden) and John Callcott Horsley, R.A. His given name, Victor Alexander, was given to him by Queen Victoria.
In 1883, he became engaged to Eldred Bramwell, daughter of Sir Frederick Bramwell. On 4 October 1887, Victor and Eldred married at St. Margaret's, Westminster. They had two sons, Siward and Oswald, and a daughter, Pamela.
He was knighted in the 1902 Coronation Honours, receiving the accolade from King Edward VII at Buckingham Palace on 24 October that year.
Horsley was a champion of many causes. One of his primary life crusades was the temperance movement. Having observed that many injuries admitted to the hospital were due to alcohol, Horsley threw himself into becoming a temperance reformer. He soon rose up to the position of vice president of the National Temperance League and the president of the British Medical Temperance Association. In 1907, along with Dr. Mary Sturge, he published a book on alcoholism titled Alcohol and the Human Body.
According to his biographers, Tan & Black (2002), "Horsley's kindness, humility, and generous spirit endeared him to patients, colleagues, and students. Born to pri |
https://en.wikipedia.org/wiki/Activity%20diagram | Activity diagrams are graphical representations of workflows of stepwise activities and actions with support for choice, iteration and concurrency. In the Unified Modeling Language, activity diagrams are intended to model both computational and organizational processes (i.e., workflows), as well as the data flows intersecting with the related activities. Although activity diagrams primarily show the overall flow of control, they can also include elements showing the flow of data between activities through one or more data stores.
Construction
Activity diagrams are constructed from a limited number of shapes, connected with arrows. The most important shape types:
stadia represent actions;
diamonds represent decisions;
bars represent the start (split) or end (join) of concurrent activities;
a black circle represents the start (initial node) of the workflow;
an encircled black circle represents the end (final node).
Arrows run from the start towards the end and represent the order in which activities happen.
Activity diagrams can be regarded as a form of a structured flowchart combined with a traditional data flow diagram. Typical flowchart techniques lack constructs for expressing concurrency. However, the join and split symbols in activity diagrams only resolve this for simple cases; the meaning of the model is not clear when they are arbitrarily combined with decisions or loops.
While in UML 1.x, activity diagrams were a specialized form of state diagrams, in UML 2.x, the activity diagrams were reformalized to be based on Petri net-like semantics, increasing the scope of situations that can be modeled using activity diagrams. These changes cause many UML 1.x activity diagrams to be interpreted differently in UML 2.x.
UML activity diagrams in version 2.x can be used in various domains, e.g. in design of embedded systems. It is possible to verify such a specification using model checking technique.
See also
Specification and Description Language
Busines |
https://en.wikipedia.org/wiki/Why%27s%20%28poignant%29%20Guide%20to%20Ruby | why's (poignant) Guide to Ruby, sometimes called w(p)GtR or just "the poignant guide", is an introductory book to the Ruby programming language, written by why the lucky stiff. The book is distributed under the Creative Commons Attribution-ShareAlike license.
The book is unusual among programming books in that it includes much strange humor and many narrative side tracks which are sometimes completely unrelated to the topic. Many motifs have become inside jokes in the Ruby community, such as references to the words "chunky bacon". The book includes many characters which have become popular as well, particularly the cartoon foxes and Trady Blix, a large black feline friend of why's, who acts as a guide to the foxes (and occasionally teaches them some Ruby).
The book is published in HTML and PDF. Chapter three was reprinted in The Best Software Writing I: Selected and Introduced by Joel Spolsky (Apress, 2005).
Contents
About this book
Kon'nichi wa, Ruby
A Quick (and Hopefully Painless) Ride Through Ruby (with Cartoon Foxes): basic introduction to central Ruby concepts
Floating Little Leaves of Code: evaluation and values, hashes and lists
Them What Make the Rules and Them What Live the Dream: case/when, while/until, variable scope, blocks, methods, class definitions, class attributes, objects, modules, introspection in IRB, dup, self, module
Downtown: metaprogramming, regular expressions
When You Wish Upon a Beard: send method, new methods in existing classes
The following chapters are "Expansion Packs":
The Tiger's Vest (with a Basic Introduction to IRB): discusses IRB, the interactive Ruby interpreter.
External links
Original Site
Actively maintained fork
3rd-party PDF version: Ruby Inside
Computer programming books
Creative Commons-licensed books
Ruby (programming language)
Books about free software |
https://en.wikipedia.org/wiki/Enzyme%20promiscuity | Enzyme promiscuity is the ability of an enzyme to catalyse a fortuitous side reaction in addition to its main reaction. Although enzymes are remarkably specific catalysts, they can often perform side reactions in addition to their main, native catalytic activity. These promiscuous activities are usually slow relative to the main activity and are under neutral selection. Despite ordinarily being physiologically irrelevant, under new selective pressures these activities may confer a fitness benefit therefore prompting the evolution of the formerly promiscuous activity to become the new main activity. An example of this is the atrazine chlorohydrolase (atzA encoded) from Pseudomonas sp. ADP that evolved from melamine deaminase (triA encoded), which has very small promiscuous activity toward atrazine, a man-made chemical.
Introduction
Enzymes are evolved to catalyse a particular reaction on a particular substrate with a high catalytic efficiency (kcat/KM, cf. Michaelis–Menten kinetics). However, in addition to this main activity, they possess other activities that are generally several orders of magnitude lower, and that are not a result of evolutionary selection and therefore do not partake in the physiology of the organism.
This phenomenon allows new functions to be gained as the promiscuous activity could confer a fitness benefit under a new selective pressure leading to its duplication and selection as a new main activity.
Enzyme evolution
Duplication and divergence
Several theoretical models exist to predict the order of duplication and specialisation events, but the actual process is more intertwined and fuzzy (§ Reconstructed enzymes below). On one hand, gene amplification results in an increase in enzyme concentration, and potentially freedom from a restrictive regulation, therefore increasing the reaction rate (v) of the promiscuous activity of the enzyme making its effects more pronounced physiologically ("gene dosage effect"). On the other, enzymes may evo |
https://en.wikipedia.org/wiki/OneMine | OneMine is non-profit entity and searchable online global mining and minerals library.
History
OneMine is a non-profit entity governed by a steering committee whose members are nominated and serve for a term of three calendar years. It was launched as a collaborative effort between professional societies in the mining and minerals related fields to promote access to technical articles, periodicals, books, and other published work as research source for engineers in related disciplines. OneMine is a searchable online global mining and minerals library. OneMine currently contains more than 117,000 articles, technical papers, and other documents from mining societies around the world. Professional societies and associations in the mining, metallurgical, and tunneling communities may have their technical papers, journals, periodicals, and other published works considered for inclusion in the OneMine library.
Contents
OneMine contains over 130 years of peer reviewed works from professional societies including:
AIME – The American Institute of Mining, Metallurgical, and Petroleum Engineers
AusIMM – The Australasian Institute of Mining and Metallurgy
CIM - The Canadian Institute of Mining, Metallurgy and Petroleum
DFI – Deep Foundations Institute
IMMS – International Marine Minerals Society
IIMP - Instituto de Ingenieros de Minas del Peru
NIOSH – National Institute for Occupational Safety and Health
SAIMM – The Southern African Institute of Mining and Metallurgy
SME – Society for Mining, Metallurgy, and Exploration
TMS – The Minerals, Metals & Materials Society
Among the published works accessible in OneMine are:
Mining Engineering Magazine peer reviewed technical papers
SME Transactions – an annual publication of peer reviewed technical papers by the SME
Tunneling and Underground Construction – a monthly periodical
SME Annual Meeting Proceedings
Technical papers by the AIME, AusIMM, CIM, DFI, IMMS, IIMP, NIOSH, SAIMM, SME and TMS.
Proceedings from sev |
https://en.wikipedia.org/wiki/WWWJDIC | WWWJDIC is an online Japanese dictionary based on the electronic dictionaries compiled and collected by Australian academic Jim Breen. The main Japanese–English dictionary file (EDICT) contains over 180,000 entries, and the ENAMDICT dictionary contains over 720,000 Japanese surnames, first names, place names and product names. WWWJDIC also contains several specialized dictionaries covering topics such as life sciences, law, computing, engineering, etc.
For example sentences with Japanese words, WWWJDIC makes use of a sentence database from the Tatoeba project, largely based on the Tanaka Corpus. Unlike the original Tanaka Corpus, the sentences from the Tatoeba project are not public domain, but are available under the non-restrictive CC-BY license. The sentence collection contains over 150,000 sentence pairs in Japanese and English.
In addition to Japanese–English, the dictionary has Japanese paired with German, French, Russian, Hungarian, Swedish, Spanish and Dutch. However, currently there are no example sentences for these languages.
The dictionary is updated freely and may be copied under its own licence arrangements.
Several mirror sites of the main WWWJDIC also exist around the world. These sites update daily from the home site at the Electronic Dictionary Research and Development Group (EDRDG).
See also
Japanese language education |
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