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https://en.wikipedia.org/wiki/Animal%20domestication%20and%20management%20in%20the%20Philippines | Domesticated animals in the Philippines include pigs, chickens, water buffalo, goats, cats, and dogs. Domestication is when a species is selectively bred to produce certain traits that are seen as desirable. Some desirable traits include quicker growth and maturity, increased fertility, adaptability to various conditions, and living in herds. Domesticated animals play an important socioeconomic role in the Philippines, as seen through their widespread use in rituals.
Pigs
There is evidence for pigs in the Philippines during the Neolithic and Iron Age. Pig remains were found at the Nagsabaran site in Alaguia, Lal-lo town in Cagayan Province, Northern Luzon. Of the pig remains, two different taxa were found: Sus philippensis (also known as the Philippine warty pig) and an unknown species. The unknown species’ remains are similar to Sus Scrofa, which is a domesticated pig found in Luzon. Through morphometric examination of teeth, researchers concluded that the unknown species of pig was likely domesticated due to its larger size than the Philippine warty pig and its similarity to the domesticated species Sus scrofa. A carbon-14 date on a premolar of the unknown species dates domesticated pigs at ca. 2500-2200 cal BC. Faunal remains of predominantly wild pig were found at the Nagsabaran site, indicating that hunting was the primary subsistence strategy during the Neolithic and Iron Age and pigs were not domesticated for the sole purpose of subsistence.
In present-day villages located in Luzon and Palawan, domesticated pigs (Sus scrofa) are only eaten for ceremonial purposes, while wild pigs (Sus philippensis) are never used for rituals. In Borneo, indigenous groups use pigs for trade and social status. Throughout the Philippines, domesticated pigs are bred for socioeconomic reasons and are used for ceremonies, bride wealth, burials, and ritual feasting. Domesticated pigs show status and wealth and are used to make and strengthen alliances. They are also used as deity |
https://en.wikipedia.org/wiki/GEUP | GEUP is a commercial interactive geometry software program, similar to Cabri Geometry. Originally using the Spanish language, it was programmed by Ramón
Alvarez Galván. Recent versions include support for three-dimensional geometry. |
https://en.wikipedia.org/wiki/Hebrew%20abbreviations | Abbreviations () are a common part of the Hebrew language, with many organizations, places, people and concepts known by their abbreviations.
Typography
Acronyms in Hebrew use a special punctuation mark called gershayim (). This mark is placed between the last two letters of the non-inflected form of the acronym (e.g. "report" in singular is , hence the plural ). Acronyms can be formed from strings of single initial letters, e.g. (for ), or multiple initial letters, e.g. (for , the Holy Land) or (for , Rishon LeZion).
If the acronym is read as is, then the spelling should be with a final form letter. If, on the other hand, the acronym is read as the complete phrase or read as the individual letters, then it should be spelled with a medial form letter. In practice, this rule is often ignored, and the acronyms spelled either way.
Abbreviations that are truncations of a single word, consisting of the first letter or first several letters of that word (as opposed to acronyms formed from initials or truncations of more than one word) are denoted using the punctuation mark geresh () by placing the sign after the last letter of the abbreviation (e.g. "Ms.": ). However, in practice, single and double quotes are often used instead of the special punctuation marks (for which most keyboards do not have keys), with the single quote used both in acronyms and abbreviations.
In Modern Hebrew, as in many European languages, periods sometimes used to mark an abbreviation (e.g., for , "ID card", or for , "P.O.B.") this notation is mainly used in technical writing and regarded nonstandard by the Hebrew Academy.
Pronunciation
Often (and especially when they describe a noun), Hebrew acronyms are pronounced by the insertion of a vowel sound (usually ) between the letters. These vowels often appear in transliterations to other scripts. Examples include Shas (), Tanakh () and Shabak (). There are exceptions to the use of "a", such as Etzel ().
When one of the letters is vav or |
https://en.wikipedia.org/wiki/McStas | McStas is free and open-source (GNU Public License) software simulator for neutron scattering experiments. McStas is an abbreviation for Monte carlo Simulation of triple axis spectrometers, but the software can be used to simulate all types of neutron scattering instruments. The software is based on both Monte Carlo methods and ray tracing. A special compiler translates a domain-specific language describing the neutron instrument geometry and component definitions (written in C) to a stand-alone C code.
The basics of McStas was written in 1997 at Risø for simulation of their neutron experiments, that were based at the DR3 reactor that was shut down in year 2000. After the fusion of Risø with the Technical University of Denmark, McStas is currently developed at the Physics department of DTU and Institut Laue-Langevin, with involvement from the Niels Bohr Institute and Paul Scherrer Institute. The Copenhagen-based Data Management and Software Centre of the European Spallation Source is also expected to become a partner since many of the future instruments are being simulated using McStas.
McXtrace, an equivalent simulation package using X-rays instead of neutrons, started being developed in 2009 and it is now freely available.
Official partner sites are
The Physics department at DTU
The European Spallation Source
The Institut Laue-Langevin
The Niels Bohr Institute
The Paul Scherrer Institute
See also
Neutron-acceptance diagram shading (NADS)
VITESS, another neutron raytracing software package |
https://en.wikipedia.org/wiki/Animal%20science | Animal science is described as "studying the biology of animals that are under the control of humankind". It can also be described as the production and management of farm animals. Historically, the degree was called animal husbandry and the animals studied were livestock species, like cattle, sheep, pigs, poultry, and horses. Today, courses available look at a broader area, including companion animals, like dogs and cats, and many exotic species. Degrees in Animal Science are offered at a number of colleges and universities. Animal science degrees are often offered at land-grant universities, which will often have on-campus farms to give students hands-on experience with livestock animals.
Education
Professional education in animal science prepares students for careers in areas such as animal breeding, food and fiber production, nutrition, animal agribusiness, animal behavior, and welfare. Courses in a typical Animal Science program may include genetics, microbiology, animal behavior, nutrition, physiology, and reproduction. Courses in support areas, such as genetics, soils, agricultural economics and marketing, legal aspects, and the environment also are offered.
Bachelor degree
At many universities, a Bachelor of Science (BS) degree in Animal Science allows emphasis in certain areas. Typical areas are species-specific or career-specific. Species-specific areas of emphasis prepare students for a career in dairy management, beef management, swine management, sheep or small ruminant management, poultry production, or the horse industry. Other career-specific areas of study include pre-veterinary medicine studies, livestock business and marketing, animal welfare and behavior, animal nutrition science, animal reproduction science, or genetics. Youth programs are also an important part of animal science programs.
Pre-veterinary emphasis
Many schools that offer a degree option in Animal Science also offer a pre-veterinary emphasis such as Iowa State University, th |
https://en.wikipedia.org/wiki/Second-generation%20wavelet%20transform | In signal processing, the second-generation wavelet transform (SGWT) is a wavelet transform where the filters (or even the represented wavelets) are not designed explicitly, but the transform consists of the application of the Lifting scheme.
Actually, the sequence of lifting steps could be converted to a regular discrete wavelet transform, but this is unnecessary because both design and application is made via the lifting scheme.
This means that they are not designed in the frequency domain, as they are usually in the classical (so to speak first generation) transforms such as the DWT and CWT).
The idea of moving away from the Fourier domain was introduced independently by David Donoho and Harten in the early 1990s.
Calculating transform
The input signal is split into odd and even samples using shifting and downsampling. The detail coefficients are then interpolated using the values of and the prediction operator on the even values:
The next stage (known as the updating operator) alters the approximation coefficients using the detailed ones:
The functions prediction operator and updating operator
effectively define the wavelet used for decomposition.
For certain wavelets the lifting steps (interpolating and updating) are repeated several times before the result is produced.
The idea can be expanded (as used in the DWT) to create a filter bank with a number of levels.
The variable tree used in wavelet packet decomposition can also be used.
Advantages
The SGWT has a number of advantages over the classical wavelet transform in that it is quicker to compute (by a factor of 2) and it can be used to generate a multiresolution analysis that does not fit a uniform grid. Using a priori information the grid can be designed to allow the best analysis of the signal to be made.
The transform can be modified locally while preserving invertibility; it can even adapt to some extent to the transformed signal. |
https://en.wikipedia.org/wiki/Summation%20equation | In mathematics, a summation equation or discrete integral equation is an equation in which an unknown function appears under a summation sign. The theories of summation equations and integral equations can be unified as integral equations on time scales using time scale calculus. A summation equation compares to a difference equation as an integral equation compares to a differential equation.
The Volterra summation equation is:
where x is the unknown function, and s, a, t are integers, and f, k are known functions. |
https://en.wikipedia.org/wiki/Prenatal%20testosterone%20transfer | Prenatal Testosterone Transfer (also known as prenatal androgen transfer or prenatal hormone transfer) refers to the phenomenon in which testosterone synthesized by a developing male fetus transfers to one or more developing fetuses within the womb and influences development. This typically results in the partial masculinization of specific aspects of female behavior, cognition, and morphology, though some studies have found that testosterone transfer can cause an exaggerated masculinization in males. There is strong evidence supporting the occurrence of prenatal testosterone transfer in rodents and other litter-bearing species, such as pigs. When it comes to humans, studies comparing dizygotic opposite-sex and same-sex twins suggest the phenomenon may occur, though the results of these studies are often inconsistent.
Mechanisms of transfer
Testosterone is a steroid hormone; therefore it has the ability to diffuse through the amniotic fluid between fetuses. In addition, hormones can transfer among fetuses through the mother's bloodstream.
Consequences of testosterone transfer
During prenatal development, testosterone exposure is directly responsible for masculinizing the genitals and brain structures. This exposure leads to an increase in male-typical behavior.
Animal studies
Most animal studies are performed on rats or mice. In these studies, the amount of testosterone each individual fetus is exposed to depends on its intrauterine position (IUP). Each gestating fetus not at either end of the uterine horn is surrounded by either two males (2M), two females (0M), or one female and one male (1M). Development of the fetus varies widely according to its IUP.
Mice
In mice, prenatal testosterone transfer causes higher blood concentrations of testosterone in 2M females when compared to 1M or 0M females. This has a variety of consequences on later female behavior, physiology, and morphology.
Below is a table comparing physiological, morphological, and behavioral diffe |
https://en.wikipedia.org/wiki/VIP2%20experiment | The VIP2 experiment (Violation of the Pauli Principle) is an atomic physics experiment studying the possible violation of the Pauli exclusion principle for electrons. The experiment is located in the underground laboratory of Gran Sasso, LNGS-INFN, near the town L'Aquila in Italy. It is run by an international collaboration of researchers from Austria, Italy, France and Romania. The sources for funding include the INFN (Italy), the Austrian Science Fund and the John Templeton Foundation (JTF). Within the JTF project, also the implications for physics, cosmology and philosophy are being investigated.
Principle of the experiment
The different approaches to investigate the Pauli exclusion principle need to be distinguished concerning their possible fulfillment of the Messiah–Greenberg superselection rule. This rule states that the symmetry of the wave function of a steady state is constant in time. As a consequence, the symmetry of a quantum state can only change if a particle, which is new to the system, interacts with the state.
One way to fulfill this rule and test the Pauli exclusion principle with high precision is to introduce "new" electrons in a conductor. The electrons form new quantum states with the atoms in the conductor. These "new" states could violate the Pauli exclusion principle. The aim of VIP2 is to search for new quantum states, which have a symmetric component in an otherwise antisymmetric state. These non-Paulian states can be identified by the characteristic X-rays emitted during Pauli exclusion principle—prohibited atomic transitions to the ground state. An example for a transition of this kind would be a third electron arriving on the 1s level. The emitted X-rays are detected by silicon drift detectors.
The energies of the transitions between Pauli-forbidden states were calculated using a multi-configuration Dirac–Fock method and they differ slightly from the corresponding normal transition. For example the Pauli-forbidden K-alpha transitio |
https://en.wikipedia.org/wiki/Pairing%20function | In mathematics, a pairing function is a process to uniquely encode two natural numbers into a single natural number.
Any pairing function can be used in set theory to prove that integers and rational numbers have the same cardinality as natural numbers.
Definition
A pairing function is a bijection
More generally, a pairing function on a set A is a function that maps each pair of elements from A into an element of A, such that any two pairs of elements of A are associated with different elements of A, or a bijection from to A.
Hopcroft and Ullman pairing function
Hopcroft and Ullman (1979) define the following pairing function: , where . This is the same as the Cantor pairing function below, shifted to exclude 0 (i.e., , , and ).
Cantor pairing function
The Cantor pairing function is a primitive recursive pairing function
defined by
where .
It can also be expressed as .
It is also strictly monotonic w.r.t. each argument, that is, for all , if , then ; similarly, if , then .
The statement that this is the only quadratic pairing function is known as the Fueter–Pólya theorem. Whether this is the only polynomial pairing function is still an open question. When we apply the pairing function to and we often denote the resulting number as .
This definition can be inductively generalized to the
for as
with the base case defined above for a pair:
Inverting the Cantor pairing function
Let be an arbitrary natural number. We will show that there exist unique values such that
and hence that the function is invertible. It is helpful to define some intermediate values in the calculation:
where is the triangle number of . If we solve the quadratic equation
for as a function of , we get
which is a strictly increasing and continuous function when is non-negative real. Since
we get that
and thus
where is the floor function.
So to calculate and from , we do:
Since the Cantor pairing function is invertible, it must be one-to-one and onto.
E |
https://en.wikipedia.org/wiki/Currency%20Symbols%20%28Unicode%20block%29 | Currency Symbols is a Unicode block containing characters for representing unique monetary signs. Many currency signs can be found in other Unicode blocks, especially when the currency symbol is unique to a country that uses a script not generally used outside that country.
The display of Unicode currency symbols among various typefaces is inconsistent, more so than other characters in the repertoire. The French franc sign (U+20A3) is typically displayed as a struck-through F, but various versions of Garamond display it as an Fr ligature. The peseta sign (U+20A7), inherited from code page 437, is usually displayed as a Pts ligature, but Roboto displays it as a Pt ligature and Arial Unicode MS displays it as a partially struck-through P. The rupee sign (U+20A8) is usually displayed as an Rs digraph, but Microsoft Sans Serif uses the quantity-neutral "Rp" digraph instead.
Block
History
The following Unicode-related documents record the purpose and process of defining specific characters in the Currency Symbols block: |
https://en.wikipedia.org/wiki/Glossary%20of%20ichthyology | This glossary of ichthyology is a list of definitions of terms and concepts used in ichthyology, the study of fishes.
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
R
S
T
U
V
W |
https://en.wikipedia.org/wiki/Truth-table%20reduction | In computability theory, a truth-table reduction is a reduction from one set of natural numbers to another.
As a "tool", it is weaker than Turing reduction, since not every Turing reduction between sets can be performed by a truth-table reduction, but every truth-table reduction can be performed by a Turing reduction. For the same reason it is said to be a stronger reducibility than Turing reducibility, because it implies Turing reducibility. A weak truth-table reduction is a related type of reduction which is so named because it weakens the constraints placed on a truth-table reduction, and provides a weaker equivalence classification; as such, a "weak truth-table reduction" can actually be more powerful than a truth-table reduction as a "tool", and perform a reduction which is not performable by truth table.
A Turing reduction from a set B to a set A computes the membership of a single element in B by asking questions about the membership of various elements in A during the computation; it may adaptively determine which questions it asks based upon answers to previous questions. In contrast, a truth-table reduction or a weak truth-table reduction must present all of its (finitely many) oracle queries at the same time. In a truth-table reduction, the reduction also gives a boolean function (a truth table) which, when given the answers to the queries, will produce the final answer of the reduction. In a weak truth-table reduction, the reduction uses the oracle answers as a basis for further computation which may depend on the given answers but may not ask further questions of the oracle.
Equivalently, a weak truth-table reduction is a Turing reduction for which the use of the reduction is bounded by a computable function. For this reason, they are sometimes referred to as bounded Turing (bT) reductions rather than as weak truth-table (wtt) reductions.
Properties
As every truth-table reduction is a Turing reduction, if A is truth-table reducible to B (A ≤tt B), |
https://en.wikipedia.org/wiki/Virtual%20IP%20address | A virtual IP address (VIP or VIPA) is an IP address that does not correspond to a physical network interface. Uses for VIPs include network address translation (especially, one-to-many NAT), fault-tolerance, and mobility.
Usage
For one-to-many NAT, a VIP address is advertised from the NAT device (often a router), and incoming data packets destined to that VIP address are routed to different actual IP addresses (with address translation). These VIP addresses have several variations and implementation scenarios, including Common Address Redundancy Protocol (CARP) and Proxy ARP. In addition, if there are multiple actual IP addresses, load balancing can be performed as part of NAT.
VIP addresses are also used for connection redundancy by providing alternative fail-over options for one machine. For this to work, the host has to run an interior gateway protocol like Open Shortest Path First (OSPF), and appear as a router to the rest of the network. It advertises virtual links connected via itself to all of its actual network interfaces. If one network interface fails, normal OSPF topology reconvergence will cause traffic to be sent via another interface.
A VIP address can be used to provide nearly unlimited mobility. For example, if an application has an IP address on a physical subnet, that application can be moved only to a host on that same subnet. VIP addresses can be advertised on their own subnet, so its application can be moved anywhere on the reachable network without changing addresses.
See also
Anycast, single IP bound simultaneously to many, potentially geographically disparate, NICs
IP network multipathing (IPMP), Solaris virtual IP implementation for fault-tolerance and load balancing
VLAN
Notes |
https://en.wikipedia.org/wiki/WakaWaka | WakaWaka is a global social enterprise that developed and sold portable solar products for people without access to electricity. The company was founded in 2012 by Maurits Groen and Camille van Gestel. WakaWaka means “shine bright” in Swahili. For every WakaWaka purchased, one solar light was donated to a family living without access to electricity. In July 2018 TSM Business School took over the brand name and the remaining stocks of WakaWaka, after the enterprise went bankrupt after failing to raise EUR 2.5 million in growth capital.
Company history
The company was founded in 2012 by Maurits Groen and Camille van Gestel. The inspiration for WakaWaka was first sparked in 2010, as Maurits and Camille traveled through South Africa, working to offset carbon emissions from that year’s World Cup championship. Throughout their travels, they were struck by the scores of people living without access to electricity.
Funded by a Kickstarter campaign that raised $48,000, the first product produced in 2012 was the WakaWaka Light, a solar flashlight. In 2013 and 2014, the company turned to Kickstarter again and added OnePlanetCrowd to crowdfund the product development of the WakaWaka Power, a solar charger and flashlight and the WakaWaka Base, a solar home kit, raising $700,000 and $385,000 respectively.
WakaWaka opened an office in Kigali, Rwanda in 2014 and launched the Virtual Grid, the world’s first telecom-based pico solar pay-as-you-go system. Since 2019, WakaWaka Rwanda has continued independently under the name of Mother Light Africa.
In the fall of 2015, Maurits Groen was named #1 in Trouw's Sustainability Index of the 100 most sustainable people in the Netherlands.
In 2016, WakaWaka has started selling through retail, in the UK, France, Germany, Switzerland and Scandinavia.
Business model
Through the company's Share the Sun model, when customers buy a WakaWaka they also give a solar light to a family living without access to electricity. In the United States |
https://en.wikipedia.org/wiki/Buffer%20analysis | In geographic information systems (GIS) and spatial analysis, buffer analysis is the determination of a zone around a geographic feature containing locations that are within a specified distance of that feature, the buffer zone (or just buffer). A buffer is likely the most commonly used tool within the proximity analysis methods.
History
The buffer operation has been a core part of GIS functionality since the original integrated GIS software packages of the late 1970s and early 1980s, such as ARC/INFO, Odyssey, and MOSS. Although it has been one of the most widely used GIS operations in subsequent years, in a wide variety of applications, there has been little published research on the tool itself, except for the occasional development of a more efficient algorithm.
Basic algorithm
The fundamental method to create a buffer around a geographic feature stored in a vector data model, with a given radius r is as follows:
Single point: Create a circle around the point with radius r.
Polyline, which consists of an ordered list of points (vertices) connected by straight lines. This is also used for the boundary of a polygon.
Create a circle buffer around each vertex
Create a rectangle along each line segment by creating a duplicate line segment offset the distance r perpendicular to each side.
Merge or dissolve the rectangles and circles into a single polygon.
Software implementations of the buffer operation typically use alterations of this strategy to process more efficiently and accurately.
Planar vs. geodesic distance
Traditional implementations assumed the buffer was being created on a planar cartesian coordinate space (i.e., created by a map projection) using Euclidean geometry, because the mathematics and computation involved is relatively simple, which was important given the computing power available in the late 1970s. Due to the inherent distortions caused by map projections, the buffer computed this way will not be identical to one drawn on the surfac |
https://en.wikipedia.org/wiki/Chandrasekhar%27s%20H-function | In atmospheric radiation, Chandrasekhar's H-function appears as the solutions of problems involving scattering, introduced by the Indian American astrophysicist Subrahmanyan Chandrasekhar. The Chandrasekhar's H-function defined in the interval , satisfies the following nonlinear integral equation
where the characteristic function is an even polynomial in satisfying the following condition
.
If the equality is satisfied in the above condition, it is called conservative case, otherwise non-conservative. Albedo is given by . An alternate form which would be more useful in calculating the H function numerically by iteration was derived by Chandrasekhar as,
.
In conservative case, the above equation reduces to
.
Approximation
The H function can be approximated up to an order as
where are the zeros of Legendre polynomials and are the positive, non vanishing roots of the associated characteristic equation
where are the quadrature weights given by
Explicit solution in the complex plane
In complex variable the H equation is
then for , a unique solution is given by
where the imaginary part of the function can vanish if is real i.e., . Then we have
The above solution is unique and bounded in the interval for conservative cases. In non-conservative cases, if the equation admits the roots , then there is a further solution given by
Properties
. For conservative case, this reduces to .
. For conservative case, this reduces to .
If the characteristic function is , where are two constants(have to satisfy ) and if is the nth moment of the H function, then we have
and
See also
Chandrasekhar's X- and Y-function
External links
MATLAB function to calculate the H function https://www.mathworks.com/matlabcentral/fileexchange/29333-chandrasekhar-s-h-function |
https://en.wikipedia.org/wiki/DYNAMO%20%28programming%20language%29 | DYNAMO (DYNAmic MOdels) is a simulation language and accompanying graphical notation developed within the system dynamics analytical framework. It was originally for industrial dynamics but was soon extended to other applications, including population and resource studies
and urban planning.
DYNAMO was initially developed under the direction of Jay Wright Forrester in the late 1950s, by Dr. Phyllis Fox,
Alexander L. Pugh III, Grace Duren,
and others
at the M.I.T. Computation Center.
DYNAMO was used for the system dynamics simulations of global resource depletion reported in the Club of Rome's Limits to Growth, but has since fallen into disuse.
Beginnings
In 1958, Forrester unwittingly instigated DYNAMO's development when he asked an MIT staff programmer to compute needed solutions to some equations, for a Harvard Business Review paper he was writing about industrial dynamics.
The programmer, Richard Bennett, chose to implement a system (SIMPLE - "Simulation of Industrial Management Problems with Lots of Equations") that took coded equations as symbolic input and computed solutions. SIMPLE became the proof-of-concept for DYNAMO: rather than have a specialist programmer "hard-code" a special-purpose solver in a general purpose programming language, users could specify a system's equations in a special simulation language and get simulation output from one program execution.
Design goals
DYNAMO was designed to emphasize the following:
ease-of-use for the industrial dynamics modeling community (who were not assumed to be expert programmers);
immediate execution of the compiled model, without producing an intermediate object file; and
providing graphical output, with line printer and pen plotter graphics.
Among the ways in which DYNAMO was above the standard of the time, it featured units checking of numerical types and relatively clear error messages.
Implementation
The earliest versions were written in assembly language for the IBM 704, then for the IBM 7 |
https://en.wikipedia.org/wiki/UDP%20hole%20punching | UDP hole punching is a commonly used technique employed in network address translation (NAT) applications for maintaining User Datagram Protocol (UDP) packet streams that traverse the NAT. NAT traversal techniques are typically required for client-to-client networking applications on the Internet involving hosts connected in private networks, especially in peer-to-peer, Direct Client-to-Client (DCC) and Voice over Internet Protocol (VoIP) deployments.
UDP hole punching establishes connectivity between two hosts communicating across one or more network address translators. Typically, third-party hosts on the public transit network are used to establish UDP port states that may be used for direct communications between the communicating hosts. Once port state has been successfully established and the hosts are communicating, port state may be maintained either by normal communications traffic, or in the prolonged absence thereof, by keep-alive packets, usually consisting of empty UDP packets or packets with minimal, non-intrusive content.
Overview
UDP hole punching is a method for establishing bidirectional UDP connections between Internet hosts in private networks using network address translators. The technique is not applicable in all scenarios or with all types of NATs, as NAT operating characteristics are not standardized.
Hosts with network connectivity inside a private network connected via a NAT to the Internet typically use the Session Traversal Utilities for NAT (STUN) method or Interactive Connectivity Establishment (ICE) to determine the public address of the NAT that its communications peers require. In this process another host on the public network is used to establish port mapping and other UDP port state that is assumed to be valid for direct communication between the application hosts. Since UDP state usually expires after short periods of time in the range of tens of seconds to a few minutes, and the UDP port is closed in the process, UDP hole pu |
https://en.wikipedia.org/wiki/Genetically%20modified%20food%20controversies | Genetically modified food controversies are disputes over the use of foods and other goods derived from genetically modified crops instead of conventional crops, and other uses of genetic engineering in food production. The disputes involve consumers, farmers, biotechnology companies, governmental regulators, non-governmental organizations, and scientists. The key areas of controversy related to genetically modified food (GM food or GMO food) are whether such food should be labeled, the role of government regulators, the objectivity of scientific research and publication, the effect of genetically modified crops on health and the environment, the effect on pesticide resistance, the impact of such crops for farmers, and the role of the crops in feeding the world population. In addition, products derived from GMO organisms play a role in the production of ethanol fuels and pharmaceuticals.
Specific concerns include mixing of genetically modified and non-genetically modified products in the food supply, effects of GMOs on the environment, the rigor of the regulatory process, and consolidation of control of the food supply in companies that make and sell GMOs. Advocacy groups such as the Center for Food Safety, Organic Consumers Association, Union of Concerned Scientists, and Greenpeace say risks have not been adequately identified and managed, and they have questioned the objectivity of regulatory authorities.
The safety assessment of genetically engineered food products by regulatory bodies starts with an evaluation of whether or not the food is substantially equivalent to non-genetically engineered counterparts that are already deemed fit for human consumption. No reports of ill effects have been documented in the human population from genetically modified food.
There is a scientific consensus that currently available food derived from GM crops poses no greater risk to human health than conventional food, but that each GM food needs to be tested on a case-by-case |
https://en.wikipedia.org/wiki/Andreas%20Seeger | Andreas Seeger is a mathematician who works in the field of harmonic analysis. He is a professor of mathematics at the University of Wisconsin–Madison. He received his PhD from Technische Universität Darmstadt in 1985 under the supervision of Walter Trebels.
He was elected a fellow of the American Mathematical Society in 2014 for his contributions to Fourier integral operators, local smoothing,
oscillatory integrals, and Fourier multipliers. In 2017, he was awarded the Humboldt Prize.
He was awarded a Simons Fellowship in 2019. |
https://en.wikipedia.org/wiki/Myco-heterotrophy | Myco-heterotrophy (from Greek μύκης , "fungus", ἕτερος , "another", "different" and τροφή , "nutrition") is a symbiotic relationship between certain kinds of plants and fungi, in which the plant gets all or part of its food from parasitism upon fungi rather than from photosynthesis. A myco-heterotroph is the parasitic plant partner in this relationship. Myco-heterotrophy is considered a kind of cheating relationship and myco-heterotrophs are sometimes informally referred to as "mycorrhizal cheaters". This relationship is sometimes referred to as mycotrophy, though this term is also used for plants that engage in mutualistic mycorrhizal relationships.
Relationship between myco-heterotrophs and host fungi
Full (or obligate) myco-heterotrophy exists when a non-photosynthetic plant (a plant largely lacking in chlorophyll or otherwise lacking a functional photosystem) gets all of its food from the fungi that it parasitizes. Partial (or facultative) myco-heterotrophy exists when a plant is capable of photosynthesis, but parasitizes fungi as a supplementary food supply. There are also plants, such as some orchid species, that are non-photosynthetic and obligately myco-heterotrophic for part of their life cycle, and photosynthetic and facultatively myco-heterotrophic or non-myco-heterotrophic for the rest of their life cycle. Not all non-photosynthetic or "achlorophyllous" plants are myco-heterotrophic – some non-photosynthetic plants like dodder directly parasitize the vascular tissue of other plants. The partial or full loss of photosynthesis is reflected by extreme physical and functional reductions of plastid genomes in mycoheterophic plants, an ongoing evolutionary process.
In the past, non-photosynthetic plants were mistakenly thought to get food by breaking down organic matter in a manner similar to saprotrophic fungi. Such plants were therefore called "saprophytes". It is now known that these plants are not physiologically capable of directly breaking down organ |
https://en.wikipedia.org/wiki/Facebook%20Beacon | Beacon formed part of Facebook's advertisement system that sent data from external websites to Facebook, for the purpose of allowing targeted advertisements and allowing users to share their activities with their friends. Beacon reported to Facebook on Facebook's members' activities on third-party sites that also participated with Beacon. These activities were published in users' News Feed. This occurred even when users were not connected to Facebook, and happened without the knowledge of the Facebook user. The service was controversial and became the target of a class-action lawsuit, resulting in it shutting down in September 2009. One of the main concerns was that Beacon did not give the user the option to block the information from being sent to Facebook. Beacon was launched on November 6, 2007, with 44 partner websites. Mark Zuckerberg, CEO of Facebook, characterized Beacon on the Facebook Blog in November 2011 as a "mistake." Although Beacon was unsuccessful, it did pave the way for Facebook Connect, which has become widely popular.
Privacy concerns and litigation
Beacon created considerable controversy soon after it was launched, due to privacy concerns. On November 20, 2007, civic action group MoveOn.org created a Facebook group and online petition demanding that Facebook not publish their activity from other websites without explicit permission from the user. In fewer than ten days, this group gained 50,000 members. After the class-action lawsuit, Lane v. Facebook, Inc., Beacon was changed to require that any actions transmitted to the website would have to be approved by the Facebook user before being published. On November 29, 2007, Stefan Berteau, a security researcher for Computer Associates, published a note on his tests of the Beacon system. He found that data was still being collected and sent to Facebook despite users' opt-outs and not being logged in to Facebook at the time. This revelation was in direct contradiction to the statements made by Cha |
https://en.wikipedia.org/wiki/A%20History%20of%20the%20Mind | A History of the Mind: Evolution and the Birth of Consciousness is a 1992 book about the mind–body problem by the psychologist Nicholas Humphrey. Humphrey advances a hypothesis about consciousness that has been criticised as speculative.
Summary
Humphrey describes his book as "a partial history of a part of what constitutes the human mind: an evolutionary history of how sensory consciousness has come into the world and what it is doing there." He discusses the views of the poet Samuel Taylor Coleridge and the philosophers Colin McGinn and Daniel Dennett, and the phenomenon known as blindsight, in which people who are blind in a large part of the visual field nevertheless retain "certain perceptual faculties" and apparently have "perception without sensation".
Publication history
A History of the Mind was first published by Chatto & Windus in 1992. In 1993, it was published by Vintage Books.
Reception
A History of the Mind received positive reviews from the science journalist Marek Kohn in New Statesman and Society, Francisca Goldsmith in Library Journal, and from Publishers Weekly, mixed reviews from the biologist Lewis Wolpert in New Scientist and the psychologist George Armitage Miller in The New York Times Book Review, and negative reviews from John C. Marshall in The Times Literary Supplement and McGinn in the London Review of Books.
Kohn described the book as "absorbing and stimulating". It referred to Humphrey's style of writing as "personal and informal". Goldsmith wrote that the book would appeal to both "interested lay readers" and scholars. Publishers Weekly described the book as "highly stimulating" and "unorthodox". It credited Humphrey with "Lightening his often technical discussion with thought experiments, drawings and illustrative examples". Wolpert considered the book's title misleading, arguing that its primary subject was consciousness. Though he found the book clever and well-written, he believed that, like similar books by other authors, it |
https://en.wikipedia.org/wiki/Deleveraging | At the micro-economic level, deleveraging refers to the reduction of the leverage ratio, or the percentage of debt in the balance sheet of a single economic entity, such as a household or a firm. It is the opposite of leveraging, which is the practice of borrowing money to acquire assets and multiply gains and losses.
At the macro-economic level, deleveraging of an economy refers to the simultaneous reduction of debt levels in multiple sectors, including private sectors and the government sector. It is usually measured as a decline of the total debt to GDP ratio in the national accounts. The deleveraging of an economy following a financial crisis has significant macro-economic consequences and is often associated with severe recessions.
In microeconomics
While leverage allows a borrower to acquire assets and multiply gains in good times, it also leads to multiple losses in bad times. During a market downturn when the value of assets and income plummets, a highly leveraged borrower faces heavy losses due to his or her obligation to the service of high levels of debt. If the value of assets falls below the value of debt, the borrower then has a high risk to default. Deleveraging reduces the total amplification of market volatility on the borrower's balance sheet. It means giving up potential gains in good times, in exchange for lower risk of heavy loss and nasty default in bad times.
However, precaution is not the most common reason for deleveraging. Deleveraging usually happens after a market downturn and hence is driven by the need to cover loss, which can deplete capital, build a less risky profile, or is required by nervous lenders to prevent default. In the last case, lenders lower the leverage offered by asking for a higher level of collateral and down payment. It is estimated that from 2006 to 2008, the average down payment required for a home buyer in the US increased from 5% to 25%, a decrease of leverage from 20 to 4.
To deleverage, one needs to raise c |
https://en.wikipedia.org/wiki/160th%20meridian%20east | The meridian 160° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole.
The 160th meridian east forms a great circle with the 20th meridian west.
In Antarctica, the meridian defines the border between the Australian Antarctic Territory and the Ross Dependency.
From Pole to Pole
Starting at the North Pole and heading south to the South Pole, the 160th meridian east passes through:
{| class="wikitable plainrowheaders"
! scope="col" width="130" | Co-ordinates
! scope="col" | Country, territory or sea
! scope="col" | Notes
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Arctic Ocean
| style="background:#b0e0e6;" |
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | East Siberian Sea
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
| Sakha Republic
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | East Siberian Sea
| style="background:#b0e0e6;" |
|-valign="top"
|
! scope="row" |
| Sakha Republic Chukotka Autonomous Okrug — from Magadan Oblast — from
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Sea of Okhotsk
| style="background:#b0e0e6;" | Shelikhov Gulf
|-
|
! scope="row" |
| Magadan Oblast
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Sea of Okhotsk
| style="background:#b0e0e6;" | Shelikhov Gulf
|-
|
! scope="row" |
| Kamchatka Krai — Kamchatka Peninsula
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Pacific Ocean
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
| Kamchatka Krai — Kamchatka Peninsula
|-valign="top"
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Pacific Ocean
| style="background:#b0e0e6;" | Passing just east of Mokil atoll, (at ) Passing just east of Santa Isabel Island, (at )
|-
|
! sco |
https://en.wikipedia.org/wiki/Ordered%20Bell%20number | In number theory and enumerative combinatorics, the ordered Bell numbers or Fubini numbers count the number of weak orderings on a set of elements. Weak orderings arrange their elements into a sequence allowing ties, such as might arise as the outcome of a horse race). Starting from , these numbers are
The ordered Bell numbers may be computed via a summation formula involving binomial coefficients, or by using a recurrence relation. Along with the weak orderings, they count several other types of combinatorial objects that have a bijective correspondence to the weak orderings, such as the ordered multiplicative partitions of a squarefree number or the faces of all dimensions of a permutohedron.
History
The ordered Bell numbers appear in the work of , who used them to count certain plane trees with totally ordered leaves. In the trees considered by Cayley, each root-to-leaf path has the same length, and the number of nodes at distance from the root must be strictly smaller than the number of nodes at distance , until reaching the leaves. In such a tree, there are pairs of adjacent leaves, that may be weakly ordered by the height of their lowest common ancestor; this weak ordering determines the tree. call the trees of this type "Cayley trees", and they call the sequences that may be used to label their gaps (sequences of positive integers that include at least one copy of each positive integer between one and the maximum value in the sequence) "Cayley permutations".
traces the problem of counting weak orderings, which has the same sequence as its solution, to the work of . These numbers were called Fubini numbers by Louis Comtet, because they count the number of different ways to rearrange the ordering of sums or integrals in Fubini's theorem, which in turn is named after Guido Fubini. The Bell numbers, named after Eric Temple Bell, count the number of partitions of a set, and the weak orderings that are counted by the ordered Bell numbers may be interpret |
https://en.wikipedia.org/wiki/Disk%20diffusion%20test | The disk diffusion test (also known as the agar diffusion test, Kirby–Bauer test, disc-diffusion antibiotic susceptibility test, disc-diffusion antibiotic sensitivity test and KB test) is a culture-based microbiology assay used in diagnostic and drug discovery laboratories. In diagnostic labs, the assay is used to determine the susceptibility of bacteria isolated from a patient's infection to clinically approved antibiotics. This allows physicians to prescribe the most appropriate antibiotic treatment. In drug discovery labs, especially bioprospecting labs, the assay is used to screen biological material (e.g. plant extracts, bacterial fermentation broths) and drug candidates for antibacterial activity. When bioprospecting, the assay can be performed with paired strains of bacteria to achieve dereplication and provisionally identify antibacterial mechanism of action.
In diagnostic laboratories, the test is performed by inoculating the surface of an agar plate with bacteria isolated from a patient's infection. Antibiotic-containing paper disks are then applied to the agar and the plate is incubated. If an antibiotic stops the bacteria from growing or kills the bacteria, there will be an area around the disk where the bacteria have not grown enough to be visible. This is called a zone of inhibition. The susceptibility of the bacterial isolate to each antibiotic can then be semi-quantified by comparing the size of these zones of inhibition to databases of information on known antibiotic-susceptible, moderately susceptible and resistant bacteria. In this way, it is possible to identify the most appropriate antibiotic for treating a patient's infection. Although the disk diffusion test cannot be used to differentiate bacteriostatic and bactericidal activity, it is less cumbersome than other susceptibility test methods such as broth dilution.
In drug discovery labs, the disk diffusion test is performed slightly differently than in diagnostic labs. In this set |
https://en.wikipedia.org/wiki/Constraint%20graph%20%28layout%29 | In some tasks of integrated circuit layout design a necessity arises to optimize placement of non-overlapping objects in the plane. In general this problem is extremely hard, and to tackle it with computer algorithms, certain assumptions are made about admissible placements and about operations allowed in placement modifications. Constraint graphs capture the restrictions of relative movements of the objects placed in the plane. These graphs, while sharing common idea, have different definition, depending on a particular design task or its model.
Floorplanning
In floorplanning, the model of a floorplan of an integrated circuit is a set of isothetic rectangles called "blocks" within a larger rectangle called "boundary" (e.g., "chip boundary", "cell boundary").
A possible definition of constraint graphs is as follows. The constraint graph for a given floorplan is a directed graph with vertex set being the set of floorplan blocks and there is an edge from block b1 to b2 (called horizontal constraint), if b1 is completely to the left of b2 and there is an edge from block b1 to b2 (called vertical constraint), if b1 is completely below b2.
If only horizontal constraints are considered, one obtains the horizontal constraint graph. If only vertical constraints are considered, one obtains the vertical constraint graph.
Under this definition, the constraint graph can have as many as edges, where n is the number of blocks. Therefore other, less dense constraint graphs are considered. The horizontal visibility graph is a horizontal constraint graph in which the horizontal constraint between two blocks exists only if there is a horizontal line segment which connects the two blocks and does not intersect any other blocks. In other words, one block is a potential "immediate obstacle" for moving another one horizontally. The vertical visibility graph is defined in a similar way.
Channel routing
Channel routing is the problem of routing of a set of nets N which have fixe |
https://en.wikipedia.org/wiki/Message%20Handling%20System | Message Handling System (MHS) is an important early email protocol developed by Action Technologies, Inc. (ATI) in 1986. Novell licensed it in 1988 then later bought it.
Email clients
A wide variety of email clients used MHS, including:
Para-Mail - Paradox Development introduced version 2.0 along with Novell at Comdex 1986.
DaVinci Email - The first Microsoft Windows-based email client used MHS natively.
Pegasus Mail - A free mail client, this used MHS its native protocol.
ExpressIT! and ExpressIT! 2000 - Infinite Technologies' MHS compliant email clients.
FirstMail - A cut-down version of Pegasus Mail, bundled with some versions of NetWare.
Futurus TEAM - Early groupware package offering an MHS compliant email client.
MacAccess - An Apple Macintosh MHS-based email client.
Role as a gateway
MHS was a very 'open' system, and this, with Novell's encouragement, made it popular in the early 1990s as a 'glue' between not only the proprietary email systems of the day such as PROFS, SNADS, MCI, 3+Mail, cc:Mail, Para-Mail and Microsoft Mail, but also the competing standards-based SMTP and X.400. However, by 1996 it was very clear that SMTP over the Internet would take over this role.
Work-alike products
A compatible family of products from Infinite Technologies (now Captaris) and marketed under the name Connect2 were also very widely used as part of MHS-based email networks.
Decline
Novell became increasingly less supportive after their 1994 purchase of WordPerfect as they worked to transform WordPerfect Office into GroupWise.
At about the same time, confidence in the future of X.400 collapsed and SMTP email across the public internet became the compelling choice for mail between unrelated organisations, replacing MHS's former "glue" role. |
https://en.wikipedia.org/wiki/Mostafa%20El-Sayed | Mostafa A. El-Sayed (Arabic: مصطفى السيد) is an Egyptian-American physical chemist, a leading nanoscience researcher, a member of the National Academy of Sciences and a US National Medal of Science laureate. He was the editor-in-chief of the Journal of Physical Chemistry during a critical period of growth. He is also known for the spectroscopy rule named after him, the El-Sayed rule.
Early life and academic career
El-Sayed was born in Zifta, Egypt and spent his early life in Cairo. He earned his B.Sc. in chemistry from Ain Shams University Faculty of Science, Cairo in 1953. El-Sayed earned his doctoral degree in chemistry from Florida State University working with Michael Kasha, the last student of the legendary G. N. Lewis. While attending graduate school he met and married Janice Jones, his wife of 48 years. He spent time as a post-doctoral researcher at Harvard University, Yale University and the California Institute of Technology before joining the faculty of the University of California at Los Angeles in 1961. He spent over thirty years of his career at UCLA, while he and his wife raised five children (Lyla, Tarric, James, Dorea and Ivan). In 1994, he retired from UCLA and accepted the position of Julius Brown Chair and Regents Professor of Chemistry and Biochemistry at the Georgia Institute of Technology. He led the Laser Dynamics Lab there until his full retirement in 2020.
El-Sayed is a former editor-in-chief of the Journal of Physical Chemistry (1980–2004).
Research
El-Sayed and his research group have contributed to many important areas of physical and materials chemistry research. El-Sayed's research interests include the use of steady-state and ultra fast laser spectroscopy to understand relaxation, transport and conversion of energy in molecules, in solids, in photosynthetic systems, semiconductor quantum dots and metal nanostructures. The El-Sayed group has also been involved in the development of new techniques such as magnetophotonic selectio |
https://en.wikipedia.org/wiki/Canna%20leaf%20roller | Canna leaf roller refers to two different Lepidoptera species that are pests of cultivated cannas. Caterpillars of the Brazilian skipper butterfly (Calpodes ethlius), also known as the larger canna leaf roller, cut the leaves and roll them over to live inside while pupating and eating the leaf. In addition, caterpillars of the lesser canna leaf roller (Geshna cannalis), a grass moth, will sew the leaves shut before they can unfurl by spinning a silk thread around the leaf. The resultant leaf damage can be distressing to a gardener. |
https://en.wikipedia.org/wiki/Great%20American%20Interchange | The Great American Biotic Interchange (commonly abbreviated as GABI), also known as the Great American Interchange and the Great American Faunal Interchange, was an important late Cenozoic paleozoogeographic biotic interchange event in which land and freshwater fauna migrated from North America via Central America to South America and vice versa, as the volcanic Isthmus of Panama rose up from the sea floor and bridged the formerly separated continents. Although earlier dispersals had occurred, probably over water, the migration accelerated dramatically about 2.7 million years (Ma) ago during the Piacenzian age. It resulted in the joining of the Neotropic (roughly South American) and Nearctic (roughly North American) biogeographic realms definitively to form the Americas. The interchange is visible from observation of both biostratigraphy and nature (neontology). Its most dramatic effect is on the zoogeography of mammals, but it also gave an opportunity for reptiles, amphibians, arthropods, weak-flying or flightless birds, and even freshwater fish to migrate. Coastal and marine biota, however, was affected in the opposite manner; the formation of the Central American Isthmus caused what has been termed the Great American Schism, with significant diversification and extinction occurring as a result of the isolation of the Caribbean from the Pacific.
The occurrence of the interchange was first discussed in 1876 by the "father of biogeography", Alfred Russel Wallace. Wallace had spent five years exploring and collecting specimens in the Amazon basin. Others who made significant contributions to understanding the event in the century that followed include Florentino Ameghino, W. D. Matthew, W. B. Scott, Bryan Patterson, George Gaylord Simpson and S. David Webb. The Pliocene timing of the formation of the connection between North and South America was discussed in 1910 by Henry Fairfield Osborn.
Analogous interchanges occurred earlier in the Cenozoic, when the formerly |
https://en.wikipedia.org/wiki/MessagePack | MessagePack is a computer data interchange format. It is a binary form for representing simple data structures like arrays and associative arrays. MessagePack aims to be as compact and simple as possible. The official implementation is available in a variety of languages such as C, C++, C#, D, Erlang, Go, Haskell, Java, JavaScript (NodeJS), Lua, OCaml, Perl, PHP, Python, Ruby, Rust, Scala, Smalltalk, and Swift.
Data types and syntax
Data structures processed by MessagePack loosely correspond to those used in JSON format. They consist of the following element types:
nil
bool, boolean (true and false)
int, integer (up to 64 bits signed or unsigned)
float, floating point numbers (IEEE single/double precision)
str, UTF-8 string
bin, binary data (up to 232 − 1 bytes)
array
map, an associative array
ext (arbitrary data of an application-defined format, up to 232 − 1 bytes)
timestamp (ext type = −1) (up to 64-bit seconds and 32-bit nanoseconds)
Comparison to other formats
MessagePack is more compact than JSON, but imposes limitations on array and integer sizes. On the other hand, it allows binary data and non-UTF-8 encoded strings. In JSON, map keys have to be strings, but in MessagePack there is no such limitation and any type can be a map key, including types like maps and arrays, and, like YAML, numbers.
Compared to BSON, MessagePack is more space-efficient. BSON is designed for fast in-memory manipulation, whereas MessagePack is designed for efficient transmission over the wire. For example, BSON requires null terminators at the end of all strings and inserts string indexes for list elements, while MessagePack doesn't. BSON represents both arrays and maps internally as documents, which are maps, where an array is a map with keys as decimal strings counting up from 0. MessagePack on the other hand represents both maps and arrays as arrays, where each map key-value pair is contiguous, making odd items keys and even items values.
The Protocol Buffers format |
https://en.wikipedia.org/wiki/Branch%20migration | Branch migration is the process by which base pairs on homologous DNA strands are consecutively exchanged at a Holliday junction, moving the branch point up or down the DNA sequence. Branch migration is the second step of genetic recombination, following the exchange of two single strands of DNA between two homologous chromosomes. The process is random, and the branch point can be displaced in either direction on the strand, influencing the degree of which the genetic material is exchanged. Branch migration can also be seen in DNA repair and replication, when filling in gaps in the sequence. It can also be seen when a foreign piece of DNA invades the strand.
Mechanism
The mechanism for branch migration differs between prokaryotes and eukaryotes.
Prokaryotes
The mechanism for prokaryotic branch migration has been studied many times in Escherichia coli. In E. coli, the proteins RuvA and RuvB come together and form a complex that facilitates the process in a number of ways. RuvA is a tetramer and binds to the DNA at the Holliday junction when it is in the open X form. The protein binds in a way that the DNA entering/departing the junction is still free to rotate and slide through. RuvA has a domain with acidic amino acid residues that interfere with the base pairs in the centre of the junction. This forces the base pairs apart so that they can re-anneal with base pairs on the homologous strands.
In order for migration to occur, RuvA must be associated with RuvB and ATP. RuvB has the ability to hydrolyze ATP, driving the movement of the branch point. RuvB is a hexamer with helicase activity, and also binds the DNA. As ATP is hydrolyzed, RuvB rotates the recombined strands while pulling them out of the junction, but does not separate the strands as helicase would.
The final step in branch migration is called resolution and requires the protein RuvC. The protein is a dimer, and will bind to the Holliday junction when it takes on the stacked X form. The |
https://en.wikipedia.org/wiki/Quartz%20crystal%20microbalance%20with%20dissipation%20monitoring | Within surface science, a quartz crystal microbalance with dissipation monitoring (QCM-D) is a type of quartz crystal microbalance (QCM) based on the ring-down technique. It is used in interfacial acoustic sensing. Its most common application is the determination of a film thickness in a liquid environment (such as the thickness of an adsorbed protein layer). It can be used to investigate further properties of the sample, most notably the layer's softness.
Method
Ring-down as a method to interrogate acoustic resonators was established in 1954. In the context of the QCM, it was described by Hirao et al. and Rodahl et al. The active component of a QCM is a thin quartz crystal disk sandwiched between a pair of electrodes. The application of an AC voltage over the electrodes causes the crystal to oscillate at its acoustic resonance frequency. When the AC voltage is turned off, the oscillation decays exponentially ("rings down"). This decay is recorded and the resonance frequency (f) and the energy dissipation factor (D) are extracted. D is defined as the loss of energy per oscillation period divided by the total energy stored in the system. D is equal to the resonance bandwidth divided by the resonance frequency. Other QCM instruments determine the bandwidth from the conductance spectra. Being a QCM, the QCM-D works in real-time, does not need labeling, and is surface-sensitive. Current QCM-D equipment enables measuring of more than 200 data points per second.
Changes in the resonance frequency (Δf) are primarily related to mass uptake or release at the sensor surface. When employed as a mass sensor, the instrument has a sensitivity of about 0.5 ng/cm2 according to the manufacturer. Changes in the dissipation factor (ΔD) are primarily related to the viscoelasticity (softness). The softness, in turn, often is related to structural changes of the film adhering at the sensor surface.
Mass sensor
When operated as a mass sensor, the QCM-D is often used to study m |
https://en.wikipedia.org/wiki/Flags%20of%20international%20organizations | This article contains a list of flags of international organizations.
Global
Transcontinental
Africa
Americas
Asia
Europe
Oceania
Flags
Vexillology
International organizations |
https://en.wikipedia.org/wiki/Benjamin%20Kagan | Veniamin Fyodorovich Kagan (; 10 March 1869 – 8 May 1953) was a Russian and Soviet mathematician and expert in geometry. He is the maternal grandfather of mathematicians Yakov Sinai and Grigory Barenblatt.
Biography
Kagan was born in Shavli, in the Kovno Governorate of the Russian Empire (now Šiauliai, Lithuania) in 1869, to a poor Lithuanian Jewish family. In 1871 his family moved to Yekaterinoslav (now Dnipro), where he grew up. Kagan entered the Imperial Novorossiya University in Odesa in 1887, but was expelled for revolutionary activities in 1889. He was put on probation and sent back to Yekaterinoslav. He studied mathematics on his own and in 1892 passed the state exam at Kyiv University.
In 1894 Kagan moved to Saint Petersburg where he continued his studies with Andrey Markov and Konstantin Posse. They tried to help him to obtain an academic position, but Kagan's Jewish background was an obstacle. Only in 1897 was he allowed to become a dozent at the Imperial Novorossiya University, where he continued to work until 1923. His students in the theory of relativity class he taught in 1921-22 included Nikolai Papaleksi, Alexander Frumkin and Igor Tamm.
Kagan worked at Moscow State University where he held the Geometry Chair from 1923 till 1952.
In 1924 he joined Otto Schmidt in drawing up plans for the Great Soviet Encyclopedia.
Mathematical work
He published over 100 mathematical papers in different parts of geometry, particularly on hyperbolic geometry and on Riemannian geometry. He received the Stalin Prize in 1943. He founded the science publisher Mathesis in Odesa. He was a director of the mathematics and natural sciences department of the Great Soviet Encyclopedia. He wrote a definitive biography of Nikolai Lobachevsky and edited his collected works (5 volumes, 1946–1951).
Kagan's doctoral students include Viktor Wagner and Isaak Yaglom.
Trivia
He's a minor character in The Fourth Prose (1930) by Osip Mandelstam.
External links
Biography – in t |
https://en.wikipedia.org/wiki/Abivax | Abivax SA is a French clinical-stage, publicly traded biotechnology company harnessing the immune system to develop novel treatments against inflammatory diseases, viral diseases and cancer. The company is headquartered in Paris, France and closely cooperates with the CNRS Collaborative Laboratory in Montpellier, France.
Founding and IPO
Abivax has been founded in December 2013 in Paris under the leadership of Truffle Capital by Phillipe Pouletty, co-founder and chairman of the board.
In 2015, Abivax launched its initial public offering on the stock market Euronext in Paris, raising EUR 57.7m, a record amount for a French biotechnology company on the Euronext in Paris.
Initially, Abivax focused on the development of a novel treatment in HIV with lead drug candidate ABX464. As the molecule showed a strong anti-inflammatory effect in preclinical models, Abivax decided to conduct a Phase 2a clinical study in ulcerative colitis, an inflammatory bowel disease (IBD). Based on the promising results of this clinical study in ulcerative colitis, the company decided to shift its focus towards the treatment of chronic inflammatory diseases.
Pipeline
ABX464 in inflammatory diseases
Abivax focuses on the treatment of inflammatory diseases, namely ulcerative colitis (UC), Crohn’s disease (CD), rheumatoid arthritis (RA) and also COVID-19, where the hyper-inflammation syndrome is known to be the cause of the severe form of the disease. Its lead drug candidate, ABX464, is an oral, first-in-class, small molecule that has demonstrated safety and tolerability as well as profound anti-inflammatory activity in preclinical as well as clinical trials in UC and HIV.
ABX464 for the treatment of ulcerative colitis
ABX464 is currently being tested in a clinical Phase 2b trial in patients with moderate-to-severe ulcerative colitis, composed of an induction and a maintenance study, conducted in 15 European countries, Canada and the US. The previously conducted Phase 2a induction and |
https://en.wikipedia.org/wiki/2006%20North%20American%20E.%20coli%20O157%3AH7%20outbreaks | In 2006, there were several outbreaks of foodborne illness from spinach and lettuce contaminated by E. coli O157:H7.
Spinach
The initial outbreak occurred in September 2006 and its probable origin was an Angus cattle ranch that had leased land to a spinach grower (growing under organic practices). At least 205 consumer illnesses and three deaths have been attributed to the tainted produce.
Lettuce
Taco Bell
In December 2006, Taco Bell restaurants in four Northeastern states emerged as a common link among 71 sickened people across five states, 52 of whom were ultimately confirmed by the Centers for Disease Control to have tested positive the same E. coli strain. A total of 33 people in New Jersey, 22 in New York, 13 in Pennsylvania, 2 in Delaware, and 1 in South Carolina fell ill, according to the CDC.
The four states with Taco Bell restaurants where these consumers were confirmed to have eaten were in New Jersey, New York, Pennsylvania, and Delaware. (The patient from South Carolina ate at a Taco Bell restaurant in Pennsylvania).
Of the 71 reported cases, 53 were hospitalized and 8 developed a type of kidney failure called hemolytic–uremic syndrome. According to the CDC, illness onset dates ranged from November 20 to December 6.
On December 7, 2006, an initial investigation attributed the outbreak to green onions, which had been supplied to the Taco Bell restaurants by a single McLane Company distribution center in Burlington Township, New Jersey.
Tainted green onions may have proven a ready culprit in part because of their involvement in at least one widely reported prior outbreak of E. coli. In 2003, green onions were suspected as the cause of a foodborne illness involving the Chi-Chi's restaurant chain in western Pennsylvania that killed 4 people and sickened 660.
After further investigation, Taco Bell determined that the cause of the problem was with lettuce, not green onions, and switched produce suppliers in the New York, New Jersey, Pennsylvania, |
https://en.wikipedia.org/wiki/Federation%20of%20Agrifood | The Federation of Agrifood (, FEAGRA) was a trade union representing workers in food production and processing in Spain.
The union was established in 2000, when the Federation of Food Processing merged with the Federation of Agriculture. Like both its predecessors, it affiliated to the Workers' Commissions. In 2016, it merged into the Federation of Industry. |
https://en.wikipedia.org/wiki/Artin%E2%80%93Tate%20lemma | In algebra, the Artin–Tate lemma, named after Emil Artin and John Tate, states:
Let A be a commutative Noetherian ring and commutative algebras over A. If C is of finite type over A and if C is finite over B, then B is of finite type over A.
(Here, "of finite type" means "finitely generated algebra" and "finite" means "finitely generated module".) The lemma was introduced by E. Artin and J. Tate in 1951 to give a proof of Hilbert's Nullstellensatz.
The lemma is similar to the Eakin–Nagata theorem, which says: if C is finite over B and C is a Noetherian ring, then B is a Noetherian ring.
Proof
The following proof can be found in Atiyah–MacDonald. Let generate as an -algebra and let generate as a -module. Then we can write
with . Then is finite over the -algebra generated by the . Using that and hence is Noetherian, also is finite over . Since is a finitely generated -algebra, also is a finitely generated -algebra.
Noetherian necessary
Without the assumption that A is Noetherian, the statement of the Artin–Tate lemma is no longer true. Indeed, for any non-Noetherian ring A we can define an A-algebra structure on by declaring . Then for any ideal which is not finitely generated, is not of finite type over A, but all conditions as in the lemma are satisfied. |
https://en.wikipedia.org/wiki/Cleaved%20amplified%20polymorphic%20sequence | The cleaved amplified polymorphic sequence (CAPS) method is a technique in molecular biology for the analysis of genetic markers. It is an extension to the restriction fragment length polymorphism (RFLP) method, using polymerase chain reaction (PCR) to more quickly analyse the results.
Like RFLP, CAPS works on the principle that genetic differences between individuals can create or abolish restriction endonuclease restriction sites, and that these differences can be detected in the resulting DNA fragment length after digestion.
In the CAPS method, PCR amplification is directed across the altered restriction site, and the products digested with the restriction enzyme. When fractionated by agarose or polyacrylamide gel electrophoresis, the digested PCR products will give readily distinguishable patterns of bands. Alternatively, the amplified segment can be analyzed by allele-specific oligonucleotide (ASO) probes, a process that can often be done by a simple dot blot.
See also
RFLP |
https://en.wikipedia.org/wiki/Brisavirus | Brisavirus (isolate LC KY052047) is a species of Redondoviridae in the genus Torbevirus. Brisa- is from the Spanish word for "Breeze", which refers to their isolation from the human respiratory tract. It was discovered in a throat swab in a male traveler who presented with fever, enlarged adenoids, flushed skin and myalgia after testing negative for other viruses. Brisavirus like other viruses in the Redondoviridae family, are present and putatively replicate in the oro-respiratory tract. They are associated in patients with critical illness and periodontitis.
Genome
Brisavirus has a CRESS DNA genome with 3 open reading frames that are inversely oriented that encode for the capsid and Replication-associated protein protein with a small and larger intergenic region. They replicate using rolling-circle replication like other CRESS viruses. By using metagenomic analysis, researchers found that the encoded proteins were most similar to porcine stool-associated circular virus 5 isolate CP33 (PoSCV5). |
https://en.wikipedia.org/wiki/Osmotic%20shock | Osmotic shock or osmotic stress is physiologic dysfunction caused by a sudden change in the solute concentration around a cell, which causes a rapid change in the movement of water across its cell membrane. Under hypertonic conditions - conditions of high concentrations of either salts, substrates or any solute in the supernatant - water is drawn out of the cells through osmosis. This also inhibits the transport of substrates and cofactors into the cell thus “shocking” the cell. Alternatively, under hypotonic conditions - when concentrations of solutes are low - water enters the cell in large amounts, causing it to swell and either burst or undergo apoptosis.
All organisms have mechanisms to respond to osmotic shock, with sensors and signal transduction networks providing information to the cell about the osmolarity of its surroundings; these signals activate responses to deal with extreme conditions. Cells that have a cell wall tend to be more resistant to osmotic shock because their cell wall enables them to maintain their shape. Although single-celled organisms are more vulnerable to osmotic shock, since they are directly exposed to their environment, cells in large animals such as mammals still suffer these stresses under some conditions. Current research also suggests that osmotic stress in cells and tissues may significantly contribute to many human diseases.
In eukaryotes, calcium acts as one of the primary regulators of osmotic stress. Intracellular calcium levels rise during hypo-osmotic and hyper-osmotic stresses.
Recovery and tolerance mechanisms
For hyper-osmotic stress
Calcium plays a large role in the recovery and tolerance for both hyper and hypo-osmotic stress situations. Under hyper-osmotic stress conditions, increased levels of intracellular calcium are exhibited. This may play a crucial role in the activation of second messenger pathways.
One example of a calcium activated second messenger molecule is MAP Kinase Hog-1. It is activated under |
https://en.wikipedia.org/wiki/SBK3 | SH3 Domain Binding Kinase Family Member 3 is an enzyme that in humans is encoded by the SBK3 gene (also known as SGK110). SBK3 is a member of the serine/threonine protein kinase family. The SBK3 protein is known to exhibit transferase activity, especially phosphotransferase activity, and tyrosine kinase activity. It is well-conserved throughout mammalian organisms and has two paralogs: SBK1 and SBK2.
Gene
SBK3 is found on the minus strand of chromosome 19 in humans: 19q13.42. Its reference isoform consists of 4,985 bases. Nearby genes include SBK2, a paralog to SBK3, as well as SSC5D, ZNF579, and FIZ1.
Transcripts
SBK3 has five exons; however, only four are included in the final mRNA transcript. SBK3 is found to have one isoform outside of its typical transcript. The reference isoform does not include exon 2 and isoform X1 does not include exon 1.
Protein
General properties
SBK3's reference protein has a predicted molecular mass of 38.5 kDa and an isoelectric point of 4.71 pI. SBK3 has a significantly higher presence of proline amino acids than most proteins, which aligns with its proline-rich compositional bias that spans residues 189-278. The exact function of this proline-rich region in SBK3 is yet to be determined; however, prior research states that it's the region in which the SH3 domain of interacting proteins binds to SBK3.
Primary sequence
As previously stated, SBK3's reference protein is made up of 359 amino acids. The polypeptide chain that results from the translation of SBK3 into the SBK3 protein is shown below. A non-canonical polyadenylation signal ‘TATAAA’ is found 622 bases downstream from the stop codon.
Domains
SBK3 has a large conserved catalytic domain specific to the protein kinase superfamily. Nineteen ATP-binding sites found in SBK3’s paralog, SBK1, are all conserved in SBK3. The tyrosine motif exists in SBK3 (residues 44-233) and is found to overlap the conserved protein kinase superfamily domain (residues 49-208). SBK3's active |
https://en.wikipedia.org/wiki/Sunbury%20Research%20Centre | The Sunbury Research Centre -- also known as ICBT Sunbury—is a main research institute of BP in north-east Surrey.
History
It began in 1917 as the Sunbury Research Station. Research began with the employment of two chemists to look into the viscosity of fuel oil for the Navy in the First World War, and the production of toluene. In the 1920s research took place into cracking, at the plant at Uphall in Scotland (West Lothian). The first new building opened in July 1931. 76 staff were there in 1929, 99 in 1934 and 197 in 1939.
By the 1950s, BP Research was in a 39-acre site in Sunbury. Geophysical research had also taken place at Kirklington Hall Research Station in Nottinghamshire, until 1957. Around 1958, the site was expanded with a new Physics laboratory and five other buildings. A Linear electron accelerator was installed. By early 1958, Kirklington Hall had been sold.
Products that the British Petroleum Company made in the 1950s were BP Motor Spirit and BP Energol (visco-static motor oil). But Britain would not produce much oil of its own until the mid-1970s when North Sea oil arrived at the Forties Oil Field.
Construction
Three new buildings were built from 1998 as part of Phase 1. Since 2001, four new buildings were built as part of Phase 2.
Structure
It is situated off the A244 (via the A308) in the north of Sunbury-on-Thames, and Surrey, on the Surrey boundary with London. To the east nearby is Sunbury Common.
The retail division of BP UK is at Witan Gate House. BP employs around 15,000 people in the UK.
It has an enhanced oil recovery laboratory.
See also
Castrol Technology Centre
Oil fields operated by BP
Peter Mather (businessman), Head of BP UK
National Physical Laboratory (United Kingdom) |
https://en.wikipedia.org/wiki/Escherichia%20coli%20NC101 | Escherichia coli (AIEC) NC101 is a mouse isolate, serotype O2:H6/41, that is pro-carcinogenic, adherent-invasive (AIEC), probiotic strain of Escherichia coli, a species of bacteria that thrives in the intestines of mammals. NC101 has also been identified as a nicotinic acid (NA) auxotroph, a pathobiont, which is an organism that is harmful under certain circumstances, and is an important, relevant model organism that demonstrates how susceptible individuals may produce inappropriate immune responses to seemingly benign intestinal E. coli.
History
NC101 was first isolated and found from a specific pathogen-free wild-type mouse at the North Carolina State University between 2004 and 2005. Sequencing of NC101 showed it has a missense mutation in nadA, a gene that encodes for quinolinate synthase A, which is necessary for de novo nicotinamide adenine dinucleotide (NAD) biosynthesis.
Effects
E. coli NC101 has been found to promote carcinoma specifically, mucinous adenocarcinoma, in while performing experiments in azoxymethane treated mice. The findings of the study found "...tumorigenesis by altering microbial composition and inducing the expansion of microorganisms with genotoxic capabilities." The frequency of specific E. coli strains like NC101 in laboratory mouse colonies is currently unknown.
See also
Escherichia coli
Escherichia
Pseudomonadota
Enterobacteriacae |
https://en.wikipedia.org/wiki/IPadOS%2016 | iPadOS 16 is the fourth major release of the iPadOS operating system developed by Apple for its iPad line of tablet computers. The successor to iPadOS 15, it was announced at the company's Worldwide Developers Conference (WWDC) on June 6, 2022, along with iOS 16, macOS Ventura, watchOS 9, and tvOS 16. It received numerous new features, improving multitasking and many other aspects of the operating system, most notably on iPads with Apple's M1 SoC and later.
The public beta of iPadOS 16 was released on July 11, 2022. The public version of iPadOS 16 was released on October 24, 2022 as iPadOS 16.1.
iPadOS 16 is the final version of iPadOS that supports the first-generation iPad Pro and iPads without Apple Pencil compatibility, especially the fifth-generation iPad, as its successor, iPadOS 17, drops support for those models.
Features
Freeform
Freeform is a whiteboard app that lets users collaborate together in real time. It was released with iPadOS 16.2.
Weather
For the first time, Apple's Weather app is available on iPad. It was originally only available on iPhone and iPod Touch.
Lock screen
The Lock Screen has a new font and displays the date above the time to match iOS 16, but lacks the new customization features, which were later added in iPadOS 17.
Passkeys
iPads will now be able to sign into websites that implement WebAuthn using just the user’s passcode or biometrics.
Stage Manager
On iPads with Apple A12X Bionic, Apple A12Z Bionic, Apple M1 and Apple M2 processors, Stage Manager displays up to four apps at a time in adjustable windows. In addition, on iPads with Apple M1 and later, external displays are now driven using Stage Manager instead of screen mirroring, enabling display scaling on external displays.
Display scaling mode
On iPads with Apple M1 processors and later, and iPad Pro 11-inch with Apple A12X Bionic and A12Z Bionic processors, Display scaling mode allows more view space in apps by increasing the pixel density of the display.
Referen |
https://en.wikipedia.org/wiki/Mathematical%20psychology | Mathematical psychology is an approach to psychological research that is based on mathematical modeling of perceptual, thought, cognitive and motor processes, and on the establishment of law-like rules that relate quantifiable stimulus characteristics with quantifiable behavior (in practice often constituted by task performance). The mathematical approach is used with the goal of deriving hypotheses that are more exact and thus yield stricter empirical validations. There are five major research areas in mathematical psychology: learning and memory, perception and psychophysics, choice and decision-making, language and thinking, and measurement and scaling.
Although psychology, as an independent subject of science, is a more recent discipline than physics, the application of mathematics to psychology has been done in the hope of emulating the success of this approach in the physical sciences, which dates back to at least the seventeenth century. Mathematics in psychology is used extensively roughly in two areas: one is the mathematical modeling of psychological theories and experimental phenomena, which leads to mathematical psychology, the other is the statistical approach of quantitative measurement practices in psychology, which leads to psychometrics.
As quantification of behavior is fundamental in this endeavor, the theory of measurement is a central topic in mathematical psychology. Mathematical psychology is therefore closely related to psychometrics. However, where psychometrics is concerned with individual differences (or population structure) in mostly static variables, mathematical psychology focuses on process models of perceptual, cognitive and motor processes as inferred from the 'average individual'. Furthermore, where psychometrics investigates the stochastic dependence structure between variables as observed in the population, mathematical psychology almost exclusively focuses on the modeling of data obtained from experimental paradigms and is ther |
https://en.wikipedia.org/wiki/Jingjing%20and%20Chacha | Jingjing and Chacha (警警 and 察察, a pun on the Chinese word for police, ) are the cartoon mascots of the Internet Surveillance Division of the Public Security Bureau in Shenzhen, People's Republic of China. Debuting on January 22, 2006, they are used to, amongst other things, inform Chinese Internet users what is and is not legal to consult or write on the Chinese Internet. According to the director of the Shenzhen Internet police, "[we published] the image of Internet Police in the form of a cartoon [...] to let all internet users know that the Internet is not a place beyond of law [and that] the Internet Police will maintain order in all online behavior."
The Shenzhen police plan to place images of the two characters on the main page of all Shenzhen websites and bulletin board systems, creating an online 'police presence' that works to remind citizens to monitor their own behavior in accordance with the Chinese law, much as a visible police presence does in the real world. Clicking on the images will take a user to either of the characters' own personal webspace, where Chinese Internet users can learn about the laws and regulations related to Internet, keep up-to-date on the newest Internet policies, and submit questions to Jingjing and Chacha live through the instant messaging service Tencent QQ or through their blogs. In addition to engaging the public on Internet censorship-related issues, they also handle cases relating to computer viruses, computer crimes, and other such matters. As of January 2006, there were six police officers assigned to carry out these duties.
In August 2007, Beijing police announced a similar campaign using animated officers. The Beijing version of the characters will appear every half-hour on 13 of China's top web portals and display messages about Internet laws and conduct.
Criticism
Despite these extra functions, the China Digital Times reported that it was told by an official at the Bureau that the main purpose of Jingjing and Chac |
https://en.wikipedia.org/wiki/Satao%20%28elephant%29 | Satao (c. 1968 – 30 May 2014) was one of Kenya's largest African elephants. He was known as a tusker because his tusks were so long that they almost touched the ground. The Tsavo Trust announced that Satao was killed by poachers using a poisoned arrow on 30 May 2014.
Background
Satao was an African elephant that lived in Tsavo East National Park, one of the largest wildlife parks in the world with a large population of elephants. He was thought to have been born during the late 1960s and to have been at least 45 years old when he was killed. He was estimated to be one of the largest elephants in the world at the time of his death and has been described as one of Kenya's most iconic and well-known tuskers (i.e., male elephants with tusks that almost reach the ground). Satao's tusks were over long and he was estimated to be the largest of the few remaining tuskers living in Kenya. More than half of all of the remaining African big tuskers are in Kenya.
Elephant ivory poaching is a widespread problem in Africa. In 2013, over 20,000 African elephants were killed for their ivory. The slaughter of African elephants is driven by the black market value of elephant ivory. The illicit trade in ivory is primarily in Asia where ivory sells for several thousands of dollars per kilogram. Satao's tusks were estimated to weigh more than each.
Since 2007, the illegal trade in ivory had doubled. While China is the largest market, the United States, Thailand, Vietnam, and the Philippines are also top markets for illegal ivory. The increase in poaching is driven in large part by organised crime and rebel groups seeking ways to fund insurgencies in Africa.
Due to the great value of his tusks on the black market, Satao had been under nearly constant surveillance by the Kenya Wildlife Service (KWS) and the Tsavo trust for the 18 months prior to June 2014. He typically remained in a small area of the park, but had started roaming into areas of the park where poaching was high. Beca |
https://en.wikipedia.org/wiki/Grayanotoxin | Grayanotoxins are a group of closely related neurotoxins named after Leucothoe grayana, a plant native to Japan originally named for 19th century American botanist Asa Gray. Grayanotoxin I (grayanotaxane-3,5,6,10,14,16-hexol 14-acetate) is also known as andromedotoxin, acetylandromedol, rhodotoxin and asebotoxin. Grayanotoxins are produced by Rhododendron species and other plants in the family Ericaceae. Honey made from the nectar and so containing pollen of these plants also contains grayanotoxins and is commonly referred to as mad honey. Consumption of the plant or any of its secondary products, including mad honey, can cause a rare poisonous reaction called grayanotoxin poisoning, mad honey disease, honey intoxication, or rhododendron poisoning. It is most frequently produced and consumed in regions of Nepal and Turkey as a recreational drug and traditional medicine.
Origin
Grayanotoxins are produced by plants in the family Ericaceae, specifically members of the genera Rhododendron, Pieris, Agarista and Kalmia. The genus Rhododendron alone encompasses over 750 species that grow around the world in parts of Europe, North America, Japan, Nepal and Turkey. They can grow at a variety of altitudes ranging from sea level to more than three kilometers above. While many of these species contain grayanotoxins, only a few contain significant levels. Species with high concentrations of grayanotoxins such as R. ponticum, R. flavum and R. luteum are most commonly found in Nepal and regions of Turkey bordering the Black Sea.
Nearly all parts of grayanotoxin-producing rhododendrons contain the molecule, including the stem, leaves, flower, pollen and nectar. Grayanotoxins can also be found in secondary plant products such as honey, labrador tea, cigarettes and herbal medicines.
Chemical structure
Grayanotoxins are low molecular weight hydrophobic compounds. They are structurally characterized as polyhydroxylated cyclic diterpenes. The base structure is a 5/7/6/5 ring syste |
https://en.wikipedia.org/wiki/Sequence%20point | In C and C++, a sequence point defines any point in a computer program's execution at which it is guaranteed that all side effects of previous evaluations will have been performed, and no side effects from subsequent evaluations have yet been performed. They are a core concept for determining the validity of and, if valid, the possible results of expressions. Adding more sequence points is sometimes necessary to make an expression defined and to ensure a single valid order of evaluation.
With C11 and C++11, usage of the term sequence point has been replaced by sequencing. There are three possibilities:
An expression's evaluation can be sequenced before that of another expression, or equivalently the other expression's evaluation is sequenced after that of the first.
The expressions' evaluation is indeterminately sequenced, meaning one is sequenced before the other, but which is unspecified.
The expressions' evaluation is unsequenced.
The execution of unsequenced evaluations can overlap, leading to potentially catastrophic undefined behavior if they share state. This situation can arise in parallel computations, causing race conditions, but undefined behavior can also result in single-threaded situations. For example, a[i] = i++; (where is an array and is an integer) has undefined behavior.
Examples of ambiguity
Consider two functions f() and g(). In C and C++, the + operator is not associated with a sequence point, and therefore in the expression f()+g() it is possible that either f() or g() will be executed first. The comma operator introduces a sequence point, and therefore in the code f(),g() the order of evaluation is defined: first f() is called, and then g() is called.
Sequence points also come into play when the same variable is modified more than once within a single expression. An often-cited example is the C expression i=i++, which apparently both assigns i its previous value and increments i. The final value of i is ambiguous, because, depending on |
https://en.wikipedia.org/wiki/Qwerty%20effect | The QWERTY effect (or qwerty effect) emphasizes ways that modern keyboard layouts have influenced human language, naming preferences and behavior.
The Wubi effect references the same process of influence driven by autocomplete, Chinese input methods for computers (such as the Wubi method), and real time input suggestions from search engines based on current events. |
https://en.wikipedia.org/wiki/Friedberg%20numbering | In computability theory, a Friedberg numbering is a numbering (enumeration) of the set of all uniformly recursively enumerable sets that has no repetitions: each recursively enumerable set appears exactly once in the enumeration (Vereščagin and Shen 2003:30).
The existence of such numberings was established by Richard M. Friedberg in 1958 (Cutland 1980:78). |
https://en.wikipedia.org/wiki/Sporidia | Sporidia are result of homokaryotic smut fungi (which are not pathogenic), asexual reproduction through the process of budding.
Thus far, this has only been observed in vitro. |
https://en.wikipedia.org/wiki/Floating-point%20error%20mitigation | Floating-point error mitigation is the minimization of errors caused by the fact that real numbers cannot, in general, be accurately represented in a fixed space. By definition, floating-point error cannot be eliminated, and, at best, can only be managed.
Huberto M. Sierra noted in his 1956 patent "Floating Decimal Point Arithmetic Control Means for Calculator":
The Z1, developed by Konrad Zuse in 1936, was the first computer with floating-point arithmetic and was thus susceptible to floating-point error. Early computers, however, with operation times measured in milliseconds, were incapable of solving large, complex problems and thus were seldom plagued with floating-point error. Today, however, with supercomputer system performance measured in petaflops, floating-point error is a major concern for computational problem solvers.
The following sections describe the strengths and weaknesses of various means of mitigating floating-point error.
Numerical error analysis
Though not the primary focus of numerical analysis, numerical error analysis exists for the analysis and minimization of floating-point rounding error.
Monte Carlo arithmetic
Error analysis by Monte Carlo arithmetic is accomplished by repeatedly injecting small errors into an algorithm's data values and determining the relative effect on the results.
Extension of precision
Extension of precision is the use of larger representations of real values than the one initially considered. The IEEE 754 standard defines precision as the number of digits available to represent real numbers. A programming language can include single precision (32 bits), double precision (64 bits), and quadruple precision (128 bits). While extension of precision makes the effects of error less likely or less important, the true accuracy of the results are still unknown.
Variable length arithmetic
Variable length arithmetic represents numbers as a string of digits of variable length limited only by the memory available. V |
https://en.wikipedia.org/wiki/Rotational%20Brownian%20motion%20%28astronomy%29 | In astronomy, rotational Brownian motion is the random walk in orientation of a binary star's orbital plane, induced by gravitational perturbations from passing stars.
Theory
Consider a binary that consists of two massive objects (stars, black holes etc.) and that is embedded in a stellar system containing a large number of stars. Let and be the masses of the two components of the binary whose total mass is . A field star that approaches the binary with impact parameter and velocity passes a distance from the binary, where
the latter expression is valid in the limit that gravitational focusing dominates the encounter rate. The rate of encounters with stars that interact strongly with the binary, i.e. that satisfy , is approximately where and are the number density and velocity dispersion of the field stars and is the semi-major axis of the binary.
As it passes near the binary, the field star experiences a change in velocity of order
,
where is the relative velocity of the two stars in the binary.
The change in the field star's specific angular momentum with respect to the binary, , is then Δl ≈ a Vbin. Conservation of angular momentum implies that the binary's angular momentum changes by Δlbin ≈ -(m/μ12)Δl where m is the mass of a field star and μ12 is the binary reduced mass. Changes in the magnitude of lbin correspond to changes in the binary's orbital eccentricity via the relation e = 1 - lb2/GM12μ12a. Changes in the direction of lbin correspond to changes in the orientation of the binary, leading to rotational diffusion. The rotational diffusion coefficient is
where ρ = mn is the mass density of field stars.
Let F(θ,t) be the probability that the rotation axis of the binary is oriented at angle θ at time t. The evolution equation for F is
If <Δξ2>, a, ρ and σ are constant in time, this becomes
where μ = cos θ and τ is the time in units of the relaxation time trel, where
The solution to this equation states that the expectation value |
https://en.wikipedia.org/wiki/Control%20%28optimal%20control%20theory%29 | In optimal control theory, a control is a variable chosen by the controller or agent to manipulate state variables, similar to an actual control valve. Unlike the state variable, it does not have a predetermined equation of motion. The goal of optimal control theory is to find some sequence of controls (within an admissible set) to achieve an optimal path for the state variables (with respect to a loss function).
A control given as a function of time only is referred to as an open-loop control. In contrast, a control that gives optimal solution during some remainder period as a function of the state variable at the beginning of the period is called a closed-loop control.
See also
Control loop |
https://en.wikipedia.org/wiki/Rhapsody%20%28operating%20system%29 | Rhapsody is an operating system that was developed by Apple Computer after its purchase of NeXT in the late 1990s. It is the fifth major release of the Mach-based operating system that was developed at NeXT in the late 1980s, previously called OPENSTEP and NEXTSTEP. Rhapsody was targeted to developers for a transition period between the Classic Mac OS and Mac OS X. Rhapsody represented a new and exploratory strategy for Apple, more than an operating system, and runs on x86-based PCs and on Power Macintosh.
Rhapsody's OPENSTEP based Yellow Box API frameworks were ported to Windows NT for creating cross-platform applications. Eventually, the non-Apple platforms were discontinued, and later versions consist primarily of the OPENSTEP operating system ported to Power Macintosh, merging the Copland-originated GUI of Mac OS 8 with that of OPENSTEP. Several existing classic Mac OS frameworks were ported, including QuickTime and AppleSearch. Rhapsody can run Mac OS 8 and its applications in a paravirtualization layer called Blue Box for backward compatibility during migration to Mac OS X.
Background
Naming
Rhapsody follows Apple's pattern through the 1990s of music-related codenames for operating system releases (see Rhapsody (music)). Apple had canceled its previous next-generation operating system strategy of Copland (named for American composer, Aaron Copland) and its pre-announced successor Gershwin (named for George Gershwin, composer of Rhapsody in Blue). Other musical code names include Harmony (Mac OS 7.6), Tempo (Mac OS 8), Allegro (Mac OS 8.5), and Sonata (Mac OS 9).
Previous attempts to develop a successor to the Classic Mac OS
In the mid-1990s, Mac OS was falling behind Windows. In 1993, Microsoft had introduced the next-generation Windows NT, which was a processor-independent, multiprocessing and multi-user operating system. At the time, Mac OS was still a single-user OS, and had gained a reputation for being unstable. Apple made several attempts to devel |
https://en.wikipedia.org/wiki/Ingress%20cancellation | Ingress cancellation is a method for removing narrowband noise from an electromagnetic signal using a digital filter. This type of filter is used on hybrid fiber-coaxial broadband networks.
If a carrier appears in the middle of the upstream data signal, ingress cancellation can remove the interfering carrier without causing packet loss.
Ingress cancellation also removes one or more carriers that are higher in amplitude than the data signal. Ingress cancellation eventually will break if the in-channel ingress gets too high. |
https://en.wikipedia.org/wiki/Elemental%20tetrad | The elemental tetrad is a conceptual framework used in game design. Based on mechanics, aesthetics, stories and technology.
Description
Mechanics describe the rules of the game, what players can and cannot do, while trying to achieve the game's goal and what happens when they try.
Story some sort of sequences of events that unfolds in a game and that can be linear and pre-scripted, or non-linear or even random.
Aesthetics define how the game looks, sounds and feels. Aesthetics has the most direct relationship to the player’s experience.
Technology is what makes the game work, as an essential medium in which other parts of tetrad work: where the aesthetics take place, in which the mechanics will occur, and through which the story will be told. |
https://en.wikipedia.org/wiki/Protoanemonin | Protoanemonin (sometimes called anemonol or ranunculol) is a toxin found in all plants of the buttercup family (Ranunculaceae). When the plant is wounded or macerated, the unstable glucoside found in the plant, ranunculin, is enzymatically broken down into glucose and the toxic protoanemonin. It is the lactone of 4-hydroxy-2,4-pentadienoic acid.
Contact with a wounded plant causes itch, rashes or blistering on contact with the skin or mucosa. Ingesting the toxin can cause nausea, vomiting, dizziness, spasms, acute hepatitis, jaundice, or paralysis.
When drying the plant, protoanemonin comes into contact with air and dimerizes to anemonin, which is further hydrolyzed to a non-toxic dicarboxylic acid.
Biological pathway |
https://en.wikipedia.org/wiki/Resistance-nodulation-cell%20division%20superfamily | Resistance-nodulation-division (RND) family transporters are a category of bacterial efflux pumps, especially identified in Gram-negative bacteria and located in the cytoplasmic membrane, that actively transport substrates. The RND superfamily includes seven families: the heavy metal efflux (HME), the hydrophobe/amphiphile efflux-1 (gram-negative bacteria), the nodulation factor exporter family (NFE), the SecDF protein-secretion accessory protein family, the hydrophobe/amphiphile efflux-2 family, the eukaryotic sterol homeostasis family, and the hydrophobe/amphiphile efflux-3 family. These RND systems are involved in maintaining homeostasis of the cell, removal of toxic compounds, and export of virulence determinants. They have a broad substrate spectrum and can lead to the diminished activity of unrelated drug classes if over-expressed. The first reports of drug resistant bacterial infections were reported in the 1940s after the first mass production of antibiotics. Most of the RND superfamily transport systems are made of large polypeptide chains. RND proteins exist primarily in gram-negative bacteria but can also be found in gram-positive bacteria, archaea, and eukaryotes.
Function
The RND protein dictates the substrate for the completed transport systems including: metal ions, xenobiotics or drugs. Transport of hydrophobic and amphiphilic compounds are carried out by the HAE-RND subfamily. While the efflux of heavy metals are preformed HME-RND.
Mechanism and structure
RND proteins are large and can include more than 1000 amino acid residues. They are generally composed of two homologous subunits (suggesting they arose as a result of an intragenic tandem duplication event that occurred in the primordial system prior to divergence of the family members) each containing a periplasmic loop adjacent to 12 transmembrane helices. Of the twelve helices there is a single transmembrane spanner (TMS) at the N-terminus followed by a large extracytoplasmic domain, then |
https://en.wikipedia.org/wiki/Fecundity%20selection | Fecundity selection, also known as fertility selection, is the fitness advantage resulting from selection on traits that increases the number of offspring (i.e. fecundity). Charles Darwin formulated the theory of fecundity selection between 1871 and 1874 to explain the widespread evolution of female-biased sexual size dimorphism (SSD), where females were larger than males.
Along with the theories of natural selection and sexual selection, fecundity selection is a fundamental component of the modern theory of Darwinian selection. Fecundity selection is distinct in that large female size relates to the ability to accommodate more offspring, and a higher capacity for energy storage to be invested in reproduction. Darwin's theory of fecundity selection predicts the following:
Fecundity depends on variation in female size, which is associated with fitness.
Strong fecundity selection favors large female size, which creates asymmetrical female-biased sexual size dimorphism.
Although sexual selection and fecundity selection are distinct, it still may be difficult to interpret whether sexual dimorphism in nature is due to fecundity selection, or to sexual selection. Examples of fecundity selection in nature include self-incompatibility flowering plants, where pollen of some potential mates are not effective in forming seed, as well as bird, lizard, fly, and butterfly and moth species that are spread across an ecological gradient.
Moreau-Lack's rule
Moreau (1944) suggested that in more seasonal environments or higher latitudes, fecundity depends on high mortality. Lack (1954) suggested differential food availability and management across latitudes play a role in offspring and parental fitness. Lack also highlighted that more opportunities for parents to collect food due to an increase in day-length towards the poles is an advantage. This means that moderately higher altitudes provide more successful conditions to produce more offspring. However, extreme day-lengths ( |
https://en.wikipedia.org/wiki/Z800%203DVisor | The Z800 3DVisor is a head-mounted display manufactured by eMagin since 2005.
Overview
The main part of the Z800 is a pair of OLED displays with magnifying lenses producing a 40-degree diagonal field of view for each eye, used to display stereoscopic images with a fixed resolution of 800x600 pixels, through the use of the nVidia stereo 3D drivers, or, using later firmware revisions, any source of alternating frames. The visor can also be used as a 2D portable monitor on computers not equipped with an nVidia video card, using another operating system, or Macintoshes.
The visor is equipped with a NEC TOKIN combined accelerometer/magnetometer/rate gyroscope 3-degrees of freedom motion sensor used to emulate mouse movements (typically to look around in first-person shooters), a pair of ear buds and an integrated microphone.
See also
Virtual reality
3D stereo view
External links
eMagin Website
Z800 3DVisor site
Linux Alpha Drivers
VR Viewer Headsets
Display technology
Multimodal interaction
Virtual reality headsets
Display devices |
https://en.wikipedia.org/wiki/Blood%20alcohol%20content | Blood alcohol content (BAC), also called blood alcohol concentration or blood alcohol level, is a measurement of alcohol intoxication used for legal or medical purposes; it is expressed as mass of alcohol per volume of blood. For example, a BAC of 0.10 (0.10% or one tenth of one percent) means that there is 0.10 g of alcohol for every 100 of blood, which is the same as 21.7 . A BAC of 0.0 is sober; in different countries the maximum permitted BAC when driving ranges from about 0.02% to 0.08%; BAC levels over 0.08% are considered impaired; above 0.40% is potentially fatal.
Effects by alcohol level
As BAC increases, the short-term effects of alcohol become more perceptible. At low levels of impairment (BAC 0.01–0.05%), people may experience mild relaxation and reduced social inhibition, along with impaired judgment and coordination. At moderate levels of impairment (BAC 0.06–0.20%), effects can include emotional swings, impaired vision, hearing, speech, and motor skills. Beginning at a BAC greater than 0.2%, people may experience urinary incontinence, vomiting, and symptoms of alcohol intoxication. At a BAC greater than 0.3%, people may experience total loss of consciousness and show signs of severe alcohol intoxication. A BAC of 0.4% or higher is potentially fatal and can result in a coma or respiratory failure.
Estimation
Direct measurement
Blood samples for BAC analysis are typically obtained by taking a venous blood sample from the arm. A variety of methods exist for determining blood-alcohol concentration in a blood sample. Forensic laboratories typically use headspace-gas chromatography combined with mass spectrometry or flame ionization detection, as this method is accurate and efficient. Hospitals typically use enzyme multiplied immunoassay, which measures the co-enzyme NADH. This method is more subject to error but may be performed rapidly in parallel with other blood sample measurements.
By breathalyzer
The amount of alcohol on the breath can be me |
https://en.wikipedia.org/wiki/Sialidase-1 | Sialidase-1, is a mammalian lysosomal neuraminidase enzyme which in humans is encoded by the NEU1 gene.
Function
The protein SIALIDASE-1 encoded by the NEU-1 gene encodes the lysosomal enzyme SIALIDASE-1, which cleaves terminal sialic acid residues from substrates such as glycoproteins and glycolipids. In the lysosome, this enzyme is part of a heterotrimeric complex together with beta-galactosidase and cathepsin A (the latter also referred to as 'protective protein'). Mutations in this gene can lead to sialidosis.
Clinical significance
Mutations in NEU1 leads to sialidosis, a rare lysosomal storage disease. Sialidase has also been shown to enhance recovery from spinal cord contusion injury when injected in rats.
Interactions
NEU1 has been shown to interact with Cathepsin A. |
https://en.wikipedia.org/wiki/Anne%20Condon | Anne Elizabeth Condon, is an Irish-Canadian computer scientist, professor, and former head of the Computer Science Department of the University of British Columbia. Her research focuses on computational complexity theory, DNA computing, and bioinformatics. She has also held the NSERC/General Motors Canada Chair for Women in Science and Engineering (CWSE) from 2004 to 2009, and has worked to improve the success of women in the sciences and engineering.
Biography
Condon did her undergraduate studies at University College Cork, earning a bachelor's degree in 1982. She moved to the University of Washington for her graduate studies, receiving her doctorate in 1987 under the supervision of Richard E. Ladner. She then joined the faculty at the University of Wisconsin–Madison, and remained there until her 1999 move to UBC.
Personal life
Condon is an avid triathlete, finishing 7th in her age-group (F55-59) during Ironman Canada 2019 and finishing 1st in her age group (F60-64) for Ironman Ireland 2022 in an impressive 12:10 hours timeframe. At the Ironman Hawaii 2022 she finished 18th in her age group (F60-64) with a time of 13:39. At the Ironman 70.3 Championship 2022, she finished 8th in her age group with a time of 5:55.
Awards and honors
Condon won an ACM Distinguished Dissertation award (honorable mention) for her thesis research. In 2010, the Association for Computing Machinery named her an ACM Fellow for contributions to complexity theory and leadership in advancing women in computing. In the same year, she also won the A. Nico Habermann Award of the Computing Research Association for "long-standing and impactful service toward the goal of increasing the participation of women in computer science research." She is also
a winner of the University College Cork Distinguished Alumna
Award, the University of Washington CSE Alumni
Achievement Award.,
and the 2012 University of Washington College of Engineering Diamond
Award for Distinguished Achievement in Academia. She |
https://en.wikipedia.org/wiki/Video%20Disk%20Control%20Protocol | Video Disk Control Protocol (VDCP) is a proprietary communications protocol primarily used in broadcast automation to control hard disk video servers for broadcast television. VDCP was originally developed by Louth Automation and is commonly called the Louth Protocol. At the time it was developed when Hewlett Packard (eventually sold to Pinnacle Systems) and Tektronix were both bringing to market the first of the VideoFile Servers to be used in the broadcast industry. They contacted Louth Automation who then designed the communications protocol basing it on Sony protocols of both the Sony LMS Storage Device and the Sony VTR. The principal work was carried out by Ken Louth at Louth Automation.
VDCP uses a tightly coupled master-slave methodology. The controlling device takes the initiative in communications between the controlling broadcast automation device and the controlled device (video disk). VDCP conforms to the Open Systems Interconnection (OSI) reference model.
VDCP is a serial communications protocol based on RS-422. It is derived from the Sony 9-Pin Protocol, an industry-standard protocol for control of professional broadcast VTRs that is used in online editing.
Full details of the protocol are available from Harris Broadcast, who acquired Louth in 2000.
External links
Harris Broadcast
NDCP Launch press release
Broadcast engineering
Television technology
Digital television
Television terminology |
https://en.wikipedia.org/wiki/Actor%20model%20and%20process%20calculi%20history | The actor model and process calculi share an interesting history and co-evolution.
Early work
The Actor model, first published in 1973, is a mathematical model of concurrent computation. The Actor model treats "Actors" as the universal primitives of concurrent digital computation: in response to a message that it receives, an Actor can make local decisions, create more Actors, send more messages, and determine how to respond to the next message received.
As opposed to the previous approach based on composing sequential processes, the Actor model was developed as an inherently concurrent model. In the Actor model sequentiality was a special case that derived from concurrent computation as explained in Actor model theory.
Robin Milner's initial published work on concurrency from the same year was also notable in that it positions mathematical semantics of communicating processes as a framework to understand a variety of interaction agents including the computer's interaction with memory. The framework of modelling was based on Scott's model of domains and as such was not based on sequential processes. His work differed from the Actor model in the following ways:
There are a fixed number of processes as opposed to the Actor model which allows the number of Actors to vary dynamically
The only quantities that can be passed in messages are integers and strings as opposed to the Actor model which allows the addresses of Actors to be passed in messages
The processes have a fixed topology as opposed to the Actor model which allows varying topology
Communication is synchronous as opposed to the Actor model in which an unbounded time can elapse between sending and receiving a message.
The semantics provided bounded nondeterminism unlike the Actor model with unbounded nondeterminism. However, with bounded nondeterminism is impossible for a server to guarantee service to its clients, i.e., a client might starve.
Milner later removed some of these restrictions in his |
https://en.wikipedia.org/wiki/RING%20finger%20domain | In molecular biology, a RING (short for Really Interesting New Gene) finger domain is a protein structural domain of zinc finger type which contains a C3HC4 amino acid motif which binds two zinc cations (seven cysteines and one histidine arranged non-consecutively). This protein domain contains 40 to 60 amino acids. Many proteins containing a RING finger play a key role in the ubiquitination pathway.
Zinc fingers
Zinc finger (Znf) domains are relatively small protein motifs that bind one or more zinc atoms, and which usually contain multiple finger-like protrusions that make tandem contacts with their target molecule. They bind DNA, RNA, protein and/or lipid substrates. Their binding properties depend on the amino acid sequence of the finger domains and of the linker between fingers, as well as on the higher-order structures and the number of fingers. Znf domains are often found in clusters, where fingers can have different binding specificities. There are many superfamilies of Znf motifs, varying in both sequence and structure.
They display considerable versatility in binding modes, even between members of the same class (e.g. some bind DNA, others protein), suggesting that Znf motifs are stable scaffolds that have evolved specialised functions. For example, Znf-containing proteins function in gene transcription, translation, mRNA trafficking, cytoskeleton organisation, epithelial development, cell adhesion, protein folding, chromatin remodelling and zinc sensing. Zinc-binding motifs are stable structures, and they rarely undergo conformational changes upon binding their target.
Some Zn finger domains have diverged such that they still maintain their core structure, but have lost their ability to bind zinc, using other means such as salt bridges or binding to other metals to stabilise the finger-like folds.
Function
Many RING finger domains simultaneously bind ubiquitination enzymes and their substrates and hence function as ligases. Ubiquitination in turn tar |
https://en.wikipedia.org/wiki/Womersley%20number | The Womersley number ( or ) is a dimensionless number in biofluid mechanics and biofluid dynamics. It is a dimensionless expression of the pulsatile flow frequency in relation to viscous effects. It is named after John R. Womersley (1907–1958) for his work with blood flow in arteries. The Womersley number is important in keeping dynamic similarity when scaling an experiment. An example of this is scaling up the vascular system for experimental study. The Womersley number is also important in determining the thickness of the boundary layer to see if entrance effects can be ignored.
The square root of this number is also referred to as Stokes number, , due to the pioneering work done by Sir George Stokes on the Stokes second problem.
Derivation
The Womersley number, usually denoted , is defined by the relation
where is an appropriate length scale (for example the radius of a pipe), is the angular frequency of the oscillations, and , , are the kinematic viscosity, density, and dynamic viscosity of the fluid, respectively. The Womersley number is normally written in the powerless form
In the cardiovascular system, the pulsation frequency, density, and dynamic viscosity are constant, however the Characteristic length, which in the case of blood flow is the vessel diameter, changes by three orders of magnitudes (OoM) between the aorta and fine capillaries. The Womersley number thus changes due to the variations in vessel size across the vasculature system. The Womersley number of human blood flow can be estimated as follows:
Below is a list of estimated Womersley numbers in different human blood vessels:
It can also be written in terms of the dimensionless Reynolds number (Re) and Strouhal number (St):
The Womersley number arises in the solution of the linearized Navier–Stokes equations for oscillatory flow (presumed to be laminar and incompressible) in a tube. It expresses the ratio of the transient or oscillatory inertia force to the shear force. When is s |
https://en.wikipedia.org/wiki/Posterior%20median%20sulcus%20of%20spinal%20cord | The posterior median sulcus is the posterior end of the posterior median septum of neuroglia of the spinal cord. The septum varies in depth from 4 to 6 mm, but diminishes considerably in the lower part of the spinal cord. |
https://en.wikipedia.org/wiki/Pleurotus%20eryngii | Pleurotus eryngii (also known as king trumpet mushroom, French horn mushroom, eryngi, king oyster mushroom, king brown mushroom, boletus of the steppes, trumpet royale, aliʻi oyster) is an edible mushroom native to Mediterranean regions of Europe, the Middle East, and North Africa, but also grown in many parts of Asia.
Description
Pleurotus eryngii is the largest species in the oyster mushroom genus, Pleurotus, which also contains the oyster mushroom Pleurotus ostreatus. It has a thick, meaty white stem and a small tan cap (in young specimens). Its natural range extends from the Atlantic Ocean through the Mediterranean Basin and Central Europe into Western Asia and India. Unlike other species of Pleurotus, which are primarily wood-decay fungi, the P. eryngii complex are also weak parasites on the roots of herbaceous plants, although they may also be cultured on organic wastes.
Taxonomy
Its species name is derived from the fact that it grows in association with the roots of Eryngium campestre or other Eryngium plants (English names: 'sea holly' or 'eryngo'). P. eryngii is a species complex, and a number of varieties have been described, with differing plant associates in the carrot family (Apiaceae).
Pleurotus eryngii var. eryngii (DC.) Quél 1872 – associated with Eryngium ssp.
Pleurotus eryngii var. ferulae (Lanzi) Sacc. 1887 – associated with Ferula communis
Pleurotus eryngii var. tingitanus Lewinsohn 2002 – associated with Ferula tingitana
Pleurotus eryngii var. elaeoselini Venturella, Zervakis & La Rocca 2000 – associated with Elaeoselinum asclepium
Pleurotus eryngii var. thapsiae Venturella, Zervakis & Saitta 2002 – associated with Thapsia garganica
Other specimens of P. eryngii have been reported in association with plants in the genera Ferulago, Cachrys, Laserpitium, and Diplotaenia, all in Apiaceae.
Molecular studies have shown Pleurotus nebrodensis to be closely related to, but distinct from, P. eryngii. Pleurotus fossulatus may be another closely re |
https://en.wikipedia.org/wiki/Segment%20routing | Segment routing, a form of computer networking, is a modern variant of source routing that is being developed within the SPRING and IPv6 working groups of the IETF. In a segment routed network, an ingress node may prepend a header to packets that contain a list of segments, which are instructions that are executed on subsequent nodes in the network. These instructions may be forwarding instructions, such as an instruction to forward a packet to a specific destination or interface.
Segment routing works either on top of a MPLS network or on an IPv6 network.
In an MPLS network, segments are encoded as MPLS labels. Under IPv6, a new header called a Segment Routing Header (SRH) is used. Segments in a SRH are encoded in a list of IPv6 addresses.
See also
Bang path
Dynamic Source Routing
Policy-based routing can also be used to route packets using their source addresses.
Scalable Source Routing |
https://en.wikipedia.org/wiki/Plasma%20Physics%20Laboratory%20%28Saskatchewan%29 | The Plasma Physics Laboratory at the University of Saskatchewan was established in 1959 by H. M. Skarsgard. Early work centered on research with a Betatron.
Facilities
STOR-1M
STOR-1M is Canada's first tokamak built in 1983. In 1987 STOR-1M was the world’s first demonstration of alternating current in a tokamak.
STOR-M
STOR-M stands for Saskatchewan Torus-Modified. STOR-M is a tokamak located at the University of Saskatchewan. STOR-M is a small tokamak (major radius = 46 cm, minor radius = 12.5 cm) designed for studying plasma heating, anomalous transport and developing novel tokamak operation modes and advanced diagnostics. STOR-M is capable of a 30–40 millisecond plasma discharge with a toroidal magnetic field of between 0.5 and 1 tesla and a plasma current of between 20 and 50 kiloamperes. STOR-M has also demonstrated improved confinement induced by a turbulent heating pulse, electrode biasing and compact torus injection. |
https://en.wikipedia.org/wiki/Shadow%20blister%20effect | The shadow blister effect is a visual phenomenon in which a shadow bulges (or blisters) as it approaches another.
The effect takes place when two objects are at varying distances between a non-point light source and a background upon which their shadows are cast. As the objects move transversely such that their shadows approach each other, the one nearest the light source begins blocking light from reaching the inside of the other object's penumbra, thereby expanding its umbra. This expansion of the further object's umbra continues until the umbras of both objects meet.
This effect can be demonstrated and understood using ray theory.
The shadow blister effect is commonly misconceived to be an illusion caused by the combining of the two object's penumbras, aided by factors such as diffraction, nonlinear response, and the eye's inability to differentiate between varying contrasts.
See Also
Black drop effect |
https://en.wikipedia.org/wiki/Visible%20Embryo%20Project | The Visible Embryo Project (VEP) is a multi-institutional, multidisciplinary research project originally created in the early 1990s as a collaboration between the Developmental Anatomy Center at the National Museum of Health and Medicine and the Biomedical Visualization Laboratory (BVL) at the University of Illinois at Chicago, "to develop software strategies for the development of distributed biostructural databases using cutting-edge technologies for high-performance computing and communications (HPCC), and to implement these tools in the creation of a large-scale digital archive of multidimensional data on normal and abnormal human development." This project related to BVL's other research in the areas of health informatics, educational multimedia, and biomedical imaging science. Over the following decades, the list of VEP collaborators grew to include over a dozen universities, national laboratories, and companies around the world.
An early (1993) goal of the project was to enable what it called "Spatial Genomics," to create tools and systems for three-dimensional morphological mapping of gene expression, to correlate data from the Human Genome Project with the multidimensional location of genomic expression activity within the morphological context of organisms. This led to the invention in the late 1990s by VEP collaborators of the first system for Spatial transcriptomics. Other areas that VEP researchers pioneered include early web technologies, cloud computing, blockchain, and virtual assistant technology.
Early history
The VEP was created in 1992 as a collaboration between the UIC Biomedical Visualization Laboratory, directed by Michael Doyle, and the Human Developmental Anatomy Center at the National Museum of Health and Medicine (NMHM), directed by Adrianne Noe. Doyle had been appointed to the oversight committee of the Visible Human Project at the National Library of Medicine, but it would be several years before that data would become available. Lo |
https://en.wikipedia.org/wiki/Jean%20Bartik | Jean Bartik ( Betty Jean Jennings; December 27, 1924 – March 23, 2011) was one of the original six programmers for the ENIAC computer.
Bartik studied mathematics in school then began work at the University of Pennsylvania, first manually calculating ballistics trajectories and then using ENIAC to do so. The other five ENIAC programmers were Betty Holberton, Ruth Teitelbaum, Kathleen Antonelli, Marlyn Meltzer, and Frances Spence. Bartik and her colleagues developed and codified many of the fundamentals of programming while working on the ENIAC, since it was the first computer of its kind.
After her work on ENIAC, Bartik went on to work on BINAC and UNIVAC, and spent time at a variety of technical companies as a writer, manager, engineer and programmer. She spent her later years as a real estate agent and died in 2011 from congestive heart failure complications.
Content-management framework Drupal's default theme, Bartik, is named in her honor.
Early life and education
Born Betty Jean Jennings in Gentry County, Missouri in 1924, she was the sixth of seven children. Her father, William Smith Jennings (1893–1971) was from Alanthus Grove, where he was a schoolteacher as well as a farmer. Her mother, Lula May Spainhower (1887–1988) was from Alanthus. Jennings had three older brothers, William (January 10, 1915) Robert (March 15, 1918); and Raymond (January 23, 1922); two older sisters, Emma (August 11, 1916) and Lulu (August 22, 1919), and one younger sister, Mable (December 15, 1928).
In her childhood, she would ride on horseback to visit her grandmother, who bought the young girl a newspaper to read every day and became a role model for the rest of her life. She began her education at a local one-room school, and gained local attention for her softball skill. In order to attend high school, she lived with her older sister in the neighboring town, where the school was located, and then began to drive every day despite being only 14. She graduated from Stanberry High |
https://en.wikipedia.org/wiki/Multifidelity%20simulation | Multifidelity (or multi-fidelity) methods leverage both low- and high-fidelity data in order to maximize the accuracy of model estimates, while minimizing the cost associated with parametrization. They have been successfully used in impedance cardiography, wing-design optimization, robotic learning, computational biomechanics, and have more recently been extended to human-in-the-loop systems, such as aerospace and transportation. They include both model-based methods, where a generative model is available or can be learned, in addition to model-free methods, that include regression-based approaches, such as stacked-regression. A more general class of regression-based multi-fidelity methods are Bayesian approaches, e.g. Bayesian linear regression, Gaussian mixture models, Gaussian processes, auto-regressive Gaussian processes, or Bayesian polynomial chaos expansions.
The approach used depends on the domain and properties of the data available, and is similar to the concept of metasynthesis, proposed by Judea Pearl.
Data fidelity spectrum
The fidelity of data can vary along a spectrum between low- and high-fidelity. The next sections provide examples of data across the fidelity spectrum, while defining the benefits and limitations of each type of data.
Low fidelity data (LoFi)
Low-fidelity data (LoFi) includes any data that was produced by a person or Stochastic Process that deviates from the real-world system of interest. For example, LoFi data can be produced by models of a physical system that use approximations to simulate the system, rather than modeling the system in an exhaustive manner.
Moreover, in human-in-the-loop (HITL) situations the goal may be to predict the impact of technology on expert behavior within the real-world operational context. Machine learning can be used to train statistical models that predict expert behavior, provided that an adequate amount of high-fidelity (i.e., real-world) data are available or can be produced.
LoFi benefits |
https://en.wikipedia.org/wiki/Bulletin%20of%20the%20Russian%20Academy%20of%20Sciences%3A%20Physics | Bulletin of the Russian Academy of Sciences: Physics is a translation of the Russian peer-reviewed scientific journal Известия РАН. Серия физическая (Izvestiya Rossiiskoi Akademii Nauk, Seriya Fizicheskaya) that was established in 1936 as the Bulletin of the Academy of Sciences of USSR: Physics Series, obtaining its current title in 1992. The journal publishes exclusively the transactions of various Russian Academy of Sciences events in the field of physics in its widest sense. Previous editors-in-chief included Sergey Ivanovich Vavilov, Abram Ioffe, A.A. Lebedev, B.S. Djelepov, A.V. Gaponov-Grekhov, and F.V. Bunkin. The current editor-in-chief is Dmitry R. Khokhlov (Lomonosov Moscow State University). Originally the journal was translated into French, switching to English in 1974. Until 2008 it was published by Allerton Press and since then by Pleiades Publishing in collaboration with Springer Science+Business Media.
Abstracting and indexing
The journal is abstracted and indexed in:
Astrophysics Data System
Chemical Abstracts Service
EBSCO databases
Ei Compendex
Inspec
ProQuest databases
Scopus
Zentralblatt Math |
https://en.wikipedia.org/wiki/Isoetales | Isoetales, sometimes also written Isoëtales, is an order of plants in the class Lycopodiopsida.
There are about 140-150 living species, all of which are classified in the genus Isoetes (quillworts), with a cosmopolitan distribution, but often scarce to rare. Living species are mostly aquatic or semi-aquatic, and are found in clear ponds and slowly moving streams. Each leaf is slender and broadens downward to a swollen base up to 5 mm wide where the leaves attach in clusters to a bulb-like, underground corm characteristic of most quillworts. This swollen base also contains male and female sporangia, protected by a thin, transparent covering (velum), which is used diagnostically to help identify quillwort species. Quillwort species are very difficult to distinguish by general appearance. The best way to identify them is by examining the megaspores under a microscope.
Isoetes are the only living pteridophytes capable of secondary growth.
Fossils
Some authors include the tree-like "aboresecent lycophytes", which formed forests during the Carboniferous period, and often assigned to their own order, Lepidodendrales, within Isoetales.
Fossilised specimens of Isoetes beestonii have been found in rocks dating to the latest Permian-earliest Triassic. During the Early Triassic, Isoetales, such as the long-stemmed Pleuromeia were dominant over large areas of the globe. The oldest fossil closely resembling modern quillworts is Isoetites rolandii from the Late Jurassic of North America. |
https://en.wikipedia.org/wiki/Spin%20stiffness | The spin stiffness or spin rigidity or helicity modulus or the "superfluid density" (for bosons the superfluid density is proportional to the spin stiffness) is a constant which represents the change in the ground state energy of a spin system as a result of introducing a slow in plane twist of the spins. The importance of this constant is in its use as an indicator of quantum phase transitions—specifically in models with metal-insulator transitions such as Mott insulators. It is also related to other topological invariants such as the Berry phase and Chern numbers as in the Quantum Hall effect.
Mathematically
Mathematically it can be defined by the following equation:
where is the ground state energy, is the twisting angle, and N is the number of lattice sites.
Spin stiffness of the Heisenberg model
Start off with the simple Heisenberg spin Hamiltonian:
Now we introduce a rotation in the system at site i by an angle θi around the z-axis:
Plugging these back into the Heisenberg Hamiltonian:
now let θij = θi - θj and expand around θij = 0 via a MacLaurin expansion only keeping terms up to second order in θij
where the first term is independent of θ and the second term is a perturbation for small θ.
is the z-component of the spin current operator
is the "spin kinetic energy"
Consider now the case of identical twists, θx only that exist along nearest neighbor bonds along the x-axis.
Then since the spin stiffness is related to the difference in the ground state energy by
then for small θx and with the help of second order perturbation theory we get:
See also
Spin wave |
https://en.wikipedia.org/wiki/Nikolai%20Kasterin | Nikolai Petrovich Kasterin (1869–1947) was a physicist and a student of Aleksandr Stoletov. His 1903 doctoral dissertation, portions of which were published in German in the Proceedings of the Royal Academy of Sciences in Amsterdam under the sponsorship of Heike Kamerlingh Onnes, is considered to be a pivotal contribution to multiple scattering theory (MST) by such experts as Paul Peter Ewald and Jan Korringa. The MST formalism is widely used for electronic structure calculations as well as diffraction theory, and is the subject of many books. He lived in the Russian Empire and later the Soviet Union.
Biography
Kasterin studied at the Physical-Mathematical Faculty of Moscow University under the supervision of Aleksandr Stoletov. He graduated in 1892 and continued to work for Stoletov as a laboratory assistant. In 1896-1899, he trained abroad. In 1899, Kasterin returned to Moscow University where he became an assistant professor and taught theoretical physics. In 1905, Kasterin defended his doctoral dissertation "On the propagation of waves in non-uniform medium".
In 1906, Kasterin became a professor at the Department of Physics of Novorossiyskii University in Odessa. He also headed the Institute of Physics. From 1906 to 1922, he was the Chairman of the Department of Physics at Novorossiyskii University.
In 1922, Kasterin moved to the Biophysics Institute in Moscow.
Since 1930, he was a consultant for various scientific institutions including CAGI, Angarsrtoy and the National Institute of Building Materials.
Kasterin authored more than forty scientific publications in theoretical physics. He was also known for his works opposing special relativity. |
https://en.wikipedia.org/wiki/Link%20encryption | Link encryption is an approach to communications security that encrypts and decrypts all network traffic at each network routing point (e.g. network switch, or node through which it passes) until arrival at its final destination. This repeated decryption and encryption is necessary to allow the routing information contained in each transmission to be read and employed further to direct the transmission toward its destination, before which it is re-encrypted. This contrasts with end-to-end encryption where internal information, but not the header/routing information, is encrypted by the sender at the point of origin and only decrypted by the intended recipient.
Link encryption offers two main advantages:
encryption is automatic so there is less opportunity for human error.
if the communications link operates continuously and carries an unvarying level of traffic, link encryption defeats traffic analysis.
On the other hand, end-to-end encryption ensures only the intended recipient has access to the plaintext.
Link encryption can be used with end-to-end systems by superencrypting the messages.
Bulk encryption refers to encrypting a large number of circuits at once, after they have been multiplexed. |
https://en.wikipedia.org/wiki/Ieke%20Moerdijk | Izak (Ieke) Moerdijk (; born 23 January 1958) is a Dutch mathematician, currently working at Utrecht University, who in 2012 won the Spinoza prize.
Education and career
Moerdijk studied mathematics, philosophy and general linguistics at the University of Amsterdam. He obtained his PhD cum laude in 1985 at the same institution. His thesis was entitled Topics in intuitionism and topos theory and was written under the supervision of Anne Sjerp Troelstra.
After that, he worked as postdoctoral researcher at the University of Chicago and Cambridge. From 1988 to 2011 he was professor at Utrecht University. After working at the Mathematical Institute of the Radboud University Nijmegen for a few years, he returned to Utrecht University in 2016.
In 2000 Moerdijk was an invited speaker to the 3rd European Congress of Mathematics. He was elected member of the Royal Netherlands Academy of Arts and Sciences in 2006 and of the Academia Europaea in 2014.
Moerdijk received the 2011 Descartes-Huygens prize for his contribution to French–Dutch scientific collaborations from the Académie des Sciences in Paris. In 2012 he received the Spinoza prize from the Netherlands Organisation for Scientific Research.
Research
Moerdijk's research interests lie in the fields of category theory, algebraic and differential topology, and their applications to mathematical logic.
Moerdijk is seen, together with André Joyal, as one of the founders of algebraic set theory. In 1992 he wrote, together with Saunders Mac Lane, a book on topos theory that became the standard reference on the subject: Sheaves in geometry and logic. A first introduction to topos theory. In 1995 he made pioneering contributions to constructive non-standard analysis, of which he is one of the founders.
Moerdijk's research has also covered topics in differential geometry; in particular, he wrote in 2003 an influential monograph on foliations and Lie groupoids. Recently Moerdijk pursues, among other topics, research on the |
https://en.wikipedia.org/wiki/International%20Society%20for%20Stereology%20%26%20Image%20Analysis | The International Society for Stereology & Image Analysis (ISSIA) is an international scientific society whose purpose is to encourage the development and dissemination of knowledge in stereology and image analysis in a wide range of disciplines. It was founded in 1961. Although the Society is currently based in the Czech Republic, it is an international organization. The former name (until 2017) was International Society for Stereology.
The society both shares the Journal of Microscopy with the Royal Microscopical Society as its official journal as well as having its own journal called Image Analysis & Stereology (formerly known as Acta Stereologica).
Organization
The society is active in all fields of stereology, which is an interdisciplinary field of research concerned with the threedimensional interpretation of lower dimensional samples of materials or tissues. It utilizes random, systematic sampling to provide unbiased and quantitative data from microscopic images. The society is associated with the international journal Image Analysis & Stereology.
Events
Professor Hans Elias organized the first meeting on stereology in 1961 in the Feldberg, the Black Forest of Germany. The aim was to discuss quantification of 3-D objects based on their 2-D sections. The following year the International Society for Stereology (ISS, now ISSIA) convened for its first congress in Vienna, Austria.
The second congress was in Chicago in April 1967, and the third congress was in Bern in 1971. Proceedings of the fourth congress in Gaithersburg 1975 are available on-line. |
https://en.wikipedia.org/wiki/Champion%20Boxing | is a 1984 boxing sports video game developed and published by Sega for the SG-1000, and later ported to the arcades, only in Japan and Europe. It was Sega-AM2 founder and leader Yu Suzuki's debut creation, as well as that of Rieko Kodama. In 1985, a successor of Champion Boxing titled Champion Pro Wrestling was released in the arcades, and ported to the SG-1000 and the MSX home computer the same year. However, this is a professional wrestling game instead of a boxing game.
Development
Yu Suzuki described Champion Boxing as a minor project with very little staff, and said that because of this it allowed him to learn the process of games development with very little pressure. Because the game was understaffed for designers, Suzuki actually contributed some of the drawings for the various punching animations.
According to Suzuki, the game was developed for the SG-1000 first, and then the arcade version was created by simply installing an SG-1000 in an arcade cabinet.
Pengo makes a cameo after a KO. |
https://en.wikipedia.org/wiki/Biased%20positional%20game | A biased positional game is a variant of a positional game. Like most positional games, it is described by a set of positions/points/elements () and a family of subsets (), which are usually called the winning-sets. It is played by two players who take turns picking elements until all elements are taken. While in the standard game each player picks one element per turn, in the biased game each player takes a different number of elements.
More formally, for every two positive integers p and q, a (p:q)-positional game is a game in which the first player picks p elements per turn and the second player picks q elements per turn.
The main question of interest regarding biased positional games is what is their threshold bias - what is the bias in which the winning-power switches from one player to the other player.
Example
As an example, consider the triangle game. In this game, the elements are all edges of a complete graph on n vertices, and the winning-sets are all triangles (=cliques on 3 vertices). Suppose we play it as a Maker-Breaker game, i.e., the goal of Maker (the first player) is to take a triangle and the goal of Breaker (the second player) is to prevent Maker from taking a triangle. Using a simple case-analysis, it can be proved that Maker has a winning strategy whenever n is at least 6. Therefore, it is interesting to ask whether this advantaged can be biased by letting Breaker pick more than 1 element per turn.
Indeed, it is possible to prove that:
For every , Maker wins the (1:q) triangle game on n vertices.
For every , Breaker wins the (1:q) triangle game on n vertices.
A winning condition for Breaker
In an unbiased Maker-Breaker game, the Erdos-Selfridge theorem gives a winning condition for Breaker. This condition can be generalized to biased games as follows:
If , then Breaker has a winning-strategy in the (p:q) game when playing first.
If , then Breaker has a winning-strategy in the (p:q) game even when playing second.
The strategy u |
https://en.wikipedia.org/wiki/Blue%20flower | A blue flower () was a central symbol of inspiration for the Romanticism movement, and remains an enduring motif in Western art today. It stands for desire, love, and the metaphysical striving for the infinite and unreachable. It symbolizes hope and the beauty of things.
Early use of the symbol
German author Novalis introduced the symbol into the Romantic movement through his unfinished coming-of-age story, entitled Heinrich von Ofterdingen. After contemplating a meeting with a stranger, the young Heinrich von Ofterdingen dreams about a blue flower which calls to him and absorbs his attention.
Explanation of the symbol
"This blue flower is the watchword and sacred symbol of the [Romantic] school," according to H.H. Boyesen. "It is meant to symbolize the deep and sacred longings of a poet's soul. Romantic poetry invariably deals with longing; not a definite, formulated desire for some obtainable object, but a dim, mysterious aspiration, a trembling unrest, a vague sense of kinship with the infinite, and a consequent dissatisfaction with every form of happiness which the world has to offer." Thomas Carlyle offered this, that the blue flower "being Poetry, the real object, passion and vocation of young Heinrich, which, through manifold adventures, exertions and sufferings, he is to seek and find."
Use of the symbol
Joseph Freiherr von Eichendorff wrote a poem called Die blaue Blume (The blue flower). Adelbert von Chamisso saw the core of Romanticism in the motif, and Goethe searched for the "Urpflanze" or "original plant" in Italy, which in some interpretations could refer to the blue flower. E. T. A. Hoffmann used the Blue Flower as a symbol for the poetry of Novalis and the "holy miracle of nature" in his short tale "Nachricht von den neuesten Schicksalen des Hundes Berganza".
In 1902, Charles Scribner's Sons published The Blue Flower, a collection of short stories by Henry Van Dyke, the first two of which, "The Blue Flower" and "The Source", refer to the blue |
https://en.wikipedia.org/wiki/Passport%20Carrier%20Release | Passport Carrier Release (PCR) is a version of the Passport Switch (now Multiservice Switch) software designed to run in telecommunications carrier environments. It was formerly developed by Nortel. After the sale in 2009 of most Nortel's assets, the passport SW is still used in several products of Alcatel-Lucent, Ericsson and Kapsch.
The passport products are now part of Ericsson's PPX products under IP Networking. The Ericsson PPX products can be found at the following link.
Technologies
Internally, PCR is largely built up of custom applications on top of a VxWorks kernel. A benefit of the software is that it is completely modular and can load components to Passport control processors (CPs) and function processors (FPs) on an as-needed basis. FPs (also known as line cards) each run their own instance of the Operating System, and as such can be rebooted without the need to take the entire switch out of service, for example due to a software failure. As well, as would be expected, entire cards can be replaced while the system is hot, thus minimizing downtime due to hardware failure.
OAM and provisioning
PCR consists of a custom OAM interface that is highly object oriented. This reflects the modular nature of the operating system. The core component when provisioning IP networks is the Virtual Router (however, a Passport switch can act in more than IP environments). Interfaces are provisioned as "application" objects, which are then in turn connected to Protocol Ports on a Virtual Router. It is best to consider the environment in which provisioning occurs to be object oriented, in the sense that the behaviour of the router is defined based on which objects are instantiated and how they are related. Note that there is a change in this paradigm noticeable in recent releases of PCR -- MPLS, for example, now resides on an object called simply a Router with built-in IP features. This provisioning approach is more similar to that of Cisco or Juniper Networks.
Drawback |
https://en.wikipedia.org/wiki/Calcium%20sorbate | Calcium sorbate is the calcium salt of sorbic acid. Calcium sorbate is a polyunsaturated fatty acid salt.
It is a commonly used food preservative; its E number is E203, but it is no longer allowed to be used in the European Union. |
https://en.wikipedia.org/wiki/Andr%C3%A1s%20Frank | András Frank (born 3 June 1949) is a Hungarian mathematician, working in combinatorics, especially in graph theory, and combinatorial optimisation. He is director of the Institute of Mathematics of the Faculty of Sciences of the Eötvös Loránd University, Budapest.
Mathematical work
Using the LLL-algorithm, Frank, and his student, Éva Tardos developed a general method, which could transform some polynomial-time algorithms into strongly polynomial. He solved the problem of finding the minimum number of edges to be added to a given undirected graph so that in the resulting graph the edge-connectivity between any two vertices u and v is at least a predetermined number f(u,v).
Degrees, awards
He received the Candidate of Mathematical Science degree in 1980, advisor: László Lovász, and the Doctor of Mathematical Science degree (1990) from the Hungarian Academy of Sciences. In 1998 he was an Invited Speaker of the International Congress of Mathematicians in Berlin. He was awarded the Tibor Szele Prize of the János Bolyai Mathematical Society in 2002 and the Albert Szent-Györgyi Prize in 2009. In June 2009 the ELTE Mathematical Institute sponsored a workshop in honor of his 60th birthday. |
https://en.wikipedia.org/wiki/Coxeter%20complex | In mathematics, the Coxeter complex, named after H. S. M. Coxeter, is a geometrical structure (a simplicial complex) associated to a Coxeter group. Coxeter complexes are the basic objects that allow the construction of buildings; they form the apartments of a building.
Construction
The canonical linear representation
The first ingredient in the construction of the Coxeter complex associated to a Coxeter system is a certain representation of , called the canonical representation of .
Let be a Coxeter system with Coxeter matrix . The canonical representation is given by a vector space with basis of formal symbols , which is equipped with the symmetric bilinear form . In particular, . The action of on is then given by .
This representation has several foundational properties in the theory of Coxeter groups; for instance, is positive definite if and only if is finite. It is a faithful representation of .
Chambers and the Tits cone
This representation describes as a reflection group, with the caveat that might not be positive definite. It becomes important then to distinguish the representation from its dual . The vectors lie in and have corresponding dual vectors in given by
where the angled brackets indicate the natural pairing between and .
Now acts on and the action is given by
for and any . Then is a reflection in the hyperplane . One has the fundamental chamber ; this has faces the so-called walls, . The other chambers can be obtained from by translation: they are the for .
The Tits cone is . This need not be the whole of . Of major importance is the fact that is convex. The closure of is a fundamental domain for the action of on .
The Coxeter complex
The Coxeter complex of with respect to is
, where is the multiplicative group of positive reals.
Examples
Finite dihedral groups
The dihedral groups (of order 2n) are Coxeter groups, of corresponding type . These have the presentation .
The canonical linear representa |
https://en.wikipedia.org/wiki/Timeline%20of%20condensed%20matter%20physics | This article lists the main historical events in the history of condensed matter physics. This branch of physics focuses on understanding and studying the physical properties and transitions between phases of matter. Condensed matter refers to materials where particles (atoms, molecules, or ions) are closely packed together or under interaction, such as solids and liquids. This field explores a wide range of phenomena, including the electronic, magnetic, thermal, and mechanical properties of matter.
This timeline includes developments in subfields of condensed matter physics such as theoretical crystallography, solid-state physics, soft matter physics, mesoscopic physics, material physics, low-temperature physics, microscopic theories of magnetism in matter and optical properties of matter and metamaterials.
Even if material properties were modeled before 1900, condensed matter topics were considered as part of physics since the development of quantum mechanics and microscopic theories of matter. According to Philip W. Anderson, the term "condensed matter" appeared about 1965.
For history of fluid mechanics, see timeline of fluid and continuum mechanics.
Before quantum mechanics
Prehistory
7000-3300 BC – New Stone Age: humans develop pottery and tools from stone and flint.
3300-1200 BC – Bronze Age: mixing copper and tin, provided the development of development of bronze tools.
1200-300 BC- Iron Age: bronze tools are replaced with iron and steel.
Antiquity
8th century BC: first writings on the magnetic properties of lodestone in Ancient Greece.
6th century BC – Thales of Miletus observes that rubbing fur on various substances, such as amber, would cause an attraction between the two, which is now known to be caused by static electricity.
5th century BC – Leucippus and Democritus postulate the philosophy of atomism.
4th century BC - Aristotle describes the composition of matter in terms of the four classical elements, founding Aristotelian physics.
1 |
https://en.wikipedia.org/wiki/Alar%20plate | The alar plate (or alar lamina) is a neural structure in the embryonic nervous system, part of the dorsal side of the neural tube, that involves the communication of general somatic and general visceral sensory impulses. The caudal part later becomes the sensory axon part of the spinal cord.
The alar plate specifically later on becomes the dorsal gray of the spinal cord, and also develops into the sensory nuclei of cranial nerves V, VII, VIII, IX, and X. The inferior olivary nucleus, mesencephalic nucleus of V, and main sensory nucleus of V are also developed from this plate. The cerebellum also develops from the alar plate, particularly from the rhombic lip. This is considered an exception to the general differentiation scheme from the alar plate, as the alar plate generally gives rise to sensory derivatives.
See also
Basal plate |
https://en.wikipedia.org/wiki/Geopositioning | Geopositioning is the process of determining or estimating the geographic position of an object.
Geopositioning yields a set of geographic coordinates (such as latitude and longitude) in a given map datum; positions may also be expressed as a bearing and range from a known landmark.
In turn, positions can determine a meaningful location, such as a street address.
Specific instances include: animal geotracking, the process of inferring the location of animals over time; positioning system, the mechanisms for the determination of geographic positions in general; internet geolocation, geolocating a device connected to the internet; and mobile phone tracking.
Background
Geopositioning uses various visual and electronic methods including position lines and position circles, celestial navigation, radio navigation, and the use of satellite navigation systems.
The calculation requires measurements or observations of distances or angles to reference points whose positions are known. In 2D surveys, observations of three reference points are enough to compute a position in a two-dimensional plane. In practice, observations are subject to errors resulting from various physical and atmospheric factors that influence the measurement of distances and angles.
A practical example of obtaining a position fix would be for a ship to take bearing measurements on three lighthouses positioned along the coast. These measurements could be made visually using a hand bearing compass, or in poor visibility, electronically using radar or radio direction finding. Since all physical observations are subject to errors, the resulting position fix is also subject to inaccuracy. Although in theory two lines of position (LOP) are enough to define a point, in practice 'crossing' more LOPs provides greater accuracy and confidence, especially if the lines cross at a good angle to each other. Three LOPs are considered the minimum for a practical navigational fix. The three LOPs when drawn on the char |
https://en.wikipedia.org/wiki/Momentum-transfer%20cross%20section | In physics, and especially scattering theory, the momentum-transfer cross section (sometimes known as the momentum-transport cross section) is an effective scattering cross section useful for describing the average momentum transferred from a particle when it collides with a target. Essentially, it contains all the information about a scattering process necessary for calculating average momentum transfers but ignores other details about the scattering angle.
The momentum-transfer cross section is defined in terms of an (azimuthally symmetric and momentum independent) differential cross section by
The momentum-transfer cross section can be written in terms of the phase shifts from a partial wave analysis as
Explanation
The factor of arises as follows. Let the incoming particle be traveling along the -axis with vector momentum
Suppose the particle scatters off the target with polar angle and azimuthal angle plane. Its new momentum is
For collision to much heavier target than striking particle (ex: electron incident on the atom or ion), so
By conservation of momentum, the target has acquired momentum
Now, if many particles scatter off the target, and the target is assumed to have azimuthal symmetry, then the radial ( and ) components of the transferred momentum will average to zero. The average momentum transfer will be just . If we do the full averaging over all possible scattering events, we get
where the total cross section is
Here, the averaging is done by using expected value calculation (see as a probability density function). Therefore, for a given total cross section, one does not need to compute new integrals for every possible momentum in order to determine the average momentum transferred to a target. One just needs to compute .
Application
This concept is used in calculating charge radius of nuclei such as proton and deuteron by electron scattering experiments.
To this purpose a useful quantity called the scattering vector having |
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