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https://en.wikipedia.org/wiki/Reciprocals%20of%20primes | The reciprocals of prime numbers have been of interest to mathematicians for various reasons. They do not have a finite sum, as Leonhard Euler proved in 1737.
Like all rational numbers, the reciprocals of primes have repeating decimal representations. In his later years, George Salmon (1819–1904) concerned himself with the repeating periods of these decimal representations of reciprocals of primes.
Contemporaneously, William Shanks (1812–1882) calculated numerous reciprocals of primes and their repeating periods, and published two papers "On Periods in the Reciprocals of Primes" in 1873 and 1874. In 1874 he also published a table of primes, and the periods of their reciprocals, up to 20,000 (with help from and "communicated by the Rev. George Salmon"), and pointed out the errors in previous tables by three other authors.
Rules for calculating the periods of repeating decimals from rational fractions were given by James Whitbread Lee Glaisher in 1878. For a prime , the period of its reciprocal will be equal to or will divide .
The sequence of recurrence periods of the reciprocal primes appears in the 1973 Handbook of Integer Sequences.
Unique primes
A prime p (where p ≠ 2, 5 when working in base 10) is called unique if there is no other prime q such that the period length of the decimal expansion of its reciprocal, 1 / p, is equal to the period length of the reciprocal of q, 1 / q. For example, 3 is the only prime with period 1, 11 is the only prime with period 2, 37 is the only prime with period 3, 101 is the only prime with period 4, so they are unique primes. Unique primes were described by Samuel Yates in 1980.
At present, more than fifty unique primes or probable primes are known. However, there are only twenty-three unique primes below 10100. contains a list of unique primes and are those primes ordered by period length; contains periods (ordered by corresponding primes) and contains periods, sorted, corresponding with A007615.
the repunit ( |
https://en.wikipedia.org/wiki/Daikon%20%28system%29 | Daikon is a computer program that detects likely invariants of programs. An invariant is a condition that always holds true at certain points in the program. It is mainly used for debugging programs in late development, or checking modifications to existing code.
Properties
Daikon can detect properties in C, C++, Java, Perl, and IOA programs, as well as spreadsheet files or other data sources. Daikon is easy to extend and is free software.
External links
Daikon Official home site
Source Repository on GitHub
Dynamically Discovering Likely Program Invariants, Michael D. Ernst PhD. Thesis (using Daikon) |
https://en.wikipedia.org/wiki/Lightweight%20programming%20language | Lightweight programming languages are designed to have small memory footprint, are easy to implement (important when porting a language to different computer systems), and/or have minimalist syntax and features.
These programming languages have simple syntax and semantics, so one can learn them quickly and easily. Some lightweight languages (for example Lisp, Forth, and Tcl) are so simple to implement that they have many implementations (dialects).
Compiled languages
BASIC
BASIC implementations like Tiny BASIC were designed to be lightweight so that they could run on the microcomputers of the 1980s, because of memory constraints.
Forth
Forth is a stack-based concatenative imperative programming language using reverse polish notation.
Toy languages
Brainfuck
Brainfuck is an extremely minimalist esoteric programming language.
Scripting languages
Io
Io is a prototype-based object-oriented scripting language.
Lisp
Lisp-like languages are very simple to implement, so there are many lightweight implementations of it.
There are some notable implementations:
newLISP
PicoLisp
uLisp
Derivatives of Lisp:
Pico
Rebol
Red
Scheme
Tcl
Tcl-like languages can be easily implemented because of its simple syntax. Tcl itself maybe not so lightweight, but there exists some, if not many, lightweight implementations of languages which have Tcl-like syntax.
Embedded languages
ECMAScript
There are many embeddable implementation of ECMAScript like:
Duktape
Espruino
JerryScript
jsish
MuJS
QuickJS
Derivatives of ECMAScript:
Squirrel
Lua
Lua is a small (C source is approx. 300 kB tarball, as of version 5.3.5), portable and embeddable scripting language (with LuaJIT as a JIT compiler improving speed). It can be embedded in applications such as computer games to provide runtime scripting capabilities.
Wren
Wren is a small, fast, object-oriented scripting language. |
https://en.wikipedia.org/wiki/Glossophyte | The glossophytes are a clade of seed plants comprising the glossopterids and their descendants. This includes the Gnetales and angiosperms, as well as Bennettitales.
Their monophyly is rather well supported by molecular methods, although their internal relationships are somewhat more shaky.
The clade had diverged by the Permian, when glossopterids appear in the fossil record. |
https://en.wikipedia.org/wiki/Dynamic%20substructuring | Dynamic Substructuring (DS) is an engineering tool used to model and analyse the dynamics of mechanical systems by means of its components or substructures. Using the dynamic substructuring approach one is able to analyse the dynamic behaviour of substructures separately and to later on calculate the assembled dynamics using coupling procedures. Dynamic substructuring has several advantages over the analysis of the fully assembled system:
Substructures can be modelled in the domain that is most appropriate, e.g. experimentally obtained substructures can be combined with numerical models.
Large and/or complex systems can be optimized on substructure level.
Numerical computation load can be reduced as solving several substructures is computationally less demanding than solving one large system.
Substructure models of different development groups can be shared and combined without exposing the modelling details.
Dynamic substructuring is particularly tailored to simulation of mechanical vibrations, which has implications for many product aspects such as sound / acoustics, fatigue / durability, comfort and safety. Also, dynamic substructuring is applicable to any scale of size and frequency. It is therefore a widely used paradigm in industrial applications ranging from automotive and aerospace engineering to design of wind turbines and high-tech precision machinery.
History
The roots of dynamic substructuring can be found in the field of domain decomposition. In 1890 the mathematician Hermann Schwarz came up with an iterative procedure for domain decomposition which allows to solve for continuous coupled subdomains. However, many of the analytical models of coupled continuous subdomains do not have closed-form solutions, which led to discretization and approximation techniques such as the Ritz method (which is sometimes called the Rayleigh-Ritz method due to the similarity between Ritz's formulation and the Rayleigh ratio) the boundary element method (BEM) and t |
https://en.wikipedia.org/wiki/The%20Fertility%20Transition%20in%20Iran | The Fertility Transition in Iran: Revolution and Reproduction is a 2009 book by Meimanat Hosseini-Chavoshi, Peter McDonald and Mohammad Jalal Abbasi-Shavazi in which the authors examine the fertility rate changes in the Islamic Republic of Iran.
The book was awarded Iran's Book of the Year Award. |
https://en.wikipedia.org/wiki/Multipath%20propagation | In radio communication, multipath is the propagation phenomenon that results in radio signals reaching the receiving antenna by two or more paths. Causes of multipath include atmospheric ducting, ionospheric reflection and refraction, and reflection from water bodies and terrestrial objects such as mountains and buildings. When the same signal is received over more than one path, it can create interference and phase shifting of the signal. Destructive interference causes fading; this may cause a radio signal to become too weak in certain areas to be received adequately. For this reason, this effect is also known as multipath interference or multipath distortion.
Where the magnitudes of the signals arriving by the various paths have a distribution known as the Rayleigh distribution, this is known as Rayleigh fading. Where one component (often, but not necessarily, a line of sight component) dominates, a Rician distribution provides a more accurate model, and this is known as Rician fading. Where two components dominate, the behavior is best modeled with the two-wave with diffuse power (TWDP) distribution. All of these descriptions are commonly used and accepted and lead to results. However, they are generic and abstract/hide/approximate the underlying physics.
Interference
Multipath interference is a phenomenon in the physics of waves whereby a wave from a source travels to a detector via two or more paths and the two (or more) components of the wave interfere constructively or destructively. Multipath interference is a common cause of "ghosting" in analog television broadcasts and of fading of radio waves.
The condition necessary is that the components of the wave remain coherent throughout the whole extent of their travel.
The interference will arise owing to the two (or more) components of the wave having, in general, travelled a different length (as measured by optical path length – geometric length and refraction (differing optical speed)), and thus arrivin |
https://en.wikipedia.org/wiki/Dharmendra%20Modha |
Dharmendra S. Modha is an Indian American manager and lead researcher of the Cognitive Computing group at IBM Almaden Research Center. He is known for his pioneering works in Artificial Intelligence and Mind Simulation. In November 2009, Modha announced at a supercomputing conference that his team had written a program that simulated a cat brain. He is the recipient of multiple honors, including the Gordon Bell Prize, given each year to recognize outstanding achievement in high-performance computing applications. In November 2012, Modha announced on his blog that using 96 Blue Gene/Q racks of the Lawrence Livermore National Laboratory Sequoia supercomputer (1,572,864 processor cores, 1.5 PB memory, 98,304 MPI processes, and 6,291,456 threads), a combined IBM and LBNL team achieved an unprecedented scale of 2.084 billion neurosynaptic cores containing 530 billion neurons and 137 trillion synapses running only 1542× slower than real time. In August 2014 a paper describing the TrueNorth Architecture, "the first-ever production-scale 'neuromorphic' computer chip designed to work more like a mammalian brain than" a processor was published in the journal Science. TrueNorth project culminated in a 64 million neuron system for running deep neural network applications.
Personal life
Modha holds a BTech in Computer Science and Engineering from IIT Bombay (1990), India and a PhD in Electrical and Computer Engineering from UCSD. He received his PhD at the Jacobs School of Engineering in 1995 and is now manager of Cognitive Computing at IBM's Almaden Research Center and a Master Inventor. He is a Senior Member of IEEE and a member of AAAS, ACM, and SfN.
Achievements
Modha is manager of the Cognitive Computing group at IBM's Almaden Research Center. He chaired IBM's 2006 Almaden Institute on Cognitive Computing, co-chaired Cognitive Computing 2007 at Berkeley, CA, and was a speaker at the Decade of the Mind Symposium in May 2007. He is the Principal Investigator for DARPA SyN |
https://en.wikipedia.org/wiki/Moisture%20stress | Moisture stress is a form of abiotic stress that occurs when the moisture of plant tissues is reduced to suboptimal levels. Water stress occurs in response to atmospheric and soil water availability when the transpiration rate exceeds the rate of water uptake by the roots and cells lose turgor pressure. Moisture stress is described by two main metrics, water potential and water content.
Moisture stress has an effect on stomatal opening, mainly causing a closure in stomata as to reduce the amount of carbon dioxide assimilation. Closing of the stomata also slows the rate of transpiration, which limits water loss and helps to prevent the wilting effects of moisture stress. This closing can be trigged by the roots sensing dry soil and in response producing the hormone ABA which when transported up the xylem into the leaves will reduce stomatal conductance and wall extensibility of growing cells. This lowers the rates of transpiration, photosynthesis and leaf expansion. ABA also increases the loosening of growing root cell walls and in turn increases root growth in an effort to find water in the soil.
Phenotypic response of plants to long-term water stress was measured in corn and showed that plants respond to water stress with both an increase in root growth both laterally and vertically. In all Droughted conditions the corn showed decrease in plant height and yield due to the decrease in water availability.
Genes induced during water-stress conditions are thought to function not only in protecting cells from water deficit by the production of important metabolic proteins but also in the regulation of genes for signal transduction in the water-stress response. There are four pathways that have been described that show the plants genetic response to moisture stress; two are ABA dependent while two are ABA independent. They all affect gene expression that increases the plants water stress tolerance.
The effects of moisture stress on photosynthesis can depend as much |
https://en.wikipedia.org/wiki/RingCube%20vDesk | RingCube vDesk is a Desktop virtualization product from RingCube Technologies. vDesk is a client virtualization or virtual workspace platform which virtualizes the entire desktop at an operating system level. The platform can be deployed in four different modes: on a local PC, on an external USB device, streamed across a network, or in conjunction with existing VDI solutions.
See also
Desktop virtualization
MojoPac - Similar product also by RingCube Technologies
Portable application creators
Windows To Go |
https://en.wikipedia.org/wiki/Zak%20transform | In mathematics, the Zak transform (also known as the Gelfand mapping) is a certain operation which takes as input a function of one variable and produces as output a function of two variables. The output function is called the Zak transform of the input function. The transform is defined as an infinite series in which each term is a product of a dilation of a translation by an integer of the function and an exponential function. In applications of Zak transform to signal processing the input function represents a signal and the transform will be a mixed time–frequency representation of the signal. The signal may be real valued or complex-valued, defined on a continuous set (for example, the real numbers) or a discrete set (for example, the integers or a finite subset of integers). The Zak transform is a generalization of the discrete Fourier transform.
The Zak transform had been discovered by several people in different fields and was called by different names. It was called the "Gelfand mapping" because Israel Gelfand introduced it in his work on eigenfunction expansions. The transform was rediscovered independently by Joshua Zak in 1967 who called it the "k-q representation". There seems to be a general consensus among experts in the field to call it the Zak transform, since Zak was the first to systematically study that transform in a more general setting and recognize its usefulness.
Continuous-time Zak transform: Definition
In defining the continuous-time Zak transform, the input function is a function of a real variable. So, let f(t) be a function of a real variable t. The continuous-time Zak transform of f(t) is a function of two real variables one of which is t. The other variable may be denoted by w. The continuous-time Zak transform has been defined variously.
Definition 1
Let a be a positive constant. The Zak transform of f(t), denoted by Za[f], is a function of t and w defined by
.
Definition 2
The special case of Definition 1 obtained by taking |
https://en.wikipedia.org/wiki/Behaviorally%20anchored%20rating%20scales | Behaviorally anchored rating scales (BARS) are scales used to rate performance. BARS are normally presented vertically with scale points ranging from five to nine. It is an appraisal method that aims to combine the benefits of narratives, critical incidents, and quantified ratings by anchoring a quantified scale with specific narrative examples of good, moderate, and poor performance.
Background
BARS were developed in response to dissatisfaction with the subjectivity involved in using traditional rating scales such as the graphic rating scale. A review of BARS concluded that the strength of this rating format may lie primarily in the performance dimensions which are gathered rather than the distinction between behavioral and numerical scale anchors.
Benefits of BARS
BARS are rating scales that add behavioral scale anchors to traditional rating scales (e.g., graphic rating scales). In comparison to other rating scales, BARS are intended to facilitate more accurate ratings of the target person's behavior or performance. However, whereas the BARS is often regarded as a superior performance appraisal method, BARS may still suffer from unreliability, leniency bias and lack of discriminant validity between performance dimensions.
Developing BARS
BARS are developed using data collected through the critical incident technique, or through the use of comprehensive data about the tasks performed by a job incumbent, such as might be collected through a task analysis. In order to construct BARS, several basic steps, outlined below, are followed.
Examples of effective and ineffective behavior related to job are collected from people with knowledge of job using the critical incident technique. Alternatively, data may be collected through the careful examination of data from a recent task analysis.
These data are then converted into performance dimensions. To convert these data into performance dimensions, examples of behavior (such as critical incidents) are sorted into homog |
https://en.wikipedia.org/wiki/Comparison%20of%20file%20transfer%20protocols | This article lists communication protocols that are designed for file transfer over a telecommunications network.
Protocols for shared file systems—such as 9P and the Network File System—are beyond the scope of this article, as are file synchronization protocols.
Protocols for packet-switched networks
A packet-switched network transmits data that is divided into units called packets. A packet comprises a header (which describes the packet) and a payload (the data). The Internet is a packet-switched network, and most of the protocols in this list are designed for its protocol stack, the IP protocol suite.
They use one of two transport layer protocols: the Transmission Control Protocol (TCP) or the User Datagram Protocol (UDP). In the tables below, the "Transport" column indicates which protocol(s) the transfer protocol uses at the transport layer. Some protocols designed to transmit data over UDP also use a TCP port for oversight.
The "Server port" column indicates the port from which the server transmits data. In the case of FTP, this port differs from the listening port. Some protocols—including FTP, FTP Secure, FASP, and Tsunami—listen on a "control port" or "command port", at which they receive commands from the client.
Similarly, the encryption scheme indicated in the "Encryption" column applies to transmitted data only, and not to the authentication system.
Overview
Features
The "Managed" column indicates whether the protocol is designed for managed file transfer (MFT). MFT protocols prioritise secure transmission in industrial applications that require such features as auditable transaction records, monitoring, and end-to-end data security. Such protocols may be preferred for electronic data interchange.
Ports
In the table below, the data port is the network port or range of ports through which the protocol transmits file data. The control port is the port used for the dialogue of commands and status updates between client and server.
The column "Assi |
https://en.wikipedia.org/wiki/Audio%20watermark | An audio watermark is a unique electronic identifier embedded in an audio signal, typically used to identify ownership of copyright. It is similar to a watermark on a photograph.
Digital watermarking is the process of embedding information into a signal (e.g. audio, video or pictures) in a way that is difficult to remove. If the signal is copied, then the information is also carried in the copy. Watermarking has become increasingly important to enable copyright protection and ownership verification.
Spread spectrum
One technique for audio watermarking is spread spectrum audio watermarking (SSW). In SSW, a narrow-band signal is transmitted over a much larger bandwidth such that the signal energy presented in any signal frequency is undetectable. Thus the watermark is spread over many frequency bands so that the energy in one band is undetectable. An interesting feature of this watermarking technique is that destroying it requires noise of high amplitude to be added to all frequency bands.
Spreading spectrum is done by a pseudonoise (PN) sequence. In conventional SSW approaches, the receiver must know the PN sequence used at the transmitter as well as the location of the watermark in the watermarked signal for detecting hidden information.
Although PN sequence detection is possible by using heuristic approaches such as evolutionary algorithms, the high computational cost of this task can make it impractical. Much of the computational complexity involved in the use of evolutionary algorithms as an optimization tool is due to the fitness function evaluation that may either be very difficult to define or be computationally very expensive.
One of the recent proposed approaches—in fast recovering the PN sequence- is the use of fitness granulation as a promising "fitness approximation" scheme. With the use of the fitness granulation approach called "Adaptive Fuzzy Fitness Granulation (AFFG)", the expensive fitness evaluation step is replaced by an approximate model. |
https://en.wikipedia.org/wiki/Rhizostomins | Rhizostomins are proteins that are part of a pigment family only found in jellyfish in the order Rhizostomeae. These proteins are composed of a Kringle domain inserted within a cysteine-rich Frizzled domain, first identified in 2004 as the blue pigment in the barrel jellyfish Rhizostoma pulmo. It also appears in rhizostome jellyfish that do not appear blue, such as in Nemopilema nomurai, which typically presents red-brown coloration. It has been hypothesized that pigments in this family act as a sunscreen, protecting from harmful ultraviolet radiation. Natural blue pigments, such as some of the rhizostomins, are rare and there is a growing need for industrial purposes. |
https://en.wikipedia.org/wiki/Iwasawa%20manifold | In mathematics, in the field of differential geometry, an Iwasawa manifold is a compact quotient of a 3-dimensional complex Heisenberg group by a cocompact, discrete subgroup. An
Iwasawa manifold is a nilmanifold, of real dimension 6.
Iwasawa manifolds give examples where the first two terms E1 and E2 of the Frölicher spectral sequence are not isomorphic.
As a complex manifold, such an Iwasawa manifold is an important example of
a compact complex manifold which does not admit any Kähler metric. |
https://en.wikipedia.org/wiki/Huff%20paste | Huff paste is a cooking technique involving making a stiff pie shell (or coffyn) using a mixture of flour, suet, and boiling water. The pastry when cooked creates a tough protective layer around the food inside. When cooked, the pastry is generally discarded as it is virtually inedible. However, the shell becomes soaked with the meat juices and historically was sometimes eaten by house servants after the meal had concluded.
Huff paste's main purpose is simply to create a solid container for the pie's ingredients. The flour itself is stronger than normal flour, often made from coarsely ground rye, and suet, which is mixed with hot water to create what was an early form of hot water crust pastry.
Huff paste can be moulded into a variety of shapes, called coffyns or coffers, similar to a Cornish pasty. A benefit of these early pies was that meat could be preserved for several months and the food contained within was protected from contamination. It also allowed food to be preserved so that country dwellers could send it over long distances as gifts to their friends in other towns or areas.
Shells of huff paste can also be baked empty, or "blind". After baking, the pastry is brushed with egg yolk to give it a golden color, and later filled with a mixture of meat and spices and then baked.
A dish from Wiltshire, called the Devizes Pie, is layered forcemeat or offal cooked under a huff paste.
See also
Beef Wellington
List of pastries |
https://en.wikipedia.org/wiki/Logic%20alphabet | The logic alphabet, also called the X-stem Logic Alphabet (XLA), constitutes an iconic set of symbols that systematically represents the sixteen possible binary truth functions of logic. The logic alphabet was developed by Shea Zellweger. The major emphasis of his iconic "logic alphabet" is to provide a more cognitively ergonomic notation for logic. Zellweger's visually iconic system more readily reveals, to the novice and expert alike, the underlying symmetry relationships and geometric properties of the sixteen binary connectives within Boolean algebra.
Truth functions
Truth functions are functions from sequences of truth values to truth values. A unary truth function, for example, takes a single truth value and maps it to another truth value. Similarly, a binary truth function maps ordered pairs of truth values to truth values, while a ternary truth function maps ordered triples of truth values to truth values, and so on.
In the unary case, there are two possible inputs, viz. T and F, and thus four possible unary truth functions: one mapping T to T and F to F, one mapping T to F and F to F, one mapping T to T and F to T, and finally one mapping T to F and F to T, this last one corresponding to the familiar operation of logical negation. In the form of a table, the four unary truth functions may be represented as follows.
In the binary case, there are four possible inputs, viz. (T, T), (T, F), (F, T), and (F, F), thus yielding sixteen possible binary truth functions – in general, there are n-ary truth functions for each natural number n. The sixteen possible binary truth functions are listed in the table below.
Content
Zellweger's logic alphabet offers a visually systematic way of representing each of the sixteen binary truth functions. The idea behind the logic alphabet is to first represent the sixteen binary truth functions in the form of a square matrix rather than the more familiar tabular format seen in the table above, and then to assign a letter shape |
https://en.wikipedia.org/wiki/Switch56 | Nortel's Switch56 was a networking protocol built on top of the telephone cabling hardware of their Digital Multiplex System and other telephone switches.
The name comes from the fact that Switch56 carried 56 kbit/s of data on its 64 kbit/s lines, as opposed to most systems, including ISDN, where the entire 64 kbit/s bandwidth was available for data. The speed was a side effect of Nortel using a 2-wire cable to carry both voice and switching commands, as opposed to other systems where the command data was carried on a separate set of low-speed lines. Switch56 "folded" the two sources of data into one, placing a single bit from the command channel onto the end of every 7 bits of data, similar to the original T-carrier supervision scheme. This data was split out at the "far end" as 56 kbit/s and 8 kbit/s subchannels.
Switch56 was built on top of the basic Nortel hardware to allow computers to put data into the existing telephony network. Although slow compared to even contemporary systems, Switch56 allowed network traffic to flow not only within an office like other LAN systems, but between any branch offices that were connected using a Nortel PBX like the Meridian Norstar. This was a much easier option to install than ISDN for most offices, requiring nothing more than a Switch56 bridge to their existing network. For the LAN role new telephone terminals were produced with a RS-232C port on the back, which were then plugged into the user's computer and used with custom software. Although interesting in theory, it appears Switch56 saw little use in this role.
Network protocols
Telephone exchange equipment |
https://en.wikipedia.org/wiki/Internet%20Mapping%20Project | The Internet Mapping Project
was started by William Cheswick and Hal Burch at Bell Labs in 1997. It has collected and preserved traceroute-style paths to some hundreds of thousands of networks almost daily since 1998. The project included visualization of the Internet data, and the Internet maps were widely disseminated.
The technology is now used by Lumeta, a spinoff of Bell Labs, to map corporate and government networks.
Although Cheswick left Lumeta in September 2006, Lumeta continues to map both the IPv4 and IPv6 Internet. The data allows for both a snapshot and view over time of the routed infrastructure of a particular geographical area, company, organization, etc.
Cheswick continues to collect and preserve the data, and it is available for research purposes. According to Cheswick, a main goal of the project was to collect the data over time, and make a time-lapse movie of the growth of the Internet.
Techniques
The techniques available for network discovery rely on hop-limited probes of the type used by the Unix traceroute utility or the Windows NT tracert.exe tool. A Traceroute-style network probe follows the path that network packets take from a source node to a destination node. This technique uses Internet Protocol packets with an 8-bit time to live (TTL) header field. As a packet passes through routers on the Internet, each router decreases the TTL value by one until it reaches zero. When a router receives a packet with a TTL value of zero, it drops the packet instead of forwarding it. At this point, it sends an Internet Control Message Protocol (ICMP) error message to the source node where the packet originated indicating that the packet exceeded its maximum transit time.
Active Probing – Active probing is a series of probes set out through a network to obtain data. Active probing is used in internet mapping to discover the topology of the Internet. Topology maps of the Internet are an important tool for characterizing the infrastructure and und |
https://en.wikipedia.org/wiki/Medial%20plantar%20artery | The medial plantar artery (internal plantar artery), much smaller than the lateral plantar artery, passes forward along the medial side of the foot.
It is at first situated above the abductor hallucis, and then between it and the flexor digitorum brevis, both of which it supplies.
At the base of the first metatarsal bone, where it is much diminished in size, it passes along the medial border of the first toe, anastomosing with the first dorsal metatarsal artery.
Small superficial digital branches accompany the digital branches of the medial plantar nerve and join the plantar metatarsal arteries of the first three spaces.
Branches
A superficial branch which supplies a plantar digital artery to the medial side of the 1st toe, and a deep branch which assists in supplying blood to the plantar metatarsal arteries.
Additional images |
https://en.wikipedia.org/wiki/Bacterial%20oxidation | Bacteria biooxidation is an oxidation process caused by microbes where the valuable metal remains (but becomes enriched) in the solid phase. In this process, the metal remains in the solid phase and the liquid can be discarded.
Bacterial oxidation is a biohydrometallurgical process developed for pre-cyanidation treatment of refractory gold ores or concentrates. The bacterial culture is a mixed culture of Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans. The bacterial oxidation process comprises contacting refractory sulfide ROM ore or concentrate with a strain of the bacterial culture for a suitable treatment period under an optimum operating environment. The bacteria oxidise the sulfide minerals, thus liberating the occluded gold for subsequent recovery via cyanidation.
The BIOX® process is a proprietary technology owned by Biomin South Africa and used under licence by a number of operating mines. The BIOX® process involves bacterial oxidation in agitated tanks for pre-treatment of refractory ores and concentrates ahead of conventional cyanide leach for gold recovery.
Under controlled continuous plant conditions, the number of bacterial cells and their activity is optimised to attain the highest rate of sulfide oxidation. The bacteria require a very acidic environment (pH 1.0 to 4.0), a temperature of between 30 and 45 °C, and a steady supply of oxygen and carbon dioxide for optimum growth and activity. The unusual operating conditions for the bacteria are not favourable for the growth of most other microbes, thus eliminating the need for sterility during the bacterial oxidation process. Because organic substances are toxic to the bacteria, they are non-pathogenic and incapable of causing disease. The bacteria employed in the process do not, therefore, pose a health risk to humans or any animals.
The bacterial oxidation of iron sulfide minerals produces iron(III) sulfate and sulfuric acid, and in the case of |
https://en.wikipedia.org/wiki/Endoplasmic-reticulum-associated%20protein%20degradation | Endoplasmic-reticulum-associated protein degradation (ERAD) designates a cellular pathway which targets misfolded proteins of the endoplasmic reticulum for ubiquitination and subsequent degradation by a protein-degrading complex, called the proteasome.
Mechanism
The process of ERAD can be divided into three steps:
Recognition of misfolded or mutated proteins in the endoplasmic reticulum
The recognition of misfolded or mutated proteins depends on the detection of substructures within proteins such as exposed hydrophobic regions, unpaired cysteine residues and immature glycans.
In mammalian cells for example, there exists a mechanism called glycan processing. In this mechanism, the lectin-type chaperones calnexin/calreticulin (CNX/CRT) provide immature glycoproteins the opportunity to reach their native conformation. They can do this by way of reglucosylating these glycoproteins by an enzyme called UDP-glucose-glycoprotein glucosyltransferase also known as UGGT. Terminally misfolded proteins, however, must be extracted from CNX/CRT. This is carried out by members of the EDEM (ER degradation-enhancing α-mannosidase-like protein) family (EDEM1-3) and ER mannosidase I. This mannosidase removes one mannose residue from the glycoprotein and the latter is recognized by EDEM. Eventually EDEM will target the misfolded glycoproteins for degradation by facilitating binding of ERAD lectins OS9 and XTP3-B.
Retro-translocation into the cytosol
Because the ubiquitin–proteasome system (UPS) is located in the cytosol, terminally misfolded proteins have to be transported from the endoplasmic reticulum back into cytoplasm. Most evidence suggest that the Hrd1 E3 ubiquitin-protein ligase can function as a retrotranslocon or dislocon to transport substrates into the cytosol. Hrd1 is not required for all ERAD events, so it is likely that other proteins contribute to this process. For example, glycosylated substrates are recognized by the E3 Fbs2 lectin. Further, this translocati |
https://en.wikipedia.org/wiki/Muisca%20numerals | Muisca numerals were the numeric notation system used by the Muisca, one of the civilizations of the Americas before the Spanish conquest of the Muisca. Just like the Mayas, the Muisca had a vigesimal numerical system, based on multiples of twenty (Chibcha: gueta). The Muisca numerals were based on counting with fingers and toes. They had specific numbers from one to ten, yet for the numbers between eleven and nineteen they used "foot one" (11) to "foot nine" (19). The number 20 was the 'perfect' number for the Muisca which is visible in their calendar. To calculate higher numbers than 20 they used multiples of their 'perfect' number; gue-muyhica would be "20 times 4", so 80. To describe "50" they used "20 times 2 plus 10"; gue-bosa asaqui ubchihica, transcribed from guêboʒhas aſaqɣ hubchìhicâ. In their calendar, which was lunisolar, they only counted from one to ten and twenty. Each number had a special meaning, related to their deities and certain animals, especially the abundant toads.
For the representation of their numbers they used digits inspired by their natural surroundings, especially toads; ata ("one") and aca ("nine") were both derived from the animals so abundant on the Bogotá savanna and other parts of the Altiplano Cundiboyacense where the Muisca lived in their confederation.
The most important scholars who provided knowledge about the Muisca numerals were Bernardo de Lugo (1619), Pedro Simón (17th century), Alexander von Humboldt and José Domingo Duquesne (late 18th and 19th century) and Liborio Zerda.
Numerals
The Muisca used a vigesimal counting system and counted primarily with their fingers and secondarily with their toes. Their system went from 1 to 10 and for higher numerations they used the prefix quihicha or qhicha, which means "foot" in their Chibcha language Muysccubun. Eleven became thus "foot one", twelve: "foot two", etc. As in the other pre-Columbian civilizations, the number 20 was special. It was the total number of all body extre |
https://en.wikipedia.org/wiki/Parallel%20external%20memory | In computer science, a parallel external memory (PEM) model is a cache-aware, external-memory abstract machine. It is the parallel-computing analogy to the single-processor external memory (EM) model. In a similar way, it is the cache-aware analogy to the parallel random-access machine (PRAM). The PEM model consists of a number of processors, together with their respective private caches and a shared main memory.
Model
Definition
The PEM model is a combination of the EM model and the PRAM model. The PEM model is a computation model which consists of processors and a two-level memory hierarchy. This memory hierarchy consists of a large external memory (main memory) of size and small internal memories (caches). The processors share the main memory. Each cache is exclusive to a single processor. A processor can't access another’s cache. The caches have a size which is partitioned in blocks of size . The processors can only perform operations on data which are in their cache. The data can be transferred between the main memory and the cache in blocks of size .
I/O complexity
The complexity measure of the PEM model is the I/O complexity, which determines the number of parallel blocks transfers between the main memory and the cache. During a parallel block transfer each processor can transfer a block. So if processors load parallelly a data block of size form the main memory into their caches, it is considered as an I/O complexity of not . A program in the PEM model should minimize the data transfer between main memory and caches and operate as much as possible on the data in the caches.
Read/write conflicts
In the PEM model, there is no direct communication network between the P processors. The processors have to communicate indirectly over the main memory. If multiple processors try to access the same block in main memory concurrently read/write conflicts occur. Like in the PRAM model, three different variations of this problem are considered:
Concu |
https://en.wikipedia.org/wiki/Inhibitor%20cystine%20knot | An inhibitor cystine knot (also known as ICK or Knottin) is a protein structural motif containing three disulfide bridges. Knottins are one of three folds in the cystine knot motif; the other closely related knots are the growth factor cystine knot (GFCK) and the cyclic cystine knot (CCK; cyclotide). Types include a) cyclic mobius, b) cyclic bracelet, c) acyclic inhibitor knottins. Cystine knot motifs are found frequently in nature in a plethora of plants, animals, and fungi and serve diverse functions from appetite suppression to anti-fungal activity.
Along with the sections of polypeptide between them, two disulfides form a loop through which the third disulfide bond (linking the 3rd and 6th cysteine in the sequence) passes, forming a knot. The motif is common in invertebrate toxins such as those from arachnids and molluscs. The motif is also found in some inhibitor proteins found in plants, but the plant and animal motifs are thought to be a product of convergent evolution. The ICK motif is a very stable protein structure which is resistant to heat denaturation and proteolysis.
CK peptide components of venoms target voltage-gated ion channels but members of the family also act as antibacterial and haemolytic agents. Plant ICK proteins are often protease inhibitors.
Knottins have high stability to pH, heat, and enzymes. Because of their stability and their favorable pharmacodynamic properties, knottins are becoming increasingly popular as protein engineering scaffolds. Moreover, engineered knottins have shown significant promise as therapeutics, imaging agents, and targeting agents for chemotherapy.
The mammalian proteins Agouti signalling peptide and Agouti related peptide are the only known mammalian examples of this motif. Both are neuropeptides involved in cell signalling. The former is responsible for hair (fur) colouration.
The motif is similar to the cyclic cystine knot or cyclotide, but lacks the cyclisation of the polypeptide backbone which is presen |
https://en.wikipedia.org/wiki/Anomalon | In physics, an anomalon is a hypothetical type of nuclear matter that shows an anomalously large reactive cross section. They were first noticed in experimental runs in the early 1980s as short tracks in film emulsions or plastic leaf detectors connected to medium-energy particle accelerators. The direction of the tracks demonstrated that they were the results of reactions taking place within the accelerator targets, but they stopped so quickly in the detectors that no obvious explanation for their behavior could be offered. A flurry of theoretical explanations followed, but over time a series of follow-up experiments failed to find strong evidence for the anomalons, and active study of the topic largely ended by the late 1980s.
Description
Early particle accelerators generally consisted of three parts, the accelerator, a metal target, and some sort of detector. Detectors differed depending on the reactions being studied, but one class of inexpensive and useful detectors consisted of a large volume of photographic emulsion, often on individual plates, that would capture the particles as they moved through the stack. As the high-energy community moved to larger accelerators and exotic particles and reactions, new detectors were introduced that worked on different principles. The film technique remains in use today in certain fields; small versions can be flown on balloons, while larger versions can be placed in mines, both in order to capture rare but extremely high-energy cosmic rays.
By the late 1970s and early 1980s a generation of accelerators had been made obsolete by newer machines in terms of being useful for leading edge research. Still useful for other tasks, these older machines were turned to a wide variety of new studies. One particularly active area of research is collisions between higher mass particles, instead of fundamental particles like electrons or protons. Although the total energy of the reaction is the same, or lower, than it would be using l |
https://en.wikipedia.org/wiki/Sorbitan%20tristearate | Sorbitan tristearate is a nonionic surfactant. It is variously used as a dispersing agent, emulsifier, and stabilizer, in food and in aerosol sprays. As a food additive, it has the E number E492. Brand names for polysorbates include Alkest, Canarcel, and Span. The consistency of sorbitan tristearate is waxy; its color is light cream to tan.
See also
Sorbitan monostearate (Span 60) |
https://en.wikipedia.org/wiki/REBASE%20%28database%29 | In molecular biology, REBASE is a database of information about restriction enzymes and DNA methyltransferases. REBASE contains an extensive set of references, sites of recognition and cleavage, sequences and structures. It also contains information on the commercial availability of each enzyme. REBASE is one of the longest running biological databases having its roots in a collection of restriction enzymes maintained by Richard J. Roberts since before 1980. Since that time there have been regular descriptions of the resource in the journal Nucleic Acids Research.
See also
Restriction enzymes
DNA methyltransferases |
https://en.wikipedia.org/wiki/Lorcon | lorcon (acronym for Loss Of Radio CONnectivity) is an open source network tool. It is a library for injecting 802.11 (WLAN) frames, capable of injecting via multiple driver frameworks, without the need to change the application code. Lorcon is built by patching the third-party MadWifi-driver for cards based on the Qualcomm Atheros wireless chipset.
The project is maintained by Joshua Wright and Michael Kershaw ("dragorn"). |
https://en.wikipedia.org/wiki/Pliofilm | Pliofilm was a plastic wrap made by the Goodyear Tire and Rubber Company at plants in the US state of Ohio. Invented in the early 1930s, it was made by dissolving rubber in a benzene solvent and treating it with gaseous hydrochloric acid. Pliofilm was more stable in a range of humidities than earlier cellulose-based wraps and became popular as a food wrap. Its manufacture exposed workers to carcinogenic benzene and, when an additive was used to improve durability, caused dermatitis.
Production of Pliofilm was hampered during World War II because the Japanese occupation of much of Southeast Asia cut off much of the rubber supply. During the war years production was given over entirely to military purposes, with Pliofilm being used to wrap machinery and to waterproof firearms. After the war a plant was opened in Wolverhampton, England, and commercial production continued until the late 1980s.
Manufacture
Pliofilm is a transparent film made of rubber hydrochloride. It is impermeable to water and water vapour and non-flammable.
Pliofilm was manufactured by dissolving natural rubber in the solvent benzene. The solution was kept in a tank at around and treated with gaseous hydrochloric acid. The material was then neutralised with an alkali. The product was cast as a sheet on an endless belt which passed through a dryer that drove off the solvent. The finished product was around 30% chlorine. It could be made thinner by stretching whilst being heated and thicknesses of were sold. Thicker sheets could be produced by laminating the product, combining several sheets with the use of rubber cement.
History and uses
Pliofilm was invented by Harold J. Osterhof at the Goodyear Tire and Rubber Company in the early 1930s and first marketed in 1934. The product found early use as a food wrap, its very low oxygen permeability helping to keep foods fresh. Its clinginess and better stability at a range of humidities was an advantage over the cellulose wrapping films us |
https://en.wikipedia.org/wiki/SiFive | SiFive, Inc. is a fabless semiconductor company and provider of commercial RISC-V processor IP and silicon chips based on the RISC-V instruction set architecture (ISA). SiFive's products include cores, SoCs, IPs, and development boards.
SiFive is one of the first companies to produce a chip that implements the RISC-V ISA.
History
SiFive was founded in 2015 by Krste Asanović, Yunsup Lee, and Andrew Waterman, three researchers from the University of California Berkeley. On November 29, 2016, SiFive released the Freedom Everywhere 310 SoC and the HiFive development board, making SiFive the first company to produce a chip that implements the RISC-V ISA, although universities have produced earlier RISC-V processors.
In August 2017, SiFive hired Naveed Sherwani as CEO. In October, SiFive did a limited release of its U54-MC, reportedly the world's first RISC-V based 64-bit quad-core CPU to support fully featured operating systems like Linux.
In June 2018, SiFive acquired Open-Silicon for an undisclosed amount and retained their design capabilities for specialized chips, also called application-specific integrated circuits, or ASICs.
In February 2018, SiFive released the HiFive Unleashed, a development board containing a 64-bit SoC with four U54 cores.
In September 2020, the company announced Patrick Little as the new CEO.
In October 2020, SiFive released the HiFive Unmatched, a Mini-ITX development board with four U74-MC cores, one S7 core, 8GB DDR4 RAM, four USB 3.2 Gen1 ports, one PCI Express x16 slot, one PCIe Gen3 x4, one microSD card slot, and a Gigabit Ethernet. In April 2021, the company also taped out its first system-on-chip on TSMC's N5 process technology, making it the first RISC-V-based device to be made using a 5 nm node.
In June 2021, Canonical announced its Ubuntu operating system supports the HiFive Unmatched and HiFive Unleashed, and the Barcelona Supercomputing Center collaborated with Codeplay Software and SiFive to implement support for the RIS |
https://en.wikipedia.org/wiki/Multiple%20Spanning%20Tree%20Protocol | The Multiple Spanning Tree Protocol (MSTP) and algorithm, provides both simple and full connectivity assigned to any given virtual LAN (VLAN) throughout a bridged local area network. MSTP uses bridge protocol data unit (BPDUs) to exchange information between spanning-tree compatible devices, to prevent loops in each Multiple Spanning Tree instance (MSTI) and in the common and internal spanning tree (CIST), by selecting active and blocked paths. This is done as well as in Spanning Tree Protocol (STP) without the need of manually enabling backup links and getting rid of switching loop danger.
Moreover, MSTP allows frames/packets assigned to different VLANs to follow separate paths, each based on an independent MSTI, within MST regions composed of local area networks (LANs) and MST bridges. These regions and the other bridges and LANs are connected into a single common spanning tree (CST).
History and motivation
It was originally defined in IEEE 802.1s as an amendment to 802.1Q, 1998 edition and later merged into IEEE 802.1Q-2005 Standard, clearly defines an extension or an evolution of Radia Perlman's Spanning Tree Protocol (STP) and the Rapid Spanning Tree Protocol (RSTP). It has some similarities with Cisco Systems' Multiple Instances Spanning Tree Protocol (MISTP), but there are some differences.
The original STP and RSTP work on the physical link level, preventing bridge loops when redundant paths are present. However, when a LAN is virtualized using VLAN trunking, each physical link represents multiple logical connections. Blocking a physical link blocks all its logical links and forces all traffic through the remaining physical links within the spanning tree. Redundant links cannot be utilized at all. Moreover, without careful network design, seemingly redundant links on the physical level may be used to connect different VLANs and blocking any of them may disconnect one or more VLANs, causing bad paths.
Instead, MSTP provides a potentially better utiliza |
https://en.wikipedia.org/wiki/774%E2%80%93775%20carbon-14%20spike | The 774–775 carbon-14 spike is an observed increase of around 1.2% in the concentration of the radioactive carbon-14 isotope in tree rings dated to 774 or 775 CE, which is about 20 times higher than the normal year-to-year variation of radiocarbon in the atmosphere. It was discovered during a study of Japanese cedar tree-rings, with the year of occurrence determined through dendrochronology. A surge in beryllium isotope , detected in Antarctic ice cores, has also been associated with the 774–775 event. The 774–775 CE carbon-14 spike is one of the several Miyake events and it produced the largest and most rapid rise in carbon-14 ever recorded.
The event appears to have been global, with the same carbon-14 signal found in tree rings from Germany, Russia, the United States, Finland, and New Zealand.
The signal exhibits a sharp increase of around 1.2% followed by a slow decline, which is consistent with an instant production of carbon-14 in the atmosphere, indicating that the event was short in duration. The globally averaged production of carbon-14 for this event is .
Hypotheses
Several possible causes of the event have been considered.
The "red crucifix" recorded by the Anglo-Saxon Chronicle has been variously hypothesised to have been a supernova or the aurora borealis.
In China, there is only one clear reference to an aurora in the mid-770s, on 12 January 776. However, an anomalous "thunderstorm" was recorded for 775.
The most widely accepted theory is that the event was caused by a solar particle event (SPE) from a very strong solar flare, perhaps the strongest known.
Another proposed origin, involving a gamma-ray burst, is regarded as unlikely, because the event was also observed in isotopes and .
Frequency of similar events
The event of 774 is the strongest spike over the last 11,000 years in the record of cosmogenic isotopes, but several other events of the same kind (Miyake events) have occurred during the Holocene epoch. The 993–994 carbon-14 spike wa |
https://en.wikipedia.org/wiki/British%20Biophysical%20Society | The British Biophysical Society is a scientific society that exists to encourage and disseminate developments in the application of physical and chemical concepts to biological systems. It was founded in 1960 following a report from a Working Party on Biophysics and Biophysical Chemistry initiated by the Council of the then Faraday Society of London. The current Chair is Olwyn Byron.
History
The first full meeting of the Working Party on Biophysics and Biophysical Chemistry was held on 4 February 1960. The party included D D Eley, L H Gray, A F Huxley, J C Kendrew, C F A Pantin, R D Preston, J T Randall, F J W Roughton and P M B Walker.
The first meeting of the British Biophysical Society was held at King's College (London) and was organised by J T Randall. The birth of the BBS can be said to date from this inaugural meeting held on 19 and 20 December 1960. The meeting took the form of two symposia on Comparative Studies of Muscular Contraction and on the Structure of Ribonucleic Acid, together with sessions for contributed papers. Minutes of the Steering Committee held on 8 December record that there had already been 183 applications to join the Society and 177 to attend the meeting. By the end of 1960, the membership totaled 224. At the King's College meeting W T Astbury and A V Hill were elected Honorary members.
The early years
The first Steering Committee of the BBS, J C Kendrew became the first Honorary Secretary and D D Eley Meetings Secretary, and the Committee elected J T Randall as its first Chairman and P B M Walker as Honorary Treasurer. Other committee members were S Brenner, J A V Butler, A F Huxley, R D Keynes, R D Preston, J W S Pringle, F J W Roughton and J T Weiss.
From its inception the British Biophysical Society embraced a wide range of topics in Biology. The first major scientific meeting of the British Biophysical Society at King’s College, London (on The Structure of Globular Proteins and The Function of Proteins) and a report on pr |
https://en.wikipedia.org/wiki/Gynodioecy | Gynodioecy is a rare breeding system that is found in certain flowering plant species in which female and hermaphroditic plants coexist within a population. Gynodioecy is the evolutionary intermediate between hermaphroditism (exhibiting both female and male parts) and dioecy (having two distinct morphs: male and female).
Gynodioecy is sometimes considered a mixed breeding system comparable with trioecy and androdioecy. It is also considered a dimorphic sexual system alongside dioecy and androdioecy.
Gynodioecy occurs as a result of a genetic mutation that inhibits a hermaphroditic plant from producing pollen, while keeping the female reproductive parts intact. Gynodioecy is extremely rare, with fewer than 1% of angiosperm species exhibiting the breeding system. Some notable taxa that exhibit a gynodioecious mating system include Beta vulgaris (wild beet), Lobelia siphilitica, Silene, and Lamiaceae.
Evolution
Gynodioecy is often referred to as the evolutionary intermediate state between hermaphroditism and dioecy, however there is no evidence it is an intermediate state in animals. Gynodioecy has been investigated by biologists dating as far back as to Charles Darwin.
Gynodioecy can evolve from hermaphroditism due to certain environmental factors. If enough resources in a population are allocated to the female functions in a hermaphroditic species, gynodioecy will ensue. On the other hand, if more of those resources favor a hermaphrodite's male functions, androdioecy will result. A high rate of self-pollination in a population facilitates the maintenance of gynodioecy by increasing the inbreeding costs for hermaphrodites. Thus, as the rate of inbreeding increases in a population, the more likely gynodioecy is to occur.
Hermaphroditic plants may be able to reproduce on their own but in many species they are self-incompatible. Research has shown that a species can be either gynodioecious or self-incompatible, but very rarely is there a co-occurrence between the |
https://en.wikipedia.org/wiki/Dimensional%20reduction | Dimensional reduction is the limit of a compactified theory where the size of the compact dimension goes to zero. In physics, a theory in D spacetime dimensions can be redefined in a lower number of dimensions d, by taking all the fields to be independent of the location in the extra D − d dimensions.
For example, consider a periodic compact dimension with period L. Let x be the coordinate along this dimension. Any field can be described as a sum of the following terms:
with An a constant. According to quantum mechanics, such a term has momentum nh/L along x, where h is Planck's constant. Therefore, as L goes to zero, the momentum goes to infinity, and so does the energy, unless n = 0. However n = 0 gives a field which is constant with respect to x. So at this limit, and at finite energy, will not depend on x.
This argument generalizes. The compact dimension imposes specific boundary conditions on all fields, for example periodic boundary conditions in the case of a periodic dimension, and typically Neumann or Dirichlet boundary conditions in other cases. Now suppose the size of the compact dimension is L; then the possible eigenvalues under gradient along this dimension are integer or half-integer multiples of 1/L (depending on the precise boundary conditions). In quantum mechanics this eigenvalue is the momentum of the field, and is therefore related to its energy. As L → 0 all eigenvalues except zero go to infinity, and so does the energy. Therefore, at this limit, with finite energy, zero is the only possible eigenvalue under gradient along the compact dimension, meaning that nothing depends on this dimension.
Dimensional reduction also refers to a specific cancellation of divergences in Feynman diagrams. It was put forward by Amnon Aharony, Yoseph Imry, and Shang-keng Ma who proved in 1976 that "to all orders in perturbation expansion, the critical exponents in a d-dimensional (4 < d < 6) system with short-range exchange and a random quenched field are t |
https://en.wikipedia.org/wiki/Pulse-Doppler%20signal%20processing | Pulse-Doppler signal processing is a radar and CEUS performance enhancement strategy that allows small high-speed objects to be detected in close proximity to large slow moving objects. Detection improvements on the order of 1,000,000:1 are common. Small fast moving objects can be identified close to terrain, near the sea surface, and inside storms.
This signal processing strategy is used in pulse-Doppler radar and multi-mode radar, which can then be pointed into regions containing a large number of slow-moving reflectors without overwhelming computer software and operators. Other signal processing strategies, like moving target indication, are more appropriate for benign clear blue sky environments.
It is also used to measure blood flow in Doppler ultrasonography.
Environment
Pulse-Doppler begins with coherent pulses transmitted through an antenna or transducer.
There is no modulation on the transmit pulse. Each pulse is a perfectly clean slice of a perfect coherent tone. The coherent tone is produced by the local oscillator.
There can be dozens of transmit pulses between the antenna and the reflector. In a hostile environment, there can be millions of other reflections from slow moving or stationary objects.
Transmit pulses are sent at the pulse repetition frequency.
Energy from the transmit pulses propagate through space until they are disrupted by reflectors. This disruption causes some of the transmit energy to be reflected back to the radar antenna or transducer, along with phase modulation caused by motion. The same tone that is used to generate the transmit pulses is also used to down-convert the received signals to baseband.
The reflected energy that has been down-converted to baseband is sampled.
Sampling begins after each transmit pulse is extinguished. This is the quiescent phase of the transmitter.
The quiescent phase is divided into equally spaced sample intervals. Samples are collected until the radar begins to fire another transmit pulse.
|
https://en.wikipedia.org/wiki/Quasi-isometry | In mathematics, a quasi-isometry is a function between two metric spaces that respects large-scale geometry of these spaces and ignores their small-scale details. Two metric spaces are quasi-isometric if there exists a quasi-isometry between them. The property of being quasi-isometric behaves like an equivalence relation on the class of metric spaces.
The concept of quasi-isometry is especially important in geometric group theory, following the work of Gromov.
Definition
Suppose that is a (not necessarily continuous) function from one metric space to a second metric space . Then is called a quasi-isometry from to if there exist constants , , and such that the following two properties both hold:
For every two points and in , the distance between their images is up to the additive constant within a factor of of their original distance. More formally:
Every point of is within the constant distance of an image point. More formally:
The two metric spaces and are called quasi-isometric if there exists a quasi-isometry from to .
A map is called a quasi-isometric embedding if it satisfies the first condition but not necessarily the second (i.e. it is coarsely Lipschitz but may fail to be coarsely surjective). In other words, if through the map, is quasi-isometric to a subspace of .
Two metric spaces M1 and M2 are said to be quasi-isometric, denoted , if there exists a quasi-isometry .
Examples
The map between the Euclidean plane and the plane with the Manhattan distance that sends every point to itself is a quasi-isometry: in it, distances are multiplied by a factor of at most . Note that there can be no isometry, since, for example, the points are of equal distance to each other in Manhattan distance, but in the Euclidean plane, there are no 4 points that are of equal distance to each other.
The map (both with the Euclidean metric) that sends every -tuple of integers to itself is a quasi-isometry: distances are preserved exactly, and every real t |
https://en.wikipedia.org/wiki/Caldimicrobium%20rimae | Caldimicrobium rimae is an extremely thermophilic, strictly anaerobic and facultatively chemolithoautotrophic bacterium from the genus of Caldimicrobium which has been isolated from the Treshchinnyi Spring from Uzon Caldera in Russia.
Origins of taxonomical branch
Caldimicrobium rimae varies from its family of Thermodesulfobacteriaceae as it is not capable of oxidizing organic acids or alcohols and use sulfur as an electron receptor. |
https://en.wikipedia.org/wiki/Wetland | Wetlands, or simply a wetland, is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The primary factor that distinguishes wetlands from terrestrial land forms or water bodies is the characteristic vegetation of aquatic plants, adapted to the unique anoxic hydric soils. Wetlands are considered among the most biologically diverse of all ecosystems, serving as home to a wide range of plant and animal species. Methods for assessing wetland functions, wetland ecological health, and general wetland condition have been developed for many regions of the world. These methods have contributed to wetland conservation partly by raising public awareness of the functions some wetlands provide. Constructed wetlands are designed and built to treat municipal and industrial wastewater as well as to divert stormwater runoff. Constructed wetlands may also play a role in water-sensitive urban design.
Wetlands occur naturally on every continent. The water in wetlands is either freshwater, brackish or saltwater. The main wetland types are classified based on the dominant plants and/or the source of the water. For example, marshes are wetlands dominated by emergent vegetation such as reeds, cattails and sedges; swamps are ones dominated by woody vegetation such as trees and shrubs (although reed swamps in Europe are dominated by reeds, not trees).
Examples of wetlands classified by their sources of water include tidal wetlands (oceanic tides), estuaries (mixed tidal and river waters), floodplains (excess water from overflowed rivers or lakes), springs, seeps and fens (groundwater discharge out onto the surface), and bogs and vernal ponds (rainfall or meltwater). Some wetlands have multiple types of plants and are fed by multiple sources of water, making them difficult to classify. The world's largest wetlands incl |
https://en.wikipedia.org/wiki/KCNK5 | Potassium channel subfamily K member 5 is a protein that in humans is encoded by the KCNK5 gene.
This gene encodes K2P5.1, one of the members of the superfamily of potassium channel proteins containing two pore-forming P domains. The message for this gene is mainly expressed in the cortical distal tubules and collecting ducts of the kidney. The protein is highly sensitive to external pH and this, in combination with its expression pattern, suggests it may play an important role in renal potassium transport.
See also
Tandem pore domain potassium channel |
https://en.wikipedia.org/wiki/Panorama%20Software | Panorama Software is a Canadian software and consulting company specializing in business intelligence. The company was founded by Rony Ross in Israel in 1993; it relocated its headquarters to Toronto, Canada in 2003.
Panorama sold its online analytical processing (OLAP) technology to Microsoft in 1996, which was built into Microsoft OLAP Services and later SQL Server Analysis Services, an integrated component of Microsoft SQL Server.
Products
The company’s main product is a business intelligence (BI) suite named Necto.
Before 2011 it had a product called NovaView.
Necto offers data mining and report generation, allowing custom views of the data without having to wait to run a report. It lets users create collaborative "workboards" and visual presentations. The users are able discover those who are attempting to analyze similar data sets. The company contends this focus on social analysis leads, starting with business data and connecting it with the people who are involved in this data.
Necto is a BI application based upon understanding of user behavior, one-click reporting, and collaborative decision making. It supports social sharing of data, similar to sharing found on consumer oriented social networking sites. Data analysis is treated as "conversations" which can themselves be followed and analyzed. Panorama encourages Necto enterprise users to form cross-departmental teams based on data research behaviors. It allows tracking of user behavior and making corresponding adjustments.
Necto includes analytics, custom reporting, intuitive dashboards, and integration with Microsofttechnology. It can use data sources including spreadsheets, in-memory, OLAP, or relational databases. Integration on Microsoft Azure and optimization with Microsoft SQL Server 2012 platform is also available. Necto integrates with SharePoint. It can be scaled up to manage thousands of users and several terabytes of data.
Panorama and Microsoft
Panorama Software is the original develope |
https://en.wikipedia.org/wiki/Task%20analysis%20environment%20modeling%20simulation | Task Analysis, Environment Modeling, and Simulation (TAEMS or TÆMS) is a problem domain independent modeling language used to describe the task structures and the problem-solving activities of intelligent agents in a multi-agent environment.
The intelligent agent operates in environments where:
responses by specific deadlines may be required
the information required for the optimal performance of a computational task may not be available
the results of the computations of multiple agents to interdependent subproblems may need to be aggregated together in order to solve a high-level goal
an agent may be contributing concurrently to the solution of multiple goals
Tasks
The modeling language represents a task structure so that an intelligent agent can reason about its potential actions in the context of its working environment. The intelligent agent needs to determine what goals can and should be achieved, and what actions are needed to achieve those goals. This includes determining the implications of those actions, and of actions performed by other agents in the environment.
The modeling language represents a task structure including the quantitative representation of complex task interrelationships, with the task structure model divided into generative, objective, and subjective viewpoints. The generative viewpoint describes the statistical characteristics required to generate the objective and subjective episodes in an environment; it is a workload generator. The objective viewpoint is the actual, real, instantiated task structures that are present in an episode. The subjective viewpoint is the view that the agents have of objective reality.
Coordination
Coordination of agents is accomplished by the Generalized Partial Global Planning (GPGP) family of algorithms that are used to respond to particular features of the task structure. GPGP is a cooperative (team-oriented) coordination component that is built of modular mechanisms that work in conjunction w |
https://en.wikipedia.org/wiki/Selection%20principle | In mathematics, a selection principle is a rule asserting
the possibility of obtaining mathematically significant objects by
selecting elements from given sequences of sets. The theory of selection principles
studies these principles and their relations to other mathematical properties.
Selection principles mainly describe covering properties,
measure- and category-theoretic properties, and local properties in
topological spaces, especially function spaces. Often, the
characterization of a mathematical property using a selection
principle is a nontrivial task leading to new insights on the
characterized property.
The main selection principles
In 1924, Karl Menger
introduced the following basis property for metric spaces:
Every basis of the topology contains a sequence of sets with vanishing
diameters that covers the space. Soon thereafter,
Witold Hurewicz
observed that Menger's basis property is equivalent to the
following selective property: for every sequence of open covers of the space,
one can select finitely many open sets from each cover in the sequence, such that the family of all selected sets covers the space.
Topological spaces having this covering property are called Menger spaces.
Hurewicz's reformulation of Menger's property was the first important
topological property described by a selection principle.
Let and be classes of mathematical objects.
In 1996, Marion Scheepers
introduced the following selection hypotheses,
capturing a large number of classic mathematical properties:
: For every sequence of elements from the class , there are elements such that .
: For every sequence of elements from the class , there are finite subsets such that .
In the case where the classes and consist of covers of some ambient space, Scheepers also introduced the following selection principle.
: For every sequence of elements from the class , none containing a finite subcover, there are finite subsets such that .
Later, Boaz Tsaban id |
https://en.wikipedia.org/wiki/Type%20II%20cytokine%20receptor | Type II cytokine receptors, also commonly known as class II cytokine receptors, are transmembrane proteins that are expressed on the surface of certain cells. They bind and respond to a select group of cytokines including interferon type I, interferon type II, interferon type III. and members of the interleukin-10 family These receptors are characterized by the lack of a WSXWS motif which differentiates them from type I cytokine receptors.
Structure
Typically type II cytokine receptors are heterodimers or multimers with a high and a low affinity component. These receptors are related predominantly by sequence similarities in their extracellular portions that are composed of tandem Ig-like domains. The structures for the extracellular domains of the receptors for interferon types, I, II, and III are all known.
Type II cytokine receptors are tyrosine-kinase-linked receptors. The intracellular domain of type II cytokine receptors is typically associated with a tyrosine kinase belonging to the Janus kinase (JAK family). Binding of the receptor typically leads to activation of the canonical JAK/STAT signaling pathway.
Types
Type II cytokine receptors include those that bind interferons and those that bind members of the interleukin-10 family (interleukin-10, interleukin-20, interleukin-22, and interleukin-28). Expression of specific receptor varieties is highly variable across tissue types with some receptors being ubiquitously expressed and some receptors only expressed in specific tissues.
Interferon receptors
The interferon receptor is a molecule displayed on the surface of cells which interacts with extracellular interferons. Class II cytokine receptors bind type I, type II, and type III interferons. Type I interferons play important roles in both the adaptive and innate immune responses, prevent proliferation of pathogens, and have antiviral activities. Type II interferons help to modulate the immune system’s response to pathogens, and these interferons also r |
https://en.wikipedia.org/wiki/Random-access%20memory | Random-access memory (RAM; ) is a form of electronic computer memory that can be read and changed in any order, typically used to store working data and machine code. A random-access memory device allows data items to be read or written in almost the same amount of time irrespective of the physical location of data inside the memory, in contrast with other direct-access data storage media (such as hard disks, CD-RWs, DVD-RWs and the older magnetic tapes and drum memory), where the time required to read and write data items varies significantly depending on their physical locations on the recording medium, due to mechanical limitations such as media rotation speeds and arm movement.
RAM contains multiplexing and demultiplexing circuitry, to connect the data lines to the addressed storage for reading or writing the entry. Usually more than one bit of storage is accessed by the same address, and RAM devices often have multiple data lines and are said to be "8-bit" or "16-bit", etc. devices.
In today's technology, random-access memory takes the form of integrated circuit (IC) chips with MOS (metal–oxide–semiconductor) memory cells. RAM is normally associated with volatile types of memory where stored information is lost if power is removed. The two main types of volatile random-access semiconductor memory are static random-access memory (SRAM) and dynamic random-access memory (DRAM).
Non-volatile RAM has also been developed
and other types of non-volatile memories allow random access for read operations, but either do not allow write operations or have other kinds of limitations on them. These include most types of ROM and a type of flash memory called NOR-Flash.
Use of semiconductor RAM dated back to 1965, when IBM introduced the monolithic (single-chip) 16-bit SP95 SRAM chip for their System/360 Model 95 computer, and Toshiba used discrete DRAM memory cells for its 180-bit Toscal BC-1411 electronic calculator, both based on bipolar transistors. While it offered hi |
https://en.wikipedia.org/wiki/Host%20signal%20processing | Host signal processing (HSP) is a term used in computing to describe hardware such as a modem or printer which is emulated (to various degrees) in software. Intel refers to the technology as native signal processing (NSP). HSP replaces dedicated DSP or ASIC hardware by using the general purpose CPU of the host computer.
Modems using HSP are known as winmodems (a term trademarked by 3COM / USRobotics, but genericized) or softmodems. Printers using HSP are known as GDI printers (after the MS Windows GDI software interface), winprinters (named after winmodems) or softprinters.
The Apple II Disk II floppy drive used the host CPU to process drive control signals, instead of a microcontroller. This instance of HSP predates the usage of the terms HSP and NSP.
In the mid- to late-1990s, Intel pursued native signal processing technology to improve multimedia handling. According to testimony by Intel, Microsoft opposed development of NSP because the technology could reduce the necessity of the Microsoft Windows operating system. Intel claims to have terminated development of NSP because of threats from Microsoft. |
https://en.wikipedia.org/wiki/Synchronous%20serial%20communication | Synchronous serial communication describes a serial communication protocol in which "data is sent in a continuous stream at constant rate."
Synchronous communication requires that the clocks in the transmitting and receiving devices are synchronized – running at the same rate – so the receiver can sample the signal at the same time intervals used by the transmitter. No start or stop bits are required. For this reason "synchronous communication permits more information to be passed over a circuit per unit time" than asynchronous serial communication. Over time the transmitting and receiving clocks will tend to drift apart, requiring resynchronization.
Byte-oriented protocols
Early synchronous protocols were byte-oriented protocols, where synchronization was maintained by transmitting a sequence of synchronous idle characters when the line was not actively transmitting data or transparently within a long transmission block. A certain number of idles were sent prior to each transmission. The IBM Binary Synchronous protocol (Bisync) is still in use, Other examples of byte-oriented protocols are IBM's Synchronous transmit-receive (STR), and Digital Data Communications Message Protocol (DDCMP) from Digital Equipment Corporation. Other computer manufacturers often offered similar protocols, differing mainly in small details.
Bit-oriented protocols
Bit-oriented protocols are synchronous protocols that view the transmitted data as a stream of bits with no semantics, or meaning. Control codes are defined in terms of bit sequences instead of characters. Synchronization is maintained on an idle line by transmitting a predefined sequence of bits. Synchronous Data Link Control (SDLC) specifies that a station continue transmitting a sequence of '1' bits on an idle line. Data to be transmitted on an idle line is prefixed with a special bit sequence '01111110'b, called a flag. SDLC was the first bit-oriented protocol developed, and it was later adopted by the Internati |
https://en.wikipedia.org/wiki/ACLAME | ACLAME (The CLAssification of Mobile genetic Elements) is a database of sequenced mobile genetic elements.
See also
Gypsy (database)
Mobile genetic elements |
https://en.wikipedia.org/wiki/C1QL1 | The complement component 1, q subcomponent-like 1 (or C1QL1) is encoded by a gene located at chromosome 17q21.31. It is a secreted protein and is 258 amino acids in length.
The protein is widely expressed but its expression is highest in the brain and may also be involved in regulation of motor control.
The pre-mRNA of this protein is subject to RNA editing.
Protein function
Its physiological function is unknown. It is a member of the C1Q domain proteins which have important signalling roles in inflammation and in adaptive immunity.
RNA editing
Editing type
The pre-mRNA of this protein is subject to A to I RNA editing, which is catalyzed by a family of adenosine deaminases acting on RNA (ADARs) that specifically recognize adenosines within double-stranded regions of pre-mRNAs and deaminate them to inosine. Inosines are recognised as guanosine by the cell's translational machinery. There are three members of the ADAR family: ADARs 1-3, with ADAR 1 and ADAR 2 being the only enzymatically active members. ADAR 3 is thought to have a regulatory role in the brain. ADAR 1 and ADAR 2 are widely expressed in tissues while ADAR 3 is restricted to the brain. The double-stranded regions of RNA are formed by base-pairing between residues in a region complementary to the region of the editing site. This complementary region is usually found in a neighbouring intron but can also be located in an exonic sequence. The region that pairs with the editing region is known as an Editing Complementary Sequence (ECS).
Editing sites
The candidate editing sites were determined experimentally by comparison of cDNA sequences and genomically encoded DNA from the same individual to avoid single nucleotide polymorphisms (SNPs). Two of the three editing sites found in mouse gene were found in the human transcript.
However, only the Q/R site was detected in all RNA, with the T/A site detected just once. Both sites are found within exon 1.
Q/R site
This site is found in exon 1 at |
https://en.wikipedia.org/wiki/Mathematical%20chemistry | Mathematical chemistry is the area of research engaged in novel applications of mathematics to chemistry; it concerns itself principally with the mathematical modeling of chemical phenomena. Mathematical chemistry has also sometimes been called computer chemistry, but should not be confused with computational chemistry.
Major areas of research in mathematical chemistry include chemical graph theory, which deals with topology such as the mathematical study of isomerism and the development of topological descriptors or indices which find application in quantitative structure-property relationships; and chemical aspects of group theory, which finds applications in stereochemistry and quantum chemistry. Another important area is molecular knot theory and circuit topology that describe the topology of folded linear molecules such as proteins and Nucleic Acids.
The history of the approach may be traced back to the 19th century. Georg Helm published a treatise titled "The Principles of Mathematical Chemistry: The Energetics of Chemical Phenomena" in 1894. Some of the more contemporary periodical publications specializing in the field are MATCH Communications in Mathematical and in Computer Chemistry, first published in 1975, and the Journal of Mathematical Chemistry, first published in 1987. In 1986 a series of annual conferences MATH/CHEM/COMP taking place in Dubrovnik was initiated by the late Ante Graovac.
The basic models for mathematical chemistry are molecular graph and topological index.
In 2005 the International Academy of Mathematical Chemistry (IAMC) was founded in Dubrovnik (Croatia) by Milan Randić. The Academy has 82 members (2009) from all over the world, including six scientists awarded with a Nobel Prize.
See also
Bibliography
Molecular Descriptors for Chemoinformatics, by R. Todeschini and V. Consonni, Wiley-VCH, Weinheim, 2009.
Mathematical Chemistry Series, by D. Bonchev, D. H. Rouvray (Eds.), Gordon and Breach Science Publisher, Amsterdam, 2000 |
https://en.wikipedia.org/wiki/Lam%C3%A9%27s%20stress%20ellipsoid | Lamé's stress ellipsoid is an alternative to Mohr's circle for the graphical representation of the stress state at a point. The surface of the ellipsoid represents the locus of the endpoints of all stress vectors acting on all planes passing through a given point in the continuum body. In other words, the endpoints of all stress vectors at a given point in the continuum body lie on the stress ellipsoid surface, i.e., the radius-vector from the center of the ellipsoid, located at the material point in consideration, to a point on the surface of the ellipsoid is equal to the stress vector on some plane passing through the point. In two dimensions, the surface is represented by an ellipse.
Once the equations of the ellipsoid is known, the magnitude of the stress vector can then be obtained for any plane passing through that point.
To determine the equation of the stress ellipsoid we consider the coordinate axes taken in the directions of the principal axes, i.e., in a principal stress space. Thus, the coordinates of the stress vector on a plane with normal unit vector passing through a given point is represented by
And knowing that is a unit vector we have
which is the equation of an ellipsoid centered at the origin of the coordinate system, with the lengths of the semiaxes of the ellipsoid equal to the magnitudes of the principal stresses, i.e. the intercepts of the ellipsoid with the principal axes are .
The first stress invariant is directly proportional to the sum of the principal radii of the ellipsoid.
The second stress invariant is directly proportional to the sum of the three principal areas of the ellipsoid. The three principal areas are the ellipses on each principal plane.
The third stress invariant is directly proportional to the volume of the ellipsoid.
If two of the three principal stresses are numerically equal the stress ellipsoid becomes an ellipsoid of revolution. Thus, two principal areas are ellipses and the third is a circle.
If a |
https://en.wikipedia.org/wiki/Active%20record%20pattern | In software engineering, the active record pattern is an architectural pattern. It is found in software that stores in-memory object data in relational databases. It was named by Martin Fowler in his 2003 book Patterns of Enterprise Application Architecture. The interface of an object conforming to this pattern would include functions such as Insert, Update, and Delete, plus properties that correspond more or less directly to the columns in the underlying database table.
The active record pattern is an approach to accessing data in a database. A database table or view is wrapped into a class. Thus, an object instance is tied to a single row in the table. After creation of an object, a new row is added to the table upon save. Any object loaded gets its information from the database. When an object is updated, the corresponding row in the table is also updated. The wrapper class implements accessor methods or properties for each column in the table or view.
This pattern is commonly used by object persistence tools and in object–relational mapping (ORM). Typically, foreign key relationships will be exposed as an object instance of the appropriate type via a property.
Implementations
Implementations of the concept can be found in various frameworks for many programming environments. For example, if there is a table parts in a database with columns name (string type) and price (number type), and the Active Record pattern is implemented in the class Part, the pseudo-code
will create a new row in the parts table with the given values, and is roughly equivalent to the SQL command
INSERT INTO parts (name, price) VALUES ('Sample part', 123.45);
Conversely, the class can be used to query the database:
This will find a new Part object based on the first matching row from the parts table whose name column has the value "gearbox". The SQL command used might be similar to the following, depending on the SQL implementation details of the database:
SELECT * FROM parts WHERE |
https://en.wikipedia.org/wiki/Peripharyngeal%20space | The peripharyngeal space is a space in the neck.
It can be split into the retropharyngeal space and the parapharyngeal space. |
https://en.wikipedia.org/wiki/Glycosynthase | The term glycosynthase refers to a class of proteins that have been engineered to catalyze the formation of a glycosidic bond. Glycosynthase are derived from glycosidase enzymes, which catalyze the hydrolysis of glycosidic bonds. They were traditionally formed from retaining glycosidase by mutating the active site nucleophilic amino acid (usually an aspartate or glutamate) to a small non-nucleophilic amino acid (usually alanine or glycine). More modern approaches use directed evolution to screen for amino acid substitutions that enhance glycosynthase activity.
The first glycosynthase
Two discoveries led to the development of glycosynthase enzymes. The first was that a change of the active site nucleophile of a glycosidase from a carboxylate to another amino acid resulted in a properly folded protein that had no hydrolase activity.
The second discovery was that some glycosidase enzymes were able to catalyze the hydrolysis of glycosyl fluorides that had the incorrect anomeric configuration. The enzymes underwent a transglycosidation reaction to form a disaccharide, which was then a substrate for hydrolase activity.
The first reported glycosynthase was a mutant of the Agrobacterium sp. β-glucosidase / galactosidase in which the nucleophile glutamate 358 was mutated to an alanine by site directed mutagenesis. When incubated with α-glycosyl fluorides and an acceptor sugar it was found to catalyze the transglycosidation reaction without any hydrolysis. This glycosynthase was used to synthesize a series of di- and trisaccharide products with yields between 64% and 92%.
Reaction mechanism
The mechanism of a glycosynthase is similar to the hydrolysis reaction of retaining glycosidases except no covalent-enzyme intermediate is formed. Mutation of the active site nucleophile to a non-nucleophilic amino acid prevents the formation of a covalent intermediate. An activated glycosyl donor with a good anomeric-leaving group (often a fluorine) is required. The leavin |
https://en.wikipedia.org/wiki/Explorer%2036 | Explorer 36 (also called GEOS 2 or GEOS B, acronym for Geodetic Earth Orbiting Satellite) was a NASA satellite launched as part of the Explorer program, being the second of the two satellites GEOS. Explorer 36 was launched on 11 January 1968 from Vandenberg Air Force Base, with Thor-Delta E1 launch vehicle.
Explorer 36 was a gravity-gradient stabilized, solar cell powered spacecraft that carried electronic and geodetic instrumentation.
Instruments
The geodetic instrumentation systems included:
C-Band Radar Transponder
Laser Tracking Reflector
Magnetometer
NASA Minitrack System
Optical Beacon System
Precipitating Electron Detector
Radio Doppler System
Radio Range/Rate System
SECOR Range Transponder
Non-geodetic systems included a laser detector and a Minitrack interferometer beacon. The objectives of the spacecraft were to optimize optical station visibility periods and to provide complementary data for inclination-dependent terms established by the Explorer 29 (GEOS 1) gravimetric studies. The spacecraft was placed into a retrograde orbit to accomplish these objectives. Operational problems occurred in the main power system, optical beacon flash system, and the spacecraft clock, and adjustments in scheduling resulted in nominal operations.
Experiments
C-Band Radar Transponder
The C-band radar system was used for experimental range radar calibration and data recording to determine the accuracy of the system for geometric and gravimetric investigations. For redundancy, two transponders, each operating on 5690-MHz (RCVR) and 765-MHz (XMTR) were carried on the spacecraft. One transponder had a 5-ms interval time delay, and the other had a near-zero internal delay that allowed for real-time identification by the C-band participants. The transponders were operated on a select-call basis to conserve spacecraft power. A C-band passive reflector was used in conjunction with the transponders for precise calibration of the internal time delay and to provide pas |
https://en.wikipedia.org/wiki/The%20Daily%20WTF | The Daily WTF (also called Worse Than Failure from February to December 2007) is a humorous blog dedicated to "Curious Perversions in Information Technology". The blog, run by Alex Papadimoulis, "offers living examples of code that invites the exclamation ‘WTF!?'" (What The Fuck!?) and "recounts tales of disastrous development, from project management gone spectacularly bad to inexplicable coding choices."
In addition to horror stories, The Daily WTF "serve[s] as [a] repositor[y] of knowledge and discussion forums for inquisitive web designers and developers" and has introduced several anti-patterns, including Softcoding, the Inner-Platform Effect, and IHBLRIA (Invented Here But Let's Reinvent It Anyway).
The site also has an associated "Edition Française", a French-language edition headed up by Jocelyn Demoy, launched in March 2008, as well as a Polish edition.
A running gag in the forums is that the site is the original "WTF", as it doesn't provide even basic search capabilities.
History
The website was started on 17 May 2004, when Papadimoulis posted an entry entitled "Your Daily Cup of WTF" on his blog as a means of simply complaining about the quality of development at his then current employer. On his third such post, a reader of his blog suggested that he start a new website dedicated exclusively to such humorous "bad code" postings. A few days later, he registered TheDailyWTF.com domain name and began posting stories from readers of the site.
The content of the site kept evolving, and the body of articles was split into several columns. On 2 November 2006 Papadimoulis starting running code samples as articles entitled the "Code Snippets of the Day", "CodeSOD" for short. Originally edited by Tim Gallagher, the column was taken over by Derrick Pallas (now the sole editor of CodeSOD) as well as Devin Moore and Mike Nuss on 2 January 2007. On 12 February 2007 Jake Vinson started a new column, "Error'd", based on the old monthly series "Pop-Up Potpourri".
|
https://en.wikipedia.org/wiki/Paul%20Colinvaux | Paul Colinvaux (September 22, 1930 – February 28, 2016) was an ecologist and professor emeritus at Ohio State University.
Colinvaux was born in London, England. He attended University College School ("UCS") in London, where his activities included rowing in the Princess Elizabeth Challenge Cup at Henley Royal Regatta. After graduating from UCS, Colinvaux earned a commission in the Royal Artillery. He was stationed in Germany as part of the British occupation after World War II. Colinvaux achieved the rank of second lieutenant.
After leaving the army, Colinvaux matriculated at the University of Cambridge (Jesus College). After graduating, he emigrated to New Brunswick, Canada, where he was employed by a government soil survey. In New Brunswick, Colinvaux met his future wife, Llewellya Hillis of Windsor, Ontario. Hillis and Colinvaux married in British Columbia, before emigrating to the United States where Colinvaux earned his Ph.D. at Duke University. After completing post-doctoral studies at Yale University, Colinvaux and Hillis took up "his and her" appointments in the Department of Botany & Zoology at Ohio State University in 1964. They remained at the university until approximately 1990.
During his years at Ohio State University, Colinvaux won every teaching prize that could then be awarded for undergraduate teaching. He also played a role in ending the 1970 student riots at OSU (which is chronicled in Woody Hayes' memoir, You Win With People).
In 1991, Colinvaux and Hillis left Ohio State University to take positions with the Smithsonian Tropical Research Institute (STRI) in Panama. He left STRI later in the 1990s and, after settling in Woods Hole, Massachusetts, became affiliated with the University of Chicago Marine Biological Laboratory Ecosystems Center.
Life
Colinvaux was the author of several books, including Why Big Fierce Animals Are Rare: An Ecologist's Perspective (1978), The Fates of Nations: A Biological Theory of History (1980), and the textboo |
https://en.wikipedia.org/wiki/Neuroimaging | Neuroimaging is the use of quantitative (computational) techniques to study the structure and function of the central nervous system, developed as an objective way of scientifically studying the healthy human brain in a non-invasive manner. Increasingly it is also being used for quantitative research studies of brain disease and psychiatric illness. Neuroimaging is highly multidisciplinary involving neuroscience, computer science, psychology and statistics, and is not a medical specialty. Neuroimaging is sometimes confused with neuroradiology.
Neuroradiology is a medical specialty and uses non-statistical brain imaging in a clinical setting, practiced by radiologists who are medical practitioners. Neuroradiology primarily focuses on recognising brain lesions, such as vascular disease, strokes, tumors and inflammatory disease. In contrast to neuroimaging, neuroradiology is qualitative (based on subjective impressions and extensive clinical training) but sometimes uses basic quantitative methods. Functional brain imaging techniques, such as functional magnetic resonance imaging (fMRI), are common in neuroimaging but rarely used in neuroradiology. Neuroimaging falls into two broad categories:
Structural imaging, which is used to quantify brain structure using e,g, voxel based morphometry.
Functional imaging, which is used to study brain function, often using fMRI and other techniques such as PET and MEG (see below).
History
The first chapter of the history of neuroimaging traces back to the Italian neuroscientist Angelo Mosso who invented the 'human circulation balance', which could non-invasively measure the redistribution of blood during emotional and intellectual activity.
In 1918, the American neurosurgeon Walter Dandy introduced the technique of ventriculography. X-ray images of the ventricular system within the brain were obtained by injection of filtered air directly into one or both lateral ventricles of the brain. Dandy also observed that air i |
https://en.wikipedia.org/wiki/Distributed%20transmission%20system | In North American digital terrestrial television broadcasting, a distributed transmission system (DTS or DTx) is a form of single-frequency network in which a single broadcast signal is fed via microwave, landline, or communications satellite to multiple synchronised terrestrial radio transmitter sites. The signal is then simultaneously broadcast on the same frequency in different overlapping portions of the same coverage area, effectively combining many small transmitters to generate a broadcast area rivalling that of one large transmitter or to fill gaps in coverage due to terrain or localised obstacles.
History
While the idea of a single-frequency network of multiple transmitters broadcasting the same programming on the same channel from multiple transmitter sites is not a new concept, the ATSC digital television standard in use in North America was not designed for this mode of operation and was poorly adapted to these applications. The restrictive timing requirements and poor multipath interference handling of early ATSC implementations would have precluded multiple synchronous transmitters on the same frequency at the time of the first wide-scale commercial ATSC deployment in 1998; these restrictions eased somewhat as receiver design advanced in subsequent years. By 2004, technology existed to provide digital television receivers with the means to detect static (not mobile or changing) multipath interference (subject to certain timing constraints) and compensate for its effects on the digital signal.
Tests have been run by various individual broadcasters or broadcast groups, including the Metropolitan Television Alliance (MTVA, a consortium of New York city television stations). A series of initial tests involving four distributed transmission sites and over 100 test measurement sites in NYC and New Jersey were completed in June 2008, along with smaller-scale tests in New York in 2007. The New York market is uniquely problematic for multipath reception due |
https://en.wikipedia.org/wiki/Human%20subject%20research | Human subject research is systematic, scientific investigation that can be either interventional (a "trial") or observational (no "test article") and involves human beings as research subjects, commonly known as test subjects. Human subject research can be either medical (clinical) research or non-medical (e.g., social science) research. Systematic investigation incorporates both the collection and analysis of data in order to answer a specific question. Medical human subject research often involves analysis of biological specimens, epidemiological and behavioral studies and medical chart review studies. (A specific, and especially heavily regulated, type of medical human subject research is the "clinical trial", in which drugs, vaccines and medical devices are evaluated.) On the other hand, human subject research in the social sciences often involves surveys which consist of questions to a particular group of people. Survey methodology includes questionnaires, interviews, and focus groups.
Human subject research is used in various fields, including research into advanced biology, clinical medicine, nursing, psychology, sociology, political science, and anthropology. As research has become formalized, the academic community has developed formal definitions of "human subject research", largely in response to abuses of human subjects.
Human subjects
The United States Department of Health and Human Services (HHS) defines a human research subject as a living individual about whom a research investigator (whether a professional or a student) obtains data through 1) intervention or interaction with the individual, or 2) identifiable private information (). (Lim, 1990)
As defined by HHS regulations ():
Intervention – physical procedures by which data is gathered and the manipulation of the subject and/or their environment for research purposes.
Interaction – communication or interpersonal contact between investigator and subject.
Private Information – information a |
https://en.wikipedia.org/wiki/S-equivalence | S-equivalence is an equivalence relation on the families of semistable vector bundles on an algebraic curve.
Definition
Let X be a projective curve over an algebraically closed field k. A vector bundle on X can be considered as a locally free sheaf. Every semistable locally free E on X admits a Jordan-Hölder filtration with stable subquotients, i.e.
where are locally free sheaves on X and are stable. Although the Jordan-Hölder filtration is not unique, the subquotients are, which means that is unique up to isomorphism.
Two semistable locally free sheaves E and F on X are S-equivalent if gr E ≅ gr F.
Algebraic curves
Vector bundles
Equivalence (mathematics) |
https://en.wikipedia.org/wiki/Rencontres%20numbers | In combinatorial mathematics, the rencontres numbers are a triangular array of integers that enumerate permutations of the set { 1, ..., n } with specified numbers of fixed points: in other words, partial derangements. (Rencontre is French for encounter. By some accounts, the problem is named after a solitaire game.) For n ≥ 0 and 0 ≤ k ≤ n, the rencontres number Dn, k is the number of permutations of { 1, ..., n } that have exactly k fixed points.
For example, if seven presents are given to seven different people, but only two are destined to get the right present, there are D7, 2 = 924 ways this could happen. Another often cited example is that of a dance school with 7 couples, where, after tea-break the participants are told to randomly find a partner to continue, then once more there are D7, 2 = 924 possibilities that 2 previous couples meet again by chance.
Numerical values
Here is the beginning of this array :
Formulas
The numbers in the k = 0 column enumerate derangements. Thus
for non-negative n. It turns out that
where the ratio is rounded up for even n and rounded down for odd n. For n ≥ 1, this gives the nearest integer.
More generally, for any , we have
The proof is easy after one knows how to enumerate derangements: choose the k fixed points out of n; then choose the derangement of the other n − k points.
The numbers are generated by the power series ; accordingly,
an explicit formula for Dn, m can be derived as follows:
This immediately implies that
for n large, m fixed.
Probability distribution
The sum of the entries in each row for the table in "Numerical Values" is the total number of permutations of { 1, ..., n }, and is therefore n!. If one divides all the entries in the nth row by n!, one gets the probability distribution of the number of fixed points of a uniformly distributed random permutation of { 1, ..., n }. The probability that the number of fixed points is k is
For n ≥ 1, the expected number of fixed points is 1 |
https://en.wikipedia.org/wiki/Coincidence%20point | In mathematics, a coincidence point (or simply coincidence) of two functions is a point in their common domain having the same image.
Formally, given two functions
we say that a point x in X is a coincidence point of f and g if f(x) = g(x).
Coincidence theory (the study of coincidence points) is, in most settings, a generalization of fixed point theory, the study of points x with f(x) = x. Fixed point theory is the special case obtained from the above by letting X = Y and taking g to be the identity function.
Just as fixed point theory has its fixed-point theorems, there are theorems that guarantee the existence of coincidence points for pairs of functions. Notable among them, in the setting of manifolds, is the Lefschetz coincidence theorem, which is typically known only in its special case formulation for fixed points.
Coincidence points, like fixed points, are today studied using many tools from mathematical analysis and topology. An equaliser is a generalization of the coincidence set. |
https://en.wikipedia.org/wiki/Coherent%20%28operating%20system%29 | Coherent is a clone of the Unix operating system for IBM PC compatibles and other microcomputers, developed and sold by the now-defunct Mark Williams Company (MWC). Historically, the operating system was a proprietary product, but it became open source in 2015, released under the BSD-3-Clause license.
Development
Coherent was not Unix; the Mark Williams Company had no rights to either the Unix trademark or the AT&T/Bell Labs source code. In the early years of its existence, MWC received a visit from an AT&T delegation looking to determine whether MWC was infringing on AT&T Unix property. The delegation included Dennis Ritchie, who concluded that "it was very hard to believe that Coherent and its basic applications were not created without considerable study of the OS code and details of its applications." However, he also stated that:
Much of the operating system was written by alumni from the University of Waterloo: Tom Duff, Dave Conroy, Randall Howard, Johann George, and Trevor John Thompson. Significant contributions were also made by people such as Nigel Bree (from Auckland, New Zealand), the later author of Ghost.
Versions
Coherent was originally written for the PDP-11 range of minicomputers in 1980, then ported to various early 1980s microcomputer systems including IBM PC compatibles and machines based on the Zilog Z8000 and Motorola 68000. Initially sold to OEMs, starting 1983 it was available on the consumer market from MWC directly. At this point, Coherent 2.3 offered roughly the functionality of Version 7 Unix on PC hardware, including the nroff formatter but not the BSD extensions offered by competing Unix/clone vendors; compared to its competitors, it was a small system distributed on only seven double-sided floppy disks, costing only US$500 for a license.
BYTE in 1984 called Coherent a "highly compatible UNIX Version 7 lookalike". In 1985 it criticized the difficulty of installation, but stated that "as a UNIX clone, Coherent is amazingly complete |
https://en.wikipedia.org/wiki/Communications%20%26%20Information%20Services%20Corps | The Communications and Information Services Corps (CIS) () – formerly the Army Corps of Signals – is one of the combat support corps of the Irish Defence Forces, the military of Ireland. It is responsible for the installation, maintenance and operation of communications and information systems for the command, control and administration of the Defence Forces, and the facilitation of accurate, real-time sharing of intelligence between the Army, Naval Service and Air Corps branches at home and overseas.
The CIS Corps is headquartered at McKee Barracks, Dublin, and comes under the command of an officer of Colonel rank, known as the Director of CIS Corps.
Mission
Formerly the Army Corps of Signals, the Communications and Information Services Corps is responsible for the development and operation of Information Technology and Telecommunications systems in support of Defence Forces tasks. It is also responsible for coordinating all communications – radio and line – and information systems, communications research and updating of communications in line with modern developments and operational requirements. The CIS Corps is tasked with utilising networking and information technologies in order to dramatically increase Defence Force operational effectiveness through the provision of timely and accurate information to the appropriate commander, along with the real time efficient sharing of information and intelligence with the Army, Naval Service and Air Corps, as well as with multinational partners involved in international peacekeeping and other actors as required.
This role includes the development and maintenance of a secure nationwide Defence Forces Telecommunications Network (DFTN), which can support both protected voice and data services, and the provision and maintenance of encrypted military communications equipment for use by Defence Forces personnel at home and abroad. CIS Corps units are dispersed throughout the DF giving Communications and IT support to each |
https://en.wikipedia.org/wiki/Drift%20fence | A drift fence is any long, continuous fence used to control the movement of animals in a particular open range, or to collect animals for research.
Drift fences were used in the Texas Panhandle from 1882 to 1887 to control "cattle drift"—the winter migration of livestock to warmer territory. Long sections of barbed wire fence were built by ranchers to keep the cattle from moving to the southern part of the state. This fence was disastrous for the animals during the winter of 1886–1887. Deep snow covered the grasslands, and the fence prevented the herds from migrating to greener pastures. As a result, the cattle froze to death along the fences. Some 75 percent perished during the winter.
See also
Charles Goodnight
Fence Cutting Wars |
https://en.wikipedia.org/wiki/Alpha%20beta%20barrel | An alpha/beta barrel is a protein fold formed by units composed of a short α-helix followed by two anti-parallel β-strands, followed by an α-helix and a β-strand; the three β-strands form a β-sheet that runs parallel to the barrel and the α-helix is in the outside of the barrel but does not contact the α-helices of the other repeats like in TIM barrels.
The protein structures known for this fold come proteins from the eukaryotic and archaeal initiation factor 6 family, namely the Methanococcus jannaschii aIF6 and Saccharomyces cerevisiae eIF6, and from the eIF6 from Dictyostelium discoideum.
These alpha/beta barrels are commonly occurring motifs constructed from repetitions of the beta-alpha-beta loop motif. This alpha/beta barrel is a domain of pyruvate kinase enzyme. |
https://en.wikipedia.org/wiki/N-gram | n-gram is a series of n adjacent letters (including punctuation marks and blanks), syllables, or rarely whole words found in a language dataset; or adjacent phonemes extracted from a speech-recording dataset, or adjacent base pairs extracted from a genome. They are collected from a text or speech corpus. If Latin numerical prefixes are used, then n-gram of size 1 is called a "unigram", size 2 a "bigram" (or, less commonly, a "digram") etc. If, instead of the Latin ones, the English cardinal numbers are furtherly used, then they are called "four-gram", "five-gram", etc. Similarly, using Greek numerical prefixes such as "monomer", "dimer", "trimer", "tetramer", "pentamer", etc., or English cardinal numbers, "one-mer", "two-mer", "three-mer", etc. are used in computational biology, for polymers or oligomers of a known size, called k-mers. When the items are words, -grams may also be called shingles.
Examples
Figure 1 shows several example sequences and the corresponding 1-gram, 2-gram and 3-gram sequences.
Here are further examples; these are word-level 3-grams and 4-grams (and counts of the number of times they appeared) from the Google n-gram corpus.
3-grams
ceramics collectables collectibles (55)
ceramics collectables fine (130)
ceramics collected by (52)
ceramics collectible pottery (50)
ceramics collectibles cooking (45)
4-grams
serve as the incoming (92)
serve as the incubator (99)
serve as the independent (794)
serve as the index (223)
serve as the indication (72)
serve as the indicator (120) |
https://en.wikipedia.org/wiki/KBD%20algorithm | The KBD algorithm is a cluster update algorithm designed for the fully frustrated Ising model in two dimensions, or more generally any two dimensional spin glass with frustrated plaquettes arranged in a checkered pattern. It is discovered in 1990 by Daniel Kandel, Radel Ben-Av, and Eytan Domany, and generalized by P. D. Coddington and L. Han in 1994. It is the inspiration for cluster algorithms used in quantum monte carlo simulations.
Motivation
The SW algorithm is the first non-local algorithm designed for efficient simulation of ferromagnetic spin models. However, it is soon realized that the efficiency of the algorithm cannot be extended to frustrated systems, due to an overly large correlation length of the generated clusters with respect to the underlying spin system. The KBD algorithm is an attempt to extend the bond-formation rule to the plaquettes of the lattice, such that the generated clusters are informed by the frustration profile, resulting in them being smaller than the SW ones, thereby making the algorithm more efficient in comparison. However, at the current stage, it is not known whether this algorithm can be generalized for arbitrary spin glass models.
Algorithm
We begin by decomposing the square lattice down into plaquettes arranged in a checkered pattern (such that the plaquettes only overlap vertex-wise but not edge-wise). Since the spin model is fully-frustrated, each plaquette must contain exactly one or three negative interactions. If the plaquette contains three negative interactions, then no bonds can be formed. However, if the plaquette contains one negative interaction, then two parallel bonds can be formed (perpendicular to the negative edge) with probability , where is the inverse temperature of the spin model.
The bonds will then form clusters on the lattice, on which the spins can be collectively flipped (either with the SW rule or the Wolff rule ). It can be shown that the update satisfies detailed balance, meaning that correc |
https://en.wikipedia.org/wiki/Great%20blue%20turaco | The great blue turaco (Corythaeola cristata) is a bird species of the family Musophagidae. At in length, it is the largest species of turaco. It has predominantly grey-blue plumage with an upright blue-black crest around high. The male and female have similar plumage. It is widespread throughout the African tropical rainforest.
Taxonomy
French ornithologist Louis Vieillot described the great blue turaco as Musophaga cristata in 1816, before German ornithologist Ferdinand Heine placed it in its own genus in 1860.
The great blue turaco is the sole member of the subfamily Corythaeolinae within the turaco family. Its closest relatives are the go-away birds and plantain eaters of the genus Crinifer. The common ancestor of both diverged from the ancestor of all other turaco species.
"Great blue turaco" has been designated the official common name by the International Ornithologists' Union (IOC). It is also called blue plantain eater.
Description
Generally, the great blue turaco is in length with a mass of . The adult great blue turaco has predominantly gray-blue upperparts with an upright blue-black crest, white chin, yellow-green lower breast and yellow belly darkening to chestnut brown posteriorly. The undertail coverts are chestnut, and the undertail is black and yellowish. The yellow bill has an orange-red tip, the eyes are brown, and surrounded by a ring of black bare skin. The legs and feet are black with yellow soles. The sexes have similar plumage.
Distribution and habitat
The species ranges from Guinea in the west, east across the sub-Saharan nations to the Imatong Mountains in South Sudan; it also occurs in Uganda, Tanzania and western Kenya, south to the Democratic Republic of Congo and Angola. It inhabits rainforests and gallery forests. It has also adapted to areas cleared by humans and can thrive in these areas.
Behaviour
The great blue turaco is gregarious, with birds forming small troops of some six or seven individuals.
Feeding
The great blue t |
https://en.wikipedia.org/wiki/Gens%20%28behaviour%29 | In animal behaviour, a gens (pl. gentes) or host race is a host-specific lineage of a brood parasite species. Brood parasites, such as cuckoos, which use multiple host species to raise their chicks evolve different gentes, each one specific to its host species. This specialisation allows the parasites to lay eggs that mimic those of their hosts, which in turn reduces the chances of the eggs being rejected by the hosts, with about 5% of well-matched eggs compared to 72% of mismatched eggs rejected.
The exact mechanisms of the evolution and maintenance of gens is still a matter of some research. However, it is believed that in common cuckoos, gens-specific properties are sex-linked and lie on the W chromosome of the female. Male cuckoos, which, like all male birds, have no W chromosome, are able to mate with females of any gens, and thereby maintain the cuckoo as one species. This is not the case in other brood parasites, such as cowbirds, in which both the male and female imprint on their preferred host. This leads to speciation, such as the indigo bird, which is suggested by the fact they have a more recent evolutionary origin than their hosts. |
https://en.wikipedia.org/wiki/Dehn%E2%80%93Sommerville%20equations | In mathematics, the Dehn–Sommerville equations are a complete set of linear relations between the numbers of faces of different dimension of a simplicial polytope. For polytopes of dimension 4 and 5, they were found by Max Dehn in 1905. Their general form was established by Duncan Sommerville in 1927. The Dehn–Sommerville equations can be restated as a symmetry condition for the [[h-vector|h-vector]] of the simplicial polytope and this has become the standard formulation in recent combinatorics literature. By duality, analogous equations hold for simple polytopes.
Statement
Let P be a d-dimensional simplicial polytope. For i = 0, 1, ..., d − 1, let fi denote the number of i-dimensional faces of P. The sequence
is called the 'f-vector of the polytope P. Additionally, set
Then for any k = −1, 0, ..., d − 2, the following Dehn–Sommerville equation' holds:
When k = −1, it expresses the fact that Euler characteristic of a (d − 1)-dimensional simplicial sphere is equal to 1 + (−1)d − 1.
Dehn–Sommerville equations with different k are not independent. There are several ways to choose a maximal independent subset consisting of equations. If d is even then the equations with k = 0, 2, 4, ..., d − 2 are independent. Another independent set consists of the equations with k = −1, 1, 3, ..., d − 3. If d is odd then the equations with k = −1, 1, 3, ..., d − 2 form one independent set and the equations with k = −1, 0, 2, 4, ..., d − 3 form another.
Equivalent formulations
Sommerville found a different way to state these equations:
where 0 ≤ k ≤ (d−1). This can be further facilitated introducing the notion of h-vector of P. For k = 0, 1, ..., d, let
The sequence
is called the h-vector of P. The f-vector and the h-vector uniquely determine each other through the relation
Then the Dehn–Sommerville equations can be restated simply as
The equations with 0 ≤ k ≤ (d−1) are independent, and the others are manifestly equivalent to them.
Richard Stan |
https://en.wikipedia.org/wiki/Instant-on | In computing, instant-on is the ability to boot nearly instantly, allowing to go online or to use a specific application without waiting for a PC's traditional operating system to launch. Instant-on technology is today mostly used on laptops, netbooks, and nettops because the user can boot up one program, instead of waiting for the PC's operating system to boot. This allows a user to launch a single program, such as a movie-playing program or a web browser, without the need of the whole operating system. There still remain a few true instant-on machines such as the Atari ST, as described in the Booting article. These machines had complete Operating Systems resident in ROM similar to the way in which the BIOS function is conventionally provided on current computer architectures. The "instant-on" concept as used here results from loading an OS, such as a legacy system DOS, with a small hard drive footprint. Latency inherent to mechanical drive performance can also be eliminated by using Live USB or Live SD flash memory to load systems at electronic speeds which are orders of magnitude faster.
List of systems
Acer InstaBoot Netbook (based on Splashtop)
Acer RevoBoot Nettop (based on Splashtop)
Asus Express Gate motherboards, notebooks, Eee Box (nettop), and EeePCs (based on Splashtop)
Canonical product announced in early 2010
Dell Latitude ON, Latitude On Reader (based on Splashtop), Latitude On Flash (based on Splashtop)
Google ChromeOS
HP QuickWeb Probook notebook (based on Splashtop)
HP Instant On Solution Voodoo & Envy notebook (based on Splashtop)
HP Instant Web netbook (based on Splashtop)
Lenovo QuickStart (based on Splashtop)
LG SmartOn (based on Splashtop)
Mandriva InstantOn
MSI Winki
Palm Foleo
Phoenix HyperSpace
Sony Quick Web Access (based on Splashtop)
Splashtop Inc. Splashtop
Xandros Presto
Timeline
In October 2007, ASUS introduced an instant-on capability branded "Express Gate" on select motherboards, using DeviceVM's Splashtop software and dedicat |
https://en.wikipedia.org/wiki/Colva%20Roney-Dougal | Colva Mary Roney-Dougal is a British mathematician specializing in group theory and computational algebra. She is Professor of Pure Mathematics at the University of St Andrews, and the Director of the Centre for Interdisciplinary Research in Computational Algebra at St Andrews. She is also known for her popularization of mathematics on BBC radio shows, including appearances on In Our Time about the mathematics of Emmy Noether and Pierre-Simon Laplace and on The Infinite Monkey Cage about the nature of infinity and numbers in the real world.
Roney-Dougal completed her PhD at the University of London in 2001. Her dissertation, Permutation Groups with a Unique Non-diagonal Self-paired Orbital, was supervised by Peter Cameron.
With John Bray and Derek Holt, Roney-Dougal is the co-author of the book The Maximal Subgroups of the Low-Dimensional Finite Classical Groups (London Mathematical Society and Cambridge University Press, 2013).
In 2015 she was given the inaugural Cheryl E. Praeger Visiting Research Fellowship, funding her to visit the University of Western Australia. |
https://en.wikipedia.org/wiki/National%20Information%20Assurance%20Partnership | The National Information Assurance Partnership (NIAP) is a United States government initiative to meet the security testing needs of both information technology consumers and producers that is operated by the National Security Agency (NSA), and was originally a joint effort between NSA and the National Institute of Standards and Technology (NIST).
Purpose
The long-term goal of NIAP is to help increase the level of trust consumers have in their information systems and networks through the use of cost-effective security testing, evaluation, and validation programs. In meeting this goal, NIAP seeks to:
Promote the development and use of evaluated IT products and systems
Champion the development and use of national and international standards for IT security
Common Criteria
Foster research and development in IT security requirements definition, test methods, tools, techniques, and assurance metrics
Support a framework for international recognition and acceptance of IT security testing and evaluation results
Facilitate the development and growth of a commercial security testing industry within the U.S.
Services
Common Criteria Evaluation and Validation Scheme (CCEVS)
Product / System Configuration Guidance
Product and Protection Profile Evaluation
Consistency Instruction Manuals
NIAP Validation Body
The principal objective of the NIAP Validation Body is to ensure the provision of competent IT security evaluation and validation services for both government and industry. The Validation Body has the ultimate responsibility for the operation of the CCEVS in accordance with its policies and procedures, and where appropriate: interpret and amend those policies and procedures. The NSA is responsible for providing sufficient resources to the Validation Body so that it may carry out its responsibilities.
The Validation Body is led by a Director and Deputy Director selected by NSA management. The Director of the Validation Body reports to the NIAP Director for administrat |
https://en.wikipedia.org/wiki/Revolving%20rivers | Revolving rivers are a surprising, uncommon way of sand pile growth that can be found in a few sands around the world, but has been studied in detail only for one Cuban sand from a place called Santa Teresa (Pinar del Rio province).
Description
When pouring "revolving" sand on a flat surface from a fixed position, the growth of a conical pile does not occur by the common avalanche mechanism, where sand slides down the pile in a more or less random fashion. What happens in that a relatively thin "river" of flowing sand travels from the pouring point at the apex of the pile to its base, while the rest of the sand at the surface is static. In addition, the river "revolves" around the pile either in clockwise or counter-clockwise directions (looking from top) depending on the initial conditions. Actually the river constitutes the "cutting edge" of a layer of sand that deposits as a helix on the conical pile, and makes it grow.
For small sandpiles, rivers are continuous, but they become intermittent
for larger piles.
History and state of the art
The phenomenon was observed first by E. Altshuler at the University of Havana in 1995, but at the time he assumed that it was well known, and temporarily forgot about it. In 2000, being at the University of Houston, he told K. E. Bassler, who showed a vivid interest in the matter. Embarrassingly enough, Altshuler was unable to demonstrate it before Bassler using a random sand from Houston, so he had to send him a video from Cuba after his return to the island.
Once the existence of the strange phenomenon was confirmed for everyone, E. Altshuler and a number of collaborators performed a systematic study in Havana, which was then jointly published with Bassler.
Further work has been done to understand in more detail the
phenomenon, and it has been found in other sands from different parts of the world.
However, the connection between the physical, chemical (and possibly biological) properties of the grains in a specific sand |
https://en.wikipedia.org/wiki/Union%20for%20Ethical%20Biotrade | The Union for Ethical BioTrade (UEBT) is a nonprofit association that promotes the "Sourcing with Respect" of ingredients that come from biodiversity. Members commit to gradually ensuring that their sourcing practices promote the conservation of biodiversity, respect traditional knowledge and assure the equitable sharing of benefits all along the supply chain, following the Ethical BioTrade Standard. Members also commit to the UEBT verification system, which includes undergoing independent third party verification against the Ethical BioTrade Standard, developing a work-plan for gradual compliance for all natural, as well as the commitment to continuous improvement once compliance is achieved.
History
UEBT is a membership-based organisation that was created in May 2007 in Geneva, Switzerland. It was conceptualized in response to multiple developments. First of all, the Convention on Biological Diversity (CBD) acknowledged that additional efforts were needed to reach out to the private sector. The CBD recognized the strong link between business and biodiversity, as well as the dependency of industry on biodiversity and it highlighted the key role the private sector plays in sustainable use and the need for efforts and tools to engage it. In pursuit of the decisions that CBD parties had taken regarding private sector engagement and the use of standards in this, the idea of UEBT was conceived. The creation of the Union for Ethical BioTrade also responded to the need expressed by small and medium-sized enterprises (SMEs) in developing countries for ways to differentiate biodiversity-based products in the market. Finally, UEBT built upon efforts initiated by the BioTrade Initiative of the United Nations Conference on Trade and Development (UNCTAD), which was created to contribute to making biodiversity a strategy for sustainable development.
On 8 May 2007, a meeting of the founding members took place and the articles of association were approved. To support the effor |
https://en.wikipedia.org/wiki/Acoustic%20admittance | Acoustic admittance is the measure of the flow of acoustic energy. It is measured in cubic meters per second (), per pascal (). By nature, acoustic impedance is the reciprocal of acoustic admittance. Immittance is a concept which combines both acoustic admittance and acoustic impedance.
Acoustic admittance is widely used in bioacoustics where immittance is indispensable for its ability to assist with differential diagnosis of middle ear disease using tympanometry. Acoustic admittance also has applications in construction and engineering, and has been utilized to research and develop an open-cell polyurethane foam that had mean pore sizes of 0.01 - 0.08 cm and a fibrous structure. |
https://en.wikipedia.org/wiki/ZNF821 | Zinc Finger Protein 821, also known as ZNF821, is a protein encoded by the ZNF821 gene. This gene is located on the 16th chromosome and is expressed highly in the testes, moderately expressed in the brain and low expression in 23 other tissues. The protein encoded is 412 amino acids long with 2 Zinc Finger motifs (C2H2 type) and a 23 amino acid long STPR domain.
Gene
Locus
ZNF821 is located at 16q22.2 on the minus strand, it is composed of 35,657 bases spanning from base 71,893,583 to 71,929,239. ZNF821 has 8 exons and is located in the same neighborhood as 4 other genes, ATXNL1, IST1, PKD1L3, AP1G1.
Transcriptional Regulation
Transcription of ZNF821 is handled by the promoter GXP_9784938 which is 539 bases long and located from base 71,884,046 to 71,884,585. The promoter region begins 404 base pairs upstream of the beginning of transcription. Several transcription factors with scores greater than 0.9 are predicted to regulate ZNF821 expression.
Expression
ZNF821 is highly expressed in the testes, almost 2.5 times as much as in the brain, the next most highly expressed in tissue. Expression in the brain is primarily during fetal development, with lower levels of expression occurring in the cerebellum. There are low levels of expression in most other tissues.
mRNA
Variants and Isoforms
ZNF821 has 7 different transcript variants and 4 isoforms. Variant 1 Isoform 1 is the second longest and but most abundant of all the variants and isoforms. While variant 2 is longer, it contains one fewer exon. Variant 1, Isoform 1 is 1987 bases long with a 5' UTR 415 bases long and a 3' UTR 433 bases long.
Protein
Characteristics
The protein encoded by the ZNF821 gene is 412 amino acids long with a calculated molecular weight of ~ 47 kDa and a predicted isoelectric point of 6.14. Compared to the rest of the human proteome, there are decreased amounts of Isoleucine and Tyrosine residues as well as increased levels of Arginine residues.
Structure
ZNF821 protein contains |
https://en.wikipedia.org/wiki/115%20%28number%29 | 115 (one hundred [and] fifteen) is the natural number following 114 and preceding 116.
In mathematics
115 has a square sum of divisors:
There are 115 different rooted trees with exactly eight nodes, 115 inequivalent ways of placing six rooks on a 6 × 6 chess board in such a way that no two of the rooks attack each other, and 115 solutions to the stamp folding problem for a strip of seven stamps.
115 is also a heptagonal pyramidal number. The 115th Woodall number,
is a prime number.
115 is the sum of the first five heptagonal numbers.
See also
115 (disambiguation) |
https://en.wikipedia.org/wiki/Monotone%20dualization | In theoretical computer science, monotone dualization is a computational problem of constructing the dual of a monotone Boolean function. Equivalent problems can also be formulated as constructing the transversal hypergraph of a given hypergraph, of listing all minimal hitting sets of a family of sets, or of listing all minimal set covers of a family of sets. These problems can be solved in quasi-polynomial time in the combined size of its input and output, but whether they can be solved polynomial time is an open problem.
Definitions
A Boolean function takes as input an assignment of truth values to its arguments, and produces as output another truth value. It is monotone when changing an argument from false to true cannot change the output from true to false. Every monotone Boolean function can be expressed as a Boolean expression using only logical disjunction ("or") and logical conjunction ("and"), without using logical negation ("not"). Such an expression is called a monotone Boolean expression. Every monotone Boolean expression describes a monotone Boolean function.
There may be many different expressions for the same function. Among them are two special expressions, the conjunctive normal form and disjunctive normal form. For monotone functions these two special forms can also be restricted to be monotone:
The conjunctive normal form of a monotone function expresses the function as a conjunction ("and") of clauses, each of which is a disjunction ("or") of some of the variables. A clause may appear in the conjunctive normal form if it is true whenever the overall function is true; in this case it is called an implicate, because the truth of the function implies the truth of the clause. This expression may be made canonical by restricting it to use only prime implicates, the implicates that use a minimal set of variables. The conjunctive normal form using only prime implicates is called the prime CNF.
The disjunctive normal form of a monotone function express |
https://en.wikipedia.org/wiki/Luigi%20Chierchia | Luigi Chierchia (born 1957) is an Italian mathematician, specializing in nonlinear differential equations, mathematical physics, and dynamical systems (celestial mechanics and Hamiltonian systems).
Chierchia studied physics and mathematics at the Sapienza University of Rome with Laurea degree in 1981 with supervisor Giovanni Gallavotti. After a year of military service, Chierchia studied mathematics at the Courant Institute of New York University and received his PhD there in 1985. His doctoral dissertation Quasi-Periodic Schrödinger Operators in One Dimension, Absolutely Continuous Spectra, Bloch Waves and integrable Hamiltonian Systems was supervised by Henry P. McKean. As a postdoc, Chierchia studied at the University of Arizona, ETH Zurich and the École Polytechnique in Paris. Since 2002 he has been Professor of Mathematical Analysis at Roma Tre University.
With Fabio Pusateri and his doctoral student Gabriella Pinzari, he succeeded in extending the KAM theorem for the three-body problem to the n-body problem. In KAM theory, Chierchia addressed invariant tori in phase-space Hamiltonian systems and stability questions. He has also done research on Arnold diffusion, spectral theory of the quasiperiodic one-dimensional Schrödinger equation, and analogs of KAM theory in infinite-dimensional Hamiltonian systems and partial differential equations (almost periodic nonlinear wave equations).
He was an invited speaker (with Gabriella Pinzari) at the International Congress of Mathematicians in Seoul in 2014, and at the conference Dynamics, Equations and Applications in Kraków in 2019.
Selected publications |
https://en.wikipedia.org/wiki/Ethernet%20flow%20control | Ethernet flow control is a mechanism for temporarily stopping the transmission of data on Ethernet family computer networks. The goal of this mechanism is to avoid packet loss in the presence of network congestion.
The first flow control mechanism, the pause frame, was defined by the IEEE 802.3x standard. The follow-on priority-based flow control, as defined in the IEEE 802.1Qbb standard, provides a link-level flow control mechanism that can be controlled independently for each class of service (CoS), as defined by IEEE P802.1p and is applicable to data center bridging (DCB) networks, and to allow for prioritization of voice over IP (VoIP), video over IP, and database synchronization traffic over default data traffic and bulk file transfers.
Description
A sending station (computer or network switch) may be transmitting data faster than the other end of the link can accept it. Using flow control, the receiving station can signal the sender requesting suspension of transmissions until the receiver catches up. Flow control on Ethernet can be implemented at the data link layer.
The first flow control mechanism, the pause frame, was defined by the Institute of Electrical and Electronics Engineers (IEEE) task force that defined full duplex Ethernet link segments. The IEEE standard 802.3x was issued in 1997.
Pause frame
An overwhelmed network node can send a pause frame, which halts the transmission of the sender for a specified period of time. A media access control (MAC) frame (EtherType 0x8808) is used to carry the pause command, with the Control opcode set to 0x0001 (hexadecimal). Only stations configured for full-duplex operation may send pause frames. When a station wishes to pause the other end of a link, it sends a pause frame to either the unique 48-bit destination address of this link or to the 48-bit reserved multicast address of . The use of a well-known address makes it unnecessary for a station to discover and store the address of the station at the othe |
https://en.wikipedia.org/wiki/Projective%20connection | In differential geometry, a projective connection is a type of Cartan connection on a differentiable manifold.
The structure of a projective connection is modeled on the geometry of projective space, rather than the affine space corresponding to an affine connection. Much like affine connections, projective connections also define geodesics. However, these geodesics are not affinely parametrized. Rather they are projectively parametrized, meaning that their preferred class of parameterizations is acted upon by the group of fractional linear transformations.
Like an affine connection, projective connections have associated torsion and curvature.
Projective space as the model geometry
The first step in defining any Cartan connection is to consider the flat case: in which the connection corresponds to the Maurer-Cartan form on a homogeneous space.
In the projective setting, the underlying manifold of the homogeneous space is the projective space RPn which we shall represent by homogeneous coordinates . The symmetry group of is G = PSL(n+1,R). Let H be the isotropy group of the point . Thus, M = G/H presents as a homogeneous space.
Let be the Lie algebra of G, and that of H. Note that . As matrices relative to the homogeneous basis, consists of trace-free matrices:
.
And consists of all these matrices with . Relative to the matrix representation above, the Maurer-Cartan form of G is a system of 1-forms satisfying the structural equations (written using the Einstein summation convention):
Projective structures on manifolds
A projective structure is a linear geometry on a manifold in which two nearby points are connected by a line (i.e., an unparametrized geodesic) in a unique manner. Furthermore, an infinitesimal neighborhood of each point is equipped with a class of projective frames. According to Cartan (1924),
Une variété (ou espace) à connexion projective est une variété numérique qui, au voisinage immédiat de chaque point, présente tous les car |
https://en.wikipedia.org/wiki/Super%20FX | [[File:SuperFX GSU-2-SP1 chip.jpg|right|thumb|250px|Super FX 2 chip on Super Mario World 2: Yoshi's Island]]
The Super FX is a coprocessor on the Graphics Support Unit (GSU) added to select Super Nintendo Entertainment System (SNES) video game cartridges, primarily to facilitate advanced 2D and 3D graphics. The Super FX chip was designed by Argonaut Games, who also co-developed the 3D space rail shooter video game Star Fox with Nintendo to demonstrate the additional polygon rendering capabilities that the chip had introduced to the SNES.
History
The Super FX chip design team included engineers Ben Cheese, Rob Macaulay, and James Hakewill. While in development, the Super FX chip was codenamed "Super Mario FX" and "MARIO". "MARIO", a backronym for "Mathematical, Argonaut, Rotation, & Input/Output", is printed on the face of the final production chip.
Because of high manufacturing costs and increased development time, few Super FX based games were made compared to the rest of the SNES library. Due to these increased costs, Super FX games often retailed at a higher MSRP compared to other SNES games.
According to Argonaut Games founder Jez San, Argonaut had initially intended to develop the Super FX chip for the Nintendo Entertainment System. The team programmed an NES version of the first-person combat flight simulator Starglider, which Argonaut had developed for the Atari ST and other home computers a few years earlier, and showed it to Nintendo in 1990. The prototype impressed the company, but they suggested that they develop games for the then-unreleased Super Famicom due to the NES's hardware becoming outdated in light of newer systems such as the Sega Genesis/Mega Drive and the TurboGrafx-16/PC Engine. Shortly after the 1990 Consumer Electronics Show held in Chicago, Illinois, Argonaut ported the NES version of Starglider to the Super Famicom, a process which took roughly one week according to San.
Function
The Super FX chip is used to render 3D polygons and t |
https://en.wikipedia.org/wiki/Audio%20leveler | An audio leveler performs an audio process similar to compression, which is used to reduce the dynamic range of a signal, so that the quietest portion of the signal is loud enough to hear and the loudest portion is not too loud.
Levelers work especially well with vocals, as there are huge dynamic differences in the human voice and levelers work in such a way as to sound very natural, letting the character of the sound change with the different levels but still maintaining a predictable and usable dynamic range.
A leveler is different from a compressor in that the ratio and threshold are controlled with a single control.
External links
TLA-100 Tube Levelling Amplifier by Summit Audio
Signal processing |
https://en.wikipedia.org/wiki/Mir-542%20microRNA%20precursor%20family | In molecular biology mir-542 microRNA is a short RNA molecule. MicroRNAs function to regulate the expression levels of other genes by several mechanisms.
See also
MicroRNA |
https://en.wikipedia.org/wiki/Acidity%20regulator | Acidity regulators, or pH control agents, are food additives used to change or maintain pH (acidity or basicity). They can be organic or mineral acids, bases, neutralizing agents, or buffering agents. Typical agents include the following acids and their sodium salts: sorbic acid, acetic acid, benzoic acid, and propionic acid. Acidity regulators are indicated by their E number, such as E260 (acetic acid), or simply listed as "food acid".
Acidity regulators differ from acidulants, which are often acidic but are added to confer sour flavors. They are not intended to stabilize the food, although that can be a collateral benefit. Acidity regulators are also important for food safety, as incorrect pH can result in bacteria growth.
See also
Adipic acid
List of food additives
Sodium bicarbonate |
https://en.wikipedia.org/wiki/Kobon%20triangle%20problem | The Kobon triangle problem is an unsolved problem in combinatorial geometry first stated by Kobon Fujimura (1903-1983). The problem asks for the largest number N(k) of nonoverlapping triangles whose sides lie on an arrangement of k lines. Variations of the problem consider the projective plane rather than the Euclidean plane, and require that the triangles not be crossed by any other lines of the arrangement.
Known upper bounds
Saburo Tamura proved that the number of nonoverlapping triangles realizable by lines is at most . G. Clément and J. Bader proved more strongly that this bound cannot be achieved when is congruent to 0 or 2 (mod 6). The maximum number of triangles is therefore at most one less in these cases. The same bounds can be equivalently stated, without use of the floor function, as:
Solutions yielding this number of triangles are known when is 3, 4, 5, 6, 7, 8, 9, 13, 15 or 17. For k = 10, 11 and 12, the best solutions known reach a number of triangles one less than the upper bound.
Known constructions
Given an optimal solution with k0 > 3 lines, other Kobon triangle solution numbers can be found for all ki-values where
by using the procedure by D. Forge and J. L. Ramirez Alfonsin. For example, the solution for k0 = 5 leads to the maximal number of nonoverlapping triangles for k = 5, 9, 17, 33, 65, ....
Examples
See also
Roberts's triangle theorem, on the minimum number of triangles that lines can form |
https://en.wikipedia.org/wiki/Sourdough%20Sam | Sourdough Sam is a mascot for the NFL's San Francisco 49ers.
History
Before the introduction of Sourdough Sam, the 49ers' first mascot was a mule named Clementine that wore a red saddle blanket and appeared in the 1950s and 1960s.
A gold rush prospector–themed character first appeared in the 1970s. The character's design reflected the cover art of programs created by William Kay between 1946 and 1949—when the 49ers were a part of the All-America Football Conference—which depicted a bushy-mustached prospector with two pistols.
Sourdough Sam's persona later underwent a slight change from prospector to miner. As a miner, he depicted a large man with an oversized football helmet and plaid shirt matching that worn in the original William Kay cover art. Several elements of this version of Sourdough Sam, such as a bushy beard and suspenders, remained part of his image in later iterations. In 1985, this version of Sourdough Sam appeared in a cookbook titled 49er Fixens.
Another design change switched his helmet for a wide-brimmed ten-gallon hat with a chunk taken out of its brim and gave him a longer brown beard and larger, brown eyes.
Just prior to the 2006 NFL season, Sam's appearance was altered somewhat: He appeared as a clean-shaven gold panner with blue eyes and a hat without any imperfections.
Sourdough Sam returned for the 2011 season with a beard and blue eyes.
Outfit
Sourdough Sam typically wears a cardinal football jersey, despite the 49ers' current selection of team color being 49ers Red, and his jersey number is 49. He wears a white long-sleeved shirt underneath the jersey and sports light brown gloves as well as a gold handkerchief around his neck. He also wears a large, dark brown cowboy hat emblazoned with the logo for the 49ers and dark brown boots. His jeans are held up by suspenders, and in 2014 he was outfitted with a new pair of Levi's jeans after 60 years of wearing a non-branded pair, with promotional images of his entering Levi's Taylor Shop a |
https://en.wikipedia.org/wiki/Biogenic%20substance | A biogenic substance is a product made by or of life forms. While the term originally was specific to metabolite compounds that had toxic effects on other organisms, it has developed to encompass any constituents, secretions, and metabolites of plants or animals. In context of molecular biology, biogenic substances are referred to as biomolecules. They are generally isolated and measured through the use of chromatography and mass spectrometry techniques. Additionally, the transformation and exchange of biogenic substances can by modelled in the environment, particularly their transport in waterways.
The observation and measurement of biogenic substances is notably important in the fields of geology and biochemistry. A large proportion of isoprenoids and fatty acids in geological sediments are derived from plants and chlorophyll, and can be found in samples extending back to the Precambrian. These biogenic substances are capable of withstanding the diagenesis process in sediment, but may also be transformed into other materials. This makes them useful as biomarkers for geologists to verify the age, origin and degradation processes of different rocks.
Biogenic substances have been studied as part of marine biochemistry since the 1960s, which has involved investigating their production, transport, and transformation in the water, and how they may be used in industrial applications. A large fraction of biogenic compounds in the marine environment are produced by micro and macro algae, including cyanobacteria. Due to their antimicrobial properties they are currently the subject of research in both industrial projects, such as for anti-fouling paints, or in medicine.
History of discovery and classification
During a meeting of the New York Academy of Sciences' Section of Geology and Mineralogy in 1903, geologist Amadeus William Grabau proposed a new rock classification system in his paper 'Discussion of and Suggestions Regarding a New Classification of Rocks'. Within |
https://en.wikipedia.org/wiki/Radoslav%20Rochallyi | Radoslav Rochallyi (born 1 May 1980), Bardejov , Czechoslovakia is a Slovak writer, and poet living in the Malta, and Czech Republic.
Biography
Rochallyi was born in Bardejov, Czechoslovakia in a family with Lemko and Hungarian roots. He start reading even before started primary school. The first book he read was the book Black Ships by Maciej Słomczyński. Around his eight years, he came across Lermontov's poems. Rochallyi started writing poetry as a ten-year-old, and he published own works in magazines from the age of sixteen. The Author graduated in Management at the London International Graduate School and holds a certificate in Fine arts, which he received at the Pratt Institute. He also studied philosophy, and mathematics (linear algebra).
He is a member of Mensa.
Writing
Rochallyi is the author of fifteen books. In addition to Slovak and English, Rochallyi writes in Hungarian, Czech,,and German. He debuted with the collection of poetry Panoptikum: Haikai no renga (2004), written in Japanese haiku.
According to Jan Balaz, the poetry of Radoslav Rochally is characterized by the use of a free verse, which gives the author the necessary freedom and directness to retain the specific nature of the testimony without embellishments. His book Mythra Invictus has received a positive reception.
According to Lenka Vrebl, the perception of Radoslav Rochallyi is not playful, it is serious, direct and focused.
In the DNA-Canvases of Poetry collection he uses mathematical equations to express his poetry.
In addition to his book, poetic equations have also been published in many anthologies and journals. For example, in anthologies and journals published at Stanford University, California State University, Utah Tech University, Olivet College, or Las Positas College.
In the Punch collection, he uses poems based on mathematics, especially on mathematical equations. Both the texts and the equations are based on the author's need to divide the text into a semantically an |
https://en.wikipedia.org/wiki/Talari%20Networks | Talari Networks is a San Jose, CA-based manufacturer of networking equipment that allows businesses to combine private wide area networks (WANs) with less expensive broadband connections such as DSL or cable. It was founded in 2007 and launched its initial beta product in early 2008. The company was acquired by Oracle Corporation in 2018.
History
Talari Networks was founded in 2007 by Andy Gottlieb and John Dickey, former colleagues at Applied Micro. Gottlieb became the company’s first CEO, and Dickey became Vice President of Engineering. The company launched its initial beta product in early 2008. Mark Masur was then named CEO of Talari. In 2017 Dell veteran, Patrick Sweeney, was named CEO.
On November 15, 2018, Oracle Corporation announced that it had agreed to acquire Talari Networks. The transaction was expected to close by the end of 2018. |
https://en.wikipedia.org/wiki/Adiabatic%20process | In thermodynamics, an adiabatic process (Greek: adiábatos, "impassable") is a type of thermodynamic process that occurs without transferring heat or mass between the thermodynamic system and its environment. Unlike an isothermal process, an adiabatic process transfers energy to the surroundings only as work. As a key concept in thermodynamics, the adiabatic process supports the theory that explains the first law of thermodynamics.
Some chemical and physical processes occur too rapidly for energy to enter or leave the system as heat, allowing a convenient "adiabatic approximation". For example, the adiabatic flame temperature uses this approximation to calculate the upper limit of flame temperature by assuming combustion loses no heat to its surroundings.
In meteorology and oceanography, adiabatic expanding produces condensation of moisture or salinity, oversaturating the parcel. Therefore, the excess must be removed. There, the process becomes a pseudo-adiabatic process whereby the liquid water or salt that condenses is assumed to be removed upon formation by idealized instantaneous precipitation. The pseudoadiabatic process is only defined for expansion because a compressed parcel becomes warmer and remains undersaturated.
Description
A process without transfer of heat to or from a system, so that , is called adiabatic, and such a system is said to be adiabatically isolated. The simplifying assumption frequently made is that a process is adiabatic. For example, the compression of a gas within a cylinder of an engine is assumed to occur so rapidly that on the time scale of the compression process, little of the system's energy can be transferred out as heat to the surroundings. Even though the cylinders are not insulated and are quite conductive, that process is idealized to be adiabatic. The same can be said to be true for the expansion process of such a system.
The assumption of adiabatic isolation is useful and often combined with other such idealizations to |
https://en.wikipedia.org/wiki/ENEA%20AB | Enea AB is a global information technology company with its headquarters in Kista, Sweden that provides real-time operating systems and consulting services. Enea, which is an abbreviation of Engmans Elektronik Aktiebolag, also produces the OSE operating system.
History
Enea was founded 1968 by Rune Engman as Engmans Elektronik AB. Their first product was an operating system for a defence computer used by the Swedish Air Force. During the 1970s the firm developed compiler technology for the Simula programming language.
During the early days of the European Internet-like connections, Enea employee Björn Eriksen connected Sweden to EUnet using UUCP, and registered enea as the first Swedish domain in April 1983. The domain was later converted to the internet domain enea.se when the network was switched over to TCP and the Swedish top domain .se was created in 1986.
Products
OSE
The ENEA OSE real-time operating system first released in 1985.
The Enea multi core family of real-time operating systems was first released in 2009.
The Enea Operating System Embedded (OSE) is a family of real-time, microkernel, embedded operating system created by Bengt Eliasson for ENEA AB, which at the time was collaborating with Ericsson to develop a multi-core system using Assembly, C, and C++. Enea OSE Multicore Edition is based on the same microkernel architecture. The kernel design that combines the advantages of both traditional asymmetric multiprocessing (AMP) and symmetric multiprocessing (SMP). Enea OSE Multicore Edition offers both AMP and SMP processing in a hybrid architecture. OSE supports many processors, mainly 32-bit. These include the ColdFire, ARM, PowerPC, and MIPS based system on a chip (SoC) devices.
The Enea OSE family features three OSs: OSE (also named OSE Delta) for processors by ARM, PowerPC, and MIPS, OSEck for various DSP's, and OSE Epsilon for minimal devices, written in pure assembly (ARM, ColdFire, C166, M16C, 8051). OSE is a closed-source proprietari |
https://en.wikipedia.org/wiki/Mitochondrial%20unfolded%20protein%20response | The mitochondrial unfolded protein response (UPRmt) is a cellular stress response related to the mitochondria. The UPRmt results from unfolded or misfolded proteins in mitochondria beyond the capacity of chaperone proteins to handle them. The UPRmt can occur either in the mitochondrial matrix or in the mitochondrial inner membrane. In the UPRmt, the mitochondrion will either upregulate chaperone proteins or invoke proteases to degrade proteins that fail to fold properly. UPRmt causes the sirtuin SIRT3 to activate antioxidant enzymes and mitophagy.
Mitochondrial electron transport chain mutations that extend the life span of Caenorhabditis elegans (nematode worms) also activate the UPRmt. Activation of the UPRmt in nematode worms by increasing NAD+ by supplementation with nicotinamide or nicotinamide riboside has been shown to extend lifespan. Nicotinamide riboside supplementation in mice has also been shown to activate the UPRmt.
Cellular unfolded protein responses
A majority of cellular proteins are translated and folded in the cytosol with the help of molecular chaperones. Just as proteins must be folded to function in the cytosol, proteins in organelles like the endoplasmic reticulum (ER) and mitochondria also must be folded to function. Consequently, specific cellular mechanisms exist that aim to detect cellular stress (causing misfolded/unfolded proteins to accumulate), transduce the signal to the nucleus, and mediate the restoration of protein homeostasis (proteostasis). In the cytosol, the heat shock response (HSR) manages the unfolded proteins through heat shock factor 1 (HSF1). HSF-1 is a transcription factor that, upon increases in unfolded cytosolic proteins, will trimerize and enter the nucleus to upregulate the expression of heat shock proteins (HSPs) that will act as protein folding chaperones.
In organelles like the ER and mitochondria, the responses is slightly more complex. Both UPR mechanisms are conceptually similar in that they are activated |
https://en.wikipedia.org/wiki/S-knot | In loop quantum gravity, an s-knot is an equivalence class of spin networks under diffeomorphisms. In this formalism, s-knots represent the quantum states of the gravitational field.
External links
Living Reviews in Relativity: Loop Quantum Gravity: Diffeomorphism invariance
Loop quantum gravity |
https://en.wikipedia.org/wiki/Binary%20liquid | Binary liquid is a type of chemical combination, which creates a special reaction or feature as a result of mixing two liquid chemicals, that are normally inert or have no function by themselves. A number of chemical products are produced as a result of mixing two chemicals as a binary liquid, such as plastic foams and some explosives.
See also
Binary chemical weapon
Thermophoresis
Percus-Yevick equation |
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