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https://en.wikipedia.org/wiki/X-Wrt | X-Wrt is a set of packages and patches to provide a web interface for the Linux distribution OpenWrt. It is based on and has nothing to do with the X Window System. It allows web based management of an OpenWrt device. It was originally created as a package for OpenWrt White Russian. At present it can be found in the OpenWrt trunk as the webif package. Some newer features such as dual-band support may not be present. On 31 October 2013, the X-Wrt homepage moved to Google Code.
Features
X-Wrt is an extension of OpenWrt for the end-user.
OpenWrt, prior to release 8.09, had a minimal web-management console, whereas X-Wrt is supplied with an enhanced web-management console, , which has more than 40 control and status pages for a router. has pages that include graphical traffic and system status monitoring, and pages for the control and status of the network, wireless, and security. Controls are provided for data logging, booting, cron, NVRAM, file editing, Linux package management, SNMP, backup and restore, firmware upgrade, WAN, VLAN, Wi-Fi, WEP, WPA, WDS, MAC filtering, firewall, port forwarding, DHCP, Dnsmasq, hostnames, IP control, routing, UPnP, QoS, DynDNS, WoL, OpenVPN, PPTP, and hotspots. |
https://en.wikipedia.org/wiki/Plant%20evolutionary%20developmental%20biology | Evolutionary developmental biology (evo-devo) is the study of developmental programs and patterns from an evolutionary perspective. It seeks to understand the various influences shaping the form and nature of life on the planet. Evo-devo arose as a separate branch of science rather recently. An early sign of this occurred in 1999.
Most of the synthesis in evo-devo has been in the field of animal evolution, one reason being the presence of model systems like Drosophila melanogaster, C. elegans, zebrafish and Xenopus laevis. However, since 1980, a wealth of information on plant morphology, coupled with modern molecular techniques has helped shed light on the conserved and unique developmental patterns in the plant kingdom also.
Historical perspective
Before 1900
The origin of the term "morphology" is generally attributed to Johann Wolfgang von Goethe (1749–1832). He was of the opinion that there is an underlying fundamental organisation () in the diversity of flowering plants. In his book The Metamorphosis of Plants, he proposed that the enabled us to predict the forms of plants that had not yet been discovered. Goethe was the first to make the perceptive suggestion that flowers consist of modified leaves. He also entertained different complementary interpretations.
In the middle centuries, several basic foundations of our current understanding of plant morphology were laid down. Nehemiah Grew, Marcello Malpighi, Robert Hooke, Antonie van Leeuwenhoek, Wilhelm von Nageli were just some of the people who helped build knowledge on plant morphology at various levels of organisation. It was the taxonomical classification of Carl Linnaeus in the eighteenth century though, that generated a firm base for the knowledge to stand on and expand. The introduction of the concept of Darwinism in contemporary scientific discourse also had had an effect on the thinking on plant forms and their evolution.
Wilhelm Hofmeister, one of the most brilliant botanists of his times, was |
https://en.wikipedia.org/wiki/SecPAL | SecPAL is a declarative, logic-based, security policy language that has been developed to support the complex access control requirements of large scale distributed computing environments.
Common access control requirements
Here is a partial-list of some of the challenges that SecPAL addresses:
How does an organization establish a fine-grained trust relationship with another organization across organizational boundaries?
How does a user delegate a subset of a user’s rights (constrained delegation) to another user residing either in the same organization or in a different organization?
How can access control policy be authored and reviewed in a manner that is human readable - allowing auditors and non-technical people to understand such policies?
How does an organization support compliance regulations requiring that a system be able to demonstrate exactly why it was that a user was granted access to a resource?
How can policies be authored, composed and evaluated in a manner that is efficient, deterministic and tractable?
Architecture
The SecPAL Research homepage includes links to the following papers which describe the architecture of SecPAL at varying levels of abstraction.
SecPAL Formal Model ("Design and Semantics of a Decentralized Authorization Language") – Formal description of the abstract types, language semantics and evaluation rules that support deterministic evaluation in efficient time.
SecPAL Schema Specification – Specification describing a practical XML based implementation of the formal model targeted at supporting access control requirements of distributed applications
.NET Research Implementation of SecPAL – C# implementation, C# samples for common authz patterns, and comprehensive developer documentation and a getting started tutorial
Additional research
IEEE Grid 2007 - Fine Grained Access Control Using SecPAL
SecPAL for Privacy |
https://en.wikipedia.org/wiki/Gough%E2%80%93Joule%20effect | The Gough–Joule effect (a.k.a. Gow–Joule effect) is originally the tendency of elastomers to contract when heated if they are under tension. Elastomers that are not under tension do not see this effect. The term is also used more generally to refer to the dependence of the temperature of any solid on the mechanical deformation. This effect can be observed in nylon strings of classical guitars, whereby the string contracts as a result of heating. The effect is due to the decrease of entropy when long chain molecules are stretched.
If an elastic band is first stretched and then subjected to heating, it will shrink rather than expand. This effect was first observed by John Gough in 1802, and was investigated further by James Joule in the 1850s, when it then became known as the Gough–Joule effect.
Examples in Literature:
Popular Science magazine, January 1972: "A stretched piece of rubber contracts when heated. In doing so, it exerts a measurable increase in its pull. This surprising property of rubber was first observed by James Prescott Joule about a hundred years ago and is known as the Joule effect."
Rubber as an Engineering Material (book), by Khairi Nagdi: "The Joule effect is a phenomenon of practical importance that must be considered by machine designers. The simplest way of demonstrating this effect is to suspend a weight on a rubber band sufficient to elongate it at least 50%. When the stretched rubber band is warmed up by an infrared lamp, it does not elongate because of thermal expansion, as may be expected, but it retracts and lifts the weight."
The effect is important in O-ring seal design, where the seals can be mounted in a peripherally compressed state in hot applications to prolong life.
The effect is also relevant to rotary seals which can bind if the seal shrinks due to overheating. |
https://en.wikipedia.org/wiki/Macrogol | Macrogol, also known as polyethylene glycol (PEG), is used as a medication to treat constipation in children and adults. It is also used to empty the bowels before a colonoscopy. It is taken by mouth. Benefits usually occur within three days. Generally it is only recommended for up to two weeks. It is also used as an excipient.
Side effects may include increased bowel gas, abdominal pain, and nausea. Rare but serious side effects may include an abnormal heartbeat, seizures, and kidney problems. Use appears to be safe during pregnancy. It is classified as an osmotic laxative. It works by increasing the amount of water in the stool.
Macrogol came into use as a bowel prep in 1980 and was approved for medical use in the United States in 1999. It is available as a generic medication and over the counter. In 2020, it was the 226th most commonly prescribed medication in the United States, with more than 2million prescriptions. Typically it is formulated together with electrolytes.
Medical uses
Constipation
Macrogol 3350, often in combination with electrolytes, is used for short-term relief of constipation as well as for long-term use in constipation of various causes, including in multiple sclerosis and Parkinson's disease patients (an often-overlooked non-motor symptom) as well as constipation caused by pharmaceutical drugs such as opioids and anticholinergics. Whole bowel irrigation with macrogol is part of the bowel preparation before surgery or colonoscopy. Limited data also support its use for the treatment of fecal impaction.
In those with chronic constipation it works better than lactulose.
A 2007 comparison showed that people with constipation had a better response to macrogol than to tegaserod. Popular types include: macrogol 3350, macrogol 4000, and macrogol 6000. The number represents the average molecular mass. Combining different molecular masses provides some control over the consistency.
Excipient
Macrogol is used as an excipient in pharmaceutical pr |
https://en.wikipedia.org/wiki/Ethulose | Ethulose is a laxative. It is also known as ethylhydroxyethylcellulose.
As a food additive with INS number 467, ethulose is used as an emulsifier. |
https://en.wikipedia.org/wiki/ATC%20code%20V09 |
V09A Central nervous system
V09AA Technetium (99mTc) compounds
V09AA01 Technetium (99mTc) exametazime
V09AA02 Technetium (99mTc) bicisate
V09AB Iodine (123I) compounds
V09AB01 Iodine iofetamine (123I)
V09AB02 Iodine iolopride (123I)
V09AB03 Iodine ioflupane (123I)
V09AX Other central nervous system diagnostic radiopharmaceuticals
V09AX01 Indium (111In) pentetic acid
V09AX03 Iodine (124I) 2β-carbomethoxy-3β-(4-iodophenyl)-tropane
V09AX04 Flutemetamol (18F)
V09AX05 Florbetapir (18F)
V09AX06 Florbetaben (18F)
V09AX07 Flortaucipir (18F)
V09B Skeleton
V09BA Technetium (99mTc) compounds
V09BA01 Technetium (99mTc) oxidronic acid
V09BA02 Technetium (99mTc) medronic acid
V09BA03 Technetium (99mTc) pyrophosphate
V09BA04 Technetium (99mTc) butedronic acid
V09C Renal system
V09CA Technetium (99mTc) compounds
V09CA01 Technetium (99mTc) pentetic acid
V09CA02 Technetium (99mTc) succimer
V09CA03 Technetium (99mTc) mertiatide
V09CA04 Technetium (99mTc) gluceptate
V09CA05 Technetium (99mTc) gluconate
V09CA06 Technetium (99mTc) ethylenedicysteine
V09CX Other renal system diagnostic radiopharmaceuticals
V09CX01 Sodium iodohippurate (123I)
V09CX02 Sodium iodohippurate (131I)
V09CX03 Sodium iothalamate (125I)
V09CX04 Chromium (51Cr) edetate
V09D Hepatic and reticulo endothelial system
V09DA Technetium (99mTc) compounds
V09DA01 Technetium (99mTc) disofenin
V09DA02 Technetium (99mTc) etifenin
V09DA03 Technetium (99mTc) lidofenin
V09DA04 Technetium (99mTc) mebrofenin
V09DA05 Technetium (99mTc) galtifenin
V09DB Technetium (99mTc), particles and colloids
V09DB01 Technetium (99mTc) nanocolloid
V09DB02 Technetium (99mTc) microcolloid
V09DB03 Technetium (99mTc) millimicrospheres
V09DB04 Technetium (99mTc) tin colloid
V09DB05 Technetium (99mTc) sulfur colloid
V09DB06 Technetium (99mTc) rheniumsulfide colloid
V09DB07 Technetium (99mTc) phytate
V09DX Other hepatic and reticulo endothelial system diagnostic radiopharmaceuticals
V09DX01 Selenium (75Se) tauroselcholic acid
V09E Respirat |
https://en.wikipedia.org/wiki/Suxibuzone | Suxibuzone is an analgesic used for joint and muscular pain. It is a prodrug of the non-steroidal anti-inflammatory drug (NSAID) phenylbutazone, and is commonly used in horses. |
https://en.wikipedia.org/wiki/Operating%20System%20Projects | OSP, an Environment for Operating System Projects, is a teaching operating system designed to provide an environment for an introductory course in operating systems. By selectively omitting specific modules of the operating system and having the students re-implement the missing functionality, an instructor can generate projects that require students to understand fundamental operating system concepts.
The distribution includes the OSP project generator, which can be used to package a project and produce stubs (files that are empty except for required components, and that can be compiled) for the files that the students must implement. OSP includes a simulator that the student code runs on.
See also
Mobile operating system
Network operating system
Operating system |
https://en.wikipedia.org/wiki/Immunoconjugate | Immunoconjugates are antibodies conjugated (joined) to a second molecule, usually a toxin, radioisotope or label.
These conjugates are used in immunotherapy and to develop monoclonal antibody therapy as a targeted form of chemotherapy when they are often known as antibody-drug conjugates.
When the conjugates include a radioisotope see radioimmunotherapy.
When the conjugates include a toxin see immunotoxin. |
https://en.wikipedia.org/wiki/Automated%20quality%20control%20of%20meteorological%20observations | A meteorological observation at a given place can be inaccurate for a variety of reasons, such as a hardware defect. Quality control can help spot which meteorological observations are inaccurate.
One of the main automated quality control programs used today in the area of meteorological observations is the meteorological assimilation data ingest system (MADIS).
History
Weather observation quality control systems verify probability, history, and trends. One of the main and simplest forms of quality control is the check of probability. This check throws out impossible observations, such as the dew point being higher than the temperature or data outside acceptable ranges, such as temperatures over 200 degrees Fahrenheit. Another basic quality control check is to have the data compared to preset geographic extremes, perhaps combined with diurnal variations. However this only flags the data as uncertain because the station could be reporting correctly but there is no way to know. A better way is to correlate with previous observations as well as the other simple checks. This method uses one hour persistence to check the quality of the current observation. This method makes continuity of observations better since the system is able to make better judgments on whether the current observations are bad or not.
Current
Systems such as MADIS use a three-pronged approach to quality control. This approach is much better mainly because it has more information to compare the current observation to. The first part of the process is the limit check. As already described the program checks whether the observation is within predetermined limits that are set according to whether they can physically exist or not. The second part is the temporal check which compares the station to its closest surrounding stations. The third part is internal checking, which compares the observation to previous ones and sees whether it makes sense or not. It also takes into account present weath |
https://en.wikipedia.org/wiki/Stimulus%20control | In behavioral psychology (or applied behavior analysis), stimulus control is a phenomenon in operant conditioning (also called contingency management) that occurs when an organism behaves in one way in the presence of a given stimulus and another way in its absence. A stimulus that modifies behavior in this manner is either a discriminative stimulus (Sd) or stimulus delta (S-delta). Stimulus-based control of behavior occurs when the presence or absence of an Sd or S-delta controls the performance of a particular behavior. For example, the presence of a stop sign (S-delta) at a traffic intersection alerts the driver to stop driving and increases the probability that "braking" behavior will occur. Such behavior is said to be emitted because it does not force the behavior to occur since stimulus control is a direct result of historical reinforcement contingencies, as opposed to reflexive behavior that is said to be elicited through respondent conditioning.
Some theorists believe that all behavior is under some form of stimulus control. For example, in the analysis of B. F. Skinner, verbal behavior is a complicated assortment of behaviors with a variety of controlling stimuli.
Characteristics
The controlling effects of stimuli are seen in quite diverse situations and in many aspects of behavior. For example, a stimulus presented at one time may control responses emitted immediately or at a later time; two stimuli may control the same behavior; a single stimulus may trigger behavior A at one time and behavior B at another; a stimulus may control behavior only in the presence of another stimulus, and so on. These sorts of control are brought about by a variety of methods and they can explain many aspects of behavioral processes.
In simple, practical situations, for example if one were training a dog using operant conditioning, optimal stimulus control might be described as follows:
The behavior occurs immediately when the discriminative stimulus is given.
The behav |
https://en.wikipedia.org/wiki/CG%20suppression | CG suppression is a term for the phenomenon that CG dinucleotides are very uncommon in most portions of vertebrate genomes.
In adult somatic tissues, cytosine residues may be methylated, and this occurs almost exclusively within a symmetric CpG context. Methylated C residues spontaneously deaminate to form T residues; hence CpG dinucleotides steadily mutate to TpG dinucleotides, which gives rise to the under-representation of CpG dinucleotides in the human genome (they occur at only 21% of the expected frequency). (On the other hand, spontaneous deamination of unmethylated C residues gives rise to U residues, a mutation that is quickly recognized and repaired by the cell).
In human and mouse, CGs are the least frequent dinucleotide, making up less than 1% of all dinucleotides. GCs are the second most infrequent, making up more than 4% of all dinucleotides, so CGs are more than fourfold less frequent than all other dinucleotides.
See also
CpG island |
https://en.wikipedia.org/wiki/Tropical%20Eastern%20Pacific | The Tropical Eastern Pacific is one of the twelve marine realms that cover the coastal waters and continental shelves of the world's oceans. The Tropical Eastern Pacific extends along the Pacific Coast of the Americas, from the southern tip of the Baja California Peninsula in the north to northern Peru in the south. It is bounded on the north by the Temperate Northern Pacific realm, and on the south by the Temperate South America realm.
It includes a number of oceanic islands and oceanic island groups like the Galápagos Islands, Revillagigedo Islands, Cocos Island, and Clipperton Island. Clipperton has been labelled as a meeting point between the Oceanian realm and the Tropical Eastern Pacific realm. The Galápagos Islands are also believed to have much higher percentages of Indo-West Pacific species in their marine faunas when compared to the continental American coasts. A 2018 study revealed interconnectivity of species between the Line Islands, Hawaii and Clipperton, as well as interconnectivity between the Galápagos Islands and Marquesas Islands in French Polynesia. The study identified the Northern Galápagos Islands as a "critical stepping-stone connecting the Central Pacific and Eastern Pacific."
The WWF and Nature Conservancy divide the Tropical Eastern Pacific realm into two marine provinces, Tropical East Pacific and Galápagos, which are further subdivided into marine ecoregions.
Ecoregions
Tropical East Pacific Marine Province
Revillagigedos
Clipperton
Mexican Tropical Pacific
Chiapas–Nicaragua
Nicoya
Cocos Island
Panama Bight
Guayaquil
Galápagos Marine Province
Northern Galápagos Islands
Eastern Galápagos Islands
Western Galápagos Islands |
https://en.wikipedia.org/wiki/Extracellular%20polymeric%20substance | Extracellular polymeric substances (EPSs) are natural polymers of high molecular weight secreted by microorganisms into their environment. EPSs establish the functional and structural integrity of biofilms, and are considered the fundamental component that determines the physicochemical properties of a biofilm. EPS in the matrix of biofilms provides compositional support and protection of microbial communities from the harsh environments. Components of EPS can be of different classes of polysaccharides, lipids, nucleic acids, proteins, lipopolysaccharides, and minerals.
Components
EPSs are mostly composed of polysaccharides (exopolysaccharides) and proteins, but include other macromolecules such as DNA, lipids and humic substances. EPSs are the construction material of bacterial settlements and either remain attached to the cell's outer surface, or are secreted into its growth medium. These compounds are important in biofilm formation and cells' attachment to surfaces. EPSs constitute 50% to 90% of a biofilm's total organic matter.
Exopolysaccharides (also sometimes abbreviated EPSs; EPS sugars thereafter) are the sugar-based parts of EPS. Microorganisms synthesize a wide spectrum of multifunctional polysaccharides including intracellular polysaccharides, structural polysaccharides and extracellular polysaccharides or exopolysaccharides. Exopolysaccharides generally consist of monosaccharides and some non-carbohydrate substituents (such as acetate, pyruvate, succinate, and phosphate). Owing to the wide diversity in composition, exopolysaccharides have found diverse applications in various food and pharmaceutical industries. Many microbial EPS sugars provide properties that are almost identical to the gums currently in use. With innovative approaches, efforts are underway to supersede the traditionally used plant and algal gums by their microbial counterparts. Moreover, considerable progress has been made in discovering and developing new microbial EPS sugars tha |
https://en.wikipedia.org/wiki/Transmission%20delay | In a network based on packet switching, transmission delay (or store-and-forward delay, also known as packetization delay or serialization delay) is the amount of time required to push all the packet's bits into the wire. In other words, this is the delay caused by the data-rate of the link.
Transmission delay is a function of the packet's length and has nothing to do with the distance between the two nodes. This delay is proportional to the packet's length in bits,
It is given by the following formula:
seconds
where
is the transmission delay in seconds
N is the number of bits, and
R is the rate of transmission (say in bits per second)
Most packet switched networks use store-and-forward transmission at the input of the link. A switch using store-and-forward transmission will receive (save) the entire packet to the buffer and check it for CRC errors or other problems before sending the first bit of the packet into the outbound link. Thus, store-and-forward packet switches introduce a store-and-forward delay at the input to each link along the packet's route.
See also
End-to-end delay
Processing delay
Queuing delay
Propagation delay
Network delay |
https://en.wikipedia.org/wiki/Eigendecomposition%20of%20a%20matrix | In linear algebra, eigendecomposition is the factorization of a matrix into a canonical form, whereby the matrix is represented in terms of its eigenvalues and eigenvectors. Only diagonalizable matrices can be factorized in this way. When the matrix being factorized is a normal or real symmetric matrix, the decomposition is called "spectral decomposition", derived from the spectral theorem.
Fundamental theory of matrix eigenvectors and eigenvalues
A (nonzero) vector of dimension is an eigenvector of a square matrix if it satisfies a linear equation of the form
for some scalar . Then is called the eigenvalue corresponding to . Geometrically speaking, the eigenvectors of are the vectors that merely elongates or shrinks, and the amount that they elongate/shrink by is the eigenvalue. The above equation is called the eigenvalue equation or the eigenvalue problem.
This yields an equation for the eigenvalues
We call the characteristic polynomial, and the equation, called the characteristic equation, is an th order polynomial equation in the unknown . This equation will have distinct solutions, where . The set of solutions, that is, the eigenvalues, is called the spectrum of .
If the field of scalars is algebraically closed, then we can factor as
The integer is termed the algebraic multiplicity of eigenvalue . The algebraic multiplicities sum to :
For each eigenvalue , we have a specific eigenvalue equation
There will be linearly independent solutions to each eigenvalue equation. The linear combinations of the solutions (except the one which gives the zero vector) are the eigenvectors associated with the eigenvalue . The integer is termed the geometric multiplicity of . It is important to keep in mind that the algebraic multiplicity and geometric multiplicity may or may not be equal, but we always have . The simplest case is of course when . The total number of linearly independent eigenvectors, , can be calculated by summing the geometric m |
https://en.wikipedia.org/wiki/Tunnel%20finisher | A tunnel finisher is a machine that removes wrinkles from garments and is often used in the textile industry. As with other industrial pressing equipment, this machine is employed to improve the quality and look of a textile product. It has a chamber called a "tunnel" and includes a conveyor fed unit through which the garments are steamed and dried. The machine also features hook systems; air curtain entrance to eliminate moisture or condensation; cotton care and roller units; exhaust steam, and a preconditioning module.
Process
Most garments are shipped by sea freight from the country of production. They get very wrinkled because of the box packing being used. In the receiving country, they are unpacked and put on a clothes hanger. Those hangers are sent via automated transport through the tunnel with a speed up to 3,000 garments per hour. These garments are then sent to a room to be steamed and dried.
The machine processes each garment through several stages. First, the garment passes through a steam chamber to make the fabric moldable. Then wrinkles are removed by a strong hot air flow alongside the garments. Finally, the garment is dried by cooler air before it leaves the tunnel finisher. In the case of garments, smaller areas such as collars require further pressing using other equipment such as steam iron for a better finish.
The tunnel finisher is also used in laundries and dry cleaners to remove wrinkles from garments after washing or dry cleaning.
Classifications
Tunnel finishers can be grouped into two different classifications, "wide body" or "narrow body." "Wide body" machines are designed for high production finishing of blended garments wet-to-dry, damp-to-dry and or dry-to-dry. "Narrow body" machines are designed for shoulder-to-shoulder processing and are best suited for the dry-to-dry finishing of garments. However; they are capable of damp-to-dry finishing at slower production speeds. These units are ideal for dry cleaners, hotel laundrie |
https://en.wikipedia.org/wiki/Seven-segment%20display%20character%20representations | The topic of seven-segment display character representations revolves around the various shapes of numerical digits, letters, and punctuation devisable on seven-segment displays. Such representation of characters is not standardized by any relevant entity (e.g. ISO, IEEE or IEC). Unicode provides encoding codepoint for segmented digits in Unicode 13.0 in Symbols for Legacy Computing block.
Digit
Two basic conventions are in common use for some Arabic numerals: display segment A is optional for digit 6 (/), segment F for 7 (/), and segment D for 9 (/). Although EF () could also be used to represent digit 1, this seems to be rarely done if ever. CDEG () is occasionally encountered on older calculators to represent 0.
In Unicode 13.0, 10 codepoints had been given for segmented digits 0–9 in the Symbols for Legacy Computing block:
Alphabet
In addition to the ten digits, seven-segment displays can be used to show most letters of the Latin, Cyrillic and Greek alphabets including punctuation.
One such special case is the display of the letters A–F when denoting the hexadecimal values (digits) 10–15. These are needed on some scientific calculators, and are used with some testing displays on electronic equipment. Although there is no official standard, today most devices displaying hex digits use the unique forms shown to the right: uppercase A, lowercase b, uppercase C, lowercase d, uppercase E and F. To avoid ambiguity between the digit 6 and the letter b the digit 6 is displayed with segment A lit.
However, this modern scheme was not always followed in the past, and various other schemes could be found as well:
The Texas Instruments seven-segment display decoder chips 7446/7447/7448/7449 and 74246/74247/74248/74249 and the Siemens FLH551-7448/555-8448 chips used truncated versions of "2", "3", "4", "5" and "6" for digits A–G. Digit F (1111 binary) was blank.
Soviet programmable calculators like the Б3-34 instead used the symbols "−", "L", "C", "Г", "E", and " " |
https://en.wikipedia.org/wiki/MPLAB | MPLAB is a proprietary freeware integrated development environment for the development of embedded applications on PIC and dsPIC microcontrollers, and is developed by Microchip Technology.
MPLAB X is the latest edition of MPLAB, and is developed on the NetBeans platform. MPLAB and MPLAB X support project management, code editing, debugging and programming of Microchip 8-bit PIC and AVR (including ATMEGA) microcontrollers, 16-bit PIC24 and dsPIC microcontrollers, as well as 32-bit SAM (ARM) and PIC32 (MIPS) microcontrollers.
MPLAB is designed to work with MPLAB-certified devices such as the MPLAB ICD 3 and MPLAB REAL ICE, for programming and debugging PIC microcontrollers using a personal computer. PICKit programmers are also supported by MPLAB.
MPLAB X supports automatic code generation with the MPLAB Code Configurator and the MPLAB Harmony Configurator plugins.
MPLAB X
MPLAB X is the latest version of the MPLAB IDE built by Microchip Technology, and is based on the open-source NetBeans platform. MPLAB X supports editing, debugging and programming of Microchip 8-bit, 16-bit and 32-bit PIC microcontrollers.
MPLAB X is the first version of the IDE to include cross-platform support for macOS and Linux operating systems, in addition to Microsoft Windows.
MPLAB X supports the following compilers:
MPLAB XC8 — C compiler for 8-bit PIC and AVR devices
MPLAB XC16 — C compiler for 16-bit PIC devices
MPLAB XC32 — C/C++ compiler for 32-bit MIPS-based PIC32 and ARM-based SAM devices
HI-TECH C — C compiler for 8-bit PIC devices (discontinued)
SDCC — open-source C compiler
MPLAB 8.x
MPLAB 8.x is the last version of the legacy MPLAB IDE technology, custom built by Microchip Technology in Microsoft Visual C++. MPLAB supports project management, editing, debugging and programming of Microchip 8-bit, 16-bit and 32-bit PIC microcontrollers. MPLAB only works on Microsoft Windows. MPLAB is still available from Microchip's archives, but is not recommended for new projects.
MP |
https://en.wikipedia.org/wiki/Pliohippus | Pliohippus (Greek (, "more") and (, "horse")) is an extinct genus of Equidae, the "horse family". Pliohippus arose in the middle Miocene, around 15 million years ago. The long and slim limbs of Pliohippus reveal a quick-footed steppe animal. While some specimens have one toe per leg, others have three (the main toe and two non-functional side toes).
Until recently, because of its many anatomical similarities, Pliohippus was believed to be the ancestor of the present-day horse and its relatives in Equus. Although Pliohippus clearly is an equid and thus related to Equus, its skull had deep facial fossae, a feature not found in any member of Equus. Additionally, its teeth were strongly curved, unlike the very straight teeth of modern horses. Consequently, it is unlikely to be the ancestor of the modern horse; instead, it is likely to be the ancestor of Astrohippus. Pliohippus stood approximately 1.25 metres, similar to the modern horse. Also like the modern horse, Pliohippus was a grazer that fed on steppe grasses of the North American plains it inhabited.
Fossils of Pliohippus have been found at many late Miocene localities in Colorado, the Great Plains (Nebraska, including Ashfall Fossil Beds and the Dakotas) and also Canada. Pliohippus has been found beside Neohipparion. |
https://en.wikipedia.org/wiki/Impulse%20excitation%20technique | The impulse excitation technique (IET) is a non-destructive material characterization technique to determine the elastic properties and internal friction of a material of interest. It measures the resonant frequencies in order to calculate the Young's modulus, shear modulus, Poisson's ratio and internal friction of predefined shapes like rectangular bars, cylindrical rods and disc shaped samples. The measurements can be performed at room temperature or at elevated temperatures (up to 1700 °C) under different atmospheres.
The measurement principle is based on tapping the sample with a small projectile and recording the induced vibration signal with a piezoelectric sensor, microphone, laser vibrometer or accelerometer. To optimize the results a microphone or a laser vibrometer can be used as there is no contact between the test-piece and the sensor. Laser vibrometers are preferred to measure signals in vacuum. Afterwards, the acquired vibration signal in the time domain is converted to the frequency domain by a fast Fourier transformation. Dedicated software will determine the resonant frequency with high accuracy to calculate the elastic properties based on the classical beam theory.
Elastic properties
Different resonant frequencies can be excited dependent on the position of the support wires, the mechanical impulse and the microphone. The two most important resonant frequencies are the flexural which is controlled by the Young's modulus of the sample and the torsional which is controlled by the shear modulus for isotropic materials.
For predefined shapes like rectangular bars, discs, rods and grinding wheels, dedicated software calculates the sample's elastic properties using the sample dimensions, weight and resonant frequency (ASTM E1876-15).
Flexure mode
The first figure gives an example of a test-piece vibrating in the flexure
mode. This induced vibration is also referred as the out-of-plane vibration mode. The in-plane vibration will be excited by turning |
https://en.wikipedia.org/wiki/Supervisor%20Call%20instruction | This article covers the specific instruction on the IBM System/360 and successor mainframe computers, and compatible machines. For the general concept of an instruction for issuing calls to an operating system, see System call.
A Supervisor Call instruction (SVC) is a hardware instruction used by the System/360 family of IBM mainframe computers up to contemporary zSeries, the Amdahl 470V/5, 470V/6, 470V/7, 470V/8, 580, 5880, 5990M, and 5990A, and others; Univac 90/60, 90/70 and 90/80, and possibly others; the Fujitsu M180 (UP) and M200 (MP), and others; and is also used in the Hercules open source mainframe emulation software. It causes an interrupt to request a service from the operating system. The system routine providing the service is called an SVC routine. SVC is a system call.
Rationale
IBM mainframes in the System/360 and successor families operate in one of two states: problem state or supervisor state and in one of sixteen storage access keys (0 to 15). In problem state, a large set of general purpose non-privileged instructions are available to a user program. In supervisor state, system programs are additionally able to use a small set of privileged instructions which are generally intended for supervisory functions. These functions may affect other users, other processors, or the entire computer system. In storage key 0 a program is able to access all addressable storage, otherwise it is limited to storage areas with a matching key.
A program is only allowed to access specific supervisory functions after thorough authorization checking by the operating system: DEBCHK (SVC 117), TESTAUTH (SVC 119), and possibly additional tests. Programs which fail any of these tests are ABENDed, that is abnormally terminated and immediately cease processing. Some of these tests were not available in OS/360, but were added in OS/VS1, SVS or MVS/370, but all were available in MVS/370 or subsequent releases, and are still available to this day.
In OS/VS1, OS/VS2 (SVS) |
https://en.wikipedia.org/wiki/Physical%20unclonable%20function | A physical unclonable function (sometimes also called physically-unclonable function, which refers to a weaker security metric than a physical unclonable function), or PUF, is a physical object that for a given input and conditions (challenge), provides a physically defined "digital fingerprint" output (response) that serves as a unique identifier, most often for a semiconductor device such as a microprocessor. PUFs are often based on unique physical variations occurring naturally during semiconductor manufacturing. A PUF is a physical entity embodied in a physical structure. PUFs are implemented in integrated circuits, including FPGAs, and can be used in applications with high-security requirements, more specifically cryptography, Internet of Things (IOT) devices and privacy protection.
History
Early references about systems that exploit the physical properties of disordered systems for authentication purposes date back to Bauder in 1983 and Simmons in 1984. Naccache and Frémanteau provided an authentication scheme in 1992 for memory cards. The terms POWF (physical one-way function) and PUF (physical unclonable function) were coined in 2001 and 2002, the latter publication describes the first integrated PUF where, unlike PUFs based on optics, the measurement circuitry and the PUF are integrated onto the same electrical circuit (and fabricated on silicon).
Starting in 2010, PUF gained attention in the smartcard market as a promising way to provide "silicon fingerprints", creating cryptographic keys that are unique to individual smartcards.
PUFs are now established as a secure alternative to battery-backed storage of secret keys in commercial FPGAs, such as the Xilinx Zynq Ultrascale+, and Altera Stratix 10.
Concept
PUFs depend on the uniqueness of their physical microstructure. This microstructure depends on random physical factors introduced during manufacturing. These factors are unpredictable and uncontrollable, which makes it virtually impossible to duplic |
https://en.wikipedia.org/wiki/Conditional%20short-circuit%20current | Conditional short-circuit current is the value of the alternating current component of a prospective current, which a switch without integral short-circuit protection, but protected by a suitable short circuit protective device (SCPD) in series, can withstand for the operating time of the current under specified test conditions. It may be understood to be the RMS value of the maximum permissible current over a specified time interval (t0,t1) and operating conditions.
The IEC definition is critiqued to be open to interpretation. |
https://en.wikipedia.org/wiki/Journal%20of%20Geophysics%20and%20Engineering | The Journal of Geophysics and Engineering is a peer-reviewed scientific journal covering research and developments in geophysics and related areas of engineering. Although the journal has a predominantly applied science and engineering focus, it also publishes contributions in all Earth-physics disciplines from global geophysics to applied and engineering geophysics. The editors-in-chief are Yanghua Wang (Imperial College London) and Qinyong Yang (Sinopec Geophysical Research Institute).
Abstracting and indexing
The Journal of Geophysics and Engineering is abstracted and indexed in Science Citation Index Expanded, Current Contents/Engineering, Computing and Technology, Current Contents/Physical, Chemical and Earth Sciences, Inspec, Scopus, Astrophysics Data System, and GEOBASE. According to the Journal Citation Reports, the journal has a 2017 impact factor of 1.411. |
https://en.wikipedia.org/wiki/Never%20event | A never event is the "kind of mistake (medical error) that should never happen" in the field of medical treatment.
According to the Leapfrog Group never events are defined as "adverse events that are serious, largely preventable, and of concern to both the public and health care providers for the purpose of public accountability."
A 2012 study reported there may be as many as 1,500 instances of one never event, a retained foreign object, per year in the United States. The same study suggests an estimated total of surgical mistakes at just over 4,000 per year in the United States, but these statistics are extrapolations from small samples rather than actual event counts.
United States
A list of events was compiled by the National Quality Forum and updated in 2012.
The NQF’s report recommends a national state-based event reporting system to improve the quality of patient care.
Artificial insemination with the wrong donor sperm or donor egg
Unintended retention of a foreign body in a patient after surgery or other procedure
Patient death or serious disability associated with patient elopement (disappearance)
Patient death or serious disability associated with a medication error (e.g., errors involving the wrong drug, dose, patient, time, rate, preparation or route of administration)
Patient death or serious disability associated with a hemolytic reaction due to the administration of ABO/HLA-incompatible blood or blood products
Patient death or serious disability associated with an electric shock or elective cardioversion while being cared for in a healthcare facility
Patient death or serious disability associated with a fall while being cared for in a healthcare facility
Surgery performed on the wrong body part
Surgery performed on the wrong patient
Wrong surgical procedure performed on a patient
Intraoperative or immediately postoperative death in an ASA Class I patient
Patient death or serious disability associated with the use of contaminated drugs, |
https://en.wikipedia.org/wiki/Surface%20conductivity | Surface conductivity is an additional conductivity of an electrolyte in the vicinity of the charged interfaces. Surface and volume conductivity of liquids correspond to the electrically driven motion of ions in an electric field. A layer of counter ions of the opposite polarity to the surface charge exists close to the interface. It is formed due to attraction of counter-ions by the surface charges. This layer of higher ionic concentration is a part of the interfacial double layer. The concentration of the ions in this layer is higher as compared to the ionic strength of the liquid bulk. This leads to the higher electric conductivity of this layer.
Smoluchowski was the first to recognize the importance of surface conductivity at the beginning of the 20th century.
There is a detailed description of surface conductivity by Lyklema in "Fundamentals of Interface and Colloid Science"
The Double Layer (DL) has two regions, according to the well established Gouy-Chapman-Stern model. The upper level, which is in contact with the bulk liquid is the diffuse layer. The inner layer that is in contact with interface is the Stern layer.
It is possible that the lateral motion of ions in both parts of the DL contributes to the surface conductivity.
The contribution of the Stern layer is less well described. It is often called "additional surface conductivity".
The theory of the surface conductivity of the diffuse part of the DL was developed by Bikerman. He derived a simple equation that links surface conductivity κσ with the behaviour of ions at the interface. For symmetrical electrolyte and assuming identical ions diffusion coefficients D+=D−=D it is given in the reference:
where
F is the Faraday constant
T is the absolute temperature
R is the gas constant
C is the ionic concentration in the bulk fluid
z is the ion valency
ζ is the electrokinetic potential
The parameter m characterizes the contribution of electro-osmosis to the motion of ions within the DL:
The Dukhin n |
https://en.wikipedia.org/wiki/Journal%20of%20Micromechanics%20and%20Microengineering | The Journal of Micromechanics and Microengineering is a peer-reviewed scientific journal that covers all aspects of microelectromechanical systems, devices and structures, as well as micromechanics, microengineering, and microfabrication. The editor-in-chief is Weileun Fang (National Tsing Hua University).
Abstracting and indexing
The journal had a 2021 impact factor of 2.282 according to the Journal Citation Reports. It is indexed in Inspec, PASCAL, Current Contents/Engineering Computing and Technology, Science Citation Index, Chemical Abstracts, Mass Spectrometry Bulletin, Engineering Index/Compendex, Applied Mechanics Reviews, and VINITI Database RAS. |
https://en.wikipedia.org/wiki/Electrokinetic%20phenomena | Electrokinetic phenomena are a family of several different effects that occur in heterogeneous fluids, or in porous bodies filled with fluid, or in a fast flow over a flat surface. The term heterogeneous here means a fluid containing particles. Particles can be solid, liquid or gas bubbles with sizes on the scale of a micrometer or nanometer. There is a common source of all these effects—the so-called interfacial 'double layer' of charges. Influence of an external force on the diffuse layer generates tangential motion of a fluid with respect to an adjacent charged surface. This force might be electric, pressure gradient, concentration gradient, or gravity. In addition, the moving phase might be either continuous fluid or dispersed phase.
Family
Various combinations of the driving force and moving phase determine various electrokinetic effects. According to J.Lyklema, the complete family of electrokinetic phenomena includes:
electrophoresis, as motion of particles under influence of electric field;
electro-osmosis, as motion of liquid in porous body under influence of electric field;
diffusiophoresis, as motion of particles under influence of a chemical potential gradient;
capillary osmosis, as motion of liquid in porous body under influence of the chemical potential gradient;
sedimentation potential, as electric field generated by sedimenting colloid particles;
streaming potential/current, as either electric potential or current generated by fluid moving through porous body, or relative to flat surface;
colloid vibration current, as electric current generated by particles moving in fluid under influence of ultrasound;
electric sonic amplitude, as ultrasound generated by colloidal particles in oscillating electric field.
Further reading
There are detailed descriptions of electrokinetic phenomena in many books on interface and colloid science.
See also
Isotachophoresis
Onsager reciprocal relations
Surface charge
Cationization of cotton |
https://en.wikipedia.org/wiki/Brodel%27s%20bloodless%20line | Brodel's line, also known as Brodel's white line, is a relatively avascular line between the anterior and posterior segmental branches of the renal artery of the body. It has been proved that Brodel's line is also vascular.
Josef Hyrtl, in 1882, and Max Brödel, in 1902, described this relatively avascular plane near the midline (5 mm posterior) of the convex border of the kidney through which the collecting system of the kidney could be entered.
In continental Europe, credit for the plane was given to Hyrtl; but in England and the United States it was called the Brödel
bloodless line or the Brödel white line.
This plane is used for nephrolithotomy, more specifically while performing anatrophic nephrolithotomy. |
https://en.wikipedia.org/wiki/Windows%20Libraries%20for%20OS/2 | Windows Libraries for OS/2 Development Kit (WLO) is a collection of dynamic-link libraries for OS/2 that allow Win16 applications to run on OS/2.
See also
Microsoft Windows
Cardfile |
https://en.wikipedia.org/wiki/Cameron%E2%80%93Erd%C5%91s%20conjecture | In combinatorics, the Cameron–Erdős conjecture (now a theorem) is the statement that the number of sum-free sets contained in is
The sum of two odd numbers is even, so a set of odd numbers is always sum-free. There are odd numbers in [N ], and so subsets of odd numbers in [N ]. The Cameron–Erdős conjecture says that this counts a constant proportion of the sum-free sets.
The conjecture was stated by Peter Cameron and Paul Erdős in 1988. It was proved by Ben Green and independently by Alexander Sapozhenko in 2003.
See also
Erdős conjecture
Notes
Additive number theory
Combinatorics
Theorems in discrete mathematics
Paul Erdős
Conjectures that have been proved |
https://en.wikipedia.org/wiki/UNetbootin | UNetbootin ("Universal Netboot Installer") is a cross-platform utility that can create live USB systems and can load a variety of system utilities or install various Linux distributions and other operating systems without a CD.
Modes
USB install
This installation mode creates bootable USB flash drives and bootable USB Hard Disk Drives; it is a Live USB creator.
Cross-platform (available for Windows, Linux and Mac OS X)
Non-destructive install (does not format the device) using Syslinux.
Supports mainstream Linux distributions, such as Ubuntu, Fedora, openSUSE, CentOS, Gentoo, Linux Mint, Arch Linux, Mandriva, MEPIS, Slackware as well as FreeDOS, FreeBSD and NetBSD.
Can load a variety of system utilities, such as Ophcrack, BackTrack.
Other operating systems can be loaded via pre-downloaded ISO image or floppy/hard drive disk image files.
Automatically detects all removable devices.
Supports LiveUSB persistence (preserving files across reboots; this feature is for Ubuntu only)
Multiple installs on the same device are not supported.
Hard drive install
This installation mode performs a network installation or "frugal install" without a CD, similar to that performed by the Win32-Loader.
UNetbootin's distinguishing features are its support for a great variety of Linux distributions, its portability, its ability to load custom disk image (including ISO image) files, and its support for both Windows and Linux. Unlike Wubi, and similar to the Win32-Loader, when installing to hard disk, UNetbootin installs to a partition, not a disk image, thus creating a dual-boot setup between Linux and Windows.
Reception
A review in Full Circle in February 2021 stated, "despite the rather dated-looking interface, UNetbootin works perfectly, allowing the writing of almost any Linux or BSD distribution to a USB stick for testing or installation. It is a great example of the Unix philosophy: an application that does one thing and does it well."
See also
List of tools to cr |
https://en.wikipedia.org/wiki/Network%20virtualization | In computing, network virtualization is the process of combining hardware and software network resources and network functionality into a single, software-based administrative entity, a virtual network. Network virtualization involves platform virtualization, often combined with resource virtualization.
Network virtualization is categorized as either external virtualization, combining many networks or parts of networks into a virtual unit, or internal virtualization, providing network-like functionality to software containers on a single network server.
In software testing, software developers use network virtualization to test software which are under development in a simulation of the network environments in which the software is intended to operate. As a component of application performance engineering, network virtualization enables developers to emulate connections between applications, services, dependencies, and end users in a test environment without having to physically test the software on all possible hardware or system software. The validity of the test depends on the accuracy of the network virtualization in emulating real hardware and operating systems.
Components
Various equipment and software vendors offer network virtualization by combining any of the following:
Network hardware, such as switches and network adapters, also known as network interface cards (NICs)
Network elements, such as firewalls and load balancers
Networks, such as virtual LANs (VLANs) and containers such as virtual machines (VMs)
Network storage devices
Network machine-to-machine elements, such as telecommunications devices
Network mobile elements, such as laptop computers, tablet computers, and smartphones
Network media, such as Ethernet and Fibre Channel
External virtualization
External network virtualization combines or subdivides one or more local area networks (LANs) into virtual networks to improve a large network's or data center's efficiency. A virtual lo |
https://en.wikipedia.org/wiki/Mycoplasma%20laboratorium | Mycoplasma laboratorium or Synthia refers to a synthetic strain of bacterium. The project to build the new bacterium has evolved since its inception. Initially the goal was to identify a minimal set of genes that are required to sustain life from the genome of Mycoplasma genitalium, and rebuild these genes synthetically to create a "new" organism. Mycoplasma genitalium was originally chosen as the basis for this project because at the time it had the smallest number of genes of all organisms analyzed. Later, the focus switched to Mycoplasma mycoides and took a more trial-and-error approach.
To identify the minimal genes required for life, each of the 482 genes of M. genitalium was individually deleted and the viability of the resulting mutants was tested. This resulted in the identification of a minimal set of 382 genes that theoretically should represent a minimal genome. In 2008 the full set of M. genitalium genes was constructed in the laboratory with watermarks added to identify the genes as synthetic. However M. genitalium grows extremely slowly and M. mycoides was chosen as the new focus to accelerate experiments aimed at determining the set of genes actually needed for growth.
In 2010, the complete genome of M. mycoides was successfully synthesized from a computer record and transplanted into an existing cell of Mycoplasma capricolum that had had its DNA removed. It is estimated that the synthetic genome used for this project cost US$40 million and 200 man-years to produce. The new bacterium was able to grow and was named JCVI-syn1.0, or Synthia. After additional experimentation to identify a smaller set of genes that could produce a functional organism, JCVI-syn3.0 was produced, containing 473 genes. 149 of these genes are of unknown function. Since the genome of JCVI-syn3.0 is novel, it is considered the first truly synthetic organism.
Minimal genome project
The production of Synthia is an effort in synthetic biology at the J. Craig Venter Institute |
https://en.wikipedia.org/wiki/Adelchi%20Negri | Adelchi Negri (16 July 1876 – 19 February 1912) was an Italian pathologist and microbiologist born in Perugia.
He studied medicine and surgery at the University of Pavia, where he was a pupil of Camillo Golgi (1843–1926). After graduation in 1900, he became an assistant to Golgi at his pathological institute. In 1909 Negri became a professor of bacteriology, and the first official instructor of bacteriology in Pavia. On 19 February 1912 he died of tuberculosis at age 35.
Negri performed extensive research in the fields of histology, hematology, cytology, protozoology and hygiene. In 1903 he discovered the eponymous Negri bodies, defined as cytoplasmatic inclusion bodies located in the Purkinje cells of the cerebellum in cases of rabies in animals and humans. He documented his findings in an article titled Contributo allo studio dell'eziologia della rabbia, published in the journal Bollettino della Società medico-chirurgica. At the time, Negri mistakenly described the pathological agent of rabies as a parasitic protozoa. A few months later, Paul Remlinger (1871–1964) at the Constantinople Imperial Bacteriology Institute correctly demonstrated that the aetiological agent of rabies was not a protozoan, but a filterable virus.
Negri went on, however, to demonstrate in 1906 that the smallpox vaccine, then known as "vaccine virus", or "variola vaccinae", was also a filterable virus. During the latter part of his career, he became interested in malaria and was at the forefront in efforts to eradicate it from Lombardy. In 1906 he married his colleague Lina Luzzani and six years later, at the age of thirty-five, died of tuberculosis.
Tomb
Negri was buried in the Monumental Cemetery of Pavia (Viale San Giovannino), along the central lane, on the left, near the tombs of other two important medical scientists, the anatomist Bartolomeo Panizza and his teacher, the Nobel Prize–winning Camillo Golgi. |
https://en.wikipedia.org/wiki/Monochrome%20monitor | A monochrome monitor is a type of computer monitor in which computer text and images are displayed in varying tones of only one color, as opposed to a color monitor that can display text and images in multiple colors. They were very common in the early days of computing, from the 1960s through the 1980s, before color monitors became widely commercially available. They are still widely used in applications such as computerized cash register systems, owing to the age of many registers. Green screen was the common name for a monochrome monitor using a green "P1" phosphor screen; the term is often misused to refer to any block mode display terminal, regardless of color, e.g., IBM 3279, 3290.
Abundant in the early-to-mid-1980s, they succeeded Teletype terminals and preceded color CRTs and later LCDs as the predominant visual output device for computers.
CRT Design
The most common technology for monochrome monitors was the CRT, although, e.g., plasma displays, were also used.
Unlike color monitors, which display text and graphics in multiple colors through the use of alternating-intensity red, green, and blue phosphors, monochrome monitors have only one color of phosphor (mono means "one", and chrome means "color"). All text and graphics are displayed in that color. Some monitors have the ability to vary the brightness of individual pixels, thereby creating the illusion of depth and color, exactly like a black-and-white television.
Typically, only a limited set of brightness levels was provided to save display memory which was very expensive in the '70s and '80s. Either normal/bright or normal/dim (1 bit) per character as in the VT100 or black, dark gray, light gray, white (2bit) per pixel like the NeXT MegaPixel Display.
Monochrome monitors are commonly available in three colors: if the P1 phosphor is used, the screen is green monochrome. If the P3 phosphor is used, the screen is amber monochrome. If the P4 phosphor is used, the screen is white monochrome (known as |
https://en.wikipedia.org/wiki/Variance%20inflation%20factor | In statistics, the variance inflation factor (VIF) is the ratio (quotient) of the variance of estimating some parameter in a model that includes multiple other terms (parameters) by the variance of a model constructed using only one term. It quantifies the severity of multicollinearity in an ordinary least squares regression analysis. It provides an index that measures how much the variance (the square of the estimate's standard deviation) of an estimated regression coefficient is increased because of collinearity. Cuthbert Daniel claims to have invented the concept behind the variance inflation factor, but did not come up with the name.
Definition
Consider the following linear model with k independent variables:
Y = β0 + β1 X1 + β2 X 2 + ... + βk Xk + ε.
The standard error of the estimate of βj is the square root of the j + 1 diagonal element of s2(X′X)−1, where s is the root mean squared error (RMSE) (note that RMSE2 is a consistent estimator of the true variance of the error term, ); X is the regression design matrix — a matrix such that Xi, j+1 is the value of the jth independent variable for the ith case or observation, and such that Xi,1, the predictor vector associated with the intercept term, equals 1 for all i. It turns out that the square of this standard error, the estimated variance of the estimate of βj, can be equivalently expressed as:
where Rj2 is the multiple R2 for the regression of Xj on the other covariates (a regression that does not involve the response variable Y). This identity separates the influences of several distinct factors on the variance of the coefficient estimate:
s2: greater scatter in the data around the regression surface leads to proportionately more variance in the coefficient estimates
n: greater sample size results in proportionately less variance in the coefficient estimates
: greater variability in a particular covariate leads to proportionately less variance in the corresponding coefficient estimate
The remainin |
https://en.wikipedia.org/wiki/Loop%20performance | Loop performance in control engineering indicates the performance of control loops, such as a regulatory PID loop. Performance refers to the accuracy of a control system's ability to track (output) the desired signals to regulate the plant process variables in the most beneficial and optimised way, without delay or overshoot.
Importance
Regulatory control loops are critical in automated manufacturing and utility industries like refining, paper and chemicals manufacturing, power generation, among others. They are used to control a particular parameter within a process. The parameter that is being controlled could be temperature, pressure, flow or level of some process. For example, temperature controllers are used in boilers which are used in production of gasoline.
Software
There are many software applications that help in measuring and analysing the performance of control loops in industrial plants. Benchmarking the loop performance and identifying opportunities for improvement are key drivers for improving plant reliability, production throughput and safe operation. |
https://en.wikipedia.org/wiki/Chaetocladus | Chaetocladus is an extinct non-calcifying genus of unicellular green algae known from the Upper Silurian.
Morphology
Chaetocladus thalli range from 2–6 cm in height and average 1 cm in diameter. They comprise a parallel-sided, unbranching axis which is surrounded by leaf-like ramifications.
Fossil record
Chaetocladus is known from upper Silurian konservat lagerstätte, and found in association with other algae, arthropods, and annelid worms.
Similar Dasycladean algae are reported from late-Ordovician lagerstatte.
Classification
Due to its morphological similarity to the extant order Dasycladales, Chaetocladus is considered to be an early cousin of this order. Unlike the majority of Dasycladales, Chaetocladus does not form deposit calcite - therefore it required much rarer taphonomic conditions to be preserved.
Some genera now recognised as Chaetocladus were originally described as Graptolites.
Species
C. capitatus
C. dubius
C. gracilis
C. hefteri
C. plumula
C. ruedemanni |
https://en.wikipedia.org/wiki/Microsoft%20Help%202 | Microsoft Help 2.x is a proprietary format for online help files, developed by Microsoft and first released in 2001 as a help system for Visual Studio .NET (2002) and MSDN Library.
Microsoft Help 2.x is the help engine used in Microsoft Visual Studio 2002/2003/2005/2008 and Office 2007 and Office 2010. Help files are made with the Help 2.0 Workshop (VSHIK), a help authoring tool. The default viewer for Help 2.x files is Microsoft Document Explorer, and there are several third-party viewers available such as H2Viewer and Help Explorer Viewer.
Visual Studio 2010 uses a new help engine, Microsoft Help Viewer.
History
March 2001—Microsoft announced Microsoft Help 2.x at WritersUA (formerly WinWriters) conference.
January 2003—Microsoft decided not to release Microsoft Help 2 as a general Help platform. Help 2 remained a Visual Studio Help integration tool.
August 2003—Borland have released C# Builder. Documentation is all in Microsoft Help 2 format and displayed in Microsoft Document Explorer.
December 2005—Microsoft continues support of Help 2 by releasing the Help Integration Wizard which is Visual Studio 2005 compatible.
December 2006—Office 2007 is released and uses Microsoft Help 2. The Office help viewer is a custom viewer that can only view Office 2007 help.
April 2009—Microsoft announced at 2009 WritersUA conference that Microsoft Help System 1.x (development name was MS Help 3) will ship with Visual Studio 2010.
File format
A Microsoft Help 2.x file has a ".hxs" extension. A compressed .HxS help file (help title) is compiled from a set of topic pages written in a subset of HTML (much like its CHM predecessor), a .HxC main project file, an .HxF include file, a .HxT table of contents, a .HxA attribute definition file, and a number of .HxK indexes (keyword Index, NamedURL index, optional associated and context links indexes).
Specifics of the format can be found in an unofficial "ITOLITLS" format specification. An open source "convertlit" tool can be u |
https://en.wikipedia.org/wiki/Androdioecy | Androdioecy is a reproductive system characterized by the coexistence of males and hermaphrodites. Androdioecy is rare in comparison with the other major reproductive systems: dioecy, gynodioecy and hermaphroditism. In animals, androdioecy has been considered a stepping stone in the transition from dioecy to hermaphroditism, and vice versa.
Androdioecy is sometimes referred to as a mixed breeding system with trioecy and gynodioecy. It is a dimorphic sexual system in plants comparable with gynodioecy and dioecy.
Evolution of androdioecy
The fitness requirements for androdioecy to arise and sustain itself are theoretically so improbable that it was long considered that such systems do not exist. Particularly, males and hermaphrodites have to have the same fitness, in other words the same number of offspring, in order to be maintained. However, males only have offspring by fertilizing eggs or ovules of hermaphrodites, while hermaphrodites have offspring both through fertilizing eggs or ovules of other hermaphrodites and their own ovules. This means that all else being equal, males have to fertilize twice as many eggs or ovules as hermaphrodites to make up for the lack of female reproduction.
Androdioecy can evolve either from hermaphroditic ancestors through the invasion of males or from dioecious ancestors through the invasion of hermaphrodites. The ancestral state is important because conditions under which androdioecy can evolve differ significantly.
Androdioecy with dioecious ancestry
In roundworms, clam shrimp, tadpole shrimp and cancrid shrimps, androdioecy has evolved from dioecy. In these systems, hermaphrodites can only fertilize their own eggs (self-fertilize) and do not mate with other hermaphrodites. Males are the only means of outcrossing. Hermaphrodites may be beneficial in colonizing new habitats, because a single hermaphrodite can generate many other individuals.
In the well-studied roundworm Caenorhabditis elegans, males are very rare and only |
https://en.wikipedia.org/wiki/International%20Council%20for%20Industrial%20and%20Applied%20Mathematics | The International Council for Industrial and Applied Mathematics (ICIAM) is an organisation for professional applied mathematics societies and related organisations. The current (2020) President is Ya-xiang Yuan.
History
Until 1999 the Council was known as the Committee for International Conferences on Industrial and Applied Mathematics (CICIAM). Formed in 1987 with the start of the ICIAM conference series, this committee represented the leaders of four applied mathematics societies: the Gesellschaft für Angewandte Mathematik und Mechanik (GAMM), in Germany, the Institute of Mathematics and its Applications (IMA), in England, the Society for Industrial and Applied Mathematics (SIAM), in the USA, and the Société de Mathématiques Appliquées et Industrielles (SMAI), in France. The first two presidents of the council, Roger Temam and Reinhard Mennicken, oversaw the addition of several other societies as members and associate members of the council; as of 2015 it had 21 full members and 26 associate members. Past Presidents include Olavi Nevanlinna, Ian Sloan, Rolf Jeltsch, Barbara Keyfitz, and María J. Esteban.
Congress
ICIAM organizes the four-yearly International Congress on Industrial and Applied Mathematics, the first of which was held in 1987. The most recent congress was in 2019 in Valencia (Spain), and the next will be in 2023 in Tokyo (Japan). It also sponsors several prizes, awarded at the congresses: the Lagrange Prize for exceptional career contributions, the Collatz Prize for outstanding applied mathematicians under the age of 42, the Pioneer Prize for applied mathematical work in a new field, the Maxwell Prize for originality in applied mathematics, and the Su Buchin Prize for outstanding contributions to emerging economies and human development.
Collatz Prize
The Collatz Prize is awarded by ICIAM every four years at the International Congress on Industrial and Applied Mathematics, to an applied mathematician under the age of 42. It was established in 19 |
https://en.wikipedia.org/wiki/International%20Congress%20on%20Industrial%20and%20Applied%20Mathematics | The International Congress on Industrial and Applied Mathematics (ICIAM) is an international congress in the field of applied mathematics held every four years under the auspices of the International Council for Industrial and Applied Mathematics. The initial proposal for this conference series was made by Gene Golub.
List of congresses
ICIAM 1987 – Paris
ICIAM 1991 – Washington, D.C.
ICIAM 1995 – Hamburg
ICIAM 1999 – Edinburgh
ICIAM 2003 – Sydney
ICIAM 2007 – Zurich
ICIAM 2011 – Vancouver
ICIAM 2015 – Beijing
ICIAM 2019 – Valencia
ICIAM 2023 – Tokyo
See also
Society for Industrial and Applied Mathematics
International Congress of Mathematics |
https://en.wikipedia.org/wiki/Least-squares%20spectral%20analysis | Least-squares spectral analysis (LSSA) is a method of estimating a frequency spectrum based on a least-squares fit of sinusoids to data samples, similar to Fourier analysis. Fourier analysis, the most used spectral method in science, generally boosts long-periodic noise in the long and gapped records; LSSA mitigates such problems. Unlike in Fourier analysis, data need not be equally spaced to use LSSA.
Developed in 1969 and 1971, LSSA is also known as the Vaníček method and the Gauss-Vaniček method after Petr Vaníček, and as the Lomb method or the Lomb–Scargle periodogram, based on the simplifications first by Nicholas R. Lomb and then by Jeffrey D. Scargle.
Historical background
The close connections between Fourier analysis, the periodogram, and the least-squares fitting of sinusoids have been known for a long time.
However, most developments are restricted to complete data sets of equally spaced samples. In 1963, Freek J. M. Barning of Mathematisch Centrum, Amsterdam, handled unequally spaced data by similar techniques, including both a periodogram analysis equivalent to what nowadays is called the Lomb method and least-squares fitting of selected frequencies of sinusoids determined from such periodograms — and connected by a procedure known today as the matching pursuit with post-back fitting or the orthogonal matching pursuit.
Petr Vaníček, a Canadian geophysicist and geodesist of the University of New Brunswick, proposed in 1969 also the matching-pursuit approach for equally and unequally spaced data, which he called "successive spectral analysis" and the result a "least-squares periodogram". He generalized this method to account for any systematic components beyond a simple mean, such as a "predicted linear (quadratic, exponential, ...) secular trend of unknown magnitude", and applied it to a variety of samples, in 1971.
Vaníček's strictly least-squares method was then simplified in 1976 by Nicholas R. Lomb of the University of Sydney, who pointed out i |
https://en.wikipedia.org/wiki/Aircraft%20disinsection | Aircraft disinsection is the use of insecticide on international flights and in other closed spaces for insect and disease control. Confusion with disinfection, the elimination of microbes on surfaces, is not uncommon. Insect vectors of disease, mostly mosquitoes, have been introduced into and become indigenous in geographic areas where they were not previously present. Dengue, chikungunya and Zika spread across the Pacific and into the Americas by means of the airline networks. Cases of "airport malaria", in which live malaria-carrying mosquitoes disembark and infect people near the airport, may increase with global warming.
Definitions in the International Health Regulations (IHR) of the World Health Organization are:
"Disinfection" means the procedure whereby health measures are taken to control or kill infectious agents on a human or animal body surface or in or on baggage, cargo, containers, conveyances, goods and postal parcels by direct exposure to chemical or physical agents.
“Disinsection” means the procedure whereby health measures are taken to control or kill the insect vectors of human diseases present in baggage, cargo, containers, conveyances, goods and postal parcels.
Disinsection is mandated by the IHR. The WHO recommends d-phenothrin (2%) for space spraying and permethrin (2%) for residual disinsection. Neither is harmful when used as recommended, according to WHO. Disinsection is one of two applications of the IHR likely to be encountered by travelers; yellow fever vaccination is the other. |
https://en.wikipedia.org/wiki/Island%2035%20Mastodon | The Island 35 Mastodon was discovered on Island No. 35 of the Mississippi River in Tipton County, Tennessee, United States.
In 1900, a Pleistocene mastodon skeleton was excavated approximately east of Reverie, Tennessee and southeast of Wilson, Arkansas. In 1957 the site was reported as destroyed.
Mastodons are members of the prehistoric, extinct genus Mammut. They resemble modern elephants.
Native to North America, they are said to have lived on the North American continent from almost 4 million years ago, in the Pliocene Epoch, until their eventual disappearance about 10,000 years ago.
Discovery
In 1900, archaeologist James K. Hampson documented the discovery of skeletal remains of a mastodon on Island No. 35 of the Mississippi River, Tipton County, Tennessee. The site of the prehistoric find is approximately east of Reverie, Tennessee and south of Blytheville, Arkansas.
During heavy rain in June 1900, sand at the point bar of Island No. 35 had been washed away, exposing the mastodon skeleton in the sediment when the water retreated from the sandbar in July of the same year.
John Pendleton, a resident of Island No. 35, notified his neighbor James K. Hampson about unusual bones he had found exposed by the retreating water at the head of the river island. Reportedly, Hampson visited the site of the find "2 or 3 weeks" after the prehistoric bones had been discovered.
By the time of Hampson's arrival, many of the bones had been stolen and the skeleton had been considerably damaged by "curiosity seekers" and "ivory hunters". The remainder of the skeleton ("mainly parts of the hind leg and pelvis") were excavated by Hampson with the help of a pick to separate the mastodon bones from the gravel and pebbles in which they had been resting "cemented together by a clay".
Although this find was initially believed to be the remains of a single animal, Morse and Morse subsequently reported that the site consisted of at least two separate mastodons. Several human ar |
https://en.wikipedia.org/wiki/Outrunner | An outrunner is an electric motor having the rotor outside the stator, as though the motor were turned inside out. They are often used in radio-controlled model aircraft.
This type of motor spins its outer shell around its windings, much like motors found in ordinary CD-ROM computer drives. In fact, CD-ROM motors are frequently rewound into brushless outrunner motors for small park flyer aircraft. Parts to aid in converting CD-ROM motors to aircraft use are commercially available.
Usually, outrunners have more poles, so they spin much slower than their inrunner counterparts with their more traditional layout (though still considerably faster than ferrite motors, when compared with motors that use neodymium magnets) while producing far more torque. This makes an outrunner an excellent choice for directly driving electric aircraft propellers since they eliminate the extra weight, complexity, inefficiency and noise of a gearbox. Some front loading direct-drive washing machines use an outrunner motor.
Outrunner motors have quickly become popular and are now available in many sizes. They have also become popular in personal, electric transportation applications such as electric bikes and scooters due to their compact size and high efficiency.
240 sailplanes of eleven different types from seven manufacturers are equipped with the FES propulsion system from LZ Design d.o.o of Slovenia. The 22 kW provides enough power for lighter 13.5-15m gliders to self-launch and allow heavier gliders with enough power to climb and then maintain height, so avoiding an unscheduled out-landing. Its synchronous permanent magnet motor has an electronically controlled commutation system.
Stator and magnetic pole count
The stationary (stator) windings of an outrunner motor are excited by conventional DC brushless motor controllers. A direct current (switched on and off at high frequency for voltage modulation) is typically passed through three or more non-adjacent windings together, and |
https://en.wikipedia.org/wiki/Amelioration%20pattern | In software engineering, an amelioration pattern is an anti-pattern formed when an existing software design pattern was edited (i.e. rearranged, added or deleted) to better suit a particular problem so as to achieve some further effect or behavior. In this sense, an amelioration pattern is transformational in character. |
https://en.wikipedia.org/wiki/Repeating%20decimal | A repeating decimal or recurring decimal is decimal representation of a number whose digits are periodic (repeating its values at regular intervals) and the infinitely repeated portion is not zero. It can be shown that a number is rational if and only if its decimal representation is repeating or terminating (i.e. all except finitely many digits are zero). For example, the decimal representation of becomes periodic just after the decimal point, repeating the single digit "3" forever, i.e. 0.333.... A more complicated example is , whose decimal becomes periodic at the second digit following the decimal point and then repeats the sequence "144" forever, i.e. 5.8144144144.... At present, there is no single universally accepted notation or phrasing for repeating decimals. Another example of this is , which becomes periodic after the decimal point, repeating the 13-digit pattern "1886792452830" forever, i.e. 11.18867924528301886792452830....
The infinitely repeated digit sequence is called the repetend or reptend. If the repetend is a zero, this decimal representation is called a terminating decimal rather than a repeating decimal, since the zeros can be omitted and the decimal terminates before these zeros. Every terminating decimal representation can be written as a decimal fraction, a fraction whose denominator is a power of 10 (e.g. ); it may also be written as a ratio of the form (e.g. ). However, every number with a terminating decimal representation also trivially has a second, alternative representation as a repeating decimal whose repetend is the digit 9. This is obtained by decreasing the final (rightmost) non-zero digit by one and appending a repetend of 9. Two examples of this are and . (This type of repeating decimal can be obtained by long division if one uses a modified form of the usual division algorithm.)
Any number that cannot be expressed as a ratio of two integers is said to be irrational. Their decimal representation neither terminates nor infi |
https://en.wikipedia.org/wiki/N%2CN%27-Diisopropylcarbodiimide | {{DISPLAYTITLE:N,N'''-Diisopropylcarbodiimide}}
{{chembox
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 424839902
| Name =
| ImageFile = N,N'-methanediylidenebis(propan-2-amine) 200.svg
| ImageSize = 220
| ImageFile1 = N,N'-Diisopropylcarbodiimide molecule ball.png
| ImageSize1 = 240
| ImageAlt1 = Ball-and-stick model of the N,N'-diisopropylcarbodiimide molecule
| PIN = N,N-Di(propan-2-yl)methanediimine
| OtherNames = Diisopropylmethanediimine, DIC
|Section1=
|Section2=
|Section3=
}}N,-Diisopropylcarbodiimide' is a carbodiimide used in peptide synthesis. As a liquid, it is easier to handle than the commonly used N,-dicyclohexylcarbodiimide, a waxy solid. In addition, N,''-diisopropylurea, its byproduct in many chemical reactions, is soluble in most organic solvents, a property that facilitates work-up.
Further reading
Peptide coupling reagents
Carbodiimides
Reagents for biochemistry
Biochemistry
Biochemistry methods
Isopropylamino compounds |
https://en.wikipedia.org/wiki/Dickson%20Prize | The Dickson Prize in Medicine and the Dickson Prize in Science were both established in 1969 by Joseph Z. Dickson and Agnes Fischer Dickson.
Dickson Prize in Medicine
The Dickson Prize in Medicine is awarded annually by the University of Pittsburgh and recognizes US citizens who have made "significant, progressive contributions" to medicine. The award includes $50,000, a bronze medal, and the Dickson Prize Lecture.
Recipients
Source: University of Pittsburgh
1971 Earl W. Sutherland Jr.
1972 Solomon A. Berson and Rosalyn S. Yalow
1973 John H. Gibbon Jr.
1974 Stephen W. Kuffler
1975 Elizabeth F. Neufeld
1976 Frank J. Dixon
1977 Roger Guillemin
1978 Paul Greengard
1979 Bert W. O'Malley
1980 David H. Hubel and Torsten N. Wiesel
1981 Philip Leder
1982 Francis H. Ruddle
1983 Eric R. Kandel
1984 Solomon H. Snyder
1985 Robert C. Gallo
1986 J. Michael Bishop
1987 Elvin A. Kabat
1988 Leroy E. Hood
1989 Bernard Moss
1990 Ernst Knobil
1991 Phillip A. Sharp
1992 Francis Sellers Collins
1993 Stanley B. Prusiner
1994 Bert Vogelstein
1995 Ronald M. Evans
1996 Philippa Marrack
1997 Ed Harlow and Eric Steven Lander
1998 Richard D. Klausner
1999 James E. Darnell Jr.
2000 Elizabeth H. Blackburn (Dickson Prize Lecture, April 13, 2000: "Telomere Capping and Cell Proliferation")
2001 Robert G. Roeder (Dickson Prize Lecture, September 12, 2001: "Regulation of Transcription in Human Cells: Complexities and Challenges")
2002 C. David Allis (Dickson Prize Lecture, September 18, 2002: "Translating the Histone Code: A Tale of Tails")
2003 Susan L. Lindquist (Dickson Prize Lecture, September 24, 2003: "Protein Conformation as a Pathway to Understanding Cellular Processes, Disease and Bio-Inspired Materials")
2004 Elaine Fuchs (Dickson Prize Lecture, 2004: "Skin Stem Cells and Their Lineages")
2005 Ronald W. Davis (Dickson Prize Lecture, 2005: "New Genomic Technology for Yeast Applied to Clinical Medicine")
2006 Roger D. Kornberg (Dickson Prize Lecture, O |
https://en.wikipedia.org/wiki/Pissalat | Pissalat or pissala is a condiment originating from the Nice region of France. The name comes from peis salat in Niçard and means 'salted fish'. It is made from anchovy puree flavoured with cloves, thyme, bay leaf and black pepper mixed with olive oil. Pissalat is used for flavouring hors d'oeuvres, fish, cold meats and, especially, the local specialty, pissaladière.
Etymology
The word pissala (in Nissard) or pissalat (in French) is composed of the old Provençal word peis for 'fish', and sala, the past participle of salar, which corresponds to the French saler ('to salt'). Together, they describe "preserves of small crushed and salted fish" or, similarly, "a piquant sauce made from the maceration of salted fish".
History
The pissalat is similar to the siqqu, from the Mesopotamian Culinary Treatise of the 2nd millennium BC. J.-C. (c. 1700 BC) or with garum (juice or sauce, in Latin, from Roman antiquity). Since the time of ancient Rome, garum has been produced (with many variants) throughout the Mediterranean basin. It is a sauce obtained by the maceration in salt of heads and intestines of mackerel, sardines, anchovies and aromatic plants. The sauce thus obtained, passed through a fine sieve, was recovered with a ladle, and was preserved in olive oil.
The manufacture of pissalat was a centuries-old local industry in the Nice-Côte d'Azur region, where the salting of sardines and anchovies employed roughly a dozen families at the beginning of the 19th century. The Niçois writer, Louis Roubaudi, notes in his 1843 book Nice and its surroundings: "The pissalat is very suitable for reviving the appetite when it is seasoned with olive oil, vinegar and salted olives."
The sauce largely disappeared from commerce during the Second World War, and exists today only in the form of local traditional artisanal and family production (it is often replaced by salted anchovies or anchovy purée), in particular for the preparation of pissaladière.
Recipe
The pissalat sauce is |
https://en.wikipedia.org/wiki/OAuth | OAuth (short for "Open Authorization") is an open standard for access delegation, commonly used as a way for internet users to grant websites or applications access to their information on other websites but without giving them the passwords. This mechanism is used by companies such as Amazon, Google, Facebook, Microsoft, and Twitter to permit users to share information about their accounts with third-party applications or websites.
Generally, the OAuth protocol provides a way for resource owners to provide a client [application] with secure delegated access to server resources. It specifies a process for resource owners to authorize third-party access to their server resources without providing credentials. Designed specifically to work with Hypertext Transfer Protocol (HTTP), OAuth essentially allows access tokens to be issued to third-party clients by an authorization server, with the approval of the resource owner. The third party then uses the access token to access the protected resources hosted by the resource server.
History
OAuth began in November 2006 when Blaine Cook was developing the Twitter OpenID implementation. Meanwhile, Ma.gnolia needed a solution to allow its members with OpenIDs to authorize Dashboard Widgets to access their service. Cook, Chris Messina and Larry Halff from Magnolia met with David Recordon to discuss using OpenID with the Twitter and Magnolia APIs to delegate authentication. They concluded that there were no open standards for API access delegation.
The OAuth discussion group was created in April 2007, for a small group of implementers to write the draft proposal for an open protocol. DeWitt Clinton from Google learned of the OAuth project, and expressed his interest in supporting the effort. In July 2007, the team drafted an initial specification. Eran Hammer joined and coordinated the many OAuth contributions creating a more formal specification. On 4 December 2007, the OAuth Core 1.0 final draft was released.
At the 73rd |
https://en.wikipedia.org/wiki/Hybrid-pi%20model | Hybrid-Pi is a popular circuit model used for analyzing the small signal behavior of bipolar junction and field effect transistors. Sometimes it is also called Giacoletto model because it was introduced by L.J. Giacoletto in 1969. The model can be quite accurate for low-frequency circuits and can easily be adapted for higher frequency circuits with the addition of appropriate inter-electrode capacitances and other parasitic elements.
BJT parameters
The hybrid-pi model is a linearized two-port network approximation to the BJT using the small-signal base-emitter voltage, , and collector-emitter voltage, , as independent variables, and the small-signal base current, , and collector current, , as dependent variables.
A basic, low-frequency hybrid-pi model for the bipolar transistor is shown in figure 1. The various parameters are as follows.
is the transconductance, evaluated in a simple model, where:
is the quiescent collector current (also called the collector bias or DC collector current)
is the thermal voltage, calculated from Boltzmann's constant, , the charge of an electron, , and the transistor temperature in kelvins, . At approximately room temperature (295K, 22°C or 71°F), is about 25 mV.
where:
is the DC (bias) base current.
is the current gain at low frequencies (generally quoted as hfe from the h-parameter model). This is a parameter specific to each transistor, and can be found on a datasheet.
is the output resistance due to the Early effect ( is the Early voltage).
Related terms
The output conductance, g, is the reciprocal of the output resistance, r:
.
The transresistance, r, is the reciprocal of the transconductance:
.
Full model
The full model introduces the virtual terminal, B', so that the base spreading resistance, rbb, (the bulk resistance between the base contact and the active region of the base under the emitter) and rb'e (representing the base current required to make up for recombination of minority carriers in the base regio |
https://en.wikipedia.org/wiki/Similarity%20search | Similarity search is the most general term used for a range of mechanisms which share the principle of searching (typically, very large) spaces of objects where the only available comparator is the similarity between any pair of objects. This is becoming increasingly important in an age of large information repositories where the objects contained do not possess any natural order, for example large collections of images, sounds and other sophisticated digital objects.
Nearest neighbor search and range queries are important subclasses of similarity search, and a number of solutions exist. Research in similarity search is dominated by the inherent problems of searching over complex objects. Such objects cause most known techniques to lose traction over large collections, due to a manifestation of the so-called curse of dimensionality, and there are still many unsolved problems. Unfortunately, in many cases where similarity search is necessary, the objects are inherently complex.
The most general approach to similarity search relies upon the mathematical notion of metric space, which allows the construction of efficient index structures in order to achieve scalability in the search domain.
Similarity search evolved independently in a number different scientific and computing contexts, according to various needs. In 2008 a few leading researchers in the field felt strongly that the subject should be a research topic in its own right, to allow focus on the general issues applicable across the many diverse domains of its use. This resulted in the formation of the SISAP foundation, whose main activity is a series of annual international conferences on the generic topic.
Metric search
Metric search is similarity search which takes place within metric spaces. While the semimetric properties are more or less necessary for any kind of search to be meaningful, the further property of triangle inequality is useful for engineering, rather than conceptual, purposes.
A simp |
https://en.wikipedia.org/wiki/Waring%27s%20prime%20number%20conjecture | In number theory, Waring's prime number conjecture is a conjecture related to Vinogradov's theorem, named after the English mathematician Edward Waring. It states that every odd number exceeding 3 is either a prime number or the sum of three prime numbers. It follows from the generalized Riemann hypothesis, and (trivially) from Goldbach's weak conjecture.
See also
Schnirelmann's constant |
https://en.wikipedia.org/wiki/Cauchy%E2%80%93Hadamard%20theorem | In mathematics, the Cauchy–Hadamard theorem is a result in complex analysis named after the French mathematicians Augustin Louis Cauchy and Jacques Hadamard, describing the radius of convergence of a power series. It was published in 1821 by Cauchy, but remained relatively unknown until Hadamard rediscovered it. Hadamard's first publication of this result was in 1888; he also included it as part of his 1892 Ph.D. thesis.
Theorem for one complex variable
Consider the formal power series in one complex variable z of the form
where
Then the radius of convergence of f at the point a is given by
where denotes the limit superior, the limit as approaches infinity of the supremum of the sequence values after the nth position. If the sequence values are unbounded so that the is ∞, then the power series does not converge near , while if the is 0 then the radius of convergence is ∞, meaning that the series converges on the entire plane.
Proof
Without loss of generality assume that . We will show first that the power series converges for , and then that it diverges for .
First suppose . Let not be or
For any , there exists only a finite number of such that .
Now for all but a finite number of , so the series converges if . This proves the first part.
Conversely, for , for infinitely many , so if , we see that the series cannot converge because its nth term does not tend to 0.
Theorem for several complex variables
Let be a multi-index (a n-tuple of integers) with , then converges with radius of convergence (which is also a multi-index) if and only if
to the multidimensional power series
The proof can be found in
Notes
External links
Augustin-Louis Cauchy
Mathematical series
Theorems in complex analysis |
https://en.wikipedia.org/wiki/Pathatrix | Pathatrix is a high volume recirculating immuno magnetic-capture system developed by Thermo Fisher Scientific (and supplier parts by Life Technologies) for the detection of pathogens in food and environmental samples.
History
Pathatrix and its Pathatrix Recirculating Immunomagnetic Separation System (RIMS) was used in 2006 to detect the E. coli O157:H7 strain in contaminated spinach using a polymerase chain reaction (PCR). The Pathatrix system is used by regulatory agencies and food companies around the world as a reliable method for detecting pathogens in food.
Unlike other detection methods, Pathatrix allows the entire pre-enriched sample or large pooled samples to be recirculated over antibody-coated paramagnetic beads. It can specifically isolate pathogens directly from food samples and in conjunction with quantitative PCR can provide results within hours. It is also used to improve the performance of other rapid methods such as PCR, lateral flow, ELISA and chromogenic media by reducing or eliminating the need for lengthy pre-enrichment and/or selective enrichment steps. The Pathatrix is useful in pathogen labs that would be running food samples and looking for foodborne diseases.
The Pathatrix is a rapid test method and Pathatrix pooling allows the screening of large numbers of food samples in a highly cost-effective way for specific pathogens such as E. coli O157, Salmonella or Listeria monocytogenes.
The Pathatrix will selectively bind and purify the target organism from a comprehensive range of complex food matrices (including raw ground beef, chocolate, peanut butter, leafy greens, spinach, tomatoes). The Pathatrix is a microbial detection system that allows for the entire sample to be analyzed. |
https://en.wikipedia.org/wiki/First%20Hurwitz%20triplet | In the mathematical theory of Riemann surfaces, the first Hurwitz triplet is a triple of distinct Hurwitz surfaces with the identical automorphism group of the lowest possible genus, namely 14 (genera 3 and 7 each admit a unique Hurwitz surface, respectively the Klein quartic and the Macbeath surface). The explanation for this phenomenon is arithmetic. Namely, in the ring of integers of the appropriate number field, the rational prime 13 splits as a product of three distinct prime ideals. The principal congruence subgroups defined by the triplet of primes produce Fuchsian groups corresponding to the triplet of Riemann surfaces.
Arithmetic construction
Let be the real subfield of where is a 7th-primitive root of unity.
The ring of integers of K is , where . Let be the quaternion algebra, or symbol algebra . Also Let and . Let . Then is a maximal order of (see Hurwitz quaternion order), described explicitly by Noam Elkies [1].
In order to construct the first Hurwitz triplet, consider the prime decomposition of 13 in , namely
where is invertible. Also consider the prime ideals generated by the non-invertible factors. The principal congruence subgroup defined by such a prime ideal I is by definition the group
namely, the group of elements of reduced norm 1 in equivalent to 1 modulo the ideal . The corresponding Fuchsian group is obtained as the image of the principal congruence subgroup under a representation to PSL(2,R).
Each of the three Riemann surfaces in the first Hurwitz triplet can be formed as a Fuchsian model, the quotient of the hyperbolic plane by one of these three Fuchsian groups.
Bound for systolic length and the systolic ratio
The Gauss–Bonnet theorem states that
where is the Euler characteristic of the surface and is the Gaussian curvature . In the case we have
and
thus we obtain that the area of these surfaces is
.
The lower bound on the systole as specified in [2], namely
is 3.5187.
Some specific details about each o |
https://en.wikipedia.org/wiki/Bryant%20surface | In Riemannian geometry, a Bryant surface is a 2-dimensional surface embedded in 3-dimensional hyperbolic space with constant mean curvature equal to 1. These surfaces take their name from the geometer Robert Bryant, who proved that every simply-connected minimal surface in 3-dimensional Euclidean space is isometric to a Bryant surface by a holomorphic parameterization analogous to the (Euclidean) Weierstrass–Enneper parameterization. |
https://en.wikipedia.org/wiki/Presenilin-1 | Presenilin-1 (PS-1) is a presenilin protein that in humans is encoded by the PSEN1 gene. Presenilin-1 is one of the four core proteins in the gamma secretase complex, which is considered to play an important role in generation of amyloid beta (Aβ) from amyloid-beta precursor protein (APP). Accumulation of amyloid beta is associated with the onset of Alzheimer's disease.
Structure
Presenilin possesses a 9 transmembrane domain topology, with an extracellular C-terminus and a cytosolic N-terminus. Presenilin undergoes endo-proteolytic processing to produce ~27-28 kDa N-terminal and ~16-17 kDa C-terminal fragments in humans. Furthermore, presenilin exists in the cell mainly as a heterodimer of the C-terminal and N-terminus fragments. When presenilin 1 is overexpressed, the full length protein accumulates in an inactive form. Based on evidence that a gamma-secretase inhibitor binds to the fragments, the cleaved presenilin complex is considered to be the active form.
Function
Presenilins are postulated to regulate APP processing through their effects on gamma secretase, an enzyme that cleaves APP. Also, it is thought that the presenilins are involved in the cleavage of the Notch receptor, such that they either directly regulate gamma secretase activity or themselves are protease enzymes. Multiple alternatively spliced transcript variants have been identified for this gene, the full-length natures of only some have been determined.
Notch signaling pathway
In Notch signaling, critical proteolytic reactions takes place during maturation and activation of Notch membrane receptor. Notch1 is cleaved extracellularlly at site1 (S1) and two polypeptides are produced to form a heterodimer receptor on the cell surface. After the formation of receptor, Notch1 is further cleaved in site 3(S3) and release Notch1 intracellular domain (NICD) from the membrane.
Presenilin 1 has been shown to play an important role in proteolytic process. In the prenilin 1 null mutant drosophila, |
https://en.wikipedia.org/wiki/Injection%20locking | Injection locking and injection pulling are the frequency effects that can occur when a harmonic oscillator is disturbed by a second oscillator operating at a nearby frequency. When the coupling is strong enough and the frequencies near enough, the second oscillator can capture the first oscillator, causing it to have essentially identical frequency as the second. This is injection locking. When the second oscillator merely disturbs the first but does not capture it, the effect is called injection pulling. Injection locking and pulling effects are observed in numerous types of physical systems, however the terms are most often associated with electronic oscillators or laser resonators.
Injection locking has been used in beneficial and clever ways in the design of early television sets and oscilloscopes, allowing the equipment to be synchronized to external signals at a relatively low cost. Injection locking has also been used in high performance frequency doubling circuits. However, injection locking and pulling, when unintended, can degrade the performance of phase-locked loops and RF integrated circuits.
Injection from grandfather clocks to lasers
Injection pulling and injection locking can be observed in numerous physical systems where pairs of oscillators are coupled together. Perhaps the first to document these effects was Christiaan Huygens, the inventor of the pendulum clock, who was surprised to note that two pendulum clocks which normally would keep slightly different time nonetheless became perfectly synchronized when hung from a common beam. Modern researchers have confirmed his suspicion that the pendulums were coupled by tiny back-and-forth vibrations in the wooden beam. The two clocks became injection locked to a common frequency.
In a modern-day voltage-controlled oscillator an injection-locking signal may override its low-frequency control voltage, resulting in loss of control. When intentionally employed, injection locking provides a mea |
https://en.wikipedia.org/wiki/Microprocessor%20chronology |
1970s
The first microprocessors were designed and manufactured in the 1970s. Intel's 4004 of 1971 is widely regarded as the first commercial microprocessor.
Designers predominantly used MOSFET transistors with pMOS logic in the early 1970s, switching to nMOS logic after the mid-1970s. nMOS had the advantage that it could run on a single voltage, typically +5V, which simplified the power supply requirements and allowed it to be easily interfaced with the wide variety of +5V transistor-transistor logic (TTL) devices. nMOS had the disadvantage that it was more susceptible to electronic noise generated by slight impurities in the underlying silicon material, and it was not until the mid-1970s that these, sodium in particular, were successfully removed to the required levels. At that time, around 1975, nMOS quickly took over the market.
This corresponded with the introduction of new semiconductor masking systems, notably the Micralign system from Perkin-Elmer. Micralign projected an image of the mask onto the silicon wafer, never touching it directly, which eliminated the previous problems when the mask would be lifted off the surface and take away some of the photoresist along with it, ruining the chips on that portion of the wafer. By reducing the number of flawed chips, from about 70% to 10%, the cost of complex designs like early microprocessors fell by the same amount. Systems based on contact aligners cost on the order of $300 in single-unit quantities, the MOS 6502, designed specifically to take advantage of these improvements, cost only $25.
This period also saw considerable experimentation with various word lengths. Early on, 4-bit processors were common, like the Intel 4004, simply because making a wider word length could not be accomplished cost-effectively in the room available on the small wafers of the era, especially when the majority would be defective. As yields improved, wafer sizes grew, and feature size continued to be reduced, more complex 8-bit |
https://en.wikipedia.org/wiki/Churchill%E2%80%93Bernstein%20equation | In convective heat transfer, the Churchill–Bernstein equation is used to estimate the surface averaged Nusselt number for a cylinder in cross flow at various velocities. The need for the equation arises from the inability to solve the Navier–Stokes equations in the turbulent flow regime, even for a Newtonian fluid. When the concentration and temperature profiles are independent of one another, the mass-heat transfer analogy can be employed. In the mass-heat transfer analogy, heat transfer dimensionless quantities are replaced with analogous mass transfer dimensionless quantities.
This equation is named after Stuart W. Churchill and M. Bernstein, who introduced it in 1977. This equation is also called the Churchill–Bernstein correlation.
Heat transfer definition
where:
is the surface averaged Nusselt number with characteristic length of diameter;
is the Reynolds number with the cylinder diameter as its characteristic length;
is the Prandtl number.
The Churchill–Bernstein equation is valid for a wide range of Reynolds numbers and Prandtl numbers, as long as the product of the two is greater than or equal to 0.2, as defined above. The Churchill–Bernstein equation can be used for any object of cylindrical geometry in which boundary layers develop freely, without constraints imposed by other surfaces. Properties of the external free stream fluid are to be evaluated at the film temperature in order to account for the variation of the fluid properties at different temperatures. One should not expect much more than 20% accuracy from the above equation due to the wide range of flow conditions that the equation encompasses. The Churchill–Bernstein equation is a correlation and cannot be derived from principles of fluid dynamics. The equation yields the surface averaged Nusselt number, which is used to determine the average convective heat transfer coefficient. Newton's law of cooling (in the form of heat loss per surface area being equal to heat transfer coefficien |
https://en.wikipedia.org/wiki/Burst%20mode%20clock%20and%20data%20recovery | The passive optical network (PON) uses tree-like network topology. Due to the topology of PON, the transmission modes for downstream (that is, from optical line termination, (OLT) to optical network unit (ONU)) and upstream (that is, from ONU to OLT) are different. For the downstream transmission, the OLT broadcasts optical signal to all the ONUs in continuous mode (CM), that is, the downstream channel always has optical data signal. One given ONU can find which frame in the CM stream is for it by reading the header of the frame. However, in the upstream channel, ONUs can not transmit optical data signal in CM. It is because that all the signals transmitted from the ONUs converge (with attenuation) into one fiber by the power splitter (serving as power coupler), and overlap among themselves if CM is used. To solve this problem, burst mode (BM) transmission is adopted for upstream channel. The given ONU only transmits optical packet when it is allocated a time slot and it needs to transmit, and all the ONUs share the upstream channel in the time division multiple access (TDMA) mode. The phases of the BM optical packets received by the OLT are different from packet to packet, since the ONUs are not synchronized to transmit optical packet in the same phase, and the distance between OLT and given ONU are random. In order to compensate the phase variation from packet to packet, burst mode clock and data recovery (BM-CDR) is required. Such circuit can generate local clock with the frequency and phase same as the individual received optical packet in a short locking time, for example within 40 ns. Such generated local clock can in turn perform correct data decision. Above all, the clock and data recovery can be performed correctly after a short locking time.
The conventionally used PLL based clock recovery schemes can not meet such strict requirement on locking time. Various other schemes have been invented, including those employing gated oscillator or injection locked o |
https://en.wikipedia.org/wiki/The%20Collapse%20of%20Chaos | The Collapse of Chaos: Discovering Simplicity in a Complex World (1994) is a book about complexity theory and the nature of scientific explanation written by biologist Jack Cohen and mathematician Ian Stewart.
In this book Cohen and Stewart give their ideas on chaos theory, particularly on how the simple leads to the complex, and conversely, how the complex leads to the simple, and argue for a need for contextual explanation in science as a complement to reduction. This book dovetails with other books written by the Cohen-Stewart team, particularly Figments of Reality.
As with other Cohen-Stewart books, topics are illustrated with humorous science fiction snippets dealing with a fictional alien intelligence, the Zarathustrians, whom Cohen and Stewart use as metaphors of the human mind itself.
Reception
Next Generation commented, "Although the book assumes you have zero knowledge of science (and thus is a little patronizing in the early chapters), it presents the concepts of Complexity Theory as well as anything we've seen."
Additional reviews |
https://en.wikipedia.org/wiki/Schr%C3%B6dinger%20field | In quantum mechanics and quantum field theory, a Schrödinger field, named after Erwin Schrödinger, is a quantum field which obeys the Schrödinger equation. While any situation described by a Schrödinger field can also be described by a many-body Schrödinger equation for identical particles, the field theory is more suitable for situations where the particle number changes.
A Schrödinger field is also the classical limit of a quantum Schrödinger field, a classical wave which satisfies the Schrödinger equation. Unlike the quantum mechanical wavefunction, if there are interactions between the particles the equation will be nonlinear. These nonlinear equations describe the classical wave limit of a system of interacting identical particles.
The path integral of a Schrödinger field is also known as a coherent state path integral, because the field itself is an annihilation operator whose eigenstates can be thought of as coherent states of the harmonic oscillations of the field modes.
Schrödinger fields are useful for describing Bose–Einstein condensation, the Bogolyubov–de Gennes equation of superconductivity, superfluidity, and many-body theory in general. They are also a useful alternative formalism for nonrelativistic quantum mechanics.
A Schrödinger field is the nonrelativistic limit of a Klein–Gordon field.
Summary
A Schrödinger field is a quantum field whose quanta obey the Schrödinger equation. In the classical limit, it can be understood as the quantized wave equation of a Bose Einstein condensate or a superfluid.
Free field
A Schrödinger field has the free field Lagrangian
When is a complex valued field in a path integral, or equivalently an operator with canonical commutation relations, it describes a collection of identical non-relativistic bosons. When is a Grassmann valued field, or equivalently an operator with canonical anti-commutation relations, the field describes identical fermions.
External potential
If the particles interact with an extern |
https://en.wikipedia.org/wiki/Radium%20Dial%20Company | The Radium Dial Company was one of a few now defunct United States companies, along with the United States Radium Corporation, involved in the painting of clocks, watches and other instrument dials using radioluminescent paint containing radium. The resulting dials are now collectively known as radium dials. The luminous paint used on the dials contained a mixture of Zinc Sulfide which was activated with Silver and then powdered radium, a product that the Radium Dial Company named Luma. However, unlike the US Radium Corporation, Radium Dial Company was specifically set up to only paint dials, and no other radium processing took place at the premises.
History
The Radium Dial Company was started in 1917 and was in full production of painted dials by 1918. The company was a division of the Standard Chemical Company based in the Marshall Field Annex building in Chicago. In 1920 the company relocated to Peru, Illinois to closer proximity to the clock manufacturer and major customer, Westclox.
By 1922 the company had moved to a former high school building in Ottawa, Illinois where it remained until the mid-1930s. At the highest point in production (around 1925), the Radium Dial Company employed around 1,000 young women who turned out around 4,300 dials each day.
The company was headed by Joseph A. Kelly, Sr. Kelly opened up a new corporation called Luminous Processes Inc. a few blocks away from the Radium Dial Company in Ottawa, Illinois shortly after closing down the Radium Dial Company. Luminous Processes Inc. continued producing fluorescent watch dials powered by radium radioactivity until 1978.
See also
Radium Girls
Radium jaw
Radioluminescence |
https://en.wikipedia.org/wiki/Pseudo-modal%20energies | Pseudo-modal energies are used for estimating the energy content of a mechanical system near its resonance frequencies. They are defined as the integral of the frequency response function within a certain bandwidth around a resonance. |
https://en.wikipedia.org/wiki/Deep%20fascia%20of%20leg | The deep fascia of leg, or crural fascia forms a complete investment to the muscles, and is fused with the periosteum over the subcutaneous surfaces of the bones.
The deep fascia of the leg is continuous above with the fascia lata (deep fascia of the thigh), and is attached around the knee to the patella, the patellar ligament, the tuberosity and condyles of the tibia, and the head of the fibula.
Behind, it forms the popliteal fascia, covering in the popliteal fossa; here it is strengthened by transverse fibers, and perforated by the small saphenous vein.
It receives an expansion from the tendon of the biceps femoris laterally, and from the tendons of the sartorius, gracilis, semitendinosus, and semimembranosus medially; in front, it blends with the periosteum covering the subcutaneous surface of the tibia, and with that covering the head and malleolus of the fibula; below, it is continuous with the transverse crural and laciniate ligaments.
It is thick and dense in the upper and anterior part of the leg, and gives attachment, by its deep surface, to the tibialis anterior and extensor digitorum longus; but thinner behind, where it covers the gastrocnemius and soleus.
It gives off from its deep surface, on the lateral side of the leg, two strong intermuscular septa, the anterior and posterior peroneal septa, which enclose the fibularis (peroneus) longus and brevis muscles and separate them from the muscles of the anterior and posterior crural regions, and several more slender processes which enclose the individual muscles in each region.
A broad transverse intermuscular septum, called the deep transverse fascia of the leg, intervenes between the superficial and deep posterior crural muscles. |
https://en.wikipedia.org/wiki/Allegory%20%28mathematics%29 | In the mathematical field of category theory, an allegory is a category that has some of the structure of the category Rel of sets and binary relations between them. Allegories can be used as an abstraction of categories of relations, and in this sense the theory of allegories is a generalization of relation algebra to relations between different sorts. Allegories are also useful in defining and investigating certain constructions in category theory, such as exact completions.
In this article we adopt the convention that morphisms compose from right to left, so means "first do , then do ".
Definition
An allegory is a category in which
every morphism is associated with an anti-involution, i.e. a morphism with and and
every pair of morphisms with common domain/codomain is associated with an intersection, i.e. a morphism
all such that
intersections are idempotent: commutative: and associative:
anti-involution distributes over intersection:
composition is semi-distributive over intersection: and and
the modularity law is satisfied:
Here, we are abbreviating using the order defined by the intersection: means
A first example of an allegory is the category of sets and relations. The objects of this allegory are sets, and a morphism is a binary relation between and . Composition of morphisms is composition of relations, and the anti-involution of is the converse relation : if and only if . Intersection of morphisms is (set-theoretic) intersection of relations.
Regular categories and allegories
Allegories of relations in regular categories
In a category , a relation between objects and is a span of morphisms that is jointly monic. Two such spans and are considered equivalent when there is an isomorphism between and that make everything commute; strictly speaking, relations are only defined up to equivalence (one may formalise this either by using equivalence classes or by using bicategories). If the category has products, a relation b |
https://en.wikipedia.org/wiki/Applicability%20domain | The applicability domain (AD) (for both chemistry and machine learning) of a QSAR model is the physico-chemical, structural or biological space, knowledge or information on which the training set of the model has been developed, and for which it is applicable to make predictions for new compounds.
The purpose of AD is to state whether the model's assumptions are met, and for which chemicals the model can be reliably applicable. In general, this is the case for interpolation rather than for extrapolation. Up to now there is no single generally accepted algorithm for determining the AD: a comprehensive survey can be found in a Report and Recommendations of ECVAM Workshop 52. There exists a rather systematic approach for defining interpolation regions. The process involves the removal of outliers and a probability density distribution method using kernel-weighted sampling.
Another widely used approach for the structural AD of the regression QSAR models is based on the leverage calculated from the diagonal values of the hat matrix of the modeling molecular descriptors.
A recent rigorous benchmarking study of several AD algorithms identified standard-deviation of model predictions as the most reliable approach.
To investigate the AD of a training set of chemicals one can directly analyse properties of the multivariate descriptor space of the training compounds or more indirectly via distance (or similarity) metrics. When using distance metrics care should be taken to use an orthogonal and significant vector space. This can be achieved by different means of feature selection and successive principal components analysis.
Notes
Cheminformatics
Medicinal chemistry
Drug discovery |
https://en.wikipedia.org/wiki/JY%20cell%20line | The JY cell line is an Epstein–Barr virus (EBV)-immortalised B cell lymphoblastoid line. JY cells express HLA class-I A2 and class-II DR. JY is a suspension cell line, although the cells are known to grow in clumps. The growth medium is RPMI 1640, 10% fetal calf serum and 1% L-glutamine. JY cells are positive for murine leukemia virus. |
https://en.wikipedia.org/wiki/Hosaka%E2%80%93Cohen%20transformation | Hosaka–Cohen transformation (also called H–C transformation) is a mathematical method of converting a particular two-dimensional scalar magnetic field map to a particular two-dimensional vector map. The scalar field map is of the component of magnetic field which is normal to a two-dimensional surface of a volume conductor; this volume conductor contains the currents producing the magnetic field. The resulting vector map, sometimes called "an arrowmap" roughly mimics those currents under the surface which are parallel to the surface, which produced the field. Therefore, the purpose in performing the transformation is to allow a rough visualization of the underlying, parallel currents.
The transformation was proposed by Cohen and Hosaka of the biomagnetism group at MIT, then was used by Hosaka and Cohen to visualize the current sources of the magnetocardiogram.
Each arrow is defined as:
where of the local coordinate system is normal to the volume conductor surface, and are unit vectors, and is the normal component of magnetic field. This is a form of two-dimensional gradient of the scalar quantity and is rotated by 90° from the conventional gradient.
Almost any scalar field, magnetic or otherwise, can be displayed in this way, if desired, as an aid to the eye, to help see the underlying sources of the field.
See also
Biomagnetism
Bioelectromagnetism
Electrophysiology
Magnetic field
Magnetocardiography
Magnetometer
Notes
Further reading
Biophysics
Medical imaging |
https://en.wikipedia.org/wiki/Simple%20Sloppy%20Semantic%20Database | Simple Sloppy Semantic Database (S3DB) is a distributed data management system that relies on Semantic Web concepts for management of heterogeneous data.
S3DB is open source software, licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License. It is written in PHP.
History
S3DB was first proposed in 2006, following the argumentation the previous year that omics data sets would be more easily managed if stored as RDF triples.
The first version, 1.0, was focused on the support of an indexing engine for triplestore management.
The second version, made available in October 2007, added cross-referencing between triples in distinct S3DB deployments to support it as a distributed infrastructure.
The third version was released in July 2008 and exposes its API through a specialized query language, S3QL, accessible as a REST web service. An update of that release (version 3.5) also includes a RESTful SPARQL endpoint. This update introduced a self-update feature which replaces version numbers by date of update.
In 2011, S3DB's API was published and was put to use in the management of a clinical trial at MDAnderson Cancer Center using a web application with a self-assembled interface.
Assessments
The rationale, core data model, and usage in National Cancer Institute (NIH/NCI) SPORE awards are described and illustrated in a 2008 PLoS ONE manuscript and a 2010 BMC Bioinformatics manuscript.
A 2012 survey paper stated, "S3QL supports a permission control mechanism that allows users to specify contextual minutiae such as provenance and access control on the semantic level. The effectiveness of S3QL was illustrated through use cases of IB, such as genomic characterization of cancer and molecular epidemiology of infectious diseases. We expect S3QL or its variations to be accepted as the standard access control mechanism by the SW community".
External links
S3DB homepage
S3DB source code
S3QL specification
S3DB tutorial video, YouTu |
https://en.wikipedia.org/wiki/Indo-1 | Indo-1 is a popular calcium indicator similar to Fura-2. In contrast to Fura-2, Indo-1 has a dual emissions peak. The main emission peak in calcium-free solution is 475 nm while in the presence of calcium the emission is shifted to 400 nm. It is widely used in flow cytometry.
The penta potassium salt is commercially available and preferred to the free acid because of its higher solubility in water. While Indo-1 is not cell permeable the penta acetoxymethyl ester Indo-1 AM enters the cell where it is cleaved by intracellular esterases to Indo-1.
The synthesis and properties of Indo-1 were presented in 1985 by the group of Roger Y Tsien. |
https://en.wikipedia.org/wiki/Sperm-mediated%20gene%20transfer | Sperm-mediated gene transfer (SMGT) is a transgenic technique that transfers genes based on the ability of sperm cells to spontaneously bind to and internalize exogenous DNA and transport it into an oocyte during fertilization to produce genetically modified animals.1 Exogenous DNA refers to DNA that originates outside of the organism. Transgenic animals have been obtained using SMGT, but the efficiency of this technique is low. Low efficiency is mainly due to low uptake of exogenous DNA by the spermatozoa, reducing the chances of fertilizing the oocytes with transfected spermatozoa.2 In order to successfully produce transgenic animals by SMGT, the spermatozoa must attach the exogenous DNA into the head and these transfected spermatozoa must maintain their functionality to fertilize the oocyte.2 Genetically modified animals produced by SMGT are useful for research in biomedical, agricultural, and veterinary fields of study. SMGT could also be useful in generating animals as models for human diseases or lead to future discoveries relating to human gene therapy.
Sperm-Mediated Gene Transfer Mechanism
The method for SMGT uses the sperm cell, a natural vector of genetic material, to transport exogenous DNA. The exogenous DNA molecules bind to the cell membrane of the head of the sperm cell. This binding and internalization of the DNA is not a random event. The exogenous DNA interacts with the DNA-binding proteins (DBPs) that are present on the surface of the sperm cell.3 Spermatozoa are naturally protected against the intrusion of exogenous DNA molecules by an inhibitory factor present in mammals’ seminal fluid. This factor blocks the binding of sperm cells and exogenous DNA because in the presence of the inhibitory factor, DBPs lose their ability to bind to exogenous DNA. In the absence of this inhibitory factor, DBPs on sperm cells are able to interact with DNA and can then translocate the DNA into the cell. Therefore, the seminal fluid must be removed from the sper |
https://en.wikipedia.org/wiki/Lema%C3%AEtre%20coordinates | Lemaître coordinates are a particular set of coordinates for the Schwarzschild metric—a spherically symmetric solution to the Einstein field equations in vacuum—introduced by Georges Lemaître in 1932. Changing from Schwarzschild to Lemaître coordinates removes the coordinate singularity at the Schwarzschild radius.
Equations
The original Schwarzschild coordinate expression of the Schwarzschild metric, in natural units (), is given as
where
is the invariant interval;
is the Schwarzschild radius;
is the mass of the central body;
are the Schwarzschild coordinates (which asymptotically turn into the flat spherical coordinates);
is the speed of light;
and is the gravitational constant.
This metric has a coordinate singularity at the Schwarzschild radius .
Georges Lemaître was the first to show that this is not a real physical singularity but simply a manifestation of the fact that the static Schwarzschild coordinates cannot be realized with material bodies inside the Schwarzschild radius. Indeed, inside the Schwarzschild radius everything falls towards the centre and it is impossible for a physical body to keep a constant radius.
A transformation of the Schwarzschild coordinate system from to the new coordinates
(the numerator and denominator are switched inside the square-roots), leads to the Lemaître coordinate expression of the metric,
where
The trajectories with ρ constant are timelike geodesics with τ the proper time along these geodesics. They represent the motion of freely falling particles which start out with zero velocity at infinity. At any point their speed is just equal to the escape velocity from that point.
In Lemaître coordinates the metric is non-singular at the Schwarzschild radius r=1, which instead corresponds to the point . However, there remains a genuine gravitational singularity at the center, where , which cannot be removed by a coordinate change.
The Lemaître coordinate system is synchronous, that is, the global time coordina |
https://en.wikipedia.org/wiki/Geodesic%20map | In mathematics—specifically, in differential geometry—a geodesic map (or geodesic mapping or geodesic diffeomorphism) is a function that "preserves geodesics". More precisely, given two (pseudo-)Riemannian manifolds (M, g) and (N, h), a function φ : M → N is said to be a geodesic map if
φ is a diffeomorphism of M onto N; and
the image under φ of any geodesic arc in M is a geodesic arc in N; and
the image under the inverse function φ−1 of any geodesic arc in N is a geodesic arc in M.
Examples
If (M, g) and (N, h) are both the n-dimensional Euclidean space En with its usual flat metric, then any Euclidean isometry is a geodesic map of En onto itself.
Similarly, if (M, g) and (N, h) are both the n-dimensional unit sphere Sn with its usual round metric, then any isometry of the sphere is a geodesic map of Sn onto itself.
If (M, g) is the unit sphere Sn with its usual round metric and (N, h) is the sphere of radius 2 with its usual round metric, both thought of as subsets of the ambient coordinate space Rn+1, then the "expansion" map φ : Rn+1 → Rn+1 given by φ(x) = 2x induces a geodesic map of M onto N.
There is no geodesic map from the Euclidean space En onto the unit sphere Sn, since they are not homeomorphic, let alone diffeomorphic.
The gnomonic projection of the hemisphere to the plane is a geodesic map as it takes great circles to lines and its inverse takes lines to great circles.
Let (D, g) be the unit disc D ⊂ R2 equipped with the Euclidean metric, and let (D, h) be the same disc equipped with a hyperbolic metric as in the Poincaré disc model of hyperbolic geometry. Then, although the two structures are diffeomorphic via the identity map i : D → D, i is not a geodesic map, since g-geodesics are always straight lines in R2, whereas h-geodesics can be curved.
On the other hand, when the hyperbolic metric on D is given by the Klein model, the identity i : D → D is a geodesic map, because hyperbolic geodesics in the Klein model are (Euclidean) straigh |
https://en.wikipedia.org/wiki/Bead%20probe%20technology | Bead probe technology (BPT) is technique used to provide electrical access (called “nodal access”) to printed circuit board (PCB) circuitry for performing in-circuit testing (ICT). It makes use of small beads of solder placed onto the board's traces to allow measuring and controlling of the signals using a test probe. This permits test access to boards on which standard ICT test pads are not feasible due to space constraints.
Description
Bead probe technology is a probing method used to connect electronic test equipment to the device under test (DUT) within a bed of nails fixture. The technique was first used in the 1990s and originally given the name “Waygood Bump” after one of the main proponents, Rex Waygood. They are also commonly referred to as solder bumps. Bead probes were designed for when less than 30 mil is available for test probe points on the PCB. They are used with standard ICT spring-loaded test probes to connect the test equipment to the DUT.
Bead construction
Bead probes are made from a very small "beads" of solder that fit atop of the PCB traces. They are manufactured using the same techniques as other solder features. Construction requires a hole to be opened in the solder mask, exposing the copper trace. This hole is sized to precisely control the amount of metal that forms the bead. Solder paste is applied to the location and reflowed. During reflow, solder flows and is drawn to the copper trace. Surface tension causes the bead to have a curved surface and rise above the solder mask, where it solidifies into a Bead Probe. The bead will be roughly obround in shape and may be 15-25 mils long. A properly constructed bead is the same width as the trace and just enough to clear the surrounding solder mask. The bead is then accessible for testing using a probe with a flat end, which can help compensate for the tolerance build up in the test fixture and PCB.
Advantages
Bead probe can be used in circuits where the pin-pitch is too fine to allow s |
https://en.wikipedia.org/wiki/Upstream%20and%20downstream%20%28DNA%29 | In molecular biology and genetics, upstream and downstream both refer to relative positions of genetic code in DNA or RNA. Each strand of DNA or RNA has a 5' end and a 3' end, so named for the carbon position on the deoxyribose (or ribose) ring. By convention, upstream and downstream relate to the 5' to 3' direction respectively in which RNA transcription takes place. Upstream is toward the 5' end of the RNA molecule and downstream is toward the 3' end. When considering double-stranded DNA, upstream is toward the 5' end of the coding strand for the gene in question and downstream is toward the 3' end. Due to the anti-parallel nature of DNA, this means the 3' end of the template strand is upstream of the gene and the 5' end is downstream.
Some genes on the same DNA molecule may be transcribed in opposite directions. This means the upstream and downstream areas of the molecule may change depending on which gene is used as the reference.
The terms upstream and downstream are sometimes also applied to a polypeptide sequence, where upstream refers to a region N-terminal and downstream to residues C-terminal of a reference point.
See also
Upstream and downstream (transduction) |
https://en.wikipedia.org/wiki/Upstream%20and%20downstream%20%28transduction%29 | The upstream signaling pathway is triggered by the binding of a signaling molecule, a ligand, to a receiving molecule, a receptor. Receptors and ligands exist in many different forms, and only recognize/bond to particular molecules. Upstream extracellular signaling transduce a variety of intracellular cascades.
Receptors and ligands are common upstream signaling molecules that dictate the downstream elements of the signal pathway. A plethora of different factors affect which ligands bind to which receptors and the downstream cellular response that they initiate.
TGF-β
The extracellular type II and type I kinase receptors binding to the TGF-β ligands. Transforming growth factor-β (TGF-β) is a superfamily of cytokines that play a significant upstream role in regulating of morphogenesis, homeostasis, cell proliferation, and differentiation. The significance of TGF-β is apparent with the human diseases that occur when TGF-β processes are disrupted, such as cancer, and skeletal, intestinal and cardiovascular diseases. TGF-β is pleiotropic and multifunctional, meaning they are able to act on a wide variety of cell types.
Mechanism
The effects of transforming growth factor-β (TGF-β) are determined by cellular context. There are three kinds of contextual factors that determine the shape the TGF-β response: the signal transduction components, the transcriptional cofactors and the epigenetic state of the cell. The different ligands and receptors of TGF-β are significant as well in the composition signal transduction pathway.
the signal transduction components: ligand isoforms, ligand traps, co-receptors, receptor sub-types, inhibitory SMAD proteins, crosstalk inputs
the transcriptional cofactors of SMAD proteins: pluripotency factors, lineage regulators, DNA-binding cofactors, HATs and HDACs, SNF, chromatin readers
the epigenetic factors: heterochromatin, pluripotency marks, lineage marks, EMT marks, iPS cell marks, oncogenic marks.
Upstream pathway
The type II re |
https://en.wikipedia.org/wiki/Norwegian%20Black%20List | The Norwegian Black List (Fremmedartslista) is an overview of alien species in Norway, with ecological risk assessments for some of the species. The Norwegian Black List was first published in 2007 by the Norwegian Biodiversity Information Centre and developed in cooperation with 18 scientific experts from six research institutions.
The 2007 Norwegian Black List is the first issue, and is compiled as a counterpart to the Norwegian Red List of 2006.
The 2007 Norwegian Black List
The 2007 Norwegian Black List contains a total of 2483 species of plants, animals and other organisms, 217 of which are risk assessed. A set of criteria has been developed to ensure a standardised assessment of the ecological consequences of alien species.
The assessed species are placed in categories according to the risk they represent.
High risk - 93 species
Unknown risk - 83 species
Low risk - 41 species
Alien species on Svalbard, Bjørnøya and Jan Mayen are not assessed.
Result
Among the 93 species which are found to threaten the natural local biodiversity, are bacteria, macroalgae, microalgae, pseudofungi, fungi, mosses, vascular plants, comb jellies, flatworms, roundworms, crustaceans, arachnids, insects, snails, bivalves, tunicates, fishes and mammals.
Among the vascular plants with a high risk, are Heracleum tromsoensis (aka Heracleum persicum), sycamore maple (Acer pseudoplatanus) and garden lupin (Lupinus polyphyllus). Among the flatworms; Gyrodactylus salaris, among the crustaceans the red king crab (Paralithodes camtschaticus) and American lobster (Homarus americanus). Five species of mammals are noted as high risk species; West European hedgehog, European rabbit, southern vole, American mink and raccoon.
See also
IUCN Red List |
https://en.wikipedia.org/wiki/Open%20Virtualization%20Format | Open Virtualization Format (OVF) is an open standard for packaging and distributing virtual appliances or, more generally, software to be run in virtual machines.
The standard describes an "open, secure, portable, efficient and extensible format for the packaging and distribution of software to be run in virtual machines". The OVF standard is not tied to any particular hypervisor or instruction set architecture. The unit of packaging and distribution is a so-called OVF Package which may contain one or more virtual systems each of which can be deployed to a virtual machine.
History
In September 2007 VMware, Dell, HP, IBM, Microsoft and XenSource submitted to the Distributed Management Task Force (DMTF) a proposal for OVF, then named "Open Virtual Machine Format".
The DMTF subsequently released the OVF Specification V1.0.0 as a preliminary standard in September, 2008, and V1.1.0 in January, 2010. In January 2013, DMTF released the second version of the standard, OVF 2.0 which applies to emerging cloud use cases and provides important developments from OVF 1.0 including improved network configuration support and package encryption capabilities for safe delivery.
ANSI has ratified OVF 1.1.0 as ANSI standard INCITS 469-2010.
OVF 1.1 was adopted in August 2011 by ISO/IEC JTC 1/SC 38 of the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) as an International Standard ISO/IEC 17203.
OVF 2.0 brings an enhanced set of capabilities to the packaging of virtual machines, making the standard applicable to a broader range of cloud use cases that are emerging as the industry enters the cloud era. The most significant improvements include support for network configuration along with the ability to encrypt the package to ensure safe delivery.
Design
An OVF package consists of several files placed in one directory. An OVF package always contains exactly one OVF descriptor (a file with extension .ovf). The OVF descrip |
https://en.wikipedia.org/wiki/Aseptic%20processing | Aseptic processing is a processing technique wherein commercially thermally sterilized liquid products (typically food or pharmaceutical) are packaged into previously sterilized containers under sterile conditions to produce shelf-stable products that do not need refrigeration. Aseptic processing has almost completely replaced in-container sterilization of liquid foods, including milk, fruit juices and concentrates, cream, yogurt, salad dressing, liquid egg, and ice cream mix. There has been an increasing popularity for foods that contain small discrete particles, such as cottage cheese, baby foods, tomato products, fruit and vegetables, soups, and rice desserts.
Aseptic processing involves three primary steps: thermal sterilization of the product, sterilization of the packaging material, and conservation of sterility during packaging. To ensure commercial sterility, aseptic processing facilities are required to maintain proper documentation of production operations, showing that commercially sterile conditions were achieved and maintained in all areas of the facility. Any breach of a scheduled process for the processing or packaging system means that the affected product must be destroyed, reprocessed or segregated and held for further evaluation. In addition, the processing and packaging system must be cleaned and re-sterilized before processing and/or packaging operations can resume. Packaging equipment and packaging materials are sterilized with various media or combinations thereof (i.e., saturated steam, superheated steam, hydrogen peroxide and heat and other treatments).
Historical development in foods
Aseptic processing was derived from Olin Ball's heat-cool-fill (HCF) machine that was developed in 1927. While HCF was successful in improving the sensory quality of the processed chocolate milk as compared to canned product, the use of the equipment was hindered by its cost, maintenance, and inflexibility to process various container sizes, rendering the ma |
https://en.wikipedia.org/wiki/C%20Sharp%20syntax | This article describes the syntax of the C# programming language. The features described are compatible with .NET Framework and Mono.
Basics
Identifier
An identifier is the name of an element in the code. It can contain letters, digits and underscores (_), and is case sensitive (FOO is different from foo). The language imposes the following restrictions on identifier names:
They cannot start with a digit;
They cannot start with a symbol, unless it is a keyword;
They cannot contain more than 511 characters.
Identifier names may be prefixed by an at sign (@), but this is insignificant; @name is the same identifier as name.
Microsoft has published naming conventions for identifiers in C#, which recommends the use of PascalCase for the names of types and most type members, and camelCase for variables and for private or internal fields. However, these naming conventions are not enforced in the language.
Keywords
Keywords are predefined reserved words with special syntactic meaning. The language has two types of keyword — contextual and reserved. The reserved keywords such as false or byte may only be used as keywords. The contextual keywords such as where or from are only treated as keywords in certain situations. If an identifier is needed which would be the same as a reserved keyword, it may be prefixed by an at sign to distinguish it. For example, @out is interpreted as an identifier, whereas out as a keyword. This syntax facilitates reuse of .NET code written in other languages.
The following C# keywords are reserved words:
abstract
as
base
bool
break
byte
case
catch
char
checked
class
const
continue
decimal
default
delegate
do
double
else
enum
event
explicit
extern
false
finally
fixed
float
for
foreach
goto
if
implicit
in
int
interface
internal
is
lock
long
namespace
new
null
object
operator
out
override
params
private
protected
public
readonly
ref
return
sbyte
sealed
short
sizeof
stackalloc
stati |
https://en.wikipedia.org/wiki/False%20morel | The name false morel is given to several species of mushroom which bear a resemblance to the highly regarded true morels of the genus Morchella. Like Morchella, false morels are members of the Pezizales, but within that group represent several unrelated taxa scattered through the families Morchellaceae, Discinaceae, and Helvellaceae, with the epithet "false morel" most often ascribed to members of the genus Gyromitra.
Compared to morels
When gathering morels for mushrooms, care must be taken to distinguish them from potentially poisonous lookalikes. While a great many morel lookalikes, and even morels themselves are toxic or cause gastrointestinal upset when consumed raw, some, such as Gyromitra esculenta remain toxic even after conventional cooking methods. Although some false morels can be eaten without ill effect, others can cause severe gastrointestinal upset, loss of muscular coordination (including cardiac muscle), or even death. Incidents of poisoning usually occur when they are eaten in large quantities, inadequately cooked, or over several days in a row. Some species contain gyromitrin, a toxic and carcinogenic organic compound, which is hydrolyzed in the body into monomethylhydrazine (MMH). Gyromitra esculenta in particular has been reported to be responsible for up to 23% of mushroom fatalities each year in Poland. G. esculenta—regarded as delicious—is known to be potentially deadly when eaten fresh, but research in the 1990s showed that toxins remain even after proper treatment. While many people freely eat false morels, potentially even toxic species, without apparent harm, some people have developed acute toxicity and recent evidence suggests that there may be long-term health risks as well.
The key morphological features distinguishing some of the false morels from true morels are as follows:
Gyromitra species often have a "wrinkled" or "cerebral" (brain-like) appearance to the cap due to multiple wrinkles and folds, rather than the honeycomb a |
https://en.wikipedia.org/wiki/Cough%20center | The cough center is a region of the brain which controls coughing. The cough center is located in the medulla oblongata in the brainstem. Cough suppressants focus their action on the cough center.
Structure
The exact location and functionality of the cough center has remained somewhat elusive: while Johannes Peter Müller observed in 1838 that the medulla coordinates the cough reflex, investigating it has been slow because the usual anaesthetics for experimental animals were morphine or opiates, drugs which strongly inhibit cough. In addition, the center likely overlaps with the respiratory rhythm generator networks. It is hence not so much a specific area, but a function within the respiration and reflex networks of the brainstem.
Cough receptors project to relay neurones in the solitary nucleus, which project to other parts of the respiratory networks. In particular, the pre-Bötzinger complex may act as a pattern generator for the cough response. Parts of the caudal medullary raphe nucleus (nucleus raphe obscurus and nucleus raphe magnus) are known to be essential for the cough response. Other systems that may be involved in pattern generation and regulation are the pontine respiratory group, the lateral tegmental field and the deep cerebellar nuclei. Successful joint models of medullary systems coordinating breathing, coughing and swallowing has been constructed based on this model.
Coughing can occur or be inhibited as a voluntary action, suggesting control from higher systems in the brain. Functional brain imaging of voluntary, suppressed, and induced coughing show that a number of cortical areas can get involved and may be important even for non-voluntary coughing. In contrast, voluntary coughing does not seem to activate medullary systems. |
https://en.wikipedia.org/wiki/Linear%20partial%20information | Linear partial information (LPI) is a method of making decisions based on insufficient or fuzzy information. LPI was introduced in 1970 by Polish–Swiss mathematician Edward Kofler (1911–2007) to simplify decision processes. Compared to other methods the LPI-fuzziness is algorithmically simple and particularly in decision making, more practically oriented. Instead of an indicator function the decision maker linearizes any fuzziness by establishing of linear restrictions for fuzzy probability distributions or normalized weights. In the LPI-procedure the decision maker linearizes any fuzziness instead of applying a membership function. This can be done by establishing stochastic and non-stochastic LPI-relations. A mixed stochastic and non-stochastic fuzzification is often a basis for the LPI-procedure. By using the LPI-methods any fuzziness in any decision situation can be considered on the base of the linear fuzzy logic.
Definition
Any Stochastic Partial Information SPI(p), which can be considered as a solution of a linear inequality system, is called Linear Partial Information LPI(p) about probability p. It can be considered as an LPI-fuzzification of the probability p corresponding to the concepts of linear fuzzy logic.
Applications
The MaxEmin Principle
To obtain the maximally warranted expected value, the decision maker has to choose the strategy which maximizes the minimal expected value. This procedure leads to the MaxEmin – Principle and is an extension of the Bernoulli's principle.
The MaxWmin Principle
This principle leads to the maximal guaranteed weight function, regarding the extreme weights.
The Prognostic Decision Principle (PDP)
This principle is based on the prognosis interpretation of strategies under fuzziness.
Fuzzy equilibrium and stability
Despite the fuzziness of information, it is often necessary to choose the optimal, most cautious strategy, for example in economic planning, in conflict situations or in daily decisions. This is impossi |
https://en.wikipedia.org/wiki/Malliavin%27s%20absolute%20continuity%20lemma | In mathematics — specifically, in measure theory — Malliavin's absolute continuity lemma is a result due to the French mathematician Paul Malliavin that plays a foundational rôle in the regularity (smoothness) theorems of the Malliavin calculus. Malliavin's lemma gives a sufficient condition for a finite Borel measure to be absolutely continuous with respect to Lebesgue measure.
Statement of the lemma
Let μ be a finite Borel measure on n-dimensional Euclidean space Rn. Suppose that, for every x ∈ Rn, there exists a constant C = C(x) such that
for every C∞ function φ : Rn → R with compact support. Then μ is absolutely continuous with respect to n-dimensional Lebesgue measure λn on Rn. In the above, Dφ(y) denotes the Fréchet derivative of φ at y and ||φ||∞ denotes the supremum norm of φ. |
https://en.wikipedia.org/wiki/Double%20layer%20%28plasma%20physics%29 | A double layer is a structure in a plasma consisting of two parallel layers of opposite electrical charge. The sheets of charge, which are not necessarily planar, produce localised excursions of electric potential, resulting in a relatively strong electric field between the layers and weaker but more extensive compensating fields outside, which restore the global potential. Ions and electrons within the double layer are accelerated, decelerated, or deflected by the electric field, depending on their direction of motion.
Double layers can be created in discharge tubes, where sustained energy is provided within the layer for electron acceleration by an external power source. Double layers are claimed to have been observed in the aurora and are invoked in astrophysical applications. Similarly, a double layer in the auroral region requires some external driver to produce electron acceleration.
Electrostatic double layers are especially common in current-carrying plasmas, and are very thin (typically tens of Debye lengths), compared to the sizes of the plasmas that contain them. Other names for a double layer are electrostatic double layer, electric double layer, plasma double layers. The term ‘electrostatic shock’ in the magnetosphere has been applied to electric fields oriented at an oblique angle to the magnetic field in such a way that the perpendicular electric field is much stronger than the parallel electric field, In laser physics, a double layer is sometimes called an ambipolar electric field.
Double layers are conceptually related to the concept of a 'sheath' (see Debye sheath). An early review of double layers from laboratory experiment and simulations is provided by Torvén.
Classification
Double layers may be classified in the following ways:
Weak and strong double layers. The strength of a double layer is expressed as the ratio of the potential drop in comparison with the plasma's equivalent thermal energy, or in comparison with the rest mass ener |
https://en.wikipedia.org/wiki/Interface%20and%20colloid%20science | Interface and colloid science is an interdisciplinary intersection of branches of chemistry, physics, nanoscience and other fields dealing with colloids, heterogeneous systems consisting of a mechanical mixture of particles between 1 nm and 1000 nm dispersed in a continuous medium. A colloidal solution is a heterogeneous mixture in which the particle size of the substance is intermediate between a true solution and a suspension, i.e. between 1–1000 nm. Smoke from a fire is an example of a colloidal system in which tiny particles of solid float in air. Just like true solutions, colloidal particles are small and cannot be seen by the naked eye. They easily pass through filter paper. But colloidal particles are big enough to be blocked by parchment paper or animal membrane.
Interface and colloid science has applications and ramifications in the chemical industry, pharmaceuticals, biotechnology, ceramics, minerals, nanotechnology, and microfluidics, among others.
There are many books dedicated to this scientific discipline, and there is a glossary of terms, Nomenclature in Dispersion Science and Technology, published by the US National Institute of Standards and Technology.
See also
Interface (matter)
Electrokinetic phenomena
Surface science |
https://en.wikipedia.org/wiki/Spectral%20clustering | In multivariate statistics, spectral clustering techniques make use of the spectrum (eigenvalues) of the similarity matrix of the data to perform dimensionality reduction before clustering in fewer dimensions. The similarity matrix is provided as an input and consists of a quantitative assessment of the relative similarity of each pair of points in the dataset.
In application to image segmentation, spectral clustering is known as segmentation-based object categorization.
Definitions
Given an enumerated set of data points, the similarity matrix may be defined as a symmetric matrix , where represents a measure of the similarity between data points with indices and . The general approach to spectral clustering is to use a standard clustering method (there are many such methods, k-means is discussed below) on relevant eigenvectors of a Laplacian matrix of . There are many different ways to define a Laplacian which have different mathematical interpretations, and so the clustering will also have different interpretations. The eigenvectors that are relevant are the ones that correspond to smallest several eigenvalues of the Laplacian except for the smallest eigenvalue which will have a value of 0. For computational efficiency, these eigenvectors are often computed as the eigenvectors corresponding to the largest several eigenvalues of a function of the Laplacian.
Laplacian matrix
Spectral clustering is well known to relate to partitioning of a mass-spring system, where each mass is associated with a data point and each spring stiffness corresponds to a weight of an edge describing a similarity of the two related data points, as in the spring system. Specifically, the classical reference explains that the eigenvalue problem describing transversal vibration modes of a mass-spring system is exactly the same as the eigenvalue problem for the graph Laplacian matrix defined as
,
where is the diagonal matrix
and A is the adjacency matrix.
The masses that are tight |
https://en.wikipedia.org/wiki/Rewrite%20%28programming%29 | A rewrite in computer programming is the act or result of re-implementing a large portion of existing functionality without re-use of its source code. When the rewrite uses no existing code at all, it is common to speak of a rewrite from scratch.
Motivations
A piece of software is typically rewritten when one or more of the following apply:
its source code is not available or is only available under an incompatible license
its code cannot be adapted to a new target platform
its existing code has become too difficult to handle and extend
the task of debugging it seems too complicated
the programmer finds it difficult to understand its source code
developers learn new techniques or wish to do a big feature overhaul which requires much change
the programming language of the source code has to be changed
Risks
Several software engineers, such as Joel Spolsky have warned against total rewrites, especially under schedule constraints or competitive pressures. While developers may initially welcome the chance to correct historical design mistakes, a rewrite also discards those parts of the design that work as required. A rewrite commits the development team to deliver not just new features, but all those that exist in the previous code, while potentially introducing new bugs or regressions of previously fixed bugs. A rewrite also interferes with the tracking of unfixed bugs in the old version.
The incremental rewrite is an alternative approach, in which developers gradually replace the existing code with calls into a new implementation, expanding that implementation until it fully replaces the old one. This approach avoids a broad loss of functionality during the rewrite. Cleanroom software engineering is another approach, which requires the team to work from an exhaustive written specification of the software's functionality, without access to its code.
Examples
Netscape's project to improve HTML layout in Navigator 4 has been cited as an example of a failed rewrite. T |
https://en.wikipedia.org/wiki/Kinetic%20proofreading | Kinetic proofreading (or kinetic amplification) is a mechanism for error correction in biochemical reactions, proposed independently by John Hopfield (1974) and Jacques Ninio (1975). Kinetic proofreading allows enzymes to discriminate between two possible reaction pathways leading to correct or incorrect products with an accuracy higher than what one would predict based on the difference in the activation energy between these two pathways.
Increased specificity is obtained by introducing an irreversible step exiting the pathway, with reaction intermediates leading to incorrect products more likely to prematurely exit the pathway than reaction intermediates leading to the correct product. If the exit step is fast relative to the next step in the pathway, the specificity can be increased by a factor of up to the ratio between the two exit rate constants. (If the next step is fast relative to the exit step, specificity will not be increased because there will not be enough time for exit to occur.) This can be repeated more than once to increase specificity further.
Specificity paradox
In protein synthesis, the error rate is on the order of . This means that when a ribosome is matching anticodons of tRNA to the codons of mRNA, it matches complementary sequences correctly nearly all the time. Hopfield noted that because of how similar the substrates are (the difference between a wrong codon and a right codon can be as small as a difference in a single base), an error rate that small is unachievable with a one-step mechanism. Both wrong and right tRNA can bind to the ribosome, and if the ribosome can only discriminate between them by complementary matching of the anticodon, it must rely on the small free energy difference between binding three matched complementary bases or only two.
A one-shot machine which tests whether the codons match or not by examining whether the codon and anticodon are bound will not be able to tell the difference between wrong and right codon |
https://en.wikipedia.org/wiki/Integration%20by%20parts%20operator | In mathematics, an integration by parts operator is a linear operator used to formulate integration by parts formulae; the most interesting examples of integration by parts operators occur in infinite-dimensional settings and find uses in stochastic analysis and its applications.
Definition
Let E be a Banach space such that both E and its continuous dual space E∗ are separable spaces; let μ be a Borel measure on E. Let S be any (fixed) subset of the class of functions defined on E. A linear operator A : S → L2(E, μ; R) is said to be an integration by parts operator for μ if
for every C1 function φ : E → R and all h ∈ S for which either side of the above equality makes sense. In the above, Dφ(x) denotes the Fréchet derivative of φ at x.
Examples
Consider an abstract Wiener space i : H → E with abstract Wiener measure γ. Take S to be the set of all C1 functions from E into E∗; E∗ can be thought of as a subspace of E in view of the inclusions
For h ∈ S, define Ah by
This operator A is an integration by parts operator, also known as the divergence operator; a proof can be found in Elworthy (1974).
The classical Wiener space C0 of continuous paths in Rn starting at zero and defined on the unit interval [0, 1] has another integration by parts operator. Let S be the collection
i.e., all bounded, adapted processes with absolutely continuous sample paths. Let φ : C0 → R be any C1 function such that both φ and Dφ are bounded. For h ∈ S and λ ∈ R, the Girsanov theorem implies that
Differentiating with respect to λ and setting λ = 0 gives
where (Ah)(x) is the Itō integral
The same relation holds for more general φ by an approximation argument; thus, the Itō integral is an integration by parts operator and can be seen as an infinite-dimensional divergence operator. This is the same result as the integration by parts formula derived from the Clark-Ocone theorem. |
https://en.wikipedia.org/wiki/Frozen%20vegetables | Frozen vegetables are vegetables that have had their temperature reduced and maintained to below their freezing point for the purpose of storage and transportation (often for far longer than their natural shelf life would permit) until they are ready to be eaten. They may be commercially packaged or frozen at home. A wide range of frozen vegetables are sold in supermarkets.
Examples of frozen vegetables which can be found in supermarkets include spinach, broccoli, cauliflower, peas, sweetcorn, yam (in Asia) either packaged as a single ingredient or as mixtures. There are occasions when frozen vegetables are mixed with other food types, such as pasta or cheese. Frozen fruits are produced using a very similar approach.
Some popular brands include Birds Eye, Sunbulah and Green Giant, as well as supermarkets' 'store brand' items.
Frozen vegetables have some advantages over fresh ones, in that they are available when the fresh counterpart is out-of-season, they have a very long shelf life when kept in a freezer and that they often have been processed a step or more closer to eating (usually washed and cut, sometimes also seasoned). In many cases, they may be more economical to purchase than their fresh counterparts or are packaged while ripe. The fruit used for frozen fruit is overripe. Some use the terminology "spoiled" or "seconds".
The history of frozen fruits can date back to the Liao Dynasty of China, with the "frozen" pear being a classic delicacy eaten by the Khitan tribes in the Northeastern region of China. Modern frozen vegetables with the flash freezing technique was popularized by Clarence Birdseye in 1929.
Nutrition
In general, boiling vegetables can cause them to lose vitamins. Thus, the process of blanching does have deleterious effects on some nutrients. In particular, vitamin C and folic acid are susceptible to loss during the commercial process. In addition, studies have shown that thawing frozen vegetables before cooking can accelerate the lo |
https://en.wikipedia.org/wiki/Pacific%E2%80%93North%20American%20teleconnection%20pattern | The Pacific–North American teleconnection pattern (PNA) is a climatological term for a large-scale weather pattern with two modes, denoted positive and negative, and which relates the atmospheric circulation pattern over the North Pacific Ocean with the one over the North American continent.
The positive phase of the PNA pattern features above-average barometric pressure heights in the vicinity of Hawaii and over the inter-mountain region of North America, and below-average heights located south of the Aleutian Islands and over the southeastern United States. The PNA pattern is associated with strong fluctuations in the strength and location of the East Asian jet stream. The positive phase is associated with an enhanced East Asian jet stream and with an eastward shift in the jet exit region toward the western United States. The negative phase is associated with a westward retraction of that jet stream toward eastern Asia, blocking activity over the high latitudes of the North Pacific, and a strong split-flow configuration over the central North Pacific.
The positive phase of the PNA pattern is associated with above-average temperatures over western Canada and the extreme western United States, and below-average temperatures across the south-central and southeastern US. The PNA tends to have little impact on surface temperature variability over North America during summer. The associated precipitation anomalies include above-average totals in the Gulf of Alaska extending into the Pacific Northwestern United States, and below-average totals over the upper Midwestern United States.
The negative PNA phase is associated with the opposite.
Although the PNA pattern is a natural internal mode of climate variability, it is also strongly influenced by the El Niño-Southern Oscillation (ENSO) phenomenon. The positive phase of the PNA pattern tends to be associated with Pacific warm episodes (El Niño), and the negative phase tends to be associated with Pacific cold episodes |
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