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https://en.wikipedia.org/wiki/Oxidative%20stress | Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage. Disturbances in the normal redox state of cells can cause toxic effects through the production of peroxides and free radicals that damage all components of the cell, including proteins, lipids, and DNA. Oxidative stress from oxidative metabolism causes base damage, as well as strand breaks in DNA. Base damage is mostly indirect and caused by the reactive oxygen species generated, e.g., O2− (superoxide radical), OH (hydroxyl radical) and H2O2 (hydrogen peroxide). Further, some reactive oxidative species act as cellular messengers in redox signaling. Thus, oxidative stress can cause disruptions in normal mechanisms of cellular signaling.
In humans, oxidative stress is thought to be involved in the development of attention deficit hyperactivity disorder, cancer, Parkinson's disease, Lafora disease, Alzheimer's disease, atherosclerosis, heart failure, myocardial infarction, fragile X syndrome, sickle-cell disease, lichen planus, vitiligo, autism, infection, chronic fatigue syndrome, and depression; however, reactive oxygen species can be beneficial, as they are used by the immune system as a way to attack and kill pathogens. Short-term oxidative stress may also be important in prevention of aging by induction of a process named mitohormesis, and is required to initiate stress response processes in plants.
Chemical and biological effects
Chemically, oxidative stress is associated with increased production of oxidizing species or a significant decrease in the effectiveness of antioxidant defenses, such as glutathione. The effects of oxidative stress depend upon the size of these changes, with a cell being able to overcome small perturbations and regain its original state. However, more severe oxidative stress can cause cell death, and even moderate oxidati |
https://en.wikipedia.org/wiki/SipXecs | SipXecs is a free software enterprise communications system. It was initially developed by Pingtel Corporation in 2003 as a voice over IP telephony server located in Boston, MA. The server was later extended with additional collaboration capabilities as part of the SIPfoundry project. Since its extension, sipXecs now acts as a software implementation of the Session Initiation Protocol (SIP), making it a full IP-based communications system.
SipXecs competitors include other open-source telephony and SoftSwitch solutions such as Asterisk, FreeSWITCH, and the SIP Express Router.
History
Development of sipXecs began in 2003 by Pingtel Corporation. In 2004, Pingtel adopted an open-source business model and contributed the codebase to the not-for-profit organization SIPfoundry. It has been an open source project since then.
Pingtel's assets were acquired by Bluesocket in July 2007. In August 2008 the Pingtel assets were acquired from Bluesocket by Nortel. Subsequent to the acquisition by Nortel, Nortel released the SCS500 product based on sipXecs. SCS500 was positioned as an open and software-only telephony server for the SMB market up to 500 users and received some recognition. It was later renamed SCS and positioned as an enterprise communications system.
Subsequent to the Nortel bankruptcy and the acquisition of the Nortel assets by Avaya, sipXecs continued to be used as the basis for the Avaya Live cloud based communications service.
In April 2010 the founders of SIPfoundry founded , a commercial version of the software.
Information
SipXecs is designed as a software-only, distributed cloud application. It runs on the Linux operating system CentOS or RHEL on either virtualized or physical servers. A minimum configuration allows running all of the sipXecs components on a single server, including database, all available services, and the sipXecs management. Global clusters can be built using built-in auto-configuration capabilities from the centralized management |
https://en.wikipedia.org/wiki/Rat%20Genome%20Database | The Rat Genome Database (RGD) is a database of rat genomics, genetics, physiology and functional data, as well as data for comparative genomics between rat, human and mouse. RGD is responsible for attaching biological information to the rat genome via structured vocabulary, or ontology, annotations assigned to genes and quantitative trait loci (QTL), and for consolidating rat strain data and making it available to the research community. They are also developing a suite of tools for mining and analyzing genomic, physiologic and functional data for the rat, and comparative data for rat, mouse, human, and five other species.
RGD began as a collaborative effort between research institutions involved in rat genetic and genomic research. Its goal, as stated in the National Institutes of Health’s Request for Grant Application: HL-99-013, is the establishment of a Rat Genome Database to collect, consolidate, and integrate data generated from ongoing rat genetic and genomic research efforts and make this data widely available to the scientific community. A secondary, but critical goal is to provide curation of mapped positions for quantitative trait loci, known mutations and other phenotypic data.
The rat continues to be extensively used by researchers as a model organism for investigating pharmacology, toxicology, general physiology and the biology and pathophysiology of disease. In recent years, there has been a rapid increase in rat genetic and genomic data. In addition to this, the Rat Genome Database has become a central point for information on the rat for research and now features information on not just genetics and genomics, but physiology and molecular biology as well. There are tools and data pages available for all of these fields that are curated by RGD staff.
Data
RGD’s data consists of manual annotations from RGD researchers as well as imported annotations from a variety of different sources. RGD also exports their own annotations to share with others.
|
https://en.wikipedia.org/wiki/Hypoxic%20pulmonary%20vasoconstriction | Hypoxic pulmonary vasoconstriction (HPV), also known as the Euler-Liljestrand mechanism, is a physiological phenomenon in which small pulmonary arteries constrict in the presence of alveolar hypoxia (low oxygen levels). By redirecting blood flow from poorly-ventilated lung regions to well-ventilated lung regions, HPV is thought to be the primary mechanism underlying ventilation/perfusion matching.
The process might initially seem counterintuitive, as low oxygen levels might theoretically stimulate increased blood flow to the lungs to increase gas exchange. However, the purpose of HPV is to distribute bloodflow regionally to increase the overall efficiency of gas exchange between air and blood. While the maintenance of ventilation/perfusion ratio during regional obstruction of airflow is beneficial, HPV can be detrimental during global alveolar hypoxia which occurs with exposure to high altitude, where HPV causes a significant increase in total pulmonary vascular resistance, and pulmonary arterial pressure, potentially leading to pulmonary hypertension and pulmonary edema.
Several factors inhibit HPV including increased cardiac output, hypocapnia, hypothermia, acidosis/alkalosis, increased pulmonary vascular resistance, inhaled anesthetics, calcium channel blockers, positive end-expiratory pressure (PEEP), high-frequency ventilation (HFV), isoproterenol, nitric oxide, and vasodilators.
Molecular mechanism
The classical explanation of HPV involves inhibition of hypoxia-sensitive voltage-gated potassium channels in pulmonary artery smooth muscle cells leading to depolarization. This depolarization activates voltage-dependent calcium channels, which increases intracellular calcium and activates smooth muscle contractile machinery which in turn causes vasoconstriction. However, later studies have reported additional ion channels and mechanisms that contribute to HPV, such as transient receptor potential canonical 6 (TRPC6) channels, and transient receptor potential va |
https://en.wikipedia.org/wiki/Pascal%27s%20simplex | In mathematics, Pascal's simplex is a generalisation of Pascal's triangle into arbitrary number of dimensions, based on the multinomial theorem.
Generic Pascal's m-simplex
Let m (m > 0) be a number of terms of a polynomial and n (n ≥ 0) be a power the polynomial is raised to.
Let denote a Pascal's m-simplex. Each Pascal's m-simplex is a semi-infinite object, which consists of an infinite series of its components.
Let denote its nth component, itself a finite (m − 1)-simplex with the edge length n, with a notational equivalent .
nth component
consists of the coefficients of multinomial expansion of a polynomial with m terms raised to the power of n:
where .
Example for
Pascal's 4-simplex , sliced along the k4. All points of the same color belong to the same n-th component, from red (for n = 0) to blue (for n = 3).
Specific Pascal's simplices
Pascal's 1-simplex
is not known by any special name.
nth component
(a point) is the coefficient of multinomial expansion of a polynomial with 1 term raised to the power of n:
Arrangement of
which equals 1 for all n.
Pascal's 2-simplex
is known as Pascal's triangle .
nth component
(a line) consists of the coefficients of binomial expansion of a polynomial with 2 terms raised to the power of n:
Arrangement of
Pascal's 3-simplex
is known as Pascal's tetrahedron .
nth component
(a triangle) consists of the coefficients of trinomial expansion of a polynomial with 3 terms raised to the power of n:
Arrangement of
Properties
Inheritance of components
is numerically equal to each (m − 1)-face (there is m + 1 of them) of , or:
From this follows, that the whole is (m + 1)-times included in , or:
Example
For more terms in the above array refer to
Equality of sub-faces
Conversely, is (m + 1)-times bounded by , or:
From this follows, that for given n, all i-faces are numerically equal in nth components of all Pascal's (m > i)-simplices, or:
Example
The 3rd component (2-simplex) of Pascal's 3 |
https://en.wikipedia.org/wiki/Integer%20overflow | In computer programming, an integer overflow occurs when an arithmetic operation attempts to create a numeric value that is outside of the range that can be represented with a given number of digits – either higher than the maximum or lower than the minimum representable value.
The most common result of an overflow is that the least significant representable digits of the result are stored; the result is said to wrap around the maximum (i.e. modulo a power of the radix, usually two in modern computers, but sometimes ten or another radix).
An overflow condition may give results leading to unintended behavior. In particular, if the possibility has not been anticipated, overflow can compromise a program's reliability and security.
For some applications, such as timers and clocks, wrapping on overflow can be desirable. The C11 standard states that for unsigned integers, modulo wrapping is the defined behavior and the term overflow never applies: "a computation involving unsigned operands can never overflow."
On some processors like graphics processing units (GPUs) and digital signal processors (DSPs) which support saturation arithmetic, overflowed results would be "clamped", i.e. set to the minimum or the maximum value in the representable range, rather than wrapped around.
Origin
The register width of a processor determines the range of values that can be represented in its registers. Though the vast majority of computers can perform multiple-precision arithmetic on operands in memory, allowing numbers to be arbitrarily long and overflow to be avoided, the register width limits the sizes of numbers that can be operated on (e.g., added or subtracted) using a single instruction per operation. Typical binary register widths for unsigned integers include:
4-bit: maximum representable value 24 − 1 = 15
8-bit: maximum representable value 28 − 1 = 255
16-bit: maximum representable value 216 − 1 = 65,535
32-bit: maximum representable value 232 − 1 = 4,294,967,295 (th |
https://en.wikipedia.org/wiki/Wave%20tank | A wave tank is a laboratory setup for observing the behavior of surface waves. The typical wave tank is a box filled with liquid, usually water, leaving open or air-filled space on top. At one end of the tank, an actuator generates waves; the other end usually has a wave-absorbing surface. A similar device is the ripple tank, which is flat and shallow and used for observing patterns of surface waves from above.
Wave basin
A wave basin is a wave tank which has a width and length of comparable magnitude, often used for testing ships, offshore structures and three-dimensional models of harbors (and their breakwaters).
Wave flume
A wave flume (or wave channel) is a special sort of wave tank: the width of the flume is much less than its length. The generated waves are therefore – more or less – two-dimensional in a vertical plane (2DV), meaning that the orbital flow velocity component in the direction perpendicular to the flume side wall is much smaller than the other two components of the three-dimensional velocity vector. This makes a wave flume a well-suited facility to study near-2DV structures, like cross-sections of a breakwater. Also (3D) constructions providing little blockage to the flow may be tested, e.g. measuring wave forces on vertical cylinders with a diameter much less than the flume width.
Wave flumes may be used to study the effects of water waves on coastal structures, offshore structures, sediment transport and other transport phenomena.
The waves are most often generated with a mechanical wavemaker, although there are also wind–wave flumes with (additional) wave generation by an air flow over the water – with the flume closed above by a roof above the free surface. The wavemaker frequently consists of a translating or rotating rigid wave board. Modern wavemakers are computer controlled, and can generate besides periodic waves also random waves, solitary waves, wave groups or even tsunami-like wave motion. The wavemaker is at one end of the w |
https://en.wikipedia.org/wiki/Subfunctor | In category theory, a branch of mathematics, a subfunctor is a special type of functor that is an analogue of a subset.
Definition
Let C be a category, and let F be a contravariant functor from C to the category of sets Set. A contravariant functor G from C to Set is a subfunctor of F if
For all objects c of C, G(c) ⊆ F(c), and
For all arrows f: → c of C, G(f) is the restriction of F(f) to G(c).
This relation is often written as G ⊆ F.
For example, let 1 be the category with a single object and a single arrow. A functor F: 1 → Set maps the unique object of 1 to some set S and the unique identity arrow of 1 to the identity function 1S on S. A subfunctor G of F maps the unique object of 1 to a subset T of S and maps the unique identity arrow to the identity function 1T on T. Notice that 1T is the restriction of 1S to T. Consequently, subfunctors of F correspond to subsets of S.
Remarks
Subfunctors in general are like global versions of subsets. For example, if one imagines the objects of some category C to be analogous to the open sets of a topological space, then a contravariant functor from C to the category of sets gives a set-valued presheaf on C, that is, it associates sets to the objects of C in a way that is compatible with the arrows of C. A subfunctor then associates a subset to each set, again in a compatible way.
The most important examples of subfunctors are subfunctors of the Hom functor. Let c be an object of the category C, and consider the functor . This functor takes an object of C and gives back all of the morphisms → c. A subfunctor of gives back only some of the morphisms. Such a subfunctor is called a sieve, and it is usually used when defining Grothendieck topologies.
Open subfunctors
Subfunctors are also used in the construction of representable functors on the category of ringed spaces. Let F be a contravariant functor from the category of ringed spaces to the category of sets, and let G ⊆ F. Suppose that this inclusion |
https://en.wikipedia.org/wiki/Mott%20problem | The Mott problem is an iconic challenge to quantum mechanics theory: how can the prediction of spherically symmetric wave function result in linear tracks seen in a cloud chamber. The problem was first formulated in 1927 by Albert Einstein and Max Born and solved in 1929 by Nevill Francis Mott Mott's solution notably only uses the wave equation, not wavefunction collapse, and it is considered the earliest example of what is now called decoherence theory.
Spherical waves, particle tracks
The problem later associated with Mott concerns a spherical wave function associated with an alpha ray emitted from the decay of a radioactive atomic nucleus. Intuitively, one might think that such a wave function should randomly ionize atoms throughout the cloud chamber, but this is not the case. The result of such a decay is always observed as linear tracks seen in Wilson's cloud chamber. The origin of the tracks given the original spherical wave predicted by theory is the problem requiring physical explanation.
In practice, virtually all high energy physics experiments, such as those conducted at particle colliders, involve wave functions which are inherently spherical. Yet, when the results of a particle collision are detected, they are invariably in the form of linear tracks (see, for example, the illustrations accompanying the article on bubble chambers). It is somewhat strange to think that a spherically symmetric wave function should be observed as a straight track, and yet, this occurs on a daily basis in all particle collider experiments.
History
The problem of alpha particle track was discussed at the Fifth Solvay conference in 1927. Max Born described the problem as one that Albert Einstein pointed to, asking "how can the corpuscular character of the phenomenon be reconciled here with the representation by waves?". Born answers with Heisenberg's "reduction of the probability packet", now called wavefunction collapse, introduced in May of 1927. Born says each droplet |
https://en.wikipedia.org/wiki/FreeRTOS | FreeRTOS is a real-time operating system kernel for embedded devices that has been ported to 35 microcontroller platforms. It is distributed under the MIT License.
History
The FreeRTOS kernel was originally developed by Richard Barry around 2003, and was later developed and maintained by Barry's company, Real Time Engineers Ltd. In 2017, the firm passed stewardship of the FreeRTOS project to Amazon Web Services (AWS). Barry continues to work on FreeRTOS as part of an AWS team.
Implementation
FreeRTOS is designed to be small and simple. It is mostly written in the C programming language to make it easy to port and maintain. It also comprises a few assembly language functions where needed, mostly in architecture-specific scheduler routines.
Process management
FreeRTOS provides methods for multiple threads or tasks, mutexes, semaphores and software timers. A tickless mode is provided for low power applications. Thread priorities are supported. FreeRTOS applications can be statically allocated, but objects can also be dynamically allocated with five schemes of memory management (allocation):
allocate only;
allocate and free with a very simple, fast, algorithm;
a more complex but fast allocate and free algorithm with memory coalescence;
an alternative to the more complex scheme that includes memory coalescence that allows a heap to be broken across multiple memory areas.
and C library allocate and free with some mutual exclusion protection.
RTOSes typically do not have the more advanced features that are found in operating systems like Linux and Microsoft Windows, such as device drivers, advanced memory management, and user accounts. The emphasis is on compactness and speed of execution. FreeRTOS can be thought of as a thread library rather than an operating system, although command line interface and POSIX-like input/output (I/O) abstraction are available.
FreeRTOS implements multiple threads by having the host program call a thread tick method at regular sho |
https://en.wikipedia.org/wiki/Zero-knowledge%20password%20proof | In cryptography, a zero-knowledge password proof (ZKPP) is a type of zero-knowledge proof that allows one party (the prover) to prove to another party (the verifier) that it knows a value of a password, without revealing anything other than the fact that it knows the password to the verifier. The term is defined in IEEE P1363.2, in reference to one of the benefits of using a password-authenticated key exchange (PAKE) protocol that is secure against off-line dictionary attacks. A ZKPP prevents any party from verifying guesses for the password without interacting with a party that knows it and, in the optimal case, provides exactly one guess in each interaction.
A common use of a zero-knowledge password proof is in authentication systems where one party wants to prove its identity to a second party using a password but doesn't want the second party or anybody else to learn anything about the password. For example, apps can validate a password without processing it and a payment app can check the balance of an account without touching or learning anything about the amount.
History
The first methods to demonstrate a ZKPP were the encrypted key exchange methods (EKE) described by Steven M. Bellovin and Michael Merritt in 1992. A considerable number of refinements, alternatives, and variations in the growing class of password-authenticated key agreement methods were developed in subsequent years. Standards for these methods include IETF , IEEE P1363.2, and ISO-IEC 11770-4.
See also
Cryptographic protocol
Outline of cryptography
Key-agreement protocol
Secure Remote Password protocol |
https://en.wikipedia.org/wiki/Antiisomorphism | In category theory, a branch of mathematics, an antiisomorphism (or anti-isomorphism) between structured sets A and B is an isomorphism from A to the opposite of B (or equivalently from the opposite of A to B). If there exists an antiisomorphism between two structures, they are said to be antiisomorphic.
Intuitively, to say that two mathematical structures are antiisomorphic is to say that they are basically opposites of one another.
The concept is particularly useful in an algebraic setting, as, for instance, when applied to rings.
Simple example
Let A be the binary relation (or directed graph) consisting of elements {1,2,3} and binary relation defined as follows:
Let B be the binary relation set consisting of elements {a,b,c} and binary relation defined as follows:
Note that the opposite of B (denoted Bop) is the same set of elements with the opposite binary relation (that is, reverse all the arcs of the directed graph):
If we replace a, b, and c with 1, 2, and 3 respectively, we see that each rule in Bop is the same as some rule in A. That is, we can define an isomorphism from A to Bop by . is then an antiisomorphism between A and B.
Ring anti-isomorphisms
Specializing the general language of category theory to the algebraic topic of rings, we have:
Let R and S be rings and f: R → S be a bijection. Then f is a ring anti-isomorphism if
If R = S then f is a ring anti-automorphism.
An example of a ring anti-automorphism is given by the conjugate mapping of quaternions:
Notes |
https://en.wikipedia.org/wiki/Disinfectant%20%28software%29 | Disinfectant was a popular antivirus software program for the classic Mac OS. It was originally released as freeware by John Norstad in the spring of 1989. Disinfectant featured a system extension that would detect virus infections and an application with which users could scan for and remove viruses. New versions of Disinfectant were subsequently released to detect additional viruses. Bob LeVitus praised and recommended Disinfectant in 1992. In May 1998, Norstad retired Disinfectant, citing the new danger posed by macro viruses, which Disinfectant did not detect, and the inability of a single individual to maintain a program that caught all of them. |
https://en.wikipedia.org/wiki/Password-authenticated%20key%20agreement | In cryptography, a password-authenticated key agreement method is an interactive method for two or more parties to establish cryptographic keys based on one or more party's knowledge of a password.
An important property is that an eavesdropper or man-in-the-middle cannot obtain enough information to be able to brute-force guess a password without further interactions with the parties for each (few) guesses. This means that strong security can be obtained using weak passwords.
Types
Password-authenticated key agreement generally encompasses methods such as:
Balanced password-authenticated key exchange
Augmented password-authenticated key exchange
Password-authenticated key retrieval
Multi-server methods
Multi-party methods
In the most stringent password-only security models, there is no requirement for the user of the method to remember any secret or public data other than the password.
Password-authenticated key exchange (PAKE) is a method in which two or more parties, based only on their knowledge of a shared password, establish a cryptographic key using an exchange of messages, such that an unauthorized party (one who controls the communication channel but does not possess the password) cannot participate in the method and is constrained as much as possible from brute-force guessing the password. (The optimal case yields exactly one guess per run exchange.) Two forms of PAKE are balanced and augmented methods.
Balanced PAKE
Balanced PAKE assumes the two parties in either a client-client or client-server situation use the same secret password to negotiate and authenticate a shared key. Examples of these are:
Encrypted Key Exchange (EKE)
PAK and PPK
SPEKE (Simple password exponential key exchange)
Elliptic Curve based Secure Remote Password protocol (EC-SRP or SRP5) There is a free Java card implementation.
Dragonfly – IEEE Std 802.11-2012, RFC 5931, RFC 6617
CPace
SPAKE1 and SPAKE2
SESPAKE – RFC 8133
J-PAKE (Password Authenticated Key Exchang |
https://en.wikipedia.org/wiki/Masahiko%20Fujiwara | Masahiko Fujiwara (Japanese: 藤原 正彦 Fujiwara Masahiko; born July 9, 1943, in Shinkyo, Manchukuo) is a Japanese mathematician and writer who is known for his book The Dignity of the Nation. He is a professor emeritus at Ochanomizu University.
Biography
Masahiko Fujiwara is the son of Jirō Nitta and Tei Fujiwara, who were both popular authors. He graduated from the University of Tokyo in 1966.
He began writing after a two-year position as associate professor at the University of Colorado, with a book Wakaki sugakusha no Amerika
designed to explain American campus life to Japanese people. He also wrote about the University of Cambridge, after a year's visit (Harukanaru Kenburijji: Ichi sugakusha no Igirisu). In a popular book on mathematics, he categorized theorems as beautiful theorems or ugly theorems. He is also known in Japan for speaking out against government reforms in secondary education. He wrote The Dignity of the Nation, which according to Time Asia was the second best selling book in the first six months of 2006 in Japan.
In 2006, Fujiwara published Yo ni mo utsukushii sugaku nyumon ("An Introduction to the World's Most Elegant Mathematics") with the writer Yōko Ogawa: it is a dialogue between novelist and mathematician on the extraordinary beauty of numbers. |
https://en.wikipedia.org/wiki/Dark%20star%20%28Newtonian%20mechanics%29 | A dark star is a theoretical object compatible with Newtonian mechanics that, due to its large mass, has a surface escape velocity that equals or exceeds the speed of light. Whether light is affected by gravity under Newtonian mechanics is unclear but if it were accelerated the same way as projectiles, any light emitted at the surface of a dark star would be trapped by the star's gravity, rendering it dark, hence the name. Dark stars are analogous to black holes in general relativity.
Dark star theory history
John Michell and dark stars
During 1783 geologist John Michell wrote a letter to Henry Cavendish outlining the expected properties of dark stars, published by The Royal Society in their 1784 volume. Michell calculated that when the escape velocity at the surface of a star was equal to or greater than lightspeed, the generated light would be gravitationally trapped so that the star would not be visible to a distant astronomer.
Michell's idea for calculating the number of such "invisible" stars anticipated 20th century astronomers' work: he suggested that since a certain proportion of double-star systems might be expected to contain at least one "dark" star, we could search for and catalogue as many double-star systems as possible, and identify cases where only a single circling star was visible. This would then provide a statistical baseline for calculating the amount of other unseen stellar matter that might exist in addition to the visible stars.
Dark stars and gravitational shifts
Michell also suggested that future astronomers might be able to identify the surface gravity of a distant star by seeing how far the star's light was shifted to the weaker end of the spectrum, a precursor of Einstein's 1911 gravity-shift argument. However, Michell cited Newton as saying that blue light was less energetic than red (Newton thought that more massive particles were associated with bigger wavelengths), so Michell's predicted spectral shifts were in the wrong directi |
https://en.wikipedia.org/wiki/Dana%20Foundation | The Dana Foundation (Charles A. Dana Foundation) is a private philanthropic organization based in New York dedicated to advancing neuroscience and society by supporting cross-disciplinary intersections such as neuroscience and ethics, law, policy, humanities, and arts.
Leadership
The foundation was founded in 1950 by Charles A. Dana, a legislator and businessman from New York State, and president of the Dana Corporation. He presided over the organization until 1960, but continued to participate until his death in 1975.
Steven E. Hyman, M.D., is chairman of the board of directors of the foundation. Caroline Montojo, Ph.D., is the current president of the foundation.
The Dana Alliance for Brain Initiatives
The Dana Foundation supported the Dana Alliance for Brain Initiatives (which included the European Dana Alliance for the Brain), a nonprofit organization of leading neuroscientists committed to advancing public awareness about the progress and promise of brain research, from 1993 to 2022.
As William Safire put it in his column retiring from The New York Times in 2005: "They [the foundation] roped me in, a dozen years ago, to help enliven a moribund 'decade of the brain.' By encouraging many of the most prestigious neuroscientists to get out of the ivory tower and explain in plain words the potential of brain science, they enlisted the growing public and private support for research."
Grant programs
In 2022, the Dana Foundation pivoted away from grants for research to grants that aim to strengthen neuroscience's positive role in the world. Current grants fall under three categories.
NextGen: To develop a new generation of interdisciplinary experts who shepherd neuroscience uses for a better world. Its current major project is creating Dana Centers for Neuroscience & Society.
Frontiers: To grow capacity for informed public reflection on emerging neuroscience and neurotechnology. Its projects include Judicial Seminars on Emerging Issues in Neuroscience, whi |
https://en.wikipedia.org/wiki/Reflector%20%28antenna%29 | An antenna reflector is a device that reflects electromagnetic waves. Antenna reflectors can exist as a standalone device for redirecting radio frequency (RF) energy, or can be integrated as part of an antenna assembly.
Standalone reflectors
The function of a standalone reflector is to redirect electromagnetic (EM) energy, generally in the radio wavelength range of the electromagnetic spectrum.
Common standalone reflector types are
corner reflector, which reflects the incoming signal back to the direction from which it came, commonly used in radar.
flat reflector, which reflects the signal such as a mirror and is often used as a passive repeater.
Integrated reflectors
When integrated into an antenna assembly, the reflector serves to modify the radiation pattern of the antenna, increasing gain in a given direction.
Common integrated reflector types are
parabolic reflector, which focuses a beam signal into one point or directs a radiating signal into a beam.
a passive element slightly longer than and located behind a radiating dipole element that absorbs and re-radiates the signal in a directional way as in a Yagi antenna array.
a flat reflector such as used in a Short backfire antenna or Sector antenna.
a corner reflector used in UHF television antennas.
a cylindrical reflector as used in Cantenna.
Design criteria
Parameters that can directly influence the performance of an antenna with integrated reflector:
Dimensions of the reflector (Big ugly dish versus small dish)
Spillover (part of the feed antenna radiation misses the reflector)
Aperture blockage (also known as feed blockage: part of the feed energy is reflected back into the feed antenna and does not contribute to the main beam)
Illumination taper (feed illumination reduced at the edges of the reflector)
Reflector surface deviation
Defocusing
Cross polarization
Feed losses
Antenna feed mismatch
Non-uniform amplitude/phase distributions
The antenna efficiency is measured in terms of it |
https://en.wikipedia.org/wiki/Double%20minute | Double minutes are small fragments of extrachromosomal DNA, which have been observed in a large number of human tumors including breast, lung, ovary, colon, and most notably, neuroblastoma. They are a manifestation of gene amplification as a result of chromothripsis, during the development of tumors, which give the cells selective advantages for growth and survival. This selective advantage is as a result of double minutes frequently harboring amplified oncogenes and genes involved in drug resistance. DMs, like actual chromosomes, are composed of chromatin and replicate in the nucleus of the cell during cell division. Unlike typical chromosomes, they are composed of circular fragments of DNA, up to only a few million base pairs in size, and contain no centromere or telomere. Further to this, they often lack key regulatory elements, allowing genes to be constitutively expressed. The term ecDNA may be used to refer to DMs in a more general manner.
Formation
The most commonly proposed mechanism for DM formation is through chromothripsis, where up to hundreds of genomic arrangements occur in a single catastrophic event, and chromosome fragments which are not reintegrated join to create DMs. Specific models of DM formation other than chromothripsis have also been suggested. In the “deletion-plus-episome” model, also known as the “episome model,” DNA segments are excised from an intact chromosome, circularized, then amplified as DMs by mutual recombination. The “translocation-excision-deletion-amplification” model supports that during a translocation event, DMs are formed from the breakpoint region, in the process deleting the genes that are amplified from the chromosome. Another suggested mechanism is a multi-step evolutionary process, shown in the GLC1 cell line, in which a series of chromosomal mutation events within amplicons create subpopulations of DMs. Aside from these models, several studies suggest other processes for DM formation such as through the breakdow |
https://en.wikipedia.org/wiki/Batten%20disease | Batten disease is a fatal disease of the nervous system that typically begins in childhood. Onset of symptoms is usually between 5 and 10 years of age. Often, it is autosomal recessive. It is the common name for a group of disorders called the neuronal ceroid lipofuscinoses (NCLs).
Although Batten disease is usually regarded as the juvenile form of NCL (or "type 3"), some physicians use the term Batten disease to describe all forms of NCL. Historically, the NCLs were classified by age of disease onset as infantile NCL (INCL), late infantile NCL (LINCL), juvenile NCL (JNCL) or adult NCL (ANCL). At least 20 genes have been identified in association with Batten disease, but juvenile NCL, the most prevalent form of Batten disease, has been linked to mutations in Battenin, the protein encoded by the CLN3 gene. It was first described in 1903.
Signs and symptoms
Signs and symptoms of the disorder usually appear around ages 5–10 years, with gradual onset of vision problems or seizures. Early signs may be subtle personality and behavioral changes, slow learning or regression, repetitive speech or echolalia, clumsiness or stumbling. Slowing head growth in the infantile form, poor circulation in lower extremities (legs and feet), decreased body fat and muscle mass, curvature of the spine, hyperventilation and/or breath-holding spells, teeth grinding and constipation may occur.
Over time, affected children experience mental impairment, worsening seizures and progressive loss of sight, speech and motor skills. Batten disease is a terminal disease; life expectancy varies depending on the type or variation.
Females with juvenile Batten disease show first symptoms a year later than males, but on average die a year sooner.
Cause
NCLs are a family of diseases that are inherited in an autosomal recessive manner. Collectively referred to as Batten disease, NCLs are responsible for most paediatric neurodegenerative diseases. The specific type of NCL is characterized by the age of s |
https://en.wikipedia.org/wiki/Nanobiotechnology | Nanobiotechnology, bionanotechnology, and nanobiology are terms that refer to the intersection of nanotechnology and biology. Given that the subject is one that has only emerged very recently, bionanotechnology and nanobiotechnology serve as blanket terms for various related technologies.
This discipline helps to indicate the merger of biological research with various fields of nanotechnology. Concepts that are enhanced through nanobiology include: nanodevices (such as biological machines), nanoparticles, and nanoscale phenomena that occurs within the discipline of nanotechnology. This technical approach to biology allows scientists to imagine and create systems that can be used for biological research. Biologically inspired nanotechnology uses biological systems as the inspirations for technologies not yet created. However, as with nanotechnology and biotechnology, bionanotechnology does have many potential ethical issues associated with it.
The most important objectives that are frequently found in nanobiology involve applying nanotools to relevant medical/biological problems and refining these applications. Developing new tools, such as peptoid nanosheets, for medical and biological purposes is another primary objective in nanotechnology. New nanotools are often made by refining the applications of the nanotools that are already being used. The imaging of native biomolecules, biological membranes, and tissues is also a major topic for nanobiology researchers. Other topics concerning nanobiology include the use of cantilever array sensors and the application of nanophotonics for manipulating molecular processes in living cells.
Recently, the use of microorganisms to synthesize functional nanoparticles has been of great interest. Microorganisms can change the oxidation state of metals. These microbial processes have opened up new opportunities for us to explore novel applications, for example, the biosynthesis of metal nanomaterials. In contrast to chemical an |
https://en.wikipedia.org/wiki/Antarctic%20Adventure | is a video game developed by Konami in 1983 for the MSX, and later for video game consoles, such as NES and ColecoVision. The player takes the role of an Antarctic penguin, racing to various research stations owned by different countries in Antarctica (excluding the USSR).
The gameplay is similar to Sega's Turbo, but plays at a much slower pace, and features platform game elements. The penguin, later named Penta, must reach the next station before time runs out while avoiding sea lions and breaks in the ice. Throughout the levels, fish jump out of ice holes and can be caught for bonus points. The game, like many early video games, has no ending – when the player reaches the last station, the game starts from the first level again, but with increased difficulty.
Legacy
Antarctic Adventure was followed by a sequel for the MSX computer in 1986, entitled Penguin Adventure. In addition, the penguin character Penta, and his son Pentarou became a mascot for Konami through the 1980s. They have made appearances in over 10 games. Of particular note are his appearances in the Parodius series of shoot 'em up games.
Penta, or his son Pentarou, had appeared in Medal Games like Tsurikko Penta, Balloon Penta and Imo Hori Penta. Following in 2002 (not released for mobile in 2001), three mobile games , released on May 6, 2003, another titled , as part of Konami Taisen Colosseum, and the fishing game as Penta no Tsuri Boken, and released for i-Revo.
A screenshot from this game can briefly be seen in the introduction of Gradius ReBirth, released in 2008 for the Wii Virtual Console and in 2014 for the Wii U Virtual Console. An MSX Version was re-released for the Windows Store as part of EGG Project on November 25, 2014 in Japan.
In 1990, Konami released only in Japan a handheld electronic game of Antarctic Adventure, although it is usually listed as South Pole (a more literal translation of the Japanese title).
In 2014, Antarctic Adventure was released on a special version of the |
https://en.wikipedia.org/wiki/Dovecot%20%28software%29 | Dovecot is an open-source IMAP and POP3 server for Unix-like operating systems, written primarily with security in mind. Timo Sirainen originated Dovecot and first released it in July 2002. Dovecot developers primarily aim to produce a lightweight, fast and easy-to-set-up open-source email server.
The primary purpose of Dovecot is to act as a mail storage server. The mail is delivered to the server using some mail delivery agent (MDA) and is stored for later access with an email client (mail user agent, or MUA). Dovecot can also act as mail proxy server, forwarding connection to another mail server, or act as a lightweight MUA in order to retrieve and manipulate mail on remote server for e.g. mail migration.
According to the Open Email Survey, as of 2020, Dovecot has an installed base of at least 2.9million IMAP servers, and has a global market share of 76.9% of all IMAP servers. The results of the same survey in 2019 gave figures of 2.6million and 76.2%, respectively.
Features
Dovecot can work with standard mbox, Maildir, and its own native high-performance dbox formats. It is fully compatible with UW IMAP and Courier IMAP servers’ implementation of them, as well as mail clients accessing the mailboxes directly.
Dovecot also includes a mail delivery agent (called Local delivery agent in Dovecot's documentation) and an LMTP server, with the optional Sieve filtering support.
Dovecot supports a variety of authentication schemas for IMAP, POP and message submission agent (MSA) access, including CRAM-MD5 and the more secure DIGEST-MD5.
With version 2.2, some new features have been added to Dovecot, e.g. additional IMAP command extensions, dsync has been rewritten or optimized, and shared mailboxes now support per-user flags.
Version 2.3 adds a message submission agent, Lua scripting for authentication, and some other improvements.
Apple Inc. includes Dovecot for email services since Mac OS X Server 10.6 Snow Leopard.
In 2017, Mozilla, via the Mozilla Open Sourc |
https://en.wikipedia.org/wiki/Interior%20product | In mathematics, the interior product (also known as interior derivative, interior multiplication, inner multiplication, inner derivative, insertion operator, or inner derivation) is a degree −1 (anti)derivation on the exterior algebra of differential forms on a smooth manifold. The interior product, named in opposition to the exterior product, should not be confused with an inner product. The interior product is sometimes written as
Definition
The interior product is defined to be the contraction of a differential form with a vector field. Thus if is a vector field on the manifold then
is the map which sends a -form to the -form defined by the property that
for any vector fields
The interior product is the unique antiderivation of degree −1 on the exterior algebra such that on one-forms
where is the duality pairing between and the vector Explicitly, if is a -form and is a -form, then
The above relation says that the interior product obeys a graded Leibniz rule. An operation satisfying linearity and a Leibniz rule is called a derivation.
Properties
If in local coordinates the vector field is described by functions , then the interior product is given by
where is the form obtained by omitting from .
By antisymmetry of forms,
and so This may be compared to the exterior derivative which has the property
The interior product relates the exterior derivative and Lie derivative of differential forms by the Cartan formula (also known as the Cartan identity, Cartan homotopy formula or Cartan magic formula):
This identity defines a duality between the exterior and interior derivatives. Cartan's identity is important in symplectic geometry and general relativity: see moment map. The Cartan homotopy formula is named after Élie Cartan.
The interior product with respect to the commutator of two vector fields satisfies the identity
See also
Notes |
https://en.wikipedia.org/wiki/Adomian%20decomposition%20method | The Adomian decomposition method (ADM) is a semi-analytical method for solving ordinary and partial nonlinear differential equations. The method was developed from the 1970s to the 1990s by George Adomian, chair of the Center for Applied Mathematics at the University of Georgia.
It is further extensible to stochastic systems by using the Ito integral.
The aim of this method is towards a unified theory for the solution of partial differential equations (PDE); an aim which has been superseded by the more general theory of the homotopy analysis method.
The crucial aspect of the method is employment of the "Adomian polynomials" which allow for solution convergence of the nonlinear portion of the equation, without simply linearizing the system. These polynomials mathematically generalize to a Maclaurin series about an arbitrary external parameter; which gives the solution method more flexibility than direct Taylor series expansion.
Ordinary differential equations
Adomian method is well suited to solve Cauchy problems, an important class of problems which include initial conditions problems.
Application to a first order nonlinear system
An example of initial condition problem for an ordinary differential equation is the following:
To solve the problem, the highest degree differential operator (written here as L) is put on the left side, in the following way:
with L = d/dt and . Now the solution is assumed to be an infinite series of contributions:
Replacing in the previous expression, we obtain:
Now we identify y0 with some explicit expression on the right, and yi, i = 1, 2, 3, ..., with some expression on the right containing terms of lower order than i. For instance:
In this way, any contribution can be explicitly calculated at any order. If we settle for the four first terms, the approximant is the following:
Application to Blasius equation
A second example, with more complex boundary conditions is the Blasius equation for a flow in a boundary la |
https://en.wikipedia.org/wiki/El-Ouali%20Mustapha%20Sayed | El-Ouali Mustapha Sayed (also known as El Uali, El-Wali, Luali or Lulei; ; 1949 – 9 June 1976) was a Sahrawi nationalist leader, co-founder and second Secretary-General of the Polisario Front.
Youth and background
El-Ouali was born in 1949 in a Sahrawi nomad encampment somewhere on the hammada desert plains in eastern Spanish Sahara or northern Mauritania; some sources give his place of birth as Bir Lehlou, a location that is symbolic for the Polisario Front, for being the place of the proclamation of the Sahrawi Arab Democratic Republic (SADR). His parents were poor and his father disabled, and with the sum of the severe drought on the Sahara that year, and the consequences of the Ifni War, the family had to abandon the traditional bedouin lifestyle of the Sahrawis, settling near Tan-Tan (nowadays southern Morocco) at the late 1950s. Some sources stated that Ouali's family was deported among others to Morocco by Spanish authorities in 1960.
He went to Primary School in Tan-Tan in 1962, and then to the Islamic Institute in Taroudannt in 1966 with impressive results, being awarded scholarships to attend university in Rabat in 1970. There he studied Laws & Political sciences, and met other young members of the Sahrawi diaspora, who like him were affected by the radicalism sweeping Moroccan universities in the early 1970s (heavily influenced by May 1968 in France). He was the first alumnus in the history of Moroccan universities on achieving a punctuation of 19 out of 20 in Constitutional law. He travelled to Europe for the only time in his life about this time, visiting Amsterdam in the Netherlands & Paris in France.
El-Ouali Mustapha Sayed was associated with Ila al-Amam, a clandestine Marxist group that took a position explicitly in favour of Sahrawi self-determination.
Polisario Front
El-Ouali grew increasingly disturbed by the oppressive Spanish colonial rule over what was then known as Spanish Sahara, and although never involved with the Harakat Tahrir, news |
https://en.wikipedia.org/wiki/List%20of%20hash%20functions | This is a list of hash functions, including cyclic redundancy checks, checksum functions, and cryptographic hash functions.
Cyclic redundancy checks
Adler-32 is often mistaken for a CRC, but it is not: it is a checksum.
Checksums
Universal hash function families
Non-cryptographic hash functions
Keyed cryptographic hash functions
Unkeyed cryptographic hash functions
See also
Hash function security summary
Secure Hash Algorithms
NIST hash function competition
Key derivation functions (category) |
https://en.wikipedia.org/wiki/Mobile%20phone%20feature | A mobile phone feature is a capability, service, or application that a mobile phone offers to its users. Mobile phones are often referred to as feature phones, and offer basic telephony. Handsets with more advanced computing ability through the use of native code try to differentiate their own products by implementing additional functions to make them more attractive to consumers. This has led to great innovation in mobile phone development over the past 20 years.
The common components found on all phones are:
A number of metal–oxide–semiconductor (MOS) integrated circuit (IC) chips.
A battery (typically a lithium-ion battery), providing the power source for the phone functions.
An input mechanism to allow the user to interact with the phone. The most common input mechanism is a keypad, but touch screens are also found in smartphones.
Basic mobile phone services to allow users to make calls and send text messages.
All GSM phones use a SIM card to allow an account to be swapped among devices. Some CDMA devices also have a similar card called a R-UIM.
Individual GSM, WCDMA, IDEN and some satellite phone devices are uniquely identified by an International Mobile Equipment Identity (IMEI) number.
All mobile phones are designed to work on cellular networks and contain a standard set of services that allow phones of different types and in different countries to communicate with each other. However, they can also support other features added by various manufacturers over the years:
roaming which permits the same phone to be used in multiple countries, providing that the operators of both countries have a roaming agreement.
send and receive data and faxes (if a computer is attached), access WAP services, and provide full Internet access using technologies such as GPRS.
applications like a clock, alarm, calendar, contacts, and calculator and a few games.
Sending and receiving pictures and videos (by without internet) through MMS, and for short distances with |
https://en.wikipedia.org/wiki/Dolby%20Digital%20Plus | Dolby Digital Plus, also known as Enhanced AC-3 (and commonly abbreviated as DDP, DD+, E-AC-3 or EC-3), is a digital audio compression scheme developed by Dolby Labs for the transport and storage of multi-channel digital audio. It is a successor to Dolby Digital (AC-3), and has a number of improvements over that codec, including support for a wider range of data rates (32 kbit/s to 6144 kbit/s), an increased channel count, and multi-program support (via substreams), as well as additional tools (algorithms) for representing compressed data and counteracting artifacts. Whereas Dolby Digital (AC-3) supports up to five full-bandwidth audio channels at a maximum bitrate of 640 kbit/s, E-AC-3 supports up to 15 full-bandwidth audio channels at a maximum bitrate of 6.144 Mbit/s.
The full set of technical specifications for E-AC-3 (and AC-3) are standardized and published in Annex E of ATSC A/52:2012, as well as Annex E of ETSI TS 102 366.
Technical details
Specifications
Dolby Digital Plus is capable of the following:
Coded bitrate: 0.032 to 6.144 Mbit/s
Audio channels: 1.0 to 15.1 (i.e. from mono to 15 full range channels and a low frequency effects channel)
Number of audio programs per bitstream: 8
Sample rate: 32, 44.1 or 48 kHz
Structure
A Dolby Digital Plus service consists of one or more substreams. There are three types of substreams:
Independent substreams, which can contain a single program of up to 5.1 channels. Up to eight dependent substreams may be present in a Dolby Digital Plus stream. The channels present in an independent substream are limited to the traditional 5.1 channels: Left (L), Right (R), Center (C), Left Surround (Ls), and Right Surround (Rs) channels, as well as a Low Frequency Effects (Lfe) channel.
Legacy substreams, which contain a single 5.1 program, and which correspond directly to Dolby Digital content. At most a single legacy substream may be present in a DD+ stream.
Dependent substreams, which contain additional channels beyon |
https://en.wikipedia.org/wiki/Delay-insensitive%20minterm%20synthesis | Within digital electronics, the DIMS (delay-insensitive minterm synthesis) system is an asynchronous design methodology making the least possible timing assumptions. Assuming only the quasi-delay-insensitive delay model the generated designs need little if any timing hazard testing. The basis for DIMS is the use of two wires to represent each bit of data. This is known as a dual-rail data encoding. Parts of the system communicate using the early four-phase asynchronous protocol.
The construction of DIMS logic gates comprises generating every possible minterm using a row of C-elements and then gathering the outputs of these using OR gates which generate the true and false output signals. With two dual-rail inputs the gate would be composed of four two-input C-elements. A three input gate uses eight three-input C-elements.
Latches are constructed using two C-elements to store the data and an OR gate to acknowledge the input once the data has been latched by attaching as its inputs the data output wires. The acknowledge from the forward stage is inverted and passed to the C-elements to allow them to reset once the computation has completed. This latch design is known as the 'half latch'. Other asynchronous latches provide a higher data capacity and levels of decoupling.
DIMS designs are large and slow but they have the advantage of being very robust.
Further reading
Jens Sparsø, Steve Furber: "Principles of Asynchronous Circuit Design"; Kluwer, Dordrecht (2001); chapter 5.5.1.
Digital electronics |
https://en.wikipedia.org/wiki/Common%20Algebraic%20Specification%20Language | The Common Algebraic Specification Language (CASL) is a general-purpose specification language based on first-order logic with induction. Partial functions and subsorting are also supported.
Overview
CASL has been designed by CoFI, the Common Framework Initiative (CoFI), with the aim to subsume many existing specification languages.
CASL comprises four levels:
basic specifications, for the specification of single software modules,
structured specifications, for the modular specification of modules,
architectural specifications, for the prescription of the structure of implementations,
specification libraries, for storing specifications distributed over the Internet.
The four levels are orthogonal to each other. In particular, it is possible to use CASL structured and architectural specifications and libraries with logics other than CASL. For this purpose, the logic has to be formalized as an institution. This feature is also used by the CASL extensions.
Extensions
Several extensions of CASL have been designed:
HasCASL, a higher-order extension
CoCASL, a coalgebraic extension
CspCASL, a concurrent extension based on CSP
ModalCASL, a modal logic extension
CASL-LTL, a temporal logic extension
HetCASL, an extension for heterogeneous specification
External links
Official CoFI website
CASL
The heterogeneous tool set Hets, the main analysis tool for CASL
Formal specification languages |
https://en.wikipedia.org/wiki/Institution%20%28computer%20science%29 | The notion of institution was created by Joseph Goguen and Rod Burstall in the late 1970s, in order to deal with the "population explosion among the logical systems used in computer science". The notion attempts to "formalize the informal" concept of logical system.
The use of institutions makes it possible to develop concepts of specification languages (like structuring of specifications, parameterization, implementation, refinement, and development), proof calculi, and even tools in a way completely independent of the underlying logical system. There are also morphisms that allow to relate and translate logical systems. Important applications of this are re-use of logical structure (also called borrowing), and heterogeneous specification and combination of logics.
The spread of institutional model theory has generalized various notions and results of model theory, and institutions themselves have impacted the progress of universal logic.
Definition
The theory of institutions does not assume anything about the nature of the logical system. That is, models and sentences may be arbitrary objects; the only assumption is that there is a satisfaction relation between models and sentences, telling whether a sentence holds in a model or not. Satisfaction is inspired by Tarski's truth definition, but can in fact be any binary relation.
A crucial feature of institutions is that models, sentences, and their satisfaction, are always considered to live in some vocabulary or context (called signature) that defines the (non-logic) symbols that may be used in sentences and that need to be interpreted in models. Moreover, signature morphisms allow to extend signatures, change notation, and so on. Nothing is assumed about signatures and signature morphisms except that signature morphisms can be composed; this amounts to having a
category of signatures and morphisms. Finally, it is assumed that signature morphisms lead to translations of sentences and models in a way that sati |
https://en.wikipedia.org/wiki/MARID | MARID was an IETF working group in the applications area tasked to propose standards for email authentication in 2004. The name is an acronym of MTA Authorization Records In DNS.
Background
Lightweight MTA Authentication Protocol (LMAP) was a generic name for a set of 'designated sender' proposals that were discussed in the ASRG in the Fall of 2003, including:
Designated Mailers Protocol (DMP)
Designated Relays Inquiry Protocol (DRIP)
Flexible Sender Validation (FSV)
MTAMARK
Reverse MX (RMX)
Sender Policy Framework (SPF)
These schemes attempt to list the valid IP addresses that can send mail for a domain. The "lightweight" in LMAP essentially stands for "no crypto", as opposed to DomainKeys and its successor, DKIM. In March 2004, the Internet Engineering Task Force IETF held a BoF on these proposals. As the result of that meeting, the task force chartered the MARID working group.
Controversy
Microsoft's Caller-ID proposal was a late and highly controversial addition to this mix. It came with the following features:
Use of XML policies with DNS - this was reduced to what is now known as Sender ID
Piggybacking and extension of the existing SPF
Use of RFC 2822 mail header fields as by DomainKeys (All other LMAP drafts used the SMTP envelope.)
Specific questions about patents and licensing
Proceedings
The working group decided to postpone the question of RFC 2821 SMTP identities - i.e. MAIL FROM covered by SPF, or HELO covered by CSV and SPF - in favour of RFC 2822 identities covered by Caller-ID's and later Sender-ID's Purported Responsible Address (PRA). The WG arrived at a point where sender policies could be split into different scopes, like the 2821 MAIL FROM or the 2822 PRA. The MARID syntax also allowed to join different scopes into one policy record, if the sets of permitted IPs are identical, as is often the case.
Less than a week after the publication of a first or MAIL FROM draft, the WG was terminated unilaterally by its leadership. MARID |
https://en.wikipedia.org/wiki/Neonatal%20line | The neonatal line is a particular band of incremental growth lines seen in histologic sections of both enamel and dentin of primary teeth. It belongs to a series of a growth lines in tooth enamel known as the Striae of Retzius denoting the prolonged rest period of enamel formation that occurs at the time of birth. The neonatal line is darker and larger than the rest of the striae of retzius. The neonatal line is the demarcation between the enamel formation before birth and after birth i.e., prenatal and postnatal enamel respectively. It is caused by the different physiologic changes at birth and is used to identify enamel formation before and after birth. The position of the neonatal line differs from tooth to tooth
Formation
The formation of the neonatal line is caused by changes in the direction and degree of tooth mineralization caused by the biological stress from passing into extra uterine life. Specific factors underlying its formation and width still remain unclear.
Forensic Dentistry
In forensic dentistry, the neonatal line can be used to distinguish matters such as if a child died before or after birth and approximately how long a child lived after birth. The neonatal line can be used as a marker for the exact period of survival of an infant through the measurement of the amount of postnatal hard tissue formation and examination of the thickness of the neonatal line. |
https://en.wikipedia.org/wiki/Rollin%20film | A Rollin film, named after Bernard V. Rollin, is a -thick liquid film of helium in the helium II state. It exhibits a "creeping" effect in response to surfaces extending past the film's level (wave propagation). Helium II can escape from any non-closed container via creeping toward and eventually evaporating from capillaries of or greater.
Rollin films are involved in the fountain effect where superfluid helium leaks out of a container in a fountain-like manner. They have high thermal conductivity.
The ability of superfluid liquids to cross obstacles that lie at a higher level is often referred to as the Onnes effect, named after Heike Kamerlingh Onnes. The Onnes effect is enabled by the capillary forces dominating gravity and viscous forces.
Waves propagating across a Rollin film are governed by the same equation as gravity waves in shallow water, but rather than gravity, the restoring force is the van der Waals force. The film suffers a change in chemical potential when the thickness varies. These waves are known as third sound.
Thickness of the film
The thickness of the film can be calculated by the energy balance. Consider a small fluid volume element which is located at a height from the free surface. The potential energy due to the gravitational force acting on the fluid element is , where is the total density and is the gravitational acceleration. The quantum kinetic energy per particle is , where is the thickness of the film and is the mass of the particle. Therefore, the net kinetic energy is given by , where is the fraction of atoms which are Bose–Einstein condensate. Minimizing the total energy with respect to the thickness provides us the value of the thickness:
See also
Second sound |
https://en.wikipedia.org/wiki/Canonical%20analysis | In statistics, canonical analysis (from bar, measuring rod, ruler) belongs to the family of regression methods for data analysis. Regression analysis quantifies a relationship between a predictor variable and a criterion variable by the coefficient of correlation r, coefficient of determination r2, and the standard regression coefficient β. Multiple regression analysis expresses a relationship between a set of predictor variables and a single criterion variable by the multiple correlation R, multiple coefficient of determination R2, and a set of standard partial regression weights β1, β2, etc. Canonical variate analysis captures a relationship between a set of predictor variables and a set of criterion variables by the canonical correlations ρ1, ρ2, ..., and by the sets of canonical weights C and D.
Canonical analysis
Canonical analysis belongs to a group of methods which involve solving the characteristic equation for its latent roots and vectors. It describes formal structures in hyperspace invariant with respect to the rotation of their coordinates. In this type of solution, rotation leaves many optimizing properties preserved, provided it takes place in certain ways and in a subspace of its corresponding hyperspace. This rotation from the maximum intervariate correlation structure into a different, simpler and more meaningful structure increases the interpretability of the canonical weights C and D. In this the canonical analysis differs from Harold Hotelling's (1936) canonical variate analysis (also called the canonical correlation analysis), designed to obtain maximum (canonical) correlations between the predictor and criterion canonical variates. The difference between the canonical variate analysis and canonical analysis is analogous to the difference between the principal components analysis and factor analysis, each with its characteristic set of commonalities, eigenvalues and eigenvectors.
Canonical analysis (simple)
Canonical analysis is a multivari |
https://en.wikipedia.org/wiki/T-money | T-money is a rechargeable series of smart cards and other "smart" devices used for paying transportation fares in and around Seoul and other areas of South Korea. T-money can also be used in lieu of cash or credit cards in some convenience stores and other businesses. The T-money System has been implemented and is being operated by T-money Co., Ltd of which 34.4% owned by Seoul Special City Government, 31.85% owned by LG CNS, and 15.73% owned by Credit Card Union.
History
22 April 2004 : City government announced the name of new transit card called T-money. "T" stands for travel, touch, traffic and technology.
June 2004 : T-money terminals installed at stations. Several bugs had to be ironed out before full operation.
1 July 2004 : System officially inaugurated, with a day of free transit for all.
15 October 2005 : Incheon public transit system started to accept T-money.
6 December 2005 : T-money Internet refilling service started.
13 November 2006 : Gyeonggi-do transit system started to partially accept T-money.
4 August 2008 : Busan urban buses started to accept T-money.
Usage
Similar to its predecessor, the "Seoul Bus Card", T-money can be used to pay for bus, subway and some taxi fares. As of March 2017, T-money is accepted by:
All Seoul, Gyeonggi-do, Incheon, Busan, Daegu, Daejeon, and Gwangju buses
Seoul, Incheon, Busan, Daegu, Daejeon, and Gwangju Metropolitan Subway networks
AREX, U Line, EverLine, Shinbundang Line, Donghae Line (Metro) and Busan–Gimhae Light Rail Transit
All Sejong Special Autonomous City, Chungcheongnam-do and Chungcheongbuk-do buses
All Gangwon-do buses
All Gyeongsangbuk-do and Gyeongsangnam-do buses with dongle
All Jeollabuk-do, Jeollanam-do, and Jeju Special Autonomous Province buses with dongle
Korail ticket office
Toll booth operated by Korea Expressway Corporation
Express bus with E-Pass dongle
Some stores and attractions including Seoul's four palaces (except Gyeonghuigung), Lotte World amusement park, Kyobo |
https://en.wikipedia.org/wiki/Credential | A credential is a piece of any document that details a qualification, competence, or authority issued to an individual by a third party with a relevant or de facto authority or assumed competence to do so.
Examples of credentials include academic diplomas, academic degrees, certifications, security clearances, identification documents, badges, passwords, user names, keys, powers of attorney, and so on. Sometimes publications, such as scientific papers or books, may be viewed as similar to credentials by some people, especially if the publication was peer reviewed or made in a well-known journal or reputable publisher.
Types and documentation of credentials
A person holding a credential is usually given documentation or secret knowledge (e.g., a password or key) as proof of the credential. Sometimes this proof (or a copy of it) is held by a third, trusted party. While in some cases a credential may be as simple as a paper membership card, in other cases, such as diplomas, it involves the presentation of letters directly from the issuer of the credential its faith in the person representing them in a negotiation or meeting.
Counterfeiting of credentials is a constant and serious problem, irrespective of the type of credential. A great deal of effort goes into finding methods to reduce or prevent counterfeiting. In general, the greater the perceived value of the credential, the greater the problem with counterfeiting and the greater the lengths to which the issuer of the credential must go to prevent fraud.
Diplomacy
In diplomacy, credentials, also known as a letter of credence, are documents that ambassadors, diplomatic ministers, plenipotentiary, and chargés d'affaires provide to the government to which they are accredited, for the purpose, chiefly, of communicating to the latter the envoy's diplomatic rank. It also contains a request that full credence be accorded to his official statements. Until his credentials have been presented and found in proper ord |
https://en.wikipedia.org/wiki/Quantum%20weirdness | Quantum weirdness encompasses the aspects of quantum mechanics that challenge and defy human physical intuition based on the Newtonian mechanics of classical physics. These aspects include:
quantum entanglement;
quantum nonlocality, referred to by Einstein as "spooky action at a distance"; see also EPR paradox;
quantum superposition, presented in dramatic form in the thought experiment known as Schrödinger's cat;
the uncertainty principle;
wave–particle duality;
the probabilistic nature of wave function collapse, decried by Einstein, saying, "God does not play dice".
Many attempts have been made to construct an interpretation of quantum mechanics assigning a meaning to the laws of quantum mechanics in terms of an intuitively acceptable model. The so-called Copenhagen interpretation basically holds that the laws are as they are and need no interpretation in such a model.
See also
Bell's theorem
Renninger negative-result experiment
Wheeler's delayed-choice experiment |
https://en.wikipedia.org/wiki/Smart%20bookmark | Smart bookmarks are an extended kind of Internet bookmark used in web browsers. By accepting an argument, they directly give access to functions of web sites, as opposed to filling web forms at the respective web site for accessing these functions. Smart bookmarks can be used for web searches, or access to data on web sites with uniformly structured web addresses (e.g., user profiles in a web forum).
History
Smart bookmarks first were introduced in OmniWeb on the NEXTSTEP platform in 1997/1998, where they were called shortcuts. The feature was subsequently taken up by Opera, Galeon and Internet Explorer for Mac, so they can now be used in many web browsers, most of which are Mozilla based, like Kazehakase and Mozilla Firefox.
In Web, smart bookmarks appear in a dropdown menu when entering text in the address bar. By selecting a smart bookmark the respective web site is accessed using the text as argument. Smart bookmarks can also be added to the toolbar, together with their own textbox. The same applies to Galeon, which also allows the user to collapse and expand the textboxes within the toolbar. Smart bookmarks can also be shared, and there is a collection of them at the web site of the Galeon project.
Usage
There are two ways to employ smart bookmarks: either through the assignment of keywords or without. E.g., Mozilla derivatives and also Konqueror requires the assigning of keywords that can then be typed directly into the address bar followed by the term. Epiphany does not allow assigning keywords. Instead, the term is typed directly into the address bar, then all smart bookmarks appear on the address bar, can be dropped down the list, and selected.
See also
Bookmarklets, making it possible to use javascript with smart bookmarks
iMacros for Firefox, embeds web browser macros in bookmarks or links |
https://en.wikipedia.org/wiki/Double%20electron%20capture | Double electron capture is a decay mode of an atomic nucleus. For a nuclide (A, Z) with a number of nucleons A and atomic number Z, double electron capture is only possible if the mass of the nuclide (A, Z−2) is lower.
In this mode of decay, two of the orbital electrons are captured via the weak interaction by two protons in the nucleus, forming two neutrons (Two neutrinos are emitted in the process). Since the protons are changed to neutrons, the number of neutrons increases by two, while the number of protons Z decreases by two, and the atomic mass number A remains unchanged. As a result, by reducing the atomic number by two, double electron capture transforms the nuclide into a different element.
Example:
{| border="0"
|- style="height:2em;"
| ||+ ||2 ||→ || ||+ ||2
|}
Rarity
In most cases this decay mode is masked by other, more probable modes involving fewer particles, such as single electron capture. When all other modes are “forbidden” (strongly suppressed) double electron capture becomes the main mode of decay. There exist 34 naturally occurring nuclei that are believed to undergo double electron capture, but the process has been confirmed by observation in the decay of only three nuclides: , , and .
One reason is that the probability of double electron capture is stupendously small; the half-lives for this mode lie well above 10 years. A second reason is that the only detectable particles created in this process are X-rays and Auger electrons that are emitted by the excited atomic shell. In the range of their energies (~1–10 keV), the background is usually high. Thus, the experimental detection of double electron capture is more difficult than that for double beta decay.
Double electron capture can be accompanied by the excitation of the daughter nucleus. Its de-excitation, in turn, is accompanied by an emission of photons with energies of hundreds of keV.
Modes with positron emission
If the mass difference between the mother and daughter atoms is |
https://en.wikipedia.org/wiki/Single-event%20upset | A single-event upset (SEU), also known as a single-event error (SEE), is a change of state caused by one single ionizing particle (ions, electrons, photons...) striking a sensitive node in a live micro-electronic device, such as in a microprocessor, semiconductor memory, or power transistors. The state change is a result of the free charge created by ionization in or close to an important node of a logic element (e.g. memory "bit"). The error in device output or operation caused as a result of the strike is called an SEU or a soft error.
The SEU itself is not considered permanently damaging to the transistor's or circuits' functionality unlike the case of single-event latch-up (SEL), single-event gate rupture (SEGR), or single-event burnout (SEB). These are all examples of a general class of radiation effects in electronic devices called single-event effects (SEEs).
History
Single-event upsets were first described during above-ground nuclear testing, from 1954 to 1957, when many anomalies were observed in electronic monitoring equipment. Further problems were observed in space electronics during the 1960s, although it was difficult to separate soft failures from other forms of interference. In 1972, a Hughes satellite experienced an upset where the communication with the satellite was lost for 96 seconds and then recaptured. Scientists Dr. Edward C. Smith, Al Holman, and Dr. Dan Binder explained the anomaly as a single-event upset (SEU) and published the first SEU paper in the IEEE Transactions on Nuclear Science journal in 1975. In 1978, the first evidence of soft errors from alpha particles in packaging materials was described by Timothy C. May and M.H. Woods. In 1979, James Ziegler of IBM, along with W. Lanford of Yale, first described the mechanism whereby a sea-level cosmic ray could cause a single-event upset in electronics. 1979 also saw the world’s first heavy ion "single-event effects" test at a particle accelerator facility, conducted at Lawrence Berke |
https://en.wikipedia.org/wiki/Dirk%20West | Gerald Glynn "Dirk" West (1930 – July 26, 1996) was an editorial cartoonist, journalist, and mayor from Lubbock, Texas, most famous for his caricatures of collegiate mascots. He was born in Littlefield, Texas, but his family moved to Lubbock soon after. He attended Texas Tech University where he drew cartoons for The University Daily student newspaper. He appeared as "Uncle Dirk" on a local children's program for three years while heading up his advertising agency, West Advertising. Beginning in the 1960s, he cartooned for the Lubbock Avalanche-Journal.
Life
West was born October 23, 1928, in Littlefield, Texas, to James Marion and Ethel Raye Bennett West. He died of an heart attack on July 15, 1996, in Lubbock, Texas.
Mascot cartoons
West's most famous works featured caricatures of the sports mascots of various universities, mostly those of the Southwest Conference (and later the Big 12 Conference), but other schools appeared as well, usually because they were playing Texas Tech. His cartoons appeared in program books, on posters, and in magazines.
Two of his characters would eventually be officially adopted by their respective universities: Texas Tech's Raider Red and the University of Nebraska's Herbie Husker.
West drew a semi-weekly one-panel comic in the Avalanche-Journal's sports section where he would lampoon college mascots and coaches alike, as well as the stereotypes of various universities. Thus there was the dim-witted Texas A&M Aggie, the devout but overemotional Baylor Bear, the arrogant University of Texas at Austin Longhorn and of course Raider Red, whose bullet-riddled Stetson showed by the number of holes the number of game losses for Texas Tech so far that season.
West would alter the image of his characters over the course of a sports season. A winning team's mascot would gradually get larger and tougher, the fans of losing teams would find their mascots growing thinner as the weeks went by.
Politics
After serving several years on the local |
https://en.wikipedia.org/wiki/Miller | A miller is a person who operates a mill, a machine to grind a grain (for example corn or wheat) to make flour. Milling is among the oldest of human occupations. "Miller", "Milne" and other variants are common surnames, as are their equivalents in other languages around the world ("Melnyk" in Russian, Belarusian & Ukrainian, "Meunier" in French, "Müller" or "Mueller" in German, "Mulder" and "Molenaar" in Dutch, "Molnár" in Hungarian, "Molinero" in Spanish, "Molinaro" or "Molinari" in Italian, "Mlinar" in South Slavic languages etc.). Milling existed in hunter-gatherer communities, and later millers were important to the development of agriculture.
The materials ground by millers are often foodstuffs and particularly grain. The physical grinding of the food allows for the easier digestion of its nutrients and saves wear on the teeth. Non-food substances needed in a fine, powdered form, such as building materials, may be processed by a miller.
Quern-stone
The most basic tool for a miller was the quern-stone—simply a large, fixed stone as a base and another movable stone operated by hand, similar to a mortar and pestle. As technology and millstones (the bedstone and rynd) improved, more elaborate machines such as watermills and windmills were developed to do the grinding work. These mills harnessed available energy sources including animal, water, wind, and electrical power. Mills are some of the oldest factories in human history, so factories making other items are sometimes known as mills, for example, cotton mills and steel mills. These factory workers are also called millers.
The rynd in pre-reformation Scotland was often carved on millers' gravestones as a symbol of their trade.
Status
In a traditional rural society, a miller is often wealthier than ordinary peasants, which can lead to jealousy. Millers are often accused of associating with thieves, and were targeted in bread riots at times of famine. Conversely, millers might be in a stronger position |
https://en.wikipedia.org/wiki/Saturation%20%28magnetic%29 | Seen in some magnetic materials, saturation is the state reached when an increase in applied external magnetic field H cannot increase the magnetization of the material further, so the total magnetic flux density B more or less levels off. (Though, magnetization continues to increase very slowly with the field due to paramagnetism.) Saturation is a characteristic of ferromagnetic and ferrimagnetic materials, such as iron, nickel, cobalt and their alloys. Different ferromagnetic materials have different saturation levels.
Description
Saturation is most clearly seen in the magnetization curve (also called BH curve or hysteresis curve) of a substance, as a bending to the right of the curve (see graph at right). As the H field increases, the B field approaches a maximum value asymptotically, the saturation level for the substance. Technically, above saturation, the B field continues increasing, but at the paramagnetic rate, which is several orders of magnitude smaller than the ferromagnetic rate seen below saturation.
The relation between the magnetizing field H and the magnetic field B can also be expressed as the magnetic permeability: or the relative permeability , where is the vacuum permeability. The permeability of ferromagnetic materials is not constant, but depends on H. In saturable materials the relative permeability increases with H to a maximum, then as it approaches saturation inverts and decreases toward one.
Different materials have different saturation levels. For example, high permeability iron alloys used in transformers reach magnetic saturation at 1.6–2.2teslas (T), whereas ferrites saturate at 0.2–0.5T. Some amorphous alloys saturate at 1.2–1.3T. Mu-metal saturates at around 0.8T.
Explanation
Ferromagnetic materials (like iron) are composed of microscopic regions called magnetic domains, that act like tiny permanent magnets that can change their direction of magnetization. Before an external magnetic field is applied to the material, |
https://en.wikipedia.org/wiki/Oxford%20Electric%20Bell | The Oxford Electric Bell or Clarendon Dry Pile is an experimental electric bell, in particular a type of bell that uses the electrostatic clock principle that was set up in 1840 and which has run nearly continuously ever since. It was one of the first pieces purchased for a collection of apparatus by clergyman and physicist Robert Walker. It is located in a corridor adjacent to the foyer of the Clarendon Laboratory at the University of Oxford, England, and is still ringing, albeit inaudibly due to being behind two layers of glass.
Design
The experiment consists of two brass bells, each positioned beneath a dry pile (a form of battery), the pair of piles connected in series, giving the bells opposite electric charges. The clapper is a metal sphere approximately in diameter suspended between the piles, which rings the bells alternately due to electrostatic force. When the clapper touches one bell, it is charged by that pile. It is then repelled from that bell due to having the same charge and attracted to the other bell, which has the opposite charge. The clapper then touches the other bell and the process reverses, leading to oscillation. The use of electrostatic forces means that while high voltage is required to create motion, only a tiny amount of charge is carried from one bell to the other. As a result, the batteries drain very slowly, which is why the piles have been able to last since the apparatus was set up in 1840. Its oscillation frequency is 2 hertz.
The exact composition of the dry piles is unknown, but it is known that they have been coated with molten sulfur for insulation and it is thought that they may be Zamboni piles.
At one point this sort of device played an important role in distinguishing between two different theories of electrical action: the theory of contact tension (an obsolete scientific theory based on then-prevailing electrostatic principles) and the theory of chemical action.
The Oxford Electric Bell does not demonstrate perpetual |
https://en.wikipedia.org/wiki/Rewilding | Rewilding may refer to:
Rewilding (conservation biology), the return of habitats to a natural state
Rewilding Europe, a programme to do so in Europe
Pleistocene rewilding, a form of species reintroduction
Rewilding Institute, an organization concerned with the integration of traditional wildlife and wildlands conservation
Rewilding (anarchism), the reversal of human "domestication"
Rewilding (horse), a thoroughbred racehorse
See also
Species reintroduction, the deliberate release of a species into the wild |
https://en.wikipedia.org/wiki/FUJIC | FUJIC was the first electronic digital computer in operation in Japan. It was finished in March 1956, the project having been effectively started in 1949, and was built almost entirely by Dr. Okazaki Bunji. Originally designed to perform calculations for lens design by Fuji, the ultimate goal of FUJIC's construction was to achieve a speed 1,000 times that of human calculation for the same purpose – the actual performance achieved was double that number.
Employing approximately 1,700 vacuum tubes, the computer's word length was 33 bits. It had an ultrasonic mercury delay-line memory of 255 words, with an average access time of 500 microseconds. An addition or subtraction was clocked at 100 microseconds, multiplication at 1,600 microseconds, and division at 2,100 microseconds.
Used extensively for two years at the Fuji factory in Odawara, it was given later to Waseda University before taking up residence in the National Science Museum of Japan in Tokyo.
See also
MUSASINO-1
List of vacuum-tube computers |
https://en.wikipedia.org/wiki/Data%20recovery | In computing, data recovery is a process of retrieving deleted, inaccessible, lost, corrupted, damaged, or formatted data from secondary storage, removable media or files, when the data stored in them cannot be accessed in a usual way. The data is most often salvaged from storage media such as internal or external hard disk drives (HDDs), solid-state drives (SSDs), USB flash drives, magnetic tapes, CDs, DVDs, RAID subsystems, and other electronic devices. Recovery may be required due to physical damage to the storage devices or logical damage to the file system that prevents it from being mounted by the host operating system (OS).
Logical failures occur when the hard drive devices are functional but the user or automated-OS cannot retrieve or access data stored on them. Logical failures can occur due to corruption of the engineering chip, lost partitions, firmware failure, or failures during formatting/re-installation.
Data recovery can be a very simple or technical challenge. This is why there are specific software companies specialized in this field.
About
The most common data recovery scenarios involve an operating system failure, malfunction of a storage device, logical failure of storage devices, accidental damage or deletion, etc. (typically, on a single-drive, single-partition, single-OS system), in which case the ultimate goal is simply to copy all important files from the damaged media to another new drive. This can be accomplished using a Live CD, or DVD by booting directly from a ROM or a USB drive instead of the corrupted drive in question. Many Live CDs or DVDs provide a means to mount the system drive and backup drives or removable media, and to move the files from the system drive to the backup media with a file manager or optical disc authoring software. Such cases can often be mitigated by disk partitioning and consistently storing valuable data files (or copies of them) on a different partition from the replaceable OS system files.
Another sc |
https://en.wikipedia.org/wiki/Native%20resolution | The native resolution of an liquid crystal display (LCD), liquid crystal on silicon (LCoS) or other flat panel display refers to its single fixed resolution. As an LCD consists of a fixed raster, it cannot change resolution to match the signal being displayed as a cathode-ray tube (CRT) monitor can, meaning that optimal display quality can be reached only when the signal input matches the native resolution. An image where the number of pixels is the same as in the image source and where the pixels are perfectly aligned to the pixels in the source is said to be pixel perfect.
While CRT monitors can usually display images at various resolutions, an LCD monitor has to rely on interpolation (scaling of the image), which causes a loss of image quality. An LCD has to scale up a smaller image to fit into the area of the native resolution. This is the same principle as taking a smaller image in an image editing program and enlarging it; the smaller image loses its sharpness when it is expanded. This is especially problematic as most resolutions are in a 4:3 aspect ratio (640×480, 800×600, 1024×768, 1280×960, 1600×1200) but there are odd resolutions that are not, notably 1280×1024. If a user were to map 1024×768 to a 1280×1024 screen there would be distortion as well as some image errors, as there is not a one-to-one mapping with regard to pixels. This results in noticeable quality loss and the image is much less sharp.
In theory, some resolutions could work well, if they are exact multiples of smaller image sizes. For example, a 1600×1200 LCD could display an 800×600 image well, as each of the pixels in the image could be represented by a block of four on the larger display, without interpolation. Since 800×600 is an integer factor of 1600×1200, scaling should not adversely affect the image. But in practice, most monitors apply a smoothing algorithm to all smaller resolutions, so the quality still suffers for these "half" modes.
Most LCD monitors are able to inform the P |
https://en.wikipedia.org/wiki/Heuriger | In eastern Austria, a Heuriger (; Austrian dialect pronunciation: Heiriga) is a tavern where local winemakers serve their new wine under a special licence in alternating months during the growing season. Each state in Austria has slightly varying rules on how many Heuriger of a town can be open at any given time and for how long in total during the year. The Heurige are renowned for their atmosphere of Gemütlichkeit shared among a throng enjoying young wine, simple food, and – in some places – Schrammelmusik. They correspond to the Straußwirtschaften in the German Rheinland, the Frasche in Friuli-Venezia Giulia, and Osmica in Slovenia.
Heuriger is the abbreviation of "heuriger Wein" (this year's wine) in Austrian and Bavarian German. Originally, they were simple open-air taverns on the premises of winemakers, where people would bring along food and drink the new wine. Nowadays, the taverns are often situated at a distance from the wineyards and offer both food and drinks. Heurige where apple or pear cider is served are called Mostheurige. In the well-known wine-growing areas of the city of Vienna (Grinzing, Sievering, Neustift, Liesing) many eating establishments have a rustic interior design similar to Heurige, yet they have a normal licence and sell wine they buy from outside sources.
History
On 17 August 1784 Austrian Emperor Joseph II issued a decree that permitted all residents to open establishments to sell and serve self-produced wine and juices. At first no food could be sold in order to prevent competition with restaurants, but over time these restrictions lessened.
Ausg'steckt would be a sign that the wine farmer was serving out the wine at a Heuriger.
Over the years well-known areas for Heurigen developed, including Dürnstein, Gainfarn, Gamlitz, Guntramsdorf, Gumpoldskirchen, Grinzing, Königstetten, Langenlois, Mauer, Neustift am Walde, Perchtoldsdorf, Pfaffstätten, Rust, Sievering, Traiskirchen, Tribuswinkel and the Wachau region.
Many of the town |
https://en.wikipedia.org/wiki/BartPE | BartPE (Bart's Preinstalled Environment) is a discontinued tool that customizes Windows XP or Windows Server 2003 into a lightweight environment, similar to Windows Preinstallation Environment, which could be run from a Live CD or Live USB drive. A BartPE system image is created using PE Builder, a freeware program created by Bart Lagerweij.
It requires a legal copy of Windows XP or Windows Server 2003. Additional applications can be included in the image using plugins.
As it often resides on a Live CD or USB drive, BartPE allows a user to boot Windows, even if a hardware or software fault has disabled the installed operating system(s) on the internal hard drive – for instance, to recover files. It can also be used to scan for and remove rootkits, computer viruses and spyware (that have infected boot files), or to reset a lost administrator password.
Overview
While a bootable floppy disk can be used to help recover a failing hard disk, one major limitation on using a floppy disk that booted a standalone copy of MS-DOS was that "DOS can't handle NTFS hard-drive partitions."
BartPE is a reasonable first choice for Windows users: it's free, and it's #2 in a list of alternatives; #1 is Linux-oriented. While it can be used for running demos, it can also be used "to bring a dead PC back to life."
PE Builder
PE Builder (also known as Bart PE Builder) is the software used to create the BartPE system images.
Description
As with Windows Preinstallation Environment, BartPE operates by loading system registry files into RAM, and not writing any registry changes back to boot media. Thus, neither operating system requires an operational hard drive or network access. This also allows them to be run from non-writable media such as a CD-ROM.
Since each instance of BartPE is a new installation, the BartPE "boot" disk needs original Windows Setup files in order to operate. The Bart PE Builder application interprets and condenses files from a Windows setup CD to create the Bart |
https://en.wikipedia.org/wiki/Dynamical%20billiards | A dynamical billiard is a dynamical system in which a particle alternates between free motion (typically as a straight line) and specular reflections from a boundary. When the particle hits the boundary it reflects from it without loss of speed (i.e. elastic collisions). Billiards are Hamiltonian idealizations of the game of billiards, but where the region contained by the boundary can have shapes other than rectangular and even be multidimensional. Dynamical billiards may also be studied on non-Euclidean geometries; indeed, the first studies of billiards established their ergodic motion on surfaces of constant negative curvature. The study of billiards which are kept out of a region, rather than being kept in a region, is known as outer billiard theory.
The motion of the particle in the billiard is a straight line, with constant energy, between reflections with the boundary (a geodesic if the Riemannian metric of the billiard table is not flat). All reflections are specular: the angle of incidence just before the collision is equal to the angle of reflection just after the collision. The sequence of reflections is described by the billiard map that completely characterizes the motion of the particle.
Billiards capture all the complexity of Hamiltonian systems, from integrability to chaotic motion, without the difficulties of integrating the equations of motion to determine its Poincaré map. Birkhoff showed that a billiard system with an elliptic table is integrable.
Equations of motion
The Hamiltonian for a particle of mass m moving freely without friction on a surface is:
where is a potential designed to be zero inside the region in which the particle can move, and infinity otherwise:
This form of the potential guarantees a specular reflection on the boundary. The kinetic term guarantees that the particle moves in a straight line, without any change in energy. If the particle is to move on a non-Euclidean manifold, then the Hamiltonian is replaced by |
https://en.wikipedia.org/wiki/Cross%20Cave | Cross Cave (, ), also named Cold Cave under Cross Mountain (), is a cave in Slovenia's Lož Valley, in the area between the Lož Karst Field, Cerknica Karst Field, and Bloke Plateau. The cave is named after nearby Holy Cross Church in Podlož. The cave is particularly noted among Karst caves for its chain of over 45 subterranean lakes of emerald green water. Extremely slow-growing calcareous formations (up to 0.1 mm per year) and their fragility are the main obstacle to large-scale tourism in the cave and limit daily tourist visits to the flooded part of the cave to four people. As a result, the Cross Cave is among the best-preserved caves, opened to the public in Slovenia. The cave was prepared for visits in the 1950s by the Lož Valley Tourist Association. It was later managed by the Ljubljana Cave Research Society. Since the 1990s, it has been cared for by the Friends of Cross Cave Association ().
With 45 species of organisms, some not discovered until 2000, Cross Cave is the fourth-largest cave ecosystem in the world in terms of biodiversity. The cave was first documented in 1832, but the part of the cave that includes lakes and stream passages was first explored by Slovene cavers in 1926.
Course
At Calvary (, the best-known symbol of Cross Cave), the cave splits into two branches: the Muds to the north and the Variegated Passage to the northeast. The passage through the Muds is more difficult, and so most visitors choose to continue through the Variegated Passage, which requires the use of small boats. Cross Cave continues into New Cross Cave (). In the direction from the entrance to the cave, the Variegated Passage is the left gallery of Cross Cave at the confluence with the Muds at Cavalry. The access requires the use of boats. Part of the way along the Variegated Passage is a side gallery named the Matjaž Passage (), and it contains several large columns. Continuing along the Variegated Passage, visitors enter the Crystal Mountain (), the largest room in the c |
https://en.wikipedia.org/wiki/Eigenvalues%20and%20eigenvectors | In linear algebra, an eigenvector () or characteristic vector of a linear transformation is a nonzero vector that changes at most by a constant factor when that linear transformation is applied to it. The corresponding eigenvalue, often represented by , is the multiplying factor.
Geometrically, a transformation matrix rotates, stretches, or shears the vectors it acts upon. The eigenvectors for a linear transformation matrix are the set of vectors that are only stretched, with no rotation or shear. The eigenvalue is the factor by which an eigenvector is stretched. If the eigenvalue is negative, the direction is reversed.
Definition
If is a linear transformation from a vector space over a field into itself and is a nonzero vector in , then is an eigenvector of if is a scalar multiple of . This can be written as
where is a scalar in , known as the eigenvalue, characteristic value, or characteristic root associated with .
There is a direct correspondence between n-by-n square matrices and linear transformations from an n-dimensional vector space into itself, given any basis of the vector space. Hence, in a finite-dimensional vector space, it is equivalent to define eigenvalues and eigenvectors using either the language of matrices, or the language of linear transformations.
If is finite-dimensional, the above equation is equivalent to
where is the matrix representation of and is the coordinate vector of .
Overview
Eigenvalues and eigenvectors feature prominently in the analysis of linear transformations. The prefix eigen- is adopted from the German word eigen (cognate with the English word own) for 'proper', 'characteristic', 'own'. Originally used to study principal axes of the rotational motion of rigid bodies, eigenvalues and eigenvectors have a wide range of applications, for example in stability analysis, vibration analysis, atomic orbitals, facial recognition, and matrix diagonalization.
In essence, an eigenvector v of a linear transformatio |
https://en.wikipedia.org/wiki/Yan%20tan%20tethera | Yan Tan Tethera or yan-tan-tethera is a sheep-counting system traditionally used by shepherds in Northern England and some other parts of Britain. The words are numbers taken from Brythonic Celtic languages such as Cumbric which had died out in most of Northern England by the sixth century, but they were commonly used for sheep counting and counting stitches in knitting until the Industrial Revolution, especially in the fells of the Lake District. Though most of these number systems fell out of use by the turn of the 20th century, some are still in use.
Origin and development
Sheep-counting systems ultimately derive from Brythonic Celtic languages, such as Cumbric; Tim Gay writes: “[Sheep-counting systems from all over the British Isles] all compared very closely to 18th-century Cornish and modern Welsh". It is impossible, given the corrupted form in which they have survived, to be sure of their exact origin. The counting systems have changed considerably over time. A particularly common tendency is for certain pairs of adjacent numbers to come to resemble each other by rhyme (notably the words for 1 and 2, 3 and 4, 6 and 7, or 8 and 9). Still, multiples of five tend to be fairly conservative; compare bumfit with Welsh pymtheg, in contrast with standard English fifteen.
Use in sheep counting
Like most Celtic numbering systems, they tend to be vigesimal (based on the number twenty), but they usually lack words to describe quantities larger than twenty; this is not a limitation of either modernised decimal Celtic counting systems or the older ones. To count a large number of sheep, a shepherd would repeatedly count to twenty, placing a mark on the ground, or move a hand to another mark on a shepherd's crook, or drop a pebble into a pocket to represent each score (e.g. 5 score sheep = 100 sheep).
Importance of keeping count
In order to keep accurate records (e.g. of birth and death) and to be alert to instances of straying, shepherds must perform frequent head |
https://en.wikipedia.org/wiki/Rasch%20model | The Rasch model, named after Georg Rasch, is a psychometric model for analyzing categorical data, such as answers to questions on a reading assessment or questionnaire responses, as a function of the trade-off between the respondent's abilities, attitudes, or personality traits, and the item difficulty. For example, they may be used to estimate a student's reading ability or the extremity of a person's attitude to capital punishment from responses on a questionnaire. In addition to psychometrics and educational research, the Rasch model and its extensions are used in other areas, including the health profession, agriculture, and market research.
The mathematical theory underlying Rasch models is a special case of item response theory. However, there are important differences in the interpretation of the model parameters and its philosophical implications that separate proponents of the Rasch model from the item response modeling tradition. A central aspect of this divide relates to the role of specific objectivity, a defining property of the Rasch model according to Georg Rasch, as a requirement for successful measurement.
Overview
The Rasch model for measurement
In the Rasch model, the probability of a specified response (e.g. right/wrong answer) is modeled as a function of person and item parameters. Specifically, in the original Rasch model, the probability of a correct response is modeled as a logistic function of the difference between the person and item parameter. The mathematical form of the model is provided later in this article. In most contexts, the parameters of the model characterize the proficiency of the respondents and the difficulty of the items as locations on a continuous latent variable. For example, in educational tests, item parameters represent the difficulty of items while person parameters represent the ability or attainment level of people who are assessed. The higher a person's ability relative to the difficulty of an item, the higher |
https://en.wikipedia.org/wiki/Rose%20oil | Rose oil (rose otto, attar of rose, attar of roses, or rose essence) is the essential oil extracted from the petals of various types of rose. Rose ottos are extracted through steam distillation, while rose absolutes are obtained through solvent extraction, the absolute being used more commonly in perfumery. The production technique originated in Greater Iran. Even with their high price and the advent of organic synthesis, rose oils are still perhaps the most widely used essential oil in perfumery.
Damascena and Centifolia
Two major species of rose are cultivated for the production of rose oil:
Rosa damascena production today is dominated by 3 producers account for over 70% of the Rose oil market share
Bulgaria, Bulgarian Rose
Turkey, Turkish Rose
Saudi Arabia, Taif Rose
It is also grown on a smaller scale in Afghanistan, Armenia, Azebaijan, Bosnia, Croatia, Cyprus, Ethiopia, Georgia, Greece, Jordan, Lebanon, India, Iran, Iraq, Israel, Moldova, North Macedonia, Oman, Serbia, Syria, Tajikistan, Turkmenistan, Pakistan, Romania, Russia, Ukraine, United Arab Emirates and Yemen.
Rosa centifolia, the cabbage rose, which is more commonly grown in Morocco, Egypt and France.
Rosa Damascena composition
Composition of Rose oil & headspace vary, but the Rose international standard survey of 2003-2020 lists 3 components as the major components with a specific range specified in ISO 9842:2003.
Major Rose components
Citronellol 20%-34%
Geraniol 15%-22%
Nonadecane 8%-15%
Minor Rose components
heneicosane, eicosane, docosane, tricosane, tetracosane, pentacosane, hexacosane, heptacosane, nonacosane, dodecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, nerol, linalool, phenyl ethyl alcohol, farnesol, α-pinene, β-pinene, α-terpinene, limonene, p-cymene, camphene, β-caryophyllene, neral,
geranyl acetate, neryl acetate, eugenol, methyl eugenol, benzaldehyde, benzyl alcohol, octane and tetradecanol.
Key Rose components
β-damascenone (0.01% - 1.85%)
β- |
https://en.wikipedia.org/wiki/Padovan%20sequence | In number theory, the Padovan sequence is the sequence of integers P(n) defined by the initial values
and the recurrence relation
The first few values of P(n) are
1, 1, 1, 2, 2, 3, 4, 5, 7, 9, 12, 16, 21, 28, 37, 49, 65, 86, 114, 151, 200, 265, ...
A Padovan prime is a Padovan number that is prime. The first Padovan primes are:
2, 3, 5, 7, 37, 151, 3329, 23833, 13091204281, 3093215881333057, 1363005552434666078217421284621279933627102780881053358473, 1558877695141608507751098941899265975115403618621811951868598809164180630185566719, ... .
The Padovan sequence is named after Richard Padovan who attributed its discovery to Dutch architect Hans van der Laan in his 1994 essay Dom. Hans van der Laan : Modern Primitive. The sequence was described by Ian Stewart in his Scientific American column Mathematical Recreations in June 1996. He also writes about it in one of his books, "Math Hysteria: Fun Games With Mathematics".
The above definition is the one given by Ian Stewart and by MathWorld. Other sources may start the sequence at a different place, in which case some of the identities in this article must be adjusted with appropriate offsets.
Recurrence relations
In the spiral, each triangle shares a side with two others giving a visual proof that
the Padovan sequence also satisfies the recurrence relation
Starting from this, the defining recurrence and other recurrences as they are discovered,
one can create an infinite number of further recurrences by repeatedly replacing by
The Perrin sequence satisfies the same recurrence relations as the Padovan sequence, although it has different initial values.
The Perrin sequence can be obtained from the Padovan sequence by the
following formula:
Extension to negative parameters
As with any sequence defined by a recurrence relation, Padovan numbers P(m) for m<0 can be defined by rewriting the recurrence relation as
Starting with m = −1 and working backwards, we extend P(m) to negative indices:
{| class="wikitabl |
https://en.wikipedia.org/wiki/Protein%E2%80%93protein%20interaction | Protein–protein interactions (PPIs) are physical contacts of high specificity established between two or more protein molecules as a result of biochemical events steered by interactions that include electrostatic forces, hydrogen bonding and the hydrophobic effect. Many are physical contacts with molecular associations between chains that occur in a cell or in a living organism in a specific biomolecular context.
Proteins rarely act alone as their functions tend to be regulated. Many molecular processes within a cell are carried out by molecular machines that are built from numerous protein components organized by their PPIs. These physiological interactions make up the so-called interactomics of the organism, while aberrant PPIs are the basis of multiple aggregation-related diseases, such as Creutzfeldt–Jakob and Alzheimer's diseases.
PPIs have been studied with many methods and from different perspectives: biochemistry, quantum chemistry, molecular dynamics, signal transduction, among others. All this information enables the creation of large protein interaction networks – similar to metabolic or genetic/epigenetic networks – that empower the current knowledge on biochemical cascades and molecular etiology of disease, as well as the discovery of putative protein targets of therapeutic interest.
Examples
Electron transfer proteins
In many metabolic reactions, a protein that acts as an electron carrier binds to an enzyme that acts as its reductase. After it receives an electron, it dissociates and then binds to the next enzyme that acts as its oxidase (i.e. an acceptor of the electron). These interactions between proteins are dependent on highly specific binding between proteins to ensure efficient electron transfer. Examples: mitochondrial oxidative phosphorylation chain system components cytochrome c-reductase / cytochrome c / cytochrome c oxidase; microsomal and mitochondrial P450 systems.
In the case of the mitochondrial P450 systems, the specific residues |
https://en.wikipedia.org/wiki/Proctitis | Proctitis is an inflammation of the anus and the lining of the rectum, affecting only the last 6 inches of the rectum.
Signs and symptoms
A common symptom is a continual urge to have a bowel movement—the rectum could feel full or have constipation. Another is tenderness and mild irritation in the rectum and anal region. A serious symptom is pus and blood in the discharge, accompanied by cramps and pain during the bowel movement. If there is severe bleeding, anemia can result, showing symptoms such as pale skin, irritability, weakness, dizziness, brittle nails, and shortness of breath.
Symptoms are ineffectual straining to empty the bowels, diarrhea, rectal bleeding and possible discharge, a feeling of not having adequately emptied the bowels, involuntary spasms and cramping during bowel movements, left-sided abdominal pain, passage of mucus through the rectum, and anorectal pain.
Sexually transmitted proctitis
Gonorrhea (Gonococcal proctitis)
This is the most common cause. Strongly associated with anal intercourse. Symptoms include soreness, itching, bloody or pus-like discharge, or diarrhea.
Chlamydia (chlamydia proctitis)
Accounts for twenty percent of cases. People may show no symptoms, mild symptoms, or severe symptoms. Mild symptoms include rectal pain with bowel movements, rectal discharge, and cramping. With severe cases, people may have discharge containing blood or pus, severe rectal pain, and diarrhea. Some people have rectal strictures, a narrowing of the rectal passageway. The narrowing of the passageway may cause constipation, straining, and thin stools.
Herpes Simplex Virus 1 and 2 (herpes proctitis)
Symptoms may include multiple vesicles that rupture to form ulcers, tenesmus, rectal pain, discharge, hematochezia. The disease may run its natural course of exacerbations and remissions but is usually more prolonged and severe in patients with immunodeficiency disorders. Presentations may resemble dermatitis or decubitus ulcers in debilitated, bedrid |
https://en.wikipedia.org/wiki/Genetic%20predisposition | A genetic predisposition is a genetic characteristic which influences the possible phenotypic development of an individual organism within a species or population under the influence of environmental conditions. In medicine, genetic susceptibility to a disease refers to a genetic predisposition to a health problem, which may eventually be triggered by particular environmental or lifestyle factors, such as tobacco smoking or diet. Genetic testing is able to identify individuals who are genetically predisposed to certain diseases.
Behavior
Predisposition is the capacity humans are born with to learn things such as language and concept of self. Negative environmental influences may block the predisposition (ability) one has to do some things. Behaviors displayed by animals can be influenced by genetic predispositions. Genetic predisposition towards certain human behaviors is scientifically investigated by attempts to identify patterns of human behavior that seem to be invariant over long periods of time and in very different cultures.
For example, philosopher Daniel Dennett has proposed that humans are genetically predisposed to have a theory of mind because there has been evolutionary selection for the human ability to adopt the intentional stance. The intentional stance is a useful behavioral strategy by which humans assume that others have minds like their own. This assumption allows one to predict the behavior of others based on personal knowledge.
In 1951, Hans Eysenck and Donald Prell published an experiment in which identical (monozygotic) and fraternal (dizygotic) twins, ages 11 and 12, were tested for neuroticism. It is described in detail in an article published in the Journal of Mental Science. in which Eysenck and Prell concluded that, "The factor of neuroticism is not a statistical artifact, but constitutes a biological unit which is inherited as a whole....neurotic Genetic predisposition is to a large extent hereditarily determined."
E. O. Wilson' |
https://en.wikipedia.org/wiki/Rapid%20thermal%20processing | Rapid thermal processing (RTP) is a semiconductor manufacturing process which heats silicon wafers to temperatures exceeding 1,000°C for not more than a few seconds. During cooling wafer temperatures must be brought down slowly to prevent dislocations and wafer breakage due to thermal shock. Such rapid heating rates are often attained by high intensity lamps or lasers. These processes are used for a wide variety of applications in semiconductor manufacturing including dopant activation, thermal oxidation, metal reflow and chemical vapor deposition.
Temperature control
One of the key challenges in rapid thermal processing is accurate measurement and control of the wafer temperature. Monitoring the ambient with a thermocouple has only recently become feasible, in that the high temperature ramp rates prevent the wafer from coming to thermal equilibrium with the process chamber. One temperature control strategy involves in situ pyrometry to effect real time control. Used for melting iron for welding purposes.
Rapid thermal anneal
Rapid thermal anneal (RTA) in rapid thermal processing is a process used in semiconductor device fabrication which involves heating a single wafer at a time in order to affect its electrical properties. Unique heat treatments are designed for different effects. Wafers can be heated in order to activate dopants, change film-to-film or film-to-wafer substrate interfaces, densify deposited films, change states of grown films, repair damage from ion implantation, move dopants or drive dopants from one film into another or from a film into the wafer substrate.
Rapid thermal anneals are performed by equipment that heats a single wafer at a time using either lamp based heating, a hot chuck, or a hot plate that a wafer is brought near. Unlike furnace anneals they are of short duration, processing each wafer in several minutes.
To achieve short annealing times and quick throughput, sacrifices are made in temperature and process uniformity, temp |
https://en.wikipedia.org/wiki/Hitachi%20Flora%20Prius | The Hitachi Flora Prius was a range of personal computers marketed in Japan by Hitachi, Ltd. during the late 1990s.
The Flora Prius was preinstalled with both Microsoft Windows 98 as well as BeOS. It did not, however, have a dual-boot option as Microsoft reminded Hitachi of the terms of the Windows OEM license. In effect, two thirds of the hard drive was hidden from the end-user, and a series of complicated manipulations was necessary to activate the BeOS partition.
Models
FLORA Prius 330J came in three models:
330N40JB: Base version with no LCD Screen
3304ST40JB: Included a 14.1-inch super TFT color LCD Display
3304ST40JBT: Included a 14.1-inch super TFT color LCD Display and WinTV Video capture board
Base specifications
CPU: Pentium II processor (400 MHz)
RAM: 64 MB SDRAM
Hard Drive: 6.4 GB (2 GB for Windows 98 and 4.6 GB for BeOS)
CD-ROM Drive: 24X speed max.
100BASE-TX/10BASE-10 |
https://en.wikipedia.org/wiki/Textile%20manufacturing | Textile manufacturing (or textile engineering) is a major industry. It is largely based on the conversion of fibre into yarn, then yarn into fabric. These are then dyed or printed, fabricated into cloth which is then converted into useful goods such as clothing, household items, upholstery and various industrial products.
Different types of fibres are used to produce yarn. Cotton remains the most widely used and common natural fiber making up 90% of all-natural fibers used in the textile industry. People often use cotton clothing and accessories because of comfort, not limited to different weathers. There are many variable processes available at the spinning and fabric-forming stages coupled with the complexities of the finishing and colouration processes to the production of a wide range of products.
History
Textile manufacturing in the modern era is an evolved form of the art and craft industries. Until the 18th and 19th centuries, the textile industry was a household work. It became mechanised in the 18th and 19th centuries, and has continued to develop through science and technology in the twentieth and twenty-first centuries.
Processing of cotton
Cotton is the world's most important natural fibre. In the year 2007, the global yield was 25 million tons from 35 million hectares cultivated in more than 50 countries.
There are six stages to the manufacturing of cotton textiles:
Cultivating and Harvesting
Preparatory Processes
Spinning
Weaving or Knitting
Finishing
Marketing
Cultivating and harvesting
Cotton is grown in locations with long, hot, dry summers with plenty of sunshine and low humidity. Indian cotton, Gossypium arboreum, is finer but the staple is only suitable for hand processing. American cotton, Gossypium hirsutum, produces the longer staple needed for mechanised textile production. The planting season is from September to mid-November, and the crop is harvested between March and June. The cotton bolls are harvested by stripper harvesters |
https://en.wikipedia.org/wiki/The%20Jim%20Rome%20Show | The Jim Rome Show is a sports radio talk show hosted by Jim Rome. It airs live for three hours each weekday from 9 a.m. to noon Pacific Time. The show is produced in Los Angeles, syndicated by CBS Sports Radio, and can be heard on affiliate radio stations in the U.S. and Canada. In January 2018, the show began simulcasting on television on CBS Sports Network.
History
The Jim Rome Show began on XTRA Sports 690 in San Diego. In 1996, Premiere Radio Networks picked up the program for national syndication. Sometime after, the show was shortened by one hour and the broadcast location was shifted from XTRA Sports 690 to the Premiere Radio Networks studio complex in Sherman Oaks, California. As part of the broadcast deal bringing Rome's TV show to CBS Sports Network, The Jim Rome Show became a charter program of CBS Sports Radio upon its full launch on January 2, 2013.
Show personnel ("The XR4Ti")
Tom Di Benedetto, executive producer, call screener since 2021
Alvin Delloro, engineer since 2005
James "Flight Deck" Kelley, digital program director since approximately 2010
Jack Savage, producer since February 2023
Former personnel
Brian "Whitey" Albers, engineer from 1996 to 2005
Keith Arnold, associate producer from 2016 to 2019
Kyle Brandt, producer and writer from 2007 until July 22, 2016
Robert Dozmati, associate producer from 2018 to 2019
Adam Hawk, executive producer and call screener from 2016 to July 23, 2021
Austin Huff, content screener from 2015 to 2018
Gerrit Ritt, producer from 2019 to January 30, 2023
Travis Rodgers, producer from 1996 to 2009
Jason Stewart, talent coordinator and call screener from 1999 to March 8, 2013
Dave Whelan, producer from 2007 to September 2, 2022
Show format and content
The three-hour program is a mixture of interviews, calls, emails, Tweets and Rome's own thoughts and analysis. On the radio, the opening and closing theme is "Lust for Life" by Iggy Pop, and the show also uses "Welcome to the Jungle" by Guns N' Roses, while CBS Spo |
https://en.wikipedia.org/wiki/List%20of%20plant%20communities%20in%20the%20British%20National%20Vegetation%20Classification | The following is the list of the 286 plant communities which comprise the British National Vegetation Classification (NVC). These are grouped by major habitat category, as used in the five volumes of British Plant Communities, the standard work describing the NVC.
Woodland and scrub communities
The following 25 communities are described in Volume 1 of British Plant Communities. For an article summarising these communities see Woodland and scrub communities in the British National Vegetation Classification system.
W1 Salix cinerea - Galium palustre woodland
W2 Salix cinerea - Betula pubescens - Phragmites australis woodland
W3 Salix pentandra - Carex rostrata woodland
W4 Betula pubescens - Molinia caerulea woodland
W5 Alnus glutinosa - Carex paniculata woodland
W6 Alnus glutinosa - Urtica dioica woodland
W7 Alnus glutinosa - Fraxinus excelsior - Lysimachia nemorum woodland
W8 Fraxinus excelsior - Acer campestre - Mercurialis perennis woodland
W9 Fraxinus excelsior - Sorbus aucuparia - Mercurialis perennis woodland
W10 Quercus robur - Pteridium aquilinum - Rubus fruticosus woodland
W11 Quercus petraea - Betula pubescens - Oxalis acetosella woodland
W12 Fagus sylvatica - Mercurialis perennis woodland
W13 Taxus baccata woodland
W14 Fagus sylvatica - Rubus fruticosus woodland
W15 Fagus sylvatica - Deschampsia flexuosa woodland
W16 Quercus spp. - Betula spp. - Deschampsia flexuosa woodland
W17 Quercus petraea - Betula pubescens - Dicranum majus woodland
W18 Pinus sylvestris - Hylocomium splendens woodland
W19 Juniperus communis ssp. communis - Oxalis acetosella woodland
W20 Salix lapponum - Luzula sylvatica scrub
W21 Crataegus monogyna - Hedera helix scrub
W22 Prunus spinosa - Rubus fruticosus scrub
W23 Ulex europaeus - Rubus fruticosus scrub
W24 Rubus fruticosus - Holcus lanatus underscrub
W25 Pteridium aquilinum - Rubus fruticosus underscrub
Mires
The following 38 communities are described in Volume 2 of British Plant Communities. For an |
https://en.wikipedia.org/wiki/Negative%20air%20ionization%20therapy | Negative air ionization therapy (NAIs) uses air ionisers as a non-pharmaceutical treatment for respiratory disease, allergy, or stress-related health conditions. The mainstream scientific community considers many applications of NAIs to be pseudoscience. Many negative ion products release ozone, a chemical known to cause lung damage.
Research
For Seasonal Affective Disorder (SAD), a randomized controlled trial (RCT) comparing high (4.5x1014 ions/second) and low (1.7x1011 ions/second) flow rate negative air ionization with bright light therapy found that the post-treatment improvement percentage was 57.1% for bright light, 47.9% for high-density ions and 22.7% for low-density ions. An older RCT conducted by the same authors also found air ionization effective for SAD. A 2007 review considers this therapy "under investigation" and suggests that it may be a helpful treatment for SAD.
An RCT comparing the short-term effects of bright light, an auditory stimulus, and high and low-density negative ions on mood and alertness in mildly depressed and non-depressed adults found that the three first (active) stimuli, but not the low-density placebo, reduced depression on the Beck Depression Inventory scale. The auditory stimulus, bright light, and high-density ions all produced rapid mood changes - with small to medium effect sizes - in depressed and non-depressed subjects.
Researchers have continued to cite a dearth of evidence about the effects of negative air ionization. "The presence of NAIs is credited for increasing psychological health, productivity, and overall well-being but without consistent or reliable evidence in therapeutic effects and with controversy in anti-microorganisms," researchers wrote in a 2018 article published in the International Journal of Molecular Sciences.
See also
Topics characterized as pseudoscience
Ionized bracelet
Earthing therapy
Water ionizer |
https://en.wikipedia.org/wiki/Sean%20B.%20Carroll | Sean B. Carroll (born September 17, 1960) is an American evolutionary developmental biologist, author, educator and executive producer. He is a distinguished university professor at the University of Maryland and professor emeritus of molecular biology and genetics at the University of Wisconsin–Madison. His studies focus on the evolution of cis-regulatory elements in the regulation of gene expression in the context of biological development, using Drosophila as a model system. He is a member of the National Academy of Sciences, of the American Philosophical Society (2007), of the American Academy of Arts and Sciences and the American Association for Advancement of Science. He is a Howard Hughes Medical Institute investigator.
Carroll has received the Shaw Scientist Award from the Greater Milwaukee Foundation, the Stephen Jay Gould Prize from the Society for the Study of Evolution, the Benjamin Franklin Medal in Life Science, and the Lewis Thomas Prize at Rockefeller University.
Biography
Sean B. Carroll was born in Toledo, Ohio. He is of Irish ancestry. He has stated that, as a child, he would flip over rocks looking for snakes while attending Maumee Valley Country Day School, and at age 11 or 12, he started keeping snakes. This activity led him to notice the patterns on the snakes and wonder how those form. He got his B.A. in Biology at Washington University in St. Louis, his Ph.D. in immunology from Tufts University and did post-doctoral work at the University of Colorado Boulder.
Career
Carroll is at the forefront of evolutionary developmental biology (also called "evo-devo"), studying how gene changes control the evolution of body parts and patterns. He is the Allan Wilson Professor of Molecular Biology and Genetics at the University of Wisconsin–Madison and an investigator for the Howard Hughes Medical Institute. In 1987, Carroll set up a laboratory at the University of Wisconsin-Madison "focused on understanding how genes get used in different ways to ge |
https://en.wikipedia.org/wiki/Dini%20derivative | In mathematics and, specifically, real analysis, the Dini derivatives (or Dini derivates) are a class of generalizations of the derivative. They were introduced by Ulisse Dini, who studied continuous but nondifferentiable functions.
The upper Dini derivative, which is also called an upper right-hand derivative, of a continuous function
is denoted by and defined by
where is the supremum limit and the limit is a one-sided limit. The lower Dini derivative, , is defined by
where is the infimum limit.
If is defined on a vector space, then the upper Dini derivative at in the direction is defined by
If is locally Lipschitz, then is finite. If is differentiable at , then the Dini derivative at is the usual derivative at .
Remarks
The functions are defined in terms of the infimum and supremum in order to make the Dini derivatives as "bullet proof" as possible, so that the Dini derivatives are well-defined for almost all functions, even for functions that are not conventionally differentiable. The upshot of Dini's analysis is that a function is differentiable at the point on the real line (), only if all the Dini derivatives exist, and have the same value.
Sometimes the notation is used instead of and is used instead of .
Also,
and
.
So when using the notation of the Dini derivatives, the plus or minus sign indicates the left- or right-hand limit, and the placement of the sign indicates the infimum or supremum limit.
There are two further Dini derivatives, defined to be
and
.
which are the same as the first pair, but with the supremum and the infimum reversed. For only moderately ill-behaved functions, the two extra Dini derivatives aren't needed. For particularly badly behaved functions, if all four Dini derivatives have the same value () then the function is differentiable in the usual sense at the point .
On the extended reals, each of the Dini derivatives always exist; however, they may take on the values or at times (i.e., the Din |
https://en.wikipedia.org/wiki/Sieve%20%28category%20theory%29 | In category theory, a branch of mathematics, a sieve is a way of choosing arrows with a common codomain. It is a categorical analogue of a collection of open subsets of a fixed open set in topology. In a Grothendieck topology, certain sieves become categorical analogues of open covers in topology. Sieves were introduced by in order to reformulate the notion of a Grothendieck topology.
Definition
Let C be a category, and let c be an object of C. A sieve on c is a subfunctor of Hom(−, c), i.e., for all objects c′ of C, S(c′) ⊆ Hom(c′, c), and for all arrows f:c″→c′, S(f) is the restriction of Hom(f, c), the pullback by f (in the sense of precomposition, not of fiber products), to S(c′); see the next section, below.
Put another way, a sieve is a collection S of arrows with a common codomain that satisfies the condition, "If g:c′→c is an arrow in S, and if f:c″→c′ is any other arrow in C, then gf is in S." Consequently, sieves are similar to right ideals in ring theory or filters in order theory.
Pullback of sieves
The most common operation on a sieve is pullback. Pulling back a sieve S on c by an arrow f:c′→c gives a new sieve f*S on c′. This new sieve consists of all the arrows in S that factor through c′.
There are several equivalent ways of defining f*S. The simplest is:
For any object d of C, f*S(d) = { g:d→c′ | fg ∈ S(d)}
A more abstract formulation is:
f*S is the image of the fibered product S×Hom(−, c)Hom(−, c′) under the natural projection S×Hom(−, c)Hom(−, c′)→Hom(−, c′).
Here the map Hom(−, c′)→Hom(−, c) is Hom(f, c′), the pullback by f.
The latter formulation suggests that we can also take the image of S×Hom(−, c)Hom(−, c′) under the natural map to Hom(−, c). This will be the image of f*S under composition with f. For each object d of C, this sieve will consist of all arrows fg, where g:d→c′ is an arrow of f*S(d). In other words, it consists of all arrows in S that can be factored through f.
If we denote by ∅c the empty sieve on c, that |
https://en.wikipedia.org/wiki/Stable%20storage | Stable storage is a classification of computer data storage technology that guarantees atomicity for any given write operation and allows software to be written that is robust against some hardware and power failures. To be considered atomic, upon reading back a just written-to portion of the disk, the storage subsystem must return either the write data or the data that was on that portion of the disk before the write operations.
Most computer disk drives are not considered stable storage because they do not guarantee atomic write; an error could be returned upon subsequent read of the disk where it was just written to in lieu of either the new or prior data.
Implementation
Multiple techniques have been developed to achieve the atomic property from weakly atomic devices such as disks. Writing data to a disk in two places in a specific way is one technique and can be done by application software.
Most often though, stable storage functionality is achieved by mirroring data on separate disks via RAID technology (level 1 or greater). The RAID controller implements the disk writing algorithms that enable separate disks to act as stable storage.
The RAID technique is robust against some single disk failure in an array of disks whereas the software technique of writing to separate areas of the same disk only protects against some kinds of internal disk media failures such as bad sectors in single disk arrangements.
Computer data storage |
https://en.wikipedia.org/wiki/Peaucellier%E2%80%93Lipkin%20linkage | The Peaucellier–Lipkin linkage (or Peaucellier–Lipkin cell, or Peaucellier–Lipkin inversor), invented in 1864, was the first true planar straight line mechanism – the first planar linkage capable of transforming rotary motion into perfect straight-line motion, and vice versa. It is named after Charles-Nicolas Peaucellier (1832–1913), a French army officer, and Yom Tov Lipman Lipkin (1846–1876), a Lithuanian Jew and son of the famed Rabbi Israel Salanter.
Until this invention, no planar method existed of converting exact straight-line motion to circular motion, without reference guideways. In 1864, all power came from steam engines, which had a piston moving in a straight-line up and down a cylinder. This piston needed to keep a good seal with the cylinder in order to retain the driving medium, and not lose energy efficiency due to leaks. The piston does this by remaining perpendicular to the axis of the cylinder, retaining its straight-line motion. Converting the straight-line motion of the piston into circular motion was of critical importance. Most, if not all, applications of these steam engines, were rotary.
The mathematics of the Peaucellier–Lipkin linkage is directly related to the inversion of a circle.
Earlier Sarrus linkage
There is an earlier straight-line mechanism, whose history is not well known, called the Sarrus linkage. This linkage predates the Peaucellier–Lipkin linkage by 11 years and consists of a series of hinged rectangular plates, two of which remain parallel but can be moved normally to each other. Sarrus' linkage is of a three-dimensional class sometimes known as a space crank, unlike the Peaucellier–Lipkin linkage which is a planar mechanism.
Geometry
In the geometric diagram of the apparatus, six bars of fixed length can be seen: , , , , , . The length of is equal to the length of , and the lengths of , , , and are all equal forming a rhombus. Also, point is fixed. Then, if point is constrained to move along a circle (for exampl |
https://en.wikipedia.org/wiki/Ultimopharyngeal%20body | The ultimopharyngeal body, or ultimobranchial body or ultimobranchial gland is a small organ found in the neck region of many animals. In humans, it develops from the fourth pharyngeal pouch into the parafollicular cells of the thyroid to produce calcitonin. It may not develop in DiGeorge syndrome.
Structure
The ultimopharyngeal body is a small organ of the neck. It is found in many animals. In humans, it develops into other tissues.
Development
In humans, the ultimopharyngeal body is an embryological structure, and is a derivative of the ventral recess of the fourth pharyngeal pouch. It is technically from the fifth pharyngeal pouch, but this is rudimentary and merges with the fourth. It develops into the parafollicular cells of the thyroid. The cells that give rise to the parafollicular cells are derivatives of endoderm. Endoderm cells migrate and associate with the ultimopharyngeal body during development.
Function
In humans, the ultimopharyngeal body develops into the parafollicular cells of the thyroid. These secrete calcitonin. In other animals, the ultimopharyngeal body may produce calcitonin.
Clinical significance
The ultimopharyngeal body may not develop in DiGeorge syndrome.
History
The ultimopharyngeal body may also be known as the ultimobranchial body or the ultimobranchial gland. |
https://en.wikipedia.org/wiki/Cellomics | Cellomics is the discipline of quantitative cell analysis using bioimaging methods and informatics with a workflow involving three major components: image acquisition, image analysis, and data visualization and management. These processes are generally automated. All three of these components depend on sophisticated software to acquire qualitative data, quantitative data, and the management of both images and data, respectively. Cellomics is also a trademarked term, which is often used interchangeably with high-content analysis (HCA) or high-content screening (HCS), but cellomics extends beyond HCA/HCS by incorporating sophisticated informatics tools.
History
HCS and the discipline of cellomics was pioneered by a once privately held company named Cellomics Inc., which commercialized instruments, software, and reagents to facilitate the study of cells in culture, and more specifically, their responses to potentially therapeutic drug-like molecules. In 2005, Cellomics was acquired by Fisher Scientific International, Inc., now Thermo Fisher Scientific, which continues developing cellomics-centered products under its Thermo Scientific™ high content analysis product line.
Applications
Like many of the -omics, e.g., genomics and proteomics, applications have grown in depth and breadth over time. Currently there are over 40 different application areas that cellomics is used in, including the analysis of 3-D cell models, angiogenesis, and cell-signalling. Originally a tool used by the pharmaceutical industry for screening, cellomics has now expanded into academia to better understand cell function in the context of the cell. Cellomics is used in both academic and industrial life-science research in areas, such as cancer research, neuroscience research, drug discovery, consumer products safety, and toxicology; however, there are many more areas for which cellomics could provide a much deeper understanding of cellular function.
Image analysis
With HCA at its core, cello |
https://en.wikipedia.org/wiki/Type%20B%20videotape | 1–inch type B VTR (designated Type B by SMPTE) is a reel-to-reel analog recording video tape format developed by the Bosch Fernseh division of Bosch in Germany in 1976. The magnetic tape format became the broadcasting standard in continental Europe, but adoption was limited in the United States and United Kingdom, where the Type C videotape VTR met with greater success.
Details
The tape speed allowed 96 minutes on a large reel (later 120 minutes), and used 2 record/playback (R/P) heads on the drum rotating at 9,000 RPM with a 190-degree wrap around a very small head drum, recording 52 video lines per head segment. A single video frame or field was recorded across 6 tracks in the tape. The format only allowed for play, rewind and fast forward. Video is recorded on an FM signal with a bandwidth of 5.5 MHz. Three longitudinal audio tracks are recorded on the tape as well: two audio and one Linear timecode (LTC) track. BCN 50 VTRs were used at the 1980 Summer Olympics in Moscow.
The format required an optional, and costly, digital framestore in addition to the normal analog timebase corrector to do any "trick-play" operations, such as slow motion/variable-speed playback, frame step play, and visible shuttle functions. This was because, unlike 1-inch type C which recorded one field per helical scan track on the tape, Type B segmented each field to 5 or 6 tracks per field according to whether it was a 525- (NTSC) or 625- (PAL) line machine.
The picture quality was excellent, and standard R/P machines, digital frame store machines, reel-to-reel portables, random access cart machines (for playback of short-form video material such as television commercials), and portable cart versions were marketed.
Echo Science Corporation, a United States company, made units like a BCN 1 for the U.S. military for a short time in the 1970s. Echo Science models were Pilot 1, Echo 460, Pilot 260.
Models introduced
BCR (BCR-40, BCR-50 and BCR-60) was a pre BCN VTR, made jointly with Phil |
https://en.wikipedia.org/wiki/State%20Research%20Center%20of%20Virology%20and%20Biotechnology%20VECTOR | The State Research Center of Virology and Biotechnology VECTOR, also known as the Vector Institute (), is a biological research center in Koltsovo, Novosibirsk Oblast, Russia. It has research facilities and capabilities for all levels of biological hazard, CDC levels 1–4. It is one of two official repositories for the now-eradicated smallpox virus, and was part of the system of laboratories known as the Biopreparat.
The facility was upgraded and secured using modern cameras, motion sensors, fences and biohazard containment systems. Its relative seclusion makes security an easier task. Since its inception there has been an army regiment guarding the facility.
At least in Soviet times the facility was a nexus for biological warfare research (see Soviet biological weapons program), though the nature of any ongoing research in this area is uncertain.
As of April 2022 the Vector Institute is the Russian site for the WHO H5 Reference Laboratory Network, which responds "to the public health needs arising from avian influenza A(H5N1) infection in humans and influenza pandemic preparedness."
History
Organized in 1974, the center has a long history of virology, making impressive Soviet contribution to smallpox research. Genetic engineering projects included creation of viruses that manufacture toxins as well as research on bioregulators and various peptides that function in the nervous system. In the post-Soviet times the center made research and development contributions in many projects like a vaccine for Hepatitis A, influenza vaccines, vaccines for the Ebola virus, antiviral drugs with nucleotide analogs, test-systems for diagnostics of HIV and Hepatitis B and other development. It is one of the two laboratories worldwide that are authorized to keep smallpox.
COVID-19 vaccine development
In March 2020 it was reported that Russian scientists have begun to test vaccine prototypes for the new coronavirus disease (COVID-19), with the plan of presenting the most effect |
https://en.wikipedia.org/wiki/Hilbert%27s%20twelfth%20problem | Hilbert's twelfth problem is the extension of the Kronecker–Weber theorem on abelian extensions of the rational numbers, to any base number field. It is one of the 23 mathematical Hilbert problems and asks for analogues of the roots of unity that generate a whole family of further number fields, analogously to the cyclotomic fields and their subfields. Leopold Kronecker described the complex multiplication issue as his , or "dearest dream of his youth", so the problem is also known as Kronecker's Jugendtraum.
The classical theory of complex multiplication, now often known as the , does this for the case of any imaginary quadratic field, by using modular functions and elliptic functions chosen with a particular period lattice related to the field in question. Goro Shimura extended this to CM fields. In the special case of totally real fields, Samit Dasgupta and Mahesh Kakde provided a construction of the maximal abelian extension of totally real fields using the Brumer–Stark conjecture.
The general case of Hilbert's twelfth problem is still open .
Description of the problem
The fundamental problem of algebraic number theory is to describe the fields of algebraic numbers. The work of Galois made it clear that field extensions are controlled by certain groups, the Galois groups. The simplest situation, which is already at the boundary of what is well understood, is when the group in question is abelian. All quadratic extensions, obtained by adjoining the roots of a quadratic polynomial, are abelian, and their study was commenced by Gauss. Another type of abelian extension of the field Q of rational numbers is given by adjoining the nth roots of unity, resulting in the cyclotomic fields. Already Gauss had shown that, in fact, every quadratic field is contained in a larger cyclotomic field. The Kronecker–Weber theorem shows that any finite abelian extension of Q is contained in a cyclotomic field. Kronecker's (and Hilbert's) question addresses the situation of a mor |
https://en.wikipedia.org/wiki/Mathemagician | A mathemagician is a mathematician who is also a magician. The term "mathemagic" is believed to have been introduced by Royal Vale Heath with his 1933 book "Mathemagic".
The name "mathemagician" was probably first applied to Martin Gardner, but has since been used to describe many mathematician/magicians, including Arthur T. Benjamin, Persi Diaconis, and Colm Mulcahy. Diaconis has suggested that the reason so many mathematicians are magicians is that "inventing a magic trick and inventing a theorem are very similar activities."
Mathemagician is a neologism, specifically a portmanteau, that combines mathematician and magician. A great number of self-working mentalism tricks rely on mathematical principles. Max Maven often utilizes this type of magic in his performance.
The Mathemagician is the name of a character in the 1961 children's book The Phantom Tollbooth. He is the ruler of Digitopolis, the kingdom of mathematics.
Notable mathemagicians
Arthur T. Benjamin
Jin Akiyama
Persi Diaconis
Richard Feynman
Karl Fulves
Martin Gardner
Ronald Graham
Royal Vale Heath
Colm Mulcahy
Raymond Smullyan
W. W. Rouse Ball
Alex Elmsley |
https://en.wikipedia.org/wiki/Homological%20mirror%20symmetry | Homological mirror symmetry is a mathematical conjecture made by Maxim Kontsevich. It seeks a systematic mathematical explanation for a phenomenon called mirror symmetry first observed by physicists studying string theory.
History
In an address to the 1994 International Congress of Mathematicians in Zürich, speculated that mirror symmetry for a pair of Calabi–Yau manifolds X and Y could be explained as an equivalence of a triangulated category constructed from the algebraic geometry of X (the derived category of coherent sheaves on X) and another triangulated category constructed from the symplectic geometry of Y (the derived Fukaya category).
Edward Witten originally described the topological twisting of the N=(2,2) supersymmetric field theory into what he called the A and B model topological string theories. These models concern maps from Riemann surfaces into a fixed target—usually a Calabi–Yau manifold. Most of the mathematical predictions of mirror symmetry are embedded in the physical equivalence of the A-model on Y with the B-model on its mirror X. When the Riemann surfaces have empty boundary, they represent the worldsheets of closed strings. To cover the case of open strings, one must introduce boundary conditions to preserve the supersymmetry. In the A-model, these boundary conditions come in the form of Lagrangian submanifolds of Y with some additional structure (often called a brane structure). In the B-model, the boundary conditions come in the form of holomorphic (or algebraic) submanifolds of X with holomorphic (or algebraic) vector bundles on them. These are the objects one uses to build the relevant categories. They are often called A and B branes respectively. Morphisms in the categories are given by the massless spectrum of open strings stretching between two branes.
The closed string A and B models only capture the so-called topological sector—a small portion of the full string theory. Similarly, the branes in these models are only topologic |
https://en.wikipedia.org/wiki/Dip-pen%20nanolithography | Dip pen nanolithography (DPN) is a scanning probe lithography technique where an atomic force microscope (AFM) tip is used to create patterns directly on a range of substances with a variety of inks. A common example of this technique is exemplified by the use of alkane thiolates to imprint onto a gold surface. This technique allows surface patterning on scales of under 100 nanometers. DPN is the nanotechnology analog of the dip pen (also called the quill pen), where the tip of an atomic force microscope cantilever acts as a "pen," which is coated with a chemical compound or mixture acting as an "ink," and put in contact with a substrate, the "paper."
DPN enables direct deposition of nanoscale materials onto a substrate in a flexible manner. Recent advances have demonstrated massively parallel patterning using two-dimensional arrays of 55,000 tips.
Applications of this technology currently range through chemistry, materials science, and the life sciences, and include such work as ultra high density biological nanoarrays, and additive photomask repair.
Development
The uncontrollable transfer of a molecular 'ink' from a coated AFM tip to a substrate was first reported by Jaschke and Butt in 1995, but they erroneously concluded that alkanethiols could not be transferred to gold substrates to form stable nanostructures. A research group at Northwestern University, US led by Chad Mirkin independently studied the process and determined that under the appropriate conditions, molecules could be transferred to a wide variety of surfaces to create stable chemically-adsorbed monolayers in a high resolution lithographic process they termed "DPN". Mirkin and his coworkers hold the patents on this process, and the patterning technique has expanded to include liquid "inks". It is important to note that "liquid inks" are governed by a very different deposition mechanism when compared to "molecular inks".
Deposition materials
Molecular inks
Molecular inks are typically co |
https://en.wikipedia.org/wiki/Columbia%20%28personification%29 | Columbia (; ), also known as Miss Columbia, is a female national personification of the United States. It was also a historical name applied to the Americas and to the New World. The association has given rise to the names of many American places, objects, institutions and companies, including the District of Columbia; Columbia, South Carolina; Columbia University; "Hail, Columbia"; Columbia Rediviva; and the Columbia River. Images of the Statue of Liberty (Liberty Enlightening the World, erected in 1886) largely displaced personified Columbia as the female symbol of the United States by around 1920, although Lady Liberty was seen as an aspect of Columbia. Columbia's most prominent display in the 21st Century is as part of the logo of the Hollywood film studio Columbia Pictures.
Columbia is a Neo-Latin toponym, in use since the 1730s with reference to the Thirteen Colonies which formed the United States. It originated from the name of the Genoese explorer Christopher Columbus and from the Latin ending -ia, common in the Latin names of countries (paralleling Britannia, Gallia, Zealandia, and others).
Appearance
Columbia is usually depicted unaccompanied in illustrations and appears as a goddess-like human. She is portrayed with auburn, brown, and sometimes black hair, usually wears simple white garment, draped in the American flag, or wearing some other dress with different colors. She is often illustrated with a liberty cap and holding an American flag, and sometimes wielding a shield with the coat of arms of the United States on it. She is also known as "Miss Columbia", implying that she is unmarried.
History
Early
The earliest type of personification of the Americas, seen in European art from the 16th century onwards, reflected the tropical regions in South and Central America from which the earliest European travelers reported back. Such images were most often used in sets of female personifications of the four continents. America was depicted as a woman w |
https://en.wikipedia.org/wiki/Truth-value%20semantics | In formal semantics, truth-value semantics is an alternative to Tarskian semantics. It has been primarily championed by Ruth Barcan Marcus, H. Leblanc, and J. Michael Dunn and Nuel Belnap. It is also called the substitution interpretation (of the quantifiers) or substitutional quantification.
The idea of these semantics is that a universal (respectively, existential) quantifier may be read as a conjunction (respectively, disjunction) of formulas in which constants replace the variables in the scope of the quantifier. For example, may be read () where are individual constants replacing all occurrences of in .
The main difference between truth-value semantics and the standard semantics for predicate logic is that there are no domains for truth-value semantics. Only the truth clauses for atomic and for quantificational formulas differ from those of the standard semantics. Whereas in standard semantics atomic formulas like or are true if and only if (the referent of) is a member of the extension of the predicate , respectively, if and only if the pair is a member of the extension of , in truth-value semantics the truth-values of atomic formulas are basic. A universal (existential) formula is true if and only if all (some) substitution instances of it are true. Compare this with the standard semantics, which says that a universal (existential) formula is true if and only if for all (some) members of the domain, the formula holds for all (some) of them; for example, is true (under an interpretation) if and only if for all in the domain , is true (where is the result of substituting for all occurrences of in ). (Here we are assuming that constants are names for themselves—i.e. they are also members of the domain.)
Truth-value semantics is not without its problems. First, the strong completeness theorem and compactness fail. To see this consider the set . Clearly the formula is a logical consequence of the set, but it is not a consequence of any finite subs |
https://en.wikipedia.org/wiki/King%27s%20American%20Dispensatory | King's American Dispensatory is a book first published in 1854 that covers the uses of herbs used in American medical practice, especially by those involved in eclectic medicine, which was the botanical school of medicine in the 19th to 20th centuries. In 1880 John Uri Lloyd, an eclectic pharmacist of the late 19th and early 20th centuries, promised his friend, professor John King, to revise the pharmaceutical and chemical sections of the American Dispensatory. Eighteen years later an entirely rewritten eighteenth edition (third revision) was published in 1898. It was co-authored by eclectic physician Harvey Wickes Felter
External links
Kings American Dispensatory, 1905 edition at the Internet Archive
1854 books
1898 books
Eclectic medicine
Health and wellness books
Herbalism
Pharmacology literature |
https://en.wikipedia.org/wiki/Gel%20extraction | In molecular biology, gel extraction or gel isolation is a technique used to isolate a desired fragment of intact DNA from an agarose gel following agarose gel electrophoresis. After extraction, fragments of interest can be mixed, precipitated, and enzymatically ligated together in several simple steps. This process, usually performed on plasmids, is the basis for rudimentary genetic engineering.
After DNA samples are run on an agarose gel, extraction involves four basic steps: identifying the fragments of interest, isolating the corresponding bands, isolating the DNA from those bands, and removing the accompanying salts and stain.
To begin, UV light is shone on the gel in order to illuminate all the ethidium bromide-stained DNA. Care must be taken to avoid exposing the DNA to mutagenic radiation for longer than absolutely necessary. The desired band is identified and physically removed with a cover slip or razor blade. The removed slice of gel should contain the desired DNA inside. An alternative method, utilizing SYBR Safe DNA gel stain and blue-light illumination, avoids the DNA damage associated with ethidium bromide and UV light.
Several strategies for isolating and cleaning the DNA fragment of interest exist.
Spin Column Extraction
Gel extraction kits are available from several major biotech manufacturers for a final cost of approximately 1–2 US$ per sample.
Protocols included in these kits generally call for the dissolution of the gel-slice in 3 volumes of chaotropic agent at 50 °C, followed by application of the solution to a spin-column (the DNA remains in the column), a 70% ethanol wash (the DNA remains in the column, salt and impurities are washed out), and elution of the DNA in a small volume (30 µL) of water or buffer.
Dialysis
The gel fragment is placed in a dialysis tube that is permeable to fluids but impermeable to molecules at the size of DNA, thus preventing the DNA from passing through the membrane when soaked in TE buffer. An electric f |
https://en.wikipedia.org/wiki/Snag%20%28ecology%29 | In forest ecology, a snag refers to a standing, dead or dying tree, often missing a top or most of the smaller branches. In freshwater ecology it refers to trees, branches, and other pieces of naturally occurring wood found sunken in rivers and streams; it is also known as coarse woody debris. Snags provide habitat for a wide variety of wildlife but pose hazards to river navigation. When used in manufacturing, especially in Scandinavia, they are often called dead wood and in Finland, kelo wood.
Forest snags
Snags are an important structural component in forest communities, making up 10–20% of all trees present in old-growth tropical, temperate, and boreal forests. Snags and downed coarse woody debris represent a large portion of the woody biomass in a healthy forest.
In temperate forests, snags provide critical habitat for more than 100 species of bird and mammal, and snags are often called 'wildlife trees' by foresters. Dead, decaying wood supports a rich community of decomposers like bacteria and fungi, insects, and other invertebrates. These organisms and their consumers, along with the structural complexity of cavities, hollows, and broken tops make snags important habitat for birds, bats, and small mammals, which in turn feed larger mammalian predators.
Snags are optimal habitat for primary cavity nesters such as woodpeckers which create the majority of cavities used by secondary cavity users in forest ecosystems. Woodpeckers excavate cavities for more than 80 other species and the health of their populations relies on snags. Most snag-dependent birds and mammals are insectivorous and represent a major portion of the insectivorous forest fauna, and are important factors in controlling forest insect populations. There are many instances in which birds reduced outbreak populations of forest insects, such as woodpeckers affecting outbreaks of southern hardwood borers and Engelmann spruce beetles.
Snag creation occurs naturally as trees die due to old age, di |
https://en.wikipedia.org/wiki/Polytomous%20Rasch%20model | The polytomous Rasch model is generalization of the dichotomous Rasch model. It is a measurement model that has potential application in any context in which the objective is to measure a trait or ability through a process in which responses to items are scored with successive integers. For example, the model is applicable to the use of Likert scales, rating scales, and to educational assessment items for which successively higher integer scores are intended to indicate increasing levels of competence or attainment.
Background and overview
The polytomous Rasch model was derived by Andrich (1978), subsequent to derivations by Rasch (1961) and Andersen (1977), through resolution of relevant terms of a general form of Rasch's model into threshold and discrimination parameters. When the model was derived, Andrich focused on the use of Likert scales in psychometrics, both for illustrative purposes and to aid in the interpretation of the model.
The model is sometimes referred to as the Rating Scale Model when (i) items have the same number of thresholds and (ii) in turn, the difference between any given threshold location and the mean of the threshold locations is equal or uniform across items. This is, however, a potentially misleading name for the model because it is far more general in its application than to so-called rating scales. The model is also sometimes referred to as the Partial Credit Model, particularly when applied in educational contexts. The Partial Credit Model (Masters, 1982) has an identical algebraic form but was derived from a different starting point at a later time, and is interpreted in a somewhat different manner. The Partial Credit Model also allows different thresholds for different items. Although this name for the model is often used, Andrich (2005) provides a detailed analysis of problems associated with elements of Masters' approach, which relate specifically to the type of response process that is compatible with the model, and to |
https://en.wikipedia.org/wiki/Depth%20of%20focus | Depth of focus is a lens optics concept that measures the tolerance of placement of the image plane (the film plane in a camera) in relation to the lens. In a camera, depth of focus indicates the tolerance of the film's displacement within the camera and is therefore sometimes referred to as "lens-to-film tolerance".
Depth of focus versus depth of field
The phrase depth of focus is sometimes erroneously used to refer to the depth of field (DOF), which is the area in front of the lens in acceptable focus, whereas the true meaning of depth of focus refers to the zone behind the lens wherein the film plane or sensor is placed to produce an in-focus image.
Depth of focus can have two slightly different meanings. The first is the distance over which the image plane can be displaced while a single object plane remains in acceptably sharp focus; the second is the image-side conjugate of depth of field. With the first meaning, the depth of focus is symmetrical about the image plane; with the second, the depth of focus is greater on the far side of the image plane, though in most cases the distances are approximately equal.
Where depth of field often can be measured in macroscopic units such as meters and feet, depth of focus is typically measured in microscopic units such as fractions of a millimeter or thousandths of an inch.
The same factors that determine depth of field also determine depth of focus, but these factors can have different effects than they have in depth of field. Both depth of field and depth of focus increase with smaller apertures. For distant subjects (beyond macro range), depth of focus is relatively insensitive to focal length and subject distance, for a fixed f-number. In the macro region, depth of focus increases with longer focal length or closer subject distance, while depth of field decreases.
Determining factors
In small-format cameras, the smaller circle of confusion limit yields a proportionately smaller depth of focus. In motion-picture |
https://en.wikipedia.org/wiki/Alexander%20Monro%20Primus | Alexander Monro (19 September 169710 July 1767) was a Scottish surgeon and anatomist. His father, the surgeon John Monro, had been a prime mover in the foundation of the Edinburgh Medical School and had arranged Alexander's education in the hope that his son might become the first Professor of Anatomy in the new university medical school.
After medical studies in Edinburgh, London, Paris and Leiden, Alexander Monro returned to Edinburgh, and pursued a career as a surgeon and anatomy teacher. With the support of his father and the patronage of the Edinburgh, Lord Provost George Drummond, Alexander Monro was appointed foundation Professor of Anatomy at the University of Edinburgh. His lectures, delivered in English, rather than the conventional Latin, proved popular with students and his qualities as a teacher contributed to the success and reputation of the Edinburgh medical school.
He is known as Alexander Monro Primus or Senior to distinguish him from his son Alexander Monro ("Secundus") and his grandson Alexander Monro ("Tertius") who both followed him in the chair of anatomy. These three Monros between them held the Edinburgh University Chair of Anatomy for 126 years.
Early life and education
Alexander Monro was the son of John Monro and his wife, Jean Forbes, who was his first cousin. John Monro was a Monro of Auchenbowie, a cadet branch of Clan Munro, descended from the Monros of Foulis.
John Monro was a military surgeon and his son Alexander was born in London while he was on military duty there. When Alexander was three the family returned to Edinburgh, where John Monro took great care with his son's education. He had him instructed in Latin, Greek and French, and in philosophy, arithmetic and book-keeping.
Alexander attended classes at the University of Edinburgh between 1710 and 1713 but did not graduate.
He was then bound apprentice to his father, who was by now in practice as a surgeon in Edinburgh. During this apprenticeship he also attended c |
https://en.wikipedia.org/wiki/Thomas%20Kailath | Thomas Kailath (born June 7, 1935) is an Indian born American electrical engineer, information theorist, control engineer, entrepreneur and the Hitachi America Professor of Engineering emeritus at Stanford University. Professor Kailath has authored several books, including the well-known book Linear Systems, which ranks as one of the most referenced books in the field of linear systems.
Kailath was elected as a member into the US National Academy of Engineering in 1984 for outstanding contributions in prediction, filtering, and signal processing, and for leadership in engineering.
In 2012, Kailath was awarded the National Medal of Science, presented by President Barack Obama in 2014 for "transformative contributions to the fields of information and system science, for distinctive and sustained mentoring of young scholars, and for translation of scientific ideas into entrepreneurial ventures that have had a significant impact on industry."
Kailath is listed as an ISI highly cited researcher and is generally recognized as one of the preeminent figures of twentieth-century electrical engineering.
Biography
Kailath was born in 1935 in Pune, Maharashtra, India, to a Malayalam-speaking Syrian Christian family named Chittoor. His parents hailed from Kerala. He studied at St. Vincent's High School, Pune and received his engineering Bachelor's degree from the Government College of Engineering, the University of Pune in 1956. He received his Master's degree in 1959 and his doctorate degree in 1961, both from the Massachusetts Institute of Technology (MIT). He was the first Indian-born student to receive a doctorate in electrical engineering from MIT.
Kailath is Hitachi America Professor of Engineering emeritus at Stanford University. Here he has supervised about 80 Ph.D. theses. Kailath's research work has encompassed linear systems, estimation and control theory, signal processing, information theory and semiconductor device fabrication.
Kailath has been an Institute o |
https://en.wikipedia.org/wiki/Shape%20resonance | A shape resonance is a metastable state in which an electron is trapped due to the shape of a potential barrier.
Altunata describes a state as being a shape resonance if, "the internal state of the system remains unchanged upon disintegration of the quasi-bound level."
A more general discussion of resonances and their taxonomies in molecular system can be found in the review article by Schulz,; for the discovery of the Fano resonance line-shape and for the Majorana pioneering work in this field by Antonio Bianconi; and for
a mathematical review by Combes et al.
Quantum mechanics
In quantum mechanics, a shape resonance, in contrast to a Feshbach resonance, is a resonance which is not turned into a bound state if the coupling between some degrees of freedom and the degrees of freedom associated to the fragmentation (reaction coordinates) are set to zero. More simply, the shape resonance total energy is more than the separated fragment energy.
Practical implications of this difference for lifetimes and spectral widths are mentioned in works such as Zobel.
Related terms include a special kind of shape resonance, the core-excited shape resonance, and trap-induced shape resonance.
Of course in one-dimensional systems, resonances are shape resonances. In a system with more than one degree of freedom, this definition makes sense only if the separable model, which supposes the two groups of degrees of freedom uncoupled, is a meaningful approximation. When the coupling becomes large, the situation is much less clear.
In the case of atomic and molecular electronic structure problems, it is well known that the self-consistent field (SCF) approximation is relevant at least as a starting point of more elaborate methods. The Slater determinants built from SCF orbitals (atomic or molecular orbitals) are shape resonances if only one electronic transition is required to emit one electron.
Today, there is some debate about the definition and even existence of the shape resona |
https://en.wikipedia.org/wiki/Core-excited%20shape%20resonance | A core-excited shape resonance is a shape resonance in a system with more than one degree of freedom where, after fragmentation, one of the fragments is in an excited state. It is sometimes very difficult to distinguish a core-excited shape resonance from a Feshbach resonance.
See also
See the definition of Feshbach resonances for more details.
External links
A short FAQ on quantum resonances
Scattering |
https://en.wikipedia.org/wiki/Empty%20domain | In first-order logic the empty domain is the empty set having no members. In traditional and classical logic domains are restrictedly non-empty in order that certain theorems be valid. Interpretations with an empty domain are shown to be a trivial case by a convention originating at least in 1927 with Bernays and Schönfinkel (though possibly earlier) but oft-attributed to Quine 1951. The convention is to assign any formula beginning with a universal quantifier the value truth while any formula beginning with an existential quantifier is assigned the value falsehood. This follows from the idea that existentially quantified statements have existential import (i.e. they imply the existence of something) while universally quantified statements do not. This interpretation reportedly stems from George Boole in the late 19th century but this is debatable. In modern model theory, it follows immediately for the truth conditions for quantified sentences:
In other words, an existential quantification of the open formula φ is true in a model iff there is some element in the domain (of the model) that satisfies the formula; i.e. iff that element has the property denoted by the open formula. A universal quantification of an open formula φ is true in a model iff every element in the domain satisfies that formula. (Note that in the metalanguage, "everything that is such that X is such that Y" is interpreted as a universal generalization of the material conditional "if anything is such that X then it is such that Y". Also, the quantifiers are given their usual objectual readings, so that a positive existential statement has existential import, while a universal one does not.) An analogous case concerns the empty conjunction and the empty disjunction. The semantic clauses for, respectively, conjunctions and disjunctions are given by
.
It is easy to see that the empty conjunction is trivially true, and the empty disjunction trivially false.
Logics whose theorems are valid in every |
https://en.wikipedia.org/wiki/Class-D%20amplifier | A class-D amplifier or switching amplifier is an electronic amplifier in which the amplifying devices (transistors, usually MOSFETs) operate as electronic switches, and not as linear gain devices as in other amplifiers. They operate by rapidly switching back and forth between the supply rails, using pulse-width modulation, pulse-density modulation, or related techniques to produce a pulse train output. This passes through a simple low-pass filter which blocks the high-frequency pulses and provides analog output current and voltage. Because they are always either in fully on or fully off modes, little energy is dissipated in the transistors and efficiency can exceed 90%.
History
The first Class-D amplifier was invented by British scientist Alec Reeves in the 1950s and was first called by that name in 1955. The first commercial product was a kit module called the X-10 released by Sinclair Radionics in 1964. However, it had an output power of only 2.5 watts. The Sinclair X-20 in 1966 produced 20 watts but suffered from the inconsistencies and limitations of the germanium-based bipolar junction transistors available at the time. As a result, these early class-D amplifiers were impractical and unsuccessful. Practical class-D amplifiers were enabled by the development of silicon-based MOSFET (metal–oxide–semiconductor field-effect transistor) technology. In 1978, Sony introduced the TA-N88, the first class-D unit to employ power MOSFETs and a switched-mode power supply. There were subsequently rapid developments in MOSFET technology between 1979 and 1985. The availability of low-cost, fast-switching MOSFETs led to Class-D amplifiers becoming successful in the mid-1980s. The first class-D amplifier based integrated circuit was released by Tripath in 1996, and it saw widespread use.
Basic operation
Class-D amplifiers work by generating a train of rectangular pulses of fixed amplitude but varying width and separation. This modulation represents the amplitude variations |
https://en.wikipedia.org/wiki/Fano%20resonance | In physics, a Fano resonance is a type of resonant scattering phenomenon that gives rise to an asymmetric line-shape. Interference between a background and a resonant scattering process produces the asymmetric line-shape. It is named after Italian-American physicist Ugo Fano, who in 1961 gave a theoretical explanation for the scattering line-shape of inelastic scattering of electrons from helium; however, Ettore Majorana was the first to discover this phenomenon. Fano resonance is a weak coupling effect meaning that the decay rate is so high, that no hybridization occurs. The coupling modifies the resonance properties such as spectral position and width and its line-shape takes on the distinctive asymmetric Fano profile. Because it is a general wave phenomenon, examples can be found across many areas of physics and engineering.
History
The explanation of the Fano line-shape first appeared in the context of inelastic electron scattering by helium and autoionization. The incident electron doubly excites the atom to the state, a sort of shape resonance. The doubly excited atom spontaneously decays by ejecting one of the excited electrons. Fano showed that interference between the amplitude to simply scatter the incident electron and the amplitude to scatter via autoionization creates an asymmetric scattering line-shape around the autoionization energy with a line-width very close to the inverse of the autoionization lifetime.
Explanation
The Fano resonance line-shape is due to interference between two scattering amplitudes, one due to scattering within a continuum of states (the background process) and the second due to an excitation of a discrete state (the resonant process). The energy of the resonant state must lie in the energy range of the continuum (background) states for the effect to occur. Near the resonant energy, the background scattering amplitude typically varies slowly with energy while the resonant scattering amplitude changes both in magnitude and |
https://en.wikipedia.org/wiki/Meibomian%20gland | Meibomian glands (also called tarsal glands, palpebral glands, and tarsoconjunctival glands) are sebaceous glands along the rims of the eyelid inside the tarsal plate. They produce meibum, an oily substance that prevents evaporation of the eye's tear film. Meibum prevents tears from spilling onto the cheek, traps them between the oiled edge and the eyeball, and makes the closed lids airtight. There are about 25 such glands on the upper eyelid, and 20 on the lower eyelid.
Dysfunctional meibomian glands is believed to be the most often cause of dry eyes. They are also the cause of posterior blepharitis.
History
The glands were mentioned by Galen in 200 AD and were described in more detail by Heinrich Meibom (1638–1700), a German physician, in his work De Vasis Palpebrarum Novis Epistola in 1666. This work included a drawing with the basic characteristics of the glands.
Anatomy
Although the upper lid have greater number and volume of meibomian glands than the lower lid, there is no consensus whether it contributes more to the tearfilm stability. The glands do not have direct contact with eyelash follicles. The process of blinking releases meibum into the lid margin.
Function
Meibum
Lipids
Lipids are the major components of meibum (also known as "meibomian gland secretions"). The term "meibum" was originally introduced by Nicolaides et al. in 1981.
The biochemical composition of meibum is extremely complex and very different from that of sebum. Lipids are universally recognized as major components of human and animal meibum. An update was published in 2009 on the composition of human meibum and on the structures of various positively identified meibomian lipids
Currently, the most sensitive and informative approach to lipidomic analysis of meibum is mass spectrometry, either with direct infusion or in combination with liquid chromatography.
The lipids are the main component of the lipid layer of the tear film, preventing rapid evaporation and it is believed |
https://en.wikipedia.org/wiki/Longest%20common%20substring | In computer science, a longest common substring of two or more strings is a longest string that is a substring of all of them. There may be more than one longest common substring. Applications include data deduplication and plagiarism detection.
Examples
The picture shows two strings where the problem has multiple solutions. Although the substring occurrences always overlap, no longer common substring can be obtained by "uniting" them.
The strings "ABABC", "BABCA" and "ABCBA" have only one longest common substring, viz. "ABC" of length 3. Other common substrings are "A", "AB", "B", "BA", "BC" and "C".
ABABC
|||
BABCA
|||
ABCBA
Problem definition
Given two strings, of length and of length , find a longest string which is substring of both and .
A generalization is the k-common substring problem. Given the set of strings , where and . Find for each , a longest string which occurs as substring of at least strings.
Algorithms
One can find the lengths and starting positions of the longest common substrings of and in time with the help of a generalized suffix tree. A faster algorithm can be achieved in the word RAM model of computation if the size of the input alphabet is in . In particular, this algorithm runs in time using space. Solving the problem by dynamic programming costs . The solutions to the generalized problem take space and ·...· time with dynamic programming and take time with a generalized suffix tree.
Suffix tree
The longest common substrings of a set of strings can be found by building a generalized suffix tree for the strings, and then finding the deepest internal nodes which have leaf nodes from all the strings in the subtree below it. The figure on the right is the suffix tree for the strings "ABAB", "BABA" and "ABBA", padded with unique string terminators, to become "ABAB$0", "BABA$1" and "ABBA$2". The nodes representing "A", "B", "AB" and "BA" all have descendant leaves from all of the strings, numbered 0, |
https://en.wikipedia.org/wiki/Yellowhead%20disease | Yellowhead disease (YHD) is a viral infection of shrimp and prawn, in particular of the giant tiger prawn (Penaeus monodon), one of the two major species of farmed shrimp. The disease is caused by the Yellow head virus genotype 1 (YHV1), a positive-strand RNA virus related to coronaviruses and arteriviruses.
The disease is highly lethal and contagious, killing shrimp quickly. Outbreaks of this disease have wiped out in a matter of days the entire populations of many shrimp farms that cultivated P. monodon, i.e. particularly Southeast Asian farms. In Thai, the disease is called . A closely related virus is the Gill-associated virus (GAV).
Clinical
The cephalothorax of infected shrimp turns yellow after a period of unusually high feeding activity ending abruptly, and the then moribund shrimps congregate near the surface of their pond before dying. YHD leads to death of the animals within two to four days.
History
YHD had been reported first from Thailand in 1990, the closely related GAV has been discovered in 1995 during a yellowhead-like disease in Australian shrimp farms. |
https://en.wikipedia.org/wiki/Dynamic%20multipathing | In computer data storage technology field, dynamic multipathing (DMP) is a multipath I/O enhancement technique that balances input/output (I/O) across many available paths from the computer to the storage device to improve performance and availability. The name was introduced with Veritas Volume Manager software.
The DMP utility does not take any time to switch over, although the total time for failover is dependent on how long the underlying disk driver retries the command before giving up.
External links
Veritas - DMP white paper
Computer storage technologies |
https://en.wikipedia.org/wiki/Lanthanide%20contraction | The lanthanide contraction is the greater-than-expected decrease in atomic radii and ionic radii of the elements in the lanthanide series, from left to right. It is caused by the poor shielding effect of nuclear charge by the 4f electrons along with the expected periodic trend of increasing electronegativity and nuclear charge on moving from left to right. About 10% of the lanthanide contraction has been attributed to relativistic effects.
This effect occurs from atomic number 57, lanthanum, to 71, lutetium resulting in smaller than otherwise expected atomic radii and ionic radii for the subsequent elements starting with 72, hafnium. This effect causes the radii of transition metals of group 5 and 6 to become unusually similar and has many other far ranging consequence in post-lanthanide elements.
The decrease in ionic radii (Ln3+) is much more uniform compared to decrease in atomic radii.
The term was coined by the Norwegian geochemist Victor Goldschmidt in his series "Geochemische Verteilungsgesetze der Elemente" (Geochemical distribution laws of the elements).
Cause
The effect results from poor shielding of nuclear charge (nuclear attractive force on electrons) by 4f electrons; the 6s electrons are drawn towards the nucleus, thus resulting in a smaller atomic radius.
In single-electron atoms, the average separation of an electron from the nucleus is determined by the subshell it belongs to, and decreases with increasing charge on the nucleus; this, in turn, leads to a decrease in atomic radius. In multi-electron atoms, the decrease in radius brought about by an increase in nuclear charge is partially offset by increasing electrostatic repulsion among electrons.
In particular, a "shielding effect" operates: i.e., as electrons are added in outer shells, electrons already present shield the outer electrons from nuclear charge, making them experience a lower effective charge on the nucleus. The shielding effect exerted by the inner electrons decreases in |
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