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https://en.wikipedia.org/wiki/Spitzenk%C3%B6rper | The Spitzenkörper (German for 'pointed body', SPK) is a structure found in fungal hyphae that is the organizing center for hyphal growth and morphogenesis. It consists of many small vesicles and is present in growing hyphal tips, during spore germination, and where branch formation occurs. Its position in the hyphal tip correlates with the direction of hyphal growth. The Spitzenkörper is a part of the endomembrane system in fungi.
The vesicles are organized around a central area that contains a dense meshwork of microfilaments. Polysomes are often found closely to the posterior boundary of the Spitzenkörper core within the Ascomycota, microtubules extend into and often through the Spitzenkörper and within the Ascomycota Woronin bodies are found in the apical region near the Spitzenkörper.
The cytoplasm of the extreme apex is occupied almost exclusively by secretory vesicles. In the higher fungi (Ascomycota and Basidiomycota), secretory vesicles are arranged into a dense, spherical aggregation called the Spitzenkörper or ‘apical body’. The Spitzenkörper may be seen in growing hyphae even with a light microscope. Hyphae of the Oomycota and some lower Eumycota (notably the Zygomycota) do not contain a recognizable Spitzenkörper, and the vesicles are instead distributed more loosely often in a crescent-shaped arrangement beneath the apical plasma membrane.
This structure is most commonly found in Dikarya and was at first thought to only occur among them. Vargas et al 1993 however were the first to find a Spitzenkörper in another clade, specifically the Allomyces (Blastocladiomycota), then subsequently Basidiobolus ranarum which has been placed in several different phyla was also found to have an SPK. these and the Blastocladiella (also in Blastocladiomycota) are the only known taxa to bear this structure. |
https://en.wikipedia.org/wiki/Wells%20turbine | The Wells turbine is a low-pressure air turbine that rotates continuously in one direction independent of the direction of the air flow. Its blades feature a symmetrical airfoil with its plane of symmetry in the plane of rotation and perpendicular to the air stream.
It was developed for use in Oscillating Water Column wave power plants, in which a rising and falling water surface moving in an air compression chamber produces an oscillating air current. The use of this bidirectional turbine avoids the need to rectify the air stream by delicate and expensive check valve systems.
Its efficiency is lower than that of a turbine with constant air stream direction and asymmetric airfoil. One reason for the lower efficiency is that symmetric airfoils have a higher drag coefficient than asymmetric ones, even under optimal conditions. Also, in the Wells turbine, the symmetric airfoil runs partly under high angle of attack (i.e., low blade speed / air speed ratio), which occurs during the air velocity maxima of the oscillating flow. A high angle of attack causes a condition known as "stall" in which the airfoil loses lift. The efficiency of the Wells turbine in oscillating flow reaches values between 0.4 and 0.7.
The Wells turbine was developed by Prof. Alan Arthur Wells of Queen's University Belfast in the late 1970s.
Annotation
Another solution of the problem of stream direction independent turbine is the Darrieus wind turbine (Darrieus rotor).
See also
Siadar Wave Energy Project
Yoshio Masuda
Hanna Wave Energy Turbine
free 3D design to print your own
External links
Animation showing OWC wave power plant"
Queen's University Belfast
Mechanical engineering
Turbines
Power station technology
Renewable energy technology
Water power
Electrical generators |
https://en.wikipedia.org/wiki/Field-programmability | An electronic device or embedded system is said to be field-programmable or in-place programmable if its firmware (stored in non-volatile memory, such as ROM) can be modified "in the field", without disassembling the device or returning it to its manufacturer.
This is often an extremely desirable feature, as it can reduce the cost and turnaround time for replacement of buggy or obsolete firmware. For example, a digital camera vendor could distribute firmware supporting a new image file format by instructing consumers to download a new firmware image to the camera via a USB cable.
History
When a device's firmware is stored in mask ROM or one-time programmable PROM, it cannot be modified without physically replacing the integrated circuit, so such a device cannot be field-programmable in the modern sense. Erasable PROM-based firmware can be erased and reprogrammed, but only after lengthy exposure to a high-intensity ultraviolet light source.
Thus, field-programmable devices were not practical until the invention of EEPROM and flash memory in the 1980s. Early EEPROMs could only be reprogrammed with expensive, dedicated programmer hardware, since they required high voltages (10-20 V, compared to typical 3-5 V logic levels) and there was no standard programming protocol; as a result, field-programming was mostly performed by professional technicians and service engineers. However, as of the early 2000s, many devices were expressly designed to be field-programmed by ordinary consumers. Several developments have made this possible:
Modern EEPROM and flash devices contain internal charge pumps which eliminate the need for high voltages.
Most consumers have access to personal computers, which can perform arbitrary programming protocols.
Ubiquitous Internet access provides a convenient means to rapidly distribute firmware images.
Standard protocols for programming non-volatile memory devices have emerged. For example, JTAG may be used to read and program the E |
https://en.wikipedia.org/wiki/National%20Biological%20Information%20Infrastructure | The National Biological Information Infrastructure (NBII) was a program coordinated by the United States Geological Survey's Biological Informatics Office within the USGS Biological Resources Discipline. Its purpose was to facilitate access to data and information on the biological resources of the United States, utilizing government agencies, academic institutions, non-government organizations, and private industry. It was terminated 15 January 2012.
The NBII coordinated the research output of the biological community into information systems that were easily accessed, by providing organization and a structure that was based on standards. The structure was essentially invisible to the end user of the information, but was vitally important to those wishing to participate by making data available through the system, or those who wished to become partners in the development of new tools, models, and applications. The end-user aspect of the NBII was its Web portal which provided access to information, publications, and data from the various data sources "in a seamless, unified portal."
History
The NBII was an outgrowth of a 1993 National Research Council report titled "A Biological Survey for the Nation", which recommended that the United States Department of the Interior oversee the development of a National Biotic Resource Information System to coordinate information about biodiversity and ecosystems. The report found that such information was "vital to a wide range of scientific, educational, and government uses," but that, unfortunately, most of the information existed in forms that were not easily used. It envisioned a system of distributed databases designed to make the existing information more accessible. The report also suggested that new ways to collect and distribute data and information should be developed. It did mention networking, but not the Internet. .
As a first step, in 1994, President Clinton signed Executive Order 12906, "Coordinating Geogra |
https://en.wikipedia.org/wiki/KCNE2 | Potassium voltage-gated channel subfamily E member 2 (KCNE2), also known as MinK-related peptide 1 (MiRP1), is a protein that in humans is encoded by the KCNE2 gene on chromosome 21. MiRP1 is a voltage-gated potassium channel accessory subunit (beta subunit) associated with Long QT syndrome. It is ubiquitously expressed in many tissues and cell types. Because of this and its ability to regulate multiple different ion channels, KCNE2 exerts considerable influence on a number of cell types and tissues. Human KCNE2 is a member of the five-strong family of human KCNE genes. KCNE proteins contain a single membrane-spanning region, extracellular N-terminal and intracellular C-terminal. KCNE proteins have been widely studied for their roles in the heart and in genetic predisposition to inherited cardiac arrhythmias. The KCNE2 gene also contains one of 27 SNPs associated with increased risk of coronary artery disease. More recently, roles for KCNE proteins in a variety of non-cardiac tissues have also been explored.
Discovery
Steve Goldstein (then at Yale University) used a BLAST search strategy, focusing on KCNE1 sequence stretches known to be important for function, to identify related expressed sequence tags (ESTs) in the NCBI database. Using sequences from these ESTs, KCNE2, 3 and 4 were cloned.
Tissue distribution
KCNE2 protein is most readily detected in the choroid plexus epithelium, gastric parietal cells, and thyroid epithelial cells. KCNE2 is also expressed in atrial and ventricular cardiomyocytes, the pancreas, pituitary gland, and lung epithelium. In situ hybridization data suggest that KCNE2 transcript may also be expressed in various neuronal populations.
Structure
Gene
The KCNE2 gene resides on chromosome 21 at the band 21q22.11 and contains 2 exons. Since human KCNE2 is located ~79 kb from KCNE1 and in the opposite direction, KCNE2 is proposed to originate from a gene duplication event.
Protein
This protein belongs to the potassium channel KCNE fa |
https://en.wikipedia.org/wiki/Resonance%20fluorescence | Resonance fluorescence is the process in which a two-level atom system interacts with the quantum electromagnetic field if the field is driven at a frequency near to the natural frequency of the atom.
General theory
Typically the photon contained electromagnetic field is applied to the two-level atom through the use of a monochromatic laser. A two-level atom is a specific type of two-state system in which the atom can be found in the two possible states. The two possible states are if an electron is found in its ground state or the excited state. In many experiments an atom of lithium is used because it can be closely modeled to a two-level atom as the excited states of the singular electron are separated by large enough energy gaps to significantly reduce the possibility of the electron jumping to a higher excited state. Thus it allows for easier frequency tuning of the applied laser as frequencies further off resonance can be used while still driving the electron to jump to only the first excited state. Once the atom is excited, it will release a photon with the same energy as the energy difference between the excited and ground state. The mechanism for this release is the spontaneous decay of the atom. The emitted photon is released in an arbitrary direction. While the transition between two specific energy levels is the dominant mechanism in resonance fluorescence, experimentally other transitions will play a very small role and thus must be taken into account when analyzing results. The other transitions will lead to emission of a photon of a different atomic transition with much lower energy which will lead to "dark" periods of resonance fluorescence.
The dynamics of the electromagnetic field of the monochromatic laser can be derived by first treating the two-level atom as a spin-1/2 system with two energy eigenstates which have energy separation of ħω. The dynamics of the atom can then be described by the three rotation operators, ,,, acting upon the Bloch |
https://en.wikipedia.org/wiki/Davidon%E2%80%93Fletcher%E2%80%93Powell%20formula | The Davidon–Fletcher–Powell formula (or DFP; named after William C. Davidon, Roger Fletcher, and Michael J. D. Powell) finds the solution to the secant equation that is closest to the current estimate and satisfies the curvature condition. It was the first quasi-Newton method to generalize the secant method to a multidimensional problem. This update maintains the symmetry and positive definiteness of the Hessian matrix.
Given a function , its gradient (), and positive-definite Hessian matrix , the Taylor series is
and the Taylor series of the gradient itself (secant equation)
is used to update .
The DFP formula finds a solution that is symmetric, positive-definite and closest to the current approximate value of :
where
and is a symmetric and positive-definite matrix.
The corresponding update to the inverse Hessian approximation is given by
is assumed to be positive-definite, and the vectors and must satisfy the curvature condition
The DFP formula is quite effective, but it was soon superseded by the Broyden–Fletcher–Goldfarb–Shanno formula, which is its dual (interchanging the roles of y and s).
See also
Newton's method
Newton's method in optimization
Quasi-Newton method
Broyden–Fletcher–Goldfarb–Shanno (BFGS) method
Limited-memory BFGS method
Symmetric rank-one formula
Nelder–Mead method |
https://en.wikipedia.org/wiki/Weebly | Weebly is an American web hosting and web development company headquartered in San Francisco and is a subsidiary of Block, Inc. It was founded in 2006 by Chief Executive Officer David Rusenko, Chief Technology Officer Chris Fanini, and former Chief Product Officer Dan Veltri.
History
The company's primary focus was to create software that made it easy for individuals to build personal websites. Formal development of Weebly started in January 2006, with an invitational beta release announced in June 2006 and an official private-beta launch in September 2006.
Throughout its history, Weebly received funding from various investors, including angel investors and venture capital firms. In 2018, co-founder Dan Veltri left the company.
Features
In March 2007, Weebly re-launched with its "WYSIWYG" editing interface, "Pro" accounts and Google AdSense monetization features, as well as compatibility with Google Chrome and Safari. In 2010, the company added French, Italian, Spanish, and Chinese languages, followed by integrated JotForm software into its services. On October 1, 2015, Weebly Carbon was released to allow plugin integration among other features. In 2016, Weebly began focusing on its e-commerce offerings with the release of Weebly 4 and Weebly Promote, an integrated marketing tool.
As more sellers began using the company, the company created features for doing taxes, integrations with Shippo, a Facebook Ad creator, email marketing and lead capture, abandoned cart features, the release of Mobile 5.0 to help sellers run their store from anywhere, and deep integrations with Square payment processing.
Weebly initially faced criticism for its lack of CSS/HTML editing support, but this functionality was added in 2009.
Offices
The company expanded its offices, including a 36,000 square feet warehouse in San Francisco, to accommodate its growing team. Additionally, Weebly opened a Berlin office in 2015/2016 to offer European-based support and marketing.
Acquisition |
https://en.wikipedia.org/wiki/Category%20of%20modules | In algebra, given a ring R, the category of left modules over R is the category whose objects are all left modules over R and whose morphisms are all module homomorphisms between left R-modules. For example, when R is the ring of integers Z, it is the same thing as the category of abelian groups. The category of right modules is defined in a similar way.
One can also define the category of bimodules over a ring R but that category is equivalent to the category of left (or right) modules over the enveloping algebra of R (or over the opposite of that).
Note: Some authors use the term module category for the category of modules. This term can be ambiguous since it could also refer to a category with a monoidal-category action.
Properties
The categories of left and right modules are abelian categories. These categories have enough projectives and enough injectives. Mitchell's embedding theorem states every abelian category arises as a full subcategory of the category of modules of some ring.
Projective limits and inductive limits exist in the categories of left and right modules.
Over a commutative ring, together with the tensor product of modules ⊗, the category of modules is a symmetric monoidal category.
Objects
A monoid object of the category of modules over a commutative ring R is exactly an associative algebra over R.
See also: compact object (a compact object in the R-mod is exactly a finitely presented module).
Category of vector spaces
The category K-Vect (some authors use VectK) has all vector spaces over a field K as objects, and K-linear maps as morphisms. Since vector spaces over K (as a field) are the same thing as modules over the ring K, K-Vect is a special case of R-Mod (some authors use ModR), the category of left R-modules.
Much of linear algebra concerns the description of K-Vect. For example, the dimension theorem for vector spaces says that the isomorphism classes in K-Vect correspond exactly to the cardinal numbers, and that K-Vect i |
https://en.wikipedia.org/wiki/Dorsal%20attention%20network | The dorsal attention network (DAN), also known anatomically as the dorsal frontoparietal network (D-FPN), is a large-scale brain network of the human brain that is primarily composed of the intraparietal sulcus (IPS) and frontal eye fields (FEF). It is named and most known for its role in voluntary orienting of visuospatial attention.
As the IPS and FEF were noticed to be activated during many attention-demanding tasks, this network was sometimes referred to as the task-positive network to contrast it against the task-negative network, or default mode network. However, this dichotomy is now considered misleading, because the default mode network can be active in certain cognitive tasks.
Anatomy
The core regions of the DAN are the IPS and FEF of each hemisphere. Other regions of the network may include the middle temporal region (MT+), superior parietal lobule (SPL), supplementary eye field (SEF), and ventral premotor cortex.
More recent works indicate that the cerebellum may participate in this network as well. Less studied regions include the right dorsolateral prefrontal cortex and superior colliculus.
Function
The DAN is most prominently involved in goal-directed, voluntary control of visuospatial attention. Corbetta et al., who first defined and named the DAN in the early-to-mid 2000s, suggest that the network is involved in general top-down selection of stimuli and responses, including other modalities (e.g. auditory, tactile). However, evidence that the full DAN is involved in auditory top-down attention has been questioned, as tests that make said claims incorporated both auditory and visual stimuli.
The dorsal attention network dynamically interacts with the ventral attention network (or salience network) according to task demands. The inferior frontal junction configures this interaction between the two networks during task switches or attention shifts.
Clinical significance
Reduced connectivity within the dorsal and ventral attention networks has |
https://en.wikipedia.org/wiki/Multimodal%20logic | A multimodal logic is a modal logic that has more than one primitive modal operator. They find substantial applications in theoretical computer science.
Overview
A modal logic with n primitive unary modal operators is called an n-modal logic. Given these operators and negation, one can always add modal operators defined as if and only if .
Perhaps the first substantive example of a two-modal logic is Arthur Prior's tense logic, with two modalities, F and P, corresponding to "sometime in the future" and "sometime in the past". A logic with infinitely many modalities is dynamic logic, introduced by Vaughan Pratt in 1976 and having a separate modal operator for every regular expression. A version of temporal logic introduced in 1977 and intended for program verification has two modalities, corresponding to dynamic logic's [A] and [A*] modalities for a single program A, understood as the whole universe taking one step forwards in time. The term multimodal logic itself was not introduced until 1980. Another example of a multimodal logic is the Hennessy–Milner logic, itself a fragment of the more expressive modal μ-calculus, which is also a fixed-point logic.
Multimodal logic can be used also to formalize a kind of knowledge representation: the motivation of epistemic logic is allowing several agents (they are regarded as subjects capable of forming beliefs, knowledge); and managing the belief or knowledge of each agent, so that epistemic assertions can be formed about them. The modal operator must be capable of bookkeeping the cognition of each agent, thus must be indexed on the set of the agents. The motivation is that should assert "The subject i has knowledge about being true". But it can be used also for formalizing "the subject i believes ". For formalization of meaning based on the possible world semantics approach, a multimodal generalization of Kripke semantics can be used: instead of a single "common" accessibility relation, there is a series of them |
https://en.wikipedia.org/wiki/Ultratrace%20element | In biochemistry, an ultratrace element is a chemical element that normally comprises less than one microgram per gram of a given organism (i.e. less than 0.0001% by weight), but which plays a significant role in its metabolism.
Possible ultratrace elements in humans include boron, silicon, nickel, vanadium and cobalt. Other possible ultratrace elements in other organisms include bromine, cadmium, fluorine, lead, lithium, and tin.
See also
Trace element |
https://en.wikipedia.org/wiki/Allan%E2%80%93Herndon%E2%80%93Dudley%20syndrome | Allan–Herndon–Dudley syndrome is a rare X-linked inherited disorder of brain development that causes both moderate to severe intellectual disability and problems with speech and movement.
Allan–Herndon–Dudley syndrome, which is named eponymously for William Allan, Florence C. Dudley, and C. Nash Herndon, results from a mutation of the thyroid hormone transporter MCT8 (also referred to as SLC16A2). Consequently, thyroid hormones are unable to enter the nervous system, which depends on thyroid signaling for proper function and development.
Signs and symptoms
It is estimated that 80–99% of people with Allan–Herndon–Dudley syndrome will have biparietal narrowing (narrowing of skull), ataxia, abnormalities of the neck, and both absent speech development and aphasia. Weak muscle tone (hypotonia) and underdevelopment of many muscles (muscle hypoplasia) are common in children with Allan–Herndon–Dudley syndrome. Development of joint deformities called contractures, which restrict the movement of certain joints, are common as people age. Mobility is further limited by abnormal muscle stiffness (spasticity), muscle weakness, and involuntary movements of the arms and legs. Many people with Allan–Herndon–Dudley syndrome are unable to walk independently and become wheelchair-reliant by adulthood.
Endocrine phenotype
The typical hormonal signature of AHDS is marked by low free T4 and normal or elevated free T3 concentration, which translates to increased calculated deiodinase activity (SPINA-GD).
Genetics
This condition is inherited in an X-linked recessive pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation must be present in both copies of the gene to cause the disorder. Males are affected by X-linke |
https://en.wikipedia.org/wiki/Population%20vector | In neuroscience, a population vector is the sum of the preferred directions of a population of neurons, weighted by the respective spike counts.
The formula for computing the (normalized) population vector, , takes the following form:
Where is the activity of cell , and is the preferred input for cell .
Note that the vector encodes the input direction, , in terms of the activation of a population of neurons.
Computational neuroscience |
https://en.wikipedia.org/wiki/Mesothelin | Mesothelin, also known as MSLN, is a protein that in humans is encoded by the MSLN gene.
Function
Mesothelin is a 40 kDa protein that is expressed in mesothelial cells. The protein was first identified by its reactivity with monoclonal antibody K1. Subsequent cloning studies showed that the mesothelin gene encodes a precursor protein that is processed to yield mesothelin which is attached to the cell membrane by a glycophosphatidylinositol linkage and a 31-kDa shed fragment named megakaryocyte-potentiating factor (MPF). Although it has been proposed that mesothelin may be involved in cell adhesion, its biological function is not known. A knockout mouse line that lacks mesothelin reproduces and develops normally.
Mesothelin is over expressed in several human tumors, including mesothelioma, ovarian cancer, pancreatic adenocarcinoma, lung adenocarcinoma, and cholangiocarcinoma. Mesothelin binds MUC16 (also known as CA125), indicating that the interaction of mesothelin and MUC16 may contribute to the implantation and peritoneal spread of tumors by cell adhesion. The region (residues 296-359) consisting of 64 amino acids at the N-terminus of cell surface mesothelin has been identified as the functional binding domain (named IAB) for MUC16/CA125, suggesting the mechanism of mesothelin acting as a MUC16/CA125 functional partner in cancer development.
Medical applications
Mesothelin is a tumor differentiation antigen that is normally present on the mesothelial cells lining the pleura, peritoneum and pericardium. Since mesothelin is overexpressed in several cancers and is immunogenic, the protein could be exploited as tumor marker or as the antigenic target of a therapeutic cancer vaccine. A 2016 review indicates that some immunotherapeutic strategies have shown encouraging results in early-phase clinical trials.
Elevations of serum mesothelin specific to ovarian and other cancer patients may be measured using ELISA assays. Soluble mesothelin is identified as the e |
https://en.wikipedia.org/wiki/Feature%20recognition | The term "feature" implies different meanings in different engineering disciplines. This has resulted in many ambiguous definitions for feature. A feature, in computer-aided design (CAD), usually refers to a region of a part with some interesting geometric or topological properties. These are more precisely called form features. Form features contain both shape information and parametric information of a region of interest. They are now ubiquitous in most current CAD software, where they are used as the primary means of creating 3D geometric models. Examples of form features are extruded boss, loft, etc. Form feature is not the only type of feature that is discussed in CAD literature. Sometimes a part's functional or manufacturing features of the subject of attention. Although it is quite possible to see form features and manufacturing features are called by the same name, they are not exactly the same concepts. For example, one may either use the name "pocket" to refer to a swept cut on the boundary of a part model, or to refer to a trace left on the part boundary by a specific machining operation. The former is exclusively concerned with a geometric shape whereas the latter is concerned with both the geometric shape and a manufacturing operation, needing more parameters in its definition. As such, a manufacturing feature can be minimally defined as a form feature (if it has a form that can uniquely represent it), but not necessarily vice versa (forms can be interpreted differently in different manufacturing domains). Machining features are an important subset of manufacturing features. A machining feature can be regarded as the volume swept by a "cutting" tool, which is always a negative (subtracted) volume. Finally, there is also the concept of assembly feature, which encodes the assembly method between connected components.
Feature data in CAD can be specified either as a collection of surfaces or as volumes. Surface features can be used to describe manufacturi |
https://en.wikipedia.org/wiki/National%20Institute%20of%20Agricultural%20Botany | The National Institute of Agricultural Botany (NIAB) is a plant science research company based in Cambridge, UK.
The NIAB group
The NIAB group consists of:
NIAB
NIAB EMR - a horticultural and agricultural research institute at East Malling, Kent, with a specialism in fruit and clonally propagated crop production. Joined the NIAB Group in 2016.
NIAB CUF - a potato agronomy unit. Joined the NIAB Group in 2013.
NIAB TAG - the arable group that joined in 2009
BCPC - promotes the use of science and technology in the understanding and application of effective, sustainable crop production. Acquired by NIAB in 2018.
History
NIAB was founded in 1919 by Sir Lawrence Weaver. The original Huntingdon Road headquarters building was opened in 1921, by King George V and Queen Mary.
Regional centres
NIAB operates 11 regional centres throughout England:
Cambridge
Morley (Norfolk)
East Malling (Kent)
Sutton Scotney (Hampshire)
Newton Abbot and Plumber Farm (Devon)
Hereford
Telford (Shropshire),
Benniworth and Kirton (Lincolnshire)
Headley Hall (Tadcaster, Yorkshire)
A 12th centre was expected to open at Cirencester (Gloucestershire) in 2020. |
https://en.wikipedia.org/wiki/Pedicel%20%28botany%29 | In botany, a pedicel is a stem that attaches a single flower to the inflorescence. Such inflorescences are described as pedicellate.
Description
Pedicel refers to a structure connecting a single flower to its inflorescence. In the absence of a pedicel, the flowers are described as sessile. Pedicel is also applied to the stem of the infructescence. The word "pedicel" is derived from the Latin pediculus, meaning "little foot". The stem or branch from the main stem of the inflorescence that holds a group of pedicels is called a peduncle. A pedicel may be associated with a bract or bracts.
In cultivation
In Halloween types of pumpkin or squash plants, the shape of the pedicel has received particular attention because plant breeders are trying to optimize the size and shape of the pedicel for the best "lid" for a "jack-o'-lantern".
Gallery
See also
Sessile
Scape |
https://en.wikipedia.org/wiki/International%20Health%20Terminology%20Standards%20Development%20Organisation | The International Health Terminology Standards Development Organisation (IHTSDO), trading as SNOMED International, is an international non-profit organization that owns SNOMED CT, a leading clinical terminology used in electronic health records. IHTSDO was founded in 2007 by 9 charter member countries (Australia, Canada, Denmark, Lithuania, Sweden, the Netherlands, New Zealand, the United Kingdom and the United States) in order to acquire the rights of SNOMED CT from the College of American Pathologists (CAP) and make the development of a global clinical language for healthcare an international, collaborative effort.
Governance
IHTSDO governance is defined in the IHTSDO Articles of Association. The organization is headquartered in the United Kingdom (London).
Since 2007 the number of member countries has increased from 9 to 29. The members were (as of December 2016): Australia, Belgium, Brunei, Canada, Chile, Czech Republic, Denmark, Estonia, Hong Kong, Iceland, India, Ireland, Israel, Lithuania, Malaysia, Malta, Netherlands, New Zealand, Poland, Portugal, Singapore, Slovakia, Slovenia, Spain, Sweden, Switzerland, the United Kingdom, the United States and Uruguay. The member countries provide the bulk of the institutional financing through payment of yearly member fees, which are based on gross national income. Members of IHTSDO can be either an agency of a national government or another body (such as a corporation or regional government agency) which has been endorsed by an appropriate national government authority within the country it represents. Member countries commit themselves to the dissemination of the IHTSDO terminologies within their jurisdiction, including where appropriate the creation of local translations, extensions, and mappings.
The general assembly (GA) is the organization's highest authority and is composed of representatives from all member countries with equal representation (although some member countries have not selected GA representati |
https://en.wikipedia.org/wiki/Decurrent | Decurrent (sometimes decurring) is a term used in botany and mycology to describe plant or fungal parts that extend downward.
In botany, the term is most often applied to leaf blades that partly wrap or have wings around the stem or petiole and extend down along the stem. A "decurrent branching habit" is a plant form common for shrubs and most angiosperm trees, contrasted with the excurrent or "cone-shaped crown" common among many gymnosperms. The decurrent habit is characterized by having weak apical dominance that eventually produces a rounded or spreading tree crown. Examples of trees with decurrent habit are most hardwood trees: oak, hickory, maple, etc.
In mycology, the term is most often applied to the hymenophore of a basidiocarp (such as the lamellae or "gills" of a mushroom or the "pores" of a bracket fungus) when it is broadly attached to and extends down the stipe. |
https://en.wikipedia.org/wiki/Oenanthotoxin | Oenanthotoxin is a toxin extracted from hemlock water-dropwort (Oenanthe crocata) and other plants of the genus Oenanthe. It is a central nervous system poison, and acts as a noncompetitive antagonist of the neurotransmitter gamma-aminobutyric acid. A case has been made for the presence of this toxin in local Oenanthe species playing a causative role in euthanasia in ancient Sardinia. It was crystallized in 1949 by Clarke and co-workers. It is structurally closely related to the toxins cicutoxin and carotatoxin. Oenanthotoxin is a C17 polyacetylene isomer of cicutoxin.
Occurrence
Oenanthotoxin concentration in plants is dependent on seasonal changes and geographical location, the most is present during late winter and early spring. Contrary to most poisonous plants that contain bitter tastes or burning sensations, the water dropwort has a rather sweet and pleasant taste and odor. Water dropwort is characterized by a yellow liquid that changes color due to air exposure. The roots are the most toxic part, although the entire plant contains poisonous properties.
History and culture
The discovery and use of plants containing oenanthotoxin predates Socrates and Homer and its first use as a poison is thought to have been implemented between 1800 BC and 800 BC in Pre-Roman Sardinia. In Ancient Sardinia, it was considered to be a humane form of euthanasia. Elderly people who were unable to care for themselves were given water dropwort and dropped from a high rock to ensure death. It is also believed that Socrates ingested the plant when executed.
A common symptom of oenanthotoxin is risus sardonicus, better known as the Sardonic Grin, coined by Homer in the 8th century BC, due to the victim's rigid smile after ingestion.
Furthermore, as a muscle relaxant, it is believed to have cosmetic botox-like properties in small amounts.
Mechanism of action
Although oenanthotoxin is a relatively well known poison, its mechanism of action is not entirely understood. However, ther |
https://en.wikipedia.org/wiki/Genome%20survey%20sequence | In the fields of bioinformatics and computational biology, Genome survey sequences (GSS) are nucleotide sequences similar to expressed sequence tags (ESTs) that the only difference is that most of them are genomic in origin, rather than mRNA.
Genome survey sequences are typically generated and submitted to NCBI by labs performing genome sequencing and are used, amongst other things, as a framework for the mapping and sequencing of genome size pieces included in the standard GenBank divisions.
Contributions
Genome survey sequencing is a new way to map the genome sequences since it is not dependent on mRNA. Current genome sequencing approaches are mostly high-throughput shotgun methods, and GSS is often used on the first step of sequencing. GSSs can provide an initial global view of a genome, which includes both coding and non-coding DNA and contain repetitive section of the genome unlike ESTs. For the estimation of repetitive sequences, GSS plays an important role in the early assessment of a sequencing project since these data can affect the assessment of sequences coverage, library quality and the construction process. For example, in the estimation of dog genome, it can estimate the global parameters, such as neutral mutation rate and repeat content.
GSS is also an effective way to large-scale and rapidly characterizing genomes of related species where there is only little gene sequences or maps. GSS with low coverage can generate abundant information of gene content and putative regulatory elements of comparative species. It can compare these genes of related species to find out relatively expanded or contracted families. And combined with physical clone coverage, researchers can navigate the genome easily and characterize the specific genomic section by more extensive sequencing.
Limitation
The limitation of genomic survey sequence is that it lacks long-range continuity because of its fragmentary nature, which makes it harder to forecast gene and marker orde |
https://en.wikipedia.org/wiki/Dennis%20Fairclough | Dennis Fairclough is Deputy Chair/Professor at the Computing & Networking Sciences Department at Utah Valley University. He specializes in teaching Borland C++ Builder and Java.
Raised in Northern California, Fairclough earned a Ph.D. at Brigham Young University. He taught at BYU's department of electric engineering from 1976 to 1984. He was an architect of Wicat Systems and began the computer-related section at Eyring Research Institute. He subsequently founded Praxis Computer Systems and Icon Systems. |
https://en.wikipedia.org/wiki/Ef%C3%ADgie%20da%20Rep%C3%BAblica | The (Portuguese for Effigy of the Republic) is used as a national personification, both in Brazil and in Portugal, symbolizing the Republic.
Brazil
The effigy is a representation of a young woman wearing a crown of bay leaves in Roman style and a phrygian cap. It is present in allegoric paintings and sculptures displayed in government buildings throughout Brazil, and engraved on Brazilian real coins and banknotes. It was first used as a pro-Republican icon in the 19th century, inspired by France's Marianne. After the proclamation of the Republic in 1889, it became an important symbol of the newly formed Republic.
Portugal
The Portuguese is represented as a young woman wearing the phrygian cap, probably modeled after Marianne, the French personification of Liberty, familiar from Eugène Delacroix' Liberty Leading the People (1830). As a national distinction, the Portuguese Republic is represented wearing green and red clothes.
The was adopted as a Portuguese State official symbol after the 5 October 1910 revolution, when the Republic substituted the Monarchy in Portugal. Before that, it was used as a political symbol by the Portuguese republicans. Later, the sculpture of Simões de Almeida, representing the Busto da República (Bust of the Republic), became the standard for official use. A reproduction of the Bust of the Republic had to be present, in prominence, in all public buildings and was also present, as an effigy, in the escudo coins. It was considered by the new republican regime as a national symbol of Portugal, like the national coat of arms or the national flag.
Although the original intention was for the to become considered as the personification of the own Portuguese Nation, it never gained popularity in that role. Usually it remains seen only as the personification of the republican regimen, and not as a national symbol. While frequently used in the first half of the 20th century, its use today is rare.
Gallery
See also
National personificatio |
https://en.wikipedia.org/wiki/Ikanos%20Communications | Ikanos Communications, Incorporated, was a provider of semiconductor and software products for use in homes. It was headquartered in Fremont, California. The company’s digital subscriber line, communications processors and other products were used in customer premises equipment from network equipment manufacturers and telecommunications service providers.
History
On December 10, 2001, the founder and chief technology officer of Ikanos, Behrooz Rezvani, announced he was editor of the Institute of Electrical and Electronics Engineers (IEEE) draft standard for Ethernet in the first mile over copper.
On August 24, 2009 Ikanos acquired Conexant's Broadband Access product line for about $54 million in cash. It also announced an investment of $42 million from Tallwood Venture Capital.
In June 2010, John Quigley replaced Michael Gulett as chief executive (who left in April). He was the fifth CEO in six years.
A U.S. appeals court on May 25, 2012 revived a shareholder lawsuit accusing Ikanos of failing to properly disclose known defects in its semiconductor chips at the time it was conducting a 2006 stock offering.
In August 2015, Ikanos was acquired by Qualcomm Atheros in a deal worth around $47 million, with Qualcomm taking on $20 million of liabilities from Ikanos.
In August 2016 Qualcomm Atheros has closed its recently acquired Ikanos operations. |
https://en.wikipedia.org/wiki/Protein%20adulteration%20in%20China | In China, the adulteration and contamination of several food and feed ingredients with inexpensive melamine and other compounds, such as cyanuric acid, ammeline and ammelide, are common practice. These adulterants can be used to inflate the apparent protein content of products, so that inexpensive ingredients can pass for more expensive, concentrated proteins. Melamine by itself has not been thought to be very toxic to animals or humans except possibly in very high concentrations, but the combination of melamine and cyanuric acid has been implicated in kidney failure. Reports that cyanuric acid may be an independently and potentially widely used adulterant in China have heightened concerns for both animal and human health.
Chinese protein export contamination was first identified after the wide recall of many brands of cat and dog food starting in March 2007 (the 2007 pet food recalls). The recalls in North America, Europe and South Africa came in response to reports of kidney failure in pets. Several Chinese companies sold products claimed to be wheat gluten, rice protein or corn gluten, but which proved to be wheat flour adulterated with melamine, cyanuric acid, and other contaminants. The Chinese government was slow to respond, denying that vegetable protein was exported from China and refusing to allow foreign food safety investigators to enter the country. Ultimately, the Chinese government acknowledged that contamination had occurred and arrested the managers of two protein manufacturers identified so far and took other measures to improve food safety and product quality.
Reports of widespread adulteration of Chinese animal feed with melamine have raised the issue of melamine contamination in the human food supply both in China and abroad. On 27 April 2007, the U.S. Food and Drug Administration (FDA) subjected all vegetable proteins imported from China, intended for human or animal consumption, to detention without physical examination, including: wheat gl |
https://en.wikipedia.org/wiki/Quantum%20master%20equation | A quantum master equation is a generalization of the idea of a master equation. Rather than just a system of differential equations for a set of probabilities (which only constitutes the diagonal elements of a density matrix), quantum master equations are differential equations for the entire density matrix, including off-diagonal elements. A density matrix with only diagonal elements can be modeled as a classical random process, therefore such an "ordinary" master equation is considered classical. Off-diagonal elements represent quantum coherence which is a physical characteristic that is intrinsically quantum mechanical.
A formally exact quantum master equation is the Nakajima–Zwanzig equation, which is in general as difficult to solve as the full quantum problem.
The Redfield equation and Lindblad equation are examples of approximate Markovian quantum master equations. These equations are very easy to solve, but are not generally accurate.
Some modern approximations based on quantum master equations, which show better agreement with exact numerical calculations in some cases, include the polaron transformed quantum master equation and the VPQME (variational polaron transformed quantum master equation).
Numerically exact approaches to the kinds of problems to which master equations are usually applied include numerical Feynman integrals, quantum Monte Carlo, DMRG and NRG, MCTDH, and HEOM.
See also
Open quantum system
Quantum dynamics
Quantum coherence
Differential equation
Master equation
Lindblad equation
Nakajima–Zwanzig equation
Feynman integral |
https://en.wikipedia.org/wiki/Intellectual%20property%20brokering | An intellectual property broker mediates between the buyer and seller of intellectual property (IP) and may manage the many steps in the process of creating a deal with regard to the purchase, sale, license, or marketing of intellectual property assets. This may include: patents, trademarks, or inventions (prototypes).
Inventors are faced with several alternatives to making their invention a commercial success. They can build their own start up company from scratch using their own resources. In the United States, they can seek government grants; SBIR (Small Business Innovative Research) and (TTR) Technology Transfer Research to fund the early stage development of their technology. They can contract with third parties such as: venture capital or angel investors to finance a startup or they can sell or license their products to an existing and established company. Often inventors are interested in expanding their own intellectual property assets through licensing and acquisitions.
Because there is not a well defined market around the buying and selling of patents or other IP assets, if an inventor or patent owner wants to monetize their asset, an intellectual property broker can help by serving to connect the inventor or patent owner with one or more interested buyers. The broker should have a network of connections in various market segments which can be used to help market the patent being sold. Potential buyers may include industry peers, competitors, entrepreneurs looking to commercialize the technology, but also defensive patent aggregators, and patent licensing companies.
A competent broker should be able to explain to the inventor or patent owner the spectrum of values that may be assessed to a patent depending on the situation or motivation of the buyer in the market. In addition, in bringing buyers and sellers together, an intellectual property broker may provide any or all of the following services:
initial due diligence
technology assessment
m |
https://en.wikipedia.org/wiki/Orphan%20gene | Orphan genes, ORFans, or taxonomically restricted genes (TRGs) are genes that lack a detectable homologue outside of a given species or lineage. Most genes have known homologues. Two genes are homologous when they share an evolutionary history, and the study of groups of homologous genes allows for an understanding of their evolutionary history and divergence. Common mechanisms that have been uncovered as sources for new genes through studies of homologues include gene duplication, exon shuffling, gene fusion and fission, etc. Studying the origins of a gene becomes more difficult when there is no evident homologue. The discovery that about 10% or more of the genes of the average microbial species is constituted by orphan genes raises questions about the evolutionary origins of different species as well as how to study and uncover the evolutionary origins of orphan genes.
In some cases, a gene can be classified as an orphan gene due to undersampling of the existing genome space. While it is possible that homologues exist for a given gene, that gene will still be classified as an orphan if the organisms harbouring homologues have not yet been discovered and had their genomes sequenced and properly annotated. For example, one study of orphan genes across 119 archaeal and bacterial genomes could identify that at least 56% were recently acquired from integrative elements (or mobile genetic elements) from non-cellular sources such as viruses and plasmids that remain to be explored and characterized, and another 7% arise through horizontal gene transfer from distant cellular sources (with an unknown proportion of the remaining 37% potentially coming from still unknown families of integrative elements). In other cases, limitations in computational methods for detecting homologues may result in missed homologous sequences and thus classification of a gene as an orphan. Homology detection failure appears to account for the majority, but not all orphan genes. In other cases, |
https://en.wikipedia.org/wiki/DAFNE | DAFNE or DAΦNE (Double Annular Φ Factory for Nice Experiments), is an electron-positron collider at the INFN Frascati National Laboratory in Frascati, Italy. It consists of 2 accelerator rings, both approximately 100 meters in length. Since 1999 it has been colliding electrons and positrons at a center of mass energy of 1.02 GeV to create phi mesons (φ). 85% of these decay into kaons (K), whose physics is the subject of most of the experiments at DAFNE.
There have been five experiments at DAFNE:
KLOE (K LOng Experiment), which has been studying CP violation in kaon decays and rare kaon decays since 2000. This is the largest of DAFNE experiments. It has been continued by the KLOE-2 experiment.
FINUDA (FIsica NUcleare a DAFNE), studies the spectra and nonmesonic decays of hypernuclei containing Lambda baryons (Λ). The hypernuclei are produced by negatively charged kaons () striking a thin target.
DEAR (DAFNE Exotic Atoms Research experiment), determines scattering lengths in atoms made from a kaon and a proton or deuteron.
DAFNE Light Laboratory (DAΦNE-L) consists of 3 lines of synchrotron radiation emitted by DAFNE, a fourth is under construction.
SIDDHARTA (SIlicon Drift Detectors for Hadronic Atom Research by Timing Application), aims to improve the precision measurements of X-ray transitions in kaon atoms studied at DEAR.
External links
Homepage of the accelerator division of Frascati National Laboratory: public (Italian), technical
Particle physics facilities
Particle experiments
Research institutes in Italy
Particle accelerators |
https://en.wikipedia.org/wiki/Pepscan | Pepscan is a procedure for mapping and characterizing epitopes involving the synthesis of overlapping peptides and analysis of the peptides in enzyme-linked immunosorbent assays (ELISAs). The method is based on combinatorial chemistry and was pioneered by Mario Geysen and coworkers.
Rob Meloen was one of Geysen's co-workers. He also played an important role in the development of numerous other new technologies, including vaccine and diagnostic product development for several viral diseases. From 1994 to 2010, Meloen was Professor of Special Appointment (Chair: Biomolecular Recognition) at Utrecht University. He was one of the co-founders of the company Pepscan (Lelystad, the Netherlands) and became Scientific Director (CSO). Pepscan is now part of the Biosynth Group.
Twenty-five years later, the Pepscan methodology, evolved and modernized with the latest insights, is still an important part of Pepscan’s epitope mapping platform, which is instrumental in therapeutic antibody development. |
https://en.wikipedia.org/wiki/Suits%20index | The Suits index of a public policy is a measure of tax progressiveness, named for economist Daniel B. Suits. Similar to the Gini coefficient, the Suits index is calculated by comparing the area under the Lorenz curve to the area under a proportional line. For a progressive tax (for example, where higher income tax units pay a greater fraction of their income as tax), the Suits index is positive. A proportional tax (for example, where each unit pays an equal fraction of income) has a Suits index of zero, and a regressive tax (for example, where lower income tax units pay a greater fraction of income in tax) has a negative Suits index. A theoretical tax where the richest person pays all the tax has a Suits index of 1, and a tax where the poorest person pays everything has a Suits index of −1. Tax preferences (credits and deductions) also have a Suits index.
Types of tax
Income tax
By definition, a flat income tax has a Suits index of zero. However, almost all income tax systems allow for some amount of income to be earned without tax (an exemption amount) to avoid collecting tax from very low income units. Also, most income tax systems provide for higher marginal tax rates at higher income. These effects combine to make income taxes generally progressive, and therefore have a positive Suits index.
Sales tax
Sales taxes are generally charged on each purchase, with no low income exemption. Additionally, lower income tax units generally spend a greater proportion of income on taxable purchases, while higher income units will save or invest a larger part of income. Therefore, sales taxes are generally regressive, and have a negative Suits index.
Excise taxes
Excise taxes are typically charged on items like gasoline, alcohol or tobacco products. Since the tax rate is typically high, and there is a practical limit to the amount of product that can be consumed, this tax is generally more regressive and has a very negative Suits index.
Properties
The Suits |
https://en.wikipedia.org/wiki/LZRW | Lempel–Ziv Ross Williams (LZRW) refers to variants of the LZ77 lossless data compression algorithms with an emphasis on improving compression speed through the use of hash tables and other techniques. This family was explored by Ross Williams, who published a series of algorithms beginning with LZRW1 in 1991.
The variants are:
LZRW1
LZRW1-A
LZRW2
LZRW3
LZRW3-A
LZRW4
LZRW5
The LZJB algorithm used in ZFS is derived from LZRW1.
Notes
Lossless compression algorithms
Free data compression software |
https://en.wikipedia.org/wiki/Phonetic%20search%20technology | Phonetic Search Technology (PST) is a method of speech recognition. An audio signal of speech is broken down into series of phonemes, which can be used to identify words.
A string of six phonemes for example, “_B _IY _T _UW _B _IY,” represent the acronym “B2B”. |
https://en.wikipedia.org/wiki/Hyperpyramid | A hyperpyramid is a generalisation of the normal pyramid to n dimensions.
In the case of the pyramid one connects all vertices of the base, a polygon in a plane, to a point outside the plane, which is the peak. The pyramid's height is the distance of the peak from the plane. This construction gets generalised to n dimensions. The base becomes a (n − 1)-polytope in a (n − 1)-dimensional hyperplane. A point called apex is located outside the hyperplane and gets connected to all the vertices of the polytope and the distance of the apex from the hyperplane is called height. This construct is called a n-dimensional hyperpyramid.
A normal triangle is a 2-dimensional hyperpyramid, the triangular pyramid is a 3-dimensional hyperpyramid and the pentachoron or tetrahedral pyramid is a 4-dimensional hyperpyramid with a tetrahedron as base.
The n-dimensional volume of a n-dimensional hyperpyramid can be computed as follows:
Here denotes the n-dimensional volume of the hyperpyramid, A the (n − 1)-dimensional volume of the base and h the height, that is the distance between the apex and the (n − 1)-dimensional hyperplane containing the base A. For n = 2, 3 the formula above yields the standard formulas for the area of a triangle and the volume of a pyramid. |
https://en.wikipedia.org/wiki/Statistical%20model%20specification | In statistics, model specification is part of the process of building a statistical model: specification consists of selecting an appropriate functional form for the model and choosing which variables to include. For example, given personal income together with years of schooling and on-the-job experience , we might specify a functional relationship as follows:
where is the unexplained error term that is supposed to comprise independent and identically distributed Gaussian variables.
The statistician Sir David Cox has said, "How [the] translation from subject-matter problem to statistical model is done is often the most critical part of an analysis".
Specification error and bias
Specification error occurs when the functional form or the choice of independent variables poorly represent relevant aspects of the true data-generating process. In particular, bias (the expected value of the difference of an estimated parameter and the true underlying value) occurs if an independent variable is correlated with the errors inherent in the underlying process. There are several different possible causes of specification error; some are listed below.
An inappropriate functional form could be employed.
A variable omitted from the model may have a relationship with both the dependent variable and one or more of the independent variables (causing omitted-variable bias).
An irrelevant variable may be included in the model (although this does not create bias, it involves overfitting and so can lead to poor predictive performance).
The dependent variable may be part of a system of simultaneous equations (giving simultaneity bias).
Additionally, measurement errors may affect the independent variables: while this is not a specification error, it can create statistical bias.
Note that all models will have some specification error. Indeed, in statistics there is a common aphorism that "all models are wrong". In the words of Burnham & Anderson, "Modeling is an art as well as a |
https://en.wikipedia.org/wiki/David%20Epel | David Epel is a researcher at Hopkins Marine Station in Pacific Grove, California, and a Professor (Emeritus) in the Department of Biology at Stanford University.
Epel earned his Ph.D. at University of California Berkeley under Daniel Mazia. He arrived at Hopkins Marine Station in 1965. Subsequently, Professor Epel spent seven years at University of California San Diego's Scripps Institution of Oceanography. He completed a postdoc with Britton Chance at the University of Pennsylvania.
Professor Epel has been a Guggenheim Fellow, and is a Fellow of the American Association for the Advancement of Science.
Research Focus
His work focuses on egg activation during fertilization, as well as stress on embryonic development.
Scientific Lineage
External links
Epel's Lab
University of California, Berkeley alumni
Stanford University Department of Biology faculty
Fellows of the American Academy of Arts and Sciences
Living people
Fellows of Clare Hall, Cambridge
People from Pacific Grove, California
Year of birth missing (living people) |
https://en.wikipedia.org/wiki/The%20Behavior%20of%20Organisms | The Behavior of Organisms is B.F. Skinner's first book and was published in May 1938 as a volume of the Century Psychology Series. It set out the parameters for the discipline that would come to be called the experimental analysis of behavior (EAB) and Behavior Analysis. This book was reviewed in 1939 by Ernest R. Hilgard. Skinner looks at science behavior and how the analysis of behavior produces data which can be studied, rather than acquiring data through a conceptual or neural process. In the book, behavior is classified either as respondent or operant behavior, where respondent behavior is caused by an observable stimulus and operant behavior is where there is no observable stimulus for a behavior. The behavior is studied in depth with rats and the feeding responses they exhibit. |
https://en.wikipedia.org/wiki/Pitteway%20triangulation | In computational geometry, a Pitteway triangulation is a point set triangulation in which the nearest neighbor of any point p within the triangulation is one of the vertices of the triangle containing p.
Alternatively, it is a Delaunay triangulation in which each internal edge crosses its dual Voronoi diagram edge. Pitteway triangulations are named after Michael Pitteway, who studied them in 1973. Not every point set supports a Pitteway triangulation. When such a triangulation exists it is a special case of the Delaunay triangulation, and consists of the union of the Gabriel graph and convex hull.
History
The concept of a Pitteway triangulation was introduced by . See also , who writes "An optimal partition
is one in which, for any point within any triangle, that point lies at least
as close to one of the vertices of that triangle as to any other data point." The name "Pitteway triangulation" was given by .
Counterexamples
points out that not every point set supports a Pitteway triangulation. For instance, any triangulation of a regular pentagon includes a central isosceles triangle such that a point p near the midpoint of one of the triangle sides has its nearest neighbor outside the triangle.
Relation to other geometric graphs
When a Pitteway triangulation exists, the midpoint of each edge interior to the triangulation must have the two edge endpoints as its nearest neighbors, for any other neighbor would violate the Pitteway property for nearby points in one of the two adjacent triangles. Thus, a circle having that edge as diameter must be empty of vertices, so the Pitteway triangulation consists of the Gabriel graph together with the convex hull of the point set. Conversely, when the Gabriel graph and convex hull together form a triangulation, it is a Pitteway triangulation.
Since all Gabriel graph and convex hull edges are part of the Delaunay triangulation, a Pitteway triangulation, when it exists, is unique for points in general position and coincides |
https://en.wikipedia.org/wiki/Atomic%20form%20factor | In physics, the atomic form factor, or atomic scattering factor, is a measure of the scattering amplitude of a wave by an isolated atom. The atomic form factor depends on the type of scattering, which in turn depends on the nature of the incident radiation, typically X-ray, electron or neutron. The common feature of all form factors is that they involve a Fourier transform of a spatial density distribution of the scattering object from real space to momentum space (also known as reciprocal space). For an object with spatial density distribution, , the form factor, , is defined as
,
where is the spatial density of the scatterer about its center of mass (), and is the momentum transfer. As a result of the nature of the Fourier transform, the broader the distribution of the scatterer in real space , the narrower the distribution of in ; i.e., the faster the decay of the form factor.
For crystals, atomic form factors are used to calculate the structure factor for a given Bragg peak of a crystal.
X-ray form factors
X-rays are scattered by the electron cloud of the atom and hence the scattering amplitude of X-rays increases with the atomic number, , of the atoms in a sample. As a result, X-rays are not very sensitive to light atoms, such as hydrogen and helium, and there is very little contrast between elements adjacent to each other in the periodic table. For X-ray scattering, in the above equation is the electron charge density about the nucleus, and the form factor the Fourier transform of this quantity. The assumption of a spherical distribution is usually good enough for X-ray crystallography.
In general the X-ray form factor is complex but the imaginary components only become large near an absorption edge. Anomalous X-ray scattering makes use of the variation of the form factor close to an absorption edge to vary the scattering power of specific atoms in the sample by changing the energy of the incident x-rays hence enabling the extraction of more deta |
https://en.wikipedia.org/wiki/Truffle%20oil | Truffle oil is a modern culinary ingredient used to impart the flavor and aroma of truffles to a dish. The ingredient is commonly used as a finishing oil in a variety of dishes, including truffle fries, pasta dishes, pizzas, and puréed foods such as mashed potatoes and deviled eggs. Truffle oil is available in all seasons and is significantly less expensive than fresh truffles. This has also led to a market growth in the product and an increase in the availability of truffle-flavored foods.
Truffle oil is controversial as a flavoring ingredient, as nearly all truffle oil is produced from one synthetic flavor compound, and may lack the complex flavors and aromas of fresh truffles.
Composition
Truffle oil can be produced using any oil. Common versions use olive oil, or a more neutral flavorless oil such as canola or grapeseed oil.
Some truffle oils are made with the residue of truffles collected or prepared for sale. Many truffle oils are not made from truffles, but instead use manufactured aromatic compounds including 2,4-dithiapentane (one of many aroma active compounds that can be found in some truffle varietals) with an oil base. There are no regulations regarding the labeling of 2,4-dithiapentane and it can legally be called truffle aroma, truffle flavor, truffle concentrate or other similar terms, even though it is not extracted from truffles. In the United States, the ingredient may use the modifiers "organic" or "natural" as long as the components meet the federal requirements for those terms.
The appearance of truffle oils is determined by the base oil, ranging from clear to cloudy and yellow to green. Some include a piece of truffle in the bottle. These pieces can be from any of over 200 different truffle species and may be listed as "black truffle" or "white truffle" even if not prized culinary varietals such as the black Périgord or white Alba truffle.
History
Preserved truffles have a long history of use, as fresh truffles are seasonal, and require |
https://en.wikipedia.org/wiki/Stub%20%28distributed%20computing%29 | In distributed computing, a stub is a program that acts as a temporary replacement for a remote service or object. It allows the client application to access a service as if it were local, while hiding the details of the underlying network communication. This can simplify the development process, as the client application does not need to be aware of the complexities of distributed computing. Instead, it can rely on the stub to handle the remote communication, while providing a familiar interface for the developer to work with.
Application
The stub represents a remote object or service on a local system. It acts as a proxy for the remote service and allows the client program to make method calls on the remote object as if it were local. The process of generating stubs involves creating a client-side proxy object that provides the same interface as the remote service, but routes method calls to the actual remote object.
In distributed computing, a stub is a piece of code that converts parameters passed between the client and server during a remote procedure call (RPC). The main purpose of an RPC is to allow a local computer (client) to invoke procedures on a remote computer (server). Since the client and server have different address spaces, the parameters used in a function call must be converted. Otherwise, the parameter values would be unusable because pointers to parameters in one computer's memory would reference different data on the other computer. Also, the client and server can have different data representations, even for simple parameters like integers (e.g., big-endian versus little-endian). Stubs handle parameter conversion, making a remote procedure call look like a local function call to the remote computer.
Stub libraries are crucial in distributed computing, as they allow for local procedure calls to be made to remote objects or services. The client-side stub or proxy is responsible for converting the parameters used in a function call and deconv |
https://en.wikipedia.org/wiki/XLIFF | XLIFF (XML Localization Interchange File Format) is an XML-based bitext format created to standardize the way localizable data are passed between and among tools during a localization process and a common format for CAT tool exchange. The XLIFF Technical Committee (TC) first convened at OASIS in December 2001 (first meeting in January 2002), but the first fully ratified version of XLIFF appeared as XLIFF Version 1.2 in February 2008. Its current specification is v2.1 released on 2018-02-13, which is backwards compatible with v2.0 released on 2014-08-05.
The specification is aimed at the localization industry. It specifies elements and attributes to store content extracted from various original file formats and its corresponding translation. The goal was to abstract the localization skills from the engineering skills related to specific formats such as HTML.
XLIFF is part of the Open Architecture for XML Authoring and Localization (OAXAL) reference architecture.
XLIFF 2.0 and higher (the current OASIS ratified format)
The XLIFF Technical Committee is currently preparing to start working on XLIFF Version 2.2.
Prior to making of the major new version 2.0, feedback was gathered from XLIFF's user community which was integrated into the following generation version of the standard. Two of the primary methods used included compiling a list of extensions used by XLIFF toolmakers, and compiling a list of XLIFF features supported by each XLIFF tool.
Makers of XLIFF tools have taken advantage of XLIFF's extensibility mechanism in order to implement a number of features. By collecting a list of these extension points and analyzing them for common tasks, the XLIFF TC hopes to improve the XLIFF 2.0 Specification to include mechanisms that will enable the toolmakers to support these features without using extensibility.
Makers of XLIFF tools have supported different sets of features in the XLIFF 1.2 Specification. By compiling a list of these features, the XLIFF TC hopes t |
https://en.wikipedia.org/wiki/William%20Allan%20Award | The William Allan Award, given by the American Society of Human Genetics, was established in 1961 in memory of William Allan (1881–1943), one of the first American physicians to conduct extensive research in human genetics.
The William Allan Award is presented annually to recognize substantial and far-reaching scientific contributions to human genetics carried out over a sustained period of scientific inquiry and productivity. An award of $25,000 and an engraved medal are presented at the Annual Meeting.
Award recipients
Source: ASHG
See also
List of genetics awards
List of medicine awards |
https://en.wikipedia.org/wiki/Page%20%28computer%20memory%29 | A page, memory page, or virtual page is a fixed-length contiguous block of virtual memory, described by a single entry in the page table. It is the smallest unit of data for memory management in a virtual memory operating system. Similarly, a page frame is the smallest fixed-length contiguous block of physical memory into which memory pages are mapped by the operating system.
A transfer of pages between main memory and an auxiliary store, such as a hard disk drive, is referred to as paging or swapping.
Explanation
Computer memory is divided into pages so that information can be found more quickly.
The concept is named by analogy to the pages of a printed book. If a reader wanted to find, for example, the 5,000th word in the book, they could count from the first word. This would be time-consuming. It would be much faster if the reader had a listing of how many words are on each page. From this listing they could determine which page the 5,000th word appears on, and how many words to count on that page. This listing of the words per page of the book is analogous to a page table of a computer file system.
Page size
Page size trade-off
Page size is usually determined by the processor architecture. Traditionally, pages in a system had uniform size, such as 4,096 bytes. However, processor designs often allow two or more, sometimes simultaneous, page sizes due to its benefits. There are several points that can factor into choosing the best page size.
Page table size
A system with a smaller page size uses more pages, requiring a page table that occupies more space. For example, if a 232 virtual address space is mapped to 4 KiB (212 bytes) pages, the number of virtual pages is 220 = (232 / 212). However, if the page size is increased to 32 KiB (215 bytes), only 217 pages are required. A multi-level paging algorithm can decrease the memory cost of allocating a large page table for each process by further dividing the page table up into smaller tables, effectively pa |
https://en.wikipedia.org/wiki/The%20Western%20Australian%20Flora%3A%20A%20Descriptive%20Catalogue | The Western Australian Flora: A Descriptive Catalogue was published by the Wildflower Society of Western Australia, the Western Australian Herbarium,
CALM, and the Botanic Gardens and Parks Authority of Perth, Western Australia.
Publication
At the time of publication in 2000 the number of published vascular plant species recognised had reached 9640 - almost double since the work of Beard in 1969.
The publication of the book was an important stage of the cataloguing of details of flora in Western Australia.
The introduction of the book by Alex R. Chapman is available as a PDF file, at the external link at FloraBase.
Floristic regions
The front inside cover has an important distinctive map of Western Australian Biogeographic Regions and Botanical Provinces, after Creswell and Thackray 1995 - the authors of the IBRA system.
After Beard's summary of Diels, Burbidge and Gardner in 1980 he established the three phytogeographic provinces - Northern, Eremaean, and South West, and the map links in the relationship of these with the IBRA regions and sub regions.
Publication details
Paczkowska, Grazyna and Alex R. Chapman (2000). The Western Australian Flora : a descriptive catalogue Perth, W.A: Wildflower Society of Western Australia : Western Australian Herbarium: Western Australian Botanic Gardens & Parks Authority (pbk.)
See also
How to Know Western Australian Wildflowers
Vegetation Survey of Western Australia |
https://en.wikipedia.org/wiki/Storage%20record | In computer science, a storage record is:
A group of related data, words, or fields treated as a meaningful unit; for instance, a Name, Address, and Telephone Number can be a "Personal Record".
A self-contained collection of information about a single object; a record is made up of a number of distinct items, called fields.
In IBM mainframes, a record is a basic unit of device-to-program data transfers. Mainframe files, properly called data sets, are traditionally structured collections of records, as opposed to modern byte stream access files. Records may have a fixed length or variable length.
In Unix-like systems, a number of programs (for example, awk, join, and sort) are designed to process data consisting of records (called lines) each separated by newlines, where each record may contain a number of fields separated by spaces, commas, or some other character.
See also
Block (data storage)
Object composition
Record (computer science)
Row (database)
User-defined type
Computer data storage |
https://en.wikipedia.org/wiki/Vaginal%20flora | Vaginal flora, vaginal microbiota or vaginal microbiome are the microorganisms that colonize the vagina. They were discovered by the German gynecologist Albert Döderlein in 1892 and are part of the overall human flora.
The amount and type of bacteria present have significant implications for an individual's overall health. The primary colonizing bacteria of a healthy individual are of the genus Lactobacillus, such as L. crispatus, and the lactic acid they produce is thought to protect against infection by pathogenic species.
Lactobacilli
The primary colonizing bacteria of a healthy individual are of the genus Lactobacillus (90–95%), the most common being L. crispatus, L. iners, L. jensenii, and L. gasseri. Since the first description of lactobacilli by Döderlein, lactobacilli have been generally considered the gatekeepers of the vaginal ecosystem. Lactobacilli have been shown to inhibit in vitro growth of pathogenic microorganisms, e.g. Bacteroides fragilis, Escherichia coli, Gardnerella vaginalis, Mobiluncus spp., Neisseria gonorrhoeae, Peptostreptococcus anaerobius, Prevotella bivia and Staphylococcus aureus. It is generally accepted that this is achieved mainly through the action of lactic acid. Moreover, lactobacilli normally help to prevent long-term colonization of the vagina by adhering to vaginal epithelial cells. This usually reduces pathogens from infecting to the vaginal epithelium.
Next to lactic acid production and competition for adherence, other antagonistic mechanisms include hydrogen peroxide (a broad-spectrum antimicrobial) and bacteriocins (target-specific antimicrobials) production.
pH and lactic acid
Low pH is generally accepted to be the main mechanism controlling the composition of the vaginal microflora. Although the lactic acid produced by lactobacilli contributes to the vaginal acidity, it is still not proven to be the primary source of low vaginal pH, but the fact remains that most lactobacilli thrive best at a pH < 3.5 .
Normal va |
https://en.wikipedia.org/wiki/Track%20%28disk%20drive%29 | A disk drive track is a circular path on the surface of a disk or diskette on which information is magnetically recorded and from which recorded information is read.
A track is a physical division of data in a disk drive, as used in the Cylinder-Head-Record (CCHHR) addressing mode of a CKD disk. The concept is concentric, through the physical platters, being a data circle per each cylinder of the whole disk drive. In other words, the number of tracks on a single surface in the drive exactly equals the number of cylinders of the drive.
Tracks are subdivided into blocks (or sectors, pages) (see: Storage block and Virtual page).
The term track is sometimes prefaced with the word logical (i.e. "3390-9 has 3 logical tracks per physical track") to emphasize that it is used as an abstract concept, not a track in the physical sense.
See also
Hard disk drive
Disk sector
Cylinder
Computer storage devices
Rotating disc computer storage media |
https://en.wikipedia.org/wiki/Storage%20effect | The storage effect is a coexistence mechanism proposed in the ecological theory of species coexistence, which tries to explain how such a wide variety of similar species are able to coexist within the same ecological community or guild. The storage effect was originally proposed in the 1980s to explain coexistence in diverse communities of coral reef fish, however it has since been generalized to cover a variety of ecological communities. The theory proposes one way for multiple species to coexist: in a changing environment, no species can be the best under all conditions. Instead, each species must have a unique response to varying environmental conditions, and a way of buffering against the effects of bad years. The storage effect gets its name because each population "stores" the gains in good years or microhabitats (patches) to help it survive population losses in bad years or patches. One strength of this theory is that, unlike most coexistence mechanisms, the storage effect can be measured and quantified, with units of per-capita growth rate (offspring per adult per generation).
The storage effect can be caused by both temporal and spatial variation. The temporal storage effect (often referred to as simply "the storage effect") occurs when species benefit from changes in year-to-year environmental patterns, while the spatial storage effect occurs when species benefit from variation in microhabitats across a landscape.
The concept
For the storage effect to operate, it requires variation (i.e. fluctuations) in the environment and thus can be termed a "fluctuation-dependent mechanism". This variation can come from a large degree of factors, including resource availability, temperature, and predation levels. However, for the storage effect to function, this variation must change the birth, survival, or recruitment rate of species from year to year (or patch to patch).
For competing species within the same community to coexist, they have to meet one fund |
https://en.wikipedia.org/wiki/Glossary%20of%20systems%20theory | A glossary of terms relating to systems theory.
A
Adaptive capacity: An important part of the resilience of systems in the face of a perturbation, helping to minimise loss of function in individual human, and collective social and biological systems.
Allopoiesis: The process whereby a system produces something other than the system itself.
Allostasis: The process of achieving stability, or homeostasis, through physiological or behavioral change.
Autopoiesis: The process by which a system regenerates itself through the self-reproduction of its own elements and of the network of interactions that characterize them. An autopoietic system renews, repairs, and replicates or reproduces itself in a flow of matter and energy. Note: from a strictly Maturanian point of view, autopoiesis is an essential property of biological/living systems.
B
Black box: A technical term for a device or system or object when it is viewed primarily in terms of its input and output characteristics, without observing or describing its internal structure or behaviour.
Boundaries: The parametric conditions, often vague, always subjectively stipulated, that delimit and define a system and set it apart from its environment.
C
Cascading failure: Failure in a system of interconnected parts, where the service provided depends on the operation of a preceding part, and the failure of a preceding part can trigger the failure of successive parts.
Closed system: A system which can exchange energy (as heat or work), but not matter, with its surroundings.
Complexity: A complex system is characterised by components that interact in multiple ways and follow local rules. A complicated system is characterised by its layers.
Culture: The result of individual learning processes that distinguish one social group of higher animals from another. In humans culture is the set of interrelated concepts, products and activities through which humans group themselves, interact with each other, and become aware o |
https://en.wikipedia.org/wiki/Quantum%20graph | In mathematics and physics, a quantum graph is a linear, network-shaped structure of vertices connected on edges (i.e., a graph) in which each edge is given a length and where a differential (or pseudo-differential) equation is posed on each edge. An example would be a power network consisting of power lines (edges) connected at transformer stations (vertices); the differential equations would then describe the voltage along each of the lines, with boundary conditions for each edge provided at the adjacent vertices ensuring that the current added over all edges adds to zero at each vertex.
Quantum graphs were first studied by Linus Pauling as models of free electrons in organic molecules in the 1930s. They also arise in a variety of mathematical contexts, e.g. as model systems in quantum chaos, in the study of waveguides, in photonic crystals and in Anderson localization, or as limit on shrinking thin wires. Quantum graphs have become prominent models in mesoscopic physics used to obtain a theoretical understanding of nanotechnology. Another, more simple notion of quantum graphs was introduced by Freedman et al.
Aside from actually solving the differential equations posed on a quantum graph for purposes of concrete applications, typical questions that arise are those of controllability (what inputs have to be provided to bring the system into a desired state, for example providing sufficient power to all houses on a power network) and identifiability (how and where one has to measure something to obtain a complete picture of the state of the system, for example measuring the pressure of a water pipe network to determine whether or not there is a leaking pipe).
Metric graphs
A metric graph
is a graph consisting of a set of vertices and
a set of edges where each edge has been associated
with an interval so that is the coordinate on the
interval, the vertex corresponds to and
to or vice versa. The choice of which vertex lies at zero is
arbitrary |
https://en.wikipedia.org/wiki/Senile%20osteoporosis | Senile osteoporosis has been recently recognized as a geriatric syndrome with a particular pathophysiology. There are different classification of osteoporosis: primary, in which bone loss is a result of aging and secondary, in which bone loss occurs from various clinical and lifestyle factors. Primary, or involuntary osteoporosis, can further be classified into Type I or Type II. Type I refers to postmenopausal osteoporosis and is caused by the deficiency of estrogen. While senile osteoporosis is categorized as an involuntary, Type II, and primary osteoporosis, which affects both men and women over the age of 70 years. It is accompanied by vitamin D deficiency, body's failure to absorb calcium, and increased parathyroid hormone.
Research over the years has shown that senile osteoporosis is the product of a skeleton in an advanced stage of life and can be caused by a deficiency caused by calcium. However, physicians are also coming to the conclusion that multiple mechanisms in the development stages of the disease interact together resulting in an osteoporotic bone, regardless of age. Still, elderly people make up the fastest growing population in the world. As bone mass declines with age, the risk of fractures increases. Annual incidence of osteoporotic fractures is more than 1.5 million in the US and notably 20% of people die during the first year after a hip fracture.
It costs the US health system around $17 billion annually, with the cost projecting to $50 billion by 2040. These costs represent a higher burden compared to other disease states, such as breast cancer, stroke, diabetes, or chronic lung disease. Although there are cost effective and well-tolerated treatments, 23% of the diagnosed are women over 67 have received either bone mineral density (BMD) tests or prescription for treatment after fracture. The clinical and economic burdens indicate there should be more effort in assessment of risk, prevention, and early intervention when it comes to osteoporo |
https://en.wikipedia.org/wiki/Name%20tag | A name tag is a badge or sticker worn on the outermost clothing as a means of displaying the wearer's name for others to view.
Name tags may be temporary, such as a sticker with the iconic image being the "Hello! My Name Is "; or it may be a more durable type. Temporary ones typically can be written upon so that the wearer's name may be handwritten or printed. Permanent name tags are usually made of lightweight metal or plastic and may be known as name badges.
Name tags may be attached to garments with adhesive or worn with the assistance of a magnet, pin or velcro. Plastic or metal name tags can be attached to various backings used to attach to the clothing of the wearer. There are many types of name tag backings, including magnetic backings, locking pins, swivel clips, military clutch pins, alligator clips, and cell phone attachments. Magnetic backings, because they do not puncture clothing with pins, have recently become more popular for name tags. Some name tags are worn around the neck using a lanyard or necklace.
Name tags with magnetic backings pose a harmful threat to people who have pacemakers, as the magnet will interfere with the implant's normal function. It is suggested that people who have pacemakers use pinback backings with their name tags to avoid any disturbance with the pacemaker.
Name tags are used by some customer service companies, such as fast food restaurants, so that customers may identify employees by name. Professional employees or representatives of public-facing organizations such as universities, banks, or other companies where employees do not wear uniforms, may wear name tags as a way of distinguishing or identifying the bearer as such, while allowing the employee to wear daily business wear.
Military
Military personnel commonly wear name badges on their uniforms, though usually displaying only the family (last) name. However, there is not much emphasis on this formatting simply because of the plethora of cultures and naming c |
https://en.wikipedia.org/wiki/Joseph%20Zubin%20Award | The Joseph Zubin Award may refer to three different psychology awards named in honor of the psychologist Joseph Zubin.
Joseph Zubin Memorial Fund Award
The Joseph Zubin Memorial Fund Award was granted by the Joseph Zubin Memorial Fund at the Research Foundation for Mental Hygiene at the New York State Psychiatric Institute. It was established by Zubin's colleagues and family to "recognize investigators who are in an early stage of their career, but have already made significant contributions to research in any area of psychopathology." The award was co-sponsored by the University of Pittsburgh Medical Center Western Psychiatric Institute and Clinic, the University of Pittsburgh School of Medicine and the VA Pittsburgh Healthcare System. The award included an honorarium and was presented until 2010.
Recipients:
Joseph Zubin Award (SRP)
The Joseph Zubin Award is a lifetime achievement award given by the Society for Research in Psychopathology. It was established in 1986 and officially named the Joseph Zubin Award in 1990.
Recipients:
Source: Society for Research in Psychopathology
Joseph Zubin Award (APPA)
The Joseph Zubin Award was established by the American Psychopathological Association in 1992 and is granted to psychologists who have "made seminal contributions to psychopathology research."
Recipients:
Source: APPA Previous Award Winners
See also
List of psychology awards |
https://en.wikipedia.org/wiki/Qa-1b | Within molecular and cell biology, Qa-1b is a MHC class I molecule and is the functional homolog of HLA-E in humans. Qa-1b is characterised by its limited polymorphisms and small peptide repertoire. Qa-1b binds to peptides derived from signal peptides of MHC class Ia molecule and interact with the CD94/NKG2 receptors on natural killer cells. The Qa-1b-peptide complex signals natural killer cells not to engage in cell lysis. Despite its homology with HLA-E, it seems that Qa-1b evolved a similar function to HLA-E coincidentally. |
https://en.wikipedia.org/wiki/Cleaner%20fish | Cleaner fish are fish that show a specialist feeding strategy by providing a service to other species, referred to as clients, by removing dead skin, ectoparasites, and infected tissue from the surface or gill chambers. This example of cleaning symbiosis represents mutualism and cooperation behaviour, an ecological interaction that benefits both parties involved. However, the cleaner fish may consume mucus or tissue, thus creating a form of parasitism called cheating. The client animals are typically fish of a different species, but can also be aquatic reptiles (sea turtles and marine iguana), mammals (manatees and whales), or octopuses. A wide variety of fish including wrasse, cichlids, catfish, pipefish, lumpsuckers, and gobies display cleaning behaviors across the globe in fresh, brackish, and marine waters but specifically concentrated in the tropics due to high parasite density. Similar behaviour is found in other groups of animals, such as cleaner shrimps.
There are two types of cleaner fish, obligate full time cleaners and facultative part time cleaners where different strategies occur based on resources and local abundance of fish. Cleaning behaviour takes place in pelagic waters as well as designated locations called cleaner stations. Cleaner fish interaction durations and memories of reoccurring clients are influenced by the neuroendocrine system of the fish, involving hormones arginine vasotocin, Isotocin and serotonin.
Conspicuous coloration is a method used by some cleaner fish, where they often display a brilliant blue stripe that spans the length of the body. Other species of fish, called mimics, imitate the behavior and phenotype of cleaner fish to gain access to client fish tissue.
The specialized feeding behaviour of cleaner fish has become a valuable resource in salmon aquaculture in Atlantic Canada, Scotland, Iceland and Norway for prevention of sea lice outbreaks which benefits the economy and environment by minimizing the use of chemical del |
https://en.wikipedia.org/wiki/Prunus%20nigra | Prunus nigra, the Canada plum, Canadian plum, or black plum, is a species of Prunus native to eastern North America.
Description
Prunus nigra is a deciduous shrub or small tree growing to tall with a trunk up to in diameter, with a low-branched, dense crown of stiff, rigid, branches. The bark is gray-brown, older layers coming off in thick plates. The branchlets are bright green at first, later become dark brown tinged with red, and spiny. The winter buds are chestnut brown, long-pointed at the tip, up to long.
The leaves are alternate, simple, and oblong-ovate or obovate, long and broad, wedge-shaped, slightly heart-shaped, or rounded at base, doubly crenaulate-serrate, abruptly contracted to a narrow point at the apex, feather-veined, midrib conspicuous; they emerge from the bud convolute, downy, slightly tinged with red, are smooth, becoming bright green above and paler beneath when full grown. The leaf petioles are stout, bearing two large dark glands and early deciduous, lanceolate, and three to five-lobed stipules.
The flowers are diameter, with five rounded petals, white fading to pale pink, with a more or less irregularly notched margin; they are slightly fragrant, borne in three to four-flowered umbels, with short, thick peduncles, and appear before the leaves in mid to late spring. The flower stalks are slender and dark red. The calyx is conic, dark red, five-lobed, the lobes acute, finally reflexed, glandular, smooth on the inner surface, imbricate in bud, ovate, with short claws, imbricate in bud. There are 15–20 stamens, inserted on the calyx tube; filaments thread-like; anthers purplish, introrse, two-celled; cells opening longitudinally; the pistil has a superior ovary in the bottom of calyx tube, one-celled, with two ovules.
The fruit is an oblong-oval drupe, long with a tough, thick, orange red skin, free from bloom, yellow flesh adherent to the stone; the stone oval, compressed. It matures in late summer or early autumn. The cotyledons a |
https://en.wikipedia.org/wiki/Alloy%20%28specification%20language%29 | In computer science and software engineering, Alloy is a declarative specification language for expressing complex structural constraints and behavior in a software system. Alloy provides a simple structural modeling tool based on first-order logic. Alloy is targeted at the creation of micro-models that can then be automatically checked for correctness. Alloy specifications can be checked using the Alloy Analyzer.
Although Alloy is designed with automatic analysis in mind, Alloy differs from many specification languages designed for model-checking in that it permits the definition of infinite models. The Alloy Analyzer is designed to perform finite scope checks even on infinite models.
The Alloy language and analyzer are developed by a team led by Daniel Jackson at the Massachusetts Institute of Technology in the United States.
History and influences
The first version of the Alloy language appeared in 1997. It was a rather limited object modeling language. Succeeding iterations of the language "added quantifiers, higher arity relations, polymorphism, subtyping, and signatures".
The mathematical underpinnings of the language were heavily influenced by the Z notation, and the syntax of Alloy owes more to languages such as Object Constraint Language.
The Alloy Analyzer
The Alloy Analyzer was specifically developed to support so-called "lightweight formal methods". As such, it is intended to provide fully automated analysis, in contrast to the interactive theorem proving techniques commonly used with specification languages similar to Alloy. Development of the Analyzer was originally inspired by the automated analysis provided by model checkers. However, model-checking is ill-suited to the kind of models that are typically developed in Alloy, and as a result the core of the Analyzer was eventually implemented as a model-finder built atop a boolean SAT solver.
Through version 3.0, the Alloy Analyzer incorporated an integral SAT-based model-finder based on an o |
https://en.wikipedia.org/wiki/Prunus%20americana | Prunus americana, commonly called the American plum, wild plum, or Marshall's large yellow sweet plum, is a species of Prunus native to North America from Saskatchewan and Idaho south to New Mexico and east to Québec, Maine and Florida.
Prunus americana has often been planted outside its native range and sometimes escapes cultivation. It is commonly confused with the Canada plum (Prunus nigra), although the fruit is smaller and rounder and bright red as opposed to yellow. Many cultivated varieties have been derived from this species. It forms an excellent stock upon which to graft the domestic plum.
Description
The American plum grows as a large shrub or small tree, reaching up to . It is adapted to coarse- and medium-textured soils, but not to fine soils (silt or clay). Beneficially, the shrub survives harsh winters, down to temperatures of -40 degrees (Fahrenheit); but has little tolerance for shade, drought, or fire. Its growth is most active in spring and summer; it blooms in spring and starts fruiting in summer. It propagates naturally by seed, expanding as a stand relatively slowly, due to its long time to maturity when grown from seed.
The roots are shallow, widely spread, and send up suckers. The numerous stems per plant become scaly with age. The tree has a crown width and height of 10 feet at maturity. The branches are thorny. The leaves are alternately arranged, with an oval shape. The leaf length is usually long. The upper surface of the leaf is dark green; the underside is smooth and pale. The small white flowers with five petals occur singly or in clusters in the leaf axils. The globular fruits are about in diameter.
Taxonomy
Prunus americana var. lanata Sudw is considered a synonym of Prunus mexicana, and Prunus americana var. nigra is considered a synonym of Prunus nigra.
Chickasaw plum (Prunus angustifolia Marsh.) hybridizes naturally with P. americana to produce P. × orthosepala Koehne.
In cultivation, many crosses have been made between A |
https://en.wikipedia.org/wiki/Microfauna | Microfauna (Ancient Greek mikros "small" + Neo-Latin fauna "animal") refers to microscopic animals and organisms that exhibit animal-like qualities. Microfauna are represented in the animal kingdom (e.g. nematodes, small arthropods) and the protist kingdom (i.e. protozoans).
Habitat
Microfauna are present in every habitat on Earth. They fill essential roles as decomposers and food sources for lower trophic levels, and are necessary to drive processes within larger organisms.
Role
One particular example of the role of microfauna can be seen in soil, where they are important in the cycling of nutrients in ecosystems. Soil microfauna are capable of digesting just about any organic substance, and some inorganic substances. These organisms are often essential links in the food chain between primary producers and larger species. For example, zooplankton are widespread microscopic animals and protists which feed on algae and detritus in the ocean, such as foraminifera.
Microfauna also aid in digestion and other processes in larger organisms.
Cryptozoa
The microfauna are the least understood of soil life, due to their small size and great diversity. Many microfauna are members of the so-called cryptozoa, animals that remain undescribed by science. Out of the estimated 10-20 million animal species in the world, only 1.8 million have been given scientific names, and many of the remaining millions are likely microfauna, much of it from the tropics.
Phyla
Notable phyla include:
Microscopic arthropods, including dust mites, spider mites, and some crustaceans such as copepods and certain cladocera.
Tardigrades ("water bears")
Rotifers, which are filter feeders that are usually found in fresh water.
Some nematode species
Many loricifera, including the recently discovered anaerobic species, which spend their entire lives in an anoxic environment.
See also
Fauna
Megafauna
Mesofauna |
https://en.wikipedia.org/wiki/Microlithography | Microlithography is a general name for any manufacturing process that can create a minutely patterned thin film of protective materials over a substrate, such as a silicon wafer, in order to protect selected areas of it during subsequent etching, deposition, or implantation operations.
The term is normally used for processes that can reliably produce features of microscopic size, such as 10 micrometres or less. The term nanolithography may be used to designate processes that can produce nanoscale features, such as less than 100 nanometres.
Microlithography is a microfabrication process that is extensively used in the semiconductor industry and also manufacture microelectromechanical systems.
Processes
Specific microlithography processes include:
Photolithography using light projected on a photosensitive metarial film (photoresist).
Electron beam lithography, using a steerable electron beam.
Nanoimprinting
Interference lithography
Magnetolithography
Scanning probe lithography
Surface-charge lithography
Diffraction lithography
These processes differ in speed and cost, as well as in the material they can be applied to and the range of feature sizes they can produce. For instance, while the size of features achievable with photolithography is limited by the wavelength of the light used, the technique it is considerably faster and simpler than electron beam lithography, that can achieve much smaller ones.
Applications
The main application for microlithography is fabrication of integrated circuits ("electronic chips"), such as solid-state memories and microprocessors. They can also be used to create diffraction gratings, microscope calibration grids, and other flat structures with microscopic details.
See also
Printed circuit board |
https://en.wikipedia.org/wiki/Implementation%20theory | Implementation theory is an area of research in game theory concerned with whether a class of mechanisms (or institutions) can be designed whose equilibrium outcomes implement a given set of normative goals or welfare criteria.
There are two general types of implementation problems: the economic problem of producing and allocating public and private goods and choosing over a finite set of alternatives. In the case of producing and allocating public/private goods, solution concepts are focused on finding dominant strategies.
In his paper "Counterspeculation, Auctions, and Competitive Sealed Tenders", William Vickrey showed that if preferences are restricted to the case of quasi-linear utility functions then the mechanism dominant strategy is dominant-strategy implementable. "A social choice rule is dominant strategy incentive compatible, or strategy-proof, if the associated revelation mechanism has the property that honestly reporting the truth is always a dominant strategy for each agent." However, the payments to agents become large, sacrificing budget neutrality to incentive compatibility.
In a game where multiple agents are to report their preferences (or their type), it may be in the best interest of some agents to lie about their preferences. This may improve their payoff, but it may not be seen as a fair outcome to other agents.
Although largely theoretical, implementation theory may have profound implications on policy creation because some social choice rules may be impossible to implement under specific game conditions.
See also
Implementability (mechanism design) |
https://en.wikipedia.org/wiki/Lie%20algebra%20bundle | In mathematics, a weak Lie algebra bundle
is a vector bundle over a base space X together with a morphism
which induces a Lie algebra structure on each fibre .
A Lie algebra bundle is a vector bundle in which
each fibre is a Lie algebra and for every x in X, there is an open set containing x, a Lie algebra L and a homeomorphism
such that
is a Lie algebra isomorphism.
Any Lie algebra bundle is a weak Lie algebra bundle, but the converse need not be true in general.
As an example of a weak Lie algebra bundle that is not a strong Lie algebra bundle, consider the total space over the real line . Let [.,.] denote the Lie bracket of and deform it by the real parameter as:
for and .
Lie's third theorem states that every bundle of Lie algebras can locally be integrated to a bundle of Lie groups. In general globally the total space might fail to be Hausdorff. But if all fibres of a real Lie algebra bundle over a topological space are mutually isomorphic as Lie algebras, then it is a locally trivial Lie algebra bundle. This result was proved by proving that the real orbit of a real point under an algebraic group is open in the real part of its complex orbit. Suppose the base space is Hausdorff and fibers of total space are isomorphic as Lie algebras then there exists a Hausdorff Lie group bundle over the same base space whose Lie algebra bundle is isomorphic to the given Lie algebra bundle. Every semi simple Lie algebra bundle is locally trivial. Hence there exist a Hausdorff Lie group bundle over the same base space whose Lie algebra bundle is isomorphic to the given Lie algebra bundle.
See also
Algebra bundle
Adjoint bundle |
https://en.wikipedia.org/wiki/Decision-making%20models | Decision-making as a team is a scientific process when that decision will affect a policy affecting an entity. Decision-making models are used as a method and process to fulfill the following objectives:
Every team member is clear about how a decision will be made
The roles and responsibilities for the decision making
Who will own the process to make the final decision
These models help the team to plan the process and the agenda for each decision-making meeting, and the understanding of the process and collaborative approach helps in achieving the support of the team members for the final decision to ensure commitment for the same.
Types
There are several models of decision-making:
Economic rationality model
When using this model, the following conditions are assumed.
The decision will be completely rational in a means-ends sense.
There is a complete and consistent system of preferences that allows a choice among alternatives.
There is a complete awareness of all the possible alternatives
Probability calculations are neither frightening nor mysterious
There are no limits to the complexity of computations that can be performed to determine the best alternatives
According to Kuwashima (2014, p. 1) in an organizational decision-making context, the decision-maker approaches the problem in a solely objective way and avoids all subjectivity. Moreover, the rational choice theory revolves around the idea that every individual attempt to maximize their own personal happiness or satisfaction gained from a good or service. This basic idea leads to the “rational” decision model, which is often used in the decision-making process. (Bergmiller, McCright and Weisenborn 2011, p.2)
Simon's bounded rationality model
To present a more realistic alternative to the economic rationality model, Herbert Simon proposed an alternative model. He felt that management decision-making behavior could be described as follows:
In choosing between alternatives, the manager attempts |
https://en.wikipedia.org/wiki/Matrix%20determinant%20lemma | In mathematics, in particular linear algebra, the matrix determinant lemma computes the determinant of the sum of an invertible matrix A and the dyadic product, uvT, of a column vector u and a row vector vT.
Statement
Suppose A is an invertible square matrix and u, v are column vectors. Then the matrix determinant lemma states that
Here, uvT is the outer product of two vectors u and v.
The theorem can also be stated in terms of the adjugate matrix of A:
in which case it applies whether or not the square matrix A is invertible.
Proof
First the proof of the special case A = I follows from the equality:
The determinant of the left hand side is the product of the determinants of the three matrices. Since the first and third matrix are triangular matrices with unit diagonal, their determinants are just 1. The determinant of the middle matrix is our desired value. The determinant of the right hand side is simply (1 + vTu). So we have the result:
Then the general case can be found as:
Application
If the determinant and inverse of A are already known, the formula provides a numerically cheap way to compute the determinant of A corrected by the matrix uvT. The computation is relatively cheap because the determinant of A + uvT does not have to be computed from scratch (which in general is expensive). Using unit vectors for u and/or v, individual columns, rows or elements of A may be manipulated and a correspondingly updated determinant computed relatively cheaply in this way.
When the matrix determinant lemma is used in conjunction with the Sherman–Morrison formula, both the inverse and determinant may be conveniently updated together.
Generalization
Suppose A is an invertible n-by-n matrix and U, V are n-by-m matrices. Then
In the special case this is the Weinstein–Aronszajn identity.
Given additionally an invertible m-by-m matrix W, the relationship can also be expressed as
See also
The Sherman–Morrison formula, which shows how to update the inver |
https://en.wikipedia.org/wiki/Hypohidrosis | Hypohidrosis is a disorder in which a person exhibits diminished sweating in response to appropriate stimuli. In contrast with hyperhidrosis, which is a socially troubling yet often benign condition, the consequences of untreated hypohidrosis include hyperthermia, heat stroke and death. An extreme case of hypohidrosis in which there is a complete absence of sweating and the skin is dry is termed anhidrosis.
Causes
The causes are the following:
Diagnosis
Sweat is readily visualized by a topical indicator such as iodinated starch (Minor test) or sodium alizarin sulphonate, both of which undergo a dramatic colour change when moistened by sweat. A thermoregulatory sweat test can evaluate the body’s response to a thermal stimulus by inducing sweating through a hot box ⁄ room, thermal blanket or exercise. Failure of the topical indicator to undergo a colour change during thermoregulatory sweat testing indicates hypohidrosis, and further tests may be required to localize the lesion.
Magnetic resonance imaging of the brain and ⁄ or spinal cord is the best modality for evaluation when the lesion is suspected to be localized to the central nervous system.
Skin biopsies are useful when anhidrosis occurs as part of a dermatological disorder. Biopsy results may reveal the sweat gland destruction, necrosis or fibrosis, in addition to the findings of the primary dermatological disorder.
Management
The treatment options for hypohidrosis and anhidrosis are limited. Those with hypohidrosis should avoid drugs that can aggravate the condition (see "Medications", under ). They should limit activities that raise the core body temperature and if exercises are to be performed, they should be supervised and be performed in a cool, sheltered and well-ventilated environment. In instances where the cause is known, treatment should be directed at the primary pathology. In autoimmune diseases, such as Sjögren syndrome and systemic sclerosis, treatment of the underlying disease using immunos |
https://en.wikipedia.org/wiki/Metadyne | A metadyne is a direct current electrical machine with two pairs of brushes. It can be used as an amplifier or rotary transformer. It is similar to a third brush dynamo but has additional regulator or "variator" windings. It is also similar to an amplidyne except that the latter has a compensating winding which fully counteracts the effect of the flux produced by the load current. The technical description is "a cross-field direct current machine designed to utilize armature reaction". A metadyne can convert a constant-voltage input into a constant-current, variable-voltage output.
History
The word metadyne is derived from the Greek words for conversion of power. While the name is believed to have been coined by Joseph Maximus Pestarini (Italian language Giuseppe Massimo Pestarini) in a paper which he submitted to the Montefiore International Contest at Liège, Belgium in 1928, the type of machine which it described had been known since the 1880s. The first known British patent for a direct-current, cross-field generator was obtained by A. I. Gravier of Paris in 1882, and two further patents were obtained by E. Rosenberg in 1904 and 1907. Rosenberg later became the chief electrical engineer for Metropolitan-Vickers, and his machine produced a cross field by applying a short-circuit to an additional set of brushes. M. Osnos looked at the practical arrangements for several such machines in 1907, and in the same year, Felton and Guilleaume obtained a British patent, number 26,607, which described auxiliary windings, armature windings and multiple commutators, although all in fairly general terms. He also indicated that they could be used to transform a constant voltage into a constant current. Other patents were obtained prior to 1910 by Mather & Platt, Brown Boverei and Bruce Peebles.
Pestarini worked on developing the theory of such machines between 1922 and 1930, although he concentrated on their static characteristics, rather than their dynamic characteristics. H |
https://en.wikipedia.org/wiki/Transient%20state | A system is said to be transient or in a transient state when a process variable or variables have been changed and the system has not yet reached a steady state. The time taken for the circuit to change from one steady state to another steady state is called the transient time.
Examples
Chemical Engineering
When a chemical reactor is being brought into operation, the concentrations, temperatures, species compositions, and reaction rates are changing with time until operation reaches its nominal process variables.
Electrical engineering
When a switch is flipped in an appropriate electrical circuit containing a capacitor or inductor, the component draws out the resulting change in voltage or current (respectively), causing the system to take a substantial amount of time to reach a new steady state.
We can define a transient by saying that when a quantity is at rest or in uniform motion and a change in time takes place , changing the existing state , a transient has taken place.
When a SCR (four-layer PNPN Device) is switched on we have the problem of transients occurring as a result of high values of current and voltage oscillating around the point before normal levels are obtained again. Filtering can prevent damage to SCR by means of LC filters, zener diodes, trans-zorps, and varistors.
See also
Attractor
Carrying capacity
Control theory
Dynamical system
Ecological footprint
Economic growth
Engine test stand
Equilibrium point
List of types of equilibrium
Evolutionary economics
Growth curve
Herman Daly
Homeostasis
Lead-lag compensator
Limit cycle
Limits to Growth
Population dynamics
Race condition
Simulation
State function
Steady state
Steady state economy
Steady State theory
Systems theory
Thermodynamic equilibrium
Transient modelling
Transient response |
https://en.wikipedia.org/wiki/Transient%20%28computer%20programming%29 | In computer programming, transient is a property of any element in the system that is temporary. The term applies to transient applications, i.e. software for the end-user which is displayed with a transient application posture; transient data, which is discarded after it is no longer needed by the computation; and transient code which are subroutines or software components that are loaded in the system only for a fraction of the total run time.
Examples of applications of the term are described below.
Java
In the Java programming language, transient is a keyword used as a field modifier. When a field is declared transient, it would not be serialized even if the class to which it belongs is serialized. In Java, methods, classes and interfaces cannot be declared as transient, because they are never serialized.
In Hibernate and other persistence systems, transient describes an object that has been instantiated, but is not associated with a Hibernate session, i. e. the object resides in memory but is not being persisted.
X
In the X Window System, a window is said to be transient for another window if it belongs to that other window and may not outlast it: a dialog box, such as an alert message, is a common example. This should not be confused with a window containing another window: contained windows lie entirely within their parents, but transients are separate windows which can generally be moved freely around the screen. Transient windows may be treated specially by the window manager, and unlike top-level windows (which can require user placement, as in twm), must never require any user interaction on appearing.
Operating systems
Transient also refers to a module that, once loaded into main memory, is expected to remain in memory for a short time. Today, the term is rarely used, and may be obsolete. The term Overlay is commonly used instead, and refer to a program module that is brought to memory when it is needed by the running program and then replaced w |
https://en.wikipedia.org/wiki/Security%20Protocols%20Open%20Repository | SPORE, the Security Protocols Open Repository, is an online library of security protocols with comments and links to papers. Each protocol is downloadable in a variety of formats, including rules for use with automatic protocol verification tools. All protocols are described using BAN logic or the style used by Clark and Jacob, and their goals. The database includes details on formal proofs or known attacks, with references to comments, analysis & papers. A large number of protocols are listed, including many which have been shown to be insecure.
It is a continuation of the seminal work by John Clark and Jeremy Jacob.
They seek contributions for new protocols, links and comments.
See also
Cryptographic nonce
Cryptography
Important books, papers, and open problems in cryptography.
List of cryptography topics.
Public-key cryptography
Short and long lists of cryptographers.
Symmetric-key algorithm |
https://en.wikipedia.org/wiki/Network%20traffic | Network traffic or data traffic is the amount of data moving across a network at a given point of time. Network data in computer networks is mostly encapsulated in network packets, which provide the load in the network. Network traffic is the main component for network traffic measurement, network traffic control and simulation.
Network traffic control - managing, prioritizing, controlling or reducing the network traffic
Network traffic measurement - measuring the amount and type of traffic on a particular network
Network traffic simulation - to measure the efficiency of a communications network
Traffic generation model - is a stochastic model of the traffic flows or data sources in a communication computer network.
Proper analysis of network traffic provides the organization with the network security as a benefit - unusual amount of traffic in a network is a possible sign of an attack. Network traffic reports provide valuable insights into preventing such attacks.
Traffic volume is a measure of the total work done by a resource or facility, normally over 24 hours, and is measured in units of erlang-hours. It is defined as the product of the average traffic intensity and the time period of the study.
Traffic volume = Traffic intensity × time
A traffic volume of one erlang-hour can be caused by two circuits being occupied continuously for half an hour or by a circuit being half occupied (0.5 erlang) for a period of two hours. Telecommunication operators are vitally interested in traffic volume, as it directly dictates their revenue. |
https://en.wikipedia.org/wiki/Benedita%20Barata%20da%20Rocha | Benedita Barata da Rocha (24 February 1949 – 2 October 2021) was a Portuguese immunologist.
She earned her M.D. 1972 from the University of Lisbon, and her Ph.D. 1978 from the University of Glasgow, Scotland, UK. She was "directeur de recherche classe exceptionel" (DRCE) of the CNRS and director of a research unit of the INSERM at the Necker Institute, Paris, France. Her major scientific contributions are in the areas of T cell immune tolerance, T cell memory and development of intraepithelial lymphocytes.
In 2007 she received the CNRS Silver Medal award and in 2009 a European Research Council advanced grant.
She published more than 100 research articles.
Major works |
https://en.wikipedia.org/wiki/OMII-UK | OMII-UK is an open-source software organisation for the UK research community.
OMII-UK have a number of roles within the UK research community: helping new users get started with E-research, providing the software that is needed and developing that software if it does not exist. OMII-UK also help to guide the development of E-research by liaising with national and international organisations, e-Research groups, standards' groups, and the researchers themselves.
Funding
OMII-UK is funded by the Engineering and Physical Sciences Research Council (EPSRC) and Jisc.
Project partners
OMII-UK is a collaboration between three bodies:
the School of Electronics and Computer Science at the University of Southampton
the Open Grid Services Architecture (OGSA)-DAI project at the National e-Science Centre and EPCC
the myGrid project at the School of Computer Science at the University of Manchester
Project history
The OMII (Open Middleware Infrastructure Institute) started at the University of Southampton in January 2004. In January 2006, the Southampton group joined forces with the established myGrid and OGSA-DAI projects to form OMII-UK - an integral part of the UK e-Science programme.
See also
e-Science
Open Grid Forum (OGF)
Job Submission Description Language (JSDL)
Business Process Execution Language (BPEL)
External links
OMII-UK
Engineering and Physical Sciences Research Council
Grid computing
Information technology management
Jisc
Middleware |
https://en.wikipedia.org/wiki/PicoChip | Picochip was a venture-backed fabless semiconductor company based in Bath, England, founded in 2000. In January 2012 Picochip was acquired by Mindspeed Technologies, Inc and subsequently by Intel.
The company was active in two areas, with two distinct product families.
Picochip was one of the first companies to start developing solutions for small cell basestation (femtocells), for homes and offices. These help combat reception issues such as: dropped calls, poor sound quality, delays, and slow downloads. The idea is to increase the capacity of cellular networks and to address coverage holes.
Multi-core DSP
Picochip developed a multi-core digital signal processor, the picoArray. This integrates 250–300 individual DSP cores onto a single die (depending on the specific product) and as such it can be described as a Massively parallel processor array. Each of these cores is a 16-bit processor with Harvard architecture, local memory and 3-way VLIW. Although each device contained 250–300 processors, the architecture allowed devices to be connected to form far larger systems, in some cases with tens of thousands of cores.
The company had three multi-core DSP products (PC202 / 203 / 205) that delivered approximately 40 GMACS and 200 GIPS of performance. The earlier PC102 is obsolete.
The programming model allows each processor to be coded independently (in ANSI C or assembler) and then to communicate over an any:any interconnect mesh. The communication flows are fixed at compile time, not dynamically at run time (analogous to place & route of an FPGA but at higher level of abstraction). This can be described as communicating sequential processes. Each process maps to a processor, which is fully independent from other processors with "encapsulation", with interaction only through defined message passing and data flows through the mesh. This architecture is also related to object-oriented programming concepts. Notably, the development environment is deterministic: sim |
https://en.wikipedia.org/wiki/Growing%20block%20universe | The growing block universe theory of time (or the growing block view), states that the past and present both exist, and the future as yet does not. The present is an objective property, to be compared with a moving spotlight. By the passage of time more of the world comes into being; therefore, the block universe is said to be growing. The growth of the block is supposed to happen in the present, a very thin slice of spacetime, where more of spacetime is continually coming into being. Growing block theory should not be confused with block universe theory, also known as eternalism.
The growing block view is an alternative to both eternalism (according to which past, present, and future all exist) and presentism (according to which only the present exists). It is held to be closer to common-sense intuitions than the alternatives. C. D. Broad was a proponent of the theory (1923). Some modern defenders are Michael Tooley (in 1997) and Peter Forrest (in 2004).
Fabrice Correia and Sven Rosenkranz have developed their own distinctive view of this theory (2015).
The theory
Broad first proposed the theory in 1923. He described the theory as follows:
It will be observed that such a theory as this accepts the reality of the present and the past, but holds that the future is simply nothing at all. Nothing has happened to the present by becoming past except that fresh slices of existence have been added to the total history of the world. The past is thus as real as the present. On the other hand, the essence of a present event is, not that it precedes future events, but that there is quite literally nothing to which it has the relation of precedence. The sum total of existence is always increasing, and it is this which gives the time-series a sense as well as an order. A moment t is later than a moment t' if the sum total of existence at t includes the sum total of existence at t' together with something more.
This dynamic theory of time conforms with the common-sense |
https://en.wikipedia.org/wiki/Monosodium%20phosphate | Monosodium phosphate (MSP), also known as monobasic sodium phosphate and sodium dihydrogen phosphate, is an inorganic compound of sodium with a dihydrogen phosphate (H2PO4−) anion. One of many sodium phosphates, it is a common industrial chemical. The salt exists in an anhydrous form, as well as mono- and dihydrates.
Production and reactions
The salt is obtained by partial neutralization of phosphoric acid. The pKa of monosodium phosphate is 6.8-7.2 (depending on the physicochemical characteristics during pKa determination).
Heating this salt above 169 °C gives the corresponding sodium acid pyrophosphate:
2 NaH2PO4 → Na2H2P2O7 + H2O
When heated at 550 °C, anhydrous trisodium trimetaphosphate results:
Uses
Phosphates are often used in foods and in water treatment. The pH of such formulations is generally adjusted by mixtures of various sodium phosphates, such as this salt.
The sodium chloride equivalent value, or E-Value, is 0.49. It is soluble in 4.5 parts water.
Food additive
It is added in animal feed, toothpaste, and evaporated milk. It is used as a thickening agent and emulsifier.
Detection of magnesium
Monosodium phosphate is used to detect the presence of magnesium ions in salts. Formation of a white precipitate on the addition of ammonium chloride, ammonium hydroxide and monosodium phosphate to an aqueous or dilute HCl solution of the salt indicates presence of magnesium ions.
Notes
Phosphates
Sodium compounds
Edible thickening agents |
https://en.wikipedia.org/wiki/Hierarchical%20temporal%20memory | Hierarchical temporal memory (HTM) is a biologically constrained machine intelligence technology developed by Numenta. Originally described in the 2004 book On Intelligence by Jeff Hawkins with Sandra Blakeslee, HTM is primarily used today for anomaly detection in streaming data. The technology is based on neuroscience and the physiology and interaction of pyramidal neurons in the neocortex of the mammalian (in particular, human) brain.
At the core of HTM are learning algorithms that can store, learn, infer, and recall high-order sequences. Unlike most other machine learning methods, HTM constantly learns (in an unsupervised process) time-based patterns in unlabeled data. HTM is robust to noise, and has high capacity (it can learn multiple patterns simultaneously). When applied to computers, HTM is well suited for prediction, anomaly detection, classification, and ultimately sensorimotor applications.
HTM has been tested and implemented in software through example applications from Numenta and a few commercial applications from Numenta's partners.
Structure and algorithms
A typical HTM network is a tree-shaped hierarchy of levels (not to be confused with the "layers" of the neocortex, as described below). These levels are composed of smaller elements called regions (or nodes). A single level in the hierarchy possibly contains several regions. Higher hierarchy levels often have fewer regions. Higher hierarchy levels can reuse patterns learned at the lower levels by combining them to memorize more complex patterns.
Each HTM region has the same basic function. In learning and inference modes, sensory data (e.g. data from the eyes) comes into bottom-level regions. In generation mode, the bottom level regions output the generated pattern of a given category. The top level usually has a single region that stores the most general and most permanent categories (concepts); these determine, or are determined by, smaller concepts at lower levels—concepts that are more res |
https://en.wikipedia.org/wiki/Carbamoyl%20phosphate%20synthetase | Carbamoyl phosphate synthetase catalyzes the ATP-dependent synthesis
of carbamoyl phosphate from glutamine () or ammonia () and bicarbonate. This enzyme catalyzes the reaction of ATP and bicarbonate to produce carboxy phosphate and ADP. Carboxy phosphate reacts with ammonia to give carbamic acid. In turn, carbamic acid reacts with a second ATP to give carbamoyl phosphate plus ADP.
It represents the first committed step in pyrimidine and arginine biosynthesis in prokaryotes and eukaryotes, and in the urea cycle in most terrestrial vertebrates. Most prokaryotes carry one form of CPSase that participates in both arginine and pyrimidine biosynthesis, however certain bacteria can have separate forms.
There are three different forms that serve very different functions:
Carbamoyl phosphate synthetase I (mitochondria, urea cycle)
Carbamoyl phosphate synthetase II (cytosol, pyrimidine metabolism).
Carbamoyl phosphate synthetase III (found in fish).
Mechanism
Carbamoyl phosphate synthase has three main steps in its mechanism and is, in essence, irreversible.
Bicarbonate ion is phosphorylated with ATP to create .
The then reacts with ammonia to form carbamic acid, releasing inorganic phosphate.
A second molecule of ATP then phosphorylates carbamic acid, creating carbamoyl phosphate.
The activity of the enzyme is known to be inhibited by both Tris and HEPES buffers.
Structure
Carbamoyl phosphate synthase (CPSase) is a heterodimeric enzyme composed of a small and a large subunit (with the exception of CPSase III, which is composed of a single polypeptide that may have arisen from gene fusion of the glutaminase and synthetase domains). CPSase has three active sites, one in the small subunit and two in the large subunit. The small subunit contains the glutamine binding site and catalyses the hydrolysis of glutamine to glutamate and ammonia, which is in turn used by the large chain to synthesize carbamoyl phosphate. The small subunit has a 3-layer beta/beta/alpha str |
https://en.wikipedia.org/wiki/WebMethods%20Glue | webMethods Glue is an enterprise web services platform from webMethods. It provides web services/SOAP capabilities to existing Java and C/C++ applications.
Developers use the Java-based product to add enterprise web services integration to legacy applications with reduced programming effort. It is an embeddable product (small footprint) that turns a non-web service application into one that exposes its functionality as a web services.
Similar to the open source Apache Axis, the Glue product provides a layer of web service interoperability with existing applications.
Product features
webMethods Glue features include:
Little or no coding to expose application functionality as a web service
Standalone operation if required (does not need an application server)
Fast local messaging
Transparent Java/XML integration
Web services standards support
Small memory footprint
Product history
Created by The Mind Electric, GLUE—as it was then named—was the company's flagship product. They released it in two forms: a free, unsupported "standard" version, and a company-supported but commercially licensed "professional" edition.
In September 2003 GLUE featured in a Microsoft Press book, Microsoft .NET and J2EE Interoperability Toolkit.
webMethods acquired the product as part of its merger with The Mind Electric. The merger resulted in rebranding the product with the webMethods prefix to become webMethods Glue.
The webMethods Glue product 6.5.x maintenance ended on May 31, 2010, and support ended a year later.
Release history
GLUE 3.0 - Aug 2002
GLUE 4.0 - April 2003
GLUE 4.1 - June 2003
Technologies/standards
HTTP, Servlets, XML, SOAP, WSDL, and UDDI |
https://en.wikipedia.org/wiki/Audio%20router | An audio router is a device that transports audio signals from inputs to outputs.
Inputs and Outputs
The number of inputs and outputs varies dramatically. The way routers are described is normally number of inputs by number of outputs e.g. 2x1, 256x256.
Signals
The type of signals transported - switched can be analogue - Analog - audio signals or Digital. Digital audio usually is in the AES/EBU standard for broadcast use. Broadband routers can route more than one signal type e.g. analogue or more than one type of digital.
Crosspoints
Because any of the inputs can be routed to any output, the internal arrangement of the router is arranged as a number of crosspoints which can be activated to pass the corresponding signal to the desired output.
Some Manufacturers of audio routers
Lawo
Datavideo
Imagine Communications
AEQ
FOR-A
Klotz Digital
NVISION
Panasonic
Philips
Ross Video
Snell & Wilcox
Sony
Thomson Grass Valley
Utah Scientific
Matrix Switch Corporation
See also
Video router
Vision mixer
Television technology
Television terminology |
https://en.wikipedia.org/wiki/Dynamic%20aperture | In acoustics, dynamic aperture is analogous to aperture in photography. The arrays in side-scan sonar can be programmed to transmit just a few elements at a time or all the elements at once. The more elements transmitting, the narrower the beam and the better the resolution.
The ratio of the imaging depth to the aperture size is known as the F-number. Dynamic aperture is keeping this number constant by growing the aperture with the imaging depth until the physical aperture cannot be increased. A modern medical ultrasound machine has a typical F-number of 0.5.
Side Scan Sonar systems produce images by forming angular “beams”. Beam width is determined by length of the sonar array, narrower beams resolve finer detail. Longer arrays with narrower beams provide finer spatial resolution.
Acoustics |
https://en.wikipedia.org/wiki/Flag%20of%20Kosovo | The flag of the Republic of Kosovo was adopted by the Assembly of the Republic of Kosovo immediately following the unilateral declaration of independence of Kosovo on 17 February 2008. The flag design emerged from an international competition, organized by the United Nations-backed Kosovo Unity Team, which attracted almost one thousand entries. The winning design was proposed by Muhamer Ibrahimi. It shows six white stars in an arc above a golden map of Kosovo, all on a blue field. The stars symbolize Kosovo's six major ethnic groups: Albanians, Serbs, Bosniaks, Turks, Romani, and Gorani.
Before the declaration of independence, Kosovo had come under the administration of the United Nations and used the UN flag for official purposes. The Serb and Albanian populations had used their own national flags since the 1945–1992 Socialist Yugoslavia period. Ethnic Serbs used a red, blue and white tricolor, which also forms the basis of the flag of Serbia. The ethnic Albanian population have used the flag of Albania since the 1960s as their ethnic flag. Both these flags can still be seen in use within Kosovo.
Serbia has not recognized the independence of Kosovo and continues to claim the area as the Autonomous Province of Kosovo and Metohija. Unlike the case of the autonomous province of Vojvodina, the Serbian authorities have not adopted a unique flag to represent this claimed province, using the flag of Serbia instead.
Design and use
The flag of Kosovo has a blue background, charged with a map of Kosovo and six stars. The stars are officially meant to symbolize Kosovo's six major ethnic groups: Albanians, Serbs, Bosniaks, Turks, Romani (often grouped with the Ashkali and Egyptians) and Gorani. Unofficially, the stars are sometimes said to represent the six regions, which according to Albanian ultra-nationalist ideology, make up Greater Albania: Albania, Kosovo, western parts of North Macedonia, parts of northern Greece, parts of Montenegro and Preševo Valley in southern S |
https://en.wikipedia.org/wiki/Booster%20%28electric%20power%29 | A power booster is a combination of motor-mechanical power amplifier- generator. For example a 30kw motor with the power amplifier could power a 100kw generator. This power booster is now commercially available
Line booster
In the days of direct current mains, voltage drop along the line was a problem so line boosters were used to correct it. Suppose that the mains voltage was 110 V. Houses near the power station would receive 110 volts but those remote from the power station might receive only 100 V so a line booster would be inserted at an appropriate point to "boost" the voltage. It consisted of a motor, connected in parallel with the mains, driving a generator, in series with the mains. The motor ran at the depleted mains voltage of 100 V and the generator added another 10 V to restore the voltage to 110 V. This was an inefficient system and was made obsolete by the development of alternating current mains, which allowed for high-voltage distribution and voltage regulation by transformers.
Milking booster
Again in the days of direct current mains, power stations often had large lead-acid batteries for load balancing. These supplemented the steam-powered generators during peak periods and were re-charged off-peak. Sometimes one cell in the battery would become "sick" (faulty, reduced capacity) and a "milking booster" would be used to give it an additional charge and restore it to health. The milking booster was so-called because it "milked" the healthy cells in the battery to give an extra charge to the faulty one. The motor side of the booster was connected across the whole battery but the generator side was connected only across the faulty cell. During discharge periods the booster supplemented the output of the faulty cell.
Reversible booster
Before solid-state technology became available, reversible boosters were sometimes used for speed control in DC electric locomotives. The boosters were called reversible, because they could either increase |
https://en.wikipedia.org/wiki/Vidoop | Vidoop LLC was a privately held company based in Portland, Oregon. Its flagship product was Vidoop Secure, a login solution designed to function without traditional passwords, which Vidoop claimed was resistant to brute force, keystroke logging, phishing, and some man-in-the-middle attacks. On 30 May 2009, Vidoop announced that it was going out of business.
Founding and Launch
Vidoop was founded in 2006 in Tulsa, Oklahoma. As of March 2006 it had 4 employees and would initially reveal only that it was developing a novel login solution that hides an access code in plain sight. After over a year of secretive development and testing, the company launched its product, Vidoop Secure, at the Web 2.0 Expo in San Francisco, California on 2007-04-17. Luke Sontag, a co-founder, gave a presentation at the expo demonstrating the technology and further announced that an unnamed Fortune 500 company would be replacing its login system with Vidoop by July 2007.
Products
Vidoop's core technology is the Vidoop Dynamic Image Grid, a login tool that powers Vidoop Secure and thus myVidoop.com. The company also sells advertising space, allowing a company to place its products as images in the grid. There are currently two multi-national advertisers: Smart USA (a division of Daimler) and ConocoPhillips (Phillips66, Conoco, and 76 brand gas stations). One regional advertiser: Mazzio's. And one local advertiser: Jackie Cooper Imports (A local Tulsa, OK auto dealer).
Vidoop Secure
Vidoop Secure is a user login technology based on categorized images. When a user enrolls in a system implementing the technology, he chooses from several categories of images (such as airplanes, cars, or keys). Furthermore, the user's computer is "activated" with a cookie, which is only provided upon the user's confirmation of a code transmitted either by email or by phone via voice or text message. At the time of login, if the cookie is found, a grid of images is displayed that includes pictures belongin |
https://en.wikipedia.org/wiki/Origami%20paper | Origami paper is used to fold origami, the art of paper folding. The only real requirement of the folding medium is that it must be able to hold a crease, but should ideally also be thinner than regular paper for convenience when multiple folds over the same small paper area are required (e.g. such as would be the case if creating an origami bird's "legs", "feet", and "beak").
Kami
Kami, or koiy paper, is the cheapest paper made specifically for origami, and the most widely available. It was developed for use in schools. The word kami is simply Japanese for paper, but it has acquired this specific meaning.
Kami is thin and easy to fold. It is usually printed only on one side, with a solid color or pattern. These patterns can be as simple as a gradation from red to blue, or as complex as a multi-colored kimono pattern of flowers and cranes with gold foil embellishments. Kami comes in several sizes, but standard sizes include 75 × 75 mm (about 3 × 3 inches), 6-inch squares and 10-inch squares.
Paper-backed foil
This medium is a slightly more expensive, flashier, paper that is good for retaining creases called paper-backed foil paper, Japanese foil, or simply foil. Foil paper is composed of a thin layer of foil adhered to an extremely thin sheet of paper. The most common colors are silver and gold, but any color is possible in foil paper including bright pink, blue and copper. In many multi-color packs, one sheet each of silver and gold paper is included. These are usually placed on the bottom end of the string if used in a thousand origami cranes.
Washi
Washi (wa = Japanese and shi = paper · washi = Japanese paper) is traditionally a fine handmade thin paper coveted by artists and craftspeople. Washi is made with renewable long-fibered crops and is very strong even when thin. Some washi does not hold a sharp fold due to the extremely long and thick fibers of the paper. Occasionally you will find strands of the long fibers (often kozo) in washi. Washi is also accep |
https://en.wikipedia.org/wiki/Positively%20separated%20sets | In mathematics, two non-empty subsets A and B of a given metric space (X, d) are said to be positively separated if the infimum
(Some authors also specify that A and B should be disjoint sets; however, this adds nothing to the definition, since if A and B have some common point p, then d(p, p) = 0, and so the infimum above is clearly 0 in that case.)
For example, on the real line with the usual distance, the open intervals (0, 2) and (3, 4) are positively separated, while (3, 4) and (4, 5) are not. In two dimensions, the graph of y = 1/x for x > 0 and the x-axis are not positively separated. |
https://en.wikipedia.org/wiki/Metric%20outer%20measure | In mathematics, a metric outer measure is an outer measure μ defined on the subsets of a given metric space (X, d) such that
for every pair of positively separated subsets A and B of X.
Construction of metric outer measures
Let τ : Σ → [0, +∞] be a set function defined on a class Σ of subsets of X containing the empty set ∅, such that τ(∅) = 0. One can show that the set function μ defined by
where
is not only an outer measure, but in fact a metric outer measure as well. (Some authors prefer to take a supremum over δ > 0 rather than a limit as δ → 0; the two give the same result, since μδ(E) increases as δ decreases.)
For the function τ one can use
where s is a positive constant; this τ is defined on the power set of all subsets of X. By Carathéodory's extension theorem, the outer measure can be promoted to a full measure; the associated measure μ is the s-dimensional Hausdorff measure. More generally, one could use any so-called dimension function.
This construction is very important in fractal geometry, since this is how the Hausdorff measure is obtained. The packing measure is superficially similar, but is obtained in a different manner, by packing balls inside a set, rather than covering the set.
Properties of metric outer measures
Let μ be a metric outer measure on a metric space (X, d).
For any sequence of subsets An, n ∈ N, of X with
and such that An and A \ An+1 are positively separated, it follows that
All the d-closed subsets E of X are μ-measurable in the sense that they satisfy the following version of Carathéodory's criterion: for all sets A and B with A ⊆ E and B ⊆ X \ E,
Consequently, all the Borel subsets of X — those obtainable as countable unions, intersections and set-theoretic differences of open/closed sets — are μ-measurable. |
https://en.wikipedia.org/wiki/Liver%20fluke | Liver fluke is a collective name of a polyphyletic group of parasitic trematodes under the phylum Platyhelminthes.
They are principally parasites of the liver of various mammals, including humans. Capable of moving along the blood circulation, they can occur also in bile ducts, gallbladder, and liver parenchyma. In these organs, they produce pathological lesions leading to parasitic diseases. They have complex life cycles requiring two or three different hosts, with free-living larval stages in water.
Biology
The body of liver flukes is leaf-like and flattened. The body is covered with a tegument. They are hermaphrodites having complete sets of both male and female reproductive systems. They have simple digestive systems and primarily feed on blood. The anterior end is the oral sucker opening into the mouth. Inside, the mouth leads to a small pharynx which is followed by an extended intestine that runs through the entire length of the body. The intestine is heavily branched and the anus is absent. Instead, the intestine runs along an excretory canal that opens at the posterior end. Adult flukes produce eggs that are passed out through the excretory pore. The eggs infect different species of snails (as intermediate hosts) in which they grow into larvae. The larvae are released into the environment from where the definitive hosts (humans and other mammals) get the infection. In some species, another intermediate host is required, generally a cyprinid fish. In this case, the definitive hosts are infected from eating infected fish. Hence, they are food-borne parasites.
Pathogenicity
Liver fluke infections cause serious medical and veterinary diseases. Fasciolosis of sheep, goats and cattle, is the major cause of economic losses in dairy and meat industry. Fasciolosis of humans produces clinical symptoms such as fever, nausea, swollen liver, extreme abdominal pain, jaundice and anemia.
Clonorchiasis and opisthorchiasis (due to Opisthorchis viverrini) are particularly |
https://en.wikipedia.org/wiki/Frailty%20syndrome | Frailty is a common geriatric syndrome that embodies an elevated risk of catastrophic declines in health and function among older adults. Frailty is a condition associated with ageing, and it has been recognized for centuries. It is a marker of a more widespread syndrome of frailty, with associated weakness, slowing, decreased energy, lower activity, and, when severe, unintended weight loss. As a frequent clinical syndrome in the elderly, various health risks are linked to health deterioration and frailty in older age, such as falls, disability, hospitalization, and mortality. Generally, frailty refers to older adults who lose independence. It also links to the experiences of losing dignity due to social and emotional isolation risk. Frailty has been identified as a risk factor for the development of dementia.
As a population ages, a central focus of geriatricians and public health practitioners is to understand, and then beneficially intervene on, the factors and processes that put elders at such risk, especially the increased vulnerability to stressors (e.g. extremes of heat and cold, infection, injury, or even changes in medication) that characterizes many older adults.
Geriatric syndromes related to frailty
Sarcopenia
Sarcopenia is the degenerative loss of skeletal muscle mass, quality, and strength associated with aging. The rate of muscle loss is dependent on exercise level, co-morbidities, nutrition and other factors. Sarcopenia can lead to reduction in functional status and cause significant disability from increased weakness. The muscle loss is related to changes in muscle synthesis signalling pathways although is incompletely understood. The cellular mechanisms are distinct from other types of muscle atrophy such as cachexia, in which muscle is degraded through cytokine-mediated degradation although both conditions may co-exist.
Osteoporosis
Osteoporosis is an age-related disease of bone that leads to an increased risk of fracture. In osteoporosis th |
https://en.wikipedia.org/wiki/Deoxycytidine%20monophosphate | Deoxycytidine monophosphate (dCMP), also known as deoxycytidylic acid or deoxycytidylate in its conjugate acid and conjugate base forms, respectively, is a deoxynucleotide, and one of the four monomers that make up DNA. In a DNA double helix, it will base pair with deoxyguanosine monophosphate.
See also
Cytidine monophosphate
Nucleotides |
https://en.wikipedia.org/wiki/Mobile%20virtual%20private%20network | A mobile virtual private network (mobile VPN or mVPN) is a VPN which is capable of persisting during sessions across changes in physical connectivity, point of network attachment, and IP address. The "mobile" in the name refers to the fact that the VPN can change points of network attachment, not necessarily that the mVPN client is a mobile phone or that it is running on a wireless network.
Mobile VPNs are used in environments where workers need to keep application sessions open at all times, throughout the working day, as they connect via various wireless networks, encounter gaps in coverage, or suspend-and-resume their devices to preserve battery life. A conventional VPN cannot survive such events because the network tunnel is disrupted, causing applications to disconnect, time out, fail, or even the computing device itself to crash. Mobile VPNs are commonly used in public safety, home care, hospital settings, field service management, utilities and other industries. Increasingly, they are being adopted by mobile professionals and white-collar workers.
Comparison with other VPN types
A VPN maintains an authenticated, encrypted tunnel for securely passing data traffic over public networks (typically, the Internet.) Other VPN types are IPsec VPNs, which are useful for point-to-point connections when the network endpoints are known and remain fixed; or SSL VPNs, which provide for access through a Web browser and are commonly used by remote workers.
Makers of mobile VPNs draw a distinction between remote access and mobile environments. A remote-access user typically establishes a connection from a fixed endpoint, launches applications that connect to corporate resources as needed, and then logs off. In a mobile environment, the endpoint changes constantly (for instance, as users roam between different cellular networks or Wi-Fi access points). A mobile VPN maintains a virtual connection to the application at all times as the endpoint changes, handling the necess |
https://en.wikipedia.org/wiki/Cryophorus | A cryophorus is a glass container containing liquid water and water vapor. It is used in physics courses to demonstrate rapid freezing by evaporation. A typical cryophorus has a bulb at one end connected to a tube of the same material. When the liquid water is manipulated into the bulbed end and the other end is submerged into a freezing mixture (such as liquid nitrogen), the gas pressure drops as it is cooled. The liquid water begins to evaporate, producing more water vapor. Evaporation causes the water to cool rapidly to its freezing point and it solidifies suddenly.
Wollaston's cryophorus was a precursor to the modern heat pipe.
History
The cryophorus was first described by William Hyde Wollaston in an 1813 paper titled, "On a method of freezing at a distance." |
https://en.wikipedia.org/wiki/2N7000 | The 2N7000 and BS170 are two different N-channel, enhancement-mode MOSFETs used for low-power switching applications, with different lead arrangements and current ratings. They are sometimes listed together on the same datasheet with other variants 2N7002, VQ1000J, and VQ1000P.
The 2N7000 is a widely available and popular part, often recommended as useful and common components to have around for hobbyist use.
The BS250P is "a good p-channel analog of the 2N7000."
Packaged in a TO-92 enclosure, both the 2N7000 and BS170 are 60 V devices. The 2N7000 can switch 200 mA. The BS170 can switch 500 mA, with a maximum on-resistance of 5 Ω at 10 V Vgs.
The 2N7002 is a part with similar (but not identical) electrical characteristics as the 2N7000 but different package. The 2N7002 is in a TO-236 package, also known as "small outline transistor" SOT-23 surface-mount, which is the most commonly used three-lead surface-mount package.
Applications
The 2N7000 has been referred to as a "FETlington" and as an "absolutely ideal hacker part." The word "FETlington" is a reference to the Darlington-transistor-like saturation characteristic.
A typical use of these transistors is as a switch for moderate voltages and currents, including as drivers for small lamps, motors, and relays. In switching circuits, these FETs can be used much like bipolar junction transistors, but have some advantages:
high input impedance of the insulated gate means almost no gate current is required
consequently no current-limiting resistor is required in the gate input
MOSFETs, unlike PN junction devices (such as LEDs) can be paralleled because resistance increases with temperature, although the quality of this load balance is largely dependent on the internal chemistry of each individual MOSFET in the circuit
The main disadvantages of these FETs over bipolar transistors in switching are the following:
susceptibility to cumulative damage from static discharge prior to installation
circuits with exter |
https://en.wikipedia.org/wiki/Quad%20data%20rate | Quad data rate (QDR, or quad pumping) is a communication signaling technique wherein data are transmitted at four points in the clock cycle: on the rising and falling edges, and at two intermediate points between them. The intermediate points are defined by a second clock that is 90° out of phase from the first. The effect is to deliver four bits of data per signal line per clock cycle.
In a quad data rate system, the data lines operate at twice the frequency of the clock signal. This is in contrast to double data rate systems, in which the clock and data lines operate at the same frequency.
Quad data rate technology was introduced by Intel in its Willamette-core Pentium 4 processor, and was subsequently employed in its Atom, Pentium 4, Celeron, Pentium D and Core 2 processor ranges. This technology has allowed Intel to produce chipsets and processors that can communicate with each other at data rates expected of the traditional front-side bus (FSB) technology running from 400 MT/s to 1600 MT/s, while maintaining a lower and thus more stable actual clock frequency of 100 MHz to 400 MHz.
Background
The reasons for operating in QDR rather than DDR are very different than those cited for operating in DDR rather than single data rate. Going to DDR allowed manufacturers of memory to send data at the same rate as the clock beat (one data-line transition for every clock-line transition), while SDR could only send data at the rate of the clock cycle (one data-line transition for every clock-line rising edge). A naive implementation of QDR would result in the data rate being higher than the clock rate, negating any simple electrical advantage.
The advantages for QDR arise when dealing with bus contention. On a modern computer, there may be several CPUs and several I/O devices, all competing for accesses to the memory. To handle this contention properly, modern systems aim to enable signals to propagate between all connected components within a single clock cycle, |
https://en.wikipedia.org/wiki/Larner%E2%80%93Johnson%20valve | A Larner–Johnson valve is a mechanism used in dams and water pumping to control the flow of water through large pipes. The valve is suited to handling high velocity flow with minimal turbulence, even when partially open, and the actuating force can be provided by the water flow it is controlling. It was manufactured in the early 20th century by the Larner-Johnson Company in the US. The valves are still manufactured in the United Kingdom by Blackhall Engineering Ltd. These valves have been constructed in sizes up to diameter and controlling a hydraulic head of .
In 2009, Blackhall Engineering supplied four 60" bore Larner–Johnson valves to New York City Department of Environmental Protection for the Ashokan Reservoir in upstate New York. Each valve is capable of passing a flow rate of 19 cubic metres/second, which is the equivalent of 19 tons of water per second. The valves control the flow of water out of the Ashokan Reservoir into the Catskill Aqueduct down to New York City.
Operation
The valve is housed within a bulged section of the penstock pipe. The valve mechanism forms a cylindrical body within this pipe, with the water flowing around it. This downstream section of this valve body is conical and free to move axially. When it moves downstream, it seals against a conical surface at the outlet of the valve, closing off the flow. When closed, the valve is held shut by the supply water pressure, providing a good seal.
The valve is hydraulically actuated, by the pressure of the flow that it is controlling. A servomechanism is used to generate the large forces needed for these huge valves, power being derived from the pressure of the water itself. Although the pressure within the pipe cannot be increased above that of the supply, it can be decreased. The pipe cross-section at the lower (downstream) part of the valve is reduced in section compared to that above the valve. By Bernoulli's principle, this increases the flow velocity of the water, thus reducing p |
https://en.wikipedia.org/wiki/Problem%20of%20points | The problem of points, also called the problem of division of the stakes, is a classical problem in probability theory. One of the famous problems that motivated the beginnings of modern probability theory in the 17th century, it led Blaise Pascal to the first explicit reasoning about what today is known as an expected value.
The problem concerns a game of chance with two players who have equal chances of winning each round. The players contribute equally to a prize pot, and agree in advance that the first player to have won a certain number of rounds will collect the entire prize. Now suppose that the game is interrupted by external circumstances before either player has achieved victory. How does one then divide the pot fairly? It is tacitly understood that the division should depend somehow on the number of rounds won by each player, such that a player who is close to winning will get a larger part of the pot. But the problem is not merely one of calculation; it also involves deciding what a "fair" division actually is.
Early solutions
Luca Pacioli considered such a problem in his 1494 textbook Summa de arithmetica, geometrica, proportioni et proportionalità. His method was to divide the stakes in proportion to the number of rounds won by each player, and the number of rounds needed to win did not enter his calculations at all.
In the mid-16th century Niccolò Tartaglia noticed that Pacioli's method leads to counterintuitive results if the game is interrupted when only one round has been played. In that case, Pacioli's rule would award the entire pot to the winner of that single round, though a one-round lead early in a long game is far from decisive. Tartaglia constructed a method that avoids that particular problem by basing the division on the ratio between the size of the lead and the length of the game. This solution is still not without problems, however; in a game to 100 it divides the stakes in the same way for a 65–55 lead as for a 99–89 lead, even t |
https://en.wikipedia.org/wiki/Quartile%20coefficient%20of%20dispersion | In statistics, the quartile coefficient of dispersion is a descriptive statistic which measures dispersion and is used to make comparisons within and between data sets. Since it is based on quantile information, it is less sensitive to outliers than measures such as the coefficient of variation. As such, it is one of several robust measures of scale.
The statistic is easily computed using the first (Q1) and third (Q3) quartiles for each data set. The quartile coefficient of dispersion is:
Example
Consider the following two data sets:
A = {2, 4, 6, 8, 10, 12, 14}
n = 7, range = 12, mean = 8, median = 8, Q1 = 4, Q3 = 12, quartile coefficient of dispersion = 0.5
B = {1.8, 2, 2.1, 2.4, 2.6, 2.9, 3}
n = 7, range = 1.2, mean = 2.4, median = 2.4, Q1 = 2, Q3 = 2.9, quartile coefficient of dispersion = 0.18
The quartile coefficient of dispersion of data set A is 2.7 times as great (0.5 / 0.18) as that of data set B.
See also
Robust measures of scale
Coefficient of variation
Interquartile range
Median absolute deviation |
https://en.wikipedia.org/wiki/Digital%20conversation | A digital conversation is a scripted dialogue between a person and a computer through various digital mediums, including web browsers, PDAs, mobile phones, and interactive television.
Introduction
A digital conversation is scripted by a human, uploaded to a server where it can be accessed as a web service by other humans (consumers, employees etc.) and used to impart information to them, whether that information is advising them on the best camera to buy, helping them tailor make a credit card or engaging them in an interactive book.
A digital conversation can be undertaken simultaneously from multiple digital channels. The means used to access a digital conversation do not matter much as you will be calling the same digital conversation. This means that any changes made to a digital conversation are reflected across all channels immediately which allows digital conversations to evolve.
Digital conversations are designed to engage consumers in a conversation where the goal is to find out what they want and guide them towards achieving it. Many perceive such dialogue marketing as the way forward, and digital conversations provide a solution to delivering this at scale as it moves away from a traditional one-way stream of information with a consumer (offering every consumer the same choices). It also moves towards a dialogue, finding out and giving them what they want. This movement is seen as essential by many:
In the same New York Times article, Robert M. Greenberg then states that he wants to "engage (consumers) in digital conversations that are so entertaining, involving and valuable that they won't want to ignore them." The key word here is "engage". Digital conversations are created to be, in essence, human interactions and dialogue with one human removed. Unlike Bots and Avatars, digital conversations are scripted, and this may well lead to more human-like interactions.
The digital conversation Bio-System
Digital conversations consist of a four-stage "bio |
https://en.wikipedia.org/wiki/Implicit%20curve | In mathematics, an implicit curve is a plane curve defined by an implicit equation relating two coordinate variables, commonly x and y. For example, the unit circle is defined by the implicit equation . In general, every implicit curve is defined by an equation of the form
for some function F of two variables. Hence an implicit curve can be considered as the set of zeros of a function of two variables. Implicit means that the equation is not expressed as a solution for either x in terms of y or vice versa.
If is a polynomial in two variables, the corresponding curve is called an algebraic curve, and specific methods are available for studying it.
Plane curves can be represented in Cartesian coordinates (x, y coordinates) by any of three methods, one of which is the implicit equation given above. The graph of a function is usually described by an equation in which the functional form is explicitly stated; this is called an explicit representation. The third essential description of a curve is the parametric one, where the x- and y-coordinates of curve points are represented by
two functions both of whose functional forms are explicitly stated, and which are dependent on a common parameter
Examples of implicit curves include:
a line:
a circle:
the semicubical parabola:
Cassini ovals (see diagram),
(see diagram).
The first four examples are algebraic curves, but the last one is not algebraic. The first three examples possess simple parametric representations, which is not true for the fourth and fifth examples. The fifth example shows the possibly complicated geometric structure of an implicit curve.
The implicit function theorem describes conditions under which an equation can be solved implicitly for x and/or y – that is, under which one can validly write or . This theorem is the key for the computation of essential geometric features of the curve: tangents, normals, and curvature. In practice implicit curves have an essential drawback: the |
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