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In most shelled molluscs, the shell is large enough for all of the soft parts to be retracted inside when necessary, for protection from predation or from desiccation. However, there are many species of gastropod mollusc in which the shell is somewhat reduced or considerably reduced, such that it offers some degree of protection only to the visceral mass, but is not large enough to allow the retraction of the other soft parts. This is particularly common in the opisthobranchs and in some of the pulmonates, for example in the semi-slugs. Some gastropods have no shell at all, or only an internal shell or internal calcareous granules, and these species are often known as slugs. Semi-slugs are pulmonate slugs with a greatly reduced external shell which is in some cases partly covered by the mantle. | https://en.wikipedia.org/wiki/Mollusc_shell |
In most shrines it is considered a duty of the shrine slaves to have obligatory sex with the priest and sometimes the elders. The priest's genital organs have been dedicated to the gods of the shrine, so having sex with him is considered a sacred act - in a sense, copulating with the gods. This is the origin and meaning of the term "wives of the gods." Many trokosi and vudusi have described beatings and other severe punishments imposed on them for refusing sex with the priest. | https://en.wikipedia.org/wiki/Ritual_servitude |
In Ghana, human rights organizations monitoring the practice of "trokosi" claim that shrine slaves often end up with an average of four children while in servitude, many of them by the priest or elders of the shrines. Proponents of ritual servitude deny that this is a part of the practice. There seem to be wide differences between practices in different districts, but Rouster claims that the problem of forced sex in many of the shrines is too well documented to be disputed. Stephen Awudi Gadri, founder of Trokosi Abolition Fellowship, speaks of "ritual violation after menarche" (first menses) as the beginning of a life of coerced sex. He refers to the trokosi as "vestal virgins." | https://en.wikipedia.org/wiki/Ritual_servitude |
In most silicates, silicon atom occupies the center of an idealized tetrahedron whose corners are four oxygen atoms, connected to it by single covalent bonds according to the octet rule. The oxygen atoms, which bears some negative charge, link to other cations (Mn+). This Si-O-M-O-Si linkage is strong and rigid, which properties are manifested in the rock-like silicates. The silicates can be classified according to the length and crosslinking of the silicate anions. | https://en.wikipedia.org/wiki/Silicon–oxygen_tetrahedron |
In most simple games, the ESSes and Nash equilibria coincide perfectly. For instance, in the prisoner's dilemma there is only one Nash equilibrium, and its strategy (Defect) is also an ESS. Some games may have Nash equilibria that are not ESSes. For example, in harm thy neighbor (whose payoff matrix is shown here) both (A, A) and (B, B) are Nash equilibria, since players cannot do better by switching away from either. | https://en.wikipedia.org/wiki/Evolutionarily_Stable_Strategy |
However, only B is an ESS (and a strong Nash). A is not an ESS, so B can neutrally invade a population of A strategists and predominate, because B scores higher against B than A does against B. This dynamic is captured by Maynard Smith's second condition, since E(A, A) = E(B, A), but it is not the case that E(A,B) > E(B,B). Nash equilibria with equally scoring alternatives can be ESSes. | https://en.wikipedia.org/wiki/Evolutionarily_Stable_Strategy |
For example, in the game Harm everyone, C is an ESS because it satisfies Maynard Smith's second condition. D strategists may temporarily invade a population of C strategists by scoring equally well against C, but they pay a price when they begin to play against each other; C scores better against D than does D. So here although E(C, C) = E(D, C), it is also the case that E(C,D) > E(D,D). As a result, C is an ESS. | https://en.wikipedia.org/wiki/Evolutionarily_Stable_Strategy |
Even if a game has pure strategy Nash equilibria, it might be that none of those pure strategies are ESS. Consider the Game of chicken. There are two pure strategy Nash equilibria in this game (Swerve, Stay) and (Stay, Swerve). | https://en.wikipedia.org/wiki/Evolutionarily_Stable_Strategy |
However, in the absence of an uncorrelated asymmetry, neither Swerve nor Stay are ESSes. There is a third Nash equilibrium, a mixed strategy which is an ESS for this game (see Hawk-dove game and Best response for explanation). This last example points to an important difference between Nash equilibria and ESS. Nash equilibria are defined on strategy sets (a specification of a strategy for each player), while ESS are defined in terms of strategies themselves. The equilibria defined by ESS must always be symmetric, and thus have fewer equilibrium points. | https://en.wikipedia.org/wiki/Evolutionarily_Stable_Strategy |
In most simple metals, like aluminium, the screening effect strongly reduces the electric field of the ions in the solid. The electrostatic potential is expressed as V ( r ) = Z e r e − q r {\displaystyle V(r)={\frac {Ze}{r}}e^{-qr}} where Z is the atomic number, e is the elementary unit charge, r is the distance to the nucleus of the embedded ion and q is a screening parameter that determines the range of the potential. The Fourier transform, U G {\displaystyle U_{\mathbf {G} }} , of the lattice potential, V ( r ) {\displaystyle V(\mathbf {r} )} , is expressed as U G = 4 π Z e q 2 + G 2 {\displaystyle U_{\mathbf {G} }={\frac {4\pi Ze}{q^{2}+G^{2}}}} When the values of the off-diagonal elements U G {\displaystyle U_{\mathbf {G} }} between the reciprocal lattice vectors in the Hamiltonian almost go to zero. As a result, the magnitude of the band gap 2 | U G | {\displaystyle 2|U_{\mathbf {G} }|} collapses and the empty lattice approximation is obtained. | https://en.wikipedia.org/wiki/Empty_lattice_approximation |
In most simulations, periodic boundary conditions are used to avoid imposing artificial boundary conditions. Using cell lists, these boundaries can be implemented in two ways. | https://en.wikipedia.org/wiki/Cell_lists |
In most single-tablet, over-the-counter, daily vitamin and mineral supplements, zinc is included in such forms as zinc oxide, zinc acetate, zinc gluconate, or zinc amino acid chelate.Generally, zinc supplement is recommended where there is high risk of zinc deficiency (such as low and middle income countries) as a preventive measure. Although zinc sulfate is a commonly used zinc form, zinc citrate, gluconate and picolinate may be valid options as well. These forms are better absorbed than zinc oxide. | https://en.wikipedia.org/wiki/Zinc_concentrate |
In most situations it is impractical to achieve escape velocity almost instantly, because of the acceleration implied, and also because if there is an atmosphere, the hypersonic speeds involved (on Earth a speed of 11.2 km/s, or 40,320 km/h) would cause most objects to burn up due to aerodynamic heating or be torn apart by atmospheric drag. For an actual escape orbit, a spacecraft will accelerate steadily out of the atmosphere until it reaches the escape velocity appropriate for its altitude (which will be less than on the surface). In many cases, the spacecraft may be first placed in a parking orbit (e.g. a low Earth orbit at 160–2,000 km) and then accelerated to the escape velocity at that altitude, which will be slightly lower (about 11.0 km/s at a low Earth orbit of 200 km). The required additional change in speed, however, is far less because the spacecraft already has a significant orbital speed (in low Earth orbit speed is approximately 7.8 km/s, or 28,080 km/h). | https://en.wikipedia.org/wiki/Escape_velocity |
The unknown integer a ′ {\displaystyle a'} introduces an ambiguity into the expected value of f ( θ ) {\displaystyle f(\theta )} , similar to the problem of calculating angular mean. This can be resolved by introducing the parameter z = e i θ {\displaystyle z=e^{i\theta }} , since z {\displaystyle z} has an unambiguous relationship to the true angle ϕ {\displaystyle \phi }: z = e i θ = e i ϕ {\displaystyle z=e^{i\theta }=e^{i\phi }} .Calculating the expected value of a function of z {\displaystyle z} will yield unambiguous answers: ⟨ f ( z ) ⟩ = ∫ 0 2 π p w ( θ ′ ) f ( e i θ ′ ) d θ ′ {\displaystyle \langle f(z)\rangle =\int _{0}^{2\pi }p_{w}(\theta ')f(e^{i\theta '})d\theta '} .For this reason, the z {\displaystyle z} parameter is preferred over measured angles θ {\displaystyle \theta } in circular statistical analysis. This suggests that the wrapped distribution function may itself be expressed as a function of z {\displaystyle z} such that: ⟨ f ( z ) ⟩ = ∮ p w z ( z ) f ( z ) d z {\displaystyle \langle f(z)\rangle =\oint p_{wz}(z)f(z)\,dz} where p w ( z ) {\displaystyle p_{w}(z)} is defined such that p w ( θ ) | d θ | = p w z ( z ) | d z | {\displaystyle p_{w}(\theta )\,|d\theta |=p_{wz}(z)\,|dz|} . | https://en.wikipedia.org/wiki/Wrapped_distribution |
This concept can be extended to the multivariate context by an extension of the simple sum to a number of F {\displaystyle F} sums that cover all dimensions in the feature space: p w ( θ → ) = ∑ k 1 , . . . , k F = − ∞ ∞ p ( θ → + 2 π k 1 e 1 + ⋯ + 2 π k F e F ) {\displaystyle p_{w}({\vec {\theta }})=\sum _{k_{1},...,k_{F}=-\infty }^{\infty }{p({\vec {\theta }}+2\pi k_{1}\mathbf {e} _{1}+\dots +2\pi k_{F}\mathbf {e} _{F})}} where e k = ( 0 , … , 0 , 1 , 0 , … , 0 ) T {\displaystyle \mathbf {e} _{k}=(0,\dots ,0,1,0,\dots ,0)^{\mathsf {T}}} is the k {\displaystyle k} th Euclidean basis vector. | https://en.wikipedia.org/wiki/Wrapped_distribution |
In most situations, described above, the increase in ventricular wall thickness is a slow process. However, in some instances hypertrophy may be "dramatic and rapid." In the Burmese python, consumption of a large meal is associated with an increase in metabolic work by a factor of seven and a 40% increase in ventricular mass within 48 hours, both of which return to normal within 28 days. | https://en.wikipedia.org/wiki/Cardiac_hypertrophy |
In most situations, highly specialized species are constrained to a small portion of the accessible environment, characterized by extremely isolated populations. This ecological specialization, and consequently geographical constraint of indigenous populations is frequently accompanied by a reduction in gene flow, resulting in small population sizes and genetic differentiation. As a result, due to genetic isolation, such species can only survive if they are suited to minimal genetic isolation. In the search for lethal genes, genetic isolates with a background of a small founding population, long-term isolation, and population bottlenecks are invaluable resources. | https://en.wikipedia.org/wiki/Genetic_isolate |
Specific rare, monogenic disorders get enhanced, and families with numerous sick members become common enough to be employed in locus-identifying linkage analyses. Besides that, most cases are caused by the same mutation, and diseased alleles expose the linkage of disequilibrium with molecular markers over strong genetic distances, making disease locus recognition easier in small study samples with few individuals affected using a similarity search for a shared genotype. The presence of disequilibrium linkage in disease alleles enhances linkage analysis and aids in determining the precise position of the disease locus on the genome sequence. | https://en.wikipedia.org/wiki/Genetic_isolate |
In most situations, relativistic effects can be neglected, and Newton's laws give a sufficiently accurate description of motion. The acceleration of a body is equal to the sum of the forces acting on it, divided by its mass, and the gravitational force acting on a body is proportional to the product of the masses of the two attracting bodies and decreases inversely with the square of the distance between them. To this Newtonian approximation, for a system of two-point masses or spherical bodies, only influenced by their mutual gravitation (called a two-body problem), their trajectories can be exactly calculated. If the heavier body is much more massive than the smaller, as in the case of a satellite or small moon orbiting a planet or for the Earth orbiting the Sun, it is accurate enough and convenient to describe the motion in terms of a coordinate system that is centered on the heavier body, and we say that the lighter body is in orbit around the heavier. For the case where the masses of two bodies are comparable, an exact Newtonian solution is still sufficient and can be had by placing the coordinate system at the center of the mass of the system. | https://en.wikipedia.org/wiki/Orbital_data |
In most situations, such as those with nonzero variable costs, revenue-maximizing prices are not profit-maximizing prices. For these situations, using a technique for Profit maximization is more appropriate. | https://en.wikipedia.org/wiki/Demand_elasticity |
In most situations, the user does not want to just capture an arbitrary time that an event occurs, but wants to measure a time interval, the time between a start event and a stop event. That can be done by measuring an arbitrary time of both the start and stop events and subtracting. The measurement can be off by two counts. The subtraction can be avoided if the counter is held at zero until the start event, counts during the interval, and then stops counting after the stop event. | https://en.wikipedia.org/wiki/Time_to_digital_converter |
Coarse counters base on a reference clock with signals generated at a stable frequency f 0 {\displaystyle f_{0}} . When the start signal is detected the counter starts counting clock signals and terminates counting after the stop signal is detected. The time interval T {\displaystyle T} between start and stop is then T = n ⋅ T 0 {\displaystyle T=n\cdot T_{0}} with n {\displaystyle n} , the number of counts and T 0 = 1 / f 0 {\displaystyle T_{0}=1/f_{0}} , the period of the reference clock. | https://en.wikipedia.org/wiki/Time_to_digital_converter |
In most ski resorts, the runs are graded according to comparative difficulty so that skiers can select appropriate routes. The grading schemes around the world are related, although with significant regional variations. A beginner-rated trail at a large mountain may be more of an intermediate-rated trail on a smaller mountain. In the United States and Canada, there are four rating symbols: Easy (green circle), Intermediate (blue square), and Difficult (black diamond), and Experts Only (double black diamond) Ski trail difficulty is measured by percent slope, not degree angle. | https://en.wikipedia.org/wiki/Downhill_skiing |
A 100% slope is a 45-degree angle. In general, beginner slopes (green circle) are between 6% and 25%. Intermediate slopes (blue square) are between 25% and 40%. | https://en.wikipedia.org/wiki/Downhill_skiing |
Difficult slopes (black diamond) are 40% and up. Although slope gradient is the primary consideration in assigning a trail difficulty rating, other factors come into play. A trail will be rated by its most difficult part, even if the rest of the trail is easy. Ski resorts assign ratings to their own trails, rating a trail compared only with other trails at that resort. Also considered are width of the trail, sharpest turns, terrain roughness, and whether the resort regularly grooms the trail. | https://en.wikipedia.org/wiki/Downhill_skiing |
In most snakes, teeth are located on the dentary of the lower jaw, the maxilla, the palatine bone and the lateral pterygoid plate. The latter form an "inner row" of teeth that can move separately from the rest of the jaws and are used to help "walk" the jaws over prey. Several snake lineages have evolved venom which is typically delivered by specialized teeth called fangs located on the maxilla. Most snakes can be placed into one of four groups, based on their teeth, which correlate strongly with venom and lineage. | https://en.wikipedia.org/wiki/Snake_skull |
In most societies, numbers of men and women are roughly equal. Though women are not considered to be a minority, the status of women, as a subordinate group, has led to many social scientists to study them as a disadvantaged group. Though women's legal rights and status vary widely across countries, women can experience social inequalities, relative to men, in various societies. Women are sometimes denied access to education and access to the same opportunities as men. | https://en.wikipedia.org/wiki/Minority_group |
In most societies, the death of one of the partners terminates the marriage, and in monogamous societies, this allows the other partner to remarry, though sometimes after a waiting or mourning period. In some societies, a marriage can be annulled, when an authority declares that a marriage never happened. Jurisdictions often have provisions for void marriages or voidable marriages. | https://en.wikipedia.org/wiki/Temporary_marriage |
A marriage may also be terminated through divorce. Countries that have relatively recently legalized divorce are Italy (1970), Portugal (1975), Brazil (1977), Spain (1981), Argentina (1987), Paraguay (1991), Colombia (1991), Ireland (1996), Chile (2004) and Malta (2011). As of 2012, the Philippines and the Vatican City are the only jurisdictions which do not allow divorce (this is currently under discussion in Philippines). | https://en.wikipedia.org/wiki/Temporary_marriage |
After divorce, one spouse may have to pay alimony. Laws concerning divorce and the ease with which a divorce can be obtained vary widely around the world. After a divorce or an annulment, the people concerned are free to remarry (or marry). | https://en.wikipedia.org/wiki/Temporary_marriage |
A statutory right of two married partners to mutually consent to divorce was enacted in western nations in the mid-20th century. In the United States, no-fault divorce was first enacted in California in 1969 and the final state to legalize it was New York in 1989.About 45% of marriages in Britain and, according to a 2009 study, 46% of marriages in the U.S. end in divorce. | https://en.wikipedia.org/wiki/Temporary_marriage |
In most solids (but not all), the molecules have a fixed mean position and orientation, and therefore the only degrees of freedom available are the vibrations of the atoms. Thus the specific heat is proportional to the number of atoms (not molecules) per unit of mass, which is the Dulong–Petit law. Other contributions may come from magnetic degrees of freedom in solids, but these rarely make substantial contributions. and electronic Since each atom of the solid contributes one independent vibration mode, the number of degrees of freedom in n atoms is 6n. | https://en.wikipedia.org/wiki/Molar_heat_capacity |
Therefore, the heat capacity of a sample of a solid substance is expected to be 3RNa, or (24.94 J/K)Na, where Na is the number of moles of atoms in the sample, not molecules. Said another way, the atom-molar heat capacity of a solid substance is expected to be 3R = 24.94 J⋅K−1⋅mol−1, where "amol" denotes an amount of the solid that contains the Avogadro number of atoms.It follows that, in molecular solids, the heat capacity per mole of molecules will usually be close to 3nR, where n is the number of atoms per molecule. Thus n atoms of a solid should in principle store twice as much energy as n atoms of a monatomic gas. | https://en.wikipedia.org/wiki/Molar_heat_capacity |
One way to look at this result is to observe that the monatomic gas can only store energy as kinetic energy of the atoms, whereas the solid can store it also as potential energy of the bonds strained by the vibrations. The atom-molar heat capacity of a polyatomic gas approaches that of a solid as the number n of atoms per molecule increases. As in the case f gases, some of the vibration modes will be "frozen out" at low temperatures, especially in solids with light and tightly bound atoms, causing the atom-molar heat capacity to be less than this theoretical limit. Indeed, the atom-molar (or specific) heat capacity of a solid substance tends toward zero, as the temperature approaches absolute zero. | https://en.wikipedia.org/wiki/Molar_heat_capacity |
In most solids, ions rigidly occupy fixed positions, strongly embraced by neighboring atoms or ions. In some solids, selected ions are highly mobile allowing ionic conduction. The mobility increases with temperature. Materials exhibiting this property are used in batteries. | https://en.wikipedia.org/wiki/Ion_conductivity |
A well-known ion conductive solid is β''-alumina ("BASE"), a form of aluminium oxide that has channels through which sodium cations can hop. When this ceramic is complexed with a mobile ion, such as Na+, it behaves as so-called fast ion conductor. BASE is used as a membrane in several types of molten salt electrochemical cell. | https://en.wikipedia.org/wiki/Ion_conductivity |
In most species, adult females lay their eggs in stagnant water: some lay near the water's edge while others attach their eggs to aquatic plants. Each species selects the situation of the water into which it lays its eggs and does so according to its own ecological adaptations. Some breed in lakes, some in temporary puddles. Some breed in marshes, some in salt-marshes. | https://en.wikipedia.org/wiki/Mosquito_larva |
Among those that breed in salt water (such as Opifex fuscus), some are equally at home in fresh and salt water up to about one-third the concentration of seawater, whereas others must acclimatize themselves to the salinity. Such differences are important because certain ecological preferences keep mosquitoes away from most humans, whereas other preferences bring them into houses at night. Some species of mosquitoes prefer to breed in phytotelmata (natural reservoirs on plants), such as rainwater accumulated in holes in tree trunks, or in the leaf-axils of bromeliads. | https://en.wikipedia.org/wiki/Mosquito_larva |
Some specialize in the liquid in pitchers of particular species of pitcher plants, their larvae feeding on decaying insects that had drowned there or on the associated bacteria; the genus Wyeomyia provides such examples—the harmless Wyeomyia smithii breeds only in the pitchers of Sarracenia purpurea.Some of the species of mosquitoes that are adapted to breeding in phytotelmata are dangerous disease vectors. In nature, they might occupy anything from a hollow tree trunk to a cupped leaf. Such species typically take readily to breeding in artificial water containers. | https://en.wikipedia.org/wiki/Mosquito_larva |
Such casual puddles are important breeding places for some of the most serious disease vectors, such as species of Aedes that transmit dengue and yellow fever. Some with such breeding habits are disproportionately important vectors because they are well-placed to pick up pathogens from humans and pass them on. In contrast, no matter how voracious, mosquitoes that breed and feed mainly in remote wetlands and salt marshes may well remain uninfected, and if they do happen to become infected with a relevant pathogen, might seldom encounter humans to infect, in turn. | https://en.wikipedia.org/wiki/Mosquito_larva |
In most species, the principal eyes are more visually acute than the secondary eyes, at the cost of their sensitivity. They lack a tapetum entirely, and the retina is everted, meaning the rhabdomeres (light-sensitive parts of the visual cells) point towards the incoming light. Some species can move the retina using between one and six muscles, greatly increasing the field of view. No actual focusing takes place; it is unnecessary, since the small lenses and short focal length of most spiders' principal eyes lead to a wide depth of field. When a spider has colour vision, it is typically the principal eyes which are responsible. | https://en.wikipedia.org/wiki/Spider_vision |
In most species, the sex ratio varies according to the age profile of the population.It is generally divided into four subdivisions: primary sex ratio — ratio at fertilization secondary sex ratio — ratio at birth tertiary sex ratio — ratio in sexually mature organismsThis is equivalent to the adult sex ratio (ASR), which is defined as the ratio of adult males to females in a population.The operational sex ratio (OSR) is the ratio of sexually active males to females in a population, and is therefore derived from a subset of the individuals included when calculating the ASR. Although conceptually distinct, researchers have sometimes equated the ASR with the OSR, particularly in experimental studies of animals where the difference between the two values may not always be readily apparent.quaternary sex ratio — ratio in post-reproductive organismsThese definitions can be somewhat subjective since they lack clear boundaries. | https://en.wikipedia.org/wiki/Gender_balance |
In most species, the stomach itself is a relatively simple sac, and is the main site of digestion. In many herbivores, however, the hind part of the oesophagus is enlarged to form a crop, which, in terrestrial pulmonates, may even replace the stomach entirely. In many aquatic herbivores, however, the stomach is adapted into a gizzard that helps to grind up the food. The gizzard may have a tough cuticle, or may be filled with abrasive sand grains.In the most primitive gastropods, however, the stomach is a more complex structure. | https://en.wikipedia.org/wiki/Digestive_system_of_gastropods |
In these species, the hind part of the stomach, where the oesophagus enters, is chitinous, and includes a sorting region lined with cilia.In all gastropods, the portion of the stomach furthest from the oesophagus, called the "style sac", is lined with cilia. These beat in a rotary motion, pulling the food forward in a steady stream from the mouth. Usually, the food is embedded in a string of mucus produced in the mouth, creating a coiled conical mass in the style sac. This action, rather than muscular peristalsis, is responsible for the movement of food through the gastropod digestive tract.Two diverticular glands open into the stomach, and secrete enzymes that help to break down the food. In the more primitive species, these glands may also absorb the food particles directly and digest them intracellularly. | https://en.wikipedia.org/wiki/Digestive_system_of_gastropods |
In most species, the young organism that is just born or hatched is not sexually mature yet and in most animals, this young organism looks quite different than the adult form. This young organism is the larva and is the intermediate form before metamorphosing into an adult. A well known example of a larval form of an animal is the caterpillar of butterflies and moths. | https://en.wikipedia.org/wiki/Ontogenetic_stage |
Caterpillars keep growing and feeding in order for enough energy during the pupal stage, when necessary body parts for metamorphosis are grown. The juvenile phase is different in plants and animals, but in plants juvenility is an early phase of plant growth in which plants can't flower. In animals, the juvenile stage is most commonly found in social mammals, such as wild dogs, monkeys, apes, lions, wolves, and more. | https://en.wikipedia.org/wiki/Ontogenetic_stage |
In humans, puberty marks the end of this stage and adolescence follows. Some species begin puberty and reproduction before the juvenile stage is over, such as in female non-human primates. The larval and pupal stages can be seen in the figure to the right. | https://en.wikipedia.org/wiki/Ontogenetic_stage |
In most stability studies, real-time or accelerated, a few units of the reference material are tested at intervals. If the measurement system used for testing the materials is not perfectly stable, this can generate imprecise data or can be mistaken for instability of the material. To overcome these difficulties, it is often possible to move RM units, at intervals, to some reference temperature where they remain stable, and then test all the accumulated units - which have undergone different exposure times - at the same time. This is referred to as an isochronous study. This strategy has the advantage of improving the precision of data used in assessing stability at the cost of delaying results until the end of the stability study period. | https://en.wikipedia.org/wiki/Certified_reference_materials |
In most standard Wi-Fi routers, the three standards, a, b and g, are enough. But in long-range Wi-Fi, special technologies are used to get the most out of a Wi-Fi connection. The 802.11-2007 standard adds 10 MHz and 5 MHz OFDM modes to the 802.11a standard, and extend the time of cyclic prefix protection from 0.8 μs to 3.2 μs, quadrupling the multipath distortion protection. Some commonly available 802.11a/g chipsets support the OFDM 'half-clocking' and 'quarter-clocking' that is in the 2007 standard, and 4.9 GHz and 5.0 GHz products are available with 10 MHz and 5 MHz channel bandwidths. It is likely that some 802.11n D.20 chipsets will also support 'half-clocking' for use in 10 MHz channel bandwidths, and at double the range of the 802.11n standard. | https://en.wikipedia.org/wiki/Long-range_Wi-Fi |
In most states (excluding Texas and Hawaii), a state education agency credentials school psychologists for practice in the schools.The Nationally Certified School Psychologist (NCSP) credential is offered by the National Association of School Psychologists (NASP). The NCSP credential is an example of a non-practice credential as holding the NCSP does not make one eligible to provide services without first meeting the state requirements to work as a school psychologist. State psychology boards (which may go by different names in each state) also offer credentials for school psychologists in some states. For example, Texas offers the LSSP credential which permits licensees to deliver school psychological services within public and private schools. | https://en.wikipedia.org/wiki/School_psychology |
In most states in the US, a judicial order following a formal hearing is needed before a patient can be forced to undergo involuntary ECT. However, ECT can also be involuntarily administered in situations with less immediate danger. Suicidal intent is a common justification for its involuntary use, especially when other treatments are ineffective. | https://en.wikipedia.org/wiki/Electroshock_therapy |
In most states there is no requirement to disclose the commission of the broker to the customer, but in New York, a regulation ("Regulation 194") was adopted in 2011 which required disclosure. Brokers or agents may decide to reveal their commission upon request.In most states, agents cannot charge a fee in addition to their commission, although Texas is one of the exceptions. | https://en.wikipedia.org/wiki/Insurance_broker |
In most states, insurance coverage for IVF is not mandated and varies by state. Insurance providers do not typically cover the costs of reciprocal IVF unless it is medically necessary. Only 25% of Americans have coverage for IVF. On average, the cost of one IVF cycle costs about $12,000, which does not include fertility medications that typically range from $3,000 to $10,000. The average cost of reciprocal IVF in the United States is over $20,000 but varies based on the clinic and medication protocols.The cost of reciprocal IVF is more than IVF due to additional costs including donor sperm fees, legal fees, and fertility medications. | https://en.wikipedia.org/wiki/Reciprocal_IVF |
In most statistical studies, the goal is to generalize from the observed units to a larger set consisting of all comparable units that exist but are not directly observed. For example, if we randomly sample 100 people and ask them which candidate they intend to vote for in an election, our main interest is in the voting behavior of all eligible voters, not exclusively on the 100 observed units. In some cases, the observed units may not form a sample from any meaningful population, but rather constitute a convenience sample, or may represent the entire population of interest. In this situation, we may study the units descriptively, or we may study their dynamics over time. | https://en.wikipedia.org/wiki/Statistical_unit |
But it typically does not make sense to talk about generalizing to a larger population of such units. Studies involving countries or business firms are often of this type. Clinical trials also typically use convenience samples, however the aim is often to make inferences about the effectiveness of treatments in other patients, and given the inclusion and exclusion criteria for some clinical trials, the sample may not be representative of the majority of patients with the condition or disease. | https://en.wikipedia.org/wiki/Statistical_unit |
In simple data sets, the units are in one-to-one correspondence with the data values. In more complex data sets, multiple measurements are made for each unit. For example, if blood pressure measurements are made daily for a week on each subject in a study, there would be seven data values for each statistical unit. | https://en.wikipedia.org/wiki/Statistical_unit |
Multiple measurements taken on an individual are not independent (they will be more alike compared to measurements taken on different individuals). Ignoring these dependencies during the analysis can lead to an inflated sample size or pseudoreplication. | https://en.wikipedia.org/wiki/Statistical_unit |
While a unit is often the lowest level at which observations are made, in some cases, a unit can be further decomposed as a statistical assembly. Many statistical analyses use quantitative data that have units of measurement. This is a distinct and non-overlapping use of the term "unit." | https://en.wikipedia.org/wiki/Statistical_unit |
In most stratified lakes, seasonal changes in the spring and fall air temperature cause the epilimnion to warm up or cool down. During these seasonal changes stratified lakes may experience a lake turnover. During this, the epilimnion and hypolimnion mix together and the lake generally becomes un-stratified, meaning it has a constant temperature throughout, and the nutrients are even throughout the lake. | https://en.wikipedia.org/wiki/Epilimnion |
There are different names for these turnovers based on how many times the lake does it in a year. Monomictic lakes flip only once, dimictic flip twice, and polymictic lakes flip more than twice. These turnovers can be based on seasonal differences, or can even happen daily. In some cases this causes the lake to have inverse stratification, where the epilimnion has cooler water than the hypolimnion. | https://en.wikipedia.org/wiki/Epilimnion |
In most studies, a majority of cell phone users report experiencing occasional phantom vibrations or ringing, with reported rates ranging from 29.6% to 89%. Once every two weeks is a typical frequency for the sensations, though a minority experience them daily. Some individuals may be seriously bothered by the sensations. | https://en.wikipedia.org/wiki/Phantom_rings |
In most successful combined cycles, the bottoming cycle for power is a conventional steam Rankine cycle. It is already common in cold climates (such as Finland) to drive community heating systems from a steam power plant's condenser heat. Such cogeneration systems can yield theoretical efficiencies above 95%. | https://en.wikipedia.org/wiki/Integrated_solar_combined_cycle |
Bottoming cycles producing electricity from the steam condenser's heat exhaust are theoretically possible, but conventional turbines are uneconomically large. The small temperature differences between condensing steam and outside air or water require very large movements of mass to drive the turbines. Although not reduced to practice, a vortex of air can concentrate the mass flows for a bottoming cycle. Theoretical studies of the Vortex engine show that if built at scale it is an economical bottoming cycle for a large steam Rankine cycle power plant. | https://en.wikipedia.org/wiki/Integrated_solar_combined_cycle |
In most surface ecosystems, photosynthetic plants and microbes are the main primary producers that form the base of the lake food web. Photosynthesis is impossible in the permanent darkness of subglacial lakes, so these food webs are instead driven by chemosynthesis. In subglacial ecosystems, chemosynthesis is mainly carried out by chemolithoautotrophic microbes.Like plants, chemolithoautotrophs fix carbon dioxide (CO2) into new organic carbon, making them the primary producers at the base of subglacial lake food webs. Rather than using sunlight as an energy source, chemolithoautotrophs get energy from chemical reactions in which inorganic elements from the lithosphere are oxidized or reduced . | https://en.wikipedia.org/wiki/Subglacial_lake |
Common elements used by chemolithoautotrophs in subglacial ecosystems include sulfide, iron, and carbonates weathered from sediments.In addition to mobilizing elements from sediments, chemolithoautotrophs create enough new organic matter to support heterotrophic bacteria in subglacial ecosystems. Heterotrophic bacteria consume the organic material produced by chemolithoautotrophs, as well as consuming organic matter from sediments or from melting glacial ice. Despite the resources available to subglacial lake heterotrophs, these bacteria appear to be exceptionally slow-growing, potentially indicating that they dedicate most of their energy to survival rather than growth. | https://en.wikipedia.org/wiki/Subglacial_lake |
Slow heterotrophic growth rates could also be explained by the cold temperatures in subglacial lakes, which slow down microbial metabolism and reaction rates.The variable redox conditions and diverse elements available from sediments provide opportunities for many other metabolic strategies in subglacial lakes. Other metabolisms used by subglacial lake microbes include methanogenesis, methanotrophy, and chemolithoheterotrophy, in which bacteria consume organic matter while oxidizing inorganic elements.Some limited evidence for microbial eukaryotes and multicellular animals in subglacial lakes could expand current ideas of subglacial food webs. If present, these organisms could survive by consuming bacteria and other microbes. | https://en.wikipedia.org/wiki/Subglacial_lake |
In most suspected cases, DVT is ruled out after evaluation. Cellulitis is a frequent mimic of DVT, with its triad of pain, swelling, and redness. Symptoms concerning for DVT are more often due to other causes, including cellulitis, ruptured Baker's cyst, hematoma, lymphedema, and chronic venous insufficiency. Other differential diagnoses include tumors, venous or arterial aneurysms, connective tissue disorders, superficial vein thrombosis, muscle vein thrombosis, and varicose veins. | https://en.wikipedia.org/wiki/Deep_vein_thrombosis |
In most systems a stack frame has a field to contain the previous value of the frame pointer register, the value it had while the caller was executing. For example, the stack frame of DrawLine would have a memory location holding the frame pointer value that DrawSquare uses (not shown in the diagram above). The value is saved upon entry to the subroutine. Having such a field in a known location in the stack frame enables code to access each frame successively underneath the currently executing routine's frame, and also allows the routine to easily restore the frame pointer to the caller's frame, just before it returns. | https://en.wikipedia.org/wiki/Run-time_stack |
In most systems of national accounts the GDP deflator measures the ratio of nominal (or current-price) GDP to the real (or chain volume) measure of GDP. The formula used to calculate the deflator is: G D P d e f l a t o r = N o m i n a l G D P R e a l G D P × 100 {\displaystyle \operatorname {GDP\ deflator} ={\frac {\operatorname {Nominal\ GDP} }{\operatorname {Real\ GDP} }}\times 100} The nominal GDP of a given year is computed using that year's prices, while the real GDP of that year is computed using the base year's prices. The formula implies that dividing the nominal GDP by the real GDP and multiplying it by 100 will give the GDP Deflator, hence "deflating" the nominal GDP into a real measure.It is often useful to consider implicit price deflators for certain subcategories of GDP, such as computer hardware. In this case, it is useful to think of the price deflator as the ratio of the current-year price of a good to its price in some base year. | https://en.wikipedia.org/wiki/Gross_Domestic_Product_deflator |
The price in the base year is normalized to 100. For example, for computer hardware, we could define a "unit" to be a computer with a specific level of processing power, memory, hard drive space and so on. A price deflator of 200 means that the current-year price of this computing power is twice its base-year price - price inflation. | https://en.wikipedia.org/wiki/Gross_Domestic_Product_deflator |
A price deflator of 50 means that the current-year price is half the base year price - price deflation. This can lead to a situation where official statistics reflect a drop in real prices, even though they nominally have stayed the same. | https://en.wikipedia.org/wiki/Gross_Domestic_Product_deflator |
Unlike some price indices (like the CPI), the GDP deflator is not based on a fixed basket of goods and services. The basket is allowed to change with people's consumption and investment patterns. Specifically, for the GDP deflator, the "basket" in each year is the set of all goods that were produced domestically, weighted by the market value of the total consumption of each good. | https://en.wikipedia.org/wiki/Gross_Domestic_Product_deflator |
Therefore, new expenditure patterns are allowed to show up in the deflator as people respond to changing prices. The theory behind this approach is that the GDP deflator reflects up to date expenditure patterns. | https://en.wikipedia.org/wiki/Gross_Domestic_Product_deflator |
For instance, if the price of chicken increases relative to the price of beef, people may spend more money on beef as a substitute for chicken. In practice, the difference between the deflator and a price index like the Consumer price index (CPI) is often relatively small. On the other hand, with governments in developed countries increasingly utilizing price indexes for everything from fiscal and monetary planning to payments to social program recipients, even small differences between inflation measures can shift budget revenues and expenses by millions or billions of dollars. | https://en.wikipedia.org/wiki/Gross_Domestic_Product_deflator |
In most systems, a trademark can be registered if it can distinguish the goods or services of a party, will not confuse consumers about the relationship between one party and another, and will not otherwise deceive consumers concerning the qualities. | https://en.wikipedia.org/wiki/Registered_trademark |
In most systems, bonding between a ligand and a metal atom can be thought of in terms of metal-ligand covalent bonds, where the occupied ligand orbitals donate some electron density to the metal. This is commonly known as ligand-to-metal charge transfer or LMCT. In some cases, low-lying unoccupied ligand orbitals (π*) can receive back-donation (or backbonding) from the occupied metal orbitals. | https://en.wikipedia.org/wiki/Metal_L-edge |
This has the opposite effect on the system, resulting in metal-to-ligand charge transfer, MLCT, and commonly appears as an additional L-edge spectral feature. An example of this feature occurs in low-spin ferric 3−, since CN− is a ligand that can have backbonding. While backbonding is important in the initial state, it would only warrant a small feature in the L-edge spectrum. In fact, it is in the final state where the backbonding π* orbitals are allowed to mix with the very intense eg transition, thus borrowing intensity and resulting in the final dramatic three peak spectrum (Figure 3 and Figure 4). | https://en.wikipedia.org/wiki/Metal_L-edge |
In most systems, metal probes (electrodes) are inserted into the ground to obtain a reading of the local electrical resistance. A variety of probe configurations are used, most having four probes, often mounted on a rigid frame. In these systems, two of the probes, called current probes, are used to introduce a current (either direct or low-frequency switching current) into the earth. The other two probes, called voltage or potential probes, are used to measure the voltage, which indicates the local resistivity. | https://en.wikipedia.org/wiki/Electrical_resistance_survey |
In general, greater probe spacings yield greater depth of investigation, but at the cost of sensitivity and spatial resolution.Early surveys (beginning in the mid 20th century) often used the Wenner array, which was a linear array of four probes. These were arranged current-voltage-voltage-current, at equal distances across the array. Probes were mounted on a rigid frame, or placed individually. | https://en.wikipedia.org/wiki/Electrical_resistance_survey |
While quite sensitive, this array has a very wide span for its depth of investigation, leading to problems with horizontal resolution. A number of experimental arrays attempted to overcome the shortcomings of the Wenner array, the most successful of these being the twin-probe array, which has become the standard for archaeological use. The twin-probe array - despite its name - has four probes: one current and one voltage probe mounted on a mobile frame to collect survey readings, and the other current probe placed remotely along with a voltage reference probe. | https://en.wikipedia.org/wiki/Electrical_resistance_survey |
These fixed remote probes are connected to the mobile survey probes by a trailing cable. This configuration is very compact for its depth of investigation, resulting in superior horizontal resolution. The logistical advantage of the more compact array is somewhat offset by the trailing cable. | https://en.wikipedia.org/wiki/Electrical_resistance_survey |
A disadvantage of the systems described above is a relatively slow rate of survey. One solution to this has been wheeled arrays. | https://en.wikipedia.org/wiki/Electrical_resistance_survey |
These use spiked wheels or metal disks as electrodes, and may use a square array (a variation of the Wenner array) to avoid the encumbrance of a trailing cable. Wheeled arrays may be towed by vehicles or by human power.Systems having long linear arrays of many electrodes are often used in geological applications, and less commonly in archaeology. These take repeated measurements (often computer controlled) using different electrode spacings at multiple points along the extended line of electrodes. | https://en.wikipedia.org/wiki/Electrical_resistance_survey |
Data collected in this way may be used for tomography, or generating vertical profiles.Capacitively coupled systems that do not require direct physical contact with the soil have also been developed. These systems are capable of tomographic studies as well as mapping horizontal patterning. They may also be used on hard or very dry surfaces that preclude electrical contact necessary for probe resistance systems. While these show promise for archaeological applications, currently available systems operating on this principle lack sufficient spatial resolution and sensitivity. | https://en.wikipedia.org/wiki/Electrical_resistance_survey |
In most systems, the governing body responsible for overseeing the courts assigns a unique number/letter combination or similar designation to each case in order to track the various disputes that are or have been before it. The outcome of the case is recorded, and can later be reviewed by obtaining a copy of the documents associated with the designation previously assigned to the case. However, it is often more convenient to refer to cases – particularly landmark and other notable cases – by a title of the form Claimant v Defendant (e.g. Arkell v Pressdram). Where a legal proceeding does not have formally designated adverse parties, a form such as In re, Re or In the matter of is used (e.g. In re Gault). | https://en.wikipedia.org/wiki/Legal_dispute |
The "v" separating the parties is an abbreviation of the Latin versus, but, when spoken in Commonwealth countries, it is normally rendered as "and" or "against" (as in, for example, Charles Dickens' Jarndyce and Jarndyce). Where it is considered necessary to protect the anonymity of a natural person, some cases may have one or both parties replaced by a standard pseudonym (Jane Roe in Roe v. Wade) or by an initial (D v D). In titles such as R v Adams, however, the initial "R" is usually an abbreviation for the Latin Rex or Regina, i.e. for the Crown. (For an explanation of other terms that may appear in case titles, see the Glossary of legal terms.) | https://en.wikipedia.org/wiki/Legal_dispute |
In most systems, the size of a process's virtual address space is much larger than the available main memory. For example: The address bus that connects the CPU to main memory may be limited. The i386SX CPU's 32-bit internal addresses can address 4 GB, but it has only 24 pins connected to the address bus, limiting installed physical memory to 16 MB. There may be other hardware restrictions on the maximum amount of RAM that can be installed. The maximum memory might not be installed because of cost, because the model's standard configuration omits it, or because the buyer did not believe it would be advantageous. Sometimes not all internal addresses can be used for memory anyway, because the hardware architecture may reserve large regions for I/O or other features. | https://en.wikipedia.org/wiki/Swap_partition |
In most tabletop role-playing games, die rolls required by the system are given in the form AdX. A and X are variables, separated by the letter d, which stands for die or dice. The letter d is most commonly lower-case, but some forms of notation use upper-case D (non-English texts can use the equivalent form of the first letter of the given language's word for "dice", but also often use the English "d"). A is the number of dice to be rolled (usually omitted if 1). | https://en.wikipedia.org/wiki/Percentile_dice |
X is the number of faces of each dice.For example, if a game calls for a roll of d4 or 1d4, it means "roll one 4-sided die." If the final number is omitted, it is typically assumed to be a six, but in some contexts, other defaults are used. 3d6 would mean "roll three six-sided dice." | https://en.wikipedia.org/wiki/Percentile_dice |
Commonly, these dice are added together, but some systems could direct the player use them in some other way, such as choosing the best die rolled. To this basic notation, an additive modifier can be appended, yielding expressions of the form AdX+B. The plus sign is sometimes replaced by a minus sign ("−") to indicate subtraction. | https://en.wikipedia.org/wiki/Percentile_dice |
B is a number to be added to the sum of the rolls. So, 1d20−10 would indicate a roll of a single 20-sided die with 10 being subtracted from the result. These expressions can also be chained (e.g. 2d6+1d8), though this usage is less common. | https://en.wikipedia.org/wiki/Percentile_dice |
Additionally, notation such as AdX−L is not uncommon, the L (or H, less commonly) being used to represent "the lowest result" (or "the highest result"). For instance, 4d6−L means a roll of 4 six-sided dice, dropping the lowest result. This application skews the probability curve towards the higher numbers, as a result a roll of 3 can only occur when all four dice come up 1 (probability 1/1,296), while a roll of 18 results if any three dice are 6 (probability 21/1,296 = 7/432). Rolling three or more dice gives a probability distribution that is approximately Gaussian, in accordance with the central limit theorem. | https://en.wikipedia.org/wiki/Percentile_dice |
In most team sports, the home or hosting team is considered to have a significant advantage over the away or visiting team. Due to this, many important games (such as playoff or elimination matches) in many sports have special rules for determining what match is played where. In association football, matches with two legs, one game played in each team's "home", are common. It is also common to hold important games, such as the Super Bowl, at a neutral site in which the location is determined years in advance. | https://en.wikipedia.org/wiki/Home_advantage |
In many team sports in North America (including baseball, basketball, and ice hockey), playoff series are often held with a nearly equal number of games at each team's site. However, as it is usually beneficial to have an odd number of matches in a series (to prevent ties), the final home game is often awarded to the team that had more success over the regular season. An example is UEFA Champions League and UEFA Europa League home and away legs, with weaker teams often beating the favourites when playing at home. | https://en.wikipedia.org/wiki/Home_advantage |
The World Cup victories of Uruguay (1930), Italy (1934), England (1966), Germany (1974), Argentina (1978) and France (1998) are all in part attributed to the fact that the World Cup was held in the winner's country. A 2006 study by The Times found that in the English Premiership, a home team can be expected to score 37.29% more goals than the away team, though this changes depending on the quality of the teams involved. Others have suggested that the increase in British medals during the 2012 Olympics may have been impacted by home court advantage. | https://en.wikipedia.org/wiki/Home_advantage |
(However, having home court did not help Canada at the 1976 Montreal Olympics, the only Summer Games at which the hosting country failed to win a single gold medal.) The strength of the home advantage varies for different sports, regions, seasons, and divisions. | https://en.wikipedia.org/wiki/Home_advantage |
For all sports, it seems to be strongest in the early period after the creation of a new league. The effect seems to have become somewhat weaker in some sports in recent decades.Adams & Kupper (1994) described home-field advantage as an expertise deficiency. They demonstrated that, in theory and in practice, home-field advantage decreases as superiority of performance increases. | https://en.wikipedia.org/wiki/Home_advantage |
They also showed that home-field advantage is not applicable for no-hit major league baseball games for pitchers who either replicated performance by winning two or more no-hitters or amassed a large number of career wins. Their general finding was that home-field advantage is a metric for the inability to maintain performance independent of environment and that this metric is inversely related to variables of expertise.In recognition of the difficulty in winning away matches, cup competitions in association football often invoke the away goals rule. Away goals can also sometimes be used to separate teams level on points and goal difference in league competitions. | https://en.wikipedia.org/wiki/Home_advantage |
In most team-based esports, organized play is centered around the use of promotion and relegation to move sponsored teams between leagues within the competition's organization based on how the team fared in matches; this follows patterns of professional sports in European and Asian countries. Teams will play a number of games across a season as to vie for top positioning in the league by the end of that season. Those that do well, in addition to prize money, may be promoted into a higher-level league, while those that fare poorly can be regulated downward. | https://en.wikipedia.org/wiki/Electronic_sports |
For example, until 2018 Riot Games runs several League of Legends series, with the League of Legends Championship Series being the top-tier series. Teams that did not do well were relegated to the League of Legends Challenger Series, replaced by the better performing teams from that series. This format was discontinued when Riot opted to use the franchise format in mid-2018. | https://en.wikipedia.org/wiki/Electronic_sports |
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