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Such procedures are often implemented in various convenience routines such as daemon(3) in Unix. Systems often start daemons at boot time that will respond to network requests, hardware activity, or other programs by performing some task. Daemons such as cron may also perform defined tasks at scheduled times. | https://en.wikipedia.org/wiki/Operating_system_service_management |
In multitasking computing an operating system can handle several programs, both native applications or emulated software, that are running independent, parallel, together in the same time in the same device, using separated or shared resources and/or data, executing their tasks separately or together, while a user can switch on the fly between them or groups of them to use obtained effects or supervise purposes, without waste of time or waste of performance. In operating systems using GUI very often it is done by switching from an active window (or an object playing similar role) of a particular software piece to another one but of another software. A computer can compute results on the fly, or retrieve a previously stored result. | https://en.wikipedia.org/wiki/On_the_fly |
It can mean to make a copy of a removable media (CD-ROM, DVD, etc.) directly, without first saving the source on an intermediate medium (a harddisk); for example, copying a CD-ROM from a CD-ROM drive to a CD-Writer drive. The copy process requires each block of data to be retrieved and immediately written to the destination, so that there is room in the working memory to retrieve the next block of data.When used for encrypted data storage, on the fly the data stream is automatically encrypted as it is written and decrypted when read back again, transparently to software. The acronym OTFE is typically used. On-the-fly programming is the technique of modifying a program without stopping it.A similar concept, hot swapping, refers to on-the-fly replacement of computer hardware. | https://en.wikipedia.org/wiki/On_the_fly |
In multitasking operating systems, processes (running programs) need a way to create new processes, e.g. to run other programs. Fork and its variants are typically the only way of doing so in Unix-like systems. For a process to start the execution of a different program, it first forks to create a copy of itself. Then, the copy, called the "child process", calls the exec system call to overlay itself with the other program: it ceases execution of its former program in favor of the other. | https://en.wikipedia.org/wiki/Fork_(system_call) |
The fork operation creates a separate address space for the child. The child process has an exact copy of all the memory segments of the parent process. In modern UNIX variants that follow the virtual memory model from SunOS-4.0, copy-on-write semantics are implemented and the physical memory need not be actually copied. | https://en.wikipedia.org/wiki/Fork_(system_call) |
Instead, virtual memory pages in both processes may refer to the same pages of physical memory until one of them writes to such a page: then it is copied. This optimization is important in the common case where fork is used in conjunction with exec to execute a new program: typically, the child process performs only a small set of actions before it ceases execution of its program in favour of the program to be started, and it requires very few, if any, of its parent's data structures. | https://en.wikipedia.org/wiki/Fork_(system_call) |
When a process calls fork, it is deemed the parent process and the newly created process is its child. After the fork, both processes not only run the same program, but they resume execution as though both had called the system call. They can then inspect the call's return value to determine their status, child or parent, and act accordingly. | https://en.wikipedia.org/wiki/Fork_(system_call) |
In multitasking operating systems, the PCB stores data needed for correct and efficient process management. Though the details of these structures are system-dependent, common elements fall in three main categories: Process identification Process state Process controlStatus tables exist for each relevant entity, like describing memory, I/O devices, files and processes. Memory tables, for example, contain information about the allocation of main and secondary (virtual) memory for each process, authorization attributes for accessing memory areas shared among different processes, etc. I/O tables may have entries stating the availability of a device or its assignment to a process, the status of I/O operations, the location of memory buffers used for them, etc. Process identification data include a unique identifier for the process (almost invariably an integer) and, in a multiuser-multitasking system, data such as the identifier of the parent process, user identifier, user group identifier, etc. The process id is particularly relevant since it is often used to cross-reference the tables defined above, e.g. showing which process is using which I/O devices, or memory areas. Process state data define the status of a process when it is suspended, allowing the OS to restart it later. | https://en.wikipedia.org/wiki/Process_control_block |
This always includes the content of general-purpose CPU registers, the CPU process status word, stack and frame pointers, etc. During context switch, the running process is stopped and another process runs. The kernel must stop the execution of the running process, copy out the values in hardware registers to its PCB, and update the hardware registers with the values from the PCB of the new process. Process control information is used by the OS to manage the process itself. This includes: Process scheduling state – The state of the process in terms of "ready", "suspended", etc., and other scheduling information as well, such as priority value, the amount of time elapsed since the process gained control of the CPU or since it was suspended. Also, in case of a suspended process, event identification data must be recorded for the event the process is waiting for; Process structuring information – the process's children id's, or the id's of other processes related to the current one in some functional way, which may be represented as a queue, a ring or other data structures; Interprocess communication information – flags, signals and messages associated with the communication among independent processes; Process Privileges – allowed/disallowed access to system resources; Process State – new, ready, running, waiting, dead; Process Number (PID) – unique identification number for each process (also known as Process ID); Program Counter (PC) – a pointer to the address of the next instruction to be executed for this process; CPU Registers – register set where process needs to be stored for execution for running state; CPU Scheduling Information – information scheduling CPU time; Memory Management Information – page table, memory limits, segment table; Accounting Information – amount of CPU used for process execution, time limits, execution ID etc.; I/O Status Information – list of I/O devices allocated to the process. | https://en.wikipedia.org/wiki/Process_control_block |
In multithreaded computer programming, asynchronous method invocation (AMI), also known as asynchronous method calls or the asynchronous pattern is a design pattern in which the call site is not blocked while waiting for the called code to finish. Instead, the calling thread is notified when the reply arrives. Polling for a reply is an undesired option. | https://en.wikipedia.org/wiki/Asynchronous_method_invocation |
In multithreaded computing, the ABA problem occurs during synchronization, when a location is read twice, has the same value for both reads, and the read value being the same twice is used to conclude that nothing has happened in the interim; however, another thread can execute between the two reads and change the value, do other work, then change the value back, thus fooling the first thread into thinking nothing has changed even though the second thread did work that violates that assumption. The ABA problem occurs when multiple threads (or processes) accessing shared data interleave. Below is a sequence of events that illustrates the ABA problem: Process P 1 {\displaystyle P_{1}} reads value A from some shared memory location, P 1 {\displaystyle P_{1}} is preempted, allowing process P 2 {\displaystyle P_{2}} to run, P 2 {\displaystyle P_{2}} writes value B to the shared memory location P 2 {\displaystyle P_{2}} writes value A to the shared memory location P 2 {\displaystyle P_{2}} is preempted, allowing process P 1 {\displaystyle P_{1}} to run, P 1 {\displaystyle P_{1}} reads value A from the shared memory location, P 1 {\displaystyle P_{1}} determines that the shared memory value has not changed and continues.Although P 1 {\displaystyle P_{1}} can continue executing, it is possible that the behavior will not be correct due to the "hidden" modification in shared memory. | https://en.wikipedia.org/wiki/ABA_problem |
A common case of the ABA problem is encountered when implementing a lock-free data structure. If an item is removed from the list, deleted, and then a new item is allocated and added to the list, it is common for the allocated object to be at the same location as the deleted object due to MRU memory allocation. A pointer to the new item is thus often equal to a pointer to the old item, causing an ABA problem. | https://en.wikipedia.org/wiki/ABA_problem |
In multitype branching processes, individuals are not identical, but can be classified into n types. After each time step, an individual of type i will produce individuals of different types, and X i {\displaystyle \mathbf {X} _{i}} , a random vector representing the numbers of children in different types, satisfies a probability distribution on N n {\displaystyle \mathbb {N} ^{n}} . For example, consider the population of cancer stem cells (CSCs) and non-stem cancer cells (NSCCs). After each time interval, each CSC has probability p 1 {\displaystyle p_{1}} to produce two CSCs (symmetric division), probability p 2 {\displaystyle p_{2}} to produce one CSC and one NSCC (asymmetric division), probability p 3 {\displaystyle p_{3}} to produce one CSC (stagnation), and probability 1 − p 1 − p 2 − p 3 {\displaystyle 1-p_{1}-p_{2}-p_{3}} to produce nothing (death); each NSCC has probability p 4 {\displaystyle p_{4}} to produce two NSCCs (symmetric division), probability p 5 {\displaystyle p_{5}} to produce one NSCC (stagnation), and probability 1 − p 4 − p 5 {\displaystyle 1-p_{4}-p_{5}} to produce nothing (death). | https://en.wikipedia.org/wiki/Branching_processes |
In multivariable calculus, an initial value problem (IVP) is an ordinary differential equation together with an initial condition which specifies the value of the unknown function at a given point in the domain. Modeling a system in physics or other sciences frequently amounts to solving an initial value problem. In that context, the differential initial value is an equation which specifies how the system evolves with time given the initial conditions of the problem. | https://en.wikipedia.org/wiki/Initial-value_problem |
In multivariable calculus, an iterated integral is the result of applying integrals to a function of more than one variable (for example f ( x , y ) {\displaystyle f(x,y)} or f ( x , y , z ) {\displaystyle f(x,y,z)} ) in such a way that each of the integrals considers some of the variables as given constants. For example, the function f ( x , y ) {\displaystyle f(x,y)} , if y {\displaystyle y} is considered a given parameter, can be integrated with respect to x {\displaystyle x} , ∫ f ( x , y ) d x {\textstyle \int f(x,y)\,dx} . The result is a function of y {\displaystyle y} and therefore its integral can be considered. If this is done, the result is the iterated integral ∫ ( ∫ f ( x , y ) d x ) d y . | https://en.wikipedia.org/wiki/Iterated_integral |
{\displaystyle \int \left(\int f(x,y)\,dx\right)\,dy.} It is key for the notion of iterated integrals that this is different, in principle, from the multiple integral ∬ f ( x , y ) d x d y . {\displaystyle \iint f(x,y)\,dx\,dy.} | https://en.wikipedia.org/wiki/Iterated_integral |
In general, although these two can be different, Fubini's theorem states that under specific conditions, they are equivalent. The alternative notation for iterated integrals ∫ d y ∫ d x f ( x , y ) {\displaystyle \int dy\int dx\,f(x,y)} is also used. In the notation that uses parentheses, iterated integrals are computed following the operational order indicated by the parentheses starting from the most inner integral outside. In the alternative notation, writing ∫ d y ∫ d x f ( x , y ) {\textstyle \int dy\,\int dx\,f(x,y)} , the innermost integrand is computed first. | https://en.wikipedia.org/wiki/Iterated_integral |
In multivariable calculus, an iterated limit is a limit of a sequence or a limit of a function in the form lim m → ∞ lim n → ∞ a n , m = lim m → ∞ ( lim n → ∞ a n , m ) {\displaystyle \lim _{m\to \infty }\lim _{n\to \infty }a_{n,m}=\lim _{m\to \infty }\left(\lim _{n\to \infty }a_{n,m}\right)} , lim y → b lim x → a f ( x , y ) = lim y → b ( lim x → a f ( x , y ) ) {\displaystyle \lim _{y\to b}\lim _{x\to a}f(x,y)=\lim _{y\to b}\left(\lim _{x\to a}f(x,y)\right)} ,or other similar forms. An iterated limit is only defined for an expression whose value depends on at least two variables. To evaluate such a limit, one takes the limiting process as one of the two variables approaches some number, getting an expression whose value depends only on the other variable, and then one takes the limit as the other variable approaches some number. | https://en.wikipedia.org/wiki/Moore-Osgood_theorem |
In multivariable calculus, the implicit function theorem is a tool that allows relations to be converted to functions of several real variables. It does so by representing the relation as the graph of a function. There may not be a single function whose graph can represent the entire relation, but there may be such a function on a restriction of the domain of the relation. The implicit function theorem gives a sufficient condition to ensure that there is such a function. More precisely, given a system of m equations fi (x1, ..., xn, y1, ..., ym) = 0, i = 1, ..., m (often abbreviated into F(x, y) = 0), the theorem states that, under a mild condition on the partial derivatives (with respect to each yi ) at a point, the m variables yi are differentiable functions of the xj in some neighborhood of the point. As these functions can generally not be expressed in closed form, they are implicitly defined by the equations, and this motivated the name of the theorem.In other words, under a mild condition on the partial derivatives, the set of zeros of a system of equations is locally the graph of a function. | https://en.wikipedia.org/wiki/Implicit_function_theorem |
In multivariate analysis, canonical correspondence analysis (CCA) is an ordination technique that determines axes from the response data as a linear combination of measured predictors. CCA is commonly used in ecology in order to extract gradients that drive the composition of ecological communities. CCA extends Correspondence Analysis (CA) with regression, in order to incorporate predictor variables. | https://en.wikipedia.org/wiki/Canonical_correspondence_analysis |
In multivariate calculus, a differential or differential form is said to be exact or perfect (exact differential), as contrasted with an inexact differential, if it is equal to the general differential d Q {\displaystyle dQ} for some differentiable function Q {\displaystyle Q} in an orthogonal coordinate system (hence Q {\displaystyle Q} is a multivariable function whose variables are independent, as they are always expected to be when treated in multivariable calculus). An exact differential is sometimes also called a total differential, or a full differential, or, in the study of differential geometry, it is termed an exact form. The integral of an exact differential over any integral path is path-independent, and this fact is used to identify state functions in thermodynamics. | https://en.wikipedia.org/wiki/Exact_differential |
In multivariate quantitative genetics, a genetic correlation (denoted r g {\displaystyle r_{g}} or r a {\displaystyle r_{a}} ) is the proportion of variance that two traits share due to genetic causes, the correlation between the genetic influences on a trait and the genetic influences on a different trait estimating the degree of pleiotropy or causal overlap. A genetic correlation of 0 implies that the genetic effects on one trait are independent of the other, while a correlation of 1 implies that all of the genetic influences on the two traits are identical. The bivariate genetic correlation can be generalized to inferring genetic latent variable factors across > 2 traits using factor analysis. | https://en.wikipedia.org/wiki/Genetic_correlations |
Genetic correlation models were introduced into behavioral genetics in the 1970s–1980s. Genetic correlations have applications in validation of genome-wide association study (GWAS) results, breeding, prediction of traits, and discovering the etiology of traits & diseases. They can be estimated using individual-level data from twin studies and molecular genetics, or even with GWAS summary statistics. | https://en.wikipedia.org/wiki/Genetic_correlations |
Genetic correlations have been found to be common in non-human genetics and to be broadly similar to their respective phenotypic correlations, and also found extensively in human traits, dubbed the 'phenome'.This finding of widespread pleiotropy has implications for artificial selection in agriculture, interpretation of phenotypic correlations, social inequality, attempts to use Mendelian randomization in causal inference, the understanding of the biological origins of complex traits, and the design of GWASes. A genetic correlation is to be contrasted with environmental correlation between the environments affecting two traits (e.g. if poor nutrition in a household caused both lower IQ and height); a genetic correlation between two traits can contribute to the observed (phenotypic) correlation between two traits, but genetic correlations can also be opposite observed phenotypic correlations if the environment correlation is sufficiently strong in the other direction, perhaps due to tradeoffs or specialization. The observation that genetic correlations usually mirror phenotypic correlations is known as "Cheverud's Conjecture" and has been confirmed in animals and humans, and showed they are of similar sizes; for example, in the UK Biobank, of 118 continuous human traits, only 29% of their intercorrelations have opposite signs, and a later analysis of 17 high-quality UKBB traits reported correlation near-unity. | https://en.wikipedia.org/wiki/Genetic_correlations |
In multivariate statistics, a scree plot is a line plot of the eigenvalues of factors or principal components in an analysis. The scree plot is used to determine the number of factors to retain in an exploratory factor analysis (FA) or principal components to keep in a principal component analysis (PCA). The procedure of finding statistically significant factors or components using a scree plot is also known as a scree test. Raymond B. Cattell introduced the scree plot in 1966.A scree plot always displays the eigenvalues in a downward curve, ordering the eigenvalues from largest to smallest. According to the scree test, the "elbow" of the graph where the eigenvalues seem to level off is found and factors or components to the left of this point should be retained as significant. | https://en.wikipedia.org/wiki/Scree's_test |
In multivariate statistics, exploratory factor analysis (EFA) is a statistical method used to uncover the underlying structure of a relatively large set of variables. EFA is a technique within factor analysis whose overarching goal is to identify the underlying relationships between measured variables. It is commonly used by researchers when developing a scale (a scale is a collection of questions used to measure a particular research topic) and serves to identify a set of latent constructs underlying a battery of measured variables. It should be used when the researcher has no a priori hypothesis about factors or patterns of measured variables. | https://en.wikipedia.org/wiki/Exploratory_Factor_Analysis |
Measured variables are any one of several attributes of people that may be observed and measured. Examples of measured variables could be the physical height, weight, and pulse rate of a human being. Usually, researchers would have a large number of measured variables, which are assumed to be related to a smaller number of "unobserved" factors. | https://en.wikipedia.org/wiki/Exploratory_Factor_Analysis |
Researchers must carefully consider the number of measured variables to include in the analysis. EFA procedures are more accurate when each factor is represented by multiple measured variables in the analysis. EFA is based on the common factor model. | https://en.wikipedia.org/wiki/Exploratory_Factor_Analysis |
In this model, manifest variables are expressed as a function of common factors, unique factors, and errors of measurement. Each unique factor influences only one manifest variable, and does not explain correlations between manifest variables. Common factors influence more than one manifest variable and "factor loadings" are measures of the influence of a common factor on a manifest variable. | https://en.wikipedia.org/wiki/Exploratory_Factor_Analysis |
For the EFA procedure, we are more interested in identifying the common factors and the related manifest variables. EFA assumes that any indicator/measured variable may be associated with any factor. | https://en.wikipedia.org/wiki/Exploratory_Factor_Analysis |
When developing a scale, researchers should use EFA first before moving on to confirmatory factor analysis (CFA). EFA is essential to determine underlying factors/constructs for a set of measured variables; while CFA allows the researcher to test the hypothesis that a relationship between the observed variables and their underlying latent factor(s)/construct(s) exists. EFA requires the researcher to make a number of important decisions about how to conduct the analysis because there is no one set method. | https://en.wikipedia.org/wiki/Exploratory_Factor_Analysis |
In multivariate statistics, if ε {\displaystyle \varepsilon } is a vector of n {\displaystyle n} random variables, and Λ {\displaystyle \Lambda } is an n {\displaystyle n} -dimensional symmetric matrix, then the scalar quantity ε T Λ ε {\displaystyle \varepsilon ^{T}\Lambda \varepsilon } is known as a quadratic form in ε {\displaystyle \varepsilon } . | https://en.wikipedia.org/wiki/Quadratic_form_(statistics) |
In multivariate statistics, principal response curves (PRC) are used for analysis of treatment effects in experiments with a repeated measures design.First developed as a special form of redundancy analysis, PRC allow temporal trends in control treatments to be corrected for, which allows the user to estimate the effects of the treatment levels without them being hidden by the overall changes in the system. An additional advantage of the method in comparison to other multivariate methods is that it gives a quantification of the treatment response of individual species that are present in the different groups. == References == | https://en.wikipedia.org/wiki/Principal_response_curve |
In multivariate statistics, random matrices were introduced by John Wishart, who sought to estimate covariance matrices of large samples. Chernoff-, Bernstein-, and Hoeffding-type inequalities can typically be strengthened when applied to the maximal eigenvalue (i.e. the eigenvalue of largest magnitude) of a finite sum of random Hermitian matrices. Random matrix theory is used to study the spectral properties of random matrices—such as sample covariance matrices—which is of particular interest in high-dimensional statistics. Random matrix theory also saw applications in neuronal networks and deep learning, with recent work utilizing random matrices to show that hyper-parameter tunings can be cheaply transferred between large neural networks without the need for re-training.In numerical analysis, random matrices have been used since the work of John von Neumann and Herman Goldstine to describe computation errors in operations such as matrix multiplication. Although random entries are traditional "generic" inputs to an algorithm, the concentration of measure associated with random matrix distributions implies that random matrices will not test large portions of an algorithm's input space. | https://en.wikipedia.org/wiki/Empirical_singular_values_distribution |
In multivariate statistics, spectral clustering techniques make use of the spectrum (eigenvalues) of the similarity matrix of the data to perform dimensionality reduction before clustering in fewer dimensions. The similarity matrix is provided as an input and consists of a quantitative assessment of the relative similarity of each pair of points in the dataset. In application to image segmentation, spectral clustering is known as segmentation-based object categorization. | https://en.wikipedia.org/wiki/Spectral_clustering |
In multivariate statistics, the congruence coefficient is an index of the similarity between factors that have been derived in a factor analysis. It was introduced in 1948 by Cyril Burt who referred to it as unadjusted correlation. It is also called Tucker's congruence coefficient after Ledyard Tucker who popularized the technique. Its values range between -1 and +1. It can be used to study the similarity of extracted factors across different samples of, for example, test takers who have taken the same test. | https://en.wikipedia.org/wiki/Congruence_coefficient |
In multiview projection, up to six pictures of an object are produced, called primary views, with each projection plane parallel to one of the coordinate axes of the object. The views are positioned relative to each other according to either of two schemes: first-angle or third-angle projection. In each, the appearances of views may be thought of as being projected onto planes that form a six-sided box around the object. | https://en.wikipedia.org/wiki/Orthographic_projection_(geometry) |
Although six different sides can be drawn, usually three views of a drawing give enough information to make a three-dimensional object. These views are known as front view, top view and end view. Other names for these views include plan, elevation and section. | https://en.wikipedia.org/wiki/Orthographic_projection_(geometry) |
When the plane or axis of the object depicted is not parallel to the projection plane, and where multiple sides of an object are visible in the same image, it is called an auxiliary view. Thus isometric projection, dimetric projection and trimetric projection would be considered auxiliary views in multiview projection. A typical characteristic of multiview projection is that one axis of space is usually displayed as vertical. | https://en.wikipedia.org/wiki/Orthographic_projection_(geometry) |
In municipal waste water treatment, sludge dewatering and thickening is handled. Belt Thickener Belt Press Micro Filter Screw Press | https://en.wikipedia.org/wiki/Bellmer |
In munitions, white phosphorus burns readily with flames of 800 °C (1,472 °F). Incandescent particles from weapons using powdered white phosphorus as their payload produce extensive partial- and full-thickness burns, as will any attempt to handle burning submunitions without protective equipment. Phosphorus burns carry an increased risk of mortality due to the absorption of phosphorus into the body through the burned area with prolonged contact, which can result in liver, heart and kidney damage, and in some cases multiple organ failure. | https://en.wikipedia.org/wiki/White_phosphorus_munitions |
White phosphorus particles continue to burn until completely consumed or starved of oxygen. In the case of weapons using felt-impregnated submunitions, incomplete combustion may occur resulting in up to 15% of the WP content remaining unburned. Such submunitions can prove hazardous as they are capable of spontaneous re-ignition if crushed by personnel or vehicles. | https://en.wikipedia.org/wiki/White_phosphorus_munitions |
In some cases, injury is limited to areas of exposed skin because the smaller WP particles do not burn completely through personal clothing before being consumed. Due to the pyrophoric nature of WP, penetrating injuries are immediately treated by smothering the wound using water, damp cloth or mud, isolating it from oxygen until fragments can be removed: military forces will typically do so using a bayonet or knife where able. Bicarbonate solution is applied to the wound to neutralise any build-up of phosphoric acid, followed by removal of any remaining visible fragments: these are easily observed as they are luminescent in dark surroundings. Surgical debridement around the wound is used to avoid fragments too small to detect causing later systemic failure, with further treatment proceeding as with a thermal burn. | https://en.wikipedia.org/wiki/White_phosphorus_munitions |
In murder cases arising from the Indian Territory, Navassa Island, and the No Man's Land of the Oklahoma Panhandle, the Supreme Court has held that the Clause places no limits on the prosecution of crimes committed outside the territory of a state. The Clause does not require a jury drawn from the judicial division (a subset of a federal judicial district) within which the crime occurred; rather, the jury may be drawn from any division of the district. Nor does the Clause prevent the jury from being drawn solely from a judicial division, or any other subset of a judicial district (rather than the entire judicial district). | https://en.wikipedia.org/wiki/Vicinage_Clause |
In murine models, two distinct transcripts are produced from opposite strands of the il14 gene that are called IL-14α and IL-14β. The il14 locus is near the gene for LCK on chromosome 1 in humans. | https://en.wikipedia.org/wiki/Interleukin_14 |
In mus musculus (house mouse), TRPV2 functions as a protein coding gene. There is broad expression of TRPV2 in the thymus, placenta, cerebellum, and spleen; it is most commonly expressed in the thymus. The thymus is a lymphoid organ involved in the function of the immune system, where T cells mature. T cells are an important component to the adaptive immune system, because it is where the body adapts to foreign substances; this demonstrates TRPV2's importance in the immune system. | https://en.wikipedia.org/wiki/TRPV2 |
TRPV2 in mus musculus is also activated by hypo-osmolarity and cell stretching, indicating that TRPV2 plays a role in mechanotransduction in mice as well. In experiments with knockout mice (TRPV2KO mice), it was found that TRPV2 is expressed in brown adipocytes and in brown adipose tissue (BAT). It can be concluded that TRPV2 plays a role in BAT thermogenesis in mice, since it was found that a lack of TRPV2 impairs this thermogenesis in BAT; given these results, this could be a target for human obesity therapy. | https://en.wikipedia.org/wiki/TRPV2 |
In muscle physiology, physiological cross-sectional area (PCSA) is the area of the cross section of a muscle perpendicular to its fibers, generally at its largest point. It is typically used to describe the contraction properties of pennate muscles. It is not the same as the anatomical cross-sectional area (ACSA), which is the area of the crossection of a muscle perpendicular to its longitudinal axis. In a non-pennate muscle the fibers are parallel to the longitudinal axis, and therefore PCSA and ACSA coincide. | https://en.wikipedia.org/wiki/Physiological_cross-sectional_area |
In museum collections it is common for the dry material to greatly exceed the amount of material that is preserved in alcohol. The shells minus their soft parts are kept in card trays within drawers or in glass tubes, often as lots (a lot is a collection of a single species taken from a single locality on a single occasion). Shell collections sometimes suffer from Byne's disease which also affects birds eggs. The study of dry mollusc shells is called conchology as distinct from malacology (wet specimens). | https://en.wikipedia.org/wiki/Zoological_specimen |
In museum specimens, the thin bill is clear and there is a long exposed nasal groove along the bill. The rictal bristles are short and few and the feathering at the base of the beak is reduced giving a very pointed face profile. The lower mandible is not flesh coloured in tytleri as in most trochiloides and it is not dark black as in Phylloscopus collybita tristis. They do not have any wing bars. | https://en.wikipedia.org/wiki/Tytler's_leaf_warbler |
In music a distance model is the alternation of two different intervals to create a non-diatonic musical mode such as the 1:3 distance model, the alternation of semitones and minor thirds: C-E♭-E-G-A♭-B-C. This scale is also an example of polymodal chromaticism as it includes both the tonic and dominant as well as "'two of the most typical degrees from both major and minor' (E and B, E♭ and A♭, respectively) ( p.132)".The most common distance model is the 1:2, also known as the octatonic scale (set type 8-28), followed by 1:3 and 1:5, also known as set type 4-9, which is a subset of the 1:2 model. Set type 4-9 has also been referred to as a "Z-Cell." | https://en.wikipedia.org/wiki/Distance_model |
In music a mixed-interval chord is a chord not characterized by one consistent interval. Chords characterized by one consistent interval, or primarily but with alterations, are equal-interval chords. Mixed interval chords "lend themselves particularly" to atonal music since they tend to be dissonant. | https://en.wikipedia.org/wiki/Equal-interval_chord |
Equal-interval chords are often of indeterminate root and mixed-interval chords are also often best characterized by their interval content. "Equal-interval chords are often altered to make them 'impure' as in the case of quartal and quintal chords with tritones, chords based on seconds with varying intervals between the seconds." == References == | https://en.wikipedia.org/wiki/Equal-interval_chord |
In music a time point or timepoint (point in time) is "an instant, analogous to a geometrical point in space". Because it has no duration, it literally cannot be heard, but it may be used to represent "the point of initiation of a single pitch, the repetition of a pitch, or a pitch simultaneity", therefore the beginning of a sound, rather than its duration. It may also designate the release of a note or the point within a note at which something changes (such as dynamic level). | https://en.wikipedia.org/wiki/Time_point |
Other terms often used in music theory and analysis are attack point and starting point. Milton Babbitt calls the distance from one time point, attack, or starting point to the next a time-point interval, independent of the durations of the sounding notes which may be either shorter than the time-point interval (resulting in a silence before the next time point), or longer (resulting in overlapping notes). Charles Wuorinen shortens this expression to just time interval. Other writers use the terms attack interval, or (translating the German Einsatzabstand), interval of entry, interval of entrance, or starting interval. | https://en.wikipedia.org/wiki/Time_point |
In music and dance, double-time is a type of meter and tempo or rhythmic feel by essentially halving the tempo resolution or metric division/level. It is also associated with specific time signatures such as 22. Contrast with half time. In jazz the term means using note values twice as fast as previously but without changing the pace of the chord progressions. | https://en.wikipedia.org/wiki/Double_time |
It is often used during improvised solos. "Double time doubling a rhythm pattern within its original bar structure. ": 1 2 3 4 1 2 3 4 1 2 3 4 It may help to picture the way musicians count each metric level in 4/4: quarter: 1 2 3 4 eighth: 1 & 2 & 3 & 4 & sixteenth: 1 e & a 2 e & a 3 e & a 4 e & a | https://en.wikipedia.org/wiki/Double_time |
In music and film/television production, some typical effects used in recording and amplified performances are: echo – to simulate the effect of reverberation in a large hall or cavern, one or several delayed signals are added to the original signal. To be perceived as echo, the delay has to be of order 35 milliseconds or above. Short of actually playing a sound in the desired environment, the effect of echo can be implemented using either analog or digital methods. Analog echo effects are implemented using tape delay or delay lines. | https://en.wikipedia.org/wiki/Sound_effect |
flanger – to create an unusual sound, a delayed signal is added to the original signal with a continuously variable delay (usually smaller than 10 ms). This effect is now done electronically using DSP, but originally the effect was created by playing the same recording on two synchronized tape players, and then mixing the signals together. As long as the machines were synchronized, the mix would sound more-or-less normal, but if the operator placed his finger on the flange of one of the players (hence "flanger"), that machine would slow down and its signal would fall out-of-phase with its partner, producing a phasing effect. | https://en.wikipedia.org/wiki/Sound_effect |
Once the operator took his finger off, the player would speed up until its tachometer was back in phase with the master, and as this happened, the phasing effect would appear to slide up the frequency spectrum. This phasing up-and-down the register can be performed rhythmically. phaser – another way of creating an unusual sound; the signal is split, a portion is filtered with an all-pass filter to produce a phase-shift, and then the unfiltered and filtered signals are mixed. | https://en.wikipedia.org/wiki/Sound_effect |
The phaser effect was originally used as a simpler implementation of the flanger effect since delays were difficult to implement with analog equipment. Phasers are often used to give a "synthesized" or electronic effect to natural sounds, such as human speech. The voice of C-3PO from Star Wars was created by taking the actor's voice and treating it with a phaser. | https://en.wikipedia.org/wiki/Sound_effect |
chorus – a delayed signal is added to the original signal with a constant delay. The delay has to be short in order not to be perceived as echo, but above 5 ms to be audible. If the delay is too short, it will destructively interfere with the un-delayed signal and create a flanging effect. | https://en.wikipedia.org/wiki/Sound_effect |
Often, the delayed signals will be slightly pitch shifted to more realistically convey the effect of multiple voices. equalization – different frequency bands are attenuated or boosted to produce desired spectral characteristics. Moderate use of equalization (often abbreviated as "EQ") can be used to "fine-tune" the tone quality of a recording; extreme use of equalization, such as heavily cutting a certain frequency can create more unusual effects. | https://en.wikipedia.org/wiki/Sound_effect |
filtering – Equalization is a form of filtering. In the general sense, frequency ranges can be emphasized or attenuated using low-pass, high-pass, band-pass or band-stop filters. Band-pass filtering of voice can simulate the effect of a telephone because telephones use band-pass filters. | https://en.wikipedia.org/wiki/Sound_effect |
overdrive effects such as the use of a fuzz box can be used to produce distorted sounds, such as for imitating robotic voices or to simulate distorted radiotelephone traffic (e.g., the radio chatter between starfighter pilots in the science fiction film Star Wars). The most basic overdrive effect involves clipping the signal when its absolute value exceeds a certain threshold. pitch shift – similar to pitch correction, this effect shifts a signal up or down in pitch. | https://en.wikipedia.org/wiki/Sound_effect |
For example, a signal may be shifted an octave up or down. This is usually applied to the entire signal, and not to each note separately. One application of pitch shifting is pitch correction. | https://en.wikipedia.org/wiki/Sound_effect |
Here a musical signal is tuned to the correct pitch using digital signal processing techniques. This effect is ubiquitous in karaoke machines and is often used to assist pop singers who sing out of tune. It is also used intentionally for aesthetic effect in such pop songs as Cher's "Believe" and Madonna's "Die Another Day". | https://en.wikipedia.org/wiki/Sound_effect |
time stretching – the opposite of pitch shift, that is, the process of changing the speed of an audio signal without affecting its pitch. resonators – emphasize harmonic frequency content on specified frequencies. | https://en.wikipedia.org/wiki/Sound_effect |
robotic voice effects are used to make an actor's voice sound like a synthesized human voice. synthesizer – generate artificially almost any sound by either imitating natural sounds or creating completely new sounds. modulation – to change the frequency or amplitude of a carrier signal in relation to a predefined signal. | https://en.wikipedia.org/wiki/Sound_effect |
Ring modulation, also known as amplitude modulation, is an effect made famous by Doctor Who's Daleks and commonly used throughout sci-fi. compression – the reduction of the dynamic range of a sound to avoid unintentional fluctuation in the dynamics. Level compression is not to be confused with audio data compression, where the amount of data is reduced without affecting the amplitude of the sound it represents. | https://en.wikipedia.org/wiki/Sound_effect |
3D audio effects – place sounds outside the stereo basis sound on sound – to record over a recording without erasing. Originally accomplished by disabling the tape erase magnet. This allowed an artist to make parts of the work sound like a duet. reverse echo – a swelling effect created by reversing an audio signal and recording echo and/or delay whilst the signal runs in reverse. When played back forward the last echos are heard before the effected sound creating a rush like swell preceding and during playback. | https://en.wikipedia.org/wiki/Sound_effect |
In music and jazz harmony, the Stomp progression is an eight-bar chord progression named for its use in the "stomp" section of the composition "King Porter Stomp" (1923) by Jelly Roll Morton. The composition was later arranged by Fletcher Henderson, adding greater emphasis on the Trio section, containing a highly similar harmonic loop to that found in the Stomp section. It was one of the most popular tunes of the swing era, and the Stomp progression was often used.Following the success of "King Porter Stomp", many other compositions were named after the tune, although many of these "stomps" did not necessarily employ the stomp progression. | https://en.wikipedia.org/wiki/Stomp_progression |
In music and jazz improvisation, a melodic pattern (or motive) is a cell or germ serving as the basis for repetitive pattern. It is a figure that can be used with any scale. It is used primarily for solos because, when practiced enough, it can be extremely useful when improvising. "Sequence" refers to the repetition of a part at a higher or lower pitch, and melodic sequence is differentiated from harmonic sequence. | https://en.wikipedia.org/wiki/Melodic_pattern |
One example of melodic motive and sequence are the pitches of the first line, "Send her victorious," repeated, a step lower, in the second line, "Happy and glorious," from "God Save the Queen". "A melodic pattern is just what the name implies: a melody with some sort of fixed pattern to it." "The strong theme or motive is stated. It is repeated more or less exactly, but at a different pitch level." | https://en.wikipedia.org/wiki/Melodic_pattern |
In music and music theory, a hexatonic scale is a scale with six pitches or notes per octave. Famous examples include the whole-tone scale, C D E F♯ G♯ A♯ C; the augmented scale, C D♯ E G A♭ B C; the Prometheus scale, C D E F♯ A B♭ C; and the blues scale, C E♭ F G♭ G B♭ C. A hexatonic scale can also be formed by stacking perfect fifths. This results in a diatonic scale with one note removed (for example, A C D E F G). | https://en.wikipedia.org/wiki/Augmented_scale |
In music and music theory, a non-retrogradable rhythm is a rhythmic palindrome, i.e., a pattern of note durations that is read or performed the same either forwards or backwards. The term is used most frequently in the context of the music of Olivier Messiaen. For example, such rhythms occur in the "Liturgie de cristal" and "Danse de la fureur, pour les sept trompettes"—the first and sixth movements—of Messiaen's Quatuor pour la fin du temps. | https://en.wikipedia.org/wiki/Retrograde_(music) |
In music and music theory, a tenth is the note ten scale degrees from the root of a chord and also the interval between the root and the tenth. Since there are only seven degrees in a diatonic scale the tenth degree is the same as the mediant and the interval of a tenth is a compound third. | https://en.wikipedia.org/wiki/Minor_tenth |
In music and musical analysis, a subsidiary chord is an elaboration of a principal harmonic chord in a chord progression. If the principal chord (X) is partially replaced by the subsidiary (Y), there are three possible positions - beginning, middle, and end - for the subsidiary: X–Ya Y–X X–Y–XFor example, a subsidiary chord in a modulation. A subsidiary chord may be a chord with related function and/or sharing pitches, for example in E major, C♯m (C♯-E-G♯) as a subsidiary for E (E-G♯-B), which share two of three pitches and are related as tonic parallel (vi) and tonic (I). | https://en.wikipedia.org/wiki/Subsidiary_chord |
In music and other performing arts, the phrase ad libitum (; from Latin for 'at one's pleasure' or 'as you desire'), often shortened to "ad lib" (as an adjective or adverb) or "ad-lib" (as a verb or noun), refers to various forms of improvisation. The roughly synonymous phrase a bene placito ('in accordance with good pleasure') is less common but, in its Italian form a piacere, has entered the musical lingua franca (see below). The phrase "at liberty" is often associated mnemonically (because of the alliteration of the lib- syllable), although it is not the translation (there is no cognation between libitum and liber). Libido is the etymologically closer cognate known in English. | https://en.wikipedia.org/wiki/Ad_lib |
In music and prosody, arsis (; plural arses, ) and thesis (; plural theses, ) are respectively the stronger and weaker parts of a musical measure or poetic foot. However, because of contradictions in the original definitions, writers use these words in different ways. In music, arsis is an unaccented note (upbeat), while the thesis is the downbeat. However, in discussions of Latin and modern poetry the word arsis is generally used to mean the stressed syllable of the foot, that is, the ictus.Since the words are used in contradictory ways, the authority on Greek metre Martin West recommends abandoning them and using substitutes such as ictus for the downbeat when discussing ancient poetry. However, the use of the word ictus itself is very controversial. | https://en.wikipedia.org/wiki/Arsis_and_thesis |
In music cognition and musical analysis, the study of melodic expectation considers the engagement of the brain's predictive mechanisms in response to music. For example, if the ascending musical partial octave "do-re-mi-fa-sol-la-ti-..." is heard, listeners familiar with Western music will have a strong expectation to hear or provide one more note, "do", to complete the octave. Melodic expectation can be considered at the esthesic level, in which case the focus lies on the listener and its response to music. It can be considered at the neutral level, in which case the focus switches to the actual musical content, such as the "printed notes themselves". At the neutral level, the observer may consider logical implications projected onto future elements by past elements or derive statistical observations from information theory. | https://en.wikipedia.org/wiki/Melodic_expectation |
In music cognition, melodic fission (also known as melodic or auditory streaming, or stream segregation), is a phenomenon in which one line of pitches (an auditory stream) is heard as two or more separate melodic lines. This occurs when a phrase contains groups of pitches at two or more distinct registers or with two or more distinct timbres. The term appears to stem from a 1973 paper by W. J. Dowling. In music analysis and, more specifically, in Schenkerian analysis, the phenomenon is often termed compound melody.In psychophysics, auditory scene analysis is the process by which the brain separates and organizes sounds into perceptually distinct groups, known as auditory streams. The counterpart to melodic fission is melodic fusion. | https://en.wikipedia.org/wiki/Melodic_fission |
In music composition the four-group is the basic group of permutations in the twelve-tone technique. In that instance the Cayley table is written; | https://en.wikipedia.org/wiki/Klein_4-group |
In music education, color is typically used in method books to highlight new material. Stimuli received through several senses excite more neurons in several localized areas of the cortex, thereby reinforcing the learning process and improving retention. This information has been proven by other researchers; Chute (1978) reported that "elementary students who viewed a colored version of an instructional film scored significantly higher on both immediate and delayed tests than did students who viewed a monochrome version". | https://en.wikipedia.org/wiki/Colored_music_notation |
In music for stringed instruments, especially guitar, an open chord (open-position chord) is a chord that includes one or more strings that are not fingered. An open string vibrates freely, whereas a fingered string will be partially dampened unless fingered with considerable pressure, which is difficult for beginner players. In an open chord, the unfingered strings are undampened, and the player is able to exert maximum pressure on the fretted strings, to avoid unwanted dampening. On a regular six-string guitar, an open chord can have from one to six open strings sounding. | https://en.wikipedia.org/wiki/Open_chord |
In contrast, all of the strings are fingered for a barre chord, which requires greater technique to be allowed to ring freely. To dampen a barre chord, a player simply needs to relax the fingers. Fully dampening an open chord requires the player to roll the fingers of the left hand over the open strings, or else dampen with the right hand. | https://en.wikipedia.org/wiki/Open_chord |
Guitarists use capos, which are devices that clamp down the strings to create a movable nut, to play open chords in different keys. With a capo on the first fret, the guitarist can finger the shape of the open A minor chord, but the result will be a B♭ minor chord. Open chords on guitar are used in a wide range of popular music and traditional music styles. | https://en.wikipedia.org/wiki/Open_chord |
In music from Western culture, a diminished octave () is an interval produced by narrowing a perfect octave by a chromatic semitone. As such, the two notes are denoted by the same letter but have different accidentals. For instance, the interval from C4 to C5 is a perfect octave, twelve semitones wide, and both the intervals from C♯4 to C5 and from C4 to C♭5 are diminished octaves, spanning eleven semitones. Being diminished, it is considered a dissonant interval.The diminished octave is enharmonically equivalent to the major seventh. == References == | https://en.wikipedia.org/wiki/Diminished_octave |
In music from Western culture, a seventh is a musical interval encompassing seven staff positions (see Interval number for more details), and the major seventh is one of two commonly occurring sevenths. It is qualified as major because it is the larger of the two. The major seventh spans eleven semitones, its smaller counterpart being the minor seventh, spanning ten semitones. For example, the interval from C to B is a major seventh, as the note B lies eleven semitones above C, and there are seven staff positions from C to B. Diminished and augmented sevenths span the same number of staff positions, but consist of a different number of semitones (nine and twelve). | https://en.wikipedia.org/wiki/Just_major_seventh |
The intervals from the tonic (keynote) in an upward direction to the second, to the third, to the sixth, and to the seventh scale degrees (of a major scale are called major. The easiest way to locate and identify the major seventh is from the octave rather than the unison, and it is suggested that one sings the octave first. For example, the most commonly cited example of a melody featuring a major seventh is the tonic-octave-major seventh of the opening to "(Somewhere) Over the Rainbow". | https://en.wikipedia.org/wiki/Just_major_seventh |
"Not many songwriters begin a melody with a major seventh interval; perhaps that's why there are few memorable examples." However, two songs provide exceptions to this generalisation: Cole Porter's "I love you" (1944) opens with a descending major seventh and Jesse Harris's "Don't Know Why",(made famous by Norah Jones in her 2002 debut album, Come Away with Me), starts with an ascending one. In the refrain of "Bali Hai" in "South Pacific," the third tone ("Hai") is a major seventh to the first ("Ba-"). | https://en.wikipedia.org/wiki/Just_major_seventh |
The major seventh occurs most commonly built on the root of major triads, resulting in the chord type also known as major seventh chord or major-major seventh chord: including I7 and IV7 in major. "Major seven chords add jazziness to a musical passage. Alone, a major seventh interval can sound ugly. | https://en.wikipedia.org/wiki/Just_major_seventh |
"A major seventh in just intonation most often corresponds to a pitch ratio of 15:8 (); in 12-tone equal temperament, a major seventh is equal to eleven semitones, or 1100 cents, about 12 cents wider than the 15:8 major seventh. In 24-tone equal temperament a supermajor seventh, semiaugmented seventh or, semidiminished octave, 23 quarter-tones, is 1150 cents (). The small major seventh is a ratio of 9:5, now identified as a just minor seventh. | https://en.wikipedia.org/wiki/Just_major_seventh |
35:18, or 1151.23 cents, is the ratio of the septimal semi-diminished octave. The 15:8 just major seventh occurs arises in the extended C major scale between C & B and F & E. The major seventh interval is considered one of the most dissonant intervals after its inversion the minor second. For this reason, its melodic use is infrequent in classical music. | https://en.wikipedia.org/wiki/Just_major_seventh |
However, in the genial Gavotte from J.S. Bach’s Partita in E major for solo violin, a major seventh features both as a chord (bar 1) and as a melodic interval (bar 5): Another piece that makes more dramatic use of the major seventh is "The Hut on Fowl's Legs" from Mussorgsky's piano suite Pictures at an Exhibition (1874). Another is the closing duet from Verdi's Aida, "O terra addio". | https://en.wikipedia.org/wiki/Just_major_seventh |
During the early 20th century, the major seventh was used increasingly both as a melodic and a harmonic interval, particularly by composers of the Second Viennese School. Anton Webern's Variations for Piano, Op. | https://en.wikipedia.org/wiki/Just_major_seventh |
27, opens with a major seventh and the interval recurs frequently throughout the piece. Under equal temperament this interval is enharmonically equivalent to a diminished octave (which has a similar musical use to the augmented unison). The major seventh chord is however very common in jazz, especially 'cool' jazz, and has a characteristically soft and sweet sound: think of the first chord in "The Girl from Ipanema". The major seventh chord consists of the first, third, fifth and seventh degrees (notes) of the major scale. In the key of C, it comprises the notes C E G and B. | https://en.wikipedia.org/wiki/Just_major_seventh |
In music from Western culture, a sixth is a musical interval encompassing six note letter names or staff positions (see Interval number for more details), and the major sixth is one of two commonly occurring sixths. It is qualified as major because it is the larger of the two. The major sixth spans nine semitones. Its smaller counterpart, the minor sixth, spans eight semitones. | https://en.wikipedia.org/wiki/Pythagorean_major_sixth |
For example, the interval from C up to the nearest A is a major sixth. It is a sixth because it encompasses six note letter names (C, D, E, F, G, A) and six staff positions. It is a major sixth, not a minor sixth, because the note A lies nine semitones above C. Diminished and augmented sixths (such as C♯ to A♭ and C to A♯) span the same number of note letter names and staff positions, but consist of a different number of semitones (seven and ten, respectively). | https://en.wikipedia.org/wiki/Pythagorean_major_sixth |
The intervals from the tonic (keynote) in an upward direction to the second, to the third, to the sixth, and to the seventh scale degrees (of a major scale are called major. A commonly cited example of a melody featuring the major sixth as its opening is "My Bonnie Lies Over the Ocean".The major sixth is one of the consonances of common practice music, along with the unison, octave, perfect fifth, major and minor thirds, minor sixth, and (sometimes) the perfect fourth. In the common practice period, sixths were considered interesting and dynamic consonances along with their inverses the thirds. | https://en.wikipedia.org/wiki/Pythagorean_major_sixth |
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