Split (1)

train · 253k rows

page_content stringlengths 51 3.15k
Permeability (electromagnetism) Paramagnetism Magnetic_permittivity > Paramagnetism Paramagnetism is a form of magnetism which occurs only in the presence of an externally applied magnetic field. Paramagnetic materials are attracted to magnetic fields, hence have a relative magnetic permeability greater than one (or, equivalently, a positive magnetic susceptibility). The magnetic moment induced by the applied field is linear in the field strength, and it is rather weak.
Superluminal motion Explanation Superluminal_jet > Explanation This means that the apparent speed as calculated above is greater than the actual speed. Correspondingly, if the object is moving away from the Earth, the above calculation underestimates the actual speed. This effect in itself does not generally lead to superluminal motion being observed.
Pascal programming language Dialects Pascal_(command) > History > Dialects Wirth's example compiler meant to propagate the language, the Pascal-P system, used a subset of the language designed to be the minimal subset of the language that could compile itself. The idea was that this could allow boostrapping the compiler, which would then be extended to full Pascal language status. This was done with several compilers, but one notable exception was UCSD Pascal, which was based on Pascal-P2. It kept the subset status of the language based on the idea that this would run better on the new (then) microprocessors with limited memory.
Programming pattern History Software_design_patterns > History Design Patterns: Elements of Reusable Object-Oriented Software. Addison-Wesley. ISBN 978-0-201-63361-0.
Neural circuit Early study Neural_circuit > Early study They showed theoretically that networks of artificial neurons could implement logical, arithmetic, and symbolic functions. Simplified models of biological neurons were set up, now usually called perceptrons or artificial neurons. These simple models accounted for neural summation (i.e., potentials at the post-synaptic membrane will summate in the cell body). Later models also provided for excitatory and inhibitory synaptic transmission.
Solow growth model Long-run implications Exogenous_growth_model > Background > Long-run implications A standard Solow model predicts that in the long run, economies converge to their steady state equilibrium and that permanent growth is achievable only through technological progress. Both shifts in saving and in populational growth cause only level effects in the long-run (i.e. in the absolute value of real income per capita). An interesting implication of Solow's model is that poor countries should grow faster and eventually catch-up to richer countries. This convergence could be explained by: Lags in the diffusion on knowledge.
Pipelined processor Summary Instruction_pipelining In computer engineering, instruction pipelining is a technique for implementing instruction-level parallelism within a single processor. Pipelining attempts to keep every part of the processor busy with some instruction by dividing incoming instructions into a series of sequential steps (the eponymous "pipeline") performed by different processor units with different parts of instructions processed in parallel.
Stein-Rosenberg theorem Summary Stein-Rosenberg_theorem 0 < ρ ( T 1 ) < ρ ( T J ) < 1 {\displaystyle 0<\rho (T_{1})<\rho (T_{J})<1} . 1 = ρ ( T J ) = ρ ( T 1 ) {\displaystyle 1=\rho (T_{J})=\rho (T_{1})} . 1 < ρ ( T J ) < ρ ( T 1 ) {\displaystyle 1<\rho (T_{J})<\rho (T_{1})} .The proof uses the Perron-Frobenius theorem for non-negative matrices.
Group A beta-hemolytic streptococcus Disease Group_A_beta-hemolytic_streptococcus > Disease Erysipelas and cellulitis are characterized by multiplication and lateral spread of S. pyogenes in deep layers of the skin. S. pyogenes invasion and multiplication in the fascia can lead to necrotizing fasciitis, a life-threatening condition which requires prompt surgical intervention to reduce morbidity and mortality. The bacterium is found in neonatal infections.Infections due to certain strains of S. pyogenes can be associated with the release of bacterial toxins.
Filling area conjecture Definitions and statement of the conjecture Filling_area_conjecture > Definitions and statement of the conjecture None of these transformations modifies the area of the surface nor the length of the curves drawn on it, which are the magnitudes relevant to the problem. The surface can be removed from Euclidean space altogether, obtaining a Riemannian surface, which is an abstract smooth surface with a Riemannian metric that encodes the lengths and area. Reciprocally, according to the Nash-Kuiper theorem, any Riemannian surface with boundary can be embedded in Euclidean space preserving the lengths and area specified by the Riemannian metric.
GPS time Receiver in continuous operation Global_positioning_systems > Principles > Receiver in continuous operation In general, a tracker can (a) improve receiver position and time accuracy, (b) reject bad measurements, and (c) estimate receiver speed and direction. The disadvantage of a tracker is that changes in speed or direction can be computed only with a delay, and that derived direction becomes inaccurate when the distance traveled between two position measurements drops below or near the random error of position measurement. GPS units can use measurements of the Doppler shift of the signals received to compute velocity accurately. More advanced navigation systems use additional sensors like a compass or an inertial navigation system to complement GPS.
Palifermin Drug target and mechanism of action Palifermin > Drug target and mechanism of action Keratinocyte growth factor (KGF) resides in the family of fibroblast growth factor (FGF). The drug's target is the KGF receptor. Through the binding of this drug to the aforementioned receptor, Palifermin stimulates epithelial cell proliferation, differentiation, and upregulation of cytoprotective mechanisms to reduce the symptoms of oral mucositis.
Water filtration plant Pretreatment Water_purifier > Treatment > Pretreatment Pumping and containment – The majority of water must be pumped from its source or directed into pipes or holding tanks. To avoid adding contaminants to the water, this physical infrastructure must be made from appropriate materials and constructed so that accidental contamination does not occur. Screening (see also screen filter) – The first step in purifying surface water is to remove large debris such as sticks, leaves, rubbish and other large particles which may interfere with subsequent purification steps. Most deep groundwater does not need screening before other purification steps.
Non-thermal microwave effect Summary Non-thermal_microwave_effect Non-thermal microwave effects or specific microwave effects have been posited in order to explain unusual observations in microwave chemistry. The main effect of the absorption of microwaves by dielectric materials is a brief displacement in the permanent dipoles which causes rotational entropy. Since the frequency of the microwave energy is much faster than the electrons can absorb, the resultant energy can cause frictional heating of nearby atoms or molecules. If the material is rigid there will be no release of rotational energy, and therefore no heating.
Sulfur isotope biogeochemistry Δ33S and Δ36S notation Sulfur_isotope_biogeochemistry > Calculations > Δ33S and Δ36S notation All kinetic and equilibrium isotope effects result from differences in atomic mass. As a result, a reaction that fractionates 34S will also fractionate 33S and 36S, and the fractionation factor for each isotope will be mathematically proportional to its mass. Because of the mathematical relationships of their masses, the observed relationships between δ34S, δ33S, and δ36S in most natural materials are approximately δ33S = 0.515 × δ34S and δ36S = 1.90 × δ34S. Rarely, natural processes can create deviations from this relationship, and these deviations are reported as Δ33S and Δ36S values, usually pronounced as "cap delta." These values are typically calculated as follows: Δ33S = 1000 × Δ36S = 1000 × However, the method for calculating Δ33S and Δ36S values is not standardized, and can differ among publications.
Trajectory Physics of trajectories Trajectory > Physics of trajectories Classical mechanics became a most prominent demonstration of the power of rational thought, i.e. reason, in science as well as technology. It helps to understand and predict an enormous range of phenomena; trajectories are but one example. Consider a particle of mass m {\displaystyle m} , moving in a potential field V {\displaystyle V} .
Mathematical recursion In computer science Recursive_step > In computer science The solution to the problem is then devised by combining the solutions obtained from the simpler versions of the problem. One example application of recursion is in parsers for programming languages. The great advantage of recursion is that an infinite set of possible sentences, designs or other data can be defined, parsed or produced by a finite computer program.
Cubic equation In mathematics Cardano's_formula > Applications > In mathematics Given the cosine (or other trigonometric function) of an arbitrary angle, the cosine of one-third of that angle is one of the roots of a cubic. The solution of the general quartic equation relies on the solution of its resolvent cubic. The eigenvalues of a 3×3 matrix are the roots of a cubic polynomial which is the characteristic polynomial of the matrix.
Acceleration (special relativity) History Acceleration_(special_relativity) > History But if r , y , z {\displaystyle r,y,z} are constant and φ {\displaystyle \varphi } is variable, they denote the transformation into its rest frame. 1911: Sommerfeld explicitly used the expression "proper acceleration" (German: Eigenbeschleunigung) for the quantity v ˙ 0 {\displaystyle {\dot {v}}_{0}} in v ˙ = v ˙ 0 ( 1 − β 2 ) 3 / 2 {\displaystyle {\dot {v}}={\dot {v}}_{0}\left(1-\beta ^{2}\right)^{3/2}} , which corresponds to (3a), as the acceleration in the momentary inertial frame. 1911: Herglotz explicitly used the expression "rest acceleration" (German: Ruhbeschleunigung) instead of proper acceleration.
Glossary of genetics (0–L) H Glossary_of_gene_expression_terms > H A statistic used in quantitative genetics that estimates the proportion of variation within a given phenotypic trait that is due to genetic variation between individuals in a particular population. Heritability is estimated by comparing the individual phenotypes of closely related individuals in the population. heterochromatin heterochromosome See allosome.
Introduction to electromagnetism Electric and magnetic fields Introduction_to_electromagnetism > Electric and magnetic fields Classical electromagnetism is fully described by the Lorentz force alongside a set of equations called Maxwell's equations. The first of these equations is known as Gauss's law. It describes the electric field produced by charged particles and by charge distributions.
Euler–Bernoulli beam equation Static beam equation Euler–Bernoulli_beam_theory > Static beam equation Explicitly, for a beam whose axis is oriented along x {\displaystyle x} with a loading along z {\displaystyle z} , the beam's cross section is in the y z {\displaystyle yz} plane, and the relevant second moment of area is I = ∬ z 2 d y d z , {\displaystyle I=\iint z^{2}\;dy\;dz,} where it is assumed that the centroid of the cross section occurs at y = z = 0 {\displaystyle y=z=0} . Often, the product E I {\displaystyle EI} (known as the flexural rigidity) is a constant, so that E I d 4 w d x 4 = q ( x ) . {\displaystyle EI{\frac {\mathrm {d} ^{4}w}{\mathrm {d} x^{4}}}=q(x).\,} This equation, describing the deflection of a uniform, static beam, is used widely in engineering practice.
Virtual Storage Access Method VSAM files Virtual_Storage_Access_Method > VSAM files The physical organization of VSAM data sets differs considerably from the organizations used by other access methods, as follows. A VSAM file is defined as a cluster of VSAM components, e.g., for KSDS a DATA component and an INDEX component.
Speed of light (cellular automaton) Faster than light propagation Speed_of_light_(cellular_automaton) > Faster than light propagation Certain patterns can appear to move at a speed greater than one cell per generation, but like faster than light phenomena in physics this is illusory. An example is the "Star Gate", an arrangement of three converging gliders that will mutually annihilate on collision. If a lightweight spaceship (LWSS) hits the colliding gliders, it will appear to move forwards by 11 cells in only 6 generations, and thus travel faster than light. This illusion happens because the glider annihilation reaction proceeds by the creation and soon-after destruction of another LWSS.
Heat of dilution Definition Heat_of_dilution > Definition Mathematically, the molar differential heat of dilution is denoted as: where ∂∆ni is the infinitesimal change or differential of mole number of the dilution. The integral heat of dilution, however, is viewed on a macro scale. With respect to the integral heat, consider a process in which a certain amount of solution diluted from an initial concentration to a final concentration. The enthalpy change in this process, normalized by the mole number of solute, is evaluated as the molar integral heat of dilution. Mathematically, the molar integral heat of dilution is denoted as: If the infinite amount of solvent is added to a solution with a known concentration of solute, the corresponding change of enthalpy is called as integral heat of dilution to infinite dilution.The dilution between two concentrations of the solute is associated to an intermediary heat of dilution by mole of solute.
Completing the square Complex numbers Complete_the_square > Other applications > Complex numbers Consider the expression where z and b are complex numbers, z* and b* are the complex conjugates of z and b, respectively, and c is a real number. Using the identity \|u\|2 = uu* we can rewrite this as which is clearly a real quantity. This is because As another example, the expression where a, b, c, x, and y are real numbers, with a > 0 and b > 0, may be expressed in terms of the square of the absolute value of a complex number. Define Then so
Motor function Direct perception Motor_control > Perception in motor control > Information based control > Direct perception The role of perception is to provide information that specifies how actions should be organized and controlled, and the motor system is "tuned" to respond to specific type of information in particular ways. Through this relationship, control of the motor system and the execution of actions is dictated by the information of the environment. As an example, a doorway "affords" passing through, but a wall does not.
Ten-dimensional space Dualities String_Theory > Fundamentals > Dualities For example, Montonen–Olive duality is an example of an S-duality relationship between quantum field theories. The AdS/CFT correspondence is an example of a duality that relates string theory to a quantum field theory. If two theories are related by a duality, it means that one theory can be transformed in some way so that it ends up looking just like the other theory. The two theories are then said to be dual to one another under the transformation. Put differently, the two theories are mathematically different descriptions of the same phenomena.
Micrometer (device) Testing Micrometer_screw_gauge > Calibration: testing and adjusting > Testing The solution is simply conscientiousness—cleaning, patience, due care and attention, and repeated measurements (good repeatability assures the calibrator that their technique is working correctly). Calibration typically checks the error at 3 to 5 points along the range. Only one can be adjusted to zero.
Parallel programming model Implicit interaction Parallel_programming_model > Classification of parallel programming models > Process interaction > Implicit interaction In an implicit model, no process interaction is visible to the programmer and instead the compiler and/or runtime is responsible for performing it. Two examples of implicit parallelism are with domain-specific languages where the concurrency within high-level operations is prescribed, and with functional programming languages because the absence of side-effects allows non-dependent functions to be executed in parallel. However, this kind of parallelism is difficult to manage and functional languages such as Concurrent Haskell and Concurrent ML provide features to manage parallelism explicitly and correctly.
Polychromatic symmetry Group theory Polychromatic_symmetry > Group theory Initial research by Wittke and Garrido (1959) and by Niggli and Wondratschek (1960) identified the relation between the colour groups of an object and the subgroups of the object's geometric symmetry group. In 1961 van der Waerden and Burckhardt built on the earlier work by showing that colour groups can be defined as follows: in a colour group of a pattern (or object) each of its geometric symmetry operations s is associated with a permutation σ of the k colours in such a way that all the pairs (s,σ) form a group. Senechal showed that the permutations are determined by the subgroups of the geometric symmetry group G of the uncoloured pattern. When each symmetry operation in G is associated with a unique colour permutation the pattern is said to be perfectly coloured.The Waerden-Burckhardt theory defines a k-colour group G(H) as being determined by a subgroup H of index k in the symmetry group G. If the subgroup H is a normal subgroup then the quotient group G/H permutes all the colours.
Homology theory Singular homology Homology_theory > Types of homology > Singular homology Using simplicial homology example as a model, one can define a singular homology for any topological space X. A chain complex for X is defined by taking Cn to be the free abelian group (or free module) whose generators are all continuous maps from n-dimensional simplices into X. The homomorphisms ∂n arise from the boundary maps of simplices.
Class system Class conflict Social_division > Class conflict Class conflict, frequently referred to as "class warfare" or "class struggle", is the tension or antagonism which exists in society due to competing socioeconomic interests and desires between people of different classes. For Marx, the history of class society was a history of class conflict. He pointed to the successful rise of the bourgeoisie and the necessity of revolutionary violence—a heightened form of class conflict—in securing the bourgeois rights that supported the capitalist economy. Marx believed that the exploitation and poverty inherent in capitalism were a pre-existing form of class conflict. Marx believed that wage labourers would need to revolt to bring about a more equitable distribution of wealth and political power.
Converting (metallurgy) Summary Converting_(metallurgy) Converting is a type of metallurgical smelting that includes several processes; the most commercially important form is the treatment of molten metal sulfides to produce crude metal and slag, as in the case of copper and nickel converting. A now-uncommon form is batch treatment of pig iron to produce steel by the Bessemer process. The vessel used was called the Bessemer converter. Modern steel mills use basic oxygen process converters.
Polarizing organic photovoltaics Disadvantages Polarizing_organic_photovoltaics > Disadvantages This simply incorporates additional conversion efficiency losses. These devices harvest their own light. The article cited above, "Photovoltaics Could Charge A Phone Using Its Own Backlight" is bogus and makes claims that would violate the 1st and 2nd laws of thermodynamics if true. Such a device thus could not be patented and commercialized. See also: Perpetual Motion Machine
Phenylbutazone Side effects and disadvantages Phenylbutazone > Side effects and disadvantages Phenylbutazone amplifies the anticoagulant effect of vitamin K antagonists such as warfarin or phenprocoumon. Phenylbutazone displaces warfarin from plasma binding sites, and toxic blood levels leading to haemorrhage can occur. It may aggravate kidney or liver problems.
Morpheus (The Matrix) The Matrix Revolutions Morpheus_(The_Matrix) > Character history > The Matrix Revolutions When the Sentinels suddenly stop a second wave of attacks, Morpheus realizes that Neo is somehow fighting for them. When the Sentinels retreat after Neo defeats the former Agent Smith, now a virus that has threatened both humans and machines, Morpheus and Niobe embrace in celebration as cheers arise from the Zion population, who have received a brokered peace through Neo's sacrifice.
Robot Literature Robot > Robots in popular culture > Literature Later, Asimov added the Zeroth Law: "A robot may not harm humanity, or, by inaction, allow humanity to come to harm"; the rest of the laws are modified sequentially to acknowledge this. According to the Oxford English Dictionary, the first passage in Asimov's short story "Liar!" (1941) that mentions the First Law is the earliest recorded use of the word robotics. Asimov was not initially aware of this; he assumed the word already existed by analogy with mechanics, hydraulics, and other similar terms denoting branches of applied knowledge.
Classical capacity HSW theorem with the non-commutative union bound Classical_capacity > HSW theorem with the non-commutative union bound We now prove the HSW theorem with Sen's non-commutative union bound. We divide up the proof into a few parts: codebook generation, POVM construction, and error analysis. Codebook Generation. We first describe how Alice and Bob agree on a random choice of code.
Degree of reaction Further reading and works referred to Degree_of_reaction > Further reading and works referred to J. Mech. Sci., Kim, T. H., Takao, M., Setoguchi, T., Kaneko, K. and Inoue, M. (2001).
Miniaturized Satellites Technical challenges Small_satellite > Technical challenges Tiny satellites such as nanosats and small microsats may lack the power supply or mass for large conventional radio transponders, and various miniaturized or innovative communications systems have been proposed, such as laser receivers, antenna arrays and satellite-to-satellite communication networks. Few of these have been demonstrated in practice.
Causes of cancer pain Chemotherapy Causes_of_cancer_pain > Treatment-related > Chemotherapy Pain can often be helped with drug or other treatment but the numbness is usually resistant to treatment. A 2007 American study found that most patients did not recall being told to expect CIPN, and doctors monitoring the condition rarely asked how it affects daily living but focused on practical effects such as dexterity and gait.Mucositis Cancer drugs can cause changes in the biochemistry of mucous membranes resulting in intense pain in the mouth, throat, nasal passages, and gastrointestinal tract. This pain can make talking, drinking, or eating difficult or impossible.Muscle and joint pain Withdrawal of steroid medication can cause joint pain and diffuse muscle pain accompanied by fatigue; these symptoms resolve with recommencement of steroid therapy. Chronic steroid therapy can result in aseptic necrosis of the humoral or femoral head, resulting in shoulder or knee pain described as dull and aching, and reduced movement in or inability to use arm or hip. Aromatase inhibitors can cause diffuse muscle and joint pain and stiffness, and may increase the likelihood of osteoporosis and consequent fractures.
Matrix product Dot product, bilinear form and sesquilinear form Matrix–vector_product > Fundamental applications > Dot product, bilinear form and sesquilinear form The dot product of two column vectors is the unique entry of the matrix product x T y , {\displaystyle \mathbf {x} ^{\mathsf {T}}\mathbf {y} ,} where x T {\displaystyle \mathbf {x} ^{\mathsf {T}}} is the row vector obtained by transposing x {\displaystyle \mathbf {x} } . (As usual, a 1×1 matrix is identified with its unique entry.) More generally, any bilinear form over a vector space of finite dimension may be expressed as a matrix product x T A y , {\displaystyle \mathbf {x} ^{\mathsf {T}}\mathbf {Ay} ,} and any sesquilinear form may be expressed as x † A y , {\displaystyle \mathbf {x} ^{\dagger }\mathbf {Ay} ,} where x † {\displaystyle \mathbf {x} ^{\dagger }} denotes the conjugate transpose of x {\displaystyle \mathbf {x} } (conjugate of the transpose, or equivalently transpose of the conjugate).
Parallel resistors Electronic symbols and notation Resistors_in_parallel > Electronic symbols and notation Additional zeros imply a tighter tolerance, for example 15M0 for three significant digits. When the value can be expressed without the need for a prefix (that is, multiplicator 1), an "R" is used instead of the decimal separator. For example, 1R2 indicates 1.2 Ω, and 18R indicates 18 Ω.
Paranoid schizophrenic Differential diagnosis Paranoid_schizophrenic > Diagnosis > Differential diagnosis Schizophrenia occurs along with obsessive–compulsive disorder (OCD) considerably more often than could be explained by chance, although it can be difficult to distinguish obsessions that occur in OCD from the delusions of schizophrenia. There can be considerable overlap with the symptoms of post-traumatic stress disorder.A more general medical and neurological examination may be needed to rule out medical illnesses which may rarely produce psychotic schizophrenia-like symptoms, such as metabolic disturbance, systemic infection, syphilis, HIV-associated neurocognitive disorder, epilepsy, limbic encephalitis, and brain lesions. Stroke, multiple sclerosis, hyperthyroidism, hypothyroidism, and dementias such as Alzheimer's disease, Huntington's disease, frontotemporal dementia, and the Lewy body dementias may also be associated with schizophrenia-like psychotic symptoms.
Helix Bridge Permanent works Helix_Bridge > Construction > Permanent works A mobile gantry crane was positioned on the temporary bridge to lift elements into place. Erection started from the North Abutment starting with the horizontal prefabricated segments (av. 11m long). Then the horizontal deck components were bolted on, and then cross members, hoop members, tension rods, and other loose members were installed working upwards from deck level.
Critical angle (optics) Fresnel and the phase shift Frustrated_total_internal_reflection > History > Fresnel and the phase shift (19) and (20), above) by modeling light waves as transverse elastic waves with vibrations perpendicular to what had previously been called the plane of polarization. Using old experimental data, he promptly confirmed that the equations correctly predicted the direction of polarization of the reflected beam when the incident beam was polarized at 45° to the plane of incidence, for light incident from air onto glass or water. The experimental confirmation was reported in a "postscript" to the work in which Fresnel expounded his mature theory of chromatic polarization, introducing transverse waves.
Extensible Embeddable Language Example code Extensible_Embeddable_Language > Example code The classic hello world program can be written as follows: export function main { print("Hello, world!\n"); return 0; } The following is an example of a recursive function: export function main { print("Recursion test 1:\n"); procedure recurse(arg) { print("arg = ", arg, "\n"); if arg recurse(arg - 1); } recurse(10); print("Recursion test 2; Mutual Recursion:\n"); procedure mrecurse2(arg); procedure mrecurse1(arg) { print("arg = ", arg, "\n"); if arg mrecurse2(arg); } procedure mrecurse2(arg) { mrecurse1(arg - 1); }; mrecurse1(10); print("Recursion test 2; Mutual Recursion with Function Reference:\n"); procedure mrrecurse1(arg, fn) { print("arg = ", arg, "\n"); if arg fn(arg, fn); } local mrr2 = procedure (arg, fn) { mrrecurse1(arg - 1, fn); }; mrrecurse1(10, mrr2); print(Recursion tests done.\n); return 0; }
Fluorescence correlation spectroscopy The measurement volume Fluorescence_correlation_spectroscopy > The measurement volume The measurement volume is a convolution of illumination (excitation) and detection geometries, which result from the optical elements involved. The resulting volume is described mathematically by the point spread function (or PSF), it is essentially the image of a point source. The PSF is often described as an ellipsoid (with unsharp boundaries) of few hundred nanometers in focus diameter, and almost one micrometer along the optical axis. The shape varies significantly (and has a large impact on the resulting FCS curves) depending on the quality of the optical elements (it is crucial to avoid astigmatism and to check the real shape of the PSF on the instrument).
Singular simplicial complex C Normalized_chain_complex > C Explicitly, to each vector bundle E we assign a cohomology class, say, c(E). The assignment is natural in the sense that ƒc(E) = c(ƒE). chromatic homotopy theory chromatic homotopy theory.
Signature Record Type Definition Summary Signature_Record_Type_Definition Without some level of integrity protection an adversary could launch a phishing attack. Signing the NDEF record protects the integrity of the contents and allows the user to identify the signer if they wish. Signing certificates are obtained from third party Certificate Authorities and are governed by the NFC Forum Signature RTD Certificate Policy.
Distributed Computing Applications Distributed_processing > Applications Reasons for using distributed systems and distributed computing may include: The very nature of an application may require the use of a communication network that connects several computers: for example, data produced in one physical location and required in another location. There are many cases in which the use of a single computer would be possible in principle, but the use of a distributed system is beneficial for practical reasons. For example: It can allow for much larger storage and memory, faster compute, and higher bandwidth than a single machine.
Plandemic Fact-checking responses Plandemic > Plandemic: The Hidden Agenda Behind Covid-19 > Summary > Fact-checking responses This statement originates in work by Didier Raoult that subsequently received a "statement of concern" from the editors of the scientific journal in which it was published. The first randomized controlled trial to evaluate the efficacy of hydroxychloroquine for the treatment of COVID-19 found no evidence of benefit and some evidence of harm. The NIH said there is insufficient evidence to recommend for or against its use to treat COVID-19.
Diabetic hypoglycemia Brain desensitization to hypoglycemia Diabetic_hypoglycemia > Unawareness > Brain desensitization to hypoglycemia If a person has frequent episodes of hypoglycemia (even mild ones), the brain becomes "used to" the low glucose and no longer signals for epinephrine to be released during such times. More specifically, there are glucose transporters located in the brain cells (neurons). These transporters increase in number in response to repeated hypoglycemia (this permits the brain to receive a steady supply of glucose even during hypoglycemia).
Life-time of correlation Summary Life-time_of_correlation In probability theory and related fields, the life-time of correlation measures the timespan over which there is appreciable autocorrelation or cross-correlation in stochastic processes.
Hib vaccine Conjugate vaccine Hib_vaccine > Mechanisms of action > Conjugate vaccine PRP covalently linked to a protein carrier was found to elicit a greater immune response than the polysaccharide form of the vaccine. This is due to the protein carrier being highly immunogenic in nature. The conjugate formulations show responses which are consistent with T-cell recruitment (namely a much stronger immune response). A memory effect (priming of the immune system against future attack by Hib) is also observed after administration; indicative that memory B cell formation is also improved over that of the unconjugated polysaccharide form. Since optimal contact between B cells and T cells is required (via MHC II) to maximize antibody production, it is reasoned that the conjugate vaccine allows B cells to properly recruit T cells, this is in contrast to the polysaccharide form in which it is speculated that B cells do not interact optimally with T cells leading to the TI interaction.
Coupling capacitor potential device Types of Voltage Transformers Capacitor_voltage_transformer > Types of Voltage Transformers There are three primary types of potential transformers (PT): electromagnetic, capacitor, and optical. The electromagnetic potential transformer is a wire-wound transformer. The capacitor voltage transformer (CVT) uses a capacitance potential divider and is used at higher voltages due to a lower cost than an electromagnetic PT. An optical voltage transformer exploits the Faraday effect, rotating polarized light, in optical materials.
Thyroid binding globulin Role in diagnosis Thyroxine_binding_globulin > Role in diagnosis However, if total thyroid hormone levels point to hypothyroidism or hyperthyroidism in the absence of accompanying symptoms, the utility of TBG testing becomes more evident, since TBG production can be modified by other factors such as estrogen levels, corticosteroid levels, or liver failure. If, for example, the TBG level is high, which can occur when estrogen levels are high, the TBG will bind more thyroid hormone, decreasing the free hormone available in the blood, which leads to stimulation of TSH, and the production of more thyroid hormone. In this case, the total thyroid hormone level will be high.
Hydrogen acetate Organic chemistry Ethanoic_acid > Reactions > Organic chemistry Reduction of acetic acid gives ethanol. The OH group is the main site of reaction, as illustrated by the conversion of acetic acid to acetyl chloride. Other substitution derivatives include acetic anhydride; this anhydride is produced by loss of water from two molecules of acetic acid. Esters of acetic acid can likewise be formed via Fischer esterification, and amides can be formed. When heated above 440 °C (824 °F), acetic acid decomposes to produce carbon dioxide and methane, or to produce ketene and water: CH3COOH → CH4 + CO2 CH3COOH → CH2=C=O + H2O
Scale free network Overview Scale_free_network > Overview There are two major components that explain the emergence of the scale-free property in complex networks: the growth and the preferential attachment. By "growth" is meant a growth process where, over an extended period of time, new nodes join an already existing system, a network (like the World Wide Web which has grown by billions of web pages over 10 years). Finally, by "preferential attachment" is meant that new nodes prefer to connect to nodes that already have a high number of links with others. Thus, there is a higher probability that more and more nodes will link themselves to that one which has already many links, leading this node to a hub in-fine.
Conversion of units of energy Radiation – exposure List_of_conversion_factors > Radiation > Radiation – exposure The roentgen is not an SI unit and the NIST strongly discourages its continued use.
Network formation game Agent-based models Network_formation > Agent-based models The method tests the hypothesis that, given some initial setting and parameter values, a certain network structure will emerge as an equilibrium of this game. Since the number of nodes usually fixed, they can very rarely explain the properties of huge real-world networks; however, they are very useful to examine the network formation in smaller groups. Jackson and Wolinsky pioneered these types of models in a 1996 paper, which has since inspired several game-theoretic models. These models were further developed by Jackson and Watts, who put this approach to a dynamic setting to see how the network structure evolve over time.Usually, games with known network structure are widely applicable; however, there are various settings when players interact without fully knowing who their neighbors are and what the network structure is. These games can be modeled using incomplete information network games.
Hammerhead ribozyme Summary Hammerhead_ribozyme The hammerhead ribozyme is an RNA motif that catalyzes reversible cleavage and ligation reactions at a specific site within an RNA molecule. It is one of several catalytic RNAs (ribozymes) known to occur in nature. It serves as a model system for research on the structure and properties of RNA, and is used for targeted RNA cleavage experiments, some with proposed therapeutic applications. Named for the resemblance of early secondary structure diagrams to a hammerhead shark, hammerhead ribozymes were originally discovered in two classes of plant virus-like RNAs: satellite RNAs and viroids.
Glossary of environmental science R Glossary_of_environmental_science > R According to the language of the Kyoto Protocol, for the first commitment period (2008–2012), reforestation activities are limited to reforestation occurring on lands that did not contain forest at the start of 1990; replanting of forests on lands that have recently been harvested. regulating services – (sustainability) the benefits obtained from the regulation of ecosystem processes including, for example, the regulation of climate, water or disease. renewable energy - any source of energy that can be used without depleting its reserves.
Copiotroph Lifestyle Copiotroph > Lifestyle However, if it senses that the concentration gradient is decreasing they stop and choose another random direction to travel in.Another strategy includes the “run and reverse” in which the organism runs towards a nutrient. If it notices the gradient decreasing, it moves back to where the gradient is larger and heads in another direction from this new position.Through their motility and chemotaxis, copiotrophic microbes respond quickly to nutrients in their environment. With the help of these mechanisms, copiotrophs can travel to and stay in nutrient dense areas long enough for transcriptional regulatory systems to increase gene expression. This in turn helps them increase metabolic processes in high nutrient areas allowing them to maximize their growth during these patches.
Bijection Definition Partial_bijection > Definition For a pairing between X and Y (where Y need not be different from X) to be a bijection, four properties must hold: each element of X must be paired with at least one element of Y, no element of X may be paired with more than one element of Y, each element of Y must be paired with at least one element of X, and no element of Y may be paired with more than one element of X.Satisfying properties (1) and (2) means that a pairing is a function with domain X. It is more common to see properties (1) and (2) written as a single statement: Every element of X is paired with exactly one element of Y. Functions which satisfy property (3) are said to be "onto Y " and are called surjections (or surjective functions). Functions which satisfy property (4) are said to be "one-to-one functions" and are called injections (or injective functions). With this terminology, a bijection is a function which is both a surjection and an injection, or using other words, a bijection is a function which is both "one-to-one" and "onto".Bijections are sometimes denoted by a two-headed rightwards arrow with tail (U+2916 ⤖ RIGHTWARDS TWO-HEADED ARROW WITH TAIL), as in f: X ⤖ Y. This symbol is a combination of the two-headed rightwards arrow (U+21A0 ↠ RIGHTWARDS TWO HEADED ARROW), sometimes used to denote surjections, and the rightwards arrow with a barbed tail (U+21A3 ↣ RIGHTWARDS ARROW WITH TAIL), sometimes used to denote injections.
Decidable problem Decidability Decision_problems > Decidability A decision problem is decidable or effectively solvable if the set of inputs (or natural numbers) for which the answer is yes is a recursive set. A problem is partially decidable, semidecidable, solvable, or provable if the set of inputs (or natural numbers) for which the answer is yes is a recursively enumerable set. Problems that are not decidable are undecidable. For those it is not possible to create an algorithm, efficient or otherwise, that solves them. The halting problem is an important undecidable decision problem; for more examples, see list of undecidable problems.
Cartesian tensor Second-order tensors in three dimensions Cartesian_tensor > Cartesian basis and related terminology > Second-order tensors in three dimensions When vectors and tensors are written without reference to components, and indices are not used, sometimes a dot ⋅ is placed where summations over indices (known as tensor contractions) are taken. For the above cases: motivated by the dot product notation: More generally, a tensor of order m which takes in n vectors (where n is between 0 and m inclusive) will return a tensor of order m − n, see Tensor § As multilinear maps for further generalizations and details. The concepts above also apply to pseudovectors in the same way as for vectors. The vectors and tensors themselves can vary within throughout space, in which case we have vector fields and tensor fields, and can also depend on time. Following are some examples: For the electrical conduction example, the index and matrix notations would be: while for the rotational kinetic energy T: See also constitutive equation for more specialized examples.
Intergenic spacer Summary Intergenic_spacer In animals, the mitochondrial DNA genes generally have very short spacers. In fungi, mitochondrial DNA spacers are common and variable in length, and they may also be mobile.Due to the non-coding nature of spacer DNA, its nucleotide sequence changes much more rapidly over time than nucleotide sequences coding for genes that are subject to selective forces. Although spacer DNA might not have a function that depends on its nucleotide sequence, it may have sequence-independent functions.Spacer DNA has practical applications that enable researchers and scientists to examine interactions between CRISPR proteins and bacteriophages.
Mathematical models in physics Classifications Dynamic_model > Classifications Mathematical models are of different types: Linear vs. nonlinear: If all the operators in a mathematical model exhibit linearity, the resulting mathematical model is defined as linear. A model is considered to be nonlinear otherwise. The definition of linearity and nonlinearity is dependent on context, and linear models may have nonlinear expressions in them. For example, in a statistical linear model, it is assumed that a relationship is linear in the parameters, but it may be nonlinear in the predictor variables.
Nuisance variable Summary Nuisance_variable In the theory of stochastic processes in probability theory and statistics, a nuisance variable is a random variable that is fundamental to the probabilistic model, but that is of no particular interest in itself or is no longer of any interest: one such usage arises for the Chapman–Kolmogorov equation. For example, a model for a stochastic process may be defined conceptually using intermediate variables that are not observed in practice. If the problem is to derive the theoretical properties, such as the mean, variance and covariances of quantities that would be observed, then the intermediate variables are nuisance variables.The related term nuisance factor has been used in the context of block experiments, where the terms in the model representing block-means, often called "factors", are of no interest. Many approaches to the analysis of such experiments, particularly where the experimental design is subject to randomization, treat these factors as random variables.
Demis Hassabis DeepMind Demis_Hassabis > Career and research > DeepMind Hassabis has predicted that Artificial Intelligence will be "one of the most beneficial technologies of mankind ever" but that significant ethical issues remain.In 2023, Hassabis signed the statement that "Mitigating the risk of extinction from AI should be a global priority alongside other societal-scale risks such as pandemics and nuclear war". He considers however that a pause on AI progress would be very hard to enforce worldwide, and that the potential benefits (e.g. for health and against climate change) make it worth continuing. He said that there is an urgent need for research on evaluation tests that measure how capable and controllable new AI models are.
Hard realtime Criteria for real-time computing Near_real-time > Criteria for real-time computing Even though a pacemaker's task is simple, because of the potential risk to human life, medical systems like these are typically required to undergo thorough testing and certification, which in turn requires hard real-time computing in order to offer provable guarantees that a failure is unlikely or impossible. Industrial process controllers, such as a machine on an assembly line. If the machine is delayed, the item on the assembly line could pass beyond the reach of the machine (leaving the product untouched), or the machine or the product could be damaged by activating the robot at the wrong time.
Kernel methods for vector output Intrinsic coregionalization model (ICM) Kernel_methods_for_vector_output > Example kernels > Separable > From Bayesian literature > Intrinsic coregionalization model (ICM) In this case, the coefficients v d , d ′ = ∑ i = 1 R 1 a d , 1 i a d ′ , 1 i = b d , d ′ 1 {\displaystyle v_{d,d'}=\sum _{i=1}^{R_{1}}{a_{d,1}^{i}a_{d',1}^{i}}=b_{d,d'}^{1}} and the kernel matrix for multiple outputs becomes K ( x , x ′ ) = k ( x , x ′ ) B {\displaystyle \mathbf {K} (\mathbf {x} ,\mathbf {x} ')=k(\mathbf {x} ,\mathbf {x} ')\mathbf {B} } . ICM is much more restrictive than the LMC since it assumes that each basic covariance k q ( x , x ′ ) {\displaystyle k_{q}(\mathbf {x} ,\mathbf {x} ')} contributes equally to the construction of the autocovariances and cross covariances for the outputs. However, the computations required for the inference are greatly simplified.
Norepinephrine Stress Norepinephrine > Diseases and disorders > Stress Chronic stress, if continued for a long time, can damage many parts of the body. A significant part of the damage is due to the effects of sustained norepinephrine release, because of norepinephrine's general function of directing resources away from maintenance, regeneration, and reproduction, and toward systems that are required for active movement. The consequences can include slowing of growth (in children), sleeplessness, loss of libido, gastrointestinal problems, impaired disease resistance, slower rates of injury healing, depression, and increased vulnerability to addiction.
Memantine Adverse effects Memantine > Adverse effects Memantine is, in general, well tolerated. Common adverse drug reactions (≥1% of people) include confusion, dizziness, drowsiness, headache, insomnia, agitation, and/or hallucinations. Less common adverse effects include vomiting, anxiety, hypertonia, cystitis, and increased libido.Like many other NMDA antagonists, memantine behaves as a dissociative anesthetic at supratherapeutic doses. Despite isolated reports, recreational use of memantine is rare due to the drug's long duration and limited availability. Also memantine seems to lack effects such as euphoria or hallucinations.Memantine appears to be generally well tolerated by children with autism spectrum disorder.
Mode (user interface) Quasimodes Mode_(user_interface) > Design recommendations > Quasimodes In the book The Humane Interface, Jef Raskin championed what he termed quasimodes, which are modes that are kept in place only through some constant action on the part of the user; such modes are also called spring-loaded modes. The term quasimode is a composite of the Latin prefix quasi- (which means almost, to some degree) and the English word "mode". Modifier keys on the keyboard, such as the Shift key, the Alt key and the Control key, are all examples of a quasimodal interface. The application enters into that mode as long as the user is performing a conscious action, like pressing a key and keeping it pressed while invoking a command.
Beckmann rearrangement Reaction mechanism Beckmann_rearrangement > Reaction mechanism In the transition state leading to the iminium ion (σ-complex), the methyl group migrates to the nitrogen atom in a concerted reaction as the hydroxyl group is expelled. The oxygen atom in the hydroxyl group is stabilized by three acetic acid molecules. In the next step the electrophilic carbon atom in the nitrilium ion is attacked by water and a proton is donated back to acetic acid.
Allergic to penicillin Broad-spectrum antibiotics Penicillin-class_antibacterial > Types > Antibiotics created from 6-APA > Broad-spectrum antibiotics This group of antibiotics is called "broad-spectrum" because they are active against a wide range of Gram-negative bacteria such as Escherichia coli and Salmonella typhi, for which penicillin is not suitable. However, resistance in these organisms is now common. Ampicillin AmoxicillinThere are many ampicillin precursors in existence. These are inactive compounds that are broken down in the gut to release ampicillin. None of these pro-drugs of ampicillin are in current use: Pivampicillin (pivaloyloxymethyl ester of ampicillin) Bacampicillin Metampicillin (formaldehyde ester of ampicillin) Talampicillin Hetacillin (ampicillin conjugated to acetone)Epicillin is an aminopenicillin that has never seen widespread clinical use.
Point and figure chart How to draw Point_and_figure_chart > How to draw The correct way to draw a point and figure chart is to plot every price change but practicality has rendered this difficult to do for a large quantity of stocks so many point and figure chartists use the summary prices at the end of each day. Some prefer to use the day’s closing price and some prefer to use the day’s high or low depending on the direction of the last column. The high/low method was invented by A.W. Cohen in his 1947 book, 'How to Use the Three-Point Reversal Method of Point & Figure Stock Market Timing' and has a large following.
Quantum master equation Summary Quantum_master_equation A quantum master equation is a generalization of the idea of a master equation. Rather than just a system of differential equations for a set of probabilities (which only constitutes the diagonal elements of a density matrix), quantum master equations are differential equations for the entire density matrix, including off-diagonal elements. A density matrix with only diagonal elements can be modeled as a classical random process, therefore such an "ordinary" master equation is considered classical. Off-diagonal elements represent quantum coherence which is a physical characteristic that is intrinsically quantum mechanical.
Chemical Communications Summary Chemical_Communications ChemComm (or Chemical Communications), formerly known as Journal of the Chemical Society D: Chemical Communications (1969–1971), Journal of the Chemical Society, Chemical Communications (1972–1995), is a peer-reviewed scientific journal published by the Royal Society of Chemistry. It covers all aspects of chemistry. In January 2012, the journal moved to publishing 100 issues per year. The current chair of the editorial board is Douglas Stephan (University of Toronto, Canada), while the executive editor is Richard Kelly.
Hückel molecular orbital method Mathematics behind the Hückel method Hückel_method > Mathematics behind the Hückel method Thus, by minimizing E ( c 1 , … , c n ) = E {\displaystyle E(c_{1},\ldots ,c_{n})={\mathcal {E}}} with respect to coefficients c i {\displaystyle c_{i}} for normalized trial wavefunctions ψ g ( c 1 , … , c n ) {\displaystyle \psi _{g}(c_{1},\ldots ,c_{n})} , we obtain a closer approximation of the true ground-state wavefunction and its energy. To start, we apply the normalization condition to the ansatz and expand to get an expression for N in terms of the c i {\displaystyle c_{i}} . Then, we substitute the ansatz into the expression for E and expand, yielding E ( c 1 , … , c n ) = N 2 {\displaystyle E(c_{1},\ldots ,c_{n})=N^{2}{\Big }} , where N = − 1 / 2 {\displaystyle N={\Big }^{-1/2}} , S i j = ⟨ ϕ i \| ϕ j ⟩ = ∫ R 3 ϕ i ∗ ϕ j d V {\displaystyle S_{ij}=\langle \phi _{i}\|\phi _{j}\rangle =\int _{\mathbb {R} ^{3}}\phi _{i}^{}\,\phi _{j}\,dV} , and H i j = ⟨ ϕ i \| H ^ \| ϕ j ⟩ = ∫ R 3 ϕ i ∗ H ^ ϕ j d V {\displaystyle H_{ij}=\langle \phi _{i}\|{\hat {H}}\|\phi _{j}\rangle =\int _{\mathbb {R} ^{3}}\phi _{i}^{}\,{\hat {H}}\phi _{j}\,dV} .In the remainder of the derivation, we will assume that the atomic orbitals are real.
M-tree k-NN queries M-tree > M-tree queries > k-NN queries k-nearest neighbor (k-NN) query takes the cardinality of the input set as an input parameter. For a given query object Q ∈ D and an integer k ≥ 1, the k-NN query NN(Q, k) selects the k indexed objects which have the shortest distance from Q, according to the distance function d.
Timeline of scientific discoveries Geometry and trigonometry Scientific_breakthrough > 500 AD – 1000 AD > Mathematics > Geometry and trigonometry 628 AD: Brahmagupta discovers Brahmagupta's formula, a generalization of Heron's formula to cyclic quadrilaterals.
Sternothyroid muscle Clinical significance Sternothyroid_muscle > Clinical significance The upward extension of a thyroid swelling (goitre) is prevented by the attachment of the sternothyroid to the thyroid cartilage. A goitre can therefore only grow to the front, back or middle but no higher.
Glossary of botanical terms P Dichotomous_branching > P photosynthesis Process by which energy from sunlight is used to convert carbon dioxide and water into simple sugars in cells containing chloroplasts. All plants, except certain parasites, can perform photosynthesis. phyllary Individual bract within an involucre or involucel.
Peer production Applications Peer_production > Applications The scale and high level of reliability of the Bitcoin service suggests that peer production can lead to very high quality outcomes. The longevity of the Bitcoin network and its adoption over time also suggests that peer production can be very transformative. This seems to be very puzzling for skeptics who have criticized peer production for some of its unreliable or mediocre outcomes.
RegulonDB Graphic display in RegulonDB RegulonDB > Definitions > Graphic display in RegulonDB The graphic display of an operon contains all the genes of its different transcription units, as well as all the regulatory elements involved in the transcription and regulation of those TUs. An operon is here conceived as a structural unit encompassing all genes and regulatory elements. An operon with several promoters located near each other may also have dual binding sites, indicating that such a site can activate one particular promoter, but repress a second one. In the same page, the collection of the different TUs is displayed below the operon.
Algorithmic cooling Reversible algorithmic cooling - basic compression subroutine Algorithmic_cooling > Reversible algorithmic cooling - basic compression subroutine The algorithm operates on an array of equally (and independently) biased qubits. After the algorithm transfers heat (and entropy) from some qubits to the others, the resulting qubits are rearranged in increasing order of bias. Then this array is divided into two sub-arrays: "cold" qubits (with bias exceeding a certain threshold chosen by the user) and "hot" qubits (with bias lower than that threshold). Only the "cold" qubits are used for further quantum computation.
Surface area Definition Surface_area > Definition More rigorously, if a surface S is a union of finitely many pieces S1, …, Sr which do not overlap except at their boundaries, then A ( S ) = A ( S 1 ) + ⋯ + A ( S r ) . {\displaystyle A(S)=A(S_{1})+\cdots +A(S_{r}).} Surface areas of flat polygonal shapes must agree with their geometrically defined area.
Monopoly price Dynamic Pricing for Monopolies Monopoly_pricing > Theoretical Considerations > Dynamic Pricing for Monopolies Both pricing schemes are argued to be effective under the assumptions that price adjustments are costless. Further studies by Rajan et al. (1993) have also concluded that a variable pricing scheme to be optimal for maximizing profits. Rajan argues that dynamic costs such as purchasing and carrying costs should lead to an increase in price. Additionally, He suggests goods that drop in value or decay should lead to a decrease in price as demand for said goods also decrease therefore the firm should drop the price as to maximize profits again and reclaim lost producer surplus.
Werner Heisenberg Göttingen, Copenhagen and Leipzig Werner_Heisenberg > Academic career > Göttingen, Copenhagen and Leipzig On 1 May 1926, Heisenberg began his appointment as a university lecturer and assistant to Bohr in Copenhagen. It was in Copenhagen, in 1927, that Heisenberg developed his uncertainty principle, while working on the mathematical foundations of quantum mechanics. On 23 February, Heisenberg wrote a letter to fellow physicist Wolfgang Pauli, in which he first described his new principle.
Nervous System Neural circuits and systems Human_nervous_system > Function > Neural circuits and systems Neurons were found to be capable of producing regular sequences of action potentials, or sequences of bursts, even in complete isolation. When intrinsically active neurons are connected to each other in complex circuits, the possibilities for generating intricate temporal patterns become far more extensive. A modern conception views the function of the nervous system partly in terms of stimulus-response chains, and partly in terms of intrinsically generated activity patterns—both types of activity interact with each other to generate the full repertoire of behavior.
Cerebellar cortex Principles Granular_layer_(cerebellum) > Function > Principles Thus, the cerebellar network receives a modest number of inputs, processes them very extensively through its rigorously structured internal network, and sends out the results via a very limited number of output cells. Modularity: The cerebellar system is functionally divided into more or less independent modules, which probably number in the hundreds to thousands. All modules have a similar internal structure, but different inputs and outputs.
Public encryption key Hybrid cryptosystems Asymmetric_key > Applications > Hybrid cryptosystems Because asymmetric key algorithms are nearly always much more computationally intensive than symmetric ones, it is common to use a public/private asymmetric key-exchange algorithm to encrypt and exchange a symmetric key, which is then used by symmetric-key cryptography to transmit data using the now-shared symmetric key for a symmetric key encryption algorithm. PGP, SSH, and the SSL/TLS family of schemes use this procedure; they are thus called hybrid cryptosystems. The initial asymmetric cryptography-based key exchange to share a server-generated symmetric key from the server to client has the advantage of not requiring that a symmetric key be pre-shared manually, such as on printed paper or discs transported by a courier, while providing the higher data throughput of symmetric key cryptography over asymmetric key cryptography for the remainder of the shared connection.
Finite model theory Querying and search Finite_model_theory > Applications > Querying and search Narrative data contains no defined relations. Thus the logical structure of text search queries can be expressed in propositional logic, like in: ("Java" AND NOT "island") OR ("C#" AND NOT "music") Note that the challenges in full text search are different from database querying, like ranking of results.
Stacked paper capacitor Electrolytic capacitors Practical_capacitors > Types and styles > Electrolytic capacitors Three general types of electrolytes are used: non solid (wet, liquid)—conductivity approximately 10 mS/cm and are the lowest cost solid manganese oxide—conductivity approximately 100 mS/cm offer high quality and stability solid conductive polymer (Polypyrrole or PEDOT:PSS)—conductivity approximately 100...500 S/cm, offer ESR values as low as <10 mΩInternal losses of electrolytic capacitors, prevailing used for decoupling and buffering applications, are determined by the kind of electrolyte. The large capacitance per unit volume of electrolytic capacitors make them valuable in relatively high-current and low-frequency electrical circuits, e.g. in power supply filters for decoupling unwanted AC components from DC power connections or as coupling capacitors in audio amplifiers, for passing or bypassing low-frequency signals and storing large amounts of energy. The relatively high capacitance value of an electrolytic capacitor combined with the very low ESR of the polymer electrolyte of polymer capacitors, especially in SMD styles, makes them a competitor to MLC chip capacitors in personal computer power supplies.
Incompressibility method Turing-machine time complexity Incompressibility_method > Applications > Turing-machine time complexity The basic Turing machine, as conceived by Alan Turing in 1936, consists of a memory: a tape of potentially-infinite cells on which a symbol can be written and a finite control, with a read-write head attached, which scans a cell on the tape. At each step, the read-write head can change the symbol in the cell being scanned and move one cell left, right, or not at all according to instruction from the finite control. Turing machines with two tape symbols may be considered for convenience, but this is not essential.
Glossary of cell biology D Glossary_of_cell_biology > D developmental biology diakinesis In meiosis, the fifth and final substage of prophase I, following diplonema and preceding metaphase I. During diakinesis, the chromosomes are further condensed, the two centrosomes reach opposite poles of the cell, and the spindle apparatus begins to extend from the poles to the equator. diplonema Also diplotene stage. In meiosis, the fourth of the five substages of prophase I, following pachynema and preceding diakinesis. During diplonema, the synaptonemal complex disassembles and the paired homologous chromosomes begin to separate from one another, though they remain tightly bound at the chiasmata where chromosomal crossover has occurred. DNA See deoxyribonucleic acid.

Subsets and Splits

No community queries yet

The top public SQL queries from the community will appear here once available.