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Energy efficiency in transportation Automobiles Energy_efficiency_in_transportation > Land transport means > Automobiles Automobiles are generally inefficient when compared to other modes of transport, due to the relatively high weight of the vehicle compared to its occupants. Automobile fuel efficiency is most commonly expressed in terms of the volume of fuel consumed per one hundred kilometres (l/100 km), but in some countries (including the United States, the United Kingdom and India) it is more commonly expressed in terms of the distance per volume fuel consumed (km/L or miles per gallon). This is complicated by the different energy content of fuels such as petrol and diesel. The Oak Ridge National Laboratory (ORNL) states that the energy content of unleaded petrol is 115,000 British thermal unit (BTU) per US gallon (32 MJ/L) compared to 130,500 BTU per US gallon (36.4 MJ/L) for diesel.Due to the efficiency of electric motors, electric cars are much more efficient than their internal combustion engine counterparts, consuming on the order of 38 megajoules (38 000 kJ) per 100 km in comparison to 142 megajoules per 100 km for combustion powered cars. |
Applied category theory Summary Applied_category_theory Applied category theory is an academic discipline in which methods from category theory are used to study other fields including but not limited to computer science, physics (in particular quantum mechanics), natural language processing, control theory, probability theory and causality. The application of category theory in these domains can take different forms. In some cases the formalization of the domain into the language of category theory is the goal, the idea here being that this would elucidate the important structure and properties of the domain. In other cases the formalization is used to leverage the power of abstraction in order to prove new results about the field. |
Indole acetic acid Bacterial physiology Indoleacetic_acid > Biological effects > Bacterial physiology IAA production is widespread among environmental bacteria that inhabit soils, waters, but also plant and animal hosts. Distribution and substrate specificity of the involved enzymes suggests these pathways play a role beyond plant-microbe interactions. Enterobacter cloacae can produce IAA, from aromatic and branched-chain amino acids. |
OS kernel Monolithic kernels vs. microkernels Kernel_image > Kernel-wide design approaches > Monolithic kernels vs. microkernels As the computer kernel grows, so grows the size and vulnerability of its trusted computing base; and, besides reducing security, there is the problem of enlarging the memory footprint. This is mitigated to some degree by perfecting the virtual memory system, but not all computer architectures have virtual memory support. To reduce the kernel's footprint, extensive editing has to be performed to carefully remove unneeded code, which can be very difficult with non-obvious interdependencies between parts of a kernel with millions of lines of code. |
Cardiac imaging Echocardiography Cardiac_imaging > Echocardiography Echocardiography is regularly utilized to diagnose, manage, and monitor patients with suspected or established heart ailments, making it a highly prevalent diagnostic imaging technique in cardiology due to its speed and efficiency. |
Synthetic biological circuits Controllers of gene expression heterogeneity Synthetic_biological_circuits > Example circuits > Controllers of gene expression heterogeneity Synthetic gene circuits can control gene expression heterogeneity can be controlled independently of the gene expression mean. |
VHF Omnidirectional Range DVOR VHF_Omnidirectional_Range > Technical specification > DVOR The doppler signal encodes the station identifier, i(t), optional voice, a(t), navigation variable signal in c(t), and the isotropic (i.e. omnidirectional) component. The navigation variable signal is A3 modulated (greyscale). The navigation reference signal is delayed, t+, t−, by electrically revolving a pair of transmitters. The cyclic doppler blue shift, and corresponding doppler red shift, as a transmitter closes on and recedes from the receiver results in F3 modulation (colour). |
Banach norm Spaces of continuous functions Banach_space > Some classification results > Spaces of continuous functions The Banach space C ( K ) {\displaystyle C(K)} is then isometric to C(⟨1, α⟩). When α , β {\displaystyle \alpha ,\beta } are two countably infinite ordinals, and assuming α ≤ β , {\displaystyle \alpha \leq \beta ,} the spaces C(⟨1, α⟩) and C(⟨1, β⟩) are isomorphic if and only if β < αω. For example, the Banach spaces are mutually non-isomorphic. |
Venous hypertension Signs and symptoms Chronic_venous_insufficiency > Signs and symptoms Malignancy, malignant degeneration being a rare but important complication of venous disease since tumors that develop in the setting of an ulcer tend to be more aggressive. Pain, a feature of venous disease often overlooked and commonly undertreated. Anxiety Depression Inflammation Cellulitis |
Toyota U transmission U340E Toyota_U_transmission > U3xx > U340E 4 speed automatic transaxle Gear ratios for this transmission. Application: 2000–2005 Echo 2004–2006 SCION xA 2004–2006 SCION xB 2003 Corolla (1.5 L 1NZ-FE) 2002–2016 Vios (1.5 L 1NZ-FE) 2006–2012 Yaris (1.5 L 1NZ-FE) |
Computational Chemistry Chemical dynamics Computational_Chemistry > Methods > Chemical dynamics Once the electronic and nuclear variables are separated (within the Born–Oppenheimer representation), in the time-dependent approach, the wave packet corresponding to the nuclear degrees of freedom is propagated via the time evolution operator (physics) associated to the time-dependent Schrödinger equation (for the full molecular Hamiltonian). In the complementary energy-dependent approach, the time-independent Schrödinger equation is solved using the scattering theory formalism. The potential representing the interatomic interaction is given by the potential energy surfaces. In general, the potential energy surfaces are coupled via the vibronic coupling terms. The most popular methods for propagating the wave packet associated to the molecular geometry are: the split operator technique, the Chebyshev (real) polynomial, the multi-configuration time-dependent Hartree method (MCTDH), the semiclassical method. |
Zinin reaction Reaction mechanism Zinin_reaction > Reaction mechanism Many details of the reaction mechanism are obscure, but it is known that the reaction requires water. Thiosulfate is one product. A possible stoichiometry for the reaction is: 4 ArNO2 + 6 S2- + 7 H2O → 4 ArNH2 + 3 S2O32- + 6 OH-Mechanistic studies have shown that disulfide (which is likely to be generated in situ) is a more active reducing agent and may be involved. The reaction is believed to proceed through oxygen transfer to sulfur to give ArNO, followed by further reduction to ArNHOH and, finally, to ArNH2. |
Simple cycle Directed circuit and directed cycle Directed_cycle > Definitions > Directed circuit and directed cycle A directed circuit is a non-empty directed trail in which the first and last vertices are equal (closed directed trail).Let G = (V, E, ϕ) be a directed graph. A directed circuit is a non-empty directed trail (e1, e2, …, en) with a vertex sequence (v1, v2, …, vn, v1).A directed cycle or simple directed circuit is a directed circuit in which only the first and last vertices are equal. |
Holography Physics of holography Holographic_art > Physics of holography For a better understanding of the process, it is necessary to understand interference and diffraction. Interference occurs when one or more wavefronts are superimposed. Diffraction occurs when a wavefront encounters an object. |
Classifier system Terminology Classifier_system > Terminology Beyond this, some LCS algorithms, or closely related methods, have been referred to as 'cognitive systems', 'adaptive agents', 'production systems', or generically as a 'classifier system'. This variation in terminology contributes to some confusion in the field. Up until the 2000s nearly all learning classifier system methods were developed with reinforcement learning problems in mind. As a result, the term ‘learning classifier system’ was commonly defined as the combination of ‘trial-and-error’ reinforcement learning with the global search of a genetic algorithm. Interest in supervised learning applications, and even unsupervised learning have since broadened the use and definition of this term. |
History of mathematical notation Maxwell, Clifford, and Ricci notations History_of_mathematical_notation > Symbolic stage > High division operators and functions > Maxwell, Clifford, and Ricci notations In 1871 Richard Dedekind called a set of real or complex numbers which is closed under the four arithmetic operations a field. In 1873 Maxwell presented A Treatise on Electricity and Magnetism. In 1878, William Kingdon Clifford published his Elements of Dynamic. |
Control channel Summary Control_channel In radio communication, a control channel is a central channel that controls other constituent radios by handling data streams. It is most often used in the context of a trunked radio system, where the control channel sends various data which coordinates users in talkgroups. In GSM networks, Control Channels are divided into three categories: Broadcast Channel (BCH), Common Control Channel (CCCH), and Dedicated Control Channel (DCCH). |
Base (exponentiation) Related terms Base_(exponentiation) > Related terms He referred to a as a "constant number" in an extensive consideration of the function F(z) = az. First z is a positive integer, then negative, then a fraction, or rational number. : 155 |
Machine screw Differentiation between bolt and screw Machine_screw > Differentiation between bolt and screw Machinery's Handbook describes the distinction as follows: A bolt is an externally threaded fastener designed for insertion through holes in assembled parts, and is normally intended to be tightened or released by torquing a nut. A screw is an externally threaded fastener capable of being inserted into holes in assembled parts, of mating with a preformed internal thread or forming its own thread, and of being tightened or released by torquing the head. An externally threaded fastener which is prevented from being turned during assembly and which can be tightened or released only by torquing a nut is a bolt. |
Conventional transmission electron microscope Diffraction Conventional_transmission_electron_microscope > Imaging methods > Diffraction As previously stated, by adjusting the magnetic lenses such that the back focal plane of the lens rather than the imaging plane is placed on the imaging apparatus a diffraction pattern can be generated. For thin crystalline samples, this produces an image that consists of a pattern of dots in the case of a single crystal, or a series of rings in the case of a polycrystalline or amorphous solid material. For the single crystal case the diffraction pattern is dependent upon the orientation of the specimen and the structure of the sample illuminated by the electron beam. This image provides the investigator with information about the space group symmetries in the crystal and the crystal's orientation to the beam path. |
Methylated DNA immunoprecipitation Background Methylated_DNA_immunoprecipitation > Background DNA methylation, referring to the reversible methylation of the 5 position of cytosine by methyltransferases, is a major epigenetic modification in multicellular organisms. In mammals, this modification primarily occurs at CpG sites, which in turn tend to cluster in regions called CpG islands. There is a small fraction of CpG islands that can overlap or be in close proximity to promoter regions of transcription start sites. The modification may also occur at other sites, but methylation at either of these sites can repress gene expression by either interfering with the binding of transcription factors or modifying chromatin structure to a repressive state.Disease condition studies have largely fueled the effort in understanding the role of DNA methylation. |
History of calculus Leibniz History_of_calculus > Newton and Leibniz > Leibniz He was acutely aware of the notational terms used and his earlier plans to form a precise logical symbolism became evident. Eventually, Leibniz denoted the infinitesimal increments of abscissas and ordinates dx and dy, and the summation of infinitely many infinitesimally thin rectangles as a long s (∫ ), which became the present integral symbol ∫ {\displaystyle \scriptstyle \int } . While Leibniz's notation is used by modern mathematics, his logical base was different from our current one. |
Introduction to general relativity Sources of gravity Introduction_to_general_relativity > Geometry and gravitation > Sources of gravity In Newton's description of gravity, the gravitational force is caused by matter. More precisely, it is caused by a specific property of material objects: their mass. In Einstein's theory and related theories of gravitation, curvature at every point in spacetime is also caused by whatever matter is present. |
Force control General Force_control > General Controlling the contact force between a manipulator and its environment is an increasingly important task in the environment of mechanical manufacturing, as well as industrial and service robot. One motivation for the use of force control is safety for man and machine. For various reasons, movements of the robot or machine parts may be blocked by obstacles while the program is running. In service robot these can be moving objects or people, in industrial robotics problems can occur with cooperating robots, changing work environments or an inaccurate environmental model. |
Coordinative definition Formalism Coordinative_definition > Formalism This is very similar to, but distinct from an operational definition. The difference is that coordinative definitions do not necessarily define theoretical terms in terms of laboratory procedures or experimentation, as operationalism does, but may also define them in terms of observable or empirical entities. |
Experimental science History Experimental_research > History Antoine Lavoisier (1743–1794), a French chemist, used experiment to describe new areas, such as combustion and biochemistry and to develop the theory of conservation of mass (matter). Louis Pasteur (1822–1895) used the scientific method to disprove the prevailing theory of spontaneous generation and to develop the germ theory of disease. Because of the importance of controlling potentially confounding variables, the use of well-designed laboratory experiments is preferred when possible. A considerable amount of progress on the design and analysis of experiments occurred in the early 20th century, with contributions from statisticians such as Ronald Fisher (1890–1962), Jerzy Neyman (1894–1981), Oscar Kempthorne (1919–2000), Gertrude Mary Cox (1900–1978), and William Gemmell Cochran (1909–1980), among others. |
ZF 6HP transmission Preliminary Note ZF_6HP_transmission > Specifications > Preliminary Note All ZF 6HP gearboxes have the same gear ratios as the 6R60 and 6R80 gearboxes for passenger cars from Ford. Deviant gear ratios indicate another manufacturer as shown in the template. |
FK-space Definition FK-space > Definition A FK-space is a sequence space X {\displaystyle X} , that is a linear subspace of vector space of all complex valued sequences, equipped with the topology of pointwise convergence. We write the elements of X {\displaystyle X} as with x n ∈ C {\displaystyle x_{n}\in \mathbb {C} } . Then sequence ( a n ) n ∈ N ( k ) {\displaystyle \left(a_{n}\right)_{n\in \mathbb {N} }^{(k)}} in X {\displaystyle X} converges to some point ( x n ) n ∈ N {\displaystyle \left(x_{n}\right)_{n\in \mathbb {N} }} if it converges pointwise for each n . {\displaystyle n.} That is if for all n ∈ N , {\displaystyle n\in \mathbb {N} ,} |
153 (number) In the Bible 153_(number) > In the Bible Grant himself opined that "there is every reason to suppose" that in fact Jerome had not actually checked Oppian's writing directly for this information, but was rather recounting secondhand some earlier Christian commentary on the Gospel of John.Many other numerological interpretations have been propounded, from adding numerological representations of Simon's name to the Greek word for fish through the additions (100+50+7) of Cyril of Alexandria to the multiplications (17×3×3) of Gregory the Great.Frédéric Louis Godet characterized them as "strange". There were at least 18 distinct numerological explanations when John Emerton performed "a quick survey" in 1958. Emerton proceeded to then add a gematrial explanation, to which 8 others have been added since. |
Occupational science Summary Occupational_science Occupational science is a discipline dedicated to the study of humans as "doers" or "occupational beings". As used here, the term "occupation" refers to the intentional or goal-directed activities that characterize daily human life as well as the characteristics and patterns of purposeful activity that occur over lifetimes. |
Prosthetic devices Feedback Prosthetic_hand > Current technology and manufacturing > Body-powered arms > Feedback An additional difference exists in the biofeedback created that allows the user to "feel" what is being held. Voluntary opening systems once engaged provide the holding force so that they operate like a passive vice at the end of the arm. No gripping feedback is provided once the hook has closed around the object being held. |
Crofelemer Mechanism of action Crofelemer > Mechanism of action The drug is taken by orally and works by modulating cystic fibrosis transmembrane conductance regulator (CFTR) and the calcium-activated chloride channel (CaCC), two chloride ion channels from the luminal side of the gastrointestinal tract. This is a first-in-class antisecretory antidiarrheal mechanism of action and it does not affect gastrointestinal motility, unlike the traditional antimotility drugs. As a result of the channel regulation, fewer chloride ions are secreted into the gut, which decreases the associated secretion of sodium ions and accompanying water, thus improving stool consistency and reducing the frequency of watery stools and duration of the diarrhea. The mechanism is selective for the CFTR and CaCC, as other channels involved in intestinal fluid secretion, namely sodium and potassium channels, are not affected by crofelemer, nor is cAMP or calcium signaling.Crofelemer is minimally, if at all, absorbed from the gut into the bloodstream, and is mostly excreted in the stools. |
Inelastic good Applications Elasticity_(economics) > Applications Whilst a tax increase on inelastic goods will not impact their demand, it may affect goods that are elastic. Aside from taxation, elasticity can also assist in analysing the need for government intervention. Additionally, for essential goods, the government must ensure that they are available to most consumers. |
Comparison of system dynamics software Summary Comparison_of_system_dynamics_software This is a comparison of various aspects of software offering system dynamics features: Due to concerns over commercial postings on the system dynamics main topic, commercial hyperlinks are specifically NOT active on this list. |
Conversion as a service Goals Conversion_as_a_service > Key Characteristics > Goals There are three goals for clarity in Pay-For-Performance Models: Transparency Pay-for-performance models require a level of transparency on the part of the vendor to share with clients both the process for collecting the data and for measuring the results. Also, the calculations should be kept simple and the ability to inspect the data readily available.Alignment Organizations often use metrics to define success for groups and individuals, to guide their activities, and to grade their performance. Similarly, vendors should be committed to meet the business objectives of an organization through goals. In most pay-for-performance models, vendors define the metrics by which they will be graded. |
B-1 cell Types B1_cell > Types B1a derived cells have a subset named innate response activator(IRA) B cells. IRA B cells produce GM-CSF and IL-3. In atherosclerosis, they accumulate in spleen. This results in extramedullary hematopoiesis and activating dendritic cell. |
Object Database Overview Object_persistence > Overview Object-oriented database management systems (OODBMSs) also called ODBMS (Object Database Management System) combine database capabilities with object-oriented programming language capabilities. OODBMSs allow object-oriented programmers to develop the product, store them as objects, and replicate or modify existing objects to make new objects within the OODBMS. Because the database is integrated with the programming language, the programmer can maintain consistency within one environment, in that both the OODBMS and the programming language will use the same model of representation. Relational DBMS projects, by way of contrast, maintain a clearer division between the database model and the application. |
Recombination hotspots Meiotic recombination Recombination_hotspots > Meiotic recombination Meiotic recombination through crossing over is thought to be a mechanism by which a cell promotes correct segregation of homologous chromosomes and repair of DNA damages. Crossing over requires a DNA double-stranded break followed by strand invasion of the homolog and subsequent repair. Initiation sites for recombination are usually identified by mapping crossing over events through pedigree analysis or through analysis of linkage disequilibrium. Linkage disequilibrium has identified more than 30,000 hotspots within the human genome. In humans, the average number of crossover recombination events per hotspot is one crossover per 1,300 meioses, and the most extreme hotspot has a crossover frequency of one per 110 meioses. |
Trading halt Regulatory and non-regulatory trading halts Trading_halt > Regulatory and non-regulatory trading halts Both of the reasons mentioned above are "regulatory" trading halts and are implemented on many major stock exchanges (for example, the NYSE American, NASDAQ, and New York Stock Exchange). When a United States exchange enacts a regulatory halt for a security, other U.S. exchanges that also trade the security will honor the halt.The NASDAQ and other exchanges currently use 11 codes to specify in more detail why trading has been halted for a security. The Over The Counter Bulletin Board (OTCBB) currently uses 5 codes.A "non-regulatory" trading halt occurs if "significant order imbalance between buyers and sellers in a security" exist. |
Dominique de Caen Academic research Dominique_de_Caen > Academic research "Stellar permutations of the two‐element subsets of a finite set". Journal of Combinatorial Designs. 6 (5): 381–387. |
Gene control Regulated stages of gene expression Gene_activation > Regulated stages of gene expression Any step of gene expression may be modulated, from signaling to transcription to post-translational modification of a protein. The following is a list of stages where gene expression is regulated, where the most extensively utilized point is transcription initiation, the first stage in transcription: Signal transduction Chromatin, chromatin remodeling, chromatin domains Transcription Post-transcriptional modification RNA transport Translation mRNA degradation |
Bacterial DNA Elongation Circular_bacterial_chromosome > Replication > Elongation DNA Pol III uses one set of its core subunits to synthesize the leading strand continuously, while the other set of core subunits cycles from one Okazaki fragment to the next on the looped lagging strand. Leading strand synthesis begins with the synthesis of a short RNA primer at the replication origin by the enzyme Primase (DnaG protein). Deoxynucleotides are then added to this primer by a single DNA polymerase III dimer, in an integrated complex with DnaB helicase. |
Table sharing Summary Table_sharing Table sharing is the practice of seating multiple separate parties (individual customers or groups of customers) who may not know each other at a single restaurant table. |
Wind Measurement Wind > Measurement A short burst of high speed wind is termed a wind gust, one technical definition of a wind gust is: the maxima that exceed the lowest wind speed measured during a ten-minute time interval by 10 knots (5 m/s) for periods of seconds. A squall is an increase of the wind speed above a certain threshold, which lasts for a minute or more. |
Cryptographic hash Wide pipe versus narrow pipe Hash_function_(cryptography) > Hash function design > Wide pipe versus narrow pipe A straightforward application of the Merkle–Damgård construction, where the size of hash output is equal to the internal state size (between each compression step), results in a narrow-pipe hash design. This design causes many inherent flaws, including length-extension, multicollisions, long message attacks, generate-and-paste attacks, and also cannot be parallelized. As a result, modern hash functions are built on wide-pipe constructions that have a larger internal state size – which range from tweaks of the Merkle–Damgård construction to new constructions such as the sponge construction and HAIFA construction. None of the entrants in the NIST hash function competition use a classical Merkle–Damgård construction.Meanwhile, truncating the output of a longer hash, such as used in SHA-512/256, also defeats many of these attacks. |
CpG site Methylation of CpG islands stably silences genes CpG_dinucleotide > Methylation, silencing, cancer, and aging > Methylation of CpG islands stably silences genes In humans, DNA methylation occurs at the 5 position of the pyrimidine ring of the cytosine residues within CpG sites to form 5-methylcytosines. The presence of multiple methylated CpG sites in CpG islands of promoters causes stable silencing of genes. Silencing of a gene may be initiated by other mechanisms, but this is often followed by methylation of CpG sites in the promoter CpG island to cause the stable silencing of the gene. |
Cohomology Axioms and generalized cohomology theories Cohomology > Axioms and generalized cohomology theories There are various ways to define cohomology for topological spaces (such as singular cohomology, Čech cohomology, Alexander–Spanier cohomology or sheaf cohomology). (Here sheaf cohomology is considered only with coefficients in a constant sheaf.) These theories give different answers for some spaces, but there is a large class of spaces on which they all agree. This is most easily understood axiomatically: there is a list of properties known as the Eilenberg–Steenrod axioms, and any two constructions that share those properties will agree at least on all CW complexes. |
R4000 Memory management R4000 > Description > Memory management The memory management unit (MMU) uses a 48-entry translation lookaside buffer to translate virtual addresses. The R4000 uses a 64-bit virtual address, but only implements 40 of the 64 bits, allowing 1 TB of virtual memory; the remaining bits are checked to ensure that they contain zero. The R4000 uses a 36-bit physical address, thus is able to address 64 GB of physical memory. |
Test management Generating reports and metrics Test_management > Generating reports and metrics The ultimate goal of test management tools is to deliver sensitive metrics that will help the QA manager in evaluating the quality of the system under test before releasing. Metrics are generally presented as graphics and tables indicating success rates, progression/regression and much other sensitive data. |
Noise calculation Data capture Noise_calculation > Data capture NoiseScore is a mobile app for crowdsourcing community noise. |
Aryl hydrocarbon receptor repressor Function Aryl_hydrocarbon_receptor_repressor > Function Dioxins and dioxin-like compounds are teratogens that exert their effects through the aryl hydrocarbon receptor (AhR) in conjunction with the receptor's binding partner, aryl hydrocarbon receptor nuclear translocator (ARNT). The protein encoded by this gene represses signal transduction by the AhR by competing with the arylhydrocarbon receptor for binding to the ARNT. Expression of the repressor is stimulated by the receptor/translocator heterodimer, thereby regulating receptor function through a negative feedback mechanism. In addition, the encoded protein can bind to nuclear factor-kappa B. The AhRR gene may act as a tumor suppressor. |
Industrial property Industrial designs Industrial_property > Industrial designs Industrial designs are applied to a wide variety of industrial products and handicrafts. They refer to the ornamental or aesthetic aspects of an article, including compositions of lines or colors or any three-dimensional forms that give a special appearance to a product or handicraft. The design must have aesthetic appeal. Moreover, it must be able to be reproduced by industrial means; this is the essential purpose of the design and the reason the design is called “industrial”. |
Hemoglobin Oxyhemoglobin Hemoglobin > Structure of heme > Oxygen saturation > Oxyhemoglobin Oxyhemoglobin is formed during physiological respiration when oxygen binds to the heme component of the protein hemoglobin in red blood cells. This process occurs in the pulmonary capillaries adjacent to the alveoli of the lungs. The oxygen then travels through the blood stream to be dropped off at cells where it is utilized as a terminal electron acceptor in the production of ATP by the process of oxidative phosphorylation. |
Off-target effects of genome editing Methods to increase specificity Off-target_effects_of_genome_editing > Improvements > Methods to increase specificity The widely used Streptococcus pyogenes Cas9 (SpCas9) nuclease is effective, however it induces unwanted off-target mutations at high frequencies. Several engineering and screening methods have been described in an effort to reduce genome-wide off-target mutations including nuclease mutation, protospacer adjacent motif (PAM) sequence modification, guide RNA (gRNA) truncation and novel nuclease discovery. For example, in 2013, Fu et al. reported that by truncating the gRNA from <20 bp in length to 17 or 18 bp the target specificity of the nuclease increased up to 5,000 fold and mismatch occurrences above 3 bases rarely, if ever occurred. |
Memory improvement Personal Application & Intellectual Conception Memory_improvement > Strategies > Personal Application & Intellectual Conception Testing effect occurs because of the development of an adequate retrieval structure. The testing effect is different from re-reading because the information being learned is being practiced and tested which forces the information to be drawn from memory to recall. The testing effect allows for information to be recalled over a longer period as it is used as a self-testing tool and aids in having the ability to recall information in the future. |
The long tail Statistical meaning Power-law_tail > Statistical meaning As a rule of thumb, for such population distributions the majority of occurrences (more than half, and where the Pareto principle applies, 80%) are accounted for by the first 20% of items in the distribution. Power law distributions or functions characterize an important number of behaviors from nature and human endeavor. This fact has given rise to a keen scientific and social interest in such distributions, and the relationships that create them. |
Bayesian optimization Summary Bayesian_optimization Bayesian optimization is a sequential design strategy for global optimization of black-box functions that does not assume any functional forms. It is usually employed to optimize expensive-to-evaluate functions. |
Chronic relapsing inflammatory optic neuritis Diagnosis Chronic_relapsing_inflammatory_optic_neuritis > Diagnosis ANA, indicative of autoimmune optic neuropathy, is also generally negative. CSF can also be evaluated for oligoclonal bands typical of multiple sclerosis, which will not be present in CRION. A chest X-ray or CT scan should be ordered if granulomatous optic neuropathy caused by sarcoidosis is suspected.Magnetic resonance imaging can capture optic nerve inflammation, but this finding is not present in all patients, Diffusion tensor imaging has been shown to detect widespread white matter abnormalities in CRION patients with normal MRI findings.Five diagnostic criteria had been proposed in 2014: History of optic neuritis with one relapse Objectively measured visual loss NMO-IgG seronegative Contrast enhancement on imaging of acutely inflamed optic nerves Response to immunosuppressive treatment and relapse on withdrawal or dose reduction.CRION has been included as a subtype in a 2022 international consensus classification of optic neuritis. |
Statistics Experimental and observational studies Applied_Statistics > Statistical data > Data collection > Experimental and observational studies Each can be very effective. An experimental study involves taking measurements of the system under study, manipulating the system, and then taking additional measurements using the same procedure to determine if the manipulation has modified the values of the measurements. |
Scale co-occurrence matrix Summary Scale_co-occurrence_matrix One basis of the method is the fact: way texture information changes from one scale to another can represent that texture in some extent thus it can be used as a criterion for feature extraction. The matrix captures the relation of features between different scales rather than the features within a single scale space, which can represent the scale property of texture better. Also, there are several experiments showing that it can get more accurate results for texture classification than the traditional texture classification. |
Complex harmonic motion Introduction Complex_harmonic_motion > Types > Damped harmonic motion > Introduction Specifically, when an object is damping, the damping force F {\displaystyle F} will be related to velocity v {\displaystyle v} by a coefficient c {\displaystyle c}: F = − c v . {\displaystyle F=-cv.} |
Methods of integration Symbolic Definite_Integrals > Computation > Symbolic Many problems in mathematics, physics, and engineering involve integration where an explicit formula for the integral is desired. Extensive tables of integrals have been compiled and published over the years for this purpose. With the spread of computers, many professionals, educators, and students have turned to computer algebra systems that are specifically designed to perform difficult or tedious tasks, including integration. Symbolic integration has been one of the motivations for the development of the first such systems, like Macsyma and Maple. |
Homogeneous model Summary Homogeneous_model Since the 1970s, the subject has been shaped decisively by Saharon Shelah's stability theory. Compared to other areas of mathematical logic such as proof theory, model theory is often less concerned with formal rigour and closer in spirit to classical mathematics. This has prompted the comment that "if proof theory is about the sacred, then model theory is about the profane". |
Network model Overview Network_model > Overview While the hierarchical database model structures data as a tree of records, with each record having one parent record and many children, the network model allows each record to have multiple parent and child records, forming a generalized graph structure. This property applies at two levels: the schema is a generalized graph of record types connected by relationship types (called "set types" in CODASYL), and the database itself is a generalized graph of record occurrences connected by relationships (CODASYL "sets"). Cycles are permitted at both levels. |
Lyapunov's central limit theorem Common misconceptions Central_Limit_Theorem > Remarks > Common misconceptions Studies have shown that the central limit theorem is subject to several common but serious misconceptions, some of which appear in widely-used textbooks. These include the beliefs that: The theorem applies to random sampling of any variable, rather than to the mean values (or sums) of iid random variables extracted from a population by repeated sampling. That is, the theorem assumes the random sampling produces a sampling distribution formed from different values of means (or sums) of such random variables. The theorem ensures that random sampling leads to the emergence of a normal distribution for sufficiently large samples of any random variable, regardless of the population distribution. |
Dorsolateral prefrontal cortex Schizophrenia Dorsolateral_prefrontal_cortex > Clinical significance > Schizophrenia Schizophrenia may be partially attributed to a lack in activity in the frontal lobe. The dorsolateral prefrontal cortex is especially underactive when a person has chronic schizophrenia. Schizophrenia is also related to lack of dopamine neurotransmitter in the frontal lobe. The DLPFC dysfunctions are unique among the schizophrenia patients as those that are diagnosed with depression do not tend to have the same abnormal activation in the DLPFC during working memory-related tasks. |
Line marker Use Line_marker > Use Line markers are generally used on permanent guidelines to provide critical information to divers following the line. The slots and notches provided are used to wrap the line to secure the marker in place. A simple passage of the line through the enlarged area at the base of the two slots will allow the marker to slide along the line, or even fall off if brushed by a diver. To more securely fasten the marker, an extra wrap may be added at each slot. |
Physical organic Kinetic isotope effect Physical_organic > Kinetics > Kinetic isotope effect Although a rate law provides the stoichiometry of the transition state structure, it does not provide any information about breaking or forming bonds. The substitution of an isotope near a reactive position often leads to a change in the rate of a reaction. Isotopic substitution changes the potential energy of reaction intermediates and transition states because heavier isotopes form stronger bonds with other atoms. Atomic mass affects the zero-point vibrational state of the associated molecules, shorter and stronger bonds in molecules with heavier isotopes and longer, weaker bonds in molecules with light isotopes. Because vibrational motions will often change during a course of a reaction, due to the making and breaking of bonds, the frequencies will be affected, and the substitution of an isotope can provide insight into the reaction mechanism and rate law. |
Drug resistant tuberculosis History Antitubercular_agents > History Streptomycin and para-aminosalicylic acid were developed by the mid-1940s. In 1960, Edinburgh City Hospital physician Sir John Crofton, addressed the Royal College of Physicians in London with a lecture titled "Tuberculosis Undefeated", and proposed that "the disease could be conquered, once and for all". With his colleagues at Edinburgh, he recognised that germs that developed only a mild resistance to one drug was significant. His team showed that when treating new cases of TB, strict compliance to a combination of three therapies, or the triple therapy, (streptomycin, para-aminosalicylic acid and isoniazid) could provide a complete cure. It became known as the 'Edinburgh method' and became standard treatment for at least 15 years. In the 1970s it was recognised that combining isoniazid and rifampin could reduce the duration of treatment from 18 to nine months, and in the 1980s the duration of treatment was further shortened by adding pyrazinamide. |
Socket wrench History Ratchet_wrench > History The hex form allows easier wrenching in confined surroundings (where nearby obstacles obstruct the swing of the wrench), because fewer degrees of arc are needed on each swing before it is possible to reposition the wrench onto the next set of flats. Ratchet wrenches further reduce this problem, as the wrench need only swing as many degrees as it takes for the ratchet pawl to catch the next tooth. The quick release feature common to ratchets was invented and patented (U.S. Patent 3,208,318) by Peter M. Roberts |
Continuity at a point Defining topologies via continuous functions Continuous_mapping > Continuous functions between topological spaces > Defining topologies via continuous functions Given a function where X is a topological space and S is a set (without a specified topology), the final topology on S is defined by letting the open sets of S be those subsets A of S for which f − 1 ( A ) {\displaystyle f^{-1}(A)} is open in X. If S has an existing topology, f is continuous with respect to this topology if and only if the existing topology is coarser than the final topology on S. Thus the final topology can be characterized as the finest topology on S that makes f continuous. If f is surjective, this topology is canonically identified with the quotient topology under the equivalence relation defined by f. Dually, for a function f from a set S to a topological space X, the initial topology on S is defined by designating as an open set every subset A of S such that A = f − 1 ( U ) {\displaystyle A=f^{-1}(U)} for some open subset U of X. If S has an existing topology, f is continuous with respect to this topology if and only if the existing topology is finer than the initial topology on S. Thus the initial topology can be characterized as the coarsest topology on S that makes f continuous. If f is injective, this topology is canonically identified with the subspace topology of S, viewed as a subset of X. A topology on a set S is uniquely determined by the class of all continuous functions S → X {\displaystyle S\to X} into all topological spaces X. Dually, a similar idea can be applied to maps X → S . {\displaystyle X\to S.} |
Unsaturated polyester Synthetic Unsaturated_polyester > Types > Synthetic Increasing the aromatic parts of polyesters increases their glass transition temperature, melting temperature, thermostability, chemical stability, and solvent resistance. Polyesters can also be telechelic oligomers like the polycaprolactone diol (PCL) and the polyethylene adipate diol (PEA). They are then used as prepolymers. |
Vital Product Data Summary Vital_Product_Data Parallel ATA and USB devices also provide similar data, but do not refer to it as VPD. VPD data is typically burned onto EEPROMs associated with various hardware components, or can be queried through attached I2C buses. It is used by firmware (for example, OpenFirmware) to determine the nature of the system hardware, and to shield the operation of the firmware from minor changes and variations of hardware implementations within a given machine model number. |
Measurement and Signature Intelligence Terminology Measurement_and_Signature_Intelligence > Terminology In the context of MASINT, measurement relates to the finite metric parameters of targets and signature covers the distinctive features of phenomena, equipment, or objects as they are sensed by the collection instrument(s). The signature is used to recognize the phenomenon (the equipment or object) once its distinctive features are detected.MASINT measurement searches for differences from known norms, and characterizes the signatures of new phenomena. For example, the first time a new rocket fuel exhaust is measured, it would be a deviation from a norm. When the properties of that exhaust are measured, such as its thermal energy, spectral analysis of its light (i.e., spectrometry), etc., those properties become a new signature in the MASINT database. |
Antibiotic prophylaxis Antibiotic selection Prophylactic_antibiotics > For humans > Antibiotic selection Cephalosporins remain the preferred drugs for perioperative prophylaxis due to their low toxicity. Parenteral systemic antibiotics seem to be more appropriate than oral or topical antibiotics because the chosen antibiotics must reach high concentrations at all sites of danger. |
Blood sugar regulation Glucagon Blood_glucose_regulation > Mechanisms > Glucagon If the blood glucose level falls to dangerously low levels (as during very heavy exercise or lack of food for extended periods), the alpha cells of the pancreas release glucagon, a peptide hormone which travels through the blood to the liver, where it binds to glucagon receptors on the surface of liver cells and stimulates them to break down glycogen stored inside the cells into glucose (this process is called glycogenolysis). The cells release the glucose into the bloodstream, increasing blood sugar levels. Hypoglycemia, the state of having low blood sugar, is treated by restoring the blood glucose level to normal by the ingestion or administration of dextrose or carbohydrate foods. It is often self-diagnosed and self-medicated orally by the ingestion of balanced meals. In more severe circumstances, it is treated by injection or infusion of glucagon. |
Conformastatic spacetimes Summary Conformastatic_spacetimes Conformastatic spacetimes refer to a special class of static solutions to Einstein's equation in general relativity. |
Pseudoscalar Summary Pseudoscalar_(physics) In linear algebra, a pseudoscalar is a quantity that behaves like a scalar, except that it changes sign under a parity inversion while a true scalar does not. A pseudoscalar, when multiplied by an ordinary vector, becomes a pseudovector (or axial vector); a similar construction creates the pseudotensor. A pseudoscalar also results from any scalar product between a pseudovector and an ordinary vector. The prototypical example of a pseudoscalar is the scalar triple product, which can be written as the scalar product between one of the vectors in the triple product and the cross product between the two other vectors, where the latter is a pseudovector. |
Epidemics (journal) Summary Epidemics_(journal) Epidemics is a peer-reviewed academic journal of epidemics. It is published by Elsevier. Its founding editors include Neil Ferguson. == References == |
State machine replication State machine State_machine_replication > Problem definition > State machine For the subsequent discussion a State Machine will be defined as the following tuple of values (See also Mealy machine and Moore Machine): A set of States A set of Inputs A set of Outputs A transition function (Input × State → State) An output function (Input × State → Output) A distinguished State called Start.A State Machine begins at the State labeled Start. Each Input received is passed through the transition and output function to produce a new State and an Output. The State is held stable until a new Input is received, while the Output is communicated to the appropriate receiver. This discussion requires a State Machine to be deterministic: multiple copies of the same State Machine begin in the Start state, and receiving the same Inputs in the same order will arrive at the same State having generated the same Outputs. Typically, systems based on State Machine Replication voluntarily restrict their implementations to use finite-state machines to simplify error recovery. |
Capecitabine Adverse effects Capecitabine > Adverse effects Adverse effects by frequency: Very common (>10% frequency) Notes on adverse effects: |
Cognitive vulnerability Feedback loop Cognitive_vulnerability > Psychological problems > Depression > Dual process model > Feedback loop The feedback loop in the dual process model is between self referent cognition and dysphoria. The feedback loop establishes an inability to apply reflective processing to correct negative biases. |
Signal velocity Summary Signal_velocity However, in a few special cases (e.g., media designed to amplify the front-most parts of a pulse and then attenuate the back section of the pulse), group velocity can exceed the speed of light in vacuum, while the signal velocity will still be less than or equal to the speed of light in vacuum. In electronic circuits, signal velocity is one member of a group of five closely related parameters. In these circuits, signals are usually treated as operating in TEM (Transverse ElectroMagnetic) mode. |
Lipid emulsion Cardioprotective agent Lipid_emulsion > Research > Cardioprotective agent The hydrogen flux disrupts the mitochondrial membrane potential and results in mitochondrial swelling, outer membrane rupture, and the release of pro-apoptotic factors. These changes impair mitochondrial energy production and drive cardiac myocyte apoptosis. |
Micropower Summary Micropower Micropower describes the use of very small electric generators and prime movers or devices to convert heat or motion to electricity, for use close to the generator. The generator is typically integrated with microelectronic devices and produces "several watts of power or less." These devices offer the promise of a power source for portable electronic devices which is lighter weight and has a longer operating time than batteries. |
Queue number Related invariants Queue_number > Related invariants The book thickness may be much larger than the queue number: ternary Hamming graphs have logarithmic queue number but polynomially-large book thickness and there are graphs with queue number 4 that have arbitrarily large book thickness. Heath, Leighton & Rosenberg (1992) conjectured that the queue number is at most a linear function of the book thickness, but no functional bound in this direction is known. It is known that, if all bipartite graphs with 3-page book embeddings have bounded queue number, then all graphs with bounded book thickness have bounded queue number.Ganley & Heath (2001) asked whether the queue number of a graph could be bounded as a function of its treewidth, and cited an unpublished Ph.D. dissertation of S. V. Pemmaraju as providing evidence that the answer was no: planar 3-trees appeared from this evidence to have unbounded queue number. However, the queue number was subsequently shown to be bounded by a (doubly exponential) function of the treewidth. |
Recursive Bayesian estimation Model Recursive_Bayesian_estimation > Model (This is achieved by marginalising out the previous states and dividing by the probability of the measurement set.) This leads to the predict and update steps of the Kalman filter written probabilistically. The probability distribution associated with the predicted state is the sum (integral) of the products of the probability distribution associated with the transition from the (k - 1)-th timestep to the k-th and the probability distribution associated with the previous state, over all possible x k − 1 {\displaystyle x_{k-1}} . |
IPO Model System characteristics IPO_Model > System characteristics The more open the system is, the more complex it normally would be, due to lower predictability of its components. Those that have no interactions with the environment at all are closed. In practice, however, a completely closed system is merely liveable, due to loss of practical usage of the output. |
Nowhere dense set Examples Nowhere-dense_set > Examples R {\displaystyle \mathbb {R} } viewed as the horizontal axis in the Euclidean plane is nowhere dense in R 2 . {\displaystyle \mathbb {R} ^{2}.} Z {\displaystyle \mathbb {Z} } is nowhere dense in R {\displaystyle \mathbb {R} } but the rationals Q {\displaystyle \mathbb {Q} } are not (they are dense everywhere). |
Currying Category theory Currying > Definition > Category theory The setting of cartesian closed categories is sufficient for the discussion of classical logic; the more general setting of closed monoidal categories is suitable for quantum computation.The difference between these two is that the product for cartesian categories (such as the category of sets, complete partial orders or Heyting algebras) is just the Cartesian product; it is interpreted as an ordered pair of items (or a list). Simply typed lambda calculus is the internal language of cartesian closed categories; and it is for this reason that pairs and lists are the primary types in the type theory of LISP, Scheme and many functional programming languages. By contrast, the product for monoidal categories (such as Hilbert space and the vector spaces of functional analysis) is the tensor product. |
Hub gear Advantages Hub_gear > Advantages This can be useful for commuter cycling with frequent stops and for mountain biking in rough terrain. Hub gears can be simpler to use for inexperienced riders, because there is generally only a single shifter to operate and there are no overlapping gear ratios. By contrast, modern derailleur systems often have two shifters, and require some forethought to avoid problematic gear combinations. |
Shmoo plot Description Shmoo_plot > Description Shmoo plots are often used to represent the results of the testing of complex electronic systems such as computers or integrated circuits such as DRAMs, ASICs or microprocessors. The plot usually shows the range of conditions in which the device under test operates (in adherence with some remaining set of specifications). For example, when testing semiconductor memory: voltages, temperature, and refresh rates can be varied over specified ranges and only certain combinations of these factors will allow the device to operate. Plotted on independent axes (voltage, temperature, refresh rates), the range of working values will enclose a three-dimensional, usually oddly-shaped volume. |
Imperative programming C Imperative_paradigm > Examples > C An example usage would be the function int increment_counter(){ static int counter = 0; counter++; return counter;}The stack region is a contiguous block of memory located near the top memory address. Variables placed in the stack are populated from top to bottom. A stack pointer is a special-purpose register that keeps track of the last memory address populated. |
Strong acid Summary Strong_acid HA ↽ − − ⇀ H + + A − {\displaystyle {\ce {HA <=> H+ + A-}}} Acetic acid ( CH 3 COOH {\displaystyle {\ce {CH3COOH}}} ) is an example of a weak acid. The strength of a weak acid is quantified by its acid dissociation constant, K a {\displaystyle K_{{\ce {a}}}} value. The strength of a weak organic acid may depend on substituent effects. |
Traditional Balsamic Vinegar Physical properties Traditional_Balsamic_Vinegar > Physical properties The most relevant physical properties of the TBV are: pH is usually lower than 3; it is a measure of the extent of carboxylic acids dissociation. Density is usually intended as mass density at 20 °C, it cannot be lower than 1.24 g/ml (TBVM) and 1.20 g/ml (TBVRE); it is a measure of the extent of the solute concentration, as well as of water evaporation. Refractive index is usually expressed with Brix scale and reaches on average 73°Bx. |
Augustin-Jean Fresnel Historical context: From Newton to Biot Conical_refraction > Contributions to physical optics > Historical context: From Newton to Biot The appreciation of Fresnel's reconstruction of physical optics might be assisted by an overview of the fragmented state in which he found the subject. In this subsection, optical phenomena that were unexplained or whose explanations were disputed are named in bold type. The corpuscular theory of light, favored by Isaac Newton and accepted by nearly all of Fresnel's seniors, easily explained rectilinear propagation: the corpuscles obviously moved very fast, so that their paths were very nearly straight. The wave theory, as developed by Christiaan Huygens in his Treatise on Light (1690), explained rectilinear propagation on the assumption that each point crossed by a traveling wavefront becomes the source of a secondary wavefront. |
Thoracic skeleton Atelectasis Human_thorax > Human thorax > Clinical significance > Atelectasis Another non-cardiac cause of chest pain is atelectasis. It is a condition that occurs when a portion of the lung collapses from being airless. When bronchial tubes are blocked, this condition develops and causes patients to feel shortness of breath. The most common cause of atelectasis is when a bronchi that extends from the windpipe is blocked and traps air. The blockage may be caused by something inside the bronchus, such as a plug of mucus, a tumour, or an inhaled foreign object such as a coin, piece of food, or a toy. It is possible for something outside of the bronchus to cause the blockage. |
Abstract concept Theory-theory Abstract_concept > Notable theories on the structure of concepts > Theory-theory Theory-theory is a reaction to the previous two theories and develops them further. This theory postulates that categorization by concepts is something like scientific theorizing. Concepts are not learned in isolation, but rather are learned as a part of our experiences with the world around us. In this sense, concepts' structure relies on their relationships to other concepts as mandated by a particular mental theory about the state of the world. |
K-d tree Summary K-d_tree In computer science, a k-d tree (short for k-dimensional tree) is a space-partitioning data structure for organizing points in a k-dimensional space. k-d trees are a useful data structure for several applications, such as searches involving a multidimensional search key (e.g. range searches and nearest neighbor searches) and creating point clouds. k-d trees are a special case of binary space partitioning trees. |
Iodoacetic acid Possible cancer therapy Iodoacetic_acid > Possible cancer therapy Several studies have shown iodoacetate has anti-tumor effects. In 2002 Dr. Fawzia Fahim showed that "a single IAA treatment of tumor-bearing mice significantly increased the levels of plasma lactate dehydrogenase (LDH) activity, while it also significantly decreased the levels of plasma glucose and liver total protein, RNA and DNA, compared to normal controls." In 1975 Melvin S. Rhein, Joyce A. Filppi and Victor S. Moore showed that iodoacetate improved the immune response of bone marrow. In 1966 Charles A. Apffel, Barry G. Arnason & John H. Peters showed anti-tumor activity for iodoacetate. |
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