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7738
https://en.wikipedia.org/wiki/Chiropractic
Chiropractic
Chiropractic () is a form of alternative medicine concerned with the diagnosis, treatment and prevention of mechanical disorders of the musculoskeletal system, especially of the spine. It is based on several pseudoscientific ideas. Many chiropractors (often known informally as chiros), especially those in the field's ...
Biology and health sciences
Alternative and traditional medicine
Health
7739
https://en.wikipedia.org/wiki/Carbide
Carbide
In chemistry, a carbide usually describes a compound composed of carbon and a metal. In metallurgy, carbiding or carburizing is the process for producing carbide coatings on a metal piece. Interstitial / Metallic carbides The carbides of the group 4, 5 and 6 transition metals (with the exception of chromium) are oft...
Physical sciences
Ceramic compounds
Chemistry
7783
https://en.wikipedia.org/wiki/Coriolis%20force
Coriolis force
In physics, the Coriolis force is an inertial (or fictitious) force that acts on objects in motion within a frame of reference that rotates with respect to an inertial frame. In a reference frame with clockwise rotation, the force acts to the left of the motion of the object. In one with anticlockwise (or counterclockw...
Physical sciences
Classical mechanics
null
7794
https://en.wikipedia.org/wiki/Crystallography
Crystallography
Crystallography is the branch of science devoted to the study of molecular and crystalline structure and properties. The word crystallography is derived from the Ancient Greek word (; "clear ice, rock-crystal"), and (; "to write"). In July 2012, the United Nations recognised the importance of the science of crystallo...
Physical sciences
Crystallography
null
7808
https://en.wikipedia.org/wiki/Cyprinodontiformes
Cyprinodontiformes
Cyprinodontiformes is an order of ray-finned fish, comprising mostly small, freshwater fish. Many popular aquarium fish, such as killifish and live-bearers, are included. They are closely related to the Atheriniformes and are occasionally included with them. A colloquial term for the order as a whole is toothcarps,...
Biology and health sciences
Acanthomorpha
null
7819
https://en.wikipedia.org/wiki/Cactus
Cactus
A cactus (: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (), a family of the order Caryophyllales comprising about 127 genera with some 1,750 known species. The word cactus derives, through Latin, from the Ancient Greek word (káktos), a name originally used by Theophrastus for a...
Biology and health sciences
Caryophyllales
null
7834
https://en.wikipedia.org/wiki/Chain%20reaction
Chain reaction
A chain reaction is a sequence of reactions where a reactive product or by-product causes additional reactions to take place. In a chain reaction, positive feedback leads to a self-amplifying chain of events. Chain reactions are one way that systems which are not in thermodynamic equilibrium can release energy or incr...
Physical sciences
Basics_3
Chemistry
7839
https://en.wikipedia.org/wiki/Stellar%20corona
Stellar corona
A corona (: coronas or coronae) is the outermost layer of a star's atmosphere. It is a hot but relatively dim region of plasma populated by intermittent coronal structures known as solar prominences or filaments. The Sun's corona lies above the chromosphere and extends millions of kilometres into outer space. Coronal ...
Physical sciences
Solar System
Astronomy
7844
https://en.wikipedia.org/wiki/Chimpanzee
Chimpanzee
The chimpanzee (; Pan troglodytes), also simply known as the chimp, is a species of great ape native to the forests and savannahs of tropical Africa. It has four confirmed subspecies and a fifth proposed one. When its close relative the bonobo was more commonly known as the pygmy chimpanzee, this species was often call...
Biology and health sciences
Primates
null
7849
https://en.wikipedia.org/wiki/Crystallographic%20defect
Crystallographic defect
A crystallographic defect is an interruption of the regular patterns of arrangement of atoms or molecules in crystalline solids. The positions and orientations of particles, which are repeating at fixed distances determined by the unit cell parameters in crystals, exhibit a periodic crystal structure, but this is usual...
Physical sciences
Crystallography
Physics
7890
https://en.wikipedia.org/wiki/Dune
Dune
A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat regions covered with wind-swept sand or dunes, with little or no vegetation, ...
Physical sciences
Aeolian landforms
null
7903
https://en.wikipedia.org/wiki/Diffie%E2%80%93Hellman%20key%20exchange
Diffie–Hellman key exchange
Diffie–Hellman (DH) key exchange is a mathematical method of securely generating a symmetric cryptographic key over a public channel and was one of the first public-key protocols as conceived by Ralph Merkle and named after Whitfield Diffie and Martin Hellman. DH is one of the earliest practical examples of public key ...
Technology
Computer security
null
7921
https://en.wikipedia.org/wiki/Derivative
Derivative
In mathematics, the derivative is a fundamental tool that quantifies the sensitivity to change of a function's output with respect to its input. The derivative of a function of a single variable at a chosen input value, when it exists, is the slope of the tangent line to the graph of the function at that point. The tan...
Mathematics
Calculus and analysis
null
7938
https://en.wikipedia.org/wiki/Diatomic%20molecule
Diatomic molecule
Diatomic molecules () are molecules composed of only two atoms, of the same or different chemical elements. If a diatomic molecule consists of two atoms of the same element, such as hydrogen () or oxygen (), then it is said to be homonuclear. Otherwise, if a diatomic molecule consists of two different atoms, such as ca...
Physical sciences
Substance
Chemistry
7955
https://en.wikipedia.org/wiki/DNA
DNA
Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of all known organisms and many viruses. DNA and ribonucleic acid (RNA) are nucleic acid...
Biology and health sciences
Chemistry
null
7985
https://en.wikipedia.org/wiki/Dill
Dill
Dill (Anethum graveolens) is an annual herb in the celery family Apiaceae. It is native to North Africa, Iran, and the Arabian Peninsula; it is grown widely in Eurasia, where its leaves and seeds are used as a herb or spice for flavouring food. Etymology The word dill and its close relatives are found in most of the ...
Biology and health sciences
Herbs and spices
Plants
7992
https://en.wikipedia.org/wiki/Devonian
Devonian
The Devonian ( ) is a geologic period and system of the Paleozoic era during the Phanerozoic eon, spanning 60.3 million years from the end of the preceding Silurian period at million years ago (Ma), to the beginning of the succeeding Carboniferous period at Ma. It is the fourth period of both the Paleozoic and the Ph...
Physical sciences
Geological timescale
Earth science
8005
https://en.wikipedia.org/wiki/Dentistry
Dentistry
Dentistry, also known as dental medicine and oral medicine, is the branch of medicine focused on the teeth, gums, and mouth. It consists of the study, diagnosis, prevention, management, and treatment of diseases, disorders, and conditions of the mouth, most commonly focused on dentition (the development and arrangement...
Biology and health sciences
Health, fitness, and medicine
null
8011
https://en.wikipedia.org/wiki/Alcohol%20intoxication
Alcohol intoxication
Alcohol intoxication, commonly described in higher doses as drunkenness or inebriation, and known in overdose as alcohol poisoning, is the behavior and physical effects caused by recent consumption of alcohol. The technical term intoxication in common speech may suggest that a large amount of alcohol has been consumed,...
Biology and health sciences
Drugs and pharmacology
null
8013
https://en.wikipedia.org/wiki/Data%20compression
Data compression
In information theory, data compression, source coding, or bit-rate reduction is the process of encoding information using fewer bits than the original representation. Any particular compression is either lossy or lossless. Lossless compression reduces bits by identifying and eliminating statistical redundancy. No info...
Mathematics
Discrete mathematics
null
8072
https://en.wikipedia.org/wiki/Disease
Disease
A disease is a particular abnormal condition that adversely affects the structure or function of all or part of an organism and is not immediately due to any external injury. Diseases are often known to be medical conditions that are associated with specific signs and symptoms. A disease may be caused by external facto...
Biology and health sciences
Science and medicine
null
8078
https://en.wikipedia.org/wiki/Dynamite
Dynamite
Dynamite is an explosive made of nitroglycerin, sorbents (such as powdered shells or clay), and stabilizers. It was invented by the Swedish chemist and engineer Alfred Nobel in Geesthacht, Northern Germany, and was patented in 1867. It rapidly gained wide-scale use as a more robust alternative to the traditional black ...
Technology
Material and chemical
null
8082
https://en.wikipedia.org/wiki/Diamond
Diamond
Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond as a form of carbon is tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of electricity, and insoluble in water. Another solid form of carbon known as graphite ...
Physical sciences
Chemical elements_2
null
8102
https://en.wikipedia.org/wiki/Dysprosium
Dysprosium
Dysprosium is a chemical element; it has symbol Dy and atomic number 66. It is a rare-earth element in the lanthanide series with a metallic silver luster. Dysprosium is never found in nature as a free element, though, like other lanthanides, it is found in various minerals, such as xenotime. Naturally occurring dyspro...
Physical sciences
Chemical elements_2
null
8104
https://en.wikipedia.org/wiki/Desertification
Desertification
Desertification is a type of gradual land degradation of fertile land into arid desert due to a combination of natural processes and human activities. The immediate cause of desertification is the loss of most vegetation. This is driven by a number of factors, alone or in combination, such as drought, climatic shifts,...
Physical sciences
Biomes: General
Earth science
8131
https://en.wikipedia.org/wiki/Dendrite
Dendrite
A dendrite (from Greek δένδρον déndron, "tree") or dendron is a branched cytoplasmic process that extends from a nerve cell that propagates the electrochemical stimulation received from other neural cells to the cell body, or soma, of the neuron from which the dendrites project. Electrical stimulation is transmitted on...
Biology and health sciences
Nervous system
Biology
8143
https://en.wikipedia.org/wiki/December
December
December is the twelfth and final month of the year in the Julian and Gregorian calendars. Its length is 31 days. December's name derives from the Latin word decem (meaning ten) because it was originally the tenth month of the year in the calendar of Romulus , which began in March. The winter days following December ...
Technology
Months
null
8179
https://en.wikipedia.org/wiki/Dye
Dye
A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution and may require a mordant to improve the fastness of the dye on the fiber. The...
Technology
Techniques_2
null
8187
https://en.wikipedia.org/wiki/Descriptive%20statistics
Descriptive statistics
A descriptive statistic (in the count noun sense) is a summary statistic that quantitatively describes or summarizes features from a collection of information, while descriptive statistics (in the mass noun sense) is the process of using and analysing those statistics. Descriptive statistics is distinguished from infer...
Mathematics
Statistics
null
8214
https://en.wikipedia.org/wiki/Decimal
Decimal
The decimal numeral system (also called the base-ten positional numeral system and denary or decanary) is the standard system for denoting integer and non-integer numbers. It is the extension to non-integer numbers (decimal fractions) of the Hindu–Arabic numeral system. The way of denoting numbers in the decimal syste...
Mathematics
Basics
null
8221
https://en.wikipedia.org/wiki/Death
Death
Death is the end of life; the irreversible cessation of all biological functions that sustain a living organism. The remains of a former organism normally begin to decompose shortly after death. Death eventually and inevitably occurs in all organisms. Some organisms, such as Turritopsis dohrnii, are biologically immor...
Biology and health sciences
Science and medicine
null
8242
https://en.wikipedia.org/wiki/Debian
Debian
Debian (), also known as Debian GNU/Linux, is a free and open source Linux distribution, developed by the Debian Project, which was established by Ian Murdock in August 1993. Debian is one of the oldest operating systems based on the Linux kernel, and is the basis for many other Linux distributions. As of September 20...
Technology
Operating Systems
null
8254
https://en.wikipedia.org/wiki/Diode
Diode
A diode is a two-terminal electronic component that conducts current primarily in one direction (asymmetric conductance). It has low (ideally zero) resistance in one direction and high (ideally infinite) resistance in the other. A semiconductor diode, the most commonly used type today, is a crystalline piece of semico...
Technology
Components
null
8263
https://en.wikipedia.org/wiki/Dissociation%20constant
Dissociation constant
In chemistry, biochemistry, and pharmacology, a dissociation constant (KD) is a specific type of equilibrium constant that measures the propensity of a larger object to separate (dissociate) reversibly into smaller components, as when a complex falls apart into its component molecules, or when a salt splits up into its...
Physical sciences
Thermodynamics
Chemistry
8267
https://en.wikipedia.org/wiki/Dimensional%20analysis
Dimensional analysis
In engineering and science, dimensional analysis is the analysis of the relationships between different physical quantities by identifying their base quantities (such as length, mass, time, and electric current) and units of measurement (such as metres and grams) and tracking these dimensions as calculations or compari...
Physical sciences
Basics
Basics and measurement
8271
https://en.wikipedia.org/wiki/Digital%20television
Digital television
Digital television (DTV) is the transmission of television signals using digital encoding, in contrast to the earlier analog television technology which used analog signals. At the time of its development it was considered an innovative advancement and represented the first significant evolution in television technolog...
Technology
Broadcasting
null
8301
https://en.wikipedia.org/wiki/Distillation
Distillation
Distillation, also classical distillation, is the process of separating the component substances of a liquid mixture of two or more chemically discrete substances; the separation process is realized by way of the selective boiling of the mixture and the condensation of the vapors in a still. Distillation can operate o...
Physical sciences
Separation processes
null
8303
https://en.wikipedia.org/wiki/Down%20syndrome
Down syndrome
Down syndrome or Down's syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. It is usually associated with developmental delays, mild to moderate intellectual disability, and characteristic physical features. The parents of the affected indi...
Biology and health sciences
Disability
null
8305
https://en.wikipedia.org/wiki/Dyslexia
Dyslexia
Dyslexia, previously known as word blindness, is a learning disability that affects either reading or writing. Different people are affected to different degrees. Problems may include difficulties in spelling words, reading quickly, writing words, "sounding out" words in the head, pronouncing words when reading aloud a...
Biology and health sciences
Disability
null
8311
https://en.wikipedia.org/wiki/Dinosaur
Dinosaur
Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is a subject of active research. They became the dominant terrestrial vertebrates after th...
Biology and health sciences
Biology
null
8315
https://en.wikipedia.org/wiki/Diamagnetism
Diamagnetism
Diamagnetism is the property of materials that are repelled by a magnetic field; an applied magnetic field creates an induced magnetic field in them in the opposite direction, causing a repulsive force. In contrast, paramagnetic and ferromagnetic materials are attracted by a magnetic field. Diamagnetism is a quantum me...
Physical sciences
Magnetostatics
Physics
8324
https://en.wikipedia.org/wiki/Difference%20engine
Difference engine
A difference engine is an automatic mechanical calculator designed to tabulate polynomial functions. It was designed in the 1820s, and was first created by Charles Babbage. The name difference engine is derived from the method of finite differences, a way to interpolate or tabulate functions by using a small set of pol...
Technology
Early computers
null
8328
https://en.wikipedia.org/wiki/Divergence
Divergence
In vector calculus, divergence is a vector operator that operates on a vector field, producing a scalar field giving the quantity of the vector field's source at each point. More technically, the divergence represents the volume density of the outward flux of a vector field from an infinitesimal volume around a given p...
Mathematics
Multivariable and vector calculus
null
8336
https://en.wikipedia.org/wiki/Decision%20problem
Decision problem
In computability theory and computational complexity theory, a decision problem is a computational problem that can be posed as a yes–no question based on the given input values. An example of a decision problem is deciding with the help of an algorithm whether a given natural number is prime. Another example is the pr...
Mathematics
Computability theory
null
8376
https://en.wikipedia.org/wiki/Day
Day
A day is the time period of a full rotation of the Earth with respect to the Sun. On average, this is 24 hours (86,400 seconds). As a day passes at a given location it experiences morning, noon, afternoon, evening, and night. This daily cycle drives circadian rhythms in many organisms, which are vital to many life pro...
Physical sciences
Physics
null
8377
https://en.wikipedia.org/wiki/Database
Database
In computing, a database is an organized collection of data or a type of data store based on the use of a database management system (DBMS), the software that interacts with end users, applications, and the database itself to capture and analyze the data. The DBMS additionally encompasses the core facilities provided t...
Technology
Computer software
null
8378
https://en.wikipedia.org/wiki/Dipole
Dipole
In physics, a dipole () is an electromagnetic phenomenon which occurs in two ways: An electric dipole deals with the separation of the positive and negative electric charges found in any electromagnetic system. A simple example of this system is a pair of charges of equal magnitude but opposite sign separated by some ...
Physical sciences
Basics_9
null
8389
https://en.wikipedia.org/wiki/Major%20depressive%20disorder
Major depressive disorder
Major depressive disorder (MDD), also known as clinical depression, is a mental disorder characterized by at least two weeks of pervasive low mood, low self-esteem, and loss of interest or pleasure in normally enjoyable activities. Introduced by a group of US clinicians in the mid-1970s, the term was adopted by the Ame...
Biology and health sciences
Mental disorder
null
8398
https://en.wikipedia.org/wiki/Dimension
Dimension
In physics and mathematics, the dimension of a mathematical space (or object) is informally defined as the minimum number of coordinates needed to specify any point within it. Thus, a line has a dimension of one (1D) because only one coordinate is needed to specify a point on itfor example, the point at 5 on a number l...
Mathematics
Geometry
null
8407
https://en.wikipedia.org/wiki/Dodecahedron
Dodecahedron
In geometry, a dodecahedron (; ) or duodecahedron is any polyhedron with twelve flat faces. The most familiar dodecahedron is the regular dodecahedron with regular pentagons as faces, which is a Platonic solid. There are also three regular star dodecahedra, which are constructed as stellations of the convex form. All ...
Mathematics
Three-dimensional space
null
8410
https://en.wikipedia.org/wiki/Decibel
Decibel
The decibel (symbol: dB) is a relative unit of measurement equal to one tenth of a bel (B). It expresses the ratio of two values of a power or root-power quantity on a logarithmic scale. Two signals whose levels differ by one decibel have a power ratio of 101/10 (approximately ) or root-power ratio of 101/20 (approxima...
Physical sciences
Other
null
8420
https://en.wikipedia.org/wiki/Dodo
Dodo
The dodo (Raphus cucullatus) is an extinct flightless bird that was endemic to the island of Mauritius, which is east of Madagascar in the Indian Ocean. The dodo's closest relative was the also-extinct and flightless Rodrigues solitaire. The two formed the subtribe Raphina, a clade of extinct flightless birds that were...
Biology and health sciences
Columbiformes
null
8429
https://en.wikipedia.org/wiki/Density
Density
Density (volumetric mass density or specific mass) is a substance's mass per unit of volume. The symbol most often used for density is ρ (the lower case Greek letter rho), although the Latin letter D can also be used. Mathematically, density is defined as mass divided by volume: where ρ is the density, m is the mass,...
Physical sciences
Classical mechanics
null
8449
https://en.wikipedia.org/wiki/Developmental%20biology
Developmental biology
Developmental biology is the study of the process by which animals and plants grow and develop. Developmental biology also encompasses the biology of regeneration, asexual reproduction, metamorphosis, and the growth and differentiation of stem cells in the adult organism. Perspectives The main processes involved in t...
Biology and health sciences
Development
null
8463
https://en.wikipedia.org/wiki/Dubnium
Dubnium
Dubnium is a synthetic chemical element; it has symbol Db and atomic number 105. It is highly radioactive: the most stable known isotope, dubnium-268, has a half-life of about 16 hours. This greatly limits extended research on the element. Dubnium does not occur naturally on Earth and is produced artificially. The Sov...
Physical sciences
Group 5
Chemistry
8464
https://en.wikipedia.org/wiki/Disaccharide
Disaccharide
A disaccharide (also called a double sugar or biose) is the sugar formed when two monosaccharides are joined by glycosidic linkage. Like monosaccharides, disaccharides are simple sugars soluble in water. Three common examples are sucrose, lactose, and maltose. Disaccharides are one of the four chemical groupings of ca...
Biology and health sciences
Carbohydrates
Biology
8466
https://en.wikipedia.org/wiki/Dorado
Dorado
Dorado (, ) is a constellation in the Southern Sky. It was named in the late 16th century and is now one of the 88 modern constellations. Its name refers to the mahi-mahi (Coryphaena hippurus), which is known as dorado ("golden") in Spanish, although it has also been depicted as a swordfish. Dorado contains most of the...
Physical sciences
Other
Astronomy
8468
https://en.wikipedia.org/wiki/Determinant
Determinant
In mathematics, the determinant is a scalar-valued function of the entries of a square matrix. The determinant of a matrix is commonly denoted , , or . Its value characterizes some properties of the matrix and the linear map represented, on a given basis, by the matrix. In particular, the determinant is nonzero if and...
Mathematics
Algebra
null
8471
https://en.wikipedia.org/wiki/Delphinus
Delphinus
Delphinus is a small constellation in the Northern Celestial Hemisphere, close to the celestial equator. Its name is the Latin version for the Greek word for dolphin (). It is one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations recognized by the In...
Physical sciences
Other
Astronomy
8483
https://en.wikipedia.org/wiki/Diesel%20cycle
Diesel cycle
The Diesel cycle is a combustion process of a reciprocating internal combustion engine. In it, fuel is ignited by heat generated during the compression of air in the combustion chamber, into which fuel is then injected. This is in contrast to igniting the fuel-air mixture with a spark plug as in the Otto cycle (four-st...
Physical sciences
Thermodynamics
Physics
8492
https://en.wikipedia.org/wiki/Discrete%20mathematics
Discrete mathematics
Discrete mathematics is the study of mathematical structures that can be considered "discrete" (in a way analogous to discrete variables, having a bijection with the set of natural numbers) rather than "continuous" (analogously to continuous functions). Objects studied in discrete mathematics include integers, graphs, ...
Mathematics
Discrete mathematics
null
8494
https://en.wikipedia.org/wiki/DDT
DDT
Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. DDT was first synthesized in 1874 by the Austrian chemist Othmar Zeidler. DD...
Technology
Pest and disease control
null
8501
https://en.wikipedia.org/wiki/Distributed%20computing
Distributed computing
Distributed computing is a field of computer science that studies distributed systems, defined as computer systems whose inter-communicating components are located on different networked computers. The components of a distributed system communicate and coordinate their actions by passing messages to one another in or...
Technology
Computer architecture concepts
null
8506
https://en.wikipedia.org/wiki/DirectX
DirectX
Microsoft DirectX is a collection of application programming interfaces (APIs) for handling tasks related to multimedia, especially game programming and video, on Microsoft platforms. Originally, the names of these APIs all began with "Direct", such as Direct3D, DirectDraw, DirectMusic, DirectPlay, DirectSound, and so ...
Technology
Software development: General
null
8519
https://en.wikipedia.org/wiki/Data%20structure
Data structure
In computer science, a data structure is a data organization and storage format that is usually chosen for efficient access to data. More precisely, a data structure is a collection of data values, the relationships among them, and the functions or operations that can be applied to the data, i.e., it is an algebraic st...
Mathematics
Discrete mathematics
null
8524
https://en.wikipedia.org/wiki/Deuterium
Deuterium
Deuterium (hydrogen-2, symbol H or D, also known as heavy hydrogen) is one of two stable isotopes of hydrogen; the other is protium, or hydrogen-1, H. The deuterium nucleus (deuteron) contains one proton and one neutron, whereas the far more common H has no neutrons. Deuterium has a natural abundance in Earth's oceans ...
Physical sciences
s-Block
Chemistry
8540
https://en.wikipedia.org/wiki/Diesel%20engine
Diesel engine
The diesel engine, named after the German engineer Rudolf Diesel, is an internal combustion engine in which ignition of diesel fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is called a compression-ignition engine (CI engine). This contrasts ...
Technology
Basics_8
null
8578
https://en.wikipedia.org/wiki/Dyne
Dyne
The dyne (symbol: dyn; ) is a derived unit of force specified in the centimetre–gram–second (CGS) system of units, a predecessor of the modern SI. History The name dyne was first proposed as a CGS unit of force in 1873 by a Committee of the British Association for the Advancement of Science. Definition The dyne is d...
Physical sciences
Force
Basics and measurement
8603
https://en.wikipedia.org/wiki/Diffraction
Diffraction
Diffraction is the deviation of waves from straight-line propagation without any change in their energy due to an obstacle or through an aperture. The diffracting object or aperture effectively becomes a secondary source of the propagating wave. Diffraction is the same physical effect as interference, but interference ...
Physical sciences
Waves
null
8612
https://en.wikipedia.org/wiki/Declination
Declination
In astronomy, declination (abbreviated dec; symbol δ) is one of the two angles that locate a point on the celestial sphere in the equatorial coordinate system, the other being hour angle. The declination angle is measured north (positive) or south (negative) of the celestial equator, along the hour circle passing throu...
Physical sciences
Celestial sphere: General
Astronomy
8625
https://en.wikipedia.org/wiki/Differential%20geometry
Differential geometry
Differential geometry is a mathematical discipline that studies the geometry of smooth shapes and smooth spaces, otherwise known as smooth manifolds. It uses the techniques of differential calculus, integral calculus, linear algebra and multilinear algebra. The field has its origins in the study of spherical geometry a...
Mathematics
Geometry
null
8626
https://en.wikipedia.org/wiki/Dhole
Dhole
The dhole ( ; Cuon alpinus) is a canid native to South, East and Southeast Asia. It is anatomically distinguished from members of the genus Canis in several aspects: its skull is convex rather than concave in profile, it lacks a third lower molar and the upper molars possess only a single cusp as opposed to between two...
Biology and health sciences
Canines
Animals
8637
https://en.wikipedia.org/wiki/Door
Door
A door is a hinged or otherwise movable barrier that allows ingress (entry) into and egress (exit) from an enclosure. The created opening in the wall is a doorway or portal. A door's essential and primary purpose is to provide security by controlling access to the doorway (portal). Conventionally, it is a panel that fi...
Technology
Architectural elements
null
8643
https://en.wikipedia.org/wiki/Molecular%20diffusion
Molecular diffusion
Molecular diffusion, often simply called diffusion, is the thermal motion of all (liquid or gas) particles at temperatures above absolute zero. The rate of this movement is a function of temperature, viscosity of the fluid and the size (mass) of the particles. Diffusion explains the net flux of molecules from a region ...
Physical sciences
Statistical mechanics
Physics
8651
https://en.wikipedia.org/wiki/Dark%20matter
Dark matter
In astronomy, dark matter is an invisible and hypothetical form of matter that does not interact with light or other electromagnetic radiation. Dark matter is implied by gravitational effects which cannot be explained by general relativity unless more matter is present than can be observed. Such effects occur in the co...
Physical sciences
Physical cosmology
null
8667
https://en.wikipedia.org/wiki/Double-slit%20experiment
Double-slit experiment
In modern physics, the double-slit experiment demonstrates that light and matter can exhibit behavior of both classical particles and classical waves. This type of experiment was first performed by Thomas Young in 1801, as a demonstration of the wave behavior of visible light. In 1927, Davisson and Germer and, indepen...
Physical sciences
Quantum mechanics
Physics
8688
https://en.wikipedia.org/wiki/Deccan%20Traps
Deccan Traps
The Deccan Traps are a large igneous province of west-central India (17–24°N, 73–74°E). They are one of the largest volcanic features on Earth, taking the form of a large shield volcano. They consist of many layers of solidified flood basalt that together are more than about thick, cover an area of about , and have a ...
Physical sciences
Geologic features
Earth science
8697
https://en.wikipedia.org/wiki/DNA%20ligase
DNA ligase
DNA ligase is a type of enzyme that facilitates the joining of DNA strands together by catalyzing the formation of a phosphodiester bond. It plays a role in repairing single-strand breaks in duplex DNA in living organisms, but some forms (such as DNA ligase IV) may specifically repair double-strand breaks (i.e. a break...
Biology and health sciences
Molecular biology
Biology
8717
https://en.wikipedia.org/wiki/Diprotodon
Diprotodon
Diprotodon (Ancient Greek: "two protruding front teeth") is an extinct genus of marsupial from the Pleistocene of Australia containing one species, D. optatum. The earliest finds date to 1.77 million to 780,000 years ago but most specimens are dated to after 110,000 years ago. Its remains were first unearthed in 1830 i...
Biology and health sciences
Diprotodontia
Animals
8724
https://en.wikipedia.org/wiki/Doppler%20effect
Doppler effect
The Doppler effect (also Doppler shift) is the change in the frequency of a wave in relation to an observer who is moving relative to the source of the wave. The Doppler effect is named after the physicist Christian Doppler, who described the phenomenon in 1842. A common example of Doppler shift is the change of pitch ...
Physical sciences
Waves
null
8733
https://en.wikipedia.org/wiki/Digital%20video
Digital video
Digital video is an electronic representation of moving visual images (video) in the form of encoded digital data. This is in contrast to analog video, which represents moving visual images in the form of analog signals. Digital video comprises a series of digital images displayed in rapid succession, usually at 24, 25...
Technology
Media and communication: Basics
null
8779
https://en.wikipedia.org/wiki/Destroyer
Destroyer
In naval terminology, a destroyer is a fast, maneuverable, long-endurance warship intended to escort larger vessels in a fleet, convoy, or carrier battle group and defend them against a wide range of general threats. They were originally conceived in 1885 by Fernando Villaamil for the Spanish Navy as a defense against ...
Technology
Naval warfare
null
11907381
https://en.wikipedia.org/wiki/Indonesian%20coelacanth
Indonesian coelacanth
The Indonesian coelacanth (Latimeria menadoensis, Indonesian: raja laut), also called Sulawesi coelacanth, is one of two living species of coelacanth, identifiable by its brown color. Latimeria menadoensis is a lobe-finned fish belonging to the class Actinistia and order Coelacanthiformes, classified under the family L...
Biology and health sciences
Fishes: General
Animals
9446968
https://en.wikipedia.org/wiki/Volatile%20%28astrogeology%29
Volatile (astrogeology)
Volatiles are the group of chemical elements and chemical compounds that can be readily vaporized. In contrast with volatiles, elements and compounds that are not readily vaporized are known as refractory substances. On planet Earth, the term 'volatiles' often refers to the volatile components of magma. In astrogeolog...
Physical sciences
Volcanology
Earth science
51852
https://en.wikipedia.org/wiki/Sidewalk
Sidewalk
A sidewalk (North American English) or pavement (British English) is a path along the side of a road. Usually constructed of concrete, pavers, brick, stone, or asphalt, it is designed for pedestrians. A sidewalk is normally higher than the roadway, and separated from it by a curb. There may also be a planted strip betw...
Technology
Road infrastructure
null
51892
https://en.wikipedia.org/wiki/Textile
Textile
Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, different fabric types, etc. At first, the word "textiles" only referred to woven fabrics. However, weaving is not the only manufacturing method, and many other methods were later developed to form text...
Technology
Materials
null
51894
https://en.wikipedia.org/wiki/Putrescine
Putrescine
Putrescine is an organic compound with the formula (CH2)4(NH2)2. It is a colorless solid that melts near room temperature. It is classified as a diamine. Together with cadaverine, it is largely responsible for the foul odor of putrefying flesh, but also contributes to other unpleasant odors. Production Putrescine is p...
Physical sciences
Amides and amines
Chemistry
51896
https://en.wikipedia.org/wiki/Cadaverine
Cadaverine
Cadaverine is an organic compound with the formula (CH2)5(NH2)2. Classified as a diamine, it is a colorless liquid with an unpleasant odor. It is present in small quantities in living organisms but is often associated with the putrefaction of animal tissue. Together with putrescine, it is largely responsible for the fo...
Physical sciences
Amides and amines
Chemistry
51916
https://en.wikipedia.org/wiki/Transcontinental%20railroad
Transcontinental railroad
A transcontinental railroad or transcontinental railway is contiguous railroad trackage that crosses a continental land mass and has terminals at different oceans or continental borders. Such networks may be via the tracks of a single railroad, or via several railroads owned or controlled by multiple railway companies ...
Technology
Ground transportation networks
null
51944
https://en.wikipedia.org/wiki/Dichroism
Dichroism
In optics, a dichroic material is either one which causes visible light to be split up into distinct beams of different wavelengths (colours) (not to be confused with dispersion), or one in which light rays having different polarizations are absorbed by different amounts. In beam splitters The original meaning of dic...
Physical sciences
Optics
Physics
51970
https://en.wikipedia.org/wiki/Weaving
Weaving
Weaving is a method of textile production in which two distinct sets of yarns or threads are interlaced at right angles to form a fabric or cloth. Other methods are knitting, crocheting, felting, and braiding or plaiting. The longitudinal threads are called the warp and the lateral threads are the weft, woof, or filli...
Technology
Techniques_2
null
51971
https://en.wikipedia.org/wiki/Yarn
Yarn
Yarn is a long continuous length of interlocked fibres, used in sewing, crocheting, knitting, weaving, embroidery, ropemaking, and the production of textiles. Thread is a type of yarn intended for sewing by hand or machine. Modern manufactured sewing threads may be finished with wax or other lubricants to withstand the...
Technology
Fabrics and fibers
null
52015
https://en.wikipedia.org/wiki/Proper%20motion
Proper motion
Proper motion is the astrometric measure of the observed changes in the apparent places of stars or other celestial objects in the sky, as seen from the center of mass of the Solar System, compared to the abstract background of the more distant stars. The components for proper motion in the equatorial coordinate syste...
Physical sciences
Basics
Astronomy
52033
https://en.wikipedia.org/wiki/Mathematical%20optimization
Mathematical optimization
Mathematical optimization (alternatively spelled optimisation) or mathematical programming is the selection of a best element, with regard to some criteria, from some set of available alternatives. It is generally divided into two subfields: discrete optimization and continuous optimization. Optimization problems arise...
Mathematics
Other
null
52070
https://en.wikipedia.org/wiki/Arch
Arch
An arch is a curved vertical structure spanning an open space underneath it. Arches may support the load above them, or they may perform a purely decorative role. As a decorative element, the arch dates back to the 4th millennium BC, but structural load-bearing arches became popular only after their adoption by the Anc...
Technology
Architectural elements
null
52080
https://en.wikipedia.org/wiki/Vibrio%20cholerae
Vibrio cholerae
Vibrio cholerae is a species of Gram-negative, facultative anaerobe and comma-shaped bacteria. The bacteria naturally live in brackish or saltwater where they attach themselves easily to the chitin-containing shells of crabs, shrimp, and other shellfish. Some strains of V. cholerae are pathogenic to humans and cause a ...
Biology and health sciences
Gram-negative bacteria
Plants
52081
https://en.wikipedia.org/wiki/Antihydrogen
Antihydrogen
Antihydrogen () is the antimatter counterpart of hydrogen. Whereas the common hydrogen atom is composed of an electron and proton, the antihydrogen atom is made up of a positron and antiproton. Scientists hope that studying antihydrogen may shed light on the question of why there is more matter than antimatter in the o...
Physical sciences
Antimatter
Physics
52082
https://en.wikipedia.org/wiki/Cable%20transport
Cable transport
Cable transport is a broad class of transport modes that have cables. They transport passengers and goods, often in vehicles called cable cars. The cable may be driven or passive, and items may be moved by pulling, sliding, sailing, or by drives within the object being moved on cableways. The use of pulleys and balanci...
Technology
Other
null
52085
https://en.wikipedia.org/wiki/Protein%20folding
Protein folding
Protein folding is the physical process by which a protein, after synthesis by a ribosome as a linear chain of amino acids, changes from an unstable random coil into a more ordered three-dimensional structure. This structure permits the protein to become biologically functional. The folding of many proteins begins eve...
Biology and health sciences
Molecular biology
Biology
52124
https://en.wikipedia.org/wiki/VHS
VHS
VHS (Video Home System) is a standard for consumer-level analog video recording on tape cassettes, introduced in 1976 by the Victor Company of Japan (JVC). It was the dominant home video format throughout the tape media period in the 1980s and 1990s. Magnetic tape video recording was adopted by the television industry...
Technology
Non-volatile memory
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