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22834
https://en.wikipedia.org/wiki/Ozone%20layer
Ozone layer
The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere. The ozone layer contains less than ...
Physical sciences
Atmosphere: General
Earth science
22915
https://en.wikipedia.org/wiki/Planet
Planet
A planet is a large, rounded astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf, and is not one itself. The Solar System has eight planets by the most restrictive definition of the term: the terrestrial planets Mercury, Venus, Earth, and Mars, and the giant planet...
Physical sciences
Astronomy
null
22934
https://en.wikipedia.org/wiki/Probability
Probability
Probability is the branch of mathematics and statistics concerning events and numerical descriptions of how likely they are to occur. The probability of an event is a number between 0 and 1; the larger the probability, the more likely an event is to occur. This number is often expressed as a percentage (%), ranging fr...
Mathematics
Probability and statistics
null
22939
https://en.wikipedia.org/wiki/Physics
Physics
Physics is the scientific study of matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. Physics is one of the most fundamental scientific disciplines. A scientist who specializes in the field of physics is called a physicist. Physics is one...
Physical sciences
Science and medicine
null
22949
https://en.wikipedia.org/wiki/Population
Population
Population is the term typically used to refer to the number of people in a single area. Governments conduct a census to quantify the size of a resident population within a given jurisdiction. The term is also applied to non-human animals, microorganisms, and plants, and has specific uses within such fields as ecology ...
Biology and health sciences
Ecology
null
22958
https://en.wikipedia.org/wiki/Sample%20space
Sample space
In probability theory, the sample space (also called sample description space, possibility space, or outcome space) of an experiment or random trial is the set of all possible outcomes or results of that experiment. A sample space is usually denoted using set notation, and the possible ordered outcomes, or sample point...
Mathematics
Probability
null
22961
https://en.wikipedia.org/wiki/Event%20%28probability%20theory%29
Event (probability theory)
In probability theory, an event is a subset of outcomes of an experiment (a subset of the sample space) to which a probability is assigned. A single outcome may be an element of many different events, and different events in an experiment are usually not equally likely, since they may include very different groups of o...
Mathematics
Probability
null
22984
https://en.wikipedia.org/wiki/Primate
Primate
Primates is an order of mammals, which is further divided into the strepsirrhines, which include lemurs, galagos, and lorisids; and the haplorhines, which include tarsiers and simians (monkeys and apes). Primates arose 74–63 million years ago first from small terrestrial mammals, which adapted for life in tropical fore...
Biology and health sciences
Biology
null
23000
https://en.wikipedia.org/wiki/Polynomial
Polynomial
In mathematics, a polynomial is a mathematical expression consisting of indeterminates (also called variables) and coefficients, that involves only the operations of addition, subtraction, multiplication and exponentiation to nonnegative integer powers, and has a finite number of terms. An example of a polynomial of a ...
Mathematics
Basics
null
23001
https://en.wikipedia.org/wiki/Polymer
Polymer
A polymer () is a substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeating subunits derived from one or more species of monomers. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday l...
Physical sciences
Chemistry: General
null
23015
https://en.wikipedia.org/wiki/Programming%20language
Programming language
A programming language is a system of notation for writing computer programs. Programming languages are described in terms of their syntax (form) and semantics (meaning), usually defined by a formal language. Languages usually provide features such as a type system, variables, and mechanisms for error handling. An impl...
Technology
Programming
null
23048
https://en.wikipedia.org/wiki/Prion
Prion
A prion is a misfolded protein that induces misfolding in normal variants of the same protein, leading to cellular death. Prions are responsible for prion diseases, known as transmissible spongiform encephalopathy (TSEs), which are fatal and transmissible neurodegenerative diseases affecting both humans and animals. T...
Biology and health sciences
Infectious disease
null
23053
https://en.wikipedia.org/wiki/Periodic%20table
Periodic table
The periodic table, also known as the periodic table of the elements, is an ordered arrangement of the chemical elements into rows ("periods") and columns ("groups"). It is an icon of chemistry and is widely used in physics and other sciences. It is a depiction of the periodic law, which states that when the elements a...
Physical sciences
Chemistry
null
23055
https://en.wikipedia.org/wiki/Potassium
Potassium
Potassium is a chemical element; it has symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash...
Physical sciences
Chemical elements_2
null
23084
https://en.wikipedia.org/wiki/Paleontology
Paleontology
Paleontology ( ), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossils to classify organisms and study their interactions with each other and their environments (their pal...
Biology and health sciences
Biology
null
4414414
https://en.wikipedia.org/wiki/Electride
Electride
An electride is an ionic compound in which an electron serves the role of the anion. Solutions of alkali metals in ammonia are electride salts. In the case of sodium, these blue solutions consist of [Na(NH3)6]+ and solvated electrons: Na + 6 NH3 → [Na(NH3)6]+ + e− The cation [Na(NH3)6]+ is an octahedral coordinat...
Physical sciences
Noble gas compounds
Chemistry
18978668
https://en.wikipedia.org/wiki/Pickled%20cucumber
Pickled cucumber
A pickled cucumber – commonly known as a pickle in the United States and Canada and a gherkin ( ) in Britain, Ireland, South Africa, Australia, and New Zealand – is a usually small or miniature cucumber that has been pickled in a brine, vinegar, or other solution and left to ferment. The fermentation process is execute...
Biology and health sciences
Botanical fruits used as culinary vegetables
Plants
18978754
https://en.wikipedia.org/wiki/Apple
Apple
An apple is a round, edible fruit produced by an apple tree (Malus spp., among them the domestic or orchard apple; Malus domestica). Apple trees are cultivated worldwide and are the most widely grown species in the genus Malus. The tree originated in Central Asia, where its wild ancestor, Malus sieversii, is still foun...
Biology and health sciences
Rosales
null
18985040
https://en.wikipedia.org/wiki/Data
Data
Data ( , ) are a collection of discrete or continuous values that convey information, describing the quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted formally. A datum is an individual value in a collection of data. Data are usually orga...
Physical sciences
Science basics
Basics and measurement
12310379
https://en.wikipedia.org/wiki/Saldidae
Saldidae
Saldidae, also known as shore bugs, are a family of insects in the order Hemiptera (true bugs). They are oval-shaped and measure when mature. Typically they are found near shorelines or the marginal growths near freshwater bodies, estuaries, and sea coasts. They can flee by leaping or taking flight. There are about 35...
Biology and health sciences
Hemiptera (true bugs)
Animals
12310667
https://en.wikipedia.org/wiki/Point%20bar
Point bar
A point bar is a depositional feature made of alluvium that accumulates on the inside bend of streams and rivers below the slip-off slope. Point bars are found in abundance in mature or meandering streams. They are crescent-shaped and located on the inside of a stream bend, being very similar to, though often smaller ...
Physical sciences
Fluvial landforms
Earth science
12312178
https://en.wikipedia.org/wiki/Cut%20bank
Cut bank
A cut bank, also known as a river cliff or river-cut cliff, is the outside bank of a curve (meander) in a water channel (stream), which is continually undergoing erosion. Cut banks are found in abundance along mature or meandering streams, they are located opposite the slip-off slope on the inside of the stream meander...
Physical sciences
Fluvial landforms
Earth science
12313191
https://en.wikipedia.org/wiki/Limits%20of%20integration
Limits of integration
In calculus and mathematical analysis the limits of integration (or bounds of integration) of the integral of a Riemann integrable function defined on a closed and bounded interval are the real numbers and , in which is called the lower limit and the upper limit. The region that is bounded can be seen as the area ...
Mathematics
Integral calculus
null
1697945
https://en.wikipedia.org/wiki/Host%E2%80%93guest%20chemistry
Host–guest chemistry
In supramolecular chemistry, host–guest chemistry describes complexes that are composed of two or more molecules or ions that are held together in unique structural relationships by forces other than those of full covalent bonds. Host–guest chemistry encompasses the idea of molecular recognition and interactions throug...
Physical sciences
Supramolecular chemistry
Chemistry
1698977
https://en.wikipedia.org/wiki/Homogeneous%20polynomial
Homogeneous polynomial
In mathematics, a homogeneous polynomial, sometimes called quantic in older texts, is a polynomial whose nonzero terms all have the same degree. For example, is a homogeneous polynomial of degree 5, in two variables; the sum of the exponents in each term is always 5. The polynomial is not homogeneous, because the sum...
Mathematics
Abstract algebra
null
1699025
https://en.wikipedia.org/wiki/Aerial%20application
Aerial application
Aerial application, or what is informally referred to as crop dusting, involves spraying crops with crop protection products from an agricultural aircraft. Planting certain types of seed are also included in aerial application. The specific spreading of fertilizer is also known as aerial topdressing in some countries. ...
Technology
Pest and disease control
null
1699214
https://en.wikipedia.org/wiki/Discrete%20uniform%20distribution
Discrete uniform distribution
In probability theory and statistics, the discrete uniform distribution is a symmetric probability distribution wherein each of some finite whole number n of outcome values are equally likely to be observed. Thus every one of the n outcome values has equal probability 1/n. Intuitively, a discrete uniform distribution i...
Mathematics
Statistics and probability
null
1699223
https://en.wikipedia.org/wiki/Continuous%20uniform%20distribution
Continuous uniform distribution
In probability theory and statistics, the continuous uniform distributions or rectangular distributions are a family of symmetric probability distributions. Such a distribution describes an experiment where there is an arbitrary outcome that lies between certain bounds. The bounds are defined by the parameters, and w...
Mathematics
Probability
null
1701075
https://en.wikipedia.org/wiki/Sequence%20space
Sequence space
In functional analysis and related areas of mathematics, a sequence space is a vector space whose elements are infinite sequences of real or complex numbers. Equivalently, it is a function space whose elements are functions from the natural numbers to the field K of real or complex numbers. The set of all such functio...
Mathematics
Mathematical analysis
null
7657737
https://en.wikipedia.org/wiki/Wet%20lab
Wet lab
A wet lab, or experimental lab, is a type of laboratory where it is necessary to handle various types of chemicals and potential "wet" hazards, so the room has to be carefully designed, constructed, and controlled to avoid spillage and contamination. A dry lab might have large experimental equipment but minimal chemi...
Physical sciences
Basics: General
Chemistry
7661439
https://en.wikipedia.org/wiki/Argon%20fluorohydride
Argon fluorohydride
Argon fluorohydride (systematically named fluoridohydridoargon) or argon hydrofluoride is an inorganic compound with the chemical formula HArF (also written ArHF). It is a compound of the chemical element argon. Discovery The discovery of this argon compound is credited to a group of Finnish scientists, led by Markku...
Physical sciences
Noble gas compounds
Chemistry
670376
https://en.wikipedia.org/wiki/Power-flow%20study
Power-flow study
In power engineering, the power-flow study, or load-flow study, is a numerical analysis of the flow of electric power in an interconnected system. A power-flow study usually uses simplified notations such as a one-line diagram and per-unit system, and focuses on various aspects of AC power parameters, such as Voltage...
Technology
Concepts
null
670765
https://en.wikipedia.org/wiki/Biostratigraphy
Biostratigraphy
Biostratigraphy is the branch of stratigraphy which focuses on correlating and assigning relative ages of rock strata by using the fossil assemblages contained within them. The primary objective of biostratigraphy is correlation, demonstrating that a particular horizon in one geological section represents the same peri...
Physical sciences
Stratigraphy
Earth science
670854
https://en.wikipedia.org/wiki/Jasmonate
Jasmonate
Jasmonate (JA) and its derivatives are lipid-based plant hormones that regulate a wide range of processes in plants, ranging from growth and photosynthesis to reproductive development. In particular, JAs are critical for plant defense against herbivory and plant responses to poor environmental conditions and other kind...
Biology and health sciences
Plant hormone
Biology
670855
https://en.wikipedia.org/wiki/Brassinosteroid
Brassinosteroid
Brassinosteroids (BRs or less commonly BS) are a class of polyhydroxysteroids that have been recognized as a sixth class of plant hormones and may have utility as anticancer drugs for treating endocrine-responsive cancers by inducing apoptosis of cancer cells and inhibiting cancerous growth. These brassinosteroids were...
Biology and health sciences
Plant hormone
Biology
670856
https://en.wikipedia.org/wiki/Abscisic%20acid
Abscisic acid
Abscisic acid (ABA or abscisin II) is a plant hormone. ABA functions in many plant developmental processes, including seed and bud dormancy, the control of organ size and stomatal closure. It is especially important for plants in the response to environmental stresses, including drought, soil salinity, cold tolerance, ...
Biology and health sciences
Plant hormone
Biology
671090
https://en.wikipedia.org/wiki/Cowan%E2%80%93Reines%20neutrino%20experiment
Cowan–Reines neutrino experiment
The Cowan–Reines neutrino experiment was conducted by physicists Clyde Cowan and Frederick Reines in 1956. The experiment confirmed the existence of neutrinos. Neutrinos, subatomic particles with no electric charge and very small mass, had been conjectured to be an essential particle in beta decay processes in the 1930...
Physical sciences
Fermions
Physics
672092
https://en.wikipedia.org/wiki/Drawbridge
Drawbridge
A drawbridge or draw-bridge is a type of moveable bridge typically at the entrance to a castle or tower surrounded by a moat. In some forms of English, including American English, the word drawbridge commonly refers to all types of moveable bridges, such as bascule bridges, vertical-lift bridges and swing bridges, but ...
Technology
Transport infrastructure
null
672202
https://en.wikipedia.org/wiki/Yang%E2%80%93Mills%20theory
Yang–Mills theory
Yang–Mills theory is a quantum field theory for nuclear binding devised by Chen Ning Yang and Robert Mills in 1953, as well as a generic term for the class of similar theories. The Yang–Mills theory is a gauge theory based on a special unitary group , or more generally any compact Lie group. A Yang–Mills theory seeks t...
Physical sciences
Particle physics: General
Physics
672218
https://en.wikipedia.org/wiki/Isospin
Isospin
In nuclear physics and particle physics, isospin (I) is a quantum number related to the up- and down quark content of the particle. Isospin is also known as isobaric spin or isotopic spin. Isospin symmetry is a subset of the flavour symmetry seen more broadly in the interactions of baryons and mesons. The name of the...
Physical sciences
Quantum numbers
Physics
673275
https://en.wikipedia.org/wiki/Scale%20insect
Scale insect
Scale insects are small insects of the order Hemiptera, suborder Sternorrhyncha. Of dramatically variable appearance and extreme sexual dimorphism, they comprise the infraorder Coccomorpha which is considered a more convenient grouping than the superfamily Coccoidea due to taxonomic uncertainties. Adult females typical...
Biology and health sciences
Hemiptera (true bugs)
null
673530
https://en.wikipedia.org/wiki/Balto
Balto
Balto ( – March 14, 1933) was an Alaskan husky and sled dog belonging to musher and breeder Leonhard Seppala. He achieved fame when he led a team of sled dogs driven by Gunnar Kaasen on the final leg of the 1925 serum run to Nome, in which diphtheria antitoxin was transported from Anchorage, Alaska, to Nenana, Alaska, ...
Biology and health sciences
Individual animals
Animals
673743
https://en.wikipedia.org/wiki/Craton
Craton
A craton ( , , or ; from "strength") is an old and stable part of the continental lithosphere, which consists of Earth's two topmost layers, the crust and the uppermost mantle. Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates; the exc...
Physical sciences
Tectonics
Earth science
673768
https://en.wikipedia.org/wiki/Continental%20crust
Continental crust
Continental crust is the layer of igneous, metamorphic, and sedimentary rocks that forms the geological continents and the areas of shallow seabed close to their shores, known as continental shelves. This layer is sometimes called sial because its bulk composition is richer in aluminium silicates (Al-Si) and has a lowe...
Physical sciences
Tectonics
Earth science
673880
https://en.wikipedia.org/wiki/S%C3%A3o%20Paulo%20Metro
São Paulo Metro
The São Paulo Metro (, ), commonly called the Metrô, is a rapid transit system that forms part of the urban railways that serves the city of São Paulo, alongside the São Paulo Metropolitan Trains Company (CPTM), both forming the largest metropolitan rail transport network of Latin America. The six lines in the metro sy...
Technology
Brazil
null
673887
https://en.wikipedia.org/wiki/Reticle
Reticle
A reticle, or reticule also known as a graticule, is a pattern of fine lines or markings built into the eyepiece of an optical device such as a telescopic sight, spotting scope, theodolite, optical microscope or the screen of an oscilloscope, to provide measurement references during visual inspections. Today, engraved ...
Technology
Surveying tools
null
674050
https://en.wikipedia.org/wiki/Picard%20theorem
Picard theorem
In complex analysis, Picard's great theorem and Picard's little theorem are related theorems about the range of an analytic function. They are named after Émile Picard. The theorems Little Picard Theorem: If a function is entire and non-constant, then the set of values that assumes is either the whole complex plan...
Mathematics
Complex analysis
null
674207
https://en.wikipedia.org/wiki/Torso
Torso
The torso or trunk is an anatomical term for the central part, or the core, of the body of many animals (including human beings), from which the head, neck, limbs, tail and other appendages extend. The tetrapod torso — including that of a human — is usually divided into the thoracic segment (also known as the upper tor...
Biology and health sciences
External anatomy and regions of the body
Biology
13947297
https://en.wikipedia.org/wiki/Buttocks
Buttocks
The buttocks (: buttock) are two rounded portions of the exterior anatomy of most mammals, located on the posterior of the pelvic region. In humans, the buttocks are located between the lower back and the perineum. They are composed of a layer of exterior skin and underlying subcutaneous fat superimposed on a left and ...
Biology and health sciences
External anatomy and regions of the body
Biology
2367035
https://en.wikipedia.org/wiki/Cumulus%20congestus%20cloud
Cumulus congestus cloud
Cumulus congestus or towering cumulus clouds are a species of cumulus that can be based in the low- to middle-height ranges. They achieve considerable vertical development in areas of deep, moist convection. They are an intermediate stage between cumulus mediocris and cumulonimbus, sometimes producing rainshowers, snow...
Physical sciences
Clouds
Earth science
2367828
https://en.wikipedia.org/wiki/Tin%28IV%29%20oxide
Tin(IV) oxide
Tin(IV) oxide, also known as stannic oxide, is the inorganic compound with the formula SnO2. The mineral form of SnO2 is called cassiterite, and this is the main ore of tin. With many other names, this oxide of tin is an important material in tin chemistry. It is a colourless, diamagnetic, amphoteric solid. Structure ...
Physical sciences
Oxide salts
Chemistry
3254510
https://en.wikipedia.org/wiki/Scala%20%28programming%20language%29
Scala (programming language)
Scala ( ) is a strong statically typed high-level general-purpose programming language that supports both object-oriented programming and functional programming. Designed to be concise, many of Scala's design decisions are intended to address criticisms of Java. Scala source code can be compiled to Java bytecode and r...
Technology
Programming languages
null
3255917
https://en.wikipedia.org/wiki/Transmission%20system%20operator
Transmission system operator
A transmission system operator (TSO) is an entity entrusted with transporting energy in the form of natural gas or electrical power on a national or regional level, using fixed infrastructure. The term is defined by the European Commission. The certification procedure for transmission system operators is listed in Arti...
Technology
Electricity transmission and distribution
null
201605
https://en.wikipedia.org/wiki/Sampling%20%28signal%20processing%29
Sampling (signal processing)
In signal processing, sampling is the reduction of a continuous-time signal to a discrete-time signal. A common example is the conversion of a sound wave to a sequence of "samples". A sample is a value of the signal at a point in time and/or space; this definition differs from the term's usage in statistics, which refe...
Technology
Signal processing
null
201629
https://en.wikipedia.org/wiki/Gradian
Gradian
In trigonometry, the gradianalso known as the gon (), grad, or gradeis a unit of measurement of an angle, defined as one-hundredth of the right angle; in other words, 100 gradians is equal to 90 degrees. It is equivalent to of a turn, of a degree, or of a radian. Measuring angles in gradians (gons) is said to employ...
Physical sciences
Angle
Basics and measurement
201635
https://en.wikipedia.org/wiki/Cinereous%20vulture
Cinereous vulture
The cinereous vulture (Aegypius monachus) is a large raptor in the family Accipitridae and distributed through much of temperate Eurasia. It is also known as the black vulture, monk vulture and Eurasian black vulture. With a body length of , across the wings and a maximum weight of , it is the largest Old World vultur...
Biology and health sciences
Accipitrimorphae
Animals
201657
https://en.wikipedia.org/wiki/Scientific%20evidence
Scientific evidence
Scientific evidence is evidence that serves to either support or counter a scientific theory or hypothesis, although scientists also use evidence in other ways, such as when applying theories to practical problems. Such evidence is expected to be empirical evidence and interpretable in accordance with the scientific me...
Physical sciences
Science basics
Basics and measurement
201676
https://en.wikipedia.org/wiki/Stationery
Stationery
Stationery refers to writing materials, including cut paper, envelopes, continuous form paper, and other office supplies. Stationery usually specifies materials to be written on by hand (e.g., letter paper) or by equipment such as computer printers. History of stationery Originally, the term 'stationery' referred to a...
Technology
Media and communication: Basics
null
201689
https://en.wikipedia.org/wiki/Polypropylene
Polypropylene
Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer propylene. Polypropylene belongs to the group of polyolefins and is partially crystalline and non-polar. Its properties are similar to polyet...
Physical sciences
Hydrocarbons
null
201716
https://en.wikipedia.org/wiki/Lithium%20polymer%20battery
Lithium polymer battery
A lithium polymer battery, or more correctly, lithium-ion polymer battery (abbreviated as LiPo, LIP, Li-poly, lithium-poly, and others), is a rechargeable battery of lithium-ion technology using a polymer electrolyte instead of a liquid electrolyte. Highly conductive semisolid (gel) polymers form this electrolyte. Thes...
Technology
Energy storage
null
201826
https://en.wikipedia.org/wiki/Trapezoid
Trapezoid
In geometry, a trapezoid () in North American English, or trapezium () in British English, is a quadrilateral that has one pair of parallel sides. The parallel sides are called the bases of the trapezoid. The other two sides are called the legs (or the lateral sides) if they are not parallel; otherwise, the trapezoid ...
Mathematics
Two-dimensional space
null
201943
https://en.wikipedia.org/wiki/Bird%20migration
Bird migration
Bird migration is a seasonal movement of birds between breeding and wintering grounds that occurs twice a year. It is typically from north to south or from south to north. Migration is inherently risky, due to predation and mortality. The Arctic tern holds the long-distance migration record for birds, travelling betwe...
Biology and health sciences
Ethology
Biology
201951
https://en.wikipedia.org/wiki/European%20honey%20buzzard
European honey buzzard
The European honey buzzard (Pernis apivorus), also known as the pern or common pern, is a bird of prey in the family Accipitridae. Taxonomy The European honey buzzard was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae. He placed it with the falcons and ea...
Biology and health sciences
Accipitrimorphae
Animals
201968
https://en.wikipedia.org/wiki/Synapsida
Synapsida
Synapsida is a diverse group of tetrapod vertebrates that includes all mammals and their extinct relatives. It is one of the two major clades of the group Amniota, the other being the more diverse group Sauropsida (which includes all extant reptiles and birds). Unlike other amniotes, synapsids have a single temporal fe...
Biology and health sciences
Dinosaurs and prehistoric reptiles
null
201983
https://en.wikipedia.org/wiki/Coronavirus
Coronavirus
Coronaviruses are a group of related RNA viruses that cause diseases in mammals and birds. In humans and birds, they cause respiratory tract infections that can range from mild to lethal. Mild illnesses in humans include some cases of the common cold (which is also caused by other viruses, predominantly rhinoviruses), ...
Biology and health sciences
Infectious disease
null
202240
https://en.wikipedia.org/wiki/Bivalvia
Bivalvia
Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed by a calcified exoskeleton consisting of a hinged pair of half-shells known as valves. As a group, bivalves have ...
Biology and health sciences
Bivalvia
Animals
202388
https://en.wikipedia.org/wiki/Spear-thrower
Spear-thrower
A spear-thrower, spear-throwing lever, or atlatl (pronounced or ; Nahuatl ahtlatl ) is a tool that uses leverage to achieve greater velocity in dart or javelin-throwing, and includes a bearing surface that allows the user to store energy during the throw. It may consist of a shaft with a cup or a spur at the end that...
Technology
Ranged weapons
null
202403
https://en.wikipedia.org/wiki/Excavata
Excavata
Excavata is an extensive and diverse but paraphyletic group of unicellular Eukaryota. The group was first suggested by Simpson and Patterson in 1999 and the name latinized and assigned a rank by Thomas Cavalier-Smith in 2002. It contains a variety of free-living and symbiotic protists, and includes some important paras...
Biology and health sciences
Other organisms
null
202482
https://en.wikipedia.org/wiki/Foot%20%28unit%29
Foot (unit)
The foot (standard symbol: ft) is a unit of length in the British imperial and United States customary systems of measurement. The prime symbol, , is commonly used to represent the foot. In both customary and imperial units, one foot comprises 12 inches, and one yard comprises three feet. Since an international agreeme...
Physical sciences
Length and distance
null
202497
https://en.wikipedia.org/wiki/Waxwing
Waxwing
The waxwings are three species of passerine birds classified in the genus Bombycilla. They are pinkish-brown and pale grey with distinctive smooth plumage in which many body feathers are not individually visible, a black and white eyestripe, a crest, a square-cut tail and pointed wings. Some of the wing feathers have r...
Biology and health sciences
Passerida
Animals
202522
https://en.wikipedia.org/wiki/Ionizing%20radiation
Ionizing radiation
Ionizing radiation (US, ionising radiation in the UK), including nuclear radiation, consists of subatomic particles or electromagnetic waves that have sufficient energy to ionize atoms or molecules by detaching electrons from them. Some particles can travel up to 99% of the speed of light, and the electromagnetic waves...
Physical sciences
Basics_6
null
202661
https://en.wikipedia.org/wiki/Stellar%20parallax
Stellar parallax
Stellar parallax is the apparent shift of position (parallax) of any nearby star (or other object) against the background of distant stars. By extension, it is a method for determining the distance to the star through trigonometry, the stellar parallax method. Created by the different orbital positions of Earth, the ex...
Physical sciences
Basics
Astronomy
202672
https://en.wikipedia.org/wiki/Spectral%20density
Spectral density
In signal processing, the power spectrum of a continuous time signal describes the distribution of power into frequency components composing that signal. According to Fourier analysis, any physical signal can be decomposed into a number of discrete frequencies, or a spectrum of frequencies over a continuous range. ...
Physical sciences
Electromagnetic radiation
Physics
202696
https://en.wikipedia.org/wiki/Marina
Marina
A marina (from Spanish , Portuguese and Italian : "related to the sea") is a dock or basin with moorings and supplies for yachts and small boats. A marina differs from a port in that a marina does not handle large passenger ships or cargo from freighters. The word marina may also refer to an inland wharf on a river o...
Technology
Coastal infrastructure
null
202898
https://en.wikipedia.org/wiki/Atmosphere%20of%20Earth
Atmosphere of Earth
The atmosphere of Earth is composed of a layer of gas mixture that surrounds the Earth's planetary surface (both lands and oceans), known collectively as air, with variable quantities of suspended aerosols and particulates (which create weather features such as clouds and hazes), all retained by Earth's gravity. The at...
Physical sciences
Earth science
null
202899
https://en.wikipedia.org/wiki/Atmosphere
Atmosphere
An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosphere is the outer region of a star, which includes the layers above the opaque phot...
Physical sciences
Planetary science
null
203056
https://en.wikipedia.org/wiki/Spherical%20harmonics
Spherical harmonics
In mathematics and physical science, spherical harmonics are special functions defined on the surface of a sphere. They are often employed in solving partial differential equations in many scientific fields. The table of spherical harmonics contains a list of common spherical harmonics. Since the spherical harmonics f...
Physical sciences
Atomic physics
Physics
203082
https://en.wikipedia.org/wiki/Temperate%20coniferous%20forest
Temperate coniferous forest
Temperate coniferous forest is a terrestrial biome defined by the World Wide Fund for Nature. Temperate coniferous forests are found predominantly in areas with warm summers and cool winters, and vary in their kinds of plant life. In some, needleleaf trees dominate, while others are home primarily to broadleaf evergree...
Physical sciences
Forests
Earth science
203085
https://en.wikipedia.org/wiki/Tropical%20and%20subtropical%20grasslands%2C%20savannas%2C%20and%20shrublands
Tropical and subtropical grasslands, savannas, and shrublands
Tropical and subtropical grasslands, savannas, and shrublands is a terrestrial biome defined by the World Wide Fund for Nature. The biome is dominated by grass and/or shrubs located in semi-arid to semi-humid climate regions of subtropical and tropical latitudes. Tropical grasslands are mainly found between 5 degrees a...
Physical sciences
Grasslands
Earth science
203089
https://en.wikipedia.org/wiki/Flooded%20grasslands%20and%20savannas
Flooded grasslands and savannas
Flooded grasslands and savannas is a terrestrial biome of the World Wide Fund for Nature (WWF) biogeographical system, consisting of large expanses or complexes of flooded grasslands. These areas support numerous plants and animals adapted to the unique hydrologic regimes and soil conditions. Large congregations of mig...
Physical sciences
Wetlands
Earth science
203103
https://en.wikipedia.org/wiki/Montane%20grasslands%20and%20shrublands
Montane grasslands and shrublands
Montane grasslands and shrublands are a biome defined by the World Wildlife Fund. The biome includes high elevation grasslands and shrublands around the world. The term "montane" in the name of the biome refers to "high elevation", rather than the ecological term that denotes the region below the treeline. This biome ...
Physical sciences
Grasslands
Earth science
203104
https://en.wikipedia.org/wiki/Alpine%20tundra
Alpine tundra
Alpine tundra is a type of natural region or biome that does not contain trees because it is at high elevation, with an associated harsh climate. As the latitude of a location approaches the poles, the threshold elevation for alpine tundra gets lower until it reaches sea level, and alpine tundra merges with polar tundr...
Physical sciences
Biomes: General
Earth science
203109
https://en.wikipedia.org/wiki/Temperate%20broadleaf%20and%20mixed%20forests
Temperate broadleaf and mixed forests
Temperate broadleaf and mixed forest is a temperate climate terrestrial habitat type defined by the World Wide Fund for Nature, with broadleaf tree ecoregions, and with conifer and broadleaf tree mixed coniferous forest ecoregions. These forests are richest and most distinctive in central China and eastern North Amer...
Physical sciences
Forests
null
203111
https://en.wikipedia.org/wiki/Tropical%20and%20subtropical%20coniferous%20forests
Tropical and subtropical coniferous forests
Tropical and subtropical coniferous forests are a tropical forest habitat type defined by the World Wide Fund for Nature. These forests are found predominantly in North and Central America and experience low levels of precipitation and moderate variability in temperature. Tropical and subtropical coniferous forests are...
Physical sciences
Forests
Earth science
203113
https://en.wikipedia.org/wiki/Tropical%20and%20subtropical%20dry%20broadleaf%20forests
Tropical and subtropical dry broadleaf forests
The tropical and subtropical dry broadleaf forest is a habitat type defined by the World Wide Fund for Nature and is located at tropical and subtropical latitudes. Though these forests occur in climates that are warm year-round, and may receive several hundred millimeters of rain per year, they have long dry seasons t...
Physical sciences
Forests
Earth science
203115
https://en.wikipedia.org/wiki/Tropical%20and%20subtropical%20moist%20broadleaf%20forests
Tropical and subtropical moist broadleaf forests
Tropical and subtropical moist broadleaf forests (TSMF), also known as tropical moist forest, is a subtropical and tropical forest habitat type defined by the World Wide Fund for Nature. Description TSMF is generally found in large, discontinuous patches centered on the equatorial belt and between the Tropic of Canc...
Physical sciences
Forests
Earth science
203116
https://en.wikipedia.org/wiki/Vulpes
Vulpes
Vulpes is a genus of the sub-family Caninae. The members of this genus are colloquially referred to as true foxes, meaning they form a proper clade. The word "fox" occurs in the common names of all species of the genus, but also appears in the common names of other canid species. True foxes are distinguished from memb...
Biology and health sciences
Canines
Animals
203200
https://en.wikipedia.org/wiki/Quark%20star
Quark star
A quark star is a hypothetical type of compact, exotic star, where extremely high core temperature and pressure have forced nuclear particles to form quark matter, a continuous state of matter consisting of free quarks. Background Some massive stars collapse to form neutron stars at the end of their life cycle, as h...
Physical sciences
Stellar astronomy
Astronomy
203314
https://en.wikipedia.org/wiki/W.%20M.%20Keck%20Observatory
W. M. Keck Observatory
The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state of Hawaii. Both telescopes have aperture primary mirrors, and, when completed in 1993 (Keck I) and 1996 (Keck II), they were the largest optical refle...
Technology
Ground-based observatories
null
203318
https://en.wikipedia.org/wiki/Ritchey%E2%80%93Chr%C3%A9tien%20telescope
Ritchey–Chrétien telescope
A Ritchey–Chrétien telescope (RCT or simply RC) is a specialized variant of the Cassegrain telescope that has a hyperbolic primary mirror and a hyperbolic secondary mirror designed to eliminate off-axis optical errors (coma). The RCT has a wider field of view free of optical errors compared to a more traditional reflec...
Technology
Telescope
null
203359
https://en.wikipedia.org/wiki/Magnetic%20resonance
Magnetic resonance
Magnetic resonance is a process by which a physical excitation (resonance) is set up via magnetism. This process was used to develop magnetic resonance imaging (MRI) and nuclear magnetic resonance spectroscopy (NMRS) technology. It is also being used to develop nuclear magnetic resonance quantum computers. History ...
Physical sciences
Nuclear physics
Physics
203545
https://en.wikipedia.org/wiki/Nuthatch
Nuthatch
The nuthatches () constitute a genus, Sitta, of small passerine birds belonging to the family Sittidae. Characterised by large heads, short tails, and powerful bills and feet, nuthatches advertise their territory using loud, simple songs. Most species exhibit grey or bluish upper parts and a black eye stripe. Most nut...
Biology and health sciences
Passerida
Animals
203847
https://en.wikipedia.org/wiki/Buteo
Buteo
Buteo is a genus of medium to fairly large, wide-ranging raptors with a robust body and broad wings. In the Old World, members of this genus are called "buzzards", but "hawk" is used in the New World (Etymology: Buteo is the Latin name of the common buzzard). As both terms are ambiguous, buteo is sometimes used instea...
Biology and health sciences
Accipitrimorphae
Animals
203859
https://en.wikipedia.org/wiki/Wallcreeper
Wallcreeper
The wallcreeper (Tichodroma muraria) is a small passerine bird found throughout the high mountains of the Palearctic from southern Europe to central China. It is the only extant member of both the genus Tichodroma and the family Tichodromidae. Taxonomy and systematics In the past, there was some disagreement among orn...
Biology and health sciences
Passerida
Animals
203896
https://en.wikipedia.org/wiki/Adobe%20Acrobat
Adobe Acrobat
Adobe Acrobat is a family of application software and web services developed by Adobe Inc. to view, create, manipulate, print and manage Portable Document Format (PDF) files. The family comprises Acrobat Reader (formerly Reader), Acrobat (formerly Exchange) and Acrobat.com. The basic Acrobat Reader, available for seve...
Technology
Office and data management
null
203921
https://en.wikipedia.org/wiki/Crusher
Crusher
A crusher is a machine designed to reduce large rocks into smaller rocks, gravel, sand or rock dust. Crushers may be used to reduce the size, or change the form, of waste materials so they can be more easily disposed of or recycled, or to reduce the size of a solid mix of raw materials (as in rock ore), so that pieces...
Technology
Metallurgy
null
203970
https://en.wikipedia.org/wiki/Hoopoe
Hoopoe
Hoopoes () are colourful birds found across Africa, Asia, and Europe, notable for their distinctive "crown" of feathers which can be raised or lowered at will. Three living and one extinct species are recognized, though for many years all of the extant species were lumped as a single species—Upupa epops. In fact, some ...
Biology and health sciences
Coraciiformes
null
204002
https://en.wikipedia.org/wiki/Directed%20acyclic%20graph
Directed acyclic graph
In mathematics, particularly graph theory, and computer science, a directed acyclic graph (DAG) is a directed graph with no directed cycles. That is, it consists of vertices and edges (also called arcs), with each edge directed from one vertex to another, such that following those directions will never form a closed lo...
Mathematics
Graph theory
null
204037
https://en.wikipedia.org/wiki/3C%20273
3C 273
3C 273 is a quasar located at the center of a giant elliptical galaxy in the constellation of Virgo. It was the first quasar ever to be identified and is the visually brightest quasar in the sky as seen from Earth, with an apparent visual magnitude of 12.9. The derived distance to this object is . The mass of its centr...
Physical sciences
Other notable objects
null
204092
https://en.wikipedia.org/wiki/Therapsida
Therapsida
Therapsida is a clade comprising a major group of eupelycosaurian synapsids that includes mammals and their ancestors and close relatives. Many of the traits today seen as unique to mammals had their origin within early therapsids, including limbs that were oriented more underneath the body, resulting in a more "standi...
Biology and health sciences
Proto-mammals
Animals