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During critical illness, a state of adrenal insufficiency and tissue resistance to corticosteroids may occur. This has been termed critical illness–related corticosteroid insufficiency. Treatment with corticosteroids might be most beneficial in those with septic shock and early severe ARDS, whereas its role in others s... | Sepsis | Wikipedia | 418 | 158400 | https://en.wikipedia.org/wiki/Sepsis | Biology and health sciences | Symptoms and signs | Health |
General anesthesia is recommended for people with sepsis who require surgical procedures to remove the infective source. Usually, inhalational and intravenous anesthetics are used. Requirements for anesthetics may be reduced in sepsis. Inhalational anesthetics can reduce the level of proinflammatory cytokines, altering... | Sepsis | Wikipedia | 353 | 158400 | https://en.wikipedia.org/wiki/Sepsis | Biology and health sciences | Symptoms and signs | Health |
Early goal directed therapy
Early goal directed therapy (EGDT) is an approach to the management of severe sepsis during the initial 6 hours after diagnosis. It is a step-wise approach, with the physiologic goal of optimizing cardiac preload, afterload, and contractility. It includes giving early antibiotics. EGDT also... | Sepsis | Wikipedia | 497 | 158400 | https://en.wikipedia.org/wiki/Sepsis | Biology and health sciences | Symptoms and signs | Health |
Recombinant activated protein C (drotrecogin alpha) was originally introduced for severe sepsis (as identified by a high APACHE II score), where it was thought to confer a survival benefit. However, subsequent studies showed that it increased adverse events—bleeding risk in particular—and did not decrease mortality. It... | Sepsis | Wikipedia | 168 | 158400 | https://en.wikipedia.org/wiki/Sepsis | Biology and health sciences | Symptoms and signs | Health |
Intermittent or continuous renal replacement therapy may be used if indicated. However, sodium bicarbonate is not recommended for a person with lactic acidosis secondary to hypoperfusion. Low-molecular-weight heparin (LMWH), unfractionated heparin (UFH), and mechanical prophylaxis with intermittent pneumatic compressio... | Sepsis | Wikipedia | 505 | 158400 | https://en.wikipedia.org/wiki/Sepsis | Biology and health sciences | Symptoms and signs | Health |
There are a number of prognostic stratification systems, such as APACHE II and Mortality in Emergency Department Sepsis. APACHE II factors in the person's age, underlying condition, and various physiologic variables to yield estimates of the risk of dying of severe sepsis. Of the individual covariates, the severity of ... | Sepsis | Wikipedia | 505 | 158400 | https://en.wikipedia.org/wiki/Sepsis | Biology and health sciences | Symptoms and signs | Health |
Several medical conditions increase a person's susceptibility to infection and developing sepsis. Common sepsis risk factors include age (especially the very young and old); conditions that weaken the immune system such as cancer, diabetes, or the absence of a spleen; and major trauma and burns.
From 1979 to 2000, dat... | Sepsis | Wikipedia | 389 | 158400 | https://en.wikipedia.org/wiki/Sepsis | Biology and health sciences | Symptoms and signs | Health |
The terms "septicemia", also spelled "septicaemia", and "blood poisoning" referred to the microorganisms or their toxins in the blood. The International Statistical Classification of Diseases and Related Health Problems (ICD) version 9, which was in use in the US until 2013, used the term septicemia with numerous modif... | Sepsis | Wikipedia | 488 | 158400 | https://en.wikipedia.org/wiki/Sepsis | Biology and health sciences | Symptoms and signs | Health |
Controversy occurred in the scientific community over the use of mouse models in research into sepsis in 2013 when scientists published a review of the mouse immune system compared to the human immune system and showed that on a systems level, the two worked very differently; the authors noted that as of the date of th... | Sepsis | Wikipedia | 374 | 158400 | https://en.wikipedia.org/wiki/Sepsis | Biology and health sciences | Symptoms and signs | Health |
Some authors suggest that initiating sepsis by the normally mutualistic (or neutral) members of the microbiome may not always be an accidental side effect of the deteriorating host immune system. Rather it is often an adaptive microbial response to a sudden decline of host survival chances. Under this scenario, the mic... | Sepsis | Wikipedia | 375 | 158400 | https://en.wikipedia.org/wiki/Sepsis | Biology and health sciences | Symptoms and signs | Health |
Iron(II) sulfate (British English: iron(II) sulphate) or ferrous sulfate denotes a range of salts with the formula FeSO4·xH2O. These compounds exist most commonly as the heptahydrate (x = 7) but several values for x are known. The hydrated form is used medically to treat or prevent iron deficiency, and also for industr... | Iron(II) sulfate | Wikipedia | 436 | 158405 | https://en.wikipedia.org/wiki/Iron%28II%29%20sulfate | Physical sciences | Sulfuric oxyanions | Chemistry |
In horticulture it is used for treating iron chlorosis. Although not as rapid-acting as ferric EDTA, its effects are longer-lasting. It can be mixed with compost and dug into the soil to create a store which can last for years. Ferrous sulfate can be used as a lawn conditioner. It can also be used to eliminate silvery ... | Iron(II) sulfate | Wikipedia | 400 | 158405 | https://en.wikipedia.org/wiki/Iron%28II%29%20sulfate | Physical sciences | Sulfuric oxyanions | Chemistry |
Hydrates
Iron(II) sulfate can be found in various states of hydration, and several of these forms exist in nature or were created synthetically.
FeSO4·H2O (mineral: szomolnokite, relatively rare, monoclinic)
FeSO4·H2O (synthetic compound stable at pressures exceeding 6.2 GPa, triclinic)
FeSO4·4H2O (mineral: rozenite... | Iron(II) sulfate | Wikipedia | 478 | 158405 | https://en.wikipedia.org/wiki/Iron%28II%29%20sulfate | Physical sciences | Sulfuric oxyanions | Chemistry |
On heating, iron(II) sulfate first loses its water of crystallization and the original green crystals are converted into a white anhydrous solid. When further heated, the anhydrous material decomposes into sulfur dioxide and sulfur trioxide, leaving a reddish-brown iron(III) oxide. Thermolysis of iron(II) sulfate begin... | Iron(II) sulfate | Wikipedia | 199 | 158405 | https://en.wikipedia.org/wiki/Iron%28II%29%20sulfate | Physical sciences | Sulfuric oxyanions | Chemistry |
A Cepheid variable () is a type of variable star that pulsates radially, varying in both diameter and temperature. It changes in brightness, with a well-defined stable period and amplitude. Cepheids are important cosmic benchmarks for scaling galactic and extragalactic distances; a strong direct relationship exists bet... | Cepheid variable | Wikipedia | 379 | 158530 | https://en.wikipedia.org/wiki/Cepheid%20variable | Physical sciences | Stellar astronomy | null |
On September 10, 1784, Edward Pigott detected the variability of Eta Aquilae, the first known representative of the class of classical Cepheid variables. The eponymous star for classical Cepheids, Delta Cephei, was discovered to be variable by John Goodricke a few months later. The number of similar variables grew to s... | Cepheid variable | Wikipedia | 498 | 158530 | https://en.wikipedia.org/wiki/Cepheid%20variable | Physical sciences | Stellar astronomy | null |
In the mid 20th century, significant problems with the astronomical distance scale were resolved by dividing the Cepheids into different classes with very different properties. In the 1940s, Walter Baade recognized two separate populations of Cepheids (classical and type II). Classical Cepheids are younger and more mas... | Cepheid variable | Wikipedia | 402 | 158530 | https://en.wikipedia.org/wiki/Cepheid%20variable | Physical sciences | Stellar astronomy | null |
Classical Cepheids (also known as Population I Cepheids, type I Cepheids, or Delta Cepheid variables) undergo pulsations with very regular periods on the order of days to months. Classical Cepheids are Population I variable stars which are 4–20 times more massive than the Sun, and up to 100,000 times more luminous. The... | Cepheid variable | Wikipedia | 411 | 158530 | https://en.wikipedia.org/wiki/Cepheid%20variable | Physical sciences | Stellar astronomy | null |
Anomalous Cepheids
A group of pulsating stars on the instability strip have periods of less than 2 days, similar to RR Lyrae variables but with higher luminosities. Anomalous Cepheid variables have masses higher than type II Cepheids, RR Lyrae variables, and the Sun. It is unclear whether they are young stars on a "tu... | Cepheid variable | Wikipedia | 365 | 158530 | https://en.wikipedia.org/wiki/Cepheid%20variable | Physical sciences | Stellar astronomy | null |
Delta Cephei is also of particular importance as a calibrator of the Cepheid period-luminosity relation since its distance is among the most precisely established for a Cepheid, partly because it is a member of a star cluster and the availability of precise parallaxes observed by the Hubble, Hipparcos, and Gaia space t... | Cepheid variable | Wikipedia | 488 | 158530 | https://en.wikipedia.org/wiki/Cepheid%20variable | Physical sciences | Stellar astronomy | null |
In 1879, August Ritter (1826–1908) demonstrated that the adiabatic radial pulsation period for a homogeneous sphere is related to its surface gravity and radius through the relation:
where k is a proportionality constant. Now, since the surface gravity is related to the sphere mass and radius through the relation:
on... | Cepheid variable | Wikipedia | 170 | 158530 | https://en.wikipedia.org/wiki/Cepheid%20variable | Physical sciences | Stellar astronomy | null |
An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Aircraft using power components are referred to as powered flight. Most aircraft engines are either piston engines or gas turbines, although a few have been rocket powered and in recent years many small UAV... | Aircraft engine | Wikipedia | 181 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
1848: John Stringfellow made a steam engine for a 10-foot wingspan model aircraft which achieved the first powered flight, albeit with negligible payload.
1903: Charlie Taylor built an inline engine, mostly of aluminum, for the Wright Flyer (12 horsepower).
1903: Manly-Balzer engine sets standards for later radial en... | Aircraft engine | Wikipedia | 500 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
1940: Jendrassik Cs-1, the world's first run of a turboprop engine. It is not put into service.
1943 Daimler-Benz DB 670, first turbofan runs
1944: Messerschmitt Me 163B Komet, the world's first rocket-propelled combat aircraft deployed.
1945: First turboprop-powered aircraft flies, a modified Gloster Meteor with tw... | Aircraft engine | Wikipedia | 276 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
Shaft engines
Reciprocating (piston) engines
In-line engine
In this section, for clarity, the term "inline engine" refers only to engines with a single row of cylinders, as used in automotive language, but in aviation terms, the phrase "inline engine" also covers V-type and opposed engines (as described below), and ... | Aircraft engine | Wikipedia | 459 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
A horizontally opposed engine, also called a flat or boxer engine, has two banks of cylinders on opposite sides of a centrally located crankcase. The engine is either air-cooled or liquid-cooled, but air-cooled versions predominate. Opposed engines are mounted with the crankshaft horizontal in airplanes, but may be mou... | Aircraft engine | Wikipedia | 500 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
In military aircraft designs, the large frontal area of the engine acted as an extra layer of armor for the pilot. Also air-cooled engines, without vulnerable radiators, are slightly less prone to battle damage, and on occasion would continue running even with one or more cylinders shot away. However, the large frontal... | Aircraft engine | Wikipedia | 392 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
The Wankel is a type of rotary engine. The Wankel engine is about one half the weight and size of a traditional four-stroke cycle piston engine of equal power output, and much lower in complexity. In an aircraft application, the power-to-weight ratio is very important, making the Wankel engine a good choice. Because th... | Aircraft engine | Wikipedia | 497 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
Starting in the 1930s attempts were made to produce a practical aircraft diesel engine. In general, Diesel engines are more reliable and much better suited to running for long periods of time at medium power settings. The lightweight alloys of the 1930s were not up to the task of handling the much higher compression ra... | Aircraft engine | Wikipedia | 409 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
Turboshaft engines are used primarily for helicopters and auxiliary power units. A turboshaft engine is similar to a turboprop in principle, but in a turboprop the propeller is supported by the engine and the engine is bolted to the airframe: in a turboshaft, the engine does not provide any direct physical support to t... | Aircraft engine | Wikipedia | 481 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
A turbojet is a type of gas turbine engine that was originally developed for military fighters during World War II. A turbojet is the simplest of all aircraft gas turbines. It consists of a compressor to draw air in and compress it, a combustion section where fuel is added and ignited, one or more turbines that extract... | Aircraft engine | Wikipedia | 247 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
A turbofan engine is much the same as a turbojet, but with an enlarged fan at the front that provides thrust in much the same way as a ducted propeller, resulting in improved fuel efficiency. Though the fan creates thrust like a propeller, the surrounding duct frees it from many of the restrictions that limit propeller... | Aircraft engine | Wikipedia | 425 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
Pulsejets are mechanically simple devices that—in a repeating cycle—draw air through a no-return valve at the front of the engine into a combustion chamber and ignite it. The combustion forces the exhaust gases out the back of the engine. It produces power as a series of pulses rather than as a steady output, hence the... | Aircraft engine | Wikipedia | 504 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
It is thought that this design of engine could permit sufficient performance for antipodal flight at Mach 5, or even permit a single stage to orbit vehicle to be practical. The hybrid air-breathing SABRE rocket engine is a pre-cooled engine under development.
Piston-turbofan hybrid
At the April 2018 ILA Berlin Air Sh... | Aircraft engine | Wikipedia | 494 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
Fuel
Aircraft reciprocating (piston) engines are typically designed to run on aviation gasoline. Avgas has a higher octane rating than automotive gasoline to allow higher compression ratios, power output, and efficiency at higher altitudes. Currently the most common Avgas is 100LL. This refers to the octane rating (100... | Aircraft engine | Wikipedia | 284 | 158681 | https://en.wikipedia.org/wiki/Aircraft%20engine | Technology | Aviation | null |
For organic chemistry, a carbonyl group is a functional group with the formula , composed of a carbon atom double-bonded to an oxygen atom, and it is divalent at the C atom. It is common to several classes of organic compounds (such as aldehydes, ketones and carboxylic acids), as part of many larger functional groups. ... | Carbonyl group | Wikipedia | 467 | 158788 | https://en.wikipedia.org/wiki/Carbonyl%20group | Physical sciences | Concepts: General | Chemistry |
The polarity of C=O bond also enhances the acidity of any adjacent C-H bonds. Due to the positive charge on carbon and the negative charge on oxygen, carbonyl groups are subject to additions and/or nucleophilic attacks. A variety of nucleophiles attack, breaking the carbon-oxygen double bond, and leading to addition-e... | Carbonyl group | Wikipedia | 283 | 158788 | https://en.wikipedia.org/wiki/Carbonyl%20group | Physical sciences | Concepts: General | Chemistry |
A protocarnivorous plant (sometimes also paracarnivorous, subcarnivorous, or borderline carnivore), according to some definitions, traps and kills insects or other animals but lacks the ability to either directly digest or absorb nutrients from its prey like a carnivorous plant. The morphological adaptations such as st... | Protocarnivorous plant | Wikipedia | 277 | 9270823 | https://en.wikipedia.org/wiki/Protocarnivorous%20plant | Biology and health sciences | Botany | Biology |
Historical observations of the carnivorous syndrome in plant species have been restricted to the more obvious examples of carnivory, such as the active trapping mechanisms of Drosera (the sundews) and Dionaea (Venus flytrap), though authors have often noted speculation about other species that may not be so obviously c... | Protocarnivorous plant | Wikipedia | 480 | 9270823 | https://en.wikipedia.org/wiki/Protocarnivorous%20plant | Biology and health sciences | Botany | Biology |
The broader definition differs mainly in including plants that do not produce their own digestive enzymes but rely on internal food webs or microbes to digest prey, such as Darlingtonia and some species of Heliamphora. The original definition of botanical carnivory, set out in Givnish et al. (1984), required a plant to... | Protocarnivorous plant | Wikipedia | 307 | 9270823 | https://en.wikipedia.org/wiki/Protocarnivorous%20plant | Biology and health sciences | Botany | Biology |
It is thought that these plants that have evolved protocarnivorous habits typically reside in habitats where there is a significant nutrient deficiency, but not the severe deficiency in nitrogen and phosphorus seen where true carnivorous plants grow. The function of the protocarnivorous habit, however, need not be dire... | Protocarnivorous plant | Wikipedia | 404 | 9270823 | https://en.wikipedia.org/wiki/Protocarnivorous%20plant | Biology and health sciences | Botany | Biology |
Dr. George Spomer of the University of Idaho has discovered protocarnivorous activity and function in several glandular plant species, including Cerastium arvense, Ipomopsis aggregata, Heuchera cylindrica, Mimulus lewisii, Penstemon attenuata, Penstemon diphyllus, Potentilla glandulosa var. intermedia, Ribes cereum, Ro... | Protocarnivorous plant | Wikipedia | 428 | 9270823 | https://en.wikipedia.org/wiki/Protocarnivorous%20plant | Biology and health sciences | Botany | Biology |
The glandular hairs on the calyx of plants of the genus Plumbago have been proposed as a potential carnivorous adaptation. While these calyxes have long been considered as a seed dispersal mechanism, many researchers have noted the entrapment of numerous ants and other small insects on the species Plumbago auriculata, ... | Protocarnivorous plant | Wikipedia | 487 | 9270823 | https://en.wikipedia.org/wiki/Protocarnivorous%20plant | Biology and health sciences | Botany | Biology |
Various plants of the Martyniaceae family have been considered crude flypaper protocarnivores. Early publications identified the entrapment of numerous insects on the glandular hairs covering the stems and leaves of Martynia annua, Proboscidea louisiana, Proboscidea parviflora, and Ibicella lutea. Early, rudimentary st... | Protocarnivorous plant | Wikipedia | 363 | 9270823 | https://en.wikipedia.org/wiki/Protocarnivorous%20plant | Biology and health sciences | Botany | Biology |
Another pitfall trap form unrelated to the Sarraceniaceae family are the urns of bromeliad leaves that are formed when leaves are tightly packed together in a rosette, collecting water and trapping insects. Unlike Brocchinia reducta, which has been proven to produce at least one digestive enzyme and can therefore be co... | Protocarnivorous plant | Wikipedia | 491 | 9270823 | https://en.wikipedia.org/wiki/Protocarnivorous%20plant | Biology and health sciences | Botany | Biology |
Puya raimondii and Puya chilensis are two large arid bromeliads that have been suspected of being proto-carnivorous plants due to their entrapment of small animals in their spiny leaves. Puya raimondii was noted to have associated with numerous birds, some of which would become ensnared in the spiky foliage and die. It... | Protocarnivorous plant | Wikipedia | 507 | 9270823 | https://en.wikipedia.org/wiki/Protocarnivorous%20plant | Biology and health sciences | Botany | Biology |
The disciplines of ecology and evolutionary biology have presented several hypotheses on the evolution of carnivorous plants that may also apply to protocarnivorous plants. The name "protocarnivorous plant" itself suggests that these species are on their way to carnivory, though others may simply be an example of a def... | Protocarnivorous plant | Wikipedia | 237 | 9270823 | https://en.wikipedia.org/wiki/Protocarnivorous%20plant | Biology and health sciences | Botany | Biology |
Street photography is photography conducted for art or inquiry that features unmediated chance encounters and random incidents within public places. It usually has the aim of capturing images at a decisive or poignant moment by careful framing and timing. Street photography overlaps widely with candid photography, alth... | Street photography | Wikipedia | 385 | 975495 | https://en.wikipedia.org/wiki/Street%20photography | Technology | Photography | null |
In 1838 or 1839 the first photograph of figures in the street was recorded by Louis-Jacques-Mandé Daguerre in one of a pair of daguerreotype views taken from his studio window of the Boulevard du Temple in Paris. The second, made at the height of the day, shows an unpopulated stretch of street, while the other was take... | Street photography | Wikipedia | 474 | 975495 | https://en.wikipedia.org/wiki/Street%20photography | Technology | Photography | null |
Mass-Observation was a social research organisation founded in 1937 which aimed to record everyday life in Britain and to record the reactions of the 'man-in-the-street' to King Edward VIII's abdication in 1936 to marry divorcée Wallis Simpson, and the succession of George VI. Humphrey Spender made photographs on the s... | Street photography | Wikipedia | 495 | 975495 | https://en.wikipedia.org/wiki/Street%20photography | Technology | Photography | null |
America
Walker Evans worked from 1938 to 1941 on a series in the New York City Subway in order to practice a pure 'record method' of photography; candid portraits of people who would unconsciously come 'into range before an impersonal fixed recording machine during a certain time period'. The recording machine was 'a h... | Street photography | Wikipedia | 392 | 975495 | https://en.wikipedia.org/wiki/Street%20photography | Technology | Photography | null |
Robert Frank's 1958 book, The Americans, was significant; raw and often out of focus, Frank's images questioned mainstream photography of the time, "challenged all the formal rules laid down by Henri Cartier-Bresson and Walker Evans" and "flew in the face of the wholesome pictorialism and heartfelt photojournalism of A... | Street photography | Wikipedia | 455 | 975495 | https://en.wikipedia.org/wiki/Street%20photography | Technology | Photography | null |
Individual approaches in the later twentieth and early twenty-first centuries
Inspired by Frank, in the 1960s Garry Winogrand, Lee Friedlander and Joel Meyerowitz began photographing on the streets of New York. Phil Coomes, writing for BBC News in 2013, said "For those of us interested in street photography there are a... | Street photography | Wikipedia | 512 | 975495 | https://en.wikipedia.org/wiki/Street%20photography | Technology | Photography | null |
Legal concerns
The issue of street photographers taking photographs of strangers in public places without their consent (i.e. 'candid photography' by definition) for fine art purposes has been controversial. Photographing people and places in public is legal in most countries protecting freedom of expression and journ... | Street photography | Wikipedia | 495 | 975495 | https://en.wikipedia.org/wiki/Street%20photography | Technology | Photography | null |
Greece
Production, publication and non-commercial sale of street photography is legal in Greece, without the need to have the consent of the shown person or persons. In Greece the right to take photographs and publish them or sell licensing rights over them as fine art or editorial content is protected by the Constitut... | Street photography | Wikipedia | 504 | 975495 | https://en.wikipedia.org/wiki/Street%20photography | Technology | Photography | null |
United Kingdom
The United Kingdom has enacted domestic law in accordance with the Human Rights Act, which limits the publication of certain photographs in the context of the news media. However, as a general rule, the taking of photographs of other people, including children, in a public place is legal, whether or not ... | Street photography | Wikipedia | 396 | 975495 | https://en.wikipedia.org/wiki/Street%20photography | Technology | Photography | null |
Privacy
An invasion of privacy occurs when an individual's right to privacy is infringed upon by unwelcome intrusion into their private life, including public disclosure of private information. While a person may lose their reasonable expectation of privacy when going out in public according to court precedent, some f... | Street photography | Wikipedia | 217 | 975495 | https://en.wikipedia.org/wiki/Street%20photography | Technology | Photography | null |
In geology, a dike or dyke is a sheet of rock that is formed in a fracture of a pre-existing rock body. Dikes can be either magmatic or sedimentary in origin. Magmatic dikes form when magma flows into a crack then solidifies as a sheet intrusion, either cutting across layers of rock or through a contiguous mass of rock... | Dike (geology) | Wikipedia | 426 | 975686 | https://en.wikipedia.org/wiki/Dike%20%28geology%29 | Physical sciences | Geologic features | Earth science |
It is common for a set of dikes, each a few kilometers long, to form en echelon. This pattern is seen in the Higganum dike set of New England. This dike set consists of individual dikes that are typically four kilometers in length at the surface and up to 60 meters wide. These short segments form longer groups extendin... | Dike (geology) | Wikipedia | 489 | 975686 | https://en.wikipedia.org/wiki/Dike%20%28geology%29 | Physical sciences | Geologic features | Earth science |
Formation
Mafic magma (fluid magma low in silica) usually reaches the surface through fissures, forming dikes.
At the shallowest depths, dikes form when magma rises into an existing fissure. In the young, shallow dikes of the Hawaiian Islands, there is no indication of forceful intrusion of magma. For example, there i... | Dike (geology) | Wikipedia | 508 | 975686 | https://en.wikipedia.org/wiki/Dike%20%28geology%29 | Physical sciences | Geologic features | Earth science |
There is an approximate relationship between the width of a dike and its maximum extent, expressed by the formula:
Here is the thickness of the dike; is its lateral extent; is the excess pressure in the magma relative to the host rock; is the density of the host rock; and is the P-wave velocity of the host rock (... | Dike (geology) | Wikipedia | 452 | 975686 | https://en.wikipedia.org/wiki/Dike%20%28geology%29 | Physical sciences | Geologic features | Earth science |
There may be more than one injection of magma along a given fissure. When multiple injections are all of similar composition, the dike is described as a multiple dike. However, subsequent injections are sometimes quite different in composition, and then the dike is described as a composite dike. The range of compositio... | Dike (geology) | Wikipedia | 351 | 975686 | https://en.wikipedia.org/wiki/Dike%20%28geology%29 | Physical sciences | Geologic features | Earth science |
Dike swarms (also called dike complexes) are exposed in the eroded rift zones of Hawaiian volcanoes. As with most other magmatic dikes, these were fissures through which lava reached the surface. The swarms are typically 2.5 to 5 km in width, with individual dikes about a meter in width. The dike swarms extend radially... | Dike (geology) | Wikipedia | 409 | 975686 | https://en.wikipedia.org/wiki/Dike%20%28geology%29 | Physical sciences | Geologic features | Earth science |
Ring dikes and cone sheets are special types of dikes associated with caldera volcanism. These are distributed around a shallow magma chamber. Cone sheets form when magma is injected into a shallow magma chamber, which lifts and fractures the rock beds above it. The fractures take the form of a set of concentric cones ... | Dike (geology) | Wikipedia | 377 | 975686 | https://en.wikipedia.org/wiki/Dike%20%28geology%29 | Physical sciences | Geologic features | Earth science |
The fire-bellied toads are a group of six species of small frogs (most species typically no longer than ) belonging to the genus Bombina.
The name "fire-bellied" is derived from the brightly colored red- or yellow-and-black patterns on the toads' ventral regions, which act as aposematic coloration, a warning to predat... | Fire-bellied toad | Wikipedia | 505 | 976931 | https://en.wikipedia.org/wiki/Fire-bellied%20toad | Biology and health sciences | Frogs and toads | Animals |
Captivity
Several species in the genus Bombina, particularly B. orientalis, B bombina, and B. variegata, are commonly kept as exotic pets and are readily available in pet stores. In captivity, they are easily maintained in vivaria, and when provided with proper food and environmental conditions, often prove to be robu... | Fire-bellied toad | Wikipedia | 365 | 976931 | https://en.wikipedia.org/wiki/Fire-bellied%20toad | Biology and health sciences | Frogs and toads | Animals |
Halocarbon compounds are chemical compounds in which one or more carbon atoms are linked by covalent bonds with one or more halogen atoms (fluorine, chlorine, bromine or iodine – ) resulting in the formation of organofluorine compounds, organochlorine compounds, organobromine compounds, and organoiodine compounds. Chlo... | Halocarbon | Wikipedia | 481 | 977193 | https://en.wikipedia.org/wiki/Halocarbon | Physical sciences | Halocarbons | Chemistry |
Natural halocarbons
A large amount of the naturally occurring halocarbons, such as dioxine, are created by wood fire and volcanic activity. A third major source is marine algae, which produce several chlorinated methane and ethane containing compounds. Several thousand complex halocarbons are known to be produced main... | Halocarbon | Wikipedia | 486 | 977193 | https://en.wikipedia.org/wiki/Halocarbon | Physical sciences | Halocarbons | Chemistry |
Common uses for halocarbons have been as solvents, pesticides, refrigerants, fire-resistant oils, ingredients of elastomers, adhesives and sealants, electrically insulating coatings, plasticizers, and plastics. Many halocarbons have specialized uses in industry. One halocarbon, sucralose, is a sweetener.
Before they b... | Halocarbon | Wikipedia | 359 | 977193 | https://en.wikipedia.org/wiki/Halocarbon | Physical sciences | Halocarbons | Chemistry |
Haloaromatics include the former Aroclors (Monsanto Company trademark for polychlorinated biphenyls, PCBs), once widely used in power transformers and capacitors and in building caulk, the former Halowaxes (Union Carbide trademark for polychlorinated naphthalenes, PCNs), once used for electrical insulation, and the chl... | Halocarbon | Wikipedia | 443 | 977193 | https://en.wikipedia.org/wiki/Halocarbon | Physical sciences | Halocarbons | Chemistry |
In 1962 a book by U.S. biologist Rachel Carson started a storm of concerns about environmental pollution, first focused on DDT and other pesticides, some of them also halocarbons. These concerns were amplified when in 1966 Danish chemist Soren Jensen reported widespread residues of PCBs among Arctic and sub-Arctic fis... | Halocarbon | Wikipedia | 401 | 977193 | https://en.wikipedia.org/wiki/Halocarbon | Physical sciences | Halocarbons | Chemistry |
In organic chemistry, a substituent is one or a group of atoms that replaces (one or more) atoms, thereby becoming a moiety in the resultant (new) molecule. (In organic chemistry and biochemistry, the terms substituent and functional group, as well as side chain and pendant group, are used almost interchangeably to des... | Substituent | Wikipedia | 512 | 977244 | https://en.wikipedia.org/wiki/Substituent | Physical sciences | Concepts_2 | Chemistry |
The use of the suffix is determined by the number of hydrogen atoms that the substituent replaces on a parent compound (and also, usually, on the substituent). According to the 1993 IUPAC recommendations:
-yl means that one hydrogen is replaced.
-ylidene means that two hydrogens are replaced by a double bond betwee... | Substituent | Wikipedia | 288 | 977244 | https://en.wikipedia.org/wiki/Substituent | Physical sciences | Concepts_2 | Chemistry |
For many common compounds the substituent is linked at one end (the 1 position) and historically not numbered in the name. The IUPAC 2013 Rules however do require an explicit locant for most substituents in a preferred IUPAC name. The substituent name is modified by stripping -ane (see alkane) and adding the appropriat... | Substituent | Wikipedia | 484 | 977244 | https://en.wikipedia.org/wiki/Substituent | Physical sciences | Concepts_2 | Chemistry |
Statistical distribution
One cheminformatics study identified 849,574 unique substituents up to 12 non-hydrogen atoms large and containing only carbon, hydrogen, nitrogen, oxygen, sulfur, phosphorus, selenium, and the halogens in a set of 3,043,941 molecules. Fifty substituents can be considered common as they are fou... | Substituent | Wikipedia | 219 | 977244 | https://en.wikipedia.org/wiki/Substituent | Physical sciences | Concepts_2 | Chemistry |
The Santiago Metro () is a rapid transit system serving the city of Santiago, the capital of Chile. It currently consists of seven lines (numbered 1-6 and 4A), 143 stations, and of revenue route. The system is managed by the state-owned Metro S.A. and is the first rapid transit system in the country.
The Santiago Met... | Santiago Metro | Wikipedia | 473 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
On 15 September 1975, the first line of the metro was opened by Augusto Pinochet during the military dictatorship. Line 1, during its opening stage, was mostly underground from San Pablo to La Moneda, running below the Alameda. In 1977, the line was extended towards Providencia and by 1980, the line reached as far as E... | Santiago Metro | Wikipedia | 479 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
Following the economic recovery after the second miracle, the metro's expansion plans resurged. Population growth in the southeastern area of the capital became unstoppable during the 1980s, and La Florida became the most populous commune in the country, thus the construction of a new line to supply that area was param... | Santiago Metro | Wikipedia | 417 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
These new projects were designed to make Metro the key element of the new transport reform plan for the city, Transantiago. Along with the new extensions, exchange stations were designed to allow for a better interaction between the urban railways and other means of transport, mainly buses. The first exchange station w... | Santiago Metro | Wikipedia | 512 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
Along with the extension to Las Condes, one of the most important projects of the service was announced: the extension of the metro to the west, connecting the communes of Maipú, Pudahuel, Lo Prado and Quinta Normal to the Metro Network. In this way, the Metro approached the western sector of the city for the first tim... | Santiago Metro | Wikipedia | 461 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
On November 2, 2017, Line 6 was inaugurated from Cerrillos to Los Leones adding 10 new stations. This new line does not have staffed ticket offices; instead there are automatic machines for ticket sales and loading money onto bip! cards. It has platform-edge doors to protect passengers, and traction power is supplied b... | Santiago Metro | Wikipedia | 493 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
The Metro network had been partially reactivated as of Monday, October 21; however, due to the damage of some stations, the network will only be available in its entirety within a period of up to 7 months. Damage costs are estimated at more than $300 million. Metro de Santiago indicated that it does not have insurance ... | Santiago Metro | Wikipedia | 466 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
One year after the announcement of Line 7, President Sebastián Piñera announced in his 2018 annual account that studies would begin for the construction of two new metro lines in a north–south direction: Line 8, which will connect the communes of La Florida and Puente Alto with Providencia, while Line 9 would reach fro... | Santiago Metro | Wikipedia | 428 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
During the inauguration of Line 3 in 2019, President Sebastián Piñera declared that Line 10 was going to be built. Although Metro indicated that a tenth line was not officially in its project portfolio, the government indicated that the initiative attempted to connect the Avenida Mapocho sector with Avenida Tobalaba, f... | Santiago Metro | Wikipedia | 423 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
On November 2, 2017, the line 6 entered revenue service. This line utilizes the AS-2014 (Acero Santiago 2014) which are the most modern stock of the system , being the first model in the system that are driverless. However, in the first and last car there is a control panel meant to control the train when necessary. It... | Santiago Metro | Wikipedia | 504 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
Customers may rent a parking space for their bicycles through the Bicimetro network, which opened in 2008 at six stations and is slowly expanding, for a starting cost of $300 (approximately US$0.50) a day. There are weekly and monthly rental services too, that guarantee a fixed space for the bike (contrary to the daily... | Santiago Metro | Wikipedia | 385 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
Pricing and working hours
Metro is part of Red Metropolitana de Movilidad, the integrated public transport system that serves the capital using also feeder and main bus routes. Red works with an integrated fare system, which allows passengers to make bus-bus or bus-metro transfers on a two-hour time limit from the fir... | Santiago Metro | Wikipedia | 490 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
On weekdays, the metro operates from 5.35 am until 12.08 am, while on Saturdays it operates from 6.30 am until 12.08 am and on Sundays and public holidays the metro operates from 8 am (Line 1 from 9 am) until 11.48 pm. However, due to the COVID-19 Pandemic, operating hours have varied in accordance with national curfew... | Santiago Metro | Wikipedia | 92 | 977418 | https://en.wikipedia.org/wiki/Santiago%20Metro | Technology | Americas | null |
The rings of Saturn are the most extensive and complex ring system of any planet in the Solar System. They consist of countless small particles, ranging in size from micrometers to meters, that orbit around Saturn. The ring particles are made almost entirely of water ice, with a trace component of rocky material. There... | Rings of Saturn | Wikipedia | 455 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
Galileo Galilei was the first to observe the rings of Saturn in 1610 using his telescope, but was unable to identify them as such. He wrote to the Duke of Tuscany that "The planet Saturn is not alone, but is composed of three, which almost touch one another and never move nor change with respect to one another. They ar... | Rings of Saturn | Wikipedia | 431 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
Huygens began grinding lenses with his father Constantijn in 1655 and was able to observe Saturn with greater detail using a 43× power refracting telescope that he designed himself. He was the first to suggest that Saturn was surrounded by a ring detached from the planet, and famously published the letter string "". Th... | Rings of Saturn | Wikipedia | 373 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
Four robotic spacecraft have observed Saturn's rings from the vicinity of the planet. Pioneer 11s closest approach to Saturn occurred in September 1979 at a distance of . Pioneer 11 was responsible for the discovery of the F ring. Voyager 1s closest approach occurred in November 1980 at a distance of . A failed photopo... | Rings of Saturn | Wikipedia | 413 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
Saturn's axial inclination
Saturn's axial tilt is 26.7°, meaning that widely varying views of the rings, of which the visible ones occupy its equatorial plane, are obtained from Earth at different times. Earth makes passes through the ring plane every 13 to 15 years, about every half Saturn year, and there are about e... | Rings of Saturn | Wikipedia | 437 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
Cassini directly measured the mass of the ring system via their gravitational effect during its final set of orbits that passed between the rings and the cloud tops, yielding a value of 1.54 (± 0.49) × 1019 kg, or 0.41 ± 0.13 Mimas masses. This is around two-thirds the mass of the Earth's entire Antarctic ice sheet, sp... | Rings of Saturn | Wikipedia | 186 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
Although the largest gaps in the rings, such as the Cassini Division and Encke Gap, can be seen from Earth, the Voyager spacecraft discovered that the rings have an intricate structure of thousands of thin gaps and ringlets. This structure is thought to arise, in several different ways, from the gravitational pull of S... | Rings of Saturn | Wikipedia | 464 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
In 1980, Voyager 1 made a fly-by of Saturn that showed the F ring to be composed of three narrow rings that appeared to be braided in a complex structure; it is now known that the outer two rings consist of knobs, kinks and lumps that give the illusion of braiding, with the less bright third ring lying inside them.
Ne... | Rings of Saturn | Wikipedia | 347 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
There are two main hypotheses regarding the origin of Saturn's inner rings. A hypothesis originally proposed by Édouard Roche in the 19th century is that the rings were once a moon of Saturn (named Veritas, after a Roman goddess who hid in a well). According to the hypothesis, the moon's orbit decayed until it was clos... | Rings of Saturn | Wikipedia | 463 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
The idea of massive early rings was subsequently extended to explain the formation of Saturn's moons out to Rhea. If the initial massive rings contained chunks of rocky material (>100 km; 60 miles across) as well as ice, these silicate bodies would have accreted more ice and been expelled from the rings, due to gravita... | Rings of Saturn | Wikipedia | 498 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
Research based on rates of infall into Saturn favors a younger ring system age of hundreds of millions of years. Ring material is continually spiraling down into Saturn; the faster this infall, the shorter the lifetime of the ring system. One mechanism involves gravity pulling electrically charged water ice grains down... | Rings of Saturn | Wikipedia | 500 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
Present in the D Ring is a finescale structure with waves 30 km (20 miles) apart. First seen in the gap between the C Ring and D73, the structure was found during Saturn's 2009 equinox to extend a radial distance of 19,000 km (12,000 miles) from the D Ring to the inner edge of the B Ring. The waves are interpreted as a... | Rings of Saturn | Wikipedia | 512 | 977592 | https://en.wikipedia.org/wiki/Rings%20of%20Saturn | Physical sciences | Solar System | Astronomy |
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