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56,319,023 | https://en.wikipedia.org/wiki/8%20Draconis | 8 Draconis, formally named Taiyi , is a single star in the northern circumpolar constellation of Draco. Based upon an annual parallax shift of 34.14 mas as seen from the Earth, the star is located approximately 96 light-years from the Sun. It is moving further away with a heliocentric radial velocity of +9 km/s, having come within some 2.6 million years ago.
This is an F-type main-sequence star with a stellar classification of F1VmA7(n). It is a Gamma Doradus variable star with a brightness variation of about one tenth of a magnitude. 8 Dra has a relatively high rate of rotation, showing a projected rotational velocity of 120 km/s. The star has 1.56 times the mass of the Sun and 1.50 times the Sun's radius. It is radiating 5.75 times the Sun's luminosity from its photosphere at an effective temperature of 7,129 K. An infrared excess has been detected at wavelengths of 24 and 70μm, which suggests the presence of a circumstellar disk orbiting the star.
Nomenclature
8 Draconis is the star's Flamsteed designation. It also received the variable star designation IR Draconis in 2000, after its variability had been discovered using Hipparcos photometry.
The star bore the traditional Chinese name of Taiyi, from 太乙 (Tài Yǐ) or 太一 (Tài Yī, the Great One), both of which refer to Tao. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN approved the name Taiyi for this star on 30 June 2017 and it is now so entered on the List of IAU-approved Star Names.
References
F-type main-sequence stars
Gamma Doradus variables
Circumstellar disks
Draco (constellation)
Draconis, 08
112429
063076
4916
Draconis, IR
Taiyi | 8 Draconis | [
"Astronomy"
] | 424 | [
"Constellations",
"Draco (constellation)"
] |
56,319,398 | https://en.wikipedia.org/wiki/HD%20121228 | HD 121228 is a blue supergiant star located in the constellation Centaurus. The star is noted for its close visual proximity to the planetary nebula SuWt 2.
References
See also
Zeta Persei - Same spectral class
121228
068034
B-type supergiants
Centaurus
Durchmusterung objects | HD 121228 | [
"Astronomy"
] | 67 | [
"Centaurus",
"Constellations"
] |
56,320,236 | https://en.wikipedia.org/wiki/Pointing | Pointing is a gesture specifying a direction from a person's body, usually indicating a location, person, event, thing or idea. It typically is formed by extending the arm, hand, and index finger, although it may be functionally similar to other hand gestures. Types of pointing may be subdivided according to the intention of the person, as well as by the linguistic function it serves.
Pointing typically develops within the first two years of life in humans, and plays an important role in language development and reading in children. It is central to the use of sign language, with a large number of signs being some variation on pointing. The nature of pointing may differ for children who have autism or who are deaf, and may also vary by gender. It is typically not observed in children who are blind from birth.
Pointing may vary substantially across cultures, with some having many distinct types of pointing, both with regard to the physical gestures employed and their interpretation. Pointing, especially at other people, may be considered inappropriate or rude in certain contexts and in many cultures. It is generally regarded as a species-specific human feature that does not normally occur in other primates in the wild. It has been observed in animals in captivity; however, there is disagreement on the nature of this non-human pointing.
Definition and types
The primary purpose of pointing is to indicate a direction, location, event or thing relative to a person. Pointing is typically defined as having either three or four essential elements:
Extension of the index finger;
Flexing the remaining fingers into the palm, possibly with the thumb to the side;
Usually, but not always, the pronation of the palm to face downward, or to face the mid-line of the body; and
Extension of the arm.
Gestures that do not meet these three or four criteria are usually classified as a "reach" or an “indicative gesture”, although there is no clear consensus on how to differentiate between the two. Additionally, there may be little or no behavioral or functional difference depending on whether a gesture is considered to be pointing, reaching, or otherwise indicative, and reaching may be considered a form of whole-hand pointing. In one review, 11 separate definitions were identified for the related motions of reach, reaching out, reaching, indicating, and indicates.
Imperative, declarative and interrogative pointing
Types of pointing are traditionally further divided by purpose, between imperative and declarative pointing. Imperative pointing is pointing to make a request for an object, while declarative pointing is pointing to declare, to comment on an object. As Kovacs and colleagues phrase it, "'Give that to me' vs. 'I like that'". This division is similar to that made by Harris and Butterworth between "giving" and "communicative" pointing. Determining the intention of pointing in infants is done by considering three factors:
Whether the behavior is direct toward another,
Whether it includes "visual-orientation behaviors" such as observing the recipient of the pointing in addition to the object pointed to, and
Whether the gesture is repeated if it fails to achieve the intended effect on the recipient.
Declarative pointing may further be divided into declarative expressive pointing, to express feelings about a thing, and declarative interrogative pointing, to seek information about a thing. However, according to Kovacs and colleagues interrogative pointing is clearly different from declarative pointing, since its function is to gain new information about a referent to learn from a knowledgeable addressee. Therefore, unlike declarative pointing, interrogative pointing implies an asymmetric epistemic relation between communicative partners.
Linguistic function
Types of communicative pointing may be divided by linguistic function into three main groups:
Objective pointing: pointing to an object within the visual field of both the pointer and the receiver, such as pointing to a chair which is physically present
Syntactic or anaphoric pointing: pointing to linguistic entities or expressions previously identified, such as pointing to the chair which is not physically present
Imaginative pointing: pointing to things that exist in the imagination, such as pointing to a fictional or remembered chair
Additionally, pointing in children who are deaf may be divided between diectic or "natural" pointing, which is shared with hearing children, and symbolic pointing used specifically in sign language, learned by observing and imitating others who sign.
Development
Pointing is the first communicative gesture that develops in human infants. It is not clear to what extent the behavior may first emerge as a form of meaningless ritualization, whether some infants may comprehend and visually follow the pointing of others without yet pointing themselves, or whether pointing begins as a form of meaningful imitation, where an infant learns they can produce the same effect in adults as adult produce in them, by mimicking the action of pointing, and drawing attention to an object.
Pointing generally emerges within the first two years of life, weeks prior to a baby's first spoken word, and plays a central role in language acquisition. The onset of pointing behavior is typically between seven and 15 months of age, with an average of between 11 months and one year. By eight months, parents reported that 33% of babies exhibited pointing behaviors, with pointing to nearby objects usually occurring by 11 months, and pointing to more distant object by 13 months. By one year of age, more than half of children will exhibit pointing behavior.
As early as 10 months of age, children have been shown to spend more time being attentive to novel objects when they are pointed to by others, when compared to objects that are merely presented to them. This time is increased if the object is also labelled verbally. Pointing by children is associated with a high rate of verbal response from adults, specifically labeling the object pointed to. This interaction allows the child to check for words labeling objects they do not yet know, and, when combined with declarative verbal statements on the part of the child, may allow them verify the accuracy of words they have already learned.
Infants may begin to point in situations where no one else is present, as a form of egocentric expression, termed "pointing-for-self". This is differentiated from "pointing-for-others" which is done while looking at a "recipient" of the pointing, and done as a communicative gesture. Kita specifies this variety of pointing in the context of being a deictic gesture, which is done for the benefit of an audience, as distinct from what are deemed "superficially similar behaviors". Demonstrating this, as they mature infants will first point at an object, and then visually verify whether the recipient is being attentive to the object, and by 15 months of age, will first verify that they have the attention of the recipient, and only then point as a means of redirecting that attention.
Children are more likely to point for adults who respond positively to the gesture. At 16 months they are less likely to point for adults who are shown to be unreliable, adults who have mislabeled objects the children already know the correct word for. At two years of age, children have been shown to be more likely to point for adults than for children their own age.
Relationship with language
A meta-analysis by Colonnesi and colleagues found a strong relationship between pointing and language, including between pointing at an early age and language ability in later life, and pointing at an early age as a predictor of two-word vocal combinations. They concluded that only a "few studies" had not found a strong correlation between pointing and the development of language. Research has also shown that the frequency of communicative pointing from ages 9 months to 12.5 months was positively correlated with vocabulary size for children at age two. The relationship between language development and pointing tends to be stronger in studies which examined declarative pointing specifically or pointing generally, rather than imperative pointing.
In school age children, finger-pointing-reading (reading while pointing to words or letters as they are spoken) can play an important role in reading development, by helping to emphasize the association between the spoken and printed word, and encouraging children to be attentive to the meaning of text.
Deaf speakers of sign language
Pointing plays an important role in sign language, which as much as 25% of signs being a variation of pointing. Children who are deaf have been shown to begin pointing at a similar age to non-deaf children, but this did not confer any advantage in the acquisition of pronouns in American Sign Language.
Initial observations give some indication that deaf children acquiring the use of American Sign Language (ASL) may exhibit self-pointing behavior earlier than hearing children who are acquiring speech. Pointing to a location begins being deictic for deaf children and hearing alike, but becomes lexicalized for more mature signers. There is a distinction between linguistic pointing in ASL and gestural pointing by deaf users, the latter being identical for deaf and hearing people.
One small-scale study found that the errors in pointing behavior produced by autistic deaf children and autistic hearing children were similar. Both deaf and hearing children use pointing abundantly while learning language, and initially for the same reason, although that starts to diverge as deaf children acquire signs. Pre-verbal hearing infants use pointing extensively, and use a combination of one word plus one gesture (mostly pointing) before they can produce a two-word sentence. Another study looked at deaf Japanese infants acquiring language from ages four months to two years, and found that the infants moved from duos (where a point plus an iconic sign referred to the same thing) to two-sign combinations where they referred to two different things. As they grew, the latter grew more frequent and led to the development of two-sign sentences in Japanese Sign Language.
Autistic people
Children with autism show marked differences compared to others, and greater difficulty in their ability to interpret pointing as a form of communication, and a sign of "something interesting". This is similar to difficulties they may experience with other deictic communication, which depend on an interpretation of the relationship between speaker and listener or on particular spatial references. A lack of declarative or proto-declarative pointing and the inability to follow a point are important diagnostic criteria for children with autism, and have been incorporated into screening tools such as the Modified Checklist for Autism in Toddlers.
Other factors
Pointing is dependent on vision, and is not observed in children who are blind from birth. A number of differences have been observed regarding the onset of pointing behavior and gender, and the tendency to point using the right or left hand, with girls being more likely to point up to 15 degrees into the left visual periphery using their right hand, and being ambidextrous further to the left, while boys are typically ambidextrous for 15 degrees to the left and right of center.
Pointing at remembered targets can be impaired in cognitive impairment due to dementia.
Cultural variations
The gestures used for pointing and their interpretation vary among different cultures. While studies have observed index finger pointing in infants across a range of cultures, because those studied are also ones where adults frequently use this type of pointing, further study is needed to determine whether these are examples of imitation of behaviors performed by observed adults, or whether it indicates pointing may be biologically determined.
In much of the world, pointing with the index finger is considered rude or disrespectful, especially pointing to a person. Pointing with the left hand is taboo in some cultures. Pointing with an open hand is considered more polite or respectful in some contexts. In Nicaragua, pointing is frequently done with the lips in a "kiss shape" directed towards the object of attention.
Different cultures may point using a range of variations on index finger pointing. In Japan, pointing is done with the fingers together and the palm facing upwards. Those of Indian heritage may point using the chin, whole hand, or thumb. They may consider index finger pointing rude, but further distinguish a point using two fingers for use only at someone considered inferior. In those living near the Vaupés River, Dixon noted at least three distinct types of pointing:
pointing with the lips for "visible and near" ... pointing with the lips plus a backwards tilt of the head for "visible and not near" ... pointing with the index finger for "not visible" (if the direction in which the object lies is known)
Alternatively, among Aboriginal Australian speakers of Arrernte, researchers identified six distinct types of pointing: index finger, open hand palm down, open hand palm vertical, "'horn-hand' pointing (with the thumb, the index finger and the pinkie extended)", pointing with a protruded lip, and pointing with the eye.
When pointing to indicate a position in time, many, but not all cultures tend to point toward the front to indicate events in the future, and toward the back to indicate events in the past. One noted exception is that of speakers of Aymara, who instead tend to associate what is in the past, what is known, with what is in the front, what is seen, and vice versa.
In non-human animals
There is considerable disagreement as to the nature of pointing behaviors in non-human animals. Miklósi and Soproni described pointing as a "species specific, human communicative gesture" not regularly used by any other species of primates living in the wild. Kita concluded similarly that "on the evidence to date only humans use the pointing gesture declarative to share attention with conspecifics." Kovács and colleagues state "pointing as a referential communicative act seems to be unique to human behavior."
However, the claims that pointing is a unique human gesture have not gone unchallenged. A study in 1998 by Veà and Sabater-Pi described examples of explicit declarative pointing in bonobos in what is now the Democratic Republic of the Congo through these observations: “Noises are heard coming from the vegetation. A young male swings from a branch and leaps into a tree... He emits sharp calls, which are answered by other individuals who are not visible. He points—with his right arm stretched out and his hand half closed except for his index and ring fingers—to the position of the two groups of camouflaged observers who are in the undergrowth.” This was one of the only observations of pointing in the wild by primates for years, but recently other possible examples have been documented. Researchers claimed to observe imperative pointing gestures produced by bonobos when attempting to initiate genital rubbing, as well as by chimpanzees when reaching towards objects they desired, although even these researchers admitted the rarity of chimpanzee pointing in the wild. In the wild, both chimpanzees and bonobos have been shown to seemingly signal and gesture to direct each other's attention, through acts like beckoning and “directed scratching.” Thus, while it is clear that other primates use gestures to direct attention, it is still uncertain as to whether this is done overtly as in humans through pointing.
Although the question of whether primates point in the wild is still up for debate, pointing in captivity is widely established in primates. Leavens and Hopkins note that pointing behavior has been observed in captivity for a range of species. In some, such as apes, the majority of such behavior is spontaneous (meaning without explicit training to do so), but occurs only rarely in others, such as monkeys. When present, this may be accompanied by visual monitoring of the person being interacted with, the audience of their gesture, rather than being attentive only to the object pointed at. Moreover, it seems that non-human great apes also take the perspective of the communicative partner in order to produce clear, unambiguous points. Studies have found that apes point with the dual goal of directing attention and requesting food, and additionally that they are sensitive to the looking behavior in response to their pointing gestures. There remain questions as to whether this constitutes "true pointing", and whether non-humans have the social or cognitive abilities to understand the intentional communicative nature of pointing. These questions arise especially due to the nature of these primate pointing gestures. They are only produced for humans and not for other apes, and often use the full hand instead of the typical extended index finger that humans use. However, this may be countered with observations in apes trained to use sign language, which do point with the index finger. Recently, studies have also indicated that chimpanzees in captivity use pointing as a flexible signal, by raising their arms in order to point to objects that are further away. Thus, while apes certainly can point, it is difficult to ascertain whether they point naturally. However, this debate may result from the fact that there are procedural differences in how non-human primates are tested, making it more difficult to ascertain if non-human primates do point. The experimenter must be safe, as a result of testing non-human primates, thus a barrier is introduced between the participant and experimenter. Dogs and infants do not have this precaution. However, Udell and colleagues tested dogs with and without a fence, using the object choice task in a similar manner to that of a barrier. The authors reported that the barrier produced a decrease of 31% in terms of success for canines. This has also been shown in pointing as well, where barriers that are present for dogs showed lower success rates than when absent, highlighting that this debate may be partially the result of systematic procedural differences.
In contrast to the production of pointing, some non-human animal species can appropriately respond to pointing gestures, preferring an object or direction, which was previously indicated by the gesture. Cats, elephants, ferrets, horses and seals can follow the pointing gesture of a human above chance, while dogs can rely on different types of human points and their performance is comparable to that of 2-year-old toddlers in a similar task. However, it seems, that the default function of pointing is different in dogs and humans, because pointing actions refer to particular locations or directions for dogs in an imperative manner, while these gestures usually indicate specific objects in humans to ask for new information or to comment on an object.
There is considerable debate as to whether apes are able to comprehend pointing gestures as well, and it has even been argued that dogs are better able to understand pointing than apes. Some hypothesize that pointing comprehension should be more prevalent in species with a stronger tendency to cooperate, which would explain negative results in apes due to the mainly competitive relationship present in most species of apes and monkeys. However, wolves fare poorly in pointing comprehension tests as well, and are a highly cooperative species, countering this hypothesis. More recent studies have refuted the claim that apes are poor at comprehending pointing, and provide evidence that the tests used to evaluate pointing comprehension are often inaccurate, especially in apes. Thus there is conflicting evidence and debate as to whether apes fully comprehend pointing gestures.
See also
Deixis, words and phrases that cannot be fully understood without additional contextual information
Finger gun, a similar hand gesture
Joint attention, shared focus of two people on an object, resulting from pointing or other cues
List of gestures used in non-verbal communication
Ostensive definition, conveys the meaning of a term by pointing out examples
Pointing breed, dogs trained to find and indicate the direction of game
Pointing device, an input interface for inputting spatial data into a computer
Semiotics, the study of meaning-making, sign process, and meaningful communication
Sign (semiotics), something that communicates a meaning that is not the sign itself
Notes
References
External links
Hand gestures
Developmental psychology
Nonverbal communication | Pointing | [
"Biology"
] | 4,019 | [
"Behavioural sciences",
"Behavior",
"Developmental psychology"
] |
56,321,751 | https://en.wikipedia.org/wiki/Martha%20Austin%20Phelps | Martha Austin Phelps was an American chemist who conducted research in measuring metal concentrations and developed several analytical protocols to do so. She also worked on the early development of ester synthesis. In between conducting research, she worked as school teacher teaching chemistry and physics. She finished her career as an activist in women's academic clubs. Her chemistry career lasted approximately 10 years, resulting in 15 publications, which set her apart as one of the most skilled female chemists within the first generation of women chemists in the United States.
Biography
Martha was born in Georgia, Vermont on February 13, 1870. She grew up in Easthampton, Massachusetts where she graduated high school. She earned her B.S. degree from Smith College in 1892. Prior to enrolling in graduate school at Yale University, she taught as a science teacher in New York and Massachusetts. She started graduate school in 1896 and graduated with her Ph.D. in chemistry in 1898. After completing her Ph.D., she continued working for her Ph.D. advisor, Andrew Gooch in the Kent Chemistry Laboratory for one year and then transferred to the Rhode Island Experiment Station where she worked as an assistant chemist in 1900. From 1901-1904, she went back to being a science teacher and taught chemistry and physics at Wilson College. In 1904, she also married Issac King Phelps, who was working as a chemistry instructor at Yale and George Washington University at the time. In 1908, the couple moved to Washington D.C. where Martha went to work for the Bureau of Standards as a chemistry researcher and Issac went to work for the U.S. Department of Agriculture. Martha ceased working as researcher in 1909. Martha was one of the first female scientists to be employed by the Bureau of Standards. After 1909, she began her activist work in women's education clubs until retirement. Martha and Issac lived in Washington D.C until 1923, until they moved to New Haven, Connecticut where Martha eventually died on March 15, 1933.
Work in Science
Martha spent much of her scientific career interested in the quantitative analysis of various elements. Specifically, she studied the composition of ammonium phosphates in magnesium, zinc, and cadmium. Her study of ammonium phosphates was later used as a tool in her later analytical work. Martha spent much of her research career developing several analytical procedures for metal estimations and separations, with a special focus on gravimetric estimations of manganese and magnesium. Her other work included the analysis of prehistoric bronzes without major disruption to the metal composition and the study of organic esters.
While in graduate school at Yale, she worked for Andrew Gooch in the Kent Chemical Laboratory. Throughout her time in graduate school, she published nine papers in the American Journal of Science and in Zeitschrift für anorganische und allgemeine Chemie for her work in analytical chemistry. Four of the nine papers she published individually and the other five in collaboration with Gooch. After her marriage to Issac King Phelps in 1904, she collaborated with her husband to study ester synthesis. The work resulted in six more publications. In total, she published fifteen papers throughout the span of her ten year career as a chemist.
Martha's work is primarily recognized for her development of a protocol estimating arsenic as ammonium magnesium arsenate. The paper detailing the procedure was published in 1900. The protocol became a standard method of arsenic estimation in quantitative analysis studies and was written into textbooks for several years.
Awards
From 1897-1898, she was granted a graduate scholarship to pursue her PhD. Upon completion of her PhD, she was granted one of Yale's University Fellowships to continue work in Gooch's laboratory until 1899.
References
People from Easthampton, Massachusetts
People from Georgia, Vermont
Smith College alumni
Yale University alumni
Wilson College (Pennsylvania) faculty
Scientists from New Haven, Connecticut
Sportspeople from Washington, D.C.
1870 births
1933 deaths
Analytical chemists
American chemists
Chemists from Vermont | Martha Austin Phelps | [
"Chemistry"
] | 804 | [
"Analytical chemists"
] |
56,322,565 | https://en.wikipedia.org/wiki/Kazan%20Soda%20Elektrik | The Kazan Soda Elektrik, full name Kazan Soda Elektrik Üretim A.Ş., is a chemical industry and electric energy company in Ankara Province, Turkey producing natural soda ash and baking soda from trona. The company is a subsidiary of Ciner Holding.
Background
The trona ore deposits were owned by Rio Tinto Group, an Australian-British multinational and one of the world's largest metals and mining corporation. After survey activities, which lasted more than fifteen years, the company concluded that it will be unable to operate the mining of the trona ore reserves there, and sold the deposits to Ciner Holding in 2010.
The construction of the soda products plant began in 2015, after five years of efforts for bureaucratic permissions and financing. The investment budget of the project was US$1.5 billion. The financing of the project was provided by the Industrial and Commercial Bank of China (ICBC), Exim Bank of China and Deutsche Bank backed by the China Export and Credit Insurance Corporation (Sinosure). Sberbank of Russia financially contributed during the groundbreaking phase. The construction of the facility was carried out by the China Tianchen Engineering Corporation (TCC). The facility was completed within two and half years. Kazan Soda Elektrik plant was inaugurated on January 15, 2018, in presence of Turkish President Recep Tayyip Erdoğan, Minister of Energy and Natural Resources Berat Albayrak, Minister of Labour and Social Security Jülide Sarıeroğlu, Ambassador of China Yu Hongyang and many other high-profile politicians and officials.
Plant and production
The Kazan Soda Elektrik consists of three sections, namely mining, processing and cogeneration. While the mining area is located in Kahramankazan district, the production plant is situated within the Sincan district of Ankara Province, northwest of Ankara. It is about north of Ankara.
The plant's mining section supplies the processing section with the
trona solution (trisodium hydrogendicarbonate dihydrat), which is the primary source of soda ash. For this, trona ore, laying in average at a depth of underground, is injected with hot water through boreholes drilled, and the dissolved trona is pumped up in the form of trona solution. The plant has five processing lines. The congeneration facility produces 380 MWe electric power and 400 tons of steam.
The annual production capacity of the plant is 2.5 million tons of soda ash (sodium carbonate, Na2CO3) and 200,000 tons of baking soda (sodium bicarbonate, NaHCO3). If all the production were exported to Europe, it would increase the key glass raw material by around 25%. Around 1,000 people are employed by the company.
The trona ore reserve of Kazan Soda Elektrik is the world's second largest. The plant is the biggest soda ash production facility in Europe. With both Kazan Soda and Eti Soda, the Ciner Holding and Turkey becomes the leading soda ash producer of the world. The soda ash produced has a purity grade of 99.8%, which is the purest in the world. The total annual export value of the products from Kazan Soda Elektrik and Eti Soda will be US$800 million.
Sustainability
The company has published a report by CDP scoring their environmental impact. Their scope 1 and 2 emissions intensity in 2019 was 0.345 tonnes CO2e per tonne of product. However, the first implementation of the EU Carbon Border Adjustment Mechanism does not include soda.
See also
Eti Soda, Turkey
Ciner Wyoming, United States
References
Ciner Glass and Chemicals Group
Mining companies of Turkey
Chemical companies of Turkey
Chemical plants
Industrial buildings in Turkey
Industrial buildings completed in 2018
Chemical companies established in 2010
Non-renewable resource companies established in 2010
2010 establishments in Turkey
Companies based in Ankara
Kahramankazan District
Sincan, Ankara
21st-century architecture in Turkey | Kazan Soda Elektrik | [
"Chemistry"
] | 808 | [
"Chemical process engineering",
"Chemical plants"
] |
71,967,166 | https://en.wikipedia.org/wiki/Quadrant%20House%20%28Durban%29 | The Quadrant House is a Grade II listed building situated in Durban, South Africa.
History
The building, erected in 1929, was commissioned by H. Live and designed by architect Ritchie McKinlay. It is assumed that its original purpose was to be a naval training school.
Description
The building is located on the Victoria Embankment in Durban's city centre. It occupies a lot with the shape of a quarter circle or quadrant, from which it derives its name. It is considered one of the epitomes of the so-called Berea Style, a local declination of the Art Deco style which emerged from local interest in Spanish colonial architecture as found on the West coast of North America.
See also
List of heritage sites in KwaZulu-Natal
References
External links
Buildings and structures in Durban
Heritage listed buildings and structures by country
Buildings and structures completed in 1929
1929 establishments in South Africa
Art Deco architecture in South Africa | Quadrant House (Durban) | [
"Engineering"
] | 184 | [
"Heritage listed buildings and structures by country",
"Architecture"
] |
71,968,234 | https://en.wikipedia.org/wiki/Journal%20of%20Social%20and%20Evolutionary%20Systems | The Journal of Social and Evolutionary Systems was a quarterly peer-reviewed scientific journal covering the intersection of biology and sociology. It was established in 1978 as the Journal of Social and Biological Structures by James Danielli and Harvey Wheeler, who served as its founding editors-in-chief; they were later joined by Robert Rosen. Wheeler remained a co-editor-in-chief of the journal until 1995.
The journal was originally published by Academic Press until 1990, when it was acquired by JAI Press. Also in 1990, Paul Levinson became the journal's new editor-in-chief. In 1992, Levinson changed its title to the Journal of Social and Evolutionary Systems in 1992. The journal ceased publication in 1998.
References
External links
Academic journals established in 1978
Publications disestablished in 1998
Academic Press academic journals
Evolutionary biology journals
Sociobiology
Quarterly journals
English-language journals | Journal of Social and Evolutionary Systems | [
"Biology"
] | 174 | [
"Behavioural sciences",
"Behavior",
"Sociobiology"
] |
71,968,683 | https://en.wikipedia.org/wiki/Competence%20factor | The ability of a cell to successfully incorporate exogenous DNA, or competency, is determined by competence factors. These factors consist of certain cell surface proteins and transcription factors that induce the uptake of DNA.
Natural competence is the ability of a cell to bind to and transport extracellular DNA through the membrane and recombine foreign genes into its own DNA through a process called transformation. Horizontal gene transfer is a result of this, where bacterial genes can be transferred amongst same-generation species in a given environment, and competence is the ability of a cell to participate in the transfer. If one cell in a population living in an unfavorable environment has a mutation that results in better survivability, that gene can be passed on to other competent cells to extend the same advantage. Plasmids, commonly used in genetic manipulation, can also be shared through horizontal gene transfer, which is especially relevant in modern medicine concerning the exchange of antibiotic-resistant plasmids.
A cell's competence can be determined by its genetics, which is the case for natural competency, or it can be manipulated in order to achieve artificial competence.
There are two types of competence-inducing pheromones, these are ComX and CSF. ComX is a ten amino acid oligopeptide; it requires two co-components, ComP, an histidine kinase, and ComA, a cytoplasmic response regulator. ComX binds to ComP on the outside of the inner membrane; ComP autophosphorylates and the phosphoric group is transferred to ComA. This activates transcription of genes in the competence pathway. CSF is a five amino acid oligopeptide and is exported via the GSP pathway. CSF enters the cell through oligopeptide permeate and stimulates the competence pathway at low concentrations (1-5 nM); at high concentrations (>20 nM) competence is inhibited and sporulation is stimulated.
Types of competence
Natural
Most bacterium found in nature are said to be naturally competent, meaning that they are genetically predisposed to be able to uptake foreign DNA.
Artificial
In a laboratory setting, cells are often forced into a state of artificial or induced competence, in an attempt to recreate the conditions of a microbe's natural environment. Forcing competence on bacteria can be done in two ways- one method is a process called chemo-competence. In the laboratory, cells are prepared with ice-cold calcium chloride solutions and become chemically competent. When these cells are then heat shocked (ex., 30 seconds at 42 degrees Celsius), they are able to take up both single or double stranded DNA and can either incorporate it into their genome, or the DNA can exist as a plasmid within the cell. The other method of inducing bacterial competence is a process called electro-competence, and this is done by preparing cells with low-ionic strength buffer. These cells are then treated with an electric shock to make them more permeable, and this allows them to uptake single or double stranded DNA and incorporate it into their genome or have the DNA exist as a plasmid within the cell.
Factors determining competence
Streptococcus pneumoniae gains its competence through the inducer peptide competence-stimulating peptide (CSP). As a resident in the nasopharynx, S. pneumoniae's ability to uptake antibiotic-resistant plasmids can cause dangerous infections. S. pneumoniae excretes small soluble molecules called autoinducers that contain the ability to express genetic competence in other cells. Autoinducers are used as a type of quorum sensing, which will "sense" the population of cells in the surrounding area.
Campylobacter jejuni is not competent until the exogenous genetic material is confirmed by the cell to be Campylobacter jejuni DNA. Similar circumstances also occur for Bacillus subtilis, and even then competence develops only in certain media.
Pasteurellaceae and Neisseriaceae species tend to select for genes from close relatives.
Regulation
srfA operon regulation
All cellular components that are involved in sensing extracellular factors affect the srfA operon. The expression of srfA will bypass the need for transcription of DNA for only upstream genes. This means that transcription is not exclusive to the direction of DNA it would normally follow, allowing exogenous DNA to be transcribed into the genome. srfA is coupled with an open reading frame, comS. When this reading frame is expressed, it will activate the transcription factor ComK. After ComK is activated, transcription of genes that encode all the necessary components for natural competence will begin. The expression of both srfA and comS represent a different stage of competence regulation. Without srfA, comS cannot be expressed. Without the expression of comS, the transcription and subsequent translation of the cellular components that are needed to accept and integrate exogenous DNA cannot be made.
COM-blockers
Competence can be blocked in S. pneumoniae via the mechanism of COM-blockers which disrupt the proton motive force, which is essential to ATP production. COM-blockers are compounds that inhibit the activity of luciferase, and PROG and TCL - two examples of COM-blockers - decrease the internal pH and thus decrease intracellular potassium levels. PIM does not change internal pH, but does affect the uptake of K+.
Benefits
DNA, consisting of deoxynucleotides, can be a convenient source of nutrition, and if not incorporated into the cell's own genome can provide necessary materials for cell replication. A majority of DNA that a cell uptakes is in fact not incorporated into the genome, but instead broken down and repurposed. Competent cells that more readily absorb environmental DNA, can greatly benefit from this.
If successfully transformed, bacteria may gain evolutionary advantages from the incorporated DNA, as mutations and genes causing better survivability can be shared in this way.
Absorption of DNA by competent cells can also contribute to DNA repair by creating a template for recombination, which has been specifically observed in Sulfolobus spp.
References
Bacterial genetics
Evolutionary biology terminology | Competence factor | [
"Biology"
] | 1,276 | [
"Evolutionary biology terminology",
"Bacterial genetics",
"Genetics by type of organism",
"Bacteria"
] |
71,972,078 | https://en.wikipedia.org/wiki/Global%20Ocean%20Ship-based%20Hydrographic%20Investigations%20Program | GO-SHIP (The Global Ocean Ship-based Hydrographic Investigations Program) is a multidisciplinary project to monitor ocean/climate changes. So far, this program has involved twelve countries and completed/planned 116 cruises. Participation countries are United States, United Kingdom, Japan, Canada, Germany, Spain, Australia, Norway, France, South Africa, Ireland and Sweden. Most of the cruises are completed by United States, United Kingdom, Japan, Canada, Germany and Spain.
Background
During 1872 and 1876, Challenger expedition started the modern marine survey and marked the foundation of oceanography. Since then, scientific exploration of the oceans have made many discoveries. At the end of the 19th century, America built the to carry out ocean surveys. In 1893, Norwegian scientist Fridtjof Nansen fixed his Fram in the Arctic ice-cap for three years to undertake long-term observations of oceanographic, meteorological and astronomical data.<ref>Apsley Cherry-Garrard, '[The Worst Journey in the World, Carroll & Graf Publishers, 1922, p. xxii</ref> One of the first acoustic measurements of the ocean floor was in 1919. From 1925 to 1927, the Meteor'' expedition used echo sounders to measure 70000 ocean depth measurements and explore the Mid-Atlantic Ridge. In 1953, Maurice Ewing and Bruce Heezen discovered the global ridge system extending along the Mid Atlantic Ridge. In 1960, Harry Hammond Hess developed the seafloor spreading theory by ocean exploration.Deep Sea Drilling Project started in 1968.
In the recent years, oceanographic investigation has revealed that ocean environment is changing, like Ocean acidification, water temperature, Carbon cycle, Sea level rise. Oceanographers are trying to find solutions to these changes by ocean exploration. However, it is hard to understand the whole system in one single subject because the ocean environment is balanced by both its physical conditions and chemical conditions, which is an essential factor for the diversities of marine biology. For example, if the temperature in the ocean surface rises, it would affect the Nutrients distributions, Mixed layer depth, Ocean current, pH conditions, Salinity distributions and so on. Those series of ocean environment changes could even cause dramatic decrease of some Species and effect on the entire Food web in the ocean. Scientists have many assumptions and predictions about the consequences of climate changes in ocean but only by long-term ocean exploration can testify these assumptions.
On the other hand, the ocean is large, which accounts for about 97.2% of the Earth's water resources and covers more than 70% of the Earth's surface (Water distribution on Earth), and connected with each other. If one of the oceans changes, the others would also be influenced. Thus it is necessary to use global ocean data to measure how one change can have influence on the others. However, ocean exploration is costly and no one single country can afford continuous yearly global ocean cruises themselves. Therefore, GO-SHIP as one of global ocean observation and exploration programs was launched. Except for GO-SHIP, there are other programs such as World Ocean Circulation Experiment, Tropical Ocean Global Atmosphere program, Argo (oceanography), NPOCE, Global Ocean Observing System and International Ocean Discovery Program.
Contributions and discoveries
GO-SHIP data have suggested that from the 1990s to 2000 the deep (z > 2000 m) has warmed by absorbing some of the extra heat in system... The GO-SHIP global sampling has proven that the warming is obviously larger in regions of the Antarctic Bottom Water (AABW) especially the Southern Ocean near AABW
An anthropogenic storage rate of 2.9 (± 0.4) Pg C year-1 for the most recent decade. An ocean mean annual uptake rate equates to approximately 27% of the total anthropogenic carbon emissions over 1994 to 2010.
Global Cruise Plan
The Cruise Plan includes completed and planned during 2014–2027.The table was updated in May 2022
References
Oceanography
Research projects
Oceanographic expeditions | Global Ocean Ship-based Hydrographic Investigations Program | [
"Physics",
"Environmental_science"
] | 815 | [
"Oceanography",
"Hydrology",
"Applied and interdisciplinary physics"
] |
71,972,797 | https://en.wikipedia.org/wiki/Fast%20endophilin-mediated%20endocytosis | Fast endophilin-mediated endocytosis (FEME) is an endocytic pathway found in eukaryotic cells. It requires the activity of endophilins as well as dynamins, but does not require clathrin.
In Clathrin-dependent endocytic pathways, endosomes budding from the cell membrane into the cell will form in clathrin pits, and be coated by clathrin triskelions. In FEME however, endosomes form when coated by actin, and internalise endophilin A2.
Function
Each endocytic pathway focuses on a particular component, and FEME is primarily involved in transporting receptors. These include receptors for acetylcholine and IL-2.
Associated proteins
EGFR
HGFR
VEGFR
PDGFR
NGFR
IGF1R
SHIP1
SHIP2
References
Molecular biology
Cellular processes | Fast endophilin-mediated endocytosis | [
"Chemistry",
"Biology"
] | 187 | [
"Biochemistry",
"Cellular processes",
"Molecular biology"
] |
71,972,809 | https://en.wikipedia.org/wiki/Caitlin%20Casey | Caitlin M Casey is an observational astronomer and associate professor at the University of Texas at Austin. She is known for her work in extragalactic astrophysics; she works on the formation and evolution of massive galaxies in the early Universe.
Education and career
Casey's interest in astronomy began as a child when she was given the opportunity to visit the planetarium in Rock Bridge High School in her hometown of Columbia, Missouri.
Casey completed her bachelor's degrees in physics, astronomy and applied mathematics from the University of Arizona in 2007. She attributes her decision to attend Arizona from first attending their Astronomy Camp during high school. She then obtained her Ph.D. in Astronomy from the University of Cambridge in 2010 under a Gates Cambridge Scholarship. While in Cambridge she served as president of the Gates Scholars' Society from 2009-2010. Casey was subsequently a NASA Hubble Postdoctoral Fellow at the Institute for Astronomy, University of Hawai’i at Mānoa, and then she spent two years as a postdoc at the University of California, Irvine as a McCue Postdoctoral Fellow of Cosmology. Casey became assistant professor in the Department of Astronomy at the University of Texas at Austin in 2015. Since 2021, Casey is an associate professor.
Career and research
Casey is known for her research on galaxy formation and evolution, specifically on the most massive and luminous galaxies in the Universe. While in Hawaii, she examined the formation of starburst galaxies, research that was conducted with the largest spectroscopic survey using the W.M. Keck Observatory of submillimeter-luminous galaxies detected by the Herschel Space Observatory. While at the University of California, Irvine Casey authored a review paper on star-forming galaxies. Casey is principal investigator of the COSMOS-Web Survey and the Cosmic Evolution Survey. This work is a collaborative effort with Jeyhan Kartaltepe. The COSMOS-Web Survey is a James Webb Space Telescope NIRCam imaging program that aims to reveal the sources of cosmic reionization and was the telescope's largest allocated project in its first year of observations. She presented the initial results of her research with the COSMOS-Web survey in 2023.
Casey is an advocate for equity in STEM, creating the TAURUS program, a summer research experience for marginalized students in the summer of 2016. This program is hosted at the University of Texas at Austin at the McDonald Observatory and allows under-represented undergraduate students to get involved with astronomical research. Casey created a workshop designed to spread awareness about bullying, microaggressions and harassment for academic researchers with her colleague Kartik Sheth called The Ethical Gray Zone in 2013.
Selected publications
Honors and awards
Casey received the 2018 Newton Lacy Pierce Prize awarded by the American Astronomical Society for impactful work in observational astronomy achieved before age 36. In 2019 she was awarded a Cottrell Scholar Award from the Research Corporation for Science Advancement.
References
External links
Living people
Scientists from Columbia, Missouri
Rock Bridge High School alumni
University of Arizona alumni
Alumni of the University of Cambridge
University of Texas at Austin faculty
Women astronomers
Year of birth missing (living people) | Caitlin Casey | [
"Astronomy"
] | 623 | [
"Women astronomers",
"Astronomers"
] |
71,972,962 | https://en.wikipedia.org/wiki/List%20of%20Art%20Deco%20architecture%20in%20Oregon | This is a list of buildings that are examples of the Art Deco architectural style in Oregon, United States.
Eugene
Knight Library, Eugene, 1937
McCracken Brothers Motor Freight Building, Eugene, 1946
Schaefers Building, Eugene, 1929
United States Post Office, Eugene, 1939
W.O.W. Hall, Eugene, 1932
Grants Pass
Grants Pass Steam Laundry, Grants Pass, 1903
Redwoods Hotel, Grants Pass, 1926
Rogue Theatre, Grants Pass, 1938
Gresham
Gresham High School Agricultural Building, Gresham, 1940
Gresham High School Auditorium, Gresham, 1940
Gresham High School Gymnasium, Gresham, 1940
Hood River
Butler Bank, Hood River, 1924
Keir Medical Building, Hood River, 1927
United States Post Office, Hood River, 1935
Klamath Falls
First National Bank, Klamath Falls, 1930
Golden Rule (former JC Penney Building), Klamath Falls, 1937
Klamath County Armory and Auditorium (now Klamath County Museum), Klamath Falls, 1935
Oregon Bank Building, Klamath Falls, 1929
Ross Ragland Theater (former Esquire Theater), Klamath Falls, 1940
United States National Bank, Klamath Falls, 1937
Winema Hotel, Klamath Falls, 1930
Medford
Central Medford High School, Medford, 1931
Cora Knight Addition, Medford, 1930s
Craterian Theater, Medford, 1924
Fluhrer Bakery Building, 29 North Holly Street, Medford, 1933
Hamlin Building East, Medford, 1886 and 1939
Harry & David Building, Medford, 1937
Hight Realty, Medford, 1947
Holly Theatre, Medford, 1930
Hubbard Hardware/Woods Building, Medford, 1913 and 1941
J. C. Penney Building, Medford, 1948
Jackson County Courthouse, Medford, 1932
Johnson Market Groceteria, Medford, 1927
Leever Motor Company, Medford, 1947
Pacific Greyhound Bus Depot, Medford, 1948
Safeway/Littrell Auto Parts, Medford, 1936, 1945
Tayler–Phipps Building (now a shoe store), Medford, 1909 and 1937
Vawter–Brophy Building, Medford, 1907 and 1940s
Warner, Wortman & Gore Building, Medford, 1900 and 1927
Washington Elementary School, 610 South Peach Street, Medford, 1931 and 1949
Winetrout/Crater Lake Ford Building, Medford, 1946
Young/Humphrey Motors, Medford, 1936
Portland
Aladdin Theatre, Portland, 1927
Avalon Theater, Portland, 1925
Bagdad Theatre, Portland, 1927
Bertha M. and Marie A. Green House, Portland, 1937
Canterbury Castle, Portland, 1931
Capri Apartments, Alphabet Historic District, Portland 1932
Charles F. Berg Building, Portland, 1902 and 1930
Coca-Cola Building, Portland, 1941
Commodore Hotel, Portland, 1925
Eastside Mortuary Building, Portland, 1930
Hollywood Theatre, Portland, 1926
Jantzen Knitting Mills Company Building, Portland, 1929
Jeanne Manor Apartment Building, Portland, 1931
Jensen Investment Company Building, Portland, 1930
Harry A. and Gerda Johnson Building, Kenton Commercial Historic District, Portland, 1922
Kenyon Building, Kenton Commercial Historic District, Portland, 1951
Laurelhurst Theater, Portland, 1923
Metropolitan Apartments, Portland, 1930
Moreland Theatre, Portland, 1926
Morris & Lizzie Goldstein Building, Kenton Commercial Historic District, Portland, 1923
Park Regent Apartments, Portland, 1930
Portland Art Museum, Portland, 1932
Regent Apartments, Portland, 1937
Roseway Theater, Portland, 1924
St. Johns Signal Tower Gas Station, Portland, 1954
Sunshine Dairy Plant, Portland, 1936
Terminal Sales Building, Portland, 1927
Volunteers of America, East Portland Grand Avenue Historic District, Portland, 1930
Salem
Corban University Library, Salem, 1935
Elsinore Theatre, Salem, 1926
Grand Theatre (former Grand Drugs and International Order of Odd Fellows Building), Salem, 1900 and 1947
Old West Salem City Hall, Salem, 1935
Oregon State Capitol, Salem, 1936
State Library of Oregon, Salem, 1939
Other cities
Alger Theatre, Lakeview, 1940
Ashland Springs Hotel, Ashland, 1925
Baker City Tower, Baker City, 1929
Big Creek Bridge, Heceta Head, 1931
Cameo Theatre, Newberg, 1937
Captain Robert Gray School, Astoria
Celebration Center (former Port Theater), North Bend
City Hall, Mt. Angel
Clackamas County Courthouse, Oregon City, 1936
Coos Art Museum (former Marshfield Post Office), Coos Bay, 1936
Corvalis High School, Corvallis, 1935
Cottage Grove Armory, Cottage Grove, 1931
Dayton High School, Dayton, 1935
Eltrym Theater, Baker City, 1940
Forest Theatre, Forest Grove
Harbor Theatre, Florence, 1938
Harney County Courthouse, Burns, 1940
Hub Department Store Building, Coos Bay, 1926 and 1941
The Hub Restaurant (now Surefire Design), Albany, 1940s
Isaac Lee Patterson Bridge, Gold Beach to Wedderburn, 1932
John Jacob Astor Hotel, Astoria, 1923
Joy Cinema & Pub, Tigard, 1939
Kuhn Cinema, Lebanon, 1935
Leaburg Power Plant, Lane County, 1930
Mack Theater, McMinnville, 1942
Marshfield High School, Coos Bay, 1939
Midway Theatre, Newport
Milton Odem House, Redmond, 1941
Owyhee Dam, Adrian, 1932
Palace Theatre, Silverton, 1935
Pine Theater, Prineville, 1938
Rio Theatre, Sweet Home, 1950
Seaside Building, Seaside
Siuslaw River Bridge, Florence, 1936
Springdale School, Springdale, 1931
Springfield Motors Buick Dealership, Springfield, 1952
Ten Mile Creek Bridge, Lane County, 1931
Tillamook City Hall (former Tillamook Post Office), Tillamook, 1942
Toledo History Center (former Toledo City Hall), Toledo
Tower Theater, Bend, 1940
Union Pacific Station, Nyssa, 1940s
United States Post Office, Ontario
Varsity Theatre, Ashland, 1937
Vista House, Corbett, 1918
Wilson River Bridge, Tillamook, 1931
See also
List of Art Deco architecture
List of Art Deco architecture in the United States
References
"Art Deco & Streamline Moderne Buildings." Roadside Architecture.com. Retrieved 2019-01-03.
Cinema Treasures. Retrieved 2022-09-06
"Court House Lover". Flickr. Retrieved 2022-09-06
"New Deal Map". The Living New Deal. Retrieved 2020-12-25.
"SAH Archipedia". Society of Architectural Historians. Retrieved 2021-11-21.
External links
Art Deco
Lists of buildings and structures in Oregon | List of Art Deco architecture in Oregon | [
"Engineering"
] | 1,313 | [
"Architecture lists",
"Architecture"
] |
71,975,313 | https://en.wikipedia.org/wiki/ReRites | ReRites (also known as RERITES, ReadingRites, Big Data Poetry) is a literary work of "Human + A.I. poetry" by David Jhave Johnston that used neural network models trained to generate poetry which the author then edited. ReRites won the Robert Coover Award for a Work of Electronic Literature in 2022.
About the project
The ReRites project began as a daily rite of writing with a neural network, expanded into a series of performances from which video documentation has been published online, and concluded with a set of 12 books and an accompanying book of essays published by Anteism Books in 2019. In Electronic Literature, Scott Rettberg describes the early phases of the project in 2016, when it bore the preliminary name Big Data Poetry.
Jhave (the artist name that David Jhave Johnston goes by) describes the process of writing ReRites as a rite: "Every morning for 2 hours (normally 6:30–8:30am) I get up and edit the poetic output of a neural net. Deleting, weaving, conjugating, lineating, cohering. Re-writing. Re-wiring authorship: hybrid augmented enhanced evolutionary". There is video documentation of the writing process.
The human editing of the neural network's output is fundamental to this project, and Jhave gives examples of both unedited text extracts and his edited versions in publications about the project. Kyle Booten describes ReRites as "simultaneously dusty and outrageously verdant, monotonously sublime and speckled with beautiful and rare specimens".
Performances
ReRites was first shared with an audience through a series of performances where audience members and poets would participate in reading the automatically generated texts, which appeared on screen so fast that human readers could barely keep up. This has been described as allowing participants to "re-discover[..] the peculiar pleasures of being embodied", or, in Jhave's own words, as a space where human participants were "playing their wits and voices against an evocative infinite deep-learning muse".
The first performance was at Brown University's Interrupt Festival in 2019. It has been performed many times since, including at the Barbican Centre in London and Anteism Books.
Print publications
For a single year Jhave published one book of poetry from the ReRites project each month. These twelve volumes are accompanied by a book of essays, all published by Anteism Books. The accompanying essays provide critical responses to the project from poets and scholars including Allison Parrish, Johanna Drucker, Kyle Booten, Stephanie Strickland, John Cayley, Lai-Tze Fan, Nick Montfort, Mairéad Byrne, and Chris Funkhouser. Allison Parrish notes elsewhere that these paratexts to ReRites serve a legitimising function for a genre of poetry that is not yet institutionally acknowledged.
Technical details
Starting in 2016 under the name Big Data Poetry, Jhave generated poems using, in his own words, "neural network code (..) adapted from three corporate github-hosted machine-learning libraries: TensorFlow (Google), PyTorch (Facebook), and AWSD (SalesForce)". He explains that the "models were trained on a customised corpus of 600,000 lines of poetry ranging from the romantic epoch to the 20th century avant garde". Jhave maintains a GitHub repository with some of the code supporting ReRites.
Reception
ReRites is described by John Cayley as "one of the most thorough and beautiful" poetic responses to machine learning. The work's influence on the field of electronic literature was acknowledged in 2022, when the work won the Electronic Literature Organization's Robert Coover Award for a Work of Electronic Literature. The jury described ReRites as particularly poignant in the time of the pandemic, as it was "a documentation of the performance of the private ritual of writing and the obsessive-compulsive need for writers to communicate — even when no one else is reading".
The question of authorship and voice in ReRites has been raised by several critics. Although generated poetry is an established genre in electronic literature, Cayley notes that unlike the combinatory poems created by authors like Nick Montfort, where the author explicitly defines which words and phrases will be recombined, ReRites has "not been directed by literary preconceptions inscribed in the program itself, but only by patterns and rhythms pre-existing in the corpora". In an essay for the Australian journal TEXT, David Thomas Henry Wright asks how to understand authorship and authority in ReRites: "Who or what is the authority of the work? The original data fed into the machine, that is not currently retrievable or discernible from the final works? The code that was taken and adapted for his purposes? Or Jhave, the human editor?" Wright concludes that Jhave is the only actor with any intentionality and therefore the authority of the work. The centrality of the human editor is also emphasised by other scholars. In a chapter analysing ReRites Malthe Stavning Erslev argues that the machine learning misrepresents the dataset it is trained on.
While ReRites uses 21st century neural networks, it has been compared to earlier literary traditions. Poet Victoria Stanton, who read at one of the ReRites performances, has compared ReRites to found poetry, while David Thomas Henry Wright compares it to the Oulipo movement and Mark Amerika to the cut-up technique. Scholars also position ReRites firmly within the long tradition of generative poetry both in electronic literature and print, stretching from the I Ching, Queneau's Cent Mille Milliards de Poemes and Nabokov's Pale Fire to computer-generated poems like Christopher Strachey's Love Letter Generator (1952) and more contemporary examples.
Jhave describes the process of working with the output from the neural network as "carving". In his book My Life as an Artificial Creative Intelligence, Mark Amerika writes that the "method of carving the digital outputs provided by the language model as part of a collaborative remix jam session with GPT-2, where the language artist and the language model play off each other’s unexpected outputs as if caught in a live postproduction set, is one I share with electronic literature composer David Jhave Johnston, whose AI poetry experiments precede my own investigations."
References
2010s electronic literature works
New media
21st-century poetry
Canadian poetry
Natural language processing
Generative literature
Canadian electronic literature works | ReRites | [
"Technology"
] | 1,358 | [
"Multimedia",
"Natural language processing",
"New media",
"Natural language and computing"
] |
71,976,758 | https://en.wikipedia.org/wiki/Citrus%20chlorotic%20dwarf-associated%20virus | Citrus chlorotic dwarf-associated virus (CCDaV, genus Citlodavirus, family Geminiviridae) has been so far found in Turkey, China, and Thailand. Isolates from the three countries are genetically highly identical. CCDaV is currently considered as an emerging virus that threatens citrus plantations in the Mediterranean region.
References
Viral plant pathogens and diseases
Geminiviridae | Citrus chlorotic dwarf-associated virus | [
"Biology"
] | 77 | [
"Virus stubs",
"Viruses"
] |
71,977,359 | https://en.wikipedia.org/wiki/HD%2026670 | HD 26670, also known as HR 1305, is a star located in the northern circumpolar constellation of Camelopardalis, the giraffe. The object has been designated as 26 H. Camelopardalis, but is not commonly used in modern times. It has an apparent magnitude of 5.70, allowing it to be faintly visible to the naked eye. Based on parallax measurements from Gaia DR3, the object is estimated to be 491 light years away from the Solar System. It appears to be slowly receding with a heliocentric radial velocity of .
Characteristics
This is a solitary, bluish-white hued B-type main-sequence star with a stellar classification of B7 V. It has also been given a class of B5 Vn with the addition of broad or nebulous absorption lines due to rapid rotation. It has 4 times the mass of the Sun and is estimated to be 57 million years old, having completed only a quarter of its main sequence lifetime. HD 26670 has 2.86 times the radius of the Sun and an effective temperature of . When combined, these parameters yield a luminosity 244 times greater than the Sun's from its photosphere. Like most hot stars, HD 26670 spins rapidly, having a projected rotational velocity of . Huang et al. (2010) give it a velocity of , which is 72% of its breakup velocity. As a result, the surface gravity is greater at the poles rather than the equator and it has an oblate shape.
Notes
References
B-type main-sequence stars
026670
Camelopardalis
019968
1305
BD+61 00387 | HD 26670 | [
"Astronomy"
] | 347 | [
"Camelopardalis",
"Constellations"
] |
71,977,893 | https://en.wikipedia.org/wiki/HD%2050885 | HD 50885, also known as HR 2581, is a star located in the northern circumpolar constellation Camelopardalis, the giraffe. It has an apparent magnitude of 5.69, making it faintly visible to the naked eye if viewed under ideal conditions. Based on parallax measurements from Gaia DR3, the object is estimated to be 513 light years distant. It appears to be approaching the Solar System with a heliocentric radial velocity of .
This is a solitary, evolved red giant star with a stellar classification of K4 III. It is currently on the red giant branch, fusing a hydrogen shell around an inert helium core. It has 1.32 times the mass of the Sun but has expanded to 30.4 times its girth. It radiates 203 times the luminosity of the Sun from its photosphere at an effective temperature of . HD 50885 has an iron abundance only 102% that of the Sun, placing it at solar metallicity.
There is an optical companion located away along a position angle of 357°. This object was first noticed by Robert S. Ball in 1879
References
Camelopardalis
Double stars
K-type giants
050885
033827
2581
BD+70 00430 | HD 50885 | [
"Astronomy"
] | 263 | [
"Camelopardalis",
"Constellations"
] |
71,978,048 | https://en.wikipedia.org/wiki/Time%20in%20the%20Bahamas | The Bahamas observes Eastern Standard Time Zone (UTC−5) as standard time, and Eastern Daylight Time (UTC−4) as daylight saving time (DST). DST is observed annually from the second Sunday in March to the first Sunday in November.
IANA time zone database
In the IANA time zone database, the Bahamas is given one zone in the file zone.tab—America/Nassau. "BS" refers to the country's ISO 3166-1 alpha-2 country code. Data for the Bahamas directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
References
External links
Current time in the Bahamas at Time.is
Time in the Bahamas at TimeAndDate
Time by country
Geography of the Bahamas
Time in North America | Time in the Bahamas | [
"Physics"
] | 165 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
71,979,678 | https://en.wikipedia.org/wiki/A%C3%B1ana%20Diapir | The Añana Diapir (, ) is a diapir in Álava, Basque Country, Spain. Two notable wetlands are located within the diapir: the Salt Valley of Añana and Lake Arreo. It was declared a protected biotope by the Basque Government in 2016, and redesignated as a protected natural landscape in 2023.
Geology
The Añana Diapir was formed by evaporites from the Keuper which ascended through Jurassic, Cretaceous and Tertiary layers. Other types of rocks were carried together with the evaporites, notably ophites. Clay, marl and gypsum are also present in the diapir. The hydrogeological system of the diapir is complex. The saline water that flows through the Salt Valley results of the mixing of (at least) two types of water: superficial waters from the eastern part of the diapir and deeper waters from the western part (the ones which make the spring water saline).
Flora and fauna
In the hypersaline waters of the Salt Valley, the only animals present are Artemia parthenogenetica and Ochthebius notabilis, with more species in areas of lower salinity. Lake Arreo is home to four fish species, and several bird species have been observed in its vicinity.
About half of the diapir is covered by forests, consisting mostly of Pinus sylvestris and Quercus faginea. Several hydrophytes are found in Lake Arreo, while its shores are covered by common reed and other plants. Several halophilic plant species are present in the Salt Valley.
References
External links
2016 establishments in the Basque Country (autonomous community)
Geography of Álava
Landforms of the Basque Country (autonomous community)
Protected areas established in 2016
Protected areas of the Basque Country (autonomous community)
Salt domes | Añana Diapir | [
"Chemistry"
] | 378 | [
"Salt domes",
"Salts"
] |
71,980,146 | https://en.wikipedia.org/wiki/Glossary%20of%20mycology | This glossary of mycology is a list of definitions of terms and concepts relevant to mycology, the study of fungi. Terms in common with other fields, if repeated here, generally focus on their mycology-specific meaning. Related terms can be found in glossary of biology and glossary of botany, among others. List of Latin and Greek words commonly used in systematic names and Botanical Latin may also be relevant, although some prefixes and suffixes very common in mycology are repeated here for clarity.
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
R
S
T
U
V
W
X
Y
Z
See also
List of mycologists
Outline of fungi
Outline of lichens
Glossary of lichen terms
References
Bibliography
Mycology
mycology
Wikipedia glossaries using description lists | Glossary of mycology | [
"Biology"
] | 163 | [
"Mycology",
"Glossaries of biology"
] |
71,981,306 | https://en.wikipedia.org/wiki/List%20of%20Art%20Deco%20architecture%20in%20Georgia%20%28U.S.%20state%29 | This is a list of buildings that are examples of the Art Deco architectural style in Georgia, United States.
Atlanta
7 Stages Theatre (former Little 5 Points Theatre), Atlanta, 1940
Atlanta City Hall, Atlanta, 1930
Cheshire Square Shopping Center, Atlanta, 1967
Empire Manufacturing Company Building, Atlanta, 1939
Evans Cucich House, Atlanta, 1935
Forsyth Walton Building, Atlanta, 1936
Freeman Ford Building, Atlanta, 1930
GLG Grand, Atlanta, 1992
Healey Building, Atlanta, 1920
Lerner Shops, Atlanta
Majestic Diner, Atlanta, 1929
Martin Luther King, Jr. Federal Building, Atlanta, 1933
Municipal Auditorium, Atlanta, 1909
Nabisco Plant, Atlanta, 1955
National NuGrape Company, Atlanta, 1937
Olympia Building, Atlanta, 1936
Plaza Theater, Atlanta, 1939
Regenstein's, Atlanta
Rhodes Haverty Building, Atlanta
Southern Bell Telephone Company Building, Atlanta, 1929
Southern Dairies, Atlanta, 1939
Telephone Factory Lofts, Atlanta, 1938
Ten Park Place, Atlanta, 1930
Troy-Peerless Laundry Building, Atlanta, 1929
United States Post Office, Federal Annex, Atlanta, 1933
Variety Playhouse, Atlanta, 1940
W. W. Orr Building, Atlanta, 1930
William–Oliver Building, Atlanta, 1930
Gainesville
Dixie Hunt Hotel, Gainesville, 1937
Logan Building, Gainesville, 1929
Old Hall County Courthouse, Gainesville, 1937
Savannah
Globe Shoe Company, Savannah, 1929
Karpf Building, Savannah
The Savannah Theatre, Savannah, 1958
Tifton
Jenny's Fashion, Tifton Commercial Historic District, Tifton
Lockeby Building, Tifton Commercial Historic District, Tifton, 1937
Tift Theater, Tifton, 1937
Other cities
Albany Insurance Mart, Albany, 1950s
Bacon Theatre, Alma, 1946
Blackshear Bank Building, Blackshear, 1930s
Blair Rutland Building, Decatur, 1925
Campus Theatre, Milledgeville
Coffee County Courthouse, Downtown Douglas Historic District, Douglas, 1940
Colquitt Theater, Colquitt Town Square Historic District, Colquitt
Colquitt Theater, Moultrie Commercial Historic District, Moultrie, 1941
Dosta Theater, Valdosta, 1941
Dublin Theatre, Dublin, 1934
Earl Smith Strand Theater, Marietta, 1935
Early County Jail, Blakely Court Square Historic District, Blakely, 1940
Fickling Lodge No. 129, Butler, 1920
Friedlander's Building, Moultrie, 1936
Georgia Theater (now Emma Kelly Theater in the Averitt Center for the Arts), Statesboro, 1936
Grand Theater, Fitzgerald, 1936
Hogansville City Hall (former Royal Theater), Hogansville, 1937
Holly Theatre, Dahlonega, 1948
Liberty Theater, Columbus, 1925
Martin Theatre (now Martin Centre), Downtown Douglas Historic District, Douglas, 1939
Miller Theatre, Augusta, 1938
Mitchell County Courthouse, Camilla Commercial Historic District, Camilla, mid-1930s
Monroe City Hall, Monroe, 1939
Montezuma Motor Company, Montezuma, 1920s
Montgomery Ward Building, Griffin Commercial Historic District, Griffin, 1929
Ocmulgee National Monument Visitor Center, Macon, 1936
Pickens County Courthouse, Jasper, 1949
Pine Theatre, Fitzgerald, 1945
Playhouse Theater, Valdosta, 1941
Ritz Theater, Thomaston, 1927
Ritz Theatre at the Schaefer Center, Toccoa, 1939
Royal Cafe, Quitman Historic District, Quitman, 1913
Southeast Georgian Building, Kingsland Commercial Historic District, Kingsland, 1925
Southern Trust Building, Macon, 1941
State Theatre, Albany, 1945
Strand Dinner Cinema, Jesup, 1920s
Suwanee City Hall (Town Center), Suwanee, 2002
Sylvia Theatre & Granitoid Office Building, Sylvania
Tom Huston Frozen Foods Company–Montezuma Motor Company, Montezuma, 1920
Troup County Courthouse, Annex, and Jail, LaGrange, 1939
United States Post Office, Decatur, 1935
Walker Theatre, Fort Gaines, 1936
West Theatre, Cedartown, 1941
Wink Theater, Dalton Commercial Historic District, Dalton, 1938
Zebulon Theater, Cairo, 1936
See also
List of Art Deco architecture
List of Art Deco architecture in the United States
References
"Art Deco & Streamline Moderne Buildings." Roadside Architecture.com. Retrieved 2019-01-03.
Cinema Treasures. Retrieved 2022-09-06
"Court House Lover". Flickr. Retrieved 2022-09-06
"New Deal Map". The Living New Deal. Retrieved 2020-12-25.
"SAH Archipedia". Society of Architectural Historians. Retrieved 2021-11-21.
External links
Art Deco
Lists of buildings and structures in Georgia (U.S. state) | List of Art Deco architecture in Georgia (U.S. state) | [
"Engineering"
] | 930 | [
"Architecture lists",
"Architecture"
] |
71,981,420 | https://en.wikipedia.org/wiki/List%20of%20Art%20Deco%20architecture%20in%20Washington%20%28state%29 | This is a list of buildings that are examples of the Art Deco architectural style in Washington, United States.
Bremerton
Admiral Theater, Bremerton, 1942
Pacific Planetarium (former Fire Station No. 1), Bremerton, 1939
Roxy Theater, Bremerton, 1941
Valentinetti Puppet Museum (former Seattle-First National Bank)
Longview
Big Four Furniture Building (former Lumberman's Bank), Longview, 1934
Pacific Telephone and Telegraph Building, Longview, 1928
Stageworks Theatre, Longview, 1941
Seattle
1411 4th Avenue Building, Seattle, 1928
Admiral Theater, Seattle, 1919, 1942
Exchange Building, Seattle, 1929
Federal Office Building, Seattle, 1932
Fire Station No. 6, Seattle (now replaced by newer station)
Fire Station No. 41, Magnolia Neighborhood, Seattle, 1936
Hartford Building (now a coffee shop), Seattle
Jewel Box Theatre, Seattle, 1932
Macy's (former Bon Marché), Seattle, 1929
Naval Reserve Armory, Seattle, 1942
Pacific Tower, Seattle, 1932
Sanctuary at Admiral, Seattle, 1929
Schmitz Park Bridge, Seattle, 1936
Seattle Asian Art Museum, Seattle, 1933
Seattle Tower (former Northern Life Tower), Seattle, 1927
SIFF Cinema Uptown (former Uptown Theatre), Seattle, 1926 and 1940s
United Shopping Tower, Seattle, 1929
Varsity Theatre, Seattle, 1921
Washington Athletic Club, Seattle, 1930
Spokane
City Ramp Garage, Spokane, 1928
Felts Field, Spokane, 1932
Fox Theater, Spokane, 1931
Garland Theater, Spokane, 1945
John R. Rogers High School, Spokane, 1932
Pay'n Takit, Spokane, 1933
Sears, Roebuck Department Store, Spokane, 1929
Tacoma
Fire Station No. 2, Tacoma, 1907
Fire Station No. 5, Tacoma, 1935
Tacoma Soccer Center (former Tacoma Exposition Hall), 1940
Tacoma Municipal Building, Tacoma, 1933
USA of Yesterday (former Brus Buick Dealership), 1948
Vancouver
Clark County Courthouse, Vancouver, 194
Kiggins Theatre, Vancouver, 1936
Luepke Florist, Vancouver, 1937, 1945
Vancouver Telephone Building, Vancouver, 1934
Other cities
A. E. Larson Building, Yakima, 1931
Adams County Courthouse, Ritzville
Bellingham City Hall, Bellingham, 1939
Cascadian Hotel, Downtown Wentachee Historic District, Wentachee, 1929
Chehalis Theatre, Chehalis, 1938
Collins Building, Colville, 1937
Covington Electrical Substation, Bonneville Power Administration, Covington, 1941
D&R Theatre, Aberdeen, 1924 and 1937
Everett City Hall, Everett, 1920s
F. W. Woolworth Company Store, Renton, 1954
Ferry County Courthouse, Republic, 1936
First American National Bank Building, Port Townsend
Fox Theatre, Centralia, 1930
Kelso Theater, Kelso, 1923
Klickitat County Courthouse, Goldendale, 1942
Larson Building, Yakima
Loudon Brothers Dairy Building, Ellensburg, 1930s
National Bank of Ellensburg (now 420 Loft), Ellensburg, 1937
North Bend Theatre, North Bend, 1941
Olympic Theatre, Arlington, 1939
Omak Cinema, Omak, 1937
Pacific Telephone Building, Walla Walla, 1936
Princess Theater, Prosser, 1919 and 1940s
Renton Theatre, Renton, 1920s
Ritz Theatre, Ritzville (AKA New Ritz Theatre), 1937
Sacajawea Interpretive Center, Sacajawea State Park, Franklin, 1938
Thurston County Courthouse, Olympia, 1930
United States Post Office and Annex, Wenatchee, (now the Wenatchee Valley Museum & Cultural Center) 1918 and 1938
United States Post Office Hoquiam Main, Hoquiam, 1932
United States Post Office Lynden Main, Lynden, 1940
See also
List of Art Deco architecture
List of Art Deco architecture in the United States
References
"Art Deco & Streamline Moderne Buildings." Roadside Architecture.com. Retrieved 2019-01-03.
Cinema Treasures. Retrieved 2022-09-06
"Court House Lover". Flickr. Retrieved 2022-09-06
"New Deal Map". The Living New Deal. Retrieved 2020-12-25.
"SAH Archipedia". Society of Architectural Historians. Retrieved 2021-11-21.
"USA: Seattle's Art Deco Jewels – from Skyscraper to Fire Station". Minor Sights, November 6, 2017.. Archived from the original on 2019-01-16. Retrieved 2019-01-16.
External links
Art Deco
Lists of buildings and structures in Washington (state) | List of Art Deco architecture in Washington (state) | [
"Engineering"
] | 910 | [
"Architecture lists",
"Architecture"
] |
71,982,349 | https://en.wikipedia.org/wiki/These%20Waves%20of%20Girls | These Waves of Girls is a hypermedia novella by Caitlin Fisher that won the Electronic Literature Organization's Award for Fiction in 2001. The work is frequently taught in undergraduate literature courses and is referenced in the field of electronic literature as a significant example of early multimodal web-based hypertext fiction, placing Fisher "at the forefront of digital writing".
Plot
The plot of These Waves of Girls is described by Andreas Kitzmann as concerning "a young girl struggling with her sexual identity", while Raine Koskimaa describes the work as "a confessional autobiography about a girl coming to terms with her lesbian identity".
The "waves" of girls are "supposed to be about different moments in girlhood, different kinds of girls, different ways of discursively producing the girl. There are so many layers of stories of girls as victims, as victimisers, as cruel, as strong, as just so many different things at once", Fisher explained in a television interview in 2001.
Narrative structure and interaction
Web-based hypertext
In an interview with TechTV immediately after receiving the ELO Award for These Waves of Girls, Fisher said the experience of writing with links and multiple modalities was exciting: "Writing in a hypertext environment, and working on the links as you're working on the writing, that becomes another way of writing - I think there is a new grammar to hypermedia." However, she also noted that "what I love best about traditional writing, I could keep."
In 2001, publishing a story on the web was still fairly unusual. Koskimaa notes that this affects the experience of reading the work itself: "it situates itself in the huge docuverse of the Internet –even though there are no links from the work reaching outside of its self-contained whole, through the web browser functionality it is always just one click away from other documents in the Web".
George Landow in his 2006 textbook, Hypertext 3.0. explains that this work is link intensive and provides navigational links as well as semantic links within the text.
The hypertextual structure is what Koskimaa calls a textbook example of "associative hypertext". Larry McCaffery described the linking as working in "often surprising ways that establish hidden connections that often seem to be operating on the basis of emotional, associational logic".
Multimodal hypertext
These Waves of Girls "effectively integrates visual and audio material into a nonlinear hypertext where the reader actively determines the process of the reading experience". The integration of sound and visuals through a combination of HTML and Adobe Flash was new in 2001. Colours, images and sounds (like the laughter of girls at the beginning of the piece) are integral to the narrative. Koskimaa also notes that "[s]ome of the images are mildly interactive in a way that moving the cursor over them distorts the picture like it was 'squeezed'." Vertical and horizontal scrolling beyond the immediately visible part of the page in the browser are also utilised.
Autobiographical
Kitzmann writes that These Waves of Girls is "structured as a confessional autobiography that parallels, to some extent, the experience of someone reminiscing about childhood experiences while flipping through old photographs." This is a common way of structuring hypertext fictions, Kitzmann writes, because it is a familiar mode of storytelling that is often characterised by the storyteller's memories being triggered by "a variety of cues, such as old photographs, comments by listeners, and random daily events". Koskimaa also notes that the work uses an unreliable narrator, a familiar literary technique in fictional autobiographies.
Unpolished web design
The autobiographical framing is also visible in the slightly unpolished feel of the web design. Anja Rau has criticised this in her "beta-test" of the work, where she argues that the use of frames, Flash and the embedding of sound is done in a way that "does not meet the technological standards of current internet or CD-ROM productions." In an analysis of how people read electronic literature based on teaching the works in undergraduate and Masters level classes, James Pope noted that all students reading These Waves of Girls commented "that the interface design was messy and confusing, with cluttered layout, awkward navigation and nested frames creating very distracting pages".
Raine Koskimaa counters this argument, saying that the unpolished style "has to be taken as a conscious choice by the author". While nested frames would be unacceptable if following web design guidelines, they might "be a successful device in a hyperfictional context (..) We can interpret the instance of nested frames as a meaningful element in the work".
Larry McCaffery's description of the work in his role as judge of the fiction contest supports Koskimaa's interpretation that the unpolished web design is a meaningful narrative element. McCaffrey writes, "There is a raw energy and garish intensity to these visual features that perfectly captures the feel of childhood and adolescence."
In Digital Fiction and the Unnatural, Astrid Ensslin and Alice Bell note that another aspect making These Waves of Girls difficult to read is the way links are used: "words used as hyperlinks are not always immediately indicative of the destination lexias to which they lead, so that they can inhibit rather than empower readers in their role as link chooser."
Narrativity
Writing for the Bloomsbury Handbook of Electronic Literature, Daniel Punday argues that These Waves of Girls "locates narrativity within individual stages and sections, but eschew(s) narrative progression through these stages." Like Koskimaa, Sunday sees the structure of These Waves of Girls as strongly connected to the aesthetic and culture of the web at the turn of the century. He writes, "Fisher's narrative exemplifies the way that early Web-based hypertext could tell a series of interrelated stories using a menu system that allows the reader to enter (and reenter) sections in any order. (..) [N]arrativity exists entirely within the stories narrated and alluded to within individual alexia; the overall menu structure of the text is unconnected to narrative progression."
Reception
The Electronic Literature Organization awarded These Waves of Girls its fiction award in 2001. The judge, Larry McCaffery, wrote: "I found myself hooked on Waves from the moment I first logged on and watched Caitlin's gorgeous graphic interface assemble itself out of images of moving clouds drifting across the screen, mingling with the sounds of girls laughing." Despite this excitement, writing in 2006, James Pope notes the apparent paradox that a work so highly thought of in the field of electronic literature, and about as popular a topic as teen sexuality, "remains 'stuck' in a sort of twilight zone, apparently known only to a few insiders".
The work is frequently taught in undergraduate literature courses and is referenced in the scholarship as a highly influential example of early multimodal web-based hypertext fiction. Fisher is described as having "established herself at the forefront of digital writing" with These Waves of Girls and the augmented reality poem Andromeda (2008).
External links
2001 television interview with Caitlin Fisher on TechTV about These Waves of Girls winning the ELO Award
These Waves of Girls no longer works on the web because it uses Adobe Flash, which has been deprecated. However, the Electronic Literature Organization hosts an archival emulation of the work.
Short video walkthrough documenting These Waves of Girls
ELMCIP Knowledge Base for Electronic Literature entry for These Waves of Girls
References
2000s electronic literature works
2001 in Internet culture
2001 Canadian novels
Women in fiction
Lesbian fiction
Canadian novellas
Hypermedia
Canadian LGBTQ novels
2000s LGBTQ novels
Novels with lesbian themes
2001 LGBTQ-related literary works | These Waves of Girls | [
"Technology"
] | 1,619 | [
"Multimedia",
"Hypermedia"
] |
71,983,740 | https://en.wikipedia.org/wiki/Leucocoprinus%20viridiflavus | Leucocoprinus viridiflavus is a species of mushroom producing fungus in the family Agaricaceae. It may also be known as Leucoagaricus viridiflavus.
Taxonomy
It was first described in 1917 by the English mycologist Thomas Petch who classified it was Lepiota viridiflava.
In 2009 it was reclassified as Leucoagaricus viridiflavus by T.K. Arun Kumar and Patinjareveettil Manimohan and then reclassified again in 2012 as Leucocoprinus viridiflavus by Erhard Ludwig.
Description
Leucocoprinus viridiflavus is a small dapperling mushroom with thin yellow flesh (up to 4mm thick at the central disc) that discolours olive or green when damaged or cut.
Petch described Lepiota viridiflava as follows:
Cap: Up to 2.5 cm wide, umbonate and almost planar when expanded. The surface colour is greenish-yellow or sulphur-yellow and is coated in thin dark green patches and specks which may appear sticky when moist or shiny when dry. The central disc or umbo is a darker green than the rest of the surface. As opposed to most Leucocoprinus species which display striations at the cap edges this species is said to have an appendiculate margin, with pieces of the partial veil hanging from the cap edges. Stem: 2.5–3 cm tall and 3mm thick tapering upwards from a slightly wider base. The surface is greenish-yellow or sulphur-yellow similar to the cap and is fibrillose with dark green fibers towards the base. The interior is hollow with white fibers and yellow flesh. Gills: Free, crowded and likewise greenish-yellow or sulphur-yellow with green bruising. Spores: Ovoid and pale yellow. 5-8 x 3-4 μm.
The 2009 description of Leucoagaricus viridiflavus is similar but expands on these details:
Cap: 1.1-2.9 cm wide, conical or convex when young expanding to convex or applanate when mature. Broadly umbonate with a pastel yellow surface that is smooth or rarely has minute fibrils which are olive or the same colour as the cap surface. All parts discolour to olive and finally dark grey with bruising. The cap edges do not have striations and are incurved when young, becoming straight with age sometimes with veil fragments present. Stem: 4–7 cm tall and 2-4mm thick with a slightly bulbous base that is up to 6mm wide from which the stem may taper up from slightly or be otherwise equal in width across the length. The surface is pastel yellow and smooth but with fibers towards the base whilst the interior is solid at first but hollowing with age. The membranous stem ring is located towards the top of the step (superior) but may disappear. Gills: Free, crowded or moderately crowded and up to 4mm wide. Pastel yellow to greenish yellow with some fringing on the edges that is more noticeable with age and when viewed with a lens. Smell: Not distinctive. Spores: Ellipsoid to subamygdaliform with a germ pore that is not easily distinguished. Dextrinoid. 5.5-8.5 x 4-5 μm.
Habitat and distribution
Leucocoprinus viridiflavus is scarcely recorded and little known. The specimens described by Petch were found on the ground in flower beds in Peradeniya, Sri Lanka whilst the specimens described by Kumar and Manimohan were found in Kerala state, India where they were scattered or solitary on soil amongst decaying Acacia leaves. It was noted as appearing regularly around the Calicut University campus immediately after heavy rains during dry periods.
Similar species
There are a small number of similarly green bruising greenish-yellow species including Leucoagaricus sulphurellus, Leucocoprinus viridiflavoides, Leucoagaricus viriditinctus, Lepiota cyanescens and Leucoagaricus houaynhangensis. The genera in which they should be placed is not necessarily certain and some of these species may still be known under previous classifications within Lepiota, Leucocoprinus or Leucoagaricus or may be subject to reclassification as some of these species are poorly documented and all are scarcely observed. As the macroscopic characteristics of these species are similar and unusual within these genera it may take microscopic analysis to distinguish them.
References
viridiflavus
Fungi described in 1917
Fungi of Sri Lanka
Fungi of India
Fungus species | Leucocoprinus viridiflavus | [
"Biology"
] | 981 | [
"Fungi",
"Fungus species"
] |
71,984,125 | https://en.wikipedia.org/wiki/WD%200810%E2%80%93353 | WD 0810-353 (UPM J0812-3529) is a white dwarf currently located from the Solar System. This stellar remnant may approach the Solar System 29,000 years from now at a distance of around 0.15 parsecs, 0.49 light-years or from the Sun, crossing well within the proposed boundaries of the Oort cloud. Such close proximity will almost certainly make its flyby the closest in the future, until the flyby of Gliese 710 occurs around 1.14 million years after the dwarf's flyby.
Observations
WD 0810-353 is a dim object with an apparent magnitude of 14.5 in the southern constellation of Puppis. Its motion perpendicular to the line of sight is considerable; it is consistently listed as a high proper motion star.
Physical properties
WD 1810-353 is a white dwarf of spectral type DAH with a very strong magnetic field, perhaps as strong as . It has a mass of and an age of 2.7 billion years; its effective temperature is or . Gaia Data Release 3 (Gaia DR3) gives a value of its radial velocity of which could be incorrect because the Gaia software pipeline does not include any template for white dwarfs. Alternate analyses suggest a radial velocity as high as .
Flyby
Considering the values from Gaia DR3, WD 1810-353 will traverse the Oort cloud, disturbing the population of comets there, Given its mass such an encounter like Gliese 710, would not cause a non-negligible orbital change to the Pluto system and Neptune resonant object. Both the minimum approach distance and the timing of this flyby depend strongly on the value of the radial velocity. The Gaia DR3 mean BP/RP low-resolution spectrum suggests that WD 0810-353 could be a hypervelocity runaway white dwarf ejected during a type Ia supernova explosion. Extensive analyses show that the relative velocity during the flyby could be high enough, or the minimum approach distance large enough, to prevent any significant perturbation on the Oort cloud.
Very strong and complex magnetic field
New observational data confirmed the very strong magnetic field of this white dwarf and provided a new value of the radial velocity,. With this value, the future flyby to the Solar System is unremarkable.
Notes
References
White dwarfs
Puppis | WD 0810–353 | [
"Astronomy"
] | 489 | [
"Puppis",
"Constellations"
] |
71,985,905 | https://en.wikipedia.org/wiki/Salisbury%20Municipal%20Incinerator | The Salisbury Municipal Incinerator was a waste management system built for handling municipal waste in Salisbury, Maryland, United States. It burned trash at high temperatures, releasing toxic gasses into the atmosphere and the community. In response to increased awareness of environmental impacts, the city demolished the Incinerator and now uses other modern waste management methods.
History
The Salisbury Municipal Incinerator construction project started in 1949 and was estimated to be fully completed by September 1950. The Incinerator was a three-story structure that cost an estimated $261,000 to build. The project was commissioned due to the need for the city of Salisbury, Maryland to have a method for city-wide waste management. The city incinerator later closed down circa the 1960s. There were initial talks of turning it into a museum. Still, the site was later demolished, and the City of Salisbury Police Department was built there. The site was located on Delaware Avenue near the intersection with Route 50.
Environmental factors caused by incinerators
After its closure, Maryland state law required 23 counties to conform to a waste management plan to handle city waste better. Salisbury's solution for this state mandate was to build a landfill to handle city waste. The Environmental Service Commission spearheaded the project. The landfill project, though completed, faced several issues due to heavy rainfall and flooding, so it had to be closed until after the inclement weather. In November 1992, the Salisbury City Council was quoted an estimated cost of $16 million - $20 million to build a more extensive and efficient landfill. Waste materials dumped into landfills release toxic gasses such as methane, ammonia, sulfides, and carbon dioxide, which can contribute to climate change. In 1963, the clean air act initiated the development of a national program to reduce air pollution and protect people's public health and welfare. The 1967 Clean Air Act permitted the enforcement of regulations that impacted waste management services like the Salisbury Municipal incinerator.
Present day
The Wicomico County, Maryland Solid Waste Division is now a complex that houses buildings of various functions to enable equipment storage and a physical workplace for employees. Sixty employees work at the landfill to run its day-to-day operations, including landfill, dredging operations, and recycling. To efficiently manage daily operations, the workers utilize 85 pieces of equipment to complete daily tasks. For utmost efficiency, some of the work is contracted out when necessary. In partnership with Ingenco Wholesale Power LLC (now Archaea Energy), the Wicomico Solid Waste Division manages its landfill methane emissions by converting it to renewable energy to heat homes and businesses.
References
Incinerators
Waste management in the United States
Buildings and structures in Maryland
Landfills
Methane
Renewable energy
Recycling
Salisbury, Maryland | Salisbury Municipal Incinerator | [
"Chemistry"
] | 549 | [
"Greenhouse gases",
"Incinerators",
"Incineration",
"Methane"
] |
71,985,996 | https://en.wikipedia.org/wiki/Ferrocenecarboxylic%20acid | Ferrocenecarboxylic acid is the organoiron compound with the formula . It is the simplest carboxylic acid derivative of ferrocene. It can be prepared in two steps from ferrocene by acylation with a 2-chlorobenzoyl chloride followed by hydrolysis.
Reactions and derivatives
The pKa of ferrocenecarboxylic acid is 7.8. The acidity increases more than a thousand-fold, to pH 4.54 upon oxidation to the ferrocenium cation.
By treatment with thionyl chloride, the carboxylic acid anhydride () is produced.
Derivatives of ferrocenecarboxylic acid are components of some redox switches.
Related compounds
1,1'-Ferrocenedicarboxylic acid
Ferrocenecarboxaldehyde
References
Ferrocenes
Cyclopentadienyl complexes
Aromatic acids | Ferrocenecarboxylic acid | [
"Chemistry"
] | 191 | [
"Organometallic chemistry",
"Cyclopentadienyl complexes"
] |
71,986,072 | https://en.wikipedia.org/wiki/List%20of%20Art%20Deco%20architecture%20in%20Missouri | This is a list of buildings that are examples of the Art Deco architectural style in Missouri, United States.
Cape Girardeau
2 North Fountain, Courthouse–Seminary Neighborhood Historic District, Cape Girardeau, 1940
Broadway Theater, Broadway Commercial Historic District, Cape Girardeau, 1921
Esquire Theater, Cape Girardeau, 1947
Columbia
Columbia National Guard Armory, Columbia, 1940
Doctor's Building, Columbia, 1940s
Metropolitan Building, Eighth and Broadway Historic District, Columbia, 1930
National Guard Armory, Columbia, 1940
Hannibal
Crescent Jewelers, Hannibal, 1920s
Fifth Street Baptist Church Welcome Center, Hannibal
Kresge Building, Broadway District, Hannibal, 1931
Jefferson City
209 Adams (former A&P Grocery Store), Capitol Avenue Historic District, Jefferson City, 1939
Prince Edward Apartments, 208 Marshall, Capitol Avenue Historic District, Jefferson City, 1930
Tergin Apartment Building, Jefferson City, 1939
Kansas City
909 Walnut, Kansas City, 1931
925 Grand, Kansas City, 1921
Bartle Hall Pylons, Kansas City, 1994
F. W. Woolworth Building, Kansas City, 1928
Hotel Phillips, Kansas City
Jackson County Courthouse, Kansas City, 1934
Kansas City City Hall, Kansas City, 1937
Kansas City Convention Center, Kansas City, 1994
Kansas City Power and Light Building, Kansas City, 1931
Katz Drug Building, Kansas City, 1938
Municipal Auditorium, Kansas City, 1936
National World War I Museum and Memorial, Kansas City, 1926
St. Stephen Baptist Church, Kansas City, 1947
Switzer School, Kansas City, 1939
Tower Dry Cleaners and Laundry, Kansas City, 1944
United States Courthouse and Post Office, Kansas City, 1939
St. Joseph
901 Jules, St. Joseph, 1950
Benton High School, St. Joseph, 1940
Missouri Theater and Missouri Theater Building, St. Joseph, 1927
Regal Cinema (now furniture store), St. Joseph, 1926
Trail Theater, St. Joseph, 1951
United States Post Office and Courthouse, St. Joseph, 1938
St. Louis
A & P Food Stores Building, St. Louis, 1940
ABC Auto Sales and Investment Company Building, St. Louis, 1927
Continental Life Building, St. Louis, 1930
DeBaliviere Building, St. Louis, 1928
Fox Theatre, St. Louis, 1929
Jewel Box, St. Louis, 1936
Shell Building, St. Louis
Southwestern Bell Building, St. Louis, 1926
Tom-Boy Supermarket (now LeGrand's Market), St. Louis, 1936
Vestal Chemical Company, St. Louis, 1920s
Victor Creamery Company (now Vandeventer Building), St. Louis, 1935
Sedalia
218 Ohio, Sedalia Commercial Historic District, Sedalia
Boonslick Regional Library, Sedalia
Fox Theater Event Center, Sedalia, 1940
Missouri State Fair, Sedalia, 1941
Sedalia National Bank, 301 S. Ohio, Sedalia Commercial Historic District, Sedalia, 1929
Uptown Theatre, 225 Ohio Street, Sedalia, 1936
Other cities
66 Drive-In, Carthage, 1949
113 East Main, Fredericktown Courthouse Square Historic District, Fredericktown, 1931
135 West Main, Fredericktown Courthouse Square Historic District, Fredericktown, 1926
417 Logan, (former Arnold and Mills Lumber Yard), Chillicothe Commercial Historic District, Chillicothe
Avenue Theater, Courthouse Square Historic District, West Plains, 1950
Big Pump, Maryville, 1937
Boots Motel, Carthage, 1939
Clay County Courthouse, Liberty, 1936
Daily Express Building, Kirksville, 1936
DeKalb County Courthouse, Maysville, 1939
Dexter Gymnasium, Dexter, 1940
Esquire Theater, Richmond Heights, 1939
Fayette City Park Swimming Pool, Fayette, 1940
Glen Theatre, 1415 South Main Street, Joplin, 1937
Hall of Waters, Excelsior Springs, 1934
Howell County Courthouse, Courthouse Square Historic District, West Plains, 1937
Huffman Auto Sales, Macon
La Plata station, La Plata, 1945
Miller-Star Opera House (now Lewis Street Playhouse), Canton, 1893
Moberly Junior High School, Moberly, 1930
Municipal Auditorium, Moberly, 1939
Plaza Hotel, Trenton, 1930
Renick School, Renick, 1943
Ritz Theatre (now Finke Theatre), California, 1937
Rodgers Theatre Building, Poplar Bluff, 1949
Route Sixty Six Theater (former Newland Hotel), Downtown Webb City Historic District, Webb City, 1891 and 1925
State Theater, Mound City, 1938
Uptown Theatre, Carrollton, 1936
Walt Theatre, New Haven Commercial Historic District, New Haven, 1940
See also
List of Art Deco architecture
List of Art Deco architecture in the United States
References
"Art Deco & Streamline Moderne Buildings." Roadside Architecture.com. Retrieved 2019-01-03.
"Art Deco Buildings in Tulsa". Tulsa Preservation Commission. 2015-05-06. Retrieved 2019-01-03.
"Art Deco Society of Boston, Art Deco Architecture, Art Deco Information". Retrieved 2019-01-03.
Cinema Treasures. Retrieved 2022-09-06
"Court House Lover". Flickr. Retrieved 2022-09-06
"New Deal Map". The Living New Deal. Retrieved 2020-12-25.
"SAH Archipedia". Society of Architectural Historians. Retrieved 2021-11-21.
External links
Art Deco
Lists of buildings and structures in Missouri | List of Art Deco architecture in Missouri | [
"Engineering"
] | 1,067 | [
"Architecture lists",
"Architecture"
] |
71,986,182 | https://en.wikipedia.org/wiki/List%20of%20Art%20Deco%20architecture%20in%20Minnesota | This is a list of buildings that are examples of the Art Deco architectural style in Minnesota, United States.
Ely
Ely City Hall and Fire Department, Ely, 1920s
Ely Community Center, Ely, 1938
Ely State Theater, Ely, 1936
Faribault
Faribault Viaduct, Faribault, 1937
Faribault Water Works, Faribault, 1933–1938
Rice County Courthouse and Jail, Faribault, 1910 and 1934
Thomas Scott Buckham Memorial Library, Faribault, 1930
International Falls
Alexander Baker School, International Falls, 1914
E.W. Backus Junior High School, International Falls, 1936
Pete Peterson Band Shell, International Falls, 1930s
Minneapolis
Aaron and Naomi Friedell House, Minneapolis, 1940
Avalon Theater, Minneapolis, 1924 and 1937
Boulevard Theatre, Minneapolis, 1933
Brede Exhibits-Plus, Minneapolis, 1940s
CenturyLink Building (former Qwest Building), Minneapolis, 1932
Christ Church Lutheran, Minneapolis, 1948
Cream of Wheat Building, Minneapolis, 1928
Dwight C DeMaine, D.D.S. offices, Minneapolis, 1938
Farmers and Mechanics Savings Bank, Minneapolis, 1942
First Avenue, Minneapolis, 1937
Forum Cafeteria, Minneapolis, 1914, 1930
Foshay Tower, Minneapolis, 1929
General Mills Laboratories, Minneapolis, 1930
Hollywood Theater, Minneapolis, 1935
Midtown Exchange, Minneapolis, 1927
Minneapolis Armory, Minneapolis, 1936
Minneapolis Post Office, Minneapolis, 1933
Minnesota Veterans Home, Minneapolis, 1911
Modern Times Cafe (former Modern Dry Cleaner), Minneapolis
Murray's, Minneapolis, 1946
Oak Street Cinema, Minneapolis, 1935
Orpheum Theatre, Minneapolis, 1921
Parkway Theatre, Minneapolis, 1931
Rand Tower, Minneapolis, 1929
Riverview Theater, Minneapolis, 1948
Midtown Exchange, Minneapolis, 1927
Second Church of Christ Scientist, Minneapolis, 1930
Uptown Theater, Minneapolis, 1939
V. M. S. Kaufmann House, Minneapolis, 1936
Washburn Park Water Tower, Minneapolis, 1931
Wells Fargo Center, Minneapolis, 1988
Varsity Theater, Dinkytown, Minneapolis, 1915, 1939
Zinsmaster Apartments (former Zinsmaster Baking Company), Minneapolis
Saint Paul
Como Park Zoo and Conservatory Zoological Building, Saint Paul, 1936
First National Bank Building, Saint Paul, 1915
Grandview Theater, Saint Paul, 1933
Krank Manufacturing Company building, Saint Paul, 1926
Mickey's Diner, Saint Paul, 1937
Minnesota Building, Saint Paul, 1929
Minnesota Milk Company Building, Saint Paul
Robert Street Bridge, Sant Paul, 1926
Roy Wilkins Auditorium, Saint Paul, 1932
Saint Paul City Hall and Ramsey County Courthouse, Saint Paul, 1932
Saint Paul Women's City Club, Saint Paul, 1931
United States Post Office and Customs House, Saint Paul, 1934
Other cities
Alworth Building, Duluth, 1910
Bigfork Village Hall, Bigfork, 1937
Blue Earth Post Building, Blue Earth, 1930s
Brandon Auditorium, City Hall, and Fire Department, Brandon, 1936
Cozy Theatre, Wadena, 1929
David Park House, Bemidji, 1936
Edina Theatre, 3911 West 50th Street, Edina, 1934 and 1981
Grey Eagle Village Hall, Grey Eagle, 1934
Hibbing Disposal Plant, Hibbing, 1939
Hibbing Memorial Building, Hibbing, 1935
Jefferson Elementary School, Winona, 1938
KFAM Radio Station, St. Cloud
Milaca Municipal Hall, Milaca, 1936
Minnesota Music Hall of Fame, New Ulm
Minnesota State Fair 4-H Building, Falcon Heights, 1940
Minnesota State Fair Horticulture Building, Falcon Heights, 1947
Municipal Building – City Hall and Fire Department, Alden, 1938
Naniboujou Club Lodge, East Cook, 1928
NorShor Theatre, Duluth, 1940s
Pastime Arena (now Roller Garden), St. Louis Park, 1930
Plummer Building, Rochester, 1927
Red River History Museum (former school), Shelly
Rialto Theatre, Aitkin, 1937
Roosevelt Hall, Barrett, 1934
United States Post Office, Marshall, 1938
Washington–Kosciusko School, Winona, 1934
Waverly Village Hall, Waverly, 1939
Willmar City Auditorium, Willmar, 1938
Willmar Municipal Airport, Willmar, 1934
Winona City Hall, Winona, 1939
Worthington Band Shell, Worthington, 1941
See also
List of Art Deco architecture
List of Art Deco architecture in the United States
References
"Art Deco & Streamline Moderne Buildings." Roadside Architecture.com. Retrieved 2019-01-03.
Cinema Treasures. Retrieved 2022-09-06
"Court House Lover". Flickr. Retrieved 2022-09-06
"New Deal Map". The Living New Deal. Retrieved 2020-12-25.
"SAH Archipedia". Society of Architectural Historians. Retrieved 2021-11-21.
External links
Art Deco
Lists of buildings and structures in Minnesota | List of Art Deco architecture in Minnesota | [
"Engineering"
] | 946 | [
"Architecture lists",
"Architecture"
] |
71,986,235 | https://en.wikipedia.org/wiki/List%20of%20Art%20Deco%20architecture%20in%20Iowa | This is a list of buildings that are examples of the Art Deco architectural style in Iowa, United States.
Charles City
Charles City School District Building (former Junior High School), Charles City, 1932
Charles Theatre, Charles City, 1936
Floyd County Courthouse, Charles City, 1940
Clinton
Ankeny Building, Clinton, 1931
Farmers Insurance (former National Guard Building), Clinton, 1930s and 1947
NelsoCorp Field, Clinton, 1937
Washington Junior High School and Jefferson Grade School, Clinton, 1935
Davenport
Hotel Blackhawk, Davenport, 1914
Mac's Tavern (former C. A. Fick Building), Davenport, 1934
Mississippi Lofts and Adler Theatre, Davenport, 1931
Monroe Elementary School, Davenport, 1940
United States Courthouse, Davenport, 1933
Des Moines
Argonne Armory, Civic Center Historic District, Des Moines, 1934
AT&T Building (former Northwestern Bell Telephone Company), Des Moines, 1928
Butler House, Des Moines, 1936
Des Moines Art Center, Des Moines, 1948
Des Moines Building, Des Moines, 1930
Des Moines Fire Department Headquarters, Des Moines, 1937
Hotel Kirkwood, Des Moines, 1930
Iowa-Des Moines National Bank Building, Des Moines, 1932
Youngerman Block, Des Moines, 1935
Mason City
Engine House No. 2, Mason City, 1939
Sundell House, Mason City, 1911
United Methodist Church (former First Methodist Church), Mason City, 1951
William C. and Margaret Egloff House, Mason City, 1939
Sioux City
Badgerow Building, Sioux City, 1933
Federal Building and United States Courthouse, Sioux City, 1932
Grandview Park Bandshell, Sioux City, 1935
Leeds Junior High School, Sioux City, 1939
Roberts Stadium, Sioux City, 1933–42
Sioux City Municipal Auditorium, Sioux City, 1938
Warrior Hotel, Sioux City, 1930
Other cities
Allamakee County Courthouse, Waukon, 1940
American Legion Memorial Building, Atlantic, 1939
Audubon County Courthouse, Audubon, 1940
The Avery Theater, Garner, 1931
Bake's Barber Shop, Moville, 1935
Big Slough Creek Bridge, Nichols, 1937
Bremer County Courthouse, Waverly, 1937
Bruce's Snowball Market No. 1 Addition, Perry, 1930
Buchanan County Courthouse, Independence, 1940
Capitol Theater, Burlington, 1937
Cass County Courthouse, Atlantic, 1934
Chariton Masonic Temple, Chariton, 1937
Chickasaw County Courthouse, New Hampton, 1930
City Hall, Lansing, 1938
Clay County National Bank, Spencer, 1920s
Community Building, Hastings, 1937
Decorah Municipal Bathhouse and Swimming Pool, Decorah, 1937
Des Moines County Court House, Burlington, 1940
Estes Park Band Shell, Iowa Falls, 1931
First United Brethren Church, Toledo, 1946
Garner–Hayfield-Ventura Junior High School Auditorium and Gymnasium, Ventura, 1941
Holly Springs Gymnasium and Auditorium, Holly Springs, 1941
Humboldt County Courthouse, Dakota City, 1939
Iowa City Press-Citizen Building, Iowa City, 1937
Iowa Lakes Community College (former Estherville City Hall), Estherville, 1930
Iowa State Bank & Trust Building, Fairfield, 1955
Iowa State Highway Commission District 6 Building, Cedar Rapids
Iowa Theater, Onawa, 1937
Iowa Theater, Winterset
Irwin Consolidated School, Irwin, 1918
Jefferson Elementary School, Creston, 1937
Jones County Courthouse, Anamosa, 1937
Louisa County Courthouse, Wapello, 1928
Malek Theatre, Independence, 1947
Master Service Station, Waterloo, 1930
Masters Building, Mount Pleasant, 1937
New Providence School Gymnasium, New Providence, 1936
Ocheyedan Town Hall, Ocheyedan, 1940
Oleson Park Music Pavilion, Fort Dodge, 1938
Paramount Theatre, Cedar Rapids, 1928
Phenix School Apartments (former West Des Moines Elementary School), West Des Moines, 1939
Pioneer Oil Company Filling Station, Grinnell, 1920s and 1931
Princess Sweet Shop, Iowa Falls, 1935
Reeve Electric Association Plant, Hampton, 1938
Roshek's, Dubuque, 1929
St. Olaf Auditorium, St. Olaf, 1939
Spencer High School and Auditorium, Spencer, 1937
State Savings Bank, Council Bluffs, 1947
Surf Ballroom, Clear Lake, 1933
United States Post Office, Cresco, 1937
United States Post Office, Forest City, 1941
United States Post Office, Mount Ayr, 1939
United States Post Office, Mount Pleasant, 1935
United States Post Office, Onawa, 1937
United States Post Office, Sigourney, 1938
United States Post Office and Courthouse, Dubuque, 1934
Veterans Memorial Elementary School, Reno, 1949
Warren County Courthouse, Indianola, 1939
West Liberty Bridge, West Liberty, 1937
Woodbine Normal and Grade School, Woodbine, 1931
Woodlawn Cemetery Gates and Shelter, Washington, 1917 and 1926
YMCA Building, Waterloo, 1931
See also
List of Art Deco architecture
List of Art Deco architecture in the United States
References
"Art Deco & Streamline Moderne Buildings." Roadside Architecture.com. Retrieved 2019-01-03.
Cinema Treasures. Retrieved 2022-09-06
"Court House Lover". Flickr. Retrieved 2022-09-06
"The Encyclopedia of Arkansas History and Culture". Archived from the original on 2019-01-04. Retrieved 2019-01-04.
"New Deal Map". The Living New Deal. Retrieved 2020-12-25.
"SAH Archipedia". Society of Architectural Historians. Retrieved 2021-11-21.
External links
Art Deco
Lists of buildings and structures in Iowa | List of Art Deco architecture in Iowa | [
"Engineering"
] | 1,085 | [
"Architecture lists",
"Architecture"
] |
71,986,336 | https://en.wikipedia.org/wiki/List%20of%20Art%20Deco%20architecture%20in%20Idaho | This is a list of buildings that are examples of the Art Deco architectural style in Idaho, United States.
Blackfoot
Eastern Idaho State Fair Building, Blackfoot
Nuart Theatre, Blackfoot, 1930
United States Post Office–Blackfoot Main, Blackfoot, 1936
Boise
4531 West Freemont, Boise, 1945
Ada County Courthouse, Boise
Banner Bank Building, Boise, 2007
Baxter Apartment Building, Boise, 1941
Boise Art Museum, Boise, 1937
Boise High School Gymnasium, Boise
Boise Junior High School, Boise, 1937
Boise Municipal Pool, Boise, 1953
The Egyptian Theatre, Boise, 1927
Givens Pursley Building, Boise, 1938
Hitchcock Building, Boise, 1919 and 1930s
Hoff Building, Boise, 1930
Idaho National Guard Armory, Boise, 1931
Idaho Power Building, Boise, 1932
John Regan American Legion Hall, Boise, 1939
Kerhisnik Law Building (former Bruce Budge Medical Building), Boise, 1948
Lowell Elementary, Boise, 1947
Morris Hill Cemetery Mausoleum, Boise, 1937
North Junior High School, Boise, 1937
Reserve Street Armory, Boise, 1931
St. Luke's Hospital, Boise, 1902 and 1928
South Junior High, Boise, 1940s
Sun Ray Cafe, Boise, 1900s and 1950s
Veltex Building, Boise, 2002
Washington Elementary, Boise, 1917 and 1947
Whittier High School, Boise
Idaho Falls
Idaho Falls 5th Ward Meeting House, Idaho Falls, 1939
Idaho Falls Idaho Temple, Idaho Falls, 1937
S. H. Kress and Co. Building, Idaho Falls, 1932
Smith–Hart Building, Idaho Falls
Moscow
Moscow High School, Moscow, 1939
Moscow High School Auditorium, Moscow, 1939
Nuart Theatre, Moscow, 1935
Other cities
Arco City Building, Arco, 1938
Auditorium Theatre, Pocatello, 1900, 1939
Bear Lake Middle School, Montpelier, 1937
Boundary County Courthouse, Bonners Ferry, 1941
Canyon Springs High School, Caldwell, 1941
Cassia County Courthouse, Burley, 1939
City Building and Offices at First and East Center, Pocatello, 1921 and 1940
Consolidated Wagon/Cain's Furniture Building, Twin Falls, 1909 and 1940s
Day Rock Bar (former Liberty Theatre), Wallace, 1929
Depot Sports Bar (former Greyhound Bus Depot), Pocatello, 1946
Franklin County Courthouse, Preston, 1939
Gem County Courthouse, Emmett, 1938
Idaho State University Administration Building, Pocatello, 1939
Jefferson County Courthouse, Rigby, 1938
Jerome County Courthouse, Jerome, 1938
KKOO Radio Station, Weiser, 1947
L. A. Thomas Memorial Gymnasium, Kimberly, 1941
Lewis–Clark State College Gymnasium, Lewiston, 1938
Masonic Hall, Rupert Town Square Historic District, Rupert, 1953
Oneida County Courthouse, Malad City, 1938
Orpheum Theater, Twin Falls, 1921
Owyhee County Courthouse, Murphy, 1936
Parma Grade School, Parma, 1937
Priest River Junior High (former High School), Priest River, 1939–1941
Romance Theater, Rexburg, 1917
Rupert City Hall, Rupert Town Square Historic District, Rupert, 1937
Salmon City Hall and Library, Salmon, 1939
School Gymnasium, Meridian
Smith's Dairy Products (now Cloverleaf Creamery), Buhl, 1940s
Star School Building, Star, 1939
Star Theater, Weiser, 1917 and 1939
Washington County Courthouse, Weiser, 1938
United States Post Office, Buhl, 1939
United States Post Office – Kellogg Main, Kellogg, 1938
United States Post Office – Orofino Main, Orofino, 1940
See also
List of Art Deco architecture
List of Art Deco architecture in the United States
References
"Art Deco & Streamline Moderne Buildings." Roadside Architecture.com. Retrieved 2019-01-03.
Cinema Treasures. Retrieved 2022-09-06
"Court House Lover". Flickr. Retrieved 2022-09-06
"Idaho Architecture Project". Archived from the original on 2018-11-30. Retrieved 2020-02-21.
"New Deal Map". The Living New Deal. Retrieved 2020-12-25.
"SAH Archipedia". Society of Architectural Historians. Retrieved 2021-11-21.
External links
Art Deco
Lists of buildings and structures in Idaho | List of Art Deco architecture in Idaho | [
"Engineering"
] | 830 | [
"Architecture lists",
"Architecture"
] |
64,625,529 | https://en.wikipedia.org/wiki/Click%20tracking | Click tracking is when user click behavior or user navigational behavior is collected in order to derive insights and fingerprint users. Click behavior is commonly tracked using server logs which encompass click paths and clicked URLs (Uniform Resource Locator). This log is often presented in a standard format including information like the hostname, date, and username. However, as technology develops, new software allows for in depth analysis of user click behavior using hypervideo tools. Given that the internet can be considered a risky environment, research strives to understand why users click certain links and not others. Research has also been conducted to explore the user experience of privacy with making user personal identification information individually anonymized and improving how data collection consent forms are written and structured.
Click tracking is relevant in several industries including Human-Computer Interaction (HCI), software engineering, and advertising. Email tracking, link tracking, web analytics, and user research are also related concepts and applications of click tracking. A common utilization of click data from click tracking is to improve results' positions from search engines to make their order more relevant to users' needs. Click tracking employs many modern techniques such as machine learning and data mining.
Tracking and recording technology
Tracking and recording technologies (TRTs) can be split into two categories, institutional TRTs and end-user TRTs. Institutional TRTs and end-user TRTs differ by who is collecting and storing the data, and this can be respectively understood as institutions and users. Examples of TRTs include radio frequency identification (RFID), credit cards, and store video cameras. Research suggests that individuals are concerned with privacy, but they are less concerned with how TRTs are used daily. This discrepancy has been attributed to the public not understanding how information about them is getting collected.
Another means of obtaining user input is eye-tracking or gaze tracking. Gaze-tracking technology is especially beneficial for those with motor disabilities. Systems that employ gaze-tracking often try to mimic cursor and keyboard behavior. In this process, the gaze-tracking system is separated into its own panel in the system interface, and the user experience of this system is compromised as individuals have to switch between the panel and the other interface features. The experience is also difficult because users have to first imagine how to complete the task using keyboard and cursor features and then employ gaze. This causes tasks to take additional time. Hence, researchers created their own web browser called GazeTheWeb (GTW), and the focus of their research was on the user experience. They improved the interface to incorporate gaze better.
Eye-movement tracking is also applied in usability testing when creating web applications. However, in order to track user eye movements, a lab setting with appropriate equipment is often required. Mouse and keyboard activity can be measured remotely, so this quality can be capitalized for usability testing. Algorithms can use mouse movements to predict and trace user eye movements. Such tracking in a remote environment is denoted as a remote logging technique.
Browser fingerprinting is another means of identifying users and tracking them. In this process, information about a user is collected from their web browser to create a browser fingerprint. A browser fingerprint contains information about a device, its operating system, its browser, and its configuration. HTTP headers, JavaScript, and browser plugins can be used to build a fingerprint. Browser fingerprints can change over time from automatic software updates or user browser preference adjustments. Measures to increase privacy in this realm can reduce functionality by blocking features.
Methods of click tracking
User browsing behavior is often tracked using server access logs which contain patterns of clicked URLs, queries, and paths. However, more modern tracking software utilizes JavaScript in order to track cursor behavior. The collected mouse data can be used to create videos, allowing for user behavior to be replayed and easily analyzed. Hypermedia is used to create such visualizations that allow for behavior like highlighting, hesitating, and selecting to be monitored. Technology that is used to record such behavior can also be used to predict it. One of these monitoring tools, SMT2є, collects fifteen cursor features and uses the other fourteen to predict the last feature's outcome. This software also generates a log analysis which summarizes user cursor activity.
In a search session, users can be identified using cookies, identd protocol, or their IP address. This information can then be stored in a database, and every time a user visits a web page again, their click behavior will be appended to the database. DoubleClick Inc. is an example of a company that has such a database and partners with other companies to aid with their web mining. Cookies are added to HTTP (Hypertext Transfer Protocol), and when a user clicks on a link, they are connected to the associated web server. This action of a user clicking on a link is seen as a request, and the server “responds” by sending the user's information, and this information is a cookie. Cookies provide a “bookmark” for users’ sessions on a website, and they store user login information and the pages users visit on a website. This aids with preserving the state of the session. If there is more than one such server, information must be consistent among all servers; hence, information is transferred. Data collected via cookies can be used to improve websites for all users and this also aids with user profiling for advertising.
When data mining techniques and statistical procedures are applied to understand web log data, the process is noted as log analysis or web usage mining. This helps with determining patterns in the users’ navigational behaviors. Some features that can be observed include how long users viewed pages for, click path lengths, and the number of clicks. Web usage mining has three phases. First, the log data is "preprocessed" to see the users and search sessions’ content. Then, tools like association and clustering are applied to look for patterns, and lastly, these patterns are saved to be further analyzed. The tool of association rule mining helps with finding “patterns, associations, and correlations” among pages users visit in a search session. Sequential pattern discovery is association rule mining, but it also accounts for time like the page views in an allotted time period. Classification is a tool that allows for pages to be added to groups representing certain similar qualities.
Some examples of tools individuals can use when conducting click analytics are the Google Analytics tool In-Page Analytics, ClickHeat, and Crazy Egg. These tools create a visual from user click data on a webpage. ClickHeat and Crazy Egg showcase the density of user clicks using specific colors, and all of these tools allow for webpage visitors to be categorized into groups by qualities like being a mobile user or using a particular browser. The specific groups' data can be analyzed for further insight.
Click behaviour
One of the main factors users consider when clicking links is a link's position in a list of results. The closer links are to the top, the more likely they are to be selected by users. When users have a personal connection to a subject matter they tend to click that article more frequently. Pictures, position, and specific individuals in the news content also more heavily influenced users’ decisions. The source of the news was deemed as less important.
Click attitude and click intention play a large role in user click behavior. In one study when research participants were presented with positive and negative insurance advertisement photographs, emotion was seen to have a positive association with click intention and click attitude. The researchers also observed that click attitude affects click intention, and positive emotion has more of an impact than negative emotion on click attitude.
The internet can be considered a risky environment due to the abundance of cybersecurity attacks that can occur and the prevalence of malware. Hence, whenever individuals use the internet, they have to decide whether or not to click on the various links. A 2018 study found that users tend to click on more URLs on websites they are familiar with; this user trait is then exploited by cybercriminals, and personal information can be compromised. Hence, trust is seen to also increase click-through intention. When given Google Chrome warnings, 70% of the time people will click through. They also tend to adjust default computer settings in this process. Users were also found to better recognize malware risks when there is a greater potential for revealing their personal information.
Relevance of search results
Pages that are viewed by users during a particular search session constitute click data. Such data can be used to improve search results in two ways, as explicit and implicit feedback. Explicit feedback is when users indicate which pages are relevant to their search query, while implicit feedback is when user behavior is interpreted to determine results’ relevance. Certain user actions on a webpage that can be used as a part of the interpretation process include bookmarking, saving, or printing a particular web page. Through collecting click data from a few individuals, the relevance of results for all users for given queries can improve. In a search session, a user indicates which documents they are more interested in with their clicks, and this indicates what is relevant to the search. The most relevant click data to determine relevance of results is often the last viewed web page rather than all of the pages clicked on in a search session. Click data outside of search sessions can also be used to improve the accuracy of relevant results for users.
The search results to a given query are usually subject to positional bias. This is because users tend to select links that are at the top of result lists. However, this position does not mean a result is the most relevant since relevance can change over time. As a part of a machine learning approach to improving the result order, human editors begin by supplying an original rank for each result to the algorithm. Then, live user click feedback in the form of tracked click-through rates (CTR) in search sessions can be used to rerank the results based on the data. This improves the order of the results based on the live indicated relevance from the users.
Click dwell time and click sequence information can also be used to improve the relevance of search results. Click dwell time is how long a user takes to return to the search engine results page (SERP) after clicking on a particular result, and this can indicate how satisfied the user is with a particular result. Eye-tracking research indicates that users exhibit an abundance of non-sequential viewing activity when looking at search results. Click models that abide by “top-down” user click behavior cannot interpret the user process of revisiting pages.
Extensions
Advertising
Supply-demand mismatch costs can be reduced through click tracking. Huang et al. defines strategic customers as “forward looking” individuals who know that their clicks are being tracked and expect that companies will engage in appropriate business activities. In the conducted study, researchers used clickstream data from customers to observe their preferences and desired product quantities. Noisy clicks are when customers click but do not actually buy the product. This leads to imperfect advanced demand information or ADI.
Click tracking can be used in the realm of advertising, but there is the potential for this tool to be used negatively. Publishers display advertisements on their websites, and they receive money depending on the amount of traffic, measured as a number of clicks, they send to the advertisers website. Click fraud is when publishers fake clicks to generate revenue for themselves. In the 2012 Fraud Detection in Mobile Advertising (FDMA) conference, competition teams were tasked with having to use data mining and machine learning techniques to determine “fraudulent publishers” from a given dataset. A successful algorithm is able to observe and use morning and night click traffic patterns. When there is density of clicks between these main patterns, it is often an indicator of a fraudulent publisher.
Website content can be adjusted to make it specific to users using “user navigational behavior” and user interests in a process called web personalization. Web personalization is useful in the realm of e-commerce. There are unique steps in the process of web personalization, and the first step is noted as “user profiling.” In this step, the user is understood and constituted through their click behavior, preferences, and qualities. Following user profiling is “log analysis and web usage mining.”
Email
Phishing is usually administered through emails, and when a user clicks on a phishing attempt email, their information will be leaked to particular websites. Spear-phishing is a more “targeted” form of phishing in which user information is used to personalize emails and entice users to click. Some phishing emails will also contain other links and attachments. Once these are either clicked or downloaded, users’ privacy can be encroached. Lin et al. conducted a study to see which psychological “weapons of influence” and “life domains” affect users most in phishing attempts, and they found that scarcity was the most influential factor weapon of influence, and the legal domain was the most influential life domain. Age is also an important factor in determining those who are more susceptible to clicking on phishing attempts.
When a virus infects a computer, it finds email addresses and sends copies of itself through these emails. These emails will usually contain an attachment and will be sent to several individuals. This differs from user email account behavior because users tend to have a particular network they communicate with regularly. Researchers studied how the Email Mining Toolkit (EMT) could be used to detect viruses by studying such user email account behavior and found that it was easier to decipher quick, broad viral propagations in comparison to slow, gradual viral propagations.
In order to know what emails users have opened, email senders engage in email tracking. By merely opening an email, users' email addresses can be leaked to third parties, and if users click on links within the emails, their email address can get leaked to a larger number of third parties. Also, each time a user opens an email sent to them, their information can get sent to a new third party among those that their address has already been leaked to. Many third party email trackers are also involved in web tracking, leading to further user profiling.
Privacy
Privacy-protection models anonymize data after it is sent to a server and stored in a database. Hence, user personal identification information is still collected, and this collection process is based on users trusting such servers. Researchers study giving users control over what information is sent from their mobile devices. They also observe giving users control over how that information is represented in databases in the realm of trajectory data, and they create a system that allows for this approach. This approach gives users the potential to increase their privacy.
When user privacy is going to be encroached, consent forms are often distributed. The type of user activity required in these forms can have an effect on how much information a user retains from the form. Karegar et al. compares the simple agree/disagree format with forms that incorporate checkboxes, drag and drop (DAD), and swipe features. When testing what information users would agree to disclose with each of the consent form formats, researchers observed that users presented with DAD forms had a greater number of eye-fixations and on the given consent form.
When a third-party is associated with a first-party website or mobile application, anytime a user visits the first party website or mobile application, their information will be sent to the third-party. Third-party tracking generates more privacy concerns than first-party tracking because it allows for many website or application records about a particular user to be combined, yielding better user profiles. Binns et al. found that among 5000 popular websites, the top two websites alone had 2000 trackers. Of the 2000 embedded trackers, 253 were used in 25 other websites. Researchers evaluated the reach of third-party trackers based on their contact with users rather than websites, so more "popular" trackers were those who received information about the highest number of people rather than code embedded in the most first-parties. Google and Facebook were deemed as the first and second largest web trackers, and Google and Twitter were deemed as the first and second largest mobile trackers.
See also
Click path
Click analytics
Web analytics
Phishing
Web log analysis software
Web mining
Search session
References
Web analytics | Click tracking | [
"Technology"
] | 3,326 | [
"Tracking",
"Wireless locating"
] |
64,625,567 | https://en.wikipedia.org/wiki/Sunspot%20drawing | Sunspot drawing or sunspot sketching is the act of drawing sunspots. Sunspots are darker spots on the Sun's photosphere. Their prediction is very important for radio communication because they are strongly associated with solar activity, which can seriously damage radio equipment.
History
Sunspots were probably first drawn by an English monk John of Worcester on 8 December 1128. There are records of observing sunspots from 28 BC, but that is the first known drawing of sunspots, almost 500 years before the telescope. His drawing seems to come around solar maximum. Five days later, the Korean astronomer saw the northern lights above his country, so this is also the first prediction of coronal mass ejection.
In 1612, Galileo Galilei was writing letters on sunspots to Mark Welser. They were published in 1613. In his telescope, he saw some darker spots on Sun's surface. It seems like he was observing the Sun and drawing sunspots without any filter, which is very hard. He said, "The spots seen at sunset are observed to change the place from one evening to the next, descending from the part of the sun then uppermost, and the morning spots ascend from the part then below ...". From there it seems that he observed the Sun at sunset, but not at sunrise because of the high horizon of Apennines. It is also possible, that he was referring to Scheiner's observation, where he first saw that the Sun is rotating. He complained that he couldn't observe the Sun every morning and evening because of low clouds and so he couldn't see their motion with confidence. He Probably never observed them in the middle of the day. In the same year, his student Benedetto Castelli invented a new method for observing and drawing sunspots, the projection method. Probably, he was never looking at the Sun directly through the telescope.
The Mount Wilson observatory started drawing sunspots by hand in 1917. This tradition continues still today. The early drawers did not draw their shapes and positions very accurately because they wanted just to mark where the sunspots were on the magnetic data. However, in modern times, the drawers became very accurate and sunspot drawing became art; sometimes they needed many hours to complete work. On the white acid-free paper, they draw a circle with solar coordinates and draw and mark sunspots.
Today
With a pinhole and a screen one can produce an image of the Sun. But for better viewings of the sunspots one needs a telescope with 8 inches of diameter or more. There are two ways of drawing sunspots: projection and direct viewing.
Projection on the screen
The easiest way to draw sunspots is to project the image of the Sun to the screen. The further the screen, the bigger the image, but also less bright, so one has to find the perfect proportion. For 10 inch telescope, the optimal distance of the screen from the eyepiece is 1–1.5 meter.
When the Sun is projected, there are two ways for drawing sunspots: you can project Sun on the screen, look at it and draw sunspots on the table, but you can also project the Sun on the drawing paper, just mark the position and draw the shape.
Direct viewing
One less accurate way to do this is to buy the special filter for blocking the light from the Sun. One can look directly in the telescope in that case and draw the sunspots whilst looking at them.
References
External links
Daily image of the Sun and number of the sunspots
Daily illustration of the Sun at Mount Wilson observatory
Technical drawing | Sunspot drawing | [
"Engineering"
] | 750 | [
"Design engineering",
"Technical drawing",
"Civil engineering"
] |
64,626,807 | https://en.wikipedia.org/wiki/Pan-Canadian%20Framework%20on%20Clean%20Growth%20and%20Climate%20Change | The Pan-Canadian Framework on Clean Growth and Climate Change (PCFCGCC or PCF; French: Cadre pancanadien sur la croissance propre et les changements climatiques, CPCPCC or CPC), Canada's national climate strategy, was released in August 2017 by the Government of Canada. Provincial premiers (except Saskatchewan and Manitoba) adopted the PCF on December 9, 2016.
Background
According to a London School of Economics (LSE) December 2016 paper, "The Pan-Canadian Framework on Clean Growth and Climate Change (PCFCGCC)" provided an extensive description of "executive, mitigation and adaptation" strategies for a clean economy. that "lean[-ed] heavily on carbon pricing". The Canadian federal government's Pan-Canadian Framework on Clean Growth and Climate Change and promoted sustainable building programs.
The PCFCGCC's four main interrelated pillars are ""carbon pollution pricing", "complementary actions to reduce emissions", "adaptation and resilience", and "clean technology, innovation and jobs". The document also includes sections on "reporting and oversight" and "federal engagement and partnership with Indigenous Peoples."
Carbon pollution pricing
Carbon pricing is a major keystone component of the Pan-Canadian Framework, which relies on existing provincial carbon pricing systems and a federal backstop to ensure that equivalent levels of carbon pricing apply across Canada.
Adaptation and resilience
BRACE
"Building Regional Adaptation Capacity and Expertise (BRACE) is a program that is increasing the ability of communities, organizations, small and medium-sized enterprises and practitioners to access, use, and apply knowledge and tools on climate change adaptation in their work."
Clean technology, innovation and jobs
Zero-energy building
Canada's Buildings Strategy, Build Smart, that focuses on increasing energy efficiency in buildings in pursuit of eventually attaining zero-energy buildings, is another key driver of Pan-Canadian Framework on Clean Growth and Climate Change.
The federal government represented by Natural Resources Canada, the provinces and territories endorsed Build Smart: Canada's Buildings Strategy in December 2017. The Build Smart strategy commits those who sign the agreement to a "net-zero energy ready" model building code by 2030 and to development and adoption of stringent model building codes starting in 2020.
In August 2017, British Columbia joined Canada's federal government, represented by Natural Resources Canada, and other provinces and territories in endorsing the Build Smart: Canada's Buildings Strategy. The strategy commits signatories to develop and adopt increasingly stringent model building codes, starting in 2020, with the goal that provinces and territories adopt a "net-zero energy ready" model building code by 2030. In British Columbia, the BC Energy Step Code serves as a technical policy pathway for British Columbia to deliver on that goal.
Fugitive gas emissions
The Framework includes plans that would reduce oil and gas sector emissions by 2025 to 40% below 2012 levels.
Nunavut
According to a November 2017 article in the journal Climatic Change, the federal government placed "increased emphasis" on climate change as evident in the 2016 Pan-Canadian Framework on Clean Growth and Climate Change. While Nunavut had already made notable progress around in regards to "adaptation planning", which included examples of "adaptation champions", "pressing socio-economic problems", along with "institutional and governmental barriers", have impeded implementation of adaptation. The authors of the article noted that, at the federal level, "there is evidence of high-level leadership on adaptation, the creation of adaptation programs, and allocation of funds for adaptation." The focus they said "has been mostly on researching adaptation options as opposed to supporting actual actions or policy change." The authors recommended that the Government of Nunavut implement "legislative and regulatory requirements for adaptation" to increase "emphasis on adaptation". The Government of Nunavut created a "strategic planning document on adaptation—Upagiaqtavut, which is "mainstreamed for decision making across departments". According to the article, the role of the federal government with its "complex, multilevel political systems" under Canadian federalism, of "supporting provinces and territories on adaptation" which is outlined in the Pan-Canadian Framework, includes "providing information, coordination, and facilitation to draw attention to adaptation, engage public and private actors, and build support for policy objectives." The Pan-Canadian Framework is a federal commitment to collaborate with "communities and governments to create a Northern Adaptation Strategy for Canada’s Arctic territories."
See also
Climate change in Canada
Technological Innovation for Climate Change Mitigation
BC Energy Step Code
Energy policy of Canada
Efficient energy use
Passive house
California Green Building Standards Code
References
External links
Climate change in Canada
Building codes
Standards of Canada | Pan-Canadian Framework on Clean Growth and Climate Change | [
"Engineering"
] | 966 | [
"Building engineering",
"Building codes"
] |
64,628,311 | https://en.wikipedia.org/wiki/Allene%20Johnson | Allene Johnson (born April 20, 1933) is a retired chemical educator who taught in the Summit, New Jersey school system for over 40 years.
Background and career
Johnson was one of six children and grew up in the segregated American South. She attended Brunswick County, North Carolina High School and graduated from North Carolina Central University in 1954 with her B.S. degree in Chemistry. According to the book African American Women Chemists, she "..bought her chemicals and equipment from the drug store" to improvise labs for her first position as a high school teacher in Shallotte, North Carolina. She later moved to New Jersey, after a Master's degree program at Ohio State University, in 1963, where she taught in the Summit system until retiring in 1997.
Championing diversity
The Delta Sigma Theta sorority founded the Delta Academy for maths and science, and Johnson volunteers with the New Jersey chapter which focuses on minority middle-school girls. She conducts “Chemistry for Kids” workshops to enhance the education on minority students. Johnson is also a member of the American Chemical Society Project SEED committee, where she visits schools to encourage minority students to participate in Project SEED. Johnson also provides workshops and training for minority teachers in the Newark school district. Johnson served as a judge for several science awards, notably the 2003 Chemagination awards, and has served as an educational advisor for the New Jersey ACS section for many years.
Awards and honors
2006 - American Chemical Society Stanley Israel Award for increasing Diversity in the Chemical Sciences
2005 - ChemLuminary Award
2005 - Citation Scroll, NJSTA
1977 - Fellow of the New Jersey Science Teacher's Association
Presidential Award in Science & Mathematics Teaching
Honored with a named chemistry scholarship at Summit High School (New Jersey)
References
1933 births
Living people
North Carolina Central University alumni
Ohio State University College of Education and Human Ecology alumni
American Chemical Society
Scientists from North Carolina
21st-century African-American educators
21st-century American educators
20th-century American scientists
21st-century American scientists
20th-century African-American scientists
21st-century African-American scientists
Chemists from North Carolina
Chemists from New Jersey | Allene Johnson | [
"Chemistry"
] | 426 | [
"American Chemical Society"
] |
64,631,644 | https://en.wikipedia.org/wiki/Warren%20B.%20Mori | Warren Bicknell Mori (born August 8, 1959) is an American computational plasma physicist and a professor at the University of California, Los Angeles. He was awarded the 2020 James Clerk Maxwell Prize for Plasma Physics for his contributions to the theory and computer simulations of non-linear processes in plasma-based acceleration using kinetic theory, as well as for his research in relativistically intense lasers and beam-plasma interactions.
Early life and career
Mori received a Bachelor of Science from the University of California, Berkeley in 1981. He then went to the University of California, Los Angeles (UCLA) and obtained a Master of Science and a Doctor of Philosophy (Ph.D.) in 1984 and 1987 respectively. For his Ph.D. in electrical engineering, Mori was supervised by plasma physicists Francis F. Chen, John M. Dawson and Chandrashekhar J. Joshi, all of whom were noted for winning the James Clerk Maxwell Prize for Plasma Physics. Mori then remained at UCLA, and has been there ever since.
Mori was a director of UCLA's Institute for Digital Research and Education. He is currently a director of UCLA's Particle-in-Cell and Kinetic Simulation Software Center and Plasma Simulation Group.
Honors and awards
Mori is a fellow of the American Physical Society and the Institute of Electrical and Electronics Engineers.
In 1995, Mori received the International Center for Theoretical Physics Medal for Excellence in Nonlinear Plasma Physics by a Young Researcher. He also won the 2016 Advanced Accelerator Concepts Prize of the Lawrence Berkeley National Laboratory for "his leadership and pioneering contributions in theory and particle-in-cell code simulations of plasma based particle acceleration".
Mori was awarded the 2020 James Clerk Maxwell Prize for Plasma Physics for "leadership in and pioneering contributions to the theory and kinetic simulations of nonlinear processes in plasma-based acceleration, and relativistically intense laser and beam plasma interactions".
References
Living people
1959 births
21st-century American physicists
American plasma physicists
Computational physicists
Fellows of the IEEE
Fellows of the American Physical Society
University of California, Berkeley alumni
University of California, Los Angeles alumni | Warren B. Mori | [
"Physics"
] | 417 | [
"Computational physicists",
"Computational physics"
] |
64,631,865 | https://en.wikipedia.org/wiki/A%20Science%20on%20the%20Scales | A Science on the Scales: The Rise of Canadian Atlantic Fisheries Biology, 1898-1939 is a 2011 book by Jennifer Hubbard. The book provides an analysis of Canadian fisheries history with the tools of the professional historian, when most earlier works on the topic came from fisheries scientists themselves.
The book traces the development of fisheries science in Canada in the first decades of the twentieth century. Fisheries biology arose in the mid-1800s in Northern Europe from concerns around the conservation of what appeared to be dwindling stocks in the face of new technology. Marine biological stations were established in Europe in the last decades of the nineteenth century—particularly in Naples (the Stazione Zoologica Anton Dohrn) and Plymouth—but the Canadian Department of Marine and Fisheries, established in 1892, did not see a need for one in Canada, though a floating station on board a scow was eventually set up.
The book "surveys the tortuous process by which the Biological Board of Canada was established in 1912 to supersede a board of management that had overseen a floating biological station off the Atlantic coast since 1898, and permanent stations at St. Andrews, New Brunswick, and Nanaimo, British Columbia, since 1908." Norwegian zoologist Johan Hjort and American ichthyologist David Starr Jordan were both consulted on Canadian fisheries issues in the early period.
The Biological Board eventually became the Fisheries Research Board, but Hubbard explains that "its activities [were] perennially challenged and eventually usurped by federal departments" while constantly hampered by conflicting priorities among its federal funders and the academic biologists who volunteered as its staff. The book also explores the conflicts between the academic knowledge of biologists and the local and craft knowledge of fishers.
While the main focus of the book—the establishment of the structural components of Canadian fisheries biology—ends around 1940, its importance comes in part from its explication of the historical structure of Canadian fisheries science just a decade after the catastrophic collapse of the Atlantic northwest cod fishery in the 1990s, which the book engages in an extended epilogue. The book's explanation of "the complex tensions that result when a problem places science, business, government, and environment at potential cross-purposes" thus provide useful background for understanding the collapse.
In its analysis of the background of collapse, the book is part of a growing effort in the early twenty-first century to historicize the ocean, and particularly fisheries, following marine biologist Daniel Pauly's identification of the "shifting baseline" concept in the measurement of fish populations over time.
See also
All the Fish in the Sea: Maximum Sustainable Yield and the Failure of Fisheries Management by Carmel Finley
References
2006 non-fiction books
Environmental non-fiction books
Maritime history
History of science and technology
History books about Canada
Environmental history of Canada
Canadian non-fiction books | A Science on the Scales | [
"Technology"
] | 564 | [
"History of science and technology"
] |
64,632,429 | https://en.wikipedia.org/wiki/Conceptual%20question | Conceptual questions or conceptual problems in science, technology, engineering, and mathematics (STEM) education are questions that can be answered based only on the knowledge of relevant concepts, rather than performing extensive calculations. They contrast with most homework and exam problems in science and engineering that typically require plugging in numerical values into previously discussed formulas. Such "plug-and-chug" numerical problems can often be solved correctly by just matching the pattern of the problem to a previously discussed problem and changing the numerical inputs, which requires significant amounts of time to perform the calculations but does not test or deepen the understanding of how the concepts and formulas should work together. Conceptual questions, therefore, provide a good complement to conventional numerical problems because they need minimal or no calculations and instead encourage the students to engage more deeply with the underlying concepts and how they relate to formulas.
Conceptual problems are often formulated as multiple-choice questions, making them easy to use during in-class discussions, particularly when utilizing active learning, peer instruction, and audience response. An example of a conceptual question in undergraduate thermodynamics is provided below:
During adiabatic expansion of an ideal gas, its temperatureincreases
decreases
stays the same
Impossible to tell/need more information
The use of conceptual questions in physics was popularized by Eric Mazur, particularly in the form of multiple-choice tests that he called ConcepTests. In recent years, multiple websites that maintain lists of conceptual questions have been created by instructors for various disciplines. Some books on physics provide many examples of conceptual questions as well.
Multiple conceptual questions can be assembled into a concept inventory to test the working knowledge of students at the beginning of a course or to track the improvement in conceptual understanding throughout the course.
References
Science education
Technology education
Engineering education
Mathematics education
Educational evaluation methods | Conceptual question | [
"Technology"
] | 361 | [
"nan"
] |
64,634,201 | https://en.wikipedia.org/wiki/BioTech%20Foods | BioTech Foods is a Spanish biotechnology company dedicated to the development of cultured meat from the cultivation of muscle cells previously extracted from animals. It is a subsidiary of Brazilian company JBS S.A.
History
Origins
The company is based in Donostia–San Sebastián, Basque Country and was co-founded in 2017 by the CTO of the project, Mercedes Vila, and CEO Iñigo Charola.
This project is based on the construction of tissues from the natural proliferation of animal cells in a controlled environment of humidity and temperature, without genetic modification or antibiotics. Cultured meat based on tissue engineering aims to help alleviate three serious sustainability problems: the high increase in global demand for animal proteins, the environmental impact of factory farming, associated with the production of greenhouse gases and deforestation and animal welfare.
Development
The start-up obtained the support of the CIC Nanogune, a research centre promoted by the Basque government. In 2019 BioTech Foods received the Entrepreneur XXI Award and came first in Expansión's Start Up awards in the Food and Agrotech category.
By February 2020, BioTech Foods was in the development phase of Ethicameat, its brand of pig protein products for the general public and the meat sector. BioTech Foods was one of the first companies to emerge in the global cultured meat sector which could help increase food safety and prevent zoonotic diseases.
Pilot plant and JBS investment
As of July 2019, one of the main challenges of the cultivated meat was the high production costs of products. BioTech Foods stated it sought 'to reach pilot scale by 2021'. By the end of 2019, BioTech had opened its first pilot plant.
In November 2021, BioTech Foods announced an agreement by which JBS S.A. was going to acquire a majority of shares in the company, including the pilot plant it operated in San Sebastián. JBS was going to invest in the construction of a new production plant to help BioTech achieve commercial production capacity in mid-2024.
References
External links
Cellular agriculture
Food technology organizations
Biotechnology companies of Spain
Tissue engineering
Spanish companies established in 2017
Spanish subsidiaries of foreign companies
JBS S.A. subsidiaries | BioTech Foods | [
"Chemistry",
"Engineering",
"Biology"
] | 437 | [
"Biological engineering",
"Cloning",
"Chemical engineering",
"Tissue engineering",
"Medical technology"
] |
64,634,404 | https://en.wikipedia.org/wiki/Protein%20Engineering%20Design%20%26%20Selection | Protein Engineering Design & Selection is a publication of Oxford University Press. Created in 1986, the Journal covers topics related the engineering, design and selection of proteins for use in biotechnology and therapy, and for understanding the fundamental link between protein sequence, structure, dynamics, function, and evolution.
Abstracting and indexing
Protein Engineering Design & Selection is indexed in Biological Abstracts, BIOSIS Previews, Biotechnology and Bioengineering Abstracts, Biotechnology Citation Index, CAB Abstracts, Chemical Abstracts, Current Contents, EMBASE, Environmental Science and Pollution Management, Food Science and Technology Abstracts, Journal Citation Reports, ProQuest, and Science Citation Index. According to the latest Journal Citation Reports, the journal has a 2019 impact factor of 1.774, ranking it 247th out of 297 in the category "Biochemistry & Molecular Biology" and 120th out of 156 in the category "Biotechnology & Applied Microbiology".
References
External links
Journal homepage
Submission website
Oxford University Press
Molecular and cellular biology journals
Hybrid open access journals
Academic journals established in 1980
Oxford University Press academic journals
Monthly journals | Protein Engineering Design & Selection | [
"Chemistry"
] | 213 | [
"Molecular and cellular biology journals",
"Molecular biology"
] |
64,635,007 | https://en.wikipedia.org/wiki/Toxicology%20Research | Toxicology Research is a publication of Oxford University Press as of 2020. The Journal launched in 2012 and focuses on articles that cover biological, chemical, clinical, or environmental health aspects of the toxic response and the mechanisms involved.
Abstracting and Indexing
Toxicology Research is abstracted and indexed in Biological Abstracts, BIOSIS Previews, EBSCOhost, Current Contents, Embase, Journal Citation Reports, ProQuest, PubMed, Science Citation Index, Scopus, and Web of Science. According to the latest Journal Citation Reports, the journal has a 2019 impact factor of 2.283, ranking it 64th out of 92 journals in the category "Toxicology".
References
External links
Journal homepage
Submission website
Toxicology journals
Hybrid open access journals
Oxford University Press academic journals
Academic journals established in 2012
Bimonthly journals
Toxicology in the United Kingdom | Toxicology Research | [
"Environmental_science"
] | 173 | [
"Toxicology in the United Kingdom",
"Toxicology",
"Toxicology journals"
] |
64,635,072 | https://en.wikipedia.org/wiki/Sexual%20segregation%20%28biology%29 | In biology, sexual segregation is the differential use of space, habitats, and resources by males and females, or the separation of males and females into different social groups outside the breeding season. Sexual segregation is widespread among animals, especially among vertebrates that live in groups, and has also been observed in plants. It was first formally proposed by Charles Darwin in his book The Descent of Man, and Selection in Relation to Sex.
Definition
Sexual segregation has traditionally been defined as the differential use of space (spatial segregation) or habitat (habitat segregation) by males and females. Recently, it has also been defined as the separation of males and females into different social groups (social segregation) outside the breeding season. Some authors consider social segregation to be a by-product of habitat segregation but it is now known that social segregation can occur independently of habitat segregation. Conradt (2005) argued that spatial segregation should be treated as a auxiliary concept as both habitat segregation and social segregation can lead to spatial segregation.
References
Ecology
Ethology | Sexual segregation (biology) | [
"Biology"
] | 205 | [
"Behavioural sciences",
"Ethology",
"Behavior",
"Ecology"
] |
64,635,161 | https://en.wikipedia.org/wiki/High-frequency%20oscillations | High-frequency oscillations (HFO) are brain waves of the frequency faster than ~80 Hz, generated by neuronal cell population. High-frequency oscillations can be recorded during an electroencephalagram (EEG), local field potential (LFP) or electrocorticogram (ECoG) electrophysiology recordings. They are present in physiological state during sharp waves and ripples - oscillatory patterns involved in memory consolidation processes. HFOs are associated with pathophysiology of the brain like epileptic seizure and are often recorded during seizure onset. It makes a promising biomarker for the identification of the epileptogenic zone. Other studies points to the HFO role in psychiatric disorders and possible implications to psychotic episodes in schizophrenia.
Background and history
Traditional classification of the frequency bands, that are associated to different functions/states of the brain and consist of delta, theta, alpha, beta and gamma bands. Due to the limited capabilities of the early experimental/medical setup to record fast frequencies, for historical reason, all oscillations above 30 Hz were considered as high frequency and were difficult to investigate. Recent advance in manufacturing electrophysiological setups enables to record electric potential with high temporal and space resolution, and to "catch" dynamics of single cell action potential. In neuroscience nomenclature, there is still a reaming gap between ~100 Hz and multi unit activity (>500 Hz), so these oscillations are often called high gamma or HFO.
Neurophysiological features
HFO are generated by different cellular mechanisms and can be detected in many brain areas. In hippocampus, this fast neuronal activity is effect of the population synchronous spiking of pyramidal cells in the CA3 region and dendritic layer of the CA1, which give rise to a characteristic oscillation pattern (see more in sharp waves and ripples). The HFO occurrence during memory task (encoding and recalling images) was also reported in human patients from intracranial recordings in primary visual, limbic and higher order cortical areas. Another example of physiological HFO of around 300 Hz, was found in subthalamic nucleus, the brain region which is the main target for high-frequency (130 Hz) deep brain stimulation treatment for patients with Parkinson's disease.
Somatosensory evoked high-frequency oscillations
ECoG recordings from human somatosensory cortex, has shown HFO (reaching even 600 Hz) presence during sensory evoked potentials and somatosensory evoked magnetic field after median nerve stimulation. These bursts of activity are generated by thalamocortical loop and driven by highly synchronized spiking of the thalamocortical fibres, and are thought to play a role in information processing. Somatosensory evoked HFO amplitude changes may be potentially used as biomarker for neurologic disorders, which can help in diagnosis in certain clinical contexts. Some oncology patients with brain tumors showed higher HFOs amplitude on the same side, where the tumor was. Authors of this study also suggest contribution from the thalamocortical pathways to the fast oscillations. Interestingly, higher HFO amplitudes (between 400 and 800 Hz) after nerve stimulation were also reported in the EEG signal of healthy football and racquet sports players.
Pathological HFO
There are many studies, that reports pathophysiological types of HFO in human patients and animal models of disease, which are related to different psychiatric or neurological disorders:
Amplitude aberrations of the sensory evoked HFOs (600 Hz) was reported in mild demyelination in multiple sclerosis patients.
HFO (>80 Hz) occur during epileptic seizure onset.
Disruption in the HFO (200–500 Hz) synchronization in subthalamic nucleus is related to Parkinson's disease symptoms.
HFOs are visible in different brain regions just after cardiac-arrest and are linked to near-death states.
High amplitude HFOs (80–200 Hz) bursts correlates with psychotic-like state evoked with PCP or subanesthetic dose of ketamine (and other NMDA receptor blockers).
NMDA receptor hypofunction HFO
There are increasing number of studies indicating that HFO rhythms (130–180 Hz) may arise due to the local NMDA receptor blockage, which is also a pharmacological model of schizophrenia. These NMDA receptor dependent fast oscillations were detected in different brain areas including hippocampus, nucleus accumbens and prefrontal cortex regions. Despite the fact that this type of HFO was not yet confirmed in human patients, second generation antipsychotic drugs, widely used to treat schizophrenia and schizoaffective disorders (i.e. Clozapine, Risperidone), were shown to reduce HFO frequency. Recent studies, reports on the new source of HFO in the olfactory bulb structures, which is surprisingly stronger than any other previously seen in the mammalian brain. HFO in the bulb is generated by local excitatory-inhibitory circuits modulated by breathing rhythm and may be also recorded under ketamine-xylazine anesthesia. This findings may aid understanding early symptoms of schizophrenia patients and their relatives, that can suffer from olfactory system impairments.
See also
Brain waves
Delta wave – (0.1 – 3 Hz)
Theta wave – (4 – 7 Hz)
Mu wave – (7.5 – 12.5 Hz)
SMR wave – (12.5 – 15.5 Hz)
Alpha wave – (7 (or 8) – 12 Hz)
Beta wave – (12 – 30 Hz)
Gamma wave – (32 – 100 Hz)
References
Neuroscience
Neural coding
Neural circuitry
Neurophysiology
Electrophysiology
Computational neuroscience | High-frequency oscillations | [
"Biology"
] | 1,228 | [
"Neuroscience"
] |
64,635,593 | https://en.wikipedia.org/wiki/YSES%201 | YSES 1, also known as TYC 8998-760-1, is a young star, about old, located 310 light years away in the constellation of Musca, with a mass times the Sun.
Planetary system
There are two giant bodies orbiting the star. The European Southern Observatory's Very Large Telescope photographed the two bodies using its SPHERE instrument, producing the first direct image of multiple bodies orbiting a Sun-like star.
TYC 8998-760-1 b
TYC 8998-760-1 b is a body which has a mass 21.8 times that of Jupiter (most likely making it a brown dwarf), and a radius of . It orbits at a distance of , or slightly more than 5 times the Neptune-Sun distance. In July 2021, astronomers reported the detection, for the first time, of an isotope in the atmosphere of an exoplanet; more specifically, the isotope Carbon-13 (C13) was found in the atmosphere. This was later confirmed with VLT/CRIRES+. This spectrum showed that the atmosphere is dominated by water vapor and carbon monoxide. The researchers also detect hydrogen fluoride in the atmosphere. The object is an L-dwarf with a spectral type of L0.
TYC 8998-760-1 c
TYC 8998-760-1 c is a body with a mass of , and orbits at , or slightly more than 11 times the Neptune-Sun distance. Atmospheric water vapor and carbon monoxide was detected with VLT/CRIRES+. The object is an L-dwarf with a spectral type of L7.5. Additionally JWST spectra with NIRSpec and MIRI will be published in the future. The spectrum of TYC 8998-760-1 c does show direct detection of silicate clouds.
References
Planetary systems with two confirmed planets
Musca
K-type main-sequence stars
TIC objects
2MASS objects | YSES 1 | [
"Astronomy"
] | 404 | [
"Musca",
"Constellations"
] |
64,636,692 | https://en.wikipedia.org/wiki/HAT-P-36 | HAT-P-36, also referred to as Tuiren is a 12th magnitude G-type main-sequence star estimated to be approximately 958 light-years away from Earth in the constellation Canes Venatici. HAT-P-36 is too faint to be seen with the naked eye, but it is possible to view it with binoculars or a small telescope. In 2012 a hot Jupiter-type exoplanet was discovered orbiting HAT-P-36 with an orbital period of about 1.3 Earth days. In December 2019, HAT-P-36 was named Tuiren and its planetary companion, HAT-P-36b, was named Bran as a result of Ireland's contribution to the 2019 NameExoWorlds campaign. Bran has a mass approximately 1.8 times that of Jupiter and a radius 1.2 times larger.
Etymology
HAT-P-36 and its planet are named after characters from The Birth of Bran, a story in the book Irish Fairy Tales by James Stephens. The book is a re-telling of various stories from Irish folklore. Tuiren was the aunt of the mythical hero Fionn mac Cumhaill and was turned into a hound by the fairy Uchtdealbh after Tuiren married her husband. Bran and Sceólan were the two puppies mothered by Tuiren while she was a dog. They were cousins of Fionn mac Cumhaill. The names were proposed by John Murphy, a teacher at Regina Mundi College, Cork.
Planets
HAT-P-36b (Bran) was discovered in 2012 by the HATNet Project using the transit method. A search for transit timing variation did not result in detection of additional planets in the system as at 2021. Surprisingly, a planetary orbital period increase by 0.014 seconds per year was detected by 2021.
References
G-type main-sequence stars
Canes Venatici
Stars with proper names
Planetary systems with one confirmed planet
Planetary transit variables | HAT-P-36 | [
"Astronomy"
] | 404 | [
"Canes Venatici",
"Constellations"
] |
64,637,325 | https://en.wikipedia.org/wiki/Early%20contractor%20involvement | Early contractor involvement (ECI) is a type of construction contract where the principal contractor is engaged at an early stage in a project to offer input into the design phase. It is in contrast to the design–bid–build model where the contractor is only brought onboard at the end of the design phase. The model allows the contractor to have an input in the design of the scheme and suggest value engineering changes. Studies have shown that savings of around 10% in construction phase time and 7% in cost are achievable through the use of ECI. The ECI model has become increasingly popular in the United Kingdom since the early 2000s and is also used in Australia and New Zealand.
Description
In traditional construction contracts (known as design–bid–build contracts) the principal contractor is only engaged when a detailed design is complete. An invitation to tender is published and a number of contractors will price the construction of the design, from which a single winner will be chosen to complete the works. Contractors are traditionally not paid for their work on the tender and only the winning contractor, therefore, has the opportunity to recover costs through his profit margin on the construction work. As unsuccessful tenderers may incur substantial costs in pricing complicated works this tended to lead to inflated prices.
Under an early contractor involvement (ECI) system a single contractor is selected at an earlier stage in the process and is paid for their work on the scheme. This can be either at the preliminary/concept design or detailed design stages, depending on client preference. The contractor can then use their knowledge and experience to influence the project design to increase buildability or value and may be asked to advise on construction phase risks. The contractor may choose to involve their supply chain sub-contractors in the process to offer additional expertise. The contractor is able to build their price for the works during the process, in consultation with the client and designer.
As the ability of parties to affect project cost and programme is greater in the design stages than in the construction phase then the potential for value engineering is greater under ECI contracts than traditional contracts. ECI contracts tend to lead to more harmonious client-contractor relationship, though there is less competition than with traditional open tenders. The ECI contract model has similar aims to the design–build model, but responsibility for the design is retained with the design team.
History
The model was first studied in 1976 and studies through the 1990s showed that adopting such a model could generate 10% savings on project time and 7% on cost. The wider adoption of ECI was a recommendation of the 1994 Latham Report into systemic failings in the British construction industry; the practice became increasing popular during the early 2000s. Initially ECI work tended to be unpaid but this proved unsatisfactory to contractors who thought it devalued their contributions and by 2005 most ECI work was on a paid basis. This also helped to prevent losses to contractors in instances when projects did not progress to construction, under unpaid ECI contracts clients had faced claims for compensation from contractors in these cases.
An ECI option was introduced into the popular NEC Engineering and Construction Contract suite of contracts in December 2015. The model has also been used in New Zealand since the early 2000s and in Australia.
References
Construction management | Early contractor involvement | [
"Engineering"
] | 655 | [
"Construction",
"Construction management"
] |
59,681,951 | https://en.wikipedia.org/wiki/Diagram%20%28mathematical%20logic%29 | In model theory, a branch of mathematical logic, the diagram of a structure is a simple but powerful concept for proving useful properties of a theory, for example the amalgamation property and the joint embedding property, among others.
Definition
Let be a first-order language and be a theory over For a model of one expands to a new language
by adding a new constant symbol for each element in where is a subset of the domain of Now one may expand to the model
The positive diagram of , sometimes denoted , is the set of all those atomic sentences which hold in while the negative diagram, denoted thereof is the set of all those atomic sentences which do not hold in .
The diagram of is the set of all atomic sentences and negations of atomic sentences of that hold in Symbolically, .
See also
Elementary diagram
References
Mathematical logic
Model theory | Diagram (mathematical logic) | [
"Mathematics"
] | 169 | [
"Mathematical logic stubs",
"Mathematical logic",
"Model theory"
] |
59,683,697 | https://en.wikipedia.org/wiki/Turkish%20Space%20Agency | The Turkish Space Agency (, TUA) is a government agency for national aerospace research as a part of the space program of Turkey. It was formally established by a presidential decree on 13 December 2018.
Headquartered in Ankara, the agency is subordinated to the Ministry of Industry and Technology. With the establishment of TUA, the Department for Aviation and Space Technologies at the Ministry of Transportation and Infrastructure was abolished. TUA prepares strategic plans that include medium and long-term goals, basic principles and approaches, objectives and priorities, performance measures, methods to be followed and resource allocation for aerospace science and technologies.
TUA works in close collaboration with the TÜBİTAK Space Technologies Research Institute (TÜBİTAK UZAY). It is administrated by an executive board of seven members. The tenure of board members, the chairperson excluded, is three years.
Internationally, TUA currently has agreements with Ukraine, Hungary and Kazakhstan's space programs, and claims to conduct extensive nation-wide assessments regarding membership to ESA since 2020 as part of Turkey's cooperation agreement with the agency in 2004.
Administrators
List of TSA astronauts
See also
List of government space agencies
Science and technology in Turkey
Turkish Space Systems, Integration and Test Center
Space Launch System (Turkey)
Space Camp Turkey
Turkish Aerospace Industries
References
Space agencies
Research institutes in Turkey
Aviation in Turkey
Aerospace research institutes
Space technology research institutes
Aeronautics organizations
Organizations based in Ankara
Space program of Turkey
2018 establishments in Turkey
Government agencies established in 2018
Government agencies of Turkey | Turkish Space Agency | [
"Engineering"
] | 299 | [
"Aeronautics organizations"
] |
59,684,533 | https://en.wikipedia.org/wiki/Miliana-Margueritte%20Tramway | The Miliana-Margueritte Tramway or Zaccar Mines Tramway was a long steam and diesel powered gauge railway from PLM's Miliana-Margueritte station to the iron ore mines on Mont Zaccar in Miliana, Algeria.
Historical background and foundation
On 16 September 1874, the governor granted a 17-year general mining concession to Messrs. Dupin and Allemand.
On 5 March 1888, the brothers Giraud, two bankers from Oran, received an extension of this concession until 1 July 1906.
On 22 March 1904, the public company Société des Mines du Zaccar was founded in Paris. The purpose of the company was the exploitation of mineral deposits and the construction and operation of all railways required for the transport of ores and metals for a period of 60 years.
Operation
The operation started on 7 October 1904, with an initial production of an average of 300 tons of iron ore per day. The production in 1905 already 87 879 tonnes. The railway was accepted for public use on 18 September 1908 and publicly operated from 14 October 1909. The transport volume rose until 1912 to a maximum of 227,000 tons per year. In 1927, as a record even 293,870 t were reduced.
The steam locomotive Jeanne could pull six large, funnel-shaped iron wagons filled with ore. These cars had a movable floor and transported 5 to 10 tons each. The Societe Anonyme des Mines du Zaccar took 1912 one of the first eight-wheel Garratt locomotives in operation. On 4 August 1926, a decree was passed, according to which the concession and modification of the operating conditions of the tram from Miliana to Margueritte by the Prefect of Algiers of 24 December 1925 were approved.
The underground mine employed up to 2,000 workers, or about every fourth worker in the city of Miliana. The mine and its railway were decommissioned on 31 December 1975. The mines and their railway closed on 31 December 1975.
Locomotives
Literature and art
Abdelkader Hadj-Hamou (born 1891 in Miliana, died 1953) described in 1925 a ride on the tram in his book Zhora, la femme du Mineur.. He was son of the judge of the city of Miliana, court interpreter, professor of Arabic and almost 20 years chairman of the Grand Mosque.
The Dutch painter Bart van der Leck has produced a large number of studies of the mines and their rail vehicles, which have been purchased, archived and exhibited by the German-Dutch art collector Helene Kröller-Müller.
References
External links
Les Mines du Zaccar (WayBackMachine, with several photos)
Rail transport in Algeria
Mining railways
750 mm gauge railways
Mining in Algeria
Iron ore railways | Miliana-Margueritte Tramway | [
"Engineering"
] | 550 | [
"Mining equipment",
"Mining railways"
] |
59,686,333 | https://en.wikipedia.org/wiki/Yongfeng%20chili%20sauce | Yongfeng chili sauce () or Yongfeng hot sauce is a traditional product made at Yongfeng, Shuangfeng County, Hunan, China. It is recognized by China as a Geographical Indication Product.
Yongfeng chili sauce is made of Yongfeng chili, polished glutinous rice, wheat, soybeans, and salt. It is prepared by boiling, grinding, mixing, fermenting, and aging, and produces a dark red, spicy sauce.
Characteristics
The finished sauce is a translucent reddish-brown with an amber luster, fragrant with Yongfeng pepper and wheat, and has a mellow sweet and spicy flavor.
History and culture
People began to make chili sauce in the Yongfeng area during China's Ming dynasty during the reign of Chongzhen Emperor. The chili sauce has been made in Yongfeng for more than 300 years.
Annual production starts after the Dragon Boat Festival as the rainy season ends. Home cooks make their own sauces, and rooftops of houses often have a sauce tank fermenting in the sun.
Along with Xiangtan lotus seeds and Changsha stinky tofu, Yongfeng chili sauce is known as "Hunan Sanbao" or one of Hunan's three treasures.
Business and economics
According to a government report, Yongfeng chili sauce sales revenues were nearly 100 million yuan in the year 2000, representing taxes and profits of 30,000,000 CNY (US$4,469,550) for Shuangfeng county.
By 2009, there were more than 100 chili sauce production enterprises in Shuangfeng county, including 3 enterprises with an annual production capacity of over 2,000 tons.
Ingredients and production
Yongfeng chili sauce can be made with bell pepper, cow-horn pepper and line pepper.
Industrial production
The Chinese government in 2007 approved an application for Geographical Indication Products status for Yongfeng chili sauce, specifying the ingredients and their proportions for industrial production. These are:
50% fresh Yongfeng red pepper, bell pepper, horn pepper
7% wheat flour
3.5% glutinous rice flour
2.5% soybean powder
25% water
9% salt.
The specified process calls for boiling the soybean, wheat, and rice flours, crushing or grinding the chili pepper, adding salt, then a natural fermentation process in which the sauce is set in the sun in open containers to ferment and form koji.
Home production
Local farmers and many families each have an inherited family recipe, which they adjust according to family members' flavor preferences. For example, some local vegetables named Dao Dou (sword bean Canavalia gladiata (Jacq.) DC.) and Di Can (Stachys geobombycis C. Y. Wu) are added into the chili sauce in Yuan Xiao village.
The quality of the sauce relies on the weather. The mixed materials need to be exposed under strong sunshine for about 40 days until the color of the sauce is dark red and the aroma is overflowing. Usually, the sunshine near the summer season in Shuangfeng county is qualified. Traditionally, the fermentation is taken under sunshine, but for some industrial process, temperature controlled fermentation technology is usually a guarantee of production and quality.
References
Further reading
Intangible Cultural Heritages of Hunan Province (Volume 3)
Hunan cuisine
Chili sauce and paste
Chili pepper dishes
Chinese sauces
Chinese condiments
Fermented foods
Chinese products with protected designation of origin | Yongfeng chili sauce | [
"Biology"
] | 705 | [
"Fermented foods",
"Biotechnology products"
] |
59,686,459 | https://en.wikipedia.org/wiki/Material%20extrusion-based%20additive%20manufacturing | Material extrusion-based additive manufacturing (EAM) represents one of the seven categories of 3D printing processes, defined by the ISO international standard 17296-2. While it is mostly used for plastics, under the name of FDM or FFF, it can also be used for metals and ceramics. In this AM process category, the feedstock materials are mixtures of a polymeric binder (from 40% to 60% by volume) and a fine grain solid powder of metal or ceramic materials. Similar type of feedstock is also used in the Metal Injection Molding (MIM) and in the Ceramic Injection Molding (CIM) processes. The extruder pushes the material towards a heated nozzle thanks to
the controlled axial movement of a piston inside a heated barrel,
or the controlled axial rotation of a screw inside a heated barrel,
or the controlled rotation of two feeding rollers.
Process of Creating EAM Metal Parts
The process for creating material extruded metal parts typically involves several stages, transforming them from plastic/metal composites to fully metal parts.
Printing: The process begins with printing the part using a filament containing metal powder bound in plastic. This filament, similar to that used in conventional FFF printers, is infused with metal. The printer deposits the metal-infused filament layer by layer, building up the shape of the part. These printed parts are referred to as "green" parts. To compensate for predictable shrinkage during the subsequent sintering process, the green parts are scaled up by 15-20% from their final dimensions.
Debinding: After printing, the green parts are placed in a debinding station. In this step, an organic solvent dissolves most of the plastic binding material. Consequently, the green parts transition into "brown" parts. The debinding process eliminates excess plastic, leaving behind a structure of metal powder.
Sintering: The brown parts, now washed, are transferred to a sintering furnace. This furnace adheres to a material-specific profile, depending on the material used. Initially, it burns away any remaining binder. Subsequently, it consolidates the metal powder, transforming it into a fully dense, finished metal part. The sintering process is integral as it ensures that the part attains its required mechanical properties.
Use: At this stage, the part becomes a fully metal component, ready for use.
History
R&D developments
In 1995, the Fraunhofer IFAM designed a Rapid Prototyping system, starting from a powder‐binder mixture which is squeezed out through a computer‐controlled nozzle. Parts are manufactured layer by layer and the “green parts” are debinded and sintered to reach their final density; IFAM restarted this line of research in 2017;
In 1998, the concept of hybrid, additive/subtractive Shape Deposition Manufacturing for ceramics was proposed and tested at Carnegie Mellon University
In year 2000, a system was developed at Rutgers University for the solid freeform fabrication of multiple ceramic actuators and sensors, starting from green ceramic filaments
In 2005, a system was development at the Drexel University, based on material extrusion, consisting of a mini-extruder with a single screw mounted on a high-precision positioning system, fed with bulk material in granulated form (pellets);
In 2015, a 3d printing machine was developed at Politecnico di Milano for MIM metals and CIM ceramics, based on extrusion of pellets with a stationary piston-based extruder over a reversed Delta Robot table;
In 2016, developments in multi-material printing have enabled material extrusion printers to utilize ceramic-based support materials, designed for easy removal. This advancement significantly facilitates the creation of complex geometries, as the support material can be effortlessly broken off after printing. A notable example is Desktop Metal’s machine, which employs a ceramic interface layer on all support structures. This feature ensures that the supports can be snapped off with minimal effort, enhancing the overall efficiency and precision of the printing process.
In the past few years, advances in material science and the expansion of material extrusion systems at companies like Markforged, Desktop Metal, and ALM3d have expanded the range of materials suitable for material extrusion printers. Some of these materials include: Stainless Steel, Low-Alloy Steel, Tool Steel, Aluminum 6061, Bronze, Chromium Zirconium Copper, Cobalt Chrome, or even gold.
Commercial developments
After year 2015, some commercial providers of the technology have started proposing their product, mostly for metal applications, e.g.:
Metal X by Markforged,
Studio System by Desktop Metal,
ExAM by AIM3d.
Reference List
Manufacturing
3D printing
3D printing processes
Fused filament fabrication | Material extrusion-based additive manufacturing | [
"Engineering"
] | 979 | [
"Manufacturing",
"Mechanical engineering"
] |
59,686,859 | https://en.wikipedia.org/wiki/List%20of%20invasive%20fungi | Some fungi are considered invasive species in certain parts of the world:
Amanita muscaria
Amanita phalloides
Batrachochytrium dendrobatidis
Batrachochytrium salamandrivorans
Carpenterella
Cryphonectria parasitica – causes chestnut blight
Cucumispora dikerogammari
Geosmithia morbida which, in partnership with the walnut twig beetle Pityophthorus juglandis, causes thousand cankers disease
Heterobasidion irregulare
Hymenoscyphus fraxineus
Puccinia horiana – causes Chrysanthemum white rust
Puccinia psidii
Pucciniastrum americanum
Ophiognomonia clavigignenti-juglandacearum
certain Ophiostoma species which cause Dutch elm disease
Ophiostoma ulmi
Ophiostoma himal-ulmi
Ophiostoma novo-ulmi
Pseudogymnoascus destructans
Uredo rangelii
Suillus and Rhizopogon are considered invasive in parts of the Southern Hemisphere, as they promote Pinaceae tree invasion.
References
fungi
Invasive fungi | List of invasive fungi | [
"Biology"
] | 240 | [
"Fungi",
"Lists of fungi"
] |
59,687,407 | https://en.wikipedia.org/wiki/Test%20article%20%28food%20and%20drugs%29 | In medicine and food law, a test article is a prototype product specifically manufactured to test the product. Since medical and food test products involve human safety, they are subject to legal regulation.
United States
In the United States, medical and food test products are regulated by the Food and Drug Administration (FDA).
Title 21 "Food and Drugs" , Part 50 "Protection of Human Subjects" defines test article as "drug (including a biological product for human use), medical device for human use, human food additive, color additive, electronic product, or any other article subject to regulation under the act or under sections 351 and 354-360F of the Public Health Service Act (42 U.S.C. 262 and 263b-263n)." Title 21 "Food and Drugs" , Part 58 "Good Laboratory Practice for Nonclinical Laboratory Studies" defines test article similarly: as "any food additive, color additive, drug, biological product, electronic product, medical device for human use, or any other article subject to regulation under the act or under sections 351 and 354-360F of the Public Health Service Act".
Generally, prior to the usage of test articles in research involving human subjects, and approval from the institutional review board (IRB), however emergency life-threatening situations are exempt form this requirement. IRB must be notified about an emergency usage of test articles within 5 business days.
References
Prototypes
Food law
Medical research
Medical tests | Test article (food and drugs) | [
"Chemistry"
] | 295 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
59,687,894 | https://en.wikipedia.org/wiki/IEC%2061000-4-4 | IEC 61000-4-4 is the International Electrotechnical Commission's immunity standard based on electrical fast transient (EFT) / burst transients. This publication is part of the greater IEC 61000 group of standards which is covered under IEC TR 61000-4-1:2016. The current third version of this standard (2012) replaces the second version (2004). The goal of this standard is to establish a common and reproducible reference for evaluating the immunity of electrical and electronic equipment when subjected to electrical fast transient/bursts on supply, signal, control and earth ports.
Note: This tables purpose is a quick overview. It does not contain the same level of detail as the official IEC 61000-4-4.
The cause of electrical fast transients (EFT) come from an arc when mechanical contact is open due to a switching process. Given the fast rise time and voltage of these pulses having a solid ground connection is important during the testing process. Testing for EFT often requires a capacitive coupling clamp (CCL), which is employed to add disturbances to nominal signals.
See also
IEC 61000-4-2
IEC 61000-4-5
Electromagnetic pulse
Surge protection
List of common EMC test standards
List of IEC standards
List of EN standards
References
International Electrotechnical Commission
Electromagnetic compatibility | IEC 61000-4-4 | [
"Engineering"
] | 271 | [
"Electromagnetic compatibility",
"Radio electronics",
"International Electrotechnical Commission",
"Electrical engineering organizations",
"Electrical engineering"
] |
59,688,553 | https://en.wikipedia.org/wiki/Fiona%20Meldrum | Fiona C. Meldrum is a British scientist who is a Professor of Inorganic Chemistry at the University of Leeds where she works on bio-inspired materials and crystallisation processes. She won the 2017 Royal Society of Chemistry Interdisciplinary Prize.
Education
Meldrum studied the Natural Sciences Tripos at the University of Cambridge, graduating in 1989. She joined the University of Bath for her postgraduate studies, working on bio-inspired systems where she completed her PhD on nanoscale synthesis in 1992.
Career and research
Meldrum was appointed a postdoctoral research fellow at Syracuse University, where she worked on nanoparticle assembly with Janos Fendler. Whilst there, she contributed to the book Biomimetic Materials Chemistry.
Meldrum was a Humboldt Research Fellow at the Max Planck Institute for Polymer Research, working on crystallisation using surface plasmon spectroscopy with Wolfgang Knoll. She explored chemical deposition of PbS on gold using self-assembled monolayers. Following this position, she worked at the Australian National University on biomineralisation.
Meldrum joined Queen Mary University of London as a lecturer in 1998. She moved to the University of Bristol in 2003, where she established new techniques to control crystal morphologies. In 2009 Meldrum was appointed as a Professor at the University of Leeds.
Meldrum was awarded an Engineering and Physical Sciences Research Council Fellowship in 2010. Her fellowship considers confined crystallisation in biological systems. She studied the crystallisation of calcium carbonate and calcium phosphate and their behaviour in confined systems. She demonstrated that confinement slows crystallisation, stabilising metaphases. Confined crystallisation can be used to control the polycrystalline structure of crystals. Supported by the Leverhulme Trust, Meldrum showed that even nanoscale confinement can template crystallisation. Meldrum looks to use biology to guide crystal growth, demonstrating precipitation with mould and via an amorphous precursor phase. She also looked how water-soluble block copolymers can influence the crystallisation of barium sulfate and calcium carbonate.
Meldrum's work uses nature as an inspiration for materials design. She focuses on biominerals such as bones, teeth and shells. She monitors the amorphous and precursor phases of biological crystal formation. Meldrum uses nanoparticles as additives in crystal growth, using the particle surface chemistry to tune particle occlusion. Amongst several organic additives, Meldrum has incorporated amino acids into calcite. The choice of additive is guided by genetic algorithms, resulting in the production of crystals with desired properties. She has evaluated how the surface topography impacts ice crystallisation, showing acute geometries give rise to a confined crystalline, which is followed by the formation of a bulk phase.
The Meldrum group develop microfluidic devices to monitor crystallisation processes. Crystallisation is usually difficult to monitor, as precipitation occurs very rapidly and is severely impacted by impurities. Microfluidic devices offer more control of the crystallisation rate, providing reproducible conditions for crystal growth and the potential to analyse the growth in situ. Meldrum developed a Crystal Hotel to study crystallisation in a variety of environments and equilibrium conditions. Meldrum has developed a range of experimental techniques; including Bragg coherent diffraction imaging, Brewster angle microscopy, liquid-cell Atomic force microscopy (AFM) and Infrared spectroscopy.
Awards and honours
Meldrum was appointed lead editor of the Materials Research Society (MRS) Bulletin in 2016. In 2017, she was awarded the Royal Society of Chemistry Interdisciplinary Prize. She was awarded a European Research Council (ERC) advanced grant in 2018.
References
Living people
British women chemists
Alumni of the University of Bath
Alumni of the University of Cambridge
Inorganic chemists
Syracuse University faculty
Max Planck Institute for Polymer Research people
Academics of Queen Mary University of London
Academics of the University of Leeds
Year of birth missing (living people) | Fiona Meldrum | [
"Chemistry"
] | 787 | [
"British inorganic chemists",
"Inorganic chemists"
] |
59,689,693 | https://en.wikipedia.org/wiki/City%20Nature%20Challenge | The City Nature Challenge is an annual, global, community science competition to document urban biodiversity. The challenge is a bioblitz that engages residents and visitors to find and document plants, animals, and other organisms living in urban areas. The goals are to engage the public in the collection of biodiversity data, with three awards each year for the cities that make the most observations, find the most species, and engage the most people.
Participants primarily use the iNaturalist app and website to document their observations. The observation period is followed by several days of identification and the final announcement of winners. Participants need not know how to identify the species; help is provided through iNaturalist's automated species identification feature as well as the community of users on iNaturalist, including professional scientists and expert naturalists.
History
The City Nature Challenge was founded by Alison Young and Rebecca Johnson of the California Academy of Sciences and Lila Higgins of the Natural History Museum of Los Angeles County. The first event took place in 2016, in which Los Angeles competed against San Francisco and won in all three categories (most observations, most species, most participants). In 2017 the challenge expanded to 16 cities across the United States, with a different city winning in each category. In 2018 it expanded to 68 cities across the world, but US participation still dominated and San Francisco won in all categories. The 2019 challenge was more than doubled in scale and took the competition beyond its US roots, with Cape Town, winning two of the three categories.
In 2020, the organizers removed the competition aspect due to the COVID-19 pandemic, stating, "To ensure the safety and health of all participants, this year’s CNC is no longer a competition. Instead, we want to embrace the collaborative aspect of sharing observations online with a digital community, and celebrate the healing power of nature as people document their local biodiversity to the best of their ability." This change remained in effect for following years.
Results
Reference:
References
External links
Citizen science
Biological censuses
Biodiversity | City Nature Challenge | [
"Biology"
] | 407 | [
"Biodiversity"
] |
59,691,369 | https://en.wikipedia.org/wiki/Epistemic%20cultures | Epistemic cultures (often used in plural form) is a concept developed in the nineties by anthropologist Karin Knorr Cetina in her book Epistemic Cultures: How the Sciences Make Knowledge. Opposed to a monist vision of scientific activity (according to which, would exist a unique scientific method), Knorr Cetina defines the concept of epistemic cultures as a diversity of scientific activities according to different scientific fields, not only in methods and tools, but also in types of reasonings, ways to establish evidence, and relationships between theory and empiry. Knorr Cetina's work is seminal in questioning the so-called unity of science.
Knorr Cetina's anthropology
In practice, Knorr Cetina compares two contemporary important scientific fields: High energy physics and molecular biology. She worked as an anthropologist within two laboratories, along the line of the laboratory anthropology work by Latour and Woolgar. Her anthropological work is comparative and the two chosen scientific fields are highly mediaticized and easily distinguishable.
Epistemic cultures as a philosophical concept has been perused by numerous philosophical, anthropological or historical studies of science.
Two distinct publication regimes
High energy physics and molecular biology are very different as scientific fields belonging to two different epistemic cultures. They also are very different in terms of academic authorship. Biagioli describes this difference in terms of publications culture regarding number of authors per paper, distribution of contributorship within authors, preprint policy and he precisely chooses to oppose the very same domains.
References
Sociology of science
Anthropology
History of science
Philosophy of science | Epistemic cultures | [
"Technology"
] | 324 | [
"History of science",
"History of science and technology"
] |
59,692,321 | https://en.wikipedia.org/wiki/Phocaeicola%20plebeius | Phocaeicola plebeius, formerly Bacteroides plebeius, is a microbe found in the human gut, most often found in Japan natives. It is able to digest porphyran, a polysacchide from Porphyra seaweed (nori) that humans cannot digest on their own. The porphyranase-encoding gene Bp1689 is believed to have been derived from the microbe Zobellia galactanivorans via horizontal gene transfer, as part of a gene cluster containing other carbohydrate-active enzymes.
Composition of red algae Porphyra
Porphyra is a genus of red seaweed. The two main Porphyra used in Japanese dishes are P. yezoensis and P. tenera which are commonly used in sushi. Porphyra spp. also known as nori in Japan contains compounds such porphyrans and agaroses that are indigestible to people lacking P. plebius. Rhodophyta, the phylum of red algae, has a cell wall composed of sulfated galactans. Agarans, a main component of the cell wall is composed of alternating 3-linked β-D-galactose and 4-linked α-L-galactose. Porphyran is a water-soluble agaran found in Porphyra. The porphyran backbone is composed of roughly 30% 3-linked β-D-galactose and 4-linked 3,6-anhydro-α-L-galactose. The remaining 70% is composed of 4-linked α-L-galactopyranose-6-sulfate or 3-linked β-D-galactopyranose.
Horizontal gene transfer
P. plebeius is believed to have acquired a cluster of sugar-processing enzymes from Z. galactanivorans, a marine bacterium. The two most important transferred genes are Bp1689 (GH16 β-porphyranase) and Bp1670 (GH16 agarase), as the enzymes they make deal with sugars found in the molecule. (Other transferred genes, such as two GH86 aragases, a sulfatase, and various regulatory parts, play a role too.) Specifically, Bp1689 hydrolyzes the (1→4) linkage between β-D-galactopyranose and α-L-galactopyranose-6-sulfate in porphyran. Structurally it contains a TIM barrel domain and two β-sandwich domains.
A number of other genes are also transferred with Bp1789 and Bp1670. In total, 11 genes are believed to have been transferred: they do not occur in other Phocaeicola species (known as of 2010) and have sequence similarity of 48%-69% compared to orthologs in Z. galactanivorans. Moreover, transferred genes in both species are located in similar orders along their chromosome (i.e. they are syntenic). There are also genes related to the HGT in these 11.
In 2012, it was reported that Bacteroides thetaiotaomicron VPI-5482 has a related set of genes in the same order, albeit specialized to a different task: degradation of α-mannan, a fungal sugar. Discovery of this more intact cluster further confirms the role of HGT.
A different nomenclature of these genes use the gene family instead of chromosomal sequence numbers. In this scheme, Bp1689 is BpGH16B and Bp1670 is BpGH16A.
References
External links
Type strain of Bacteroides plebeius at BacDive - the Bacterial Diversity Metadatabase
Bacteroidia
Gut flora bacteria
Bacteria described in 2005 | Phocaeicola plebeius | [
"Biology"
] | 793 | [
"Gut flora bacteria",
"Bacteria"
] |
59,694,198 | https://en.wikipedia.org/wiki/Secure%20Scuttlebutt | Secure Scuttlebutt (SSB) is a peer-to peer communication protocol, mesh network, and self-hosted social media ecosystem. Each user hosts their own content and the content of the peers they follow, which provides fault tolerance and eventual consistency. Messages are digitally signed and added to an append-only list of messages published by an author. SSB is primarily used for implementing distributed social networks, and utilizes cryptography to assure that content remains unforged as it is propagated through the network.
In contrast to the major corporate social media platforms, user data and content on Secure Scuttlebutt is not monetized, there are no software design decisions being made in order to maximize user engagement or boost marketing metrics, and there is no paid advertising. According to Forbes, "Scuttlebutt itself isn't supported by venture capital. Instead ... Scuttlebutt is backed by grants that helped jump-start the process ... [and] there are now hundreds of users who personally donate to the cause and an estimated 30,000 people using one of at least six social networks on the protocol".
History
SSB was created by Dominic Tarr in 2014 as part of experimental development in alternative databases and distributed systems. Tarr lived on a sailboat with unreliable internet connection, and became interested in creating an offline-friendly secure gossip protocol for social networking. The word scuttlebutt is slang for "water-cooler gossip" among sailors. SSB gained popularity on the wave of privacy controversies raising against the traditional social media.
Protocol
Secure Scuttlebutt operates as a database of immutable append-only feeds, which allows resilient replication over the Internet, local area networks, and sneakernets. Messages are hashed with SHA256 and verified with an Ed25519 signature; this makes it impossible to forge a message without the private key of the author. Users only download messages from peers that they follow (and optionally friends of friends), which prevents harassment and spam. This makes the network invite-only, meaning that new peers who join the network aren't visible until someone follows them.
User content in SSB is organized as an append-only sequence of immutable messages, where messages cryptographically sign adjacent messages for the purpose of guaranteeing unforgeability of the sequences as they are replicated to other peers. SSB peers exchange asymmetric keys and establish authenticated connections between each other using an Authenticated Key Exchange protocol, Secret Handshake.
Applications and documentation
The reference implementation was written using Node.js, as code that runs on a JavaScript engine. There are active implementation efforts in the Go programming language, as well as in Python, and Rust. Documentation for these implementations can be found at the official SSB development site.
Many independent applications have been implemented on SSB, including a social network, music sharing, chess, a Git subsystem, and an npm registry.
See also
Nostr
Bluesky Social
Briar
Comparison of distributed social networks
Dat
Freenet
Git
IPFS
Mastodon
Perkeep
RetroShare
Urbit
ZeroNet
References
Further reading
External links
Manyverse – app for Android, iOS, Linux, MacOS & Windows
Patchfox – SSB client Firefox extension
Planetary Social – app for iOS & MacOS
Peer-to-peer computing
Mesh networking | Secure Scuttlebutt | [
"Technology"
] | 705 | [
"Wireless networking",
"Mesh networking"
] |
59,694,823 | https://en.wikipedia.org/wiki/JJ%20Eldridge | JJ Eldridge is a theoretical astrophysicist based in New Zealand. Eldridge is the head of the Department of Physics at the University of Auckland and co-author of The Structure And Evolution Of Stars.
Education and research
Eldridge obtained their MA and MSci from the University of Cambridge, England. They also obtained their PhD in astrophysics at Cambridge, in the Institute of Astronomy, with a thesis titled 'Progenitors of Core-Collapse Supernovae'. They worked as a postdoctoral researcher at the Institut d'astrophysique de Paris and Queen's University in Belfast, before returning to the Institute of Astrophysics at Cambridge. In 2011 they were appointed lecturer in astrophysics at the University of Auckland in New Zealand.
Eldridge studies the evolution of binary stars using numerical models. At the University of Auckland, together with , they co-developed the Binary Population and Spectral Synthesis (BPASS) models to study the evolution of stars. They used these models to show that globular clusters were younger than previously thought.
Together with Christopher Adam Tout, they wrote The Structure And Evolution Of Stars, published in 2019 by World Scientific Europe.
Eldridge is a Fellow of the Royal Astronomical Society and Fellow of the Astronomical Society of Australia.
LGBT+ advocacy
Eldridge is non-binary and is a strong advocate of LGBT+ inclusion. They sit on the Equity committee in the Faculty of Science at the University of Auckland. They also lead the Trans on Campus and Rainbow Science groups at the university. Their efforts have been recognised as key in winning the Pleiades Bronze Award by the Department of Physics at the University of Auckland. They also work with the Australian Society of Astronomy (ASA) on the Inclusive, Diverse, Equitable Astronomy (IDEA) group. For their work in LGBTI+ inclusion they were shortlisted for the New Zealand LGBTI Hero of the Year Award.
See also
LGBT people in science
References
External links
Living people
Year of birth missing (living people)
Astrophysicists
Alumni of the University of Cambridge
Transgender scientists
Academic staff of the University of Auckland
Transgender non-binary people
New Zealand transgender people
New Zealand non-binary people
20th-century New Zealand astronomers
21st-century New Zealand astronomers
Fellows of the Royal Astronomical Society
Transgender academics
Non-binary scientists | JJ Eldridge | [
"Physics"
] | 457 | [
"Astrophysicists",
"Astrophysics"
] |
59,695,080 | https://en.wikipedia.org/wiki/Blue%20loop | In the field of stellar evolution, a blue loop is a stage in the life of an evolved star where it changes from a cool star to a hotter one before cooling again. The name derives from the shape of the evolutionary track on a Hertzsprung–Russell diagram which forms a loop towards the blue (i.e. hotter) side of the diagram, to a place called the blue giant branch.
Blue loops can occur for red supergiants, red-giant branch stars, or asymptotic giant branch stars. Some stars may undergo more than one blue loop. Many pulsating variable stars such as Cepheids are blue loop stars. Stars on the horizontal branch are not generally referred to as on a blue loop even though they are temporarily hotter than on the red giant or asymptotic giant branches. Loops occur far too slowly to be observed for individual stars, but are inferred from theory and from the properties and distribution of stars in the H–R diagram.
Red giants
Most stars on the red-giant branch (RGB) have an inert helium core and remain on the RGB until a helium flash moves them to the horizontal branch. However, stars more massive than about do not have an inert core. They smoothly ignite helium before reaching the tip of the red-giant branch and become hotter while they burn helium in their cores. More massive stars become hotter during this phase and stars from about upwards are generally treated as experiencing a blue loop, which lasts on the order of a million years. This type of blue loop occurs only once in the lifetime of a star.
Asymptotic giant branch
Stars on the asymptotic giant branch (AGB) have largely inert cores of carbon and oxygen, and alternately fuse hydrogen and helium in concentric shells around the core. The onset of helium shell burning causes a thermal pulse and in some cases this will cause the star to temporarily increase its temperature and execute a blue loop. Many thermal pulses may occur as the shells alternately switch on and off, and multiple blue loops can occur in the same star.
Red supergiants
Red supergiants are massive stars that have left the main sequence and greatly expanded and cooled. Their high luminosity and low surface gravity means they are rapidly losing mass. The most luminous red supergiants can lose mass quickly enough that they become hotter and smaller. In the most massive stars, this can result in the star evolving permanently away from the red supergiant stage to become a blue supergiant, but in some cases the star will execute a blue loop and return to being a red supergiant. VY Canis Majoris is one such candidate for a star within a second red supergiant phase.
Instability strip
Stars which are executing blue loops cross the yellow portion of the H–R diagram above the main sequence, so that many of them cross a region called the instability strip because the outer layers of stars in that region are unstable and pulsate. Stars from the asymptotic giant branch that cross the instability strip during a blue loop are thought to become W Virginis variables. More massive stars, crossing the instability strip during a blue loop from the red-giant branch, are thought to make up the δ Cephei variables. Both types of star have luminous and unstable photospheres at this stage of their lives and often have the spectra of supergiants, although most are not massive enough to ever fuse carbon or reach a supernova.
Examples
Notable examples of stars believed to be in a blue loop phase include:
Canopus
Arneb
Eta Leonis
4 Lacertae
References
Stellar evolution
Hertzsprung–Russell classifications | Blue loop | [
"Physics"
] | 749 | [
"Astrophysics",
"Stellar evolution"
] |
59,695,673 | https://en.wikipedia.org/wiki/GD-42 | GD-42 (methylsulfomethylate) is an irreversible acetylcholinesterase inhibitor. It has a positively charged sulfonium group.
See also
Armine (chemical)
Paraoxon
Ro 3-0419
Ro 3-0422
V-sub x
References
Acetylcholinesterase inhibitors
Phosphonothioates
Sulfonium compounds
Ethyl esters | GD-42 | [
"Chemistry"
] | 84 | [
"Phosphonothioates",
"Functional groups",
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
59,695,988 | https://en.wikipedia.org/wiki/Oesterdam | The (English: Oyster Dam) is a compartmentalisation dam in The Netherlands, situated between Tholen and South Beveland in the eastern part of the Eastern Scheldt. The dam, with a length of 10.5 kilometres, is the longest structure built for the Delta Works. The Oesterdam was necessitated, like the Philipsdam, after the decision was taken to close off the Eastern Scheldt with a storm surge barrier, rather than a solid dam.
The dam contains a large sluice, the , and is located adjacent to a pair of sluices at Kreekrak, where about 80,000 ships pass every year.
Design background
The Oesterdam was not originally part of the planned Delta Works, but rather is one of the compartmentalisation dams which became necessary when it was decided not to close off the Eastern Scheldt, but to provide it with a permeable barrier.
The reduced tidal movement in the estuary associated with this decision meant that, to achieve sufficient tidal movement, the surface area of the Eastern Scheldt would have to be reduced. This was achieved by the construction of compartmentalisation dams: the Markiezaatskade, the Philipsdam, the Volkerakdam, and the Oesterdam.
With the construction of the compartmentalisation works, the freshwater was created, with benefits for agriculture. At the same time, a tide-free shipping route was created from the Volkerak locks to Antwerp.
The (English: Committee for Compartmentalisation of the Eastern Scheldt) was formed under the aegis of the Dutch Minister of Transport and Water Management. Its mandate included reporting to both the minister and the provincial authorities of Zeeland and North Brabant by 30 April 1975. This report was to cover the technical, planning, and financial considerations of various proposals for compartmentalising the Eastern Scheldt.
The necessity of this committee arose from the need to maintain a substantial tidal difference at Yerseke and to ensure tide-independent inland navigation between Antwerp and Rotterdam, in accordance with an existing treaty with Belgium. The committee evaluated multiple alternatives, each suggesting a unique design for the dam. The chosen plan for the Oesterdam entailed a path from the Scheldt-Rhine Canal through the Bathse polders in a northerly direction, incorporating a separate spillway channel leading to a sluice in the Western Scheldt – the Bathse sluice – along with enhancements to the Canal through South Beveland.
In the initial phases, the Bathse spillway channel's dam body was positioned west of the Kreekrak locks, intended to become operational concurrent with the completion of the Oesterdam. The proposed lock connecting the Zoommeer and the Eastern Scheldt was planned to be situated southwest of the Tholense Gap. This location was selected for its feasibility and its connection to an easily constructible section of the dam over the Speelmansplaten. This configuration resulted in two remaining gaps, the Marollegat and the Tholense Gap, that needed closure.
Construction
Construction began after the completion of the Markiezaatskade dam (1981 - 1983), the tidal effects of the completed dam making the construction of the Oesterdam easier. The initial strategy for the Oesterdam's construction involved using a sand closure for the extensive southern segment up to the new Bergse Diepsluis, and completing the section from the Bergse Diepsluis to Tholen with a cable car and concrete blocks. Construction commenced in 1979 with the establishment of a work island on the Speelmansplaten, which was completed by 1980.
The geotechnical and engineering geology challenges during the construction of the Oesterdam were substantial. The Holocene strata, extending from N.A.P. -5 m to -16 metres, were irregular, consisting of sand, peat, and clay layers of varying thickness. Beneath these, Pleistocene layers included deposits of sand with interspersed clay and shell grit. Towards Speelmansplaten and the Marolle Gap, the Holocene layer's thickness decreased, indicating lesser erosion over time.
In some areas, thick deposits of the Dunkirk clay formation were directly on top of peat, or beneath a sand covering. Significant erosion by the Scheldt river had previously formed a valley in the southernmost 100 metres of the works, which had later filled with a complex mix of clay and sand.
Geotechnical investigations had revealed poor subsoil quality at the Speelmansplaten and Marolle Gap dike sections. To minimise instability risks during construction, various solutions were explored, such as supporting berms, vertical drainage, soil improvement, and phased construction with specific profiles to ensure stability.
For the construction of the dam body, particular attention was paid to the soil structure. The design followed the top of the load-bearing Pleistocene sand. A uniformly wide base width of 76 metres was adopted for simplicity, widened to 110 metres near the last closing gap of the Marolle Gap to minimise instability risks. In the South dike section, the subsoil allowed for direct construction on the existing ground over 100 metres. The termination of the excavation work was strategically planned to ensure stability. Specific requirements were set for dam body construction in transition areas, focusing on maintaining stability and integrity.
The dam was then constructed in stages. Owing to delays and advancements in dredging technology, which offered increased capacities at relatively lower costs, it was later decided to execute the Tholense Gat closure also with sand. This approach necessitated creating an extended tidal curve for several days, by partially closing the Oosterscheldekering. An assessment of the environmental impact of this method deemed it acceptable.
The dredging vessels used on the project included the Aquarius, the Sliedrecht 27, the Zuiderklip, and the Mercurius. The production data of some of the dredgers, showing the increase in output from the originally planned sand closure volumes, is presented in the table below:
In 1986, the dam's closure was executed using sand as the primary material. The construction of the road (N659) across the dam was completed in 1989. This new route was inaugurated by the Commissioner of the King, Kees Boertien, marking its official opening to the public.
The Bergse Diepsluis, situated at the northern extremity of the dam, stands on the historical site of the submerged city of Reimerswaal. The city was destroyed by repeated floods, and the last citizens left in 1632. Recognising the historical significance of the area, an information centre was established at the Bergse Diepsluis in July 2022. This centre serves as a memorial and educational point, detailing the history of approximately 250 villages in Zeeland that were submerged in Reimerswaal (in the period 1550-1650) and elsewhere in the province.
Gallery
See also
Delta Works
Flood control in the Netherlands
Rijkswaterstaat
References
External links
Information on the Oesterdam from the official Watersnoodmuseum website
Delta Works
Dams completed in 1986
Dams in Zeeland
Zuid-Beveland | Oesterdam | [
"Physics"
] | 1,471 | [
"Physical systems",
"Hydraulics",
"Delta Works"
] |
59,696,041 | https://en.wikipedia.org/wiki/Markiezaatskade | The is a compartmentalisation dam in The Netherlands, situated between South Beveland and , near Bergen op Zoom. The dam was constructed as part of the Delta Works, and has a length of .
The dam was conceived as an auxiliary dam to permit the construction of the Oesterdam, and encloses the Markiezaat area of Bergen op Zoom. Without this structure, the location of the Oesterdam would have been situated more to the west, which would have resulted in negative ecological impacts for shellfish and resulted in significantly higher costs for the dam. In combination with the Oesterdam, Philipsdam and Volkerakdam, it divides the waters of Zeeland and South Holland.
Construction of the Markiezaatskade commenced in 1980. In March 1982, during construction, a part of the dam was destroyed by a storm. Construction on the dam was completed by March 30, 1983.
Design and construction
The dam is L-shaped, with a northern part between Molenplaat and Noordland, a western part between Molenplaat and Kreekrak locks, and a discharge structure in its western embankment. Constructed to facilitate the construction of the Oesterdam, it divides (along with the Oesterdam, Bathse Spuis Lock, Bathse Spuis Canal, and Philipsdam) the Zeeland and South Holland waters into compartments for the management of freshwater and navigation.
Along with the Oesterdam, it forms the limit of the freshwater . The construction of the dam created the Markiezaatsmeer wetland. The purpose of the Markiezaatskade was to permit easier construction of the Oesterdam and improve the ecological quality of the area. Since the construction of the Oesterdam was completed, it does not play a role in storm surge protection.
An area of land behind the current dam location was permanently flooded during the Saint Felix flood of 1530. The dam is located in the estuary of the Eastern Scheldt, where the North Sea meets the Scheldt, with a tidal range of up to five metres. The Markiezaatskade construction cut off this water from tidal influence.
Most of the dam was built with sand, except for the 800-metre-long closing gap in the western leg, which was to be filled with a temporarily porous closing dike. This dike was intended to gradually silt up over the years naturally, with the aim of slowly transitioning the from a saline waterbody to a freshwater lake.
The original probabilistic design had utilised relatively low dam sections, mainly driven by financial considerations, with a construction schedule planning for the closure works to be undertaken in summer. However, due to delays, the closure shifted to winter. Construction of the dam faced delays due to the extremely soft subsoil. In the spring of 1982, during the placement of armourstone, a small unfinished section of the dam stood only 2.25 meters above the Amsterdam Ordnance Datum (NAP). On 11 March 1982, a minor but intense storm coinciding with a spring tide caused a sudden rise in the Oosterschelde basin's water level.
The swift escalation in water levels was partially attributed to the peak wind speeds coinciding with the period of high water. Consequently, and due to the closure dike already extending over half its length at 4 metres above NAP, the water level in the Markiezaat remained markedly low, around 0.6 metres above NAP at the time of the high tide. This posed a threat to the stability of the dam head. A 40-tonne crawler crane was stationed on the dam, and could not be removed due to the unforeseen and sudden rise in water levels, thereby exacerbating the stability issues on the dam.
This unexpected surge, which reached 3.67 meters above NAP, caused significant overflow and ultimately led to a breach in the incomplete section, resulting in substantial damage. In a few days, a gap of approximately 150 metres wide formed in the dike, and scour pits with depths of up to 26 metres below NAP on the east side, and 22 metres below NAP on the west side, were formed. The eastern scour pit quickly expanded in the direction of a nearby high-voltage electricity mast.
After the breach, emergency measures were taken to ensure the stability of the high-voltage electricity mast and to reduce hindrance to navigation on the Scheldt-Rhine waterway. To repair the breach, various options were examined. Eventually, it was decided to proceed with a new closure and to strengthen and raise the existing northern and southern dam sections.
Completion and environmental functions
After the completion of the Oesterdam in 1986, the Markiezaatskade took on its final environmental function, as a water barrier between Bergen op Zoom and the Scheldt-Rhine connection. This separation was necessary to isolate the nature reserves in and around the Markiezaatsmeer from the Scheldt-Rhine Canal, which could not be protected from pollution due to the presence of locks and shipping.
Subsequently, the Markiezaatsmeer became the largest wetland area in the Netherlands after the Wadden Sea and the IJsselmeer. Most species of breeding birds in the Netherlands can be found there, with a large colony of spoonbills arriving in the spring. Orchids grow along the walking paths, and the lake also serves as a freshwater buffer for the surrounding area.
Gallery
References
Further reading
Delta Works
Dams completed in 1983
Dams in Zeeland
Dams in North Brabant
Zuid-Beveland
Buildings and structures in Reimerswaal
Transport in Reimerswaal | Markiezaatskade | [
"Physics"
] | 1,154 | [
"Physical systems",
"Hydraulics",
"Delta Works"
] |
76,342,939 | https://en.wikipedia.org/wiki/FAM81A | FAM81A is a protein that in humans is encoded by the FAM81A gene which is expressed in the postsynaptic density of the brain. It plays a pivotal role in forming postsynaptic protein agglomerations, essential for synaptic function in the brain.
References | FAM81A | [
"Chemistry"
] | 63 | [
"Biochemistry stubs",
"Molecular and cellular biology stubs"
] |
76,343,190 | https://en.wikipedia.org/wiki/Blockchain-based%20Service%20Network | The Blockchain-based Service Network (BSN) is a backend architecture in China for developing and managing blockchain-based applications, and is split into Chinese and International uses. BSN China, designed as the backbone of China's blockchain strategy, was established in 2018 and launched in 2020 by the State Information Center under the National Development and Reform Commission of China, China Mobile, China UnionPay(state-owned payment and settlement provider), and a technology architect. BSN International operates under the Singapore-based BSN Foundation.
The BSN integrates both private and public blockchain frameworks and cloud service providers to build the underlying development and production environment, where enterprises, governmental bodies, and financial institutions can build Blockchain-as-a-Service Systems and blockchain applications while being compliant with China's regulations of non-cryptocurrencies. BSN International draws on Amazon Web Services data centers in Hong Kong, California, and Paris, while BSN China utilizes Chinese domestic cloud infrastructure provided by China Mobile, China Telecom, and Baidu AI Cloud.
China's state-level decentralized identifier system, China RealDID, is deployed on BSN China.
As a digital infrastructure along the Belt and Road Initiative, the BSN works on interoperability across blockchain systems and develops a public IT system/multi-party system concept that uses blockchain as an operating system, including permissioned and permissionless blockchain infrastructures，such as Ethereum, Hyperledger and EOS.
In Sep 2022, BSN Spartan Network was launched in Hong Kong, targeting users outside of mainland China.
On November 8, 2023, BSN was listed in a US House of Representatives proposed bill aimed at preventing US federal agencies from utilizing China-developed blockchain networks or engaging with related companies due to national security concerns.
See also
Blockchain technology
China's Belt and Road Initiative
Digital currency in China
Interoperability in computing
Cloud computing
Blockchain as a Service (BaaS)
Blockchain-based database
References
Blockchains
Belt and Road Initiative
Distributed computing projects | Blockchain-based Service Network | [
"Engineering"
] | 442 | [
"Distributed computing projects",
"Information technology projects"
] |
76,344,116 | https://en.wikipedia.org/wiki/Ciguatoxin%201 | Ciguatoxin 1 or CTX-1 is a toxic chemical compound, the most common and potent type in the group of ciguatoxins. It is a large molecule consisting of polycyclic polyethers that can be found in certain types of fish in the Pacific Ocean. The compound is produced by Dinoflagellates Gambierdiscus toxicus and is passed on through the food chain by fish. The compound has no effect in fish but is toxic to humans.
History
Before ciguatoxin was discovered and identified, its presence in the food chain was hypothesised by Randall et al, who assumed that the toxin enters the food chain via herbivorous fish that feed on toxic microalgae and then gets passed on to humans directly or by passing through other carnivorous fish. This hypothesis was proven by Helfrich and Banner, who also showed that the toxin has no effect on fish, both herbivorous and carnivorous.
Ciguatoxin-1 was first discovered in 1967 by Scheuer et al when studying ciguatera fish responsible for food poisoning. Later on, in 1977 Yasumoto et al isolated the compound from Dinoflagellates and named it ciguatoxin, after which it was classified as a polyether compound. In the 1980s and early 1990s the full structure of ciguatoxin-1 was elucidated using NMR- spectroscopy, mass-spectrometry and X-ray crystallography. Due to the high complexity of its structure, ciguatoxin-1 has not been assigned an official IUPAC name and is denoted simply as ciguatoxin-1 or CTX-1.
As such the compound hasn't been found of any practical use in daily life. However, it has been shown useful for the studies of voltage gated sodium channels, where it can be used as a tool to alter the channel permeability and polarisability.
Ecosystem distribution
CTX-1 is produced by dinoflagellates called Gambierdiscus toxicus. These dinoflagellates are either free flowing in the water or associated to different types of microalgae. The toxin from the Gambierdiscus Toxicus accumulates in the fish that consume these organisms, and through the food chain the toxin eventually enters the human body. CTX-1 cannot fully be removed from the fish by cooking it. The toxin is found in tropical and subtropical coral reef fishes. Typically, these fishes are large predator fishes like moray eels, barracudas, snappers, Spanish Mackerels and groupers.
There have been studies suggesting the transmission of the toxin from a pregnant mother to the foetus, and from a nursing mother to her child. There have also been some reports about sexual partners of ciguatoxin poisoning patients also experiencing symptoms.
Food poisoning symptoms
Eating fish containing a high enough dose of CTX-1 causes Ciguatera Food Poisoning (CFP). It is suspected that concentration of 0.08 ug/kg fish is high enough to cause clinical symptoms and concentrations over 0.1 ug/kg fish are considered a health risk. There are different types of symptoms for CFP: gastrointestinal, cardiac, neurological and neuropsychological symptoms. Gastrointestinal symptoms include nausea, vomiting, abdominal pain and diarrhoea. These symptoms usually start to show within 6-12h of fish consumption and resolve spontaneously within 1-4 days. Cardiac symptoms include hypotension and bradycardia. These signs can lead to necessity of emergency medical care. The neurological and neuropsychological symptoms usually become prominent after the gastrointestinal symptoms appear and they usually become present within two days of the illness. The signs and symptoms include weakness, toothache, the sensation of loose teeth, paraesthesia, dysesthesia, itching, confusion, reduced memory, difficulty concentrating, sweating and blurred vision. A characteristic symptom is cold allodynia, sometime referred to as ‘hot-cold reversal’, which is characterised by an abnormal sensation when touching cold water or objects.
Mechanism of action
In neuronal neural tissue
One of the most prominent studies on the effects of P-CTX-1 on the neural tissue by Benoit et al in 1994 revealed that ciguatoxin-1 can induce spontaneous action potentials in frog myelinated neural fibres, that were eliminated by the addition of TTX. This allowed researchers to conclude that P-CTX-1 mechanism of action must involve voltage-dependent (Nav) sodium channels. Later in 2005, a similar study by Birinyi-Strachan et al confirmed this hypothesis by analysing the effects of P-CTX-1 on the excitability of rat dorsal root ganglion. This study has shown that ciguatoxin-1 can prolong the action potential and increase the afterhyperpolarisation of the cells.
It has also been shown that P-CTX-1 acts differently on TTX-sensitive and TTX-resistant cells: in the former, it causes leakage current and reduction in peak signal amplitude, while in the latter it causes the reduction of peak amplitude and increased recovery rate from inactivation. These findings show that different action mechanisms of P-CTX-1may contribute to the big variety neurological symptoms as each type of neural tissue reacts to ciguatoxin in a different manner.
Further studies were carried out to identify the mechanism of action of P-CTX-1 on Nav channels, which assumed a direct interaction between the toxin and the sodium channels. However, in 1992 Lewis disproved the original hypothesis and showed that the interaction is indirect, by the means of beta1-adrenoceptor stimulation.
In their study Birinyi-Strachan et al have also shown that P-CTX-1 can also block delayed rectifier voltage gated potassium channels in rat neurons, which could generally contribute to the overall membrane depolarisation, prolonged action potentials, increased afterhyperpolarisation, and lowered threshold for action potential firing. These findings could further explain the origin of various symptoms of ciguatera such as paraesthesia or dysesthesia.
It was also found that CTX-1 releases noradrenaline and ATP by asynchronous discharge of preganglionic perivascular axons. CTX-1 prolongs the action potential and afterhyperpolarisation duration. In a subpopulation of neurons, tonic action potential firing can be produced.
In the gastrointestinal tract
Even though ciguatera causes major gastrointestinal issues, so far P-CTX-1 hasn't been proven to have a direct effect on digestive systems. Terao et al showed that no morphological alterations were observed in the mucosa or muscle layers of the small intestine, despite the severe diarrhoea commonly observed upon P-CTX-1 administration. Other studies (Lewis et al 1984, Lewis, Hoy 1983) have shown that P-CTX-1 causes acetyl choline release from parasympathetic cholinergic nerve terminals, which suggests that nerve stimulation by P-CTX-1 is followed by nerve blockade, likely due to further nerve depolarisation.
Toxicokinetics
As of today, only several studies were carried out on the biodistribution and toxicokinetics of ciguatoxins, most of which were carried out in rats or in vitro.
In a study by Bottein et al in 2011 it was shown that in rats, detectable levels of P-CTX-1 were observed in liver, muscle and brain up to 96 hours after intraperitoneal and oral administration. The terminal half-lives were reported at 112 h and 82 h respectively. The main excretion route was shown to be faecal, with P-CTX-1 or its other polar metabolites being present in faeces for up to 4 days after administration.
Another article speculated that ciguatoxins might be biotransformed in vitro by the means of glucuronidation. However, it was shown that glucuronidation was not observed for any of the ciguatoxins used in the study (including P-CTX-1) by both rat and human, which could suggest the prevalence of other conjugation pathways in mammals
References
Ion channel toxins
Polyether toxins
Marine neurotoxins
Phycotoxins
Heterocyclic compounds with 7 or more rings
Oxygen heterocycles
Polyols | Ciguatoxin 1 | [
"Chemistry"
] | 1,788 | [
"Polyether toxins",
"Toxins by chemical classification"
] |
76,344,490 | https://en.wikipedia.org/wiki/Geometric%20symmetry%20%28book%29 | Geometric symmetry is a book by mathematician E.H. Lockwood and design engineer R.H. Macmillan published by Cambridge University Press in 1978. The subject matter of the book is symmetry and geometry.
Structure and topics
The book is divided into two parts. The first part (chapters 1-13) is largely descriptive and written for the non-mathematical reader. The second part (chapters 14-27) is more mathematical, but only elementary geometrical knowledge is assumed.
In the first part the authors describe and illustrate the following topics: symmetry elements, frieze patterns, wallpaper patterns, and rod, layer and space patterns. The first part also introduces the concepts of continuous, dilation, dichromatic and polychromatic symmetry.
In the second part the authors revisit all of the topics from the first part; but in more detail, and with greater mathematical rigour. Group theory and symmetry are the foundations of the material in the second part of the book. A detailed analysis of the subject matter is given in the appendix below.
The book is printed in two colours, red and black, to facilitate the identification of colour symmetry in patterns.
Audience
In the preface the authors state: "In this book we attempt to provide a fairly comprehensive account of symmetry in a form acceptable to readers without much mathematical knowledge [...] The treatment is geometrical which should appeal to art students and to readers whose mathematical interests are that way inclined." However, Joseph H. Gehringer in a review in The Mathematics Teacher commented "Clearly not intended as a popular treatment of symmetry, the style of the authors is both concise and technical [...] this volume will appeal primarily to those devoting special attention to this field,"
Reception
The reception of the book was mixed.
William J. Firey in his review for zbMATH Open praised the book for its "beautiful and appropriate figures" but criticised "a certain imprecision about such fundamental notions as pattern, ornament, crystal."
H.S.M. Coxeter in Mathematical Reviews also praised "this beautifully illustrated book", but took issue with the authors' artificially restricted approach to colour symmetry, describing it as "unfortunate" in comparison to that of A.V. Shubnikov and V.A. Koptsik in Symmetry in Science and Art, and C.H. MacGillavry's analysis of M.C. Escher's work in Symmetry aspects of M. C. Escher's periodic drawings.
H. Martyn Cundy in The Mathematical Gazette wrote positively about the book: "It assumes little beyond the most elementary knowledge, develops the mathematics it needs as it goes along [...] and conveys the reader on a fascinating journey from the human face to polychromatic symmetry groups in three dimensions." and concluded by saying "Altogether this is a wholly delightful volume, obviously destined to be a classic work of reference which every school and college library will need and want to have, and to be treasured as a thing of beauty and a possession for ever by all lovers of geometry." However, Cundy also had some criticisms of the selection of material, and of the use of some non-standard terminology.
In 1987, Branko Grünbaum and Geoffrey Colin Shephard writing in Tilings and patterns criticised the authors and their Russian predecessor N.V.Belov by saying that it is "clear that the groups of colour symmetries of chromatic plane patterns were not in the authors' minds."
Editions
First hardback edition published by Cambridge University Press in 1978
Reprint edition published by Cambridge University Press in 2008
Appendix: Subject coverage
References
External links
at the Internet Archive
Symmetry
Geometry
Tessellation
Patterns
1978 non-fiction books
Books about mathematics
Cambridge University Press books | Geometric symmetry (book) | [
"Physics",
"Mathematics"
] | 775 | [
"Tessellation",
"Euclidean plane geometry",
"Geometry",
"Planes (geometry)",
"Symmetry"
] |
76,344,503 | https://en.wikipedia.org/wiki/Lynne%20Cox%20%28scientist%29 | Lynne Cox is a British biochemist and research scientist into the molecular basis of human ageing at the University of Oxford. In 2023 she was awarded the Lord Cohen Medal.
References
Living people
Year of birth missing (living people)
Place of birth missing (living people) | Lynne Cox (scientist) | [
"Chemistry"
] | 56 | [
"Biochemistry stubs",
"Biochemists",
"Biochemist stubs"
] |
76,345,372 | https://en.wikipedia.org/wiki/Tantalocene%20trihydride | Tantalocene trihydride, or bis(η5-cyclopentadienyl)trihydridotantalum, is an organotanalum compound in the family of bent metallocenes consisting of two cyclopentadienyl rings and three hydrides coordinated to a tantalum center. Its formula is TaCp2H3, and it is a white crystalline compound that is sensitive to air. It is the first example of a molecular trihydride of a transition metal.
Synthesis
The synthesis of tantalocene trihydride was first reported by Green, McCleverty, Pratt, and Wilkinson in 1961. Tantalum pentachloride was added to a solution of sodium cyclopentadienide in tetrahydrofuran and an excess of sodium borohydride with yields reaching 60%, although the authors report that the preparation does not always succeed.
A more reliable and reproducible method was reported by Green and Moreau in 1978. A suspension of tantalocene dichloride in toluene was reacted with NaAlH2(OCH2CH2OCH3)2 and then hydrolyzed to form tantalocene trihydride, though with a lower yield of 42%.
Characterization
The high-field signals in the 1H NMR spectrum corresponding to the hydrides appear at τ = 11.63 ppm (δ = -1.63 ppm, 1H, t, J = 9 Hz) and τ = 13.02 ppm (δ = -3.02 ppm, 2H, d, J = 9 Hz). The peak splitting pattern is characteristic of A2B groupings, which means that there are two equivalent hydrides, and one non-equivalent hydride. The signal for the hydrogen atoms on the cyclopentadienyl rings appear at τ = 5.24 ppm (δ = 4.76 ppm, 10H, s).
A strong, sharp absorption band can be seen in the infrared spectra of TaCp2H3 at 1735 cm−1, which corresponds to the Ta-H bond stretching frequency.
As opposed to other metallocene hydrides, such as ReCp2H, MoCp2H2, and WCp2H2, TaCp2H3 does not behave as a base, even in trifluoroacetic acid. It is decomposed by aqueous acids. This is consistent with the fact that the tantalum center does not have any lone pairs, since all orbitals have been utilized in bonding with the ligands.
The two cyclopentadienyl rings are in a bent conformation as confirmed by neutron diffraction studies where the ring-to-tantalum-to-ring bending angle is 139.9°. The three hydrides lie in the same plane as the tantalum center with the three Ta-H bond distances being essentially equal (1.769(8) Å, 1.775(9) Å, and 1.777(9) Å).
Reactivity
Tantalocene trihydride has been found to be capable of activating C-H bonds by oxidative addition as seen through hydrogen/deuterium exchange, involved in the insertion of phosphines, and capable of forming post transition metal ethyl adducts.
Catalysis of hydrogen–deuterium exchange
Barefield, Parshall, and Tebbe discovered that when TaCp2H3 was heated at 100 °C in benzene-d6 under a hydrogen atmosphere, HD and D2 were detected along with H2 in the vapor phase in a ratio of 41.1 to 41.6 to 17.0 (H2:HD:D2). This indicates that there is catalytic exchange, and that the complex is able to cleave the C-D bonds of the solvent.
In another study by Foust et al., when TaCp2H3 was photolyzed for 36 h at 15 °C in benzene-d6, analysis of the evolved gases revealed that there was a mixture of H2, HD, and D2. If carbon monoxide was present in the reaction with toluene as a solvent, the CO containing product TaCp2(CO)H was formed through the intermediate species TaCp2H.
Activation of Csp3-H bonds by oxidative addition
Neufeldt et al. explored the activation of aliphatic C-H bonds by TaCp2H3 and related monosubstituted cyclopentadienyl rings experimentally and computationally. In order to go through oxidative addition, there must be an initial loss of H2 from TaCp2H3. Then, the monohydride complex can form a π-complex with an unsaturated solvent, such as benzene. Finally, the complex oxidatively adds to the C-H bond. Intramolecular and intermolecular C-H activation was found to be possible.
A σ-complex will form instead if the solvent used is aliphatic, such as octane. The authors observed a change in the hydride NMR signals due to H/D exchange when TaCp2H3 was heated to 120 °C for 48 h in octane-d18 and methylcyclohexyl-d14.
The loss of another hydrogen molecule from the products can lead to β-hydride elimination, which forms complexes of the TaCp2(H)L, with L being an unsaturated π-ligand, having their own reactivity.
Phosphine insertion
The first phosphido derivative of tantalocene was obtained by the insertion of ClPPh2 into the Ta-H bond, resulting in the precipitation of the white ionic compound [TaCp2H2(PHPh2)]Cl. Deprotonation of this compound results in pale yellow crystals of the dihydride phosphido complex TaCp2H2PPh2. Through X-ray diffraction studies, the Ta-P bond distance was 2.595(3) Å, which is typical of a single bond between tantalum and phosphorus.
ClPPh2 has been shown to insert into the niobium analogue, NbCp2H3. However, the deprotonation step results in the monohydride phosphido complex NbCp2H(PHPh2) instead. The authors of this article theorize that stabilization of hydrido phosphide complexes of the third row transition metals is due to higher M-H bond energy when compared to those of the second row.
Lewis acid-base adducts
TaCp2H3 can form Lewis acid-base adducts with AlEt3, GaEt3, ZnEt2, and CdEt2 at the unique hydride. As opposed to promotion of catalysis of olefin reactions with Lewis acids like AlEt3 such as in Ziegler-Natta catalysts, triethylaluminium seems to deactivate the hydride ligand toward ethylene insertion.
References
Organotantalum compounds
Cyclopentadienyl complexes
Hydrido complexes | Tantalocene trihydride | [
"Chemistry"
] | 1,516 | [
"Organometallic chemistry",
"Cyclopentadienyl complexes"
] |
76,345,844 | https://en.wikipedia.org/wiki/Verona%20astrolabe | The Verona astrolabe is an archaeological discovery unearthed in the vaults of a museum in Verona, Italy. Dating back to the eleventh century, this Islamic astrolabe is one of the oldest examples of its kind and is among the few known to exist worldwide. It appears to have been employed by Muslim, Jewish, and Christian communities spanning Spain, North Africa, and Italy over several centuries.
Described by historian Tom Almeroth-Williams of the University of Cambridge as the "world's first smartphone," the astrolabe served as a portable astronomical instrument capable of diverse functionalities. It provided users with a two-dimensional representation of the universe, enabling the plotting of star positions, calculation of time and distances, and even the development of horoscopes.
Initially doubted to be authentic, the Verona Astrolabe was authenticated as an eleventh-century artifact by Dr. Federica Gigante of Cambridge University's History Faculty. Her analysis, published in the journal Nuncius, confirmed its origins in Al-Andalus, the Muslim-ruled region of Spain during the medieval period. The astrolabe bears Hebrew inscriptions alongside Arabic, indicating its circulation within the Jewish diaspora community in Italy, where Hebrew was used in place of Arabic.
References
Astronomical instruments
Historical scientific instruments | Verona astrolabe | [
"Astronomy"
] | 260 | [
"Astronomical instruments"
] |
76,346,163 | https://en.wikipedia.org/wiki/Mezhigorje%20Formation | The Mezhigorje Formation is a geologic formation in Belarus and Ukraine that dates to the Early Oligocene. Rovno amber is found in this formation and it has been studied since the 1990s.
History
Small amounts of rough, partially worked, and fully shaped amber discovered in the Mezhigorje Formation suggest that between 13,300 and 10,500 BC, the amber was used by early humans.
Rovno amber was first collected from the Mezhigorje Formation during the 1950s on a small scale and the amber was initially used for burning. The amber was first used for jewellery in the 1970s when another outcrop was discovered.
In 1991, the outcrop discovered during the 1970s began to be mined and later became the Pugach Quarry, and in 1993, the Ukrainian government began to oversee excavations of the Mezhigorje Formation for the first time. Despite this, 90% of amber collected from the Mezhigorje Formation is extracted illegally and the trade is controlled by armed organised crime groups.
Geological context
The Early Oligocene Rovno amber is hosted in the Mezhigorje Formation, and it overlies the Late Eocene Obukhov Formation. The formation is found along the northwestern margin of the Ukrainian Crystalline Shield exposed in the Rivne region of Ukraine and across the border near Rechitsa in the Gomel Region of Belarus. The granite basement rock was overlain by sandy to clayey deposits that were host to alluvial amber.
The two formations total between in thickness, both containing interbeds or mixtures of brown coals and carbonized vegetation. Both formations are sandy to clayey in texture, with the Mezhigorje Formation containing mostly medium to fine grained sands of a greenish gray tone, and with occasional iron impregnation and layering.
References
Geology of Belarus
Geology of Ukraine
Amber | Mezhigorje Formation | [
"Physics"
] | 379 | [
"Amorphous solids",
"Unsolved problems in physics",
"Amber"
] |
76,346,249 | https://en.wikipedia.org/wiki/Obukhov%20Formation | The Obukhov Formation is a geologic formation in Belarus and Ukraine that dates to the Late Eocene; the Obukhov Formation is equivalent to the Prussian Formation of Russia.
Rovno amber is found in this formation, and 90% of amber collected from the Obukhov Formation is extracted illegally and the trade is controlled by armed organised crime groups.
Geological context
The Late Eocene Rovno amber is hosted in the Obukhov Formation, and it underlies the Early Oligocene Mezhigorje Formation. The formation is found along the northwestern margin of the Ukrainian Crystalline Shield exposed in the Rivne region of Ukraine and across the border near Rechitsa in the Gomel Region of Belarus. The granite basement rock was overlain by sandy to clayey deposits that were host to alluvial amber.
The two formations total between in thickness, both containing interbeds or mixtures of brown coals and carbonized vegetation. Both formations are sandy to clayey in texture, with the Obukhov Formation having more clayey glauconite-quartz plus sandy loess.
References
Geology of Belarus
Geology of Ukraine
Amber | Obukhov Formation | [
"Physics"
] | 236 | [
"Amorphous solids",
"Unsolved problems in physics",
"Amber"
] |
76,346,535 | https://en.wikipedia.org/wiki/History%20of%20the%20extraterrestrial%20life%20debate | The existence of extraterrestrial life is a scientific idea that has been debated for centuries. Initially, the question was purely speculative; in modern times a limited amount of scientific evidence provides some answers. The idea was first proposed in Ancient Greece, where it was supported by atomists and rejected by Aristotelians. The debate continued during the Middle Ages, when the discussion centered upon whether the notion of extraterrestrial life was compatible with the doctrines of Christianity. The Copernican Revolution radically altered mankind's image of the architecture of the cosmos by removing Earth from the center of the universe, which made the concept of extraterrestrial life more plausible. Today we have no conclusive evidence of extraterrestrial life, but experts in many different disciplines gather to study the idea under the scientific umbrella of astrobiology.
Ancient Greece
During the early days of the history of astronomy the things seen in the night sky were explained as the actions of mythological deities. However, it soon became evident that celestial objects move and behave in regular and predictable patterns, which helped in keeping track of time, tides, and seasons, crucial for ancient agriculture. Most ancient civilizations had great knowledge of astronomy but only used it for religious and practical needs. Ancient Greek astronomy sought to go beyond that and explain the architecture of the cosmos.
Thales of Miletus sought to explain the nature of the universe without relying on supernatural explanations, and reasoned that Earth was a flat disk floating on an ocean of water. The idea was not widely accepted even then, but it established the underlying idea that the universe is intrinsically understandable. Greek philosophers did not follow the scientific method but based their ideas on pure thought instead. However, their discussions laid some principles that would eventually lead to it, such as the rejection of supernatural explanations and that ideas would not be valid if they were contradicted by observable facts. They also developed geometry, which helped with architecture and other practical tasks, but also with astronomic observations.
The initial idea of a flat Earth covered by a celestial dome was soon discarded. Thales' student Anaximander proposed a full celestial sphere instead. He also noticed evidences of the curved surface of the world and proposed that the Earth was shaped like a cylinder. Most other Greeks, however, preferred the proposal of Pythagoras that Earth was a perfect sphere, as they associated circles and spheres with mathematical perfection. The model of the celestial sphere works for distant stars, which seem to be at fixed locations in the sky to the naked eye, but the Sun and the Moon move at different speeds and the other classical planets follow complex paths and vary in their brightness. This was explained by adding other layers to the celestial sphere. This was detailed in the Ptolemaic model. Aristarchus of Samos proposed instead that it is Earth that spins around the sun, which makes it easier to explain the retrograde motion of the classical planets, but this was rejected by other Greeks. They pointed out that if Earth moves a stellar parallax would change the location of stars in the sky during the year. Although stellar parallax does exist, stars are too far away from Earth, more than Greeks considered, to be noticeable by the naked eye.
The Greeks discussed as well the possible existence of other worlds, but did not consider the planets as such. In their view, the celestial sphere was a part of Earth and other potential worlds would have their own ones. There was consensus that the world was made of the four classical elements, earth, water, fire and air. From there, they had two opposite ideas: Atomists thought that all existence was composed by atoms, small and indivisible pieces of the four elements, and Aristotelians thought that the four elements were exclusive to Earth and that the universe was made of a fifth one, the Aether. The atomist view would allow the existence of other worlds, as the processes that created Earth may happen elsewhere as well. Although very few of their writings were preserved, it is known that early atomists Leucippus and Democritus thought that atoms should create other worlds the same way Earth was created. Epicurus said in his "Letter to Herodotus" that "There are infinite worlds both like and unlike this world of ours... we must believe that in all worlds there are living creatures and plants and other things we see in this world".
Aristotle and Plato opposed the idea of a plurality of worlds. Plato reasoned that there could be a single heaven, and that if there were several worlds the universe would be composite, eventually falling into dissolution and decay. Aristotle thought that the earth element would tend to fall to the center of the universe and fire to rise away from it, under that logic the existence of other worlds would not be possible. He also thought that Aether moves in circles, and for that reason the universe could not be spatially infinite. Aristotle also rejected the plurality of universes, or heavens, arguing that the universe has a Prime Mover that started it all. If there were more than one universe then there would be more than one Prime Mover, and he considered that idea to be impossible. This idea may be influenced by his theological views, as well as his views about physics and cosmology. He concluded that "The world must be unique... There cannot be several worlds".
The Greek ideas and debates expanded across the ancient world, beyond Greece. Epicureanism spread across the Roman Empire, with proponents such as Lucretius with his book De rerum natura. Alexander the Great made a series of military campaigns that expanded the Greek Macedonian Empire to the Middle East, founding the city of Alexandria in Egypt, which would house the Library of Alexandria which was eventually destroyed. Baghdad became a hub of learning and trade during the Islamic Golden Age. Many Islamic scholars studied at the Library and cited or translated the work of the Greek authors, which did not get completely lost. They were also in contact with Hindu scholars from India, who were in turn influenced by the Chinese works and discoveries. Thus, Baghdad created a synthesis of the combined works of Ancient Greece, India, China, and their own scholars. This knowledge spread across the Byzantine Empire, and finally returned to Europe when many scholars escaped from the fall of Constantinople.
Christianity
The views of the atomists fell under religious scrutiny when Christianity became a prominent religion. All Church Fathers who made mention of the idea of the plurality of worlds dismissed it as a heresy. The only exception was Origen, who did not believe in many worlds existing at the same time, but rather in worlds that may exist before and after Earth. He developed this idea to explain God's apparent lack of purpose and activities before creating the world. Augustine of Hippo rejected this idea, proposing that time only manifests in the motion of the material, which means that there was no time "before" the creation because time itself started with it. Thomas Aquinas discussed it in his Summa Theologica: according to John 1:10 "the world was made by Him", with "world" in singular, which would mean only one. A single world would also mean order, in contrast with the plurality of words held by atomists, who would believe in chance rather than in an "ordaining wisdom" creating it all. He cited the Aristotlean thought in his support; On the Heavens had been translated to Latin by Gerard of Cremona a few years before. He also considered that, as God was only one, he would create only one world to mirror his own perfection. However, the ideas of Aquinas were banned by the Condemnation of 1277: they considered that God was being analyzed in a very rational way, and that they were close to suggesting that God could not do certain things, such as creating infinite worlds. In the following years several scholars discussed the plurality of worlds and maintained that it was not a theological impossibility, even if they rejected it for other reasons.
William Vorilong was likely the first author to discuss the death and resurrection of Christ in the context of the plurality of worlds. He reasoned that if there were people on other worlds they would not be living in sin, because they would not descend from Adam and Eve, but they would still live by virtue of God. He assumed that the death of Christ would surely redeem the people of other worlds just as it did for humans on Earth, and did not consider fitting that God would repeatedly manifest at each different world.
Copernican revolution
Nicolaus Copernicus published De revolutionibus orbium coelestium in 1543, kickstarting the Copernican Revolution. This book restored and updated the old idea of Aristarchus that Earth spins around the sun. The new version was written with so much mathematical detail that it could contest the Ptolemaic model. By this time, scientists noticed several inaccuracies in the Ptolemaic model. They were more open to revising it, but largely kept using it because of the huge work involved in changing the tables. Copernicus thought that Earth spinning around the sun could provide a simpler explanation for the retrograde motion of the planets, and calculated the distance of the planets to the Sun. However, he kept the idea of circular orbits, and added several composite orbits to explain the errors caused by it. Although he correctly displaced the center of the Solar System, this first model turned out to be as inaccurate and as complex as the Ptolematic one, and did not get much supporters in the first decades.
A recurring problem for both models was the lack of quality data, as the telescope had not been invented yet and naked eye observations are highly inaccurate. The Danish Tycho Brahe sought to gather such data, by creating huge naked-eye observatories. On his deathbed, he asked his assistant Johannes Kepler to make sense of his observations, so that it did not feel like he lived in vain. Kepler initially kept the circular orbits, and eventually found a system that would explain all the data, except for a mistake of 8 arcminutes on the position of Mars. However, Kepler trusted the accuracy of Tycho's observations, and so refused his provisional results. Instead, he challenged the circular orbits and tried with other shapes. With orbits shaped as ellipses he could explain the recorded motion of all the planets, including Mars' retrograde motion, without using composite circles to do so. He compiled his final results as the Kepler's laws of planetary motion.
However, some scientists had concerns over the new model. Aristotle had once stated that Earth could not move because, if it did so, birds, clouds, and falling objects would be left behind. Orbits had to be circular because the heavens had to be perfect and unchanging. And if Earth moved, the stars should leave a stellar parallax. Those concerns were addressed by Galileo Galilei. First, he explained that an object in motion stays in motion unless a force stops it; a principle nowadays included in the first of Newton's laws of motion. The idea of heavenly perfection was already being challenged by Tycho's observations. Tycho had observed a supernova, which proved that sometimes the heavens do change. The newly invented telescope also revealed "imperfections" in celestial bodies: the sun was shown with sunspots, and the Moon has many features such as craters and mountain ranges. If the heavens were not as perfect as originally considered, then the idea that orbits are not perfect circles was not so questionable. Galileo also discovered the Galilean moons of Jupiter, celestial bodies orbiting another planet, and the phases of Venus. The existence of the Galilean moons refuted the common argument that the Moon would not stay with a moving Earth. As for the stellar parallax, Galileo could not prove that the stars were more distant than estimated, but got strong evidence suggesting it: a closer look at the Milky Way revealed that it is composed of several stars.
Although those discoveries proved that Earth was not located at the center of everything, they did not completely prove that it spins around the Sun; this fact was fully confirmed when the stellar parallax was measured in detail and with stellar aberration. However, the idea generated such controversy that Galileo was summoned by the Inquisition and forced to recant his findings. Galileo, who was 70 at the time and probably fearing that his life would be at stake, did as ordered. It is said that Galileo muttered "Eppur si muove" (Italian for "And yet it moves"), but most historians doubt it, given the possible consequences Galileo would have faced if heard.
Despite the trial, by 1630 the model of Kepler and the clarifications of Galileo were unanimously accepted. However, although it was accepted that planets moved in ellipses, it was not clear why they did so. The reason was finally explained by Sir Isaac Newton in his book Philosophiæ Naturalis Principia Mathematica, which described the three laws of motion. This book also introduced the law of universal gravitation, and explains all motions in the universe. It also uses maths to explain that Kepler's laws of planetary motion are a natural consequence of the laws of gravitation and motion. With this, the geocentric model was completely discarded.
The Copernican revolution, the time between Copernicus and Newton, was almost 150 years and changed science forever. It changed the view of the universe and the place of Earth and humankind in it, shifting from a central position to just a world like many others. It also changed the way science works. Previous academics were willing to give leeway to mistakes and errors of measurement, which were strictly less tolerated by the new generations. There was also a stronger emphasis to understand not only how nature works, but also why it works that way and not another. Mere guesses like atomism or aesthetic preferences like heavenly perfection would not fly anymore. Any explanation and assumption was required to be proved before being accepted.
Although the dispute was not specifically about extraterrestrial life, the outcome kickstarted it. As there was a conflict between atomists and Aristotelians back in ancient Greece, and the Aristotelians were proved to be wrong, many assumed that this meant that atomists were right and that other worlds were just like Earth. However, the only fact about this that was found at this time was that the stars and the classical planets are not lights but celestial objects analogous to Earth, and that life in them may be plausible, if still unknown. The idea of extraterrestrial life, which was once a radical notion held by limited and specific people, became an accepted idea discussed in college classrooms. The change was also possible because of the changes in religious and philosophical thinking that took place at the time.
Besides that, there was much speculation. Galileo confused the lunar mares with seas. Kepler said that the Moon has an atmosphere and intelligent inhabitants, even writing a science fiction story about them. Dominican philosopher Giordano Bruno accepted the existence of extraterrestrial life, which became one of the charges leveled against him at the Inquisition, leading to his execution.
Modern times
The study of astronomy continued after Newton, and later technological devices and math models allowed to study objects that were undreamt of at the time. Although no actual extraterrestrial life has been found, either in the Solar System or elsewhere, science currently has a far greater understanding of the context of such life or lack thereof. Biology studies the nature of life, and chemistry and biochemistry the way it works. Chemistry and biochemistry also help to understand abiogenesis, the process by which life can be generated by non-living things, which is not yet completely understood. Physics in general and planetary science in particular help to understand the conditions at places other than Earth and how they can be more beneficial or harmful for life. All those sciences are collectively studied under the umbrella science of astrobiology.
Most knowledge of astronomy is relevant in some way for the discussion of extraterrestrial life, but there are three main tenets. One, that the universe is incredibly vast and old. Second, the elements that make up life on Earth are plentiful. Third, that the laws that rule matter are the same across the universe. As a result, it can be reasoned that there is nothing special about Earth, and that life on other worlds should be plausible.
Notes
References
Bibliography
Extraterrestrial life
History of astronomy
Obsolete scientific theories
Religion and science
Theological controversies | History of the extraterrestrial life debate | [
"Astronomy",
"Biology"
] | 3,375 | [
"Hypothetical life forms",
"History of astronomy",
"Extraterrestrial life",
"Astronomical controversies",
"Biological hypotheses"
] |
76,346,548 | https://en.wikipedia.org/wiki/Galileo%20Violini | Galileo Violini is a theoretical physicist and the director emeritus of the in Bogotá, Colombia. He is the recipient of the 2024 Joseph A. Burton Forum Award "for establishing programs in physics education and research in Latin America and the Caribbean that increased regional scientific capacity, for promoting international scientific cooperation across continents and regions of the world, and for creating the Centro Internacional de Física in Colombia."
His main area of interests are science education, science diplomacy, and synchrotron science. He is participating in the project to bring a synchrotron light source to the Greater Caribbean.
Education and career
Violini graduated from La Sapienza University in Rome, Italy, in 1965, and obtained the Italian Libera docenza in theoretical physics from Sapienza in 1971, where he later became a professor of algebra and mathematical methods of physics. He then became a professor of theoretical physics at the University of Calabria in 1987.
In 1985 he founded the International Center for Physics of Bogotá (, CIF), in Colombia, modeled on the International Center for Theoretical Physics, where he is a director emeritus.
Awards and honors
2023 John Wheatley Award of the American Physical Society
2023 World Academy of Art and Science Fellow
Honorary member of the Colombian Academy of Exact, Physical and Natural Sciences
Outstanding Salvadorean Recognition from the Government of El Salvador
2016 Abdus Salam Spirit Award of the International Center for Theoretical Physics
UNESCO Representative to Islamic Republic of Iran
References
Sapienza University of Rome alumni
Theoretical physicists
Year of birth missing (living people)
Living people
Fellows of the American Physical Society | Galileo Violini | [
"Physics"
] | 320 | [
"Theoretical physics",
"Theoretical physicists"
] |
76,346,550 | https://en.wikipedia.org/wiki/Conservation%20genomics | Conservation Genomics is the use of genomic study to aide in the preservation and viability of different and diverse organisms and populations. Genomics can be utilized in order to classify or argue diversity, hybridization, and history as well as identity different and similar species. Genomics can evaluate how these measures relate to effective population size as well as other ideas under the umbrella of conservation genetics, and overall biological conservation. Genomic analysis can evaluate the extent to which alleles at certain loci interact with one and other to display nuanced ways which the genome may be intertwined.
Genetic diversity
Genetic diversity is a measure of the number of different alleles or combinations of alleles present in a population. This may be measured by the amount of heterozygosity measured compared to the expected amount of heterozygosity predicted by Hardy-Weinberg Equilibrium. Evaluating genetic diversity in the genomes of populations can inform us about levels of biodiversity and allele frequencies. Genetics play a large role in the extinction of species and understanding how certain alleles accumulate and interact at the genome level is crucial to the preservation of those species.
Heterozygosity
One of the most important measures of genomic health is the ratio of expected heterozygosity to measured heterozygosity. Generally, an individual or species with more heterozygous alleles have a higher chance of survival. This is known as heterosis. Low levels of heterozygosity is a sign of possible concern for a species or organism. Evaluating the genomes of organisms that exist in an endangered species or population segment can provide insight to the severity of their endangerment. This method can be used to classify and rank species as well.
Linkage disequilibrium
Linkage disequilibrium is a concept that defines the non-random association between two alleles at different loci in the genome. Measures of linkage disequilibrium are useful tools for gene and genome mapping. A linkage between two genes may be due to their positions relative to each other in the genome or it may be due to selection acting to favor certain combinations of alleles. On a genomic scale, linkage disequilibrium plays a large analytical role. The term linkage disequilibrium concedes that there may also be a disruption or lack of linkage between two alleles. Any sort of deviation from the expected linkage between two alleles is considered linkage disequilibrium. In the age of genetic analysis in the use of conservation, understanding how alleles interact with each other is imperative to understanding how genomic diversity, and conservation of such, can be aided.
Applications
Genomics and genomic analysis provide a bigger picture explanation of aggregate smaller genetic evaluations. Different relationships and reasoning can be drawn from the data presented by genomics than compared to that data that can be drawn from genetics. Genomics is beginning its use in the field of invasive species where it is thought that understanding how genomes drive invasive processes can help better protect native species from their devastating effects. These studies are aimed at tackling the major issue of habitat damage and disrupted ecosystems that invasive species have caused.
Under historical contexts, understanding genomic analysis can teach us much about patterns and effects of natural processes. Historical genomic evaluations have been performed on animals like Hominids, and even diseases like Multiple Sclerosis and the Black Death in order to determine their origins and evolutionary histories. In the case of diseases this information is often used in eradication efforts, as it would be used with invasive species. However, this data can be used in the preservation of species as well. Understanding the history of the genomics in a population is an important step in making decisions about how to correctly interpret and apply genomic analysis for conservation today.
In conservational contexts specifically, genomics can be used to research and understand how the relationships amongst the factors listed above affect an organism's fitness. The study of organisms through a genomic lens can lead to knowledge about their history that can be applied today.
Hybridization
Hybridization practices, as they become a larger player in conservation may be impacted by genomic research. Hybridization can create entirely new allelic relationships and disequilibria. Understanding these factors is important in the interests of effective conservation efforts. Furthermore, studying these new relationships in hybrids can continue to provide insight in the efforts to conserve species. Hybridization still has many critics and has been shown to cause reduced fitness amongst natural populations. There are still many questions about the consequences of hybridization on evolution and genetic health of species. Genomic studies may help to draw conclusions about new allelic relationships and how they may effect the outcomes for those species.
Current landscape
The current landscape of conservation genomics is still in its infancy. New ways to apply and understand genomics for the use of conservation are arising, and there is much thought that the understanding of gene interactions plays an important role in conservation. Currently, despite genomics being valuable to the conservation sphere, there is not enough of a connection between the researchers who study it and those with the means to apply it.
References
Wikipedia Student Program
Conservation biology
Genomics | Conservation genomics | [
"Biology"
] | 1,055 | [
"Conservation biology"
] |
76,347,341 | https://en.wikipedia.org/wiki/Temporary%20Cyber%20Operations%20Act | The Temporary Cyber Operations Act () is proposed Dutch legislation that will relax the restrictions on data interception and surveillance in the Intelligence and Security Services Act. It is intended to be used to defend against cyberattacks by other countries.
It was adopted by the Dutch House of Representatives in October 2023. The law was accepted by the Dutch Senate in March 2024.
References
Proposed laws
Computer law
Dutch legislation | Temporary Cyber Operations Act | [
"Technology"
] | 82 | [
"Computer law",
"Computing and society"
] |
76,347,437 | https://en.wikipedia.org/wiki/Cyclamin | Cyclamin is an organic compound that has been used by the pharmaceutical industry as an ingredient for nasal sprays.
History
Research on the cytotoxic and anticlastogenic activities of the cyclamen genus has been limited. In the 1950s and 1960s little research was done on the toxic saponin cyclamin, but no further investigation has recently been performed. Cyclamin, a triterpenoid pentasaccharidic saponin, has previously been extracted from different cyclamen species, including Cyclamen mirabile, Cyclamen trocopteranthum, Cyclamen libanoticum and Cylamen persicum.
Available forms
Cyclamin can be extracted from cyclamen plants such as the species mirabile and trocopteranthum. Cyclamen are known houseplants; this raises concerns about the awareness of the toxicity of this flower. The compound cyclamin belongs to the family of triterpene saponins, which are derived from the saponin structure. Triterpenoid compounds contain one or more sugar moieties attached to triterpenoid aglycones. The large diversity of structures causes saponins to exhibit a wide range of biological and pharmacological properties. In China, cyclamin has been used as a traditional medicine for years. Cyclamen has been used against menstrual disorders, digestive disorders, and anxiety in women. However, this is only the case for the leaves, the roots of the plants are known to be harmful if ingested. In these roots, cyclamin is found, as well as in the bulbs. Therefore, cyclamin is suspected to be the compound which causes the toxicity of these roots and bulbs in cyclamen plants.
Structure and Reactivity
As can be seen in Figure 1, cyclamin consists of a hydrophilic part with five connected saccharide groups. The second part of the cyclamin molecule consists of a non-polar, sterol-like backbone. These two different parts make that cyclamin molecules, and saponins in general, are highly amphipathic compounds. However, the exact mechanism of action of cyclamin has not been extensively researched. The structure-activity relationship (SAR) of cyclamin is not yet known.
The amphipathic nature of cyclamin makes the compound permeable through the membrane. The carbohydrate part of saponins is water-soluble, making them surface-active. Cyclamin is known as a white opaque substance obtained in solid form that absorbs up to 45% water. Upon absorption of water, it becomes a transparent substance. Furthermore, it is soluble in alcohol and turns brown when exposed to light. Saponins overall are known to be soluble in polar solvents. Except for alcohol and water, cyclamin has not been further tested. When dissolved in water, it produces foam by frothing test and upon heating it has the unique property of coagulation. Concentrated sulfuric acid colours cyclamin in purple red, which disappears with water addition.
Mechanism of action
Not much is known about the mechanism of action of cyclamin. However, a study proposed possible mechanisms of action based on their experimental results. Firstly, cyclamin might activate the proteins caspase-3, caspase-8 and caspase-9. Caspases are proteins that can induce apoptosis when being activated.
Secondly, cyclamin could be responsible for increasing the expression levels of the cyclin-dependent kinase 2 and the cell division cycle 25 homolog A. This can lead to increased DNA synthesis and cell proliferation and an increase in signal transduction pathways.
Thirdly, cyclamin could increase the ratio of Bax/B-cell lymphoma 2 expression. This would favour apoptosis to take place.
Another property that was found is that cyclamin increases the permeability of Bel-7402 cells. This might be the reason why cyclamin enhances the effect of some chemotherapeutical drugs.
Indications and symptoms
Cyclamin is an irritant compound that causes gastroenteritis, bloody stools, dizziness, seizures and even death by asphyxiation. Studied by many physiologists, cyclamin was viewed merely as a local irritant. However, considering the toxic effects of cyclamin, this a misconception. The roots and bulbs of cyclamen plants containing cyclamin are known to cause severe diarrhea, nausea, vomiting and even death if eaten raw.
Adverse and side effects
As cyclamin is not yet used as pharmaceutical drug such as for chemotherapy, no side effects were yet determined.
Applications
Cyclamin is used as an ingredient for a nasal spray to reduce the tension of the wall and induce secretion of mucus. Furthermore, due to its toxic effects on different (cancer) cell types, cyclamin might be considered for use as chemotherapeutic drug. However, more research first has to be done to reduce its toxicity on normal human cells.
Toxicological data
In a study, cyclamin was tested regarding its toxicity against several types of cancer cells: SK-BR-3, HT-29, HepG2/3A, NCI-H1299, BXPC-3, 22RV1 but also on its toxicity against human normal fibroblasts DMEM, which are not cancer cells. The results showed that cyclamin induced a significant increase of micronucleated cells after it was activated through metabolism. This means that heritable chromosome mutations could occur in these cells. This result was observed in all cell types that were analysed in this study, therefore including the fibroblasts. The toxicity was indicated by the IC50 value which gives the concentration of the compound at which it causes 50% of its inhibitory effect e.g. on enzymes in cells. The IC50 values of cyclamin were very similar across the different cell types, ranging from 0.32μM – 0.84μM, with the lowest IC50 value in the human normal fibroblasts DMEM cells, which indicates unspecific toxicity of cyclamin across different cell types (Table 1).
This indicates that cyclamin is more toxic to the human fibroblasts compared to its toxicity against cancer cell lines. Compared to the chemotherapeutic drug mitomycin C, which has IC50 values ranging from 0.45μM-20.20μM in the cancer cell lines, cyclamin was up to 50 times more toxic for certain cell types when comparing the IC50 values (Table 1).
The antioxidant activity of cyclamin was also determined. Cyclamin had an EC50 value of 0.96mM which indicates low antioxidant activity compared to reference compounds catechin (EC50 = 0.009 mM) and ascorbic acid (EC50 = 0.014 mM). The EC50 value represents the potency of a compound by stating the half-maximum concentration of the compound with regards to its concentration where it causes maximum response or effect. Furthermore, it seemed that cyclamin did not have an anticlastogenic effect in the tested cell lines.
Another study found that cyclamin was less toxic to human colorectal cancer cells, from that type HTC 166 and HT-29, compared to the chemotherapeutical drug paclitaxel. This could be concluded from the results that cyclamin had higher IC50 values compared to paclitaxel (Table 2).
To conclude, cyclamin shows broad toxicity against several cancer cell types, which would make it a promising drug to be used in that respect. However, its toxicity against normal human cells should be investigated further before using it as basis for chemotherapeutic drug to reduce unwanted side effects. For instance, cyclamin has been reported to selectively inhibit the proliferation of liver cancer cells. It is suspected to be related to molecular mechanisms increasing cell membrane permeabilization via targeting cholesterol. With this, it consequently targets the ligand-independent activation of Fas signalling pathway. Only after further investigation it can be decided if cyclamin is suitable for such a medical use.
Effects on animals
Cyclamin has not been thoroughly investigated in terms of its effects on animals, given it is not a widely known compound. However, the effects of Cyclamin on the snail Biomphalaria glabrata (Say) in terms of molluscicidal activity were researched. The lowest concentration showing 100% mortality to snails was 21 mg/l. Beside cyclamin its effect on these snails, no further data is known about its effect on animals.
References
Organic compounds | Cyclamin | [
"Chemistry"
] | 1,881 | [
"Organic compounds"
] |
76,349,275 | https://en.wikipedia.org/wiki/SPACEMAP | SPACEMAP (Korean: 스페이스맵) is a South Korean satellite orbit optimization and satellite communications company headquartered in Seoul, South Korea. The company was founded in 2021 by CEO, Douglas Deok-Soo Kim, as an offshoot of Hanyang University. It was funded by the Leader Research grant from the National Research Foundation of Korea with the goal of capitalizing on the growing space industry.
History
Kim initially began research into Voronoi diagrams at the University of Michigan. He met with Dr. Misoon Ma, former director of the Asia Division of the U.S. Air Force Office of Scientific Research (AFOSR) and was recruited to work with the U.S. Air force, using Voronoi diagrams for a satellite collision prevention program. After his work with the U.S. Air Force, Kim founded SPACEMAP Inc in September 2021. In 2023, the company was selected by Korea's Tech Incubator Program for Startups (TIPS) to be funded up to 17 billion KRW (approx. 13 million USD) in 3 years.
Technology
The services provided by SPACEMAP are based on using dynamic Voronoi diagrams to predict satellite orbits with the aim of enhancing space mission safety and efficiency. For complex problems involving many moving points, Voronoi diagrams maintain a near-constant computation time regardless of the number of points involved. By utilizing Voronoi diagrams and artificial intelligence, the software can easily determine the number of neighboring satellites surrounding a specific satellite and calculate the distances between them, thereby predicting the probability of a collision. SPACEMAP claims their method to be superior in computational time and memory efficiency, compared to the previously established three-filter method.
Products
SPACEMAP offers satellite products and services including the following:
AstroOne, a conjunction assessment, and optimal collision avoidance service for all space vehicles in both orbital and non-orbital motions.
AstroOrca, providing data transmission for satellites in multiple orbits, launch optimization, shuttle logistics for space gas stations, and Active Debris Removal (ADR) itinerary.
AstroLibrary, a library of RESTful APIs to access the C++ implementation of SPACEMAP's Voronoi diagram algorithms wrapped in a Python interface.
It also provides real-time tracking of the North Korean reconnaissance satellite, Malligyong-1.
References
External links
Platform website
Aerospace companies of South Korea
Technology companies established in 2021
Telecommunications
Hanyang University
2021 establishments in South Korea | SPACEMAP | [
"Technology"
] | 508 | [
"Information and communications technology",
"Telecommunications"
] |
76,349,782 | https://en.wikipedia.org/wiki/Lophelia%20reef | Lophelia reef (also known by its Wakashan name q̓áuc̓íwísuxv) is a coral reef that lies some 200 m underwater in Finlayson Channel in British Columbia, Canada. It is Canada's only known living coral reef, and the Pacific Ocean's northernmost known coral reef. It was discovered in the early 2020s after two local First Nations, the Kitasoo Xai'xais and the Heiltsuk, who "knew something was there," guided deepsea ecologist Cherisse Du Preez to the waters in which the coral ecosystem lives.
Canada's Fisheries Department has closed the area over the coral reef to all commercial and recreational bottom-contact and mid-water trawl fisheries. This is, according to the Department, based on a significant scientific discovery at the small yet globally unique reef, which is highly susceptible to damage from fishing gear.
The reef's site is now being assessed for the possibility of establishing there a Parks Canada National Marine Conservation Area.
References
Coral reefs
Central Coast of British Columbia | Lophelia reef | [
"Biology"
] | 217 | [
"Biogeomorphology",
"Coral reefs"
] |
76,350,521 | https://en.wikipedia.org/wiki/Daniel%20Allen%20Cohen | Daniel Allen Cohen is a Los Angeles-based multi-media artist best known for his platform, This is Addictive, which highlights adult cravings and material obsessions using imagery often associated with childhood nostalgia.
His series, Periodic Table of Drugs, parodies the format of the scientific periodic table but instead of cataloguing natural elements, Cohen catalogues a variety of narcotics. Cohen has shown his work at art fairs including SCOPE Art Show in Miami and the L.A. Art Show. In 2021, Cohen released his first non-fungible token art on Nifty Gateway's digital marketplace.
Work
Made from a variety of materials, including: wood, acrylic paint, metal, graphic design and digital alterations, Cohen's work satirizes consumer habits associated with youth culture in Western society. Incorporating substances, such as drugs, chocolate and diamonds, that are associated with decadence and often abused, Cohen is able to address the glamorization of addiction.
Score (2015)
In this series, Cohen comments on the increase of drug use, and ease of its availability, in the United States. Using the format of a nutrition label that lists ingredients in packaged food, he lists the effects of recreational drugs. In addition to creating these labels for actual drugs, Cohen invents drugs, like "Insta-Fame" pills and "Poor & Suffering Relief" pills.
Precious Bars (2016)
In 2016, Cohen released his Precious Bars series where he fabricated stacks of money and gold bars wrapped in the packaging of branded chocolate bars that were altered slightly. The iconic Mr. Goodbar, in Cohen's version, was changed to "Mr. Goldbar."
Periodic Table of Drugs (2017)
In this ongoing series, Cohen parodies the Periodic Table of Elements which outlines life-sustaining elements like Hydrogen, Carbon, Nitrogen and Oxygen. By featuring recreational drugs instead of chemical elements, Cohen illustrates the irony surrounding which substances are valued in contemporary society.
References
Living people
Multimedia artists
American artists
Contemporary art
Year of birth missing (living people) | Daniel Allen Cohen | [
"Technology"
] | 414 | [] |
76,350,802 | https://en.wikipedia.org/wiki/Pear%20switch | A pear switch is a particular type of electrical switch that usually has the appearance of a small pear. Its operation is very simple, with a button that, depending on the type, is pressed to activate or deactivate a circuit or is simply pressed like a pushbutton, for example in photographic enlarger switches.
It is characterized by its form and function. Unlike conventional switches that are fixed to the wall, the pear switch is suspended from the cable. By pressing the pear, the electrical contacts close the circuit. Its most common use is for hanging lamps, bed headboards, bedside tables, or generally in situations where you do not want to mount the switch on the wall.
Description
It is pear-shaped, oval or spherical, made of wood or plastic, which is connected to a mechanism that has a spring with an electrical contact. It is an automatic mechanism with a spring, similar to a push button but taking into account that there is a model that is bistable and returns the switch to its default position after pressing twice, changing the initial condition of the electrical circuit or restaurant, connecting or blocking the circulation of current in said electrical circuit.
Models
There are two kinds:
Switch/commutator: similar to a push button but it is a model that is bistable and returns the switch to its default position after pressing twice, changes the initial condition of the circuit or restores it and keeps the circuit electrically connected to maintain the electrical state current. In all cases, pressing the button again returns it to its initial position. (Examples: bed head switches, bedside lamp switches, photographic enlarger switches)
Pushbutton - is a momentary or latching switch that causes a temporary change in the state of an electrical circuit only while the switch is physically actuated . It allows electricity to flow between its two contacts when held. When the button is released, the circuit opens. This type of switch is also known as a normally open (NO) switch. Examples: bell at the head of the bed in old houses.
References
Bibliography
External links
Electrical engineering | Pear switch | [
"Engineering"
] | 417 | [
"Electrical engineering"
] |
76,351,908 | https://en.wikipedia.org/wiki/K252b | K252b is an ectoprotein kinase inhibitor, which is involved in the abolishment of the effects of nerve growth factors on PC12 cell and peripheral neuron system (PNS) neurons. When it is present in very low concentrations, it prolongs the survivorship of hippocampal, septal and cortical neurons deprived of glucose.
K252b is related to K252a and staurosporine, which are low-molecular-weight alkaloids. Staurosporine was discovered in 1977 while screening for microbial alkaloids using chemical detection methods. K252 was discovered in 1986 as a related natural indolocarbazole product. In 2007, K252b was found to have an inhibitory effect on mycobacterial protein kinase PknB. This is a receptor-like transmembrane protein. The PknB gene can be found in all known mycobacterial genomes. Staurosporine and K252a have inhibitory effects on the growth of Mycobacterium tuberculosis, but K252b failed to inhibit bacterial growth.
Metabolism
The metabolism of K252b, a complex organic molecule, is caused by interactions between the molecule and various metabolic pathways in different living organisms, microorganisms and animals are among these organisms.
Uses
In influencing NGF and neurite outgrowth
K252b controls neurite formation by inhibiting Nerve Growth Factor(NGF)-induced neurite outgrowth of PC12 cells. This inhibition is dose-dependent with higher concentrations of K252b leading to more NGF-induced neurite outgrowth inhibition. The exact mechanism of K252b inhibition of NGF-induced neurite outgrowth is still largely unknown.
In synapse formation
Continuous application of K252b also dose-dependently inhibits the formation of synapses in the cultured cortical neurons of rat brains, with higher doses resulting in higher inhibition. K252b does this by suppressing phosphorylation of the extracellular domains of proteins, mainly the microtubule-associated protein (MAP) 1B is sensitive to the inhibiting effects of K252b. Additionally, K252b application causes a significant drop in the frequency of synchronous firing of cultured cortical neurons of rats.
In immune response processes
K252b inhibits the immune response of mast cells and human basophil cells in several ways. Inhibition of the mast cell and human basophil immune response by involvement of ectokinase K252b in IgE-receptor mediated signaling has been speculated to function as a suppressor of acute allergic reactions. K252b's inhibition is dose-dependent, with higher concentrations of K252b resulting in more inhibition. The role of K252b in suppressing the immune response lies mainly in preventing cytosolic Ca2+ increase and preventing degranulation and histamine release in mast cells and human basophils.
Effects of K252b on cytosolic Ca2+ concentrations
K252b inhibits Ca2+ cytosolic concentration increases. K252b does this by inhibiting the Ca2+ influx from extracellular fluid and Ca2+ release from intracellular storage, therefore preventing the increase of the Ca2+ cytosolic concentration, which is an essential step in the process of activation of the immune response of mast cells and human basophil cells.
Effects on degranulation and histamine release of mast cells and human basophils
K252b inhibits basophil and mast-cell histamine release induced by both Ag and BA3. Additionally, K252b dose-dependently inhibits Ag induced β-hexosaminidase release. K252b also inhibits IgE receptor-mediated degranulation of mast cells, in this process K252b acts at a very early stage of IgE receptor-mediated stimulation, which according to Teshima et al. means that the target for K252b is likely an early signaling molecule active in the process of IgE receptor mediation. K252b also suppresses the IgE receptor-mediated histamine release and to a lower extent also 150 nM TPA mediated histamine release in mast cells and human basophil cells. Degranulation is, like increase in the cytosolic Ca2+ concentration, an essential step in the activation of the immune response of mast cells and human basophil cells.
Efficacy
In general
K252b has been shown to have a higher efficacy at higher doses, making its inhibiting processes dose dependent. Since K252b does not permeate the cell membrane of the cells it acts upon, due to its hydrophilic nature, K252b generally has a low cytotoxicity and leaves less cytotoxic damage than its membrane-permeating analogs like K252a.
In the process of NGF-induced neurite outgrowth inhibition
K252b has been shown to entirely inhibit NGF-induced neurite outgrowth at concentrations of 300 nM, while K252b concentrations of 100 nM or less result in a partial inhibition.
Toxicology data
The CC50 was reported to be less than 40 μM against murine macrophage J774A.1 measured by AlamarBlue assay.
Structure, reactivity, and synthesis
K252b is a large molecule which falls into the indolocarbozole category. K252b looks very much like another indolocarbazole: K252a. The difference between these 2 is that K252b possesses a carboxylic acid group where K252a has an ester instead. This difference makes K252b a lot more hydrophobic than K252a, the partition coefficient for K252b is 4.4:1 (org:aq) and 15.6:1 for K252a2. This difference in hydrophilicity has an impact on the uptake and concentration of K252b into cells. K252b is taken up reversibly by PC12 and Sf9 cells, whereas K252a is taken up irreversibly at a higher concentration.
One path to synthesize K252b, would be to synthesize K252a first and then react K252a with a strong base. K252a has been synthesized in many papers, there is no known route to directly synthesize K252b yet.
Molecular mechanism of action
K252b inhibits tyrosine kinase receptors and the long-term trophic effects of NT-3 and BDNF at concentrations above 100 nM. At concentrations under 100 nM it stimulates the trophic effects of NT-3.
See also
K252a
References
Protein kinase inhibitors
Heterocyclic compounds with 7 or more rings
Alpha hydroxy acids
Carboxylic acids
Nitrogen heterocycles
Oxygen heterocycles
Indoles | K252b | [
"Chemistry"
] | 1,491 | [
"Carboxylic acids",
"Functional groups"
] |
76,352,974 | https://en.wikipedia.org/wiki/Tris%28cyclooctatetraene%29triiron | Tris(cyclooctatetraene)triiron or Fe3(COT)3, also referred to as the Lavallo-Grubbs compound (after its discoverers) is an organoiron compound with the formula Fe3(C8H8)3. It is a pyrophoric, black crystalline solid, which is insoluble in common organic solvents.The compound represents a rare example of a hydrocarbon analogue of the well-known Triiron dodecacarbonyl (Fe3(CO)12), originally prepared by Dewar and Jones in the early 20th century.
Preparation
Lavello and Grubbs discovered the compound unexpectedly when trying to prepare noncarbonyl, low coordinate, Fe(0) complexes of N-heterocyclic carbenes (NHCs). They found that reactions of Fe(COT)2 and the NHC, 1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene (SIMes), produced tetrametallic, Fe(I)-Fe(0) mixed valent NHC-COT complexes. In an attempt to characterize intermediates of the unusual transformation, they employed the more sterically hindered NHC, 1,3-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazol-2-ylidene (SIPr) (with Dipp substituents).In benzene, the Dipp substituted NHC reacts with Fe(COT)2 to produce large black rhomboidal crystals of tris(cyclooctatetraene)triiron over 24 h at room temperature. Notably, the reaction was found to occur with catalytic amounts of NHC (10 mol%) yielding 67% of Fe3(COT)3 after 24 h (turn over number=9.5). The synthesis is optimized when the reaction is conducted at 45 °C, yielding 95% conversion to the tris(cyclooctatetraene)triiron cluster. They also highlighted that heating Fe(COT)2 in benzene without any NHC to 100 °C for 24 h forms trace amounts of Fe3(COT)3, but also large amounts of iron metal. Unsurprisingly, elemental analysis of the cluster affirms a 1:1 Fe:COT ratio.
The formation of Fe3(COT)3 from Fe(COT)2 has been calculated to be slightly exothermic(15 kcal/mol).
Other NHCs lead to other unique mixed NHC-COT low valent iron complexes. Lavallo and Grubbs rationalize the transformation by emphasizing the capacity of NHCs to catalytically induce the formation of metal-metal bonds, where the steric hindrance of the NHC is essential, in particular, for the lability of the NHC (in coordination and dissociation) in the cycle. The bulky NHC is proposed to prevent reduction of COT by a bimetallic [(L)Fe2(COT)2] intermediate, where steric constraints block the bonding hapticity required to ligate a reduced form of COT. Another possibility put forward is that reduction of COT occurs only following coordination by a second carbene in the case of SIMes during the catalytic cycle. The sterically hindered NHC prevents such a transformation from occurring.
Electronic structure and bonding
The discoverers were reluctant to assert an oxidation state of the iron centers in the compound, instead deferring the details of the electronic structure to computational studies.
The crystal structure reveals that the three iron centers arrange in an equilateral triangle (nearly ideal; Fe1 = 59.67°, Fe2 = 60.15°, and Fe3 = 60.18°) The corresponding bond lengths are similar to one another, (Fe1–Fe2 = 2.829 Å, Fe1–Fe3 = 2.815 Å, and Fe2–Fe3 = 2.830 Å), and reflective of Fe-Fe single bonds. As a trinuclear cluster, it would be thought to have a stable 48-electron closed-shell configuration (24 electrons from the three iron atoms and 24 electrons from the three COT rings).
In the original depiction, each COT ligand acts as an η3 and η5 donor, and thus, some degree of π-allylic and pentadienyl bonding modes can be inferred – though the degree of metal-to-ligand electron transfer is uncertain. Computational models suggest the binding mode to lie between η3 and η5, as small shifts in geometry make each mode effectively equivalent (see section on fluxional behavior). Furthermore, DFT calculations with the BLYP functional using a TZP basis set for iron and DZP for carbon and hydrogen estimate a Hirshfeld charge of 0.08 on the iron centers (and Voronoi deformation density of 0.00). Interestingly, all of the bond orders of the C-C ring lie between 1.26 and 1.33, sharply contrasting the discrete single and double bonds of free cyclooctatetraene, or COT complexes with non-bound olefins.
Doubly reduced COT (dianion) is known to adopt a planar (aromatic) conformation to metal centers, which is not observed in Fe3(COT)3. However, arguments also exist that such conformations are more related to binding efficiency than aromaticity.
In computational studies (BP86), when Fe3(C8H8)3 is optimized as a singlet (gas phase), the iron centers are arranged in an ideal equilateral triangle, as experimentally observed in the crystal structure. In such an electronic configuration, each iron atom achieves an 18-electron configuration through pseudo η5 and η3 coordination to alternating COT ligands. However, if the compound is optimized as a triplet structure, the iron centers instead are a scalene triangle, featuring significant Jahn-Teller distortions.
Additional NBO analysis of the singlet structure reveals Wiberg Bond Indices of 0.22 for the Fe-Fe bonds, closely reminiscent of that of D3h Fe3(CO)12 (0.18).
Fluxional behavior
The V conformation of COT has an angle at 135° and is thought to be highly stabilized via bonding with the iron atoms (in free COT, this conformation is disfavored by approximately 36 kcal/mol).
Fascinatingly, in benzene solution, 1H NMR reveals a single broadened resonance with a chemical shift at -3.15 ppm. This suggests that the cyclooctatetraene ligands are highly fluxional and some degree of paramagnetism.
COT is known to be a highly fluxional ligand in other compounds too, such compounds being deemed “ring-whizzers” (like the related (cyclooctatetraene)iron tricarbonyl).
The conformational fluxionality is supported by computational studies which show very low barriers to COT rotation (on the scale of 1.4 kcal/mol) and rocking (0.1 kcal/mol). The transformation from the C3h singlet conformation to the triplet C2v conformation have been calculated to be nearly isoenergetic, driving the possibility of the singlet state existing in equilibrium with the triplet state- an explanation for the observation of paramagnetic NMR resonances at ambient temperatures.
Reactivity and Applications
The compound is highly reactive and pyrophoric, self-igniting in air. The lack of reactivity studies may be in part sourced from its very low solubility in organic solvents. However, it may be able to find use as a specialized source of reactive low-valent iron.
Computational studies have estimated COT dissociation from Fe3(COT)3 to be 57 kcal/mol uphill, which would not be readily accessible at room temperature in solution.
With analogy to Fe3(CO)12, the compound could potentially be susceptible to Fe-Fe bond homolysis via photoexcitation.
Analogies to Related Compounds
At the time of discovery, it was the only homoleptic trimetallic non-carbonyl cluster featuring hydrocarbon ligands. An isolobal analogy can be made with the related Fe3(CO)10 (μ-CO)2 cluster first prepared by Jones and Dewar.
Alternatively, the compound could be compared to ferrocene. In this interpretation, each iron fragment bears an η3 allyl and η5 pentadienyl ligand as depicted. Under Green and Parkin's covalent bond classification method, this would yield LX and L2X respectively. Then additionally, the iron centers donate a pair of electrons into an adjacent empty iron orbital as an adduct (donor-acceptor pairs L and Z type), to overall yield ML3X4 (18 electrons). In fact, the bond orders in ferrocene and Fe3(COT)3 are reported to be very similar.
In fact, Fe3(CO)12 and the group 5 analogues, Ru3(CO)12 and Os3(CO)12 are also known to feature highly fluxional CO ligands in solution (and even in the solid state).
Hypoelectronic derivatives (M=Ti, Cr, V, Mn) of Fe3(C8H8)3 would be predicted to have metal multiple bonds. Some somewhat related compounds, notably, Ti2(C8H8)3 and Cr2(C8H8)3 have been experimentally isolated.
References
Organoiron compounds
Wikipedia Student Program
Cluster chemistry | Tris(cyclooctatetraene)triiron | [
"Chemistry"
] | 2,061 | [
"Cluster chemistry",
"Organometallic chemistry"
] |
76,352,984 | https://en.wikipedia.org/wiki/Symmetry%20aspects%20of%20M.%20C.%20Escher%27s%20periodic%20drawings | Symmetry aspects of M. C. Escher's periodic drawings is a book by crystallographer Caroline H. MacGillavry published for the International Union of Crystallography (IUCr) by Oosthoek in 1965. The book analyzes the symmetry of M. C. Escher's colored periodic drawings using the international crystallographic notation.
In 1959, MacGillavry met Escher. His work, the regular tiling of the plane, showed obvious links with the symmetry principles of crystallography. After seeking approval from the organisers (Joseph and Gabrielle Donnay), MacGillavry asked Escher to exhibit his lithographic works at the IUCr Congress in Cambridge, U.K. in 1960. The exhibition was a success, and as a consequence the IUCr commissioned MacGillavry to write the book under its auspices.
Structure and topics
The book has three chapters. In the first chapter, entitled Patterns with Classical Symmetry, the author introduces the concepts of motif, symmetry operations, lattice and unit cell, and uses these to analyze the symmetry of 13 of Escher's tiling designs.
In the second chapter, Patterns with Black-white Symmetry, the antisymmetry operation (indicated by a prime ') is introduced. The chapter analyzes 22 of Escher's design in terms of black-white symmetry and assigns each a symbol in the international notation describing its symmetries.
In the third chapter, Patterns with Polychromatic Symmetry, the analysis is extended to 7 of Escher's design possessing three or more colors. The book is printed in full color to facilitate the recognition of color symmetries in the images.
Audience
The publication of the book was sponsored by the IUCr and the original target audience was crystallography students learning the principles of symmetry, particularly color symmetry. In the introduction to the book the author states "Although the book is meant primarily for undergraduate students, I hope that many people who are simply amused and intrigued by Escher's designs will be interested to see how they illustrate the laws of symmetry".
Reception and influence
The reception of the book was positive. Robert M. Mengel in Scientific American wrote "[the author] has organized this unique and beautiful book from the corpus of marvelous spacefilling periodic drawings made over two decades by the artist Maurits C. Escher. Adding a few specially drawn for this work, Escher has here given us the classical crystal groups in the plane, and a good many more that exploit the latest extensions to color symmetry, foreseen by the artist before mathematicians had officially recognized and classified them."
F. I. G. Rawlins in Acta Crystallographica wrote "Under [the author's] sure guidance the reader is skilfully conducted through such regions of the theory of symmetry as are necessary for a tolerable grasp of the full significance of these patterns, several of them produced in full colour."
J. Bohm reviewed the book in Kristall Und Technik. Bohm acknowledged the special value of Escher's art as crystallographic teaching material. He praised the author for preparing the material in a detailed, crystallographically valid and didactically appealing way. Overall he stated that the book was a successful collaboration between the artist, author, publisher and the IUCr.
In 1976 an announcement in the IUCr's journals stated that the book was "extremely popular" and this had a necessitated a reprint in both the Netherlands and the U.S.A. In an obituary of the author it is stated that the publication of the book helped to popularise M. C. Escher's work in the U.S.A. MacGillavry's book inspired further work on the symmetry analysis of M. C. Escher's work, particularly by Doris Schattschneider in M. C. Escher: Visions of Symmetry.
Editions
First edition published for International Union of Crystallography by Oosthoek in 1965
Second edition published for International Union of Crystallography by Bohn, Scheltema & Holkema in 1976
Reprint edition with the title Fantasy & symmetry: the periodic drawings of M. C. Escher published by Harry N. Abrams in 1976
Third edition published by International Union of Crystallography in 2017
References
External links
'' at the Internet Archive
Symmetry
M. C. Escher
Mathematics books | Symmetry aspects of M. C. Escher's periodic drawings | [
"Physics",
"Mathematics"
] | 913 | [
"Geometry",
"Symmetry"
] |
76,354,159 | https://en.wikipedia.org/wiki/Tanja%20Zimmermann | Tanja Zimmermann (born August 10, 1967) is a Swiss materials scientist and wood researcher, professor of materials science and technology at the School of Engineering at EPFL and the Department of Materials at ETH Zurich, who is an elected fellow (FIAWS) of the International Academy of Wood Science.
Since 2022, Zimmermann serves as the director of the Swiss Federal Laboratories for Materials Science and Technology (EMPA) in Switzerland.
Biography
Zimmermann was born in 1967 in Hamburg.
She pursued her studies in wood science and technology at the University of Hamburg in the years 1987–1992. She completed her MSc at EMPA, working upon the analysis and characterization of the surfaces of spruce wood. In the years 1994-2000, she worked as a research scientist at the wood department of Empa. During the period 2002-2006, she did her PhD studies on cellulose-based materials at Empa, in collaboration with the University of Hamburg.
Between 2010 and 2022, she served as the head of the Functional Materials Department, serving also as a co-head at the Research Focus Area Sustainable Built Environment at EMPA. Her research interests are focused on functionalised wood, cellulose-based materials with upgraded properties, and in addition, on adhesives and biodegradable products for sensor and energy uses.
She possesses over 100 publications in scientific journals, in the research area of wood science and technology. She has more than 8,000 international citations at Google Scholar.
In cooperation with her team members, Zimmermann has won several innovation awards, like the "Swiss Green Economy Symposium Award," the "Cadre d’Or" from Baukader Schweiz for the achievements in wood construction, and an award for the best innovative environmental technology at the Pollutec exhibition in Lyon.
Recognition
Fellowship, The International Academy of Wood Science (2010)
SDG Award 2020, Swiss Green Economy (2020)
Elected director of EMPA (2022)
References
External links
Scopus
Swiss scientists
Fellows of the International Academy of Wood Science
University of Hamburg alumni
Academic staff of ETH Zurich
Wood scientists
Living people
1967 births | Tanja Zimmermann | [
"Materials_science"
] | 431 | [
"Wood sciences",
"Wood scientists"
] |
70,509,023 | https://en.wikipedia.org/wiki/Balance%20of%20angular%20momentum | The balance of angular momentum or Euler's second law in classical mechanics is a law of physics, stating that to alter the angular momentum of a body a torque must be applied to it.
An example of use is the playground merry-go-round in the picture. To put it in rotation it must be pushed. Technically one summons a torque that feeds angular momentum to the merry-go-round. The torque of frictional forces in the bearing and drag, however, make a resistive torque that will gradually lessen the angular momentum and eventually stop rotation.
The mathematical formulation states that the rate of change of angular momentum about a point , is equal to the sum of the external torques acting on that body about that point:
The point is a fixed point in an inertial system or the center of mass of the body. In the special case, when external torques vanish, it shows that the angular momentum is preserved. The d'Alembert force counteracting the change of angular momentum shows as a gyroscopic effect.
From the balance of angular momentum follows the equality of corresponding shear stresses or the symmetry of the Cauchy stress tensor. The same follows from the Boltzmann Axiom, according to which internal forces in a continuum are torque-free. Thus the balance of angular momentum, the symmetry of the Cauchy stress tensor, and the Boltzmann Axiom in continuum mechanics are related terms.
Especially in the theory of the spinning top the balance of angular momentum plays a crucial part. In continuum mechanics it serves to exactly determine the skew-symmetric part of the stress tensor.
The balance of angular momentum is, besides the Newtonian laws, a fundamental and independent principle and was introduced first by Swiss mathematician and physicist Leonhard Euler in 1775.
History
Swiss mathematician Jakob I Bernoulli applied the balance of angular momentum in 1703 – without explicitly formulating it – to find the center of oscillation of a pendulum, which he had already done in a first, somewhat incorrect manner in 1686. The balance of angular momentum thus preceded Newton's laws, which were first published in 1687.
In 1744, Euler was the first to use the principles of momentum and of angular momentum to state the equations of motion of a system. In 1750, in his treatise "Discovery of a new principle of mechanics" he published the Euler's equations of rigid body dynamics, which today are derived from the balance of angular momentum, which Euler, however, could deduce for the rigid body from Newton's second law. After studies on plane elastic continua, which are indispensable to the balance of the torques, Euler raised the balance of angular momentum to an independent principle for calculation of the movement of bodies in 1775.
In 1822, French mathematician Augustin-Louis Cauchy introduced the stress tensor whose symmetry in combination with the balance of linear momentum made sure the fulfillment of the balance of angular momentum in the general case of the deformable body. The interpretation of the balance of angular momentum was first noted by M. P. Saint-Guilhem in 1851.
Kinetics of rotation
Kinetics deals with states that are not in mechanical equilibrium. According to Newton's second law, an external force leads to a change in velocity (acceleration) of a body. Analogously an external torque means a change in angular velocity resulting in an angular acceleration. The inertia relating to rotation depends not only on the mass of a body but also on its spatial distribution. With a rigid body this is expressed by the moment of inertia. With a rotation around a fixed axis, the torque is proportional to the angular acceleration with the moment of inertia as proportionality factor. Here the moment of inertia is not only dependent on the position of the axis of rotation (see Steiner Theorem) but also on its direction. Should the above law be formulated more generally for any axis of rotation then the inertia tensor must be used.
With the two-dimensional special case, a torque only results in an acceleration or slowing down of a rotation. With the general three-dimensional case, however, it can also alter the direction of the axis (precession).
Formulations
In rigid body dynamics the balance of angular momentum leads to Euler's equations.
In continuum mechanics the balance of angular momentum leads to Cauchy's second law of motion, that states the symmetry of the Cauchy stress tensor. The Boltzmann Axiom has the same consequence.
Boltzmann Axiom
In 1905, Austrian physicist Ludwig Boltzmann pointed out that with reduction of a body into infinitesimally smaller volume elements, the inner reactions have to meet all static conditions for mechanical equilibrium. Cauchy's stress theorem handles the equilibrium in terms of force. For the analogous statement in terms of torque, German mathematician Georg Hamel coined the name Boltzmann Axiom.
This axiom is equivalent to the symmetry of the Cauchy stress tensor. For the resultants of the stresses do not exert a torque on the volume element, the resultant force must lead through the center of the volume element. The line of action of the inertia forces and the normal stress resultants σxx·dy and σyy·dx lead through the center of the volume element. In order that the shear stress resultants τxy·dy and τyx·dx lead through the center of the volume element
must hold. This is actually the statement of the equality of corresponding shear stresses in the xy plane.
Cosserat Continuum
In addition to the torque-free classical continuum with a symmetric stress tensor, cosserat continua (polar continua) that are not torque-free have also been defined. One application of such a continuum is the theory of shells. Cosserat continua are not only capable to transport a momentum flux but also an angular momentum flux. Therefore, there also may be sources of momentum and angular momentum inside the body. Here the Boltzmann Axiom does not apply and the stress tensor may be skew-symmetric.
If these fluxes are treated as usual in continuum mechanics, field equations arise in which the skew-symmetric part of the stress tensor has no energetic significance. The balance of angular momentum becomes independent of the balance of energy and is used to determine the skew-symmetric part of the stress tensor. American mathematician Clifford Truesdell saw in this the "true basic sense of Euler's second law".
Area rule
The area rule is a corollary of the angular momentum law in the form: The resulting moment is equal to the product of twice the mass and the time derivative of the areal velocity.
It refers to the ray to a point mass with mass m. This has the angular momentum with the velocity and the momentum
.
In the infinitesimal time dt the trajectory sweeps over a triangle whose content is , see image, areal velocity and cross product "×". This is how it turns out:
.
With Euler's second law this becomes:
.
The special case of plane, moment-free central force motion is treated by Kepler's second law, also known as the area rule.
References
Continuum mechanics
Equations of physics
Scientific observation | Balance of angular momentum | [
"Physics",
"Mathematics"
] | 1,486 | [
"Equations of physics",
"Continuum mechanics",
"Mathematical objects",
"Classical mechanics",
"Equations"
] |
70,509,308 | https://en.wikipedia.org/wiki/Karen%20Morse%20%28chemist%29 | Karen Dale Williams Morse is a inorganic chemist. She was president of Western Washington University from 1993 until 2008, and was named the Bowman Distinguished Professor in 2014. She is an elected fellow of the American Association for the Advancement of Science.
Education and career
Morse has a B.A. from Denison University (1962), and an M.S. and Ph.D. from the University of Michigan. During her Ph.D. she worked on Lewis acids. Morse joined the faculty of Utah State University in 1968 in the department of chemistry and biochemistry, and subsequently became the department head, the dean, and was named provost in 1989. In 1993 she moved to Western Washington University where she was president until 2008. In 2014, Morse was named the Bowman Distinguished Professor at Western Washington University.
Morse's early research centered on the production and properties of phosphines. She also worked on borohydrides, phosphite, metal-phosphorus compounds, aryl phosphines Morse also led the professional training committee at the American Chemical Society where she expanded on options for recognizing educators who teach chemistry at the undergraduate and high school level.
Selected publications
Awards and honors
Morse was elected a fellow of the American Association for the Advancement of Science in 1986. In 1997 she received the Garvan–Olin Medal for scientific accomplishments by a woman chemist from the American Chemical Society. In 2012 Western Washington University named the chemistry building the Karen W. Morse Hall in recognition of her. In 2021, Utah State University awarded her with an honorary doctorate.
References
Living people
Inorganic chemists
Utah State University faculty
Western Washington University faculty
Heads of universities and colleges in the United States
Fellows of the American Association for the Advancement of Science
Year of birth missing (living people)
Women heads of universities and colleges
21st-century American women scientists
20th-century American chemists
20th-century American women scientists
American women chemists
21st-century American chemists
Academics from Bellingham, Washington
Scientists from Bellingham, Washington | Karen Morse (chemist) | [
"Chemistry"
] | 401 | [
"Inorganic chemists"
] |
70,509,901 | https://en.wikipedia.org/wiki/V471%20Tauri | V471 Tauri (short V471 Tau) is an eclipsing variable star in the constellation of Taurus. The star has a visual magnitude of 9 which makes it impossible to see with the naked eye. It is around 155 light-years away from the Solar System, in the Hyades star cluster.
Physical properties
The V471 Tauri system has at least two members: a white dwarf star of spectral type D2; and a K-type main sequence star (K2 V), together a post-common envelope binary. There are variations in the timing of the eclipses that were once thought to be due to a third member of the system, proposed to be a brown dwarf, but a direct imaging search for this object with SPHERE resulted in a non-detection. The eclipse variations may be caused by the Applegate mechanism, or the third body may be a pair of smaller brown dwarfs, which would be too faint to have been detected. Later studies have found that the timing variations cannot be explained solely by additional components of the system; even if one or more brown dwarfs are present, the Applegate mechanism must also be a factor.
References
K-type main-sequence stars
White dwarfs
Eclipsing binaries
Taurus (constellation)
Tauri, V471
017962
Hyades (star cluster)
RS Canum Venaticorum variables | V471 Tauri | [
"Astronomy"
] | 284 | [
"Taurus (constellation)",
"Constellations"
] |
70,510,037 | https://en.wikipedia.org/wiki/Andreaea%20blyttii | Andreaea blyttii, also commonly known as Blytt's rock moss, is a moss belonging to the family Andreaeaceae, commonly known as rock moss, granite moss, or lantern moss because of this family's unique sporangium. It is part of the genus Andreaea which is known for forming dark brownish or reddish-black carpets in high elevations. This species was first described by Wilhelm Philippe Schimper in 1855.
Description
The shoots of A. blyttii vary in length. They are distinctively known for being small and dark red or black. They form tuffs and have acrocarpus growth. Depending on the frequency of desiccation, the branching pattern can vary from unbranched to irregularly branched. The number of leaves per shoot increases in dry environments. The stem walls are made up of pigmented cells and the stem lacks a conducting strand which is a character of the genus Andreaea. Rhizoids are attached at the base of the shoot. The spores are uniquely small in this species and grow into a thalloid protonema. The leaves of this species are known to vary in morphology. Leaf length and curvature, costa width and cell length are reduced in response to desiccation. Leaf curvature can be erect, falcate-secund, or curved. Larger more curved leaves with a smaller subula have been noted as a deviant morphology. Most leaves are erect and have a short and wide basal lamina with rectangular unistratose cells and a long subula also known as a limb with a costa spanning the entire length of the leaf. The costa is multistratose. This moss is closely related to Andreaea nivalis but A. blyttii lacks the denticulate leaf margins and very papillose upper cells of A. nivalis.
Habitat
Andreaea blyttii is usually found on rocks such as gneiss and granite. It also found in late to extremely late snow beds at low to high latitudes and elevations. It forms dense mats in mountain alpines where few other mosses can survive and is able to colonize sites of deglaciation. In Norway, it has commonly been observed growing in association with Hymenoloma crispulum and Schistidium pulchrum. A. blyttii grows better on non-calcareous rocks.
Distribution
Andreaea blyttii is distributed across higher elevations in Greenland, Iceland, Northern Europe, Northern Asia and across North America in California, Oregon, Washington, British Columbia, Alaska, Yukon, North West territories, Nunavut, Newfoundland and Labrador, and Quebec.
Reproduction
Andreaea blyttii can reproduce asexually and sexually. Asexual reproduction is through vegetative fragments. After touching A. blyttii, your hands can collect some of the fragments. The frequency of vegetative reproduction is recorded to be higher in moist environments but A. blyttii survive better in dry environments. Fragments need to be able to anchor to their substrate which is usually rock before getting washed away. Sexual reproduction occurs through sporic meiosis like in all bryophytes. A. blyttii is autoicous meaning its female and male reproductive structures are on separate branches but on the same shoot. The archegonium is borne at the tip of the shoot and is wrapped in perichaetial leaves which are differentiated from the rest of the leaves on the shoot. The sporophyte emerges from the archegonium. All members of Andreaeopsida lack a seta and instead have a gametophyte pseudopodium that attaches to the sporangium. The capsules of the sporangium lack peristome teeth and have 4 lines of moisture sensitive openings called lines of dehiscence. To release spores the capsule opens via the lines of dehiscence when dry giving the sporophyte a paper lantern appearance. These capsule openings allows for the spores to be released gradually. The spores of this species are characteristically small ranging from 13-15 μm.
References
Andreaeaceae
Lithophytes
Plants described in 1855
Near threatened biota of Europe | Andreaea blyttii | [
"Biology"
] | 858 | [
"Lithophytes",
"Plants"
] |
70,510,094 | https://en.wikipedia.org/wiki/G290.1-0.8 | G290.1-0.8 (also known as MSH 11-61A) is a supernova remnant in the constellation Carina. It is located in the Galactic plane of the galaxy in the Carina arm.
The supernova remnant has two bright spots opposite symmetric to each other on a symmetry axis running towards north west-south east direction. Theses bright spots are not homogeneous to the rest of the supernova remnant and had not reached ionization equilibrium yet.
This suggests that there might be a neutron star that has not been discovered yet. The rest of the supernova remnant originated from a high mass star that went supernova with a possible strong bipolar wind.
References
Carina (constellation)
Supernova remnants | G290.1-0.8 | [
"Astronomy"
] | 148 | [
"Carina (constellation)",
"Astronomy stubs",
"Constellations",
"Nebula stubs"
] |
70,511,345 | https://en.wikipedia.org/wiki/Eoseira | Eoseira is an extinct genus of diatoms belonging to the family Aulacoseiraceae and containing the single species Eoseira wilsonii. The species is dated to the Early Eocene Ypresian stage and has only been found at the type locality in east central British Columbia.
Distribution
Eoseira wilsonii was an algal bloom forming diatom during the Early Eocene Climatic Optimum and one of the major lake components the Horsefly Shales lake system. The Horsefly shales have not been radiometrically dated, but based on shared floral and faunal taxa found in the other Early Eocene, Ypresian age, Okanagan Highlands sites, Horsefly is assumed to be contemporaneous.
History and classification
Diatom fossils at Horsefly had been noted by Mark Wilson and Adrian Bogan (1994) who identified significant diatom volumes in the "summer varves" during study of a 6,375 year long stratigraphic section. Fossil material was studied subsequently by Alexander Wolfe and Mark Edlund (2005) with the type description of the species being published in the Canadian Journal of Earth Sciences. They designated three type specimens at the time of publication, the holotype "CANA 76143" and paratype "BCr; CANA 76144" which were both accessioned into the Canadian Museum of Nature at Ottawa, while the isotype was placed in the California Academy of Sciences Diatom Herbarium. Both the holotype and isotype were collected from the lower (H2) varve sequence exposed at the Horsefly mine locality. The paratype was collected at the nearby outcrops along the Black Creek Road. Wolfe and Edlund coined the specific epithet wilsonii as a patronym honoring Mark Wilson as recognition for his enormous work on western North American Eocene lake paleolimnology and paleoichthyology. They did not give an etymology for the genus name Eoseira.
E. wilsonii was placed into the family Aulacoseiraceae based on the numerous similarities to other members of the family, but placed into the monotypic new genus Eoseira due to a suite of distinctive features. Aulacoseiraceae is considered one of the first diatom families to transition from marine to freshwater habitats, sometime during the Cretaceous. The oldest genus of the family is Aulacoseira, from which Eoseira and other undescribed genera branched from in the Eocene, while a second diversification even took place in the Miocene resulting in the extinct genera Alveolophora, Miosira, and Pseudoaulacosira. E. wilsonii is suggested to be a sister branch to the aulacoseiroid lineages.
Description
Eoseira wilsonii grew valve frustules with a cylindrical cross-section when viewed from the end, and a rectangular outline when viewed from the side. The individual valves formed linked filaments, with many individual frustules connected end to end by an interlinking collar of spines that arise from the face-side junction. The spines on a valve are spoon-shaped with a narrow base widening to an ovoid tip and dovetailing with the spines of the next valve. Each spine is smooth on the external surface and along the inner margins. The sides of the valves are stippled with straight rows of areolae oriented parallel to each other and perpendicular to the valve end faces. Unlike in Aulacoseira enlarged single or paired areolae groups do not form the linking or separation spines, rather the spines arise entirety separate from the areolae. Each of the areolae has a thin, porous silica layer, a vela, on the internal side of the opening. In contrast, as is seen in Aulacoseira, the valves of E. wilsonii develop a distinct ringleiste on the internal surface of the valves. Between the ringleist and valve junction are a number of sessile pore openings through the valve surface, called rimoportulae. The two halves of the valves are linked via girdle bands with connecting ligulate strands which developed parallel poroid rows oriented perpendicular to the valve ends.
Paleoecology
The polysaccharide slime grown by E. wilsonii is suggested to have enhanced the preservation quality of organisms which were coated by the slime films before entombment in the lake sediments. The horsefly lake system has been interpreted as monomictic to possibly meromictic. If the lake was monomictic, the lake waters would have one period of surface layer and deep water mixing a year, but if it was meromictic, the water layers did not have any annual periods of mixing.
E. wilsonii is one of two diatoms known from Horsefly, with an undescribed species of Aulacoseira also being present. Unlike Aulacoseira giraffensis from the similarly aged Giraffe maar kimberlite pipe deposit in the North West Territories however, the undescribed Horsefly Aulacoseira species was a minor component of the lake flora, with E. wilsonii being the dominatant bloom florming species. Additionally the extant synurid "algae" species Mallomonas intermedia has also been recovered from Horsefly, while study of diatomitic sediments by George Mustoe (2005) from the McAbee Fossil Beds show undescribed Aulacoseiraceae diatoms and chrysophyte stomatocysts. Mustoe also examined sediment from the Allenby Formation near Princeton and found diatomitic layers, but noted that alteration and remineralization of the opal-A to opal-CT destroyed the original organic structures in the diatomite.
Paleoenvironment
The greater Eocene Okanagan Highlands likely had a mesic upper microthermal to lower mesothermal climate, in which winter temperatures rarely dropped low enough for snow, and which were seasonably equitable. The Okanagan Highlands paleoforest surrounding the lakes have been described as precursors to the modern temperate broadleaf and mixed forests of Eastern North America and Eastern Asia. Based on the fossil biotas the lakes were higher and cooler then the coeval coastal forests preserved in the Puget Group and Chuckanut Formation of Western Washington, which are described as lowland tropical forest ecosystems. Estimates of the paleoelevation range between higher than the coastal forests. This is consistent with the paleoelevation estimates for the lake systems, which range between , which is similar to the modern elevation , but higher. Estimates of the mean annual temperature have been derived from leaf margin analysis (LMA) of the Horsefly shales with the LMA returning a mean annual temperature of approximately . The estimated cold month mean temperature during the winter is placed at approximately . These estimates are lower than the mean annual temperature estimates given for the coastal Puget Group, which is estimated to have been between . The bioclimatic analysis for Horsefly suggests a mean annual precipitation amount of .
The Okanagan Highlands fossil sites, which includes the Eocene formations between the Driftwood Shales near Smithers, British Columbia in the north and the Klondike Mountain Formation surrounding Republic, Washington to the south have been described collectively as one of the "Great Canadian Lagerstätten" based on the diversity, quality and unique nature of the biotas that are preserved. The highlands temperate biome preserved across such a large transect of lakes recorded many of the earliest appearances of modern genera, while also documenting the last stands of ancient lines. The warm temperate highland floras in association with downfaulted lacustrine basins and active volcanism are noted to have no exact modern equivalents. This is due to the more seasonally equitable conditions of the Early Eocene, resulting in much lower seasonal temperature shifts. However, the highlands have been compared to the upland ecological islands in the Virunga Mountains within the Albertine Rift of the African rift valley.
References
†Eoseira
Ypresian plants of North America
Extinct flora of North America
†
†
Fossil taxa described in 2005
Horsefly Shales
† | Eoseira | [
"Biology"
] | 1,673 | [
"Diatoms",
"Algae"
] |
70,511,959 | https://en.wikipedia.org/wiki/Rosemary%20A.%20Dobbins | Rosemary Ann Dobbins ( Robbins; September 14, 1927 – October 24, 2006) was an American artist and photographer. She is most well known for her work as a technical illustrator and concept artist for NASA, where she created some of the most recognizable artist-rendered images of the American "Space Age". Beyond her NASA career, she was a multi-talented studio artist, photographer, and calligrapher.
Early life and education
Rosemary Ann Robbins was born on September 14, 1927, in a small but comfortable house on Maple Street in Hornell, New York. Her parents, Marta and Albert W. Robbins, already had three boys when Rosemary arrived. They viewed her as a "gift". Hers was a loving family, but one that suffered a great deal of hardship.
When she was eight, Rosemary contracted polio, most likely from exposure to the rising waters of the great flood of 1935 during which she and her family spent days assisting others through their hardships. Rosemary was completely paralyzed but still able to breathe; she struggled for several years but was able to overcome it through the use of revolutionary new therapies developed by Elizabeth Kenny. While she regained the ability to walk, her left side remained weak for the rest of her life.
In her early teens her oldest brother and protector, Albert Jr., suffered a head injury from playing college football. This was during the leather helmet era. The trauma to his brain was so severe he had to be committed to a sanitarium where, after many years of care, he eventually died.
At the beginning of WWII, Rosemary's two remaining brothers, Fred and Gary, both volunteered for military service. While still in high school, Rosemary herself worked as a volunteer in the local hospital where her duties included caring for returning soldiers, as well as victims of the 1944 polio outbreak.
In 1946, Robbins graduated from high school and completed secretarial school that same year. Immediately upon graduation, however, Rosemary was stricken with scarlet fever. She overcame this too, managing to recover just in time to start her first semester at art school.
From 1947 to 1950, Robbins studied at the Albright School of Art, part of the Buffalo Fine Arts Academy, the buildings of which today house the Albright-Knox Art Gallery. As a member of the artistic community in Buffalo, Dobbins had many connections to the art scene in New York City, where she traveled frequently and interacted with several well known artists of the period, many of whom would later collectively be known as the New York School. She was heavily influenced by both the Modernists and Abstract Impressionists of the era, yet also possessed a deep love for the painters of the Dutch Golden Age.
Career
Pre-NASA career
Robbins began her career while still in high school working as an artist for the Glidden Pottery in Alfred, New York. At her father's suggestion, she went to secretarial school even as she applied to art school. She was ultimately accepted into the Albright School of Art at the Buffalo Fine Arts Academy. To support herself she worked summers at the local Birds Eye Frozen Foods factory while living in a tent which she shared with two refugee students from the Netherlands. After completing her studies in 1950, Rosemary traveled to Holland by tramp steamer where she took up residence in Rotterdam with fellow artists she met through connections she had made in art school. She arrived just in time to take part in Rotterdam Ahoy! together with the local community of young artists. Based in Holland, she also traveled widely across post-war Europe. Her private archives contain many historically valuable sketchbooks from this period. In 1952, she returned to the U.S. and moved to West Lafayette, Indiana where an uncle had given her a lead on a position as a fashion illustrator and window decorator for a local department store.
Robbins was introduced to her future husband, Lt. Edward B. Dobbins Jr., in West Lafayette through mutual Dutch friends at a local production of Pygmalion. Lt. He was studying aerospace engineering at Purdue University while still actively serving in the military with the U.S. Army Missile Command. After a six-month courtship, they married in 1953; "Mrs. Robbins Dobbins" endured many jokes about her name. After Lt. Dobbins graduated with his Masters, the newlyweds were stationed in Huntsville, Alabama. Upon reentering civilian life in 1957, they moved to California. Lt. Dobbins had been recruited by Lockheed's "Skunk Works", and Rosemary landed jobs in technical illustration first at TRW Aerospace and then later also with Lockheed.
NASA career
During this time the U.S. Army Missile Command (MICOM) at Redstone Arsenal in Huntsville, Alabama increasingly focused on working toward human spaceflight. In 1950 Dr. Wehrner von Braun had arrived with 117 other German rocket scientists from Peenemünde to take up permanent residence there, and in 1956 he became technical director of a new division, the U.S. Army Ballistic Missile Agency(ABMA). In 1958 Lt. Dobbins was recruited back to MICOM in a civilian capacity to be a Unit Chief in the Propulsion Laboratory; his work in R & D at Redstone fell under the umbrella of ABMA and would eventually be used in the Apollo Program. Edward B. Dobbins Jr. was part of the team that engineered the retrorockets that separated the stages on the Saturn V. Upon their arrival back in Huntsville, Rosemary Dobbins was immediately hired by the newly formed NASA to be one of the key figures in the Art Department at the Marshall Space Flight Center working in both technical illustration as well as concept art. While waiting for her security clearance, Dobbins used the time to perfect her free hand lettering and calligraphy for technical illustration, eventually mastering nearly every form.
Dobbins remained at NASA for almost a decade, working during the most exciting and formative years of the American Space Program. She was also one of the first women in her division to be promoted to management. Artistically, the work was exceedingly challenging as it pre-dated the age of computers in graphic design. Most illustration work was done by airbrush, and all blocking and lettering work had to be done by hand. She worked on every major NASA project including the Juno II, Mercury, and Gemini Programs, but her main focus was on the Apollo Program, and beyond. Some of her later work even included concept art for a future planned moon station. Her illustrations were used in countless presentations, programs, and NASA publications. Many of her pieces have been on display in some of the most well-trafficked spaces of NASA, including a six-foot air-brushed illustration of the Saturn V after lift-off which hung in the main lobby of NASA headquarters for many years. Because her work was done for NASA as a government employee, it was uncredited for decades. Only recently, as NASA has begun to celebrate the work of the women in its early history who were pioneers in their fields, has Rosemary A. Dobbins finally been credited for her iconic artistic legacy.
NASA milestones
Dobbins broke several glass ceilings in her field, first in California and then at NASA. Her excellence and skill with an airbrush, her persistence and determination, along with perfectionism and discipline served her well. At NASA, she actually had two roles, that of illustrator and that of the wife of a rocket scientist. In 1960, NASA split from the U.S. Army Missile Command. When this happened Dr. Edward Dobbins Jr. chose to stay with the Army.
Throughout her career at NASA, Dobbins often faced uphill battles and fought to be accorded the same respect and recognition that was freely given to her male colleagues. In 1967 when she left NASA to raise her daughter, she used the occasion to bring to the attention of the department heads the many injustices she had endured over her decade there. In her final letter she left many recommendations on how to improve conditions for women.
Post-NASA career
After leaving NASA, Rosemary Dobbins established her own studio, which included a darkroom, and continued to hone her skills in art through study at the University of Alabama in Huntsville. She became a close friend, student and colleague of local artist Jack Dempsey who had been hired by UAH to create their new Art Department. Dempsey tried to recruit Dobbins to teach at UAH, but she declined. While she had accrued over 400 college credits of study beyond her art degree, and was Phi Kappa Phi, she never completed a Bachelor's. She did organize several local artist working groups, and taught in smaller circles out of her studio. On rare occasions she took on commercial commissions, and sold some of her work to select private collectors. During this time Dr. Edward Dobbins Jr. became the Director of the Rocket Propulsion Technology & Management Center at Redstone Arsenal under the R & D Division of MICOM, and Rosemary Dobbins continued with her social responsibilities as part of the "Dobbins Team".
1n 1966 their dream of adopting a child, which they had been pursuing for years, was finally realized when they brought their daughter home toward the end of that year. In 1968 they spent a year in Boston while Edward completed a second master's at MIT as a Sloane Fellow; in 1980 he completed his Ph.D. from UAH. Over the years, even as she raised her daughter, Rosemary continued to produce work out of her studio, constantly experimenting and at the same time attaining mastery over a wide range of mediums including photography, oil, watercolor, acrylic, airbrush, charcoal, ink, and mixed-media. Many of her pieces even included sculptural elements, or found object art. She often fluctuated between hyperrealism - especially in her watercolor work - influenced by Dempsey, and the Impressionism and Modernism of her art school days. In her later studio period, her painting more heavily reflected Abstract Modernism, while in her photography she focused on cultural themes. Her work was featured in local shows and state exhibitions throughout the 1960s, 70s and 80s, and won several awards.
Social justice involvement
As the daughter of a U.S. Commissioner, Dobbins witnessed first hand the impacts of both poverty and alcoholism.
As she grew older, she actively fought to right whatever wrongs she encountered. In high school she earned the nickname "Rocky" because she chose to wear her brother's warm flannel shirts and pants to school in winter in an era when girls were only allowed to wear dresses. She was threatened by her Principal with suspension if she did not go home and change, but she stood up for her rights and health. In the end she prevailed, and girls at Hornell High were allowed to dress warmly thereafter.
Later she found herself living in Northern Alabama at the height of the Civil Rights Movement. Rosemary Dobbins and her husband saw firsthand the injustice of the society in which they lived. As government employees they were not allowed to openly express their views, but both found ways to make known their support of Dr. Martin Luther King Jr. and of the movement he led. Rosemary and Edward had each grown up with families who actively pursued social justice. Dr. Dobbins' father, Ed Dobbins Sr., had fought against segregation in San Marcos, Texas decades before Brown vs the Board of Education finally forced the issue.
Later years and death
Apart from a few years when she moved with her husband to Texas to care for his aging parents, Dobbins spent her later life on Monte Sano Mountain in Huntsville, Alabama, a city she had come to love very deeply. Her work increasingly highlighted social issues or the wonder of nature. In the last few years her weakness from polio finally took its toll, compounded by other health conditions including a stroke; her hands began to tremble. Knowing she could not continue to produce work at the same high standard, in the late 1990s she gave up artwork altogether. She shifted her creative energy instead to music and mastered the clavichord.
After a loving 53 years of marriage, and a long successful career, Dobbins died on October 24, 2006, of heart failure. Her husband Edward passed away 6 years later in October 2012. Their daughter, Dr. Holly A. Dobbins, follows in their footsteps, furthering the cause of social justice and preserving and curating her mother's work. Rosemary and Edward Dobbins' memorial] is located in Maple Hill Cemetery, Huntsville, Alabama.
Illustrations
References
1927 births
2006 deaths
20th-century American illustrators
Photographers from New York (state)
20th-century American women photographers
20th-century American photographers
Space artists
People from Hornell, New York
NASA people
American women illustrators
Polio survivors | Rosemary A. Dobbins | [
"Astronomy"
] | 2,611 | [
"Space artists",
"Space art"
] |
70,513,413 | https://en.wikipedia.org/wiki/H3S10P | H3S10P is an epigenetic modification to the DNA packaging protein histone H3. It is a mark that indicates the phosphorylation the 10th serine residue of the histone H3 protein.
Depending on the environment in which it happens, the same phosphorylated residue might have drastically different consequences on chromatin structure. H3S10 and H3S28 phosphorylation is an excellent illustration of this duality: both phosphorylated residues are involved in chromatin compaction during mitosis and meiosis, as well as chromatin relaxation after transcription activation. Because of the diverse roles that these phosphorylation events play, individual residue phosphorylation can't be examined in isolation. The impact is determined by the cellular environment and interplay with other cis or trans changes.
The S10 phosphorylation is involved in mitosis, transcription, chromatin condensation, and UVB response. H3S10p causes chromosome condensation and segregation during cell mitosis. H3S10p temporarily increases during mitosis while H3K9me3 decreases and H3K9me3 recovers upon mitotic exit.
R loops are linked to H3S10P and chromatin condensation.
Nomenclature
The name of this modification indicates the protein phosphorylation of serine 10 on histone H3 protein subunit:
Serine/threonine/tyrosine phosphorylation
The addition of a negatively charged phosphate group can lead to major changes in protein structure, leading to the well-characterized role of phosphorylation in controlling protein function. It is not clear what structural implications histone phosphorylation has, but histone phosphorylation has clear functions as a post-translational modification.
Histone modifications
The genomic DNA of eukaryotic cells is wrapped around special protein molecules known as histones. The complexes formed by the looping of the DNA are known as chromatin.
Post-translational modification of histones such as histone phosphorylation has been shown to modify the chromatin structure by changing protein:DNA or protein:protein interactions. Histone post-translational modifications modify the chromatin structure. The most commonly associated histone phosphorylation occurs during cellular responses to DNA damage, when phosphorylated histone H2A separates large chromatin domains around the site of DNA breakage. Researchers investigated whether modifications of histones directly impact RNA polymerase II directed transcription. Researchers choose proteins that are known to modify histones to test their effects on transcription, and found that the stress-induced kinase, MSK1, inhibits RNA synthesis. Inhibition of transcription by MSK1 was most sensitive when the template was in chromatin, since DNA templates not in chromatin were resistant to the effects of MSK1. It was shown that MSK1 phosphorylated histone H2A on serine 1, and mutation of serine 1 to alanine blocked the inhibition of transcription by MSK1. Thus results suggested that the acetylation of histones can stimulate transcription by suppressing an inhibitory phosphorylation by a kinase as MSK1.
Mechanism and function of modification
Phosphorylation introduces a charged and hydrophilic group in the side chain of amino acids, possibly changing a protein's structure by altering interactions with nearby amino acids. Some proteins such as p53 contain multiple phosphorylation sites, facilitating complex, multi-level regulation. Because of the ease with which proteins can be phosphorylated and dephosphorylated, this type of modification is a flexible mechanism for cells to respond to external signals and environmental conditions.
Kinases phosphorylate proteins and phosphatases dephosphorylate proteins. Many enzymes and receptors are switched "on" or "off" by phosphorylation and dephosphorylation. Reversible phosphorylation results in a conformational change in the structure in many enzymes and receptors, causing them to become activated or deactivated. Phosphorylation usually occurs on serine, threonine, tyrosine and histidine residues in eukaryotic proteins. Histidine phosphorylation of eukaryotic proteins appears to be much more frequent than tyrosine phosphorylation. In prokaryotic proteins phosphorylation occurs on the serine, threonine, tyrosine, histidine or arginine or lysine residues. The addition of a phosphate (PO43-) molecule to a non-polar R group of an amino acid residue can turn a hydrophobic portion of a protein into a polar and extremely hydrophilic portion of a molecule. In this way protein dynamics can induce a conformational change in the structure of the protein via long-range allostery with other hydrophobic and hydrophilic residues in the protein.
Specific kinases for modification
The kinases Ipl1 (Sc) / AuroraB (Hs), RSK2, MSK1, ERK1, p38, Fyn, Chk1, PRK1 are involved in the S10 phosphorylation.
Epigenetic implications
The post-translational modification of histone tails by either histone-modifying complexes or chromatin remodeling complexes is interpreted by the cell and leads to complex, combinatorial transcriptional output. It is thought that a histone code dictates the expression of genes by a complex interaction between the histones in a particular region. The current understanding and interpretation of histones comes from two large scale projects: ENCODE and the Epigenomic roadmap. The purpose of the epigenomic study was to investigate epigenetic changes across the entire genome. This led to chromatin states, which define genomic regions by grouping different proteins and/or histone modifications together.
Chromatin states were investigated in Drosophila cells by looking at the binding location of proteins in the genome. Use of ChIP-sequencing revealed regions in the genome characterized by different banding. Different developmental stages were profiled in Drosophila as well, an emphasis was placed on histone modification relevance. A look in to the data obtained led to the definition of chromatin states based on histone modifications. Certain modifications were mapped and enrichment was seen to localize in certain genomic regions.
The human genome is annotated with chromatin states. These annotated states can be used as new ways to annotate a genome independently of the underlying genome sequence. This independence from the DNA sequence enforces the epigenetic nature of histone modifications. Chromatin states are also useful in identifying regulatory elements that have no defined sequence, such as enhancers. This additional level of annotation allows for a deeper understanding of cell specific gene regulation.
Effect of modification
A substantial number of phosphorylated histone residues are associated with gene expression. Interestingly, these are often related to regulation of proliferative genes. Phosphorylation of serines 10 and 28 of H3 and serine 32 of H2B has been associated with regulation of epidermal growth factor (EGF)-responsive gene transcription. H3S10ph and H2BS32ph have been linked to the expression of proto-oncogenes such as c-fos, c-jun and c-myc.50-52 Furthermore, targeting H3S28 phosphorylation to promoters of genes such as c-fos and α-globin was shown to control their activation.53 Notably, phosphorylation of H3S10 and H3S28 is not exclusive to EGF stimulation, but it also increases upon UVB radiation. Phosphorylation of H3 on T11 and T6 has also been implicated in transcription regulation in response to androgen stimulation,54,55 and to DNA-damage in mouse cells.56
Phosphorylation of H3S10, T11 and S28 has been clearly associated with H3 acetylation, strongly implicating these modifications in transcription activation. Independent studies show that these phosphorylation events are mechanistically linked to Gcn5-dependent H3 acetylation (Fig. 1).57-59 Indeed, in EGF-stimulated cells, phosphorylation of H3S10 is tightly coupled to H3 K9ac and K14ac, both marks of transcriptional activation.51,60,61 It has been shown that phosphorylation of H3S10 promotes acetylation of H3K14 by the Gcn5 acetyltransferase in vitro and allows Gcn5-regulated gene transcription in vivo.57 A similar link has been described in yeast where H3S10 phosphorylated by Snf1 acts in concert with Gcn5-dependent H3K14 acetylation to enhance transcription.62 This functional link between H3S10ph and Gcn5 is likely mediated by the direct interaction of the acetyltransferase with the phosphorylated H3S10 residue, which has been observed in vitro.57,60 However, analysis of the c-jun promoter activation showed that K14ac appears before S10ph and that inhibition of S10 phosphorylation has no effect on K14ac, suggesting that these two events can be uncoupled.61,63 Interestingly, phosphorylation of the H3 tail on T11 in addition to S10 was shown to enhance its interaction with Gcn5 at promoters of Gcn5-dependent genes such as the cell-cycle regulators cyclin B and cdk1, leading to increased H3K9 and K14 acetylation and stimulation of transcription.54,56,58 Likewise, phosphorylation of H3S28 was found to promote K9 acetylation.59 Altogether, these data suggest complex crosstalk between phosphorylation of H3S10, T11 and S28 in the control of Gcn5-dependent H3 acetylation, gene expression, and cell proliferation.
Clinical significance
Methods
The histone mark can be detected in a variety of ways:
1. Chromatin Immunoprecipitation Sequencing (ChIP-sequencing) measures the amount of DNA enrichment once bound to a targeted protein and immunoprecipitated. It results in good optimization and is used in vivo to reveal DNA-protein binding occurring in cells. ChIP-Seq can be used to identify and quantify various DNA fragments for different histone modifications along a genomic region.
2. Micrococcal Nuclease sequencing (MNase-seq) is used to investigate regions that are bound by well-positioned nucleosomes. Use of the micrococcal nuclease enzyme is employed to identify nucleosome positioning. Well-positioned nucleosomes are seen to have enrichment of sequences.
3. Assay for transposase accessible chromatin sequencing (ATAC-seq) is used to look in to regions that are nucleosome free (open chromatin). It uses hyperactive Tn5 transposon to highlight nucleosome localisation.
See also
H3S28P
References
Epigenetics
Post-translational modification | H3S10P | [
"Chemistry"
] | 2,415 | [
"Post-translational modification",
"Gene expression",
"Biochemical reactions"
] |
70,513,530 | https://en.wikipedia.org/wiki/The%20Traffic%20in%20Women%3A%20Notes%20on%20the%20Political%20Economy%20of%20Sex | The Traffic in Women: Notes on the "Political Economy" of Sex is an article regarding theories of the oppression of women originally published in 1975 by feminist anthropologist Gayle Rubin. In the article, Rubin argued against the Marxist conceptions of women's oppression—specifically the concept of "patriarchy"—in favor of her own concept of the "sex/gender" system. It was by arguing that women's oppression could not be explained by capitalism alone as well as being an early article to stress the distinction between biological sex and gender that Rubin's work helped to develop women's and gender studies as independent fields. The framework of the article was also important in that it opened up the possibility of researching the change in meaning of this categories over historical time. Rubin used a combination of kinship theories from Lévi-Strauss, psycho-analytic theory from Freud, and critiques of structuralism by Lacan to make her case that it was at moments where women were exchanged (principally through marriage acts) that bodies were engendered and became women. Rubin's article has been republished numerous times since its debut in 1975, and it has remained a key piece of feminist anthropological theory and a foundational work in gender studies.
Origins and publication
Rubin began work on the article when she was an undergraduate at the University of Michigan, based on her wide readings in social science and humanities theory under her advisor Marshall Sahlins. At the time, Rubin wished to be a Women's Studies major, but no such program existed. Rubin therefore declared one as an independent field and became the first Women's Studies graduate from the university in 1972. At the university, Rubin took part in reading groups organized by members of the New Left, and she was enmeshed in Marxist theory and critiques. She became a reader of publications like the New Left Review, which exposed her also to the critiques and analyses of Marxism by Lacan and Althusser that informed her writing. She was struck at the time by how Marxists failed to adequately explain the roots of female oppression in the global world, and how Marxism subsumed the problem of female oppression within the problems of capitalism more generally. Encouraged by Sahlins, it was also during this time that she first read Claude Lévi-Strauss' book The Elementary Structures of Kinship. As Rubin would say in a later interview with Judith Butler: "It [Lévi-Strauss] completely blew my mind." In addition, Rubin was then reading the newly emergent strands of post-structuralist theory from French intellectuals.
The paper arose from several drafts of a term paper for a course she was taking with Sahlins. Parts of this term paper were reworked by Rubin to become a section of her undergraduate thesis, and it was this section that Rayna Reiter later excised and published in 1975 in the feminist anthology Toward an Anthropology of Women. Though the article was also published in a lesser known feminist studies journal at around the same time, it was from the anthology by Reiter that it gained a wide audience.
Summary
Rubin's article is about fully understanding and accounting for the generalized oppression of women in the world—in both industrial capitalist and other kinds of societies. Rubin refers to this part of the social as the "sex/gender system." In making this analysis, she combines elements of various theoretical frameworks.
She first attacks Marxism, arguing that it is unable to "fully express or conceptualize sex oppression." Marx offers a very useful account of women's role only in the industrial capitalist context. Men work for wage labor jobs—their surplus value being converted into profits for the ruling class or bourgeoisie—while women work at home to sustain and reproduce this labor. The problem with this analysis lies not in explaining the usefulness of this kind of reproductive labor to capitalism, as this is very apparent to Rubin. Rather, as Rubin puts it: "But to explain women's usefulness to capitalism is one thing. To argue that this usefulness explains the genesis of the oppression of women is quite another." Classical Marxism therefore fails to explain why it is the women should be so oppressed merely because they perform this reproductive labor.
Just as it cannot account for the oppression of women within capitalist societies, Marxism also cannot explain why it exists outside of them. Rubin provides several examples, such as in the New Guinea highlands and in the Amazon river valley, where the oppression of women thrives and yet capitalist conditions are not present. She also points out that the pre-capitalist European world was also not free of women's oppression. Rather than being inherent to it, the oppression of women therefore exists independently of capitalism as a system.
Rubin then turns to the work of Friedrich Engels. She uses Engels' method in The Origin of the Family, Private Property, and the State, wherein he argues that women's oppression has been inherited from the social systems prior to capitalism (such as feudal and slave economies). Rubin argues that "We need to pursue the project that Engels abandoned" and recognize that women's oppression is tied to the means of production in all social forms, not just capitalism.
As a method of studying this oppression in all social forms, Rubin examines kinship structures as they were theorized in The Elementary Structures of Kinship by Claude Lévi-Strauss. In particular, Rubin focuses on 1) the "gift exchange" of women and 2) Strauss' idea of incest as the ultimate human taboo. For Strauss, the marriage of women (in pre-capitalist forms of society) was always a form of gift exchange. The incest taboo functioned to promote these exchanges of women between families. By forbidding certain kinds of marriage between kin, it ensured that other forms of marriage would take place. Strauss showed that men were principally in control of the exchange and reception of women, or a kind of kinship exchange, rather than simply a gift exchange based on principles of reciprocity (as Marcel Mauss argued in his essay, The Gift). Rubin considers this "exchange of women" to be an "initial step toward building an arsenal of concepts with which sexual systems can be described."
Rather than describing it merely in kinship terms as Strauss did, Rubin wants to also highlight the economic implications of this exchange. She holds that the Lévi-Straussian anthropological analysis based on terms of kinship cannot explain how gender arises and is connected to certain human bodies. This is because the incest taboo is not so universal as Strauss would have us think. There are certain groups of people where incest is normal and "such a marital future is taken for granted." Therefore, it cannot be the universal basis for why gender exists and why certain rights are reserved solely for men.
Rubin investigates the incest taboo further by bringing in the Oedipus Complex theory of Sigmund Freud. Rubin focuses on how Freudian theories of sexual repression (wherein young girls repress their sexual desires for their mothers) lead to a world where "language and...cultural meanings" are "imposed upon anatomy." Drawing upon Lacan's analysis of the symbolic exchange of the phallus, Rubin complicates Freud's Oedipal analysis. Rubin stresses the point that girls and women cannot give the phallus—they can only receive it "but only as a gift from a man." It is ultimately only by coming to terms with this lack of the ability to give the phallus that girls/women recognize themselves as such. In other words, they are to be exchanged and "trafficked," and this is the idea that defines their gender identity as it relates to their sexual, bodily or biological being.
In her conclusion, Rubin argues for a feminist analysis of the problem of the sex/gender system. She argues that it is only by seeing the system in total—in its symbolic, cultural, and economic implications—can we ask the appropriate questions of it: "there are other questions to ask of a marriage system than whether or not it exchanges women." Rubin calls for new research on the sex/gender system in different contexts, arguing that scholars should ask for what purpose this exchange transpires in different societies.
Reception and criticism
Rubin has continued to work on the ideas raised in the article throughout her scholarly career. Her 1982 article, "Thinking Sex: Notes for a Radical Theory of the Politics of Sexuality" was considered by Rubin herself to be a "corrective" to some of her arguments in "The Traffic in Women." Rubin also revisited the article directly in Deviations: a Gayle Rubin Reader in 2020, explaining the significance of the terms "traffic" and "trafficking" that were used in the article's original title. In addition, most of Rubin's other scholarly work continues to be concerned with the themes of sexuality and gender.
In a talk at a conference on sexuality in 2011, scholar Susan Stryker noted the continuing influence of the piece nearly 40 years since its publication. She also remarked upon how Rubin's work and successful career which "skirted the margins of academe before ultimately finding a place within it" was inspiring to her own career in academia, a career that was made difficult by the oppression faced since she came out as a transgender woman in 1991.
Notably, Judith Butler has cited the work as key for their own studies on gender and sex. In a 2012 interview between the two, Butler observed that many think of Rubin as an agenda setter for "the methodology for lesbian and gay studies" as well as feminist theory.
Outside of anthropology, the article has also been critically engaged by philosophers, labor scholars, and others broadly interested in feminist ideas. Most of the criticisms surrounding the article came some years after its publication, the result of scholars questioning the psychoanalysis that Rubin used. Cultural critic Laura Kipnis wrote a response to the article in 2006, wherein she questioned whether the psychoanalysis employed by Rubin did not lead to an overly deterministic assessment of women's lives. Joan Wallach Scott, meanwhile, in "Gender, a Useful Category of Historical Analysis," questioned whether Rubin's psychoanalysis could effectively help the historian to interpret historical actors. Scott stressed that historical actors do not "always or literally fulfill the terms of their society's prescriptions or of our analytic categories." The historian should therefore be cautious when using psycho-analysis and recognize that subjects may live their lives on terms other than those given by historians and their own cultures.
Bibliography and further reading
Cherniavsky, Eva. "On (the Impossibility of) Teaching Gayle Rubin. Feminist Formations 32, no. 1 (2020): 88-95.
Duggan, Lisa. “LOVE AND ANGER: Scenes from a Passionate Career.” GLQ 17, no. 1 (2011): 145–53.
Houston, David L. R. “GAYLE RUBIN (1949-).” Routledge Key Guides: Fifty Key Anthropologists, 2010.
Kipnis, Laura. "Response to "The Traffic in Women." Women's Studies Quarterly 34, no. 1/2 (2006): 434–437.
Parvulescu, Anca. The Traffic in Women's Work: East European Migration and the Making of Europe. Chicago, IL: University of Chicago Press, 2014. P. 21–49.
Pergadia, Samantha. "Geologies of Sex and Gender: Excavating the Materialism of Gayle Rubin and Judith Butler." Feminist Studies 44, no. 1 (2018): 171–196.
Povinelli, Elizabeth A. “Feminism as a Way of Life.” Women’s Studies Quarterly 34, no. 1/2 (2006): 438–41.
Rubin, Gayle. "The Traffic in Women: Notes on the "Political Economy" of Sex." In Ellen Lewin, Feminist Anthropology, a Reader. Malden, MA: Blackwell Publishing Ltd, 2006.
Rubin, Gayle and Judith Butler. "Sexual Traffic: Interview with Gayle Rubin by Judith Butler." In Gayle Rubin, Deviations: A Gayle Rubin Reader (2012): 276–309.
Scott, Joan W. "Gender: A Useful Category of Historical Analysis." The American Historical Review 91, no. 5 (Dec., 1986): 1053–1075.
Stryker, Susan. "The Time Has Come to Think About Gayle Rubin. GLQ 17, no. 1 (Jan., 2011): 79–83.
References
Wikipedia Student Program
Feminist literature
American essays
Feminism and psychoanalysis
Gender studies publications
Kinship and descent | The Traffic in Women: Notes on the Political Economy of Sex | [
"Biology"
] | 2,556 | [
"Behavior",
"Human behavior",
"Kinship and descent"
] |
70,513,943 | https://en.wikipedia.org/wiki/Carbon%20tech | Carbon tech is a group of existing and emerging technologies that are rapidly transforming oil and gas to low emissions energy. Combined, these technologies take a circular carbon economy approach for managing and reducing carbon footprints, while optimizing biological and industry processes. It is built on the principles of the circular economy for managing carbon emissions: to reduce the amount of carbon emissions entering the atmosphere, to reuse carbon emissions as a feedstock in different industries, to recycle carbon through the natural carbon cycle with bio energy, and to remove carbon and store it. Carbon tech provides a third option for climate and environmental policy as an alternate to the binary business as usual and radical change.
Carbon management can be achieved through nature-based solutions such as reforestation and afforestation, or through technological strategies. Technologies available range from Carbon Capture, Utilization and Storage (CCUS), to negative emissions technologies such as bio energy with carbon capture and storage, direct air carbon capture, as well as enhanced weathering, bio fuel, and biochar from waste that exists in today's processes.
Principles
The circular carbon economy is a closed loop system that encompasses 4Rs - Reduce, Reuse, Recycle, and Remove and applies them to managing carbon emissions.
Reduce
Energy efficiency, flaring minimization, modern SCADA controls, artificial intelligence, and making consumer products greener are among the strategies used to control the anthropogenic release of carbon emissions. It is complementary to opportunities to reduce fossil fuel use through substitution with low-carbon energy sources like nuclear, hydropower, bioenergy, and non-carbon emitting renewables.
Reuse
Carbon can be reused by pooling streams for energy generation, in waste management and product manufacturing. It can be reused in fuels, enhanced oil recovery, chemicals, bioenergy, food and beverages.
can be reused in building materials and provides a form of long-term storage.
Recycle
CO₂ can be chemically transformed through organic chemistry into different products such as fertilizers, cement, bio fuels, vodka, carbon nano tubes, material coatings, plastics, methanol, diamonds, clothing, foam, and detergents.
CO₂ is also transformed into other forms of energy like synthetic fuels. Synthetic hydrocarbon fuels are of importance in the aviation industry due to few low-carbon alternatives available.
Remove
Carbon emissions are captured both at the combustion stage and directly from the atmosphere, then stored into deep underground geological formations. Examples are capturing CO₂ from coal and natural gas power plants, hydrocarbon fuels, and heavy industries such as steel and cement manufacturing.
Planting flora, such as mangroves, also contributes toward reduction by increasing photosynthesis. Mangrove trees are among the largest stores of blue carbon.
Carbon tech globally
The IEA estimates that energy efficiency measures are projected to represent over 40% of the emissions abatement needed by 2040 to be in line with the Paris Agreement. IRENA concludes that renewable energy and energy efficiency measures can potentially deliver more than 90% of the carbon emission cuts needed under the Paris Agreement.
According to the U.N.’s Intergovernmental Panel on Climate Change, carbon tech solutions will capture almost as many emissions as renewables will reduce by the end of the century. The IEA also notes that when oil and gas are produced through enhanced oil recovery, the full lifecycle emissions intensity can be neutral or even carbon-negative.
According to a new report by research and consultancy firm Wood Mackenzie, Canada is a leader in carbon tech with projects underway that could reduce Canada's greenhouse gas emissions by up to 60% of their 2030 goal.
References
Carbon
Climate engineering
Carbon capture and storage | Carbon tech | [
"Engineering"
] | 741 | [
"Planetary engineering",
"Geoengineering",
"Carbon capture and storage"
] |
70,514,441 | https://en.wikipedia.org/wiki/Atribacter | Atribacter is a genus of bacteria of the candidate phylum Atribacterota with one known species (Atribacter laminatus).
Phylogeny
See also
List of bacteria genera
List of bacterial orders
References
Bacteria by classification
Bacteria genera
Monotypic bacteria genera
Taxa described in 2021 | Atribacter | [
"Biology"
] | 64 | [
"Bacteria stubs",
"Bacteria by classification",
"Bacteria"
] |
70,514,702 | https://en.wikipedia.org/wiki/Methidiumpropyl-EDTA | Methidiumpropyl-EDTA (MPE) is composed of the DNA intercalator methidium covalently attached to the metal chelator ethylenediaminetetraacetic acid (EDTA) by a short linker. MPE nonspecifically binds and cleaves DNA at multiple locations.
See also
Ethidium bromide
References
DNA intercalaters
Tricarboxylic acids | Methidiumpropyl-EDTA | [
"Chemistry"
] | 91 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
70,515,748 | https://en.wikipedia.org/wiki/Mercedes-Benz%20DTM%20V8%20engine | The Mercedes-Benz DTM V8 engine is a prototype, four-stroke, 4.0-liter, naturally aspirated V-8 racing engines, developed and produced by Mercedes-Benz for the Deutsche Tourenwagen Masters, between 2000 and 2018.
Engine
The Mercedes-Benz DTM V8 engine is a , naturally-aspirated, V8 engine, with a power output of between and a maximum torque . It is a 90-degree V8 engine with four-valves per cylinder, uses indirect fuel injection, and has 2 x 28 mm air restrictors due to regulations.
Applications
AMG-Mercedes CLK-DTM
Mercedes-Benz AMG C-Class DTM (W203)
Mercedes-Benz AMG C-Class DTM (W204)
Mercedes-AMG C-Coupé DTM
References
V8 engines
Mercedes-Benz engines
Gasoline engines by model
Engines by model
Piston engines
Internal combustion engine | Mercedes-Benz DTM V8 engine | [
"Technology",
"Engineering"
] | 188 | [
"Internal combustion engine",
"Engines",
"Engines by model",
"Piston engines",
"Combustion engineering"
] |
70,516,451 | https://en.wikipedia.org/wiki/Inversion%20recovery | Inversion recovery is a magnetic resonance imaging sequence that provides high contrast between tissue and lesion. It can be used to provide high T1 weighted image, high T2 weighted image, and to suppress the signals from fat, blood, or cerebrospinal fluid (CSF).
Fluid-attenuated inversion recovery
Fluid-attenuated inversion recovery (FLAIR) is an inversion-recovery pulse sequence used to nullify the signal from fluids. For example, it can be used in brain imaging to suppress cerebrospinal fluid so as to bring out periventricular hyperintense lesions, such as multiple sclerosis plaques. By carefully choosing the inversion time TI (the time between the inversion and excitation pulses), the signal from any particular tissue can be suppressed.
Turbo inversion recovery magnitude
Turbo inversion recovery magnitude (TIRM) measures only the magnitude of a turbo spin echo after a preceding inversion pulse, thus is phase insensitive.
TIRM is superior in the assessment of osteomyelitis and in suspected head and neck cancer. Osteomyelitis appears as high intensity areas. In head and neck cancers, TIRM has been found to both give high signal in tumor mass, as well as low degree of overestimation of tumor size by reactive inflammatory changes in the surrounding tissues.
Double inversion recovery
Double inversion recovery is a sequence that suppresses both cerebrospinal fluid (CSF) and white matter, and samples the remaining transverse magnetisation in fast spin echo, where the majority of the signals are from the grey matter. Thus, this sequence is useful in detecting small changes on the brain cortex such as focal cortical dysplasia and hippocampal sclerosis in those with epilepsy. These lesions are difficult to detect in other MRI sequences.
History
Erwin Hahn first used inversion recovery technique to determine the value of T1 (the time taken for longitudinal magnetisation to recover 63% of its maximum value) for water in 1949, 3 years after the nuclear magnetic resonance was discovered.
References
Magnetic resonance imaging
Nuclear magnetic resonance
Quantum mechanics | Inversion recovery | [
"Physics",
"Chemistry"
] | 429 | [
"Nuclear magnetic resonance",
"Magnetic resonance imaging",
"Theoretical physics",
"Quantum mechanics",
"Nuclear physics"
] |
70,518,743 | https://en.wikipedia.org/wiki/The%20American%20Architect | The American Architect was a weekly periodical on architecture published between 1876 and 1938. Originally titled The American Architect and Building News, in 1909 the magazine changed its name to The American Architect. In 1921, it changed name again to The American Architect and the Architectural Review, the second part of the name being the serial it absorbed.
The magazine reverted to its original name in 1925, and was published for another thirteen years. Its final edition, volume 152, was published in 1938, when it was absorbed into Architectural Record.
The magazine was originally published by Ticknor and Company Publishers, based on Tremont Street in Boston, Massachusetts. It was later published by Swetland Publishing Company and Standard Publishing.
References
External links
"American Architect and Architecture" - US Modernist
Visual arts magazines published in the United States
Annual magazines published in the United States
Defunct architecture magazines
Magazines established in 1876
Magazines disestablished in 1938
Defunct magazines published in New York City
Defunct magazines published in Boston | The American Architect | [
"Engineering"
] | 192 | [
"Architecture stubs",
"Architecture"
] |
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