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66,086,711 | https://en.wikipedia.org/wiki/The%20Trouble%20with%20Gravity | The Trouble with Gravity: Solving the Mystery Beneath Our Feet is a nonfiction popular science book by Richard Panek and published by Houghton Mifflin Harcourt on July 9, 2019.
Content
The book begins its first chapter by discussing ancient history and old beliefs regarding gravity and what lies above. This includes a discussion of belief in gods and how those religious views were shaped by the existence of gravity and its prevalence on living beings and all matter. The topics of Mount Olympus and stories among Aboriginal cultures in Australia are discussed in how the sky is believed to be separate from the earth and creates a separation between humans and the divine. The book points out that gravity was often seen in such context as something that only affects people on Earth and not as a universal force. Authors and those more on the philosophical end of the topic are also considered, including Dante Alighieri and Ernst Mach.
The second chapter investigates how gravity formed from the beginning of the universe and also how the Big Bang may have created a large number of parallel universes and that gravity is not sourced in our universe, but is leaking through spacetime into ours. Then, Panek moves on to human history and how the motion of gravity was first discovered, identifying the revolution that Isaac Newton's theories on gravity had on the general public. A series of other scientists and their chronological discoveries about gravity are delved into, including John Philoponus, Nicolaus Copernicus, Galileo Galilei, Albert Einstein, and Werner Heisenberg.
Style and tone
Publishers Weekly noted that the book's "inquisitive, fine-tuned narrative is full of character" and that it departs from other science books on similar topics by having a "friendly casualness of a coffee-shop chat". The heavy topics and complex science investigated in the book have the potential to bog down the reader, Undark Magazine writer Dan Falk pointed out, but Panek's writing style manages to deliver the topic with "humility and humor".
Critical reception
Kirkus Reviews calls The Trouble With Gravity a "useful primer on a force that still inspires mystery" and that, despite philosophical shortcomings that some may have, others will "enjoy Panek’s expert description" on the complex field of study. Clara Moskowitz for Scientific American writes that this "beautiful and philosophical investigation of nature’s weakest force" will help provide insights to readers, despite not being able to answer the fundamental question regarding gravity. Library Journal reviewer Sara R. Tompson calls it "one of the best of the postgravitational-waves-discovery physics books" and that all readers would find the text accessible. Shelf Awareness calls the book's glimpse into the mysteries of gravity "thought-provoking" and that while any definitive answers may not be forthcoming, The Trouble With Gravity still gives "much to contemplate".
References
Further reading
2019 non-fiction books
Physics books
Cosmology books
Astronomy books
Houghton Mifflin books
Popular science books
Gravity | The Trouble with Gravity | [
"Astronomy"
] | 609 | [
"Astronomy books",
"Works about astronomy"
] |
66,087,885 | https://en.wikipedia.org/wiki/Ketamine%20in%20society%20and%20culture | Ketamine has had a wide variety of medicinal and recreational uses since its discovery in 1962.
Generic names
Ketamine is the English generic name of the drug and its and , while ketamine hydrochloride is its , , , and . Its generic name in Spanish and Italian and its are ketamina, in French and its are , in German is , and in Latin is .
The S(+) stereoisomer of ketamine is known as esketamine, and this is its while esketamine hydrochloride is its .
Brand names
Ketamine is sold throughout the world primarily under the brand name Ketalar. It is also marketed under a variety of other brand names, including Calypsol, Ketamin, Ketamina, Ketamine, Ketaminol, Ketanest, Ketaset, Tekam, and Vetalar among others.
Esketamine is sold mainly under the brand names Ketanest, Ketanest-S, and Spravato.
Ketamine clinics
After the publication of the NIH-run antidepressant clinical trial, clinics began opening in which the intravenous ketamine is given for depression. This practice is an off label use of IV ketamine in the United States, though the intranasal version of esketamine has been approved by the FDA for treatment of depression In 2015 there were about 60 such clinics in the US; the procedure was not covered by insurance, and people paid between $400 and $1700 out of pocket for a treatment. It was estimated in 2018 that there were approximately 300 of these clinics. The number of clinics has been increasing rapidly.
A chain of such clinics in Australia, run by Aura Medical Corporation, was closed down by regulatory authorities in 2015. They found that the clinics' marketing was not supported by scientific research and the chain sent patients home with ketamine and needles to administer infusions to themselves.
Legal status
While ketamine is legally marketed in many countries worldwide, it is also a controlled substance in many countries.
Australia
In Australia, ketamine is listed as a schedule 8-controlled drug under the Poisons Standard (October 2015). Schedule 8 drugs are outlined in the Poisons Act 1964 as "Substances which should be available for use but require restriction of manufacture, supply, distribution, possession and use to reduce abuse, misuse and physical or psychological dependence."
Canada
In Canada, ketamine has been classified since 2005 as a Schedule I narcotic.
Hong Kong
In Hong Kong, since 2000, ketamine has been regulated under Schedule 1 of Hong Kong Chapter 134 Dangerous Drugs Ordinance. It can be used legally only by health professionals, for university research purposes, or with a physician's prescription.
Taiwan
By 2002, ketamine was classified as class III in Taiwan; given the recent rise of its prevalence in East Asia, however, rescheduling into class I or II is being considered.
India
In December 2013, the government of India, in response to rising recreational use and the use of ketamine as a date rape drug, has added it to Schedule X of the Drug and Cosmetics Act, requiring a special license for sale and maintenance for two years of records of all sales.
United Kingdom
In the United Kingdom, it became labeled a Class C drug on 1 January 2006. On 10 December 2013, the UK Advisory Council on the Misuse of Drugs (ACMD) recommended that the government reclassify ketamine to become a Class B drug. On 12 February 2014 the Home Office announced it would follow this advice "in light of the evidence of chronic harms associated with ketamine use, including chronic bladder and other urinary tract damage".
The UK Minister of State for Crime Prevention, Norman Baker, responding to the ACMD's advice, said the issue of ketamine's rescheduling for medical and veterinary use would be addressed "separately to allow for a period of consultation".
United States
Because of the increase in recreational use, ketamine was placed in Schedule III of the United States Controlled Substance Act in August 1999.
Recreational use
Recreational use of ketamine was documented in the early 1970s in underground literature (e.g., The Fabulous Furry Freak Brothers). It was used in psychiatric and other academic research through the 1970s, culminating in 1978 with the publishing of psychonaut John Lilly's The Scientist, and Marcia Moore and Howard Alltounian's Journeys into the Bright World, which documented the unusual phenomenology of ketamine intoxication. The incidence of non-medical ketamine use increased through the end of the century, especially in the context of raves and other parties. Its emergence as a club drug differs from other club drugs (e.g., MDMA), however, due to its anesthetic properties (e.g., slurred speech, immobilization) at higher doses; in addition, reports are common of ketamine being sold as "ecstasy". In the 1993 book E for Ecstasy (about the uses of the street drug Ecstasy in the UK), the writer, activist, and ecstasy advocate Nicholas Saunders highlighted test results showing that certain consignments of the drug also contained ketamine. Consignments of ecstasy known as "strawberry" contained what Saunders described as a "potentially dangerous combination of ketamine, ephedrine, and selegiline", as did a consignment of "Sitting Duck" ecstasy tablets.
The use of ketamine as part of a "post-clubbing experience" has also been documented. Ketamine's rise in the dance culture was most rapid in Hong Kong by the end of the 1990s.
Ketamine use as a recreational drug has been implicated in deaths globally, with more than 90 deaths in England and Wales in the years of 2005–2013. They include accidental poisonings, drownings, traffic accidents, and suicides. The majority of deaths were among young people. This has led to increased regulation (e.g., upgrading ketamine from a Class C to a Class B banned substance in the U.K.).
Unlike the other well-known dissociatives phencyclidine (PCP) and dextromethorphan (DXM), ketamine is very short-acting. It takes effect within about 10 minutes, while its hallucinogenic effects last 60 minutes when insufflated or injected, and up to two hours when ingested orally.
At subanesthetic doses—under-dosaged from a medical point of view—ketamine produces a dissociative state, characterised by a sense of detachment from one's physical body and the external world which is known as depersonalization and derealization. At sufficiently high doses, users may experience what is called the "K-hole", a state of dissociation with visual and auditory hallucinations. John C. Lilly, Marcia Moore, D. M. Turner and David Woodard (amongst others) have written extensively about their own entheogenic use of, and psychonautic experiences with, ketamine. Turner died prematurely due to drowning during presumed unsupervised ketamine use. In 2006 the Russian edition of Adam Parfrey's Apocalypse Culture II was banned and destroyed by authorities owing to its inclusion of an essay by Woodard about the entheogenic use of, and psychonautic experiences with, ketamine.
Because of its ability to cause confusion and amnesia, ketamine has been used for date rape.
Slang terms
Production for recreational use has been traced to 1967, when it was referred to as "mean green" and "rockmesc". Recreational names for ketamine include "Special K", "K", "Kitty", "Ket", "K2", "Vitamin K", "Super K", "Jet", "Super acid", "Mauve", "Special LA coke", "Purple", "Cat Valium", "Keller", "Kelly's Day", "New ecstasy", "Psychedelic heroin", "bump", "Majestic". A mixture of ketamine with cocaine is called "Calvin Klein" or "CK1". In Hong Kong, where illicit use of the drug is popular, ketamine is colloquially referred to as "kai-jai".
Usage
North America
According to the ongoing Monitoring the Future study conducted by University of Michigan, prevalence rates of recreational ketamine use among American secondary school students (grades 8, 10, and 12) have varied between 0.8 and 2.5% since 1999, with recent rates at the lower end of this range. The 2006 National Survey on Drug Use and Health (NSDUH) reports a rate of 0.1% for persons ages 12 or older with the highest rate (0.2%) in those ages 18–25. Further, 203,000 people are estimated to have used ketamine in 2006, and an estimated 2.3 million people used ketamine at least once in their life. A total of 529 emergency department visits in 2009 were ketamine-related.
In 2003, the U.S. Drug Enforcement Administration conducted Operation TKO, a probe into the quality of ketamine being imported from Mexico. As a result of operation TKO, U.S. and Mexican authorities shut down the Mexico City company Laboratorios Ttokkyo, which was the biggest producer of ketamine in Mexico. According to the DEA, over 80% of ketamine seized in the United States is of Mexican origin. As of 2011, it was mostly shipped from places like India, as cheap in cost as $5/gram. The World Health Organization Expert Committee on Drug Dependence, in its thirty-third report (2003), recommended research into ketamine's recreational use due to growing concerns about its rising popularity in Europe, Asia, and North America.
Europe
Cases of ketamine use in club venues have been observed in the Czech Republic, France, Italy, Hungary, The Netherlands, and the United Kingdom. Additional reports of use and dependence have been reported in Poland and Portugal.
Australia
Australia's 2019 National Drug Strategy Household Survey report shows a prevalence of recent ketamine use of 0.3% in 2004, 0.2% in 2007 and 2010, 0.4% in 2016 and 0.9% in 2019 in persons aged 14 or older.
Asia
In China, the small village of Boshe in eastern Guangdong was confirmed as a main production centre in 2013 when it was raided.
Established by the Hong Kong Narcotics Division of the Security Bureau, the Central Registry of Drug Abuse (CRDA) maintains a database of all the illicit drug users who have come into contact with law enforcement, treatment, health care, and social organizations. The compiled data are confidential under The Dangerous Drugs Ordinance of Hong Kong, and statistics are made freely available online on a quarterly basis. Statistics from the CRDA show that the number of ketamine users (all ages) in Hong Kong has increased from 1605 (9.8% of total drug users) in 2000 to 5212 (37.6%) in 2009. Increasing trends of ketamine use among illicit drug users under the age of 21 were also reported, rising from 36.9% of young drug users in 2000 to 84.3% in 2009.
A survey conducted among school-attending Taiwanese adolescents reported prevalence rates of 0.15% in 2004, 0.18% in 2005, and 0.15% in 2006 in middle-school (grades 7 and 9) students; in Taiwanese high-school (grades 10 and 12) students, prevalence was 1.13% in 2004, 0.66% in 2005, and 0.44% in 2006. From the same survey, a large portion (42.8%) of those who reported ecstasy use also reported ketamine use. Ketamine was the second-most used illicit drug (behind ecstasy) in absconding Taiwanese adolescents as reported by a multi-city street outreach survey. In a study comparing the reporting rates between web questionnaires and paper-and-pencil questionnaires, ketamine use was reported a higher rate in the web version. Urine samples taken at a club in Taipei, Taiwan, showed high rates of ketamine use at 47.0%; this prevalence was compared with that of detainees suspected of recreational drug use in the general public, of which 2.0% of the samples tested positive for ketamine use.
Law enforcement
In the late 2010s and early 2020s, law enforcement agencies in some U.S. states began directing paramedics to use ketamine to sedate people under arrest, sometimes under the auspices of treatment for the controversial diagnosis "excited delirium". The American Society of Anesthesiologists and American College of Emergency Physicians oppose the use of ketamine or any similar agent to incapacitate someone solely for a law enforcement purpose.
References
Drugs
Drug culture | Ketamine in society and culture | [
"Chemistry"
] | 2,704 | [
"Pharmacology",
"Chemicals in medicine",
"Drugs",
"Products of chemical industry"
] |
66,088,053 | https://en.wikipedia.org/wiki/Gravitational%20Wave%20High-energy%20Electromagnetic%20Counterpart%20All-sky%20Monitor | Gravitational Wave High-energy Electromagnetic Counterpart All-sky Monitor (GECAM) () is a space observatory composed of a constellation of two X-ray and gamma-ray all-sky observing small satellites, called GECAM A (aka KX 08A or Xiaoji, COSPAR 2020-094A) and GECAM B (aka KX 08B or Xiaomu, COSPAR 2020-094B), for research in electromagnetic counterparts of gravitational waves (GWs). It was launched on 9 December 2020 from the Xichang Satellite Launch Center at 20:14 UTC by a Long March 11 rocket. GECAM will focus on detecting electromagnetic counterparts of gravitational waves. In addition to signals from GWs, the observatory studies Ultra-long GRBs, X-ray Flashes, X-ray-rich GRBs, Magnetars and Terrestrial Gamma-ray Flashes.
References
Space telescopes
Spacecraft launched by Long March rockets | Gravitational Wave High-energy Electromagnetic Counterpart All-sky Monitor | [
"Astronomy"
] | 187 | [
"Space telescopes",
"Astronomy stubs",
"Spacecraft stubs"
] |
66,088,171 | https://en.wikipedia.org/wiki/Adam%20Block%20%28astrophotographer%29 | Adam David Block (born 1973) is an American astrophotographer, astronomy researcher, writer and instructor.
Biography
Block grew up in Rhode Island and Georgia, moving west in 1991 to attend the University of Arizona. In 1996, he earned his B.S. degree in Astronomy and Physics. After graduation, he was employed by the National Optical Astronomy Observatory for its public outreach program on Kitt Peak, which he did for nine years. In 2007 he founded the Mount Lemmon SkyCenter for the University of Arizona, which offers public stargazing programs as well as specialized programs in astrophotography. From 2016 on, he has continued work at Steward Observatory, the research arm of the Department of Astronomy at the University of Arizona. Much of his current work concerns characterizing the night sky and space domain awareness.
Astrophotographer
From the age of 13, Block has been an avid astrophotographer. His images and techniques have been featured in Astronomy Magazine, Sky & Telescope, National Geographic, Scientific American and L'Astronomie. Many have been used by space-based observatories as references for ground-based broadband images of objects. NASA has used Block's images over 100 times as Astronomy Picture of the Day.
Block describes himself as a popularizer of astronomy through public outreach, but that "... astrophotography has much greater reach since the images I create can be seen by people around the world.” At the 2012 Advanced Imaging Conference, he received the annual Hubble Award for special contributions to the field of astroimaging.
The Minor Planet Center credits Block with the discovery of asteroid 45298 Williamon, made on January 5, 2000. He also has an asteroid named for him, 172525 Adamblock.
Block also discovered stellar tidal star streams associated with NGC 3614 in February 2015.
Block offers instruction in astrophotography and techniques of image processing, both through magazine articles and personally through his online studios.
Gallery
Images by Adam Block, Mount Lemmon SkyCenter.
References
External links
Adam Block Photos
Adam Block Studios - Instruction in Astrophotography
Astrophotographer: Adam Block (YouTube video)
Mount Lemmon SkyCenter
NOIRLab
1973 births
Living people
21st-century American astronomers
Astrophotographers
University of Arizona alumni | Adam Block (astrophotographer) | [
"Astronomy"
] | 466 | [
"People associated with astronomy",
"Astrophotographers"
] |
66,089,487 | https://en.wikipedia.org/wiki/CD38-IN-78c | CD38-IN-78c is a drug which acts as a potent and selective inhibitor of the glycoprotein enzyme CD38. In animal studies it boosts levels of nicotinamide adenine dinucleotide (NAD+) in tissues via inhibition of CD38 mediated breakdown of nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN), and has been shown to ameliorate metabolic dysfunction associated with the aging process. It also has potential therapeutic application in the treatment of asthma.
References
Enzyme inhibitors | CD38-IN-78c | [
"Chemistry"
] | 116 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
66,089,784 | https://en.wikipedia.org/wiki/Wasp%20dope | Wasp dope, or wasping, also known by the street name KD or Katie, refers to the ingestion of common household insecticides either combined with or as a substitute for more conventional addictive substances that cause euphoria, such as methamphetamine or crack cocaine. Wasp dope is an emerging trend in the southern United States, although there are obscure reports of insecticide abuse dating back to the 1980s.
History
The origin of wasp dope remains unclear, and very little research is available on wasp dope users.
In 1979, at a hearing before the United States House of Representatives, it was reported that there was knowledge about the abuse of Raid wasp killer among American drug users.
A July 2000 report from the Journal of Hand Surgery describes 5 patients in the United States who injected common bug poison. Extreme inflammation and liquefaction necrosis were among the pathologies observed in these cases.
Signs and symptoms
Although household bug sprays are relatively safe when used as intended, the act of huffing, smoking, snorting, drinking, plugging, vaping or injecting bug poison could result in irreversible neurological damage, or even death. Possible symptoms of ingesting bug poison include, but are not limited to: erratic behavior, nausea, headache, sore throat, extreme inflammation, redness of the hands and feet, auditory hallucinations, convulsions, coma, necrosis, and death.
Methods of ingestion
A case report from Texas describes two different ingestion methods. The patient would spray the insecticide onto a hot surface, which would cause it to crystallize. This purified material would then be inhaled or smoked. It is also said that the crystalline bug poison is dissolved in water, and injected intravenously.
A 1979 hearing before the United States Congress indicated that some American drug users were smoking Raid wasp killer.
Prevalence
Research published in 2020 suggested that 19% of substance abusers in Appalachian Kentucky have ingested wasp dope. The use of wasp dope is strongly associated with homelessness and methamphetamine use in this region.
References
Substance-related disorders
Insecticides
Psychoactive drugs | Wasp dope | [
"Chemistry"
] | 442 | [
"Psychoactive drugs",
"Neurochemistry"
] |
59,626,627 | https://en.wikipedia.org/wiki/European%20Project%20on%20Ocean%20Acidification | The European Project on Ocean Acidification (EPOCA) was Europe's first major research initiative and the first large-scale international research effort devoted to studying the impacts and consequences of ocean acidification. EPOCA was an EU FP7 Integrated Project active during four years, from 2008 to 2012.
The EPOCA consortium brought together more than 160 researchers from 32 institutes in 10 European countries (Belgium, France, Germany, Iceland, Italy, The Netherlands, Norway, Sweden, Switzerland, and the United Kingdom) and was coordinated by the French Centre National de la Recherche Scientifique (CNRS) with the project office based at the Institut de la Mer de Villefranche, France (formerly Observatoire Océanologique de Villefranche).
Scope
The research carried out through EPOCA was structured around four themes :
Theme 1 investigated the changes in ocean chemistry and biogeography across space and time. Paleo-reconstruction methods were used on several archives, including foraminifera and deep-sea corals, to determine the past variability in ocean chemistry and to tie these to present-day chemical and biological observations;
Theme 2 studied the sensitivity of marine organisms, communities and ecosystems to ocean acidification. Key climate-relevant biogeochemical processes such as calcification, primary production and nitrogen fixation were investigated using a large array of techniques, ranging from molecular tools to physiological and ecological approaches. Perturbation experiments were carried out both in the laboratory and in the field, including a major large-scale offshore mesocosm experiment in Svalbard in 2010
Theme 3 focused on the integration of the results from Themes 1 and 2 in biogeochemical, sediment, and coupled ocean-climate models to better understand and project the responses of the Earth system to ocean acidification. Special attention was paid to feedbacks of physiological changes on the carbon, nitrogen, sulfur and iron cycles and how these changes will affect and be affected by future climate change;
Finally, Theme 4 synthesized the results from Themes 1-3 and assessed uncertainties, risks and thresholds ("tipping points") related to ocean acidification at scales ranging from subcellular to ecosystem and local to global scales. A second focus of this theme was to communicate the findings to fellow scientists but also to policy makers, media, schools and the general public.
Legacy
EPOCA significantly contributed to advancing the state of knowledge on ocean acidification and its impact on marine organisms and ecosystems. The project produced more than 200 research articles, equivalent to 20% of the peer-reviewed scientific literature on ocean acidification published during the period 2009-2012.
EPOCA leaves behind products still widely used by the international scientific community working on ocean acidification, such as :
EPOCA scientists designed and developed the R software package seacarb, which calculates parameters of the seawater carbonate system and includes functions useful for ocean acidification research;
EPOCA led the production of the community-reviewed “Guide to best practices in ocean acidification research and data reporting”, published in 2010 as a collaborative effort of EPOCA and international colleagues to provide guidance on design of ocean acidification experiments and to facilitate comparisons of studies and;
EPOCA maintained and pioneered several resources made available to the international ocean acidification research community :
a news stream on ocean acidification launched in 2006 by Jean-Pierre Gattuso, which provides daily information on the latest scientific articles, media coverage, meetings, and job and training opportunities;
a bibliographic database including research articles, books and book chapters with allocated keywords, launched in 1995 by Jean-Pierre Gattuso and;
a compilation of data from peer-reviewed studies investigating a biological response to ocean acidification.
References
External links
Oceanography
Marine biology
Climatological research
International climate change organizations | European Project on Ocean Acidification | [
"Physics",
"Biology",
"Environmental_science"
] | 768 | [
"Oceanography",
"Hydrology",
"Applied and interdisciplinary physics",
"Marine biology"
] |
59,626,799 | https://en.wikipedia.org/wiki/Anti-incinerator%20movement%20in%20China | The anti-incinerator movement in China refers to the series of environmental protests that have occurred in opposition to China's numerous planned and operating industrial waste incinerators. The construction of these waste-to-energy facilities, which has prompted the ensuing protest movement, operates as part of China's ongoing efforts to restructure its waste disposal system in regard to its status as the largest producer of municipal solid waste worldwide since 2004. Described by some as being a new type of NIMBY protest, the roots of the anti-incinerator movement can be traced back to the early 1990s, following the introduction of China's first generation of incinerator plants. The movement, however, began in earnest with the benchmark 2006 Liulitun protest taking place in Beijing.
Since the success of the Liulitun plant protest, in which the proposed incinerator in Beijing's Haidian district was indefinitely postponed, numerous other instances of dissent surrounding China's incinerator plants have transpired, with particularly notable examples occurring in Guangzhou, Wujiang and Panguanying. While the individual protests have differed in terms of participants, tactics used and government response, each has been demonstrably oriented around environmental and health concerns emanating from the pollution and potential human cost associated with operating waste-to-energy incinerators.
Despite various successes occurring for protests of this type, China's national government has continued to acknowledge incineration as a viable solution for managing municipal waste, and as such, has continued to plan and develop numerous incinerator plants throughout the country.
History
The first instances of dissent aimed at China's waste incinerators occurred as early as 1994, when the nation's first incinerator plant was implemented on the mainland. Since that time as many as 54 cases of incinerator-related disputes have been reported. The protests however did not begin achieving their current prominence and scope until the Liulitun protest in Beijing, which began in 2006 and extended into early 2011, ending with the ultimate cancellation of the incinerator project at its original location.
From these events in Beijing's Haidian district stemmed a series of other like-minded protests, led by individuals who had become empowered by the success of the protest in China's capital. Amongst these were protests in Guangzhou, Wujiang and Panguanying, all of which began during or around the time of 2009. In Guangzhou inhabitants of the residential Panyu district began opposing plans to construct a municipal waste incinerator in their area after coming across a posting on a government website. Eventually, by the end of 2011, protesters were able to get the project cancelled at its proposed site, with the government electing to move the plant elsewhere.
Similarly, in Pingwang, a town located outside Wujiang city in China's Jiangsu province, residents began opposing the construction of a nearby incinerator plant that was already nearing completion. Their collective efforts, which culminated in a large-scale peaceful demonstration occurring in late 2009, resulted in the plant's construction being halted pending further review. In the same year, in Panguanying, a small rural village in China's Hebei province, villagers utilized assistance from environmental NGOs and urban activists from Beijing to repeatedly halt the project, leading to the proposed plant being shelved after negotiations broke down.
In recent years, as China has continued to develop new waste incinerators, protests have occurred in such places as Lubo town, Zhaoqing city and Sihui city, all in China's Guangdong province. In 2017 there was another notable protest in the south-eastern city of Shenzhen opposing the development of the city's Shenzhen East Waste-to-Energy Plant, which would become one of the largest waste incinerators nationwide upon completion.
Key issues and participants
In each anti-incinerator protest, despite the variety of individuals involved, the common goal of protesters has consistently been the prevention or postponement of a planned or operational incinerator facility in their area. Moreover, given their localized nature, each protest has been mainly directed at the local government, though those that were able to transcend local bounds, through media coverage and intervention from activist groups, have been shown to adopt a broader context.
In the 2006 Beijing Liulitun protest, participants were largely made up of scholars and science or engineering professionals from nearby universities and businesses who resided the Haidian district. Given the academic backgrounds of these individuals and their prior objection of a noxious landfill already present in the area, the ensuing anti-incinerator protest was particularly conscious of the potential health risks associated with waste incineration. As research suggested to the protesters, incinerator plants, especially those from earlier generations, produce a variety of noxious byproducts containing dioxins, such as fly ash. Production of such harmful chemicals and concerns over how nearby communities would be affected has become the defining issue of the anti-incinerator movement.
During the Panyu protest in Guangzhou, participants consisted of long-time residents as well as recent migrants to the newly developed district, a majority of whom were unaware or felt they were not properly informed of the plans to construct an incinerator. As with the Liulitun protest, protesters in Panyu showed concern for their health as well the potential environmental impact of the proposed plant if it were constructed. As such, their demands ranged from a more accessible environmental impact assessment (EIA) to having the project be canceled outright. Like in Beijing, protesters were uniquely assisted by the occupations of professionals residing in the area, many of whom, in this case, were journalists, members of the local media and retired government bureaucrats.
In the protest of an incinerator plant being built in the town of Pingwang, which is located near the city of Wujiang, a majority of protesters were local residents. Being inspired by the successful Liulitun protest in Beijing, protesters aimed to prevent the completion of their own nearby plant, citing amongst their concerns the proven detrimental effects of waste incinerators.
Unlike previous protests of its kind, the 2009 Panguanying protest, which took place China's Hebei Province, exhibited participation which extended significantly beyond the local sphere. While initially only consisting of residents of the rural Panguanying village, protesters eventually garnered the support of urban environmental activists and legal professionals from Beijing. Participants in the Panguanying protest shared the environmental and health-related motivations of other similar demonstrations, however, they also aimed to expose the malpractice and deceit inherent in the planning and flawed environmental impact assessment of their town's incinerator plant.
Throughout the reported protests, various environmentalist groups have gotten involved and supported protesters including the Beijing-based Nature University, Friends of Nature and the Guangzhou-based Eco Canton, the creation of which stemmed directly from the Panyu protest.
Protest strategy and tactics
Tactics employed during anti-incinerator protests have included appealing to local officials, communicating over online services, conducting public demonstrations and utilizing media attention. Another shared factor of many of these protests has been their recognition and, in some cases, direct consultation or imitating of their predecessors.
During the Liulitun protest in Beijing, protesters, in emphasis of their concerns regarding the harmful health effects of waste incineration, drew up signs and T-shirts with phrases referencing the potential human cost of incinerators and assembled on World Environment Day, June 5, 2007, to express their objection. Protesters also sought legal help from environmental lawyers and produced a lengthy report articulating their opposition to the project, actions which were later emulated by protesters in Panguanying.
In Guangzhou, during the Panyu district protest, residents began by exploring the ramifications of municipal waste incinerators by conducting online research and visiting a nearby incinerator plant for reference. Protesters also visited the nearby village of Likeng where villagers had been conducting protests against their own incinerator since 2000, and thus had first-hand experience living close to a waste-to-energy plant. Eventually concluding that the proposed plant would be detrimental to their community, protesters in Panyu began writing letters to government officials and later took to the streets to publicly express their concerns. On October 25, 2009, in one such case, protesters marched near a supermarket wearing surgical and gas masks and carrying signs depicting various anti-incinerator messages. These actions eventually resulted in the police being called in and some arrests being made. A month later, following the government's announcement of a public reception to discuss community issues, protesters mobilized via online blogs and social media sites and arrived at the event in such numbers that the venue was incapable of accommodating everyone present.
Protesters in Pingwang similarly utilized the internet and various online bulletin boards to criticize their town's incinerator plant and mobilize protests against it. When online methods proved ineffective thousands residents took to the streets during October 2009 and occupied the planned incinerator facility for 2 days, leading to police being brought out and the protest being peacefully dispersed.
In the village of Panguanying protesters began by making a series of appeals to local government officials. When their concerns were rebuffed protesters began visiting other nearby villages to ask for their support, and, using the Liulitun protest as reference, produced their own report articulating their discontent for the development of an incinerator. Eventually a group of protesters traveled to Beijing and sought the help of prominent environmental lawyers who in turn connected them with various environmental activist groups and assisted in having their case be heard in the Qiaoxi District People's Court.
In cases such as Panguanying the role of media proved significant in bringing wider attention to the innately localized issue of the town's incinerator plant. Moreover, through connecting with the environmental NGO, Nature University, in Beijing, villagers were able to receive necessary educational and planning support.
In more recent years protesters have utilized modern communications and social media services such as Twitter and WeChat to organize their efforts and share information.
Government response
Given the marked success of protests in places such as Beijing and Guangzhou, it can be observed that the government has been notably responsive to the anti-incinerator movement. While in many cases police were dispatched to break up any public demonstrations, local governments have ultimately acknowledged protesters’ concerns and, in some cases, made such accommodations as canceling proposed incinerator projects or agreeing to relocate construction to less-populated areas. This can especially be seen in the case of Pingwang town, where the mass-mobilization of protesters forced the government to re-evaluate their initial dismissal of the residents' concerns. In cases such as the Panguanying protest, the local government responded first by assuring residents that pollution levels would not increase as a result of the proposed plant, though when protesters remained unswayed officials eventually relented and postponed the project.
Future developments
Despite various concessions having been made with regard to anti-incinerator protests, the Chinese government has maintained its commitment to waste-to-energy incinerators as a means to lessen the nation's ongoing waste burden. Following the cancellation of the Panyu plant in Guangzhou, the government, in a press conference during April 2012, affirmed its plans to build 4 new incinerators throughout the city to deal with growing amounts of municipal waste. Similarly, in Beijing, despite the success of the Liulitun protest, various incinerator plants have since been constructed, including the original Liulitun plant which was, in 2010, relocated to the nearby village of Dagong. Additionally, the national government has continued to implement various policies and initiatives to support incineration. Presently the number of waste incinerators operating in China has reached nearly 300 with 249 being in cities and 50 near small towns. Accordingly, there are plans to increase this number to meet the state sponsored goal of having nearly one third of the nation's garbage disposed of via incineration by 2030.
References
Environmentalism in China
Environmental issues in China
Incineration
Waste management in China
Environmental protests in China
Political movements in China | Anti-incinerator movement in China | [
"Chemistry",
"Engineering"
] | 2,447 | [
"Combustion engineering",
"Incineration"
] |
59,627,302 | https://en.wikipedia.org/wiki/Symmorphosis | Symmorphosis is the regulation of biological units to produce an optimal outcome. Symmorphosis is when a quantitative match of design and function within an organism defined within a functional system. Symmorphosis can be broken down into the three predictions that are required for organs to evolve within a species.
This proposes that if organs were matched structurally and functionally, and paired with the correct energy and minerals, the body would create an organ of optimal design. Some examples of this in the human body could be how the respiratory system distributes oxygen, how bones are structured to withstand stress, how blood vessels are designed to distribute blood throughout the body without using a lot of energy, or even how as a person becomes more physically fit or endures more cardio after their body has adjusted to maintain higher functioning demands. The use of symmorphosis can allow for fields of science to work with the field of evolutionary biology to better understand adaptation.
Requirements
For symmorphosis to occur, there must be three predictions or guidelines in place and functioning at the same time. These three predictions work together to let an organ function or organ system work at full potential.
Structure
When looking at the theory of symmorphosis, one must consider if the design in the organism is fully optimized. The structural design in terms of symmorphosis means that the organ is designed to allow full capacity of its function and can allow for adjustments to occur when necessary. This design must contain the sufficient amount of economy material for the organ needed. In this circumstance, economy material is the careful management of resources such as tissues.
Capacity
The functional capacity is when all functional units work together to determine the maximal capacity. Functional capacity is overall determined by the structural design. Once the design is optimized in terms of biological materials, then the structure must be taken into account. The structure of an organ determines the maximal functional capacity and the adjustments required for morphogenesis—the process that causes an organism to create its shape—to occur.
Performance
The third prediction states that if prediction two works in intermediate steps to create a function of an individual organ, then each step also helps create the upper limit of the function." This means that if multiple units work together in multiple steps, they function together to create an upper limit (e.g., Vo2max) in terms of function or ability.
Within the respiratory system
A common form of testing symmorphosis between species of mammals is to use comparative biology. The first system to use the proposed theory for symmorphosis is the oxygen pathway for mammals.
The original experimental method for symmorphosis was used to show if the design of the organs were relative to the static demands of the mammalian respiratory system. The respiratory system is a good example to study because it has one main function, the function has a measurable limit, the limit is variable, it has a sequence of structure, and each step of the sequence has functional parameters that are not fixed. A common pathway within the respiratory system is the oxygen pathway. This pathway is used because it is a good representation for mammals within most species—because it involves several organs that link together, and the overall function has a measurable upper limit. In particular, this testing helps identify structural elements that differ so they can carry the maximum amount of oxygen throughout the body.
Vo2max
The upper limit for the oxygen pathway is called the Vo2max. Vo2max is the maximal oxygen capacity that systems can take in, transport, and use oxygen. Vo2max can vary among individuals due to allometric variation (the differences in body mass), adaptive variation (differences in lifestyles), and the induced variation (amount of cardio exercise). Variation of any of the three types of variation should lead researchers to expect different parameters.
The oxygen cascade is one system with clear limits, and can help determine the Vo2max by components such as oxygen supply to the skeletal muscle mitochondria and the demand of oxygen by these skeletal muscle mitochondria. If oxygen is not transferred via skeletal muscle mitochondria, it can then be transferred across muscle capillaries.
Evolutionary implications
Symmophsis can be use as an analytical advancement that helps other fields of science—such as biochemistry, physiology, and astronomy—work with fields such as cell, molecular, and evolutionary biology. Combining these fields helps researchers better understand past biological adaptions.
In evolution, natural selection can hinder the design when looking at the guidelines for symmorphosis. Natural selection can alter the phenotype to increase fitness of a species. In doing this, natural selection can cause adaptations that can change the optimal structural. When the optimal structural design changes, it changes the amount of economy material that must be used, which changes the predictions.
Critiques
An issue with symmorphosis is the problem of having an optimal design for an organ if the organ contains multiple functions. An organ that performs multiple functions must compromise optimal performance of one function to perform another optimally. These complex components adding together dramatically decreases the chance that everything will optimally match. An example of this in mammals is the lungs. Researchers now claim that the lungs are an exception when considering the Lungs typically are only partially adjusted to maximal oxygen capacity in terms of adaptive and allometric variation and cause a fluctuation in these values.
In terms of symmorphosis, the capacity of each step of the oxygen cascade should match the demand of Vmax. In most cases this theory holds true with the exception of when an individual exceeds the Vmax. When Vmax is exceeded there then becomes developmental constraints as well as design constraints in terms of symmorphosis. When this occurs there is an unmatched capacity, although they may be similar they do not align with the predictions for symmorphosis.
References
Evolutionary biology
Physiology | Symmorphosis | [
"Biology"
] | 1,200 | [
"Evolutionary biology",
"Physiology"
] |
59,627,308 | https://en.wikipedia.org/wiki/Sexual%20selection%20in%20Arabidopsis%20thaliana | Sexual selection in Arabidopsis thaliana is a mode of natural selection by which the flowering plant Arabidopsis thaliana selects mates to maximize reproductive success.
Arabidopsis thaliana is a small flowering land plant in the family Brassicaceae, which is utilized as a model organism for genetic studies. While the plant's genomics are well understood, little is known about sexual selection processes and sex-biased genes in this species. It has been found that these genes associate with the sexually dimorphic traits of males and females, considering that both sexes of a species will have very similar genomes. These genes are preferentially expressed in the different sexes within a species, and tend to provide an accelerated rate of evolution resulting from a specific sex expressing the optimum phenotype to maximize fitness. A. thaliana is a self-fertilizing plant without sex chromosomes that is capable of utilizing sex-biased genes to potentially aid in adaptive evolution. There is little knowledge on how sex-biased genes function in A. thaliana's genome.
Arabidopsis thaliana
A. thaliana was discovered in the Harz Mountains in the 1500s with a native range that stretches on rough terrain across Eurasia, but has also established in North America as well. A. thaliana was identified as a model organism for genomic studies due to its small genome, consisting of only 5 chromosomes. A. thaliana has a relatively short life cycle, only taking approximately 5 weeks to reach full maturity after germination. This short life cycle makes it an ideal candidate as a model organism for genomic studies.
Sex-biased genes
Sex-biased genes are genes with expression exclusive to one sex and provide a potential means of rapid evolution in a species.
Variation between sexes
Male and female sex-biased genes of A. thaliana have major differences in expression and function. Male genes expressed in the pollen tube regions of the plant struggle in the initiation of protein evolution. This is the result of newly developed mutations being acted upon by positive selection. Female gametophytes differ significantly in their utilized number of sexually expressed genes compared to males. When looking at both types of gametophytes, both males and females shared approximately 20 genes that are expressed in similar fashion. It has also been found that 925 genes in A. thaliana are associated with the male gametophyte, consisting of those linked to sperm cells, pollen, and pollen tubes. On the other hand, approximately 196 genes have been identified to associate with the female gametophyte.
Function
The genes identified in the tissues of A. thaliana were able to be separated out and categorized based on location and function for both male and female reproductive organs. The male reproductive organs of the plant are much easier to be utilized for experimental procedures due to their capability to be easily isolated from the plant compared to the female organs. The genes that have been linked to pollen and pollen production show strong co-expression due to their classification as duplicated genes across various tissues. It has been identified that genes associated with pollen and the pollen tubes have a relatively high number of expressed polymorphisms through purifying selection. Identifiable features of adaptive evolution expressed in pollen associated genes are comparable to the increased levels of adaptive evolution in other comparable species. With adaptation regulated by mutation rates, the sex-biased genes associated with the male organs of the plant could show higher adaptation rates due to their presence being in a haploid state. In this haploid state, mutations are directly exposed to the opportunity of rapid selection. Pollen interactions associated with sporophytic tissue are not expressed in genes linked to female reproductive organs. The mechanisms involved in pollen formation and development of the pollen tube are important for pollen selection as well as protein composition of the pollen. Pollen surface proteins are produced in the sporophytic tissue of the anther and have expressed higher levels of purified selection with an increase in adaptive evolution from the oleopollenins of the anther.
Pollination mechanisms
A. thaliana is a self-pollinating plant compared to other closely related species, meaning it does not require pollen from other plants for fertilization. Self-pollination provides an effective means for plants to colonize new habitats effectively because they do not rely on pollen from another member of their species. By carrying both male and female reproductive organs, the effort for sexual reproduction is greatly diminished but comes at a cost.
Reduction of self-pollination
The implementation of self-pollination significantly reduces genetic variation in a population, and an established population of identical progeny presents limited opportunity for evolution on a genomic level throughout a species. The plant combats this through the utilization of both male and female sex organs which provides an environment with low rates of outcrossing through sex-biased genes. The result of low genetic variations in both A. thaliana gametophytes self-fertilization comes from the low rates of outcrossing. The low rates of outcrossing can be overcome by variations of heterogeneity in selection. This can happen based on the rare occurrence of outcrossing, which in A. thaliana, only occurs in the wild about 1% of the time. It has been found that rare occurrences of outcrossing can be as high as 15% in a given population. Researchers believe that even the 1% of occurrence is high enough of a rate to initiate genetic consistencies that can associate with sexual selection in A. thaliana.
Pollen competition
The presence of pollen competition when outcrossing occurs in a plant that utilizes self-fertilization allows recognition and selection of different pollen grains to fertilize the ovule. A. thaliana is closely related to Arabidopsis lyrata being that one diverged from the other through speciation. Although speciation has separated these species, they are still capable of providing a means of outcrossing between each other, initiating pollen competition within the plant. Although competition does occur among male gametophytes of both species, A. lyrata has very low instances of adaptive evolution compared to A. thaliana. This evidence is usually not the case in the instance of pollen competition across similar species, which generally results in increased rates of outcrossing. When outcrossing occurs generally there are much higher rates of genetic variation in progeny. There is little data on A. lyrata which results in little knowledge of whole genome polymorphisms.
Pollen associated gene interaction
It was determined that interactions associated between sporophytic tissue and pollen is exclusively expressed in the male gene sets. Therefore, the evidence suggests the importance of these interactions for understanding pollen selection by the plant. Other potential factors that play a role in pollen selection could be secreted pollen proteins, as well as protein composition. With major identified differences of pollen associated genes compared to other reproductive tissues, they can potentially be the underlying mechanisms correlated with sexual selection occurring during the prezygotic stage of pollination. This underlies the correlation between how selective pressure through the interactions between pollen grains as well as pollen tube formation provide an example of established sexual selection. A. thaliana provides an effective means to understand how even organisms that may appear limited in genetic variation based on reproductive strategies can still maintain a means of evolution through sex-biased genes and sexual selection through outcrossing.
References
Arabidopsis thaliana
Sexual selection | Sexual selection in Arabidopsis thaliana | [
"Biology"
] | 1,513 | [
"Evolutionary processes",
"Behavior",
"Sexual selection",
"Mating"
] |
59,627,310 | https://en.wikipedia.org/wiki/Hybrid%20incompatibility | Hybrid incompatibility is a phenomenon in plants and animals, wherein offspring produced by the mating of two different species or populations have reduced viability and/or are less able to reproduce. Examples of hybrids include mules and ligers from the animal world, and subspecies of the Asian rice crop Oryza sativa from the plant world. Multiple models have been developed to explain this phenomenon. Recent research suggests that the source of this incompatibility is largely genetic, as combinations of genes and alleles prove lethal to the hybrid organism. Incompatibility is not solely influenced by genetics, however, and can be affected by environmental factors such as temperature. The genetic underpinnings of hybrid incompatibility may provide insight into factors responsible for evolutionary divergence between species.
Background
Hybrid incompatibility occurs when the offspring of two closely related species are not viable or suffer from infertility. Charles Darwin posited that hybrid incompatibility is not a product of natural selection, stating that the phenomenon is an outcome of the hybridizing species diverging, rather than something that is directly acted upon by selective pressures. The underlying causes of the incompatibility can be varied: earlier research focused on things like changes in ploidy in plants. More recent research has taken advantage of improved molecular techniques and has focused on the effects of genes and alleles in the hybrid and its parents.
Dobzhansky-Muller model
The first major breakthrough in the genetic basis of hybrid incompatibility is the Dobzhansky-Muller model, a combination of findings by Theodosius Dobzhansky and Joseph Muller between 1937 and 1942. The model provides an explanation as to why a negative fitness effect like hybrid incompatibility is not selected against. By hypothesizing that the incompatibility arose from alterations at two or more loci, rather than one, the incompatible alleles are in one hybrid individual for the first time rather than throughout the population - thus, hybrids that are infertile can develop while the parent populations remain viable. The negative fitness effects of infertility are not present in the original population. In this way, hybrid infertility contributes in some part to speciation by ensuring that gene flow between diverging species remains limited. Further analysis of the issue has supported this model, although it does not include conspecific genic interactions, a potential factor that more recent research has begun to look in to.
Gene identification
Decades after the research of Dobzhansky and Muller, the specifics of hybrid incompatibility were explored by Jerry Coyne and H. Allen Orr. Using introgression techniques to analyze the fertility in Drosophila hybrid and non-hybrid offspring, specific genes that contribute to sterility were identified; a study by Chung-I Wu which expanded on Coyne and Orr's work found that the hybrids of two Drosophila species were made sterile by the interaction of around 100 genes. These studies widened the scope of the Dobzhansky-Muller model, who thought it likely that more than two genes would be responsible. The ubiquity of Drosophila as a model organism has allowed many of the sterility genes to be sequenced in the years since Wu's study.
Modern directions
With modern molecular techniques, researchers have been able to more accurately identify the underlying genetic causes of hybrid incompatibility. This has led to both the development of expansions to the Dobzhansky-Muller model. Recent research has also explored the possibility of external influences on sterility as well.
The "snowball effect"
An extension of the Dobzhansky-Muller model is the "snowball effect"; an accumulation of incompatible loci due to increased species divergence. Since the model posits that sterility is due to negative allelic interaction between the hybridizing species, as species become more diverged it follows that more negative interactions should develop. The snowball effect states that the number of these incompatibilities will increase exponentially over the time of divergence, particularly when more than two loci contribute to the incompatibility. This concept has been exhibited in tests with the flowering plant genus Solanum, with the findings supporting the genetic underpinnings of Dobzhansky-Muller: "Overall, our results indicate that the accumulation of sterility loci follows a different trajectory from the accumulation of loci for other quantitative species differences, consistent with the unique genetic basis expected to underpin species reproductive isolating barriers. ...In doing so, we uncover direct empirical support for the Dobzhansky-Muller model of hybrid incompatibility, and the snowball prediction in particular."
Environmental influences
Though the primary causes of hybrid incompatibility appear to be genetic, external factors may play a role as well. Studies focused primarily on model plants have found that the viability of hybrids can be dependent on environmental influence. Several studies on rice and Arabidopsis species identify temperature as an important factor in hybrid viability; generally, low temperatures seem to cause negative hybrid symptoms to be expressed while high temperatures suppress them, although one rice study found the opposite to be true. There has also been evidence in an Arabidopsis species that in poor environmental conditions (in this case, high temperatures), hybrids did not express negative symptoms and are viable with other populations. When environmental conditions return to normal, however, the negative symptoms are expressed and the hybrids are once again incompatible with other populations.
Lynch-Force model
Though a multitude of evidence supports the Dobzhansky-Muller model of hybrid sterility and speciation, this does not rule out the possibility that other situations besides the inviable combination of benign genes can lead to hybrid incompatibility. One such situation is incompatibility by way of gene duplication, or the Lynch and Force model (put forth by Michael Lynch and Allan Force in 2000). When gene duplication occurs, there is a possibility that a redundant gene can be rendered non-functional over time by mutations. From Lynch and Force's paper:"The divergent resolution of genomic redundancies, such that one population loses function from one copy while the second population loses function from a second copy at a different chromosomal location, leads to chromosomal repatterning such that gametes produced by hybrid individuals can be completely lacking in functional genes for a duplicate pair." This hypothesis is relatively recent compared to Dobzhansky-Muller, but has support as well.
Epigenetic influences
A possible contributor to hybrid incompatibility that fits with the Lynch and Force model better than the Dobzhansky-Muller model is epigenetic inheritance. Epigenetics broadly refers to heritable elements that affect offspring phenotype without adjusting the DNA sequence of the offspring. When a particular allele has been epigenetically modified, it is referred to as an epiallele A study found that an Arabidopsis gene is not expressed because it is a silent epiallele, and when this epiallele is inherited by hybrids in combination with a mutant gene at the same locus, the hybrid is inviable. This fits with the Lynch and Force model because the heritable epiallele, ordinarily not an issue in non-hybrid populations with non-epiallele copies of the gene, becomes problematic when it is the only copy of the gene in the hybrid population.
Study in Capsella shows that dosage of maternal small-interfering RNAs can contribute to hybrid incompatibility between closely related plant species.
See also
Hybrid inviability
References
Hybridisation (biology)
Breeding
Biology terminology | Hybrid incompatibility | [
"Biology"
] | 1,586 | [
"Behavior",
"Breeding",
"nan",
"Reproduction"
] |
59,627,314 | https://en.wikipedia.org/wiki/Biotic%20homogenization | Biotic homogenization is the process by which two or more spatially distributed ecological communities become increasingly similar over time. This process may be genetic, taxonomic, or functional, and it leads to a loss of beta (β) diversity. While the term is sometimes used interchangeably with "taxonomic homogenization", "functional homogenization", and "genetic homogenization", biotic homogenization is actually an overarching concept that encompasses the other three. This phenomenon stems primarily from two sources: extinctions of native and invasions of nonnative species. While this process pre-dates human civilization, as evidenced by the fossil record, and still occurs due to natural impacts, it has recently been accelerated due anthropogenic pressures. Biotic homogenization has become recognized as a significant component of the biodiversity crisis, and as such has become of increasing importance to conservation ecologists.
Overview
Homogenization versus differentiation
Homogenization is the process of assemblages becoming increasingly similar: the reverse is the process of assemblages becoming increasingly different over time, a process known as "biotic differentiation". Just as biotic homogenization has genetic, taxonomic, and functional components, differentiation can occur at any of these levels of organization.
Alpha and beta diversity
Understanding homogenization requires an understanding of the difference between alpha (α) and beta (β) diversity. Alpha diversity refers to diversity within a community: it addresses how many species are present. A community with high α diversity has many species present. Beta diversity compares multiple communities. For there to be high β diversity, two communities would have to have high α diversity but have different, unique species compositions.
Species introduction, extinction, and richness
When organisms are introduced to a habitat, be it naturally or artificially, overall species richness increases (assuming no other species are simultaneously lost). Similarly, when species become extinct, species richness decreases, once again assuming no other alterations to the assemblage. As such, when there is net increase in species richness, a common misconception is to assume that differentiation has occurred. This, however, may or may not be the case. While an increase in species richness does indicate an increase in α diversity, homogenization and differentiation specifically address β diversity.
Positive relationships with richness
While it may seem counterintuitive, there are times when increased species richness (α diversity) also leads to increased homogenization. If we imagine an example of two communities: community one contains four species (A, B, C, and D). Community two contains three species (C, D, and E). While there is overlap between these two communities, they are certainly different. However, if community two undergoes drastic change where E becomes extinct while A and B are simultaneously introduced, it now demonstrates higher species richness (greater α diversity), because there are now four species present instead of three. Yet, at the same time, communities one and two have become identical, removing any β diversity: they have homogenized. This particular trend is frequently observed in studies of biotic homogenization.
Sometimes decreased species richness can lead to greater β diversity and differentiation. If, in the example above, community one had lost species D and community two had lost species C, both communities would have lower α diversity because each would have one less species. However, the two communities would have no species in common, which would dramatically increase the β diversity, leading to differentiation.
Negative relationships with richness
In some cases, increased α diversity could theoretically lead to increased β diversity and differentiation. When we return to the previous example, community one still contains four species (A, B, C, and D) and community two contains three (C, D, and E). This time, C goes extinct in community two, but F and G are introduced at the same time. Community two now has greater richness and therefore greater α diversity. It also only now has one species in common with community one instead of two species. The two communities are now more different from each other than they were initially, indicating greater β diversity and therefore biotic differentiation.
Decreased richness could also lead to homogenization. If A were to go extinct in community one and E were to go extinct in community two, then both communities would have lower richness, since they both would be out one species. There would also be greater overlap in species composition between the two communities, indicating lost β diversity and increased homogenization.
Pressures leading to homogenization
Homogenization can result from either anthropomorphic or natural pressures. Many cases of species introductions are the result of either unintentional or intentional introduction of species by humans, be it for the pet trade, recreation, or agriculture. Urbanization can also have profound impacts on biota, leading to changes in assemblages. Natural selection and other evolutionary forces that lead to extinction can also potentially lead to homogenization. Sometimes, previously isolated populations can become exposed to each other naturally. Species interactions can also cause local extinctions, be the relationship predatory or pathogenic.
Components
Genetic
Genetic homogenization refers to the underlying molecular processes involved in biotic homogenization. It typically results from hybridization with non-native species, leading to decreased variation in the gene pool. These hybridization events may be either interspecific or intraspecific. Genetic homogenization can be analyzed in terms of allelic frequencies, which is accomplished through a comparison of how common specific genotypes are. If an allele occurs at a similar frequency between two populations, then there is greater homogenization present. Other evolutionary forces such as founder effects and bottleneck effects can also lead to genetic homogenization.
Taxonomic
Taxonomic homogenization is perhaps the most well-known and broadly studied component of biotic homogenization, and the two terms are often used interchangeably. It is most strictly defined as a loss in β diversity, meaning that multiple communities are increasing in taxonomic similarity over time. A common misconception with taxonomic homogenization is that it represents a loss in α diversity, or that it leads to decreased species richness. However, assemblages under taxonomic homogenization may actually display an increase in α diversity, a phenomenon that has been observed in plant, animal, and microbial groups.
Functional
Functional homogenization refers to the increase in similarity of function across a community: that is, similarity in the roles filled by the species. In an ecosystem that has undergone functional homogenization, there are increased species that fill the same functional role or niche, with fewer species occupying unique niches.
Analysis
Measuring biotic homogenization ultimately requires measuring β diversity. Taxonomic homogenization is typically studied by comparing two species pools that may be separated spatially, temporally, or both. Researchers can choose to use extant pools only or pools containing both extant species and reconstructed historical species. It is not unusual to compare relationships between α diversity and β diversity in a population.
Examples
Most studies of biotic homogenization have typically focused on fishes and vascular plants. More recently, however, homogenization has been demonstrated in other taxonomic groups.
Fossil Record
The fossil record gives multiple prehistoric examples of biotic homogenization. For example, the Panamanian land bridge between North and South America allowed previously isolated assemblages to homogenize. However, prehistoric rates of homogenization were at a far slower rate than they are currently. Additionally, organisms have been able to move far greater distances due to anthropomorphic impacts than they ever have done naturally.
Animals
Birds
Both taxonomic and functional homogenization have been investigated in birds. Certain island studies have demonstrated that on a small spatial scale, that avian taxonomic homogenization occurs far more rapidly than it does on a larger spatial scale. In France, communities have been recorded as becoming increasingly functionally similar over the course of two decades. Interestingly, in other French studies, it has been noted that there is not a temporal relationship between functional and taxonomic homogenization, a trend that had been observed in freshwater fishes. In urban landscapes, the introduction of non-native species such as rock doves and European starlings has led to increased homogenization of urban avian communities. Many species considered "urban exploiters" also contribute to biotic homogenization in urban environments, in part due to their ability to utilize anthropogenic resources. There have been predictions that avian taxonomic homogenization is occurring on the global scale, which could lead to future mass extinctions of avifauna.
Mammals
Ungulates were studied at both a global and local scale over a span of forty years, ending in 2005. On a global scale, it was found that homogenization had increased by 2%, and that introductions contributed more to this change than did extinctions. In a more localized study in South Africa, homogenization increased by 8%. In this example, species richness increased as homogenization increased.
Fishes
Freshwater fishes were among the first taxonomic groups to be used in homogenization studies, and trends have been observed on several continents. Homogenization in freshwater fishes typically stems from stocking of nonnative fishes for recreational purposes. In a more specific example, there was a 2015 study in Chile, where freshwater systems support diverse assemblages of endemic fishes. In a comparison of 201 watersheds that analyzed changes in similarities over 200 years, approximately 65% of comparisons demonstrate that the watersheds are undergoing homogenization.
Insects
While there have been fewer studies of biotic homogenization in insects compared to other taxonomic groups, there is evidence that it exists in multiple taxa. According to a 2015 study that examined bees, hoverflies, and butterflies, the extent to which taxonomic homogenization occurs varies with taxa, country, and spatial scale. In the three European countries that were included in the study, hoverflies had homogenized in all of the countries while bees and butterflies only homogenized in two countries. The scale at which homogenization occurred also varied between taxonomic groups.
Amphibians and reptiles
There has been relatively little research on homogenization in the herpetofauna, and according to a 2006 study, introduction of nonnative reptiles has not led to homogenization of reptilian communities in Florida. However, in Central America, Batrachochytrium dendrobatidis, which is pathogenic to amphibians, has led to selective extinction of certain taxa, which in turn has resulted in homogenization of certain amphibian assemblages. In addition to this more natural example of homogenization, there is evidence that there is amphibian homogenization of human-impacted environments around the world.
Plants
Anthropomorphic impacts on plants have been complex, with overall species richness of flora increasing over the course of human history. Additionally, there have been significantly more introductions on the continental scale than there have been extinction of endemics, increasing overall species richness and α diversity. However, β diversity has decreased in some circumstances, resulting in homogenization effects.
Microorganisms
Agriculture in the Amazon river basin has been connected to an increase in α diversity but a decrease in β diversity of bacteria. This trend is likely due to the loss of endemic species that have limited ranges being replaced by tolerant, generalist species.
Implications
Ecology and Evolution
Community composition, rather than richness, plays the more crucial role in maintaining the ecosystem. Due to the fact that the study of biotic homogenization is still relatively new, the implications of homogenization on the environment are still not entirely clear and it is possible that its impacts may not be all negative. Further research is required to determine the extent of its impact on the ecosystem. However, as ecosystems become increasingly similar and simplified, there is concern that the resilience of the assemblages against stressful events will be limited. Indeed, the more limited an assemblage becomes on functional, taxonomic, and genetic levels, the more constrained that assemblage is in its ability to evolve. Natural selection acts on diversity between individuals and species, and if that diversity does not exist, communities are severely limited when it comes to future evolutionary paths.
Conservation
Limiting biotic homogenization ultimately relies on limiting its sources: species invasion and extinction. Because these are largely rooted in human activity, if conservation is to be successful, it is necessary to reduce the degree to which people cause invasions and extinctions. Since biotic homogenization is still a relatively new area of study, increased education about both its mechanism and impact could potentially be effective as well. If we are to improve our understanding of the field, it is necessary to increase the scale of our knowledge of its spatial, temporal, geographic, and taxonomic components. There is a disproportionate number of studies in taxonomic homogenization, with relatively few in functional homogenization, which could have greater ecological implications. Increased study into functional homogenization could give insight into conservation needs. These gaps in the literature may, however, soon be filled. The study of homogenization is increasingly gaining attention in ecological circles, with the number of studies quantifying its effects increasing exponentially between the years of 2000 and 2015.
References
Biodiversity | Biotic homogenization | [
"Biology"
] | 2,722 | [
"Biodiversity"
] |
59,627,318 | https://en.wikipedia.org/wiki/Condition-dependent%20signaling | Condition-dependent signaling is a component of sexual selection. Its exact definition remains elusive due to the vagueness of the terms "condition" and "signaling". It examines which conditions favor the extravagant displays and ornaments, or signals, some organisms poses, despite their lack of evolutionary value in terms of fitness.
Condition-dependent signaling can affect individual mating tactics and depend on an individual's size, age, or other physical factors, such as a more fit individual being able to produce a stronger call than its less fit cohort. It can also impact the signaling choices of organisms based on the environment around them, like vocalizations that are more favorable in lower density environments.
Background
It is energetically expensive to produce a sexual signal. In some organisms the sexual signal may also have costs in terms of predation. For example, the ornate tail of a peacock makes it more difficult to hide and it also impedes flight. There are also different sexual phenotypes which may change the method of attempted copulation.
There may be several male reproductive phenotypes within a species and the phenotype that is manifest may be determined by a number of factors. For example, some phenotypes may employ a more aggressive and direct mating tactic while other phenotypes may use less traditional methods, as is the case with bluegill sunfish, where males use a "sneaking" tactic to find mating opportunities. Previous research has shown a great plasticity in sexual signals based on conditional qualities such as food availability, body condition, environmental conditions, population dynamics, and sexual displays. Condition dependent signaling is an important part of sexual selection theory.
For example, if an organism under selection where the sexual signals will not be as effective or they are in an environment lacking in energy, they may allocate less energy toward sexual selection. Condition dependent signaling research seeks to understand the true plasticity of sexual traits and determine if they may be more or less favored under different types of environmental stress.
Acoustic Calling
Individual tactics have been difficult to determine on a case-by-case basis, so research continues to examine the conditions and correlate it to changes in the mating tactics. Acoustic calling is a common mating tactic which can be affected by food availability, and female presence.
Food Availability
In one study researchers conducted an experiment to better understand condition dependent signaling of acoustic calling in relation to food availability. They studied crickets in the wild where they supplemented the experimental groups food supply to see if that would allow the males to allocate more energy toward calling. In comparison to the males in the control group, where the food had not been supplemented, the males in the experimental group were able to call more frequently. The food supplementation had an effect on the frequency of calls however the call itself remained consistent between the experimental and control group. This higher frequency of calls was effective in increasing the attraction of female crickets. This study concluded that condition dependent signaling is an imperative part of how females select their male partners in natural conditions.
Weight and female presence
Acoustic calling may be affected by an organism's physical characteristics which can be affected in turn by the environmental condition. In areas of food and water abundance the organisms may be healthier and better able to allocate more resources toward producing the acoustic calls. Another experiment examining vocalization studied tree frogs. The researchers recorded the calls of the male frogs in two different conditions. In one condition females were present and in the other they were absent. Both weight and condition affected the male frog's ability to call. The smaller males and the males that were in the best condition showed higher plasticity.
Effect of phenotype and mating tactics
In many species there are different mating tactics and they are displayed through multiple reproductive behavioral phenotypes and the different phenotypes have different advantages. These phenotypes, which have different sexual signaling tactics, are selected with consideration to the organism's environmental conditions. If a species energetic reserves need to be conserved for a function other than signaling than the energetically low-cost phenotypes may be selected for, while in times of high energy a less energetically conservative tactic may be favored. There may be a dominant mating tactic that is used by the majority of the males. There could also be alternative mating phenotypes that are employed in different conditions that favor an alternative tactic
Satellites
For example, Satellite males are males that will locate themselves near another male making a call and attempt to intercept the mate that the calling male attracts in order to copulate. In a study examining satellite males among green tree frogs the frogs were shown to switch between satellites and caller depending on the conditions around them. In a high call density, more callers would switch to satellite in order to benefit from the calls being produced but if call density decreased satellites would switch to calling.
Sneakers
The bluegill sunfish is a striking example of using an alternative mating tactic in conditions were the smaller males are not favored by the direct method. There is a direct method in this species dependent on typical sexual signaling such as size and coloring and they are referred to as 'Parentals'. However, another method used by some less traditionally favorable males of the species is to disguise themselves as the female of the species in order to sneak past the more traditionally competitive males in order to copulate and fertilize the female. They are referred to as Sneakers. This species also has Satellites. Satellites and Sneakers use the alternative method of female mimicry and sneaking to outcompete the Parental competitors who use a courting and guarding tactic.
References
Sexual selection | Condition-dependent signaling | [
"Biology"
] | 1,126 | [
"Evolutionary processes",
"Behavior",
"Sexual selection",
"Mating"
] |
59,627,348 | https://en.wikipedia.org/wiki/Temperature-size%20rule | The temperature-size rule denotes the plastic response (i.e. phenotypic plasticity) of organismal body size to environmental temperature variation. Organisms exhibiting a plastic response are capable of allowing their body size to fluctuate with environmental temperature. First coined by David Atkinson in 1996, it is considered to be a unique case of Bergmann's rule that has been observed in plants, animals, birds, and a wide variety of ectotherms. Although exceptions to the temperature-size rule exist, recognition of this widespread "rule" has amassed efforts to understand the physiological mechanisms (via possible tradeoffs) underlying growth and body size variation in differing environmental temperatures.
History
Relation to Bergmann's rule
In 1847, Carl Bergmann published his observations that endothermic body size (i.e. mammals) increased with increasing latitude, commonly known as Bergmann's rule. His rule postulated that selection favored within species individuals with larger body sizes in cooler temperatures because the total heat loss would be diminished through lower surface area to volume ratios. However, ectothermic individuals thermoregulate and allow their internal body temperature to fluctuate with environmental temperature whereas endotherms maintain a constant internal body temperature. This creates an inaccurate description of observed body size variation in ectotherms since they routinely allow evaporative heat loss and do not maintain constant internal temperatures. Despite this, ectotherms have largely been observed to still exhibit larger body sizes in colder environments.
Formulation of the rule
Ray (1960) originally examined body sizes in several species of ectotherms and discovered that around 80% of them exhibited larger body sizes in lower temperatures. A few decades later, Atkinson (1994) performed a similar review of temperature effects on body size in ectotherms. His study, which included 92 species of ectotherms ranging from animals and plants to protists and bacteria, concluded that a reduction in temperature resulted in an increase in organism size in 83.5% of cases. Atkinson's findings provided support for Ray's published works that ectotherms have an observable trend in body size when temperature is the primary environmental variable. The results of his study prompted him to name the increase in ectothermic body size in colder environments as the temperature-size rule.
Tradeoffs as possible underlying mechanisms
Life history model
Life history models highlighting optimal growth patterns suggest that individuals assess the environment for potential resources and other proximate factors and mature at a body size that yields the greatest reproductive success, or highest percentage of offspring surviving to reach reproductive maturity.
Size at maturity
Environmental temperature is one of the most important proximate factors affecting ectotherm body size because of their need to thermoregulate. Individuals that have been observed to follow the temperature-size rule have slower growth rates in colder environments, yet they enter a period of prolonged growth that yields larger adult body sizes. One proposed explanation for this involves a trade-off in life history traits. Ectotherms experience longer daily and seasonal activity times in warmer climates versus cooler climates, however, the increase in daily activity time is accompanied by higher infant and adult mortality rates due to predation. Under these environmental conditions, some individuals occupying these warmer climate environments will mature at smaller body sizes and undergo a shift in energy allocation of all acquired energy resources to reproduction. In doing so, these individuals sacrifice growth to larger adult body sizes to ensure reproductive success, even if the trade-off results in smaller offspring that have increased mortality rates.
Reproduction
Ectotherms occupying colder environments, such as mountain ranges or other areas of higher elevation, have been observed to invest in reproduction at larger adult body sizes due to a prolonged growth period. These populations of ectotherms are characterized as having smaller clutches of larger eggs, favoring a greater reproductive investment per egg and enhances offspring survival rates. Individuals occupying warmer environments experience a trade-off between body size and overall reproductive success that many individuals occupying colder environments do not, hence, prolonging growth to yield greater reproductive success in colder environments could potentially be an underlying mechanism for why a large percentage of ectotherms exhibit greater body sizes in colder environments. However, a sufficient explanation for this observable pattern has yet to be produced.
Investigation
Supporting evidence
In the soil nematode, Caenorhabditis elegans, adult body size reared at 10°C was approximately 33% greater than individuals grown at 25°C.
Ashton & Feldman's (2003) study concluded that chelonians (turtles) follow the temperature-size rule with 14 of 15 sp. decreasing in size with increasing temperature.
Body size in the larval ant lion, Myrmeleon immaculatus, has been observed to follow Bergmann's size clines in response to latitudinal changes. However, when reared in high and low temperatures, body size was not affected. Food availability was the driving mechanism behind recorded body size variation.
Hatchlings of Lacerta vivipara, now known as Zootoca vivipara, from high elevation populations were raised in outdoor enclosures at high and low altitudes. They were observed to have faster growth rates and higher mortality rates in the low altitude enclosures. Although there was no mention of exhibiting body size patterns in accordance with the temperature-size rule, the faster growth rates and higher mortality imply that lizards in the high altitude enclosures had slower growth rates and lower hatching mortality, a routine pattern indicative of species that conform to the possible temperature-size rule tradeoff.
Eastern fence lizards, Sceloporus undulatus, exhibit delayed maturation at larger body sizes, a trend consistent with the temperature-size rule.
Exceptions
The grasshopper, Chorthippus brunneus, is a high temperature specialist (or stenotherm) that matures to larger body sizes at high temperatures, making it an exception to the temperature-size rule.
Juvenile survivorship in Sceloporus graciosus is not found to be higher in cooler environments, leading the species to exhibit body size clines inconsistent with the temperature size rule.
In the same study that Ashton & Feldman provided evidence that chelonians exhibit body size clines consistent with the temperature-size rule, they also provided evidence that squamates (lizards and snakes) trend towards larger body sizes in warmer environments (40 out of 56 species increased in size with temperature). This was the first study to show a major group of ectotherms that show the converse to the temperature-size rule.
Notes
The supporting evidence and the exceptions to the temperature-size rule listed above are only a few of the potential supporting/opposing evidence available for the temperature-size rule. Each was provided to support the claim that patterns of body size observed in variable environments are not 100% predictable and more research is required to identify and understand all of the mechanisms responsible.
References
Evolutionary biology
Extended evolutionary synthesis | Temperature-size rule | [
"Biology"
] | 1,410 | [
"Evolutionary biology"
] |
59,627,354 | https://en.wikipedia.org/wiki/Sexual%20selection%20in%20flowering%20plants | Sexual selection is natural selection arising through preference by one sex for certain characteristics in individuals of the other sex. It is a common concept in animal evolution but, with plants, it is often overlooked because many plants are hermaphrodites. Flowering plants have many sexually selected characteristics. For example, flower symmetry, nectar production, floral structure, and inflorescences are among the secondary sex characteristics acted upon by sexual selection. Sexual dimorphisms and reproductive organs can also be affected by sexual selection.
Mechanisms of sexual selection
There are two main mechanisms of sexual selection in flowering plants, one being intra-sexual competition and the other being female mate choice. Intra-sexual selection is responsible for much of floral evolution and diversification. Intrasexual selection, with the help of pollinators, has also led to some of the most remarkable examples of exaggerated traits of among hermaphroditic plants. Similarly, sexual dimorphism has probably been involved in the evolution of sexual dimorphism in floral traits of dioecious plants, and likely also in the evolution of secondary sexual dimorphism through genetic correlations with floral traits. Sexual selection through female choice is perhaps a more difficult concept to apply to plants. There is evidence that females (or the female function of hermaphrodites) exercise choice, especially during fertilization. These two mechanisms are the main driving forces of sexual selection in flowering plants.
Symmetry and structure
Floral symmetry is often acted on by sexual selection. Floral characters are often subject to strong directional selection from pollinators, and this may disrupt developmental homeostasis in flowers that can develop into large degrees of fluctuating asymmetry. Fluctuating asymmetry in floral traits may lead to sexual selection in plants if pollinators visit symmetrical flowers in an assortative manner. Numerous studies have shown that pollinators preferentially visited more symmetrical floral patterns in flowers, and there are several believed reasons why this pollinator preference exists. First, the preference may be present due to positive reinforcement. From experience, pollinators may learn that asymmetrical flowers provide a lesser award than symmetrical ones. Second, pollinators with sensory biases could be predisposed to select symmetrical flowers. This pollinator preference can lead to symmetrical flowers that are fertilized more often. This increase in fertilization frequency increases the amount of seeds produced, and results in an increased production of offspring with symmetrical, attractive flowers.
Sexual dimorphisms
There are numerous examples of sexual dimorphisms in flowering plants. Sexual dimorphic differences include bud abortion, flower size, flower number per plant, floral longevity, nutrient content of flowers, nectar production, flowering phenology and periodicity, floral fragrances, floral defense against herbivory, and various inflorescence characteristics including total flower number, daily display size, and inflorescence architecture. In animal-pollinated species, these differences affect pollinator visitation, competition for mates, and the evolution of sexual dimorphisms. However, there are constraints placed on animal-pollinated species, because too much divergence could interfere with mating success if pollinators are more attracted to one sex than the other, or if the sexes attract different pollinators. Such constraints are absent from wind-pollinated plants, and the contrasting biophysical requirements for pollen dispersal and pollen capture have led to striking cases of sexual dimorphism in plant architecture and flower production in some species. Below are some specific examples of sexual dimorphisms in flowering plants.
Inflorescences
Inflorescences can be acted on by sexual selection in many ways, and commonly include arrangement, number, and size. For example, male inflorescence in plants often produce more flowers than females . Furthermore, pollen export and ultimately paternity, often increases with flower number, even for plants with hermaphroditic flowers. Retention of older flowers with no pollinator rewards can lead to increased pollinator visitation rate and increased pollen removal. Studies suggest that there has been selection for increased pollen delivery, achieved through greater inflorescence size, and it seems probable that male-male competition is commonly part of that selection pressure.
Corolla
Corollas are the petals of flowers, and also face sexual selection. Traits such as color, shape, size, and symmetry are often faced by sexually selected pressure. One example is that male flowers are often larger than female flowers, at least in some species. Although this is presumably achieved through resource allocation mechanisms, it is unlikely that resource allocation from lower cost of androecium than gynoecium leading to higher expenditure on corolla in males, is a general and complete explanation of the size differences. Some corolla enlargement may arise by means of selection on correlated characters such as pollen production. However, it is likely that male competition often contributes directly to the evolution of large male corollas, especially where pollen availability is not limiting.
Nectar production
The flowers of most angiosperms produce nectar. Nectar production (sugar concentration, quantity of nectar, timing relative to floral gender phases) is different for every flowering plant that produces nectar, and has many different selective forces acting upon it. There is no single evolutionary force that drives nectar production, but it is believed that sexual selection plays a major role. Studies have supported the idea that sexual selection is a probable explanation for at least some species with gender-biased nectar production. For example, gender-biased expression of nectar is often accompanied by a similarly biased expression of other floral characteristics. A specific example comes from the flowers of Impatiens capensis, and how they show increased longevity of the more-rewarding male phase. In other species, petals can be seen to wilt notably during the less- rewarding female phase or they change color as they pass into the less-rewarding female phase. More evidence for sexually selected nectar production relies on specific behaviors of the pollinators. If sexual selection is currently maintaining gender-biased nectar production, pollinators must be able to distinguish between male and female phase flowers. They also must visit preferentially flowers of the more-rewarding phase. For species that have discriminating pollinators, increased rewards can result in increased mating success, which would allow nectar to be a sexually selected trait.
Reproductive organs
The stamens, collectively known as the Androecium, are often faced by the pressures of sexual selection. This is particularly evident when pollen is produced; there may be several sources of sexual selection on the ways that pollen is presented to pollen vectors. Because pollen is packaged in units that ensure that several to many pollen grains travel together as in pollinia, polyads, viscin threads, etc., pollen donors may be able to monopolize stigmas and the associated ovules by blocking access by other males, unless selection also favors compensating stigma enlargement. Furthermore, when pollen germination depends on some minimum number of pollen grains to overcome stigmatic inhibition, which is a mechanism that heightens male competition, there may be selection for large pollen dispersal units or certain other pollen-dispensing mechanisms. If pollinator visits are few, then there is selection to package pollen in a way that all of it can be removed by one visit. When repeated pollinator visits are typical, there may be selection for various temporal patterns of pollen presentation and various methods of pollen dispensing. Variation in stamen length, both within and among flowers influences pollen dispersal and potential male reproductive success. Increasing the opportunity for paternity by distributing pollen among pollinators may take different routes in different systems, and any of these possibilities can be viewed in a sexual selection context . The gynoecium is also affected by sexual selection. Every part from the ovaries, styles, stigma, and carpels can be faced with the pressures of sexual selection. In ovule packaging, the intensity of pollen competition depends in part on the number of pollen grains relative to the number of ovules. Although many factors may contribute to determining ovule number, one way for females to increase the level of pollen competition is to decrease ovule number while maintaining stigma size. The evolution of functional syncarpy (assuming no other attendant changes) presumably is a simultaneous increase in the number of ovules accessible from one stigma, which tended to decrease the intensity of pollen competition, and a concentration of pollen deposition on a single stigma, which tends to increase pollen competition. Further increases in pollen competition could be brought about by an increase in pollen delivery (through change of pollinator, increased attractiveness of floral display, or rewards), a decrease in ovule number or stigma size, changes in temporal patterns of stigma receptivity, or changes in the competitive environment of the carpel .
References
Sexual selection
Evolution of plants | Sexual selection in flowering plants | [
"Biology"
] | 1,805 | [
"Evolutionary processes",
"Behavior",
"Plants",
"Evolution of plants",
"Sexual selection",
"Mating"
] |
59,627,363 | https://en.wikipedia.org/wiki/Cancer%20selection | Cancer selection can be viewed through the lens of natural selection. The animal host's body is the environment which applies the selective pressures upon cancer cells. The most fit cancer cells will have traits that will allow them to out compete other cancer cells which they are related to, but are genetically different from. This genetic diversity of cells within a tumor gives cancer an evolutionary advantage over the host's ability to inhibit and destroy tumors. Therefore, other selective pressures such as clinical treatments and pharmaceutical treatments are needed to help destroy the large amount of genetically diverse cancerous cells within a tumor. It is because of the high genetic diversity between cancer cells within a tumor that makes cancer a formidable foe for the survival of animal hosts. It has also been proposed that cancer selection is a selective force that has driven the evolution of animals. Therefore, cancer and animals have been paired as competitors in co-evolution throughout time.
Natural selection
Evolution, which is driven by natural selection, is the cornerstone for nearly all branches of biology including cancer biology. In 1859, Charles Darwin's book On the Origin of Species was published, in which Darwin proposed his theory of evolution by means of natural selection. Natural selection is the force that drives changes in the phenotypes observed in populations over time, and is therefore responsible for the diversity amongst all living things. It is through the pressures applied by natural selection upon individuals that leads to evolutionary change over time. Natural selection is simply the selective pressures acting upon individuals within a population due to changes in their environment which picks the traits that are best fit for the selective change.
Selection and cancer
These same observations that Darwin proposed for the diversity in phenotypes amongst all living things can also be applied to cancer biology to explain how selection drives change in the population of cells within a tumor over time. Therefore for the purpose of cancer evolution the body of the organism is the environment, and changes in the environment, whether via natural processes or clinical therapies, apply the selective pressures upon cancer that can drive a selective adaptation in cancerous tumor cells.
Cancers as a product of host evolution
Cancer is a very ancient pathology that emerged with multicellular organisms. Hosts, therefore, have had billions of years to co-evolve with cancers. Over evolutionary time hosts develop an increasing number of cancer suppressors (e.g. cytotoxic lymphocytes, Natural Killer cells, suppressor gene such as p53 copy number of those genes. Cancers are the outcome of cells that escape these evolved suppression mechanisms.
Diversity is a selective advantage
Cancer is a disease which is highly diverse not only its pathology, but in the initiation and progression from non-cancerous tissue to malignant tumor tissue . Cancer is considered to be stochastic in nature, in that there are many variables and probabilities that contribute to how a cell or tissue progresses from a state of non-cancerous, to cancerous, and eventually to metastasis. Cancer differs from many other diseases due to the uniquely long lifespan of the disease which contributes to the diversity of cancer cells both within a tumor and between related tumors in a host.
Tumor heterogeneity
As time passes cancerous tumors can progress in genetic diversity amongst clonal cells due to the ability to accumulate changes over time, until the tumor reaches homeostasis thus allowing for the spread of the disease throughout the body of a host. Overlap this pathway with all of the other developmental pathways and possible events that can lead to the same outcome of metastasis, and it becomes apparent that cancer has a unique ability to find a way to progress into its cancerous phenotype. Therefore, from the moment of initiation putting cells or tissues down a pathway towards metastasis the majority of tumor cells will accumulate mutations that increases genetic diversity within the tumor (intra-tumor genetic heterogeneity). Not only can tumors be composed of genetically diverse cells, it can also lead to inter-tumor heterogeneity meaning that related tumors within the same host are genetically different. This tumor heterogeneity gives a selective advantage to the best fit clonal and sub-clonal cells of a tumor. Due to the heterogeneity and the unchecked proliferation of tumor cells, cancer is given a selective advantage not only over non-cancerous cells, but also against selective pressures that choose against it, such as pharmaceutical and clinical therapies, and also the host's immune system.
Resistance
Due to its diverse nature, cancer has been able to evolve very defined and specific mechanisms to resist selective pressures. The goal of selective pressures upon cancer is to rid the disease of its diversity and thus in doing so forcing it back into an initial less harmful, more easily treatable, less diverse, non cancerous neoplastic state in which it is considered not to be lethal. A neoplastic state or neoplasm is simply an abnormal growth of tissue which can range from a harmless non-cancerous mole to a cancerous tumor. Cancer can circumvent negative selective pressures due to its ability to accumulate mutations that cause genetic diversity in tumor cells as the cells proliferate. Cancer seems to have evolved a propensity for, or at the very least, a selection for fitness. This is demonstrated in the ability for tumors which are undergoing large amounts of mutations to find a way for the cells composing the tumor to survive and to produce cellular offspring which are better fit for survival. Therefore, cancer initiation and progression have to be highly conserved evolutionarily or a tumor would dissociate merely due to inordinate volume of mutations that occur within it.
Evolution in animals driven by cancer
Another interesting way to look at cancer evolution is not through the lens of how selective pressures shape the disease throughout its time spent within an organism, but rather to think of cancer as a selective force itself shaping the evolution of the populations of animal hosts. By taking this approach cancer selection would be defined in the same terms that natural selection and artificial selection are defined. This means that like natural and artificial selection, cancer selection would be defined as a selective force that is capable of driving population diversity and over time lead to evolution.
Cancer is selfish
Cancer is often defined as being selfish, in that it is composed of selfish cell lines which produce progeny that have higher fitness and reproductive success than parental cells which allow them to out compete other clonal cells. This increase in fitness (cancer progression) is of course detrimental to the host within which cancer resides. Therefore, one could possibly look at cancer and animal hosts to be intertwined in the complicated dance known to biologists as co-evolution. This theory would propose that as animals evolve new morphological traits and life-history behaviors they become more susceptible to developing cancer. Therefore, cancer gains the evolutionary advantage over animals because of newly evolved animal traits that it can select against or for its own survival. This then places the selective pressure back upon animal species to evolve or forever succumb to cancer selective pressures. Most recently it has been theorized that all of the morphological and life history diversity seen today in animals, is the result of the uncountable deaths caused by cancer in ancestral animal lineages.
Examples
Cancer is a disease with a long lifespan. Therefore, as animals evolved into bigger and more complex organisms with longer lifespans themselves their morphologies were highly restricted by the need to adapt a resistance to the negative selective pressures that cancer placed upon them. For cancer cells to thrive they must be able to proliferate unchecked and uncontrolled within the tissues of their animal hosts. Therefore, animals have adapted to cancer selection by evolving tumor suppressing genes. These genes help inhibit the initiation and progression of cancerous cells.
References
Biological interactions
Cancer
Cancer research
Natural selection | Cancer selection | [
"Biology"
] | 1,566 | [
"Evolutionary processes",
"Behavior",
"Biological interactions",
"Natural selection",
"nan",
"Ethology"
] |
59,627,488 | https://en.wikipedia.org/wiki/Betalipothrixvirus%20hveragerdiense | Betalipothrixvirus hveragerdiense (SIFV) is an archaeal virus, classified in the family Lipothrixviridae within the order Ligamenvirales. The virus infects hypethermophilic and acidophilic archaeon Sulfolobus islandicus.
SIFV has a linear double-stranded DNA genome of 40,852 bp, which is the largest among characterized lipothrixviruses. The virions are enveloped filaments, nearly 2 micrometers in length. The nucleocapsid is formed from two paralogous major capsid proteins, which tightly wrap around the dsDNA genome; notably, dehydration of the genomic DNA by the major capsid proteins transforms the B-form DNA into A-form DNA.
Life cycle
SIFV virions assemble inside the cell. Binding of the major capsid protein dimers to the linear dsDNA genome lead to the assembly of nucleocapsids, which are subsequently enveloped intracellularly through an unknown mechanism. SIFV and probably other lipothrixviruses are lytic viruses. Virion release takes place through pyramidal portals, referred to as virus-associated pyramids (VAPs). Unlike in the case of some other archaeal viruses (e.g., rudiviruses and turriviruses), the SIFV VAPs have a hexagonal base (i.e., constructed from six triangular facets). The VAPs can be as large as 220 nm at the base and are constructed from a single SIFV-encoded protein of 89 aa. Expression of this protein in E. coli leads to VAP formation in the inner bacterial membrane.
References
Archaeal viruses
Ligamenvirales | Betalipothrixvirus hveragerdiense | [
"Biology"
] | 372 | [
"Virus stubs",
"Viruses",
"Archaea",
"Archaeal viruses"
] |
59,628,350 | https://en.wikipedia.org/wiki/Business%20Information%20System%20%28government%20service%29 | The Business Information System (BIS; , ) is a Finnish government service jointly maintained by the (PRH) and the Finnish Tax Administration providing an access to the Finnish Trade Register and the and an ability to file information for both agencies. The name is an abbreviation of the Finnish full name Yritys- ja yhteisötietojärjestelmä.
Searching companies in the Finnish Trade Register can be made with the name of the company or the Business ID (, ). The BIS database does not include the .
References
External links
Economy of Finland
Information systems | Business Information System (government service) | [
"Technology"
] | 115 | [
"Information systems",
"Information technology"
] |
59,630,222 | https://en.wikipedia.org/wiki/IBM%20Q%20System%20One | IBM Quantum System One is the first circuit-based commercial quantum computer, introduced by IBM in January 2019.
This integrated quantum computing system is housed in an airtight borosilicate glass cube that maintains a controlled physical environment. Each face of the cube is wide and tall. A cylindrical protrusion from the center of the ceiling is a dilution refrigerator, containing a 20-qubit transmon quantum processor. It was tested for the first time in the summer of 2018, for two weeks, in Milan, Italy.
IBM Quantum System One was developed by IBM Research, with assistance from the Map Project Office and Universal Design Studio. CERN, ExxonMobil, Fermilab, Argonne National Laboratory and Lawrence Berkeley National Laboratory are among the clients signed up to access the system remotely.
From April 6 to May 31, 2019, the Boston Museum of Science hosted an exhibit featuring a replica of the IBM Quantum System One.
On June 15, 2021, IBM deployed the first unit of Quantum System One in Germany at its headquarters in Ehningen. On April 5, 2024, IBM unveiled a Quantum System One at the Rensselaer Polytechnic Institute, the first IBM quantum system on a university campus.
See also
IBM Eagle
IBM Quantum Platform
Timeline of quantum computing and communication
Superconducting quantum computing
Qiskit
References
External links
Official website
Quantum computing
Computer-related introductions in 2019
IBM computers | IBM Q System One | [
"Technology"
] | 283 | [
"Computing stubs",
"Computer hardware stubs"
] |
59,630,526 | https://en.wikipedia.org/wiki/Transition%20metal%20imido%20complex | In coordination chemistry and organometallic chemistry, transition metal imido complexes is a coordination compound containing an imido ligand. Imido ligands can be terminal or bridging ligands. The parent imido ligand has the formula NH, but most imido ligands have alkyl or aryl groups in place of H. The imido ligand is generally viewed as a dianion, akin to oxide.
Structural classes
Complexes with terminal imido ligands
In some terminal imido complexes, the M=N−C angle is 180° but often the angle is decidedly bent. Complexes of the type M=NH are assumed to be intermediates in nitrogen fixation by synthetic catalysts.
Complexes with bridging imido ligands
Imido ligands are observed as doubly and, less often, triply bridging ligands.
Synthesis
From metal oxo complexes
Commonly metal-imido complexes are generated from metal oxo complexes. They arise by condensation of amines and metal oxides and metal halides:
LnMO + H2NR → LnMNR + H2O
This approach is illustrated by the conversion of MoO2Cl2 to the diimido derivative MoCl2(NAr)2(dimethoxyethane), precursors to the Schrock carbenes of the type Mo(OR)2(NAr)(CH-t-Bu).
LnMCl2 + 3 H2NR → LnMNR + 2 RNH3Cl
Aryl isocyanates react with metal oxides concomitant with decarboxylation:
LnMO + O=C=NR → LnMNR + CO2
Alternative routes
Some are generated from the reaction of low-valence metal complexes with azides:
LnM + N3R → LnMNR + N2
A few imido complexes have been generated by the alkylation of metal nitride complexes:
LnMN− + RX → LnMNR + X−
Utility
Metal imido complexes are mainly of academic interest. They are however assumed to be intermediates in ammoxidation catalysis, in the Sharpless oxyamination, and in nitrogen fixation.
In nitrogen fixation
A molybdenum imido complex appears in a common nitrogen fixation cycle:
Mo•NH3 (ammine);
with the oxidation state of molybdenum varying to accommodate the number bonds from nitrogen.
References
Coordination chemistry | Transition metal imido complex | [
"Chemistry"
] | 520 | [
"Coordination chemistry"
] |
59,632,474 | https://en.wikipedia.org/wiki/Oibora-Asakura%20Sue%20Ware%20Kiln%20Site | The is an archaeological site containing a group of Nara period kilns located in the Akutami neighborhood of the city of Gifu in the Chūbu region of Japan. The site was designated a National Historic Site of Japan in 1979.
Overview
Ancient Mino Province was a major center for the manufacturing of Sue pottery from before the Nara period, and numerous ruins of ancient kilns have been found in the area around the border of the modern cities of Gifu, Toki and Kakamigahara. In the southern foothills of the Kakamigahara Mountains more than 130 Sue pottery kilns from the Nara and Heian periods are distributed. The Oibora-Asakura site is located on the western edge of this area, on the northern and southern slopes of the Suwa Mountains near the Nagara River. In 1967, a Sue pottery engraved with the words "Mino Kuni" was excavated from the remains of the Asakura kiln at the southern foot of the mountain, and more than four kiln sites were later discovered. In 1977, another site containing a Sue pottery fragment stamped with the "Mino Province" mark was discovered from the Oibora kiln site at the northern foot of the mountain, and three kiln ruins were confirmed at this location. Both sites date from the latter half of the 7th century to the early 8th century and our 70,000 pottery shards were found. A ceramic stamp for making the "Mino Province" marking was also found at the Oibora site.
Some of the Sue pottery made at these sites have been discovered at various locations around Japan, including the site of the Heijō Palace in Nara, Ise Shrine in Mie prefecture and the Mino Kokubun-ji ruins.
The Oibora kiln site is about a ten minute walk from the "Higashi-Asakura" bus stop on the Gifu Bus from Meitetsu Gifu Station and the Asakura kiln site is about ten minutes from the "Suwayama housing complex" bus stop on the same route. Some of the excavated items from the Oibora kiln site are designated as Important Cultural Properties, and are at the Gifu City History Museum.
See also
List of Historic Sites of Japan (Gifu)
References
External links
Gifu Prefecture home page
History of Gifu Prefecture
Gifu
Historic Sites of Japan
Japanese pottery kiln sites | Oibora-Asakura Sue Ware Kiln Site | [
"Chemistry",
"Engineering"
] | 489 | [
"Kilns",
"Japanese pottery kiln sites"
] |
59,632,528 | https://en.wikipedia.org/wiki/Second%20neighborhood%20problem | In mathematics, the second neighborhood problem is an unsolved problem about oriented graphs posed by Paul Seymour. Intuitively, it suggests that in a social network described by such a graph, someone will have at least as many friends-of-friends as friends.
The problem is also known as the second neighborhood conjecture or Seymour’s distance two conjecture.
Statement
An oriented graph is a finite directed graph obtained from a simple undirected graph by assigning an orientation to each edge. Equivalently, it is a directed graph that has no self-loops, no parallel edges, and no two-edge cycles. The first neighborhood of a vertex (also called its open neighborhood) consists of all vertices at distance one from , and the second neighborhood of consists of all vertices at distance two from . These two neighborhoods form disjoint sets, neither of which contains itself.
In 1990, Paul Seymour conjectured that, in every oriented graph, there always exists at least one vertex whose second neighborhood is at least as large as its first neighborhood. Equivalently, in the square of the graph, the degree of is at least doubled. The problem was first published by Nathaniel Dean and Brenda J. Latka in 1995, in a paper that studied the problem on a restricted class of oriented graphs, the tournaments (orientations of complete graphs). Dean had previously conjectured that every tournament obeys the second neighborhood conjecture, and this special case became known as Dean's conjecture.
A vertex in a directed graph whose second neighborhood is at least as large as its first neighborhood is called a Seymour vertex.
In the second neighborhood conjecture, the condition that the graph have no two-edge cycles is necessary, for in graphs that have such cycles (for instance the complete oriented graph) all second neighborhoods may be empty or small.
Partial results
proved Dean's conjecture, the special case of the second neighborhood problem for tournaments.
For some graphs, a vertex of minimum out-degree will be a Seymour vertex. For instance, if a directed graph has a sink, a vertex of out-degree zero, then the sink is automatically a Seymour vertex, because its first and second neighborhoods both have size zero. In a graph without sinks, a vertex of out-degree one is always a Seymour vertex. In the orientations of triangle-free graphs, any vertex of minimum out-degree is again a Seymour vertex, because for any edge from to another vertex , the out-neighbors of all belong to the second neighborhood of .
For arbitrary graphs with higher vertex degrees, the vertices of minimum degree might not be Seymour vertices, but the existence of a low-degree vertex can still lead to the existence of a nearby Seymour vertex. Using this sort of reasoning, the second neighborhood conjecture has been proven to be true for any oriented graph that contains at least one vertex of out-degree ≤ 6.
Random tournaments and some random directed graphs graphs have many Seymour vertices with high probability.
Every oriented graph has a vertex whose second neighborhood is at least times as big as the first neighborhood,
where
is the real root of the polynomial .
See also
Friendship paradox
References
External links
Seymour's 2nd Neighborhood Conjecture, Open Problems in Graph Theory and Combinatorics, Douglas B. West.
Unsolved problems in graph theory
Conjectures | Second neighborhood problem | [
"Mathematics"
] | 661 | [
"Unsolved problems in mathematics",
"Mathematical problems",
"Conjectures",
"Unsolved problems in graph theory"
] |
59,633,251 | https://en.wikipedia.org/wiki/Borze%C8%99ti%20Petrochemical%20Plant | Borzeşti Petrochemical Plant (formerly GIP - Borzeşti Petrochemical Industrial Group) is an industrial complex consisting of five large-scale plants: Synthetic Rubber and Petrochemicals Complex, No. 10 Oil Refinery, Borzești Chemical Plant, Borzești Power Plant and Chemical Equipment Company, being the largest industrial complex in Bacău County and the largest unit of its kind in Romania, which covers an area of , with an average length of and a width of . It is located on the Trotuș Valley, on the northeastern outskirts of Onești (named between 1965 and 1990 Gheorghe Gheorghiu-Dej).
Its construction began in 1952 and the first plants were put into operation in 1956 at the No. 10 Oil Refinery.
On April 1, 1969, the three distinct plants on the industrial platform in Borzeşti merged into the giant "Petrochemical Industrial Group Borzeşti" complex, and in 1973 it was renamed the "Borzeşti Petrochemical Plant". The abandonment of the centralized management system of the Romanian economy in 1990 determined the reappearance of the distinct entities, thus the Petrochemical Platform was divided into the private companies: Carom Onești, Rafo, Chimcomplex, Întreprinderea Electrocentrale Borzeşti and Uton.
Emplacement
The space occupied by the petrochemical plant is located in the north-northeast of Onești, near the former village of Borzești. It stretches on the lower terraces of the Trotuș River in the valley of the confluence area with altitudes of and . It has a rectangular shape oriented north-east, southwest with an average length of and a width . The choice of place is motivated by the relatively flat levels of the terraced bridges, with passages dimmed by the colluvium, the presence of the Trotuş River water on the northern and north-eastern side, the existence of the communication ways.
History
In 1952, a team of geographers and urbanists headed by Mihail Florescu, Minister of Chemical Industry, went to the Trotuş Valley to establish the location of a city and a large industrial compound. In this team was also the geographer Vintilă M. Mihăilescu. It was preferred Onești because:
is located at the meeting place of Trotuș River () with its most important tributaries: Cașin River (), Oituz River () and Tazlău River ().
is situated at a convergence of roads in four main directions: towards Brașov via Târgu Secuiesc through the Oituz Pass; towards Târgu Ocna (with a branch to Slănic-Moldova), Comănești (with a branch to Moinești) and Miercurea Ciuc through Ghimes-Palanca Pass; towards Bacău, through the Tazlău subcarpathian depression (with a branch pointing to Moinești); towards Adjud, in the lower valley of the Trotuș River.
is seated in a well-populated area.
is set in a relief made up of a slab built of sandstone gravel in a thick blanket covered with clay, consisting of two terraces, a taller one and a lower one.
However, natural elements were not enough to achieve a medium-sized city (40 to 60,000 inhabitants). This is consistent with the French geographer Paul Vidal de La Blache in the sense that "the elements of the site have elements of fixation, whereas those of the situation (geographical position) are factors of progression, of development. The site receives the city, but it is the situation which vivifies it." Vidal's concept was also verified in the case of Onești, the potential regional elements were concentrated in the petrochemical plant: petroleum crude oil from Bacău Region oilfield, sodium chloride from Târgu Ocna mine. The energy base was completed with the methane gas transported through the trans-Carpathian pipeline Nadeș-Oituz Pass.
The location between Onești and of a large petrochemical industrial complex - approved by H.C.M. (Hotărârea Consiliului de Miniștrii) No. 1638/1952, an integral part of the measures taken by the Romanian Workers' Party for the development of Moldavia, proved to be optimal on technical, economical and social criteria, taking into account the amounts of considerable natural resources in the Trotuș basin. The same decision stipulated the need for the construction of a thermal power plant in Borzeşti, which was to supply the new industrial complex in Onesti with electric and thermal energy. The data in 1951 showed that the electricity demand in Moldova amounted to 1,350 million KWh for the year 1955, that is for 5.6 times more than the entire production of the first year of the 1951-1955 Five-Year Plan.
By the Decision of the Council of Ministers (H.C.M.) No. 1635/1952, it was envisaged that in the Bacău Region, Târgu Ocna Raion, the construction of Borzești Industrial Group and the related proletarian city, Onești. The industrial zone was built northeast of the former village of Borzești, between the railway and the Trotuș River, its surface exceeding that of other parts of the city. As a result of this decision, in 1952, the colonies for construction workers began to be built and then the foundations of the first apartment buildings. At the city and industrial sites have worked alongside construction workers assembled in colonies and common law detainees or political prisoners. Soon the city had the highest number of intellectuals per thousand inhabitants, and the average age was 28 years old.
The petrochemical plant was built in four stages: First stage (1952-1960), comprises the first works from the Borzești Thermal Power Plant (1952), the No. 10 Oil Refinery (by H.C.M .1683/1952), the Rubber Plant (H.C.M. 1498/1957) grouped on 610 ha; (1961-1965), the phenol, acetone equipments (1961), synthetic rubber (1963) and styrene-polystyrene (1964), the industrial platform exceeds 846 ha. In the third stage (1966-1970), works were started at Refinery II and the Poly-isoprenic factory. In the fourth stage, two industrial objectives were put into operation: Synthetic Rubber Plant II and Refinery II. The surface of the platform has exceeded 1000 hectares and includes the city platform based on the food industry, wood processing and others.
At the same time, beginning construction of the electrolytic caustic soda plant (H.C.M. 2068/1954), later became the Borzesti Chemical Plant, whose first capacities were put into operation in 1960, when the salt brought directly from the Târgu Ocna mine or the brine transported through the plants in pipelines began to be transformed into highly demanded products: caustic soda, chlorine, hydrogen.
Between June 18–25, 1962, a Soviet delegation led by Nikita Khrushchev took place in Romania. The Delegation, accompanied by Gheorghe Gheorghiu-Dej, visited the town of Onești and the industrial group. In the same year, between September 15–21, a government delegation of the German Democratic Republic, headed by Walter Ulbricht, visited Romania. It also visited the town of Onesti and the industrial complex. In September 1966 the Industrial Complex and the city were visited by Nicolae Ceaușescu and Ion Gheorghe Maurer.
Installations commissioned in 1960 were: diaphragm electrolysis, liquid chlorine evaporation-melting, lime chloride, sulfuric acid, monochlorobenzene, Detexan and hexachlorane - commissioning continued in 1961 with chlorination plants and methylene chloride. Featuring chlorine in large quantities, this plant becomes one of the largest chlorinated insecticides producers in the country, managing to cover not only the needs of agriculture, but also to provide products for export.
The operation of the third industrial unit on the current petrochemical complex was carried out in 1962, when the first quantities of Isopropylbenzene, phenol and acetone were produced. For industrial complex and for the national economy, this year was a crucial moment, since the commissioning of the Synthetic Rubber and Petrochemicals Complex has created the premises for a broad economic development for the coming years and a jump in the economic potential of Bacău County. These units continued with new technologies, at the oil refinery the atmospheric and vacuum distillation plants no. 3, thermal cracking, catalytic cracking no. 1 and 2, absorption-fractionation gas, coke calcination, catalytic reforming complex and furfurol gas oil solvent plant, which have created opportunities to capitalize products at a higher level. At the same pace, the electrolytic caustic soda plant increased production. At old plants have been added new ones: fatty alcohols, vinyl compounds, caustic soda. At the rubber plant, new polyisoprene rubber plants were put into operation.
On April 1, 1969, the three factories on the Borzești Industrial Complex merged into the giant "Petrochemical Industrial Group Borzeşti", and in 1973 it became the "Borzeşti Petrochemical Plant", comprising 12,000 of employees, out of which 463 have higher education. In the over 20 years that have passed since the establishment of the first plant, through an organic bonding between technological processes and through superior valorization, it has continuously strengthened its economic power, maintaining itself as the most important industrial unit of Bacău County.
In 1970 the chemical production of the Borzesti Petrochemical Industrial Group accounted for 99.9% of the production of the chemical industry of Bacău County and 8% of the chemical industry of the country.
At the end of 1979, the value of the fixed assets in the endowment amounted to 7860 million lei, resulting in an industrial production of almost 7 billion lei, representing 26% of the entire industrial production of the county. Value production in 1979 was 3.4 times higher than in 1965, when the average annual growth rate was 9.2%. Significant increases were recorded over 1965 in a series all products such as: caustic soda 1.9 times, synthetic rubber 4.7 times, phenol 2.4 times, polystyrene 3.7 times, gasoline 2.3 times, vinyl polychloride 1.4 times, insecticides 1.5 times.
The products manufactured by the petrochemical complex have been exported to more than 40 countries including: The union of Soviet Socialist Rebublics, China, Germany, Hungary, Yugoslavia, England, Italy, Spain, France Egypt, Israel, Czechoslovakia, Iran, Japan, Netherlands, Switzerland, Austria, Belgium, India, Poland, Bulgaria, Sweden, Turkey and others.
Between 11 and 14 October 1976, King Baudouin of Belgium, accompanied by Queen Fabiola, visited Romania, among others by visiting the petrochemical complex.The platform had 12,000 workers in 1980, achieving a productivity of 2.8 times higher than in 1965. The benefits obtained in 1979 by this unit amounted to 520 million lei.
The Petrochemical plant Borzeşti directly influenced the establishment and development of a new city, which became the municipality of Gheorghe Gheorghiu-Dej (Onești), which ensures conditions for the petrochemical workers of Trotuș Valley. The new city is remarkable by the pace of development and specialization, modern architecture and a dynamic influence area. These qualities were synthesized by the French geographer André Blanc - "Gheorghe Gheorghiu-Dej is the brightest example of the creative transformation of the natural environment based on systematic studies in order to raise the economic level of a region that was underdeveloped until short time ago."
Industrial structure
The Trotuș basin had a natural and human potential corresponding to economic and social transformations. After World War II, oversized industrial construction plans were developed that surpassed regional potential, leading to large investments, difficulties in raw materials supply and distribution of products and, in some cases, pollution of the area. In 1986, the workers of the Onești industry exceeded 22,000 people and the industrial platform reached 1,038 ha. In the first stage of development, the foundations of an energy industry were established.
After 1980 there were significant mutations in the structure of production, in the superior valorization of raw materials in the area. In 1984 over 54% of industrial production was petroleum products, 21,8% synthetic rubber and latex, 5,5% plastics, 4,8% insecticides, fungicides and herbicides for agriculture, 3,7% caustic soda and 9% organic and inorganic chemicals, solvents, chlorinates.
Energy industry
The Borzești Power Station began building in 1956, when the first 25 MW generator was installed. Until 1966 were completed with 25 MW, in 1957, 50 MW in 1960, 25 MW in 1961, 50 MW in 1962 and 1966. The largest increase in capacity was in 1969 with 2x200 MW, the main fuels being oil and the gas flowing from the Tazlău Valley. The installed power of the thermal plant in 1970 exceeded the installed power of existing generating sets throughout the country in 1938.
The grid generated electricity over the requirements of the industrial complex and the residential city, with production increasing 63.7 times in 1985 compared to 1956, so 110 kV, 220 kV and 400 kV power lines were built for the industrial centers in Moldavia and southeastern Transylvania and the railway networks in the Trotuș, Olt and Siret valleys.
Petrochemical industry
The No. 10 Oil Refinery is part of the large refinery category with capacity over 1 million tons. It consists of: Refinery I ("Onești 10") with electrical desalination plants (1957-1960), atmospheric distillation (1961) and Refinery II with gas fraction sections (1980), catalytic reforming (1980) hydrofinishing of gasoline (1980).
The refinery processes oil from Bacău County and some quantities are transferred from refineries in Muntenia or distributed from export. The transport of regional oil and petroleum products is done through pipelines or the railway network. Products include petrol, fuel oil, diesel fuel and derivatives such as benzene, xylene, orthoxylene, ethylbenzene, liquefied gases, and the like.
The Synthetic Rubber and Petrochemicals Complex produced the first quantities of synthetic ethylene-styrene butadiene rubber, being the only enterprise of its kind in the country. The construction took place between 1958 and 1963. Unlike the refinery which primarily processes petroleum into petroleum products (fractions), the rubber plant transforms oil fractions into finished products, such as polystyrene, phenol, acetone, benzene, used in the medicine and paint industry. Since 1976, a second polyisoprene rubber plant has been put into operation and later facilities for the manufacture of latex and butadiene-styrene rubbers.
The synthetic rubber output was 30,820 tonnes in 1965 and 155,909 tonnes in 1985, of which the polyisoprene rubber was 57,079 tonnes in 1985.
In 1970 the fourth line of rubber was put into operation and 70,000 tons of synthetic rubber was produced in that year. The manufactured rubber products were: CAROM 1500: for automotive tires, tractors, scooters, motorcycles, technical articles, conveyor belts, transmission belts and other items requiring good physical properties and good strength. CAROM 1502: for black and colored technical articles, sanitary ware, rubber cloth, carpets. CAROM 1503: for consumer goods, especially footwear. CAROM 1712: for cable and yarn insulation, technical articles, tires and many other applications.
Chemical industry
The Borzesti Chemical Plant is located in the southeastern part of the industrial platform. It was built between 1956 and 1964 with the following structure: caustic soda plant (1960), toxan plant (1961) and polyvinyl chloride - PVC (1964) plant with acetylene, monomer, polychlorinated vinyl emulsion, vinyl polychloride suspension. Acetylene was obtained from a mixture of methane and propane gas by the arc cracking process developed by Aurel Ionescu (1902-1954). The initial profile included chlorosodic products: caustic soda (sodium hydroxide), hydrochloric acid, aluminum chloride, lime chloride, further diversifying production, adding organic solvents: methyl chloride, methylene chloride, cloroform; plastics: vinyl polychloride, emulsion and suspension, ferric vinyl; fatty alcohols, liquid chlorine, and the like. In addition, installations for the production of ammonium chloride, chlorinated insecticides and others have been put into operation.
The chemical plant participated in the national production in the chemical branch by 14% - 25.6%. The production of caustic soda recorded an increase of 48.7 times in 1980 compared to 1960 and the production of insecticides by 30.6 times.
Machine building industry
Borzești Chemical Equipment Company was established between 1973 and 1976, in the following years, manufacturing products such as: technological equipment for chemical, petrochemical, crude, pulp and paper processing; metal structures and mounting elements. The raw materials used were purchased mainly from the Galați Steel Works, Roman Steel Pipes Works, "Republica" Bucharest Steel Pipes Works.
In 1980, I.U.C. Borzești was the only manufacturer of equipment for pilot plants in the chemical industry in the country. In the same year export activity started in countries such as: Soviet Union, Bulgaria, Austria and Germany.
References
Sources
Dr. Pintilie Rusu (coordinator); Stelian Nanianu, Nicolae Barabaș, Ioan Mirea, Dumitru Zaharia, Gheorghe Bucur, Vasile Florea (contributors); Județele Patriei – Județul Bacău, Ed. Sport-Turism, București (1980), pp. 158–160
Rozalia și Teodor Verde; Monografia Municipiului Onești – în date și evenimente , July 2003, pp. 44–47
Șandru Ioan, Toma V. Constantin, Aur Nicu; Orașele Trotușene – Studiu de geografie umană II, Întreprinderea Poligrafică Bacău (1989), pp. 190–197, 208
External links
Romanian Television (TVR) shooting, CAROM and No. 10 Oil Refinery, 1963
TVR shooting, inside the rubber plant CAROM, interview with sound, 1964
TVR shooting, No. 10 Oil Refinery, 1965
TVR shooting, Power Plant Borzești, 1973
TVR shooting, construction of L.E.A. Borzești-Iași, 1973
British Movietone archived shooting by AP Archive with the No. 10 Oil Refinery, 1956
Cineclub Cotidian Onești: "Întunecare" ("Darkness"), directed by Giliu Maximov, 1975 - cinematographic approach to the consequences of ingestion of methyl alcohol from the Borzești Chemical Plant
Cineclub Cotidian Onești: "Nuntă în cer" ("Wedding in the sky"), directed by Giliu Maximov, 1988 – the same topic with the short film "Darkness", after a real fact.
Documentary movie RAFO Onești, 2002
Documentary movie CAROM Onești, 2002
Reportage "România, te iubesc!", Prin cenușa imperiului petrochimic ("Through the ashes of the petrochemical empire"), 11–30 October 2015, part. 1, 2, 3 and part. I, II, III.
Energy infrastructure in Romania
Oil refineries in Romania
Rubber industry
Chemical plants
Companies of Bacău County | Borzești Petrochemical Plant | [
"Chemistry"
] | 4,230 | [
"Chemical process engineering",
"Chemical plants"
] |
59,633,745 | https://en.wikipedia.org/wiki/Biaoxingma%20method | The Biaoxingma Input Method (), also abbreviated to simply Biaoxingma (), is a kind of shape-based Chinese character input method invented by Chen Aiwen, an overseas Chinese scholar living in France in the 1980s. Because it is intuitive in the splitting of Chinese characters and has theoretical support in Chinese characters, it had once attracted widespread attention at the beginning of the invention and was listed as a key project in China Torch Project. However, there was afterwards no such influence as Wubi method and Zhengma method in terms of popularization and commercialization.
Biaoxingma was pre-installed by Microsoft in Chinese Windows 95 and Windows 98 first edition, but was removed from Windows 98 second edition and later Windows versions.
Biaoxingma was also installed in IBM AIX.
Basics
The smallest constituent parts of each Chinese character are called strokes. One or more strokes form the components of a character. Characters are divided into several components, which are coded to the English letter resembling them. Due to the resemblance of the letter and the character components it refer to, Biaoxingma is easy to learn and remember compared with Wubi method and Zhengma method. Moreover, the biggest advantage of Biaoxingma is that crossed strokes are never divided into two components. In other words, the character components never cross each other. This makes the way of splitting characters very intuitive.
Here are two examples:
"吼" - divided into - O+Z+L = OZL
"啊" - divided into - O+P+T+O = OPTO
References
CJK input methods
Input methods | Biaoxingma method | [
"Technology"
] | 325 | [
"Input methods",
"Natural language and computing"
] |
59,634,425 | https://en.wikipedia.org/wiki/Phenine%20nanotube | A phenine nanotube is a derivation or variant of short carbon nanotubes first reported in 2019.
They have a precise cylindrical structure with pores and a length index of 7, and have been made by a 9 step process starting with 1,3-dibromobenzene.
References
Carbon nanotubes | Phenine nanotube | [
"Materials_science"
] | 68 | [
"Nanotechnology",
"Materials science stubs",
"Nanotechnology stubs"
] |
59,638,244 | https://en.wikipedia.org/wiki/NGC%20759 | NGC 759 is an elliptical galaxy located 230 million light-years away in the constellation Andromeda. NGC 759 was discovered by astronomer by Heinrich d'Arrest on September 17, 1865. It is a member of Abell 262.
Despite being classified as a radio galaxy, the radio emission in NGC 759 could be due to star formation rather than an active galactic nucleus.
Dust disk
The central region of NGC 759 harbors a face-on dust disk with tightly wound spiral structure. The disk has a diameter of . The dust disk also contains a smaller circumnuclear molecular gas ring that has star formation in H II regions. These features may be the result of a merger of gas-rich disk galaxies or by the accretion of gas-rich material. In either scenario, the gas would have lost momentum and fallen to the center of the galaxy to produce the disk and current star formation. However, Vlasyuk et al. suggests that the disk and the smaller circumnuclear molecular gas ring with star formation inside the main disk formed from a tidal encounter between NGC 759 and a large spiral galaxy which was accompanied by a substantial gas accretion.
Molecular gas
NGC 759 contains 2.4 × 109 M☉ of molecular gas. Most of the gas is concentrated in a circumnuclear molecular gas ring with a diameter of . The gas may be the result of the same merger event that produced the circumnuclear molecular gas ring and the main disk.
SN 2002fb
NGC 759 has had one supernova, SN 2002fb which was discovered on September 6, 2002. It was classified as a type Ia supernova.
See also
List of NGC objects (1–1000)
References
External links
759
7397
Andromeda (constellation)
Astronomical objects discovered in 1865
Elliptical galaxies
Radio galaxies
Abell 262
1440 | NGC 759 | [
"Astronomy"
] | 386 | [
"Andromeda (constellation)",
"Constellations"
] |
67,543,042 | https://en.wikipedia.org/wiki/Charles%20G.%20Heyd | Charles Gordon Heyd (27 August 1884 – 4 February 1970) was an American surgeon and president of the American Medical Association in 1936–1937.
Biography
Heyd obtained a B.A. from the University of Toronto in 1905 and M.D. from University of Buffalo in 1909. During World War I he served as a Major in France. Heyd was an opponent of compulsory health insurance and socialized medicine. Instead, he favoured voluntary medical insurance and public health testing.
Heyd was Director of Surgery at New York Post-Graduate Medical School and Hospital and Professor of Clinical Surgery at Columbia University. He was President of the United Medical Service (1948–1951). In 1932, he received the Legion of Honour of France. He wrote the Preface for Lloyd Paul Stryker's Courts and Doctors, published in 1932.
He was President of the American Medical Association (1936–1937). In 1937, Heyd was awarded honorary degree of doctor of science by Temple University. In 1940, Heyd noted that most infections of the neck have their origin in the oral cavity.
Heyd died on 4 February 1970.
Opposition to water fluoridation
Heyd was an opponent of water fluoridation. He has been quoted as saying "I am appalled at the prospect of using water as a vehicle for drugs. Fluoride is a corrosive poison which will produce harm on a long-term basis".
Heyd's comment has been widely cited in anti-fluoridation literature as an argument from authority because he was a former President of the AMA. However, Heyd was President of the AMA for two years in the 1930s long before evidence of the effectiveness from fluoridation was available to examine. Since Heyd, no other AMA President has opposed fluoridation.
Selected publications
Liver and Its Relation to Chronic Abdominal Infection (1924)
The Doctor in Court (1941)
References
1884 births
1970 deaths
American surgeons
Columbia Medical School faculty
Canadian emigrants to the United States
Writers from Brantford
Presidents of the American Medical Association
American recipients of the Legion of Honour
University at Buffalo alumni
University of Toronto alumni
Water fluoridation | Charles G. Heyd | [
"Chemistry"
] | 427 | [
"Water treatment",
"Water fluoridation"
] |
67,543,339 | https://en.wikipedia.org/wiki/Hypsizygus%20ulmarius | Hypsizygus ulmarius, also known as the elm oyster mushroom, and less commonly as the elm leech, elm Pleurotus, is an edible fungus. It has often been confused with oyster mushrooms in the Pleurotus genus but can be differentiated easily as the gills are either not decurrent or not deeply decurrent. While not quite as common as true oyster mushrooms, they have a wide range globally in temperate forests. The mushrooms and vegetative hyphae of this species have been studied in recent years for their potential benefits to human health, and mycoremediation.
Taxonomy and phylogeny
The taxonomic name of H. ulmarius means both “high up” (Hypsi-) and “yoke” (-zygus), referring to where the mushroom can be found attached to its host tree. The species name refers to elm (Ulmus spp.), a tree the fungus commonly grows on. This species was first described in 1791 as Agaricus ulmarius by Jean Baptiste Francois Pierre Bulliard, a French physician and botanist responsible for the first description of many species of fungi. At this time, most gilled mushrooms were placed in this genus. With the creation of the genus Pleurotus by Paul Kummer for oyster mushrooms, this species was then named Pleurotus ulmarius. This was most likely due to the similar appearance of the fruiting body of these species. When famed French mycologist Robert Kühner revised fungi in the family Agaricales into more genera, the elm oyster mushroom was coined Lyophyllum ulmarium. However, this species was most recently moved to its current genus as Hypsizygus ulmarius in 1984 by Canadian mycologist Scott Redhead. This move was based on ecological and morphological similarity to another species in Hypsizygus.
This final shift from Lyophyllum to Hypsizygus was supported by a later study comparing DNA for the large ribosomal subunit RNA coding region divergent domain (D2) of species in the genus Lyophyllum. Based on both culture morphologies and the phylogeny produced using the DNA, the authors agreed with Redhead's classification. Further DNA evidence suggests that the genus Hypsizygus is polyphyletic, however, meaning that these species lack a common ancestor in the current phylogeny. There is still much to learn about the phylogenetic relationship of the (currently three) species in the Hypsizygus genus.
Some texts also confuse this species with H. tessellatus due to their similar habitats and appearances.
Morphology
The mushrooms of this species appear white to cream, and are relatively uniform in color throughout. The stipe extends perpendicular from the fungus's host tree and then bends vertically to form the cap. The stipe is bare of any rings or other features. Additionally, the stipe connects almost perfectly in the center of the cap. The cap itself is usually about in diameter, though it may be larger, and is convex with an incurved margin. Larger caps can appear to be depressed. They will be uniform and smooth, though they can become aerolate as they age. The gills are "adnate or only very slightly decurrent" in contrast with the gills of the commonly confused Pleurotus spp., which are deeply decurrent. The mushrooms of H. ulmarius are often found in clusters of 1 to 3, though there may be more on larger tree wounds.
Cultures of this species are known to produce both sexual and asexual spores. The asexual arthrospores may be mono- or multinucleate. There is conflicting data on the size of the sexual basidiospores of H. ulmarius, but the original description of the species by Redhead reports that they are usually about 5–7 micrometers in diameter. Their shape is subglobose to ellipsoidal. The spore print of this species is white to pale cream.
Ecology
The H. ulmarius mushroom commonly grows on tree species like elm, box elder (Acer negundo), and beech, though it may be found on other trees as well. Elm oyster mushrooms are known to grow high up in the wounds or scars of the host tree. They are found in temperate forests across North America, Europe and Asia. Despite how widespread they are, the mushrooms are relatively rare compared to their Pleurotus spp. lookalikes.
H. ulmarius is considered both a saprotroph and parasite as it is not clear whether it feeds on live or dead tissue of its hosts, though it is found on live trees. This species causes brown rot on damaged areas of its host species. Interestingly, however, this species also has a moderate ability to dissolve lignin, too, like a white rot fungus. The fungus accomplishes this by using a complex suite of enzymes that dissolve both cellulose and lignin like laccase. It is not unheard of for brown-rot fungi to produce laccase, an enzyme primarily involved in the lignin degradation process, but the fungus's use of the enzyme is rather uncommon. This production of a brown rot also helps differentiate the fungus from Pleurotus spp., which are mainly white rot fungi.
This species is also easily culturable on a variety of media types. It can also be grown in similar substrates as true oyster mushrooms: paper, straw, logs, etc.
Human uses
Culinary
Although many foragers feel that H. ulmarius mushrooms are tougher and do not taste as good as oyster mushrooms in the Pleurotus genus, they are still sought after in the wild. There are even commercially available kits to grow these mushrooms at home. Like most edible mushrooms, they are good sources of protein, fiber, and Vitamin B.
Human health
There is both historical and modern interest in H. ulmarius’s possible medicinal applications, and most of these recent studies have been primarily performed in India. Studies have found compounds in both the mycelium and the fruiting body believed to be anti-inflammatory, antioxidant, antitumor and antidiabetic. It is considered a medicinal fungus in China.
Mycoremediation
Mycoremediation refers to the breakdown and removal of toxins from the environment using fungi. H. ulmarius has the demonstrated potential to accomplish this in a couple different ways. For example, the fungus uses the enzyme laccase to help decompose the lignin in the tissue of its host tree. Because this enzyme has low substrate specificity, it may be used to biodegrade materials like plastics. Scientists are researching what affects laccase production in order to take advantage of this enzyme’s many uses. Additionally, laccase produced by H. ulmarius has also been shown to degrade different dyes, which could prove useful in treating water.
References
Lyophyllaceae
Edible fungi
Fungi described in 1791
Fungi of Asia
Fungi of Europe
Fungi of North America
Taxa named by Jean Baptiste François Pierre Bulliard
Fungus species | Hypsizygus ulmarius | [
"Biology"
] | 1,462 | [
"Fungi",
"Fungus species"
] |
67,543,732 | https://en.wikipedia.org/wiki/Francisco%20Ernesto%20Baralle | Francisco Ernesto (Tito) Baralle (born 26 October 1943, in Buenos Aires) is an Argentinian geneticist best known for his innovations in molecular biology and in particular the discovery of how genes are processed and mechanisms in mRNA splicing.
Biography
Francisco Ernesto (a.k.a. Tito) Baralle was born in Buenos Aires, Argentina on 26 October 1943. After completing his Ph.D. studies at the Department of Organic Chemistry, he transferred to the Instituto de Investigaciones Bioquimicas Fundacion Campomar directed by Prof. Luis F. Leloir, now the Leloir Institute. In 1974, he moved to the MRC Laboratory of Molecular Biology, Cambridge University, UK, where he worked in the Division directed by Dr. Frederick Sanger. From (1980 to 1990), he was University Lecturer of Pathology at Oxford University and Fellow of Magdalen College. In 1993, he was awarded the Platinum Konex Award for Science and Technology (Argentina) as the best scientist of the decade in Genetics and Cytology.
In September 1990, he was appointed Director of the Trieste Component of International Centre for Genetic Engineering and Biotechnology (ICGEB) an autonomous, intergovernmental organisation originally established under UNIDO. From 2004-2014 he was the Director-General of the institute, overseeing laboratories in 4 continents, spanning 63 countries championing collaboration, scientific education and dissemination of Science and Biotechnology worldwide.
During his 10 year tenure as Director-General, and as well as expanding his medical and scientific research, he was responsible for the establishment of a Biotechnology Development Group serving as a training hub for researchers of developing countries, transferring biopharmaceutical know-how locally.
He was a strong supporter of the internationalization of science and took the 2-component (Italy and India) International Centre for Genetic Engineering and Biotechnology, and expanded it to 4 component institutions, establishing, and opening new centres in Africa and Argentina, giving opportunities and access to young scientists from the developing world.
Scientific activity
In 1977, and as a staff scientist at the laboratory of molecular biology, Cambridge, Tito published the sequence of the messenger RNA coding for beta-globin, the first complete primary structure of a eukaryotic mRNA. In 1979, his research group isolated the gene for epsilon-globin (HBE1), a component of human embryonic hemoglobin. He was one of the first to describe the pre-mRNA alternative splicing process in the 1980s.
His studies on how genes are processed described the first sequences within exons that control splicing, exonic splicing enhancer (ESE) and has since made critical contributions to understanding the molecular mechanisms involved in this important cellular process in health and disease. He first identified the protein called TDP 43, that is now known to play a central role in certain neurodegenerative disorders (Frontotemporal lobar degeneration, Amyotrophic lateral sclerosis and Alzheimer disease). Tito Baralle is a leader and innovator in molecular biology and in particular the discovery of how genes are processed and mechanisms in mRNA splicing.
Honors and awards
2014 Doctor Honoris Causae of the Faculty of Medicine Universidad de la Republica, Montevideo, Uruguay
2010 University of Nova Gorica, Slovenia Golden Plate Award for his work on international scientific collaboration. Full Professor of Molecular Biology
2010 Premio Raices, granted very selectively by the Minister of Science and Technology of Argentina for promotion of scientific education in Argentina
2010 Fellow of the Academy of Sciences for the Developing World-TWAS for the advancement of science in the developing world
2001 Fellow National Academy of Sciences of Argentina
1999 Visiting Professor University of Trieste
1993 Premio Konex de Platino, Konex Foundation Platinum prize in Science and technology, awarded to best scientist of the decade in Genetic and Cytology.
1993 Konex Foundation Merit Diploma in Science and Technology
1993 Honorary Professor of Biochemistry at the Faculty of Sciences, University of Buenos Aires
1980 Member of the European Molecular Biology Organization (EMBO)
Scientific publications
Tito has over 200 scientific publications, some of his most cited are:
"The Structure and evolution of the human b-globin gene family"
“TDP-43 Mutations in Familial and Sporadic Amyotrophic Lateral Sclerosis”
"Primary structure of human fibronectin: Differential splicing may generate at least 10 polypeptides from a single gene"
“Genomic variants in exons and introns: identifying the splicing spoilers”
“Characterisation and functional implications of the RNA binding properties of nuclear factor TDP-43, a novel splicing regulator of CFTR Exon 9”
References
Living people
1943 births
21st-century Argentine biologists
Geneticists
Molecular biologists
Fellows of Magdalen College, Oxford | Francisco Ernesto Baralle | [
"Chemistry"
] | 983 | [
"Biochemists",
"Molecular biology",
"Molecular biologists"
] |
67,544,843 | https://en.wikipedia.org/wiki/Index%20of%20American%20Design | The Index of American Design program of the Federal Art Project produced a pictorial survey of the crafts and decorative arts of the United States from the early colonial period to 1900. Artists working for the Index produced a collection of 18,257 watercolor drawings of American decorative and folk arts objects, held by the National Gallery of Art in Washington, D.C. Although the collection was created by about 400 artists between 1935 and 1942, it was seen more as documentation than personal expression, which is among the reasons it is lesser known than other Federal Art Projects. The Index's goal was establishing the basis for and contextualizing American art and design using, as a basis, these items created between the colonial period and the end of the nineteenth century.
Constance Rourke was the editor and resident scholar of the Index; Ruth Reeves was its field supervisor. Rourke's interest stemmed, in part, from her work on Charles Sheeler. Among the projects that grew out of the Index is Clarence Hornung's Treasury of American Design and as a jobs creation vehicle, the creation of the index employed about one thousand individuals in thirty four different states.
References
External links
National Gallery of Art
American art movements
Federal Art Project | Index of American Design | [
"Engineering"
] | 242 | [
"Design stubs",
"Design"
] |
67,545,702 | https://en.wikipedia.org/wiki/Exometeorology | Exometeorology is the study of atmospheric conditions of exoplanets and other non-stellar celestial bodies outside the Solar System, such as brown dwarfs. The diversity of possible sizes, compositions, and temperatures for exoplanets (and brown dwarfs) leads to a similar diversity of theorized atmospheric conditions. However, exoplanet detection technology has only recently developed enough to allow direct observation of exoplanet atmospheres, so there is currently very little observational data about meteorological variations in those atmospheres.
Observational and theoretical foundations
Modeling and theoretical foundations
Climate models have been used to study Earth's climate since the 1960s and other planets in our solar system since the 1990s. Once exoplanets were discovered, those same models were used to investigate the climates of planets such as Proxima Centauri b and the now-refuted Gliese 581g. These studies simulated what atmospheric pressures and compositions are necessary to maintain liquid water on each terrestrial exoplanet's surface, given their orbital distances and rotation periods. Climate models have also been used to study the possible atmospheres of the Hot Jupiter HD 209458b, the Hot Neptune GJ 1214b, and Kepler-1649b, a theorized Venus analog.
These models assume that the exoplanet in question has an atmosphere in order to determine its climate. Without an atmosphere, the only temperature variations on the planet's surface would be due to insolation from its star. Additionally, the main causes of weather - air pressure and air temperature differences which drive winds and the motion of air masses - can only exist in an environment with a significant atmosphere, as opposed to a tenuous and, consequently, rather static atmosphere, like that of Mercury. Thus, the existence of exometeorological weather (as opposed to space weather) on an exoplanet depends on whether it has an atmosphere at all.
Recent discoveries and observational foundations
The first exoplanet atmosphere ever observed was that of HD 209458b, a Hot Jupiter orbiting a G-type star similar in size and mass to our sun. Its atmosphere was discovered by spectroscopy; as the planet transited its star, its atmosphere absorbed some of the star's light according to the detectable absorption spectrum of sodium in the planet's atmosphere. While the presence of sodium was later refuted, that discovery paved the way for many other exoplanet atmospheres to be observed and measured. Recently, terrestrial exoplanets have had their atmospheres observed; in 2017, astronomers using a telescope at the European Southern Observatory (ESO) in Chile found an atmosphere on earth-sized exoplanet Gliese 1132 b.
However, measuring traditional meteorological variations in an exoplanet's atmosphere — such as precipitation or cloud coverage — is more difficult than observing just the atmosphere, due to the limited resolutions of current telescopes. That said, some exoplanets have shown atmospheric variations when observed at different times and other evidence of active weather. For example, an international team of astronomers in 2012 observed variations in hydrogen escape speeds from the atmosphere of HD 189733 b using the Hubble Space Telescope. Additionally, HD 189733 b and Tau Boötis Ab have their hottest surface temperatures displaced eastward from their subsolar points, which is only possible if those tidally-locked planets have strong winds displacing the heated air eastward, i.e. a westerly wind. Lastly, computer simulations of HD 80606b predict that the sudden increase in insolation it receives at periastron spawns shockwave-like windstorms that reverberate around the planet and distribute the sudden heat influx.
Theorized weather
Empirical observations of weather on exoplanets are still rudimentary, due to the limited resolutions of current telescopes. What little atmospheric variations can be observed usually relate to wind, such as variations in the escape speeds of atmospheric hydrogen in HD 189733b or just the speeds of globally circulating winds on that same planet. However, a number of other observable, non-meteorological properties of exoplanets factor into what exoweather is theorized to occur on their surfaces; some of these properties are listed below.
Presence of an atmosphere
As mentioned previously, exometeorology requires that an exoplanet has an atmosphere. Some exoplanets that do not currently have atmospheres began with one; however, these likely lost their primordial atmospheres due to atmospheric escape from stellar insolation and stellar flares or lost them due to giant impacts stripping the exoplanet's atmosphere.
Some exoplanets, specifically lava planets, might have partial atmospheres with unique meteorological patterns. Tidally-locked lava worlds receive so much stellar insolation that some molten crust vaporizes and forms an atmosphere on the day side of the planet. Strong winds attempt to carry this new atmosphere to the night side of the planet; however, the vaporized atmosphere cools as it nears the planet's night side and precipitates back down to the surface, essentially collapsing once it reaches the terminator. This effect has been modeled based on data from transits of K2-141b as well as CoRoT-7b, Kepler-10b, and 55 Cancri e. This unusual pattern of crustal evaporation, kilometer-per-second winds, and atmospheric collapse through precipitation might be provable with observations by advanced telescopes like Webb.
Exoplanets with full atmospheres are able to have diverse ranges of weather conditions, similar to weather on the terrestrial planets and gas giants of our Solar System. Planet-wide atmospheres allow for global air circulation, stellar thermal energy distribution, and relatively fast chemical cycling, as seen in the crustal material transportation by lava worlds' partial atmospheres and Earth's own water and carbon cycles. This ability to cycle and globally distribute matter and energy can drive iron rain on hot Jupiters, super-rotating winds on HD 189733b, and atmospheric precipitation and collapse on tidally-locked worlds.
Orbital properties
One of the most important factors determining an exoplanet's properties is its orbital period, or its average distance from its star. This alone determines a planet's effective temperature (the baseline temperature without added insulation from an atmosphere) and how likely the planet is to be tidally locked. These, in turn, can affect what chemical compositions of clouds can be present in a planet's atmosphere, the general motion of heat transfer and atmospheric circulation, and the locations where weather can occur (as with tidally-locked lava worlds with partial atmospheres).
For example, a gas giant's orbital period can determine whether its wind patterns are primarily advective (heat and air flowing from the top of the star-heated atmosphere to the bottom) or convective (heat and air flowing from down near the gradually contracting planet's core up through the atmosphere). If a gas giant's atmosphere receives more heat from insolation than the planet's unending gravitational contraction, then it will have advective circulation patterns; if the opposite heat source is stronger, it will have convective circulation patterns, as Jupiter exhibits.
Additionally, an exoplanet's average incident stellar radiation, determined by its orbital period, can determine what types of chemical cycling an exoplanet might have. Earth's water cycle occurs because our planet's average temperature is close enough to water's triple point (at normal atmospheric pressures) that the planet's surface can sustain three phases of the chemical; similar cycling is theorized for Titan, as its surface temperature and pressure is close to methane's triple point.
Similarly, an exoplanet's orbital eccentricity – how elliptical the planet's orbit is – can affect the incident stellar radiation it receives at different points in its orbit, and thus, can affect its meteorology. An extreme example of this is HD 80606b's shockwave-like storms that occur whenever the planet reaches the innermost point in its extremely eccentric orbit. The difference in distance between its apastron (analogous to Earth's aphelion) and its periastron (perihelion) is so large that the planet's effective temperature varies greatly throughout its orbit. A less extreme example is eccentricity in a terrestrial exoplanet's orbit. If the rocky planet orbits a dim red dwarf star, slight eccentricities can lead to effective temperature variations large enough to collapse the planet's atmosphere, given the right atmospheric compositions, temperatures, and pressures.
See also
Atmosphere and extraterrestrial atmosphere
Atmospheric circulation of exoplanets; the mathematical models governing exoplanetary air circulation
Atmospheric physics
References
Branches of meteorology
Atmosphere
Planetary science
Exoplanetology
Exoplanets
Astronomy | Exometeorology | [
"Astronomy"
] | 1,813 | [
"Planetary science",
"nan",
"Astronomical sub-disciplines"
] |
67,546,035 | https://en.wikipedia.org/wiki/Ramalic%20acid | Ramalic acid is an organic compound of the depside class with the molecular formula C18H18O7. Ramalic acid occurs as a secondary metabolite in some lichens like Ramalina pollinaria wherfrom ramalic acid has its name. Ramalic acid can be used as a dye.
References
Further reading
Polyphenols | Ramalic acid | [
"Chemistry"
] | 75 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
67,548,335 | https://en.wikipedia.org/wiki/Town%20Planning%20Associates | Town Planning Associates was a design firm in New York City, active between 1942 and 1959, which included Paul Lester Wiener, Paul Schulz, Josep Lluis Sert. The firm produced urban design and city planning in various new or existing South American cities including Bogotá, Chimbote in Peru, and Havana. Sert's master plan for Havana, Havana Plan Piloto, was notable for its integration of natural landscape into new urban and existing building schemes. Town Planning Associates made prominent use of patios and other aspects of Mediterranean architecture adapted to South and Central America. They employed modernist principles of the Congrès Internationaux d'Architecture Moderne (CIAM) and the Athens Charter. The charter got its name from the location of the fourth CIAM conference in 1933, which, due to the deteriorating political situation in Russia, took place on the SS Patris II bound for Athens from Marseilles. This conference was documented in a film commissioned by Sigfried Giedion and made by his friend László Moholy-Nagy "Architects' Congress." The Charter had a significant impact on urban planning after World War II and, through Josep Lluis Sert and Paul Lester Wiener, especially on the proposed modernization of Havana.
History
Wiener joined José Luis Sert in 1942 to form Town Planning Associates which operated until 1959, when they finished the Havana Plan Piloto, as an architectural, urban planning, and site planning consultant firm. During this period, Wiener and Sert lectured in the United States and Latin America as experts in urban planning.
Their designs exhibited elements of the "functional city" doctrine that Town Planning Associates promoted the Congrès Internationaux d'Architecture Moderne (CIAM), an organization founded by modern movement architects in 1928. The doctrine was codified in a document called the Athens Charter, drafted at CIAM's fourth meeting in 1933 in Greece.
It also promoted ideas of GATEPAC (Grupo de Artistas y Técnicos Españoles Para la Arquitectura Contemporánea) the Spanish branch of C.I.A.M.
Writing in reference to the writings of Josep Lluís Sert, Joan Ockman notes:
Gallery
See also
Havana Plan Piloto
Josep Lluís Sert
Paul Lester Wiener
Mario Romañach
Jean-Claude Nicolas Forestierl
Congrès Internationaux d'Architecture Moderne
GATEPAC
References
External links
Architects' Congress (Trailer)
Town Planning Associates Directias Generles_Miami Libraries Digital Collections
Paul Lester Wiener papers, 1913-1968
«La arquitectura contemporánea en España», Cahiers d'Art, 1931, n.º 3, págs. 157-164 (in Spanish)
«Gatepac y movimiento moderno». In Artehistoria.
«A.C. La revista del GATEPAC (1931-1937) en el Museo Reina Sofía», Revista de Arte Logopress
Museo Nacional Centro de Arte Reina Sofía, «A.C. La revista del GATEPAC». Pamphlet from an exhibition 29 October 2008 – 5 January 2009
Plan Piloto de La Havana
Neoclassical architecture in Cuba
Land use
Legal codes
Urban planning by country
Architecture groups
Modernist architecture
Modernist architects
Urban planning organizations
Architectural theory
Arts organizations established in 1942
Organizations disestablished in 1942 | Town Planning Associates | [
"Engineering"
] | 675 | [
"Architectural theory",
"Architecture"
] |
67,548,840 | https://en.wikipedia.org/wiki/Obata%20Kitayama%20Haniwa%20Production%20Site | The is an archaeological site with the ruins of a large-scale Kofun period factory for the production of haniwa clay funerary pottery, located in what is now the town of Ibaraki in Ibaraki Prefecture in the northern Kantō region of Japan. It received protection as a National Historic Site in 1992.
Overview
The Obata Kitayama site is located on a plateau at an elevation of 22.5 to 27 meters, on the southern bank of the Hinuma River and is Japan's largest known haniwa production site. A large amount of haniwa were discovered when the land was cleared by farmers expanding their fields in 1958. In 1987 a new kiln site was discovered from a western side valley, so the remains were found over a much wider area than originally expected. Further archaeological excavations from 1987 to 1988 found that the area covered approximately eight hectares and included two clay mines, eight production locations, and 59 kilns. The haniwa recovered from this location were in a wide variety of styles, including cylindrical, "morning glory-shaped", shield-shaped, horse-shaped, as well as anthropomorphic in the form of a warrior, a figure blowing a whistle, a figure holding a vase, and other configurations. Haniwa made at this site have been recovered from a wide area around Ibaraki Prefecture, including the Funazukayama Kofun on the north coast of Lake Kasumigaura, 15 kilometers away.
The area has an effective natural environment for ceramics production, with high quality clay and abundant spring water and wood for fuel. The site is believed to have been in operation from the latter half of the 6th century to the 7th century AD.
The site is located a short distance from the "Akasaka Iriguchi" bus stop on the Kanto Railway Bus from Mito Station.
See also
List of Historic Sites of Japan (Ibaraki)
References
External links
Ibaraki Tourist Information
Ibaraki town tourism site
Ibaraki Prefectural Board of Education
Ibaraki town official site
Kofun period
History of Ibaraki Prefecture
Ibaraki, Ibaraki
Historic Sites of Japan
Hitachi Province
Japanese pottery kiln sites | Obata Kitayama Haniwa Production Site | [
"Chemistry",
"Engineering"
] | 452 | [
"Kilns",
"Japanese pottery kiln sites"
] |
67,548,881 | https://en.wikipedia.org/wiki/Kawaratsuka%20Kiln | The is an archaeological site with the ruins of a Nara to Heian period factory for the production of earthenware, located in what is now the city of Ishioka in Ibaraki Prefecture in the northern Kantō region of Japan. It received protection as a National Historic Site in 2017.
Overview
roof tiles made of fired clay were introduced to Japan from Baekche during the 6th century along with Buddhism. During the 570s under the reign of Emperor Bidatsu, the king of Baekche sent six people to Japan skilled in various aspects of Buddhism, including a temple architect. Initially, tiled roofs were a sign of great wealth and prestige, and used for temple and government buildings. The material had the advantages of great strength and durability, and could also be made at locations around the country wherever clay was available.
The Kawarazuka kiln ruins were discovered during the clearing of an adjacent forest in 1968. An archaeological excavation found a total of 35 kilns across an area 130 meters north-to-south and 80 meters east-to-west. These kilns were made by hollowing out a clay hill to form an anagama-style staged kiln. Subsequent investigations found that one kiln was used for the production of Sue ware, whereas 34 kilns were specialized for roof tile production. An iron making furnace was also found in the area. From pottery shards found at site, it is likely that the kilns were the official kilns of Hitachi province and that tiles manufactured at the site were used in the construction of the provincial capital, Hitachi Kokubun-ji, Hitachi Kokubun-niji and the Baraki temple ruins, all of which date from around the Tenpyō era, or approximately 741 AD. The kilns remained in use through the first half of the 10th century.
The site was designated a Prefectural Historic Site in 1937 and was raised to national status in 2017.
See also
List of Historic Sites of Japan (Ibaraki)
References
External links
Prefectural Board of Education
Ishioka City official site
Ishioka Tourist Information site
History of Ibaraki Prefecture
Ishioka, Ibaraki
Historic Sites of Japan
Hitachi Province
Japanese pottery kiln sites | Kawaratsuka Kiln | [
"Chemistry",
"Engineering"
] | 462 | [
"Kilns",
"Japanese pottery kiln sites"
] |
67,549,085 | https://en.wikipedia.org/wiki/NGC%203945 | NGC 3945 is a barred lenticular galaxy in the constellation Ursa Major. It was discovered on March 19, 1790, by the astronomer William Herschel.
NGC 3945 has a complex structure, with two concentric bars and a pseudobulge. Unlike classical bulges which are like miniature elliptical galaxies, pseudobulges have features similar to disk galaxies, including a flattened structure and significant rotation. It is classified as a LINER galaxy. The formation history of NGC 3945 is likely quite complex, with the pseudo-bulge being formed gradually from disk material, while bulges (spheroidal components) would have formed from violent merger events.
Unlike galaxies with similar velocity dispersions and luminosities, the central black hole of NGC 3945 has an unusually low mass, estimated to be around . However, it is also possible that NGC 3945 has no central black hole at all.
References
External links
Ursa Major
3945
Barred lenticular galaxies
LINER galaxies
037258 | NGC 3945 | [
"Astronomy"
] | 202 | [
"Ursa Major",
"Constellations"
] |
67,550,294 | https://en.wikipedia.org/wiki/Mischococcus | Mischococcus is a genus of algae belonging to the family Mischococcaceae.
The species of this genus are found in Europe.
Species:
Mischococcus confervicola Nägeli
References
Xanthophyceae
Ochrophyte genera | Mischococcus | [
"Biology"
] | 55 | [
"Algae stubs",
"Algae"
] |
67,550,330 | https://en.wikipedia.org/wiki/Montanelia | Montanelia is a genus of lichenized fungi belonging to the family Parmeliaceae. It was circumscribed by Pradeep K. Divakar, Ana Crespo, Mats Wedin, and Theodore L. Esslinger in 2012 to accommodate a group of five species previously assigned to the genus Melanelia.
The genus has almost cosmopolitan distribution.
Species:
Montanelia disjuncta
Montanelia occultipanniformis
Montanelia panniformis
Montanelia predisjuncta
Montanelia saximontana
Montanelia secwepemc
Montanelia sorediata
Montanelia tominii
References
Sources
Lichen genera
Parmeliaceae
Fungi
Taxa named by Pradeep Kumar Divakar | Montanelia | [
"Biology"
] | 145 | [
"Fungi"
] |
67,550,535 | https://en.wikipedia.org/wiki/Copper%28II%29%20lactate | Copper(II) lactate, also referred to as cupric lactate, is the chemical compound with the formula Cu(C3H5O3)2. It is a green powder that readily dissolves in hot water to form a green solution, often more blue than the acetate. This complex has been used to modify the solubility of copper(II) in alkaline media, which allows controlled electrodeposition of cuprous oxide.
Bibliography
Copper(II) compounds
Lactates | Copper(II) lactate | [
"Chemistry"
] | 103 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
67,550,887 | https://en.wikipedia.org/wiki/Plant%20Protection%20and%20Inspection%20Services%20%28Israel%29 | The Plant Protection and Inspection Services unit is an agency of the Ministry of Agriculture of Israel. PPIS handles phytosanitary matters both within Israel and in foreign trade. In pursuit of that purpose, it operates offices both within the country and in its foreign embassies, and acts as representative to some international bodies such as the IPPC (International Plant Protection Convention) and the EPPO (European and Mediterranean Plant Protection Organization).
External links
References
Agriculture in Israel
Phytosanitary authorities
Export and import control
Regulators of biotechnology products
Foreign trade of Israel | Plant Protection and Inspection Services (Israel) | [
"Biology"
] | 114 | [
"Biotechnology products",
"Regulators of biotechnology products",
"Regulation of biotechnologies"
] |
67,551,811 | https://en.wikipedia.org/wiki/NGC%20731 | NGC 731 is an elliptical galaxy located in the constellation of Cetus about 172 million light-years away from the Milky Way. It was discovered by William Herschel on January 10, 1785. It has a luminosity of .
References
External links
Cetus
731
Elliptical galaxies
007118 | NGC 731 | [
"Astronomy"
] | 62 | [
"Cetus",
"Constellations"
] |
67,551,966 | https://en.wikipedia.org/wiki/Qatar-4 | Qatar-4 is a faint K-dwarf star that hosts a planet in the constellation Andromeda. With an apparent magnitude of 13.60, it is impossible to detect with the naked eye, but can be detected with a powerful telescope. Qatar-4 is currently located 1,083 light years away based on parallax.
Properties
This star is a relatively young star with an age of only 170 million years. At this age, it is still on the main sequence. Qatar-4 has 89.6% the mass of the Sun, and 84.9% the latter's radius. Despite all of this, it only has 48.1% of the Sun's luminosity, which corresponds to an effective temperature of . Qatar-4 has a similar metallicity to the Sun, and rotates at a rate of .
Planetary system
In 2016, the Qatar Exoplanet Survey discovered a planet around this star.
Qatar-4b
Qatar-4b is a Super-Jupiter orbiting the star Qatar-4 every 1.8 days. It was discovered in 2016 by the Qatar Exoplanet Survey (QES).
This planet has a very short orbit, with only 1.8 days for it to complete an orbit around Qatar-4. The period corresponds with a separation of around , which is almost 20 times closer than Mercury is to the Sun. Despite that, it has a perfectly round orbit. Since the host is an active star, Qatar-4 may be destroyed by tidal waves from the star.
Qatar-4b has over 5 times the mass of Jupiter. Despite this, it has a radius that is only 13.5% larger than the latter's. This planet has an effective temperature of 1,385 K, which classifies as a hot Jupiter, and is denser than Jupiter, with about 4 times the density.
See also
Qatar-1
Qatar-2
Qatar-3
Qatar-5
References
Andromeda (constellation)
K-type main-sequence stars
Planetary transit variables
Planetary systems with one confirmed planet | Qatar-4 | [
"Astronomy"
] | 418 | [
"Andromeda (constellation)",
"Constellations"
] |
67,552,202 | https://en.wikipedia.org/wiki/List%20of%20Boutique%20Air%20destinations | Boutique Air serves the following destinations:
Former destinations
References
Travel
Airlines based in California
Regional airlines of the United States | List of Boutique Air destinations | [
"Physics"
] | 23 | [
"Physical systems",
"Transport",
"Travel"
] |
67,552,812 | https://en.wikipedia.org/wiki/Time%20in%20Austria | In Austria, the standard time is Central European Time (CET; UTC+01:00). Daylight saving time is observed from the last Sunday in March (02:00 CET) to the last Sunday in October (03:00 CEST).
History
The Austro-Hungarian Empire adopted CET on 1 October 1891. At first railways and post offices, cities such as Prague and Budapest, however not Vienna. Vienna eventually adopted CET on 1 April 1893.
Time notation
IANA time zone database
In the IANA time zone database, Austria is given the zone Europe/Vienna.
See also
Time in Europe
List of time zones by country
List of time zones by UTC offset
References
Notes
External links
Current time in Austria at Time.is | Time in Austria | [
"Physics"
] | 151 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
71,915,843 | https://en.wikipedia.org/wiki/Godzilla%20%28star%29 | Godzilla is a variable star in the Sunburst galaxy at redshift z = 2.37 (or 10.9 billion light years from Earth), observed through the gravitational lens PSZ1 G311.65-18.48.
It was originally identified in the NW arc as a possible transient event in images taken with the Hubble Space Telescope (HST).
As of October 2022, it is the most luminous star that can be currently observed. This is possible because the star is believed to be undergoing an episode of temporary increased luminosity that has lasted at least seven years, combined with an estimated magnification of at least a factor of 2000.
Some spectral features in Godzilla resemble those of other variable stars in the Milky Way Galaxy such as Eta Carinae, suggesting that Godzilla could be close to the end of its life. Godzilla is believed to be going through an episode similar to the Great Eruption of Eta Carinae in the 19th century, during which the star was likely among the brightest in the universe at about .
The extreme magnification of Godzilla is partially due to a nearby substructure, probably a dwarf galaxy, not seen in the HST images (but recently detected in new JWST images), that is also close to the critical curve of the cluster. This unobserved substructure is believed to be dominated by dark matter.
Godzilla is named after the Kaiju and makes reference to its monstrous nature. Other stars named after Kaiju include Mothra, which shares many of the characteristics of Godzilla.
A recent work showed that Godzilla's source-frame ultraviolet light and nebular emission lines as measured by MUSE and X-shooter at the Very Large Telescope (VLT) can be quantitatively explained as that of a star cluster 4-6 Myr after formation and weighing millions of solar masses, magnified by a factor between about 500 and 2000. The authors show that the ionized gas as the source of Godzilla's nebular emission is enriched with nitrogen and possibly oxygen and helium too, and suggest that the gas is stellar wind and supernova ejecta condensed in the gravitational potential of the star cluster and is excited by ionizing stellar radiation. Based on the non-detection of flux time variability, which should be induced by intracluster microlensing effects but would be diluted if the source consists of many stars, the study suggests that Godzilla's magnification factor is lower than previously thought, in the range of hundreds. This casts doubt on the hypothesis that Godzilla's light is dominated by one or a few highly magnified stars.
See also
EMO J041608.838-240358.60, gravitationally-lensed binary star system nicknamed "Mothra"
List of star extremes
List of the most distant astronomical objects
Notes
References
Extragalactic stars
Gravitational lensing
Hubble Space Telescope
Apus | Godzilla (star) | [
"Astronomy"
] | 590 | [
"Apus",
"Constellations"
] |
71,916,023 | https://en.wikipedia.org/wiki/Tetraselenium%20tetranitride | Tetraselenium tetranitride is the inorganic compound with the formula . Like the analogous tetrasulfur tetranitride , is an orange solid. It is however less soluble and more shock-sensitive than .
As determined by X-ray crystallography, adopts a cage structure similar to that of . The Se−Se and Se−N distances are 2.740 and 1.800 Å, respectively. The N−Se−N angles are 90°.
Among its many reactions, reacts with aluminium chloride to form adducts of .
References
Explosive chemicals
Inorganic compounds
Nitrides
Eight-membered rings
Nitrogen heterocycles
Heterocyclic compounds with 3 rings
Selenium compounds | Tetraselenium tetranitride | [
"Chemistry"
] | 149 | [
"Explosive chemicals",
"Inorganic compounds"
] |
71,916,084 | https://en.wikipedia.org/wiki/Sunburst%20galaxy | The Sunburst galaxy is a strongly magnified galaxy at redshift z=2.38 (10.9 billion light years) behind the galaxy cluster PSZ1 G311.65-18.48.
The cluster acts as a power magnifier thanks to the gravitational lensing effect. The galaxy cluster distorts the space around it creating different paths for the photons coming from the Sunburst galaxy. This lensing creates four arc segment roughly following a circle around the foreground lensing cluster. Chance alignments of the Sunburst Galaxy and galaxies in the lensing cluster breaks up some of the arc segments into multiple smaller images, creating a total of 12 full or partial images of the galaxy along the arc; some of these images are magnified by very large factors. In one of these strongly magnified images of the Sunburst galaxy, astronomers have identified the most luminous star known to date, Godzilla. Another study suggests that Godzilla is a compact young massive star cluster that consists of thousands of bright stars and is magnified by a factor between about 500 and 2000. Emission from Godzilla's nebula indicates unusually pressurized ionized gas highly enriched with nitrogen.
The Sunburst galaxy hosts a massive star cluster that is only 2-4 Myr after formation. The star cluster is very compact, weighing tens of millions of solar masses while having a radius no larger than 10 parsecs. The star cluster is seen to be leaking ionizing radiation into the intergalactic space. In its vicinity, the star cluster excites a dense nebula that is enriched with nitrogen and is likely to have condensed from massive star wind material.
References
External links
The Sunburst Arc in SIMBAD
Galaxies
Gravitational lensing
Apus | Sunburst galaxy | [
"Astronomy"
] | 355 | [
"Galaxies",
"Apus",
"Astronomical objects",
"Constellations"
] |
71,916,572 | https://en.wikipedia.org/wiki/B%20cell%20growth%20and%20differentiation%20factors | B Cell Growth and Differentiation Factors (also known as BCGF and BCDF) are two important groups of soluble factors controlling the life cycle of B cells (also referred to as B lymphocytes, cells which perform functions including: antibody secretion, antigen presentation, preservation of memory for antigens, and lymphokine secretion). BCGFs specifically mediate the growth and division of B cells, or, in other words, the progression of B cells through their life cycle (cell cycle stages G1, S, G2). BCDFs control the advancement of a B cell progenitor or unmatured B cell to an adult immunoglobulin (Ig) secreting cell. Differentiation factors control cell fate and can sometimes cause matured cells to change lineage. Not all currently known BCGFs and BCDFs affect all B cell lineages and stages of the cell cycle in similar ways. Both BCGFs and BCDFs work on cells previously "activated" by factors such as anti-immunoglobulin (anti-Ig). BCGFs cause activated B cells to enlarge, express activation markers (ex. transferrin receptor) and enter the S phase (DNA synthesis phase) of the cell cycle. Meanwhile, BCDFs stimulate these cells to differentiate to mature Ig-secreting B cells.
An important note is that B cell Proliferation Factors (BCPFs) also exist and are different from BCGFs. BCPFs make cells, which are not necessarily activated, more responsive to BCGFs and help maintain cell viability, whereas BCGFs direct and stimulate growth and division. This article will mention BCPFs and factors that induce proliferation, yet the main focus will remain on BCGFs and BCDFs.
General Overview
The currently known BCGFs and BCDFs are BCGF I (also called B cell Stimulating Factor 1 (BSF1)), BCGF II, BCDF, IL-1 (interleukin-1), IL-2, IL-3, IL-4, IL-5, IL-6 (BSF-2), IFN-alpha, beta 2, and gamma, neuroleukin, TGF-beta (Transforming Growth Factor-beta), LP1 (Lymphopoetin 1), BCGFLOW, TNF-alpha (Tumor Necrosis Factor alpha), TRF (T cell Replacing Factor), CSF (colony-stimulating factors), MAF (macrophage activation factors), and lymphotoxin. Most factors act in many points throughout the B cell lifecycle, activation, growth, differentiation, and maturation, making this a complex pathway for study. Provided here is a list of these with some more detailed descriptions about their origins and functions.
BCGF I (BSF1 or BSFp1) - secreted by activated T cells. BCGF I induces "resting" cells to become susceptible to stimulation by ligands. Both anti-Ig and BCGF I are required for a cell to enter S and G2 phase. It is not clear if BCGF I acts on memory B cells specifically, but it appears to induce growth in the continuous presence of anti-Ig in all other lineages. BCGF is uninhibited by anti-Tac (T cell activation antigen), whereas other factors, such as IL-2 are.
BCGF II - a cytokine secreted by T cells.
BCDF - causes calcium influx in cells, critical for differentiation. It is the only factor which can achieve this effect. Induces differentiation in late-stage activated cells. BCDF subclasses are associated with the secretion of specific subclasses of Ig, for example BCDF(γ) with IgG and BCDF(μ) with IgM.
IL-1 - a cytokine derived from macrophages, this factor drives cells into S phase, usually working after BCGF I. IL-1 weakly co-stimulates even resting B cells in the presence of anti-Ig and can enhance BCDF function.
IL-2 - a cytokine key activating factor for T cells and B cells secreted by T cells. Cells in early-stage activation differentiate in response to IL-2 and all B cells proliferate in the presence of IL-2. IL-2 exhibits an additive affect to BCGF when both are present. Yet the magnitude of its effect is much less than BCGF and BCDF in both growth and differentiation.
IL-3 - cytokine associated with the differentiation of more mature B cells.
IL-4 - cytokine associated with the differentiation of mature T cells, which some B cell precursors are also responsive to.
IL-5 - cytokine that acts like IL-6, except it can also induce proliferation in B cells, and its effect on differentiation is partially inhibited by IL-4. IL-5 cannot induce differentiation in cells activated by anti-Ig.
IL-6 (BSF-2) - cytokine that acts exclusively as a B cell differentiation factor, stimulating increase in levels of Ig, J-chain mRNA, and proteins.
IFN-alpha, beta 2, and gamma (interferons alpha, beta 2, and gamma) - IFN-gamma in combination with IL-2 also induces early-stage differentiation. Interferon-gamma has previously been reported as a requirement for plaque-forming cell response. Interferon-alpha can either enhance or suppress differentiation by controlling responsiveness of human peripheral blood B cells to B-cell helper factors, depending on certain environment and context-specific conditions, as its signaling is likely mediated by other cell types.
Neuroleukin
TGF-beta
LP1 - a growth factor active in the development of immature B cells and capable of stimulating proliferation of B cell precursors.
BCGFLOW
TNF-alpha
TRF - induced primarily IgM secretion from B cells, thus constituting a differentiation factor. Various sources disagree as to whether TRF can induce proliferation.
CSF
MAF
Lymphotoxin
Discovery
The identification and classification of B cell growth and differentiation factors was primarily conducted in the 1980s-1990s, though it had begun to spark interest of the scientific community in the 1970s. It began with the creation of T cell hybridomas - immortal cells that could be selected to produce only one factor. This allowed the study of B cells exposed to only one soluble factor at a time, enabling the identification of that factor's direct effects on the cells. Previously, it was believed that B cell growth was induced exclusively by the presence of antigen. Some major questions that researchers attempted to answer were which cells and specifically cell types secreted these factors, and in which conditions, as well as if and how these factors differed from T Cell Growth and Differentiation Factors (TCGFs and TCDFs) such as IL-2. Additionally, it was established early on that several compounds could mediate B cell growth and differentiation, some of them working only when encountered together (synergistically). So, researchers also attempted to identify how many BCGFs and BCDFs exist and classify the varieties of these factors.
A major early challenge was the inability of culturing one distinctive T cell line or the isolation of thereof to analyze its effects. T cell factors that induced B cell activation, proliferation, growth, and differentiation were frequently generated by mixed populations of T cells. When the first immortalized T cell lines began to emerge, it became possible to observe which T cells had specific effects on B cells. Various T cell types secreted factors that induced Ig production, in some cases only of specific kinds or only in the presence of antigen. Some IgG classes secreted by B cells are exclusively T cell dependent.
Another major advance was the declaration that BCGF and BCDF were indeed two different entities. It was determined that T cell secreted factors and anti-Ig were necessary for the proliferation of activated B cells, while the addition of a differentiation factor was required to induce Ig production (ie. differentiation). So, it was determined that these two factors were separate entities. Isolating the two types of BCGF and BCDF was difficult as it required purification from IL-2. A key difference between the two variants of BCGF was that only one could induce growth in colony-forming B cells.
Later, difficulties with the subject B cell populations began to emerge, as there wasn't yet a stable long-term method of culture or isolation of individual subtypes. The difficulty of obtaining populations of viable B cell precursors was resolved by the design of a long-term bone marrow culture system, which secreted LP1 growth factor. In given populations, it was determined that B cells could be sorted into groups of "activated" and "resting" cells by their size, enabling the study of factors on these two distinct subgroups. As not all cell lines responded to the factors listed in the above section in similar ways (and some were completely irresponsive), a model cell line that could respond to various factors was necessary to compare the resulting responses and study in more detail the pathways of each lymphokine or factor's signal. Researchers identified several such cell lines that were guaranteed to have receptors for or respond to groups of factors. For example, in CH12 B cell lymphoma, cells differentiate in response to both IL-5 and IL-6 in the presence of other costimulatory cytokines, while in other cell lines IL-5 is only effective in a narrow window of time right after activation.
BCGFs and BCDFs were originally sought after for research purposes. Previously identified similar factors for T cells allowed T cells to be "immortalized" or kept alive in the research setting for prolonged periods of time. This permitted the extensive study of T cells and their functioning. It also permitted the modelling of the immune response, such as studying the activated T cell state. Finding factors that would enable a similar closer study of B cells would greatly benefit science.
B cell differentiation pathways
The most common simplified overview description of the B cell differentiation pathway involves the following steps: an antigen interacts with the corresponding surface membrane immunoglobulin after which the B cell begins expressing receptors for growth factors secreted by T cells (BCGFs and IL-2), after these factors bind, the lymphocytes enter S phase, and subsequent binding with BCDFs differentiates B cells into Ig secreting cells. This model quickly grows more complex as individual resting B cells receive multiple varying sequential signals that determine future cell fate and functions that will be performed by those cells. Depending on this sequence of BCDFs, B cells may achieve different "fates" which can constitute the types of Ig they secrete or even their destiny with a specialized lineage (such as Memory B cells or plasma cells).
Further investigations have been conducted since the identification of BCGFs and BCDF to determine what receptors they bind to and outline their pathways. There is evidence that CD23 is the receptor for BCDF. It was concluded that neither BCGF nor BCDF shared a receptor with IL-2. At least one pathway of B cell maturation via 446-BCDF, derived from anti-CD3 peripheral blood T cells, may involve reduction of intracellular cAMP. Stimulation by 446-BCDF causes an influx of calcium.
Immune system interactions
BCGFs and BCDFs primarily travel through the body intravenously but tend to be more concentrated in sites most critical to the human immune system - the lymph nodes, thyroid, spleen, bone marrow, and liver. The environments in all of these areas are complex ecosystems of various cell types, states, and concentrations of factors. So, in general, B cell activation, proliferation, and differentiation appears to be a complex process dependent on many cell and factor interactions as well as the state of activation of the cell.
The interconnected nature of the immune system has caused many complications, for when looking at cells in model systems, it has often been unclear which, if any, factor actually exerted their effects directly on the B cells themselves as opposed to acting via accessory cells or in conjunction with other factors.
Related diseases
Common diseases associated with the dysregulation of B cells are autoimmunity, immune deficiency, and various blood-associated cancers. BCGFs and BCDFs are associated with these diseases because they control crucial parts of the B cell life cycle - the cell's growth and identity. For example, if BCGFs are present at an extremely high concentration, cells may multiply very quickly exhibiting cancer-like behavior or extreme levels of immune response. Similarly, extreme differentiation towards a specific lineage may make the immune system weakened in some areas or too powerful and cause immune-related disease.
Different lineages or states of T cells secrete various BCDF subgroups. Maintaining the balance of the number and proportion of these cells is critical, as deficiencies in one or more subgroups cause disease, such as common variable immunodeficiency and chronic lymphocytic leukemia.
Dysregulation of growth factor production is a characteristic of some diseases such as rheumatoid arthritis, ankylosing spondylitis, systemic lupus erythematosus, and traumatic joint injury, where high levels of BCDF and IL-2 are present in the synovial fluid, resulting in increased differentiation of B lymphocytes into plasma cells and Ig secreting cells that secrete so many antibodies that they generate an immune response and inflammation in locations where they accumulate.
References
Further reading
Growth factors | B cell growth and differentiation factors | [
"Chemistry"
] | 2,827 | [
"Growth factors",
"Signal transduction"
] |
71,916,621 | https://en.wikipedia.org/wiki/Cell%20biomechanics | Cell biomechanics a branch of biomechanics that involves single molecules, molecular interactions, or cells as the system of interest. Cells generate and maintain mechanical forces within their environment as a part of their physiology. Cell biomechanics deals with how mRNA, protein production, and gene expression is affected by said environment and with mechanical properties of isolated molecules or interaction of proteins that make up molecular motors.
It is known that minor alterations in mechanical properties of cells can be an indicator of an infected cell. By studying these mechanical properties, greater insight will be gained in regards to disease. Thus, the goal of understanding cell biomechanics is to combine theoretical, experimental, and computational approaches to construct a realistic description of cell mechanical behaviors to provide new insights on the role of mechanics in disease.
History
In the late seventeenth century, English polymath Robert Hooke and Dutch scientist Antonie van Leeuwenhoek looked into ciliate Vorticella with extreme fluid and cellular motion using a simple optical microscope. In 1702 on Christmas day, van Leeuwenhoek described his observations, “In structure these little animals were fashioned like a bell, and at the round opening they made such a stir, that the particles in the water thereabout were set in motion thereby…which sight I found mightily diverting” in a letter. Prior to this, Brownian motion of particles and organelles within living cells had been discovered as well as theories to measure viscosity. However, there were not enough accessible technical tools to perform these accurate experiments at the time. Thus, mechanical properties within cells were only supported qualitatively by observation.
With these new discoveries, the role of mechanical forces within biology was not always naturally accepted. In 1850, English physician William Benjamin Carpenter wrote “many of the actions taking place in the living body are conformable to the laws of mechanics, has been hastily assumed as justifying the conclusion that all its actions are mechanical." Similarly, in 1917, Scottish mathematical biologist D'Arcy Wentworth Thompson noted “…though they resemble known physical phenomena, their nature is still the subject of much dubiety and discussion, and neither the forms produced nor the forces at work can yet be satisfactorily and simply explained” in his book On Growth and Form.
In the nineteenth century industrialization era, the overall understanding of the cell and tissue mechanics finally developed as it related to the mechanical, structural testing and theory (indentation, beam bending, the Hertz model) of engines, boats, and bridges. At the end of the nineteenth century, the mechanical properties of living cells were able to be experimentally analyzed and examined using techniques provided by large scale engineering mechanics. Since 2008, the nanoscale testing and modeling remains to be fundamentally based on these nineteenth century practices.
Research methods
Various studies have been conducted to establish relationships between the structure, mechanical responses, and function of biological tissues (blood vessels, heart, cardiac muscle, lung). To conduct this research, there have been several developed tools and techniques which are sensitive to detect such small forces. At this time, these techniques are only applicable in a controlled environment (test tube, petri dish). All of these methods ultimately give insight on mechanical properties of cells.
These techniques can generally be split up into two sections: active methods and passive methods. Active methods are methods that apply forces onto cells in some manner to deform the cell. Passive methods are methods that sense mechanical forces and do not apply any external forces to the cell.
Active methods
Atomic force microscopy
Atomic force microscopy is an interaction between a tip attached to a flexible cantilever and the molecule on a cell surface. The sharp tip can be used to probe single molecular events and image live cells. The relative deformation of the cell and the tip can be used to estimate how much force was applied and how stiff the cell is. Since it is a high force measurement technique, large scale deformations and reorganizations can be observed and mapped.
Some drawbacks of this technique include but are not limited to an overestimation of force-versus-indentation curve given no applied force, potential cell damage, variety of tip shapes that determine nature of force-deformation curve.
Magnetic tweezers and magnetic twisting cytometry
Magnetic twisting cytometry is mainly used to determine physical properties of biological tissues. They can also be used for micromanipulating cells.
Beads are exposed to magnetizing coils leading to a magnetic dipole moment. A weaker directional magnetic field is then applied to twist the beads through a specific angle or to move the beads lineary. Some disadvantages to this system include the difficulty to control the region of the cell that the beads, no guarantee of complete binding to the cell surface, and loss of magnetization with time.
A variation of this technique is named optical tweezers where linear forces are applied to cells rather than magnetic ones. A laser beam is used alongside dielectric beads of high refractive indices to generate optical forces. Drawbacks of this method include potential photo-induced damage and a limited amount of force that can be generated.
Micropipette aspiration
Micropipette aspiration is primarily used for measuring absolute values of mechanical properties. On a cellular scale, it can map in space and time surface tension of interfaces within a tissue. On a tissue scale, it can measure mechanical properties such as viscoelasticity and tissue surface tension. Like AFM, it is also a high force measurement technique, where large scale deformations and reorganizations can be observed and mapped.
A micropipette gets placed on the surface of the cell and gently suctions the cell to deform it. The geometry of the deformation along with the applied pressure allows researchers to calculate the force applied along with mechanical properties of the cell. A dual micropipette assay can is also able to quantify the strength of cadherin-dependent cell-cell adhesion.
Stretching devices
Stretching devices were developed to study effects of tensile stress on cells and tissues. Cells are incubated on flexible silicone sheet elastic membranes with modifiable surfaces. They are then stretched either in an uniaxial, biaxial, or pressure-controlled manner. The stretching can also occur at different frequencies. The main downside to stretching devices is that they leave behind wrinkling patterns, distorting the actual forces that were applied on the sheets. They are also large in size and generate both heat and shock, hindering the real-time imaging of cells.
Carbon fiber-based systems
Carbon fibers are mounted in glass capillaries and attached to a position-control device with feedback control mechanism. The fibers then attach to cells and apply and record the active forces generated from the cell. This, however, may result in damage to the cells due to the attachment they have to the fibers, focus issues, and potential bias.
Passive methods
Elastic substratum method
This method stems from the classical theory of small-strain, plane-stress elasticity. The elastic substratum method allows for analysis of the displacement field of the elastic substrate over the traction field. This method is also referred to as traction force microscopy.
Cells are incubated onto a flexible silicone sheet substrate. The cells then apply force onto the sheets causing a wrinkling pattern and is analyzed through the number of wrinkles and patterns. The downside to this method is the difficulty in transforming the patterns into a traction force map leading to potential inaccuracy in identifying forces.
Flexible sheets with embedded beads
Latex or fluorescently tagged beads are embedded into elastic substratum where the position of the beads are recorded over time. Cellular forces can be assumed by these displacements. The uncertainty with this method is the interdependence of bead displacement.
A more improved technique named flexible sheets with micropatterned dots or grids considers this drawback and instead has the dots imprinted onto the flexible sheet. The deformation of the grid from the original grid is then analyzed. The same assumptions, however, are required to be made where the forces originate from the measured location and do not spread from another area.
Micromachined cantilever beam
A horizontal cantilever beam with an attachment pad and a well is used to measure cell traction forces as cells are seeded onto substrates and crawl over the cantilevers. These cantilevers are set to measure force through cantilever deflection, stiffness, and stress gradient. Unlike the prior method, the uncertainty of no propagation is not an issue. Rather the cantilever beam can only move in only one direction leading to only one axis being measured.
The array of vertical microcantilevers is a technique that overcomes the limitations of the typical micromachined cantilever beam where there are two axes of directions available rather than a single horizontal beam. Although there is an improvement in scale and resolution, it is not suited for rapid- mass production and is quite costly. With delicate properties, minor damage would require reproduction of the device.
Applications and usage
In the last half-century, several studies have been conducted using cell biomechanics leading to greater biological control. Majority of these newly created devices are built to either provide greater insight into the human body’s reaction to disease or attempt to eradicate the disease as a whole.
Cardiovascular cell mechanics and microcirculation
Quantitative passive biomechanical models have been developed to predict cell motion and deformation in the mammalian red blood cell, a cell with a membrane with bending and shearing properties that are dependent upon strain, strain rate, and strain history, and a cytoplasm that in the normal red cell is predominantly a Newtonian viscous fluid, within a living organism. Newly developed (2007) models constitutive to this one show that biomechanical analysis not only is a starting point for prediction of the whole cell and cell suspension behavior, but also provides a reference point for molecular models of cell membranes that originate from the crystal structure of its parts.
Several generations of biomechanical models have also been developed for white blood cells, the basis of immune surveillance and inflammation. These models have been proven to effectively predict cell-cell interactions in microcirculation. Similar additional models have been created for endothelium, platelets and metastatic tumor cells.
Biomechanical analyses of different cell types in the circulation has brought greater understanding of cell interactions in the circulation, making it possible to predict cell behavior in narrow vessels. As a result, several blood diseases like inflammation and cardiovascular disease now have biomechanical footing. Models have also been developing in organs like the lung, heart, skeletal muscle, and connective tissue that are able to predict basic aspects of organ perfusion.
Cell enrichment and separation
From cell biomechanics, technology has been created to separate targeted cells. For the case of disease diagnosis and detection, said technology is able to separate healthy cells from cancerous ones through the difference in stiffness of the cell.
Deformability-based enrichment devices are an example of this technology. These devices mostly deal with cancer cells from blood. Their main feature is their ability to identify if cancer cells have separated themselves from the tumor and have entered into the bloodstream as CTCs (Circulating Tumor Cells). If they have, these devices have recently also become able to count the number of CTCs in a millimeter of blood. Using this value, medical professionals are able to determine the effectiveness of a chemotherapy treatment.
More specific examples include Clare Boothe Luce Assistant Professor of Mechanical Engineering at the Whiting School of Engineering Soojung Claire Hur’s microfluidic device and Woodruff School of Mechanical Engineering Professor Gonghao Wang’s microfluidic device that both deal with breast cancer cells. Hur’s device improves metastatic breast cancer cells by balancing deformability-induced and inertial lift forces that pushes larger metastatic cancer cells to move towards the centerline of a microchannel compared to blood cells. Wang’s device separates stiffer less invasive breast cancer cells by having diagonal ridges where only more deformable and highly invasive breast cancer cells can squeeze through.
Deformability-based enrichment devices, however, are not only exclusive to cancer cells. An example of this is Nanyang Technological University Researcher Han Wei Hou’s microfluidic device that separates and improves red blood cells from normal cells based on their stiffness through margination. Infected red blood cells are generally stiffer, so through his device, stiffer red blood cells would be closer to the vessel wall when normal red blood cells would stay in the center. This allows the deformed red blood cells to be collected via a separate outlet on the sides.
Ongoing research concerns
In the 1800’s, cells were initially thought to be of homogeneous gels, sols, viscoelastic and plastic fluids. Models currently have been developed into including a viscoelastic continuum, a combination of discrete mechanical elements, or a combination of viscoelastic fluid within a dense meshwork and have been proven to be highly accurate after experimentation. Despite these improved and more refined models, there still remain to be flaws as several experimental proofs (soft glass rheology rheology phenomenon) that refute current existing models. Thus, the time-dependent and predictive theoretical description of cell mechanics remains to be incomplete.
It is also not fully understood whether mechanical phenomena are side products of biological processes or they are controlled at the genetic and physiological level through feedback loops, actuation and response pathways given our existing knowledge of cell physiology or neurophysiology.
References
Biomechanics | Cell biomechanics | [
"Physics"
] | 2,775 | [
"Biomechanics",
"Mechanics"
] |
71,916,640 | https://en.wikipedia.org/wiki/List%20of%20Art%20Deco%20architecture%20in%20North%20Carolina | This is a list of buildings that are examples of the Art Deco architectural style in North Carolina, United States.
Asheboro
Acme-McCrary Corporation, Asheboro, 1940s
Asheboro Hosiery Mill No, 2, Asheboro, 1945
Randolph Hospital, Asheboro, 1932
Asheboro Municipal Building, 1938
Asheville
Asheville City Hall, Asheville, 1928
Asheville High School, Asheville, 1927
Asheville Transfer and Storage Company Building, Asheville, 1929
Bon Marche Department Store (now Earth Guild), Downtown Asheville Historic District, Asheville, 1937
Clarence Barker Memorial Hospital, Asheville, 1929
Coxe Building, Asheville, 1930
F. W. Woolworth Building, Downtown Asheville Historic District, Asheville, 1939
Fire Station No. 4, Asheville, 1927
First Baptist Church, Asheville, 1927
Flatiron Building, Downtown Asheville Historic District, Asheville, 1925
Haverty Furniture Building, Asheville, 1928
Isis Music Hall, West Asheville End of Car Line Historic District, Asheville, 1937
Kress Emporium (former S. H. Kress and Co. Building), Asheville, 1927
McGeahy Building, West Asheville–Aycock School Historic District, Asheville, 1934
S&W Cafeteria, Asheville, 1929
Shell Filling Station (now jewelers), Asheville, 1928
The Strand (now Fine Arts Theater), Asheville, 1946
United States District Court for the Western District of North Carolina, Asheville, 1929
Charlotte
American Legion Memorial Stadium, Charlotte, 1934
Barringer Hotel, Charlotte, 1940 and 1950
Century Building, Charlotte, 1926
Charlotte Coca-Cola Bottling Company Plant, Charlotte, 1930
Crane Company Building, Charlotte, 1928
Mecklenburg Investment Company Building, Charlotte, 1922
Durham
333 West Main, Durham
Clark and Sorrell Garage, Durham, 1932 and 1941
Crowe Building, American Tobacco Historic District, Durham, 1953
East Durham Junior High School (now Holton Career & Resource Center), Durham, 1939
Fowler Building, Durham American Tobacco Historic District, Durham, 1939
Herald-Sun Building, Durham, 1930
Hill Building, Durham, 1937
Liggett Office Building, Durham, 1920, 1946
Royal Crown Cola – 7up Bottling Company Building, Durham, 1939
S. H. Kress and Co. Building, Durham, 1933
Scott and Roberts Dry Cleaning Plant, Office, and Store, Durham, 1947
Snow Building, Durham, 1933
Strickland Building, Durham American Tobacco Historic District, Durham, 1946
Weeks Motor Company/Hutchin's Auto Supply, Durham, 1948
Elizabeth City
Selig Building, Elizabeth City Historic District, Elizabeth City, 1925
Sheep–Harney Auditorium, Northside Historic District, Elizabeth City, 1950s
S. L. Sheep School, Northside Historic District, Elizabeth City, 1940
Gastonia
S. H. Kress and Co. Building, Downtown Gastonia Historic District, Gastonia, 1930
United States Post Office, Downtown Gastonia Historic District, Gastonia, 1935
Webb Theatre, Gastonia, 1930
Greensboro
Ellis-Stone Building/Thalimer Department Store, Downtown Greensboro Historic District, Greensboro, 1906 and 1930s
Guilford County Office and Court Building, Greensboro, 1937
International Civil Rights Center and Museum (former F. W. Woolworth Building), Greensboro, 1939
Isaacson Building, Downtown Greensboro Historic District, Greensboro, 1900 and 1930s
L. Richardson Preyer Federal Building, Greensboro, 1933
Mock, Judson, Voehringer Company Hosiery Mill, Greensboro, 1926
S. H. Kress and Co. Building, Greensboro, 1929
Greenville
Bissette's Drug Store, Greenville Commercial Historic District, Greenville, 195
Greenville Municipal Building, Greenville Commercial Historic District, Greenville, 1939
L. M. Ernst Son & Company Building, Dickinson Avenue Historic District, Greenville, 1946
Lautares Brothers Building, Greenville Commercial Historic District, Greenville, 1940
Montgomery Ward Department Store, Greenville Commercial Historic District, Greenville, 1929
Roxy Theatre, Greenville, 1948
Smith Electric Building, Greenville Commercial Historic District, Greenville, 1920 and 1933
Star Warehouse, Greenville Tobacco Warehouse Historic District, Greenville, 1930
Hamlet
Old Hamlet Opera House, Main Street Commercial Historic District, Hamlet, 1912 and 1927
Subway Stations, Main Street Commercial Historic District, Hamlet, 1940
Union Building, Main Street Commercial Historic District, Hamlet, 1920
Kinston
Carolina Theatre, Kinston Commercial Historic District, Kinston, 1935
Community Council for the Arts (former Kinston Garage), Kinston Commercial Historic District, Kinston, 1936
Hotel Kinston, Kinston, 1928
Lenoir County Courthouse, Kinston, 1939
Standard Drug No. 2, Kinston, 1924
Lenoir
Caldwell County Courthouse, Lenoir, 1929
Center Theatre, Lenoir Downtown Historic District, Lenoir, 1941
O. P. Lutz Furniture Company and Lutz Hosiery Mill, Lenoir Downtown Historic District, Lenoir, 1939
Mount Airy
Earle Theatre, Mount Airy Historic District, Mount Airy, 1938
Masonic Temple, Mount Airy Historic District, Mount Airy, 1931
United States Post Office, Mount Airy Historic District, Mount Airy, 1932
Workman's Federal Savings and Loan, Mount Airy Historic District, Mount Airy, 1891 and 1930s
Raleigh
Capital Club Building, Raleigh, 1929
Carolina Power and Light Company Car Barn and Automobile Garage, Raleigh, 1925
CP & L Garage (now a tire shop), Raleigh, 1925
Pine State Creamery, Raleigh, 1928
Raleigh Water Works and E.B. Bain Water Treatment Plant, Raleigh, 1939
Royal Baking Company, Raleigh, 1941
Rocky Mount
122 Howard Street commercial building, Rocky Mount, 1930s
625 Sunset Apartments, Rocky Mount, 1945
Baldwin Department Store, 100 NW Main, Rocky Mount
CenturyLink Building (former Carolina Telephone & Telegraph Building), Rocky Mount Central City Historic District, Rocky Mount, 1948
former Downtown Wig Market, 100 NW Main, Rocky Mount, 1910, 1940
Firestone Stores Building, Rocky Mount Central City Historic District, Rocky Mount, 1930
former Grand Theatre, Rocky Mount, 1912, 1930s
James Craig Braswell School, Rocky Mount, 1940
Manhattan Theatre, Rocky Mount Central City Historic District, Rocky Mount, 1935
Memorial Hospital, Rocky Mount, 1937
Ritz Theatre, 150 E. Thomas, Rocky Mount, 1950
former Rosenbloom-Levy store, 146 Southwest Main, Rocky Mount, 1905, 1930s
Winston-Salem
Pepper Building, Winston-Salem, 1928
Reynolds Building, Winston-Salem, 1929
Sosnik-Morris-Early Commercial Block, Winston-Salem, 1929
Other cities
Atlantic Bank and Trust Company Building, Burlington, 1928
B&S Department Store, Downtown Wake Forest Historic District, Wake Forest, 1894 and 1949
Belmont Junior High (former Belmont High School), Belmont Historic District, Belmont, 1939
Ben's of Wake Forest Building, Downtown Wake Forest Historic District, Wake Forest, 1940
Bladen County Recreation Center (former Gymnasium), Elizabethtown, 1940
City Hall (former United States Post Office and Federal Building), Reidsville Historic District, Reidsville, 1926
City Hall, Marion, 1937
City Hall, Williamston Commercial Historic District, Williamston, 1960
Co-Ed Cinema, Brevard, 1939
County Armory, Eden, 1939
Davis Sisters Building, Main Street Historic District, Forest City, 1932
DeHart Building, Leaksville Commercial Historic District. Eden, 1930
Don Gibson Theater, Shelby, 1939
Enterprise Building, High Point, 1935
Esso Gas Station, Four Oaks Commercial Historic District, Four Oaks, 1957
Fire Department Headquarters, Goldsboro, 1939
Garrou-Morganton Full-Fashioned Hosiery Mills, Morganton, 1927–1928
Gem Theater, Kannapolis, 1936
Gibson Theatre, Laurinburg Commercial Historic District, Laurinburg, 1940
Graham Cinema, Graham, 1933
Griffin Theatre, West Main Street Historic District, Forest City, 1948
Hosiery Mill (former Dexdale Hosiery Company), Penderlea Homesteads Historic District, Willard, 1938
Howell Theatre, Downtown Smithfield Historic District, Smithfield, 1935
Joy Lee Apartment Building and Annex, Carolina Beach, 1945
Kirby Cultural Arts Complex (former Kirby Theatre), Roxboro Commercial Historic District, Roxboro, 1949
Lawsonville Avenue Elementary School, Reidsville, 1935
Lexington Memorial Hospital, Lexington, 1946
Liberty Theatre, Downtown Main Street Historic District, North Wilkesboro, 1946
M & O Chevrolet Company, Fayetteville, 1937
Masonic Temple Building, Shelby, 1924
Mimosa Theatre, Morganton Downtown Historic District, Morganton, 1939
Municipal Building (former Gabriel Johnston Hotel), Downtown Smithfield Historic District, Smithfield, 1937
North Wilkesboro Police Department (former Town Hall), Downtown Main Street Historic District, North Wilkesboro, 1939
Old Wilkesboro Municipal Building, Downtown Wilkesboro Historic District, Wilkesboro, 1930s
O'Neil Building, Henderson Central Business Historic District, Henderson, 1885 and 1929
Orpheum Theatre, Oxford, 1942
Paramount Theatre, Farmville Historic District, Farmville, 1919 and 1933
Parkway Theater, West Jefferson Historic District, West Jefferson, 1939
Pepsi Bottling Company, West Selma Historic District, Selma, 1935
Plymouth Theatre, Plymouth Historic District, Plymouth, 1937
Police Department Building (former City Hall), Thomasville, 1938
Rose's Dime Store Building, Canton Main Street Historic District, Canton, 1930
Roxy Theatre (now a hardware store), Old Fort Commercial Historic District, Old Fort, 1946
Salisbury Building, Salisbury, 1928
Sampson Community Theatre (former Clinton Theatre), Clinton Commercial Historic District, Clinton, 1950
Siler City High School, Siler City, 1922
Smith Clinic, Thomasville, 1939
Starnes Jewelers, Albemarle, 1920s
Temple Theatre, Sanford, 1925
Turnage Building, Ayden Historic District, Ayden, 1947
United States Post Office, Burlington, 1936
United States Post Office and Federal Building, Rockingham, 1936
Watkins Building/Parker Drugstore, Henderson Central Business Historic District, Henderson, 1885 and 1930s
Wilson Habitat Store (former Lovelace Motor Company), Wilson Central Business–Tobacco Warehouse Historic District, Wilson, 1937
Wilson Municipal Building, Wilson, 1935
WPTF Radio Transmitter, Cary, 1934
Yancey Country Schools District Office (former Gymnasium), Burnsville, 1930s
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.
"North Carolina Architects & Builders : NCSU Libraries". Retrieved 2019-01-03.
"Home | Open Durham"Retrieved 2020-09-25.
"SAH Archipedia". Society of Architectural Historians. Retrieved 2021-11-21.
External links
Art Deco
Lists of buildings and structures in North Carolina | List of Art Deco architecture in North Carolina | [
"Engineering"
] | 2,194 | [
"Architecture lists",
"Architecture"
] |
71,916,758 | https://en.wikipedia.org/wiki/List%20of%20Art%20Deco%20architecture%20in%20Indiana | This is a list of buildings that are examples of the Art Deco architectural style in Indiana, United States.
Evansville
325 Main Street (former J. H. Schultz Shoes), Evansville, 1909 and 1940s
Bosse Field, Evansville, 1915
Cambridge Arms Apartments, Evansville, 1920
Children's Museum of Evansville, Evansville, 1931
Evansville Civic Theatre (former Columbia Theatre), Evansville, 1910 and 1939
Firestone Tire and Rubber Store, Evansville, 1930
Greyhound Bus Terminal, Evansville, 1938
Hulman Building, Evansville, 1928
Indiana Bell Building, Evansville, 1929
Lincoln School, Evansville, 1928
Lynch School (now law offices), Evansville, 1930
Old Fellwock Auto Company, Evansville, 1922
Vectren Power Substation (former SIGECO substation), Evansville, 1935
Zuki Restaurant (former a bank), Evansville, 1940
Fort Wayne
3414 Fairfield, Fort Wayne, 1940
AT&T Building (former Indiana Bell Telephone Company Exchange Building), Fort Wayne, 1932
E. Ross Adair Federal Building and United States Courthouse, Fort Wayne, 1932
Goodrich Silvertown Tire and Service Station, Fort Wayne, 1930
Harry L. Soshea House, 930 Prange, Fort Wayne, 1936
Indiana State Highway Garage, Fort Wayne, 1938, 1968
Lewis Bakeries (former Holsum Bakery Company), Fort Wayne, 1928 and 1948
Lincoln Bank Tower, Fort Wayne, Indiana, 1930
MacDougal Memorial Chapel, Fort Wayne
North Manufacturing Building, 730 Growth, Fort Wayne, 1923
REA Magnet Wire Company (former INCA Company Building), Fort Wayne, 1928
Strebig Construction Building, Fort Wayne, 1958
Trinity Hall, University of St. Francis, Fort Wayne, 1948
Zollner Piston Company, Fort Wayne, 1931
Indianapolis
333 Penn (former Architects and Builders Building), Indianapolis, 1912 and 1929
3762 North Meridian Street, Shortridge–Meridian Street Apartments Historic District, Indianapolis, 1948
The Admiral, Indianapolis, 1929
The Alameda, Indianapolis, 1925
Bauer Apartments, Shortridge–Meridian Street Apartments Historic District, Indianapolis, 1937
Bottleworks Hotel (former Coca-Cola Bottling Plant), Indianapolis, 1920, 1949
Bush Stadium, Indianapolis, 1931
Circle Tower, Indianapolis, 1930
Clinical Building, Indiana University, Indianapolis, 1936
Cole Motor Car Company Building, Indianapolis, 1913
The Garage Food Hall, Indianapolis, 1949
H. P. Wasson and Company, Indianapolis, 1937
Indiana Oxygen Company building, Indianapolis, 1930
Indiana State Library and Historical Bureau, Indianapolis, 1934
Indiana World War Memorial Plaza, Indianapolis, 1924
Kassebaum Building, Indianapolis, 1928
Madam Walker Legacy Center, Indianapolis, 1927
The McKay, Indianapolis, 1924
Old Trails Automobile Insurance Association, Indianapolis, 1928
Sears, Roebuck & Co. Building, Indianapolis, 1929
Shortridge Apartments, Shortridge–Meridian Street Apartments Historic District, Indianapolis, 1938
Willow Marketing Building, Shortridge–Meridian Street Apartments Historic District, Indianapolis, 1958
New Haven
621 Broadway Street, New Haven, 1925
Navy Club (former Arrington Theatre, Broadway Theatre), New Haven, 1930 and 1945
New Haven Adams Township Fire Department Station 1, New Haven
Shelbyville
Coca-Cola Bottling Company, Shelbyville, 1930
First United Methodist Church, Shelbyville, 1920
Grover Center Museum and Historical Society (former Elk's Lodge), Shelbyville, 1940
Lora B. Pearson School, Shelbyville, 1939
Porter Pool Bathhouse, Shelbyville, 1930
Shelby County Courthouse, Shelbyville, 1937
Shelby Tire & Auto Care, Shelbyville
South Bend
1000 Sample Street (former Wilson Brothers), South Bend, 1920
1008 Lincolnway East, South Bend, 1925
1011 Main Street, South Bend, 1924
1237 Western Avenue, South Bend, 1914
303 Chapin Street, South Bend, 1922
407 Lincolnway West Apartments, South Bend, 1930
Farmers Security Building, 133 South Main Street, South Bend, 1915
Fire Station No. 4, South Bend, 1920
Hoffman Hotel Apartments, South Bend, 1930
I & M Building, South Bend, 1929
Indiana Fencing Academy/Escrime du Lac Fencing Club, South Bend, 1950
Jefferson Place, South Bend, 1920
John Adams High School, South Bend, 1940
Kaniewski Building, 1201 Western Avenue, South Bend, 1914
Marquette School, South Bend, 1937
NIPSCO Gas Building, South Bend, 1940
PTL Tire Company, South Bend, 1930
Robert A. Grant Federal Building and U.S. Courthouse, South Bend, 1933
Rozplochowski Furniture, 1237 Western Avenue, South Bend, 1914
South Bend Chocolate Company (former John Baungarth Company), South Bend, 1929
South Bend Tribune Building, South Bend, 1922
State Theatre, South Bend, 1934
That Church Downtown (former Salvation Army), South Bend, 1946
Twin City Building, South Bend, 1928
Union Station, South Bend, 1929
W. R. Hinkle and Company, South Bend, 1922
Terre Haute
1246 Maple Avenue, Twelve Points Historic District, Terre Haute,
AT&T Building (former Indiana Bell Building), Wabash Avenue–East Historic District, Terre Haute, 1940
Citizens' Trust Company Building, Terre Haute, 1922
Columbian Enameling and Stamping Company, Terre Haute, 1940
Indiana Landmarks Western Regional Office (former Terre Haute Mutual Savings Association), Terre Haute, 1941
McCalister Brothers Construction (former Merchants Freight company), Terre Haute, 1945
National Building, Terre Haute, 1934
RiverFront Lofts (former American Can Company, Pillsbury), Terre Haute, 1930
Stalker Hall (now College of Arts and Sciences, Indiana State University), Terre Haute, 1954
Swope Art Museum, Terre Haute, 1942
Terre Haute Post Office and Federal Building, Terre Haute, 1933
Versailles
Gibson Theatre, Versailles, 1921 and 1929
Tyson United Methodist Church, Versailles, 1937
Versailles School and Tyson Auditorium, Versailles, 1938
Other cites
210 East Washington Street, Hartford City Courthouse Square Historic District, Hartford City, 1940
American Steam Laundry Building, Washington Commercial Historic District, Washington, 1930
Anderson Bank Building, Anderson, 1928
Armco-Ferro House, Century of Progress Architectural District, Beverly Shores, 1933
Artcraft Theatre, Franklin, 1922
Astra Theatre, Jasper, 1936
Auburn Cord Duesenberg Automobile Museum, Auburn, 1930
Buskirk-Chumley Theatre, Bloomington, 1934
Central Fire Station, Columbus, 1941
Coca-Cola Bottling Plant, Bloomington, 1924
Colgate Factory, Jeffersonville, 1921
Cooper Theater, Brazil Downtown Historic District, Brazil, 1947
The Crump Theatre, Columbus, 1889 and 1941
Decatur Township Junior High School, Decatur, 1938
Devon Theater, Attica Downtown Historic District, Attica, 1938
Eger Grocery Building, Rensselaer Courthouse Square Historic District, Rensselaer, 1930
Forest Hill Cemetery Abbey, Greencastle, 1931
Fountain County Courthouse, Covington, 1937
Fowler Theatre, Fowler, 1940
Haggar Hall, Saint Mary's College, Notre Dame, 1936
Honeywell Center, Wabash, 1941–1952
Howard County Courthouse, Kokomo Courthouse Square Historic District, Kokomo, 1937
L. Fish Furniture Building, State Street Commercial Historic District, Hammond, 1927
Peabody Memorial Tower, North Manchester, 1937
Peru High School, Peru High School Historic District, Peru, 1939
Pickwick Theatre, Syracuse, 1947
Riley Hall, University of Notre Dame, Notre Dame, 1920
Salvation Army, Bedford, 1930s
Scheidler Theatre, Hartford City Courthouse Square Historic District, Hartford City, 1947
Sowers & Gough Drugstore, Hartford City Courthouse Square Historic District, Hartford City, 1910 and 1940
Temple Theatre, Mishawaka, 1916
Times Theatre (former Char-Belle Theatre), Rochester, 1924
Tower Hotel, Anderson, 1930
Wigwam Mineola Tribe No. 86 Building, Franklin, 1920s
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.
"Welcome to SHAARD". Indiana State Historic Architectural and Archaeological Research Database Retrieved 2022-03-19.
External links
Art Deco
Lists of buildings and structures in Indiana | List of Art Deco architecture in Indiana | [
"Engineering"
] | 1,704 | [
"Architecture lists",
"Architecture"
] |
71,916,794 | https://en.wikipedia.org/wiki/HD%2031529 | HD 31529, also known as HR 1584, is a solitary, orange hued star located in the southern constellation Caelum, the chisel. It has an apparent magnitude of 6.09, making it faintly visible to the naked eye if viewed under ideal conditions. This object is located relatively far at a distance of 932 light years based on parallax measurements from Gaia DR3, but is receding with a heliocentric radial velocity of . Eggen (1989) lists it as a member of the old disk population.
This is an evolved red giant star with a stellar classification of K3 III. It is currently on the red giant branch, generating energy by fusing hydrogen in a shell around its core. It has 4.8 times the mass of the Sun and an enlarged radius of due to its evolved state. It radiates 915 times the luminosity of the Sun from its photosphere at an effective temperature of . HD 31529 is slightly metal deficient (76% solar iron abundance) and spins modestly with a projected rotational velocity of .
References
Caelum
K-type giants
31529
1584
CD-39 01691
022847
13883466
Caeli, 22 | HD 31529 | [
"Astronomy"
] | 254 | [
"Caelum",
"Constellations"
] |
71,916,885 | https://en.wikipedia.org/wiki/List%20of%20Art%20Deco%20architecture%20in%20Colorado | This is a list of buildings that are examples of the Art Deco architectural style in the U.S. State of Colorado.
Aurora
Aurora Fox Arts Center, Aurora, 1946
Fitzsimons Army Medical Center, Aurora, 1941
KOA Building, Aurora, 1932
Boulder
Boulder County Courthouse, Boulder, 1933
Boulder Theater, Boulder, 1906, 1935
Boulder High School, Boulder, 1937
Glen Huntington Band Shell, Boulder, 1938
Colorado Springs
Colorado Springs Fine Arts Center, Colorado Springs, 1936
Colorado Springs School District 11 Administration Building, Colorado Springs
General William J. Palmer High School, Colorado Springs, 1940
Kimball's Peak Three Theater (former Peak Theater), Colorado Springs, 1935
Morrison Brothers Market, Colorado Springs, 1936
Municipal Utilities Building, Colorado Springs, 1931
Peterson Air and Space Museum, Colorado Springs, 1942
Denver
1575 Vine, Denver, 1947
2383 Jasmine Street, Denver, 1939
A. B. Hirschfeld Press Building, Denver, 1949
American Woodmen Life Building, Denver, 1950
Bluebird Theater, Denver, 1914
Bryant Webster Elementary School, Highland, Denver, 1931
Buerger Brothers Building, Denver, 1929
Colorado Coalition for the Homeless, Denver 1930s
Colorado State Capitol Annex Building and Boiler Plant, Capitol Hill, Denver, 1939
Denver Wastewater Management Building, Denver, 1993
Detroit Terraces, Denver
Dorset House, Denver, 1937
The Elm, Denver, 1930s
Emerson Apartments, Poet's Row, Denver, 1930s
Emily Dickinson Building, Poet's Row, Denver, 1956
Eugene Field Building, Poet's Row, Denver, 1939
Fire Station No. 11, Denver, 1937
Horace Mann Middle School, Denver 1931
Hotel Monaco (former Albany Hotel), Denver, 1930s
James Russell Lowell Building, Poet's Row, Denver, 1936
Katherine Mullen Memorial Home for Nurses (now Mullen Building, Saint Joseph Hospital Foundation), Denver, 1936
Leeman Auto Company Building, Denver, 1932
Leetonia Apartments, Denver, 1930
Louisa May Alcott Building, Poet's Row, Denver, 1931
Marianne Apartments, Denver, 1930s
Mark Twain Apartments, Poet's Row, Denver, 1937
Mayan Theater, Denver, 1930
Midwest Steel & Iron Works, Denver, 1930
Mountain States Telephone Building, Denver, 1929
Nathaniel Hawthorne Building, Poet's Row, Denver, 1938
Nordlund House, Denver, 1939
Oxford Hotel Cruise Room, Denver, 1891 and 1933
Paramount Theatre, Denver, 1930
Railway Exchange New Building, Denver, 1937
Robert Browning Apartments, Poet's Row, Denver, 1937
Robert Frost Building, Poet's Row, Denver, 1929
Robert W. Steele Elementary School, Denver 1929
Rose-Adell Apartments, 970 Pennsylvania, Denver, 1940
Shangri-La, Denver, 1938
Sherman Arms Building, Poet's Row, Denver, 1950
Smiley's Laundromat, Denver, 1932
Thomas Carlyle Building, Poet's Row, Denver, 1936
University Building, Denver, 1929
Washington Irving Apartments, Poet's Row, Denver, 1936
Fort Collins
Beebe Clinic Building, Fort Collins
Fort Collins Municipal Power Plant Fountain, Fort Collins, 1936
Northern Hotel, Fort Collins, 1936
Student Services Building, Colorado State University, Fort Collins, 1948
Fort Morgan
Farmers State Bank Building, Fort Morgan, 1930
Fort Morgan Fire Department, Fort Morgan
Fort Morgan Power Plan, Fort Morgan, 1952
Morgan County Courthouse and Jail, Fort Morgan, 1921 and 1936
Lakewood
Davies Chuck Wagon Diner, Lakewood, 1957
Ethel's Beauty Salon and Gil's Barber Shop, Heritage Lakewood Belmar Park, Lakewood
Jeffco Open High School, Lakewood
Lakewood Theatre, Lakewood, 1948
Peerless Gas Station, Heritage Lakewood Belmar Park, Lakewood
Sno White Dry Cleaners, Lakewood, 1948
Sobesky Academy, Lakewood
Other cities
Benevolent and Protective Order of Elks Lodge, Montrose, 1927
Burlington Gymnasium, Burlington, 1941
Chaffee County Courthouse, Salida, 1931
Chaka Theater, Julesburg, 1919
Cliff Theater, Wray, 1950
Custer County Courthouse, Westcliffe, 1929
Del Norte Grade School, Del Norte, 1942
Eagle County Courthouse, Eagle
Egyptian Theatre, Delta, 1933
Fruita Middle School, Fruita
Gothic Theatre, Englewood, 1920s
Greeley Junior High School, Greeley, 1938
Haskin Medical Building, Center, 1940s
Heister House, Salida, 1943
Hugo Municipal Pool, Hugo, 1938
Husung Hardware Building (now KENY TV), Alamosa, 1936
Isis Theater, Victor, 1896, 1920s
Kim Schools, Kim, 1934
La Jara Elementary School, La Jara, 1930s
Lakeside Amusement Park, Lakeside, 1930s
Lamar Theater, Lamar, 1920
Montrose City Hall, Montrose, 1926
Municipal Building, Gunnison, 1931
Phillips County Courthouse, Holyoke, 1935
Rialto Theater, Loveland, 1920
Revere High School, Ovid, 1928
S. H. Kress and Co. Building, (now Business and Technology Center), Pueblo, 1930
St. Agnes Catholic Church, Saguache, 1950
Sedgwick County Courthouse, Julesburg, 1939
Sim Hudson Motor Company Building, Burlington, 1932
Trojan Theater, Longmont, 1939
Union High School, Westminster, 1939
United States Post Office, Florence, 1936
Ute Theatre, Saguache, 1916
See also
:Category:Art Deco architecture in Colorado
List of Art Deco architecture
List of Art Deco architecture in the United States
Bibliography of Colorado
Geography of Colorado
History of Colorado
Index of Colorado-related articles
List of Colorado-related lists
Outline of Colorado
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.
"New York Registry & Map – Art Deco Society of New York". Archived from the original on 2019-01-03. Retrieved 2019-01-03
"SAH Archipedia". Society of Architectural Historians. Retrieved 2021-11-21.
External links
Architecture lists
Lists of buildings and structures in Colorado | List of Art Deco architecture in Colorado | [
"Engineering"
] | 1,256 | [
"Architecture lists",
"Architecture"
] |
71,917,035 | https://en.wikipedia.org/wiki/Engineer%20Troops%20%28Soviet%20Union%29 | Engineer Troops of the USSR — were special troops of the Soviet Armed Forces, designed for military engineer support: combat operations; engineering reconnaissance, and escort of troops (forces) in the offensive, and so on.
The main purpose of military engineers is operational support during combat: mobility/countermobility. Engineering support for the military (combat) operations of the troops aims to create the necessary conditions for the troops covertly move forward, in a timely fashion, deploy, manoeuvre, successfully carry out combat missions, protect troops and facilities from all types of damage, inflict losses on the enemy, and to impede enemy actions.
History
After the February and October Revolutions of 1917, during the organization of the Red Army and the fleet, sapper units of the former Russian Imperial Army were merged into the Red Army. In 1919, pontoon and electrical battalions, automobile units, camouflage companies, and a mine-blasting brigade were created. By 1929, the general formation of engineering troops in the Red Army was completed.
On 22 June 1941, Germany invaded the Soviet Union in Operation Barbarossa. In October 1941, the post of chief of the Engineering Troops was established. During the course of the war, engineer troops built fortifications, created barriers, mined the terrain, ensured the maneuver of troops, made passages in enemy minefields, ensured the overcoming of enemy engineering barriers, forcing water barriers, participated in the assault on fortifications, cities, etc. During the Second World War, 10 sapper armies were created, later reorganized into brigades.
V.I. Feskov et al 2013 lists 11 pontoon-bridge and 76 engineer sapper brigades in the Red Army in 1946, including the 1st Guards, 2nd Guards, 3rd Guards, 4th, 5th, and 6th Guards engineer brigades and other engineer brigades (including the 52nd, 55th, 56th, 57th, 61st, 62nd, 63rd, 64th, 65th, 67th, 68th, 69th, and 70th).
From the mid-1940s to the 1970s, motorized rifle regiments included engineer-sapper companies (иср), in divisions - engineer-sapper battalions (исб), in combined-arms armies and districts - engineering and sapper regiments (исп), as well as specialized battalions and regiments: pontoon-bridge, crossing-landing, road, bridge-building, etc. However due to planning miscalculations, the Soviet invasion of Afghanistan (1979–89) had a shortage of engineer units.
V.I. Feskov et al 2013 lists 26 regiments of engineer forces as existing during the 1980s, including the 1st Guards, 174th, and 177th. There were also three road construction corps and 25 road construction brigades seemingly active as part of the Road Troops.
In 1986, the Engineering Troops took part in the military response to the biological effects of the Chernobyl accident. After the collapse of the USSR in late 1991, the Engineering Troops were dissolved and its component units were split, becoming the Russian Engineer Troops, as well as being absorbed by the newly formed Armed Forces of Ukraine, Armed Forces of Belarus, Armed Forces of the Republic of Kazakhstan, Armenian Armed Forces, and others.
Tasks
According to the Combat Regulationss of the Soviet Ground Forces, engineering support includes:
engineering reconnaissance enemy, terrain and objects;
fortification equipment of positions, lines, districts, command posts;
device and maintenance of engineering barriers, and the production of destruction;
installation and maintenance of nuclear mines and land miness;
destruction and neutralization of enemy nuclear mines;
making and maintaining passages in barriers and destruction;
the device of passages through obstacles;
clearance of terrain and objects;
preparation and maintenance of troop movement routes, transportation and evacuation;
equipment and maintenance of crossings when forcing water barriers;
engineering measures to camouflage troops and facilities;
engineering measures to restore the combat capability of troops and eliminate the consequences of enemy nuclear strikes;
extraction and purification of water, equipment of points of water supply.
The Engineer Troops performed engineering support missions that required special training of personnel, the use of engineering Equipment and engineer ammunition. In addition, their tasks include defeating enemy equipment and manpower with mine-explosive and nuclear-mine weapons.
Commanders
1942-1952 - Marshal of the Engineering Troops Vorobiev, Mikhail Petrovich;
1952-1965 - Colonel General (from 05/06/1961 - Marshal) of the Engineering Troops Proshlyakov, Alexei Ivanovich;
1965-1975 - Lieutenant General (from 05/07/1966 - Colonel General, from 12/16/1972 - Marshal) of the Engineering Troops Kharchenko, Viktor Kondratievich;
1975-1987 - lieutenant general (from 04/25/1975 - colonel general, from 05/07/1980 - Marshal) of the Engineering Troops Aganov, Sergey Khristoforovich;
1987-1999 - Lieutenant General (since February 15, 1989 - Colonel General) of the Engineering Troops Kuznetsov, Vladimir Pavlovich
See also
Sapper army
Assault Engineering Brigades
References
Military units and formations of the Soviet Union
Military engineer corps
Military units and formations established in 1918
1918 establishments in Russia
Military units and formations disestablished in 1991 | Engineer Troops (Soviet Union) | [
"Engineering"
] | 1,048 | [
"Engineering units and formations",
"Military engineer corps"
] |
71,917,325 | https://en.wikipedia.org/wiki/List%20of%20Art%20Deco%20architecture%20in%20Kansas | This is a list of buildings that are examples of the Art Deco architectural style in Kansas, United States.
Abilene
203 North Buckeye, Abilene, 1930
Abilene Swimming Pool, Abilene, 1937
Garfield School, Abilene, 1942
Hotel Sunflower, Abilene, 1925
Sunflower Building, Abilene, 1931
Arkansas City
AC Office Building, Arkansas City, 1929
First Intermark (former Newman's Department Store), Arkansas City, 1917
Holt Motor Company (former Arkansas City Motor Company, R&K Motor Company), Arkansas City, 1911
El Dorado
101 Main Street, El Dorado, 1930
El Dorado Middle School, El Dorado, 1930s
USD 490 District Performing Arts Center, El Dorado, 1937
Emporia
520 North Commercial, Emporia, 1932
624 North Commercial, Emporia, 1910
701 North Commercial, Emporia, 1925
Hutchinson
Catalyst Lofts & Extended Stay, Hutchinson, 1927
Fox Theater, Hutchinson, 1931
Hutchinson Fire Station No. 1, Hutchinson, 1935
Lyons Middle School, Hutchinson, 1930
Reno County Courthouse, Hutchinson, 1930
S. H. Kress and Co. Building, Hutchinson, 1933
Strand Theatre, Hutchinson, 1913
United States Post Office, Hutchinson, 1942
Kansas City
1327, Minnesota Avenue Kansas City, 1931 and 1945
1401 Minnesota Avenue (former dairy), Kansas City, 1931 and 1945
1830 Minnesota Avenue, Kansas City, 1931 and 1945
AT&T Building, 948 North 10th Street, Kansas City, 1938
Boulevard at the Med Center Apartments, Kansas City, 1938
Kansas City Kansan Building, Kansas City, 1928
Kansas State School for the Blind, Kansas City, 1937
Kaw Valley State Bank, Kansas City
Kellogg's Snacks Plant, Kansas City
Parker School, Kansas City, 1938
Sumner Academy of Arts & Science, Kansas City, 1937
Vernon School, Kansas City, 1936
Washington High School, Kansas City, 1932
Wyandotte High School, Kansas City, 1936
Olathe
New Century AirCenter Administration Building, Olathe, 1942
New Century AirCenter Air Station Garage, Olathe, 1942
New Century AirCenter Mechanics Garage, Olathe, 1942
New Century AirCenter Power Station, Olathe, 1942
Salina
107 North Santa Fe Avenue, Salina
109–111 North Santa Fe Avenue, Salina
129 North Santa Fe Avenue, Salina
131 North Santa Fe Avenue, Salina
135 North Santa Fe Avenue, Salina
145 North Santa Fe Avenue, Salina
234 North Santa Fe Avenue, Salina
243 North Santa Fe Avenue, Salina
Cork Building (now Extraordinary Events), Salina
Fox–Watson Theater Building, Salina, 1931
Municipal Waterworks, Salina, 1934
United Building, Salina, 1930
Vogue Theatre (former Limon–Bell Tire Company), Salina, 1928
Topeka
305 Southeast 17th, Topeka, 1940
1802 Northwest Topeka Boulevard, Topeka, 1939
Agriculture Hall, Kansas State Fairgrounds, Topeka
American Legion Post 400, Topeka, 1930
Coca-Cola Bottling Company, Topeka, 1940
East Topeka Junior High School, Topeka, 1935
Iron Rail Brewing (former W.T. Grant Building), Topeka, 1935
Kansas Department of Transportation District 1 Building, Topeka, 1935
Kaw Valley State Bank, Topeka, 1935
Santa Fe Hospital, Topeka, 1930
Sumner Elementary School, Topeka, 1936
Topeka Performing Arts Center, Topeka, 1939
Topeka Water Pollution Control Waste Water Treatment Plant, Topeka, 1929
Wichita
Adeline Apartment Building, Wichita, 1923
Allen's Market, Wichita, 1930
Dunbar Theatre, Wichita, 1941
Griffin Architectural Office Building, Wichita, 1940
Helzburg Building, 219 East Douglas, Wichita, 1948
Hiland Dairy, Wichita, 1945
John Marshall Middle School, Wichita, 1939
Johnson Drug Store Building, Wichita, 1930
Johnson–Cohlmia Building, Wichita, 1930
Kansas Aviation Museum, Wichita, 1935
Kellogg Elementary School, Wichita, 1935
Longfellow Elementary School, Wichita, 1930
Marquee Motorcars, Wichita, 1930
Minisa Bridge, Wichita, 1932
North Riverside Park Comfort Station, Wichita, 1934
Petroleum Building, Wichita, 1929
Robinson Middle School, Wichita, 1931
Sedgwick County EMS County Employee Association, Wichita, 1941
Steffen Ice and Ice Cream Co. (now Hiland-Steffen Dairy Foods), Wichita, 1931
United States Post Office and Federal Building, Wichita, 1936
Walter S. Henrion House, Wichita, 1929
Wichita North High School, Wichita, 192
Other cities
American Legion Hall, Wellington, 1938
Anthony Municipal Hall, Anthony, 1935
Anthony Theater, Anthony, 1936
Augusta Theater, Augusta, 1935
Beloit Municipal Building, Beloit, 1897, 1917
Besse Apartments (former Hotel Besse), Pittsburg, 1927
Burlington Opry (former Plaza Theatre), Burlington, 1925 and 1940
Clay Center Municipal Band Shell, Clay Center, 1933
Colby City Hall, Colby, 1936
Communitea, Overland Park, 1945
Cottonwood Falls Municipal Building, Cottonwood Falls, 1938
Crest Theatre, Great Bend, 1950
Decatur Community High School, Oberlin, 1930s
Dighton High School, Dighton, 1936
Dream Theater, Russell, 1929 and 1949
Earl H. Ellis VFW Post No. 1362, Pratt, 1939
Eugene Ware Elementary School, Fort Scott, 1935
First National Bank, Herrington, 1930
Fowler Swimming Pool and Bathhouse, Fowler, 1936
Grant County Courthouse District, Ulysses, 1929
Greeley County High School, Tribune, 1941
Gregg Theatre, 116 South Chautauqua Street, Sedan, 1938
Hiawatha National Guard Armory, Hiawatha, 1938
High School Gymnasium, Elk Falls, 1920
Hollywood Theater, Leavenworth, 1937
Hoisington High School, Hoisington, 1940
Hotel Roberts, Pratt, 1930
Howard T. Sawhill City Park Bandshell, St. Francis, 1934
Ice Plant, Downtown Wellington Historic District, Wellington, 1935
Jewell County Courthouse, Mankato, 1937
Junction City Fire Department (former Municipal Building), Junction City, 1936
Labette County High School, Altamont, 1940
Lane County Community High School, Dighton, 1938
Lincoln Elementary School, Clay Center, 1939
Lincoln School, District 2, Ellwood, 1935
Marysville High School and Junior High Complex, Marysville, 1937
Masonic Hall, Hays, 1947
McDaniel Education Resource Center, Bonner Springs, 1935
McKague Memorial Masonic Temple, Oberlin, 1932
Municipal Building, Edna, 1939
NLC Elementary (former Americus High School), Americus, 1941
Nova Theatre, Stockton, 1933
Norcatur City Hall, Norcatur, 1937
Overland Theatre (former Rio Theatre), Overland Park, 1925
Paradise Water Tower, Paradise, 1938
Parsons Public Swimming Pool, Parsons, 1935
Power Plant No. 1, McPherson, 1934
Republic County Courthouse, Belleville, 1939
Ruleton School, Ruleton, 1928
St. Benedict's Abbey, Atchinson, 1957
St. Francis Community High School, St. Francis
Scott City High School, Scott City, 1930
Telephone Building, Goodland, 1931
Thomas County Insurance (former Telephone Building), Colby
United States. Post Office (former high school), Englewood, 1940
United States Post Office, Sabetha, 1937
United Telephone Building, Goodland, 1931
Wabaunsee County Courthouse, Alma, 1932
Wakefield High School, Wakefield, 1949
Warshaw Building, Dodge City, 1915 and 1930
Washington City Hall, Washington, 1934
Washington County Courthouse, Washington, 1934
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 Kansas | List of Art Deco architecture in Kansas | [
"Engineering"
] | 1,637 | [
"Architecture lists",
"Architecture"
] |
71,918,023 | https://en.wikipedia.org/wiki/Futibatinib | Futibatinib, sold under the brand name Lytgobi, is an anti-cancer medication used for the treatment of cholangiocarcinoma (bile duct cancer). It is a kinase inhibitor. It is taken by mouth.
Futibatinib was approved for medical use in the United States in September 2022, in Japan in June 2023 and in the European Union in July 2023.
Medical uses
Futibatinib is indicated for the treatment of adults with previously treated, unresectable, locally advanced or metastatic intrahepatic cholangiocarcinoma harboring fibroblast growth factor receptor 2 (FGFR2) gene fusions or other rearrangements.
Society and culture
Legal status
On 26 April 2023, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion, recommending the granting of a conditional marketing authorization for the medicinal product Lytgobi, intended for the second-line treatment of locally advanced or metastatic cholangiocarcinoma characterized by fusion or rearrangements of fibroblast growth factor receptor (FGFR) 2. The applicant for this medicinal product is Taiho Pharma Netherlands B.V. Futibatinib was approved for medical use in the European Union in July 2023.
Names
Futibatinib is the international nonproprietary name (INN).
References
Antineoplastic drugs
Pyrazolopyrimidines
Methoxy compounds
Amines
Orphan drugs | Futibatinib | [
"Chemistry"
] | 326 | [
"Pharmacology",
"Functional groups",
"Medicinal chemistry stubs",
"Amines",
"Pharmacology stubs",
"Bases (chemistry)"
] |
71,920,859 | https://en.wikipedia.org/wiki/Triphenyl%20phosphite%20ozonide | Triphenyl phosphite ozonide (TPPO) is a chemical compound with the formula PO3(C6H5O)3 that is used to generate singlet oxygen.
When TPPO is mixed with amines, the ozonide breaks down into singlet oxygen and leaves behind triphenyl phosphite. Pyridine is the only known amine that can effectively cause the breakdown of TPPO while not quenching any of the produced oxygen.
Synthesis
Triphenyl phosphite ozonide is created by bubbling dry ozone through dichloromethane with triphenyl phosphite being added dropwise at -78 °C. If triphenyl phosphite is added in excess in the synthesis, TPPO can be reduced to triphenyl phosphite oxide, PO(C6H5O)3, and oxygen gas.
References
Ozonides
Organophosphites
Phenol ethers | Triphenyl phosphite ozonide | [
"Chemistry"
] | 206 | [] |
71,921,160 | https://en.wikipedia.org/wiki/Kanta%20Subbarao | Kanta Subbarao is an Indian virologist, molecular geneticist, and physician-scientist. She is director of the World Health Organization collaborating centre for reference and research on influenza. Subbarao is also a professor at the Doherty Institute.
Life
Subbarao received a M.B.B.S. from Christian Medical College Vellore and a M.P. H. in epidemiology from the University of Oklahoma.
She is a virologist, physician-scientist, and molecular geneticist. Subbarao was convinced to join the influenza program at the National Institute of Allergy and Infectious Diseases (NIAID) when all of the positions in the respiratory syncytial virus program, which she wanted to join, were filled. She served as chief of the NIAID Emerging Respiratory Viruses Section. She is an elected fellow of the American Academy of Microbiology and the Infectious Diseases Society of America. In 2016, she joined World Health Organization collaborating centre for reference and research on influenza. She is a professor at the Doherty Institute. Subbarao became an elected fellow of the Australian Academy of Health and Medical Sciences in 2021.
References
Living people
Place of birth missing (living people)
Year of birth missing (living people)
Indian virologists
Indian geneticists
Indian women biologists
21st-century Indian medical doctors
21st-century Indian women medical doctors
Indian emigrants to Australia
National Institutes of Health people
Molecular geneticists
Women molecular biologists
21st-century Indian biologists
Fellows of the Australian Academy of Health and Medical Sciences
Women virologists
Women geneticists
Women medical researchers
Indian medical researchers
Physician-scientists
Influenza researchers
Fellows of the Infectious Diseases Society of America
Fellows of the American Academy of Microbiology
Academic staff of the University of Melbourne
World Health Organization officials
University of Oklahoma alumni | Kanta Subbarao | [
"Biology"
] | 360 | [
"Molecular geneticists",
"Molecular genetics"
] |
71,922,425 | https://en.wikipedia.org/wiki/Rexy | Rexy is the colloquial nickname for a fictional Tyrannosaurus that appears throughout the Jurassic Park franchise. She first appeared in Michael Crichton's 1990 novel Jurassic Park, and made its onscreen debut in the 1993 film adaptation, directed by Steven Spielberg. She returns in the 2015 film Jurassic World and its sequels, Jurassic World: Fallen Kingdom (2018) and Jurassic World Dominion (2022).
For the original film, special-effects artist Stan Winston created an animatronic T. rex measuring 20 feet high and 40 feet long, while Steve Williams of Industrial Light & Magic (ILM) created a CGI version for a majority of the scenes. Colin Trevorrow served as the primary writer and director of the Jurassic World trilogy. Although other T. rexes appeared in the preceding Jurassic Park sequels, Trevorrow sought to bring back the same individual from the first film. ILM again worked on the animal for each of the Jurassic World films. Effects artist Neal Scanlan also created an animatronic for Fallen Kingdom.
The films do not specify a name for the animal. "Rexy" came into common usage among fans after the release of Jurassic World, although the name had also been used previously in Crichton's novel. It has since been used in other licensed media. The name "Roberta" was also used by visual-effects artist Phil Tippett in his storyboards for the original film.
Appearances
In the Jurassic Park novel and its film adaptation, the Tyrannosaurus is among many genetically engineered dinosaurs on the fictional Isla Nublar, the site of a planned theme park and zoo. She eventually escapes its enclosure and goes on to terrorize characters throughout the story. In the film version, she also kills Donald Gennaro. At the film's end, Velociraptors corner Alan Grant, Ellie Sattler, and Lex and Tim. However, the Tyrannosaurus unexpectedly arrives and battles the raptors, inadvertently saving the humans.
In Jurassic World, the island is home to a dinosaur theme park that has operated for years, with the Tyrannosaurus as a prime attraction. The animal has a reduced role compared with the original film, appearing primarily at the end to battle the escaped Indominus rex; she succeeds with help from a Mosasaurus and a Velociraptor named Blue. Isla Nublar is abandoned by the end of the film, leaving the Tyrannosaurus and other dinosaurs to reclaim the island as their own, once again.
Jurassic World Camp Cretaceous is a television series set during and after the events of Jurassic World. The same Tyrannosaurus appears several times in the series, terrorizing a group of teenaged campers who were left stranded on Isla Nublar.
The Tyrannosaurus makes several appearances throughout Jurassic World: Fallen Kingdom, which sees the dinosaurs being relocated to California for a black market auction, before eventually killing Eli Mills and escaping into the wilderness.
In Jurassic World Dominion, the Tyrannosaurus has been pursued by the California Department of Fish and Wildlife for years before being captured and sent to live at Biosyn's sanctuary in the Dolomites. There, she battles a Giganotosaurus for superiority, eventually killing the latter. A deleted scene takes place during the Cretaceous and shows the same animals in battle during that time period, though with the Giganotosaurus prevailing; a mosquito then lands on the deceased Tyrannosaurus and sucks its blood, which would eventually be used to clone the animal in the present day. The scene is included in the film's extended edition and as part of a five-minute prologue.
Production background
Jurassic Park
Special-effects artist Stan Winston worked on the dinosaurs for the first film. His team created an animatronic T. rex that stood , weighed , and was long. At the time, it was the largest sculpture ever made by Stan Winston Studio. The studio building had to be modified for the construction of the animatronic. Jack Horner, the film's paleontological consultant, called the animatronic "the closest I've ever been to a live dinosaur". The animatronic was used in a scene set during a storm, depicting the T. rex as she breaks free from its enclosure. Shooting the scene was difficult because the foam rubber skin of the animatronic would absorb water, causing the dinosaur to shake from the extra weight. In between takes, Winston's team had to dry off the dinosaur in order to proceed with filming. Winston's team initially created a miniature sculpture of the T. rex, serving as a reference for the construction of the full-sized animatronic. Industrial Light & Magic (ILM) also scanned the miniature sculpture to create CGI shots of the animal. The T. rex roar was created by combining the sounds of a baby elephant, a tiger, and an alligator.
In the first film, the T. rex was originally supposed to be killed off. Halfway through filming, director Steven Spielberg realized that the T. rex was the star of the film and decided to have the script changed just before shooting the death scene. The changes resulted in the final ending, in which the T. rex inadvertently saves the human characters by killing a pack of velociraptors. Spielberg had the ending changed out of fear that the original ending, without the T. rex, would disappoint audiences.
Jurassic World trilogy
Although preceding Jurassic Park sequels had featured other T. rexes, Colin Trevorrow sought to bring back the same individual from the first film. Trevorrow, primary writer and director for the trilogy, said about the T. rex's return, "We took the original design and obviously, technology has changed. So, it's going to move a little bit differently, but it'll move differently because it's older. And we're giving her some scars and we're tightening her skin. So, she has that feeling of, like, an older Burt Lancaster". Motion capture was used to portray the T. rex, and a full-scale foot was created for lighting reference and to help with framing shots.
For its appearance in Fallen Kingdom, ILM sent Neal Scanlan the T. rex model previously used for Jurassic World. Using the model, Scanlan created a full-scale 3D print of the T. rex head and shoulders. The life-size T. rex animatronic, which had the ability to breathe and move its head, was controlled with joysticks. It was used for a scene where the sedated T. rex is inside a cage, while Owen Grady and Claire Dearing attempt to retrieve blood from her for a transfusion to help Blue. The beginning shots of the scene were created using only the animatronic, while the ending shots solely used CGI. The middle portion of the scene used a combination of the two methods. Trevorrow said about the dinosaur, "We've been following this same character since the beginning; she's the same T. rex that was in Jurassic Park and in Jurassic World. She is iconic—not just because she's a T. rex, but because she's this T. rex".
Speaking about Dominion, Trevorrow described the Cretaceous fight as an origin story for the T. rex "in the way we might get to do in a superhero film. The T-Rex is a superhero for me". Regarding its death to the Giganotosaurus, Trevorrow called it "such a horrifying loss for all of us who grew up with the T. rex. To build this into something that feels like a revenge picture that takes place over 65 million years was one of my favorite ideas that we had". At the end of Dominion, the T. rex encounters two other tyrannosaurs, which Trevorrow confirmed as the same duo featured in The Lost World: Jurassic Park (1997). Trevorrow said he wanted to "really make the audience want her to find peace. We want her to find a home. She feels like she has been constantly displaced, time and time again. For her to find a family and sense of belonging is what I want".
For Dominion, Trevorrow wanted to reuse the animatronic T. rex from Fallen Kingdom. However, it had already deteriorated, as is common for animatronics. Instead, the animal was portrayed entirely through CGI. Previous Jurassic World films depicted the T. rex with an emaciated physical appearance compared with the first Jurassic Park. Trevorrow sought to restore her original design for Dominion. ILM located Softimage 3D files of the original T. rex model from 1992 and compared it with their modern high-resolution model, as well as images of Winston's original maquette. Changes were made to the animal's jaw, eyes, and brow ridges. David Vickery of ILM said, "The idea was literally to restore her to her former glory," stating further that fans reacted positively to the changes: "They're like, [gasps] 'Hang on, they've changed T. rex. She looks amazing!'"
Scientific accuracy
A scene in the first film depicts the T. rex chasing a Jeep. Animator Steve Williams said he decided to "throw physics out the window and create a T. rex that moved at sixty miles per hour even though its hollow bones would have busted if it ran that fast". In the film, it is stated that the T. rex has been recorded running as fast as 32 miles per hour, although scientists believe that its actual top speed would have ranged from 12 to 25 miles per hour. In the novel and its film adaptation, it is stated that the T. rex has vision based on movement, but later studies indicate that the dinosaur had binocular vision, like a bird of prey.
The physical appearance of the T. rex in the Jurassic World films is contrary to new discoveries about the dinosaur. For consistency, the films have continued to depict the dinosaur with its wrists pointing downward at an unnatural angle, whereas the real animal had its wrists facing sideways toward each other. The Jurassic World Dominion prologue features the animal lightly covered in protofeathers.
Name
Two tyrannosaurs are featured in Crichton's novel: a juvenile and an adult. Robert Muldoon, the theme park's game warden, refers to the adult on several occasions as "Rexy". Visual-effects artist Phil Tippett had worked on the original film, and his storyboards referred to the T. rex as "Roberta". The films themselves do not specify a name for the animal. Following the release of Jurassic World, fans began referring to the individual as "Rexy". The name was later used in the 2018 novel The Evolution of Claire, and is also used by Sammy, a character in Camp Cretaceous.
Reception
Writing for Screen Rant in 2017, Tom Chapman ranked the franchise's T. rexes, including "Rexy", among its greatest characters. In 2020, Rafarl Sarmiento from Screen Rant listed the T. rex as the best dinosaur in the franchise: "The T-Rex is both awe-inspiring and horrific, but at the end of the day, it's just an animal (that actually existed) fulfilling its instinct. Yet it carries an aura of grand showmanship, something that really represents the spectacle that Jurassic Park could offer." In response to fan criticism about the T. rex being portrayed as weak in battles, Trevorrow noted that this individual would be near the end of its life during the Jurassic World films.
References
Bibliography
Jurassic Park characters
Fictional clones
Fictional dinosaurs
Fictional hybrids
Female film villains
Female literary villains
Fictional genetically engineered characters
Literary characters introduced in 1990
Film characters introduced in 1993
Characters in written science fiction
Tyrannosaurus | Rexy | [
"Biology"
] | 2,430 | [
"Fictional hybrids",
"Hybrid organisms"
] |
71,922,657 | https://en.wikipedia.org/wiki/Nova%20Puppis%201673 | Nova Puppis 1673, also known as NSV 3846, is a probable nova in the constellation Puppis. It was discovered by French astronomer Jean Richer on January 12, 1673 (and again observed on January 21) during the last year of an expedition Richer made to Cayenne, French Guiana. Richer measured its position on the sky using a mural quadrant, resulting in the most precise position available for a seventeenth-century nova that might be rediscovered by modern observers. At the time of its discovery the nova had a visual magnitude of 3, making it easily visible to the naked eye.
In 1987, German astronomer Hilmar Duerbeck published an ESO photographic survey image, marked with the position of a 20th magnitude candidate for a modern identification of Nova Puppis 1673. However subsequent spectral observations of that potential remnant of the nova showed narrow Balmer absorption lines against a blue continuum, features which are not typically seen in quiescent novae. Hence, Duerbeck's proposed identification could not be confirmed.
References
Novae
Puppis
1673 in science | Nova Puppis 1673 | [
"Astronomy"
] | 219 | [
"Novae",
"Puppis",
"Astronomical events",
"Constellations"
] |
71,925,011 | https://en.wikipedia.org/wiki/Side%20effects%20of%20radiotherapy%20on%20fertility | The side effects of radiotherapy on fertility are a growing concern to patients undergoing radiotherapy as cancer treatments. Radiotherapy is essential for certain cancer treatments and often is the first point of call for patients. Radiation can be divided into two categories: ionising radiation (IR) and non-ionising radiation (NIR). IR is more dangerous than NIR and a source of this radiation is X-rays used in medical procedures, for example in radiotherapy.
IR can have varying impacts which depend on many factors including age, irradiation field and treatment dose and duration. Where the radiotherapy is directed is important as IR to the pelvis will affect the ovary and uterus or testis. Whereas cranial irradiation will disrupt the hypothalamic-pituitary-gonadal axis (HPG-A), causing subsequent disruption of hormone secretion.
In females, IR can have long-term effects on fertility, specifically on ovarian insufficiency, pubertal arrest and subsequent infertility.
In males, the use of radiotherapy can disrupt the endocrine system leading to altered spermatogenesis and consequently a decrease in sperm count, sperm motility, sperm morphology and sperm viability.
The rapid evolution of radiotherapy technologies has had the benefit of more effective and accurate treatments with less side effects.
Impacts of radiotherapy on female fertility
Radiation therapy can have a significant impact on female fertility. The damage induced varies greatly and is determined by factors such as the age of the patient along with the dose and duration of treatment given. Estimates suggest that less than 2Gy of radiation could destroy half of a female’s immature oocytes. Female ovaries are estimated to store over 1,000,000 primordial follicles at birth which decrease in number and quality with increasing age via processes such as apoptosis. Radiation therapy greatly accelerates this decline. Permanent damage occurs with follicular atrophy and reduced follicle numbers. Consequently these changes lead to uterine dysfunction due to changes in ovarian hormone production which can result in early menopause and risk of infertility.
Hormonal disruption includes female patients experiencing decrease LH (luteinising hormone) secretion and attenuated LH surges leading to increased risk of ovarian failure. LH plays an important role in proper sexual development. Further potential endocrinopathies include hypogonadism and hyperprolactinemia. Studies now suggest that the stage of follicular development may determine how much damage is induced.
Radiation therapy has been seen to also have a direct impact on the uterus, leading to changes to its vascular supply, volume and elasticity. Necrosis, atrophy and fibrosis have also all been observed in the endometrium and myometrium. Changes such as these have significant consequences in regard to pregnancy outcomes; studies suggest cancer patients receiving radiation have a higher chance of experiencing miscarriages or having low birth weight, premature children. The likelihood of perinatal infant mortality and low birth weight are significantly related to radiation dose.
Impacts of radiotherapy on male fertility
Male fertility can be greatly impacted by radiotherapy of the reproductive system. Spermatogenesis is a process by which male sperm cells are produced. This process can take up to 70 days to complete. Some of the cells involved in this process can be damaged by the use of radiotherapy. Cells called spermatogonia are the most heavily impacted by radiotherapy. These are the cells that go on to divide to produce spermatozoa, or what are commonly known as sperm cells. Spermatogonia are the most impacted by radiotherapy because they are more radiosensitive than other types of cells such as spermatozoa. This means that the whole spermatogenic process is impacted by radiotherapy.
In addition to the damage of spermatogonia, the cells which produce a hormone called testosterone are also impaired by radiotherapy. Testosterone is the main male hormone in the body. These cells are called Leydig cells and they are found in the testes. However, Leydig cells are far more resistant to radiation than other cells in the testes and only become damaged by high levels of radiotherapy. These cells are more sensitive when the radiotherapy takes place in childhood. Damaged Leydig cells reduce the levels of testosterone in the body, which in turn increases the levels of another hormone called LH. Clinically, the monitoring of these two hormones can be indicative of Leydig cell function and health.
In combination, these two processes can lead to male fertility being compromised and can sometimes result in infertility.
Long-term effects of childhood radiotherapy on fertility
The number of childhood cancer survivors is increasing due to technological and diagnostic advancements. However as a result, there is increasing concern of the long-term effects of cancer treatments, such as radiotherapy treatment. A significant issue associated with childhood radiotherapy includes infertility.
Prepubescent males who experience radiotherapy to their testes, can result in reduced spermatogenesis. This can be through damage to the germ cells, the sertoli cells and/or Leydig cells. Both the dosage and the timing of the treatment can determine the extent of disruption to spermatogenesis. In prepubescent males, low doses (>1-3Gy) can cause short-term oligospermia or azoospermia, while higher doses (>2-3 Gy) can cause permanent azoospermia.
Moreover, testicular radiation or central nervous system (CNS) radiation in prepubertal males can affect testosterone levels and cause hypoandrogenism. Testicular radiation damages the androgen-producing Leydig cells while CNS radiation impairs the hypothalamic-pituitary-gonadal (HPG) axis, reducing gonadotropin production.
In prepubescent females, high radiation dose to the pelvic region can also have adverse side effects on fertility. Long-term effects include early onset menopause, ovarian failure and inability to complete puberty. Where pregnancy occurs in these individuals, there are high risks associated with the health of the offspring due to pregnancy complications. These include low birth weight, miscarriage and premature labour.
Prevention and treatment of infertility caused by radiotherapy
In modern medicine there are multiple options to limit the effect of cancer treatment on fertility. One of the preventative measures in females is transposition of gonadal organs further from local therapeutic agents with a success rate over 90%. Another less invasive method used for many years is lead shielding of gonadal region in both males and females as a protective measure against radiotherapy.
In prepubescent males novel techniques such as testicular tissue extraction and cryopreservation as well as in vitro maturation of spermatogonia which can then be transferred to native tissue after the treatment are being heavily researched. The most common solution is cryopreservation of sperms in post pubertal males and cryopreservation of oocytes or embryos for females with smaller age constrain compared to males who can then utilise multiple assisted reproductive techniques (ART) methods such as intrauterine insemination, IVF or ICSI as an alternative resource for preservation of fertility.
Future approach to this problem focuses on cytoprotective strategies using hormonal treatment to alter HPG-A to guard reproductive organs from radiotherapy. By disrupting the gametogenesis or decreasing the sensitivity of germ cells scientists could acquire quiescent state less susceptible to side effects of cancer treatment.
References
Radiation therapy
Fertility
Infertility
Cryopreservation | Side effects of radiotherapy on fertility | [
"Chemistry"
] | 1,586 | [
"Cryopreservation",
"Cryobiology"
] |
71,925,021 | https://en.wikipedia.org/wiki/Oocyte%20abnormalities | Oocytes are immature egg cells that develop to maturity within a follicle in the ovary. Oocyte abnormalities can occur due to several factors, including premature ovarian insufficiency (POI), other maturation abnormalities, maternal ageing, and mitochondrial abnormalities.
Causes of oocyte abnormalities
Oocyte abnormalities can be caused by a variety of genetic factors affecting different stages in meiosis. Moreover, ageing is associated with oocyte abnormalities since higher maternal age is associated with oocytes with a reduced gene expression of spindle assembly checkpoints which are important in maintaining stability in the genome. A high maternal age is associated with increased chromosome segregation errors during meiosis as well, which leads to oocyte abnormalities.
Diet appears to also potentially have an effect on oocyte quality and a better diet seems to improve fertility in that aspect. Specifically, regular intake of oral antioxidants (mixture of vitamin C and E) was shown to reduce the negative effect of ageing on oocyte quantity and quality in female mice.
Chemotherapy also has an impact on the ovary and subsequently on the oocyte and granulosa cells.
Causes of premature ovarian insufficiency
Premature ovarian insufficiency (POI) is impairment of the ovaries and how they work before the age of 40 years. It can be caused by multiple factors, one being genetic. Genes and their influence determine the initial number of the primordial follicles, impact on the rate of follicular atresia, and are impactful on the age of menopause. With the advent of more sophisticated genetic screening technologies, 20 to 25% of cases of POI appear to be of genetic origin. There are cases where the origin of the condition cannot be defined or explained, and these are called idiopathic causes. Another cause could be autoimmunity, as more than 20% of women with POI have autoimmune diseases associated with the condition, such as Grave's or Hashimoto's. Infections, such as mumps, tuberculosis and malaria can also be causes of POI.
Oocyte maturation abnormalities (OMAS)
Oocyte maturation abnormalities (OMAS) are repeatedly experienced in a small percentage of infertile women. These are problems with the maturation of oocytes; the step in oocyte development that occurs just before ovulation and successive fertilisation.
Oocytes must mature in order to reach reproductive potential. Until puberty, oocytes are kept in a dormant state in primordial follicles. At puberty the oocyte must exit its dormant stage and re-enter meiosis in order for ovulation to occur.
OMAS are usually diagnosed in women attempting in vitro fertilisation (IVF), and include premature ovarian insufficiency (POI), degenerated and dysmorphic oocytes, empty follicle syndrome (EFS), oocyte maturation arrest, and resistant ovary syndrome (ROS).
Degenerated and dysmorphic oocytes are not uncommon in assisted reproduction. Degenerated oocytes are classified as damaged oocytes or oocytes without a zona pellucida. Dysmorphic oocytes are oocytes with abnormal physical characteristics, for example multiple nuclei.
EFS is a condition occurring when no oocytes are produced from the mature follicle after ovulation is induced in cycles of in vitro fertilisation (IVF).
Oocyte maturation arrest can be sub-classified into five different types of arrest, depending on the stage of maturation they are arrested at: germinal vesicle (GV) arrest, Meiosis I (MI) arrest, Meisos II (MII) arrest, GV and MI combined arrest, and mixed arrest.
ROS is when the oocyte does not respond to normal hormone signals, and has increased levels of follicle stimulating hormone (FSH) and luteinising hormone (LH). Persevering immature oocytes are often observed in this condition.
Ageing oocytes
Maternal age and its negative effects on oocytes plays a key role in the reduction of fertility in women over 35 years of age. Ageing predominantly affects oocytes during their arrest in the prophase of meiosis I – where genetic stability is often undermined.
The principal oocyte abnormality associated with increased maternal age is aneuploidy, in which chromosome segregation errors result in oocytes having the wrong number of chromosomes.
Causes for these errors are not fully understood however, some proposed mechanisms include:
Oxidative stress, the impact of which is due to aging’s connection with increased levels of reactive oxygen species (ROS). When left unchecked this can result in follicular atresia and reduction in both the number and quality of oocytes.
Spindle assembly checkpoint malfunction causing gene imbalances that often result in the fertilised oocyte produced being incapable of developing further.
Cohesion loss due to a decrease in REC8-cohesin complex, which would normally maintain the integrity of paired chromosomes (bivalents).
DNA damage (especially involving radiation or chemotherapy) which results in oocyte elimination if picked up by the body.
Mitochondria abnormalities
Normal function of mitochondria is to generate energy through oxidative phosphorylation. During oocyte maturation and fertilization mitochondria elongate, develop cristae and the matrix changes from a dense solution to a lighter matrix. Any abnormalities in this mitochondria development can lead to chromosomal segment disorders, oocyte maturation failures and arrested cell division.
After mitochondria has fully completed conformational changes, the mitochondria DNA copy number (mtDNA) increases rapidly to support the oocyte into the blastocyst stage. Therefore a higher mtDNA number is associated with better oocyte quality and potential of fertility. There are several factors that effect mitochondria quality. These are listed below:
Age
Mitochondria appear more swollen and present disrupted cristae with increased age. They have also been found to have lower mtDNA, increased reactive oxidative species and expression of Bax which upregulates apoptosis of follicles and early embryo arrest.
Obesity
Causes delayed maturation of oocytes whereby mitochondria display fewer and disarrayed cristae. The intracellular matrix has a lower electron density and increased swelling.
Both of these factors lead to an increased chance of miscarriage due to failure to implant into the uterine lining.
Nondisjunction
Normally oocytes stay arrested at prophase of meiosis I. A surge in luteinising hormone triggers ovulation of the oocyte and triggers the resumption of meiosis. The germinal vesicle breaks down and spindles assemble as homologous chromosomes align the cell's equator for the first meiotic chromosome segregation. Here the oocyte splits where sister chromatids migrate to the same pole and the first polar body is formed. The oocyte now enters meiosis II and remains arrested in metaphase II until fertilization where sister chromatids will separate.
During this process at least one crossover per homologous pair is required for successful chromosome segregation. If this does not occur it can result in nondisjunction and aneuploidy. There are several factors that contribute towards failed crossovers including:
Lack of cohesion along the chromosome arms means the chiasmata cannot be secured properly.
Failed chiasmata maintenance. Crossovers that occur towards the end of the telomere can slide off the end of the homologous chromosomes leading to premature separation of the homologs causing defective chromosome configurations.
Missegregation of sister chromatids during Metaphase II.
Age dependent weakening of sister chromatid cohesion.
References
Germ cells
Reproductive system | Oocyte abnormalities | [
"Biology"
] | 1,661 | [
"Behavior",
"Reproductive system",
"Sex",
"Reproduction",
"Organ systems"
] |
71,925,028 | https://en.wikipedia.org/wiki/Germ%20cell%20nest | The germ cell nest (germ-line cyst) forms in the ovaries during their development. The nest consists of multiple interconnected oogonia formed by incomplete cell division. The interconnected oogonia are surrounded by somatic cells called granulosa cells. Later on in development, the germ cell nests break down through invasion of granulosa cells. The result is individual oogonia surrounded by a single layer of granulosa cells. There is also a comparative germ cell nest structure in the developing spermatogonia, with interconnected intracellular cytoplasmic bridges.
Formation of germ cell nests
Prior to meiosis primordial germ cells (PGCs) migrate to the gonads and mitotically divide along the genital ridge in clusters or nests of cells referred to as germline cysts or germ cell nests. The understating of germ cell nest formation is limited. However, invertebrate models, especially drosophila have provided insight into the mechanisms surrounding formation. In females, it is suggested that cysts form from dividing progenitor cells. During this cyst formation, 4 rounds of division with incomplete cytokinesis occur resulting in cystocytes that are joined by intercellular bridges, also known as ring canals.
Rodent PGCs migrate to the gonads and mitotically divide at embryonic day (E) 10.5. It is at this stage they switch from complete to incomplete cytokinesis during the mitotic cycle from E10.5-E14.5. Germ cell nests emerge following consecutive divisions of progenitor cells resulting from cleavage furrows arresting and forming intercellular bridges. The intercellular bridges are crucial in maintaining effective communication. They ensure meiosis begins immediately after the mitotic cyst formation cycle is complete. In females, mitosis will end at E14.5 and meiosis will commence. However, It is possible that germ cells may travel to the gonads and cluster together forming nests after their arrival or form through cellular aggregation.
Function
Most of our understanding of germ cell nests come from Drosophila (fruit flies). In the Drosophila model, germ cell nests arise from incomplete cell division (cytokinesis), forming bridges between the daughter cells called ring canals. In ovarian cysts, generally all but one cell differentiate into nurse cells and transport materials through these ring canals to accelerate the growth of the remaining cell, which becomes the oocyte (egg cell). In males, sperm cells almost all develop in these clusters of germ cells, and they are thought to benefit from the interconnection between them because the genetic materials are shared between them through the ring canals, which reduces the production of non-functional sperm and the selection for certain genotypes over others (meiotic drive). There is also a high level of synchronisation between the clustered germ cells in males. In females, germ cell nests enable large eggs to be produced through the support of differentiated cystocytes into nurse cells. Supporting the oocyte with nurse cells within the germ cell nest also means that the oocyte nucleus can stay inactive, which reduces its susceptibility to mutations and parasites (largely applies to insect models). However, there doesn’t seem to be much synchrony despite the presence of ring canals. Transport through ring canals is highly regulated and directional in the ovarian germ-line cysts.
Similar to the drosophila model, germ-line cysts in mammals such as mice and humans facilitate the transport of substances through the microtubules between nuclei within the syncytia. Organelles including the smooth ER, ribosomes, smooth vesicles, mitochondria and microtubules can be found within the ring canal in mouse, rabbit and human foetal ovaries. This allows organelles redistribution during oocyte differentiation, leading to about 20% of the foetal germ cells differentiating into primary oocytes with enriched cytoplasmic content. The germ cells that donate their cytoplasm undergo apoptosis. Besides this function, it has been proposed that germ-line cysts may also facilitate the onset of meiosis, facilitate organelle biogenesis through enriching mitochondria, inhibit mitosis to restrict the number of germ cells entering meiosis, and restrict the motility of germ cells.
Breakdown
In the mouse, germ cell nest breakdown occurs just after birth, and in humans, this breakdown occurs during the second trimester of gestation. Germ cell nest breakdown involves the degeneration of many germ cell nuclei and the invasion of pre-granulosa cells into the nests. In the germ cell nest, one germ cell matures into an oocyte whereas others act as ‘nurse cells’, transferring their contents including cytoplasmic organelles like mitochondria into the predestined oocyte. These nurse cells subsequently undergo apoptosis.
Cytoplasmic bridges between the remaining nuclei are cleaved through protease action of the surrounding somatic cells. Once the granulosa cells have fully surrounded the remaining nuclei, a basement membrane is laid down and completely encompasses each newly formed primordial follicle. The reason for selective loss of germ cells during nest breakdown has been suggested to be due to genetic defects or failure of the germ cell to produce the necessary cytoplasmic organelles, therefore acting as a quality control mechanism.
Female vs. male gametogenesis
In males, this process of spermatogenesis is slightly different to that of female oogenesis but does have a comparative ‘germ-line nest/cyst’. Male germ-line stem cells divide asymmetrically to give one stem cell and a spermatogonia cell (unspecialised male germ cell) that undergoes mitotic proliferation to form primary spermatocytes (diploid - 46 chromosomes in the human). Each spermatocyte undergoes two rounds of meiosis to produce in the first round, two haploid secondary spermatocytes, and in the second round into four haploid (23 chromosomes in the human) spermatids. These spermatids then undergo differentiation into mature sperm.
In these developing male germ cells, they undergo incomplete cytokinesis during the mitosis and meiosis. Cytokinesis is normally when the cytoplasm of one parent cell divides to split into two daughter cells. Large clones of differentiating (specialising) daughter cells that have descended from one maturing spermatogonia (undifferentiated, immature male germ cell) remain connected by stable intracellular cytoplasmic bridges that interconnect the cells. This forms a syncytium – this is a mass of cytoplasm containing many nuclei enclosed within one plasma membrane. These persist until the end of sperm differentiation when individual sperm are released into the seminiferous tubule lumen. The seminiferous tubules are the functional unit of the testis, and contain germ cells at various stages of maturation, and many other constituents.
These intra-cellular bridges promote germ cell communication and sharing of cytoplasmic constituents, and allow for synchronisation of mitotic divisions and entry into meiosis. They are required for fertility in male insects and mammals. In mammals, germ cells form syncytia of hundreds of germ cells interconnected by intercellular bridges. As they share a common cytoplasm with their neighbours, cells can be supplied with all the products of a complete diploid genome. Developing sperm carrying a Y chromosome can be supplied with essential proteins encoded by genes on the X chromosome.
References
Germ cells
Reproductive system | Germ cell nest | [
"Biology"
] | 1,611 | [
"Behavior",
"Reproductive system",
"Sex",
"Reproduction",
"Organ systems"
] |
71,925,191 | https://en.wikipedia.org/wiki/Neohormone | Neohormones are a group of recently evolved hormones primarily associated to the success of mammalian development. These hormones are specific to mammals and are not found in other vertebrates—this is because neohormones are evolved to enhance specific mammalian functions. In males, neohormones play important roles in regulating testicular descent (the testes descend into the scrotum during foetal development) and preparing the sperm for internal fertilisation (the sperm fertilizes the egg within the female). In females, neohormones are essential for regulating early pregnancy, mammary gland development lactation (secretion of milk from the mammary gland), and viviparity (allowing the fertilized egg to grow inside the female until they can exist independently). Neohormones superimpose their actions on the hypothalamic-pituitary-gonadal axis (a hormone system which regulates key reproductive functions in animals) and are not associated with other core bodily functions.
Pre-natal functions of neohormones
Prenatally, neohormones play a role in the development of the embryo as well as supporting early pregnancy.
H2 Relaxin
In the human ovary, H2 relaxin is produced by the corpus luteum and by Granulosa cells from large antral follicles. Research has shown that the relaxin gene is expressed once the Granulosa cells have reached a certain luteinised status, by which Granulosa cells differentiate into Luteal cells. Therefore, it can act as a good biomarker in relation to Granulosa cell differentiation status.
Relaxin is produced to support early pregnancy until the placenta can take over. Relaxin plays a key role in implantation and placenta formation.
The relaxin receptor RXFP1 is found on myometrial cells. In rats, it has been linked playing a role in the spacing between embryos in the uterus. RXFP1 is also located on endometrial stromal cells where it can induce cyclic adenosine monophosphate (cAMP). cAMP is a molecule which is necessary for the functional changes in the endometrium to form the decidual lining, where the blastocyst can implant. This results in neo-angiogenesis and endometrial thickening, both linked to early pregnancy development.
Human chorionic gonadotropin
Human chorionic gonadotropin (hCG) is a hormone produced by the placenta during pregnancy. This hormone stimulates the Corpus Luteum to produce progesterone to maintain pregnancy. Therefore, hCG plays a role in human maternal recognition of pregnancy.
Insulin-like peptide 3
Insulin-Like Peptide 3 (INSL3) is produced by the interstitial Leydig cells located in the adult testes. Leydig cells are responsible for steroidogenesis, the fetal Leydig cells differentiate during the development of the embryo. They produce necessary androgens for the masculinisation of organs. They also produce INSL3, which is required for the first transabdominal phase of testicular descent. INSL3 acts on RXFP2 receptors which link the testis to the inguinal abdominal wall. As a result, the testes move from the inguinal canal into the scrotum. Only mammals have a scrotum and descended testes. INSL3 measured in amniotic fluid can therefore be a biomarker for testis development, although this period differs between species.
Post-natal functions of neohormones
After birth, neohormones play a major role in development of mammary glands and their function. Alongside, neohormones have also been measured to be a significant component of breast milk. The so-called lactocrine hypothesis dictates that breast milk does not simply fulfil nutritional requirements but also plays an important role in signaling and development in the neonate. Neohormones are theorised to have specific effects on target organs in the neonate, but more research is needed in this area, and effects have been observed to different extents in different species.
Oxytocin
Oxytocin is responsible for the milk let-down reflex as a response to neonate suckling. It is released from the posterior pituitary gland in a pulsatile manner, via stimulation of the vagus nerve. This causes myoepithelial cells, which surround the mammary alveoli, to contract. Oxytocin injections have been found to increase milk yield in cows. The role of oxytocin in the neonate is yet quite unclear, however we know that oxytocin has an important role in empathy and bonding between pairs.
Relaxin
There are three relaxin genes in humans. One type, H2, is made and secreted in the ovaries, as well as in the mammary glands. Relaxin acts via locally expressed specific receptors located on parenchyma and myoepithelial cells. It reaches peak concentrations 24-48 hours after birth and then declines.
Human Chorionic Gonadotropin
Like relaxin, hCG may be measured, although the effects on the neonate are not well understood. It is posited that it may act as an LH paralogue to affect the development of neonatal gonads, although further research is required.
Biomarkers of reproductive health
The main neohormones that can be used as biomarkers of reproductive health are relaxin, oxytocin, hCG, INSL3, and INSL5 and INSL6.
Relaxin (Specifically Ovarian H2-relaxin) aids in the implantation of the embryo into the uterine wall after fertilisation, as well as establishing the placenta. The levels of relaxin are altered in cases of early miscarriage and hence can be used as a biomarker during early pregnancy.
Oxytocin has a range of functions in the reproductive systems of both males and females. It has a major role in the production of breast milk and lactation. It is responsible for muscle contractions in the uterus to facilitate birth. It also assists in ovarian steroid production and ovum release. In men, oxytocin has a role in erections and ejaculation. It also participates in gonadal development in both males and females. Despite being tricky to measure, measuring oxytocin can help build a clinical picture of reproductive health in the above mechanisms.
hCG has a vital role in early pregnancy. Higher levels of hCG is a good indication for the survival and viability of the embryo. β-hCG can be monitored to test for an ectopic pregnancy.
INSL3 is responsible for the first phase of testicular descent in males and may be disrupted in cases of cryptorchidism. It also acts as a measure of Leydig cell function, particularly in older males.
INSL5 and INSL6 may have a role in spermatogenesis. There are currently no ways to measure these hormones but there is some evidence that with altered INSL5, there is reduced fertility and impaired spermatogenesis.
Therapeutic uses of neohormones
Relaxin has been shown to repair and reverse the symptoms associated with scleroderma (an autoimmune condition affecting connective tissues, blood vessels and internal organs) and fibrosis (thickening, hardening or build up of scar tissue). It also aids in the formation of new blood vessels (angiogenesis). This is also beneficial in wound management and healing. Other potential targets include the use of relaxin within human reproduction, such as in the preparation of the cervix for labour and birth and also as a drug target for breast cancer treatment although much more research is required in this area.
Oxytocin is important for many different biological processes including social, maternal and sexual behaviours, pregnancy, milk production, and ejaculation. Agonists and antagonists of oxytocin – development of drugs that can utilise the receptor binding activity of oxytocin is an important therapeutic target as this could be applied to a range of conditions. Oxytocin plays a role in cell proliferation and differentiation in different ways depending on where it is in the body. Understanding the underlying pathways for different localities could help with development of cancer therapies.
References
Hormones
Endocrine system
Mammalian hormones | Neohormone | [
"Biology"
] | 1,770 | [
"Organ systems",
"Endocrine system"
] |
71,925,526 | https://en.wikipedia.org/wiki/Sugar%20preference | Sugar preference is a biological phenomena where sugar is favored over artificial sweeteners by both humans and animals.
Neurological process
All animals need sugar as their primary source of energy, hence the majority of species have developed specific neural circuits to look for, recognize, and encourage their use of it.
As originally shown by Ivan De Araujo, animals who lack sweet taste receptors can still develop strong preferences for sugar, indicating a process unrelated to taste.The neurological underpinnings of sugar preference showed that the gut-brain axis activates a population of neurons in the brainstem and superior ganglion of vagus nerve to produce a desire for sugar. Direct sugar supply to the gut activates these neurons, which are stimulated by sugar but not by artificial sweeteners .
Specific taste receptor cells on the tongue and palate epithelium are able to detect sweet substances. Hardwired signals are sent to the brain by activated sweet taste receptor cells to trigger detection of sweet-tasting compounds. Researchers have investigated the circuits that link the activation of sweet taste receptors on the tongue to the attraction that is elicited by sweetness. Remarkably, animals can still develop a desire for sugar even in the absence of a functional sweet-taste pathway. In addition, although activating the same sweet taste receptor as sugars and possibly doing so with far higher affinities , artificial sweeteners are unable to replace sugar in terms of eliciting a behavioral preference.
Taste buds
Shortly after the sweet taste receptor was discovered, researchers attempted to remove those taste buds . But scientists discovered that an animal who lacks taste receptors could nevertheless distinguish between natural sugar and artificial sweeteners and preferred the latter.
When offered the option to choose between water and sugar, the animal virtually always chooses the sugar solution. However, when given the option to choose between sugar and an artificial sweetener (such as Acesulfame potassium ) at concentrations where both are equally desirable, it initially consumes the contents of both bottles at a similar pace. However, after being exposed to both options for 24 hours, its preference significantly changes, and after 48 hours, they nearly exclusively drink from the sugar-containing bottle. This behavioral change also occurs in the animal without the ability to taste sweet things. Thus, despite the fact that they are unable to taste sugar or sweetener, it is nevertheless able to identify and select sugar, most likely as a result of the sugar's post-ingestive effects .
Caloric sugars and non-caloric sweeteners
Caloric sugars are preferred by animals over non-caloric sweets by nature. The amount of sugar that enters the intestines determines this predilection. Although the brain becomes aware of the stimulation in a few seconds, it is unknown how the gut determines the caloric sugar to influence choice. A new cell was identified - a neuropod, an intestinal transducer. This cell synapses with the vagus to instantly alert the brain to the presence of glucose in the gut. The electrogenic sodium glucose co-transporter 1 (Sodium-glucose transport proteins SGLT1) or sweet taste receptors are used by neuropod cells to differentiate between a caloric sugar and a non-caloric sweetener. Adenosine triphosphate (ATP) is released when non-caloric sucralose activates neuropod cells, but glutamate is released when caloric sucrose enters through SGLT1.
A technique was created in order to record animal preferences in real time while utilizing optogenetics to quiet or excite neuropod cells in order to examine the role of the neuropod cell in sugar preference. It was found that mice cannot detect the caloric sugar when these cells are silenced or their glutamatergic transmission is blocked. Additionally, stimulating neuropod cells causes the animal to take the calorie-free sweetener as if it was a calorie. Neuropod cells direct an animal's internal predilection toward the caloric sugar by translating the particular identification of the stimuli entering the stomach
References
Bibliography
Miller, N. E. & Kessen, M. L. Reward effects of food via stomach fistula compared with those of food via mouth. J. Comp. Physiol. Psychol. 45, 555–564 (1952).
Sclafani, A. Post-ingestive positive controls of ingestive behavior. Appetite 36, 79–83 (2001)
de Araujo, I. E. et al. Food Reward in the Absence of Taste Receptor Signaling. Neuron (2008) doi: 10.1016/j.neuron.2008.01.032
Han, W. et al. Striatal Dopamine Links Gastrointestinal Rerouting to Altered Sweet Appetite. Cell Metab. 23, 103–112 (2016)
Bohórquez, D. V. et al. Neuroepithelial circuit formed by innervation of sensory enteroendocrine cells. J. Clin. Invest. 125, 782–786 (2015)
Williams, E. K. K. et al. Sensory Neurons that Detect Stretch and Nutrients in the Digestive System. Cell (2016) doi: 10.1016/j.cell.2016.05.011.
Su, Z., Alhadeff, A. L. & Betley, J. N. Nutritive, Post-ingestive Signals Are the Primary Regulators of AgRP Neuron Activity. Cell Rep. (2017) doi: 10.1016/j.celrep.2017.11.036.
Beutler, L. R. et al. Dynamics of Gut-Brain Communication Underlying Hunger. Neuron (2017) doi: 10.1016/j.neuron.2017.09.043.
Bohórquez, D. V. et al. Neuroepithelial circuit formed by innervation of sensory enteroendocrine cells. J. Clin. Invest. 125, (2015)
Kaelberer, M. M. et al. A gut-brain neural circuit for nutrient sensory transduction. Science (80-.). (2018) doi: 10.1126/science.aat5236.
External links
bioRxiv: A gut sensor for sugar preference
Nature Journal: The gut – brain axis mediates sugar preference
Neurology
Preference
Gustatory system | Sugar preference | [
"Chemistry"
] | 1,325 | [
"Carbohydrates",
"Sugar"
] |
71,925,757 | https://en.wikipedia.org/wiki/2021%20North-East%20England%20shellfish%20die-off | The 2021 North-East England shellfish die-off was a series of occasions where a mass of shellfish were found on beaches on the Durham and Yorkshire Coasts in northern England, either dead, or in stages of dying.
These events first occurred in October 2021, with re-occurrences in February, and September 2022, with concerns being raised at the amount of crabs, lobsters and other marine animals found dead. An initial investigation by the Department for Environment, Food and Rural Affairs (Defra) stated a large algal bloom had killed off the marine life. However, those working in the fishing industry and independent scientists, claimed the deaths was caused by pyridine poisoning, an effect of dredging in the River Tees.
A second government investigation, published in January 2023, stated neither an algal bloom or pyridine poisoning could explain the deaths over such a long period of time, wide area and the unusual twitching in crabs. The scientists concluded that a disease, "novel pathogen" was the "most likely cause of the mortality."
Initial occurrence
In October 2021 thousands of dead crabs and lobsters were washed up on the Tees estuary and beaches along the North-East coast of England. The deaths were first reported in Seaton Carew, Redcar and Seaham. A 95% decline in the lobster and crab catch was noticed by those employed in the local fishing industry. A spokesperson for the Environment Agency said, "Samples of water, sediment, mussel and crab have been collected and are being sent to our labs for analysis to consider whether a pollution incident could have contributed to the deaths of the animals." The Centre for Environment, Fisheries and Aquaculture Science (Cefas) labs were also testing crustaceans for signs of disease. At the time of the initial waves of deaths, the Environment Agency stated that "there is no evidence of any link to recent strandings of marine mammals and seabirds across the UK and counties along the North Sea coast."
One theory that a new interconnector cable from Northumberland to Norway was responsible was rejected by the National Grid, saying the cables were 'well buried in the seabed, made of steel and unlikely to be broken by wildlife.' The electro-magnetic field given off by underwater power cables has been found to mesmerise brown crabs and cause biological changes, such as changes to the number of blood cells in the crabs’ bodies. However, in November 2021, sewage, seismic activity, and underwater cables were ruled out as a cause of the deaths by the Environment Agency.
Deaths of other marine creatures have been reported; a dead porpoise was photographed washed up on the beach at South Gare, close to the mouth of the Tees. Dead dogfish and sole have also been washed up. The public was advised to avoid areas of beach and coastline and to keep pets away from dead crustaceans. The Environment Agency, the Centre for Environment, Fisheries and Aquaculture Science, North Eastern Inshore Fisheries and Conservation Authority, the Marine Management Organisation, Hartlepool Borough Council and Redcar and Cleveland Borough Council, were all involved in the investigation of the cause of the incidents. By late November the crustacean die-off had spread as far south as Robin Hood's Bay and was affecting catches in Whitby. Some of the crabs and lobsters which had washed up on the beaches were in various states of dying, with "twitching and lethargic" behaviour reported.
By January 2022 over 150 dogs had suffered vomiting and diarrhoea after they visited beaches in North Yorkshire. Dogs walked on beaches at Bridlington, Whitby, Robin Hood's Bay, South Gare near Redcar, and Scarborough had been affected. The Small Animal Veterinary Surveillance Network (SAVSNET) put forward the theory that the dogs might have contracted the Canine Enteric Coronavirus. A cluster of cases have been found inland at Leeds and Kirklees. Alan Radford, a Professor of Veterinary Health Informatics at the University of Liverpool, said, "Analysis of real-time data collected by SAVSNET from veterinary practices suggests that in Yorkshire, levels of disease have been statistically higher than we would expect for three weeks – we can therefore call this an outbreak in Yorkshire." The Department for Environment Food & Rural Affairs (Defra) said, "We are not aware of any link with the issue of crustaceans washed ashore in the area late last year [and domestic pets]."
Investigations
The Environment Agency has ruled out chemical pollution as the cause of the mass shellfish deaths. Dredging was also rejected as the cause of the environmental disaster. Environment Agency operations manager Sarah Jennings said, "We've used both traditional and innovative screening methods to analyse samples of water, sediment and crab looking for traces of contamination. We’ve screened for over 1,000 potential chemical contaminants but found no anomalies that could lead to an event of this scale." The South Tees Development Corporation, who are responsible for the dredging of the Tees, stated that "we continue to follow all legal standards and requirements as is required, including the issued licence and guidance from DEFRA and MMO, who continue to rule out dredging as a likely cause."
Whilst official direction was that dredging was not the cause of the die-off, many fishermen state that they believe this to be the root cause. Defra, which started an investigation in December 2021, stated the die-off was the result of an algal bloom, however, some academics have raised the dredging issue as the shellfish had high levels of pyridine. The North East Fishing Collective (NEFC) crowdfunded a £30,000 study conducted by researchers at Newcastle, Durham, Hull and York universities, who concluded that the levels of pyridine resulted in the mass deaths. "Although it is yet to be peer reviewed, the study's early report said tests found pyridine, which is used as an anti-corrosion treatment in marine infrastructure, was "highly toxic" to crabs "even at low levels" and caused twitching and paralysis before death similar to witness reports made at the time of the mass wash-ups." Defra rejected the claim about pyridine poisoning, stating that pyridine was present in healthy crabs studied during the same period off the coast of Cornwall. They also stated that there was no link between the die-off and any dead seals on the North-East coast.
In early February 2022 it was reported that, "Defra and partner agencies have completed a thorough investigation of the cause of dead crabs and lobsters which were found washed up on the North East coast between October and December 2021. Following significant testing and modelling to rule out possible causes, Defra and partner agencies consider that the deaths of the crabs and lobsters potentially resulted from a naturally occurring harmful algal bloom." In June 2022 George Monbiot wrote in The Guardian, "Astonishingly, although there is no evidence that it conducted such sampling, the government concluded not only that a bloom had occurred, but that it was caused by a particular, toxic species: Karenia mikimotoi. This is the stuff of science fiction. Karenia thrives in temperatures between . The average water temperature on this coast in October is . There is no plausible mechanism by which a Karenia bloom could cause the mass death of lobsters and crabs without also killing large numbers of fish, sea urchins and many other species." Monbiot reported that when he asked the UK government to publish its evidence the government refused.
Tim Deere-Jones, a pollution researcher and consultant for over 30 years, was asked to investigate the incidents by Whitby Fishermen's Association. A Freedom of Information request to the Department for Environment Food & Rural Affairs revealed some crab samples were found to have concentrations of the chemical pyridine 70 times over the expected level. Deere-Jones said, "The Environment Agency must have analysed for several hundred different chemicals, most of which were there in .0-something quantities, some of which were in quantities up to the tens, but what really stood out was pyridine, which was present up to 450-plus. Apart from being astonished that nobody picked up that this one chemical was there in such quantities, I was astonished that nobody suggested that there be further work." Marine infrastructure which sits in the water is treated with pyridine to reduce corrosion, and the chemical is also released as an industrial waste product. One crab sample from Saltburn was found to contain 439mg per kg of pyridine, and 203mg per kg was found in a sample tested from Seaton. A control sample from Cornwall showed levels of 5.9mg per kg. Deere-Jones challenged the Defra conclusion, saying, "There was marine algae out there but it wasn't really what you'd call a bloom, and nobody took any samples to prove it was a lethal algal bloom."
December 2022 investigation
Another government investigation was instigated in November 2022, and was supposed to deliver its findings a month later, but it was not released to the public until January 2023. The terms of reference for the investigation, and the names of the scientists involved was deliberately kept secret to avoid pressure being put on the scientists and to enable them to complete the review free from "lobbying...in what has become an increasingly bitter debate." The report was released on 20 January 2023, and came to no definitive conclusion. The report stated that neither an algal bloom or pyridine poisoning could "..explain the deaths over such a long period of time and wide area of coastline, the unusual twitching observed by crabs or why only crustaceans and not a greater number of species had suffered the effects." The scientists raised the possibility of a new parasite or disease as the likely source of the deaths, but there were no signs of this, labelling a "novel pathogen" as the "most likely cause of the mortality."
Further occurrences
More crabs were washed up on beaches in the North-East of England during February 2022.
Concerns were raised again in September 2022, after local people at Markse and Saltburn identified another swathe of shellfish being washed up on the beach. However, the Environment Agency countered that it was "a regular occurrence at this time of year."
Aftermath
The mass die-off had a detrimental effect on the shellfish ports of Yorkshire (Bridlington, Scarborough and Whitby), and so the Whitby Lobster Hatchery had forwarded a plan to put thousands of juvenile lobsters into the North Sea. Even so, one of the marine biologists at the hatchery warned that it would "take years" for the stocks to recover.
In early October 2022, Hundreds of protestors linked arms across Saltburn beach. The protestors were part of the campaign group Reclaim the Seas, who wanted the dredging of the Tees Estuary to stop. As a result of the NEFIC report, which blamed the mass die-off on pyridine poisoning, a Parliamentary committee meeting was announced for 25 October 2022, to investigate the claims. The committee heard that those who work in the fishing industry around the Tees and the County Durham and North Yorkshire coasts, were "terrified [of the] dredging going ahead", with one stating that they were experiencing an "extinction episode". The committee heard from the secretary of Whitby Commercial Fishing Association, who stated that the lobster catch was down 50%, undersized and pregnant lobsters were down 75%, and brown crabs were down 100%.
In November 2022, the Scarborough MP, Robert Goodwill, recommended setting up a fund to provide financial support to communities affected by the shellfish die-off.
References
External links
Webpage from Newcastle University showing the effects of a pyridine bloom centred around the River Tees
BBC programme entitled Trouble at Sea
Defra report from May 2022
NEFIC independent report
Biological oceanography
Aquatic ecology
Fishing industry
Human impact on the environment
Algal blooms
Fisheries science
Yorkshire coast | 2021 North-East England shellfish die-off | [
"Chemistry",
"Biology",
"Environmental_science"
] | 2,493 | [
"Algae",
"Water treatment",
"Water pollution",
"Water quality indicators",
"Ecosystems",
"Aquatic ecology",
"Algal blooms"
] |
71,926,785 | https://en.wikipedia.org/wiki/DM%20Ursae%20Majoris | DM Ursae Majoris is a binary star system in the northern circumpolar constellation of Ursa Major, abbreviated DM UMa. It is sometimes identified by the Bonner Durchmusterung catalogue designation ; DM UMa is the variable star designation. The system has a combined apparent visual magnitude of 9.29, which is too faint to be visible to the naked eye. Based on parallax measurements, the system is located at a distance of approximately 606 light years from the Sun, but it is drifting closer with a heliocentric radial velocity of −7 km/s.
In 1978, the X-ray source designated 2A 1052+606 was initially included in the 2A catalogue of observations by the Ariel 5 satellite. The approximate position of this source was determined using the HEAO-1 satellite, then W. Liller matched it with the candidate star SAO 015338 (later DM UMa). He determined the spectra matches a K-type star with strong H-alpha emission lines. In 1979, this object was shown to be an RS Canum Venaticorum variable (RS CVn) by D. Crampton and associates, which indicated this is a close binary star system where one of the components has an active chromosphere with star spots. DM UMa was the first RS CVn variable to be so classified based on its X-ray emission.
Radial velocity measurements demonstrated an orbital period of about 7.5 days. A mass function of suggested the system is being viewed from a low inclination, close to pole-on. The system showed variations in emission lines on a time scale of a day. A photometric light curve was generated by R. A. Kimble and associates in 1981, showing strong variability within each orbital period. A model fit to the light curve indicated the star has an extensive distribution of star spots, with regions of enhanced spot activity toward and away from the companion. It is one of the few variables of this class that show a continual emission of H-alpha, although this varies by a factor of three over the course of an orbit.
This is a single-lined spectroscopic binary with the spectra matching a stellar classification of K0III-IV. The secondary is at least 1.5 magnitudes fainter than the primary, so the contribution of the former to the luminosity is no more than 20%. The observed properties of the system can be modeled by a combination of a subgiant primary of class K0IV with a K5V main sequence secondary.
References
Further reading
K-type main-sequence stars
K-type subgiants
RS Canum Venaticorum variables
Astronomical X-ray sources
Ursa Major
BD +61 1211
053425
Ursae Majoris, DM | DM Ursae Majoris | [
"Astronomy"
] | 575 | [
"Astronomical X-ray sources",
"Ursa Major",
"Astronomical objects",
"Constellations"
] |
71,928,273 | https://en.wikipedia.org/wiki/Temporal%20plasticity | Temporal plasticity, also known as fine-grained environmental adaptation, is a type of phenotypic plasticity that involves the phenotypic change of organisms in response to changes in the environment over time. Animals can respond to short-term environmental changes with physiological (reversible) and behavioral changes; plants, which are sedentary, respond to short-term environmental changes with both physiological and developmental (non-reversible) changes.
Temporal plasticity takes place over a time scale of minutes, days, or seasons, and in environments that are both variable and predictable within the lifespan of an individual. Temporal plasticity is considered adaptive if the phenotypic response results in increased fitness. Non-reversible phenotypic changes can be observed in metameric organisms such as plants that depend on the environmental condition(s) each metamer was developed under. Under some circumstances early exposure to specific stressors can affect how an individual plant is capable of responding to future environmental changes (Metaplasticity).
Reversible plasticity
A reversible change is defined as one that is expressed in response to an environmental stressor but returns to a normal state after the stress is no longer present. Reversible changes are more likely to be adaptive for an organism when the stress driving the change is temporary and the organism is likely to be exposed to it again within its lifetime. Reversible plasticity often involves changes in physiology or behavior. Perennial plants, which often experience recurring stresses in their environment due to lack of mobility, benefit greatly from reversible physiological plasticity such as changes in resource uptake and allocation. When essential nutrients are low, root and leaf resorption rates can increase, persisting at a high rate until there are more nutrients available in the soil and resorption rates can return to their normal state.
Irreversible plasticity
Irreversible changes are described as changes that remain expressed in an organism after the environmental stress has ceased. Environmental shifts that drive irreversible plasticity in an organism tend to be less rapidly changing, such as gradually increasing temperatures. This often leads to permanent changes in morphology or in the developmental process of an organism (developmental plasticity). Plants are highly plastic and tend to express many irreversible developmental changes, such as shifts in timing of bud and flower development. In animals, many organisms benefit from having multiple persisting morphs in a population that arise during development in response to environmental conditions. For example, freshwater snails will form more spherical shells when in the presence of a predator (bluegill sunfish) and conical shells when predators are absent. These shell shapes are permanent and cannot be reverted, even if the predator status of the snail's environment changes.
Examples
Morphologically and developmentally plastic traits can be reversible in some cases, and there are some physiological responses which can be irreversible, which differs from the typical trend. One example of developmental plasticity that is reversible is the shift in mouth form of roundworm, Pristionchus pacificus, when exposed to a changes in food type and availability. A second example of reversible developmental plasticity is the length of Galapagos marine iguanas, Amblyrhynchus cristatus, in response to El Niño weather conditions. During El Niño seasons, the algal food supply decreases, but increases during La Niña seasons. This change in food availability coincides with the changes in iguana size during the season.
A unique and complex example of plasticity is camouflage, an adaption that allows animals to avoid predators by hiding in plain sight. The mechanisms behind camouflage are not the same in all species - they can be morphological, physiological, behavioral, or even a combination of traits. Camouflage can also be irreversible or reversible, depending on the species. Camouflage can be irreversible when color patterns or other morphological traits are set during development. However, camouflage can also be reversible, with color, texture, and behavioral changes occurring in response to immediate threats (e.g., Mimic octopus).
In some cases, the exact same change in phenotype can be reversible in one species and irreversible in another. For example, both pea and wheat plants express changes in root growth due to environmental cues, but the changes are permanent only for wheat. Sometimes this can even occur within the same species, due to the largely unpredictable results of interactions between an individual's genetic make-up and their specific environmental experiences.
Leaf development
Dicerandra linearifolia leaves grown at the beginning of its development, with lower ambient temperature, are thicker, wider, and possess less stomata than those grown later in the same year.
Root density
In times of sporadic nutrient availability, fine root density increases in order to more efficiently absorb nutrients. In times of water inundation, plants will increase root mass in response to make use of the excess water in the environment.
Nutrient resorption
Plants are capable of adjusting the degree nutrients are reabsorbed from their leaves. Resorption tends to be incomplete in nutrient-rich environments, and conversely nutrient poor environments often trigger complete resorption in plants.
Leaf morphology
Leaves grown during the dry season differ than those grown in wetter seasons. The leaves differ in their shape (leaves grown during the dry season were longer and narrower in comparison to those grown during the wet season), possessed higher trichome density, and lower anthocyanin levels.
References
Developmental biology
Physiology | Temporal plasticity | [
"Biology"
] | 1,125 | [
"Behavior",
"Developmental biology",
"Physiology",
"Reproduction"
] |
71,928,301 | https://en.wikipedia.org/wiki/PlayStation%20VR2 | The PlayStation VR2 (PS VR2) is a virtual reality headset for the PlayStation 5 and PC, developed by Sony Interactive Entertainment and released on February 22, 2023.
History and development
Development of PS VR2 took about six years, and was developed simultaneously alongside the PlayStation 5, with the goal to craft the perfect match of a console and a virtual reality device with "PC connection in mind". Leading up to the PS VR2 release, a display analyst from the Display Supply Chain Consultants (DSCC), said that he expected the upcoming next generation VR headset to have a display with the highest pixel density on a commercial OLED panel, with pixel density "well above 800 PPI".
At the 2022 Consumer Electronics Show, Sony announced the PlayStation VR2 for the PlayStation 5. A release date of February 22, 2023, and a retail price of $549.99 was announced on November 2, 2022 at the official PlayStation Blog.
On February 22, 2024, Sony announced that PC support will be coming to PlayStation VR2 in August 2024. The PlayStation VR2 PC adapter was released on August 7, 2024 through selected retailers to mixed reviews, with issues including lack of various features such as eye tracking and HDR, incompatibility with some bluetooth adapters and motherboards, poor bluetooth reception and the additional cost required (from the adapter and controllers) to connect the PSVR2 to a PC. Eurogamer reportedly encountered a Bluetooth issue pairing the PC with the PSVR2 controllers.
On December 8, 2024, Bloomberg News reported that Sony were in discussions about making the PSVR2 controllers compatible with the Apple Vision Pro, which could also result in the controllers finally being sold separately from the headset.
Sales
In May 2023, Sony announced that slightly less than 600,000 units of PlayStation VR2 has been sold to consumers during its first 6 weeks from launch.
According to IDC, 595,500 units were shipped by Q1 2023, 435,300 in Q2 2023, 343,600 units in Q3 2023 and 325,200 units in Q4 2023 (1,699,600 accumulative units shipped in 2023). As of March 18, 2024, Bloomberg reported that Sony has paused the manufacture of PSVR2 after making well over 2 million units.
Hardware
The headset connects to the PlayStation 5 console through a single USB-C cable that negotiates 12 V via Power Delivery and simultaneous USB 3 data and video via DisplayPort alt-mode, which enables a simple plug and play design. The cable length is 4.5 m (14.7 ft). Sony stated that while they are still researching the technical possibility of a wireless connection, due to concerns about its impact on performance, they chose to go with the cable solution. Compared to the first generation PS VR, the headset overall weight has been reduced, while the headband underwent many design improvements to increase its comfort. The FOV was also increased to approx. 110 degrees.
The headset has a built-in microphone and a stereo 3.5mm headphone jack. Using the PS5 Tempest 3D AudioTech, the headset supports 3D audio through headphones, allowing the in-game audio to dynamically adapt to the user position and head movements. Additionally, the headset has a cooling system that incorporates a duct and a small fan to cool the onboard IC chip. In addition to cooling the IC chip, this airflow also provides ventilation to help minimize the lenses fogging up while the player is wearing the headset.
The play area for PS VR2 can be customized using the cameras and the Sense controller. There are three different "VR Play Styles" depending on the game content and compatibility–sitting, standing or room-scale (the last one allowing more movement while playing).
Vision
The PS VR2 has dual OLED panels with a "4K" display resolution and 90 Hz/120 Hz refresh rate. Each display has a resolution of 2,000 x 2,040 pixels and also supports HDR. Similar to the original PS VR, the new PS VR2 also features a Social Screen, which allows others to see what the player is experiencing in a 2D format on a TV screen. Cinematic Mode is also supported, which is used to view all non-VR game and media contents on a virtual cinema screen at 1920x1080 @ 120 Hz HDR.
The headset uses fresnel lenses. These lenses "act on microscopic level to significantly reduce ghosting" and "allow for a beautiful image without sacrificing brightness". PS VR2 has a lens adjustment dial, which allows the headset to accommodate different IPD measurements. The facial interface of the headset was also designed to be able to accommodate different head shapes and nose sizes, and it can be removed from the PS VR2 headset for cleaning.
Tracking and feedback
Unlike the first generation PlayStation VR, which tracked player movements through an external PlayStation Camera, the PS VR2 tracks movements via four cameras on the front of the headset. These same cameras are also used to track the controllers, and to give video feed for the "see-through view" feature, which allows the user to view their surroundings without needing to take off the headset. The headset also has two inward-facing IR cameras. These are used for eye-tracking to enable games to utilize foveated rendering, a performance optimization technique where the render resolution of the game is reduced in areas where the player is not looking. The eye-tracking can also be used as an input method, such as for selecting UI elements with a glance.
PS VR2 also features headset feedback through a built-in motor, which provides subtle haptic effects for added immersion, such as "feeling the character's heartbeat or feeling the rush of objects passing close to the head". Some sources have pointed out that Sony have previously registered patents which mentioned using haptics to reduce motion sickness.
Controlling
PS VR2 uses the new Sense controllers. The controller was designed with a focus on balancing the center of gravity and reducing weight, while also maintaining comfort and incorporating new features. The controller is shaped like an "orb or hollowed-out sphere", which is used to ideally place a ring of 14 IR LEDs that is used for tracking its position and orientation. The controller has several features, including key features from the DualSense controller, like its haptic feedback and adaptive triggers technology. Another new feature is the finger touch detection, which can detect the approximate location of the fingers, enabling the user to make more natural gestures during gameplay. This is achieved by using five capacitive finger touch sensors on each controller (four sensors for each button, and one sensor for the analog stick) to detect the placements of the thumb, index, and the middle finger.
Games and content
Sony announced that more than 100 games are in development, with over 30 titles available at the launch window, including Resident Evil Village, The Walking Dead: Saints & Sinners – Chapter 2: Retribution, Five Nights at Freddy's: Help Wanted 2, No Man's Sky, Star Wars: Tales from the Galaxy's Edge, Demeo, Moss and Moss: Book II remasters, and PS VR2 exclusives Horizon Call of the Mountain and The Dark Pictures: Switchback VR. Gran Turismo 7 and Beat Saber have also been updated to work with PS VR2.
Gran Turismo 7 was also confirmed to have a full game support on the PS VR2 (except for the 2-player splitscreen mode). This is in contrast to the previous game in the series, Gran Turismo Sport, which was only supported by the original PS VR headset in a very limited capacity.
PS VR2 is not compatible with the previous generation PS VR games. Sony said that due to the differences in both the controller tracking hardware and the image rendering principle, porting games from the previous hardware would not be easy. When connected to a PC with the PSVR2 PC adapter, PS VR2 users can gain access to thousands of VR games on Steam.
Reception
Pre-release reviews were mostly positive, lauding the many improvements over its predecessor and its advanced technology. The lack of backward compatibility and the price of the headset received mixed reaction. Various game developers praised the capabilities of the headset, particularly in combination with the PlayStation 5. The new Sense controllers received acclaim from CNET, while Eurogamer singled out the HDR OLED screen for its brightness and contrast, stating that "it now feels more comparable to a proper high-end OLED TV". Some reviewers criticized the inconvenience of the wired connection. While the launch library was described as "solid" by CNN, The Telegraph had some concerns about future first party software plans beyond the current offering.
On Metacritic, out of 51 professional critic reviews, 14 were in the "Extremely positive" category, 33 in the "Positive" category, 4 in the "Mixed" category, and 0 in the "Negative" category.
In regard to the software, previews of the exclusive title Gran Turismo 7 were positive, with Motorsport.com describing it as "the best console virtual reality experience to date".
XR Games and Sony Pictures VR took home Best in Gaming and Best in the World (across all categories) for the VR Shooter Zombieland: Headshot Fever Reloaded at The Australian XR Festival Awards 2023.
In June 2024, Jay Peters from The Verge wrote "I regret buying the PSVR 2". Digital Trend's reporter stated his unit was "collecting dust".
See also
List of PlayStation VR2 games
References
External links
Official website
PlayStation 5 accessories
Computer peripherals
Products introduced in 2022
Virtual reality headsets
Video game console add-ons | PlayStation VR2 | [
"Technology"
] | 2,014 | [
"Computer peripherals",
"Components"
] |
71,928,465 | https://en.wikipedia.org/wiki/ZTF%20J1813%2B4251 | ZTF J1813+4251 is a binary star system including a star and white dwarf, co-orbiting every 51 minutes, about 3,000 light years away in the constellation of Hercules. It is considered a cataclysmic variable with the white dwarf pulling outer layers of hydrogen from the star onto itself. It has the shortest orbital period of all hydrogen-rich cataclysmic variable stars known. It is predicted that the orbital period will reach a minimum of 18 minutes within 75 million years as the system evolves.
It was identified in 2022 by Kevin Burdge of MIT using a computer algorithm that searched over 1,000 images from the Zwicky Transient Facility, identifying stars that had brightness variability periods around one hour.
References
External links
Astronomers find a “cataclysmic” pair of stars with the shortest orbit yet
Scientists spot ‘cataclysmic star pair’ whirring around each other in spectacular dance
"Cataclysmic" Pair Of Stars With Shortest Known Orbit Discovered
Two Stars Orbiting Each Other Every 51 Minutes. This Can’t End Well
Cataclysmic variable stars
Hercules (constellation)
Astronomical objects discovered in 2022 | ZTF J1813+4251 | [
"Astronomy"
] | 242 | [
"Hercules (constellation)",
"Constellations"
] |
71,929,189 | https://en.wikipedia.org/wiki/Anisotropic%20terahertz%20microspectroscopy | Anisotropic terahertz microspectroscopy (ATM) is a spectroscopic technique in which molecular vibrations in an anisotropic material are probed with short pulses of terahertz radiation whose electric field is linearly polarized parallel to the surface of the material. The technique has been demonstrated in studies involving single crystal sucrose, fructose, oxalic acid, and molecular protein crystals in which the spatial orientation of molecular vibrations are of interest.
Explanation
When the electric field of a propagating beam of light oscillates in a direction perpendicular to its direction of propagation, it is said to be a polarized transverse wave. Light with an electric field constrained to a particular angle in the transverse plane is said to be linearly polarized. When linearly polarized light is transmitted through an isotropic material — a material that exhibits the same physical properties in all spatial directions — the amount of light absorbed by the material is the same when measured for all angles of the polarized light. The resulting absorbance spectrum is featureless as a function of the polarization angle.
A material said to be anisotropic exhibits different physical properties, like absorbance, refractive index, conductivity and so on, along different spatial directions. Thus, when a linearly polarized beam of light is passed through an anisotropic material and measured for different angles of polarization, the absorption of the light is different for different polarization angles. The resulting absorbance spectrum exhibits varying degrees of absorbance that correspond to the materials degree of anisotropy.
When a polarized THz beam of light is transmitted through an anisotropic material, the resulting absorbance spectrum exhibits varying degrees of absorbance that correspond to the anisotropy of the material. If measurements are made at different frequencies across the THz spectrum (between about 0.3 to 3 THz) at a particular THz polarization angle, the resulting absorbance spectrum may also vary with frequency. This occurs because the vibrational modes of the molecules in the material absorb light at different frequencies. In protein molecules, for example, many of these vibrational modes oscillate within the range of terahertz frequencies. When the molecules in a material are arranged in the same orientation, the internal vibrational properties of the molecules may be identified using anisotropic terahertz microspectroscopy (ATM). This molecular alignment is found in single crystals of sucrose, fructose, oxalic acid, and other molecular crystals like protein crystals.
Techniques
To date, ATM techniques have utilized THz time-domain spectroscopy (THz-TDS) because of historical scarcity of strong THz sources and highly sensitive THz detectors that operate at room temperature. Many samples of interest contain large amounts of water that strongly absorb THz radiation, thus requiring a very strong THz source. This requirement is exacerbated when attempting to use highly sensitive THz detectors that conventionally require supercooling to liquid helium temperatures. Worse, the need for supercooling these detectors has made THz detection unavailable to many researchers around the world due to recent sharp rises in the price of liquid helium due to its scarcity.
To circumvent THz detection hurdles, THz-TDS is utilized as it requires commonly available infrared detectors sensitive in the near infrared region of the electromagnetic spectrum — most commonly around a wavelength of 800 nm. In this case, an electro-optic (EO) crystal, such as gallium nitride (GaN), zinc telluride (ZnTe), is commonly used to detect changes in the THz light after it has passed through a sample. The polarization properties of a synchronized infrared beam of light passing through the EO crystal are changed. This polarization change is detected by an infrared detector, called a balanced detector, that compares the magnitude of two perpendicular polarization components of the infrared beam.
Until more powerful THz sources that provide a wide frequency range and more sensitive room temperature THz detectors are realized, THz-TDS remains a reliable technique for ATM.
The THz-TDS techniques used in ATM may be divided into two categories: rotated sample and stationary sample. Historically, the former technique involved rotation of the sample at the focus of a THz beam while the detector is placed far from the sample in the far-field. For many mechanical reasons, however, a stationary sample technique is preferred. In stationary sample ATM, a polarized THz beam is rotated through 360° in a plane perpendicular to the propagation direction of the beam and typically utilizes a near-field detection scheme in which the sample is mounted in direct contact with an EO crystal that is subsequently analyzed by the infrared beam in a THz-TDS configuration.
Rotated Sample ATM
Original ATM techniques involve rotating the sample at the focal point of a linearly polarized THz beam using a mechanically rotated sample mount. For this reason, the configuration is typically a far-field instrument in which a balanced detector (sensitive to infrared light) is placed a considerable distance from the sample. In the terahertz time-domain spectroscopy configuration, both the infrared and THz beams are transmitted through an electro-optic (EO) crystal like ZnTe or GaP. Here, the infrared beam detects the change in birefringence of the EO crystal due to the THz beam. When a sample is placed in the THz beam, the polarized THz beam is perturbed and the resulting degree of birefringence in the EO crystal is changed. The resulting perturbation of the infrared beam is sensed at the balanced detector.
Rotated sample ATM is very useful for large samples (0.1 to 1 cm). However, when measuring samples such as protein crystals that must be isolated inside a hydration chamber, for example, the sample cannot be easily rotated. Additionally, it is challenging to maintain the same location of a rotated sample at the precise focal point of a THz beam.
Instrument Design
An ATM designed with a rotated sample is typically a far-field measurement configuration using a time-domain spectroscopy strategy.
A high power infrared laser is typically used. Its beam is split by a beamsplitter into two optical paths: a probe beam and a THz generation beam.
The THz generation beam typically receives the greater fraction of NIR power in order to maximize the power of the THz light commonly generated by a voltage-pulsed photoconductive antenna. The generated THz light is collected through a hyper-hemispherical silicon lens and passed to an off-axis parabolic mirror that collimates the THz beam for polarization by a THz polarizer that is often made of a simple wire-grid. The linearly polarized THz beam is then focused by a second off-axis parabolic mirror onto the sample. The THz beam transmitted through the sample is again collected by a third off-axis parabolic mirror, collimated onto a fourth parabolic mirror that then focuses the beam onto an electro-optic (EO) crystal whose birefringence is perturbed by the strength of the THz beam.
The NIR probe beam is passed through the EO crystal to probe the induced degree of birefringence caused by the THz beam and passed to a detection module that often consists of an NIR quarter wave plate, a Wollaston prism that spatially separates orthogonal polarization states of the probe beam into two optical paths that are individually detected at a balanced detector. The resulting signal reported by the balanced detector is a measure of the difference in magnitude of these two orthogonal components of the NIR probe beam and therefore a direct correlation of the degree of birefringence induced in the EO crystal by the THz beam passed through the sample.
Stationary Sample ATM
Previously called "ideal ATM" and "polarization-varying ATM," stationary sample ATM (SSATM) involves rotation of the linearly polarized state of the THz beam in a time-domain spectroscopy (TDS) configuration parallel to the interrogated material sample. In a SSATM configuration, the THz beam polarization is rotated through 360° in a plane perpendicular to the propagation direction of the beam. Measurements of the sample's anisotropy is measured at several THz polarization angles.
At least two methods to achieve THz polarization rotation for SSATM have been demonstrated: 1) by using a THz quarter waveplate (THz-QWP) together with an infrared polarizer and 2) by rotating the photoconductive antenna.
In the case of employing a THz-QWP and an infrared polarizer, the magnitude of the measured signal, , where is a time delay between THz generation and the detected pulses in a THz-TDS system is dependent on the relative polarization angle of the THz light, and the polarization angle of the ultrafast near-infrared (NIR) probe beam, , at the sample by the relationship
The objective is to maintain equal magnitude of the THz electric field at the sample for all measurement angles, . This requires adjustment of for every .
Instrument Design
A SSATM instrument is typically designed in a time-domain spectroscopy configuration in which a high power infrared laser beam is divided into two optical paths by a beamsplitter.
The first optical path often receives a greater fraction of the optical power of the laser to maximize the output power of generated THz light. THz light is often generated with a voltage-pulsed photoconductive antenna, collected with a hyper-hemispherical silicon lens, collimated using an off-axis parabolic mirror that is then passed through a THz polarizer, made circular by a THz quarter waveplate constructed of two planar mirrors and a right-angled high-resistivity silicon prism to form circularly polarized light. A second THz polarizer selects from the circularly polarized THz light the angle at which each measurement is made once the light reaches a sample located at a focal point of the beam and mounted in direct contact with an electro-optic crystal often made of either ZnTe or GaP.
The second optical path includes a retroreflector mirror mounted on a delay stage that adjusts the time-of-flight of the NIR beam to match the delay time, , of the THz light at the sample. The NIR beam is linearly polarized and chopped at a frequency suitable for detection, directed to the EO crystal to measure the change in its birefringence due to the degree of THz absorption by the sample. The NIR beam is reflected by the sample/EO crystal interface and directed to the detection module that often consists of an NIR quarter waveplate, a Wollaston prism that spatially selects perpendicular polarization states of the light toward two detectors in a balanced detector. The detected signal is a measure of the difference of the magnitude of the two perpendicular polarization states and corresponds to the degree of birefringence induced in the EO crystal by the THz light as-perturbed by the sample.
THz Quarter Waveplate
One strategy to provide full 360° rotation of THz polarization of equal electric field magnitude at the sample is to generate a circular state of polarization, then select particular linear polarization states from the circularly polarized beam with a THz polarizer.
A circular polarization state may be generated by a quarter waveplate, however, common optical waveplates are typically designed for visible, near- and mid-infrared regions of the electromagnetic spectrum. A quarter waveplate designed for use in the THz frequency range consists of a right-angle silicon prism together with metal-coated planar mirrors as input/output. In particular, the silicon prism acts analogously to a Fresnel rhomb with a single total internal reflection on the longer face of the prism and is a passive broadband component that permits a wide frequency sweep during measurements.
Advantages
A few advantages of ATM over other related microspectroscopy techniques include the orientation of the THz electric field at the sample and the ability to readily measure materials that are sensitive to environmental conditions like hydration, cryo-cooling, and evacuation.
THz polarization orientation at the sample
A key characteristic of ATM is the orientation of the polarized electric field of THz light at the sample. In particular, unlike other microspectroscopy techniques like scattering scanning near-field optical microscopy (s-SNOM), the electric field of the interrogating THz field is parallel to the surface of the sample. In s-SNOM, the shape of the oscillating metallic probe tip directs the THz polarization into a direction predominantly perpendicular to the sample surface.
Environmentally sensitive sample materials
Living organisms typically consist of large quantities of water. Many anisotropic materials of interest are biological in nature and as such require hydration during spectroscopic measurements. While some limited novel techniques to measure properties of materials inside a hydrated sample chamber have been recently reports, the primary design requirement of ATM is that the material is accessible through a window that is transparent to THz light such as quartz. Similarly, samples requiring cryo-cooling or low pressure vacuum environment are readily interrogated in ATM using THz-transparent window materials.
Applications
Anisotropic terahertz microspectrosopy (ATM) has found applications in structural biology and molecular fingerprinting of DNA and proteins. The technique is also suitable for drug discovery and studying THz frequency properties of thin film solid state materials.
Special attention is given to molecular motions in proteins where many structural changes occur at frequencies in the terahertz range of the spectrum (0.3 THz to 3 THz). These structural changes include hinge motions in which two regions of molecules are connected together by a flexible molecular structure that bends like a mechanical hinge or elbow. ATM is uniquely capable of measuring the spatial direction in which hinge motions occur because of its use of linearly polarized electric fields.
Protein dynamics
ATM is uniquely suited to measure resonant molecular vibrations in proteins. Molecular motions in proteins occur with frequencies in the terahertz range of the spectrum (0.3 THz to 3 THz). These structural changes include hinge motions in which two regions of molecules are connected together in a flexible way that bends like a mechanical hinge or joint and other conformational changes that occur within systems of protein molecules.
Protein molecules are typically surrounded by water molecules and are arranged in random orientations. For this reason, it is common to arrange protein molecules in crystal form such that their orientations all the same. In particular, in a protein crystal the dipole of all protein molecules are naturally aligned. This allows us to perform microspectroscopy with polarized THz light and ascertain the spatial orientation of vibrations within molecules.
References
Terahertz technology
Spectroscopy
Scientific techniques | Anisotropic terahertz microspectroscopy | [
"Physics",
"Chemistry"
] | 3,084 | [
"Molecular physics",
"Spectrum (physical sciences)",
"Instrumental analysis",
"Electromagnetic spectrum",
"Spectroscopy",
"Terahertz technology"
] |
71,929,357 | https://en.wikipedia.org/wiki/Apache%20Iceberg | Apache Iceberg is a high performance open-source format for large analytic tables. Iceberg enables the use of SQL tables for big data while making it possible for engines like Spark, Trino, Flink, Presto, Hive, Impala, StarRocks, Doris, and Pig to safely work with the same tables, at the same time. Iceberg is released under the Apache License. Iceberg addresses the performance and usability challenges of Apache Hive tables in large and demanding data lake environments. Vendors currently supporting Apache Iceberg tables include Buster, CelerData, Cloudera, Crunchy Data, Dremio, IOMETE, Snowflake, Starburst, Tabular, AWS, and Google Cloud.
History
Iceberg was started at Netflix by Ryan Blue and Dan Weeks. Hive was used by many different services and engines in the Netflix infrastructure. Hive was never able to guarantee correctness and did not provide stable atomic transactions. Many at Netflix avoided using these services and making changes to the data to avert unintended consequences from the Hive format. Ryan Blue set out to address three issues that faced the Hive table by creating Iceberg:
Ensure the correctness of the data and support ACID transactions.
Improve performance by enabling finer-grained operations to be done at the file granularity for optimal writes.
Simplify and abstract general operation and maintenance of tables.
Iceberg development started in 2017. The project was open-sourced and donated to the Apache Software Foundation in November 2018. In May 2020, the Iceberg project graduated to become a top-level Apache project.
Iceberg is used by multiple companies including Airbnb, Apple, Expedia, LinkedIn, Adobe, Lyft, and many more.
See also
List of Apache Software Foundation projects
References
Apache Software Foundation projects
SQL
Free system software
Hadoop
Cloud platforms
Java platform | Apache Iceberg | [
"Technology"
] | 378 | [
"Cloud platforms",
"Computing platforms",
"Java platform"
] |
71,929,531 | https://en.wikipedia.org/wiki/Inverse%20lithography | In semiconductor device fabrication, the inverse lithography technology (ILT) is an approach to photomask design. It is basically an approach to solve an inverse imaging problem: to calculate the shapes of the openings in a photomask ("source") so that the passing light produces a good approximation of the desired pattern ("target") on the illuminated material, typically a photoresist. As such, it is treated as a mathematical optimization problem of a special kind, because usually an analytical solution does not exist. In conventional approaches known as the optical proximity correction (OPC) a "target" shape is augmented with carefully tuned rectangles to produce a "Manhattan shape" for the "source", as shown in the illustration. The ILT approach generates curvilinear shapes for the "source", which deliver better approximations for the "target".
The ILT was proposed in 1980s, however at that time it was impractical due to the huge required computational power and complicated "source" shapes, which presented difficulties for verification (design rule checking) and manufacturing. However in late 2000s developers started reconsidering ILT due to significant increases in computational power.
References
Lithography (microfabrication)
Inverse problems | Inverse lithography | [
"Materials_science",
"Mathematics"
] | 258 | [
"Microtechnology",
"Applied mathematics",
"Inverse problems",
"Nanotechnology",
"Lithography (microfabrication)"
] |
71,930,047 | https://en.wikipedia.org/wiki/Calcarisporiellales | Calcarisporiellaceae is a family of fungi within the subkingdom Mucoromycota. It is the only family in the order Calcarisporiellales, class Calcarisporiellomycetes, subphylum Calcarisporiellomycotina and phylum Calcarisporiellomycota. It contains two known genera, Calcarisporiella and Echinochlamydosporium. The two genera each have one species.
General description
They have a thallus that is branched, with septate (has a singular septum) hyphae. The vegetative hyphae is hyaline (has a glassy appearance), smooth and thin-walled. It has cultures with no distinctive smell. The sporangiophores (a receptacle in ferns which bears the sporangia, if present) simple, hyaline, smooth, arising from undifferentiated hyphae. The sporangia is unispored, ellipsoid (in shape), with or without a small columella. Spores are uninucleate (having a single nucleus), hyaline, smooth, thin-walled, ovoid to ellipsoid, with a rounded base. Chlamydospores (if present) are 1-celled, elongate to globose, thick-walled and spiny, and are born laterally on short hyphae. The sexual cycle not known, but they are saprotrophic in soil and non-nematophagous (not carnivorous).
It can be found in soils.
History
Calcarisporiella was originally published in 1974 and originally thought to be an anamorphic member of the Pezizomycotina division, but later phylogenetic analysis of rDNA found that it was separate from the Endogonales and Mucorales clades.
A new genus, Echinochlamydosporium, was described in 2011 and placed in Mortierellaceae family. Then in 2018, after molecular analyses, Echinochlamydosporium was transferred to a new family Calcarisporiellaceae with Calcarisporiella.
The newly described Calcarisporiellomycota (comprising Calcarisporiella thermophila and Echinochlamydosporium variabile) represented a deep lineage with strongest affinities to Mucoromycota or Mortierellomycota.
Evolution and systematics
The Calcarisporiellaceae are a monophyletic group containing two species. According to a 2018 phylogenetic analysis, they are the sister taxon of the phylum Mucoromycota. Along with Mortierellomycota and Glomeromycota, they compose the fungal subkingdom Mucoromyceta.
Phylum Calcarisporiellomycota
Subphylum Calcarisporiellomycotina
Class Calcarisporiellomycetes
Order Calcarisporiellales
Family Calcarisporiellaceae
Calcarisporiella
Calcarisporiella thermophila
Echinochlamydosporium
Echinochlamydosporium variabile
References
External links
Fungi
Fungus orders
Taxa described in 2018 | Calcarisporiellales | [
"Biology"
] | 703 | [
"Fungi"
] |
71,930,908 | https://en.wikipedia.org/wiki/Ileodictyon%20gracile | Ileodictyon gracile is a saprotrophic species of fungus in the family Phallaceae. It is native to Australia, where it is commonly known as the smooth cage fungus, with reference to its basidiocarps (fruit bodies), shaped like a ball with interlaced or latticed branches partly covered on the inner surfaces with a foetid slime layer containing basidiospores.
Ileodictyon gracile is similar to and sometimes confused with Ileodictyon cibarium, which is also native to Australia. Fruit bodies of both species are whitish, mesh balls of similar size, but can be differentiated by characteristics of the receptacle arms that form the mesh. I. cibarium has a thicker mesh with arms that are wrinkled, wider, elliptical in cross section, and not thickened where the arms meet, compared to I. gracile.
Distribution
Ileodictyon gracile is native to Australia, but is not known with certainty from New Zealand. The species has also been found in Asia, in China, India, Japan, and Korea, possibly as a result of it being introduced. It is also known in Europe from England, Italy, Portugal, and Spain where it is certainly introduced.
References
Phallales
Fungi of Australia
Fungi described in 1845
Fungus species | Ileodictyon gracile | [
"Biology"
] | 277 | [
"Fungi",
"Fungus species"
] |
71,933,242 | https://en.wikipedia.org/wiki/Competitive%20Carriers%20Association | The Competitive Carriers Association (commonly the CCA) was founded in 1992 by nine small wireless carriers in the United States as a 501(c)(6) non-profit trade association to promote the common interests of competitive, regional, and rural wireless services providers. Its counterpart, particularly for non-regional wireless carriers, is the CTIA.
History
The organization was founded in 1992 as the Rural Carriers Association (RCA), but became the Competitive Carriers Association in 2012 as national carriers Sprint and T-Mobile US joined. It has long advocated for policies and standards that promote greater competitive in the wireless industry, particularly with regard to issues around wireless spectrum.
References
External links
Telecommunications organizations
Wireless networking
Trade associations based in the United States
Trade shows in the United States
1992 establishments in the United States
Organizations established in 1992
501(c)(6) nonprofit organizations
Non-profit organizations based in Washington, D.C. | Competitive Carriers Association | [
"Technology",
"Engineering"
] | 183 | [
"Wireless networking",
"Computer networks engineering"
] |
61,076,234 | https://en.wikipedia.org/wiki/Elena%20Boldyreva | Elena Vladimirovna Boldyreva (born 4 February 1961) is a Russian chemist. Boldyreva is a leading researcher at the Boreskov Institute of Catalysis in the Siberian Branch of Russian Academy of Sciences, and is Professor and Head of the Section of Solid State Chemistry at Novosibirsk State University.
Early life and education
Boldyreva was born in Tomsk. She attended secondary school #130 and graduated with a gold medal in 1977. She studied at the Novosibirsk State University, and earned her bachelor's degree in 1982 and PhD in physical chemistry in 1988. Boldyreva worked at the Russian Academy of Sciences from 1980.
Research and career
Boldyreva was awarded an additional Doctorate in Science in solid-state chemistry in 2000. She was promoted to Professor at the Novosibirsk State University in 2003. Her early work considered photomechanical effects in crystals of coordination complexes. She shifted into high pressure research, working with infrared spectroscopy at the Phillips University in Marburg. Boldyreva has investigated solid pharmaceutical compounds and biomimetic molecules. She also worked at Durham University as a Royal Society Fellow.
She uses high pressure measurements to investigate and control the inter- and intra-molecular interactions in crystals. She has shown you can use pressure to induce new crystalline forms, as well as interrogating chemical reactions. Alongside experimental science, Boldyreva works on Monte Carlo simulations for solid-state reactions.
She serves on the advisory council of the Russian Ministry of Education and Science.
She is an editor for Acta Crystallographica, International Union of Crystallography Research Journal, CrystEngComm Journal of Thermal Analysis and Calorimetry and Pharmalogica.
Awards and honours
Her awards and honours include;
2007 Award from the European Society for Applied Physical Chemistry
2008 Elected to the International Union of Crystallography
2012 Academina Women in Science
2017 Elected to the Slovenian Academy of Sciences and Arts
2018 University of Edinburgh Honorary degree of Doctor of Science
2018 Elected to the Academia Europaea
Books
References
1961 births
Living people
Solid state chemists
Novosibirsk State University alumni
Academic staff of Novosibirsk State University | Elena Boldyreva | [
"Chemistry"
] | 439 | [
"Solid state chemists"
] |
61,076,754 | https://en.wikipedia.org/wiki/Vanadium%20oxydichloride | Vanadium oxydichloride is the inorganic compound with the formula VOCl2. One of several oxychlorides of vanadium, it is a hygroscopic green solid. It is prepared by comproportionation of vanadium trichloride and vanadium(V) oxides:
V2O5 + VOCl3 + 3 VCl3 → 6 VOCl2
As verified by X-ray crystallography, vanadium oxydichloride adopts a layered structure, featuring octahedral vanadium centers linked by doubly bridging oxide and chloride ligands.
From VOCl2, various blue or green-colored oxotri- and oxotetrachloride salts can be prepared. Examples include N(CH3)4VOCl3 and the pyridinium derivative (C5H5NH)2VOCl4.
References
Vanadium(IV) compounds
Oxychlorides
Metal halides | Vanadium oxydichloride | [
"Chemistry"
] | 208 | [
"Inorganic compounds",
"Metal halides",
"Salts"
] |
61,078,954 | https://en.wikipedia.org/wiki/Red%20Hook%20Wi-Fi | Red Hook Wi-Fi is a free-to-use, Wi-Fi mesh network that provides internet access to the Red Hook neighborhood of Brooklyn, New York. It is operated by the Red Hook Initiative.
Background
Due to the location of Red Hook, Brooklyn, between the Red Hook Channel and the Buttermilk Channel, many of its residents face various challenges in accessing broadband service. A survey found out that many people in the area accessed the internet primarily through mobile phones and that over 30% of the population did not have broadband access at home.
Beginning in Fall 2011, the Red Hook Initiative (RHI), a Brooklyn non-profit, approached the Open Technology Institute about collaborating on a community wireless network. RHI wanted a way to communicate with the residents immediately around its community center.
When the network was initially launched, it had support for up to 150 simultaneous users and ran on an open-software platform called Commotion.
Hurricane Sandy
In 2012, after Hurricane Sandy struck the area, and many internet and communication systems were down throughout much of the city, Red Hook remained connected through its mesh network and the headquarters of the Red Hook Initiative became a hub for volunteer coordination, donation collections food distribution as residents came to the Red Hook Initiative's office to charge their devices and connect to the internet.
Shortly afterwards, the Federal Emergency Management Agency (FEMA) connected Red Hook Wi-Fi to its satellite system, linking itself, the residents and the Red Cross into a communication matrix that could be used to find out about emergency relief, food banks as well as shelter locations.
After the relief efforts had finished, a team led by the Red Hook Initiative continued to make improvements to the mesh network by installing nano stations powered by solar panels on rooftops around the Red Hook neighborhood.
Though the Red Hook Wi-Fi project was already in the works before Hurricane Sandy struck, it gained additional media attention after the storm.
In 2015, Red Hook Wi-Fi was selected to be part of the city's resiliency initiative — from a group of 27 finalists competing in the Resiliency Innovations for a Stronger Economy.
References
External links
Mesh networking
Red Hook, Brooklyn
Community networks | Red Hook Wi-Fi | [
"Technology"
] | 437 | [
"Wireless networking",
"Mesh networking"
] |
61,079,098 | https://en.wikipedia.org/wiki/Macropodid%20alphaherpesvirus%201 | Macropodid alphaherpesvirus 1 (MaHV-1) is a species of herpesvirus in the genus Simplexvirus. It was officially accepted as a valid species by the International Committee on Taxonomy of Viruses in 2004.
Hosts
It has been detected in captive parma wallabies (Macropus parma) while some other marsupial species have been found to be susceptible to infection when experimentally inoculated.
See also
Macropodid alphaherpesvirus 2
References
Further reading
Alphaherpesvirinae | Macropodid alphaherpesvirus 1 | [
"Biology"
] | 106 | [
"Virus stubs",
"Viruses"
] |
61,079,121 | https://en.wikipedia.org/wiki/Macropodid%20alphaherpesvirus%202 | Macropodid alphaherpesvirus 2 (MaHV-2) is a species of herpesvirus in the genus Simplexvirus. It was officially accepted as a valid species by the International Committee on Taxonomy of Viruses in 2004.
Hosts
Macropodid alphaherpesvirus 2 has been detected in two species of captive macropods: grey dorcopsis (Dorcopsis luctuosa) and quokkas (Setonix brachyurus).
See also
Macropodid alphaherpesvirus 1
References
Further reading
Alphaherpesvirinae | Macropodid alphaherpesvirus 2 | [
"Biology"
] | 112 | [
"Virus stubs",
"Viruses"
] |
61,079,306 | https://en.wikipedia.org/wiki/Town%20of%20Salem | Town of Salem is an online multiplayer game with social deduction and strategy elements. It was developed and published by indie game developer BlankMediaGames, and released on December 15, 2014. Early alpha and beta versions were browser-based and free-to-play. On October 14, 2018, the game was released for iOS and Android mobile devices after a successful and long-supported Kickstarter fundraiser.
Town of Salem is reportedly the largest online version of the classic social deduction party game Werewolf, with over 5 million registered users as of June 2017.
Town of Salem 2 was announced on April 23, 2023. It was released on Steam Early Access on May 26, 2023, and fully released with a free demo on July 26, 2023.
The Town of Salem IP is now owned by the video game publisher Digital Bandidos as of August 5, 2024.
Gameplay
The game is based on the party games Werewolf and Mafia, in which players are secretly assigned roles belonging to teams of an informed minority and uninformed majority. Both teams seek to eliminate the other for control of the town. The chief strategy of the game is to survive and accomplish win conditions. Players use a combination of role abilities, teamwork, communication, deduction and deception to facilitate their victory.
In the base-game, there are three role alignments: Town, Mafia and Neutral. Each player is randomly assigned a role, which determines their goal for the game. The Mafia's goal is to kill all the townspeople, while the Town's goal is to find and eliminate the Mafia before they can do so. Neutral roles have their own unique goals which may or may not conflict with the Town and Mafia.
A match consists of rounds that cycle between night and day. Most roles have a unique ability which they can use during the night, such as protecting another player or learning their identity. The Mafia may kill during the night, and all players have the opportunity to write notes in their will.
During the day, the wills of players that died the previous night are revealed. Then, players use what they have learned to accuse someone of being evil. If that player is found guilty, they are publicly lynched and their will is revealed. The game continues until one side achieves their win condition.
Development
BlankMediaGames LLC was founded in 2014 by Josh Brittain and Blake Burns. A Kickstarter campaign began on February 14, 2014, to develop Town of Salem. After thirty days, the fundraiser raised $17,190 with a goal of $15,000. The game was released that year, and reached 800,000 active monthly users by 2016.
On September 13, 2014, the developers started a fundraiser for a Steam release, with a goal of $30,000. The fundraiser finished in 35 days, raising $114,197 from 7,506 backers. The Steam version was released on December 14. The web version of Town of Salem was free-to-play, while the Steam version was not.
On November 3, 2018, the free web version transitioned to a paid model. Accounts that were previously obtained for free were grandfathered in and remained active. BlankMediaGames stated that the reason for this change was to combat spam and bot attacks plaguing the game.
As of March 2020, nine game modes are available. The game is for groups of 7-15 players, and features 50 different roles (including those from The Coven expansion pack).
As of July 2024, as developing company BlankMediaGames has been acquired by publisher Digital Bandidos, ownership and control of the game has passed to the publisher. It announced partnership with developer BlankMediaGames in August 2024, with the aim of bringing Town of Salem 2 to mobile.
Ports
On March 31, 2016, another Kickstarter fundraiser began after the release of a mobile beta version of the game. The fundraiser sought to support further development towards a finished mobile version. On September 28, 2018, after two years in development, a launch trailer for the mobile game was released on YouTube. The game, now using a Unity base code, was released free-to-play on the Apple App Store and Google Play on October 14. It featured an extensive overhaul of the UI to one that was more ergonomic, had more and improved animations, and better graphics.
On April 2, 2019, BlankMediaGames announced development of a Unity version of the web browser and Steam games due to the discontinuation of Adobe Flash Player in 2020. The opt-in beta version became available only on Steam on July 24. On October 28, 2019, the Steam Unity client was officially released. The formerly free-to-play Flash-based web version was still available for several months afterward. On May 28, 2020, the browser-based client was also updated to use the Unity engine.
Town of Salem – The Card Game
On April 15, 2016, fundraising began for a card game version of Town of Salem. It raised $389,005 from 9,551 backers in 30 days, surpassing its of goal of $10,000. The card game is more akin to the original Mafia party game, in which players close their eyes during nighttime and take turns using their abilities with the help of a human moderator.
The Coven
On May 16, 2017, the expansion pack The Coven was announced. The expansion added a new faction, the Coven, fifteen new roles, and three new game modes. Two roles from the expansion, the Ambusher and Hypnotist, were eventually added to Classic on October 20, 2020. The expansion pack released in June 2017 for $10, with a 50% discount for players who purchased the game through Steam.
Data breach
A data breach that affected over 7.6 million Town of Salem accounts was exposed in an email to security firm DeHashed on December 28, 2018. The breach involved a compromise of the servers and access to a database which included 7,633,234 unique email addresses. The database also contained IP addresses, passwords and payment information. Some users who paid for premium features also reportedly had their billing information and data breached. Investigative reporter Brian Krebs linked the hackers to Apophis Squad, a gang who made bomb threats against thousands of schools and launched distributed denial-of-service (DDoS) attacks.
Town of Salem 2
Town of Salem 2, the sequel to Town of Salem, was announced on April 23, 2023, for release on Steam only. The sequel removes the Mafia faction in favor of the Coven, with most Mafia roles being merged into the Coven. A new player faction, the Apocalypse, opposes both the Town and Coven, with the Plaguebearer and Juggernaut roles from the original game's Coven expansion incorporated into this new faction with two roles completely new to the game.
The sequel offers more customization options, with players being able to purchase interior and path decorations for their houses in the shop, as well as move their character around freely in the lobby and after death in-game. Communication is improved, with the ability to tag players, keywords, and roles in chat, aiding in the discussion during the day. Town of Salem 2 released for iOS and Android devices on March 26, 2024.
On a Steam blog post, BlankMediaGames revealed that Town of Salem 2 matched its predecessor's all-time high concurrent Steam user count, reaching over 3,700 concurrent players. The developers also revealed that sales for the game exceeded that of Town of Salem's Coven DLC and its mobile port launch.
Reception
In 2020, PC Gamer named Town of Salem one of the best free-to-play browser games. They described it as difficult to explain, but easy to get the hang of. Matt Cox of Rock, Paper, Shotgun described the game as "an online hidden role game with no friends or eyeballs, and a whole load of bullshit." Cox went on to criticize the game for being too complicated, and said that the experience "feels empty" due to the lack of face-to-face interaction.
References
External links
2014 video games
Android (operating system) games
IOS games
MacOS games
Multiplayer video games
Social deduction video games
Role-playing video games
Indie games
Salem witch trials in fiction
Strategy video games
Asymmetrical multiplayer video games
Video games developed in the United States
Video games set in Massachusetts
Video games set in 17th-century Thirteen Colonies
Video games set in the 1690s
Windows games
Video games about witchcraft
Mafia (party game) | Town of Salem | [
"Physics"
] | 1,733 | [
"Asymmetrical multiplayer video games",
"Symmetry",
"Asymmetry"
] |
61,082,099 | https://en.wikipedia.org/wiki/NGC%206789 | NGC 6789 is a void irregular galaxy in the constellation Draco. It was discovered by Lewis Swift on Aug 30, 1883. It is located within the Local Void, a region of space with far fewer galaxies than its surroundings.
NGC 6789 is the nearest blue compact dwarf (BCD) galaxy to the Milky Way. It is chemically homogeneous and relatively metal-poor.
See also
List of NGC objects (6001–7000)
References
External links
Irregular galaxies
Draco (constellation)
6789 | NGC 6789 | [
"Astronomy"
] | 106 | [
"Galaxy stubs",
"Astronomy stubs",
"Constellations",
"Draco (constellation)"
] |
61,082,102 | https://en.wikipedia.org/wiki/NGC%201487 | NGC 1487 is an irregular galaxy in the constellation Eridanus. It was discovered by James Dunlop on Oct 29, 1826.
It is thought to be the remnant of two galaxies, which are the components NGC 1487E and NGC 1487W, that collided about 500 million years ago.
See also
List of NGC objects (1001–2000)
Gallery
References
External links
Interacting galaxies
Spiral galaxies
Eridanus (constellation)
1487
Dorado Group
014117 | NGC 1487 | [
"Astronomy"
] | 95 | [
"Eridanus (constellation)",
"Constellations"
] |
61,082,104 | https://en.wikipedia.org/wiki/NGC%203245 | NGC 3245 is a lenticular galaxy in the constellation Leo Minor. It was discovered by William Herschel on April 11, 1785. It is a member of the NGC 3254 Group of galaxies, which is a member of the Leo II Groups, a series of galaxies and galaxy clusters strung out from the right edge of the Virgo Supercluster.
See also
List of NGC objects (3001–4000)
References
External links
Lenticular galaxies
Leo Minor
3245
030744 | NGC 3245 | [
"Astronomy"
] | 100 | [
"Leo Minor",
"Constellations"
] |
61,082,105 | https://en.wikipedia.org/wiki/NGC%204781 | NGC 4781 is a barred spiral galaxy in the constellation Virgo. It was discovered by William Herschel on Mar 25, 1786. It is a member of the NGC 4699 Group of galaxies, which is a member of the Virgo II Groups, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster.
See also
List of NGC objects (4001–5000)
References
External links
Barred spiral galaxies
Virgo (constellation)
4781
043902 | NGC 4781 | [
"Astronomy"
] | 107 | [
"Virgo (constellation)",
"Constellations"
] |
61,082,106 | https://en.wikipedia.org/wiki/NGC%203898 | NGC 3898 is a spiral galaxy in the constellation Ursa Major that was discovered by William Herschel on April 14, 1789. It is positioned 1.5° northwest of NGC 3998 and is barely visible in a small telescope. The galaxy has an apparent visual magnitude of 10.7 and an angular size of . It is located at a distance of from the Milky Way, and is receding with a heliocentric radial velocity of .
The morphological classification of NGC 3898 in the De Vaucouleurs system is SA(s)ab, which indicates this is a spiral galaxy with no central bar (SA) or inner ring system (s) and tightly wound spiral arms (ab). It is gas rich and serves as the prototype of an Sa galaxy with flocculent arms. The galactic plane is inclined at an angle of to the plane of the sky, with the major axis oriented along a position angle of 107°. The nucleus is intermediate between an H II region and a LINER.
There is a small, irregular galaxy, UGC 6816, located at an angular separation of from NGC 3898.
Gallery
References
External links
Unbarred spiral galaxies
3898
Ursa Major
036921 | NGC 3898 | [
"Astronomy"
] | 253 | [
"Ursa Major",
"Constellations"
] |
61,082,109 | https://en.wikipedia.org/wiki/NGC%201345 | NGC 1345 is a barred spiral galaxy in the constellation Eridanus. It was discovered by John Herschel on Dec 11, 1835.
See also
List of NGC objects (1001–2000)
References
External links
Barred spiral galaxies
Eridanus (constellation)
1345
012979 | NGC 1345 | [
"Astronomy"
] | 60 | [
"Eridanus (constellation)",
"Constellations"
] |
61,082,111 | https://en.wikipedia.org/wiki/NGC%205678 | NGC 5678 is a barred spiral galaxy in the constellation Draco. It was discovered by William Herschel on April 17, 1789.
See also
List of NGC objects (5001–6000)
References
External links
Barred spiral galaxies
Draco (constellation)
5678 | NGC 5678 | [
"Astronomy"
] | 56 | [
"Constellations",
"Draco (constellation)"
] |
61,082,112 | https://en.wikipedia.org/wiki/NGC%201249 | NGC 1249 is a barred spiral galaxy in the constellation Horologium. It was discovered by John Herschel on December 5, 1834.
See also
List of NGC objects (1001–2000)
References
External links
Barred spiral galaxies
Horologium (constellation)
1249
Dorado Group
011836
Dwarf spiral galaxies
Magellanic spiral galaxies | NGC 1249 | [
"Astronomy"
] | 72 | [
"Constellations",
"Horologium (constellation)"
] |
61,082,113 | https://en.wikipedia.org/wiki/NGC%201425 | NGC 1425, also known as IC 1988, is a spiral galaxy around 71 million light-years away in the constellation Fornax. It was discovered by William Herschel on Oct 9, 1790, and it belongs to the Fornax cluster.
See also
List of NGC objects (1001–2000)
References
External links
Unbarred spiral galaxies
1425
IC objects
Fornax
013602 | NGC 1425 | [
"Astronomy"
] | 84 | [
"Fornax",
"Constellations"
] |
61,082,114 | https://en.wikipedia.org/wiki/NGC%203294 | NGC 3294 is a spiral galaxy in the constellation Leo Minor. It was discovered by William Herschel on Mar 17, 1787. It is a member of the Leo II Groups, a series of galaxies and galaxy clusters strung out from the right edge of the Virgo Supercluster. The galaxy is located at a distance of 98 million light years and is receding with a heliocentric radial velocity of . The morphological class of NGC 3294 is SA(rs)bc, which means this is a spiral galaxy with no central bar (SA), an incomplete inner ring structure (rs), and moderately wound spiral arms (bc).
This galaxy has been host to a pair of supernova events:
SN 1990H was discovered by Saul Perlmutter and Carlton Pennypacker on April 9, 1990 at a position west and south of the galactic nucleus. The spectrum and light curve resembled a type II core-collapse supernova similar to SN 1987A.
SN 1992G was discovered by Shunji Sasaki on 14 February 14 1992, east and south of the galaxy's nucleus. This was determined to be a type Ia supernova.
References
External links
Unbarred spiral galaxies
Leo Minor
3294
031428 | NGC 3294 | [
"Astronomy"
] | 252 | [
"Leo Minor",
"Constellations"
] |
61,082,116 | https://en.wikipedia.org/wiki/NGC%20918 | NGC 918 is a barred spiral galaxy in the constellation Aries, about 67 million light years from the Milky Way. It was discovered by John Herschel on Jan 11, 1831.
The brightness class of NGC 918 is III and it has a broad line of neutral hydrogen. NGC 918 is also an active nucleus galaxy (AGN). Moreover, it is a field galaxy; that is to say, it does not belong to a cluster or group and is therefore gravitationally isolated.
Many non-redshift measures give a distance of 19,115 ± 6,160 Mpc (~62,3 million ly), which is within the distances calculated using the value shift.
Two supernovae have been observed in this galaxy. SN 2009js (type II, mag. 17.2) was discovered on October 11, 2009. This was the first subluminous supernova to be studied in infrared wavelengths. Supernova SN 2011ek (type Ia, mag. 16.4) was discovered on Aug. 4, 2011 by Kōichi Itagaki.
References
External links
Barred spiral galaxies
Aries (constellation)
918
009236 | NGC 918 | [
"Astronomy"
] | 240 | [
"Aries (constellation)",
"Constellations"
] |
61,082,237 | https://en.wikipedia.org/wiki/Biomass%20allocation | Biomass allocation is a concept in plant biology which indicates the relative proportion of plant biomass present in the different organs of a plant. It can also be used for whole plant communities.
Rationale
Different organs of plants serve different functions. Leaves generally intercept light and fix carbon, roots take up water and nutrients, and stems and petioles display the leaves in a favourable position and transport various compounds within the plant. Depending on environmental conditions, plants may change their investment scheme, to make plants with relatively bigger root systems, or more leaves. This balance has been suggested to be a ‘functional equilibrium’, with plants that experience low water or nutrient supply investing more in roots, and plants growing under low light or CO2 conditions investing more in leaves or stems. Alternatively, it is also known as the 'balanced growth hypothesis', or the 'optimal partitioning theory'. Next to environmentally-induced changes, there are also inherent differences in biomass allocation between species, and changes that depend on the age or size of plants.
Related concepts
Biomass allocation is the result of a number of processes which take place in the plant. It starts with the way sugars are allocated to different organs after having been fixed by the leaves in the process of photosynthesis (sugar allocation). Conceptually this is simple to envisage, but to quantify the flow of sugars is challenging and requires sophisticated machinery. For plants growing under steady state conditions, it is feasible to determine sugar-allocation by constructing a C-budget. This requires determination of the C-uptake by the whole plant during photosynthesis, and the C-losses of shoots and roots during respiration. Further C-losses may occur when sugars and other C-based compounds are exuded by the roots, or disappear as volatiles in the leaves. When these measurements are combined with growth measurements and the C-concentrations present in the biomass of leaves, stems and roots, C-budgets can be constructed from which sugar allocation is derived.
These C-budgets are instructive, but require extensive measurements. A next level of analysis is to measure the growth allocation: what is the increase in total biomass of a plant, and to what extent is the increase due to growth of leaves, of stems and of roots. In young plants, growth allocation is often quite similar to the actual biomass allocation. But especially in trees, there may be a high yearly turnover in leaves and fine roots, and a low turnover in stems, branches and thick roots. In those cases, the allocation of growth and the final biomass allocation may diverge quite strongly over the years.
There have been attempts to give these three different levels of allocation different names (a.o. partitioning, distribution, fractionation), but so far they have been applied inconsistently.
The fractions of biomass present in leaves and roots are also relevant variables in Plant growth analysis.
Calculation and units
A common way to characterize the biomass allocation of a vegetative plant is to separate the plant in the organs of interest (e.g. leaves, stems, roots) and determine the biomass of these organs – generally on a dry mass basis - independently. The Leaf Mass Fraction (LMF) is then calculated as leaf dry mass / total plant dry mass, the Stem Mass Fraction (SMF) as stem dry mass / total plant dry mass, and Root Mass Fraction (RMF) as root dry mass / total plant dry mass. Generally, units are g g−1 (g organ / g total plant biomass).
For generative plants, there is the additional compartment related to reproduction (flowers and flower stalks, seeds or fruits). The relative amount of biomass present in this compartment is often indicated as 'Reproductive Effort'. A related variable which is often used in agronomy is the 'Harvest index'. Because roots are seldom harvested, the harvest index is the amount of marketable product (often the seeds), relative to the total above-ground biomass.
Alternative terminology that has been used are Leaf, Stem and Root Mass Ratios, or shoot:root or root:shoot ratios. The latter two convey less information, as they do not discriminate between leaves and stems.
Normal ranges
Young herbaceous plants generally have LMF values in the range of 0.3–0.7 g g−1 (0.5 on average), SMF values ranging from 0.04 - 0.4 (0.2 on average), and RMF values between 0.1 and 0.5 (0.3 on average). Young tree seedlings have values in the same range. For older and bigger plants, the LMF decreases and SMF increases. For large trees (> 1000 kg) LMF is below 0.05, SMF around 0.8 and RMF around 0.2 g g−1. At that stage most of the stem biomass consists of highly lignified material, which still may serve the important function of contributing to the support function of stems, but is physiologically not active anymore.
Environmental effects
The effect of the environment generally is as expected from the ‘functional equilibrium’ concept: plants decrease LMF and increase RMF when grown at high light levels as compared to low light. At low nutrient levels they invest more in roots and less in leaves as compared to high nutrient supply. However, changes are often smaller at different water supply, and effects of CO2 concentration, UV-B radiation, ozone and salinity on allocation are generally negligible. Plants growing at higher temperature mostly decrease RMF and increase LMF.
A point of attention in the analysis of mass fractions is whether or not to correct for differences in size, when comparing plants that have been treated differently, or in the comparison of species. The rationale behind this is that mass factions often change with plant size (and developmental phase), and different treatments may have caused growth differences as well. Thus, for an assessment of whether plants actively changed their allocation scheme, plants of similar size should be compared. If size corrections are required, one could do an allometric analysis. A simple alternative is to plot mass fractions against total plant mass.
Differences between species
Species of different families may have different allocation patterns. For example, species belonging to the Solanaceae have high LMF values, whereas Fagaceae have low LMF values, even after size-corrections. Grasses generally have lower LMF values that herbaceous dicots, with a much higher proportion of their biomass present in roots. Large evergreen trees have a larger fraction of their biomass allocated to leaves (LMF ~0.04) than deciduous species (LMF ~0.01).
See also
Allometry
Biomass partitioning
Plant growth analysis
References
Biomass
Plant ecology
Plant physiology | Biomass allocation | [
"Biology"
] | 1,381 | [
"Plant physiology",
"Plant ecology",
"Plants"
] |
61,085,382 | https://en.wikipedia.org/wiki/C38H38O16 | {{DISPLAYTITLE:C38H38O16}}
The molecular formula C38H38O16 (molar mass: 750.70 g/mol, exact mass: 750.2160 u) may refer to:
Dicerandrol C
Phomoxanthone A (PXA)
Phomoxanthone B (PXB)
Molecular formulas | C38H38O16 | [
"Physics",
"Chemistry"
] | 78 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,086,513 | https://en.wikipedia.org/wiki/Amino%20%28app%29 | Amino is a social media application originally developed by Narvii, Inc. It was originally created by Yin Wang and Ben Anderson in 2012, and then launched as an app in 2016. Amino was acquired by MediaLab in January 2021, and the founders are no longer associated with the application.
History
In 2012, Wang and Anderson came up with the idea for a convention-like community while attending an anime convention in Boston, Massachusetts. Later that year, they would release two apps revolving around K-pop and photography that allowed fans of those subjects to chat freely.
In 2012, Amino was officially released.
Growth
Amino received 1.65 million dollars of seed funding in 2014, primarily from Union Ventures. Some additional seed investors include Google Ventures, SV Angel, Box Group, and other interested parties.
By July 2014, Amino's apps were downloaded 500,000 times. Though only having 15 communities at that time, Amino eventually grew to have 41 communities in September 2015. Amino's apps had been downloaded 13 million times by July 2016. Fandoms had migrated from websites like Facebook and Reddit to Amino, partly because of the app's mobile-native experience.
Before 2016, when a user wanted to join a new Amino, they had to download another app for the Amino they wanted to join. In 2016, Amino Apps launched a centralized portal that hosted every Amino community in one app, meaning users no longer had to download multiple apps.
In July of the same year, ACM, an app that allowed users to create their own communities, was launched. This resulted in the number of communities on Amino skyrocketing to over 2.5 million as of June 2018.
Features
The main feature of Amino is communities dedicated to a certain topic that users can join. Users can also chat with other members of a community in three ways, text, voice, or screening room, which allows users to watch videos together while voice chatting. Other features include polls, blog posts, image posts, wiki entries, stories, and quizzes. In some cases, posts that are very well-made and have been noticed by a community's administration will end up receiving a feature, making it appear on the front page along with other featured content.
In 2018, a premium membership option called Amino+ was added. Amino+ comes with additional features such as exclusive stickers, the ability to make stickers, custom chat bubbles, high resolution images, and other perks. Membership can be purchased with money or Amino coins. Amino coins can be purchased or earned through enabling ads, watching ad videos, completing activities on the Offer Wall, and playing Lucky Draw when checking in. Members can give and receive coins through props.
In 2019, Amino introduced six original short-form animated series, labelled "Amino Originals," produced by independent artists from across the internet. ATJ's "Little Red," a re-imagining of Little Red Riding Hood, premiered on November 15, 2019. "Little Red" was joined by five other shows in late December. Sophie Feher's "The Reef," a comedy featuring an aspiring marine biologist meeting a merman, premiered on December 27 alongside "Princely," an LGBT fairy tale created by Matt Bruneau-Richardson of Tiny Siren Animation. "Spaced Out," an alien abduction comedy by Michael Jae, and YouTuber Alex Clark's "Wyndvania II" premiered on December 28. Mysie Pereira's fairy tale "Turned to Stone" and Marcin Pawlowski's "Stranded" premiered on December 29, 2019.
Administration
On each community, there are two types of staff members, these being ‘Leader’ and ‘Curator.’ Leaders are higher rank than curators. Curators are usually the ones who feature posts, or post important announcements for users to see.
Curators are able to disable a post or public chat, delete comments or chat threads, manage featured content, manage posts in topic categories, and approve Wiki entries.
Leaders have more power than curators. In addition to curator powers, leaders can submit a community to be listed, change the Amino's features, change navigation, alter the community appearance, change the Amino's privacy settings, manage the Amino's join requests, send invites, appoint or demote Curators, strike or ban members, manage flagged content, change users' custom titles, manage topics and wiki categories, and create broadcasts (notifications sent for posts).
One leader will have the status of agent. An agent is the primary leader of a community; the person who created the community is automatically agent. An agent has the ability to delete their community as long as it is not too large or too active. An agent can appoint and remove both leaders and curators. Agent status can be transferred voluntarily to another leader, curator, or community member. If an agent is inactive, Team Amino may assist in transferring agent status.
Apps
Amino Community Manager
Otherwise known as ACM, this application is what users use to create and manage their own community in Amino. This app allows moderators to customize a community's theme, icon, and categories. ACM also allows moderation to customize community descriptions, pick leaders, change language settings, create a tagline for the community, change the home page lay out, alter the side navigation menu, and more. Unlisted communities are able to change their community's title and Amino ID, but this is not an option once a community is listed. A leader can use ACM to submit a request for their community to be listed on the explore page, after which the community will be reviewed by Team Amino for approval. Communities can be deleted on ACM, but only by the agent of that community.
Guidelines
Amino has a set of guidelines that all communities must comply with. Amino does not allow harassment or hate, spam or self-promotion (including promotion of one's own Amino community), sexual/NSFW content*, self harm, real graphic/gross content (fictional content is generally acceptable), unsafe/illegal content, or content that violates copyright. Communities are allowed to have additional rules so long as they do not violate Amino's rules. In addition to Amino's rules, users are required to be at least 13 years of age in the U.S. and 16 years of age in European Union countries. While sexual imagery is not allowed in any community and text based sexual content is not allowed in public areas, some private communities are allowed to discuss sexual themes. However, they are not exempt from Amino's rules on NSFW content.
If guidelines are broken, a leader may disable content or impose a warning, strike, or ban, depending on the severity of the infringement. A warning is a message informing the user that they have violated a guideline and may face further punishment unless they change their behaviour. A strike will put the user in read-only mode for up to 24 hours; this mode prevents the user from posting, chatting, or interacting with posts in that community. A ban removes the user from the community. Team Amino can separately give strikes or bans across the entire platform.
References
Social media
Social networking mobile apps | Amino (app) | [
"Technology"
] | 1,470 | [
"Computing and society",
"Social media"
] |
61,086,978 | https://en.wikipedia.org/wiki/Mycena%20lazulina | Mycena lazulina is a bioluminescent species of mushroom in the genus Mycena and family Mycenaceae.
It was first described in 2016 from southwestern Japan. The specific epithet, lazulina, is Latin for blue (c.f. lapis lazuli).
See also
List of bioluminescent fungi
References
External links
Mycena lazulina in Mycobank
Gallery of images at The Forum of Fungi
Bioluminescent fungi
lazulina
Fungi described in 2016
Fungus species | Mycena lazulina | [
"Biology"
] | 107 | [
"Fungi",
"Fungus species"
] |
54,727,043 | https://en.wikipedia.org/wiki/Simplicial%20depth | In robust statistics and computational geometry, simplicial depth is a measure of central tendency determined by the simplices that contain a given point. For the Euclidean plane, it counts the number of triangles of sample points that contain a given point.
Definition
The simplicial depth of a point in -dimensional Euclidean space, with respect to a set of sample points in that space, is the number of -dimensional simplices (the convex hulls of sets of sample points) that contain .
The same notion can be generalized to any probability distribution on points of the plane, not just the empirical distribution given by a set of sample points, by defining the depth to be the probability that a randomly chosen -tuple of points has a convex hull that This probability can be calculated, from the number of simplices that by dividing by where is the number of sample points.
Under the standard definition of simplicial depth, the simplices that have on their boundaries count equally much as the simplices with in their interiors. In order to avoid some problematic behavior of this definition, proposed a modified definition of simplicial depth, in which the simplices with on their boundaries count only half as much. Equivalently, their definition is the average of the number of open simplices and the number of closed simplices that
Properties
Simplicial depth is robust against outliers: if a set of sample points is represented by the point of maximum depth, then up to a constant fraction of the sample points can be arbitrarily corrupted without significantly changing the location of the representative point. It is also invariant under affine transformations of the plane.
However, simplicial depth fails to have some other desirable properties for robust measures of central tendency. When applied to centrally symmetric distributions, it is not necessarily the case that there is a unique point of maximum depth in the center of the distribution. And, along a ray from the point of maximum depth, it is not necessarily the case that the simplicial depth decreases monotonically.
Algorithms
For sets of sample points in the Euclidean plane
the simplicial depth of any other point can be computed in time
optimal in some models of computation.
In three dimensions, the same problem can be solved in time
It possible to construct a data structure using ε-nets that can approximate the simplicial depth of a query point (given either a fixed set of samples, or a set of samples undergoing point insertions) in near-constant time per query, in any dimension, with an approximation whose error is a small fraction of the total number of triangles determined by the samples. In two dimensions, a more accurate approximation algorithm is known, for which the approximation error is a small multiple of the simplicial depth itself. The same methods also lead to fast approximation algorithms in higher dimensions.
Spherical depth, is defined to be the probability that a point is contained inside a random closed hyperball obtained from a pair of points from . While the time complexity of most other data depths grows exponentially, the spherical depth grows only linearly in the dimension – the straightforward algorithm for computing the spherical depth takes . Simplicial depth (SD) is linearly bounded by spherical depth ().
References
Computational geometry
Robust statistics | Simplicial depth | [
"Mathematics"
] | 669 | [
"Computational geometry",
"Computational mathematics"
] |
54,727,095 | https://en.wikipedia.org/wiki/Cumulative%20accuracy%20profile | A cumulative accuracy profile (CAP) is a concept utilized in data science to visualize discrimination power. The CAP of a model represents the cumulative number of positive outcomes along the y-axis versus the corresponding cumulative number of a classifying parameter along the x-axis. The output is called a CAP curve. The CAP is distinct from the receiver operating characteristic (ROC) curve, which plots the true-positive rate against the false-positive rate.
CAPs are used in robustness evaluations of classification models.
Analyzing a CAP
A cumulative accuracy profile can be used to evaluate a model by comparing the current curve to both the 'perfect' and a randomized curve. A good model will have a CAP between the perfect and random curves; the closer a model is to the perfect CAP, the better it is.
The accuracy ratio (AR) is defined as the ratio of the area between the model CAP and random CAP, and the area between the perfect CAP and random CAP. In a successful model, the AR has values between zero and one, and the higher the value is, the stronger the model.
The cumulative number of positive outcomes indicates a model's strength. For a successful model, this value should lie between 50% and 100% of the maximum, with a higher percentage for stronger models. In sporadic cases, the accuracy ratio can be negative. In this case, the model is performing worse than the random CAP.
Applications
The cumulative accuracy profile (CAP) and ROC curve are both commonly used by banks and regulators to analyze the discriminatory ability of rating systems that evaluate credit risks. The CAP is also used by instructional design engineers to assess, retrain and rebuild instructional design models used in constructing courses, and by professors and school authorities for improved decision-making and managing educational resources more efficiently.
References
Mathematical modeling | Cumulative accuracy profile | [
"Mathematics"
] | 366 | [
"Applied mathematics",
"Mathematical modeling"
] |
54,728,895 | https://en.wikipedia.org/wiki/Loncastuximab%20tesirine | Loncastuximab tesirine, sold under the brand name Zynlonta, is a monoclonal antibody conjugate medication used to treat large B-cell lymphoma and high-grade B-cell lymphoma. It is an antibody-drug conjugate (ADC) composed of a humanized antibody targeting the protein CD19.
The most common side effects include increased levels of gamma-glutamyltransferase (GGT, a liver enzyme), neutropenia (low levels of neutrophils, a type of white blood cell), tiredness, anemia (low levels of red blood cells), thrombocytopenia (low levels of blood platelets), nausea (feeling sick), peripheral edema (swelling due to fluid retention, especially of the ankles and feet) and rash.
Loncastuximab tesirine was approved for medical use in the United States in April 2021, and in the European Union in December 2022. The US Food and Drug Administration (FDA) considers it to be a first-in-class medication.
Medical uses
Loncastuximab tesirine is indicated for the treatment of adults with relapsed or refractory large B-cell lymphoma and high-grade B-cell lymphoma.
Technology
The humanized monoclonal antibody is stochastically conjugated via a valine-alanine cleavable, maleimide linker to a cytotoxic (anticancer) pyrrolobenzodiazepine (PBD) dimer. The antibody binds to CD19, a protein which is highly expressed on the surface of B-cell hematological tumors including certain forms of lymphomas and leukemias. After binding to the tumor cells the antibody is internalized, the cytotoxic drug PBD is released and the cancer cells are killed. PBD dimers are generated out of PBD monomers, a class of natural products produced by various actinomycetes. PBD dimers work by crosslinking specific sites of the DNA, blocking the cancer cells’ division that cause the cells to die. As a class of DNA-crosslinking agents they are significantly more potent than systemic chemotherapeutic drugs.
History
The benefit and side effects of loncastuximab tesirine were evaluated in one clinical trial, ADCT-402-201 (LOTIS-2 / NCT03589469), that included 145 participants with relapsed or refractory diffuse large B-cell lymphoma after at least two prior treatments that did not work or were no longer working. Participants received loncastuximab tesirine 0.15 mg/kg every 3 weeks for 2 treatment cycles, then 0.075 mg/kg every 3 weeks for subsequent treatment cycles. Loncastuximab tesirine treatment was continued until either disease worsened or participants experienced unacceptable side effects (toxicity). The benefit of loncastuximab tesirine was evaluated by measuring how many participants had complete or partial tumor shrinkage (response) and by how long that response lasted. Participants in the clinical trial were also evaluated for side effects for the purpose of this drug application. Trials were conducted at 28 sites in the United States, the United Kingdom, Italy, and Switzerland.
Loncastuximab tesirine was granted orphan drug designation by the FDA for the treatment of diffuse large B-cell lymphoma. Loncastuximab tesirine was approved under FDA's accelerated approval program.
Society and culture
Legal status
On 15 September 2022, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion, recommending the granting of a marketing authorization for the medicinal product Zynlonta, intended for the treatment of adults with diffuse large B-cell lymphoma (DLBCL) and high-grade B-cell lymphoma (HGBL). The applicant for this medicinal product is ADC Therapeutics (NL) B.V. Loncastuximab tesirine was approved for medical use in the European Union in December 2022.
Research
Given its mechanism of action, loncastuximab tesirine may be appealing in patients ineligible for CAR-T cell therapy.
References
External links
Antibody-drug conjugates
Monoclonal antibodies for tumors
Orphan drugs | Loncastuximab tesirine | [
"Biology"
] | 952 | [
"Antibody-drug conjugates"
] |
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