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4,129,051 | https://en.wikipedia.org/wiki/Phaeno%20Science%20Center | The Phæno Science Center is an interactive science center in Wolfsburg, Germany, completed in 2005.
The Phæno Science Center
The building was designed by the Iraqi-British architect Zaha Hadid, cost 67 million euros[1] and was realised in a project partnership with the Lörrach-based architectural firm Mayer Bährle. After just over four years of construction, the permanent exhibition was opened on 24 November 2005. Over 350 interactive experiment stations (around 40 of which were designed by artists) allow visitors to experience science and technology with different senses. The approximately 9000 square metre exhibition is divided into the main themes of ‘Life, Vision, Energy, Dynamics, Sense, Maths’. Changing special exhibitions complement the themes. In addition to the large exhibition, phaeno also offers workshops and training courses for schoolchildren, educators and teachers. The pupils solve puzzles, carry out experiments or work on constructive tasks and are accompanied by two members of staff[2][3].
In addition to science talks, science slams and lectures[4], the phaeno Science Theatre also offers a variety of shows. These are demonstrations with live experiments that represent a specific topic, e.g. the laser, air, mechanics, water or even fire show[5].
In line with the educational concept, according to which a playful approach to phenomena best promotes understanding, there is no prescribed course. Simple experimental arrangements encourage visitors to understand the respective functions by thinking about them and not just by trying them out. Display and text panels (German and English) at each station explain the respective process. The entrance area, the ideas forum and the science theatre are located on the ground floor, above which is the main floor with the picnic area[6] and the ‘experimental landscape’. Another important area is the children's area, which consists of three levels and is suitable for children from around three years of age. While exhibits suitable for children invite them to explore and try things out on the upper two levels, the lowest level is a quiet area where children can give free rein to their creativity with everyday objects such as corks and clothes pegs[7].
In 2022, phaeno had around 228,000 visitors of all ages;[8] around 35% of visitors are groups and individuals, 38% families and 27% schools and nurseries.
The visitors themselves come from all parts of Germany, but overall around 90% of visitors come from within a radius of 150 kilometres from phaeno.[9] It is a recognised extracurricular place of learning.
Architecture
The massive but very dynamically designed building was essentially made of concrete and steel. Despite its 27,000 cubic metres of concrete, the building gives the impression of flowing and floating both inside and out. The building is 16 metres high and extends over a length of 170 metres. Ten conical concrete pillars (‘cones’) with a diameter of up to seven metres support the building. The pillars create a cave-like space for outdoor events. The cones are not solid but hollow and offer various functions, such as a science theatre or a forum for ideas. Inside the building, the perspectives change with every step through sloping walls, a kinked and uncovered steel girder roof structure, cursive viewing slits in solid exposed concrete walls and sloping niches. According to the architect Zaha Hadid, the building's all-round dynamism is intended to promote mental openness and mobility.
Translated with DeepL.com (free version)
Preliminary planning began in November 1998, and one year later Joe Ansel, an American consultant and designer, was approached to handle the exhibitions and other operational aspects of the project. An architectural design competition was held in January 2000 and the prominent architect Zaha Hadid won, in conjunction with structural engineers, Adams Kara Taylor. About five years later, Phæno opened to the public on November 24, 2005 with over 250 interactive exhibits from Ansel Associates, Inc. all enclosed in an astounding concrete structure designed by Zaha Hadid, her German associate, Mayer Bährle architects and Adams Kara Taylor. The architectural design has been described as a "hypnotic work of architecture - the kind of building that utterly transforms our vision of the future." The design won a 2006 RIBA European Award as well as the 2006 Institution of Structural Engineers Award for Arts, Leisure and Entertainment Structures.
The building stands on concrete stilts, allowing visitors to the Autostadt to pass through without interfering with the workings of the building. Phæno is connected to the Autostadt by a metal bridge accessed by escalators and stairs either side. The underside of Phæno and the "stilts" are illuminated.
Dr. Guthardt is now Phæno's first Executive Director. Phæno has enjoyed high attendance and broad public acceptance since its grand opening. The Science Center has a theme song, "Phaenomenal," which was written and performed by American singer/songwriter Amanda Somerville for the opening.
The Phæno was included on a list of the 7 wonders of the Modern World (objects built since 2000) by The Financialist.
Movie appearances
The Phaeno appears in the movie The International (2009) as headquarters of an Italian weapons company - digitally inserted in front to a cliff at the Iseo Lake.
The Phaeno also appears in the German disaster film (2013) as a large hadron collider.
The Phaeno appears in the Belgian-Dutch dystopian television series Arcadia (2023).
See also
List of science centers
References
Further reading
Barbara Linz. Science Spaces: Architecture & Design. Cologne: Daab, 2007.
Philip Jodidio. Hadid: Zaha Hadid, Complete Works, 1979-2013. Köln: Taschen, 2013.
Greg Lynn (ed.). Christos Passas, Patrik Schumacher and Greg Lynn discuss Phaeno Science Center. Montreal, Canadian Centre for Architecture, 2017.
External links
Zaha Hadid Architects
Finding aid for the Zaha Hadid Architects Phaeno Science Centre project records, Canadian Centre for Architecture
Architekturbüro Mayer-Bährle
Ansel Associates, Inc.
Science Center Celebrates an Industrial Cityscape - New York Times, November 28, 2005
Phaeno Science Center by transform
Zaha Hadid buildings
Science museums in Germany
Museums in Lower Saxony
Buildings and structures completed in 2005
Postmodern architecture
Modernist architecture in Germany
Event venues established in 2005
Buildings and structures in Wolfsburg
Neo-futurist architecture | Phaeno Science Center | [
"Engineering"
] | 1,333 | [
"Postmodern architecture",
"Architecture"
] |
4,129,444 | https://en.wikipedia.org/wiki/Dora%20%28case%20study%29 | Dora is the pseudonym given by Sigmund Freud to a patient whom he diagnosed with hysteria, and treated for about eleven weeks in 1900. Her most manifest hysterical symptom was aphonia, or loss of voice. The patient's real name was Ida Bauer (1882–1945); her brother Otto Bauer was a leading member of the Austro-Marxist movement.
Freud published a case study about Dora, Fragments of an Analysis of a Case of Hysteria (1905 [1901], Standard Edition Vol. 7, pp. 1–122; ).
Case history
Family background
Dora lived with her parents, who had a loveless marriage, but one which took place in close concert with another couple, Herr and Frau K, who were friends of Dora's parents. The crisis that led her father to bring Dora to Freud was her accusation that Herr K had made a sexual advance to her, at which she slapped his face—an accusation which Herr K denied and which her own father disbelieved.
Freud himself reserved initial judgement on the matter, and was swiftly told by Dora that her father had a relationship with Frau K, and that she felt he was surreptitiously palming her off on Herr K in return. By initially accepting her reading of events, Freud was able to remove her cough symptom; but by pressing her to accept his theory of her own implication in the complex interfamily drama, and an attraction to Herr K, he alienated his patient, who abruptly finished the treatment after 11 weeks, producing, Freud reported bitterly, a therapeutic failure.
Dreams
Freud initially thought of calling the case "Dreams and Hysteria", and it was as a contribution to dream analysis, a pendent to his Interpretation of Dreams, that Freud saw the rationale for publishing the fragmentary analysis.
Ida (Dora) recounted two dreams to Freud. In the first:
[a] house was on fire. My father was standing beside my bed and woke me up. I dressed quickly. Mother wanted to stop and save her jewel-case; but Father said: 'I refuse to let myself and my two children be burnt for the sake of your jewel-case.' We hurried downstairs, and as soon as I was outside I woke up.
The second dream is substantially longer:
I was walking about in a town which I did not know. I saw streets and squares which were strange to me. Then I came into a house where I lived, went to my room, and found a letter from Mother lying there. She wrote saying that as I had left home without my parents' knowledge she had not wished to write to me to say Father was ill. "Now he is dead, and if you like you can come." I then went to the station and asked about a hundred times: "Where is the station?" I always got the answer: "Five minutes." I then saw a thick wood before me which I went into, and there I asked a man whom I met. He said to me: "Two and a half hours more." He offered to accompany me. But I refused and went alone. I saw the station in front of me and could not reach it. At the same time, I had the unusual feeling of anxiety that one has in dreams when one cannot move forward. Then I was at home. I must have been travelling in the meantime, but I knew nothing about that. I walked into the porter's lodge, and enquired for our flat. The maidservant opened the door to me and replied that Mother and the others were already at the cemetery.
Freud reads both dreams as referring to Ida Bauer's sexual life—the jewel case that was in danger being a symbol of the virginity which her father was failing to protect from Herr K. He interpreted the railway station in the second dream as a comparable symbol. His insistence that Ida had responded to Herr K's advances to her with desire—"you are afraid of Herr K; you are even more afraid of yourself, of the temptation to yield to him", increasingly alienated her. According to Ida, and believed by Freud, Herr K himself had repeatedly propositioned Ida, as early as when she was 14 years old.
Ultimately, Freud sees Ida as repressing a desire for her father, a desire for Herr K, and a desire for Frau K as well. When she abruptly broke off her therapy—symbolically just on 1.1.1901, only 1 and 9 as Berggasse 19, Freud's address—to Freud's disappointment, Freud saw this as his failure as an analyst, predicated on his having ignored the transference.
One year later (April 1902), Ida returned to see Freud for the last time, and explained that her symptoms had mostly cleared up; that she had confronted the Ks, who confessed that she had been right all along; but that she had recently developed pains in her face. Freud added the details of this to his report, but still viewed his work as an overall failure; and (much later) added a footnote blaming himself for not stressing Ida's attachment to Frau K, rather than to Herr K, her husband.
Freud's interpretation
Through the analysis, Freud interprets Ida's hysteria as a manifestation of her jealousy toward the relationship between Frau K and her father, combined with the mixed feelings of Herr K's sexual approach to her. Although Freud was disappointed with the initial results of the case, he considered it important, as it raised his awareness of the phenomenon of transference, on which he blamed his seeming failures in the case.
Freud gave her the name 'Dora', and he describes in detail in The Psychopathology of Everyday Life what his unconscious motivations for choosing such a name might have been. His sister's nursemaid had to give up her real name, Rosa, when she accepted the job because Freud's sister was also named Rosa—she took the name Dora instead. Thus, when Freud needed a name for someone who could not keep her real name (this time, in order to preserve his patient's anonymity), Dora was the name that occurred to him.
Critical responses
Early polarisation
Freud's case study was condemned in its first review as a form of mental masturbation, an immoral misuse of his medical position. A British physician, Ernest Jones, was led by the study to become a psychoanalyst, gaining "a deep impression of there being a man in Vienna who actually listened to every word his patients said to him...a true psychologist". Carl Jung also took up the study enthusiastically.
Middle years
By mid-century, Freud's study had gained general psychoanalytic acceptance. Otto Fenichel, for example, cited her cough as evidence of identification with Frau K and her mutism as a reaction to the loss of Herr K. Jacques Lacan singled out for technical praise Freud's stressing of Dora's implication in "the great disorder of her father's world ... she was in fact the mainspring of it".
Erik Erikson, however, took issue with Freud's claim that Dora must necessarily have responded positively at some level to Herr K's advances: "I wonder how many of us can follow without protest today Freud's assertion that a healthy young girl would, under such circumstances, have considered Herr K's advances 'neither tactless nor offensive'."
Feminist and later criticisms
Second-wave feminism would develop Erikson's point, as part of a wider critique of Freud and psychoanalysis. Freud's comment that "This was surely just the situation to call up distinct feelings of sexual excitement in a girl of fourteen", in reference to Dora's being kissed by a "young man of prepossessing appearance", was seen as revealing a crass insensitivity to the realities of adolescent female sexuality.
Toril Moi was speaking for many when she accused Freud of phallocentrism, and his study of being a "Representation of Patriarchy"; while Hélène Cixous would see Dora as a symbol of "silent revolt against male power over women's bodies and women's language... a resistant heroine". (Catherine Clément, however, would argue that as a mute hysteric, in flight from therapy, Dora was surely far less of a feminist role model than the independent career woman Anna O.)
Even those sympathetic to Freud took issue with his inquisitorial approach, Janet Malcolm describing him as "more like a police inspector interrogating a suspect than like a doctor helping a patient". Peter Gay, too, would question Freud's "insistent tone... The rage to cure was upon him" and conclude that not only the transference but also his own countertransference needed more attention from Freud at this early stage of development of psychoanalytic technique.
Literature and popular culture
Literature
Dominik Zechner, 2020. "The Phantom Erection: Freud's Dora and Hysteria's Unreadabilities." In: Johanna Braun (ed.), Performing Hysteria. Leuven University Press, 2020. https://dx.doi.org/10.1353/book.78723.
Lidia Yuknavitc, 2012. Dora: a Headcase. A novel based on the case, from a contemporary perspective sympathetic to Dora.
Katz, Maya Balakirsky (2011). "A Rabbi, A Priest, and a Psychoanalyst: Religion in the Early Psychoanalytic Case History". Contemporary Jewry 31 (1): 3–24. doi:10.1007/s12397-010-9059-y
Hélène Cixous, Portrait de Dora, des femmes 1976, Translated into English as Portrait of Dora Routledge 2004,
Charles Bernheimer, Claire Kahane, In Dora's Case: Freud-Hysteria-Feminism: Freud, Hysteria, Feminism, Second Edition, Columbia University Press, 1990
Hannah S. Decker, Freud, Dora, and Vienna 1900, The Free Press, 1991
Robin Tolmach Lakoff, James C. Coyne, Father Knows Best: The Use and Abuse of Power in Freud's Case of Dora, Teachers' College Press, 1993
Jeffrey Moussaieff Masson: Against Therapy (Chapter 2: Dora and Freud),
Patrick Mahoney, Freud's Dora: A Psychoanalytic, Historical, and Textual Study, Yale University Press 1996,
Gina Frangello, My Sister's Continent, Chiasmus Press, 2005
Dan Chapman, "Adorable White Bodies", a short story based on Freud's case, interpreting it from the perspective of Ida Bauer.
Dror Green, "Freud versus Dora and the transparent model of the case study", Modan Publishers, 1998.
Jody Shields, The Fig Eater: A Novel, centered around the murder of Dora, with a character based on Ida Bauer.
Film
Freud: The Secret Passion, director John Huston, 1962. Drama film with a heroine drawing from the Dora case.
Sigmund Freud’s Dora, directors Anthony McCall, Andrew Tyndall, Jane Weinstock, and Claire Pajaczkowska, 1979. Experimental essayistic film putting the Dora case into debates about psychoanalysis and feminism.
Nineteen Nineteen, director Hugh Brody, 1985. Dramatic fiction about a reunion of two patients of Freud, largely based on the Dora and Wolf-Man cases.
Hysterical Girl, 2020, director Kate Novack. A contemporary feminist interpretation of the study.
Stage
Portrait of Dora by Hélène Cixous, 1976
The Dark Sonnets of the Lady: A Drama in Two Acts, by Don Nigro, 1992.
Dora: A Case of Hysteria by Kim Morrissey, 1995
See also
References
Further reading
C. Bernheim/C. Kahane, In Dora's Case: Freud-Hysteria-Feminism (1985)
Mary Jacobus, Reading Woman (1986)
P. McCaffrey, Freud and Dora: The Artful Dream (1984)
Günter Rebing: Freuds Phantasiestücke. Die Fallgeschichten Dora, Hans, Rattenmann, Wolfsmann. Athena Verlag Oberhausen 2019, .
Anthony Stadlen, « Was Dora ill ? », in L. Spurling, dir., Sigmund Freud. Critical Assessments, vol. 1, London, Routledge, 1989, p. 196-203
External links
Jacques Lacan's interpretation of the Dora case - article on LacanOnline.com
Essay about Dora
Outline of the Case
Freud's Dora A Victorian Fable by Doug Davis
Freud exhibit which contains images of 'Dora'
1882 births
1945 deaths
19th-century Austrian Jews
20th-century Austrian Jews
19th-century Austrian women
20th-century Austrian women
Austrian Ashkenazi Jews
Dream
Analysands of Sigmund Freud
Case studies by Sigmund Freud
People from Vienna
Women and psychology
Hysteria | Dora (case study) | [
"Biology"
] | 2,657 | [
"Dream",
"Behavior",
"Sleep"
] |
4,129,530 | https://en.wikipedia.org/wiki/Dasymeter | A dasymeter was meant initially as a device to demonstrate the buoyant effect of gases like air (as shown in the adjacent pictures). A dasymeter which allows weighing acts as a densimeter used to measure the density of gases.
Principle
The Principle of Archimedes permits to derive a formula which does not rely on any information of volume: a sample, the big sphere in the adjacent images, of known mass-density is weighed in vacuum and then immersed into the gas and weighed again.
(The above formula was taken from the article buoyancy and still has to be solved for the density of the gas.)
From the known mass density of the sample (sphere) and its two weight-values, the mass-density of the gas can be calculated as:
Construction and use
It consists of a thin sphere made of glass, ideally with an average density close to that of the gas to be investigated. This sphere is immersed in the gas and weighed.
History of the dasymeter
The dasymeter was invented in 1650 by Otto von Guericke. Archimedes used a pair of scales which he immersed into water to demonstrate the buoyant effect of water. A dasymeter can be seen as a variant of that pair of scales, only immersed into gas.
References
External links
Volume Conversion
Measuring instruments
Laboratory equipment
Laboratory glassware | Dasymeter | [
"Technology",
"Engineering"
] | 276 | [
"Measuring instruments"
] |
4,129,776 | https://en.wikipedia.org/wiki/NGC%204027 | NGC 4027 (also known as Arp 22) is a barred spiral galaxy approximately 83 million light-years away in the constellation Corvus. It is also a peculiar galaxy because one of its spiral arms goes out more than the other. This is probably due to a galactic collision in NGC 4027's past.
One supernova has been observed in NGC 4027: SN 1996W (type II, mag. 16) was discovered by the BAO Supernova Survey on 10 April 1996.
Galaxy group information
NGC 4027 is part of the NGC 4038 Group, a group of galaxies that also contains the Antennae Galaxies (NGC 4038/NGC 4039).
See also
NGC 4618 - a similar one-armed spiral galaxy
NGC 4625 - a similar one-armed spiral galaxy
NGC 5713 - a similar one-armed spiral galaxy
References
External links
NGC 4027
The spiral galaxy NGC 4027
Barred spiral galaxies
Dwarf spiral galaxies
Magellanic spiral galaxies
Peculiar galaxies
NGC 4027
Corvus (constellation)
4027
37773
022
UGCA objects | NGC 4027 | [
"Astronomy"
] | 219 | [
"Corvus (constellation)",
"Constellations"
] |
4,129,884 | https://en.wikipedia.org/wiki/Eco-Schools | Eco-Schools is an international programme of the Foundation for Environmental Education (FEE) that aims to “empower students to be the change our sustainable world needs by engaging them in fun, action-orientated, and socially responsible learning.”
Each school follows a seven step change process and aims to “empowers young people to lead processes and actions wherever they can.”
Over time and through commitment to the Eco-Schools Seven Step process, improvements will be seen in both the learning outcomes, attitude, and behaviour of students and the local community, and ultimately the local environment. Evidence of success in these areas will eventually lead to a school being awarded with the International Green Flag.
Eco-Schools is one of the programmes recognised by the UN Decade of Education for Sustainable Development (2005 – 2014), awarding certificates to thousands of schools around the world.
The Eco-Schools programme extends from kindergartens to universities and is implemented in 67 countries, involving 51,000 schools and institutions, and over 19,000,000 students. It is the largest international network of teachers and students in the world. FEE EcoCampus is the name of the programme at university level.
History
The programme was developed in 1992 in response to the need to involve young people in environmental projects at the local level as identified at the United Nations Conference on Environment and Development of 1992.
Eco-Schools was launched in 1994 in Denmark, Germany, Greece and the United Kingdom with the support of the European Commission. When the Foundation for Environmental Education became global in 2001, countries outside of Europe began joining the Eco-Schools programme as well. South Africa was the first country to do so.
In 2003 Eco-Schools was identified by the United Nations Environment Programme (UNEP) as a model initiative for Education for Sustainable Development.
When countries joined Eco-Schools
Methodology
The International Eco-Schools Programme takes a holistic, participatory approach to learning for sustainability. The aim of the programme is to engage students through classroom study, school and community action to raise awareness of sustainable development issues. It encourages students and teachers to conduct research on the amount of waste, energy or water use at their school and work towards making it a more sustainable environment. Eco-Schools provides an integrated system for the environmental management of schools and involve all stakeholders in this process.
The whole schools approach embedded in the Eco-Schools programme emphasizes the importance of an ongoing focus on the issues linked to environmental, climate, and sustainability issues.
The programme's methodology consists of Seven Steps that the school needs to adopt:
Step 1 Establishment of the Eco-Schools Committee
Step 2 Environmental review
Step 3 Action Plan
Step 4 Monitoring and Evaluation
Step 5 Curriculum Linking
Step 6 Informing and involving the wider community
Step 7 Eco Code
Schools are encouraged to work on eleven Themes, which are as follows: Biodiversity & Nature, Climate Change, Energy, Global Citizenship, Health & Wellbeing, Litter, Marine and Coast, School Grounds, Transport, Waste, and Water.
Participation and awards
Any school may participate in the scheme by registering with the FEE member organisation in their country. Once registered, each school must review and improve their impact on the environment, and in recognition of their commitment and progress, they can then apply for an award.
Successful Eco-Schools are awarded the International Green Flag, an internationally acknowledged symbol for environmental excellence. In some countries, this recognition happens through a three level system, where schools are awarded either bronze and silver awards before receiving the International Green Flag.
There is flexibility to the ceremony and awarding process but the criteria for assessing schools for the award must follow the guidelines of FEE's International Eco-Schools programme.
Process
To qualify for an award the school must follow the following programme:
Register – usually done by an adult (teacher or parent).
Eco-Schools Committee – a group of pupils and adults – some elected by their peers are assembled to manage the process.
Environmental Review – the Eco-Schools Committee must organise the school to carry out a review of the school's energy and water usage, waste production and state of the school grounds with respect to litter.
Action Plan – formed from issues identified by the review
Eco Code – the Eco-Schools Committee, with the participation of the whole school must develop a mission statement to be prominently advertised inside and outside the school.
Link to Curriculum and Take Action – demonstrable progress must be made in three areas of the curriculum and involve as much of the school as possible.
Monitor and Review – the Eco-Schools Committee must record and analyse the progress made
After these processes are complete, the school can apply for one of the awards mentioned above, ultimately dependent on the level of environmental progress made.
FEE EcoCampus
The FEE EcoCampus programme is an evolution of the Eco-Schools programme. It targets students in third-level education in various countries and is implemented in the same way as Eco-Schools. The only real difference is that students devise an Eco Charter instead of an Eco Code.
This Charter is a document which is a guide to environmental management on site.
EcoCampus began in Russia in 2003 and the first whole institution Green Flags were awarded in Ireland in 2010, to University College Cork.
Eco-Schools Partners and Sponsors
United Nations Environment Programme (UNEP)
United Nations Educational, Scientific and Cultural Organization (UNESCO)
Earth Charter International
TheGoals.org
The Environmental Association for Universities and Colleges (EAUC)
The Global Action Programme (GAP) on Education for Sustainable Development
The Wrigley Company Foundation
Toyota Fund for Europe
eTwinning
Alcoa
Podio
Global Forest Fund
Eco-Schools compensates for their emissions from their flight travels when they go to, for example, conferences and National Operator Meetings through the Global Forest Fund. FEE has established the Global Forest Fund to help minimise the effects of emissions from the increased travel activity worldwide. The Fund supports schools and organisations by funding compensation efforts such as planting trees and environmental education activities.
Links
Eco-Schools is a programme of the Foundation for Environmental Education (FEE). FEE is a non-governmental, non-profit organisation promoting sustainable development through environmental education, and is active in five programmes; Blue Flag, Young Reporters for the Environment (YRE), Learning about Forests (LEAF), Green Key International and Eco-Schools.
FEE is an international umbrella organisation with members in 76 countries worldwide.
Research
Jelle Boeve-de Pauw & Peter Van Petegem (2017). Eco-school evaluation beyond labels: the impact of environmental policy, didactics and nature at school on student outcomes, Environmental Education Research, DOI: 10.1080/13504622.2017.1307327
HGSE Global Education Innovation Initiative Book 3: Case Studies from 50 Global Examples of Teaching and Learning in the 21st Century. Sowing the Seeds for an Ecologically Conscious Society: Foundation for Environmental Education (FEE) by Ashim Shanker and Connie K. Chung
ERIC ED497546: Evaluation of Eco-Schools Scotland. SCRE Research Report No. 124 at http://files.eric.ed.gov/fulltext/ED497546.pdf
Sibel Ozsoy, Hamide Ertepinar and Necdet Saglam (2012). Can eco-schools improve elementary school students’ environmental literacy levels? in Asia-Pacific Forum on Science Learning and Teaching, Volume 13, Issue 2, Article 3
References
Sharma, P.K., Anderou, N., Funder A. C.. D, Changing Together - Eco-Schools (1994-2019), (2019) Foundation for Environmental Education
retrieved from https://www.academia.edu/41661936/Changing_Together_Eco_Schools_1994_2019_
External links
Eco-Schools
Environmental education
Environmentalism
International environmental organizations
Schools programs | Eco-Schools | [
"Environmental_science"
] | 1,574 | [
"Environmental education",
"Environmental social science"
] |
4,129,998 | https://en.wikipedia.org/wiki/Whittington%20chimes | Whittington chimes, also called St. Mary's, are a family of clock chime melodies associated with St Mary-le-Bow church in London, which is related to the historical figure of Whittington by legend.
Whittington is usually the secondary chime selection for most chiming clocks, the first being the Westminster. It is also one of two clock chime melodies with multiple variations, the other being the Ave Maria chimes.
Before the name Whittington became common, the melody used to be referred to as “chimes on eight bells”. However, evidence suggests it was originally a chime on six bells – a melody that has not been in use at St Mary-le-Bow since 1666. In 1905, based on what was known about the six-bell version, Sir Charles Villiers Stanford composed a new melody (still called Whittington chimes) that uses 11 out of the 12 bells in the tower of St Mary-le-Bow; this 11-bell version is the one now used at that church.
Dick Whittington story
The customary English theatre story, adapted from the life of the real Richard Whittington, is that the young boy Dick Whittington was an unhappy apprentice running away from his master, and heard the tune ringing from the bell tower of the church of St Mary-le-Bow in London in 1392. The penniless boy heard the bells seemingly saying to him "Turn again Dick Whittington". Dick returned to London upon hearing the bells, where he went on to find his fortune and became the Lord Mayor of London four times.
According to tradition, Whittington used the tune as a campaign song for his three returns to the office of mayor. A short version of the campaign song goes:
Turn again Dick Whittington,
Right Lord Mayor of London Town.
Chimes of St Mary-le-Bow
The twelve bells in the tower of St Mary-le-Bow, cast in 1956, all have inscriptions on them; the first letters of each inscription spell out:
D W H I T T I N G T O N
Chimes on domestic clocks
The Whittington chimes are less well known than the Westminster (Cambridge) chimes, despite being much older. The chimes are found in many early English bracket and longcase clocks. The melody was not given the name "Whittington Chimes" on domestic clocks until the late Victorian period onwards.
Whittington chimes found on domestic clocks are variations on the eight-bell melody, and there are at least four variations of this chime sequence. Currently the Whittington chime is often available on grandfather clock movements that have selectable chimes and some quartz clocks.
Bawo & Dotter Chimes
One of the Whittington chime variations is also known as the Bawo & Dotter chimes, and is usually found on many older German movements such as early models of Junghans grandfather clocks. This version of the chimes is remarkably different and unique from the other three variations; only the first-quarter melody remains the same with the other variations.
References
Clocks
Anonymous musical compositions
Compositions by Charles Villiers Stanford | Whittington chimes | [
"Physics",
"Technology",
"Engineering"
] | 663 | [
"Physical systems",
"Machines",
"Clocks",
"Measuring instruments"
] |
4,130,473 | https://en.wikipedia.org/wiki/143P/Kowal%E2%80%93Mrkos | 143P/Kowal–Mrkos is a periodic comet in the Solar System.
References
External links
143P/Kowal-Mrkos – Seiichi Yoshida @ aerith.net
143P at Kronk's Cometography
Periodic comets
0143
143P
Discoveries by Charles T. Kowal
143P
19840423 | 143P/Kowal–Mrkos | [
"Astronomy"
] | 70 | [
"Recovered astronomical objects",
"Astronomical objects"
] |
4,130,512 | https://en.wikipedia.org/wiki/HD%2010307 | HD 10307 (HR 483) is a spectroscopic binary star in the constellation Andromeda. The primary is similar to the Sun in mass, temperature and metal content. It is situated about 42 light-years from Earth. Its companion, HR 483 B, is a little-studied red dwarf.
HD 10307 was identified in September 2003 by astrobiologist Margaret Turnbull from the University of Arizona in Tucson as one of the most promising nearby candidates for hosting life based on her analysis of the HabCat list of stars.
System
HR 483 is a binary located 42.6 ly away, in Andromeda. The two stars orbit one another elliptically (e=0.44), approaching as close as 4.2 AU and receding to 10.5 AU, with a period of just under twenty years.
HD 10307 A, the larger component, is a G-type main-sequence star similar to the Sun, only slightly brighter, hotter, larger, and older than the Sun—though with a slightly smaller mass. It has a low level of activity and is a candidate Maunder minimum analog. HR 483 B, the smaller component, appears to be a red dwarf, with as little as thirty-eight percent the mass of the sun. A debris disk has been detected in this system.
The presence of a moderately close companion could disrupt the orbit of a hypothetical planet in HD 10307's habitable zone. However, the uncertainty of the orbital parameters makes it equally uncertain exactly where stable orbits would be in this system.
METI message to HD 10307
There was a METI message sent to HD 10307. It was transmitted from Eurasia's largest radar, 70-meter Eupatoria Planetary Radar. The message was named Cosmic Call 2, it was sent on July 6, 2003, and it will arrive at HD 10307 in September 2044.
References
External links
High proper-motion Star
Image HD 10307
Space.com: Top 10 List of Habitable Stars to Guide Search
Spectra HD 10307
G-type main-sequence stars
M-type main-sequence stars
Solar analogs
Maunder Minimum
Spectroscopic binaries
Andromeda (constellation)
Durchmusterung objects
010307
0067
007918
0483 | HD 10307 | [
"Astronomy"
] | 480 | [
"Maunder Minimum",
"Magnetism in astronomy",
"Andromeda (constellation)",
"Constellations"
] |
11,798,914 | https://en.wikipedia.org/wiki/Phyllachora%20graminis | Phyllachora graminis is a plant pathogen infecting wheat.
References
External links
Index Fungorum
USDA ARS Fungal Database
Fungal plant pathogens and diseases
Wheat diseases
Phyllachorales
Taxa named by Christiaan Hendrik Persoon
Fungus species | Phyllachora graminis | [
"Biology"
] | 57 | [
"Fungi",
"Fungus species"
] |
11,799,822 | https://en.wikipedia.org/wiki/Wang%20Institute%20of%20Graduate%20Studies | The Wang Institute of Graduate Studies was an independent educational institution founded in 1979 by computer entrepreneur An Wang. Its purpose was to provide professional and continuing studies in the nascent field of software engineering. It was accredited by the New England Association of Schools and Colleges in 1983. Faculty members were recruited from industry and students were required to have a minimum of three years prior experience in industry as a condition of acceptance.
The Institute acquired its campus from the Marist Brothers who had operated a seminary on the site since 1924. Located in Tyngsborough, Massachusetts, it housed two divisions: The School of Information Technology and a fellowship program in East Asian studies.
The Institute never grew beyond a dozen or so faculty. As a result of declining business fortunes Dr. Wang closed the Institute, graduating the last class on August 27, 1988. The campus was transferred to Boston University where it served as a corporate education center. Today, it is the location of the Innovation Academy Charter School.
Software engineering curriculum
The Institute graduated seven classes between 1982 and 1988 in its Master of Software Engineering program, requiring study in eleven three-credit courses. Two project courses involved students in team-based analysis, specification, design, implementation, testing, and integration of software products.Fairley, Richard and Martin, Nancy. "Software engineering programs at the Wang Institute of Graduate Studies," Proceedings of the 1983 annual conference on Computers (1983)
The original six core courses were:
The curriculum was later modified to include an optional operating systems course instead of the architecture course.Ardis, Mark. "The Evolution of Wang Institute's Master of Software Engineering Program," IEEE Transactions on Software Engineering 13(11), 1149-1155, November (1987).
Elective courses covered a wide spectrum of computer science and management topics, including: compiler construction, database management systems, decision support systems, expert system technology, principles of computer networks, programming environments, requirements analysis, software marketing, technical communication, transaction processing systems, user interface design, and validation and verification.
Notes
Defunct private universities and colleges in Massachusetts
Educational institutions established in 1979
Software engineering organizations
Educational institutions disestablished in 1988
1979 establishments in Massachusetts | Wang Institute of Graduate Studies | [
"Engineering"
] | 436 | [
"Software engineering",
"Software engineering organizations"
] |
11,799,986 | https://en.wikipedia.org/wiki/Colletotrichum%20mangenotii | Colletotrichum mangenotii is a fungal plant pathogen.
References
mangenotii
Fungal plant pathogens and diseases
Fungi described in 1952
Fungus species | Colletotrichum mangenotii | [
"Biology"
] | 34 | [
"Fungi",
"Fungus species"
] |
11,800,151 | https://en.wikipedia.org/wiki/Gymnosporangium%20sabinae | Gymnosporangium sabinae is a species of rust fungus in the subdivision Pucciniomycotina. Known as pear rust, European pear rust, or pear trellis rust, it is a heteroecious plant pathogen with Juniperus sabina (savin juniper) as the main primary (telial) host and Pyrus communis (common pear) as the main secondary (aecial) host.
Life cycle
Like many rusts, G. sabinae requires two different hosts to complete its life cycle from year to year. Juniper is the winter host and pear is the summer host. Spores (called aeciospores) are produced from the fungal lantern-shaped growths which protrude from the blisters on the underside of the pear leaf which become airborne and infect junipers. This fungus overwinters in swellings or galls on infected twigs and branches of susceptible juniper plants. In the spring after a rain or heavy dew, the galls on the juniper produce tiny dark horn-like growths that become covered with an orange-brown gelatinous mass called telia. The corresponding stage on the pear trees is known as aecia. The telia and aecia release wind borne resting or hibernating spores (called teliospores and aeciospores) capable of infecting susceptible pear leaves and Juniper respectively. Spores produced from the fungus-induced swellings on juniper stems can be infectious up to 6 km. The disease causes a yellow-orange spot that turns bright red on leaves of pear trees. The disease can be particularly damaging on pear, resulting in complete defoliation and crop loss if not treated. The fungus feeds on the living cells of the host plant and is not capable of surviving on dead plant material, and so must either alternate with a different host or produce resting spores to pass the dormant season.
Hosts and distribution
Juniperus sabina (savin juniper) is the main primary (telial) host, but G. sabinae also occurs on Juniperus chinensis and other species in Juniperus sect. Sabinae. The north European Juniperus communis (common juniper) is not a host. The main secondary (aecial) host is Pyrus communis (common pear), but other pear species, such as the ornamental Pyrus calleryana (Bradford pear), are also susceptible.
The native distribution of Gymnosporangium sabinae follows that of Juniperus sabina, a montane shrub with a range extending from southern Europe and the Alps into North Africa and Asia, and Pyrus communis (common pear) with a native range in continental Europe, the Middle East, and western Asia. The fungus has, however, extended its range in Europe as far north as Scandinavia and the British Isles through the frequent use of savin and other junipers as ornamental garden shrubs. Gymnosporangium sabinae has also been reported from North America. Pear rust is a regulated disease in some countries.
Control
Pruning out any infected juniper twigs and branches in winter and early spring can help reduce the spread of G. sabinae. The vulnerable point of the fungus lies in its usual inability once established on a tree to reinfect it. Generally, the fungus must cross over to the opposite tree host. The most direct method of control is to exterminate juniper hosts near pear trees, though spores can travel at least 6 km from one host to another. If there is a chance of infection, spraying pear trees with a fungicide in spring and summer (typically a systemic one that is certified as capable of dealing with rust) may help, although this is often not considered worthwhile.
References
Fungi described in 1785
Fungi of Europe
Fungi of Asia
Fungi of Africa
Fungi of North America
Fungal tree pathogens and diseases
Pear tree diseases
Pucciniales
Taxa named by James Dickson (botanist)
Fungus species | Gymnosporangium sabinae | [
"Biology"
] | 801 | [
"Fungi",
"Fungus species"
] |
11,800,289 | https://en.wikipedia.org/wiki/Moesziomyces%20bullatus | Moesziomyces bullatus is a fungal plant pathogen.
References
External links
Index Fungorum
USDA ARS Fungal Database
Fungal plant pathogens and diseases
Ustilaginomycotina
Taxa named by Joseph Schröter
Fungus species | Moesziomyces bullatus | [
"Biology"
] | 49 | [
"Fungi",
"Fungus species"
] |
11,800,340 | https://en.wikipedia.org/wiki/Colletotrichum%20pisi | Colletotrichum pisi is a plant pathogen.
References
pisi
Fungal plant pathogens and diseases
Fungi described in 1891
Fungus species | Colletotrichum pisi | [
"Biology"
] | 29 | [
"Fungi",
"Fungus species"
] |
11,800,426 | https://en.wikipedia.org/wiki/Cercospora%20fusca | Cercospora fusca is a fungal plant pathogen.
References
fusca
Fungal plant pathogens and diseases
Fungus species | Cercospora fusca | [
"Biology"
] | 25 | [
"Fungi",
"Fungus species"
] |
11,800,442 | https://en.wikipedia.org/wiki/Clitocybe%20parasitica | Clitocybe parasitica is classified as a plant pathogen, because in the United States it causes Clitocybe Root Rot, affecting apple, peach, cherry, and oak species. First detected in Oklahoma in 1900 and described by E.M. Wilcox the following year, C. parasitica has been found afflicting orchard trees as far north as Oregon.
References
External links
Index Fungorum
USDA ARS Fungal Database
Fungal plant pathogens and diseases
parasitica
Fungus species | Clitocybe parasitica | [
"Biology"
] | 98 | [
"Fungi",
"Fungus species"
] |
11,800,476 | https://en.wikipedia.org/wiki/Cercospora%20halstedii | Cercospora halstedii is a fungal plant pathogen.
References
halstedii
Fungal plant pathogens and diseases
Taxa named by Benjamin Matlack Everhart
Fungi described in 1891
Fungus species | Cercospora halstedii | [
"Biology"
] | 40 | [
"Fungi",
"Fungus species"
] |
11,801,199 | https://en.wikipedia.org/wiki/Zero%20field%20NMR | Zero- to ultralow-field (ZULF) NMR is the acquisition of nuclear magnetic resonance (NMR) spectra of chemicals with magnetically active nuclei (spins 1/2 and greater) in an environment carefully screened from magnetic fields (including from the Earth's field). ZULF NMR experiments typically involve the use of passive or active shielding to attenuate Earth’s magnetic field. This is in contrast to the majority of NMR experiments which are performed in high magnetic fields provided by superconducting magnets. In ZULF experiments the sample is moved through a low field magnet into the "zero field" region where the dominant interactions are nuclear spin-spin couplings, and the coupling between spins and the external magnetic field is a perturbation to this. There are a number of advantages to operating in this regime: magnetic-susceptibility-induced line broadening is attenuated which reduces inhomogeneous broadening of the spectral lines for samples in heterogeneous environments. Another advantage is that the low frequency signals readily pass through conductive materials such as metals due to the increased skin depth; this is not the case for high-field NMR for which the sample containers are usually made of glass, quartz or ceramic.
High-field NMR employs inductive detectors to pick up the radiofrequency signals, but this would be inefficient in ZULF NMR experiments since the signal frequencies are typically much lower (on the order of hertz to kilohertz). The development of highly sensitive magnetic sensors in the early 2000s including SQUIDs, magnetoresistive sensors, and SERF atomic magnetometers made it possible to detect NMR signals directly in the ZULF regime. Previous ZULF NMR experiments relied on indirect detection where the sample had to be shuttled from the shielded ZULF environment into a high magnetic field for detection with a conventional inductive pick-up coil. One successful implementation was using atomic magnetometers at zero magnetic field working with rubidium vapor cells to detect zero-field NMR.
Without a large magnetic field to induce nuclear spin polarization, the nuclear spins must be polarized externally using hyperpolarization techniques. This can be as simple as polarizing the spins in a magnetic field followed by shuttling to the ZULF region for signal acquisition, and alternative chemistry-based hyperpolarization techniques can also be used.
It is sometimes but inaccurately referred to as nuclear quadrupole resonance (NQR).
Zero-field NMR experiments
Spin Hamiltonians
Free evolution of nuclear spins is governed by a Hamiltonian (), which in the case of liquid-state nuclear magnetic resonance may be split into two major terms. The first term () corresponds to the Zeeman interaction between spins and the external magnetic field, which includes chemical shift (). The second term () corresponds to the indirect spin-spin, or J-coupling, interaction.
, where:
, and
.
Here the summation is taken over the whole system of coupled spins; denotes the reduced Planck constant; denotes the gyromagnetic ratio of spin a; denotes the isotropic part of the chemical shift for the a-th spin; denotes the spin operator of the a-th spin; is the external magnetic field experienced by all considered spins, and; is the J-coupling constant between spins a and b.
Importantly, the relative strength of and (and therefore the spin dynamics behavior of such a system) depends on the magnetic field. For example, in conventional NMR, is typically larger than 1 T, so the Larmor frequency of 1H exceeds tens of MHz. This is much larger than -coupling values which are typically Hz to hundreds of Hz. In this limit, is a perturbation to . In contrast, at nanotesla fields, Larmor frequencies can be much smaller than -couplings, and dominates.
Polarization
Before signals can be detected in a ZULF NMR experiment, it is first necessary to polarize the nuclear spin ensemble, since the signal is proportional to the nuclear spin magnetization. There are a number of methods to generate nuclear spin polarization. The most common is to allow the spins to thermally equilibrate in a magnetic field, and the nuclear spin alignment with the magnetic field due to the Zeeman interaction leads to weak spin polarization. The polarization generated in this way is on the order of 10−6 for tesla field-strengths.
An alternative approach is to use hyperpolarization techniques, which are chemical and physical methods to generate nuclear spin polarization. Examples include parahydrogen-induced polarization, spin-exchange optical pumping of noble gas atoms, dissolution dynamic nuclear polarization, and chemically-induced dynamic nuclear polarization.
Excitation and spin manipulation
NMR experiments require creating a transient non-stationary state of the spin system. In conventional high-field experiments, radio frequency pulses tilt the magnetization from along the main magnetic field direction to the transverse plan. Once in the transverse plan, the magnetization is no longer in a stationary state (or eigenstate) and so it begins to precess about the main magnetic field creating a detectable oscillating magnetic field.
In ZULF experiments, constant magnetic field pulses are used to induce non-stationary states of the spin system. The two main strategies consist of (1) switching of the magnetic field from pseudo-high field to zero (or ultra-low) field, or (2) of ramping down the magnetic field experienced by the spins to zero field in order to convert the Zeeman populations into zero-field eigenstates adiabatically and subsequently in applying a constant magnetic field pulse to induce a coherence between the zero-field eigenstates. In the simple case of a heteronuclear pair of J-coupled spins, both these excitation schemes induce a transition between the singlet and triplet-0 states, which generates a detectable oscillatory magnetic field.
More sophisticated pulse sequences have been reported including selective pulses, two-dimensional experiments and decoupling schemes.
Signal detection
NMR signals are usually detected inductively, but the low frequencies of the electromagnetic radiation emitted by samples in a ZULF experiment makes inductive detection impractical at low fields. Hence, the earliest approach for measuring zero-field NMR in solid samples was via field-cycling techniques. The field cycling involves three steps: preparation, evolution and detection. In the preparation stage, a field is applied in order to magnetize the nuclear spins. Then the field is suddenly switched to zero to initiate the evolution interval and the magnetization evolves under the zero-field Hamiltonian. After a time period, the field is again switched on and the signal is detected inductively at high field. In a single field cycle, the magnetization observed corresponds only to a single value of the zero-field evolution time. The time-varying magnetization can be detected by repeating the field cycle with incremented lengths of the zero-field interval, and hence the evolution and decay of the magnetization is measured point by point. The Fourier transform of this magnetization will result to the zero-field absorption spectrum.
The emergence of highly sensitive magnetometry techniques has allowed for the detection of zero-field NMR signals in situ. Examples include superconducting quantum interference devices (SQUIDs), magnetoresistive sensors, and SERF atomic magnetometers. SQUIDs have high sensitivity, but require cryogenic conditions to operate, which makes them practically somewhat difficult to employ for the detection of chemical or biological samples. Magnetoresistive sensors are less sensitive, but are much easier to handle and to bring close to the NMR sample which is advantageous since proximity improves sensitivity. The most common sensors employed in ZULF NMR experiments are optically-pumped magnetometers, which have high sensitivity and can be placed in close proximity to an NMR sample.
Definition of the ZULF regime
The boundaries between zero-, ultralow-, low- and high-field NMR are not rigorously defined, although approximate working definitions are in routine use for experiments involving small molecules in solution. The boundary between zero and ultralow field is usually defined as the field at which the nuclear spin precession frequency matches the spin relaxation rate, i.e., at zero field the nuclear spins relax faster than they precess about the external field. The boundary between ultralow and low field is usually defined as the field at which Larmor frequency differences between different nuclear spin species match the spin-spin (J or dipolar) couplings, i.e., at ultralow field spin-spin couplings dominate and the Zeeman interaction is a perturbation. The boundary between low and high field is more ambiguous and these terms are used differently depending on the application or research topic. In the context of ZULF NMR, the boundary is defined as the field at which chemical shift differences between nuclei of the same isotopic species in a sample match the spin-spin couplings.
Note that these definitions strongly depend on the sample being studied, and the field regime boundaries can vary by orders of magnitude depending on sample parameters such as the nuclear spin species, spin-spin coupling strengths, and spin relaxation times.
See also
Earth's field NMR
Low field NMR
References
Further reading
M. P. Ledbetter, C. Crawford, A. Pines, D. Wemmer, S. Knappe, J. Kitching, D. Budker "Optical detection of NMR J-spectra at zero magnetic field" J. Magn. Reson. (2009), 199, 25-29.
T. Theis, P. Ganssle, G. Kervern, S. Knappe, J. Kitching, M. P. Ledbetter, D. Budker and A. Pines; “Parahydrogen-enhanced zero-field nuclear magnetic resonance” Nature Physics (2011), 7, 571–575.
External links
https://pines.berkeley.edu/research/ultra-low-field-zero-field-nmr
https://pines.berkeley.edu/publications/chemical-analysis-using-j-coupling-multiplets-zero-field-nmr-0
Nuclear magnetic resonance | Zero field NMR | [
"Physics",
"Chemistry"
] | 2,133 | [
"Nuclear magnetic resonance",
"Nuclear physics"
] |
11,801,329 | https://en.wikipedia.org/wiki/KR580VM80A | The KR580VM80A () is a Soviet microprocessor, a clone of the Intel 8080 CPU. Different versions of this CPU were manufactured beginning in the late 1970s, the earliest known use being in the SM1800 computer in 1979. Initially called the K580IK80 (К580ИК80), it was produced in a 48-pin planar metal-ceramic package. Later, a version in a PDIP-40 package was produced and was named the KR580IK80A (КР580ИК80А). The pin layout of the latter completely matched that of Intel's 8080A CPU. In 1986 this CPU received a new part number to conform with the 1980 Soviet integrated circuit designation and became known as the KR580VM80A (КР580ВМ80А), the number it is most widely known by today (the KR580VV51A and KR580VV55A peripheral devices went through similar revisions). Normal clock frequency for the K580IK80A is 2 MHz, with speeds up to 2.5 MHz for the KR580VM80A. The KR580IK80A was manufactured in a 6 μm process. In the later KR580VM80A the feature size was reduced to 5 μm and the die became 20% smaller.
Technology and support chips
The KR580VM80A was manufactured with an n-MOS process. The pins were electrically compatible with TTL logic levels. The load capacity of each output pin was sufficient for one TTL input. The output capacitance of each control and data pins was ≤ 100pF each.
The family consists of the following chips:
For brevity, the table above lists only the chip variants in a plastic DIP (prefix КР) as well as the original planar package (prefix К). Not listed separately are variants in a ceramic DIP (prefix КМ for commercial version and prefix М or no prefix for the military version) or export variants (prefix ЭКР) in a plastic DIP but with a pin spacing of one tenth of an inch.
For the KR580VM1 (КР580ВМ1) see Further development below.
Several integrated circuits in the K580 series were actually intended for other microprocessor families: the KR580VR43 (КР580ВР43 — Intel 8243) for the K1816 family (Intel MCS-48) and the KR580GF84 (КР580ГФ84 — Intel 8284) / KR580VG88 (КР580ВГ88 — Intel 8288) / KR580VB89 (КР580ВБ89 — Intel 8289) for the K1810 family (Intel 8086). Additionally, most devices in the K580 series could be used for the K1810 series as well.
KR580VM80A vs. Intel 8080A
While the Soviet clone appears to be fully software-compatible with Intel 8080A, there is a slight difference between the two processors' interrupt handling logic, which looks like an error in the KR580VM80A's microcode. If a CALL instruction opcode is supplied during INTA cycle and the INT input remains asserted, the KR580VM80A does not clear its internal Interrupt Enable flag, despite the INTE output going inactive. As a result, the CPU enters a microcode loop, continuously acknowledging the interrupt and pushing the PC onto the stack, which leads to stack overflow. In a typical hardware configuration this phenomenon is masked by the behavior of 8259A interrupt controller, which deasserts INT during INTA cycle. The Romanian MMN8080 behaves the same as the KR580VM80A; no other 8080A clones seem to be affected by this error.
Applications
The KR580VM80A was popular in home computers, computer terminals, industrial controllers. Some of the examples of its successful application are:
KUVT Korvet educational computer
Radio-86RK (Радио 86РК), probably the most popular amateur single-board computer in the Soviet Union
Micro-80 (Микро-80 in Russian), Radio 86RK's predecessor
Orion-128 (Орион-128 in Russian), Radio 86RK's successor, which had a graphical display
Specialist (computer), similar to Orion-128
UT-88 amateur computer
SM 1800 industrial mini computer
Vector-06C home computer, where KR580VM80A is overclocked to 3 MHz by design
TIA-MC-1 (ТИА-МЦ-1) arcade machine
Juku E5101 educational computer designed in Estonia
Maestro (Маэстро) Soviet four voice hybrid analog synthesizer keyboard
Further development
Mirroring the development in the West, where the Intel 8080 was succeeded by the binary compatible Intel 8085 and Zilog Z80 as well as the source compatible Intel 8086, the Soviet Union produced the IM1821VM85A (ИМ1821ВМ85А, actually the CMOS version Intel 80C85), KR1858VM1 (КР1858ВМ1), and K1810VM86 (К1810ВМ86), respectively. The 580VM80 is still shown on the price list of 15 August 2022 of the "Kvazar" plant in Kyiv together with various support chips of the K580 series.
Another development, the KR580VM1 (КР580ВМ1), has no western equivalent. The KR580VM1 extends the Intel 8080 architecture and is binary compatible with it. The extensions differ, however, from both the Intel 8085 and the Zilog Z80. The KR580VM1 extends the address range from 64KB to 128KB. It adds two registers, H1 and L1, that can be used instead of H and L. Several 16-bit arithmetic instructions were added as well (DAD, DSUB, DCOMP). Just like the Intel 8085 and the Zilog Z80, the KR580VM1 needs only a single +5V power supply instead of the three voltages required by the KR580VM80A. The maximum clock frequency was increased from 2 MHz to 5 MHz while the power consumption was reduced from 1.35W to 0.5W, compared to the KR580VM80A.
See also
Intel 8080
MCS-85 Family
List of Soviet computer systems
Soviet integrated circuit designation
References
External links
CPU World page about KR580VM80A
Reverse-engineering of KR580VM80A
Computer-related introductions in 1979
Computing in the Soviet Union
8-bit microprocessors | KR580VM80A | [
"Technology"
] | 1,485 | [
"Computing in the Soviet Union",
"History of computing"
] |
11,801,835 | https://en.wikipedia.org/wiki/Kin%20recognition | Kin recognition, also called kin detection, is an organism's ability to distinguish between close genetic kin and non-kin. In evolutionary biology and psychology, such an ability is presumed to have evolved for inbreeding avoidance, though animals do not typically avoid inbreeding.
An additional adaptive function sometimes posited for kin recognition is a role in kin selection. There is debate over this, since in strict theoretical terms kin recognition is not necessary for kin selection or the cooperation associated with it. Rather, social behaviour can emerge by kin selection in the demographic conditions of 'viscous populations' with organisms interacting in their natal context, without active kin discrimination, since social participants by default typically share recent common origin. Since kin selection theory emerged, much research has been produced investigating the possible role of kin recognition mechanisms in mediating altruism. Taken as a whole, this research suggests that active powers of recognition play a negligible role in mediating social cooperation relative to less elaborate cue-based and context-based mechanisms, such as familiarity, imprinting and phenotype matching.
Because cue-based 'recognition' predominates in social mammals, outcomes are non-deterministic in relation to actual genetic kinship, instead outcomes simply reliably correlate with genetic kinship in an organism's typical conditions. A well-known human example of an inbreeding avoidance mechanism is the Westermarck effect, in which unrelated individuals who happen to spend their childhood in the same household find each other sexually unattractive. Similarly, due to the cue-based mechanisms that mediate social bonding and cooperation, unrelated individuals who grow up together in this way are also likely to demonstrate strong social and emotional ties, and enduring altruism.
Theoretical background
The English evolutionary biologist W. D. Hamilton's theory of inclusive fitness, and the related theory of kin selection, were formalized in the 1960s and 1970s to explain the evolution of social behaviours. Hamilton's early papers, as well as giving a mathematical account of the selection pressure, discussed possible implications and behavioural manifestations. Hamilton considered potential roles of cue-based mechanisms mediating altruism versus 'positive powers' of kin discrimination:
These two possibilities, altruism mediated via 'passive situation' or via 'sophisticated discrimination', stimulated a generation of researchers to look for evidence of any 'sophisticated' kin discrimination. However, Hamilton later (1987) developed his thinking to consider that "an innate kin recognition adaptation" was unlikely to play a role in mediating altruistic behaviours:
The implication that the inclusive fitness criterion can be met by mediating mechanisms of cooperative behaviour that are context and location-based has been clarified by recent work by West et al.:
For a recent review of the debates around kin recognition and their role in the wider debates about how to interpret inclusive fitness theory, including its compatibility with ethnographic data on human kinship, see Holland (2012).
Criticism
Leading inclusive fitness theorists such as Alan Grafen have argued that the whole research program around kin recognition is somewhat misguided:
Others have cast similar doubts over the enterprise:
Experimental evidence
Kin recognition is a behavioral adaptation noted in many species but proximate level mechanisms are not well documented. Recent studies have shown that kin recognition can result from a multitude of sensory input. Jill Mateo notes that there are three components prominent in kin recognition. First, "production of unique phenotypic cues or labels". Second, "perception of these labels and the degree of correspondence of these labels with a 'recognition template'", and finally the recognition of the phenotypes should lead to "action taken by the animal as a function of the perceived similarity between its template and an encountered phenotype".
The three components allow for several possible mechanisms of kin recognition. Sensory information gathered from visual, olfactory and auditory stimuli are the most prevalent. The Belding's ground squirrel kin produce similar odors in comparison to non-kin. Mateo notes that the squirrels spent longer investigating non-kin scents suggesting recognition of kin odor. It's also noted that Belding's ground squirrels produce at least two scents arising from dorsal and oral secretions, giving two opportunities for kin recognition. In addition, the Black Rock Skink is also able to use olfactory stimuli as a mechanism of kin recognition. Egernia saxatilis have been found to discriminate kin from non-kin based on scent. Egernia striolata also use some form of scent, most likely through skin secretions. However, Black Rock Skinks discriminate based on familiarity rather than genotypic similarity. Juvenile E. saxatilis can recognize the difference between the scent of adults from their own family group and unrelated adults. Black Rock Skink recognize their family groups based on prior association and not how genetically related the other lizards are to themselves. Auditory distinctions have been noted among avian species. Long-tailed tits (Aegithalos caudatus) are capable of discriminating kin and non-kin based on contact calls. Distinguishing calls are often learned from adults during the nestling period. Studies suggest that the bald-faced hornet, Dolichovespula maculata, can recognize nest mates by their cuticular hydrocarbon profile, which produces a distinct smell.
Kin recognition in some species may also be mediated by immunogenetic similarity of the major histocompatibility complex (MHC). For a discussion of the interaction of these social and biological kin recognition factors see Lieberman, Tooby, and Cosmides (2007). Some have suggested that, as applied to humans, this nature-nurture interactionist perspective allows a synthesis between theories and evidence of social bonding and cooperation across the fields of evolutionary biology, psychology (attachment theory) and cultural anthropology (nurture kinship).
A study has shown that humans are about as genetically equivalent to their friends as they are their fourth cousins.
In Plants
Kin recognition is an adaptive behavior observed in living beings to prevent inbreeding, and increase fitness of populations, individuals and genes. Kin recognition is the key to successful reciprocal altruism, a behavior that increases reproductive success of both organisms involved. Reciprocal altruism as a product of kin recognition has been observed and studied in many animals, and more recently, plants. Due to the nature of plant reproduction and growth, plants are more likely than animals to live in close proximity to family members, and therefore stand to gain more from the ability to differentiate kin from strangers.
In recent years, botanists have been conducting studies to determine which plant species can recognize kin, and discover the responses of plants to neighboring kin. Murphy and Dudley (2009) shows that Impatiens pallida has the ability to recognize individuals closely related to them and those not related to them. The physiological response to this recognition is increasingly interesting. I. pallida responds to kin by increasing branchiness and stem elongation, to prevent shading relatives, and responds to strangers by increasing leaf to root allocation, as a form of competition.
Root allocation has been a very common trait shown through research in plants. Limited amounts of biomass can cause trade-offs among the construction of leaves, stems, and roots overall. But, in plants that recognize kin, the movement of resources in the plant has been shown to be affected by proximity to related individuals. It is well documented that roots can emit volatile compounds in the soil and that interactions also occur below-ground between plant roots and soil organisms. This has mainly focused on organisms in the kingdom Animalia, however.
Regarding this, root systems are known to exchange carbon and defense related molecular signals via connected mycorrhizal networks. For instance, it has been demonstrated that tobacco plants can detect the volatile chemical ethylene in order to form a “shade-avoidance phenotype.” Barley plants were also shown to allocate biomass to their roots when exposed to chemical signals from members of the same species, showing that, if they can recognize those signals for competition, recognition of kin in the plant could be likely via a similar chemical response.
Similarly, Bhatt et al. (2010) show that Cakile edentula, the American sea rocket, has the ability to allocate more energy to root growth, and competition, in response to growing next to a stranger, and allocates less energy to root growth when planted next to a sibling. This reduces competition between siblings and increases fitness of relatives growing next to each other, while still allowing competition between non-relative plants.
Little is known about the mechanisms involved in kin recognition. They most likely vary between species as well as within species. A study by Bierdrzycki et al. (2010) shows that root secretions are necessary for Arabidopsis thaliana to recognize kin vs. strangers, but not necessary to recognize self vs. non-self roots. This study was performed using secretion inhibitors, which disabled the mechanism responsible for kin recognition in this species, and showed similar growth patterns to Bhatt et al., (2010) and Murphy and Dudley (2009) in control groups. The most interesting result of this study was that inhibiting root secretions did not reduce the ability of Arabidopsis to recognize their own roots, which implicates a separate mechanism for self/non-self recognition than that for kin/stranger recognition.
While this mechanism in the roots responds to exudates and involves competition over resources like nitrogen and phosphorus, another mechanism has been recently proposed, which involves competition over light, in which kin recognition takes place in leaves. In their 2014 study, Crepy and Casal conducted multiple experiments on different accessions of A. thaliana. These experiments showed that Arabidopsis accessions have distinct R:FR and blue light signatures, and that these signatures can be detected by photoreceptors, which allows the plant to recognize its neighbor as a relative or non-relative. Not much is known about the pathway that Arabidopsis uses to associate these light patterns with kin, however, researchers ascertained that photoreceptors phyB, cry 1, cry 2, phot1, and phot2 are involved in the process by performing a series of experiments with knock-out mutants. Researchers also concluded that the auxin-synthesis gene TAA1 is involved in the process, downstream of the photoreceptors, by performing a similar experiments using Sav3 knock-out mutants. This mechanism leads to altered leaf direction to prevent shading of related neighbors and to reduce competition for sunlight.
Inbreeding avoidance
When mice inbreed with close relatives in their natural habitat, there is a significant detrimental effect on progeny survival. Since inbreeding can be detrimental, it tends to be avoided by many species. In the house mouse, the major urinary protein (MUP) gene cluster provides a highly polymorphic scent signal of genetic identity that appears to underlie kin recognition and inbreeding avoidance. Thus there are fewer matings between mice sharing MUP haplotypes than would be expected if there were random mating. Another mechanism for avoiding inbreeding is evident when a female house mouse mates with multiple males. In such a case, there appears to be egg-driven sperm selection against sperm from related males.
In toads, male advertisement vocalizations may serve as cues by which females recognize their kin and thus avoid inbreeding.
In dioecious plants, the stigma may receive pollen from several different potential donors. As multiple pollen tubes from the different donors grow through the stigma to reach the ovary, the receiving maternal plant may carry out pollen selection favoring pollen from less related donor plants. Thus, kin recognition at the level of the pollen tube apparently leads to post-pollination selection to avoid inbreeding depression. Also, seeds may be aborted selectively depending on donor–recipient relatedness.
See also
Attachment theory
Inclusive fitness
Kin selection
Nurture kinship
References
Evolutionary biology
Ethology
Kinship and descent
Selection
Organisms by adaptation | Kin recognition | [
"Biology"
] | 2,447 | [
"Evolutionary biology",
"Evolutionary processes",
"Behavior",
"Selection",
"Organisms by adaptation",
"Behavioural sciences",
"Ethology",
"Human behavior",
"Kinship and descent"
] |
11,801,987 | https://en.wikipedia.org/wiki/Omnibus%20Autism%20Proceeding | The Omnibus Autism Proceeding was a set of six test cases heard by Special Masters of the United States Court of Federal Claims to examine claims of a causal link between vaccines and autism.
Because there were so many National Vaccine Injury Compensation Program (NVICP) cases that involve a claim that vaccines caused autism, over 5000 of them in fact, the attorneys for the plaintiffs and the Special Masters agreed to examine three test cases to determine if there were sufficient evidence to support a link between vaccines and autism. They directly confronted the claim of whether there is evidence of causality between vaccines and autism.
In 2002, the NVICP, in consultation with a Petitioners Steering Committee, set up the Omnibus Autism Proceeding to aggregate these cases. They decided to examine six test cases that made one or more of the following claims about the vaccines-autism link:
• Claims that MMR vaccines and other thimerosal-containing vaccines can combine to cause autism.
• Claims that center on vaccines containing thimerosal causing autism.
• Claims that MMR vaccines alone (with no mention of thimerosal) can cause autism.
Three Special Masters examined the evidence for each of those claims. In 2009, they handed down their decisions. For each claim, the three Special Masters concluded that there were no links between vaccines and autism.
References
Vaccine controversies
MMR vaccine and autism | Omnibus Autism Proceeding | [
"Chemistry",
"Biology"
] | 273 | [
"Vaccination",
"Drug safety",
"Vaccine controversies"
] |
11,802,351 | https://en.wikipedia.org/wiki/Energy%20Research%20and%20Development%20Administration | The United States Energy Research and Development Administration (ERDA) was a United States government organization formed from the split of the Atomic Energy Commission (AEC) in 1975. It assumed the functions of the AEC not assumed by the Nuclear Regulatory Commission.
The agency was created as part of the Energy Reorganization Act of 1974, which was passed on October 11, 1974, in the wake of the 1973 oil crisis. The act split the Atomic Energy Commission into two new agencies: the Nuclear Regulatory Commission would regulate the commercial nuclear power industry, while the ERDA would manage the energy research and development, nuclear weapons, and naval reactors programs.
The Energy Research and Development Administration was established on January 19, 1975. The first administrator was Robert Seamans, followed by Robert W. Fri.
In 1977, ERDA was merged with the Federal Energy Administration to form the United States Department of Energy.
References
External links
DOE.gov: History of ERDA—Energy Research and Development Administration
Historical technical reports digitized by the Technical Report Archive & Image Library for ERDA
Governmental nuclear organizations
Nuclear history of the United States
Nuclear weapons infrastructure of the United States
Defunct independent agencies of the United States government
Government agencies established in 1974
1974 establishments in the United States
1977 disestablishments
United States Atomic Energy Commission
United States Department of Energy
Energy research | Energy Research and Development Administration | [
"Engineering"
] | 266 | [
"Governmental nuclear organizations",
"Nuclear organizations"
] |
11,802,934 | https://en.wikipedia.org/wiki/Reductive%20dual%20pair | In the mathematical field of representation theory, a reductive dual pair is a pair of subgroups (G, G′) of the isometry group Sp(W) of a symplectic vector space W, such that G is the centralizer of G′ in Sp(W) and vice versa, and these groups act reductively on W. Somewhat more loosely, one speaks of a dual pair whenever two groups are the mutual centralizers in a larger group, which is frequently a general linear group. The concept was introduced by Roger Howe in . Its strong ties with Classical Invariant Theory are discussed in .
Examples
The full symplectic group G = Sp(W) and the two-element group G′, the center of Sp(W), form a reductive dual pair. The double centralizer property is clear from the way these groups were defined: the centralizer of the group G in G is its center, and the centralizer of the center of any group is the group itself. The group G′, consists of the identity transformation and its negative, and can be interpreted as the orthogonal group of a one-dimensional vector space. It emerges from the subsequent development of the theory that this pair is a first instance of a general family of dual pairs consisting of a symplectic group and an orthogonal group, which are known as type I irreducible reductive dual pairs.
Let X be an n-dimensional vector space, Y be its dual, and W be the direct sum of X and Y. Then W can be made into a symplectic vector space in a natural way, so that (X, Y) is its lagrangian polarization. The group G is the general linear group GL(X), which acts tautologically on X and contragrediently on Y. The centralizer of G in the symplectic group is the group G′, consisting of linear operators on W that act on X by multiplication by a non-zero scalar λ and on Y by scalar multiplication by its inverse λ−1. Then the centralizer of G′, is G, these two groups act completely reducibly on W, and hence form a reductive dual pair. The group G′, can be interpreted as the general linear group of a one-dimensional vector space. This pair is a member of a family of dual pairs consisting of general linear groups known as type II irreducible reductive dual pairs.
Structure theory and classification
The notion of a reductive dual pair makes sense over any field F, which we assume to be fixed throughout. Thus W is a symplectic vector space over F.
If W1 and W2 are two symplectic vector spaces and (G1, G′1), (G2, G′2) are two reductive dual pairs in the corresponding symplectic groups, then we may form a new symplectic vector space W = W1 ⊕ W2 and a pair of groups G = G1 × G2, G′ = G′1 × G′,2 acting on W by isometries. It turns out that (G, G′) is a reductive dual pair. A reductive dual pair is called reducible if it can be obtained in this fashion from smaller groups, and irreducible otherwise. A reducible pair can be decomposed into a direct product of irreducible ones, and for many purposes, it is enough to restrict one's attention to the irreducible case.
Several classes of reductive dual pairs had appeared earlier in the work of André Weil. Roger Howe proved a classification theorem, which states that in the irreducible case, those pairs exhaust all possibilities. An irreducible reductive dual pair (G, G′) in Sp(W) is said to be of type II if there is a lagrangian subspace X in W that is invariant under both G and G′, and of type I otherwise.
An archetypical irreducible reductive dual pair of type II consists of a pair of general linear groups and arises as follows. Let U and V be two vector spaces over F, X = U ⊗F V be their tensor product, and Y = HomF(X, F) its dual. Then the direct sum W = X ⊕ Y can be endowed with a symplectic form such that X and Y are lagrangian subspaces, and the restriction of the symplectic form to X × Y ⊂ W × W coincides with the pairing between the vector space X and its dual Y. If G = GL(U) and G′ = GL(V), then both these groups act linearly on X and Y, the actions preserve the symplectic form on W, and (G, G′) is an irreducible reductive dual pair. Note that X is an invariant lagrangian subspace, hence this dual pair is of type II.
An archetypical irreducible reductive dual pair of type I consists of an orthogonal group and a symplectic group and is constructed analogously. Let U be an orthogonal vector space and V be a symplectic vector space over F, and W = U ⊗F V be their tensor product. The key observation is that W is a symplectic vector space whose bilinear form is obtained from the product of the forms on the tensor factors. Moreover, if G = O(U) and G′ = Sp(V) are the isometry groups of U and V, then they act on W in a natural way, these actions are symplectic, and (G, G′) is an irreducible reductive dual pair of type I.
These two constructions produce all irreducible reductive dual pairs over an algebraically closed field F, such as the field C of complex numbers. In general, one can replace vector spaces over F by vector spaces over a division algebra D over F, and proceed similarly to above to construct an irreducible reductive dual pair of type II. For type I, one starts with a division algebra D with involution τ, a hermitian form on U, and a skew-hermitian form on V (both of them non-degenerate), and forms their tensor product over D, W = U ⊗D V. Then W is naturally endowed with a structure of a symplectic vector space over F, the isometry groups of U and V act symplectically on W and form an irreducible reductive dual pair of type I. Roger Howe proved that, up to an isomorphism, any irreducible dual pair arises in this fashion. An explicit list for the case F = R appears in .
See also
Howe correspondence between representations of elements of a reductive dual pair.
Heisenberg group
Metaplectic group
References
.
.
.
Representation theory | Reductive dual pair | [
"Mathematics"
] | 1,442 | [
"Representation theory",
"Fields of abstract algebra"
] |
11,803,445 | https://en.wikipedia.org/wiki/Montia%20fontana | Montia fontana, blinks is a herbaceous annual to perennial plant that grows in freshwater springs in upland regions, and in seasonally damp acid grassland in the lowlands. It is widespread throughout the world, except in southern Asia. It is rather variable in morphology, which is reflected in a complex history of taxonomy. Currently, there are three accepted subspecies which are defined largely by the appearance of the seedcoat. It is edible and consumed as a salad in some areas, but is otherwise of minimal economic impact. Because of its association with clean water habitats, it is often viewed as a species of conservation value.
Description
Blinks is an annual to perennial prostrate herb with branching stems, sometimes forming mats up to 50 cm across in short, seasonally damp grassland or floating in streams and hollows. The stems are thin (0.5 mm diameter) and reddish, sometimes rooting in water. The primary roots are fleshy and pink, and there are numerous secondary roots with fibrous hairs.
The spatulate leaves are succulent and glabrous, arranged in opposite pairs, between 2–20 mm long and 1.5–6 mm wide, with a hydathode at the tip. On some plants, particularly those floating in water, the leaves have a distinct petiole, whereas on those (mainly subsp. chondrosperma) which grow in dry grassland, the leaves narrow towards their bases and fuse with the opposite one at the stem (i.e. they are connate).
The inflorescence consists of a terminal cyme of two or three tiny white flowers 2–3 mm in diameter with five petals, two sepals, 3-5 stamens, 1-3 styles, each with one stigma.
The fruit capsules are 2 mm in diameter and contain 3 round seeds. The architecture of the seeds differentiate the four varieties of blinks.
Taxonomy
The name Montia fontana was coined by Linnaeus in 1753 in Species Plantarum, but it has had many synonyms before and since; Linnaeus lists "Montia aquatica minor", "Cameraria aquatica minor" and "Portulaca arvensis" among them.
The generic name Montia is a tribute to Giuseppe Monti (1682-1760), a professor of botany at Bologna. The epithet fontana derives from the Latin fontanus, a spring, and refers to its habitat. The common name "blinks" may come from the phrase "blink and you miss it", due to its very small size, alternatively it may be from the Old English "blincan", to shine or twinkle. Other common names for it include "water blinks", "water chickweed" or (in the US) "annual water miner's lettuce".
Because blinks is such a widespread and variable species, many synonyms have been coined, and many subspecies have been described which reflect this variability. The currently accepted account is largely based on that of Max Walters in the British journal Watsonia in 1953. In this paper he described 4 subspecies:
subsp. fontana, which has smooth, shiny seeds 1.1-1.35 mm in diameter and occurs in very wet places worldwide, often growing as a floating plant with petiolate leaves.
subsp. chondrosperma (Fenzl) Walters, which has less shiny seeds 1.0-1.2 mm diameter and occurs on sandy soils in lowland places. It is a small plant (~1 cm tall) with connate leaf bases.
subsp. intermedia (Beeby) Walters, which has shiny tuberculate seeds 0.85-1.1 mm diameter and grows in very wet places in Western Europe and Australia. This is now called Montia fontana subsp. amporitana Sennen.
subsp. variabilis Walters, which has smooth seeds 0.9-1.1 mm diameter and grows grows in wet places in Britain and possibly elsewhere. This is no longer considered a valid taxon.
Distribution and status
Blinks has an almost world-wide distribution, and it is considered a native species in most places, and in all continents except Antarctica. It is apparently considered an introduction only in Venezuela and the Falkland Islands, and it is absent only from southern Asia.
The threat status of Blinks globally and in Europe is LC, as it is in Britain, where it is common and widespread in the north and west, becoming scattered and rare towards the south and east. Despite its abundance, it is listed as an axiophyte in most British counties.
Habitat and ecology
Blinks grows in a wide range of wetland habitats, from permanently wet pools, springs and streamsides to winter-wet, sandy grassland. It mostly grows in acid places, but is tolerant of mildly alkaline conditions. Its altitudinal range in Britain is from sea level to 996 m in Coire Leachavie, Glen Affric. The flowers are either pollinated by insects or (especially if underwater, when they are often cleistogamous) will self-pollinate.
Its Ellenberg values in Britain are L = 7, F = 9, R = 5, N = 3 and S = 0, which show that it occurs in fairly sunny places with slightly acid damp soils and low nutrient conditions. It is not tolerant of salt.
Under the European system for classifying habitats, EUNIS, Blinks is a characteristic species in three habitats, comprising four communities: C2.18 acid oligotrophic vegetation of spring brooks; C2.25 acid oligotrophic vegetation of fast-flowing stream; and D2.2C soft water spring mires, including D2.2C11 montane soft water moss springs. Within the British NVC blinks (particularly subsp. fontana) occurs in several types of upland spring-fed vegetation, most characteristically M35 Ranunculus omiophyllus-Montia fontana rills, and (mainly subsp. chondrosperma) in summer-dry, rain-fed U1 Festuca ovina-Agrostis capillaris-Rumex acetosella grassland in sandy, more lowland habitats.
Blinks is occasionally found in secondary populations in other habitats, such as woodland stream sides, where it has presumably been washed up, or in bowling greens or pavements after habitats have been built over.
The beetle Phaedon armoraciae chews on its leaves in Scotland, and the smut-like ascomycete Tolyposporium montiae (Rostrup) Rostrup, 1904 can infest the root collar area. There is a species of vinegar fly, Scaptomyza graminum whose larvae produce leaf mines in blinks; it has been recorded in Britain and Europe.
Uses
Blinks is edible and is gathered in the wild and used as a salad vegetable in Spain and Portugal, but it is not currently cultivated. It is high in fibre and is a rich source of omega-3 fatty acids.
References
External links
Jepson Manual Treatment
Photo gallery
fontana
Cosmopolitan species
Edible plants
Plants described in 1753
Taxa named by Carl Linnaeus | Montia fontana | [
"Biology"
] | 1,451 | [
"Cosmopolitan species",
"Organisms by location"
] |
11,803,513 | https://en.wikipedia.org/wiki/Self-service%20laundry | A self-service laundry, coin laundry, or coin wash, is a facility where clothes are washed and dried without much personalized professional help. They are known in the United Kingdom as launderettes or laundrettes, and in the United States, Canada, Australia and New Zealand as laundromats. In Texas and other parts of the south central United States, the term washateria is still used by some older speakers. The first laundromat opened on April 18, 1934 in Fort Worth, Texas.
Overview
While most homes have their own washers and dryers, self-service laundries are used by many who do not have their own machines. Even those who have their own machines sometimes use them for large bedding and other items that cannot fit into residential washers and dryers.
Staffed laundries
Laundromats are an essential business in urban communities. Laundromat owners may employ someone to oversee and maintain the general laundromat throughout the day. Some laundries employ staff to provide service for the customers. Minimal service centres may simply provide an attendant behind a counter to provide change, sell laundry detergent, and watch unattended machines for potential theft of clothing. If the business is big enough, the owner may employ a plumber to constantly maintain the machines and other workings.
Others allow customers to drop off clothing to be washed, dried, and folded. This is often referred to as fluff & fold, wash-n-fold, drop off, bachelor bundles, a service wash or full-service wash. Some staffed laundry facilities also provide dry cleaning pick-up and drop-off. There are over 35,000 laundries throughout the United States. Similar services exist in the United Kingdom where the terms service wash or full-service wash are also in use. The evolution of self-serve laundry services have been seen in some "fluff and fold" (also styled fluff n fold, fluff & fold, fluff 'n' fold, and fluff 'n fold) services provided by various laundromats. These services provide the end user with washing, drying, and folding services on a per pound basis. Some services offer free pickup and delivery, as well as complimentary laundry bags as part of their customer appreciation. Additionally, dry-cleaning services have been known to utilize the pickup and delivery as a means to help generate additional revenue.
On-premise laundromats
On-premise laundromats are found in locations such as hotels, hospitals, student residences at universities, or apartment blocks. Facility managers/maintenance staff work directly with machine distributors to supply and maintain washers and dryers. Use of the machines are primarily reserved for the residents of these facilities.
Many building owners use on-premise laundromats as a way to increase revenue. They can do this through renting their laundry room to laundry companies for a fixed monthly price allowing the laundry company to keep all revenue from the machines. Building owners also have the option to create a revenue sharing system where the apartment owner and laundry company split the profits from the machines each month.
By country
Spain
In Spain, self-service laundries are available and popular mainly in Burgos, where there is a large network of laundromats.
Andorra
In Andorra, self-service laundries are widely available and in use by a good percentage of the population. Due to its cold weather, Andorra has a much larger percentage of dryer owners, as the cold weather doesn't allow for hanging laundry outside for most of the year, with the exception of a few months. The long Andorra winter sees a large usage of drying machines, also easily found in self-service laundries.
Australia
In Australia, self-service laundries are widely available and in use by a good percentage of the population. Due to its mild weather, Australia has a much smaller percentage of dryer owners, as the mild weather allows for hanging laundry outside for most of the year, with the exception of a few months. The brief Australian winter sees a surge in the usage of drying machines, usually easily found in self-service laundries.
Israel
In Israel, self-service laundries are available and popular mainly in Tel Aviv, where there is a large network of laundromats.
Portugal
Self-service laundries are present in Portugal.
New Zealand
In New Zealand self-service laundries (known locally as laundromats) are available, but not widely used. Historically, most houses in New Zealand have had their own laundry rooms for clothes washing. In recent decades the number of people living in smaller flats and apartments has increased, and so too has the availability and use of laundromats, especially in larger cities such as Auckland and Wellington.
United Kingdom
The first UK launderette (alternative spelling: laundrette) was opened on 9 May 1949 in Queensway, London. UK launderettes are mainly fully automated and coin operated, and are either fully staffed, staffed during certain hours, or unstaffed. They are generally found only in urban and suburban areas, where they have been common features since the 1960s.
From 1985 to 2010, the number of launderettes has declined, with only around 3000 remaining. Rapidly rising utility charges, premises rent and a lower purchase cost of domestic machines have been noted as principal reasons for the recent decline. High initial launch costs, specifically for commercial washing machines and dryers, have also been commented on as reasons for fewer new entrants into the market. Furthermore, machine updates can be prohibitively expensive, which has held back premises' investment.
Many of the staffed operations in the UK have added-value services such as ironing, dry cleaning and service washes, which are popular among professionals, students, and senior citizens. Student accommodation blocks often have their own unstaffed laundries, which are typically run at a profit by the accommodation provider.
Local phone directories only show laundries that pay to be included, so trends are difficult to assess. However, large cities such as Birmingham, Bristol, Leeds, Liverpool, London, Manchester, Sheffield and Southampton have significant numbers of launderettes, as do many coastal tourist areas.
The main manufacturers serving the UK in this market are Electrolux, IPSO, Maytag, and Primus. Brands such as Frigidaire and Speed Queen are also regularly deployed, with most originating from Belgium and the US.
United States
Self-service laundry facilities in the United States are most commonly called laundromats. The term "laundromat" is the genericized trademark of the Westinghouse Electric Corporation, later White Consolidated Industries, and was created by its employee, George Edward Pendray. "Washateria" is an alternate name for laundromat, but is not in common use outside of Texas. The term comes from the first laundromat in the United States, which was known as a washateria and was opened on 18 April 1934 in Fort Worth, Texas, by C.A. Tannahill. Though steam-powered laundry machines were invented in the 19th century, their cost put them out of reach of many. Cantrell and others began renting short-term use of their machines. Most laundromats in the US are fully automated and coin-operated and generally unstaffed, with many operating 24 hours a day. The invention of the coin-operated laundry machine is ascribed to Harry Greenwald of New York who created Greenwald Industries in 1957; the company marketed the devices through the 20th century. While coin laundromats are very common, some laundromats accept credit cards or provide their own card system.
The United States Census Bureau estimates that there are 11,000 of this style of laundromat in the US, employing 39,000 people and generating over $3.4 billion every year.
In popular culture
My Beautiful Laundrette, 1985 film
My Beautiful Laundrette, 2019 play adapted from the above film and written by the same individual who wrote the film's screenplay (Hanif Kureishi)
See also
Laundress or washerwoman, who used to do similar work
Mangle (machine)
References
External links
Coin Laundry Association, a not-for-profit trade organization for the self-service laundry industry
Laundry places
Cleaning industry | Self-service laundry | [
"Technology"
] | 1,715 | [
"Information systems",
"Self-service"
] |
11,804,488 | https://en.wikipedia.org/wiki/Lee%20Paul | Paul Lee Kroll, also known as Lee Paul, (June 16, 1939 – September 22, 2019) was an American film and television actor. He was perhaps best known for playing as the bodyguard of Doyle Lonnegan (Robert Shaw) in the 1973 film The Sting, alongside actor Charles Dierkop who played the role of Floyd.
Paul was born in the United States, where he was raised in Brooklyn, New York. He attended at a college in Marietta, Ohio, in which he then served in the United States Air Force. Paul guest-starred in numerous television programs including Hawaii Five-O, Quincy, M.E., Wonder Woman, Fantasy Island, Tenspeed and Brown Shoe, The Rookies, The Fall Guy, Simon & Simon, Emergency!, Ironside, Police Woman, Matlock, Falcon Crest, Cannon, Happy Days, Mannix, Adam-12 and Mission: Impossible.
Paul was married to dancer Kathy Kroll. He was a emigrant to Sweden for Swedish-American Day. Paul worked as a petroleum engineer. He died in September 2019, at the age of 80.
Partial filmography
Mission Impossible (1971-1972) - Gristin, Schmidt
Ben (1972) - Careu
The Sting (1973) - Lonnegan's bodyguard
The Rookies (1973) - Tim Duvall
Kung Fu (1973) - Gilchrist
Scream of the Wolf (1974) - Student
’’Get Christie Love’’ (1974) - Pilot Episode, Max Loomis
Happy Days (1974) - Mory
The Island at the Top of the World (1974) - Chief of Boat Archers
Police Woman (1975 - 1977)
Emergency! (1975) - Pete
The Fall Guy (1985) - Henchman
Deadly Friend (1986) - Sergeant Charlie Volchek
Survival Game (1987) - McClean
The Van Dyke Show (1988) - Al
References
External links
Rotten Tomatoes profile
1939 births
2019 deaths
American male film actors
American male television actors
20th-century American male actors
American emigrants to Sweden
Petroleum engineers | Lee Paul | [
"Engineering"
] | 415 | [
"Petroleum engineers",
"Petroleum engineering"
] |
11,805,081 | https://en.wikipedia.org/wiki/4-PPBP | 4-PPBP is a neuroprotective cyclic amine which binds to sigma receptors.
4-PPBP decreases neuronal nitric oxide synthase (nNOS) activity and ischemia-evoked nitric oxide (NO) production. 4-PPBP provides neuroprotection; this involves the prevention of ischemia-induced intracellular Ca2+ dysregulation. 4-PPBP protects neurons using a mechanism that activates the transcription factor cyclic adenosine monophosphate response element-binding protein (CREB). Neuroprotection that is associated with 4-PPBP increases Bcl-2 expression; Bcl-2 expression is regulated by CREB.
See also
3-PPP
References
4-Phenylpiperidines
Sigma agonists | 4-PPBP | [
"Chemistry",
"Biology"
] | 175 | [
"Biochemistry stubs",
"Biotechnology stubs",
"Biochemistry"
] |
11,805,232 | https://en.wikipedia.org/wiki/Siramesine | Siramesine (or Lu 28-179) is a sigma receptor agonist, selective for the σ2 subtype. In animal studies, siramesine has been shown to produce anxiolytic and antidepressant effects. It was developed by the pharmaceutical company H Lundbeck for the treatment of anxiety, although development was discontinued after clinical trials showed a lack of efficacy in humans. Siramesine has been shown to produce an enhanced antidepressant effect when co-administered with NMDA antagonists. It has also been used to study the σ2 activity of cocaine, and has been shown to produce anticancer properties both in vitro and in vivo.
References
External links
Abandoned drugs
Anxiolytics
Sigma agonists
4-Phenylpiperidines
Indoles
4-Fluorophenyl compounds
Spiro compounds
Isobenzofurans | Siramesine | [
"Chemistry"
] | 180 | [
"Pharmacology",
"Drug safety",
"Medicinal chemistry stubs",
"Organic compounds",
"Pharmacology stubs",
"Abandoned drugs",
"Spiro compounds"
] |
11,805,314 | https://en.wikipedia.org/wiki/Sigma-2%20receptor | The sigma-2 receptor (σ2R) is a sigma receptor subtype that has attracted attention due to its involvement in diseases such as neurological diseases, neurodegenerative, neuro-ophthalmic and cancer. It is currently under investigation for its potential diagnostic and therapeutic uses.
Although the sigma-2 receptor was identified as a separate pharmacological entity from the sigma-1 receptor in 1990, the gene that codes for the receptor was identified as TMEM97 only in 2017. TMEM97 was shown to regulate the cholesterol transporter NPC1 and to be involved in cholesterol homeostasis. The sigma-2 receptor is a four-pass transmembrane protein located in the endoplasmic reticulum. It has been found to play a role in both hormone signaling and calcium signaling, in neuronal signaling, in cell proliferation and death, and in binding of antipsychotics.
Classification
The sigma-2 receptor is located in the lipid raft. The sigma-2 receptor is found in several areas of the brain, including high densities in the cerebellum, motor cortex, hippocampus, and substantia nigra. It is also highly expressed in the lungs, liver, and kidneys.
Function
The sigma-2 receptor takes part in a number of normal-function roles such as cholesterol homeostasis.
Non-neuronal signaling
Binding of a number of hormones and steroids, including testosterone, progesterone, and cholesterol, has been found to occur with sigma-2 receptors, though in some cases with lower affinity than to the sigma-1 receptor. Signaling caused by this binding is thought to occur via a calcium secondary messenger and calcium-dependent phosphorylation, and in association with sphingolipids following endoplasmic reticulum release of calcium. Known effects include decrease of expression of effectors in the mTOR pathway, and suppression of cyclin D1 and PARP-1.
Neuronal signaling
Signaling action in neurons by sigma-2 receptors and their associated ligands results in modulation of action potential firing by regulation of calcium channels and potassium channels. They also are involved in synaptic vesicular release and modulation of dopamine, serotonin, and glutamate, with activation and increase of the dopaminergic, serotonergic, and noradrenergic activity of neurons.
Cell proliferation
Sigma-2 receptors have been found to be highly expressed in proliferating cells, including tumor cells, and to play a role in the differentiation, morphology, and survival of those cells. By interacting with EGFR membrane proteins sigma-2 receptors play a role in the regulation of signals further downstream such as PKC and RAF. Both PKC and Raf kinase up regulate transcription and cell proliferation.
Ligands
Ligands of the sigma-2 receptor are exogenous and internalized by endocytosis, and can act as either agonists or antagonists. They can typically be classified into four groups, which are structurally related. It is not entirely understood how binding to the sigma-2 receptor occurs. Proposed models commonly include one small and one bulky hydrophobic pocket, electrostatic hydrogen interactions, and less commonly a third hydrophobic pocket.
A study of the four groups has revealed that a basic nitrogen and at least one hydrophobic moiety is needed to bind a sigma-2 receptor. In addition, there are molecular characteristics that increase the selectivity for sigma-2 receptors, which include bulky hydrophobic regions, nitrogen-carboxylic interaction, and additional basic nitrogens.
Since its discovery in 1990, the sigma-2 receptor has been considered an orphan receptor; however, in 2021 20S-hydroxycholesterol was identified as the putative endogenous ligand.
Another ligand is Lu 29-252.
Diagnostic use
Sigma-2 receptors are highly expressed in breast, ovarian, lung cancers, brain, bladder, colon cancers, and melanoma. This novelty makes them a valuable biomarker for identifying cancerous tissues. Furthermore, studies have shown that they are more highly expressed in malignant tumors than dormant tumors.
Exogenous sigma-2 receptor ligands have been altered to be neuronal-tracers, used to map cells and their connections. These tracers have high selectivity and affinity for sigma-2 receptors, and high lipophilicity, making them ideal for usage in the brain. Because sigma-2 receptors are highly expressed in tumor cells and are part of the cell proliferation mechanism, PET scans using sigma-2 targeted tracers can reveal if a tumor is proliferating and what its growth rate is.
Therapeutic use
Neurodegenerative and Neuro-ophthalmic Diseases
The sigma-2 receptor is expressed in brain and retinal cells where it regulates key pathways involved in age-related diseases such as Alzheimer's disease and synucleinopathies such as Parkinson's disease and dementia with Lewy bodies, as well as dry age-related macular degeneration (dry AMD). The normal activity of processes regulated by sigma-2, such as protein trafficking and autophagy, is impaired by cellular stresses such as oxidative stress and the build-up of amyloid-β and α-synuclein oligomers. Studies support that sigma-2 modulators can rescue biological processes that are impaired in neurodegenerative diseases.
In vitro studies of experimental sigma-2 receptor modulators demonstrated an ability to prevent the binding of amyloid-β oligomers to neurons and also to displace bound amyloid-β oligomers from neuronal receptors. In addition, transgenic mice treated sigma-2 receptor modulators performed significantly better in the Morris water maze task than did vehicle-treated mice. Taken together, these studies suggest that sigma-2 receptor modulation may be a viable approach for treating certain neurodegenerative diseases of the CNS and retina.
Neuropsychiatric
Due to the binding capabilities of antipsychotic drugs and various neurotransmitters associated with mood, the sigma-2 receptor is a viable target for therapies related to neuropsychiatric disorders and modulation of emotional response. It is thought to be involved in the pathophysiology of schizophrenia, and sigma-2 receptors have been shown to be less abundant in schizophrenic patients. Additionally, PCP, which is an NMDA antagonist, can induce schizophrenia, while sigma-2 receptor activation has been shown to antagonize effects of PCP, implying antipsychotic capabilities. Sigma receptors are a potential target for treatment of dystonia, given high densities in affected regions of the brain. Anti-ischemics ifenprodil and eliprodil, the binding of which increases blood flow, have also shown affinity to sigma receptors.
In experimental trials in mice and rats, the sigma-2 receptor ligand siramesine caused reduced anxiety and displayed antidepressant capabilities, while other studies have shown inhibition of selective sigma receptor radioligands by antidepressants, in the mouse and rat brain.
Cancer
Sigma-2 receptors have been associated with pancreatic cancer, lung cancer, breast cancer, melanoma, prostate cancer, and ovarian cancer. Tumor cells are shown to over-express sigma-2 receptors, allowing for potential cancer therapies as many sigma-2 receptor mediated cell responses happen only in tumor cells. Tumor cell responses are modulated via ligand binding. Sigma receptor ligands can act as agonists or antagonists, generating different cellular responses. Agonists inhibit tumor cell proliferation and induce apoptosis, which is thought to be triggered by caspase-3 activity. Antagonists promote tumor cell proliferation, but this mechanism is less understood. Sigma receptor ligands have been conjugated to nanoparticles and peptides to deliver cancer treatment to tumor cells without targeting other tissues. The success with these methods have been limited to in vitro trials. Additionally, using sigma-2 receptors to target tumor cells allows for synergizing anti-cancer drug therapies. Some studies have shown that certain sigma receptor inhibitors increase cancer cells' susceptibility to chemotherapy. Other types of binding to sigma-2 receptors increases cytotoxicity of doxorubicin, antinomyocin, and other cancer cell killing drugs.
See also
Sigma-1 receptor
Sigma receptor
SAS-1121, a tool compound preferentially binding to the sigma-2 receptor
References
External links
Signal transduction
Cell signaling | Sigma-2 receptor | [
"Chemistry",
"Biology"
] | 1,786 | [
"Biochemistry",
"Neurochemistry",
"Signal transduction"
] |
11,805,449 | https://en.wikipedia.org/wiki/PB-28 | PB-28 is an agonist of the sigma-2 receptor.
It is derived from cyclohexylpiperazine.
References
External links
Phenol ethers
Piperazines
Cyclohexyl compounds | PB-28 | [
"Chemistry",
"Biology"
] | 47 | [
"Biochemistry stubs",
"Biotechnology stubs",
"Biochemistry"
] |
11,806,446 | https://en.wikipedia.org/wiki/Inferior%20ligament%20of%20epididymis | The inferior ligament of the epididymis is a strand of fibrous tissue which is covered by a reflection of the tunica vaginalis and connects the lower aspect of the epididymis with the testis.
Sexual anatomy
Ligaments | Inferior ligament of epididymis | [
"Biology"
] | 52 | [
"Sexual anatomy",
"Sex"
] |
11,806,561 | https://en.wikipedia.org/wiki/Superior%20ligament%20of%20epididymis | The superior ligament of the epididymis is a strand of fibrous tissue which is covered by a reflection of the tunica vaginalis and connects the upper aspect of the epididymis with the testis.
Sexual anatomy
Ligaments | Superior ligament of epididymis | [
"Biology"
] | 52 | [
"Sexual anatomy",
"Sex"
] |
11,807,158 | https://en.wikipedia.org/wiki/Sleeve%20%28construction%29 | In construction, a sleeve is used both by the electrical and mechanical trades to create a penetration in a solid wall, ceilling or floor.
Purpose
For cables we provide wall/deck penetration sleeve to avoid any damage to cable from material shifting on deck.
Deck penetrations on offshore platform provided to avoid water/chemical dripping to lower deck in case of spillage.
Acts as toe guard.
For wall penetrations it can be a type of strengthening.
Together with packing it helps to protect from fire spread from one room to other.
Materials
Sleeves can be made of:
sections of steel pipe.
plastic.
sheet metal.
proprietary devices that are listed firestop components.
Requirements
Sleeves must be sized such as to adequately allow the passage of the intended penetrant(s) plus enough room to permit the practical installation and mounting of the penetrants as well as adequate room for firestops. A general practice is to size the sleeve two NPS (pipe sizes) up from the diameter of the penetrant. For example, a 4" pipe, with 1" of thermal insulation makes a 6" penetrant (1" pipe covering on each side of the pipe), plus two pipe sizes = an 8" sleeve, creating a 1" annulus.
In case of insulated piping, the size of the insulation must be taken into account for the intended firestop certification listing.
Hazards
Metallic sleeves are heatsinks in the firestop that follows the mounting of the penetrants. Maximum and minimum tolerances for wall thicknesses must be taken into account prior to casting. Heatsinks can affect T-ratings. Organic sealants used for topcaulking in firestops may let go of the sleeve if it has conducted too much heat through to the unexposed side (as in the case of the fire test article, this picture).
Plastic sleeves are usually removed after the concrete forms are stripped, as they contribute fuel to an accidental fire.
See also
Piping
Firestop
Packing (firestopping)
Penetration (firestop)
Penetrant (mechanical, electrical, or structural)
Annulus (firestop)
Fire-resistance rating
Fire test
Heat sink
External links
CAL State University Section 15050 Spec, including Sleeves
UVA Virginia Hospital Section 15050 Specification, including Sleeves
Piping
Passive fire protection | Sleeve (construction) | [
"Chemistry",
"Engineering"
] | 469 | [
"Piping",
"Chemical engineering",
"Mechanical engineering",
"Building engineering"
] |
11,807,208 | https://en.wikipedia.org/wiki/Millennium%20Tower%20%28Tokyo%29 | Millennium Tower was a 180-floor skyscraper that was envisioned by architect Sir Norman Foster in 1989. He intended for it to be built in Tokyo Bay, 2 km offshore from Tokyo, Japan.
Design
The design calls for a cone-shaped pyramid 840 meters high, with a base about as big as the Tokyo Olympic Stadium and glass sides for natural lighting. It is intended to be constructed on water, with boat and bridge access. Since the tower was planned for an area with frequent earthquakes and hurricane-strength winds, the shape is aerodynamic to reduce wind stress, and helical bands are wrapped around the tower for structural support. Steel tanks at the top of the tower are filled with water, and can be rotated as a counterweight against wind.
The tower is a self-contained arcology containing one million square meters of commercial development and housing for 60,000 people, split into sections. Offices and light or clean industries are in the lower levels, apartments above, and the top section houses communications systems and wind or solar generators. Restaurants and viewing platforms would be interspersed through all sections.
Horizontal and vertical high-speed metro lines provide long-distance travel, with cars designed to carry 160 people stopping at intermediate five-story 'sky centers' on every thirtieth floor. Each 'sky center' is decorated by gardens and mezzanines, and provides a particular service such as hotels or restaurants. Short-distance travel is by elevators or escalators.
History
The tower design was commissioned by the Obayashi Corporation as an arcology, intended to address land shortage and overpopulation in Tokyo. The design firm's web site states that "the project demonstrates that high-density or high-rise living does not mean overcrowding or hardship; it can lead to an improved quality of life, where housing, work and leisure facilities are all close at hand".
References
(Foster & Partners)
"Millenium Tower", Skyscraperpage
Skyscrapers in Tokyo
Proposed skyscrapers in Japan
Unbuilt buildings and structures in Japan
Unbuilt skyscrapers
Proposed arcologies | Millennium Tower (Tokyo) | [
"Technology"
] | 422 | [
"Exploratory engineering",
"Proposed arcologies"
] |
11,807,746 | https://en.wikipedia.org/wiki/Obelisk%20posture | The obelisk posture is a handstand-like position that some dragonflies and damselflies assume to prevent overheating on sunny days. The abdomen is raised until its tip points at the sun, minimizing the surface area exposed to solar radiation. When the sun is close to directly overhead, the vertical alignment of the insect's body suggests an obelisk.
Function and occurrence
Dragonflies may also raise their abdomens for other reasons. For instance, male blue dashers (Pachydiplax longipennis) assume an obelisk-like posture while guarding their territories or during conflicts with other males, displaying the blue pruinescence on their abdomens to best advantage. However, both females and males will raise their abdomens at high temperature and lower them again if shaded. This behavior can be demonstrated in the laboratory by heating captive blue dashers with a 250 watt lamp, and has been shown to be effective in stopping or slowing the rise in their body temperature.
The obelisk posture has been observed in about 30 species in the demoiselle, clubtail, and skimmer families. All are "perchers"—sit-and-wait predators that fly up from a perch to take prey and perch again to eat it. Since they spend most of their time stationary, perchers have the most opportunity to thermoregulate by adjusting their position.
Other forms of postural thermoregulation
Some species, including the dragonhunter (Hagenius brevistylus), reduce exposure to the sun by perching with the abdomen pointed downward, rather than upward. The tropical skimmer dragonfly Diastatops intensa, whose wings are mostly black, points its wings rather than its abdomen at the sun, apparently to reduce the heat they absorb.
While flying, some saddlebags gliders (genus Tramea) lower their abdomens into the shade provided by dark patches at the bases of their hindwings. The same behavior has been observed in Pseudothemis zonata, which has a similar hindwing patch.
Dragonflies also use postural thermoregulation to increase body temperature. Keeping the flight muscles in the thorax warm is especially important, since otherwise the insect cannot fly. Dragonflies may position their wings to reflect sun onto themselves, or, if they are perched on a warm surface, to form a "greenhouse" over the thorax. When the sun is low in the sky, they may raise or lower their abdomens so that their bodies are perpendicular to the sun's rays, maximizing the surface area that receives direct sun; although this can resemble the obelisk posture, the purpose is opposite.
Notes
References
Further reading
Ethology
Odonata | Obelisk posture | [
"Biology"
] | 555 | [
"Behavioural sciences",
"Ethology",
"Behavior"
] |
11,808,054 | https://en.wikipedia.org/wiki/Front%20yard | On a residential area, a front yard (United States, Canada, Australia) or front garden (United Kingdom, Europe) is the portion of land between the street and the front of the house. If it is covered in grass, it may be referred to as a front lawn. The area behind the house, usually more private, is the back yard or back garden. Yard and garden share an etymology and have overlapping meanings.
In North America, front yards, which normally include considerable driveway and parking space, tend to be mostly lawn even when large, but in Europe they are often treated as a flower garden and may be heavily planted. In North American suburbia, there may be no physical barriers marking the front and sides of the plot, which would be very unusual in Europe, where there are generally walls, fences or hedges on three sides of the garden.
Features
While the front yard's counterpart, the backyard, is often dominated by utilitarian features like vegetable gardens, tool sheds, and clothes lines, the front yard is often a combination decorative feature and recreation area. It is more commonly landscaped for display and is the usual place for display elements such as garden gnomes, plastic flamingos, and yard shrines such as "bathtub Madonnas". An article on London suburbs describes a "model" front garden in Kenton: "The grass ... is neatly mown. There is a flowering cherry and a privet hedge, behind which lurks a plaster gnome."
Depending on climate, local planning regulations or size, a front yard may feature a lawn or grassed area, a driveway or footpath or both and gardens or a vegetable patch or potted plants.
History and styles
Australia
The history of the Australian front yard is said to have begun with a regulation enacted in New South Wales in 1829 mandating that new houses be built at least from the street to ensure adequate space in front of each house for a garden.
By the early 1900s, the front yard had become an accepted, "buffer between the private home and the public street". Australians adopted the American ideal of front yards without fences to create "park-like" streets and suburb-wide efforts were undertaken to remove fences and thereby encourage good neighbourly relationships and discourage anti-social behaviour and crime. Daceyville in Sydney was the first suburb where fencing was systematically removed and soon public housing organisations in other states followed the trend. Some even encouraged front yard beautification by running competitions with cash prizes.
During the construction of Australia's planned capital, Canberra, (in the late 1920s) the Federal Capital Commission provided government subsidies to encourage new residents to regularly maintain their front yards.
By the 1950s, there was a clear delineation between front and back yards. There was also, by then, a very clear street-view approach to garden design with the house façade and front yard considered in unison; to "view the whole effect from the street".
Canada
The development and history of Canadian front yards generally followed early American trends but diverged in the early 1900s.
In the 1920s and 30s, zoning laws were introduced for growing cities like Ottawa and Vancouver. The regulations stipulated minimum front yard "depth" for new houses and ensured home builders shunned the "tenement house evil" of New York City and London.
In many parts of Canada, lower average temperatures and a more pronounced want for privacy led to the increased popularity of tall trees at the side borders of housing blocks, framing the house and front yard. These provided wind breaks in winter and shade in the summer. Lawn ornaments were less common in pre and post-war Canada than in the United States and a large well-kept tract of "featureless" lawn was popular with many middle-class Canadians.
In the post-war era, suburban Canada gained its own distinctive architectural styles and this extended to front yards and gardens. Rather than the stark white façades of stately American houses, wealthy Canadians of the 60s and 70s showed a preference for wood, in particular "diagonal cedar panelling". To match that trend, front yards of such houses were often paved to match the entrances of modern city buildings; "no elite home of the 1970s was complete without a front yard of interlocking brick".
As in other cultures, Canadian front yards became areas of socialisation between the public street and the private home; a space for street parties, family barbecues and neighbourly conversation.
Europe
In many parts of Europe, the space in question is referred to as a front garden.
The earliest form of front garden was the open courtyard popular with Spanish and Italian nobility. As housing evolved, so too did gardens and façades. Enclosed courtyards were surpassed in popularity by the large manicured gardens of French, German and Dutch palaces and stately homes. These traditions were carried by the Europeans to the Americas where courtyards remained popular among Spanish settlers in Florida while productive cottage gardens became commonplace among Dutch settlers and English pilgrims in Massachusetts.
As suburbs developed around major European cities, the attitude to privacy, and by extension to front gardens, was decidedly different from that of the British. As one Dutch commentator highlighted (in the 1950s):
In older cities and townships (with houses built several centuries earlier) front gardens are far less common, with front doors providing residents with access direct to the street. In these cases, planter boxes and micro-gardens have become popular as a way of "greening" façades that would otherwise be without plants; elements that make a, "significant contribution to the quality of the environment".
United Kingdom
In British English, the space in question is referred to as a front garden.
Urban housing in the United Kingdom originally had no separation between the house front and the street. The introduction of the byelaw terraced house, a type of dwelling built to comply with the Public Health Act 1875, raised the standards of accommodation. The provision of a front garden in new houses became common practice during the second half of the 19th century as part of the Domestic Revival style within Victorian architecture: "to provide for the majority of new, even fairly modest, houses, a small front garden or paved forecourt, and a garden or yard at the back". Front gardens were "commonplace" for new residences by the 1870s. The front garden was "largely ornamental" and initially more important than the back, which was sometimes eliminated to allow more space for service areas. A fairly standard layout was adopted with a stone or brick wall to emulate the "grandeur of approach and walled privacy of large houses" and a straight path from the gate to the front door. Often, the cottage garden style of thick planting of mixed types of flowers was adopted. This supposedly originated in the gardens of rural cottages, where front gardens had long been common. In the houses of the working class, the small rear garden was often more functional, as a space for drying clothes, having children play and the like, and any efforts at ornamental gardening took place in the front garden.
Early in the 20th century, housing developments influenced by the garden city movement, initiated by Ebenezer Howard in 1898, featured detached houses with undivided "communal grass areas" in front of them. In essence, the houses shared a front garden.
However, outside these developments the dominant form of new housing in the United Kingdom until after World War II, especially in London, was the semi-detached, which superseded the previous dominant terraced house and where a garden was part of the ideal. The front garden, smaller than the back, was separated from the street by a lower wall than in the Victorian house; some developers planted hedges and provided instructions on their care. Gardening was a widely shared hobby and source of pride; developers sometimes prepared the front garden (almost never the back) as an inducement to buy, and sometimes held contests for the best front garden. However, since the houses were not always provided with garages, as motor vehicles became more common, the front garden was increasingly often used as a car parking area or enclosed by a garage.
During the Great Depression, local authorities encouraged families to grow produce in their own front gardens, thereby increasing community food supplies. Gardening was introduced in some schools, and towns introduced competitions and awards for attractive and productive front gardens. (See Dig for victory.)
In the post-war era of the 1950s and 60s, many of those front garden areas used for parking were paved over and became mini-driveways. This trend also became more common as professional gardeners became less common, thus increasing the need for home owners to maintain what was often a very small section of lawn or planted garden.
United States
As residential areas were subdivided and developed during the late 19th and early 20th centuries, the "suburban ideal" demanded large front yards, "dominated" by the facades of the houses they bounded.
The size of new front yards gradually decreased during the second half of the 20th century as houses were built closer and closer to the front of housing blocks.
In the 1870s, lawn ornaments became a popular front yard feature, with wrought iron sculpture, bird baths and gazebos being particularly popular. Throughout the 1880s and 90s, wicker lawn furniture became popular before being replaced in the early 1900s by nursery rhyme character and animal ornaments. In the post-war period, kitsch ornaments including plastic flamingoes and garden gnomes became popular.
During the 1930s a new American Style took hold, inspired by the architectural designs of Frank Lloyd Wright, Bernard Maybeck and Greene and Greene; "informality, naturalness, interlocking indoor-outdoor design, greatly reduced flower-beds, privacy for outdoor recreation and leisure...".
Local ordinances determine what owners and residents can and cannot do in their front yards. In recent times, sustainability enthusiasts and practitioners have attempted to use their front yards to grow organic produce, in violation of existing codes. In Orlando, Florida, for example, city codes set standards for front yard ground covering and prescribe lawns only. Residents there have received citations for breaching the code by growing vegetable gardens and are currently fighting to have the ordinances amended. The illegality of growing vegetables in the front yard first received public attention due to the Oak Park incident in 2011. The "Urban Farming Guidebook — Planning for the Business of Growing
Food in BC's Towns & Cities" provides an explanation to this recurring phenomenon "The Garden City model embraced food production and its systems as key elements of community design. However, the race to the single use zoned suburbs did not include food production as part of the design of suburbs....urban farming was excluded from our lists of permitted uses and such farming became non-conforming or simply illegal uses which, if they were lucky, avoided bylaw attention".
Since the early 2000s, once-common front yard "accoutrements" (like basketball rings on garages) are becoming less common; many are now prohibited by local government ordinances.
See also
Backyard
Back garden
Front Yards in Bloom
Setback (land use)
List of garden types
References
Further reading
The Average Yard by Harold A. Caparn (1937)
The New American Front Yard: Kiss Your Grass Goodbye by Sarah Carolyn Sutton (Tendril Press, 2013)
Front Yard Machines: Interpreting Cultural Landscapes by Markus Lahtinen (Lightning Source, 2008)
Rediscovering and Recovering the Front Yard: A Study of Garden Yard Meaning and Owner Attitudes by Gillian Jurkow (University of Manitoba, 2000)
Gardens
Landscape architecture | Front yard | [
"Engineering"
] | 2,320 | [
"Landscape architecture",
"Architecture"
] |
11,808,249 | https://en.wikipedia.org/wiki/Genome-wide%20association%20study | In genomics, a genome-wide association study (GWA study, or GWAS), is an observational study of a genome-wide set of genetic variants in different individuals to see if any variant is associated with a trait. GWA studies typically focus on associations between single-nucleotide polymorphisms (SNPs) and traits like major human diseases, but can equally be applied to any other genetic variants and any other organisms.
When applied to human data, GWA studies compare the DNA of participants having varying phenotypes for a particular trait or disease. These participants may be people with a disease (cases) and similar people without the disease (controls), or they may be people with different phenotypes for a particular trait, for example blood pressure. This approach is known as phenotype-first, in which the participants are classified first by their clinical manifestation(s), as opposed to genotype-first. Each person gives a sample of DNA, from which millions of genetic variants are read using SNP arrays. If there is significant statistical evidence that one type of the variant (one allele) is more frequent in people with the disease, the variant is said to be associated with the disease. The associated SNPs are then considered to mark a region of the human genome that may influence the risk of disease.
GWA studies investigate the entire genome, in contrast to methods that specifically test a small number of pre-specified genetic regions. Hence, GWAS is a non-candidate-driven approach, in contrast to gene-specific candidate-driven studies. GWA studies identify SNPs and other variants in DNA associated with a disease, but they cannot on their own specify which genes are causal.
The first successful GWAS published in 2002 studied myocardial infarction. This study design was then implemented in the landmark GWA 2005 study investigating patients with age-related macular degeneration, and found two SNPs with significantly altered allele frequency compared to healthy controls. , over 3,000 human GWA studies have examined over 1,800 diseases and traits, and thousands of SNP associations have been found. Except in the case of rare genetic diseases, these associations are very weak, but while each individual association may not explain much of the risk, they provide insight into critical genes and pathways and can be important when considered in aggregate.
Background
Any two human genomes differ in millions of different ways. There are small variations in the individual nucleotides of the genomes (SNPs) as well as many larger variations, such as deletions, insertions and copy number variations. Any of these may cause alterations in an individual's traits, or phenotype, which can be anything from disease risk to physical properties such as height. Around the year 2000, prior to the introduction of GWA studies, the primary method of investigation was through inheritance studies of genetic linkage in families. This approach had proven highly useful towards single gene disorders. However, for common and complex diseases the results of genetic linkage studies proved hard to reproduce. A suggested alternative to linkage studies was the genetic association study. This study type asks if the allele of a genetic variant is found more often than expected in individuals with the phenotype of interest (e.g. with the disease being studied). Early calculations on statistical power indicated that this approach could be better than linkage studies at detecting weak genetic effects.
In addition to the conceptual framework several additional factors enabled the GWA studies. One was the advent of biobanks, which are repositories of human genetic material that greatly reduced the cost and difficulty of collecting sufficient numbers of biological specimens for study. Another was the International HapMap Project, which, from 2003 identified a majority of the common SNPs interrogated in a GWA study. The haploblock structure identified by HapMap project also allowed the focus on the subset of SNPs that would describe most of the variation. Also the development of the methods to genotype all these SNPs using genotyping arrays was an important prerequisite.
Methods
The most common approach of GWA studies is the case-control setup, which compares two large groups of individuals, one healthy control group and one case group affected by a disease. All individuals in each group are typically genotyped at common known SNPs. The exact number of SNPs depends on the genotyping technology, but are typically one million or more. For each of these SNPs it is then investigated if the allele frequency is significantly altered between the case and the control group. In such setups, the fundamental unit for reporting effect sizes is the odds ratio. The odds ratio is the ratio of two odds, which in the context of GWA studies are the odds of case for individuals having a specific allele and the odds of case for individuals who do not have that same allele.
Example: suppose that there are two alleles, T and C. The number of individuals in the case group having allele T is represented by 'A' and the number of individuals in the control group having allele T is represented by 'B'. Similarly, the number of individuals in the case group having allele C is represented by 'X' and the number of individuals in the control group having allele C is represented by 'Y'. In this case the odds ratio for allele T is A:B (meaning 'A to B', in standard odds terminology) divided by X:Y, which in mathematical notation is simply (A/B)/(X/Y).
When the allele frequency in the case group is much higher than in the control group, the odds ratio is higher than 1, and vice versa for lower allele frequency. Additionally, a P-value for the significance of the odds ratio is typically calculated using a simple chi-squared test. Finding odds ratios that are significantly different from 1 is the objective of the GWA study because this shows that a SNP is associated with disease. Because so many variants are tested, it is standard practice to require the p-value to be lower than to consider a variant significant.
Variations on the case-control approach. A common alternative to case-control GWA studies is the analysis of quantitative phenotypic data, e.g. height or biomarker concentrations or even gene expression. Likewise, alternative statistics designed for dominance or recessive penetrance patterns can be used. Calculations are typically done using bioinformatics software such as SNPTEST and PLINK, which also include support for many of these alternative statistics. GWAS focuses on the effect of individual SNPs. However, it is also possible that complex interactions among two or more SNPs (epistasis) might contribute to complex diseases. Due to the potentially exponential number of interactions, detecting statistically significant interactions in GWAS data is both computationally and statistically challenging. This task has been tackled in existing publications that use algorithms inspired from data mining. Moreover, the researchers try to integrate GWA data with other biological data such as protein-protein interaction network to extract more informative results. Despite the previously perceived challenge posed by the vast number of SNP combinations, a recent study has successfully unveiled complete epistatic maps at a gene-level resolution in plants/Arabidopsis thaliana
A key step in the majority of GWA studies is the imputation of genotypes at SNPs not on the genotype chip used in the study. This process greatly increases the number of SNPs that can be tested for association, increases the power of the study, and facilitates meta-analysis of GWAS across distinct cohorts. Genotype imputation is carried out by statistical methods that impute genotypic data to a set of reference panel of haplotypes, which typically have been densely genotyped using whole-genome sequencing. These methods take advantage of sharing of haplotypes between individuals over short stretches of sequence to impute alleles. Existing software packages for genotype imputation include IMPUTE2, Minimac, Beagle and MaCH.
In addition to the calculation of association, it is common to take into account any variables that could potentially confound the results. Sex, age, and ancestry are common examples of confounding variables. Moreover, it is also known that many genetic variations are associated with the geographical and historical populations in which the mutations first arose. Because of this association, studies must take account of the geographic and ethnic background of participants by controlling for what is called population stratification. If they did not do so, the studies could produce false positive results.
After odds ratios and P-values have been calculated for all SNPs, a common approach is to create a Manhattan plot. In the context of GWA studies, this plot shows the negative logarithm of the P-value as a function of genomic location. Thus the SNPs with the most significant association stand out on the plot, usually as stacks of points because of haploblock structure. Importantly, the P-value threshold for significance is corrected for multiple testing issues. The exact threshold varies by study, but the conventional genome-wide significance threshold is to be significant in the face of hundreds of thousands to millions of tested SNPs. GWA studies typically perform the first analysis in a discovery cohort, followed by validation of the most significant SNPs in an independent validation cohort.
Results
Attempts have been made at creating comprehensive catalogues of SNPs that have been identified from GWA studies. As of 2009, SNPs associated with diseases are numbered in the thousands.
The first GWA study, conducted in 2005, compared 96 patients with age-related macular degeneration (ARMD) with 50 healthy controls. It identified two SNPs with significantly altered allele frequency between the two groups. These SNPs were located in the gene encoding complement factor H, which was an unexpected finding in the research of ARMD. The findings from these first GWA studies have subsequently prompted further functional research towards therapeutical manipulation of the complement system in ARMD.
Another landmark publication in the history of GWA studies was the Wellcome Trust Case Control Consortium (WTCCC) study, the largest GWA study ever conducted at the time of its publication in 2007. The WTCCC included 14,000 cases of seven common diseases (~2,000 individuals for each of coronary heart disease, type 1 diabetes, type 2 diabetes, rheumatoid arthritis, Crohn's disease, bipolar disorder, and hypertension) and 3,000 shared controls. This study was successful in uncovering many genes associated with these diseases.
Since these first landmark GWA studies, there have been two general trends. One has been towards larger and larger sample sizes. In 2018, several genome-wide association studies are reaching a total sample size of over 1 million participants, including 1.1 million in a genome-wide study of educational attainment follow by another in 2022 with 3 million individuals and a study of insomnia containing 1.3 million individuals. The reason is the drive towards reliably detecting risk-SNPs that have smaller effect sizes and lower allele frequency. Another trend has been towards the use of more narrowly defined phenotypes, such as blood lipids, proinsulin or similar biomarkers. These are called intermediate phenotypes, and their analyses may be of value to functional research into biomarkers.
A variation of GWAS uses participants that are first-degree relatives of people with a disease. This type of study has been named genome-wide association study by proxy (GWAX).
A central point of debate on GWA studies has been that most of the SNP variations found by GWA studies are associated with only a small increased risk of the disease, and have only a small predictive value. The median odds ratio is 1.33 per risk-SNP, with only a few showing odds ratios above 3.0. These magnitudes are considered small because they do not explain much of the heritable variation. This heritable variation is estimated from heritability studies based on monozygotic twins. For example, it is known that 40% of variance in depression can be explained by hereditary differences, but GWA studies only account for a minority of this variance.
Clinical applications and examples
A challenge for future successful GWA study is to apply the findings in a way that accelerates drug and diagnostics development, including better integration of genetic studies into the drug-development process and a focus on the role of genetic variation in maintaining health as a blueprint for designing new drugs and diagnostics. Several studies have looked into the use of risk-SNP markers as a means of directly improving the accuracy of prognosis. Some have found that the accuracy of prognosis improves, while others report only minor benefits from this use. Generally, a problem with this direct approach is the small magnitudes of the effects observed. A small effect ultimately translates into a poor separation of cases and controls and thus only a small improvement of prognosis accuracy. An alternative application is therefore the potential for GWA studies to elucidate pathophysiology.
Hepatitis C treatment
One such success is related to identifying the genetic variant associated with response to anti-hepatitis C virus treatment. For genotype 1 hepatitis C treated with Pegylated interferon-alpha-2a or Pegylated interferon-alpha-2b combined with ribavirin, a GWA study has shown that SNPs near the human IL28B gene, encoding interferon lambda 3, are associated with significant differences in response to the treatment. A later report demonstrated that the same genetic variants are also associated with the natural clearance of the genotype 1 hepatitis C virus. These major findings facilitated the development of personalized medicine and allowed physicians to customize medical decisions based on the patient's genotype.
eQTL, LDL and cardiovascular disease
The goal of elucidating pathophysiology has also led to increased interest in the association between risk-SNPs and the gene expression of nearby genes, the so-called expression quantitative trait loci (eQTL) studies. The reason is that GWAS studies identify risk-SNPs, but not risk-genes, and specification of genes is one step closer towards actionable drug targets. As a result, major GWA studies by 2011 typically included extensive eQTL analysis. One of the strongest eQTL effects observed for a GWA-identified risk SNP is the SORT1 locus. Functional follow up studies of this locus using small interfering RNA and gene knock-out mice have shed light on the metabolism of low-density lipoproteins, which have important clinical implications for cardiovascular disease.
Atrial fibrillation
For example, a meta-analysis accomplished in 2018 revealed the discovery of 70 new loci associated with atrial fibrillation. It has been identified different variants associated with transcription factor coding-genes, such as TBX3 and TBX5, NKX2-5 o PITX2, which are involved in cardiac conduction regulation, in ionic channel modulation and cardiac development. It was also identified new genes involved in tachycardia (CASQ2) or associated with alteration of cardiac muscle cell communication (PKP2).
Schizophrenia
Research using a High-Precision Protein Interaction Prediction (HiPPIP) computational model that discovered 504 new protein-protein interactions (PPIs) associated with genes linked to schizophrenia. While the evidence supporting the genetic basis of schizophrenia is not controversial, one study found that 25 candidate schizophrenia genes discovered from GWAS had little association with schizophrenia, demonstrating that GWAS alone may be insufficient to identify candidate genes.
Pain susceptibility
Another group of researchers conducted a joint analysis of GWAS summary statistics from seventeen pain susceptibility traits in the UK Biobank and revealed 99 genome-wide significant risk loci, among which 34 loci were new. Also, with leave-one-trait-out meta-analyses these loci were grouped in four categories: Loci associated with nearly all pain-related traits, associated with a single trait, associated with multiple forms of skeletomuscular pain and with headache-related pain.
Moreover, 664 genes were mapped to the 99 loci by genomic proximity, eQTLs and chromatin interaction, where 15% of these genes showed differential expression in individuals with acute or chronic pain compared to healthy individuals.
Conservation applications
Population level GWA studies may be used to identify adaptive genes to help evaluate ability of species to adapt to changing environmental conditions as the global climate becomes warmer. This could help determine extirpation risk for species and could therefore be an important tool for conservation planning. Utilizing GWA studies to determine adaptive genes could help elucidate the relationship between neutral and adaptive genetic diversity.
Agricultural applications
Plant growth stages and yield components
GWA studies act as an important tool in plant breeding. With large genotyping and phenotyping data, GWAS are powerful in analyzing complex inheritance modes of traits that are important yield components such as number of grains per spike, weight of each grain and plant structure. In a study on GWAS in spring wheat, GWAS have revealed a strong correlation of grain production with booting data, biomass and number of grains per spike. GWA study is also a success in study genetic architecture of complex traits in rice.
Plant pathogens
The emergences of plant pathogens have posed serious threats to plant health and biodiversity. Under this consideration, identification of wild types that have the natural resistance to certain pathogens could be of vital importance. Furthermore, we need to predict which alleles are associated with the resistance. GWA studies is a powerful tool to detect the relationships of certain variants and the resistance to the plant pathogen, which is beneficial for developing new pathogen-resisted cultivars.
Chicken
The first GWA study in chickens was done by Abasht and Lamont in 2007. This GWA was used to study the fatness trait in F2 population found previously. Significantly related SNPs were found are on 10 chromosomes (1, 2, 3, 4, 7, 8, 10, 12, 15 and 27).
Limitations
GWA studies have several issues and limitations that can be taken care of through proper quality control and study setup. Lack of well defined case and control groups, insufficient sample size, control for population stratification are common problems. On the statistical issue of multiple testing, it has been noted that "the GWA approach can be problematic because the massive number of statistical tests performed presents an unprecedented potential for false-positive results". This is why all modern GWAS use a very low p-value threshold. In addition to easily correctible problems such as these, some more subtle but important issues have surfaced. A high-profile GWA study that investigated individuals with very long life spans to identify SNPs associated with longevity is an example of this. The publication came under scrutiny because of a discrepancy between the type of genotyping array in the case and control group, which caused several SNPs to be falsely highlighted as associated with longevity. The study was subsequently retracted, but a modified manuscript was later published. Now, many GWAS control for genotyping array. If there are substantial differences between groups on the type of genotyping array, as with any confounder, GWA studies could result in a false positive. Another consequence is that such studies are unable to detect the contribution of very rare mutations not included in the array or able to be imputed.
Additionally, GWA studies identify candidate risk variants for the population from which their analysis is performed, and with most GWA studies historically stemming from European databases, there is a lack of translation of the identified risk variants to other non-European populations. For instance, GWA studies for diseases like Alzheimer's disease have been conducted primarily in Caucasian populations, which does not give adequate insight in other ethnic populations, including African Americans or East Asians. Alternative strategies suggested involve linkage analysis. More recently, the rapidly decreasing price of complete genome sequencing have also provided a realistic alternative to genotyping array-based GWA studies. High-throughput sequencing does have potential to side-step some of the shortcomings of non-sequencing GWA. Cross-trait assortative mating can inflate estimates of genetic phenotype similarity.
Fine-mapping
Genotyping arrays designed for GWAS rely on linkage disequilibrium to provide coverage of the entire genome by genotyping a subset of variants. Because of this, the reported associated variants are unlikely to be the actual causal variants. Associated regions can contain hundreds of variants spanning large regions and encompassing many different genes, making the biological interpretation of GWAS loci more difficult. Fine-mapping is a process to refine these lists of associated variants to a credible set most likely to include the causal variant.
Fine-mapping requires all variants in the associated region to have been genotyped or imputed (dense coverage), very stringent quality control resulting in high-quality genotypes, and large sample sizes sufficient in separating out highly correlated signals. There are several different methods to perform fine-mapping, and all methods produce a posterior probability that a variant in that locus is causal. Because the requirements are often difficult to satisfy, there are still limited examples of these methods being more generally applied.
See also
Association mapping
Transcriptome-wide association study
Epidemiology
Genetic diversity
Gene–environment interaction
Genomics
Linkage disequilibrium
Molecular epidemiology
Polygenic score
Population genetics
Genetic epidemiology
Common disease-common variant hypothesis
Microbiome-wide association study
Conservation biology
WGAViewer tool designed to help interpret the results generated from a genome wide association study
References
External links
Genotype-phenotype interaction software tools and databases on omicX
Statistical Methods for the Analysis of Genome-Wide Association Studies [video lecture series]
Whole genome association studies — by the National Human Genome Research Institute
GWAS Central — a central database of summary-level genetic association findings
Consortia of genome-wide association studies (GWAS) — by Bennett SN, Caporaso, NE, et al.
PLINK — whole genome association analysis toolset
ENCODE threads explorer Impact of functional information on understanding variation. Nature (journal)
Genetic epidemiology
Genetics studies
Human genome projects
Personalized medicine | Genome-wide association study | [
"Biology"
] | 4,630 | [
"Human genome projects",
"Genome projects"
] |
11,810,505 | https://en.wikipedia.org/wiki/Polymerase%20cycling%20assembly | Polymerase cycling assembly (or PCA, also known as Assembly PCR) is a method for the assembly of large DNA oligonucleotides from shorter fragments. The process uses the same technology as PCR, but takes advantage of DNA hybridization and annealing as well as DNA polymerase to amplify a complete sequence of DNA in a precise order based on the single stranded oligonucleotides used in the process. It thus allows for the production of synthetic genes and even entire synthetic genomes.
PCA principles
Much like how primers are designed such that there is a forward primer and a reverse primer capable of allowing DNA polymerase to fill the entire template sequence, PCA uses the same technology but with multiple oligonucleotides. While in PCR the customary size of oligonucleotides used is 18 base pairs, in PCA lengths of up to 50 are used to ensure uniqueness and correct hybridization.
Each oligonucleotide is designed to be either part of the top or bottom strand of the target sequence. As well as the basic requirement of having to be able to tile the entire target sequence, these oligonucleotides must also have the usual properties of similar melting temperatures, hairpin free, and not too GC rich to avoid the same complications as PCR.
During the polymerase cycles, the oligonucleotides anneal to complementary fragments and then are filled in by polymerase. Each cycle thus increases the length of various fragments randomly depending on which oligonucleotides find each other. It is critical that there is complementarity between all the fragments in some way or a final complete sequence will not be produced as polymerase requires a template to follow.
After this initial construction phase, additional primers encompassing both ends are added to perform a regular PCR reaction, amplifying the target sequence away from all the shorter incomplete fragments. A gel purification can then be used to identify and isolate the complete sequence.
Typical reaction
A typical reaction consists of oligonucleotides ~50 base pairs long each overlapping by about 20 base pairs. The reaction with all the oligonucleotides is then carried out for ~30 cycles followed by an additional 23 cycles with the end primers.
Gibson assembly
A modification of this method, Gibson assembly, described by Gibson et al. allows for single-step isothermal assembly of DNA with up to several hundreds kb. By using T5 exonuclease to 'chew back' complementary ends, an overlap of about 40bp can be created. The reaction takes place at 50 °C, a temperature where the T5 exonuclease is unstable. After a short timestep it is degraded, the overlaps can anneal and be ligated. Cambridge University IGEM team made a video describing the process. Ligation independent cloning (LIC) is a new variant of the method for compiling several DNA pieces together and needing only exonuclease enzyme for the reaction.
References
Amplifiers
Genetic engineering
Genetics techniques
Laboratory techniques | Polymerase cycling assembly | [
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"Technology",
"Engineering",
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"Genetics techniques",
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"Genetic engineering",
"nan",
"Molecular biology",
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3,003,434 | https://en.wikipedia.org/wiki/Valiant%E2%80%93Vazirani%20theorem | The Valiant–Vazirani theorem is a theorem in computational complexity theory stating that if there is a polynomial time algorithm for Unambiguous-SAT, then NP = RP. It was proven by Leslie Valiant and Vijay Vazirani in their paper titled NP is as easy as detecting unique solutions published in 1986.
The Valiant–Vazirani theorem implies that the Boolean satisfiability problem, which is NP-complete, remains a computationally hard problem even if the input instances are promised to have at most one satisfying assignment.
Proof outline
Unambiguous-SAT is the promise problem of deciding whether a given Boolean formula that has at most one satisfying assignment is unsatisfiable or has exactly one satisfying assignment. In the first case, an algorithm for Unambiguous-SAT should reject, and in the second it should accept the formula.
If the formula has more than one satisfying assignment, then there is no condition on the behavior of the algorithm.
The promise problem Unambiguous-SAT can be decided by a nondeterministic Turing machine that has at most one accepting computation path, thus it belongs to the promise version of the complexity class UP (the class UP as such is only defined for languages).
The proof of the Valiant–Vazirani theorem consists of a probabilistic reduction that given a formula F in n variables, outputs a sequence of formulas G0,...,Gn such that:
Every satisfying assignment of any Gi also satisfies F. Thus, if F is unsatisfiable, then all Gi, i ≤ n, are unsatisfiable.
If F is satisfiable, then with probability at least 1/4, some Gi has a unique satisfying assignment.
The idea of the reduction is to successively intersect the solution space of the formula F with n random linear hyperplanes in .
As a consequence (not needed for the NP = RP argument, but of independent interest), if we choose one of the Gi at random, we obtain a randomized reduction with one-sided error from SAT to Unambiguous-SAT that succeeds with probability at least Ω(1/n). That is, if F is unsatisfiable, the output formula is always unsatisfiable, and if F is satisfiable, then the output formula has a unique satisfying assignment with probability Ω(1/n).
Now, assuming Unambiguous-SAT is solvable by a polynomial time algorithm A, we obtain an RP algorithm for SAT by running A on Gi for each i ≤ n. If F is unsatisfiable, then A rejects all Gi as they are unsatisfiable, whereas if F is satisfiable, then A accepts some Gi with probability at least 1/4. (We can improve the acceptance probability by repeating the reduction several times.)
More generally, this argument shows unconditionally that NP is included in RPpromiseUP.
An alternative proof is based on the isolation lemma by Mulmuley, Vazirani, and Vazirani. They consider a more general setting, and applied to the setting here this gives an isolation probability of only .
References
Structural complexity theory
Theorems in computational complexity theory | Valiant–Vazirani theorem | [
"Mathematics"
] | 674 | [
"Theorems in computational complexity theory",
"Theorems in discrete mathematics"
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3,003,448 | https://en.wikipedia.org/wiki/Angular%20diameter%20distance | In astronomy, angular diameter distance is a distance (in units of length) defined in terms of an object's physical size (also in units of length), , and its angular size (necessarily in radians), , as viewed from Earth:
Cosmology dependence
The angular diameter distance depends on the assumed cosmology of the universe. The angular diameter distance to an object at redshift, , is expressed in terms of the comoving distance, as:
where is the FLRW coordinate defined as:
where is the curvature density and is the value of the Hubble parameter today.
In the currently favoured geometric model of our Universe, the "angular diameter distance" of an object is a good approximation to the "real distance", i.e. the proper distance when the light left the object.
Angular size redshift relation
The angular size redshift relation describes the relation between the angular size observed on the sky of an object of given physical size, and the object's redshift from Earth (which is related to its distance, , from Earth). In a Euclidean geometry the relation between size on the sky and distance from Earth would simply be given by the equation:
where is the angular size of the object on the sky, is the size of the object and is the distance to the object. Where is small this approximates to:
However, in the ΛCDM model, the relation is more complicated. In this model, objects at redshifts greater than about 1.5 appear larger on the sky with increasing redshift.
This is related to the angular diameter distance, which is the distance an object is calculated to be at from and , assuming the Universe is Euclidean.
The Mattig relation yields the angular-diameter distance, , as a function of redshift z for a universe with ΩΛ = 0. is the present-day value of the deceleration parameter, which measures the deceleration of the expansion rate of the Universe; in the simplest models, corresponds to the case where the Universe will expand forever, to closed models which will ultimately stop expanding and contract, corresponds to the critical case – Universes which will just be able to expand to infinity without re-contracting.
This formula however is invalid, since the value of Λ ≫ 0 and ≪ 0.
Angular diameter turnover point
The angular diameter distance reaches a maximum at a redshift (in the ΛCDM model, this occurs at ), such that the slope of changes sign at , or , . In reference to its appearance when plotted, is sometimes referred to as the turnover point. At this point also . Practically, this means that if we look at objects at increasing redshift (and thus objects that are increasingly far away) those at greater redshift will span a smaller angle on the sky only until , above which the objects will begin to span greater angles on the sky at greater redshift. The turnover point seems paradoxical because it contradicts our intuition that the farther something is, the smaller it will appear.
The turnover point occurs because of the expansion of the universe and because we observe distant galaxies as they were in the past. Because the universe is expanding, a pair of distant objects that are now distant from each other were closer to each other at earlier times. Because the speed of light is finite, the light reaching us from this pair of objects must have left them long ago when they were nearer to one another and spanned a larger angle on the sky. The turnover point can therefore tell us about the rate of expansion of the universe (or the relationship between the expansion rate and the speed of light if we do not assume the latter to be constant).
See also
Distance measure
Standard ruler
References
External links
iCosmos: Cosmology Calculator (With Graph Generation )
Physical quantities
Distance
Equations of astronomy | Angular diameter distance | [
"Physics",
"Astronomy",
"Mathematics"
] | 782 | [
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3,003,483 | https://en.wikipedia.org/wiki/Silicotungstic%20acid | Silicotungstic acid or tungstosilicic acid is a heteropoly acid with the chemical formula . It forms hydrates . In freshly prepared samples, n is approximately 29, but after prolonged desiccation, n = 6. It is a white solid although impure samples appear yellow. It is used as a catalyst in the chemical industry.
Applications
Silicotungstic acid is used to manufacture ethyl acetate by the alkylation of acetic acid by ethylene:
It has also been commercialized for the oxidation of ethylene to acetic acid:
This route is claimed as a "greener" than methanol carbonylation. The heteropoly acid is dispersed on silica gel at 20-30 wt% to maximize catalytic ability.
It has also recently been proposed as a mediator in production of hydrogen through electrolysis of water by a process that would reduce the danger of explosion while allowing efficient hydrogen production at low current densities, conducive to hydrogen production using renewable energy.
Synthesis and structure
The free acid is produced by combining sodium silicate and tungsten trioxide followed treatment of the mixture with hydrochloric acid. The polyoxo cluster adopts a Keggin structure, with Td point group symmetry.
Hazards
Silicotungstic acid is an irritating and odorless substance.
References
Inorganic silicon compounds
Tungstic acids
Heteropoly acids
Coordination complexes
Mineral acids | Silicotungstic acid | [
"Chemistry"
] | 297 | [
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"Coordination complexes",
"Coordination chemistry",
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3,003,553 | https://en.wikipedia.org/wiki/Noether%20normalization%20lemma | In mathematics, the Noether normalization lemma is a result of commutative algebra, introduced by Emmy Noether in 1926. It states that for any field k, and any finitely generated commutative k-algebra A, there exist elements y1, y2, ..., yd in A that are algebraically independent over k and such that A is a finitely generated module over the polynomial ring S = k[y1, y2, ..., yd]. The integer d is equal to the Krull dimension of the ring A; and if A is an integral domain, d is also the transcendence degree of the field of fractions of A over k.
The theorem has a geometric interpretation. Suppose A is the coordinate ring of an affine variety X, and consider S as the coordinate ring of a d-dimensional affine space . Then the inclusion map induces a surjective finite morphism of affine varieties : that is, any affine variety is a branched covering of affine space.
When k is infinite, such a branched covering map can be constructed by taking a general projection from an affine space containing X to a d-dimensional subspace.
More generally, in the language of schemes, the theorem can equivalently be stated as: every affine k-scheme (of finite type) X is finite over an affine n-dimensional space. The theorem can be refined to include a chain of ideals of R (equivalently, closed subsets of X) that are finite over the affine coordinate subspaces of the corresponding dimensions.
The Noether normalization lemma can be used as an important step in proving Hilbert's Nullstellensatz, one of the most fundamental results of classical algebraic geometry. The normalization theorem is also an important tool in establishing the notions of Krull dimension for k-algebras.
Proof
Theorem. (Noether Normalization Lemma) Let k be a field and be a finitely generated k-algebra. Then for some integer d, , there exist algebraically independent over k such that A is finite (i.e., finitely generated as a module) over (the integer d is then equal to the Krull dimension of A). If A is an integral domain, then d is also the transcendence degree of the field of fractions of A over k.
The following proof is due to Nagata and appears in Mumford's red book. A more geometric proof is given on page 127 of the red book.
Proof: We shall induct on m. Case is and there is nothing to prove. Assume . Then as k-algebras, where is some ideal. Since is a PID (it is a Euclidean domain), . If we are done, so assume . Let e be the degree of f. Then A is generated, as a k-vector space, by . Thus A is finite over k. Assume now . If the are algebraically independent, then by setting , we are done. If not, it is enough to prove the claim that there is a k-subalgebra S of A that is generated by elements, such that A is finite over S. Indeed, by the inductive hypothesis, we can find, for some integer d, , algebraically independent elements of S such that S is finite over . Since A is finite over S, and S is finite over , we obtain the desired conclusion that A is finite over .
To prove the claim, we assume by hypothesis that the are not algebraically independent, so that there is a nonzero polynomial f in m variables over k such that
.
Given an integer r which is determined later, set
and, for simplification of notation, write
Then the preceding reads:
Now, if is a monomial appearing in the left-hand side of the above equation, with coefficient , the highest term in after expanding the product looks like
.
Whenever the above exponent agrees with the highest exponent produced by some other monomial, it is possible that the highest term in of will not be of the above form, because it may be affected by cancellation. However, if r is large enough (e.g., we can set ), then each encodes a unique base r number, so this does not occur. For such an r, let be the coefficient of the unique monomial of f of multidegree for which the quantity is maximal. Multiplication of by gives an integral dependence equation of over , i.e., is integral over S. Moreover, because , A is in fact finite over S. This completes the proof of the claim, so we are done with the first part.
Moreover, if A is an integral domain, then d is the transcendence degree of its field of fractions. Indeed, A and the polynomial ring have the same transcendence degree (i.e., the degree of the field of fractions) since the field of fractions of A is algebraic over that of S (as A is integral over S) and S has transcendence degree d. Thus, it remains to show the Krull dimension of S is d. (This is also a consequence of dimension theory.) We induct on d, with the case being trivial. Since is a chain of prime ideals, the dimension is at least d. To get the reverse estimate, let be a chain of prime ideals. Let . We apply the Noether normalization and get (in the normalization process, we're free to choose the first variable) such that S is integral over T. By the inductive hypothesis, has dimension . By incomparability, is a chain of length and then, in , it becomes a chain of length . Since , we have . Hence, .
Refinement
The following refinement appears in Eisenbud's book, which builds on Nagata's idea:
Geometrically speaking, the last part of the theorem says that for any general linear projection induces a finite morphism (cf. the lede); besides Eisenbud, see also .
Illustrative application: generic freeness
A typical nontrivial application of the normalization lemma is the generic freeness theorem: Let be rings such that is a Noetherian integral domain and suppose there is a ring homomorphism that exhibits as a finitely generated algebra over . Then there is some such that is a free -module.
To prove this, let be the fraction field of . We argue by induction on the Krull dimension of . The base case is when the Krull dimension is ; i.e., ; that is, when there is some such that , so that is free as an -module. For the inductive step, note that is a finitely generated -algebra. Hence by the Noether normalization lemma, contains algebraically independent elements such that is finite over the polynomial ring . Multiplying each by elements of , we can assume are in . We now consider:
Now may not be finite over , but it will become finite after inverting a single element as follows. If is an element of , then, as an element of , it is integral over ; i.e., for some in . Thus, some kills all the denominators of the coefficients of and so is integral over . Choosing some finitely many generators of as an -algebra and applying this observation to each generator, we find some such that is integral (thus finite) over . Replace by and then we can assume is finite over .
To finish, consider a finite filtration by -submodules such that for prime ideals (such a filtration exists by the theory of associated primes). For each i, if , by inductive hypothesis, we can choose some in such that is free as an -module, while is a polynomial ring and thus free. Hence, with , is a free module over .
Notes
References
. NB the lemma is in the updating comments.
Further reading
Robertz, D.: Noether normalization guided by monomial cone decompositions. Journal of Symbolic Computation 44(10), 1359–1373 (2009)
Commutative algebra
Algebraic varieties
Lemmas in algebra
Algebraic geometry | Noether normalization lemma | [
"Mathematics"
] | 1,723 | [
"Theorems in algebra",
"Lemmas in algebra",
"Fields of abstract algebra",
"Algebraic geometry",
"Commutative algebra",
"Lemmas"
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3,003,614 | https://en.wikipedia.org/wiki/Bis%282-ethylhexyl%29%20phthalate | Bis(2-ethylhexyl) phthalate (di-2-ethylhexyl phthalate, diethylhexyl phthalate, diisooctyl phthalate, DEHP; incorrectly — dioctyl phthalate, DIOP) is an organic compound with the formula C6H4(CO2C8H17)2. DEHP is the most common member of the class of phthalates, which are used as plasticizers. It is the diester of phthalic acid and the branched-chain 2-ethylhexanol. This colorless viscous liquid is soluble in oil, but not in water.
Production
Di(2-ethylhexyl) phthalate is produced commercially by the reaction of excess 2-ethylhexanol with phthalic anhydride in the presence of an acid catalyst such as sulfuric acid or para-toluenesulfonic acid. It was first produced in commercial quantities in Japan circa 1933 and in the United States in 1939.
DEHP has two stereocenters, located at the carbon atoms carrying the ethyl groups. As a result, it has three distinct stereoisomers, consisting of an (R,R) form, an (S,S) form (diastereomers), and a meso (R, S) form. As most 2-ethylhexanol is produced as a racemic mixture, commercially-produced DEHP is therefore racemic as well, and consists of a 1:1:2 statistical mixture of stereoisomers.
Use
Due to its suitable properties and the low cost, DEHP is widely used as a plasticizer in manufacturing of articles made of PVC. Plastics may contain 1% to 40% of DEHP. It is also used as a hydraulic fluid and as a dielectric fluid in capacitors. DEHP also finds use as a solvent in glowsticks.
Approximately three million tonnes are produced and used annually worldwide.
Manufacturers of flexible PVC articles can choose among several alternative plasticizers offering similar technical properties as DEHP. These alternatives include other phthalates such as diisononyl phthalate (DINP), di-2-propyl heptyl phthalate (DPHP), diisodecyl phthalate (DIDP), and non-phthalates such as 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH), dioctyl terephthalate (DOTP), and citrate esters.
Environmental exposure
DEHP is a component of many household items, including tablecloths, floor tiles, shower curtains, garden hoses, rainwear, dolls, toys, shoes, medical tubing, furniture upholstery, and swimming pool liners. DEHP is an indoor air pollutant in homes and schools. Common exposures come from the use of DEHP as a fragrance carrier in cosmetics, personal care products, laundry detergents, colognes, scented candles, and air fresheners.
The most common exposure to DEHP comes through food with an average consumption of 0.25 milligrams per day. It can also leach into a liquid that comes in contact with the plastic; it extracts faster into nonpolar solvents (e.g. oils and fats in foods packed in PVC). Fatty foods that are packaged in plastics that contain DEHP are more likely to have higher concentrations such as milk products, fish or seafood, and oils. The US FDA therefore permits use of DEHP-containing packaging only for foods that primarily contain water.
DEHP can leach into drinking water from discharges from rubber and chemical factories; The US EPA limits for DEHP in drinking water is 6 ppb. It is also commonly found in bottled water, but unlike tap water, the EPA does not regulate levels in bottled water. DEHP levels in some European samples of milk, were found at 2000 times higher than the EPA Safe Drinking Water limits (12,000 ppb). Levels of DEHP in some European cheeses and creams were even higher, up to 200,000 ppb, in 1994. Additionally, workers in factories that utilize DEHP in production experience greater exposure. The U.S. agency OSHA's limit for occupational exposure is 5 mg/m3 of air.
Use in medical devices
DEHP is the most common phthalate plasticizer in medical devices such as intravenous tubing and bags, IV catheters, nasogastric tubes, dialysis bags and tubing, blood bags and transfusion tubing, and air tubes. DEHP makes these plastics softer and more flexible and was first introduced in the 1940s in blood bags. For this reason, concern has been expressed about leachates of DEHP transported into the patient, especially for those requiring extensive infusions or those who are at the highest risk of developmental abnormalities, e.g. newborns in intensive care nursery settings, hemophiliacs, kidney dialysis patients, neonates, premature babies, lactating, and pregnant women. According to the European Commission Scientific Committee on Health and Environmental Risks (SCHER), exposure to DEHP may exceed the tolerable daily intake in some specific population groups, namely people exposed through medical procedures such as kidney dialysis. The American Academy of Pediatrics has advocated not to use medical devices that can leach DEHP into patients and, instead, to resort to DEHP-free alternatives. In July 2002, the U.S. FDA issued a Public Health Notification on DEHP, stating in part, "We recommend considering such alternatives when these high-risk procedures are to be performed on male neonates, pregnant women who are carrying male fetuses, and peripubertal males" noting that the alternatives were to look for non-DEHP exposure solutions; they mention a database of alternatives. The CBC documentary The Disappearing Male raised concerns about sexual development in male fetal development, miscarriage, and as a cause of dramatically lower sperm counts in men. A review article in 2010 in the Journal of Transfusion Medicine showed a consensus that the benefits of lifesaving treatments with these devices far outweigh the risks of DEHP leaching out of these devices. Although more research is needed to develop alternatives to DEHP that gives the same benefits of being soft and flexible, which are required for most medical procedures, if a procedure requires one of these devices and if patient is at high risk to suffer from DEHP then a DEHP alternative should be considered if medically safe.
Metabolism
DEHP hydrolyzes to mono-ethylhexyl phthalate (MEHP) and subsequently to phthalate salts. The released alcohol is susceptible to oxidation to the aldehyde and carboxylic acid.
Effects on living organisms
Toxicity
The acute toxicity of DEHP is low in animal models: 30 g/kg in rats (oral) and 24 g/kg in rabbits (dermal). Concerns instead focus on its potential as an endocrine disruptor.
Endocrine disruption
DEHP, along with other phthalates, is believed to cause endocrine disruption in males, through its action as an androgen antagonist, and may have lasting effects on reproductive function, for both childhood and adult exposures. Prenatal phthalate exposure has been shown to be associated with lower levels of reproductive function in adolescent males. In another study, airborne concentrations of DEHP at a PVC pellet plant were significantly associated with a reduction in sperm motility and chromatin DNA integrity. Additionally, the authors noted the daily intake estimates for DEHP were comparable to the general population, indicating a "high percentage of men are exposed to levels of DEHP that may affect sperm motility and chromatin DNA integrity". The claims have received support by a study using dogs as a "sentinel species to approximate human exposure to a selection of chemical mixtures present in the environment". The authors analyzed the concentration of DEHP and other common chemicals such as PCBs in testes from dogs from five different world regions. The results showed that regional differences in concentration of the chemicals are reflected in dog testes and that pathologies such as tubule atrophy and germ cells were more prevalent in testes of dogs from regions with higher concentrations.
Development
Numerous studies of DEHP have shown changes in sexual function and development in mice and rats. DEHP exposure during pregnancy has been shown to disrupt placental growth and development in mice, resulting in higher rates of low birthweight, premature birth, and fetal loss. In a separate study, exposure of neonatal mice to DEHP through lactation caused hypertrophy of the adrenal glands and higher levels of anxiety during puberty. In another study, pubertal administration of higher-dose DEHP delayed puberty in rats, reduced testosterone production, and inhibited androgen-dependent development; low doses showed no effect.
Obesity
When DEHP is ingested intestinal lipases convert it to MEHP, which then is absorbed. MEHP is suspected to have an obesogenic effect. Rodent studies and human studies have shown DEHP to be a possible disruptor of thyroid function, which plays a key role in energy balance and metabolism. Exposure to DEHP has been associated with lower plasma thyroxine levels and decreased uptake of iodine in thyroid follicular cells. Previous studies have shown that slight changes in thyroxine levels can have dramatic effects on resting energy expenditure, similar to that of patients with hypothyroidism, which has been shown to cause increased weight gain in those study populations.
Cardiotoxicity
Even at relatively low doses of DEHP, cardiovascular reactivity was significantly affected in mice. A clinically relevant dose and duration of exposure to DEHP has been shown to have a significant impact on the behavior of cardiac cells in culture. This includes an uncoupling effect that leads to irregular rhythms in vitro. Untreated cells had fast conduction velocity, along with homogenous activation wave fronts and synchronized beating. Cells treated with DEHP exhibited fractured wave fronts with slow propagation speeds. This is observed in conjunction with a significant decrease in the amount of expression and instability of gap junctional connexin proteins, specifically connexin-43, in cardiomyocytes treated with DEHP.
The decrease in expression and instability of connexin-43 may be due to the down regulation of tubulin and kinesin genes, and the alteration of microtubule structure, caused by DEHP; all of which are responsible for the transport of protein products. Also, DEHP caused down regulation of several growth factors, such as angiotensinogen, transforming growth factor-beta, vascular endothelial growth factor C and A, and endothelial-1. The DEHP-induced down regulation of these growth factors may also contribute to the reduced expression and instability of connexin-43.
DEHP has also been shown, in vitro using cardiac muscle cells, to cause activation of PPAR-alpha gene, which is a key regulator in lipid metabolism and peroxisome proliferation; both of which can be involved in atherosclerosis and hyperlipidemia, which are precursors of cardiovascular disease.
Once metabolized into MEHP, the molecule has been shown to lengthen action potential duration and slow epicardial conduction velocity in Langendorff perfused rodent hearts.
Other health effects
Studies in mice have shown other adverse health effects due to DEHP exposure. Ingestion of 0.01% DEHP caused damage to the blood-testis barrier as well as induction of experimental autoimmune orchitis. There is also a correlation between DEHP plasma levels in women and endometriosis.
DEHP is also a possible cancer causing agent in humans, although human studies remain inconclusive, due to the exposure of multiple elements and limited research. In vitro and rodent studies indicate that DEHP is involved in many molecular events, including increased cell proliferation, decreased apoptosis, oxidative damage, and selective clonal expansion of the initiated cells; all of which take place in multiple sites of the human body.
Government and industry response
Taiwan
In October 2009, Consumers' Foundation, Taiwan (CFCT) published test results that found 5 out of the sampled 12 shoes contained over 0.1% of phthalate plasticizer content, including DEHP, which exceeds the government's Toy Safety Standard (CNS 4797). CFCT recommend that users should first wear socks to avoid direct skin contact.
In May 2011, the illegal use of the plasticizer DEHP in clouding agents for use in food and beverages has been reported in Taiwan. An inspection of products initially discovered the presence of plasticizers. As more products were tested, inspectors found more manufacturers using DEHP and DINP. The Department of Health confirmed that contaminated food and beverages had been exported to other countries and regions, which reveals the widespread prevalence of toxic plasticizers.
European Union
Concerns about chemicals ingested by children when chewing plastic toys prompted the European Commission to order a temporary ban on phthalates in 1999, the decision of which is based on an opinion by the Commission's Scientific Committee on Toxicity, Ecotoxicity and the Environment (CSTEE). A proposal to make the ban permanent was tabled. Until 2004, EU banned the use of DEHP along with several other phthalates (DBP, BBP, DINP, DIDP and DNOP) in toys for young children. In 2005, the Council and the Parliament compromised to propose a ban on three types of phthalates (DINP, DIDP, and DNOP) "in toys and childcare articles which can be placed in the mouth by children". Therefore, more products than initially planned will thus be affected by the directive. In 2008, six substances were considered to be of very high concern (SVHCs) and added to the Candidate List including musk xylene, MDA, HBCDD, DEHP, BBP, and DBP. In 2011, those six substances have been listed for Authorization in Annex XIV of REACH by Regulation (EU) No 143/2011. According to the regulation, phthalates including DEHP, BBP and DBP will be banned from February 2015.
In 2012, Danish Environment Minister Ida Auken announced the ban of DEHP, DBP, DIBP and BBP, pushing Denmark ahead of the European Union which has already started a process of phasing out phthalates. However, it was postponed by two years and would take effect in 2015 and not in December 2013, which was the initial plan. The reason is that the four phthalates are far more common than expected and that producers cannot phase out phthalates as fast as the Ministry of Environment requested.
In 2012, France became the first country in the EU to ban the use of DEHP in pediatrics, neonatal, and maternity wards in hospitals.
DEHP has now been classified as a Category 1B reprotoxin, and is now on the Annex XIV of the European Union's REACH legislation. DEHP has been phased out in Europe under REACH and can only be used in specific cases if an authorization has been granted. Authorizations are granted by the European Commission, after obtaining the opinion of the Committee for Risk Assessment (RAC) and the Committee for Socio-economic Analysis (SEAC) of the European Chemicals Agency (ECHA).
California
DEHP is classified as a "chemical known to the State of California to cause cancer and birth defects or other reproductive harm" (in this case, both) under the terms of Proposition 65.
References
Further reading
External links
FDA Public Health Notification: PVC devices containing the plasticizer DEHP (archived page)
ATSDR ToxFAQs
CDC - NIOSH Pocket Guide to Chemical Hazards
National Pollutant Inventory - DEHP fact sheet
Healthcare without Harm - PVC and DEHP accessed 25 March 2014
Healthcare without Harm: "Weight of the Evidence on DEHP: Exposures are a Cause for Concern, Especially During Medical Care"; 6p-fact sheet, 16 March 2009 accessed 25 March 2014
Spectrum Laboratories Fact Sheet (archived page)
ChemSub Online : Bis(2-ethylhexyl) phthalate -DEHP
Safety Assessment of Di(2-ethylhexyl)phthalate (DEHP) Released from PVC Medical Devices - Center for Devices and Radiological Health U.S. Food and Drug Administration (archived page)
Ester solvents
IARC Group 2B carcinogens
Phthalate esters
Endocrine disruptors
Plasticizers
2-Ethylhexyl esters | Bis(2-ethylhexyl) phthalate | [
"Chemistry"
] | 3,469 | [
"Endocrine disruptors"
] |
3,003,616 | https://en.wikipedia.org/wiki/Freedom%20Toaster | A Freedom Toaster is a public kiosk that will burn copies of free software onto user-provided CDs and DVDs.
History
The original Freedom Toaster project was sponsored by Mark Shuttleworth's Shuttleworth Foundation and built in Perl by Hamish Whittal. It consisted of a number of CD burning facilities (in kiosk form), where members of the public were able to burn copies of free and open-source software onto self-supplied blank CD media.
The project was started as one solution to overcome the difficulty of obtaining Linux and other free and open-source software in South Africa, where the restrictive telecommunications environment makes downloading large software files prohibitively expensive.
There are currently Freedom Toasters at the following locations: Bloemfontein, Cape Town (2), Diepkloof, Durban, East London, Grahamstown, Johannesburg (5), Knysna, Namibia, Pietermaritzburg, Port Elizabeth, Port Shepstone, Potchefstroom, Pretoria (3), Seneca College in Toronto, Stellenbosch, Stockholm, Trivandrum.
Functions
A Freedom Toaster kiosk is placed at a school, library, shopping center or another publicly accessible location. Users bring blank optical discs to the kiosk and select the software that they would like. The kiosk will then burn the selected software onto the users' media.
The name derives from this function. "Freedom" refers to the free and open source software provided. "Toaster" is a term for an optical disc burner.
Purpose
Freedom Toaster kiosks provide a way for computer users in economically disadvantaged regions and areas with limited or no Internet access to get software. By providing this service, the people behind the Freedom Toaster hope to address the issue of the Digital Divide.
Availability
The Freedom Toaster is mostly available in South Africa and is currently supported by the Shuttleworth Foundation. The Foundation is attempting to get others to adopt the idea by providing the tools to help create, support and maintain your own Freedom Toaster. It has also provided seed funding to Brett Simpson of Breadbin Interactive to create a sustainable business model with the idea.
The initiative has also been taken up independently by a company in India - Zyxware Technologies - who has partnered with Free Software Users Group, Thiruvananthapuram to promote Freedom Toasters as a viable method to spread Free Software in India.
References
External links
Freedom Toaster (link broken) Archived – The South African website
Seneca Freedom Toaster
Washington-Lee High School Freedom Toaster
Freedom Toaster Map, archived
Freedom Toaster in India, archived
Free software projects
Vending machines
Information technology organisations based in South Africa | Freedom Toaster | [
"Engineering"
] | 549 | [
"Vending machines",
"Automation"
] |
3,003,710 | https://en.wikipedia.org/wiki/Mobile%20daughter%20card | The mobile daughter card, also known as an MDC or CDC (communications daughter card), is a notebook version of the AMR slot on the motherboard of a desktop computer. It is designed to interface with special Ethernet (EDC), modem (MDC) or bluetooth (BDC) cards.
Intel MDC specification 1.0
In 1999, Intel published a specification for mobile audio/modem daughter cards. The document defines a standard connector (AMP* 3-179397-0), mechanical elements including several form factors, and electrical interface. The 30-pin connector carries power, several audio channels and AC-Link serial data. Up to two AC'97 codecs are supported on such a card.
Several form factors are specified:
45 × 27 mm
45 × 37 mm
55 × 27 mm with RJ11 jack
55 × 37 mm with RJ11 jack
45 × 55 mm
45 × 70 mm
30-pin AMP* 3-179397-0 pinout
See also
Daughter board
External links
intel.com – MDC specification.pdf
Mobile computers
Motherboard expansion slot | Mobile daughter card | [
"Technology"
] | 227 | [
"Computing stubs",
"Computer network stubs"
] |
3,004,242 | https://en.wikipedia.org/wiki/Virokine | Virokines are proteins encoded by some large DNA viruses that are secreted by the host cell and serve to evade the host's immune system. Such proteins are referred to as virokines if they resemble cytokines, growth factors, or complement regulators; the term viroceptor is sometimes used if the proteins resemble cellular receptors. A third class of virally encoded immunomodulatory proteins consists of proteins that bind directly to cytokines. Due to the immunomodulatory properties of these proteins, they have been proposed as potentially therapeutically relevant to autoimmune diseases.
Mechanism
The primary mechanism of virokine interference with immune signaling is thought to be competitive inhibition of the binding of host signaling molecules to their target receptors. Virokines occupy binding sites on host receptors, thereby inhibiting access by signaling molecules. Viroceptors mimic host receptors and thus divert signaling molecules from finding their targets. Cytokine-binding proteins bind to and sequester cytokines, occluding the binding surface through which they interact with receptors. The effect is to attenuate and subvert host immune response.
Discovery
The term "virokine" was coined by National Institutes of Health virologist Bernard Moss. The early 1990s saw several reports of virally encoded proteins with sequence homology to immune proteins, followed by reports of the cowpox and vaccinia viruses directly interfering with key immune regulator IL1B. The first identified virokine was an epidermal growth factor-like protein found in myxoma viruses.
Much of the early work on virokines involved vaccinia virus, which was discovered to secrete proteins that promote proliferation of neighboring cells and block complement immune activity leading to inflammation.
Evolutionary origins
The immunomodulatory proteins, including virokines, in the poxvirus family have been extensively studied in the context of the evolution of the family. Virokines in this family are thought to have been acquired from host genes and from other viruses through horizontal gene transfer. Similar observations have been made in the herpesvirus family; for example, Epstein-Barr virus encodes an interleukin protein with high sequence identity to the human interleukin-10, suggesting a recent evolutionary origin.
References
External links
Cytokines & Cells Online Pathfinder Encyclopaedia
Molecular biology
Virology | Virokine | [
"Chemistry",
"Biology"
] | 489 | [
"Biochemistry",
"Molecular biology"
] |
3,004,495 | https://en.wikipedia.org/wiki/TextAmerica | TextAmerica (TA) was one of the first online photo album or moblog sites that allowed users to upload pictures directly from a digital camera or camera phone or images manipulated with photo editing software to a personal page. Originally a free site, TextAmerica began charging membership fees in July 2006 deleting content uploaded to old free accounts some months after that. It closed in December 2007. The domain name is now being used by a different company and service.
External links
Original announcement - Textamerica goes fee-only, will delete all old, free moblogs from boingboing.net, June 20, 2006
American photography websites | TextAmerica | [
"Technology"
] | 134 | [
"Computing stubs",
"World Wide Web stubs"
] |
3,004,575 | https://en.wikipedia.org/wiki/Callboard%20Network | The Callboard Network was an electronic communication network operated by the University of Alberta for USITT in the late 1980s and early 1990s. Its purpose was to provide a means by which USITT members around the world, but primarily in the US and Canada, could easily communicate amongst each other. As the internet expanded rapidly during this period, it rapidly became obsolete but was an invaluable early resource for the members of the organization.
One notable event which occurred on this network was the creation of the MIDI Show Control standard between January and August 1990. This was done using the 'MIDI Forum' which was set up by Charlie Richmond. Several dozen participants from around the world logged in using a variety of means, including dialing long distance. The unique feature of this group of developers was that they never once met to discuss the evolving standard in person. It has been suggested that this was the first international standard that was created 100% virtually and is notable for that reason.
References
Telecommunications infrastructure | Callboard Network | [
"Technology"
] | 198 | [
"Computing stubs",
"Computer network stubs"
] |
3,004,668 | https://en.wikipedia.org/wiki/Infinite%20regress | Infinite regress is a philosophical concept to describe a series of entities. Each entity in the series depends on its predecessor, following a recursive principle. For example, the epistemic regress is a series of beliefs in which the justification of each belief depends on the justification of the belief that comes before it.
An infinite regress argument is an argument against a theory based on the fact that this theory leads to an infinite regress. For such an argument to be successful, it must demonstrate not just that the theory in question entails an infinite regress but also that this regress is vicious. There are different ways in which a regress can be vicious. The most serious form of viciousness involves a contradiction in the form of metaphysical impossibility. Other forms occur when the infinite regress is responsible for the theory in question being implausible or for its failure to solve the problem it was formulated to solve.
Traditionally, it was often assumed without much argument that each infinite regress is vicious but this assumption has been put into question in contemporary philosophy. While some philosophers have explicitly defended theories with infinite regresses, the more common strategy has been to reformulate the theory in question in a way that avoids the regress. One such strategy is foundationalism, which posits that there is a first element in the series from which all the other elements arise but which is not itself explained this way. Another way is coherentism, which is based on a holistic explanation that usually sees the entities in question not as a linear series but as an interconnected network.
Infinite regress arguments have been made in various areas of philosophy. Famous examples include the cosmological argument and Bradley's regress.
Definition
An infinite regress is an infinite series of entities governed by a recursive principle that determines how each entity in the series depends on or is produced by its predecessor. This principle can often be expressed in the following form: X is F because X stands in R to Y and Y is F. X and Y stand for objects, R stands for a relation and F stands for a property in the widest sense. In the epistemic regress, for example, a belief is justified because it is based on another belief that is justified. But this other belief is itself in need of one more justified belief for itself to be justified and so on. Or in the cosmological argument, an event occurred because it was caused by another event that occurred before it, which was itself caused by a previous event, and so on. This principle by itself is not sufficient: it does not lead to a regress if there is no X that is F. This is why an additional triggering condition has to be fulfilled: there has to be an X that is F for the regress to get started. So the regress starts with the fact that X is F. According to the recursive principle, this is only possible if there is a distinct Y that is also F. But in order to account for the fact that Y is F, we need to posit a Z that is F and so on. Once the regress has started, there is no way of stopping it since a new entity has to be introduced at each step in order to make the previous step possible.
An infinite regress argument is an argument against a theory based on the fact that this theory leads to an infinite regress. For such an argument to be successful, it has to demonstrate not just that the theory in question entails an infinite regress but also that this regress is vicious. The mere existence of an infinite regress by itself is not a proof for anything. So in addition to connecting the theory to a recursive principle paired with a triggering condition, the argument has to show in which way the resulting regress is vicious. For example, one form of evidentialism in epistemology holds that a belief is only justified if it is based on another belief that is justified. An opponent of this theory could use an infinite regress argument by demonstrating (1) that this theory leads to an infinite regress (e.g. by pointing out the recursive principle and the triggering condition) and (2) that this infinite regress is vicious (e.g. by showing that it is implausible given the limitations of the human mind). In this example, the argument has a negative form since it only denies that another theory is true. But it can also be used in a positive form to support a theory by showing that its alternative involves a vicious regress. This is how the cosmological argument for the existence of God works: it claims that positing God's existence is necessary in order to avoid an infinite regress of causes.
Viciousness
For an infinite regress argument to be successful, it has to show that the involved regress is vicious. A non-vicious regress is called virtuous or benign. Traditionally, it was often assumed without much argument that each infinite regress is vicious but this assumption has been put into question in contemporary philosophy. In most cases, it is not self-evident whether an infinite regress is vicious or not. The truth regress constitutes an example of an infinite regress that is not vicious: if the proposition "P" is true, then the proposition that "It is true that P" is also true and so on. Infinite regresses pose a problem mostly if the regress concerns concrete objects. Abstract objects, on the other hand, are often considered to be unproblematic in this respect. For example, the truth-regress leads to an infinite number of true propositions or the Peano axioms entail the existence of infinitely many natural numbers. But these regresses are usually not held against the theories that entail them.
There are different ways how a regress can be vicious. The most serious type of viciousness involves a contradiction in the form of metaphysical impossibility. Other types occur when the infinite regress is responsible for the theory in question being implausible or for its failure to solve the problem it was formulated to solve. The vice of an infinite regress can be local if it causes problems only for certain theories when combined with other assumptions, or global otherwise. For example, an otherwise virtuous regress is locally vicious for a theory that posits a finite domain. In some cases, an infinite regress is not itself the source of the problem but merely indicates a different underlying problem.
Impossibility
Infinite regresses that involve metaphysical impossibility are the most serious cases of viciousness. The easiest way to arrive at this result is by accepting the assumption that actual infinities are impossible, thereby directly leading to a contradiction. This anti-infinitists position is opposed to infinity in general, not just specifically to infinite regresses. But it is open to defenders of the theory in question to deny this outright prohibition on actual infinities. For example, it has been argued that only certain types of infinities are problematic in this way, like infinite intensive magnitudes (e.g. infinite energy densities). But other types of infinities, like infinite cardinality (e.g. infinitely many causes) or infinite extensive magnitude (e.g. the duration of the universe's history) are unproblematic from the point of view of metaphysical impossibility. While there may be some instances of viciousness due to metaphysical impossibility, most vicious regresses are problematic because of other reasons.
Implausibility
A more common form of viciousness arises from the implausibility of the infinite regress in question. This category often applies to theories about human actions, states or capacities. This argument is weaker than the argument from impossibility since it allows that the regress in question is possible. It only denies that it is actual. For example, it seems implausible due to the limitations of the human mind that there are justified beliefs if this entails that the agent needs to have an infinite amount of them. But this is not metaphysically impossible, e.g. if it is assumed that the infinite number of beliefs are only non-occurrent or dispositional while the limitation only applies to the number of beliefs one is actually thinking about at one moment. Another reason for the implausibility of theories involving an infinite regress is due to the principle known as Ockham's razor, which posits that we should avoid ontological extravagance by not multiplying entities without necessity. Considerations of parsimony are complicated by the distinction between quantitative and qualitative parsimony: concerning how many entities are posited in contrast to how many kinds of entities are posited. For example, the cosmological argument for the existence of God promises to increase quantitative parsimony by positing that there is one first cause instead of allowing an infinite chain of events. But it does so by decreasing qualitative parsimony: it posits God as a new type of entity.
Failure to explain
Another form of viciousness applies not to the infinite regress by itself but to it in relation to the explanatory goals of a theory. Theories are often formulated with the goal of solving a specific problem, e.g. of answering the question why a certain type of entity exists. One way how such an attempt can fail is if the answer to the question already assumes in disguised form what it was supposed to explain. This is akin to the informal fallacy of begging the question. From the perspective of a mythological world view, for example, one way to explain why the earth seems to be at rest instead of falling down is to hold that it rests on the back of a giant turtle. In order to explain why the turtle itself is not in free fall, another even bigger turtle is posited and so on, resulting in a world that is turtles all the way down. Despite its shortcomings in clashing with modern physics and due to its ontological extravagance, this theory seems to be metaphysically possible assuming that space is infinite. One way to assess the viciousness of this regress is to distinguish between local and global explanations. A local explanation is only interested in explaining why one thing has a certain property through reference to another thing without trying to explain this other thing as well. A global explanation, on the other hand, tries to explain why there are any things with this property at all. So as a local explanation, the regress in the turtle theory is benign: it succeeds in explaining why the earth is not falling. But as a global explanation, it fails because it has to assume rather than explain at each step that there is another thing that is not falling. It does not explain why nothing at all is falling.
It has been argued that infinite regresses can be benign under certain circumstances despite aiming at global explanation. This line of thought rests on the idea of the transmission involved in the vicious cases: it is explained that X is F because Y is F where this F was somehow transmitted from Y to X. The problem is that to transfer something, it first must be possessed, so the possession is presumed rather than explained. For example, in trying to explain why one's neighbor has the property of being the owner of a bag of sugar, it is revealed that this bag was first in someone else's possession before it was transferred to the neighbor and that the same is true for this and every other previous owner. This explanation is unsatisfying since ownership is presupposed at every step. In non-transmissive explanations, however, Y is still the reason for X being F and Y is also F but this is just seen as a contingent fact. This line of thought has been used to argue that the epistemic regress is not vicious. From a Bayesian point of view, for example, justification or evidence can be defined in terms of one belief raising the probability that another belief is true. The former belief may also be justified but this is not relevant for explaining why the latter belief is justified.
Responses to infinite regress arguments
Philosophers have responded to infinite regress arguments in various ways. The criticized theory can be defended, for example, by denying that an infinite regress is involved. Infinitists, on the other hand, embrace the regress but deny that it is vicious. Another response is to modify the theory in order to avoid the regress. This can be achieved in the form of foundationalism or of coherentism.
Foundationalism
Traditionally, the most common response is foundationalism. It posits that there is a first element in the series from which all the other elements arise but which is not itself explained this way. So from any given position, the series can be traced back to elements on the most fundamental level, which the recursive principle fails to explain. This way an infinite regress is avoided. This position is well-known from its applications in the field of epistemology. Foundationalist theories of epistemic justification state that besides inferentially justified beliefs, which depend for their justification on other beliefs, there are also non-inferentially justified beliefs. The non-inferentially justified beliefs constitute the foundation on which the superstructure consisting of all the inferentially justified beliefs rests. Acquaintance theories, for example, explain the justification of non-inferential beliefs through acquaintance with the objects of the belief. On such a view, an agent is inferentially justified to believe that it will rain tomorrow based on the belief that the weather forecast told so. They are non-inferentially justified in believing that they are in pain because they are directly acquainted with the pain. So a different type of explanation (acquaintance) is used for the foundational elements.
Another example comes from the field of metaphysics concerning the problem of ontological hierarchy. One position in this debate claims that some entities exist on a more fundamental level than other entities and that the latter entities depend on or are grounded in the former entities. Metaphysical foundationalism is the thesis that these dependence relations do not form an infinite regress: that there is a most fundamental level that grounds the existence of the entities from all other levels. This is sometimes expressed by stating that the grounding-relation responsible for this hierarchy is well-founded.
Coherentism
Coherentism, mostly found in the field of epistemology, is another way to avoid infinite regresses. It is based on a holistic explanation that usually sees the entities in question not as a linear series but as an interconnected network. For example, coherentist theories of epistemic justification hold that beliefs are justified because of the way they hang together: they cohere well with each other. This view can be expressed by stating that justification is primarily a property of the system of beliefs as a whole. The justification of a single belief is derivative in the sense that it depends on the fact that this belief belongs to a coherent whole. Laurence BonJour is a well-known contemporary defender of this position.
Examples
Aristotle
Aristotle argued that knowing does not necessitate an infinite regress because some knowledge does not depend on demonstration:
Philosophy of mind
Gilbert Ryle argues in the philosophy of mind that mind-body dualism is implausible because it produces an infinite regress of "inner observers" when trying to explain how mental states are able to influence physical states.
See also
Antecedent-contained deletion
Bradley's regress
Chicken or the egg
Cosmological argument
Droste effect
First cause
Fractal
Gunk (mereology)
Homunculus argument
Münchhausen trilemma
Recursion
Third man argument
What the Tortoise Said to Achilles
Zeno's paradoxes
References
External links
Philosophical arguments
Philosophical logic
Recursion | Infinite regress | [
"Mathematics"
] | 3,234 | [
"Mathematical logic",
"Recursion"
] |
3,004,912 | https://en.wikipedia.org/wiki/Craigellachie%20Bridge | Craigellachie Bridge is a cast iron arch bridge across the River Spey at Craigellachie, near to the village of Aberlour in Moray, Scotland. It was designed by the renowned civil engineer Thomas Telford and built from 1812 to 1814. It is a Category A listed structure.
Construction
The bridge has a single span of approximately and was revolutionary for its time, in that it used an extremely slender arch which was not possible using traditional masonry construction. The ironwork was cast at the Plas Kynaston iron foundry at Cefn Mawr, near Ruabon in Denbighshire by William Hazledine, who cast a number of Telford bridges. The ironwork was transported from the foundry through the Ellesmere Canal and Pontcysyllte Aqueduct then by sea to Speymouth, where it was loaded onto wagons and taken to the site. Testing in the 1960s revealed that the cast-iron had an unusually high tensile strength. This was probably specified by Telford because, unlike in traditional masonry arch bridges, some sections of the arch are not in compression under loading.
At each end of the structure there are two high masonry mock-medieval towers, featuring arrow slits and miniature crenellated battlements.
History
The bridge was in regular use until 1963, when it was closed for a major refurbishment. A plaque records the completion of this work in 1964.
The side railings and spandrel members were replaced with new ironwork fabricated to match the originals. A 14 ton restriction was placed on the bridge at this point. This, along with the fact that the road to the north of the bridge takes a sharp right-angled turn to avoid a rock face, made it unsuitable for modern vehicles. Despite this, it carried foot and vehicle traffic across the River Spey until 1972, when its function was replaced by a reinforced concrete beam bridge built by Sir William Arrol & Co. which opened in 1970 and carries the A941 road today. Telford's bridge remains in good condition, and is still open to pedestrians and cyclists. The bridge has been given Category A listed status by Historic Scotland and has been designated a civil engineering landmark by the Institution of Civil Engineers and American Society of Civil Engineers.
In 1994, it hosted a parade upon the amalgamation of The Gordon Highlanders and The Queen's Own Highlanders (Seaforth and Camerons) to form The Highlanders (Seaforth, Gordons and Camerons). A plaque has been fitted to the bridge parapet to commemorate this.
Moray Council maintain the bridge, but it is not known who owns it. In November 2017 efforts were started to discover the owner.
Usage in media
Scottish composer William Marshall saw the bridge completed in 1814, and included a strathspey named for it, Craigellachie Brig, in his 1822 collection of tunes.
The bridge was commemorated on a Royal Mail postage stamp in 2015.
It also features in the artwork and logos of Spey Valley Brewery who brew an 1814 lager in commemoration of the bridge.
References
Bibliography
External links
Detail on the bridge - Scottish Historical Register
Musical notation for the Craigellachie Bridge Strathspey Reel
Deck arch bridges
Bridges completed in 1814
Category A listed buildings in Moray
Listed bridges in Scotland
Scheduled monuments in Scotland
Bridges by Thomas Telford
Road bridges in Scotland
Historic Civil Engineering Landmarks
Cast-iron arch bridges in Scotland
River Spey
1814 establishments in Scotland
Aberlour | Craigellachie Bridge | [
"Engineering"
] | 695 | [
"Civil engineering",
"Historic Civil Engineering Landmarks"
] |
3,005,092 | https://en.wikipedia.org/wiki/Ribosome%20shunting | Ribosome shunting is a mechanism of translation initiation in which ribosomes bypass, or "shunt over", parts of the 5' untranslated region to reach the start codon. However, a benefit of ribosomal shunting is that it can translate backwards allowing more information to be stored than usual in an mRNA molecule. Some viral RNAs have been shown to use ribosome shunting as a more efficient form of translation during certain stages of viral life cycle or when translation initiation factors are scarce (e.g. cleavage by viral proteases). Some viruses known to use this mechanism include adenovirus, Sendai virus, human papillomavirus, duck hepatitis B pararetrovirus, rice tungro bacilliform viruses, and cauliflower mosaic virus. In these viruses the ribosome is directly translocated from the upstream initiation complex to the start codon (AUG) without the need to unwind RNA secondary structures.
Ribosome shunting in Cauliflower mosaic virus
Translation of Cauliflower mosaic virus (CaMV) 35S RNA is initiated by a ribosome shunt. The 35S RNA of CaMV contains a ~600 nucleotide leader sequence which contains 7-9 short open reading frames (sORFs) depending on the strain. This long leader sequence has the potential to form an extensive complex stem-loop structure, which is an inhibitory element for expression of following ORFs. However, translation of ORFs downstream of the CaMV 35S RNA leader has been commonly observed. Ribosome shunting model indicates with the collaboration of initiation factors, ribosomes start scanning from capped 5’-end and scans for a short distance until it hits the first sORF. The hairpin structure formed by leader brings the first long ORF into the close spatial vicinity of a 5’-proximal sORF. After read through sORF A, the 80S scanning ribosome disassembles at the stop codon, which is the shunt take-off site. The 40S ribosomal subunits keep combining with RNA, and bypass the strong stem-loop structural element, land at the shunt acceptor site, resume scanning and reinitiate at the first long ORF. 5’-proximal sORF A and the stem-loop structure itself are two essential elements for CaMV shunting [5]. sORFs with 2-15 codons, and 5-10 nucleotides between sORF stop codon and the base of the stem structure are optimal for ribosome shunting, while the minimal (start-stop) ORF does not promote shunting.
Ribosome shunting in Rice tungro bacilliform pararetrovirus
Ribosome shunting process was first discovered in CaMV in 1993, and then was reported in Rice tungro bacilliform virus (RTBV) in 1996. The mechanism of ribosome shunting in RTBV resembles that in CaMV: it also requires the first short ORF as well as a following strong secondary structure. Swapping of the conserved shunt elements between CaMV and RTBV revealed the importance of nucleotide composition of the landing sequence for efficient shunting, indicating that the mechanism of ribosome shunting is evolutionary conserved in plant pararetroviruses.
Ribosome shunting in Sendai virus
Sendai virus Y proteins are initiated by ribosome shunting. Among 8 primary translation products of Sendai virus P/C mRNA, leaky scanning accounts for translation of protein C’, P, and C proteins, while expression of protein Y1 and Y2 is initiated via a ribosomal shunt discontinuous scanning. Scanning complex enters 5’ cap and scan ~50 nucleotides of 5’ UTR, and then is transferred to an acceptor site at or close the Y initiation codons. In the case of Sendai virus, no specific donor site sequences are required.
Ribosome shunt in Adenovirus
Ribosome shunting is observed during expression of late adenovirus mRNAs. Late adenovirus mRNAs contains a 5’ tripartite leader, a highly conserved 200-nucleotide NTR with a 25- to 44- nucleotide unstructured 5’ conformation followed by a complex group of stable hairpin structure, which confers preferential translation by reducing the requirement for the eIF-4F (cap-binding protein complex), which is inactivated by adenovirus to interfere with cellular protein translation. When eIF4E is abundant, the subunit binds to the 5' cap on mRNAs, forming an eIF4 complex leading to shunting; however, when eIF4E is altered or deactivated during late adenovirus infection of heat shock, the tripartite leader exclusively and efficiently directs initiation by shunting.
While Adenovirus required tyrosine kinase to infect the cells without it by disrupting the cap-initiation complex known as the tripartite leader. It disrupts the process via ribosome shunting, in tyrosine phosphorylation. There are two key sites for the binding of the ribosome. In translating viral mRNA and suppressing the translation while being capped by ribosome shunting process.
In the case of adenovirus late mRNA and hsp70 mRNA, instead of recognition of stop codon of first short ORF, pausing of translation is caused by scanning ribosome with three conserved sequences that are complementary to the 3’ hairpin of 18S ribosomal RNA. The mechanism for ribosome shunt involves the larger subunit binding upstream of the start codon. The polymerase is then able to leapfrog using protein binding and a power stroke to bypass the start codon on the coding mRNA. The tripate is then inserted into the parent strand to create a new binding site for further replication.
References
Protein biosynthesis | Ribosome shunting | [
"Chemistry"
] | 1,231 | [
"Protein biosynthesis",
"Gene expression",
"Biosynthesis"
] |
3,005,139 | https://en.wikipedia.org/wiki/Cauchy%27s%20equation | In optics, Cauchy's transmission equation is an empirical relationship between the refractive index and wavelength of light for a particular transparent material. It is named for the mathematician Augustin-Louis Cauchy, who originally defined it in 1830 in his article "The refraction and reflection of light".
The equation
The most general form of Cauchy's equation is
where n is the refractive index, λ is the wavelength, A, B, C, etc., are coefficients that can be determined for a material by fitting the equation to measured refractive indices at known wavelengths. The coefficients are usually quoted for λ as the vacuum wavelength in micrometres.
Usually, it is sufficient to use a two-term form of the equation:
where the coefficients A and B are determined specifically for this form of the equation.
A table of coefficients for common optical materials is shown below:
The theory of light-matter interaction on which Cauchy based this equation was later found to be incorrect. In particular, the equation is only valid for regions of normal dispersion in the visible wavelength region. In the infrared, the equation becomes inaccurate, and it cannot represent regions of anomalous dispersion. Despite this, its mathematical simplicity makes it useful in some applications.
The Sellmeier equation is a later development of Cauchy's work that handles anomalously dispersive regions, and more accurately models a material's refractive index across the ultraviolet, visible, and infrared spectrum.
Humidity dependence for air
Cauchy's two-term equation for air, expanded by Lorentz to account for humidity, is as follows:
where p is the air pressure in millibar, T is the temperature in kelvin, and v is the vapor pressure of water in millibar.
See also
Sellmeier equation
References
F.A. Jenkins and H.E. White, Fundamentals of Optics, 4th ed., McGraw-Hill, Inc. (1981).
Augustin-Louis Cauchy
Optics
Electric and magnetic fields in matter
Eponymous equations of physics | Cauchy's equation | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 422 | [
"Applied and interdisciplinary physics",
"Equations of physics",
"Optics",
"Eponymous equations of physics",
"Electric and magnetic fields in matter",
"Materials science",
"Condensed matter physics",
" molecular",
"Atomic",
" and optical physics"
] |
3,005,170 | https://en.wikipedia.org/wiki/Bell%27s%20law%20of%20computer%20classes | Bell's law of computer classes formulated by Gordon Bell in 1972 describes how types of computing systems (referred to as computer classes) form, evolve and may eventually die out. New classes of computers create new applications resulting in new markets and new industries.
Description
Bell considers the law to be partially a corollary to Moore's law which states "the number of transistors per chip double every 18 months". Unlike Moore's law, a new computer class is usually based on lower cost components that have fewer transistors or less bits on a magnetic surface, etc. A new class forms about every decade. It also takes up to a decade to understand how the class formed, evolved, and is likely to continue. Once formed, a lower priced class may evolve in performance to take over and disrupt an existing class. This evolution has caused clusters of scalable personal computers with 1 to thousands of computers to span a price and performance range of use from a PC, through mainframes, to become the largest supercomputers of the day. Scalable clusters became a universal class beginning in the mid-1990s; by 2010, clusters of at least one million independent computers will constitute the world's largest cluster.
Definition: Roughly every decade a new, lower priced computer class forms based on a new programming platform, network, and interface resulting in new usage and the establishment of a new industry.
Established market class computers aka platforms are introduced and continue to evolve at roughly a constant price (subject to learning curve cost reduction) with increasing functionality (or performance) based on Moore's law that gives more transistors per chip, more bits per unit area, or increased functionality per system. Roughly every decade, technology advances in semiconductors, storage, networks, and interfaces enable the emergence of a new, lower-cost computer class (aka "platform") to serve a new need that is enabled by smaller devices (e.g. more transistors per chip, less expensive storage, displays, i/o, network, and unique interface to people or some other information processing sink or source). Each new lower-priced class is then established and maintained as a quasi-independent industry and market. Such a class is likely to evolve to substitute for an existing class or classes as described above with computer clusters.
Computer classes that conform to the law
mainframes (1960s)
minicomputers (1970s)
personal computers and workstations evolving into a network enabled by Local Area Networking or Ethernet (1980s)
web browser client-server structures enabled by the Internet (1990s)
cloud computing, e.g., Amazon Web Services (2006) or Microsoft Azure (2012)
hand held devices from media players and cell phones to tablets, e.g., Creative, iPods, BlackBerrys, iPhones, smartphones, Kindles, iPads (c. 2000–2010)
wireless sensor networks (WSNs) that enable sensor and actuator interconnection, enabling the evolving Internet of things (c. >2005)
Beginning in the 1990s, a single class of scalable computers or mega-servers, (built from clusters of a few to tens of thousands of commodity microcomputer-storage-networked bricks), began to cover and replace mainframes, minis, and workstations to become the largest computers of the day, and when applied for scientific calculation they are commonly called a supercomputer.
History
Bell's law of computer classes and class formation was first mentioned in 1970 with the introduction of the Digital Equipment PDP-11 mini to differentiate it from mainframes and the potentially emerging micros. The law was described in 1972 by Gordon Bell. The emergence and observation of a new, lower-priced microcomputer class based on the microprocessor stimulated the creation of the law that Bell described in articles and Bell's books.
Other computer industry laws
See also the several laws (e.g. Moore's law, Metcalfe's law) that describe the computer industry.
References
Adages
Bell's Law of Computer Classes
Computer architecture statements | Bell's law of computer classes | [
"Technology"
] | 838 | [
"Classes of computers",
"Computers",
"Computer systems"
] |
3,005,200 | https://en.wikipedia.org/wiki/Pharmaceutical%20code | Pharmaceutical codes are used in medical classification to uniquely identify medication. They may uniquely identify an active ingredient, drug system (including inactive ingredients and time-release agents) in general, or a specific pharmaceutical product from a specific manufacturer.
Examples
Drug system identifiers (manufacturer-specific including inactive ingredients):
National Drug Code (NDC) — administered by Food and Drug Administration.
Drug Identification Number (DIN) — administered by Health Canada under the Food and Drugs Act
Hong Kong Drug Registration — administered by the Pharmaceutical Service of the Department of Health (Hong Kong)
National Pharmaceutical Product Index - South Africa
Hierarchical systems:
Anatomical Therapeutic Chemical Classification System (AT, or ATC/DDD) — administered by World Health Organization
Generic Product Identifier (GPI) — hierarchical classification number published by MediSpan
SNOMED — C axis
Ingredients:
Unique Ingredient Identifier
Proprietary database identifiers include those assigned by First Databank, Micromedex, MediSpan, Gold Standard Drug Database (published by Elsevier), and Cerner Multum MediSource Lexicon; these are cross-indexed by RxNorm, which also assigns a unique identifier (RxCUI) to every combination of active ingredient and dose level.
See also
Drug nomenclature
Drug class
References
Pharmacological classification systems | Pharmaceutical code | [
"Chemistry"
] | 268 | [
"Pharmacological classification systems",
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
3,005,202 | https://en.wikipedia.org/wiki/Atomic%20model%20%28mathematical%20logic%29 | In model theory, a subfield of mathematical logic, an atomic model is a model such that the complete type of every tuple is axiomatized by a single formula. Such types are called principal types, and the formulas that axiomatize them are called complete formulas.
Definitions
Let T be a theory. A complete type p(x1, ..., xn) is called principal or atomic (relative to T) if it is axiomatized relative to T by a single formula φ(x1, ..., xn) ∈ p(x1, ..., xn).
A formula φ is called complete in T if for every formula ψ(x1, ..., xn), the theory T ∪ {φ} entails exactly one of ψ and ¬ψ.
It follows that a complete type is principal if and only if it contains a complete formula.
A model M is called atomic if every n-tuple of elements of M satisfies a formula that is complete in Th(M)—the theory of M.
Examples
The ordered field of real algebraic numbers is the unique atomic model of the theory of real closed fields.
Any finite model is atomic.
A dense linear ordering without endpoints is atomic.
Any prime model of a countable theory is atomic by the omitting types theorem.
Any countable atomic model is prime, but there are plenty of atomic models that are not prime, such as an uncountable dense linear order without endpoints.
The theory of a countable number of independent unary relations is complete but has no completable formulas and no atomic models.
Properties
The back-and-forth method can be used to show that any two countable atomic models of a theory that are elementarily equivalent are isomorphic.
Notes
References
Model theory | Atomic model (mathematical logic) | [
"Mathematics"
] | 378 | [
"Mathematical logic",
"Model theory"
] |
3,005,228 | https://en.wikipedia.org/wiki/Nuclear%20Explosions%20for%20the%20National%20Economy | Nuclear Explosions for the National Economy (; sometimes referred to as Program #7) was a Soviet program to investigate peaceful nuclear explosions (PNEs). It was analogous to the United States program Operation Plowshare, although the Soviet one consists of 124 tests.
One of the better-known tests was Chagan of January 15, 1965. Radioactivity from the Chagan test was detected over Japan by both the U.S. and Japan in apparent violation of the 1963 Partial Test Ban Treaty (PTBT). The United States complained to the Soviets, but the matter was dropped.
History
In November 1949, shortly after the test of their first nuclear device on September 23, 1949, Andrey Vyshinsky, the Soviet representative to the United Nations, delivered a statement justifying their efforts to develop their own nuclear weapons capability. He said:
However the USSR did not immediately follow the U.S. lead in 1958 in establishing a program. Presumably, their position in support of a comprehensive nuclear testing ban stalled any efforts to establish such a program until the mid-1960s.
When Nuclear Explosions for the National Economy was finally formally established, Alexander D. Zakharenkov, a chief weapons designer, was appointed head of the program. Initially, the Soviet program was focused on two applications, nuclear excavation and petroleum stimulation, similar to the U.S. program. However, interest in other applications quickly developed, and within five years the Soviet program was actively exploring six or seven applications involving participation by some ten government departments.
Once underway the Soviets conducted a much more vigorous program than the Americans' Operation Plowshare, consisting of some 156 nuclear tests, some with multiple devices, between 1965 and 1989. These tests were similar in aims to the American effort, with the exception that six of the shots were considered of an applied nature, that is they were not tests as such, but were used to put out runaway gas well fires and a methane blow out.
There were in fact two programs:
"Employment of Nuclear Explosive Technologies in the Interests of National Economy", also referred to as "Program 6", involved industrial underground PNEs and testing of new PNE technologies. As part of the program, 124 tests with 135 devices were conducted. Primary objectives of the program were water reservoir development, dam and canal construction, and creation of underground cavities for toxic waste storage.
"Peaceful Nuclear Explosions for the National Economy", also referred to as "Program 7", involved testing of industrial nuclear charges for use in peaceful activities. Nuclear detonations were conducted with the stated purpose of searching for useful mineral resources with reflection seismology, breaking up ore bodies, stimulating the production of oil and gas, and forming underground cavities for storing the recovered oil and gas. The "Program" numbers come from the USSR's classification system of nuclear explosions, the first five programs designating various phases of nuclear weapon development.
All together, the Program 7 conducted 115 nuclear explosions. Among them:
39 explosions for geological exploration (trying to find new natural gas deposits by studying seismic waves produced by small nuclear explosions)
25 explosions to intensify oil and gas debits
22 explosions to create underground storage for natural gas
5 explosions to extinguish large natural gas fountains that were burning
4 explosions to create channels and dams (including the Chagan test in Kazakhstan, and the Taiga test on the potential route of the Pechora–Kama Canal)
2 explosions to crush ore in open-pit mines
2 explosions to create underground storage for toxic wastes
1 explosion to facilitate coal mining in an underground mine
19 explosions for research purposes (studying possible migration of the radioactivity from the place of the explosions).
These explosions were financed by various ministries: 51 explosions were financed by the Ministry for Geology, 26 explosions were financed by the Ministry for Natural Gas, 13 explosions were financed by the Ministry for Oil, 19 explosions were financed by the MinSredMash itself (the predecessor of the Federal Atomic Energy Agency). There were two large explosions of 140 kilotons and 105 kilotons; all others were relatively small with an average yield of 12.5 kilotons. For example, one 30-kiloton explosion was used to close the Uzbekistan Urtabulak gas well in 1966 that had been blowing since 1963, and on May 11th 1968 a 47-kiloton explosive was used to seal a higher pressure blowout at the nearby Pamuk gas field, Gas fire blowouts like this occurred three more times over the following years, On July 9th 1972 a 3.8-Kiloton explosive was used in Krestishche gas field in Ukraine, And again in the same gas field on August 6th 1972 where a 5-Kiloton explosive was used (a separate well from the July operation), And another was used at the Kumzhinskoye gas field in Northern Russia, Where the fire at this site had been burning for more than a year before being extinguished by a 37.5 Kiloton explosive on December 18th 1981, These successful experiments were later cited as possible precedents for stopping the Deepwater Horizon oil spill.
The last nuclear explosion by the Program 7, codenamed Rubin-1, was performed in Arkhangelsk Oblast on September 6, 1988. The explosion was a part of a seismic program for geological exploration. The Soviets agreed to stop their PNE program at the end of 1988 as a result of then-president Mikhail Gorbachev's disarmament initiative.
There are proponents for continuing the PNE programs in modern Russia. They (e.g. A. Koldobsky) state that the program has already paid for itself and saved the USSR billions of rubles and can save even more if it would continue. They also allege that the PNE is the only feasible way to put out large fountains and fires on natural gas deposits, and it is the safest and most economically viable way to destroy chemical weapons.
Their opponents, including Alexey Yablokov, state that all PNE technologies have non-nuclear alternatives and that many PNEs actually caused nuclear disasters.
Problems
Among the catastrophes was the Kraton-3 explosion in Vilyuy, Yakutia, in 1978, that was supposed to unearth diamond-rich ores. Instead, the amount of diamonds was insignificant but the plutonium pollution of water was much higher than predicted. According to the anti-nuclear activist Alexei Yablokov, the level of plutonium in the drinking water of Vilyuy region 20 years after the explosion is ten thousand times higher than the maximal sanitary norm.
Another catastrophe resulted from the Globus-1 explosion near the village of Galkino at , 40 kilometers from Kineshma city on September 19, 1971. It was a small underground explosion of 2.5 kilotons that was a part of the seismological program for oil and gas exploration. Unexpectedly a large amount of radioactive gases escaped through cracks in the ground, creating a significant radioactive hot spot two kilometers in diameter, in the relatively densely populated area of European Russia. A small tributary of the Volga, the Shacha, changed its location and threatened to flood the explosion site. This could have led to nuclear pollution of the entire Volga region. Some engineers suggested building a sarcophagus (similar to the Chernobyl's "Object Shelter") covering the site, and excavating a 12 km channel to shift the Shacha river away from the place of the explosion, but the plans appeared prohibitively expensive.
The experiments ended with the adoption of a unilateral moratorium on nuclear weapons testing at Soviet sites in 1989. Although this primarily was designed to support Mikhail Gorbachev's call for a worldwide ban on nuclear weapons tests, the Russians apparently applied the moratorium to peaceful nuclear explosions as well.
Implications
The Soviet PNE program was many times larger than the U.S. Plowshare program in terms of both the number of applications explored with field experiments and the extent to which they were introduced into industrial use. Several PNE applications, such as deep seismic sounding and oil stimulation, were explored in depth and appeared to have had a positive cost benefit at minimal public risk. Several others, such as storage, developed significant technical problems that cast a shadow on their general applicability. Some, such as closure of runaway gas wells, demonstrated a unique technology that may yet find application as a last resort. Still others were the subject of one or two tests but were not explored further for reasons that have never been explained. Overall, the program represented a significant technical effort to explore what was seen at the time to be a promising new technology, and it generated a large body of data, although only a small fraction of it has been made public.
See also
Peaceful nuclear explosions
Soviet atomic bomb project
1971 Soviet nuclear tests
Категория:Мирные ядерные взрывы на территории СССР (Articles on individual explosions in Russian Wikipedia)
Notes
References
External links
USSR Nuclear Weapons Tests and Peaceful Nuclear Explosions. 1949 through 1990, an official publication of Federal Atomic Energy Agency.
1966 Urta-Bulak well #11 blowout
Cold War history of the Soviet Union
Economy of the Soviet Union
Peaceful nuclear explosions | Nuclear Explosions for the National Economy | [
"Chemistry"
] | 1,903 | [
"Explosions",
"Peaceful nuclear explosions"
] |
3,005,304 | https://en.wikipedia.org/wiki/Insulin%20analog | An insulin analog (also called an insulin analogue) is any of several types of medical insulin that are altered forms of the hormone insulin, different from any occurring in nature, but still available to the human body for performing the same action as human insulin in terms of controlling blood glucose levels in diabetes. Through genetic engineering of the underlying DNA, the amino acid sequence of insulin can be changed to alter its ADME (absorption, distribution, metabolism, and excretion) characteristics. Officially, the U.S. Food and Drug Administration (FDA) refers to these agents as insulin receptor ligands (because, like insulin itself, they are ligands of the insulin receptor), although they are usually just referred to as insulin analogs or even (loosely but commonly) just insulin (without further specification).
These modifications have been used to create two types of insulin analogs: those that are more readily absorbed from the injection site and therefore act faster than natural insulin injected subcutaneously, intended to supply the bolus level of insulin needed at mealtime (prandial insulin); and those that are released slowly over a period of between 8 and 24 hours, intended to supply the basal level of insulin during the day and particularly at nighttime (basal insulin). The first insulin analog (insulin Lispro rDNA) was approved for human therapy in 1996 and was manufactured by Eli Lilly and Company.
Fast acting
Lispro
Eli Lilly and Company developed and marketed the first rapid-acting insulin analogue (insulin lispro rDNA) Humalog. It was engineered through recombinant DNA technology so that the penultimate lysine and proline residues on the C-terminal end of the B-chain were reversed. This modification did not alter the insulin receptor binding, but blocked the formation of insulin dimers and hexamers. This allowed larger amounts of active monomeric insulin to be available for postprandial (after meal) injections.
Aspart
Novo Nordisk created "aspart" and marketed it as NovoLog/NovoRapid (UK-CAN) as a rapid-acting insulin analogue. It was created through recombinant DNA technology so that the amino acid, B28, which is normally proline, is substituted with an aspartic acid residue. The sequence was inserted into the yeast genome, and the yeast expressed the insulin analogue, which was then harvested from a bioreactor. This analogue prevents the formation of hexamers, to create a faster acting insulin. It is approved for use in CSII pumps and Flexpen, Novopen delivery devices for subcutaneous injection.
Glulisine
Glulisine is rapid acting insulin analog from Sanofi-Aventis, approved for use with a regular syringe, in an insulin pump. Standard syringe delivery is also an option. It is sold under the name Apidra. The FDA-approved label states that it differs from regular human insulin by its rapid onset and shorter duration of action. The differences are: replacement of B3 asparagine with lysine, replacement of B29 lysine with glutamic acid.
Long acting
Detemir insulin
Novo Nordisk created insulin detemir and markets it under the trade name Levemir as a long-lasting insulin analogue for maintaining the basal level of insulin. The basal level of insulin may be maintained for up to 20 hours, but the time is affected by the size of the injected dose.
The changes are: removal of B30 threonine, attachment of a myristic acid tail to the B29 lysine's "tail" nitrogen. As a result, this insulin binds to serum albumin with high affinity, increasing its duration of action.
Degludec insulin
This is an ultralong-acting insulin analogue developed by Novo Nordisk, which markets it under the brand name Tresiba. It is administered once daily and has a duration of action that lasts up to 40 hours (compared to 18 to 26 hours provided by other marketed long-acting insulins such as insulin glargine and insulin detemir). The change involves attachment of a hexadecanedioic acid tail to the B29 lysine's "tail" nitrogen. This allows the molecule to form multi-hexamers that last longer.
Glargine insulin
Sanofi-Aventis developed glargine as a longer-lasting insulin analogue, and sells it under the brand name Lantus. It was created by modifying three amino acids. Two positively charged arginine molecules were added to the C-terminus of the B-chain, and they shift the isoelectric point from 5.4 to 6.7, making glargine more soluble at a slightly acidic pH and less soluble at a physiological pH. Replacing the acid-sensitive asparagine at position 21 in the A-chain (A21) by glycine is needed to avoid deamination and dimerization of the arginine residue. These three structural changes and formulation with zinc result in a prolonged action when compared with biosynthetic human insulin. When the pH 4.0 solution is injected, most of the material precipitates and is not bioavailable. A small amount is immediately available for use, and the remainder is sequestered in subcutaneous tissue. As the glargine is used, small amounts of the precipitated material will move into solution in the bloodstream, and the basal level of insulin will be maintained up to 24 hours. The onset of action of subcutaneous insulin glargine is somewhat slower than NPH human insulin. It is clear solution as there is no zinc in formula. The biosimilar insulin glargine-yfgn (Semglee) was approved for medical use in the United States in July 2021, and in the European Union in March 2018.
Comparison with other insulins
NPH
NPH (Neutral Protamine Hagedorn) insulin is an intermediate-acting insulin with delayed absorption after subcutaneous injection, used for basal insulin support in diabetes type 1 and type 2. NPH insulins are suspensions that require shaking for reconstitution prior to injection. Many people reported problems when being switched to intermediate acting insulins in the 1980s, using NPH formulations of porcine/bovine insulins. Basal (long-acting) insulin analogs were subsequently developed and introduced into clinical practice to achieve more predictable absorption profiles and clinical efficacy.
As its name suggests, it contains both insulin and protamine and has a neutral pH. It also contains zinc and phenol.
Animal insulin
The amino acid sequence of animal insulins in different mammals may be similar to human insulin (insulin human INN), there is however considerable viability within vertebrate species. Porcine insulin has only a single amino acid variation from the human variety, and bovine insulin varies by three amino acids. Both are active on the human receptor with approximately the same strength. Bovine insulin and porcine insulin may be considered as the first clinically used insulin analogs (naturally occurring, produced by extraction from animal pancreas), at the time when biosynthetic human insulin (insulin human rDNA) was not available. There are extensive reviews on structure-relationship of naturally occurring insulins (phylogenic relationship in animals) and structural modifications. Prior to the introduction of biosynthetic human insulin, insulin derived from sharks was widely used in Japan. Insulin from some species of fish may be also effective in humans. Non-human insulins have caused allergic reactions in some patients related to the extent of purification, formation of non-neutralising antibodies is rarely observed with recombinant human insulin (insulin human rDNA) but allergy may occur in some patients. This may be enhanced by the preservatives used in insulin preparations, or occur as a reaction to the preservative. Biosynthetic insulin (insulin human rDNA) has largely replaced animal insulin.
Modifications
Before biosynthetic human recombinant analogues were available, porcine insulin was chemically converted into human insulin. Chemical modifications of the amino acid side chains at the N-terminus and/or the C-terminus were made in order to alter the ADME characteristics of the analogue. Semisynthetic insulins were clinically used for some time based on chemical modification of animal insulins, for example Novo Nordisk enzymatically converted porcine insulin into semisynthetic 'human' insulin by removing the single amino acid that varies from the human variety, and chemically adding the human amino acid.
Normal unmodified insulin is soluble at physiological pH. Analogues have been created that have a shifted isoelectric point so that they exist in a solubility equilibrium in which most precipitates out but slowly dissolves in the bloodstream and is eventually excreted by the kidneys. These insulin analogues are used to replace the basal level of insulin, and may be effective over a period of up to 24 hours. However, some insulin analogues, such as insulin detemir, bind to albumin rather than fat like earlier insulin varieties, and results from long-term usage (e.g. more than 10 years) are currently not available but required for assessment of clinical benefit.
Unmodified human and porcine insulins tend to complex with zinc in the blood, forming hexamers. Insulin in the form of a hexamer will not bind to its receptors, so the hexamer has to slowly equilibrate back into its monomers to be biologically useful. Hexameric insulin delivered subcutaneously is not readily available for the body when insulin is needed in larger doses, such as after a meal (although this is more a function of subcutaneously administered insulin, as intravenously dosed insulin is distributed rapidly to the cell receptors, and therefore, avoids this problem). Zinc combinations of insulin are used for slow release of basal insulin. Basal insulin support is required throughout the day representing about 50% of daily insulin requirement, the insulin amount needed at mealtime makes up for the remaining 50%. Non hexameric insulins (monomeric insulins) were developed to be faster acting and to replace the injection of normal unmodified insulin before a meal. There are phylogenetic examples for such monomeric insulins in animals.
Carcinogenicity
All insulin analogs must be tested for carcinogenicity, as insulin engages in cross-talk with IGF pathways, which can cause abnormal cell growth and tumorigenesis. Modifications to insulin always carry the risk of unintentionally enhancing IGF signalling in addition to the desired pharmacological properties. There has been concern with the mitogenic activity and the potential for carcinogenicity of glargine. Several epidemiological studies have been performed to address these issues. Recent study result of the 6.5 years Origin study with glargine have been published.
Research on safety, efficacy, and comparative effectiveness
A meta-analysis completed in 2007 and updated in 2020 of numerous randomized controlled trials by the international Cochrane Collaboration found that the effects on blood glucose and glycated haemoglobin A1c (HbA1c) were comparable, treatment with glargine and detemir resulted in fewer cases of hypoglycemia when compared to NPH insulin. Treatment with detrimir also reduced the frequency of serious hypoglycemia. This review did note limitations, such as low glucose and HbA1c targets, that could limit the applicability of these findings to daily clinical practice.
In 2007, Germany's Institute for Quality and Cost Effectiveness in the Health Care Sector (IQWiG) report, concluded that there is currently "no evidence" available of the superiority of rapid-acting insulin analogs over synthetic human insulins in the treatment of adult patients with type 1 diabetes. Many of the studies reviewed by IQWiG were either too small to be considered statistically reliable and, perhaps most significantly, none of the studies included in their widespread review were blinded, the gold-standard methodology for conducting clinical research. However, IQWiG's terms of reference explicitly disregard any issues which cannot be tested in double-blind studies, for example a comparison of radically different treatment regimes. IQWiG is regarded with skepticism by some doctors in Germany, being seen merely as a mechanism to reduce costs. But the lack of study blinding does increase the risk of bias in these studies. The reason this is important is because patients, if they know they are using a different type of insulin, might behave differently (such as testing blood glucose levels more frequently, for example), which leads to bias in the study results, rendering the results inapplicable to the diabetes population at large. Numerous studies have concluded that any increase in testing of blood glucose levels is likely to yield improvements in glycemic control, which raises questions as to whether any improvements observed in the clinical trials for insulin analogues were the result of more frequent testing or due to the drug undergoing trials.
In 2008, the Canadian Agency for Drugs and Technologies in Health (CADTH) found, in its comparison of the effects of insulin analogues and biosynthetic human insulin, that insulin analogues failed to show any clinically relevant differences, both in terms of glycemic control and adverse reaction profile.
Timeline
1922 Banting and Best use bovine insulin extract on human
1923 Eli Lilly and Company (Lilly) produces commercial quantities of bovine insulin
1923 Hagedorn founds the Nordisk Insulinlaboratorium in Denmark forerunner of Novo Nordisk
1926 Nordisk receives Danish charter to produce insulin as a non-profit
1936 Canadians D.M. Scott and A.M. Fisher formulate zinc insulin mixture and license to Novo
1936 Hagedorn discovers that adding protamine to insulin prolongs the effect of insulin
1946 Nordisk formulates Isophane porcine insulin a.k.a. Neutral Protamine Hagedorn or NPH insulin
1946 Nordisk crystallizes a protamine and insulin mixture
1950 Nordisk markets NPH insulin
1953 Novo formulates Lente porcine and bovine insulins by adding zinc for longer-lasting insulin
1978 Genentech develop biosynthesis of recombinant human insulin in Escherichia coli bacteria using recombinant DNA technology
1981 Novo Nordisk chemically and enzymatically converts porcine insulin to 'human' insulin (Actrapid HM)
1982 Genentech synthetic 'human' insulin approved, in partnership with Eli Lilly and Company, who shepherded the product through the U.S. Food and Drug Administration (FDA) approval process
1983 Lilly produces biosynthetic recombinant "rDNA insulin human INN" (Humulin)
1985 Axel Ullrich sequences the human insulin receptor
1988 Novo Nordisk produces synthetic, recombinant insulin ("insulin human INN")
1996 Lilly Humalog "insulin lispro INN" approved by the U.S. Food and Drug Administration
2003 Aventis Lantus "glargine" insulin analogue approved in USA
2004 Sanofi Aventis Apidra insulin "glulisine" analogue approved in the USA.
2006 Novo Nordisk's Levemir "insulin detemir INN" analogue approved in the USA-
2013 Novo Nordisk's Tresiba "insulin degludec INN" analogue approved in Europe (EMA with additional monitoring]
References
External links
Analog Insulin
Insulin receptor agonists
Drugs developed by Eli Lilly and Company
Human proteins
Recombinant proteins
Peptide hormones
Peptide therapeutics | Insulin analog | [
"Biology"
] | 3,221 | [
"Recombinant proteins",
"Biotechnology products"
] |
3,005,380 | https://en.wikipedia.org/wiki/Disjunctive%20sum | In the mathematics of combinatorial games, the sum or disjunctive sum of two games is a game in which the two games are played in parallel, with each player being allowed to move in just one of the games per turn. The sum game finishes when there are no moves left in either of the two parallel games, at which point (in normal play) the last player to move wins.
This operation may be extended to disjunctive sums of any number of games, again by playing the games in parallel and moving in exactly one of the games per turn. It is the fundamental operation that is used in the Sprague–Grundy theorem for impartial games and which led to the field of combinatorial game theory for partisan games.
Application to common games
Disjunctive sums arise in games that naturally break up into components or regions that do not interact except in that each player in turn must choose just one component to play in. Examples of such games are Go, Nim, Sprouts, Domineering, the Game of the Amazons, and the map-coloring games.
In such games, each component may be analyzed separately for simplifications that do not affect its outcome or the outcome of its disjunctive sum with other games. Once this analysis has been performed, the components can be combined by taking the disjunctive sum of two games at a time, combining them into a single game with the same outcome as the original game.
Mathematics
The sum operation was formalized by . It is a commutative and associative operation: if two games are combined, the outcome is the same regardless of what order they are combined, and if more than two games are combined, the outcome is the same regardless of how they are grouped.
The negation −G of a game G (the game formed by trading the roles of the two players) forms an additive inverse under disjunctive sums: the game G + −G is a zero game (won by whoever goes second) using a simple echoing strategy in which the second player repeatedly copies the first player's move in the other game. For any two games G and H, the game H + G + −G has the same outcome as H itself (although it may have a larger set of available moves).
Based on these properties, the class of combinatorial games may be thought of as having the structure of an abelian group, although with a proper class of elements rather than (as is more standard for groups) a set of elements. For an important subclass of the games called the surreal numbers, there exists a multiplication operator that extends this group to a field.
For impartial misère play games, an analogous theory of sums can be developed, but with fewer of these properties: these games form a commutative monoid with only one nontrivial invertible element, called star (*), of order two.
References
.
Combinatorial game theory | Disjunctive sum | [
"Mathematics"
] | 614 | [
"Recreational mathematics",
"Game theory",
"Combinatorial game theory",
"Combinatorics"
] |
3,005,488 | https://en.wikipedia.org/wiki/Foxconn | Hon Hai Precision Industry Co., Ltd. (), doing business as Hon Hai Technology Group () in Taiwan, Foxconn Technology Group () in Mainland China, and Foxconn () internationally, is a Taiwanese multinational electronics contract manufacturer established in 1974 with headquarters in Tucheng District, New Taipei City, Taiwan. In 2023, the company's annual revenue reached () and was ranked 20th in the 2023 Fortune Global 500. It is the world's largest contract manufacturer of electronics. While headquartered in Taiwan, the company earns the majority of its revenue from assets in China and is one of the largest employers worldwide. Terry Gou is the company founder and former chairman.
Foxconn manufactures electronic products for major American, Canadian, Chinese, Finnish, and Japanese companies. Notable products manufactured by Foxconn include the BlackBerry, iPad, iPhone, iPod, Kindle, all Nintendo gaming systems since the GameCube, Nintendo DS models, Sega models, Nokia devices, Cisco products, Sony devices (including most PlayStation gaming consoles), Google Pixel devices, Xiaomi devices, every successor to Microsoft's Xbox console, and several CPU sockets, including the TR4 CPU socket on some motherboards. As of 2012, Foxconn factories manufactured an estimated 40% of all consumer electronics sold worldwide.
Foxconn named Young Liu its new chairman after the retirement of founder Terry Gou, effective on 1 July 2019. Young Liu was the special assistant to former chairman Terry Gou and the head of business group S (semiconductor). Analysts said the handover signals the company's future direction, underscoring the importance of semiconductors, together with technologies like artificial intelligence, robotics, and autonomous driving, after Foxconn's traditional major business of smartphone assembly has matured.
History
Terry Gou established Hon Hai Precision Industry Co., Ltd. as an electrical components manufacturer in 1974 in Taipei, Taiwan. Foxconn's first manufacturing plant in Mainland China opened in Longhua Town, Shenzhen, in 1988.
One of the important milestones for Foxconn occurred in 2001 when Intel selected the company to manufacture its Intel-branded motherboards instead of Asus. By November 2007, Foxconn further expanded with an announced plan to build a new US$500 million plant in Huizhou, Southern China.
In January 2012, Foxconn named Tien Chong (Terry) Cheng chief executive of its subsidiary FIH Mobile Limited. At this time, Foxconn made up approximately 40% of worldwide consumer electronics production.
Expansion was further pursued after a March 2012 acquisition of a 10-percent stake in the Japanese electronics company Sharp Corporation for US$806 million and to purchase up to 50 percent of the LCDs produced at Sharp's plant in Sakai, Japan. However, the agreed deal was broken as Sharp's shares continued to plunge in the following months. In September 2012, Foxconn announced plans to invest US$494 million in the construction of five new factories in Itu, Brazil, creating 10,000 jobs.
In 2014, the company purchased Asia Pacific Telecom and won some spectrum licenses at an auction, which allowed it to operate 4G telecommunications equipment in Taiwan.
On 25 February 2016, Sharp accepted a ¥700 billion (US$6.24 billion) takeover bid from Foxconn to acquire over 66 percent of Sharp's voting stock. However, as Sharp had undisclosed liabilities which was later informed by Sharp's legal representative to Foxconn, the deal was halted by Foxconn's board of directors. Foxconn asked to call off the deal, but it was proceeded by the former Sharp president. Terry Gou, in the meeting, then wrote the word "義", which means "righteousness", on the whiteboard, saying that Foxconn should honor the deal. A month later, on 30 March 2016, the deal was announced as finalized in a joint press statement, but at a lower price.
In 2016, Foxconn, together with Tencent and luxury-car dealer Harmony New Energy Auto, founded Future Mobility, a car start up that aimed to sell all-electric fully autonomous premium cars by 2020. A Foxconn unit, Foxconn Interconnect Technology, acquired Belkin International for $866m on 26 March 2018.
In July 2019, Foxconn appointed Liu, Young-Way as the new chairman of the Group, which was then ranked 25th among Forbes Top 100 Digital Companies. Soon afterward, Foxconn, led by Young Liu, introduced its "3+3" Model for Transformation, prioritizing the three key industries: electric vehicles, digital health, and robotics industries. The Group is also committed to developing artificial intelligence, semiconductors, and next-generation communication technologies, building blocks in the Group's technology strategy.
In 2020, Foxconn established "Hon Hai Research Institute", with five research centers, each having an average of 40 high technology R&D professionals, all of whom are focused on the research and development of new technologies, the strengthening of Foxconn's technology, and product innovation pipeline, efforts to support the Group's transformation from "brawn" to "brains", and the enhancement of the competitiveness of Foxconn's "3+3" strategy.
Foxconn's 2Q24 revenue was NT$1.551 trillion (US$31.17 billion). Circuits Assembly magazine named Foxconn the largest electronics manufacturing services company in the world for the 14th straight year.
On 5 February 2020, Foxconn started producing medical masks and clothing at its Shenzhen factory in China during the Chinese New Year and the height of the COVID-19 pandemic. The company initially said the masks it makes would be for internal employee use. The outbreak of coronavirus disease 2019 led to a worldwide spike in demand for masks, resulting in global shortages. In a letter to employees, Chairman Young Liu said, "I remember clearly how touching it was when Longhua Park produced our first mask at 4:41am on 5 February. It was the simplest yet most important product Foxconn has ever made. It not only supplied the group's need for epidemic prevention it also contributed to the general public and boosted the morale of the group. All that resulted from our colleagues' hard work."
Following almost a year of public controversy regarding its COVID-19 vaccine shortage; in June 2021, Taiwan agreed to allow founder Terry Gou, through his Yongling Foundation charity, to join with contract chip maker TSMC, and negotiate purchasing COVID-19 vaccines on its behalf. In July 2021, BioNTech's Chinese sales agent Fosun Pharma announced that Foxconn and TSMC had reached an agreement to purchase 10 million BioNTech COVID-19 vaccines from Germany for Taiwan. The two technology manufacturers pledged to each buy five million doses for up to $175 million, for donation to Taiwan's vaccination program.
In 2020, Foxconn initiated MIH Alliance to create an open EV ecosystem that promotes collaboration in the mobility industry, with more than 2,200 companies joining the open standard since its launch. The company announced plans to become more involved as a contract assembler of EVs. In the same year, Foxconn partnered with Fiat Chrysler Automobiles N.V. and Yulon Group for a move into EVs. Foxconn has been holding the Hon Hai Tech Day (HHTD) event since 2020 to showcase its latest achievements. In HHTD21, Foxconn introduced for the first time three self-developed EV models: the Model C recreational vehicle, the Model E sedan, and the Model T electric bus.
In January 2021, Foxconn and Geely Holding Group signed a strategic cooperative agreement and will establish a joint venture company to provide OEM and customized consulting services relating to whole vehicles, parts, intelligent drive systems, and automotive ecosystem platforms to global automotive enterprises and ridesharing companies. In February 2021, it announced an agreement with EV startup Fisker Inc. to jointly produce more than 250,000 vehicles a year. In March 2021, Foxtron, the JV company of Foxconn and Yulon, announced cooperation with Nidec to strengthen the power on EV key component development.
In July 2021, Foxconn teamed up with CTBC Financial Holding Co., Ltd to create a new fund targeting EV investments. In June 2021, Foxconn invested T$995.2 million ($36 million) in Gigasolar Materials Corp to develop EV battery materials. In September 2021, Foxconn collaborated with Thailand's state-owned oil supplier PTT Public Co. to invest US$1–2 billion in launching an EV joint venture in Thailand. In the same month, Foxconn and Gogoro formed a strategic technology and manufacturing partnership to introduce new levels of manufacturing capabilities and scale for Gogoro battery swapping technologies and Smart Scooters. In October 2021, it agreed to purchase a former GM auto plant from Lordstown Motors and to purchase $50 million of the company's common stock. Under the agreement, Foxconn would use the plant to produce Lordstown's Endurance pickup truck. Fisker vehicles would also be made at the same plant.
In January 2022, Foxconn signed an MoU with the Indonesian Ministry of Investment/BKPM, IBC, Indika, and Gogoro to jointly develop a sustainable new energy ecosystem in Indonesia that focuses on electric batteries, electric mobility, and associated industries. In May 2022, Foxconn announced the completion of the Lordstown Motors facility purchase and further signed a contract manufacturing agreement and a joint venture agreement with LMC for product development.
In mid-2021, Foxconn announced that the company will enter into more semiconductor production and will be expanding into supplying chips for electric vehicles (EVs) and electronics equipment used for healthcare. In May 2021, Foxconn and Yageo Group entered into a joint venture agreement to form XSemi Corporation ("XSemi") to extend the businesses into the semiconductor industry, including product development and sales. Based in Hsinchu, Taiwan, XSemi aims to consolidate the strengths and resources of the two market leaders, in addition to the upcoming multifaceted collaborations with leading semiconductor companies in product design, process and capacity planning, and sales channel. In August 2021, Foxconn acquired a Macronix 6-inch Wafer Fab for US$90.8mn.
In February 2022, Foxconn formed a joint venture company with Vedanta Limited, one of India's leading multinational groups, to manufacture semiconductors in India. Foxconn dropped out of the deal in July 2023. In April 2022, it was announced Foxconn had acquired the wireless telecommunications company, arQana Technologies – with the new organization being rebranded as "iCana". Foxconn also announced a merger with the integrated circuit designing firm AchernarTek for an undisclosed amount. The acquisition and consolidation will help Foxconn develop semiconductors for the automotive sector and 5G infrastructure. In September 2022, Foxtron, the automotive division of Foxconn works with Luxgen to launch its first electric vehicle, Luxgen n7.
In 2024, Foxconn surpasses expectations with record fourth-quarter revenue driven by AI demand.
International operations
Foxconn has 137 campuses and offices in 24 countries and areas around the globe. The majority of Foxconn's factories are located in East Asia, with others in Brazil, India, Europe, and Mexico.
China
As of 2012, Foxconn had 12 factories in nine Chinese cities—more than in any other country.
The largest Foxconn factory is located in Longhua Subdistrict, Shenzhen, where hundreds of thousands of workers (varying counts include 230,000, 300,000, and 450,000) are employed at the Longhua Science & Technology Park, a walled campus sometimes referred to as "Foxconn City".
Covering about , the park includes 15 factories, worker dormitories, four swimming pools, fire brigade, own television network (Foxconn TV), city centre with grocery store, bank, restaurants, book store, hospital. While some workers live in surrounding towns and villages, others live and work inside the complex; a quarter of the employees live in the dormitories.
Another Foxconn factory "city" is located at Zhengzhou Technology Park in Zhengzhou, Henan province, where a reported 120,000 workers were employed as of 2012, later, 200,000 workers were employed as of November 2022. The park produces the bulk of Apple's iPhone line and is sometimes referred to as "iPhone City".
Foxconn's future expansion include sites at Wuhan in Hubei province, Kunshan in Jiangsu province, Tianjin, Beijing, Huizhou and Guangzhou in Guangdong province, China. A Foxconn branch that primarily manufactures Apple products is Hongfujin.
On 25 May 2016, the BBC reported that Foxconn replaced 60,000 employees because it had automated "many of the manufacturing tasks associated with their operations". The organization later confirmed those claims.
In September 2017, Foxconn agreed with the Nanjing government to invest US$5.7 billion for the development of intelligent terminal devices, LCD development, and other research.
In July 2021, the Henan floods hit the world's biggest Apple iPhone assembly plant in Zhengzhou, but production was not affected.
On 21 October 2022, and in response to a Covid outbreak at Zhengzhou Technology Park, Foxconn imposed restrictions on its iPhone assembly plant, with dine-in meal facilities closed. On 31 October 2022, after policies intended to control a Covid outbreak prevented workers from leaving the complex, many workers jumped the fence in order to escape. On 2 November 2022, the government imposed the lockdown to the Zhengzhou Airport Economy Zone, where the Foxconn factory is situated. On 23 November, workers clashed with law enforcement over the harsh COVID restrictions and claims that Foxconn failed to provide the salary packages that were promised to new hires. Videos circulated on Chinese social media depicting law enforcement beating protesting workers as well as large crowds of workers fighting back law enforcement.
Brazil
All company facilities in South America are located in Brazil, and these include mobile phone factories in Manaus and Indaiatuba as well as production bases in Jundiaí, Sorocaba, and Santa Rita do Sapucaí. The company is considering further investments in Brazil.
Europe
Foxconn has factories in Hungary, Slovakia, and the Czech Republic. As of 2011 it is the second-largest exporter in the Czech Republic.
India
As of early 2015, Foxconn had tied up with Sony for manufacturing their televisions and selling it all over India. Hence, they started a new plant called Competition Team Technology (India) Private Limited in Irungattukottai (near Poonamallee, Chennai) which was later moved to Oragadam (Kanchipuram) in 2019. As of mid-2015, Foxconn was in talks to manufacture Apple's iPhone in India. In 2015, Foxconn announced that it would be setting up twelve factories in India and would create around one million jobs. It also discussed its intent to work with the Adani Group for expansion in the country. In August 2015, Foxconn invested in Snapdeal. In September 2016, Foxconn started manufacturing products with Gionee. In 2017, Foxconn started the production of iPhones in Sriperumbudur, near Chennai. In April 2019, Foxconn reported that they are ready to mass-produce newer iPhones in India. Its Chairman, Terry Gou, said that the manufacturing will take place in the southern city of Chennai. In September 2022, Foxconn signed a deal for a semiconductor plant in Gujarat with an investment of $21 billion, by Vedanta Group. In July 2023, Foxconn made a decision to quit the project, citing a number of issues with Vedanta Group as well as including external ones. In August 2023, during its annual meeting, Foxconn reportedly stated that India at present accounts for more than 5% of the company's business and there is ample space for future investments. Foxconn has set a target to employ 2 million jobs and meet India's target of exporting mobile phones worth $10 billion, both by 2030. To meet these targets, as of September 2023, the company has three manufacturing plants under construction, all in southern India–a component and semiconductor plant near the company's existing plant in Chennai, and two plants each in Bangalore (near its airport) and Hyderabad (Kongara Kalan) for making iPhones, iPads, iPods and AirPods. All three plants are projected to be completed and begin operations by the end of 2024. They will together employ around 400,000 people in the first five years of their operations.
In November 2023, Foxconn announced a $1.54 billion investment in India to "help it fulfil 'operational needs.'"
In August 2024, Foxconn showed interest in investing in Hyderabad, as confirmed by the Telangana government. Chairman Young Liu met with Chief Minister A Revanth Reddy, discussing plans for a new "fourth city" near Hyderabad.
Japan
Foxconn and Sharp Corporation jointly operate two manufacturing plants specializing in large-screen televisions in Sakai, Osaka. In August 2012, it was reported that Sharp, while doing corporate restructuring and downsizing, was considering selling the plants to Foxconn. The company was believed to be receptive to the plan. The acquisition was completed with a $3.8 billion deal in August 2016.
Malaysia
As of 2011, Foxconn had at least seven factories in the Johor state, at Kulai, where it is developing an industrial park that includes four factories that comprise fully automated assembly lines as well as fully automated packaging lines.
Mexico
Foxconn has a facility in San Jerónimo, Chihuahua that assembles computers, and two facilities in Juáreza former Motorola production base that manufactures mobile phones, and a set-top box factory acquired from Cisco Systems. LCD televisions are also made in the country in Tijuana at a plant acquired from Sony.
On 2 June 2022, Foxconn announced that their Mexico-based production plant had been hit by a ransomware attack in late May, disrupting production. The facility affected was located in Tijuana, Baja California and specializes in the production of consumer electronics, medical devices, and industrial products.
South Korea
The company invested $377 million in June 2014 to pick up a 4.9 percent shareholding in a South Korean IT services provider, SK C&C.
United States
Foxconn announced on 26 July 2017 that it would build a $10 billion TV manufacturing plant in southeastern Wisconsin and would initially employ 3,000 workers (set to increase to 13,000). As part of the agreement, Foxconn was set to receive subsidies ranging from $3 billion to $4.8 billion (paid in increments if Foxconn met certain targets), which would be by far the largest subsidy ever given to a foreign firm in U.S. history. Some estimate that Foxconn is expected to contribute $51.5 billion to Wisconsin's GDP over the next 15 years, which is $3.4 billion annually. However, numerous economists have also expressed skepticism that the benefits would exceed the costs of the deal. Others have noted that Foxconn has made similar claims about job creation in the past which did not come to fruition.
Foxconn was also exempted by Governor Scott Walker from filing an environmental impact statement, prompting criticism from environmentalists. The plant was estimated to contribute significantly to air pollution in the region. Environmentalists criticised the decision to allow Foxconn to draw of water per day from Lake Michigan. Given water concerns, Foxconn is spending $30 million on zero liquid discharge technology. Foxconn is also required to replace wetlands at a higher ratio than other companies; Foxconn must restore 2 acres of wetland for every 1 acre disturbed instead of the ratio of 1.2 to 1 for other companies.
As of 4 October 2017, Foxconn agreed to locate their plant in Mount Pleasant, Wisconsin, and broke ground for the plant 28 June 2018. President Trump was in attendance to promote American manufacturing.
In January 2019, Foxconn said it was reconsidering its initial plans to manufacture LCD screens at the Wisconsin plant, citing high labour costs in the United States.
Under a new agreement announced in April 2021, Foxconn will reduce its planned investment to $672 million with 1,454 new jobs. Tax credits available to the project were reduced to $8 million.
In October 2021, Lordstown Motors announced a $250 million deal to sell a former GM plant to Foxconn, which would become a contract assembler for the company's Endurance pickup truck. The deal was completed in May 2022 for a final price of $230 million. It was announced Foxconn would also invest $50 million into the company through a purchase of common stock.
Major customers
The following list consists of Foxconn's present or past major customers. The list is provided in alphabetical order.
Their country of origin or base of operations is in parentheses.
North America
Amazon.com (United States)
Apple Inc. (United States)
BlackBerry Ltd. (Canada)
Cisco (United States)
Dell (United States)
Fisker Inc (United States)
Google (United States)
Hewlett-Packard (United States)
InFocus (United States)
Intel (United States)
Microsoft (United States)
Motorola Mobility (United States)
Roku, Inc. (United States)
Vizio (United States)
Asia
Acer Inc. (Taiwan)
BBK Electronics (China)
Huawei (China)
Lenovo (China)
Nintendo (Japan)
Sega (Japan)
Sony (Japan)
Toshiba (Japan)
Xiaomi (China)
Europe
HMD Global, under Nokia brand and later rebranded as HMD brand Since 2024.(Finland)
Subsidiaries
FIH Mobile
FIH Mobile is a subsidiary of Foxconn, offering services such as product development and after-sales support. It was incorporated in the tax haven of the Cayman Islands in 2000.
On 18 May 2016, FIH Mobile announced the purchase of Microsoft Mobile's feature phone business. Microsoft Mobile Vietnam is also part of the sale to FIH Mobile, which consists of the Hanoi, Vietnam manufacturing facility. The rest of the business has been sold to a new Finland-based company HMD Global, which started developing and selling new Nokia-branded devices in early 2017. The total sale to both companies amounted to US$350 million. FIH Mobile is now manufacturing new Nokia-branded devices developed by HMD.
Foxtron
Foxtron () is a joint venture of Foxconn and Yulon Group founded in 2020 for vehicular manufacturing and research and development of electric vehicles.
Affiliates
Sharp
Sharp Corporation (シャープ株式会社, Shāpu Kabushiki-gaisha) is a Japanese electronics company. It is headquartered in Sakai, Osaka and was founded by Tokuji Hayakawa in 1912 in Honjo, Tokyo and established as the Hayakawa Metal Works Institute in Abeno, Osaka in 1924. Since 2016, it is majority owned by Taiwan-based manufacturer Hon Hai Precision Industry Co., Ltd., better known as Foxconn.
Controversies
Foxconn has been involved in several controversies relating to employee grievances or treatment. Foxconn has more than a million employees. In China, it employed more people than any other private company
Working conditions
Allegations of poor working conditions have been made on several occasions. News reports highlight the long working hours, discrimination against mainland Chinese workers by their Taiwanese co-workers, and lack of working relationships at the company. Although Foxconn was found to be compliant in the majority of areas when Apple Inc. audited the maker of its iPods and iPhones in 2007, the audit did substantiate several of the allegations. In May 2010, Shanghaiist reported that security guards had been caught beating factory workers.
In reaction to a spate of negative press, particularly that involving worker suicides in which 14 people died from January to May 2010, Steve Jobs defended Apple's relationship with the company in June 2010, citing that its Chinese partner is "pretty nice" and is "not a sweatshop". Meanwhile, however, a report jointly produced by 20 universities in Hong Kong, Taiwan, and mainland China described Foxconn factories as labour camps with widespread worker abuse and illegal overtime.
Concerns increased in early 2012 by an article published in The New York Times in October 2011. It reported evidence that substantiated some of the criticisms. The 2012 audit commissioned by Apple Inc. and performed by the Fair Labor Association found that workers were routinely subjected to inhumane bouts of overtime of up to 34 hours without a pay increase and suggested that debilitating workplace accidents and suicides may be common. A Hong Kong non-profit organisation, Students and Scholars Against Corporate Misbehaviour, has written numerous negative reports on Foxconn's treatment of its employees, such as in 2010 and 2011. These typically find far worse conditions than the 2012 Fair Labour Association audit did, but they rely on a far smaller number of employee informants, circa 100 to 170. The Fair Labor Association audit in 2012 used interviews with 35,000 Foxconn employees.
In January 2012, about 150 Foxconn employees threatened to commit a mass suicide in protest of their working conditions. One worker said the protest resulted from 600 workers being moved into a new "unbearable" factory location. In September 2012, a fight at worker dormitories in Taiyuan, Shanxi, where a guard allegedly was beating a worker, escalated into a riot involving 2,000 people and was quelled by security.
In October 2012, the company admitted that 14-year-old children had worked for a short time at a facility in Yantai, Shandong Province, as part of an internship programme, in violation of the age limit of 16 for legal workers. Foxconn said that the workers had been brought in to help deal with a labor shortage, and Xinhua quoted an official saying that 56 underage interns would be returned to their schools. Reuters quoted Foxconn saying that 2.7 percent of its workforce in China were long- or short-term interns. In response to the scrutiny, Foxconn said it would cut overtime from the current 20 hours per week to less than nine hours a week.
Also in October 2012, there was a crisis concerning an injured worker in which 26-year-old Zhang Tingzhen suffered an electric shock and fell in a factory accident a year earlier. His doctors did immediate surgery to remove part of his brain, "[after which] he lost his memory and can neither speak, walk". When his father attempted to get compensation in 2012, Reuters reported that Foxconn told the family to transport and submit him for a disability assessment in Huizhou 70 km away, or it would cut off funding for his treatment. His doctors protested the move for fear of a brain haemorrhage en route, and the company stated that it was acting within labour laws. His family later sued Foxconn in 2012 and argued in court that Tingzhen had been summoned to the wrong city. In 2014, a court ruled that he had to be assessed in Huizhou to receive compensation, with Foxconn offering a settlement for the father to recant his criticisms, which was refused.
In February 2015, Beijing News reported that an official with the All China Federation of Trade Union (ACFTU), Guo Jun, said that Foxconn allegedly forced employees to work overtime, resulting in occasional death by karōshi or suicide. Jun also said that the illegal overtime resulted from a lack of investigation and light punishments. Foxconn, in return, issued a statement questioning Guo's allegations, arguing workers wanted to work overtime to earn more money.
In November 2017, the Financial Times reported that it had found several students working 11-hour days at the iPhone X plant in Henan province, violating the 40-hour-per-week mandate for children. In response, Foxconn announced that it has stopped the interns' illegal overtime work at the factory in which 3,000 students had been hired that September.
Since 2016, Foxconn has been replacing its workforce with robots, which have replaced 50% of Foxconn's labor force in 2016, and there are plans for completely automated factories.
In 2019, a report was issued by Taiwan News stating that some of Foxconn's managers had fraudulently used rejected parts to build iPhones.
In late 2022, working conditions were exacerbated by Zero-COVID policies leading to protests.
Suicides
Suicides among Foxconn workers have attracted the media's attention. Among the first cases to attract attention in the press was the death of Sun Danyong, a 25-year-old man who committed suicide in July 2009 after reporting the loss of an iPhone 4 prototype in his possession. According to The Telegraph, Danyong had been beaten by security guards.
There was also a series of suicides speculatively linked to low pay in 2010, though employees also noted that Foxconn paid higher wages than similar jobs. In reaction to a spate of worker suicides in which 14 people died in 2010, Foxconn installed suicide-prevention netting at the base of buildings in some facilities and promised to offer substantially higher wages at its Shenzhen production bases. In 2011, Foxconn also hired the PR firm Burson-Marsteller to help deal with the negative publicity from the suicides. That year, the nets seemed to help lower the death rate, although at least four employees died by throwing themselves off buildings.
In January 2012, there was a protest by workers about conditions in Wuhan, with 150 workers threatening to commit mass suicide if factory conditions were not improved. In 2012 and into 2013, three young Foxconn employees were reported to have died by jumping off buildings. In January 2018, another suicide was reported by a factory worker, after 31-year old Li Ming jumped to his death off a building in Zhengzhou, where the iPhone X was being manufactured.
The Wisconsin Valley Project
The project originally committed in 2017 to investing $10 billion and employing up to 13,000 workers but has now shrunk to $672 million with 1,454 jobs.
Food poisoning
On 15 December 2021, 256 workers at Foxconn's Sriperumbudur factory developed Acute Diarrhoeal Disease due to food poisoning after eating food at the company-provided hostel. As a result of which, 159 workers were hospitalized. The workers were provided no information about this, due to which a rumor started spreading among the workers through WhatsApp that two workers had died. By 17 December there were sit-in protests in worker dormitories, by 10 pm of the same day, thousands of women workers of the factory staged protests on the Chennai-Bengaluru national highway, this was met by police detention of 67 women protestors and arrest of one journalist, with many of them being released a day later. Following the protests the factory was shut down for a week, with the state government and district administration investigating the worker conditions. On 22 December the Food Safety Department sealed the kitchen of the dormitory finding rats and poor drainage. The rooms provided to workers were overcrowded, with them being forced to sleep on the floor, some even lacking toilets with a running water supply. Following the revelation of substandard living conditions, on 29 December Apple put the Foxconn plant on probation, with both Apple and Foxconn issuing statements on the dormitory and dining rooms conditions. In January 2022, after assuring Apple and the Tamil Nadu government that it had taken the necessary corrective measures, Foxconn began reopening its factory and resuming work in phases.
Mobility in Harmony Consortium
The Mobility in Harmony Consortium was created in 2020 by Foxconn to promote a set of open standards for electric vehicles.
See also
2010 Chinese labour unrest
List of companies of Taiwan
List of electronics companies
Luxshare
Pegatron
Wistron
References
Further reading
Ngai, Pun, and Jenny Chan. "Global capital, the state, and Chinese workers: The Foxconn experience." Modern China 38.4 (2012): 383–410.
External links
Computer hardware companies
Computer systems companies
Computer companies of Taiwan
Companies listed on the Taiwan Stock Exchange
Electronics companies of Taiwan
Former companies in the Hang Seng Index
Companies in the FTSE China A50 Index
Companies in the S&P Asia 50
Electronics companies established in 1974
Mobile phone manufacturers
Motherboard companies
Electric vehicle industry
Multinational companies headquartered in Taiwan
1974 establishments in Taiwan
Companies in the Taiwan Capitalization Weighted Stock Index
Electronics manufacturing companies | Foxconn | [
"Technology"
] | 6,784 | [
"Computer hardware companies",
"Computer systems companies",
"Computers",
"Computer systems"
] |
3,005,532 | https://en.wikipedia.org/wiki/Tube%20caddy | A tube caddy or tube carrying case is a type of carrying case used for storing and transporting vacuum tubes. They were carried by repair technicians who performed home service calls in the days when radios and television sets were too large and heavy for the average homeowner to bring to a repair shop.
Caddies varied in size and shape, some resembling large briefcases with others resembling tool chests with drawers on the front. Typically they would have rows of square compartments that fit the individually boxed tubes, and often had larger compartments for other components or tools. Most of the space in the caddies was afforded to vacuum tubes (gas-filled tubes were also kept as needed) as most repairs could be effected with the replacement of tubes, with them being some of the few active components in electronic equipment of the time and often being made of glass with sensitive seals they were most likely to break, and were installed in sockets from which they were easy to remove. Some cases were available with built-in tube testers.
The use of tube caddies, along with home visits from repairmen, declined with the use of vacuum tubes themselves as televisions and radios became smaller and cheaper, eliminating a need for repair diagnoses from technicians.
See also
Vacuum tube reliability
Tube tester; Self-service tube tester
References
Vacuum tubes | Tube caddy | [
"Physics"
] | 266 | [
"Vacuum tubes",
"Vacuum",
"Matter"
] |
3,005,578 | https://en.wikipedia.org/wiki/Arming%20plug | An arming plug is a small plug that is fitted into flight hardware to enable functions that, for instrument or personnel safety, should not be activated before flight. In the case of a missile or bomb, the (lack of the) arming plug prevents explosion before flight; in the case of a spacecraft or scientific sounding rocket, it might prevent premature firing of a hydrazine thruster system (hydrazine is extremely toxic) or block cryogenic or photographic film systems from operating before launch.
References
Aerospace engineering
Aircraft components
Rocketry
Spacecraft components
Safety equipment | Arming plug | [
"Astronomy",
"Engineering"
] | 111 | [
"Outer space",
"Astronomy stubs",
"Rocketry",
"Aerospace engineering",
"Outer space stubs"
] |
3,005,633 | https://en.wikipedia.org/wiki/Meagher%20Electronics | Meagher Electronics was a Monterey, California, company which was founded in 1947 by Jim Meagher. It included a recording studio which recorded early demos for Joan Baez, her sister, Mimi Farina and her sister's husband, Richard Farina. The company also repaired all sorts of home entertainment equipment, focusing on professional and semi professional sound equipment and high end home systems. It had a huge, high warehouse space in which literally hundreds of old wooden console radios and phonographs dating back to the 1920s were stacked to the rafters. Meagher used to explain that these had been left by customers who chose not to pick them up instead of paying the repair estimate charges.
The firm was also a commercial sound installation company and one of the first Altec Lansing dealers in the country, with catalogues and equipment going back to 1947. It provided the sound system for most of the concerts and live events in the Monterey area in the 1950s through the 1970s, from folk to jazz to Roger Williams It also recorded the first gold jazz album, Erroll Garner's Concert by the Sea in the mid-1950s on a portable mono Ampex 601 tape recorder which remained a prize possession for many years.
The Monterey Jazz Festival contracted Meagher to provide their sound reinforcement system from the beginning of its existence in 1958 and the firm was extremely conscientious about providing the best quality sound possible, often using recording quality condenser microphones and custom designed loudspeaker arrays. The company supplied sound reinforcement systems for the Big Sur Folk Festivals and assisted Harry McCune Sound from San Francisco and their sound designer Abe Jacob, who was contracted to provide the sound system for the Monterey Pop Festival in 1967.
References
Audio engineering
Companies based in Monterey County, California
Electronics companies established in 1947
1947 establishments in California | Meagher Electronics | [
"Engineering"
] | 366 | [
"Electrical engineering",
"Audio engineering"
] |
3,005,753 | https://en.wikipedia.org/wiki/Scottish%20units | Scottish or Scots units of measurement are the weights and measures peculiar to Scotland which were nominally replaced by English units in 1685 but continued to be used in unofficial contexts until at least the late 18th century. The system was based on the ell (length), stone (mass), and boll and firlot (volume). This official system coexisted with local variants, especially for the measurement of land area.
The system is said to have been introduced by David I of Scotland (1124–53), although there are no surviving records until the 15th century when the system was already in normal use. Standard measures and weights were kept in each burgh, and these were periodically compared against one another at "assizes of measures", often during the early years of the reign of a new monarch. Nevertheless, there was considerable local variation in many of the units, and the units of dry measure steadily increased in size from 1400 to 1700.
The Scots units of length were technically replaced by the English system by an Act of the Parliament of Scotland in 1685, and the other units by the Treaty of Union with England in 1706. However, many continued to be used locally during the 18th and 19th centuries. The introduction of the Imperial system by the Weights and Measures Act 1824 (5 Geo. 4. c. 74) saw the end of any formal use in trade and commerce, although some informal use as customary units continued into the 20th century. "Scotch measure" or "Cunningham measure" was brought to parts of Ulster in Ireland by Ulster Scots settlers, and used into the mid-19th century.
Length
Scottish inch The Scottish inch was 25.44 mm, almost the same as the English (and modern international) inch (25.40 mm). A fraudulent smaller inch of ell (22.4 mm) is also recorded.
foot (Scots: ) 12 inches (305.3 mm; compare with the English foot of 304.8 mm).
yard () 36 inches (915.9 mm; compare with the English yard of 914.4 mm). Rarely used except with English units, although it appears in an Act of Parliament from 1432: "The king's officer, as is foresaid, shall have a horn, and each one a red wand of three-quarters of a yard at least."
Scots ell The ell () was the basic unit of length, equal to 37 inches (941.3 mm). The "Barony ell" of 42 inches (1069 mm) was used as the basis for land measurement in the Four Towns area near Lochmaben, Dumfriesshire.
fall () 6 ells, or 222 inches (5.648 m). Identical to the Scots rod and ("rope").
Scots mile 320 falls or 5920 feet (1807 metres, compare with the English mile of 5280 English feet or approximately 1609 metres), but varied from place to place. Obsolete by the 19th century.
Area
A number of conflicting systems were used for area, sometimes bearing the same names in different regions, but working on different conversion rates. Because some of the systems were based on what land would produce, rather than the physical area, they are listed in their own section. Please see individual articles for more specific information. Because fertility varied widely, in many areas, production was considered a more practical measure.
Area by size
For information on the squared units, please see the appropriate articles in the length section
square inch
square ell
square fall ()
Scots rood ()
Scots acre
Area by production
Eastern Scotland:
oxgang () The area an ox could plough in a year (around 20 acres).
ploughgate () 8 oxgangs
davoch (, or ) 4 ploughgates
Area by taxation/rent
In western Scotland, including Galloway:
markland (, ) 8 ouncelands (varied)
ounceland (, ) 20 pennylands
pennyland () basic unit; sub-divided into halfpenny-land and farthing-land.
Also:
quarterland ( Of variable value: one-quarter of a Markland.
groatland (Scottish Gaelic, ) Land valued at a groat i.e. four pence
Volume
Dry volume
Dry volume measures were slightly different for various types of grain, but often bore the same name.
chalder () Normally understood as 16 bolls (being just under 12 Winchester quarters)
boll (, or ) Equal to 4 firlots.
firlot
peck
lippie, or forpet
These volume measurements were fixed at slightly different sizes at different times. A unified weights and measures system is attributed to David I – though the first written records of this are from the 14th century. The Assize of 1426 made changes to these measures. Then the Assize of 1457 was followed by four major revisions. These involved increases in the size of the firlot, the basic unit of grain measure, and occurred in: c.1500, 1555 (modified in 1563), 1587 and 1618. This last date gave a fixed Scottish system which only changed with the introduction of English measures. An increase in the size of the firlot allowed greater taxation to be raised (as each unit collected was bigger).
Superimposed on this chronological complexity was the difference between the "legal" measures established by the assizes, and the actual measures used in the markets and everyday trade. The "trading" measure could be one sixteenth larger than the "legal" boll, and the "customary" boll a further one sixteenth larger.
Weight equivalents of one boll are given in a trade dictionary of 1863 as follows:
Flour 140 pounds;
Peas or beans 280 pounds;
Oats 264 pounds;
Barley 320 pounds;
Oatmeal 140 pounds.
Fluid volume
Nipperkin was also used, but perhaps not part of this more formal set.
Weight
Weight was measured according to "troy measure" (Lanark) and "tron measure" (Edinburgh), which were standardised in 1661. In the Troy system these often bore the same name as imperial measures.
drop ()
ounce ()
pound ()
stone ()
Various local measures all existed, often using local weighing stones.
See also the weight meanings of the under the dry volume section, above.
See also
Units of measurement
Systems of measurement
History of measurement
Scottish coinage
Scottish pronunciation
Tron
Bibliography
Collins Encyclopedia of Scotland
Weights and Measures, by D. Richard Torrance, SAFHS, Edinburgh, 1996, (NB book focuses on Scottish weights and measures exclusively)
Scottish National Dictionary and Dictionary of the Older Scottish Tongue
Weights and Measures in Scotland: A European Perspective R. D. Connor, et al. National Museum of Scotland and Tuckwell Press, NMSE Publishing, 2004,
References
External links
Scottish Weights and Measures on Scottish Archive network (SCAN)
Scottish
Medieval history of Scotland
Early modern history of Scotland
Systems of units
Units of measurement by country | Scottish units | [
"Mathematics"
] | 1,414 | [
"Obsolete units of measurement",
"Systems of units",
"Units of measurement by country",
"Quantity",
"Units of measurement"
] |
3,005,810 | https://en.wikipedia.org/wiki/Transderivational%20search | Transderivational search (often abbreviated to TDS) is a psychological and cybernetics term, meaning when a search is being conducted for a fuzzy match across a broad field. In computing the equivalent function can be performed using content-addressable memory.
Unlike usual searches, which look for literal (i.e. exact, logical, or regular expression) matches, a transderivational search is a search for a possible meaning or possible match as part of communication, and without which an incoming communication cannot be made any sense of whatsoever. It is thus an integral part of processing language, and of attaching meaning to communication.
In NLP (Neuro-liguistic Programming), a transderivational search (Bandler and Grinder, 1976) is essentially the process of searching back through one's stored memories and mental representations to find the personal reference experiences from which a current understanding or mental map has been derived.
By the end of 1976, Grinder and Bandler had combined Satir’s and Perls’ language patterns and Erickson’s hypnotic language and use of metaphor with anchoring to create new processes that they called collapsing anchors, trans-derivational search, changing personal history, and reframing.
A psychological example of TDS is in Ericksonian hypnotherapy, where vague suggestions are used that the patient must process intensely in order to find their own meanings, thus ensuring that the practitioner does not intrude his own beliefs into the subject's inner world.
TDS in human communication and processing
Because TDS is a compelling, automatic and unconscious state of internal focus and processing (i.e. a type of everyday trance state), and often a state of internal lack of certainty, or openness to finding an answer (since something is being checked out at that moment), it can be utilized or interrupted, in order to create, or deepen, trance.
TDS is a fundamental part of human language and cognitive processing. Arguably, every word or utterance a person hears, for example, and everything they see or feel and take note of, results in a very brief trance while TDS is carried out to establish a contextual meaning for it.
Examples
Leading statements:
"And those thoughts you had yesterday..." the human mind cannot process hearing this phrase, without at some level searching internally for some thoughts or other that it had yesterday, to make the subject of the sentence.
"The many colors that fruit can be" likewise starts the human mind considering even if briefly, different fruit sorted by color.
"You did it again, didn't you!" This everyday manipulative use of TDS usually sends the recipient looking internally for some "it" they may have done for which blame is being fairly given. Regardless of whether such a matter can be identified, guilt or anger may result.
"There has been pain, hasn't there" the mind of a patient suffering an illness will find it very hard or impossible to hear or answer this sentence without conducting internal searches to verify whether this is true or not, or to find an example if so.
"You'd forgotten something [or: some part of your body], hadn't you?" the mind usually checks through the various things, or parts of the body, on hearing this, seeing if each in turn has been forgotten.
Textual ambiguity:
"Do you remember line dancing on the steps?" Without sufficient context, some statements may trigger TDS in order to resolve inherent ambiguity in the interpretation of a posed question. Do I remember a bygone fad called "line dancing on the steps"? Do I remember personally engaging in dancing in the past? Do I remember my routine practice dancing by focusing on the steps of the dance? Do I tend to forget about dancing when I am standing on steps?
"Penny-wise and pound the table dance to the beat of a different drummer". The mixing of cliché and stock phrases may trigger TDS in order to reconcile the discrepancies between expected and actual utterances in sequence.
Although TDS is often associated with spoken language, it can be induced in any perceptual system. Thus Milton Erickson's "hypnotic handshake" is a technique that leaves the other person performing TDS in search of meaning to a deliberately ambiguous use of touch.
References
See also
Ambiguity
Milton Erickson
Hypnosis
Linguistics
Presupposition
Artificial intelligence
Natural language processing
Information extraction
Content-addressable memory
Garden path sentence
Communication
Natural language processing
Generative linguistics
Psycholinguistics
Syntactic entities | Transderivational search | [
"Technology"
] | 937 | [
"Natural language processing",
"Natural language and computing"
] |
3,005,828 | https://en.wikipedia.org/wiki/Adaptive%20beamformer | An adaptive beamformer is a system that performs adaptive spatial signal processing with an array of transmitters or receivers. The signals are combined in a manner which increases the signal strength to/from a chosen direction. Signals to/from other directions are combined in a benign or destructive manner, resulting in degradation of the signal to/from the undesired direction. This technique is used in both radio frequency and acoustic arrays, and provides for directional sensitivity without physically moving an array of receivers or transmitters.
Motivation/Applications
Adaptive beamforming was initially developed in the 1960s for the military applications of sonar and radar. There exist several modern applications for beamforming, one of the most visible applications being commercial wireless networks such as LTE. Initial applications of adaptive beamforming were largely focused in radar and electronic countermeasures to mitigate the effect of signal jamming in the military domain.
Radar uses can be seen here Phased array radar. Although not strictly adaptive, these radar applications make use of either static or dynamic (scanning) beamforming.
Commercial wireless standards such as 3GPP Long Term Evolution (LTE (telecommunication)) and IEEE 802.16 WiMax rely on adaptive beamforming to enable essential services within each standard.
Basic Concepts
An adaptive beamforming system relies on principles of wave propagation and phase relationships. See Constructive interference, and Beamforming. Using the principles of superimposing waves, a higher or lower amplitude wave is created (e.g. by delaying and weighting the signal received). The adaptive beamforming system dynamically adapts in order to maximize or minimize a desired parameter, such as Signal-to-interference-plus-noise ratio.
Adaptive Beamforming Schemes
There are several ways to approach the beamforming design, the first approach was implemented by maximizing the signal to noise ratio (SNR) by Applebaum 1965. This technique adapts the system parameters in order to maximize the receive signal power, while minimizing noise (such as interference or jamming). Another approach is the Least Mean Squares (LMS) error method implemented by Widrow, and Maximum Likelihood Method (MLM), developed in 1969 by Capon. Both the Applebaum and the Widrow algorithms are very similar, and converge toward an optimal solution. However, these techniques have implementation drawbacks. In 1974, Reed demonstrated a technique known as Sample-Matrix Inversion (SMI). SMI determines the adaptive antenna array weights directly, unlike the algorithms of Applebaum and Widrow.
A detailed explanation of the adaptive techniques introduced above can be found here:
Least Mean Squares Algorithm
Sample Matrix Inversion Algorithm
Recursive Least Square Algorithm
Conjugate gradient method
Constant Modulus Algorithm
See also
Beamforming is spatial signal processing which makes spatial beam focused on the target direction and spatial beam nulled interference signal.
Smart Antennas is multiple antenna systems having one of three structures which are single-input and multiple-output (SIMO), multiple-input and single-output (MISO), and multiple-input and multiple-output (MIMO) structures.
MIMO is an advanced smart antenna system which has multiple transmit antennas at the transmitter and multiple receive antennas at the receiver.
References
Signal processing
Multidimensional signal processing | Adaptive beamformer | [
"Technology",
"Engineering"
] | 663 | [
"Telecommunications engineering",
"Computer engineering",
"Signal processing"
] |
3,005,906 | https://en.wikipedia.org/wiki/Information%20privacy%20law | Information privacy, data privacy or data protection laws provide a legal framework on how to obtain, use and store data of natural persons. The various laws around the world describe the rights of natural persons to control who is using their data. This includes usually the right to get details on which data is stored, for what purpose and to request the deletion in case the purpose is not given anymore.
Over 80 countries and independent territories, including nearly every country in Europe and many in Latin America and the Caribbean, Asia, and Africa, have now adopted comprehensive data protection laws. The European Union has the General Data Protection Regulation (GDPR), in force since May 25, 2018. The United States is notable for not having adopted a comprehensive information privacy law, but rather having adopted limited sectoral laws in some areas like the California Consumer Privacy Act (CCPA).
By Jurisdiction
The German state of Hessia enacted the world's first data privacy law on September 30, 1970. In Germany the term informational self-determination was first used in the context of a German constitutional ruling relating to personal information collected during the 1983 census.
Asia
India
India passed its Digital Personal Data Protection Act, 2023 in August 2023.
China
China passed its Personal Information Protection Law (PIPL) in mid-2021, and was effective from November 1, 2021. It focuses heavily on consent, rights of the individual, and transparency of data processing. PIPL has been compared to the EU GDPR as it has similar scope and many similar provisions.
Philippines
In the Philippines, The Data Privacy Act of 2012 mandated the creation of the National Privacy Commission that would monitor and maintain policies that involve information privacy and personal data protection in the country. Modeled after the EU Data Protection Directive and the Asia-Pacific Economic Cooperation (APEC) Privacy Framework, the independent body would ensure compliance of the country with international standards set for data protection. The law requires government and private organizations composed of at least 250 employees or those which have access to the personal and identifiable information of at least 1000 people to appoint a Data Protection Officer that would assist in regulating the management of personal information in such entities.
In summary, the law identifies important points regarding the handling of personal information as follows:
Personal information must be collected for reasons that are specified, legitimate, and reasonable.
Personal information must be handled properly. Information must be kept accurate and relevant, used only for the stated purposes, and retained only for as long as reasonably needed. The law required entities to be active in ensuring that unauthorized parties do not have access to their customers' information.
Personal information must be disposed in way that unauthorized third parties could not access the discarded data.
Sri Lanka
In early 2022, Sri Lanka became the first country in South Asia to enact comprehensive data privacy legislation. The Personal Data Protection Act No. 9 of 2022, effective since March 19, 2022, applies to processing within Sri Lanka and extends extraterritorially to controllers or processors offering goods and services to individuals in Sri Lanka and/or monitoring their behavior in the country.
Europe
The right to data privacy is relatively heavily regulated and actively enforced in Europe. Article 8 of the European Convention on Human Rights (ECHR) provides a right to respect for one's "private and family life, his home and his correspondence", subject to certain restrictions. The European Court of Human Rights has given this article a very broad interpretation in its jurisprudence. According to the Court's case law the collection of information by officials of the state about an individual without their consent always falls within the scope of Article 8. Thus, gathering information for the official census, recording fingerprints and photographs in a police register, collecting medical data or details of personal expenditures, and implementing a system of personal identification has been judged to raise data privacy issues. What also falls under "privacy-sensitive data" under the GDPR is such information as racial or ethnic origin, political opinions, religious or philosophical beliefs and information regarding a person's sex life or sexual orientation.
Any state interference with a person's privacy is only acceptable for the Court if three conditions are fulfilled:
The interference is in accordance with the law
The interference pursues a legitimate goal
The interference is necessary in a democratic society
The government is not the only entity which may pose a threat to data privacy. Other citizens, and private companies most importantly, may also engage in threatening activities, especially since the automated processing of data became widespread. The Convention for the Protection of Individuals with regard to Automatic Processing of Personal Data was concluded within the Council of Europe in 1981. This convention obliges the signatories to enact legislation concerning the automatic processing of personal data, which many duly did.
As all the member states of the European Union are also signatories of the European Convention on Human Rights and the Convention for the Protection of Individuals with regard to Automatic Processing of Personal Data, the European Commission was concerned that diverging data protection legislation would emerge and impede the free flow of data within the EU zone. Therefore, the European Commission decided to propose harmonizing data protection law within the EU. The resulting Data Protection Directive was adopted by the European Parliament and ministers from national governments in 1995 and had to be transposed into national law by the end of 1998.
The directive contains a number of key principles with which member states must comply. Anyone processing personal data must comply with the eight enforceable principles of good practice. They state that the data must be:
Fairly and lawfully processed.
Processed for limited purposes.
Adequate, relevant and not excessive.
Accurate.
Kept no longer than necessary.
Processed in accordance with the data subject's rights.
Secure.
Transferred only to countries with adequate protection.
Personal data covers both facts and opinions about the individual. It also includes information regarding the intentions of the data controller towards the individual, although in some limited circumstances exemptions will apply. With processing, the definition is far wider than before. For example, it incorporates the concepts of "obtaining", "holding" and "disclosing".
All EU member states adopted legislation pursuant this directive or adapted their existing laws. Each country also has its own supervisory authority to monitor the level of protection.
Because of this, in theory the transfer of personal information from the EU to the US is prohibited when equivalent privacy protection is not in place in the US. American companies that would work with EU data must comply with the Safe Harbour framework. The core principles of data protected are limited collection, consent of the subject, accuracy, integrity, security, subject right of review and deletion. As a result, customers of international organizations such as Amazon and eBay in the EU have the ability to review and delete information, while Americans do not. In the United States the equivalent guiding philosophy is the Code of Fair Information Practice (FIP).
The difference in language here is important: in the United States the debate is about privacy where in the European Community the debate is on data protection. Moving the debate from privacy to data protection is seen by some philosophers as a mechanism for moving forward in the practical realm while not requiring agreement on fundamental questions about the nature of privacy.
France
France adapted its existing law, "no. 78-17 of 6 January 1978 concerning information technology, files and civil liberties".
Germany
In Germany, both the federal government and the states enacted legislation.
Switzerland
While Switzerland is not a member of the European Union (EU) or of the European Economic Area (EEA), it has partially implemented the EU Directive on the protection of personal data in 2006 by acceding to the STE 108 agreement of the Council of Europe and a corresponding amendment of the federal Data Protection Act. However, Swiss law imposes less restrictions upon data processing than the Directive in several respects.
In Switzerland, the right to privacy is guaranteed in article 13 of the Swiss Federal Constitution. The Swiss Federal Data Protection Act (DPA) and the Swiss Federal Data Protection Ordinance (DPO) entered into force on July 1, 1993. The latest amendments of the DPA and the DPO entered into force on January 1, 2008.
The DPA applies to the processing of personal data by private persons and federal government agencies. Unlike the data protection legislation of many other countries, the DPA protects both personal data pertaining to natural persons and legal entities.
The Swiss Federal Data Protection and Information Commissioner in particular supervises compliance of the federal government agencies with the DPA, provides advice to private persons on data protection, conducts investigations and makes recommendations concerning data protection practices.
Some data files must be registered with the Swiss Federal Data Protection and Information Commissioner before they are created. In the case of a transfer of personal data outside of Switzerland, special requirements need to be met and, depending on the circumstances, the Swiss Federal Data Protection and Information Commissioner must be informed before the transfer is made.
Most Swiss cantons have enacted their own data protection laws regulating the processing of personal data by cantonal and municipal bodies.
United Kingdom
In the United Kingdom the Data Protection Act 1998 (c 29) (Information Commissioner) implemented the EU Directive on the protection of personal data . It replaced the Data Protection Act 1984 (c 35). The 2016 General Data Protection Regulation supersedes previous Protection Acts. The Data Protection Act 2018 (c 12) updates data protection laws in the UK. It is a national law which complements the European Union's General Data Protection Regulation (GDPR).
North America
Canada
In Canada, the Personal Information Protection and Electronic Documents Act (PIPEDA) went into effect on 1 January 2001, applicable to private bodies which are federally regulated. All other organizations were included on 1 January 2004. The PIPEDA brought Canada into compliance with EU data protection law, although civil society, regulators, and academics have claimed that it does not address modern challenges of privacy law as well as the GDPR does, calling for reform.
The PIPEDA specifies the rules to govern collection, use, or disclosure of the personal information in the course of recognizing the right of privacy of individuals with respect to their personal information. It also specifies the rules for the organizations to collect, use, and disclose personal information.
The PIPEDA applies to:
The organizations collect, uses, or disclosure in the matter of commercial use.
The organizations and the employee of the organization collect, use, or discloses in the course of operation of a federal work, undertaking, or business.
The PIPEDA does not apply to:
Government institutions to which the Privacy Act applies.
Individuals who collect, use, or disclose personal information for personal purpose and use.
Organizations which collect, use, or disclose personal information only for journalistic, artistic or literary purposes.
As specified in the PIPEDA:
"Personal Information" means information about an identifiable individual, but does not include the name, title, or business address or telephone number of an employee of an organization.
"Organization" means an association, a partnership, a person and a trade union.
"Federal work, undertaking or business" means any work, undertaking or business that is within the legislative authority of Parliament, including:
a work, undertaking or business that is operated or carried on for or in connection with navigation and shipping, whether inland or maritime, including the operation of ships and transportation by ship anywhere in Canada;
a railway, canal, telegraph or other work or undertaking that connects a province with another province, or that extends beyond the limits of a province;
a line of ships that connects a province with another province, or that extends beyond the limits of a province;
a ferry between a province and another province or between a province and a country other than Canada;
aerodromes, aircraft or a line of air transportation;
a radio broadcasting station;
a bank;
a work that, although wholly situated within a province, is before or after its execution declared by Parliament to be for the general advantage of Canada or for the advantage of two or more provinces;
a work, undertaking or business outside the exclusive legislative authority of the legislatures of the provinces; and
a work, undertaking or business to which federal laws, within the meaning of section 2 of the Oceans Act, apply under section 20 of that Act and any regulations made under paragraph 26(1)(k) of that Act.
The PIPEDA gives individuals the right to:
understand the reasons why organizations collect, use, or disclose personal information.
expect organizations to collect, use or disclose personal information in a reasonable and appropriate way.
understand who in the organizations pays the responsibility for protecting individuals' personal information.
expect organizations to protect the personal information in a reasonable and secure way.
expect the personal information held by the organizations to be accurate, complete, and up-to-date.
have the access to their personal information and ask for any corrections or have the right to make complain towards the organizations.
The PIPEDA requires organizations to:
obtain consent before they collect, use, and disclose any personal information.
collect personal information in a reasonable, appropriate, and lawful ways.
establish personal information policies that are clear, reasonable, and ready to protect individuals' person information.
United States
Data privacy is not highly legislated or regulated in the U.S. In the United States, access to private data contained in, for example, third-party credit reports may be sought when seeking employment or medical care, or making automobile, housing, or other purchases on credit terms. Although partial regulations exist, there is no all-encompassing law regulating the acquisition, storage, or use of personal data in the U.S. In general terms, in the U.S., whoever can be troubled to key in the data, is deemed to own the right to store and use it, even if the data was collected without permission, except to any extent regulated by laws and rules such as the federal Communications Act's provisions, and implementing rules from the Federal Communications Commission, regulating use of customer proprietary network information (CPNI). For instance, the Health Insurance Portability and Accountability Act of 1996 (HIPAA), the Children's Online Privacy Protection Act of 1998 (COPPA), and the Fair and Accurate Credit Transactions Act of 2003 (FACTA), are all examples of U.S. federal laws with provisions which tend to promote information flow efficiencies.
The Supreme Court interpreted the Constitution to grant a right of privacy to individuals in Griswold v. Connecticut. Very few states, however, recognize an individual's right to privacy, a notable exception being California. An inalienable right to privacy is enshrined in the California Constitution's article 1, section 1, and the California legislature has enacted several pieces of legislation aimed at protecting this right. The California Online Privacy Protection Act (OPPA) of 2003 requires operators of commercial web sites or online services that collect personal information on California residents through a web site to conspicuously post a privacy policy on the site and to comply with its policy.
An early attempt to create rules around the use of information in the U.S. was the fair information practice guidelines developed by the Department for Health, Education and Welfare (HEW) (later renamed Department of Health & Human Services (HHS)), by a Special Advisory Committee on Automated Personal Data Systems, under the chairmanship of computer pioneer and privacy pioneer Willis H. Ware. The report submitted by the Chair to the HHS Secretary titled "Records, Computers and Rights of Citizens (07/01/1973)", proposes universal principles for the privacy and protection of consumer and citizen data:
For all data collected, there should be a stated purpose.
Information collected from an individual cannot be disclosed to other organizations or individuals unless specifically authorized by law or by consent of the individual.
Records kept on an individual should be accurate and up to date.
There should be mechanisms for individuals to review data about them, to ensure accuracy. This may include periodic reporting.
Data should be deleted when it is no longer needed for the stated purpose.
Transmission of personal information to locations where "equivalent" personal data protection cannot be assured is prohibited.
Some data is too sensitive to be collected, unless there are extreme circumstances (e.g., sexual orientation, religion).
The safe harbor arrangement was developed by the United States Department of Commerce in order to provide a means for U.S. companies to demonstrate compliance with European Commission directives and thus to simplify relations between them and European businesses.
HIPAA
The Health Insurance Portability and Accountability Act (HIPAA) was enacted by the U.S. Congress in 1996. HIPAA is also known as the Kennedy-Kassebaum Health Insurance Portability and Accountability Act (HIPAA-Public Law 104-191), effective August 21, 1996. The basic idea of HIPAA is that an individual who is a subject of individually identifiable health information should have:
Established procedures for the exercise of individual health information privacy rights.
The use and disclosure of individual health information should be authorized or required.
One difficulty with HIPAA is that there must be a mechanism to authenticate the patient who demands access to his/her data. As a result, medical facilities have begun to ask for Social Security Numbers from patients, thus arguably decreasing privacy by simplifying the act of correlating health records with other records. The issue of consent is problematic under HIPAA, because the medical providers simply make care contingent upon agreeing to the privacy standards in practice.
FCRA
The Fair Credit Reporting Act applies the principles of the Code of Fair Information Practice to credit reporting agencies. The FCRA allows individuals to opt out of unwanted credit offers:
Equifax (888) 567-8688 Equifax Options, P.O. Box 740123 Atlanta GA 30374-0123.
Experian (800) 353-0809 or (888) 5OPTOUT P.O. Box 919, Allen, TX 75013
TransUnion (800) 680-7293 or (888) 5OPTOUT P.O Box 97328, Jackson, MS 39238.
Because of the Fair and Accurate Credit Transactions Act, each person can obtain a free annual credit report.
The Fair Credit Reporting Act has been effective in preventing the proliferation of specious so-called private credit guides. Before 1970, private credit guides offered detailed, if unreliable, information on easily identifiable individuals. Before the Fair Credit Reporting Act, salacious unsubstantiated material could be included – and in fact, gossip was widely included in credit reports. EPIC has a FCRA page. The Consumer Data Industry Association, which represents the consumer reporting industry, also has a website with FCRA information.
The Fair Credit Reporting Act provides consumers the ability to view, correct, contest, and limit the uses of credit reports. The FCRA also protects the credit agency from the charge of negligent release in the case of misrepresentation by the requester. Credit agencies must ask the requester the purpose of a requested information release, but need to make no effort to verify the truth of the requester's assertions. In fact, the courts have ruled that, "The Act clearly does not provide a remedy for an illicit or abusive use of information about consumers" (Henry v Forbes, 1976). It is widely believed that in order to avoid the FCRA, ChoicePoint was created by Equifax at which time the parent company copied all its records to its newly created subsidiary. ChoicePoint is not a credit reporting agency, and thus FCRA does not apply.
The Fair Debt Collection Practices Act similarly limits dissemination of information about a consumer's financial transactions. It prevents creditors or their agents from disclosing the fact that an individual is in debt to a third party, although it allows creditors and their agents to attempt to obtain information about a debtor's location. It limits the actions of those seeking payment of a debt. For example, debt collection agencies are prohibited from harassment or contacting individuals at work. The Bankruptcy Abuse Prevention and Consumer Protection Act of 2005 (which actually gutted consumer protections, for example in case of bankruptcy resulting from medical cost) limited some of these controls on debtors.
ECPA
The Electronic Communications Privacy Act (ECPA) establishes criminal sanctions for interception of electronic communication. However, the legislation has been criticized for lack of impact due to loopholes.
Computer security, privacy and criminal law
The following summarized some of the laws, regulations and directives related to the protection of information systems:
1970 U.S. Fair Credit Reporting Act
1970 U.S. Racketeer Influenced and Corrupt Organization (RICO) Act
1974 Family Educational Rights and Privacy Act (FERPA)
1974 U.S. Privacy Act
1980 Organization for Economic Cooperation and Development (OECD) Guidelines
1984 U.S. Medical Computer Crime Act
1984 U.S. Federal Computer Crime Act (strengthened in 1986 and 1994)
1986 U.S. Computer Fraud and Abuse Act (amended in 1986, 1994, 1996 and 2001)
1986 U.S. Electronic Communications Privacy Act (ECPA)
1987 U.S. Computer Security Act (Repealed by the Federal Information Security Management Act of 2002)
1988 U.S. Video Privacy Protection Act
1990 United Kingdom Computer Misuse Act
1991 U.S. Federal Sentencing Guidelines
1992 OECD Guidelines to Serve as a Total Security Framework
1994 Communications Assistance for Law Enforcement Act
1995 Council Directive on Data Protection for the European Union (EU)
1996 U.S. Economic and Protection of Proprietary Information Act
1996 Health Insurance Portability and Accountability Act (HIPAA) (requirement added in December 2000)
1998 U.S. Digital Millennium Copyright Act (DMCA)
1999 U.S. Uniform Computer Information Transactions Act (UCITA)
2000 U.S. Congress Electronic Signatures in Global National Commerce Act ("ESIGN")
2001 Uniting and Strengthening America by Providing Appropriate Tools to Restrict, Intercept and Obstruct Terrorism (USA PATRIOT) Act
2002 Homeland Security Act (HSA)
2002 Federal Information Security Management Act of 2002
Several US federal agencies have privacy statutes that cover their collection and use of private information. These include the Census Bureau, the Internal Revenue Service, and the National Center for Education Statistics (under the Education Sciences Reform Act). In addition, the CIPSEA statute protects confidentiality of data collected by federal statistical agencies.
State-specific laws
Lawmakers in several states have proposed legislation to change the way online businesses handle user information. Among those generating significant attention are several Do Not Track legislation and the Right to Know Act (California Bill AB 1291). The California Right to Know Act, if passed, would require every business which keeps user information to provide its user a copy of stored information when requested. The bill faced heavy oppositions from trade groups representing companies such as Google, Microsoft, and Facebook, and failed to pass.
Arkansas
Arkansas has a biometric data privacy law.
California
On June 28, 2018 California legislature passed AB 375, the California Consumer Privacy Act of 2018, effective January 1, 2020. In November 2020, Proposition 24, also known as the California Privacy Rights Act, amended and expanded the CCPA. The law specifically protects employee data.
Florida
On June 6, 2023, Florida enacted Florida Senate Bill 262, effective July 1, 2024. It gives consumers the right to confirm whether businesses with over $1 billion in gross annual revenue who derive more than half of their revenue from online ads collected data about them and control over the data, including correction and deletion. The law also prohibits government agencies from asking a social media companies to censor content or remove users from its platform.
Illinois
On October 3, 2008, Illinois enacted the Biometric Information Privacy Act. The law was the first in the nation to regulate biometric data. The law requires private businesses to obtain consent to collect or disclose the biometric identifiers of consumers. The law also requires the data be securely stored and destroyed in a timely manner. The law specifically protects employee data.
New York
In 2021, New York enacted a commercial biometric data privacy law that requires businesses to conspicuously notify consumers of data collection. The law bars employers from collecting biometric data from employees.
Texas
In 2009, Texas enacted a consumer law requiring consent for biometric data for commercial use to be leased, sold, or disclosed. The law also requires the data be destroyed within one year of collection.
Washington
In 2017, Washington enacted a specific consumer biometric data privacy law covering commercial use.
On April 27, 2023, Washington enacted the My Health, My Data Act, effective March 31, 2024. The law was the first in the nation to regulate consumer health data not protected by HIPAA. The law requires companies to obtain prior authorization to obtain, share, or sell health data, including data that can be used to infer or linked to health status, such as purchasing medications or digestion tracking. The law guarantees the right to withdraw consent and request deletion. The law also prohibits geo-fences around healthcare facilities.
South America
Brazil
Brazil's General Personal Data Protection Law (LGPD) became law on September 18, 2020. The law's primary aim is to unify 40 different Brazilian laws that regulate the processing of personal data. The bill has 65 articles and has many similarities to the GDPR.
"Safe Harbor" Privacy Framework
Unlike the U.S. approach to privacy protection, which relies on industry-specific legislation, regulation and self-regulation, the European Union relies on the comprehensive privacy legislation. The European Directive on Data Protection that went into effect in October 1998, includes, for example, the requirement to create government data protection agencies, registration of databases with those agencies, and in some instances prior approval before personal data processing may begin. In order to bridge these different privacy approaches and provide a streamlined means for U.S. organizations to comply with the Directive, the U.S. Department of Commerce in consultation with the European Commission developed a "safe harbor" framework. In order for the framework to be enforced, companies must publicly publish a privacy policy.
See also
Canadian privacy law
Center for Democracy and Technology
Data care
Data localization
Data sovereignty
Do Not Track legislation
Privacy Commissioner of Canada
Privacy International
Privacy laws of the United States
Right to be forgotten
References
Further reading
Warren S. and Brandeis L., 1890, "The right to privacy," Harvard Law Review, Vol. 4, 193-220.
Graham Greenleaf, Global Data Privacy Laws: 89 Countries, and Accelerating http://ssrn.com/abstract=2000034
Computer law
Data laws
Information privacy
Privacy law | Information privacy law | [
"Technology",
"Engineering"
] | 5,366 | [
"Cybersecurity engineering",
"Computer law",
"Computing and society",
"Information privacy"
] |
3,006,317 | https://en.wikipedia.org/wiki/Communications%20receiver | A communications receiver is a type of radio receiver used as a component of a radio communication link. This is in contrast to a broadcast receiver which is used to receive radio broadcasts. A communication receiver receives parts of the radio spectrum not used for broadcasting, including amateur, military, aircraft, marine, and other bands. They are often used with a radio transmitter as part of a two-way radio link for shortwave radio or amateur radio communication, although they are also used for shortwave listening.
Features
Commercial communications receivers are characterized by high stability and reliability of performance, and are generally adapted for remote control and monitoring. For marketing purposes, many hobby-type receivers are advertised as "communications receivers" although none are suited for heavy-duty, reliable 24-hour use as the primary form of communication for an isolated station.
Typically, a communications receiver is of the superheterodyne type in double, triple or, more rarely, quad conversion. It features multiple RF and IF amplification stages and may have at least one IF stage that is crystal controlled. It usually has a BFO and a product detector for SSB and CW reception. The frequency coverage of receivers of this type is typically in the range of 500 kHz to 30 MHz. Communication receivers are suited for operation near powerful transmitting facilities and so must have good internal shielding, and effective front-end filtering. They have design features to provide high selectivity and stability. Rejection of unwanted signals (images, intermodulation products) will typically be much greater than a consumer-type general coverage or broadcast receiver.
The front panel controls are typically more comprehensive than those on a broadcasting receiver. Usual features include: signal strength meter; RF gain control; AVC/AGC adjustments; band switching or preselector switching; selectable bandwidth filters or a Q multiplier; BFO tuning; and audio limiters or attenuators. Precise, calibrated, analog tuning and display dials are used, with a separate bandspread control to allow selective tuning of signals close in frequency. In more recent units, electronic digital frequency displays are provided. In communication receivers, the decorative wooden cabinets typical of early broadcast receivers were replaced with utilitarian metal cabinets to provide electromagnetic shielding and mechanical ruggedness.
Communications receivers as an identifiable product type originated in 1933.
The older generation of tube-based communications receivers are affectionately known as boat anchors for their large size and weight. Such receivers include the Collins R-390 and R-390A, the RCA AR-88, the Racal RA-17L and the Marconi Electra. However, even modern solid-state receivers can be very large and heavy, such as the Plessey PR2250, the Redifon R551 or the Rohde & Schwarz EK070/D2-80.
See also
Amateur radio
List of communications receivers
Scanner
Shortwave radio receiver
Shortwave listening
Shortwave radio
Wadley Loop
References
Further reading
Receiver (radio)
Types of radios | Communications receiver | [
"Engineering"
] | 606 | [
"Radio electronics",
"Receiver (radio)"
] |
3,006,333 | https://en.wikipedia.org/wiki/HD%20108874 | HD 108874 is a star with a pair of orbiting exoplanets in the northern constellation of Coma Berenices. It is located 194.5 light years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −30 km/s. The absolute magnitude of this star is 4.79, but at that distance the star has an apparent visual magnitude of 8.76, making it too faint to be visible to the naked eye. HD 108874 has a relatively large proper motion, traversing the celestial sphere at an angular rate of yr−1.
The spectrum of HD 108874 presents as a G-type main-sequence star with a stellar classification of G5 V. (An alternate source gives a class of G9 V.) It is probably billions of years older than the Sun although the age is not well constrained. The level of magnetic activity in the chromosphere is lower than in the Sun and it is spinning with a low rotation period of 40 days. The star has about the same mass as the Sun, but the radius is 6% larger. The abundance of iron, an indicator of the star's metallicity, is 1.18 times that of the Sun. The star is radiating 1.19 times the luminosity of the Sun from its photosphere at an effective temperature of about 5600 K.
Planetary system
In 2003, the jovian planet HD 108874 b was discovered by the US-based team led by Paul Butler, Geoffrey Marcy, Steven Vogt, and Debra Fischer. A total of 20 radial velocity observations, obtained at the W. M. Keck Observatory between 1999 and 2002, were used to make the discovery. In 2005, further observations revealed this star has another jovian planet orbiting further out, designated as HD 108874 c. The orbital parameters of both planets were updated in 2009 with additional observations. There is an additional radial velocity signal in the data at a period of 40 days however this likely caused by the stellar rotation period.
Those two planets are near, and possibly in a 9:2 orbital resonance. This means if HD 108874 b orbits the star nine times, then HD 108874 c orbits twice, because the orbital period for planet c is four and a half times longer than planet b.
See also
List of extrasolar planets
References
External links
Extrasolar Planet Interactions by Rory Barnes & Richard Greenberg, Lunar and Planetary Lab, University of Arizona
G-type main-sequence stars
Planetary systems with two confirmed planets
Coma Berenices
Durchmusterung objects
108874
061028 | HD 108874 | [
"Astronomy"
] | 542 | [
"Coma Berenices",
"Constellations"
] |
3,006,368 | https://en.wikipedia.org/wiki/Net%20interest%20margin | Net interest margin (NIM) is a measure of the difference between the interest income generated by banks or other financial institutions and the amount of interest paid out to their lenders (for example, deposits), relative to the amount of their (interest-earning) assets. It is similar to the gross margin (or gross profit margin) of non-financial companies.
It is usually expressed as a percentage of what the financial institution earns on loans in a time period and other assets minus the interest paid on borrowed funds divided by the average amount of the assets on which it earned income in that time period (the average earning assets).
Net interest margin is similar in concept to net interest spread, but the net interest spread is the nominal average difference between the borrowing and the lending rates, without compensating for the fact that the earning assets and the borrowed funds may be different instruments and differ in volume.
Calculation
NIM is calculated as a percentage of net interest income to average interest-earning assets during a specified period. For example, a bank's average interest-earning assets (which generally includes, loans and investment securities) was $100.00 in a year while it earned interest income of $6.00 and paid interest expense of $3.00. The NIM then is computed as ($6.00 – $3.00) / $100.00 = 3%. Net interest income equals the interest earned on interest-earning assets (such as interest earned on loans and investment securities) minus the interest paid on interest-bearing liabilities (such as interest paid to customers on their deposits).
In particular, for a bank or a financial institution, if the bank or financial institution has a significant amount of non-performing assets (such as loans where full repayment is in doubt), its NIM will generally decrease because interest earned on non-performing assets is treated, for accounting purposes, as repayment of principal and not payment of interest due to the uncertainty that the loan will be fully repaid.
See also
Net interest income
References
Further reading
Successful Bank Asset/Liability Management: A Guide to the Future Beyond Gap, John W. Bitner, Robert A. Goddard, 1992, p. 185.
Interest
Banking
Financial ratios | Net interest margin | [
"Mathematics"
] | 457 | [
"Financial ratios",
"Quantity",
"Metrics"
] |
3,006,440 | https://en.wikipedia.org/wiki/Idaho%20Gem | The mule Idaho Gem (born May 4, 2003) is the first cloned equine and first cloned mule.
He is the result of the collaboration of Dr. Gordon Woods and Dr. Dirk Vanderwall of the Northwest Equine Reproduction Laboratory at the University of Idaho and Dr. Ken White of Utah State University. Two more healthy mule clones were born in succeeding months as a result of Project Idaho, Utah Pioneer on June 9, and Idaho Star on July 27. The project was largely financed by Post Falls, Idaho, businessman Don Jacklin, who also served as president of the American Mule Racing Association. Idaho Gem and Idaho Star were transported to trainers in 2005 to prepare them for racing in 2006. Idaho Gem and Idaho Star both won their first races on June 3, 2006, separate trial races for the Humboldt Futurity during the Winnemucca, Nev., Mule Races, Show and Draft Horse Challenge, June 3 and 4. In the June 4 futurity, Idaho Gem finished third and Idaho Star finished seventh. Idaho Gem won his next race at the San Joaquin Fair in Stockton, June 21. His time of 20.724 seconds over the 350-yard course was the fastest time by a 3-year-old mule through the end of July, the halfway point in the mule racing season. Idaho Gem also collected two seconds in photo finishes with the racing mule Out of My League. The total margin of victory between the two mules in the two races was .043 seconds. Through his first six races, Idaho Gem collected two firsts, two seconds a third and a fourth.
On June 4, 2006, Idaho Gem finished 3rd in the Winnemucca Mule Race. This was the first competition between cloned and natural-born mules.
, Idaho Gem was owned by Jacklin, who was preparing to have him trained for gymkhana events. The mule was reported to be in good health.
See also
List of cloned animals
References
External links
Richard Black, Cloning first for horse family, BBC News, May 29, 2003
2003 animal births
Cloned animals
University of Idaho
Individual mules | Idaho Gem | [
"Biology"
] | 436 | [
"Cloning",
"Cloned animals"
] |
3,006,491 | https://en.wikipedia.org/wiki/Atari%20MMU | Atari MMU is a custom memory management unit chip for the Atari 8-bit computers. It enables access to the hardware registers on ANTIC, GTIA, POKEY and 6520 PIA. The later XL/XE MMU (C061618) also selects OS ROM, Atari BASIC ROM, self-test ROM and LEDs in the 1200XL. On the 128K 130XE the EMMU chip handles similar functionality.
The user cannot directly manipulate the Atari MMU, but selects the various ROMS and memory via the memory-mapped hardware register known as PORTB (5401710 or D30116). Atari changed PORTB from an input port on the 400/800 machines to an output port on the XL/XE machines, leaving two joystick ports instead of four on the XL/XE machines.
By setting and clearing specific bits in PORTB, the user can access either the ROMs or memory locations. No synchronization is required as the OS handles the access.
The bit assignments for PORTB on the XL/XE machines are:
The 1200XL does not have BASIC built-in.
See also
Atari FREDDIE
References
Chadwick, Ian (1985). Mapping the Atari Revised Edition. COMPUTE! Publications, Inc. .
External links
jindroush site(archived) MMU info
INSIGHT: Atari - Compute! Magazine - Talks about Bank Selection in the Atari XL machines.
MMU, Atari | Atari MMU | [
"Technology"
] | 298 | [
"Computing stubs",
"Computer hardware stubs"
] |
3,006,497 | https://en.wikipedia.org/wiki/Social%20rejection | Social rejection occurs when an individual is deliberately excluded from a social relationship or social interaction. The topic includes interpersonal rejection (or peer rejection), romantic rejection, and familial estrangement. A person can be rejected or shunned by individuals or an entire group of people. Furthermore, rejection can be either active by bullying, teasing, or ridiculing, or passive by ignoring a person, or giving the "silent treatment". The experience of being rejected is subjective for the recipient, and it can be perceived when it is not actually present. The word "ostracism" is also commonly used to denote a process of social exclusion (in Ancient Greece, ostracism was a form of temporary banishment following a people's vote).
Although humans are social beings, some level of rejection is an inevitable part of life. Nevertheless, rejection can become a problem when it is prolonged or consistent, when the relationship is important, or when the individual is highly sensitive to rejection. Rejection by an entire group of people can have especially negative effects, particularly when it results in social isolation.
The experience of rejection can lead to a number of adverse psychological consequences such as loneliness, low self-esteem, aggression, and depression. It can also lead to feelings of insecurity and a heightened sensitivity to future rejection.
Need for acceptance
Social rejection may be emotionally painful, due to the social nature of human beings, as well as the essential need for social interaction between other humans. Abraham Maslow and other theorists have suggested that the need for love and belongingness is a fundamental human motivation. According to Maslow, all humans, even introverts, need to be able to give and receive affection to be psychologically healthy.
Psychologists believe that simple contact or social interaction with others is not enough to fulfill this need. Instead, people have a strong motivational drive to form and maintain caring interpersonal relationships. People need both stable relationships and satisfying interactions with the people in those relationships. If either of these two ingredients is missing, people will begin to feel lonely and unhappy. Thus, rejection is a significant threat. In fact, the majority of human anxieties appear to reflect concerns over social exclusion.
Being a member of a group is also important for social identity, which is a key component of the self-concept. Mark Leary of Duke University has suggested that the main purpose of self-esteem is to monitor social relations and detect social rejection. In this view, self-esteem is a sociometer which activates negative emotions when signs of exclusion appear.
Social psychological research confirms the motivational basis of the need for acceptance. Specifically, fear of rejection leads to conformity to peer pressure (sometimes called normative influence, cf. informational influence), and compliance to the demands of others. The need for affiliation and social interaction appears to be particularly strong under stress.
In childhood
Peer rejection has been measured using sociometry and other rating methods. Studies typically show that some children are popular, receiving generally high ratings, many children are in the middle, with moderate ratings, and a minority of children are rejected, showing generally low ratings. One measure of rejection asks children to list peers they like and dislike. Rejected children receive few "like" nominations and many "dislike" nominations. Children classified as neglected receive few nominations of either type.
According to Karen Bierman of Pennsylvania State University, most children who are rejected by their peers display one or more of the following behavior patterns:
Low rates of prosocial behavior, e.g. taking turns, sharing
High rates of aggressive or disruptive behavior
High rates of inattentive, immature, or impulsive behavior
High rates of social anxiety
Bierman states that well-liked children show social savvy and know when and how to join play groups. Children who are at risk for rejection are more likely to barge in disruptively, or hang back without joining at all. Aggressive children who are athletic or have good social skills are likely to be accepted by peers, and they may become ringleaders in the harassment of less skilled children. Minority children, children with disabilities, or children who have unusual characteristics or behavior may face greater risks of rejection. Depending on the norms of the peer group, sometimes even minor differences among children lead to rejection or neglect. Children who are less outgoing or simply prefer solitary play are less likely to be rejected than children who are socially inhibited and show signs of insecurity or anxiety.
Peer rejection, once established, tends to be stable over time, and thus is difficult for a child to overcome. Researchers have found that active rejection is more stable, more harmful, and more likely to persist after a child transfers to another school, than simple neglect. One reason for this is that peer groups establish reputational biases that act as stereotypes and influence subsequent social interaction. Thus, even when rejected and popular children show similar behavior and accomplishments, popular children are treated much more favorably.
Rejected children are likely to have lower self-esteem, and to be at greater risk for internalizing problems like depression. Some rejected children display externalizing behavior and show aggression rather than depression. The research is largely correlational, but there is evidence of reciprocal effects. This means that children with problems are more likely to be rejected, and this rejection then leads to even greater problems for them. Chronic peer rejection may lead to a negative developmental cycle that worsens with time.
Rejected children are more likely to be bullied and to have fewer friends than popular children, but these conditions are not always present. For example, some popular children do not have close friends, whereas some rejected children do. Peer rejection is believed to be less damaging for children with at least one close friend.
An analysis of 15 school shootings between 1995 and 2001 found that peer rejection was present in all but two of the cases (87%). The documented rejection experiences included both acute and chronic rejection and frequently took the form of ostracism, bullying, and romantic rejection. The authors stated that although it is likely that the rejection experiences contributed to the school shootings, other factors were also present, such as depression, poor impulse control, and other psychopathology.
There are programs available for helping children who suffer from social rejection. One large scale review of 79 controlled studies found that social skills training is very effective (r = 0.40 effect size), with a 70% success rate, compared to 30% success in control groups. There was a decline in effectiveness over time, however, with follow-up studies showing a somewhat smaller effect size (r = 0.35).
In the laboratory
Laboratory research has found that even short-term rejection from strangers can have powerful (if temporary) effects on an individual. In several social psychology experiments, people chosen at random to receive messages of social exclusion became more aggressive, more willing to cheat, less willing to help others, and more likely to pursue short-term over long-term goals. Rejection appears to lead very rapidly to self-defeating and antisocial behavior.
Researchers have also investigated how the brain responds to social rejection. One study found that the dorsal anterior cingulate cortex is active when people are experiencing both physical pain and "social pain", in response to social rejection. A subsequent experiment, also using fMRI neuroimaging, found that three regions become active when people are exposed to images depicting rejection themes. These areas are the posterior cingulate cortex, the parahippocampal gyrus, and the dorsal anterior cingulate cortex. Furthermore, individuals who are high in rejection sensitivity (see below) show less activity in the left prefrontal cortex and the right dorsal superior frontal gyrus, which may indicate less ability to regulate emotional responses to rejection.
An experiment performed in 2007 at the University of California at Berkeley found that individuals with a combination of low self-esteem and low attentional control are more likely to exhibit eye-blink startle responses while viewing rejection themed images. These findings indicate that people who feel bad about themselves are especially vulnerable to rejection, but that people can also control and regulate their emotional reactions.
A study at Miami University indicated that individuals who recently experienced social rejection were better than both accepted and control participants in their ability to discriminate between genuine and fake smiles. Though both accepted and control participants were better than chance (they did not differ from each other), rejected participants were much better at this task, nearing 80% accuracy. This study is noteworthy in that it is one of the few cases of a positive or adaptive consequence of social rejection.
Ball toss / cyberball experiments
A common experimental technique is the "ball toss" paradigm, which was developed by Kip Williams and his colleagues at Purdue University. This procedure involves a group of three people tossing a ball back and forth. Unbeknownst to the actual participant, two members of the group are working for the experimenter and following a pre-arranged script. In a typical experiment, half of the subjects will be excluded from the activity after a few tosses and never get the ball again. Only a few minutes of this treatment are sufficient to produce negative emotions in the target, including anger and sadness. This effect occurs regardless of self-esteem and other personality differences.
Gender differences have been found in these experiments. In one study, women showed greater nonverbal engagement whereas men disengaged faster and showed face-saving techniques, such as pretending to be uninterested. The researchers concluded that women seek to regain a sense of belonging whereas men are more interested in regaining self-esteem.
A computerized version of the task known as "cyberball" has also been developed and leads to similar results. Cyberball is a virtual ball toss game where the participant is led to believe they are playing with two other participants sitting at computers elsewhere who can toss the ball to either player. The participant is included in the game for the first few minutes, but then excluded by the other players for the remaining three minutes. A significant advantage of the cyberball software is its openness; Williams made the software available to all researchers. In the software, the researcher can adjust the order of throwing the balls, the user's avatar, the background, the availability of chat, the introductory message and much other information. In addition, researchers can obtain the program's latest version by visiting the official website of CYBERBALL 5.0.
This simple and short time period of ostracism has been found to produce significant increases to self-reported levels of anger and sadness, as well as lowering levels of the four needs. These effects have been found even when the participant is ostracised by out-group members, when the out-group member is identified as a despised person such as someone in the Ku Klux Klan, when they know the source of the ostracism is just a computer, and even when being ostracised means they will be financially rewarded and being included would incur a financial cost. People feel rejected even when they know they are playing only against the computer. A recent set of experiments using cyberball demonstrated that rejection impairs willpower or self-regulation. Specifically, people who are rejected are more likely to eat cookies and less likely to drink an unpleasant tasting beverage that they are told is good for them. These experiments also showed that the negative effects of rejection last longer in individuals who are high in social anxiety.
Life-alone paradigm
Another mainstream research method is the "life alone paradigm", which was first developed by Twenge and other scholars to evoke feelings of rejection by informing subjects of false test results. In contrast to ball toss and cyberball, it focuses on future rejection, i.e. the experience of rejection that participants may potentially experience in the future. Specifically, at the beginning of the experiment, participants complete a personality scale (in the original method, the Eysenck Personality Questionnaire). They are then informed of their results based on their experimental group rather than the real results. Participants in the "rejected" group are told that their test results indicate that they will be alone in the future, regardless of their current state of life. Participants in the "accepted" group will be told they will have a fulfilling relationship. In the control group, participants are told they would encounter some accidents. In this way, the participants' sense of rejection is awakened to take the subsequent measurement. After the experiment, the researcher will explain the results to the participants and apologise.
Scholars point out that this method may cause more harm to the subjects. For example, the participants will likely experience a more severe effect on executive functioning during the test. Therefore, this method faces more significant issue with research ethics and harms than other rejection experiments. Consequently, researchers use this test with caution in experiments and pay attention to the subjects' reactions afterwards.
Psychology of ostracism
Most of the research on the psychology of ostracism has been conducted by the social psychologist Kip Williams. He and his colleagues have devised a model of ostracism which provides a framework to show the complexity in the varieties of ostracism and the processes of its effects. There he theorises that ostracism can potentially be so harmful that humans have evolved an efficient warning system to immediately detect and respond to it.
In the animal kingdom as well as in primitive human societies, ostracism can lead to death due to the lack of protection benefits and access to sufficient food resources from the group. Living apart from the whole of society also means not having a mate, so being able to detect ostracism would be a highly adaptive response to ensure survival and continuation of the genetic line.
Temporal need-threat model
The predominant theoretical model of social rejection is the temporal need-threat model proposed by Williams and his colleagues, in which the process of social exclusion is divided into three stages: reflexive, reflective, and resignation. The reflexive stage happens when social rejection first occurs. It is an immediate effect happened on individuals. Then, the reflective stage enters when the individual starts to reflect and cope with social rejection. Finally, if the rejection last for the long term and the individual cannot successfully cope with it, the social rejection would turn to the resignation stage, where the individual is likely to suffer from severe depression and helplessness.
Reflexive stage
The reflexive stage is the first stage of social rejection and refers to the period immediately after social exclusion has occurred. During this stage, Williams proposed that ostracism uniquely poses a threat to four fundamental human needs; the need to belong, the need for control in social situations, the need to maintain high levels of self-esteem, and the need to have a sense of a meaningful existence. When social rejection is related to the individual's social relationships, the individual's need for belonging and self-esteem is threatened; when it is not associated with it, it is primarily a threat to a sense of control and meaningful existence.
Another challenge that individuals need to face at this stage is the sense of pain. Previous scholars have used neurobiological methods to find that social exclusion, whether intentional or unintentional, evokes pain in individuals. Specifically, neurobiological evidence suggests that social exclusion increases the dorsal anterior cingulate cortex (dACC) activation. This brain region, in turn, is associated with physiological pain in individuals. Notably, the right ventral prefrontal cortex (RVPFC) is also further activated when individuals find that social rejection is intentional; this brain region is associated with the regulation of pain perception, implying that pain perception decreases when individuals understand the source of this social rejection. Further research suggests that personal traits or environmental factors do not affect this pain.
Thus, people are motivated to remove this pain with behaviors aimed at reducing the likelihood of others ostracising them any further and increasing their inclusionary status.
Reflective stage
In the reflective stage, individuals begin to think about and try to cope with social rejection. In the need-threat model, their response is referred to as need fortification, i.e. the creation of interventions that respond to the needs they are threatened by in the reflective stage. Specifically, when individuals' self-esteem and sense of belonging are threatened, they will try to integrate more into the group. As a result, these rejected individuals develop more pro-social behaviors, such as helping others and giving gifts. In contrast, when their sense of control and meaning is threatened, they show more antisocial behavior, such as verbal abuse, fighting, etc., to prove they are essential.
Resignation stage
When individuals have been in social rejection for a long time and cannot improve their situation through effective coping, they move to the third stage, resignation, in which they do not try to change the problem they are facing but choose to accept it. In Zadro's interview study, in which she interviewed 28 respondents in a state of chronic rejection, she found that the respondents were depressed, self-deprecating and helpless. This social rejection can significantly impact the physical and psychological health of the individual.
Controversy
The controversy over temporal need-threat model has focused on whether it enhances or reduces people's perception of pain. DeWall and Baumeister's research suggests that individuals experience a reduction in pain after rejection, a phenomenon they refer to as emotional numbness, which contradicts Williams et al.'s theory that social rejection enhances pain perception. In this regard, Williams suggests that this phenomenon is likely due to differences in the paradigm used in the study, as when using a long-term paradigm such as Life-Alone, individuals do not feel the possibility of rejoining the group, thus creating emotional numbness. This is further supported by Bernstein and Claypool, who found that in separate cyberball and life-alone experiments, stronger stimuli of rejection, such as life-alone, protected people through emotional numbness. In contrast, in the case of minor rejection, such as that in cyberball, the individual's system detects the rejection cue and draws attention to it through a sense of pain.
Popularity resurgence
There has been recent research into the function of popularity on development, specifically how a transition from ostracization to popularity can potentially reverse the deleterious effects of being socially ostracized. While various theories have been put forth regarding what skills or attributes confer an advantage at obtaining popularity, it appears that individuals who were once popular and subsequently experienced a transient ostracization are often able to employ the same skills that led to their initial popularity to bring about a popularity resurgence.
Romantic rejection
In contrast to the study of childhood rejection, which primarily examines rejection by a group of peers, some researchers focus on the phenomenon of a single individual rejecting another in the context of a romantic relationship. In both teenagers and adults, romantic rejection occurs when a person refuses the romantic advances of another, ignores/avoids or is repulsed by someone who is romantically interested in them, or unilaterally ends an existing relationship. The state of unrequited love is a common experience in youth, but mutual love becomes more typical as people get older.
Romantic rejection is a painful, emotional experience that appears to trigger a response in the caudate nucleus of the brain, and associated dopamine and cortisol activity. Subjectively, rejected individuals experience a range of negative emotions, including frustration, intense anger, jealousy, hate, and eventually, despair and possible long-term major depressive disorder. However, there have been cases where individuals go back and forth between depression and anger.
Rejection sensitivity
Karen Horney was the first theorist to discuss the phenomenon of rejection sensitivity. She suggested that it is a component of the neurotic personality, and that it is a tendency to feel deep anxiety and humiliation at the slightest rebuff. Simply being made to wait, for example, could be viewed as a rejection and met with extreme anger and hostility.
Albert Mehrabian developed an early questionnaire measure of rejection sensitivity. Mehrabian suggested that sensitive individuals are reluctant to express opinions, tend to avoid arguments or controversial discussions, are reluctant to make requests or impose on others, are easily hurt by negative feedback from others, and tend to rely too much on familiar others and situations so as to avoid rejection.
A more recent (1996) definition of rejection sensitivity is the tendency to "anxiously expect, readily perceive, and overreact" to social rejection. People differ in their readiness to perceive and react to rejection. The causes of individual differences in rejection sensitivity are not well understood. Because of the association between rejection sensitivity and neuroticism, there is a likely genetic predisposition. Rejection sensitive dysphoria, while not a formal diagnosis, is also a common symptom of attention deficit hyperactivity disorder, estimated to affect a majority of people with ADHD. Others posit that rejection sensitivity stems from early attachment relationships and parental rejection; peer rejection is also thought to play a role. Bullying, an extreme form of peer rejection, is likely connected to later rejection sensitivity. However, there is no conclusive evidence for any of these theories.
Health effects
Social rejection has a large effect on a person's health. Baumeister and Leary originally suggested that an unsatisfied need to belong would inevitably lead to problems in behavior as well as mental and physical health. Corroboration of these assumptions about behavior deficits were seen by John Bowlby in his research. Numerous studies have found that being socially rejected leads to an increase in levels of anxiety. Additionally, the level of depression a person feels as well as the amount they care about their social relationships is directly proportional to the level of rejection they perceive. Rejection affects the emotional health and well being of a person as well. Overall, experiments show that those who have been rejected will suffer from more negative emotions and have fewer positive emotions than those who have been accepted or those who were in neutral or control conditions.
In addition to the emotional response to rejection, there is a large effect on physical health as well. Having poor relationships and being more frequently rejected is predictive of mortality. Also, as long as a decade after a marriage ends, divorced women have higher rates of illness than their non-married or currently married counterparts. In the case of a family estrangement, a core part of the mother's identity may be betrayed by the rejection of an adult child. The chance for reconciliation, however slight, results in an inability to attain closure. The resulting emotional state and societal stigma from the estrangement may harm the psychological and physical health of the parent for the rest of their life.
The immune system tends to be harmed when a person experiences social rejection. This can cause severe problems for those with diseases such as HIV. One study by Cole, Kemeny, and Taylor investigated the differences in the disease progression of HIV-positive gay men who were sensitive to rejection compared to those who were not considered rejection sensitive. The study, which took place over nine years, indicated significantly faster rates of low T helper cells, therefore leading to an earlier AIDS diagnosis. They also found that those patients who were more sensitive to rejection died from the disease an average of two years earlier than their non-rejection sensitive counterparts.
Other aspects of health are also affected by rejection. Both systolic and diastolic blood pressure increase upon imagining a rejection scenario. Those who are socially rejected have an increased likelihood of suffering from tuberculosis, as well as suicide. Rejection and isolation were found to affect levels of pain following an operation as well as other physical forms of pain. MacDonald and Leary theorize that rejection and exclusion cause physical pain because that pain is a warning sign to support human survival. As humans developed into social creatures, social interactions and relationships became necessary for survival, and the physical pain systems already existed within the human body.
In fiction, film and art
Artistic depictions of rejection occur in a variety of art forms. One genre of film that most frequently depicts rejection is romantic comedies. In the film He's Just Not That Into You, the main characters deal with the challenges of reading and misreading human behavior. This presents a fear of rejection in romantic relationships as reflected in this quote by the character Mary, "And now you have to go around checking all these different portals just to get rejected by seven different technologies. It's exhausting."
Social rejection is also depicted in theatrical plays and musicals. For example, the film Hairspray shares the story of Tracy Turnblad, an overweight 15-year-old dancer set in the 1960s. Tracy and her mother are faced with overcoming society's expectations regarding weight and physical appearances.
See also
Closure (sociology)
Labelling
Marginalization
Outcast
Parental alienation
Rejection hotline
Social defeat
Social stigma
Sociometry
References
Further reading
Asher, S. R., & Coie, J. D. (1990). Peer rejection in childhood. Cambridge University Press.
Bierman, K. L. (2003). Peer rejection: Developmental processes and intervention strategies. New York: The Guilford Press.
Leary, M. (2001). Interpersonal rejection. New York, NY: Oxford University Press.
Savage, E. (2002). Don't take it personally: The art of dealing with rejection. Oakland, CA: New Harbinger Publications.
Williams, K. D., Forgás, J. P., & von Hippel, W. (2005). The social outcast: Ostracism, social exclusion, rejection, and bullying. New York: Psychology Press.
External links
CBS news story on rejection and the brain
Ostracism Laboratory
Psychology Today article on self-esteem and social rejection
Self, Emotion, and Behavior Lab
Social Relations Laboratory
Shunning
Human development
Interpersonal relationships
Group processes | Social rejection | [
"Biology"
] | 5,238 | [
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"Human development",
"Behavioural sciences",
"Interpersonal relationships",
"Human behavior"
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3,007,056 | https://en.wikipedia.org/wiki/Corsair%20Gaming | Corsair Gaming, Inc. (stylized as CORSAIR) is an American computer peripherals and gaming brand headquartered in Milpitas, California. Previously known as Corsair Components and Corsair Memory, it was incorporated in California in January 1994 originally as Corsair Microsystems and reincorporated in Delaware in 2007. The company designs and sells a range of computer products, including high-speed DRAM modules, power supplies (PSUs), USB flash drives, CPU/GPU and case cooling, gaming peripherals (such as keyboards and computer mice), computer cases, solid-state drives (SSDs), and speakers.
It leases a production facility in Taoyuan City, Taiwan, for assembly, testing and packaging of select products, with distribution centers in North America, Europe, and Asia and sales and marketing offices in major markets worldwide. It trades under the ticker symbol CRSR on the NASDAQ stock exchange. Lockdown orders associated with the COVID-19 pandemic, and a rise in demand for computing equipment, including the computer gaming sector, led to a significant short-term increase in Corsair's revenue.
History
The company was founded as Corsair Microsystems Inc. in 1994 by Andy Paul, Don Lieberman, and John Beekley. Corsair originally developed level 2 cache modules, called cache on a stick (COASt) modules, for OEMs. After Intel incorporated the L2 cache in the processor with the release of its Pentium Pro processor family, Corsair changed its focus to DRAM modules, primarily in the server market. This effort was led by Richard Hashim, one of the early employees at Corsair. In 2002, Corsair began shipping DRAM modules that were designed to appeal to computer enthusiasts, who were using them for overclocking. Since then, Corsair has continued to produce memory modules for PCs, and has added other PC components as well.
Corsair expanded its DRAM memory module production into the high end market for overclocking. This expansion allows for high power platforms and the ability to get more performance out of the CPU and RAM. The Corsair Vengeance Pro series and Corsair Dominator Platinum series are built for overclocking applications.
Corsair has since expanded their product line to include many types of high-end gaming peripherals, high performance air and water cooling solutions, and other enthusiast-grade components. Around 2009, Corsair contacted CoolIT Systems to integrate their liquid cooling technology into Corsair's offerings which resulted in a long-term partnership.
In May 2021, Corsair announced that it will relocate its headquarters from Fremont to Milpitas, with the new lease stated to take effect in March 2022. In August 2024, Corsair laid off 90 employees.
Acquisitions
On July 26, 2017, EagleTree Capital entered into an agreement to acquire a majority stake in Corsair from Francisco Partners and several other minority shareholders in a deal valued at $525 million. Corsair Founder and CEO Andy Paul retains his equity stake and remains in his role as CEO.
On June 27, 2018, Corsair announced that it will be acquiring Elgato Gaming from the Munich-based company Elgato Systems. The company retained their Eve home automation division and was subsequently renamed to Eve Systems.
On July 24, 2019, it was announced that Corsair had acquired custom PC builder Origin PC. In February 2024, Corsair announced it would be moving Origin PC's manufacturing operations to Atlanta and closing its facility in Miami. As a result, 55 employees were laid off.
On December 16, 2019, Corsair announced its acquisition of game controller manufacturer SCUF Gaming.
On August 21, 2020, Corsair filed registration documents with the U.S. Securities and Exchange Commission for a planned $100 million IPO.
On July 17, 2023, Corsair announced that it had acquired the online mechanical keyboard retailer Drop (formerly known as Massdrop).
On September 16, 2024, Corsair announced that it was set to acquire the Fanatec product line from Endor AG, which completed on September 23.
Products
Computer components:
DRAM modules
ATX and SFX PSUs
Computer cases
Liquid CPU and GPU cooling solutions
Computer fans
Solid-state drives
Capture cards (Elgato)
Pre-built high end gaming PCs (Origin PC)
Voyager laptop
Periphery devices:
USB flash drives
Audio headsets for gaming
Headset stands
Gaming monitors
Webcams and streaming cameras
Gaming keyboards
Computer mice
Mousepads
Gaming chairs
Microphones
Sim racing wheels
Since the custom computer industry has experienced an increased interest in products with RGB lighting, Corsair has added this feature to almost all of their product lines. In the gaming industry, Corsair has its biggest share of the market in memory modules (around 44%) and gaming keyboards (around 14%).
See also
List of computer hardware manufacturers
External links
References
1994 establishments in California
2020 initial public offerings
Companies based in Milpitas, California
Companies listed on the Nasdaq
Computer companies established in 1994
Computer companies of the United States
Computer enclosure companies
Computer hardware companies
Computer hardware cooling
Computer memory companies
Computer peripheral companies
Computer power supply unit manufacturers
Impact of the COVID-19 pandemic on the video game industry
Technology companies based in the San Francisco Bay Area
Video game hardware | Corsair Gaming | [
"Technology"
] | 1,105 | [
"Computer hardware companies",
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3,007,087 | https://en.wikipedia.org/wiki/Cacodyl%20oxide | Cacodyl oxide is a chemical compound of the formula [(CH3)2As]2O. This organoarsenic compound is primarily of historical significance since it is sometimes considered to be the first organometallic compound synthesized in relatively pure form.
"Cadet's fuming liquid", which is composed of cacodyl and cacodyl oxide, was originally synthesized by heating potassium acetate with arsenic trioxide. It has a disagreeable odor and is toxic.
The molecular structure of [Ph2As]2O (Ph = phenyl), the tetraphenyl analogue of cacodyl oxide, has been established by X-ray crystallography.
See also
Arsenic
Arsine
Cacodylic acid
Lewisite
Cacodyl cyanide
References
Cacodyl compounds
Foul-smelling chemicals | Cacodyl oxide | [
"Chemistry"
] | 176 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
3,007,111 | https://en.wikipedia.org/wiki/Map-coloring%20games | Several map-coloring games are studied in combinatorial game theory. The general idea is that we are given a map with regions drawn in but with not all the regions colored. Two players, Left and Right, take turns coloring in one uncolored region per turn, subject to various constraints, as in the map-coloring problem. The move constraints and the winning condition are features of the particular game.
Some players find it easier to color vertices of the dual graph, as in the Four color theorem. In this method of play, the regions are represented by small circles, and the circles for neighboring regions are linked by line segments or curves. The advantages of this method are that only a small area need be marked on a turn, and that the representation usually takes up less space on the paper or screen. The first advantage is less important when playing with a computer interface instead of pencil and paper. It is also possible to play with Go stones or Checkers.
Move constraints
An inherent constraint in each game is the set of colors available to the players in coloring regions. If Left and Right have the same colors available to them, the game is impartial; otherwise the game is partisan. The set of colors could also depend on the state of the game; for instance it could be required that the color used be different from the color used on the previous move.
The map-based constraints on a move are usually based on the region to be colored and its neighbors, whereas in the map-coloring problem, regions are considered to be neighbors when they meet along a boundary longer than a single point. The classical map-coloring problem requires that no two neighboring regions be given the same color. The classical move constraint enforces this by prohibiting coloring a region with the same color as one of its neighbor. The anticlassical constraint prohibits coloring a region with a color that differs from the color of one of its neighbors.
Another kind of constraint is entailment, in which each move after the first must color a neighbor of the region colored on the previous move. Anti-entailment is another possible constraint.
Other sorts of constraints are possible, such as requiring regions that are neighbors of neighbors to use different or identical colors. This concept can be considered as applying to regions at graph distance two, and can be generalized to greater distances.
Winning conditions
The winner is usually the last player to move. This is called the normal play convention. The misère play convention considers the last player to move to lose the game. There are other possible winning and losing conditions possible, such as counting territory, as in Go.
Monochrome and variants
These games, which appeared in (Silverman, 1971), all use the classical move constraint. In the impartial game "Monochrome" there is only one color available, so every move removes the colored region and its neighbors from play. In "Bichrome" both players have a choice of two colors, subject to the classical condition. Both players choose from the same two colors, so the game is impartial. "Trichrome" extends this to three colors to the players. The condition can be extended to any fixed number of colors, yielding further games. As Silverman mentions, although the Four color theorem shows that any planar map can be colored with four colors, it does not apply to maps in which some of the colors have been filled in, so adding more than four colors may have an effect on the games.
Col and Snort
In "Col" there are two colors subject to the classical constraint, but Left is only allowed to color regions B"l"ue, while Right is only allowed to color them "R"ed. Thus this is a partisan game, because different moves become available to Left and Right in the course of play.
"Snort" uses a similar partisan assignment of two colors, but with the anticlassical constraint: neighboring regions are not allowed to be given different colors. Coloring the regions is explained as assigning fields to bulls and cows, where neighboring fields may not contain cattle of the opposite sex, lest they be distracted from their grazing.
These games were presented and analyzed in (Conway, 1976). The names are mnemonic for the difference in constraints (classical map coloring versus animal noises), but Conway also attributes them to his colleagues Colin Vout and Simon Norton.
Other games
The impartial game "Contact" (Silverman, 1971) uses a single color with the entailment constraint: all moves after the first color a neighbor of the most recently colored region. Silverman also provides an example of "Misère Contact".
The concept of a map-coloring game may be extended to cover games such as Angels and Devils, where the rules for coloring are somewhat different in flavor.
References
Revised and reprinted as
Revised and reprinted as
Combinatorial game theory
Mathematical games | Map-coloring games | [
"Mathematics"
] | 982 | [
"Mathematical games",
"Recreational mathematics",
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"Game theory",
"Combinatorial game theory"
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3,007,126 | https://en.wikipedia.org/wiki/Benzyl%20butyl%20phthalate | Benzyl butyl phthalate (BBP) is an organic compound historically used a plasticizer, but which has now been largely phased out due to health concerns. It is a phthalate ester of containing benzyl alcohol, and n-butanol tail groups. Like most phthalates, BBP is non-volatile and remains liquid over a wide range of temperatures. It was mostly used as a plasticizer for PVC, but was also a common plasticizer for PVCA and PVB.
BBP was commonly used as a plasticizer for vinyl foams, which are often used as sheet vinyl flooring and tiles. Compared to other phthalates it was less volatile than dibutyl phthalate and imparted better low temperature flexibility than di(2-ethylhexyl) phthalate.
BBP is classified as toxic by the European Chemical Bureau (ECB) and hence its use in Europe has declined rapidly.
Structure and reactivity
BBP is a diester. Since BBP contains two ester bonds it can react in a variety of chemical pathways. Both the carbonyl C-atoms are weakly electrophilic and therefore targets for attacks by strong nucleophilic compounds. Besides the carbonyl C-atom target, it contains a C-H bond whereas the H-atom is weakly acidic, which makes it susceptible for deprotonation by a strong base. BBP is hydrolyzed under either acidic or basic conditions. The hydrolysis under acidic conditions is a reversion of the Fischer-Speier esterification, whereas the hydrolysis under basic conditions is performed by saponification. Since BBP contains two ester bonds it is difficult to perform a chemoselective reaction.
Under basic conditions BBP can undergo saponification. The saponification number of BBP is 360 mg KOH/g. The amount of carboxylic functional groups per molecule are relatively high (2 carboxylic functional groups with a molecular weight of 312.36). This makes the compound relatively unsaponifiable.
Synthesis
Concentrated sulfuric acid dehydrates n-butyl alcohol to yield 1-butene, which reacts with phthalic anhydride to produce n-butyl phthalate. Phthalic anhydride does react directly with 1-butanol to form this same intermediate, but further reaction to form dibutyl phthalate does occur to a significant extent. Carrying out the procedure using 1-butene avoids this side reaction. Monobutyl phthalate is isolated and then added to a mixture of benzyl bromide in acetone in the presence of potassium carbonate (to keep the pH high to facilitate the substitution reaction required to form the second ester linkage), from which BBP can then be isolated.
Metabolism
BBP can be absorbed by the human body in a variety of ways. First of all, it can be taken up dermally, meaning that the compound is absorbed by the skin. Studies in rats show that 27% of the uptake of BBP occurs via this route. During this process, the structure of the phthalate diester determines the degree of dermal absorption.
BBP can also be taken up orally. The amount of the compound that is being absorbed by the body depends on the dose that has been administered. Absorption seems to be limited at high doses, meaning that small amounts are taken up more easily than great amounts. Finally, BBP can be inhaled. In this case, BBP is absorbed via the lungs.
BBP is biotransformed in the human body in numerous of ways. Gut esterases metabolize BBP to monoester metabolites. Those are mainly monobutyl and mono-benzyl phthalate (MBzP) plus small amounts of mono-n-butyl phthalate. The ratio of monobutyl to monobenzyl phthalate has been determined to be 5:3. These metabolites can be absorbed and excreted directly or undergo a phase II reaction. In the latter, they are conjugated with glucuronic acid and then excreted as glucuronate. Studies in rats have shown that 70% of BBP is not conjugated while 30% is conjugated. At high concentrations of BBP, relatively less metabolite is conjugated. This indicates that the conjugation pathway (glucuronidation) is saturated at high amounts of administered BBP. The metabolites of BBP are excreted rapidly, 90% of them has left the body within 24 hours. As a consequence, the half-life of BBP in the blood is quite low and counts up to only 10 minutes. However, monoester metabolites of BBP (such as monophthalate) have a longer half-life of 6 hours.
BBP is metabolized quite efficiently within the body. While a major part of the BBP is excreted as a mono-benzyl phthalate metabolite, a minor fragment of the BBP is excreted in the form of mono-butyl phthalate. BBP is rarely found in the bile in its original form. Nevertheless, metabolites like monobutyl glucuronide and monobenzyl phthalate glucuronide as well as trace amounts of free monoesters can be found there.
Mode of action
Relatively little is known about the modes of action of BBP. Experimental research does hint at a number of mechanisms, though. One phenomenon is that BBP binds to the estrogen receptor of rats. In vitro-experiments do show a weak potential of BBP to have an influence on estrogen-mediated gene expression. This is because phthalates like BBP are mimicking estrogens. Metabolites of BBP, on the other hand, are only weakly reactive with the estrogen receptor. Not much is known about if and how this mechanism plays out in vivo.
Furthermore, BBP binds to intracellular steroid receptors and causes genomic effects by doing so. BBP also interferes with ion-channel receptors which cause non-genomic effects. The underlying mechanism is that BBP blocks the calcium signaling that is coupled with P2X receptors. Calcium signaling, mediated via P2X, eventually has an influence in cell proliferation and bone remodeling. During developmental phases of bone remodelling, high environmental exposure of BBP might therefore pose a problem.
Exposure
The exposure of the general population to BBP has been estimated by several authorities. One of the authorities, the International Program on Chemical Safety (IPCS), came to the conclusion that exposure to BBP is mainly caused by food intake. BBP, as many other phthalates, is used to increase the flexibility of plastics. However, phthalates are not bound to the plastics which means that they can easily be released into the environment. From there it can be taken up into food during crop cultivation. Alternatively, BBP can enter food via food packaging materials. Moreover, children may be exposed to BBP by mouthing of toys. Various studies by authorities, between the 1980s and 2000s, have been done to estimate the general population exposure to BBP in different countries with varying results. The adult exposure was estimated to be 2 μg/kg body weight/day in the U.S. BBP exposure to children is likely to be higher due to differences in food intake.
Nonetheless, these estimates should be interpreted with caution as they are based on different food types, different assumptions were used in calculations, levels of BBP in food vary in different countries and levels of BBP in food changes over time.
Next to general exposure there is also occupation-related exposure to BBP . This can occur via inhalation of vapors or via skin contact. This has been estimated to be 286 μg/kg body weight/day. However, in general the occupational exposure is thought be lower than this. The NOAEL of BBP was experimentally found to be 50 mg/kg body weight/day and the associated margin of safety is ca. 4,800 or more. Thus, BBP does not seem to pose a very high risk under conditions of general or occupational exposure based on current estimates.
Toxicity and adverse effects
No primary irritation or sensitization reactions were found in a patch test involving 200 volunteers. However, if BBP is taken up by the body it can exert toxic effects. It has a LD50 for rats ranging from 2 to 20 g/kg body weight.
Occupational hazards
Workers in the PVC processing industry are exposed to higher levels of BBP than the general public and are thus more at risk of experiencing negative health effects. No effects of the respiratory or peripheral nerve system have been observed in workers. Although slightly higher levels of BBP metabolites were found in their urine. Long-term occupational exposure to BBP does, however, significantly increase the risk of multiple myeloma.
Children
Children are possibly exposed to higher levels of BBP than adults. Since children form a vulnerable group for chemical exposure, studies have been conducted to evaluate the effects of BBP exposure. PVC flooring has been linked to a significant increase in the risk of bronchial obstruction in the first two years of life and in the development of language delay in pre-school aged children. BBP has also been positively associated with airway inflammation in children living in urban areas. Moreover, there is evidence suggesting that prenatal exposure to BBP coming from in house dust affects the risk of childhood eczema. The exact mechanism of how phthalates and their metabolites reach the fetus remain unclear. However, since these chemicals seem to be able to reach the fetus they are thought to affect fetal health and development. Further research is needed to establish the effect of prenatal exposure on fetal development.
Teratogenicity and reproductive effects
Only a few studies have been done on reproductive effects of BBP on humans, but the results are inconclusive. According to the NTP-CERHR the adverse reproductive effects are negligible for exposed men. Yet, one study found a link between altered semen quality and exposure to monobutyl phthalate, a major metabolite of BBP. No research has been done on the teratogenic effects of BBP on humans. However, numerous studies have been conducted with animals. Prenatal exposure to high levels of BBP in rats can lead to lower fetal body weight, increased incidence of fetal malformations, post-implantation loss and even embryonic death. The precise teratogenic effects observed in rat fetuses seem to be related to the period of exposure in development. Exposure to BBP in the first half of pregnancy lead to embryolethality while exposure in the second half to teratogenicity.
In a two-generational study male offspring were found to have macroscopic and microscopic changes in the testes, decreased serum testosterone concentrations in addition to reduced sperm production. Additionally, reduced seminal vesicle weight has been observed. These results indicate a clear negative effect on the fertility.
Other toxicity studies in animals
Numerous studies have been carried out in animals to elucidate the adverse effects of BBP exposure. Long-term BBP exposure in rats leads to reduced body weight, increased weight of the liver and kidneys and carcinogenicity. In male rats the incidence of pancreatic tumors increased while in female rats the incidence for both pancreatic and bladder tumors increased.
Although BBP has been linked to carcinogenicity, studies indicate that BBP is not genotoxic.
Environmental toxicology
BBP, like other low molecular weight phthalate esters, is toxic to aquatic organisms. This includes unicellular freshwater green algae such as Selenastrum capricornutum. BBP has also been shown to be toxic to freshwater invertebrates like D. magna. For these organisms, the toxic effect correlates with the water solubility of the phthalate which is relatively high for BBP compared to high molecular weight phthalates. BBP affects saltwater invertebrates significantly. Experiments with mysid shrimp show that BBP is acutely toxic to these organisms. Among the species of fish, the sweetwater fish bluegills were shown to be toxically affected by BBP. Furthermore, a rapid lethal effect has been observed for the saltwater fish Parophrys vetulus.
Degradation
When the degradation of BBP is taken into consideration, one should be aware of the fact that it contains two ester functional groups. This gives organisms a handle for biotransformations. The ester groups gives BBP hydrophilic properties and will therefore hydrolyze fairly easy. Following an examination performed in 1997, it was found that biotransformations play a very important role in the degeneration of BBP. Furthermore, the solubility in water plays a significant role in the effectiveness of biotransformation in an environment. The butyl group gives BBP a slightly more hydrophobic property, compared to other plasticizer it is relatively good soluble. The longer the alkyl chain the less soluble and the less well it is degenerated.
Legislation measures
BBP was listed as a developmental toxicant under California's Proposition 65 on December 2, 2005. California's Office of Environmental Health Hazard Assessment (OEHHA), on July 1, 2013, approved a Maximum Allowable Dose Level of 1,200 micrograms per day for BBP. Canadian Authorities have restricted the usage of phthalates, including BBP, in soft vinyl children's toys and child care articles.
According to EU Council Directive 67/548/EEC1, BBP is classified as reproductive toxicant and therefore restricted in use. The restriction covers the placing on the market and use in any type of toys and childcare articles. These restrictions are in place since 16 January 2017. Due to the classification and labelling of BBP companies have moved to the use of alternatives. Restrictions are not limited to toys. Since 22 November 2006 cosmetic products containing BBP shall not be supplied to consumers in the EU.
References
External links
C-307 An Act respecting bis(2-ethylhexyl)phthalate, benzyl butyl phthalate and dibutyl phthalate
Datasheet
Plasticizers
Phthalate esters
Endocrine disruptors
Benzyl esters
Butyl esters | Benzyl butyl phthalate | [
"Chemistry"
] | 3,003 | [
"Endocrine disruptors"
] |
3,007,169 | https://en.wikipedia.org/wiki/Lasso%20of%20Truth | The Lasso of Truth is a weapon wielded by DC Comics superhero Wonder Woman, Princess Diana of Themyscira. It is also known as the Lariat of Truth, the Magic Lasso, the Lasso of Hestia or the Golden Perfect. It was created by William Moulton Marston, inventor of the lie detector, as an allegory for feminine charm, but it later became more popular as a device to extract truth from people.
The lariat forces anyone it captures into submission; compelling its captives to obey the wielder of the lasso and tell the truth.
Origin and influences
William Moulton Marston created Wonder Woman but he also worked, in the period before, during and after World War I, on understanding and perfecting the systolic blood-pressure test while working on his Ph.D. in psychology at Harvard University. Blood pressure was one of several elements measured in the polygraph tests that were being perfected since as far back as Italian criminologist Cesare Lombroso, in 1895. Marston's wife, psychologist and lawyer Elizabeth Holloway Marston, one of his inspirations for the Wonder Woman character, also played a key role in his lie detector research.
The lie detector had nothing to do with Marston's creation of the Magic Lasso. Wonder Woman's Magic Lasso or Golden Lasso was the direct result of their research into emotions and was more about submission than truth. Marston created the Magic Lasso as an allegory for feminine charm and the compliant effect it has on people. The idea behind feminine allure was that submission to a pleasant controller (instead of a harsh one) was more pleasant and therefore made it more likely that people would submit.
In a 1997 academic article, psychologist Geoffry Bunn incorrectly reinforces a correlation between the lasso and the systolic blood-pressure test:
Publication history
Pre-Crisis
The lasso was formed from Aphrodite's girdle, which made it indestructible, and its magical properties were granted by the Goddess herself. The powers forced whoever was bound within it to obey the commands of whoever held the other end. This effect could be used on larger groups of people, although this reduced its efficiency. In addition to being unbreakable, the lasso was also infinitely elastic.
Diana coated it in special Amazon chemicals that allowed it to transform her civilian clothes into Wonder Woman's garb. Diana demonstrated a remarkable level of skill with the lasso, performing such feats as twirling it to create air currents (upon which she could float) and spinning it to emit magic-disrupting frequencies.
Post-Crisis
In post-Crisis, continuity, the Lasso was forged by the god Hephaestus from the Golden Girdle of Gaea once worn by Antiope, sister of Hippolyta. It is so strong that not even Hercules can break it. It is given to Diana after Hippolyta consults the Goddesses. Originally the lasso was given to Wonder Woman when she returned to Paradise Island. William Moulton Marston later retconned the origin story in Wonder Woman #1 (June 1942), in which it is shown that her mother gave it to her after Diana won a tournament on Paradise Island, before she left the island for the United States.
Empowered by the fires of Hestia, the lasso forces anyone held by it to tell the absolute truth. Furthermore, simple physical contact with the lasso can be enough to have this effect such as when Barbara Ann Minerva attempted to swindle it from Diana, but was forced to confess her intentions when she held the lasso. It is also infinitely long, and can lengthen depending on its user's desire. The fires are said to even be able to cure insanity, as they did in the case of Ares, God of War, when he attempted to incite World War III. He renounced his plan when the lasso showed him that such a war would not only destroy all life on Earth as he wished, but also any potential worshippers he sought to gain from it. The lasso possesses incredible strength and is virtually unbreakable. One story even showed Wonder Woman using the lasso to contain the explosion of two atom bombs. Unable to stop the American bombs that would set off a Russian doomsday machine she wrapped the bombs in her lasso and let the bombs explode. It has easily held beings with tremendous superhuman strength such as Superman, Captain Marvel, who has the strength of Hercules and the Power of Zeus, and Power Girl, as well as gods such as Ares and Heracles. In several Pre-Crisis stories, it was even capable of binding Wonder Woman herself on the occasions she was caught, sometimes by Gunther. It is shown that Wonder Woman still has her powers even if bound by the lasso.
The only times it has ever been shown to break was when truth itself was challenged. For example, in JLA the lasso broke when she refused to believe the confession it wrought from Rama Khan. Elsewhere, when the backwards-thinking monster Bizarro was caught in Trinity, he was horrified by the idea of truth. As the antithesis of reason and logic, he was able to break the lasso. The fairy tale villainess, Queen of Fables, who has the power to bring any fictional or non-true character to life, and is herself "fictional", had power over the lasso by bringing fictional characters to life and having her minions break it.
The magic lasso has subsequently been shown to produce a wide array of effects. When battling the entity Decay, Wonder Woman used the lasso's link to Gaia, the goddess of the earth, as a circuit between the earth and the monster, pumping the entity of death with life-giving energies that destroyed the creature. Diana herself stated that the lasso's connection to Gaea also constantly renews its user with these energies. Wonder Woman has also used it to create a ring of protective fire around people to protect them from Circe's bestiamorphs. The lasso's energies are also shown to be capable of destroying beings forcibly resurrected by the rings of the Black Lantern Corps. As the goddess of truth, Diana also used it to take memories of Donna Troy and restore her to life. In Pre-Crisis comics, the lasso also had the power to effectively control those who were bound within it.
In the mini-comic enclosed with the release of the Kenner Super Powers figure of Wonder Woman, the Amazing Amazon ensnares a mind-controlled Superman with her lasso, preventing him from destroying the Washington Monument. Superman is unable to resist the powers of the lasso as Wonder Woman renders him unconscious. Later, Wonder Woman uses her lasso on Brainiac and commands the villain to release Superman from his mind control.
In later Post-Crisis comics, the power of truth was written as innate to Wonder Woman herself, with the lasso merely a focus of that power. A storyline in the Morrison-era JLA comics by Joe Kelly depicted the lasso as an archetypal manifestation of universal truth, and, once broken (like when Wonder Woman doubted the truth that it was revealing to her because she didn't like it), disrupted the underlying truth of reality itself. With the lasso broken, reality came to be dictated by whatever people believed to be the case, starting with older beliefs and extending to beliefs that were held by various individuals in the present. This resulted in Earth becoming the center of the universe for two weeks, Earth becoming flat for several hours, the moon turning into cheese for a time, Kyle Rayner assuming a Hal Jordan-like appearance (many people still saw Hal as 'the' Green Lantern), and Batman fading in and out of existence due to his 'urban legend' status (meaning that people weren't sure if he even existed). This allegorical interpretation is often ignored in later stories and by much of fandom, as the lasso was long established as magically unable to break, and was never before stated to be the ultimate representation of truth. During her adventures with the Justice League team of superheroes Diana eventually battled a villain named Amazo who was able to duplicate aspects of the lasso for his own use.
During her tenure as writer for Wonder Woman, Gail Simone has further explored the nature of the Lasso of Truth, describing it as "a deadly weapon, that not only binds you, and follows its mistress' commands, the damned thing can see into your soul".
This lasso should not be confused with the lasso of the current Wonder Girl, Cassie Sandsmark. That lasso, given to her by Ares, has the power to shock a target with Zeus' lightning if Cassandra ropes her target and becomes angry with them. Donna Troy also wields a mystical lasso of her own called the Lasso of Persuasion, which has the ability to persuade anyone within its confines to do Donna's bidding if her willpower is greater than theirs.
Similarly, the character Bizarra also has a magic lasso, the difference being that her lasso forces one to tell lies.
Despite Wonder Woman's lasso being mystical in origin, in Bruce Wayne: The Road Home, Batman apparently has reverse-engineered the Amazo technology, which aids duplicating the lasso's capabilities artificially. During Endgame, when the Joker uses a toxin to turn the Justice League against Batman, Batman is able to immobilise Diana using the 'bind of veils', essentially a Lasso of Lies that was woven by Hephaestus after he created the original Lasso by inverting the original weave. Allegedly created using the wool from the sheep used by Odysseus and his men to escape the blind cyclops, it took Batman two years to acquire on the supernatural black market, incorporating it into a suit of armor specifically designed to stand up to the Justice League, with the bind of veils trapping Diana in an illusion where she has killed Batman.
In the Elseworlds tale Red Son, Wonder Woman was subdued and restrained in her own lasso by the Soviet terrorist incarnation of Batman. In order to free herself and rescue Superman from Lex Luthor's deadly red sun lamps, Wonder Woman snapped the cords of her "indestructible" lasso. The shock of the incident appeared to age Diana, leaving her grey-haired, frail, and unable to speak.
In other media
Film
The Lasso of Truth appears in Wonder Woman (2009).
The Lasso of Truth appears in films set in the DC Animated Movie Universe (DCAMU).
The Lasso of Truth appears in films set in the DC Extended Universe (DCEU).
The Lasso of Truth appears in Teen Titans Go! To the Movies.
The Lasso of Truth appears in Superman: Red Son. This version is connected to Wonder Woman's life force, and she uses it as the main source of her powers and longevity.
The Lasso of Truth appears in Space Jam: A New Legacy.
In television
The Lasso of Truth appears in Wonder Woman (1975). This version can cause selective amnesia.
The Lasso of Truth appears in Super Friends. This version can follow Wonder Woman's commands, physically moving on its own to accomplish tasks.
The Lasso of Truth appears in the DC Animated Universe series Justice League and Justice League Unlimited.
The Lasso of Truth appears in Justice League Action.
The Lasso of Truth appears in DC Super Hero Girls.
Video games
The Lasso of Truth appears in Justice League Heroes.
The Lasso of Truth appears in Mortal Kombat vs. DC Universe.
The Lasso of Truth appears in DC Universe Online.
The Lasso of Truth appears in Injustice: Gods Among Us.
The Lasso of Truth appears in Infinite Crisis.
The Lasso of Truth appears as part of the Wonder Woman skin in Fortnite.
The Lasso of Truth appears in Justice League: Cosmic Chaos.
The Lasso of Truth appears in MultiVersus.
Footnotes
References
Brown, Matthew J. / "Love Slaves and Wonder Women":/ "Radical Feminism and Social Reform in the Psychology of William Moulton Marston", (Uncopyrighted scholarly report) (2016): pp 1–39.
Bunn, Geoffrey C. "The Lie Detector, Wonder Woman and Liberty:The Life and Works of William Moulton Marston", History of the Human Sciences, 10 (1997): pp 91–119.
Jett, Brett. "Who Is Wonder Woman?", (Manuscript) (2009): pp 1–101.
Jett, Brett. "Who Is WW?: Magic Lasso", (Article) (2015).
Lamb, Marguerite. "Who Was Wonder Woman? Long-ago LAW alumna Elizabeth Marston was the muse who gave us a superheroine". Boston University Alumni Magazine, Fall 2001.
Lepore, Jill. The Secret History of Wonder Woman, New York: Alfred A. Knopf, 2014,
Moore, Mark Harrison. The Polygraph and Lie Detection. Committee to Review the Scientific Evidence on the Polygraph (National Research Council (U.S.)), 2003.
Richard, Olive. "Our Women Are Our Future" (Article), Family Circle, 14 August 1942.
Valcour, Francinne. Manipulating the Messenger: Wonder Woman as an American Female Icon (Dissertation) (2006): 1–372.
Characters created by H. G. Peter
Characters created by William Moulton Marston
DC Comics objects
Fantasy weapons
Fictional elements introduced in 1942
Fictional weapons
Lie detection
Magic items
Ropes
Wonder Woman | Lasso of Truth | [
"Physics"
] | 2,808 | [
"Magic items",
"Physical objects",
"Matter"
] |
3,007,213 | https://en.wikipedia.org/wiki/Electric%20discharge | In electromagnetism, an electric discharge is the release and transmission of electricity in an applied electric field through a medium such as a gas (i.e., an outgoing flow of electric current through a non-metal medium).
Applications
The properties and effects of electric discharges are useful over a wide range of magnitudes. Tiny pulses of current are used to detect ionizing radiation in a Geiger–Müller tube. A low steady current can illustrate the gas spectrum in a gas-filled tube. A neon lamp is an example of a gas-discharge lamp, useful both for illumination and as a voltage regulator. A flashtube generates a short pulse of intense light useful for photography by sending a heavy current through a gas arc discharge. Corona discharges are used in photocopiers.
Electric discharges can convey substantial energy to the electrodes at the ends of the discharge. A spark gap is used in internal combustion engines to ignite the fuel/air mixture on every power stroke. Spark gaps are also used to switch heavy currents in a Marx generator and to protect electrical apparatus. In electric discharge machining, multiple tiny electric arcs erode a conductive workpiece to a finished shape. Arc welding is used to assemble heavy steel structures, where the base metal is heated to melting by the arc's heat. An electric arc furnace sustains arc currents of tens of thousands of amperes and is used for steelmaking and the production of alloys and other products.
Examples
Examples of electric discharge phenomena include:
Brush discharge
Dielectric barrier discharge
Corona discharge
Electric glow discharge
Electric arc
Electrostatic discharge
Electric discharge in gases
Leader (spark)
Partial discharge
Streamer discharge
Vacuum arc
Townsend discharge
St. Elmo's fire
Lightning
Electric organ
See also
Debye sheath
Electrical breakdown
Electric discharge in gases
Lichtenberg figure
Space charge
References
Electrical phenomena
Plasma phenomena | Electric discharge | [
"Physics"
] | 374 | [
"Physical phenomena",
"Plasma physics",
"Plasma phenomena",
"Electrical phenomena",
"Plasma physics stubs"
] |
3,007,616 | https://en.wikipedia.org/wiki/HER2 | Receptor tyrosine-protein kinase erbB-2 is a protein that normally resides in the membranes of cells and is encoded by the ERBB2 gene. ERBB is abbreviated from erythroblastic oncogene B, a gene originally isolated from the avian genome. The human protein is also frequently referred to as HER2 (human epidermal growth factor receptor 2) or CD340 (cluster of differentiation 340).
HER2 is a member of the human epidermal growth factor receptor (HER/EGFR/ERBB) family. But contrary to other members of the ERBB family, HER2 does not directly bind ligand. HER2 activation results from heterodimerization with another ERBB member or by homodimerization when HER2 concentration are high, for instance in cancer. Amplification or over-expression of this oncogene has been shown to play an important role in the development and progression of certain aggressive types of breast cancer. In recent years the protein has become an important biomarker and target of therapy for approximately 30% of breast cancer patients.
Name
HER2 is so named because it has a similar structure to human epidermal growth factor receptor, or HER1. Neu is so named because it was derived from a rodent glioblastoma cell line, a type of neural tumor. ErbB-2 was named for its similarity to ErbB (avian erythroblastosis oncogene B), the oncogene later found to code for EGFR. Molecular cloning of the gene showed that HER2, Neu, and ErbB-2 are all encoded by the same orthologs.
Gene
ERBB2, a known proto-oncogene, is located at the long arm of human chromosome 17 (17q12).
Function
The ErbB family consists of four individual plasma membrane-bound receptor tyrosine kinases. One of which is erbB-2, and the other members being erbB-1, erbB-3 (neuregulin-binding; lacks kinase domain), and erbB-4. All four contain an extracellular ligand binding domain, a transmembrane domain, and an intracellular domain that can interact with a multitude of signaling molecules and exhibit both ligand-dependent and ligand-independent activity. Notably, no ligands for HER2 have yet been identified. HER2 can heterodimerise with any of the other three receptors and is considered to be the preferred dimerisation partner of the other ErbB receptors.
Dimerisation results in the autophosphorylation of tyrosine residues within the cytoplasmic domain of the receptors and initiates a variety of signaling pathways.
Signal transduction
Signaling pathways activated by HER2 include:
mitogen-activated protein kinase (MAPK)
phosphoinositide 3-kinase (PI3K/Akt)
phospholipase C γ
protein kinase C (PKC)
Signal transducer and activator of transcription (STAT)
In summary, signaling through the ErbB family of receptors promotes cell proliferation and opposes apoptosis, and therefore must be tightly regulated to prevent uncontrolled cell growth from occurring.
Clinical significance
Cancer
Amplification, also known as the over-expression of the ERBB2 gene, occurs in approximately 15-30% of breast cancers. HER2-positive breast cancers are well established as being associated with increased disease recurrence and a poor prognosis compared with other identifiably genetically distinct breast cancers with other known, or lack thereof, genetic markers that are thought to be associated with other breast cancers; however, drug agents targeting HER2 in breast cancer have significantly and positively altered the otherwise poor prognosis of the historically problematic difficulties associated with HER2-positive breast cancer. Over-expression is also known to occur in ovarian, stomach, adenocarcinoma of the lung and aggressive forms of uterine cancer, such as uterine serous endometrial carcinoma, e.g. HER2 is over-expressed in approximately 7-34% of patients with gastric cancer and in 30% of salivary duct carcinomas.
HER2 is colocalised and most of the time, coamplified with the gene GRB7, which is a proto-oncogene associated with breast, testicular germ cell, gastric, and esophageal tumours.
HER2 proteins have been shown to form clusters in cell membranes that may play a role in tumorigenesis.
Evidence has also implicated HER2 signaling in resistance to the EGFR-targeted cancer drug cetuximab.
The high expression of HER2 correlates with better survival in esophageal adenocarcinoma.
The high amplification of HER2 copy number positively contributes to the survival time of gastric cardia adenocarcinoma patients.
Mutations
Furthermore, diverse structural alterations have been identified that cause ligand-independent firing of this receptor, doing so in the absence of receptor over-expression. HER2 is found in a variety of tumours and some of these tumours carry point mutations in the sequence specifying the transmembrane domain of HER2. Substitution of a valine for a glutamic acid or a glutamine in the transmembrane domain can result in the constitutive dimerisation of this protein in the absence of a ligand.
HER2 mutations have been found in non-small-cell lung cancers (NSCLC) and can direct treatment.
As a drug target
HER2 is the target of the monoclonal antibody trastuzumab (marketed as Herceptin). Trastuzumab is effective only in cancers where HER2 is over-expressed. One year of trastuzumab therapy is recommended for all patients with HER2-positive breast cancer who are also receiving chemotherapy. Twelve months of trastuzumab therapy is optimal. Randomized trials have demonstrated no additional benefit beyond 12 months, whereas 6 months has been shown to be inferior to 12. Trastuzumab is administered intravenously weekly or every 3 weeks.
An important downstream effect of trastuzumab binding to HER2 is an increase in p27, a protein that halts cell proliferation. Another monoclonal antibody, Pertuzumab, which inhibits dimerisation of HER2 and HER3 receptors, was approved by the FDA for use in combination with trastuzumab in June 2012.
As of November 2015, there are a number of ongoing and recently completed clinical trials of novel targeted agents for HER2+ metastatic breast cancer, e.g. margetuximab.
Additionally, NeuVax (Galena Biopharma) is a peptide-based immunotherapy that directs "killer" T cells to target and destroy cancer cells that express HER2. It has entered phase 3 clinical trials.
It has been found that patients with ER+ (Estrogen receptor positive)/HER2+ compared with ER-/HER2+ breast cancers may actually benefit more from drugs that inhibit the PI3K/AKT molecular pathway.
Over-expression of HER2 can also be suppressed by the amplification of other genes. Research is currently being conducted to discover which genes may have this desired effect.
The expression of HER2 is regulated by signaling through estrogen receptors. Normally, estradiol and tamoxifen acting through the estrogen receptor down-regulate the expression of HER2. However, when the ratio of the coactivator AIB-3 exceeds that of the corepressor PAX2, the expression of HER2 is upregulated in the presence of tamoxifen, leading to tamoxifen-resistant breast cancer.
Among approved anti-HER2 therapeutics are also tyrosine kinase inhibitors (Lapatinib, Neratinib, and Tucatinib) and antibody-drug conjugates (ado-trastuzumab emtansine and trastuzumab deruxtecan).
Diagnostics
HER2 testing is performed on breast biopsy of breast cancer patients to assess prognosis and to determine suitability for trastuzumab therapy. It is important that trastuzumab is restricted to HER2-positive individuals as it is expensive and has been associated with cardiac toxicity. For HER2-positive tumors, the benefits of trastuzumab clearly outweigh the risks.
Tests are usually performed on breast biopsy samples obtained by either fine-needle aspiration, core needle biopsy, vacuum-assisted breast biopsy, or surgical excision.
Immunohistochemistry (IHC) is generally used to measure the amount of HER2 protein present in the sample, with fluorescence in situ hybridisation (FISH) being used on samples that are equivocal in IHC. However, in several locations, FISH is used initially, followed by IHC in equivocal cases.
Immunohistochemistry
By immunohistochemistry, the sample is given a score based on the cell membrane staining pattern.
Micrographs showing each score:
Fluorescence in situ hybridisation
FISH can be used to measure the number of copies of the gene which are present and is thought to be more reliable than immunohistochemistry. It usually uses chromosome enumeration probe 17 (CEP17) to count the amount of chromosomes. Hence, the HER2/CEP17 ratio reflects any amplification of HER2 as compared to the number of chromosomes. The signals of 20 cells are usually counted.
If the initial HER2 result is negative for a needle biopsy of a primary breast cancer, a new HER2 test may be performed on the subsequent breast excision.
Serum
The extracellular domain of HER2 can be shed from the surface of tumour cells and enter the circulation. Measurement of serum HER2 by enzyme-linked immunosorbent assay (ELISA) offers a far less invasive method of determining HER2 status than a biopsy and consequently has been extensively investigated. Results so far have suggested that changes in serum HER2 concentrations may be useful in predicting response to trastuzumab therapy. However, its ability to determine eligibility for trastuzumab therapy is less clear.
Interactions
HER2/neu has been shown to interact with:
CTNNB1,
DLG4,
Erbin,
GRB2,
HSP90AA1,
IL6ST,
MUC1,
PICK1 and
PIK3R2,
PLCG1, and
SHC1.
See also
SkBr3 Cell Line, over-expresses HER2
References
Further reading
External links
AACR Cancer Concepts Factsheet on HER2
Breast Friends for Life Network - A South African Breast Cancer Support Forum for HER2 Positive Women
HerceptinR : Herceptin Resistance Database for Understanding Mechanism of Resistance in Breast Cancer Patients. Sci. Rep. 4:4483
PDBe-KB provides an overview of all the structure information available in the PDB for Human Receptor tyrosine-protein kinase erbB-2
Clusters of differentiation
Tyrosine kinase receptors
Cancer treatments
Oncogenes
Breast cancer | HER2 | [
"Chemistry"
] | 2,341 | [
"Tyrosine kinase receptors",
"Signal transduction"
] |
3,007,735 | https://en.wikipedia.org/wiki/Skyquake | A skyquake is a phenomenon where a loud sound is reported to originate from the sky. It often manifests as a banging, or a horn-like noise. The sound may cause noticeable vibration in the ceiling or across a particular room. Those who experience skyquakes typically do not have a clear explanation for what caused them and they are perceived as mysterious. They have been heard in several locations around the world, several locations in the North Sea, the Ganges, Canada, Colombia, Japan, Finland, Australia, Italy, Ireland, India, The Netherlands, Norway, Tierra del Fuego in Argentina, the United Kingdom, the United States, Mexico, Malaysia (particularly Ipoh) and Indonesia (particularly Jakarta and Java).
Local names
Names (according to area) are:
Bangladesh: Barisal Guns
France: "bombes de mer", "canons de mer".
Indonesia: dentuman (lit: "clatter") or suara tembakan meriam (lit: "the sound of cannon fire").
Italy: "brontidi", "marina", "balza", "lagoni", "bomba", "rombo", "boato", "bonnito", "mugghio", "baturlio", "tromba", "rufa".
Japan: "uminari" (literally, "cries from the sea")
Netherlands and Belgium: "mistpoeffers", "zeepoeffers", "zeedoffers", "mistbommen", "gonzen", "balken", "onderaardse geruchten".
Philippines and Iran: "retumbos"
United States: "Guns of the Seneca" around Seneca Lake and Cayuga Lake, Seneca guns in the Southeast US
Latin America and Spain: "cielomoto"
elsewhere: "fog guns", "mistpouffers", "waterguns"
In 1804, they were reportedly heard during the Lewis and Clark Expedition near Great Falls. Meriwether Lewis wrote “since our arrival at the falls we have repeatedly witnessed a noise which proceeds from a direction a little to the N. of West as loud and resembling precisely the discharge of a piece of ordinance of 6 pounds at the distance of three miles.” William Clark added in his notes, “…a rumbling like Cannon at a great distance is heard to the west of us; the Cause we Can’t account.”
They have been reported from an Adriatic island in 1824; Western Australia, South Australia and Victoria in Australia; Belgium; frequently on calm summer days in the Bay of Fundy and Passamaquoddy Bay, New Brunswick, Canada; Lough Neagh in Northern Ireland; Scotland; Cedar Keys, Florida; Franklinville, New York in 1896; and northern Georgia in the United States.
Their sound has been described as being like distant but inordinately loud thunder while no clouds are in the sky large enough to generate lightning. Those familiar with the sound of cannon fire say the sound is nearly identical. The booms occasionally cause shock waves that rattle plates. Early white settlers in North America were told by the native Haudenosaunee Iroquois that the booms were the sound of the Great Spirit continuing his work of shaping the earth.
The terms "mistpouffers" and "Seneca guns" both originate in Seneca Lake, New York, and refer to the rumble of artillery fire. James Fenimore Cooper, author of The Last of the Mohicans, wrote "The Lake Gun" in 1850, a short story describing the phenomenon heard at Seneca Lake, which seems to have popularized the terms.
Hypotheses
Their origin has not been positively identified. Given the long time that they have been known and reported, but with no proposal experimentally confirmed, it seems likely that they occur for more than one reason. Proposed explainations have been:
Moderate-sized meteors causing sonic booms as they strike the lower atmosphere.
Gas explosions, either by ignition or sudden release of trapped deposits:
Gas escaping from vents in the Earth's surface.
With lakes, bio gas from decaying vegetation trapped beneath the lake bottoms suddenly bursting forth. (Plausible, since Cayuga Lake and Seneca Lake are large, deep lakes with millennia of deep deposition of organically enriched sediment.)
Explosive release of less volatile gases generated as limestone decay in underwater caves.
Underwater caves collapsing, and either the released air and/or a wave of water pressure vacuum abruptly arriving at the lake surface.
Volcanic eruptions (in places near known volcanic activity).
Military aircraft surreptitiously creating sonic booms. (This origin does not explain sounds heard before supersonic flight, but could be extended to include military cannon-fire practice.)
Earthquakes: Shallow earthquakes can generate sound waves with little ground vibration: The "booming" sound is heard only locally, near the epicenter.
Avalanches, either natural or human-caused (for avalanche control).
Weather: Distant thunder, or loud sounds from wind damage.
Atmospheric ducting of distant thunder or other loud sounds from far off. ("Ducting" is enhanced propagation of sound or radio waves over long distances, through the troposphere, by wave travel that's constrained between distinct air layers.)
Secondary atmospheric waves from plasma impacts of solar CMEs. CMEs generate plasma shock waves in space, similar to the sonic boom caused by aircraft flying faster than the speed of sound in Earth's atmosphere. The solar wind's equivalent of a sonic boom in the solar-system plasma medium can accelerate protons up to millions of miles per minute – as much as 40 percent of the speed of light. This is a proven source of auroras, but has never yet been shown to be sufficiently forceful and sufficiently abrupt to cause a "boom".
Possible resonance from solar and/or earth magnetic activity inducing sounds.
See also
Bell Island Boom, attributed to a lightning superbolt
List of meteor air bursts
List of unexplained sounds
Electrophonic hearing
References
Unidentified sounds
Natural disasters
Types of earthquake
Unexplained phenomena | Skyquake | [
"Physics"
] | 1,255 | [
"Weather",
"Physical phenomena",
"Natural disasters"
] |
3,007,899 | https://en.wikipedia.org/wiki/Antimycobacterial | An antimycobacterial is a type of medication used to treat Mycobacteria infections.
Types include:
Tuberculosis treatments
Leprostatic agents
Notes
Antibiotics | Antimycobacterial | [
"Biology"
] | 35 | [
"Antibiotics",
"Biocides",
"Biotechnology products"
] |
3,008,091 | https://en.wikipedia.org/wiki/Mathematics%20Subject%20Classification | The Mathematics Subject Classification (MSC) is an alphanumerical classification scheme that has collaboratively been produced by staff of, and based on the coverage of, the two major mathematical reviewing databases, Mathematical Reviews and Zentralblatt MATH. The MSC is used by many mathematics journals, which ask authors of research papers and expository articles to list subject codes from the Mathematics Subject Classification in their papers. The current version is MSC2020.
Structure
The MSC is a hierarchical scheme, with three levels of structure. A classification can be two, three or five digits long, depending on how many levels of the classification scheme are used.
The first level is represented by a two-digit number, the second by a letter, and the third by another two-digit number. For example:
53 is the classification for differential geometry
53A is the classification for classical differential geometry
53A45 is the classification for vector and tensor analysis
First level
At the top level, 64 mathematical disciplines are labeled with a unique two-digit number. In addition to the typical areas of mathematical research, there are top-level categories for "History and Biography", "Mathematics Education", and for the overlap with different sciences. Physics (i.e. mathematical physics) is particularly well represented in the classification scheme with a number of different categories including:
Fluid mechanics
Quantum mechanics
Geophysics
Optics and electromagnetic theory
All valid MSC classification codes must have at least the first-level identifier.
Second level
The second-level codes are a single letter from the Latin alphabet. These represent specific areas covered by the first-level discipline. The second-level codes vary from discipline to discipline.
For example, for differential geometry, the top-level code is 53, and the second-level codes are:
A for classical differential geometry
B for local differential geometry
C for global differential geometry
D for symplectic geometry and contact geometry
In addition, the special second-level code "-" is used for specific kinds of materials. These codes are of the form:
53-00 General reference works (handbooks, dictionaries, bibliographies, etc.)
53-01 Instructional exposition (textbooks, tutorial papers, etc.)
53-02 Research exposition (monographs, survey articles)
53-03 Historical (must also be assigned at least one classification number from Section 01)
53-04 Explicit machine computation and programs (not the theory of computation or programming)
53-06 Proceedings, conferences, collections, etc.
The second and third level of these codes are always the same - only the first level changes. For example, it is not valid to use 53- as a classification. Either 53 on its own or, better yet, a more specific code should be used.
Third level
Third-level codes are the most specific, usually corresponding to a specific kind of mathematical object or a well-known problem or research area.
The third-level code 99 exists in every category and means none of the above, but in this section.
Using the scheme
The AMS recommends that papers submitted to its journals for publication have one primary classification and one or more optional secondary classifications. A typical MSC subject class line on a research paper looks like
MSC Primary 03C90; Secondary 03-02;
History
According to the American Mathematical Society (AMS) help page about MSC, the MSC has been revised a number of times since 1940. Based on a scheme to organize AMS's Mathematical Offprint Service (MOS scheme), the AMS Classification was established for the classification of reviews in Mathematical Reviews in the 1960s. It saw various ad-hoc changes. Despite its shortcomings, Zentralblatt für Mathematik started to use it as well in the 1970s. In the late 1980s, a jointly revised scheme with more formal rules was agreed upon by Mathematical Reviews and Zentralblatt für Mathematik under the new name Mathematics Subject Classification. It saw various revisions as MSC1990, MSC2000 and MSC2010. In July 2016, Mathematical Reviews and zbMATH started collecting input from the mathematical community on the next revision of MSC, which was released as MSC2020 in January 2020.
The original classification of older items has not been changed. This can sometimes make it difficult to search for older works dealing with particular topics. Changes at the first level involved the subjects with (present) codes 03, 08, 12-20, 28, 37, 51, 58, 74, 90, 91, 92.
Relation to other classification schemes
For physics papers the Physics and Astronomy Classification Scheme (PACS) is often used. Due to the large overlap between mathematics and physics research it is quite common to see both PACS and MSC codes on research papers, particularly for multidisciplinary journals and repositories such as the arXiv.
The ACM Computing Classification System (CCS) is a similar hierarchical classification scheme for computer science. There is some overlap between the AMS and ACM classification schemes, in subjects related to both mathematics and computer science, however the two schemes differ in the details of their organization of those topics.
The classification scheme used on the arXiv is chosen to reflect the papers submitted. As arXiv is multidisciplinary its classification scheme does not fit entirely with the MSC, ACM or PACS classification schemes. It is common to see codes from one or more of these schemes on individual papers.
First-level areas
00: General (Includes topics such as recreational mathematics, philosophy of mathematics and mathematical modeling.)
01: History and biography
03: Mathematical logic and foundations (including model theory, computability theory, set theory, proof theory, and algebraic logic)
05: Combinatorics
06: Order, lattices, ordered algebraic structures
08: General algebraic systems
11: Number theory
12: Field theory and polynomials
13: Commutative algebra (Commutative rings and algebras)
14: Algebraic geometry
15: Linear and multilinear algebra; matrix theory
16: Associative rings and (associative) algebras
17: Non-associative rings and (non-associative) algebras
18: Category theory; homological algebra
19: -theory
20: Group theory and generalizations
22: Topological groups, Lie groups (and analysis upon them)
26: Real functions (including derivatives and integrals)
28: Measure and integration
30: Functions of a complex variable (including approximation theory in the complex domain)
31: Potential theory
32: Several complex variables and analytic spaces
33: Special functions
34: Ordinary differential equations
35: Partial differential equations
37: Dynamical systems and ergodic theory
39: Difference (equations) and functional equations
40: Sequences, series, summability
41: Approximations and expansions
42: Harmonic analysis on Euclidean spaces (including Fourier analysis, Fourier transforms, trigonometric approximation, trigonometric interpolation, and orthogonal functions)
43: Abstract harmonic analysis
44: Integral transforms, operational calculus
45: Integral equations
46: Functional analysis (including infinite-dimensional holomorphy, integral transforms in distribution spaces)
47: Operator theory
49: Calculus of variations and optimal control; optimization (including geometric integration theory)
51: Geometry
52: Convex (geometry) and discrete geometry
53: Differential geometry
54: General topology
55: Algebraic topology
57: Manifolds and cell complexes
58: Global analysis, analysis on manifolds (including infinite-dimensional holomorphy)
60: Probability theory and stochastic processes
62: Statistics
65: Numerical analysis
68: Computer science
70: Mechanics of particles and systems (including particle mechanics)
74: Mechanics of deformable solids
76: Fluid mechanics
78: Optics, electromagnetic theory
80: Classical thermodynamics, heat transfer
81: Quantum theory
82: Statistical mechanics, structure of matter
83: Relativity and gravitational theory (including relativistic mechanics)
85: Astronomy and astrophysics
86: Geophysics
90: Operations research, mathematical programming
91: Game theory, economics, social and behavioral sciences
92: Biology and other natural sciences
93: Systems theory; control (including optimal control)
94: Information and communication, circuits
97: Mathematics education
See also
Areas of mathematics
Mathematical knowledge management
MathSciNet
References
External links
MSC2020-Mathematical Sciences Classification System (PDF of MSC2020)
The Zentralblatt MATH page on the Mathematics Subject Classification. MSC2020 can be seen here.
Mathematics Subject Classification 2010 – the site where the MSC2010 revision was carried out publicly in an MSCwiki. A view of the whole scheme and the changes made from MSC2000, as well as PDF files of the MSC and ancillary documents are there. A personal copy of the MSC in TiddlyWiki form can be had also.
The American Mathematical Society page on the Mathematics Subject Classification.
Fields of mathematics
Mathematical classification systems | Mathematics Subject Classification | [
"Mathematics"
] | 1,796 | [
"nan"
] |
3,008,376 | https://en.wikipedia.org/wiki/Frangipane | Frangipane ( ) is a sweet almond-flavoured custard, typical in French pastry, used in a variety of ways, including cakes and such pastries as the Bakewell tart, conversation tart, Jésuite and pithivier. A French spelling from a 1674 cookbook is franchipane, with the earliest modern spelling coming from a 1732 confectioners' dictionary. Originally designated as a custard tart flavoured by almonds or pistachios, it came later to designate a filling that could be used in a variety of confections and baked goods.
It is traditionally made by combining two parts of almond cream (crème d’amande) with one part pastry cream (crème pâtissière). Almond cream is made from butter, sugar, eggs, almond meal, bread flour, and rum; and pastry cream is made from whole milk, vanilla bean, cornstarch, sugar, egg yolks or whole eggs, and butter. There are many variations on both of these creams as well as on the proportion of almond cream to pastry cream in frangipane.
On Epiphany, the French cut the king cake – a round cake made of frangipane layers – into slices to be distributed by a child known as le petit roi (the little king), who is usually hiding under the dining table. The cake is decorated with stars, a crown, flowers and a special bean hidden inside the cake. Whoever gets the piece of the frangipane cake with the bean is crowned "king" or "queen" for the following year.
Etymology
The word frangipane is a French term used to name products with an almond flavour. The word comes ultimately from the last name of Marquis Muzio Frangipani or Cesare Frangipani. The word first denoted the frangipani plant, from which was produced the perfume originally said to flavor frangipane. Other sources say that the name as applied to the almond custard was an homage by 16th-century Parisian chefs in name only to Frangipani, who created a jasmine-based perfume with a smell like the flowers to perfume leather gloves.
See also
List of almond dishes
List of custard desserts
List of pastries
References
Notes
Bibliography
"Frangipane." Oxford Companion to Food (1999), 316.
Almond dishes
Food ingredients
Custard desserts | Frangipane | [
"Technology"
] | 499 | [
"Food ingredients",
"Components"
] |
3,008,596 | https://en.wikipedia.org/wiki/Environmental%20change | Environmental change is a change or disturbance of the environment most often caused by human influences and natural ecological processes. Environmental changes include various factors, such as natural disasters,of human interferences, or animal interaction. Environmental change encompasses not only physical changes, but also factors like an infestation of invasive species.
See also
Climate variability and change
Environmental degradation
Human impact on the environment
Atlas of Our Changing Environment
Phenotypic plasticity
References
Ecology | Environmental change | [
"Biology"
] | 88 | [
"Ecology"
] |
3,008,683 | https://en.wikipedia.org/wiki/Visigothic%20art%20and%20architecture | The Visigoths entered Hispania (modern Spain and Portugal) in 415 and they rose to be the dominant people there until the Umayyad conquest of Hispania of 711 brought their kingdom to an end.
This period in Iberian art is dominated by their style. Visigothic art is generally considered in the English-speaking world to be a strain of Migration art, while the Portuguese- and Spanish-speaking worlds generally classify it as Pre-Romanesque.
Branches of Visigothic art include their architecture, crafts (especially jewellery), and their script.
Visigothic architecture
The only remaining examples of Visigothic architecture from the 6th century are the church of San Cugat del Vallés in Barcelona, the hermitage and church of Santa Maria de Lara in Burgos, Saint Frutuoso Chapel in Braga, the church of São Gião in Nazaré and the few remnants of the church at Cabeza de Griego in Cuenca. However, their style developed over the next centuries, though the prime remaining examples of it are mostly rural and often run-down. Some of the characteristics of their architecture are:
Generally basilican in layout, sometimes a Greek cross plan or, more rarely, a combination of the two. The spaces are highly compartmentalised.
Horseshoe arches without keystones.
A rectangular, exterior apse.
Use of columns and pillars with Corinthian capitals of unique design.
Barrel vaults with cupolas at the crosses.
Frequent use of marble as material.
Walls of ashlar blocks, occasionally alternating with Roman brickwork.
Decoration commonly of animal or plant motifs.
Examples include:
Church of San Juan Bautista, province of Palencia, Spain.
Crypt of San Antolín in the cathedral of Palencia, province of Palencia, Spain.
Church of Santa Comba in Bande, province of Ourense, Spain.
Chapel of San Xes (or San Ginés) de Francelos in Ribadavia, province of Ourense, Spain.
Church of San Pedro de la Mata (in ruins) in Sonseca, province of Toledo, Spain.
Church of Santa María de Melque in San Martín de Montalbán, province of Toledo, Spain.
Suso monastery at San Millán de la Cogolla, La Rioja, Spain.
Basilica of Santa María de Batres in Carranque, province of Toledo, Spain.
Hermitage of Santa María in Quintanilla de las Viñas, province of Burgos, Spain.
Church of Santa Lucía del Trampal near Alcuéscarprovince of Cáceres, Spain.
Crypt of the Monastery of San Salvador de Leyre, Navarre, Spain.
Church of San Miguel de los Fresnos (in ruins) in Fregenal de la Sierra, province of Badajoz, Spain.
Interior of church of San Pedro de la Nave, province of Zamora, Spain.
Saint Frutuoso Chapel in Braga, Portugal.
Church of São Gião in Nazaré, Portugal.
Church of San Pedro de la Nave in San Pedro de la Nave-Almendra.
See also
Treasure of Guarrazar
Verona Orational
Visigoths
Goths
References
"Visigothic art". In Encyclopædia Britannica Online.
Diego Marin, La Civilizacion Espanola, pp. 34 -47, 1969, Holt, Rinehart and Winston, New York.
Bradley Smith, Spain: A History In Art, pp. 52-56, Doubleday & Company, Garden City, NY, no publication date given, about 1971.
External links
Age of spirituality : late antique and early Christian art, third to seventh century from The Metropolitan Museum of Art
El portal del Arte Románico; Visigothic, Mozarabic and Romanesque art in Spain.
Architectural history
Early Germanic architecture | Visigothic art and architecture | [
"Engineering"
] | 779 | [
"Architectural history",
"Architecture"
] |
3,008,860 | https://en.wikipedia.org/wiki/National%20Childhood%20Vaccine%20Injury%20Act | The National Childhood Vaccine Injury Act (NCVIA) of 1986 (42 U.S.C. §§ 300aa-1 to 300aa-34) was signed into law by United States President Ronald Reagan as part of a larger health bill on November 14, 1986. NCVIA's purpose was to eliminate the potential financial liability of vaccine manufacturers due to vaccine injury claims to ensure a stable market supply of vaccines, and to provide cost-effective arbitration for vaccine injury claims. Under the NCVIA, the National Vaccine Injury Compensation Program (NVICP) was created to provide a federal no-fault system for compensating vaccine-related injuries or death by establishing a claim procedure involving the United States Court of Federal Claims and special masters.
Background
In the 1970s and 1980s, a controversy erupted related to the question of whether the whole-cell pertussis component of the DPT vaccine caused permanent brain injury known as pertussis vaccine encephalopathy in rare cases. No studies showed a causal connection, and later studies showed no connection of any type between the DPT vaccine and permanent brain injury. The alleged vaccine-induced brain damage proved to be an unrelated condition, infantile epilepsy. In 1990, an editorial in the Journal of the American Medical Association by a contractor of the vaccine manufacturers called the connection a "myth" and "nonsense".
However, before that point, criticism of the studies showing no connection and a few well-publicized anecdotal reports of permanent disability that were blamed on the DPT vaccine gave rise to anti-DPT movements in the 1970s. In the United States, low profit margins and an increase in vaccine-related lawsuits led many manufacturers to stop producing the DPT vaccine by the early 1980s. By 1985, vaccine manufacturers had difficulty obtaining liability insurance. The price of the DPT vaccine skyrocketed as a result, leading providers to curtail purchases, thus limiting availability. Only one company was still manufacturing pertussis vaccine in the US by the end of 1985. Because of this, Congress passed the National Childhood Vaccine Injury Act (NCVIA) in 1986, establishing a federal no-fault system to compensate victims of injury caused by mandated vaccines.
NCVIA provisions
Vaccine Adverse Event Reporting System
The NCVIA also mandates that all health care providers must report certain adverse events following vaccination to the Vaccine Adverse Event Reporting System (VAERS).
The NCVIA also established a committee from the Institute of Medicine (IOM) to review the existing literature on vaccine adverse events occurring after immunization.
National Vaccine Program Office
As a result of the NCVIA, the National Vaccine Program Office (NVPO) was established within the DHHS. The NVPO is responsible for coordinating immunization-related activities between all DHHS agencies, including the Centers for Disease Control and Prevention (CDC), Food and Drug Administration (FDA), National Institutes of Health (NIH) and the Health Resources and Services Administration (HRSA).
Vaccine Information Statements
The NCVIA requires that all health care providers who administer vaccines against diphtheria, tetanus, pertussis, polio, measles, mumps, rubella, hepatitis B, Haemophilus influenzae type b and varicella must provide a Vaccine Information Statement (VIS) to the vaccine recipient, their parent or legal guardian prior to each dose. A VIS must be given with every vaccination, including each dose in a multi-dose series. Each VIS contains a brief description of the disease, as well as the risks and benefits of the vaccine. Each VIS is developed by the CDC and distributed to state and local health departments as well as individual providers.
Place in vaccine misinformation
The law is brought up in arguments made by anti-vaccine activists. It has been faulted by those claiming that it has resulted in the end of civil liability for vaccines, in spite of its creation of the NVICP as an alternative avenue for compensation. The NVICP, with its burden of proof being more lenient than scientific standards of proof, has still resulted in a low award rate.
References
HRSA.gov – 'Vaccine Injury Table', United States Department of Health and Human Services (DHHS)
HRSA.gov – 'Commonly Asked Questions About The National Vaccine Injury Compensation Program', DHHS (last updated December 18, 2002)
External links
CDC.gov – 'Overview of Vaccine Safety', National Immunization Program
LSU.edu – 'Vaccine Law: National Childhood Vaccine Injury Act', Louisiana State University
VaccineSafety.edu – 'Institute for Vaccine Safety', Johns Hopkins University Bloomberg School of Public Health
1986 in American law
United States federal health legislation
Vaccination law
Vaccine Injury
Federal sovereign immunity in the United States
Vaccine controversies
Vaccination in the United States | National Childhood Vaccine Injury Act | [
"Chemistry",
"Biology"
] | 982 | [
"Biotechnology law",
"Vaccination law",
"Drug safety",
"Vaccine controversies",
"Vaccination"
] |
3,009,815 | https://en.wikipedia.org/wiki/Null%20%28mathematics%29 | In mathematics, the word null (from meaning "zero", which is from meaning "none") is often associated with the concept of zero or the concept of nothing. It is used in varying context from "having zero members in a set" (e.g., null set) to "having a value of zero" (e.g., null vector).
In a vector space, the null vector is the neutral element of vector addition; depending on the context, a null vector may also be a vector mapped to some null by a function under consideration (such as a quadratic form coming with the vector space, see null vector, a linear mapping given as matrix product or dot product, a seminorm in a Minkowski space, etc.). In set theory, the empty set, that is, the set with zero elements, denoted "{}" or "∅", may also be called null set. In measure theory, a null set is a (possibly nonempty) set with zero measure.
A null space of a mapping is the part of the domain that is mapped into the null element of the image (the inverse image of the null element). For example, in linear algebra, the null space of a linear mapping, also known as kernel, is the set of vectors which map to the null vector under that mapping.
In statistics, a null hypothesis is a proposition that no effect or relationship exists between populations and phenomena. It is the hypothesis which is presumed true—unless statistical evidence indicates otherwise.
See also
0
Null sign
References
Mathematical terminology
0 (number) | Null (mathematics) | [
"Mathematics"
] | 327 | [
"nan"
] |
3,010,111 | https://en.wikipedia.org/wiki/Wormwood%20%28Bible%29 | Wormwood (Ancient Greek: ἀψίνθιον (apsinthion) oψινθος (apsinthos) is a prophesied star or angel which appears in the Book of Revelation.
Hebrew Bible
The Biblical Hebrew word לענה (la'anah), translated into English as "wormwood", occurs nine times in the Hebrew Bible, seven times with the implication of bitterness and twice as a proper noun, in the Greek translation, naming the physical meteor in its orbit, in Revelation 8:11.
New Testament
The Greek word apsinthos, which is rendered with the English "wormwood", is mentioned only once in the New Testament, in the Book of Revelation:
Apsinthos is believed to refer to a plant of the genus Artemisia, used metaphorically to mean something with a bitter taste. The English rendering "wormwood" refers to the dark green oil produced by the plant, which was used to kill intestinal worms. In Revelation, it refers to the water being turned into wormwood, i.e. made bitter.
Interpretations
Certain commentators have held that this "great star" represents one of several important figures in political or ecclesiastical history: Matthew Henry mentions Augustulus, a 5th-century emperor of the Western Roman Empire, and Pelagius, deemed a heretic at the Council of Ephesus.
Other Bible dictionaries and commentaries view the term as a reference to a celestial being; for example, A Dictionary of the Holy Bible states that "the star called Wormwood seems to denote a mighty prince, or power of the air, the instrument, in its fall".
Historicist
Various religious groups and figures, including Seventh-day Adventists and the theologians Matthew Henry and John Gill, regard the verses of Revelation 8 as symbolic references to past events in human history. In the case of Wormwood, some historicist interpreters believe it represents the army of the Huns led by Attila, pointing to chronological consistencies between the timeline of prophecy they have accepted and the history of the Huns’ campaign in Europe. Others point to the heretical priest Arius, the Roman Emperor Constantine, Origen, or the ascetic monk Pelagius, who denied the doctrine of original sin.
Spiritual
The Swedenborgian New Church follows a spiritual interpretation of the star Wormwood based on other passages of scripture which mention gall and wormwood. The star signifies self-derived intelligence which departs from God, thus it falls from heaven. For the star to make the waters of rivers and fountains bitter signifies to falsify spiritual truths, as waters signify truths derived from the Word. In general, the Book of Revelation is seen as a prophecy of the corruption of the Christian churches in the End Times, which is followed by the New Church signified by the New Jerusalem.
Alternative interpretations
A number of Bible scholars consider the term Worm
' to be a purely symbolic representation of the bitterness that will fill the earth during troubled times, noting that the plant for which Wormwood is named, Artemisia absinthium, or Mugwort, Artemisia vulgaris, is a known biblical metaphor for things that are unpalatably bitter.Revelation in the Geneva Study Bible (1599) at bible.crosswalk.com
Chornobyl
Due to the Ukrainian word for Artemisia vulgaris being chornobyl'' , many have used the Chornobyl nuclear disaster in 1986 as definitive proof that the prophecy in the Book of Revelation is correct. The verses referring to a "star falling down and turning the waters bitter" are interpreted as the radioactive fallout from the disaster poisoning the environment around Chornobyl, leaving it uninhabitable.
In the town centre of Chornobyl, there is the Wormwood Star Memorial, which depicts an angel blowing a trumpet, recalling the biblical prophecy.
See also
List of angels in theology
References
External links
Revelation 8:11 The name of the star is called Wormwood
Angels in Christianity
Astronomical myths
Book of Revelation
Individual angels
New Testament words and phrases
Prophecy in Christianity
Water and Christianity | Wormwood (Bible) | [
"Astronomy"
] | 838 | [
"Astronomical myths"
] |
5,499,409 | https://en.wikipedia.org/wiki/Desmoglein | The desmogleins are a family of desmosomal cadherins consisting of proteins DSG1, DSG2, DSG3, and DSG4. They play a role in the formation of desmosomes that join cells to one another.
Pathology
Desmogleins are targeted in the autoimmune disease pemphigus.
Desmoglein proteins are a type of cadherin, which is a transmembrane protein that binds with other cadherins to form junctions known as desmosomes between cells. These desmoglein proteins thus hold cells together, but, when the body starts producing antibodies against desmoglein, these junctions break down, and this results in subsequent blister or vesicle formation.
References
External links
Cadherins
Single-pass transmembrane proteins
Protein families | Desmoglein | [
"Biology"
] | 176 | [
"Protein families",
"Protein classification"
] |
5,499,512 | https://en.wikipedia.org/wiki/Matching%20law | In operant conditioning, the matching law is a quantitative relationship that holds between the relative rates of response and the relative rates of reinforcement in concurrent schedules of reinforcement. For example, if two response alternatives A and B are offered to an organism, the ratio of response rates to A and B equals the ratio of reinforcements yielded by each response. This law applies fairly well when non-human subjects are exposed to concurrent variable interval schedules (but see below); its applicability in other situations is less clear, depending on the assumptions made and the details of the experimental situation. The generality of applicability of the matching law is subject of current debate.
The matching law can be applied to situations involving a single response maintained by a single schedule of reinforcement if one assumes that alternative responses are always available to an organism, maintained by uncontrolled "extraneous" reinforcers. For example, an animal pressing a lever for food might pause for a drink of water.
The matching law was first formulated by R.J. Herrnstein (1961) following an experiment with pigeons on concurrent variable interval schedules. Pigeons were presented with two buttons in a Skinner box, each of which led to varying rates of food reward. The pigeons tended to peck the button that yielded the greater food reward more often than the other button, and the ratio of their rates to the two buttons matched the ratio of their rates of reward on the two buttons.
Mathematical statement
If R and R are the rate of responses on two schedules that yield obtained (as distinct from programmed) rates of reinforcement Rf and Rf, the strict matching law holds that the relative response rate R / (R + R) matches, that is, equals, the relative reinforcement rate Rf / (Rf + Rf). That is,
This relationship can also be stated in terms of response and reinforcement ratios:
Alternatively stated, it states that there exists a constant for an individual animal, such that for any . That is, for an individual animal, the rate of response is proportional to rate of reinforcement for any task.
Deviations from matching, and the generalized matching law
A recent review by McDowell reveals that Herrnstein's original equation fails to accurately describe concurrent-schedule data under a substantial range of conditions. Three deviations from matching have been observed: undermatching, overmatching, and bias. Undermatching means that the response proportions are less extreme than the law predicts. Undermatching can happen if subjects too often switch between the two response options, a tendency that may be strengthened by reinforcers that happen to occur just after a subject switches. A changeover delay may be used to reduce the effectiveness of such post-switch reinforcers; typically, this is a 1.5 second interval after a switch when no reinforcer is presented. Overmatching is the opposite of undermatching, and is less common. Here the subjects response proportions are more extreme than reinforcement proportions. Overmatching may occur if there is a penalty for switching. A final deviation is bias, which occurs when subjects spend more time on one alternative than the matching equation predicts. This may happen if a subject prefers a certain environment, area in a laboratory, or method of responding.
These failures of the matching law have led to the development of the "generalized matching law", which has parameters that reflect the deviations just described. This law is a power function generalization of the strict matching (Baum, 1974), and it has been found to fit a wide variety of matching data.
This is more conveniently expressed in logarithmic form
The constants b and s are referred to as "bias" and "sensitivity" respectively. "Bias" reflects any tendency the subject may have to prefer one response over the other. "Sensitivity" reflects the degree to which the reinforcement ratio actually impacts the choice ratio. When this equation is plotted, the result is straight line; sensitivity changes the slope and bias changes the intercept of this line.
The generalized matching law accounts for high proportions of the variance in most experiments on concurrent variable interval schedules in non-humans. Values of b often depend on details of the experiment set up, but values of s are consistently found to be around 0.8, whereas the value required for strict matching would be 1.0.
The concurrent VI VI choice situation involves strong negative feedbacks: the longer the subject refrains from responding to an alternative, the higher his probability of payoff: switching is encouraged.
Processes underlying the distribution of responses
There are three ideas on how humans and animals maximize reinforcement, molecular maximizing, molar maximizing and melioration.
molecular maximizing: organisms always choose whichever response alternative is most likely to be reinforced at the time.
molar maximizing: organisms distribute their responses among various alternatives so as to maximize the amount of reinforcement they earn over the long run.
melioration: literally means to "make better"; organisms respond so as to improve the local rates of reinforcement for response alternatives. behavior keeps shifting towards the better of two alternatives until ratios are equal-which makes matching.
Theoretical importance
The matching law is theoretically important for several reasons. First, it offers a simple quantification of behavior that can be applied to a number of situations. Secondly, offers a lawful account of choice. As Herrnstein (1970) expressed it, under an operant analysis, choice is nothing but behavior set into the context of other behavior. The matching law thus challenges the idea that choice is an unpredictable outcome of free will, just as B.F. Skinner and others have argued. However this challenge becomes serious only if it applies to human behavior, as well as to the behavior of pigeons and other animals. When human participants perform under concurrent schedules of reinforcement, matching has been observed in some experiments, but wide deviations from matching have been found in others. Finally, if nothing else, the matching law is important because it has generated a great deal of research that has widened our understanding of operant control.
Relevance to psychopathology
The matching law, and the generalized matching law, have helped behavior analysts to understand some complex human behaviors, especially the behavior of children in certain conflict situations. James Snyder and colleague have found that response matching predicts the use of conflict tactics by children and parents during conflict bouts. This matching rate predicts future arrests. Even children's use of deviant talk appears to follow a matching pattern.
Notes
References
Baum, W.M. (1974). On two types of deviation from the matching law: Bias and undermatching. Journal of the Experimental Analysis of Behavior, 22, 231–42.
Bradshaw, C.M.; Szabadi, E. & Bevan, P. (1976). Behavior of humans in variable-interval schedules of reinforcement Journal of the Experimental Analysis of Behavior, 26, 135–41.
Davison, M. & McCarthy, D. (1988). The matching law: A research review. Hillsdale, NJ: Erlbaum.
Herrnstein, R.J. (1961). Relative and absolute strength of responses as a function of frequency of reinforcement. Journal of the Experimental Analysis of Behaviour, 4, 267–72.
Herrnstein, R.J. (1970). On the law of effect. Journal of the Experimental Analysis of Behavior, 13, 243–66.
Horne, P.J. & Lowe, C.F. (1993). Determinants of human performance on concurrent schedules. Journal of the Experimental Analysis of Behavior, 59, 29–60. .
Poling, A., Edwards, T. L., Weeden, M., & Foster, T. (2011). The matching law. Psychological Record, 61(2), 313-322.
Simon, C., & Baum, W. M. (2017). Allocation of Speech in Conversation. Journal of Experimental Analysis of Behavior, 107.
Behavioral concepts
Behaviorism | Matching law | [
"Biology"
] | 1,608 | [
"Behavior",
"Behavioral concepts",
"Behaviorism"
] |
5,499,529 | https://en.wikipedia.org/wiki/Palynivore | In zoology, a palynivore /pəˈlɪnəvɔːɹ/, meaning "pollen eater" (from Greek παλύνω palunō, "strew, sprinkle", and Latin, vorare, meaning "to devour") is an herbivorous animal which selectively eats the nutrient-rich pollen produced by angiosperms and gymnosperms. Most true palynivores are insects or mites. The category in its strictest application includes most bees, and a few kinds of wasps, as pollen is often the only solid food consumed by all life stages in these insects. However, the category can be extended to include more diverse species. For example, palynivorous mites and thrips typically feed on the liquid content of the pollen grains without actually consuming the exine, or the solid portion of the grain. Additionally, the list is expanded greatly if one takes into consideration species where either the larval or adult stage feeds on pollen, but not both. There are other wasps which are in this category, as well as many beetles, flies, butterflies, and moths. One such example of a bee species that only consumes pollen in its larval stage is the Apis mellifera carnica. There is a vast array of insects that will feed opportunistically on pollen, as will various birds, orb-weaving spiders and other nectarivores.
Pollen, the essential component of the palynivore diet, is a male gametophyte that is formed in the anther, or the male part of the flower. Pollen is needed to fertilize the female part of the flower, or gynoecium, and has a long history of consumption by various species. There is evidence that suggests palynivory dates back to at least the Permian period. It is likely that a coevolution has occurred between plants and palynivores in a form of mutualism, or the process by which two species individually benefit from the activity of the other. For example, palynivores benefit by receiving nutrients from the pollen, and thus the structure of the palynivore eye evolved to better interpret visual cues given by the pollen. Pollen benefits from the animal-plant interaction by being spread as the animal carries it from flower to flower, furthering the reproductive success of its respective flower. Thus, pollen has evolved to be more visually appealing to palynivores, and changed its surface texture to be more readily recognized by palynivore's tactile sensory receptors.
Evolution
The earliest evidence of palynivory can be traced back to the Silurian (444 million years ago (Mya) – 419 Mya) and early Devonian (419 Mya – 393 Mya) periods Fossil evidence from these periods suggests that early arthropods, with unspecialized mandibular mouthparts, engaged in spore-feeding behavior. Unlike pollen, which is solely produced by flowering plants, spores are asexual reproductive particles produced by primitive organisms such as ferns, fungi, and bacteria. Palynivory, which is thought to have derived from early spore-feeders, emerged much later during the Pennsylvanian era (323 Mya – 299 Mya). Much of the evidence relating to palynivory evolution has been linked to a change in the structure of mandibular mouthparts, allowing for easier pollen collection. Such evidence can be found in Coleoptera (beetles), the most diverse group of palynivores, wherein species have developed mouthparts for pollen collection in addition to the evolution of early mandibular appendages into specialized structures assisting in pollen consumption.
Furthermore, modern-day palynivore mouthpart adaptations can also be tied to the evolution of ancient palynivore mouthparts involved in nectar uptake. The beginnings of structures involved in nectar uptake can be found in early, unrelated insect clades. The evolution of these structures occurred in three distinct tracks: sponge-like labellum of flies and caddisflies, siphon structures in butterflies and moths, and glossa in wasps and bees. Within each track, further specialization of these structures has occurred. For example, in wasps and bees, eight variations of mouthpart structures incorporating glossa have been identified. The evolution of various structural and morphological adaptations of present-day palynivores has also been thought to have co-evolved with pollen grains.
The abundance and diversity of seed-bearing plant fossils identified from the Late Pennsylvanian suggest greater palynivore evolution and adaptations to the evolving plant fauna. Furthermore, this highlights the co-evolution of this behavior with plant species at the time. Based on the morphological features of fossil remnants of the era, early palynivores are hypothesized to have belonged to the diaphanopterodean, protorthopteran, and hemipteroid taxonomic groups. Following this period, evolution and more specialized adaptations in palynivore mouthparts and pollen or prepollen found in the gut of fossilized insects showed convergence into three major lineages: Orthoptera (grasshoppers, crickets, and locusts), Coleoptera, Diptera (flies), and Hymenoptera (wasps, sawflies, bees, and ants). Currently, almost all palynivores are in five insect orders believed to have come about during the early Mesozoic period (248 Mya - 65 Mya): Coleoptera, Diptera, Thysanoptera (thrips), Hymenoptera, and Lepidoptera (butterflies and moths).
Adaptations of palynivores
Numerous species of insects (bees, wasps, ants, beetles, flies, butterflies, moths), mites, spiders, and birds consume pollen as a food source. To more efficiently collect pollen, palynivores have evolved various adaptations in their body parts and behavior. These adaptations include specialized mouthparts, hair, digestive systems, and patterns of reproduction and foraging. Although all palynivores eat pollen, they do so to varying degrees and ways, so consequently their adaptations also differ. Bees and ants, for example, are insects that place different amounts of emphasis on pollen in their diets.
Bees
Bees, part of the superfamily Apoidea, engage in palynivory extensively, especially in providing pollen for their offspring. To effectively collect, transport, and consume pollen, bees have evolved specialized morphological and behavioral traits. To forage for pollen, bees must first find sources of pollen, which they do so through chemical, visual, and tactile signals given by flowers that have co-evolved adaptations for this purpose, since most flowering plants benefit from the pollination that occurs while bees collect and transport pollen. Visual signals especially help guide bees to flowers. With sight adaptations such as the ability to see ultraviolet light, bees home in on the color pattern "targets" of flower petals that guide bees to nectar and pollen. They gather and store pollen together with nectar on specialized hairs and evolved scopal or corbicular constructions on their bodies. Bees have also evolved behavioral adaptations that involve some degree of learning. Most bees are also either oligolectic or polylectic, where they target specific or more general groups of flowering plants respectively, and their foraging patterns overlap significantly closely during the day and/or seasonally to the bloom periods of these targeted flowers. In the nest, bees will also communicate the locations of good foraging patches to other worker bees in a process called a waggle dance. Bees often favor certain foraging patches, and while evidence shows that bumblebees for instance are flexible in their foraging patterns, deciding on different types of flowers based on the pollen's protein:lipid ratios, these patterns directly influence the genetics of the flowering plant populations around them.
Ants
Ants, as part of the order Hymenoptera, are related to bees and similarly forage outside of their nests to transport protein back for their offspring. While pollen is not the sole or primary food source, evidence from studies done on ants species in genera such as Zacryptocerus, Cephalotes (turtle ants), Camponotus (carpenter ants), Crematogaster (acrobat ants), and Odontomachus (trap-jaw ants) show that pollen is both targeted for consumption and eaten opportunistically. In foraging, ants cannot fly to flowers to take pollen directly. Instead, they collect it from places where pollen has fallen or the wind has carried pollen to. Ants commonly store liquid food in their foregut and later regurgitate it to feed their offspring in the home nest. Several species of neotropical ants, turtle ants, for example, collect pollen from leaves and store it in their bodies to later regurgitate. During this process, they produce compressed masses of pollen called pellets, "infrabuccal pellets" in turtle ants, that allow for greater efficiency in transporting pollen. After ant offspring or worker ants consume the nutrient-rich parts of the pollen from these pellets, the membranes of pollen, unable to be digested, are then discarded.
Future of palynivores
Palynivores and flowering plants
Palynivores are essential to spreading the genes of flowering plants via the use of pollen which is the vector for genetic diversity in these plants. While wind and other natural resources can help in the process of spreading pollen, they are not specific and do not provide as direct a service as palynivores who although they eat the pollen also work to move the pollen from one plant to another thereby participating in pollination services. Over the past decade, there has been a decline in palynivore species worldwide that has had drastic consequences for flowering plants. As the palynivore population decreases, so do the pollination services they provide. This in turn lowers the reproductive success of flowering plants and causes an overall decline in the population of flowering plants and the number of species of flowering plants.
Specific versus general palynivores
Palynivores can generally be grouped in two categories: specific and general. Specific palynivores exhibit oligolecty, a sympathetic relationship with a specific genus or species of flowering plants, while general palynivores can pollinate a wide range of plants. Because of the specialty of certain types of palynivores such as honey bees, their life cycles have adapted to be closely correlated with the flowering periods of certain species of plants. However, when the pollination and flowering periods of these plants change because of seasonal variations caused by climate change, the palynivore life cycles are no longer in synchronization with that of the plant, thereby causing a decline in both populations. General palynivores on the other hand are adapted to consume pollen from and pollinate a wide range of different flowering plants with different flowering periods. The decline in specific palynivores can consequently lead to an increase in populations of general palynivores due to a decrease in competition and the increase in availability of resources.
Bumblebee populations
The interaction between general and specific species is best shown through members of the genus Bombus, more commonly known as bumblebees. Bumblebees have shown evidence of population decline within both Belgium and the UK with six of the sixteen non-parasitic bumblebees showing considerable decline and four showing possible signs of decline. These observational studies have shown that this decline has been similarly mirrored in the populations of wild plants with which these bumblebees correspond. However, this decline has not been prevalent among all populations of bumblebees. While many populations of bumblebees have shown a decline, there have been others that have stayed constant or even increased. In the same study of sixteen non-parasitic bumblebees there were six populations that stayed constant or even increased over the course of the study.
Causes of palynivore decline
Research has shown that a range of different environmental changes and climate changes such as habitat fragmentation, the introduction of different agrochemicals, and global warming are projected to lead to a decrease in palynivore populations and consequently a decrease in pollination services.
Habitat fragmentation
For many palynivores, especially colony insects such as bees and ants, suitable habitats are very important and must meet specific requirements. Habitat fragmentation can make these habitats inadequate to provide suitable and sustainable floral resources and suitable nesting sites within a reasonable flight range from each other. Depending on whether the pollinator is specific or general, the needs for the population may be different.
Specific palynivores
For specific palynivores exhibiting oligolecty, the adult seasonal emergence must coincide with the host plant's seasonal bloom. With these specific constraints in place, it can be inferred that specific palynivores must be located are heavily dependent on the seasonal variation of their host plants and the loss of even a small portion of their habitat can have drastic repercussions on the population size.
General palynivores
For general palynivores their foraging periods typically last longer than the seasonal bloom of one host. General palynivores must be located within flying distance of multiple different patches of floral plants each with their own flowering periods. Their survival is dependent on their ability to access each of these flower patches at different times during the season and inability to access specific patches due to either obstruction or destruction of these patches can result in decreased population size.
Agrochemicals
Agrochemical is short for agricultural chemical and have largely been used in farms and gardens to deter and kill insect pests. One common agrochemical is neonicotinoids which are highly neurotoxic to insects and mimic their acetylcholine neurotransmitters. When applied, neonicotinoids are typically sprayed widely and persist on the soil, in the water, and are taken up by plants. They are toxic and enter into the insect's body resulting in the impairment of foraging success, brood and larval development, and memory and learning as well as causing harmful effects on the nervous system, immune system, and hygiene of the insect. All of these factors negatively impact colony performance and have the potential to lead to colony collapse for both bees and ants.
Global warming
Climate change or global warming has resulted in higher average temperatures worldwide which has had significant repercussions on the foraging success of palynivores. Plants have experienced earlier flower and maturity both of which have been shown to be associated with warmer spring temperatures. Since the reproductive cycles of many palynivores are intimately linked to the flowering cycles of their host plants, many palynivore species have not been able to keep up with this change in flowering cycles of many host plants. This has resulted in a drastic decrease in the populations of many specific palynivores and their host plants. However an increase in general palynivore populations has also been recorded. This rise can be attributed to the decrease in competition for these certain host plants as well as the general palynivore's ability to adapt to a changing food source.
Future actions
There has been a general decline in plant and palynivore species diversity which is predicted to continue with the current trends in the release of greenhouse gasses and climate change. Given the extent of current research and evidence depicting the correlation between palynivore decline and a decline in pollinating plants' reproductive success, below are proposed steps that could potentially mitigate the loss of palynivore species.
Restoring and protecting palynivore habitat in the form of the floral reserves of threatened migratory palynivores
Planting more native plants to attract native palynivores
Increasing the available habitat for palynivores in and around croplands and gardens
Mitigating the use of pesticides, agrochemicals, and herbicides
References
Herbivory
Animals by eating behaviors | Palynivore | [
"Biology"
] | 3,267 | [
"Behavior",
"Animals by eating behaviors",
"Eating behaviors",
"Herbivory",
"Ethology"
] |
5,499,616 | https://en.wikipedia.org/wiki/NUTS%20statistical%20regions%20of%20Hungary | The NUTS codes of Hungary have three levels:
Codes
Local administrative units
Below the NUTS levels, the two LAU (Local Administrative Units) levels are:
The LAU codes of Hungary can be downloaded here:
Changes in NUTS 2016 classification
The NUTS classification is regularly updated to reflect changes and modifications proposed by Member States. As part of this process the European Commission has adopted changes concerning Hungary in December 2016. The new classification that has been introduced have split the region Central Hungary in two: Budapest (previously HU101) and Pest county (previously HU102). The new classification is in use since 1 January 2018.
See also
ISO 3166-2 codes of Hungary
FIPS region codes of Hungary
Regions of Hungary
Counties of Hungary
Districts of Hungary (from 2013)
Subregions of Hungary (until 2013)
Administrative divisions of the Kingdom of Hungary (until 1918)
Counties of the Kingdom of Hungary
Administrative divisions of the Kingdom of Hungary (1941–44)
List of cities and towns of Hungary
Sources
Hierarchical list of the Nomenclature of territorial units for statistics - NUTS and the Statistical regions of Europe
Overview map of EU Countries - NUTS level 1
MAGYARORSZÁG - NUTS level 2
MAGYARORSZÁG - NUTS level 3
Correspondence between the NUTS levels and the national administrative units
List of current NUTS codes
Download current NUTS codes (ODS format)
Counties of Hungary, Statoids.com
External links
Eurostat - Portrait of the regions (forum.europa.eu.int)
Comparative analysis of some Hungarian regions by using “COCO” method (DOC file) (HTML version)
Magyarország – NUTS level 3 (PDF; at the website of the Hungarian Prime Minister's Office )
Regions of Hungary (at Hungary.hu, the Government Portal of Hungary)
Hungary and the regions
Hungary
Nuts | NUTS statistical regions of Hungary | [
"Mathematics"
] | 358 | [
"Nomenclature of Territorial Units for Statistics",
"Statistical concepts",
"Statistical regions"
] |
5,499,671 | https://en.wikipedia.org/wiki/Soil%20production%20function | Soil production function refers to the rate of bedrock weathering into soil as a function of soil thickness. A general model suggests that the rate of physical weathering of bedrock (de/dt) can be represented as an exponential decline with soil thickness:
where h is soil thickness [m], P0 [mm/year] is the potential (or maximum) weathering rate of bedrock and k [m−1] is an empirical constant.
The reduction of weathering rate with thickening of soil is related to the exponential decrease of temperature amplitude with increasing depth below the soil surface, and also the exponential decrease in average water penetration (for freely-drained soils). Parameters P0 and k are related to the climate and type of parent material. The value of P0 was found to range from 0.08 to 2.0 mm/yr for sites in northern California, and 0.05–0.14 mm/yr for sites in southeastern Australia. Meanwhile values of k do not vary significantly, ranging from 2 to 4 m−1.
Several landscape evolution models have adopted the so-called humped model. This model dates back to G.K. Gilbert's Report on the Geology of the Henry Mountains (1877). Gilbert reasoned that the weathering of bedrock was fastest under an intermediate thickness of soil and slower under exposed bedrock or under thick mantled soil. This is because chemical weathering requires the presence of water. Under thin soil or exposed bedrock water tends to run off, reducing the chance of the decomposition of bedrock.
See also
Biorhexistasy
Hillslope evolution
Pedogenesis
Soil functions
Notes and references
Further reading
Mathematical modeling
Pedology | Soil production function | [
"Mathematics"
] | 339 | [
"Applied mathematics",
"Mathematical modeling"
] |
5,499,772 | https://en.wikipedia.org/wiki/Vernier%20thruster | A vernier thruster is a rocket engine used on a spacecraft or launch vehicle for fine adjustments to the attitude or velocity. Depending on the design of a craft's maneuvering and stability systems, it may simply be a smaller thruster complementing the main propulsion system, or it may complement larger attitude control thrusters, or may be a part of the reaction control system.
The name is derived from vernier calipers (named after Pierre Vernier) which have a primary scale for gross measurements, and a secondary scale for fine measurements.
Vernier thrusters are used when a heavy spacecraft requires a wide range of different thrust levels for attitude or velocity control, as for maneuvering during docking with other spacecraft.
On space vehicles with two sizes of attitude control thrusters, the main ACS (Attitude Control System) thrusters are used for larger movements, while the verniers are reserved for smaller adjustments.
Due to their weight and the extra plumbing required for their operation, vernier rockets are seldom used in new designs.
Instead, as modern rocket engines gained better control, larger thrusters could also be fired for very short pulses, resulting in the same change of momentum as a longer thrust from a smaller thruster.
Vernier thrusters are used in rockets such as the R-7 for vehicle maneuvering because the main engine is fixed in place. For earlier versions of the Atlas rocket family (prior to the Atlas III), in addition to maneuvering, the verniers were used for roll control, although the booster engines could also perform this function. After main engine cutoff, the verniers would execute solo mode and fire for several seconds to make fine adjustments to the vehicle attitude. The Thor/Delta family also used verniers for roll control but were mounted on the base of the thrust section flanking the main engine.
Examples
The R-7 rocket family, with over 1700 successful launches to date, still depends on the S1.358000 vernier thrusters in its first and second stage. Most of the larger Soviet missiles and launch vehicles also used verniers. Examples include the RD-8 on the Zenit rocket family, the RD-855 and RD-856 on the R-36, and the RD-0214 on the Proton rocket family.
On the SM-65 Atlas, the LR-101 verniers were used for roll control and to fine-tune the vehicle attitude after the main engine cutoff. The Delta II and Delta III rocket also used the LR-101 for vehicle roll maneuver since one engine cannot do a roll maneuver (although the later GEM 46 had thrust vectoring nozzle, only three were equipped with this feature and only ignited a brief moment during the ascent).
The Space Shuttle had six vernier engines or thrusters in its "Vernier Reaction Control System" (VRCS). The VRCS could also deliver a gentle steady thrust. This was regularly used to boost the International Space Station while docked: for example during STS-130 commander George Zamka and pilot Terry Virts fired Endeavour's VRCS for a duration of 33 minutes to attain an orbit between .
See also
Space propulsion
Cold gas thruster
Vernier throttle
References
Spacecraft components
Spacecraft attitude control | Vernier thruster | [
"Astronomy"
] | 658 | [
"Rocketry stubs",
"Astronomy stubs"
] |
5,500,097 | https://en.wikipedia.org/wiki/Washboarding | Washboarding or corrugation is the formation of periodic, transverse ripples in the surface of gravel and dirt roads. Washboarding occurs in dry, granular road material with repeated traffic, traveling at speeds above . Washboarding creates an uncomfortable ride for the occupants of traversing vehicles and hazardous driving conditions for vehicles that travel too fast to maintain traction and control.
Mechanism
Washboarding or corrugation of roads comprises a series of ripples, which occur with the passage of wheels rolling over unpaved roads at speeds sufficient to cause bouncing of the wheel on the initially unrippled surface and take on the appearance of a laundry washboard. Most studies of washboarding pertain to granular materials, including sand and gravel. However, other work suggests that the phenomenon may occur in material which has some binding of particles, e.g. clay-like soils.
Highway department experts in the mid-1920s were aware that traffic volume and speed were primary causes of corrugations on gravel roads and cited the role of drive wheels tossing material as a factor.
Laboratory-scale studies of the phenomenon typically employ a wheel or a blade, which is towed behind a pivot point, tracing a circular path through a pan of the material under examination. These studies have investigated a variety of granular and viscous, even fluid, materials. In the laboratory, washboarding has been studied for a range of parameters, including the thickness and grain size of the material for varied wheel sizes, shapes, and masses. Experiments produced ripples for each parameter, above a threshold speed, when the wheel (or blade) began to bounce. Experiments also show that the pattern can move either against the direction of motion or in the direction of motion. They also show that a passive, non-driving wheel suffices to create corrugations and that displacement of material, rather than ejection, is the dominant mechanism.
Several articles about real-life washboarding on roads cite South Dakota Local Transportation Assistance Program (LTAP) Special Bulletin #29, “Dealing with Washboarding,” by Ken Skorseth. Those sources attribute washboarding to three causes: dry granular materials, vehicle speeds, and the quality of the granular material. Other factors cited include vehicle speed, traffic volume, and hard acceleration or braking. The sources also claim that light vehicles are more likely to cause washboarding than heavy trucks.
Maintenance
Highway department guidance suggests that choice of gravel can be key to mitigating washboarding. They cite "sieve analysis" tests that use a series of screens or sieves to characterize the sizes of particles contained within a gravel sample. Highway department guidance suggests a range of particle sizes from stones that are in the range, mixed with progressively finer particles to include a small fraction of fine particles that bind the larger particles together. They also mention the role of equipment that can re-blend and smooth surfaces that have corrugated.
In 1925, the Nevada Department of Highways advocated mitigating corrugations with crushed pit-run gravel, using material and smaller, including only the fines from crushing. Contemporaneous advice from Colorado was to use a well-graded gravel, not exceeding and including 25–40% fines passing a sieve, but not more than 5% passing a #10 (2.0-mm) sieve. The maintenance advice from Colorado was to drag or grade the road frequently, applying light volumes of new gravel with minimal sand content and providing good drainage with a crown. The same source advises reduction of traffic speed.
Guidance based on South Dakota LTAP Special Bulletin #29 and FHWA guidance (2000) from the same source suggests that the surface gravel "should be a blend of stone, sand and fines that will compact into a dense, tight mass with an almost impervious surface." It emphasizes the proper gradation of gravel—100% passing the ) sieve—to have fractured stone to "interlock" and 4–15% fines passing the #200 (75-μm) sieve to act as a binder and create cohesiveness in the gravel; substituting other binders, such as clay is also recommended. Alternately, one can incorporate reclaimed asphalt in a half-and-half blend with quarried gravel to improve the binding properties of the surface. For existing washboarded surfaces, the bulletin recommends using a grader to cut and blend existing material to a depth one inch or more below the bottom of the washboarded segment and then add the new material into the top layer. Useful equipment includes a blade with rotating scarifying teeth or a replaceable bit-type cutting edge attached to the moldboard blade of the earth-moving equipment.
References
External links
Driving on a washboard road (Slow motion)
Roads
Road hazards
Pattern formation | Washboarding | [
"Technology"
] | 972 | [
"Road hazards"
] |
5,501,493 | https://en.wikipedia.org/wiki/Quark-nova | A quark-nova is the hypothetical violent explosion resulting from the conversion of a neutron star to a quark star. Analogous to a supernova heralding the birth of a neutron star, a quark nova signals the creation of a quark star. The term quark-novae was coined in 2002 by Dr. Rachid Ouyed (currently at the University of Calgary, Canada) and Drs. J. Dey and M. Dey (Calcutta University, India).
The nova process
When a neutron star spins down, it may convert to a quark star through a process known as quark deconfinement. The resultant star would have quark matter in its interior. The process would release immense amounts of energy, perhaps explaining the most energetic explosions in the universe; calculations have estimated that as much as 1046 J could be released from the phase transition inside a neutron star. Quark-novae may be one cause of gamma ray bursts. According to Jaikumar and collaborators, they may also be involved in producing heavy elements such as platinum through r-process nucleosynthesis.
Candidates
Rapidly spinning neutron stars with masses between 1.5 and 1.8 solar masses are hypothetically the best candidates for conversion due to spin down of the star within a Hubble time. This amounts to a small fraction of the projected neutron star population. A conservative estimate based on this, indicates that up to two quark-novae may occur in the observable universe each day.
Hypothetically, quark stars would be radio-quiet, so radio-quiet neutron stars may be quark stars.
Observations
Direct evidence for quark-novae is scant; however, recent observations of supernovae SN 2006gy, SN 2005gj and SN 2005ap may point to their existence.
See also
References
External links
Quark-novae produce neutrino bursts, which can be detected by neutrino observatories
Quark Stars Could Produce Biggest Bang (SpaceDaily) June 7, 2006
Quark Nova Project animations (University of Calgary)
Quark stars
Supernovae
Hypothetical astronomical objects | Quark-nova | [
"Chemistry",
"Astronomy"
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"Hypothetical astronomical objects",
"Explosions",
"Astronomical objects"
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5,501,614 | https://en.wikipedia.org/wiki/Radio-quiet%20neutron%20star | A radio-quiet neutron star is a neutron star that does not seem to emit radio emissions, but is still visible to Earth through electromagnetic radiation at other parts of the spectrum, particularly X-rays and gamma rays.
Background
Most detected neutron stars are pulsars, and emit radio-frequency electromagnetic radiation. About 700 radio pulsars are listed in the Princeton catalog, and all but one emit radio waves at the 400 MHz and 1400 MHz frequencies. That exception is Geminga, which is radio quiet at frequencies above 100 MHz, but is a strong emitter of X-rays and gamma rays.
In all, ten bodies have been proposed as rotation-powered neutron stars that are not visible as radio sources, but are visible as X-ray and gamma ray sources. Indicators that they are indeed neutron stars include them having a high X-ray to lower frequencies emission ratio, a constant X-ray emission profile, and coincidence with a gamma ray source.
Hypotheses
Quark stars, hypothetical neutron star-like objects composed of quark matter, have been proposed to be radio-quiet.
More plausibly, however, radio-quiet neutron stars may simply be pulsars which do not pulse in our direction. As pulsars spin, it is hypothesized that they emit radiation from their magnetic poles. When the magnetic poles do not lie on the axis of rotation, and cross the line of sight of the observer, one can detect radio emission emitted near the star's magnetic poles. Due to the star's rotation this radiation appears to pulse, colloquially called the "lighthouse effect". Radio-quiet neutron stars may be neutron stars whose magnetic poles do not point towards the Earth during their rotation.
The group of radio-quiet neutrons stars informally known as the Magnificent Seven are thought to emit mainly thermal radiation.
Possibly some powerful neutron star radio emissions are caused by a positron-electron jet emanating from the star blasting through outer material such as a cloud or accretion material. Note some radio quiet neutron stars listed in this article do not have accretion material.
Magnetars
Magnetars, the most widely accepted explanation for soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs), are often characterized as being radio-quiet. However, magnetars can produce radio emissions, but the radio spectrums tend to be flat, with only intermittent broad pulses of variable length.
List of radio-quiet neutron stars
X-ray Dim Isolated Neutron Stars
Can be classified as XDINS (X-ray Dim Isolated Neutron Stars), XTINS (X-ray Thermal Isolated Neutron Stars), XINS (X-ray Isolated Neutron Stars), TEINS (Thermally Emitting Neutron Star), INS (Isolated Neutron Stars).
Defined as thermally emitting neutron stars of high magnetic fields, although lower than that of magnetars. Identified in thermal X-rays, and thought to be radio-quiet.
A group of seven individual, physically similar and relatively nearby neutron stars nicknamed The Magnificent Seven, consisting of:
RX J185635-3754
RX J0720.4-3125
RBS1556
RBS1223
RX J0806.4-4132
RX J0420.0-5022
MS 0317.7-6647
1RXS J214303.7+065419/RBS 1774
Compact Central Objects in Supernova remnants
Compact Central Objects in Supernova remnants (CCOs in SNRs) are identified as being radio-quiet compact X-ray sources surrounded by supernova remnants. They have thermal emission spectra, and lower magnetic fields than XDINSs and magnetars.
RX J0822-4300 (1E 0820–4247) in the Puppis A supernova remnant (SNR G260.4-3.4).
1E 1207.4-5209 in the PKS 1209-51/52 supernova remnant (SNR G296.5+10).
RXJ0007.0+7302 (in SNR G119.5+10.2, CTA1)
RXJ0201.8+6435 (in SNR G130.7+3.1, 3C58)
1E 161348–5055 (in SNR G332.4-0.4, RCW103)
RXJ2020.2+4026 (in SNR G078.2+2.1, γ–Cyg)
Other neutron stars
IGR J11014-6103: a runaway pulsar ejected from a supernova remnant.
See also
Neutron star merger
Rotating radio transient
IRAS 00500+6713 (in 10,000 y)
Notes
References
Star types | Radio-quiet neutron star | [
"Astronomy"
] | 1,008 | [
"Star types",
"Astronomical classification systems"
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5,501,781 | https://en.wikipedia.org/wiki/Cohobation | In pre-modern chemistry and alchemy, cohobation was the process of repeated distillation of the same matter, with the liquid drawn from it (successive redistillation); that liquid being poured again and again upon the matter left at the bottom of the vessel. Cohobation is a kind of circulation, only differing from it in this, that the liquid is drawn off in cohobation, as in common distillation, and thrown back again; whereas in circulation, it rises and falls in the same vessel, without ever being drawn out.
Cohobation is not recognized as a useful process in modern chemistry. Indeed, it is equivalent to performing the same distillation a number of times and does not increase the purity of the distillate or alter the residue any more than would be done by maintaining it at elevated temperature for the same period of time. The Dean-Stark trap does involve returning some distillate to the reaction flask: a solution is distilled and the condensed liquid is collected in a tube wherein water settles to the bottom and is drained out, while an organic solvent returns to the boiling solution. However, the process is not manual, most of the solvent does not leave the reaction flask, and the apparatus achieves a useful purpose (removing water from the reaction mixture). Circulation, on the other hand, is approximately the same as reflux, where a solution is maintained at its boiling point by condensing the distilling vapors and returning them directly to the reaction mixture.
References
Alchemical processes
Distillation
Chemical processes
az:Rektifikasiya
ba:Ректификация
bg:Ректификация
cs:Rektifikace (chemie)
de:Rektifikation (Verfahrenstechnik)
eo:Rektifikilo
et:Rektifikatsioon
hr:Rektifikacija (kemija)
hy:Ռեկտիֆիկացում
kk:Ректификаттау
ky:Ректификация
lv:Rektificēšana
ru:Ректификация
sl:Rektifikacija (kemija)
sv:Rektifikation
uk:Ректифікація
uz:Rektifikatsiya | Cohobation | [
"Chemistry"
] | 508 | [
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"Chemical processes",
"Distillation",
"Alchemical processes",
"nan",
"Chemical process engineering"
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5,501,977 | https://en.wikipedia.org/wiki/Zero-order%20hold | The zero-order hold (ZOH) is a mathematical model of the practical signal reconstruction done by a conventional digital-to-analog converter (DAC). That is, it describes the effect of converting a discrete-time signal to a continuous-time signal by holding each sample value for one sample interval. It has several applications in electrical communication.
Time-domain model
A zero-order hold reconstructs the following continuous-time waveform from a sample sequence x[n], assuming one sample per time interval T:
where is the rectangular function.
The function is depicted in Figure 1, and is the piecewise-constant signal depicted in Figure 2.
Frequency-domain model
The equation above for the output of the ZOH can also be modeled as the output of a linear time-invariant filter with impulse response equal to a rect function, and with input being a sequence of dirac impulses scaled to the sample values. The filter can then be analyzed in the frequency domain, for comparison with other reconstruction methods such as the Whittaker–Shannon interpolation formula suggested by the Nyquist–Shannon sampling theorem, or such as the first-order hold or linear interpolation between sample values.
In this method, a sequence of Dirac impulses, xs(t), representing the discrete samples, x[n], is low-pass filtered to recover a continuous-time signal, x(t).
Even though this is not what a DAC does in reality, the DAC output can be modeled by applying the hypothetical sequence of dirac impulses, xs(t), to a linear, time-invariant filter with such characteristics (which, for an LTI system, are fully described by the impulse response) so that each input impulse results in the correct constant pulse in the output.
Begin by defining a continuous-time signal from the sample values, as above but using delta functions instead of rect functions:
The scaling by , which arises naturally by time-scaling the delta function, has the result that the mean value of xs(t) is equal to the mean value of the samples, so that the lowpass filter needed will have a DC gain of 1. Some authors use this scaling, while many others omit the time-scaling and the T, resulting in a low-pass filter model with a DC gain of T, and hence dependent on the units of measurement of time.
The zero-order hold is the hypothetical filter or LTI system that converts the sequence of modulated Dirac impulses xs(t)to the piecewise-constant signal (shown in Figure 2):
resulting in an effective impulse response (shown in Figure 4) of:
The effective frequency response is the continuous Fourier transform of the impulse response.
where is the (normalized) sinc function commonly used in digital signal processing.
The Laplace transform transfer function of the ZOH is found by substituting s = i 2 π f:
The fact that practical digital-to-analog converters (DAC) do not output a sequence of dirac impulses, xs(t) (that, if ideally low-pass filtered, would result in the unique underlying bandlimited signal before sampling), but instead output a sequence of rectangular pulses, xZOH(t) (a piecewise constant function), means that there is an inherent effect of the ZOH on the effective frequency response of the DAC, resulting in a mild roll-off of gain at the higher frequencies (a 3.9224 dB loss at the Nyquist frequency, corresponding to a gain of sinc(1/2) = 2/π). This drop is a consequence of the hold property of a conventional DAC, and is not due to the sample and hold that might precede a conventional analog-to-digital converter (ADC).
See also
Nyquist–Shannon sampling theorem
First-order hold
Discretization of linear state space models (assuming zero-order hold)
References
Digital signal processing
Electrical engineering
Control theory
Signal processing | Zero-order hold | [
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5,502,159 | https://en.wikipedia.org/wiki/Battle%20Angel%20Alita%3A%20Last%20Order | , also known as Battle Angel Alita: Last Order in the English translation, is a Japanese science fiction manga series created by Yukito Kishiro and published between 2000 and 2014. It is the second series of the Battle Angel Alita franchise, and a direct sequel to the original series. The series tells the story of Alita (or Gally in the original Japanese version and several other languages) continuing her quest to uncover her mysterious past. The story is continued in the third series Battle Angel Alita: Mars Chronicle. In November 2024, Yukito Kishiro stated on his personal blog that Mars Chronicle will end with chapter 56 in volume 11, and that the story will be continued in a new series with a new title.
Story
Last Order begins when Alita is resurrected by Desty Nova's nanotechnology in the floating city of Tiphares. The city's dark secrets are brutally exposed, but it turns out to be a small part of a complex world. Going into space with new and old companions alike, to look for her lost friend Lou Collins and to find out more about her forgotten past, Alita is caught up in an interplanetary struggle between the major powers of the colonized solar system. Along the way, she forms an alliance with three of the Alita Replicas who have now begun to think for themselves, an unsavory superhacker, and Nova himself when she enters the Zenith of Things Tournament (Z.O.T.T.), a fighting competition held every ten years. During the course of the story, more background about the setting of Battle Angel Alita that was not disclosed in the prior series is revealed, such as how the Earth emerged from a cataclysmic impact winter that wiped out most of the population.
Setting
Earth is a wasteland after a cataclysmic solar flare and asteroid impact, which created a long impact winter and nearly made humans extinct. Some managed to survive and, with the help of a mysterious quantum computer, rebuild civilization to what it is in Last Order. The colonization of the solar system and complex politics between the now independent colonies have left the Earth surface cut off and underdeveloped. The Scrapyard and Tiphares are found in what was once the USA (specifically the area of what is now Kansas City). Tiphares is now a big laboratory for its much more glorious sister city in space - Ketheres.
Tiphares is a futuristic utopian city that is suspended several thousand feet above the Scrapyard. Originally, Tiphares was designed to be a prototype society that was intended to test candidates for the rigors of space travel. However, after the Cam Ranh calamity, Tiphares lost communication with both the surface and its sister city Ketheres. Now, Tiphares is mainly a source of living human brains that are integrated into Ketheres' quantum computing network known as Melchizedek. The original name in Japan is Zalem.
Ketheres is Tiphares' sister city in space, connected to each other through an inertially balanced orbital elevator. It is also connected to an orbital ring, which is balanced by a similar orbital elevator and space city on the opposite side. Ketheres is somewhat of a utopian human society. However, the peace that is enjoyed there is actually a result of a system of mind-controlling computer chip brain implants and a ubiquitous system known as Unanimous. In order to be granted citizenship in Ketheres, individuals must have these implants. The original name in Japan is Jeru.
Leviathan I was once one of five interstellar colony ships, but is the only one remaining after the Cam Ranh calamity caused by Alita's past self Yoko. It's now docked in Earth's second Lagrange point, serving as a space colony. The central hub with artificial gravity houses a whole city and vast war game areas, where people made immortal by nanotechnology pay to fight for fun.
Mars, the first planet to be colonized by Earth, is currently under a four-way civil war with almost every side secretly being backed by one of the major powers of the Solar System.
Venus is being terraformed with the help of a gigantic mirror in orbit, blocking most of the sun and cooling the boiling surface. A number of orbital cities form the République Vénus (Venus Republic) and provide homes for a race of transhuman people with grotesque physiques and a liking of vile debauchery such as quasi-cannibalism. The author uses incorrect French to describe it, the correct form is République de Vénus.
Jupiter is now almost completely covered by an incomplete Dyson Sphere. It is in this sphere where the Jovians, who have given up their human bodies in exchange for cyborg box-like bodies, now live. The materials needed for the completion of the sphere come from Saturn's moons and the asteroid belt — the same moons and asteroids where Venus gets materials for its own terraforming projects, which leads to tensions between Jupiter and Venus.
is a term used to refer to humans who are infected with a retrovirus called the V-virus. The virus causes mutations in the DNA which result in the carriers exhibiting vampire-like characteristics, most notably pronounced canines and a thirst for blood. The origins of the V-virus have not been made clear, but Type-V mutants have existed throughout human history. Only in the late 20th century did advances in biology reveal that vampires were once humans who had been infected with the V-virus.
Production
Premise
Last Order continues from volume 9 of Battle Angel Alita, but diverges from the original story, as it takes place after Alita is seemingly killed by a doll bomb but ignores the events of the original ending, such as the transformation of Ketheres into a nanotechnological space flower, Alita's subsequent transformation into a flesh-and-blood human girl and her reunion with Figure.
Motivation
Kishiro has stated that he was forced to cut Battle Angel Alita short with an ending he wasn't satisfied with. After working on other projects and the manga Aqua Knight, he decided to go back to Alita's story in 2000. Originally, the story was planned to follow that of the PlayStation game Gunnm: Martian Memory, but its story is only used partially and sparingly, as Kishiro expanded and changed the story.
Publication
Last Order was on hiatus since the 100th installment due to a disagreement between Kishiro and an editor of Shueisha's Ultra Jump magazine. The editor had wanted Kishiro to refrain from using the word "psycho" in his manga dialogue. Kishiro later offered to resume the manga only if the legal department of Ultra Jump apologized to him for revising the three sections of dialogue in the new reprint of Battle Angel Alita, and Shueisha would recall the new reprinted edition and revert the revised sections to their original form. If his requirements were not met, Kishiro threatened to switch publishers to Kodansha's Evening magazine. Kishiro's requirements were apparently rejected by Shueisha and Kodansha subsequently announced that Last Order will join Evenings, starting with its 101st chapter in the 2011 8th issue, released on March 22, 2011. The manga finished on January 28, 2014.
References
Trade references
Other references
External links
Official website at Kodansha
2000 manga
Battle Angel
Biorobotics in fiction
Comics about genetic engineering
Cyberpunk anime and manga
Dystopian fiction
Exploratory engineering
Fiction about nanotechnology
Fiction about artificial intelligence
Fiction about wormholes
Fiction about cyborgs
Fiction about prosthetics
Fiction about robots
Fiction about brain–computer interface
Fiction about consciousness transfer
Fiction about the Solar System
Fiction about immortality
Fiction about megastructures
Fiction about terraforming
Kodansha manga
Seinen manga
Shueisha manga
Viz Media manga | Battle Angel Alita: Last Order | [
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