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62,375,599 | https://en.wikipedia.org/wiki/Eric%20M.%20Rains | Eric Michael Rains (born 23 August 1973) is an American mathematician specializing in coding theory and special functions, especially applications from and to noncommutative algebraic geometry.
Biography
Eric Rains was 14 when he began classes at Case Western Reserve University in 1987. He graduated with bachelor's degrees in computer science and physics and a master's degree in mathematics at age 17.
By means of a Churchill Scholarship he studied mathematics and physics at the University of Cambridge for the academic year 1991–1992, receiving a Certificate of Advanced Study in Mathematics. He received his PhD in 1995 from Harvard University with thesis Topics in Probability on Compact Lie Groups under the supervision of Persi Diaconis. From 1995 to 1996, Rains worked at the IDA's Center for Communications Research (CCR) in Princeton. From 1996 to 2002 he was a researcher for AT&T Labs. From 2002 to 2003 he returned to the CCR in Princeton. In 2003, Rains became a full professor at the University of California, Davis. From 2007-2023, Rains was a full professor at Caltech and served as the Executive Officer of the Caltech Mathematics Department from 2019 to 2022. As of Fall 2023, Rains is a professor emeritus at Caltech, per their website.
In the fall of 2006 he was a visiting professor at the University of Melbourne. He is the co-author with Gabriele Nebe and Neil J. A. Sloane of the 2006 book Self-Dual Codes and Invariant Theory.
In 2007, Rains was a plenary speaker at the Western Sectional meeting of the American Mathematical Society (AMS). In 2010 he was an invited speaker at the International Congress of Mathematicians in Hyderabad. He was elected a Fellow of the AMS in the class of 2018 for "contributions to coding theory, the theory of random matrices, the study of special functions, non-commutative geometry and number theory".
Selected publications
(This article has over 1200 citations.)
References
1973 births
Living people
20th-century American mathematicians
21st-century American mathematicians
Case Western Reserve University alumni
Alumni of the University of Cambridge
Harvard University alumni
AT&T people
Fellows of the American Mathematical Society
Combinatorialists
American mathematical analysts
American probability theorists | Eric M. Rains | [
"Mathematics"
] | 444 | [
"Combinatorialists",
"Combinatorics"
] |
62,375,753 | https://en.wikipedia.org/wiki/Biogeographia | Biogeographia: The Journal of Integrative Biogeography is a peer-reviewed open access scientific journal publishing original research and reviews in biogeography since 1970. It is published on behalf of the Italian Biogeography Society (Società Italiana di Biogeografia), using the eScholarship Publishing platform. The current editor-in-chief is Diego Fontaneto.
Abstracting and indexing
The journal is abstracted and indexed in:
Notable articles
The four most highly cited papers with more than 150 citations by the end of 2020 are:
Vigna Taglianti, A., Audisio, P. A., Biondi, M., Bologna, M. A., Carpaneto, G. M., De Biase, A., ... & Zapparoli, M.
Halffter, G.
Vigna Taglianti, A., Audisio, P. A., Belfiore, C., Biondi, M., Bologna, M. A., Carpaneto, G. M., ... & Zoia, S.
Sindaco, R., Venchi, A., Carpaneto, G. M., & Bologna, M. A.
The three most downloaded papers with more than 1000 views by the end of 2020 are:
Halffter, G.
Amori, G., & Castiglia, R.
Bianchi, C. N., & Morri, C.
References
External links
Open access journals
Ecology journals
Geography journals
Academic journals established in 1970
English-language journals | Biogeographia | [
"Environmental_science"
] | 337 | [
"Environmental science journals",
"Ecology journals"
] |
62,375,820 | https://en.wikipedia.org/wiki/Journal%20of%20Aerospace%20Engineering | The Journal of Aerospace Engineering is a peer-reviewed scientific journal published by the American Society of Civil Engineers and combines civil engineering with aerospace technology (but also incorporates other elements of civil engineering) to develop structures for space and extreme conditions. Topics of interest include aerodynamics, computational fluid dynamics, wind tunnel testing of buildings and structures, aerospace structures and materials, and more.
History
The journal has previously published under the names Journal of the Aero-Space Transport Division (1962-1966) and as the Journal of the Air Transport Division (1956-1961)
Abstracting and indexing
The journal is abstracted and indexed in Ei Compendex, Science Citation Index Expanded, ProQuest databases, Civil Engineering Database, Inspec, Scopus, and EBSCO databases.
External links
Aerospace engineering journals
American Society of Civil Engineers academic journals | Journal of Aerospace Engineering | [
"Engineering"
] | 169 | [
"Aerospace engineering journals",
"Aerospace engineering"
] |
62,376,364 | https://en.wikipedia.org/wiki/Bent%20Stumpe | Bent Stumpe (born 12 September 1938, Copenhagen, Denmark) is a Danish electronic engineer who spent most of his career at the international research laboratory CERN, Geneva, Switzerland. Stumpe built in 1972, following an idea launched by Frank Beck, a capacitive touchscreen for controlling CERN's Super Proton Synchrotron accelerator. In 1973 Beck and Stumpe published a CERN report, outlining the concept for a prototype touchscreen as well as a multi-function computer-configurable knob.
Education
Bent Stumpe was educated within the Royal Danish Air Force and obtained a certificate as a radio/radar engineer in 1959.
Career
Leaving the Air Force, Stumpe was employed from 1959–1961 at the Danish radio and television factory TO-R Radio before he was employed by CERN from 1961 until 2003. In combination with his activities at CERN, Stumpe was a consultant to the World Health Organization working on the development of an instrument for the early detection of Leprosy.
References
20th-century Danish engineers
Engineers from Copenhagen
1938 births
People associated with CERN
Living people
Electronics engineers
20th-century Danish inventors | Bent Stumpe | [
"Engineering"
] | 231 | [
"Electronics engineers",
"Electronic engineering"
] |
77,712,139 | https://en.wikipedia.org/wiki/NGC%202466 | NGC2466 is an unbarred spiral galaxy in the constellation of Volans. Its velocity with respect to the cosmic microwave background is 5428 ± 10km/s, which corresponds to a Hubble distance of . The galaxy was discovered by British astronomer John Herschel on 20 February 1835.
Supernovae
Three supernovae have been observed in NGC2466:
South African amateur astronomer Berto Monard discovered SN2003gh (typeIa, mag.15.7) on 29 June 2003.
ASASSN-14dd (typeIbn, mag.15.6) was discovered by the All Sky Automated Survey for SuperNovae on 24 June 2014.
SN2016iye (typeIIb, mag.17.4) was discovered by Stuart Parker on 19 December 2016.
See also
List of NGC objects (2001–3000)
References
External links
2466
021714
059-018
07456-7117
Volans
18350220
Discoveries by John Herschel
Unbarred spiral galaxies | NGC 2466 | [
"Astronomy"
] | 212 | [
"Volans",
"Constellations"
] |
77,712,145 | https://en.wikipedia.org/wiki/Cyclocybe%20erebia | Cyclocybe erebia, also known as the dark fieldcap, or sometimes Agrocybe erebia, is a species of brown-spored agaric with a wide distribution. It occurs in the Americas, Europe, and parts of Oceania. It is a member of the family Strophariaceae.
Description
Appearance
The color of the cap can range from a light brown color to a darker brown color. When wet, it is slimy, or viscid. The cap can range from , with younger caps being very round. The edge of the cap is often frilled or wrinkly, and more lightly colored. Decurrent gills are present underneath the cap. They are whitish at first, but they become brown with maturity. The stipe is whitish, browning with age, long, and thick. The flesh does not stain.
When young, a partial veil is present, covering the hymenium. It later separates from the margin, sometimes leaving behind a white ring.
Microscopic features
The spores measure , and are ellipsoid or subellipsoid, often with a snout-like end, and are brown or yellow-brown.
The basidia are 2-sterigmate.
Taxonomy
Cyclocybe erebia was once considered to be in the genus Agrocybe, but recent DNA sequencing has shown that it is not, instead placing it in Cyclocybe.
References
Edible fungi
Fungi in cultivation
Strophariaceae
Fungus species | Cyclocybe erebia | [
"Biology"
] | 308 | [
"Fungi",
"Fungus species"
] |
77,712,380 | https://en.wikipedia.org/wiki/Minimum%20mean%20weight%20cycle | In graph theory, a minimum mean weight cycle is a cycle whose average weight (total weight divided by length) is smallest among all cycles in the graph. An analogous problem is the maximum mean weight cycle. These problems have applications to embedded systems and logic chip design.
Definitions
Let G = (V,E) be a directed graph in which each edge has a weight (positive or negative). The weight of any path or cycle p = (e1,...,ek), is the sum of weights of the edges: w(p) = w(e1) + ... + w(ek). The mean weight of p is the weight of p divided by the number of edges in it: w(p)/len(p).
The minimum cycle mean weight in G is the minimum, over all directed cycles p in G, of w(p)/len(p). A minimum mean weight cycle is any cycle with the minimum mean weight.
Algorithms
Lawler presented an algorithm for computing a minimum mean weight cycle using O(log |V|) calls to an algorithm for solving the negative cycle problem. There exists such an algorithm that runs in time O(|V||E|), so the total runtime of Lawler's algorithm is O(|E||V|log |V|).
Karp's algorithm
Karp presented a characterization of the minimum cycle mean weight, and presented an algorithm that runs in time O(|V||E|). An analogous algorithm can be used for finding a maximum mean weight cycle.
Let G be any directed graph, and let s be a fixed vertex in G. For every nonnegative integer k and every vertex v in G, define Hk(v) as the maximum cost of a path of length k from s to v; if no such path exists, then Hk(v) = minus infinity.
The main lemma says that the maximum mean cycle weight of G equals(*) Proof. It is sufficient to prove the lemma for the case in which the maximum mean cycle weight equals 0. This is because adding a constant weight to each edge adds the same constant both to the maximum mean cycle cost and to the expression in (*).
Suppose the maximum mean cycle weight is 0. Then there is a cycle with cost exactly 0, but no cycles with a positive cost.
We first prove that (*) is at most 0. As G has no positive-cost cycles, for every node v, there is a maximum-cost path of length smaller than n from s to v. Let kv be the length of this maximum-cost path. Then Hkv(v) >= Hn(v), so the expression inside the min in (*) is at most 0 when k = kv. As kv <= n-1, the minimum in (*) is at most 0. As this holds for every node v, the maximum in (*) is at most 0 too.
We now prove that (*) is at least 0. G has a zero-cost cycle; let w be some node in that cycle. Let P0 be a maximum-cost path from s to w. For every t >= 1, let Pt be a concatenation of P0 with t copies of the cycle; as the cost of Pt equals the cost of P0, it is also a maximum-cost path from s to w. Every prefix of a maximum-cost path is also a maximum-cost path from s to its endpoint. When t is sufficiently large, Pt has a prefix of length n; it is a maximum-cost path from s to some node w'. Then Hn(w') >= Hk(w') for all k, so the expression inside the min in (*) is at least 0 for all k, so the minimum in (*) is at least 0. Taking v=w' in the maximum shows that the maximum in (*) is at least 0 too.
Therefore, when the maximum mean cycle cost is 0, (*) equals 0, which is sufficient to complete the proof.
It is possible to compute Hk using dynamic programming in time O(|E||V|); then it is possible to find the maximum mean cycle weight using (*). The cycle itself can be found as follows:
Find the maximizing v and the minimizing k in (*).
As the outcome for this v and this k is finite, both Hn(v) and Hk(v) are finite. This means that there exists a maximum-weight path of length n from s to v, and a maximum-weight path of length k from s to v. Therefore, the path of length n contains a cycle of length n-k; this is the maximum mean weight cycle.
Chaturvedi and McConnell identified an error in Karp's algorithm for constructing a cycle attaining the minimum mean weight. They presented a corrected algorithm.
Newer algorithms
Dasdan and Gupta study maximum mean weight cycle, and present an algorithm that is provably always faster than Karp's algorithm.
Albrecht, Korte, Schietke and Vygen relate the problem of maximum mean weight cycle to the minimum balance problem: find a potential function such that the "slacks" of all edges are optimally balanced. Both problems can be solved by a parametric shortest path algorithm. They show that parametric shortest path can be used for solving more general variants of these problems, with constraints that are relevant to optimizing the clock schedule of a logic chip.
See also
Negative cycle
References
Graph theory objects | Minimum mean weight cycle | [
"Mathematics"
] | 1,164 | [
"Mathematical relations",
"Graph theory",
"Graph theory objects"
] |
77,712,769 | https://en.wikipedia.org/wiki/CWISE%20J1249%2B3621 | CWISE J1249+362 (CWISE J124909.08+362116.0) is a low-mass hypervelocity star about 408 light-years distant in the constellation Canes Venatici. It has an L spectral type and is either a low-mass red dwarf or a high-mass brown dwarf. It has a speed of 456±27 km/s in the galactic rest frame, near the local escape velocity of the Milky Way.
Discovery
CWISE J1249+362 was first identified in the Backyard Worlds project by the citizen scientists Tom Bickle, Martin Kabatnik, and Austin Rothermich (now astronomer). The astronomers of the project observed the object because its motion and distance suggested a high velocity. The astronomers used NIRES on the Keck Observatory to take a spectrum of the object. The researchers also identify the esdL1 dwarf ULAS J231949.36+044559.5 as an additional candidate hypervelocity star (vtan≈513 km/s) with a low mass.
Physical properties and origin
The object has a distance of 125±8 parsec from the sun and its spectrum is sdL1, with sd noting that it is a cool subdwarf. The star has a high tangential velocity of 524±33 km/s and a high radial velocity of −103±10 km/s. In the galactic rest frame this translates into a speed of 456±27 km/s. It has an estimated mass between 83 and 88 , which would make it a low-mass star near the hydrogen-burning limit. The researchers say that the object does have a 10% probability to be a high-mass brown dwarf because the evolutionary model does not account for potential systematic biases for old low-temperature sources.
The researchers explore different scenarios which could have caused the high velocity of CWISE J1249+362. One possibility is that it originates from the Galactic Center. The object is currently moving towards the Galactic Center, so it could be on its return pass. This is however only possible if it is bound to the Milky Way. Another possibility is that it was ejected during a type Ia supernova. In this scenario CWISE J1249+362 would have been in a tight binary with a massive white dwarf, which would have involved mass transfer in a cataclysmic variable star. The predicted ejection speed for this scenario agrees with the speed of CWISE J1249+362. Two other possibilities are that it originates from a dynamical ejection from a globular cluster or ejection from a nearby dwarf galaxy. There are however no globular clusters in the past position of this object. It is unlikely that CWISE J1249+362 is an extragalactic star, because its motion is confined within the galactic plane, which makes an origin within the Milky Way more likely.
More research that involves a direct measurement of its parallax and additional optical and infrared spectra are needed to narrow down its origin. If it originated in a type Ia supernova, its atmosphere could for example be enriched in heavy elements, particularly in nickel.
References
External links
press-release by NASA
press-release by UC San Diego
press-release by the W.M. Keck Observatory
Artist's simulation of the ejection of CWISE J1249+362 in a type Ia supernova on YouTube
Artist's simulation of the ejection of CWISE J1249+362 during a close encounter with a binary black hole on vimeo
Hypervelocity stars
L-type stars
L-type brown dwarfs
Canes Venatici | CWISE J1249+3621 | [
"Astronomy"
] | 765 | [
"Canes Venatici",
"Constellations"
] |
77,712,898 | https://en.wikipedia.org/wiki/Agriculture%20in%20ants | Agriculture and domestication are practices undertaken by certain ant species and colonies. These ants use agricultural methods and are known as one of the few animal groups, along with Homo sapiens, to have achieved the level of eusociality necessary to practice agriculture. It is estimated that ants began this practice at least 50 million years ago. The domestication of plant, fungus, and animal species by ants is well documented. For some ant species or groups, this is an activity essential to their survival, particularly in a symbiotic relationship with the cultivated species, especially plants or fungi. Some plants require the presence of ants for their survival and offer benefits to the ants in return, creating a mutualistic relationship between their species. The agricultural practices of ants vary widely from one species to another, but they can engage in creating compost necessary for plant growth, fighting pathogens that affect cultivated species, destroying invasive species that threaten their crops, creating "ant gardens" of up to fifty different plants, optimizing crops by adapting to the solar cycle and other natural cycles, or generally engaging in grooming activities. In some cases, it is believed that ants can achieve productivity levels similar to the early stages of human agriculture. Ants also domesticate numerous animal species, especially aphids and Lepidoptera. Discovered only in 2016, ant farming and agriculture with plants is a rapidly evolving field of discoveries.
As of 2022, it is estimated that ants assist in the dispersal of seeds for over 11,000 plant species, are in mutualistic relationships with at least 700 plant species, and engage in purely agricultural processes with hundreds of others. Regarding domesticated animals, more than 1,000 of the 4,000 known species of aphids and around 500 species of Lepidoptera are affected by ant domestication.
Terminology
The use of the term "agriculture", which may not be entirely appropriate for mutualistic relationships—particularly in cases where a colony is hosted by a plant, such as a tree, in exchange for protection and aid in its survival and growth—is well documented in the scientific literature for processes where ants create crops and directly cultivate plants or fungi. The use of the term "domestication" is also well established when ant domestication has led to specific evolutionary changes in the species involved.
Causes and prevalence
Causes
It remains difficult to determine the causes that led different ant species to adopt these behaviors over millions of years of evolution, due to the vast diversity of behaviors depending on the location, the plants, fungi, and animals involved, as well as the great diversity of ant species. However, numerous studies focus particularly on these evolutionary developments, especially in a comparative framework with the human species, to identify commonalities and differences between the two processes. Overall, it seems that leafcutter ant species that developed agricultural practices involving fungi began doing so at least 65-55 million years ago and may have been the first to have engaged in such behavior, though it's not certain. The common ancestor of these species is dated to -65/-55 million years ago. It seems, according to research dating from 2017, that this change occurred in dry habitats, notably in South America.
Prevalence
As with the causes that led to such behavioral evolution in certain ants, it remains difficult to assess the overall prevalence of these behaviors. As of 2022, it is estimated that ants assist in the dispersal of seeds for over 11,000 plant species, are in mutualistic relationships with at least 700 plant species, and engage in purely agricultural processes with hundreds of others. Regarding domesticated animals, more than 1,000 of the 4,000 known species of aphids and around 500 species of Lepidoptera are affected by ant domestication. In comparison, Homo sapiens engages in farming and agriculture with '260 plant, 470 animal and 100 mushroom-forming fungal species'. Plant farming by ants was only discovered in 2016, making it a very young and rapidly evolving field of study. However, these phenomena appear to involve hundreds of different ant species out of the approximately 13,000 species discovered to date. In 2022, it was believed that approximately 37 various ant species engaged in true plant cultivation, without considering domestication and fungiculture.
Processes
Ants, depending on the species, engage in a wide range of behaviors and practices. Some species, such as leafcutter ants, form symbiotic relationships with certain fungi. In these cases, the queen of a future colony often carries with her a clone of the fungus from her original colony, which her new colony will cultivate and tend to in order to ensure their survival and food supply. They attack pathogens that affect these fungi, defend them against potential threats, and generally engage in grooming to maintain the health of the fungi. This allowed leafcutter ants to become the dominant herbivore species in South America and made them able to create massive ant colonies, containing millions of workers and thousands of ant rooms. The agricultural practices of ants vary widely from one species to another, but they can engage in creating compost necessary for plant growth, fighting pathogens that affect cultivated species, destroying invasive species that threaten their crops, creating "ant gardens" of up to fifty different plants, optimizing crops by adapting to the solar cycle and other natural cycles, or generally engaging in grooming activities. In some cases, it is believed that ants can achieve productivity levels similar to the early stages of human agriculture. They are also known to have, with Homo Sapiens, and a very few number of other animal groups, managed domestication of other animals, in that case, aphids and Lepidoptera.
Some ant species, such as Philidris nagasau, were proven recently to create large plant gardens containing dozens of different plants, that they use and tend to. This gave them the ability to develop very large colonies and they enjoy results similar to the beginnings of human agriculture, that humans were able to achieve during the Neolithic period.
References
Agronomy
Food industry
Ants
Symbiosis
Ethology
Behavior | Agriculture in ants | [
"Biology"
] | 1,222 | [
"Behavior",
"Symbiosis",
"Biological interactions",
"Behavioural sciences",
"Ethology"
] |
77,713,191 | https://en.wikipedia.org/wiki/NGC%201101 | NGC 1101 is a lenticular galaxy in the Cetus constellation, and is an estimated 331 million light-years away from Earth. It was discovered on 22 November 1876 by French astronomer Edouard Stephan, who described it as "very faint, small, round with a brighter middle".
NGC 1101 contains a flat-spectrum radio source and it has a HI line width.
To date, a non-redshift measurement gives the galaxy a distance of 81,700 megaparsecs (Mpc) or equal to ~266 million light-years. This value is just outside the Hubble distance values. According to NASA/IPAC database, the diameter of NGC 1101 is calculated to be around 41.3 kiloparsecs (~135,000 light-years) if the Hubble distance were to calculate it.
See also
List of NGC objects (1001–2000)
References
External links
1101
010613
Lenticular galaxies
02278
+01-08-003
Astronomical objects discovered in 1876
Discoveries by Édouard Stephan
Cetus | NGC 1101 | [
"Astronomy"
] | 216 | [
"Cetus",
"Constellations"
] |
77,714,151 | https://en.wikipedia.org/wiki/Cheyava%20Falls | Cheyava Falls is a rock discovered on Mars by NASA's Perseverance rover during its exploration of the Jezero Crater. This rock, named after a Grand Canyon waterfall, has drawn significant attention due to its potential as an indicator of ancient life on Mars. The rover's instruments detected organic compounds within the rock, which are essential for all known life. According to NASA, Cheyava Falls "possesses qualities that fit the definition of a possible indicator of ancient life".
"Cheyava Falls" is characterized by large white calcium sulfate veins and bands of reddish material, indicative of hematite, a mineral that gives Mars its rusty color. The veins are "filled with millimeter-size crystals of olivine". The rock features millimeter-sized off-white splotches surrounded by black material, resembling "leopard spots." These spots contain iron and phosphate, elements often associated with microbial life. According to a seven-step scale called Confidence of Life Detection (CoLD) used by NASA astrobiologists, the rock is on Step One, "Detect possible signal".
The rock's composition suggests it was once exposed to water. However, there are alternative, non-biological explanations for its features. The rover has analyzed the rock using various instruments but its team concludes that a definitive understanding will require returning the sample to Earth for more in-depth study.
The "arrowhead-shaped rock" was found at the northern edge of Neretva Vallis area, on July 18, 2024, and is 1 meter by 0.6 meters. On July 21, Perseverance took a sample of the rock that became its 22nd core sample that can be delivered to Earth by a future mission. The rover made a "selfie" with a rock on July 23.
Gallery
References
Mars 2020
Rocks on Mars
Astrobiology | Cheyava Falls | [
"Astronomy",
"Biology"
] | 378 | [
"Origin of life",
"Speculative evolution",
"Astrobiology",
"Biological hypotheses",
"Astronomical sub-disciplines"
] |
77,715,265 | https://en.wikipedia.org/wiki/Pixel%20stealing%20attack | In cybersecurity, pixel stealing attacks are a group of timing side-channel attacks that allow cross-origin websites to infer how a particular pixel is displayed to the user.
History
One of the earliest known instances of a pixel-stealing attack was described by Paul Stone in a white paper presented at the Black Hat Briefings conference in 2013. Stone's approach exploited a quirk in how browsers rendered images encoded in the SVG format. SVG images support various features, including the ability to apply SVG filters that applies transform image content. Stone discovered that by measuring the time it took for a browser to render a morphological filter over a known set of pixels and then comparing this with the time taken to render the same filter over a pixel from an unknown website, he could infer the color of the pixels. This allowed him to build a grayscale image of the other website which could be then used to leak information about the website.
References
Client-side web security exploits | Pixel stealing attack | [
"Technology"
] | 201 | [
"Computer security stubs",
"Computing stubs"
] |
77,715,393 | https://en.wikipedia.org/wiki/Halen%20M%C3%B4n | Halen Môn is a salt-producing company in Anglesey, Wales on the bank of the Menai Strait. Its sea salt, a fleur de sel, has been given Protected Designation of Origin status. It was founded in 1997 by Alison and David Lea-Wilson, who also started the Anglesey Sea Zoo.
See also
List of edible salts
List of United Kingdom food and drink products with protected status
References
Salt production
Food and drink companies of Wales
Anglesey
Companies of Wales
Economy of Anglesey
Organisations based in Anglesey
1997 establishments in Wales | Halen Môn | [
"Chemistry"
] | 111 | [
"Salt production",
"Salts"
] |
77,715,797 | https://en.wikipedia.org/wiki/Bob%20Hearn | Robert Aubrey Hearn is an American ultramarathon runner, computer scientist, and recreational mathematician.
Computer science and recreational mathematics
Hearn is originally from Oklahoma; as a student at Memorial High School (Tulsa, Oklahoma) in the early 1980s, he was passionate about solving the Rubik's Cube. He is a 1987 alumnus of Rice University; at Rice, he was a member of the Marching Owl Band and of Rice's third-place-winning team in the 1986 International Collegiate Programming Contest.
Hearn was hired from Rice by StyleWare, a developer of Apple II software. With another Rice student and ICPC contestant, Jeff Erickson, he wrote TopDraw, a black-and-white bitmap drawing program that was purchased by Beagle Bros and became BeagleDraw. StyleWare was purchased by Claris, and
with Scott Holdaway, Hearn became one of the two original developers of ClarisWorks, a popular integrated office suite for Apple Macintosh computers. He, Holdaway, and several other ClarisWorks developers founded Gobe Software in 1997.
He later became a doctoral student of Erik Demaine at the Massachusetts Institute of Technology, co-advised by Gerald Jay Sussman. His 2006 dissertation invented nondeterministic constraint logic and used it to characterize the computational complexity of many games, puzzles, and reconfiguration problems. He and Demaine turned his dissertation into the 2009 book Games, Puzzles, and Computation.
He is a member of the board of directors for Gathering 4 Gardner.
Running
Hearn first began competing in ultra-marathons when he was 42, and has set many US records for his age classes. He was honored in 2022 by a Tennessee House of Representatives Bill that named him "King of the Road" for winning the 2021 Last Annual Vol State Road Race, a race, of which passed through Tennessee. In 2023, USA Track & Field named him as their male masters ultrarunner of the year.
Personal life
Hearn is married to Elizabeth H. Hearn, an independent geophysicist, former professor at the University of British Columbia, and program director at the National Science Foundation.
References
External links
The puzzle of running, Hearn's running blog
Bob Hearn Race Results, Ultra Running Magazine
Year of birth missing (living people)
Living people
People from Tulsa, Oklahoma
American male ultramarathon runners
American computer scientists
American mathematicians
Recreational mathematicians
Rice University alumni
Massachusetts Institute of Technology alumni | Bob Hearn | [
"Mathematics"
] | 501 | [
"Recreational mathematics",
"Recreational mathematicians"
] |
77,717,243 | https://en.wikipedia.org/wiki/N1-Acetyl-N2-formyl-5-methoxykynuramine | {{DISPLAYTITLE:N1-Acetyl-N2-formyl-5-methoxykynuramine}}
N1-Acetyl-N2-formyl-5-methoxykynuramine (AMFK) is a metabolite of melatonin and an antioxidant.
References
Antioxidants
Metabolites
Acetamides
Methoxy compounds
Formamides
Benzaldehydes | N1-Acetyl-N2-formyl-5-methoxykynuramine | [
"Chemistry"
] | 97 | [
"Metabolites",
"Metabolism"
] |
77,718,908 | https://en.wikipedia.org/wiki/Sakura%20%28text%20editor%29 | Sakura Editor is a free and open-source Japanese text editor for Microsoft Windows.
History
Sakura Editor was started by Take (), the original author, around 1998 and the source code was made public around 2000. Development was carried out on SourceForge until May 2018, then it was moved to GitHub in June of the same year.
Features
Sakura Editor uses cream color as the default background. It supports keyword highlighting, outline analysis, and completion. In addition, it has basic functions such as multiple encodings, grep, and macros. It notably supports handling documents with mixed line breaks. It also supports various character encodings such as Shift_JIS, ISO-2022-JP, EUC-JP, UTF-16, UTF-8, and UTF-7.
There are currently official 32-bit and alpha 64-bit versions.
License
Since v2.4.0, it has been distributed under the zlib license.
References
External links
SakuraEditorWiki
Windows text editors
Free and open-source software
Free software programmed in C++
HTML editors
1999 software | Sakura (text editor) | [
"Technology"
] | 227 | [
"Computing stubs",
"Software stubs"
] |
77,718,925 | https://en.wikipedia.org/wiki/Pueblo%20religion | Pueblo religion (or Katsina religion) is the religion of the Puebloans, a group of Native American tribes in the Southwestern United States. It is deeply intertwined with their culture and daily life. The Puebloans practice a spirituality focused on maintaining balance between the physical and spiritual worlds, which they believe is essential for bringing rain, ensuring good crops, and promoting well-being.
Pueblo religion is predominantly practiced among Puebloans, who today live in settlements such as Pueblos, Taos, San Ildefonso, Acoma, Zuni, and the Hopi villages.
Pueblo religion is holistic, with every aspect of daily life—from farming to sleep—being viewed as a form of worship.
Background
Puebloan societies incorporate elements of three major cultures that dominated the Southwestern United States before European contact: the Mogollon culture, whose adherents occupied an area near the Gila Wilderness; the Hohokam culture; and the Ancestral Pueblo culture, who occupied the Chaco Canyon and Mesa Verde regions in the Four Corners area.
The Ancestral Puebloan culture is known for the stone and earth dwellings its people built along cliff walls, particularly during the Pueblo II and Pueblo III eras, from about 900 to 1350 CE. The best-preserved examples of these dwellings are now protected within the United States' national parks, such as Navajo National Monument, Chaco Culture National Historical Park, Mesa Verde National Park, Canyons of the Ancients National Monument, Aztec Ruins National Monument, Bandelier National Monument, Hovenweep National Monument, and Canyon de Chelly National Monument.
Before European contact, there were around 70 or more Pueblo villages, some of which were already centuries old when the Spanish arrived. Oraibi, now part of the Hopi Reservation in Arizona, and Acoma in New Mexico are among the oldest continuously occupied settlements in the United States, dating to around 1100 CE.
History
Origins
The origins of the religion are debated, with theories suggesting influences from Mexican traditions like Casas Grandes (1130–1350), the Mimbres culture, known for its figurative pottery, or a combination in which the Mimbres culture indirectly influenced Casas Grandes, leading to the development of the Katsina tradition.
The Pueblo religion likely emerged in the late 13th to early 14th centuries when migrants from the Four Corners region settled in the upper Colorado Valley and integrated with the indigenous Mogollon or western Pueblo people.
Conflict and Decline
Spanish soldiers first arrived on Pueblo lands in 1540, with western Pueblo communities protected by the remote Colorado Plateau, while the more accessible eastern Pueblo settlements suffered harsh treatment.
Spain's attempts to suppress Pueblo religion and replace it with Catholicism grew increasingly aggressive, leading to resistance by the Puebloans. However, the Catholic Church has had a lasting influence on the lives of Pueblo Indians. Today, about 90% of Pueblo Indians identify as Catholic. Some Puebloans practice a syncretic "Pueblo Christianity," blending Catholic and Pueblo religious practices.
Deities
The Pueblo religion includes more than 500 divine and ancestral spirits. These spirits are believed to interact with humans during rituals, where performers, adorned in Kachina masks and attire, are thought to transform into the spirits they represent.
Kachina
Central to Pueblo religion is the concept of the Kachina (also called Katsina), a spirit being in the religious beliefs of the Pueblo people. These beings, once believed to visit Pueblo villages, are now honored through masked dances and rituals in which Pueblo people embody the Kachinas. Kachinas have the power to take the form of clouds and bring rain for agricultural fields. They also have the ability to heal or cause disease.
Prayer
Pueblo prayer included substances as well as words; one common prayer material was ground-up maizewhite cornmeal. A man might bless his son, or some land, or the town by sprinkling a handful of meal as he uttered a blessing. After the 1692 re-conquest, the Spanish were prevented from entering one town when they were met by a handful of men who uttered imprecations and cast a single pinch of a sacred substance.
Ceremonies
Kiva
The Pueblo religious system also features underground ceremony called Kiva. A kiva is a space used by Puebloans for rites and political meetings, many of them associated with the kachina belief system. Among the modern Hopi and most other Pueblo peoples, "kiva" means a large room that is circular and underground, and used for spiritual ceremonies and a place of worship.
Great Kiva
Great kivas are larger, deeper, and distinct from Chaco-style kivas, with walls extending above the landscape, while Chaco-style kivas remain flush with it. Unlike Chaco-style kivas, which are incorporated into great houses, great kivas are separate, often feature encircling benches, and include floor vaults likely used as foot drums for ceremonies.
Katsina dance
Religious ceremonies of the Pueblo religion usually feature traditional and sacred dances. the dancers are called "Katsinam dancers". they are held outdoors in the large common areas and courtyards, which are accompanied by singing and drumming. Unlike kiva ceremonies, traditional dances may be open to non-Puebloans. Traditional dances are considered a form of prayer, and strict rules of conduct apply to those who wish to attend one (e.g. no clapping or walking across the dance area or between the dancers, singers, or drummers). Katsina dances are practiced exclusively by the Pueblo people of the southwestern United States, who currently live in around 25 villages across Arizona and New Mexico, divided into linguistic groups such as Zuni, Keres, Towa, Tewa, Tiwa, and historically, Tompiro and Piro.
References
Native American religion
Hopi mythology
Creation myths | Pueblo religion | [
"Astronomy"
] | 1,178 | [
"Cosmogony",
"Creation myths"
] |
77,719,490 | https://en.wikipedia.org/wiki/Rim%20Jong%20Hyok | Rim Jong Hyok () is a North Korean hacker and a member of the Andariel, a hacker group controlled by the Reconnaissance General Bureau.
Life
Nothing is known about his early life except that he was born in North Korea.
Hacking career
In 2021, Hyok funneled money, the money being bitcoin, from ransomware programs that were used against both U.S. and South Korean targets, specifically the attacking of computer and server systems in American hospitals and healthcare institutions and other systems affiliated with United States affiliated organizations like NASA and the Department of Justice, in order to continue funding these operations. The attacks against the health care institutions caused many classified personal documents, including medical records, being locked and possibly stolen. Hospitals were affected in Arkansas, Colorado, Connecticut, Florida, and Kansas. He also illegally accessed computers affiliated with the U.S. military, some being on bases, and stole classified documents belonging to the United States. In 2022, he was caught stealing data for classified military aircraft.
In July 2024, Hyok was officially indicted on conspiracy to launder money by a Kansas Grand Jury with Hyok not having an attorney during the indictment. In total, he laundered hundreds of thousands of money to fund operations for North Korean hacker groups. The United States Department of State offered USD$10 million in more information that leads to the arrest of Hyok.
References
Living people
North Korean people
Hackers
Fugitives wanted by the United States
Year of birth missing (living people) | Rim Jong Hyok | [
"Technology"
] | 309 | [
"Lists of people in STEM fields",
"Hackers"
] |
77,720,228 | https://en.wikipedia.org/wiki/Charles%20Walcott%20%28ethologist%29 | Charles Walcott (1934-) is an ethologist and Professor Emeritus at Cornell University. He studied how spiders catch prey, as well as how pigeons home.
Early life and education
Walcott obtained his A.B. in biology in 1956 and his Ph.D. in zoology from Cornell in 1959.
Career
He worked as an assistant professor at Harvard from 1961-1965 and then at Tufts until 1967. He then worked at SUNY Stony Brook until 1981. He returned to Cornell as full professor and the Director of the Ornithology lab in 1981, where he stayed until his retirement in 2016. He served as Dean of the University Faculty from 2003-2008. He was elected as a fellow to the AAAS in 2018.
He also worked as a producer of nature TV shows for children for WGBH.
References
Ethologists
American biologists
Cornell University alumni
Cornell University faculty
1934 births
American ornithologists | Charles Walcott (ethologist) | [
"Biology"
] | 188 | [
"Ethology",
"Behavior",
"Ethologists"
] |
77,723,569 | https://en.wikipedia.org/wiki/Greg%20Landsberg | Greg Landsberg is an American particle physicist. He is the Thomas J. Watson Sr. Professor of Physics at Brown University.
Biography
Landsberg obtained his doctor of philosophy from SUNY Stony Brook in 1994, supervized by Paul Grannis. He worked at the DØ experiment at Fermilab during and after his PhD. He entered Brown University's faculty in 1998.
In 2001 Landsberg became a Alfred P. Sloan Fellow. In the same year, he wrote with Savas Dimopoulos about the generation of minuscule blackholes in the Large Hadron Collider (LHC). Landsberg was also the Deputy Physics Coordinator of DØ, before he led the Brown team to join the CMS Experiment at CERN in 2004.
In 2009 he was elected a Fellow of the American Physical Society, see list and announcement by his department.
In 2010, Landsberg proposed a theory in which the universe's dimensions grow as it expands. He also participated in the search of the Higgs Boson. From 2012 to 2013, he was the Physics Coordinator at the CMS Experiment. He became the Thomas J. Watson Sr. Professor of Physics at Brown University in 2014.
References
Brown University faculty
Sloan Research Fellows
21st-century American physicists
Particle physicists
Stony Brook University alumni
Year of birth missing (living people)
Living people | Greg Landsberg | [
"Physics"
] | 272 | [
"Particle physicists",
"Particle physics"
] |
67,578,857 | https://en.wikipedia.org/wiki/Laylight | As an element of architecture, a laylight is a glazed panel usually set flush with the ceiling for the purpose of admitting natural or artificial light. Laylights typically utilize stained glass or lenses in their glazing. A laylight differs from a glazed (or closed) skylight in that a skylight functions as a roof window or aperture, while a laylight is flush with the ceiling of an interior space. When paired with a roof lantern or skylight on a sloped roof, a laylight functions as an interior light diffuser. Before the advent of electric lighting, laylights allowed transmission of light between floors in larger buildings, and were not always paired with skylights.
See also
Daylighting
Pavement light
Prism lighting
References
Lighting
Windows
Energy-saving lighting
Solar architecture | Laylight | [
"Engineering"
] | 156 | [
"Architecture stubs",
"Architecture"
] |
67,578,931 | https://en.wikipedia.org/wiki/Allomothering%20in%20humans | Allomothering, or allomaternal care, is parental care provided by group members other than the genetic mother. This is a common feature of many cooperative breeding species, including some mammal, bird and insect species. Allomothering in humans is universal, but the members who participate in allomothering vary from culture to culture. Common allomothers are grandmothers, older siblings, extended family members, members of religious communities and ritual kin (such as godparents).
The life history strategy of humans involves a long period of dependency, termed "secondary altriciailty" by Adolf Portmann, which should result in longer interbirth intervals. However, compared to other primates, humans have short interbirth intervals resulting in numerous overlapping dependents all without an increase in child mortality. Allomothering explains how humans can have children spaced only a few years apart and manage to raise multiple children at once. Food provisioning, help with childcare and investment in the child's learning can be provided by members of the community to help ease the mother's investment. Allomothering participants and specific helping behavior varies widely from group to group.
Theory
Cooperative breeding is a reproductive strategy that has been observed in birds, insects, and mammals. In cooperative breeding, parents receive support in childrearing from other members of the community. The parental support of helpers other than parents is known as allomaternal care (from the perspective of the mother, in species where both maternity and paternity is known it is often referred to alloparenting/allopaternal care) and can be carried out by kin and non-kin members of the community. Cooperative breeding is often seen to arise in monogamous mating systems with high coefficients of relatedness between group members and where females give birth to multiple offspring. The presence of allomothers is associated with reductions in interbirth intervals, increases in litter size, higher annual rates of survival. Cooperative breeding reduces the investment necessary for the parents of an offspring allowing the freed-up resources to be directed towards producing more offspring. Studies among meerkats suggest that while helpers incur great short term costs, long term costs are minimal or non-existent. Help by allomothers can be conditional upon health at the onset of the reproductive cycle, such as weight in meerkats, and helpers are able to modify their behavior to offset some of the short-term costs, i.e., increased time spent foraging and alternate breeding cycles in which they help. Cockburn shows that helpers among birds may benefit from increased numbers of non-descendant kin, increased access to territory and resources, increased access to mating options, increases in social status and longer time to acquire skills.
Cooperative breeding is common in many mammal species, but the type of care can vary greatly. Isler and van Shaik's survey allomothering in placental mammals found that 46% engaged in no help, 10% only provided protection, 3% provided only allonursing, 24% provided all forms of help other than provisioning and 16% provided complete help, including provisioning (see Figure 1, pg. 55). Allomaternal help with provisioning was most common among members of Carnivora and Primates. The study also looked at correlations of allomaternal care and brain size, finding mixed results among many of the orders, however among Carnivora there was a correlation between male help and brain size and in Primates there was a correlation between allonursing and brain size. It has also been demonstrated that increases in allomothering among chimps is associated with a reduction in lactation efforts and shorter weaning times. Hrdy argues that in order for cooperative breeding to occur, the underlying neural circuitry must be present in both sexes as well as pre- and post-reproductive aged individuals. This neurocircuitry includes a tendency to be attracted to, hold and protect infants, all of which are common among primates in various degrees.
Evolution among humans
Humans produce offspring that develop slowly and are incapable of moving or retrieving food for a lengthy period after birth. In animals that have infant altriciality and extended development, interbirth intervals are often longer to allow the mother to fully invest in one offspring before conceiving another. However, humans do not follow the pattern seen in other apes: human life history features relatively short interbirth intervals resulting in child-rearing costs that the mother alone cannot provide. Allomaternal care is a universal feature of human reproduction that helps provide additional childcare and other resources for the parents. While short interbirth intervals can negatively impact child outcomes, increasing the risk of child mortality, allomaternal care can reduce these negative outcomes while allowing interbirth intervals to remain short. When compared to other living primates, humans have short interbirth intervals (IBI), averaging 3.1 years in natural fertility populations, and total fertility rates (TFR) of 6.1 offspring versus interbirth intervals and total fertility rates for chimpanzees (IBI = 5.5, TFR = 2), gorillas (IBI = 3.9, TFR = 3) and orangutans (IBI = 9.2). Humans also have a unique period in their prolonged dependency, childhood, which allows for increased development and social learning.
The emergence of cooperative breeding in early hominins may explain several key life history traits such as larger brains and our demographic success around the globe. Isler and van Schaik analyzed life history traits such as first age of reproduction and interbirth intervals in primates and applied the resulting data to ancestral hominins and determined that without cooperative breeding the first age of reproduction for Australopithecus afarensis would be around 12.6 years and for Qafzeh Homo sapiens around 26.1 years. The predicted interbirth intervals would range from 6 to 8.4 years. Assuming some form or allomaternal care as early as A. afarensis, first age of reproduction comes down to 10.9 years and interbirth intervals are reduced to approximately 3.4 years. For Qafzeh H. sapiens, first age of reproduction is reduced to 22.6 years and interbirth intervals are around 4.7 years. Based on their study, Isler and van Shaik conclude that a change in lifestyle resulting in substantial increases in allomothering occurred early in the Homo genus. This implies that cooperative breeding has been an important part of human history for nearly two million years.
Demographic reconstructions of hunter-gatherer populations in the Pleistocene attempt to analyze the probability of having allomothers in a community and rely on assumptions about residential patterns in early humans. Kurland and Sparks (pers. comm. In Hrdy, 2006) provide estimates of several relatives' presence assuming different mortality rates. Under low mortality rates, the chance of primipara, a woman giving birth to her first child, having her mother around is around 50% and under high mortality rates the chance drops to 25%. The chance of having an older sibling around is much higher, as are the chances of having cousins. While this indicates that a new mother would have a least some close kin nearby to help with childcare, residential patterns may change these likelihoods. If humans were majority patrilocal, where males remain in natal groups and females disperse, we would expect lower maternal kin available for allomaternal assistance. This suggesting that mothers would need to rely more on paternal kin and unrelated individuals as potential allomothers, or for at least some of the mother's kin to temporarily reside with the parents during periods of high need. However, we know that humans are ambilocal or bilocal, meaning either males or females may disperse, which can impact the availability of maternal or paternal kin. Bilocality may have led to the diverse use of both kin and non-kin as allomothers in humans. Allomothering appears to also be tied to the environment, with increased levels of allomothering seen in regions of reduced climate predictability and lower average temperatures and precipitation.
Cognitive & hormonal implications
Human females respond to social conditions during and immediately after pregnancy and may decide to abandon, neglect or commit infanticide if social support is lacking, if the infant is not considered viable (low birth weight, twins) or under certain extreme conditions (such as famine). Nearly all individuals show a response to infant crying and laughing, including fathers, virgin females, older children and even strangers. Oxytocin and prolactin, hormones released by mothers during lactation that may facilitate bonding, are also produced by males and others in the presence of a crying infant.
Infants appear to have coevolved adaptations in response to those in older children and adults. Infants that look healthier (larger or plump) have higher rates of survival. Newborn humans are also predisposed to seek out faces and will imitate faces they see or respond to attention by smiling and laughing. Smiling and laughing appears to be an attempt to draw in potential allomothers, as well as a way to bond with parents. Likewise, older infants can learn the intentions of others. Humans show advanced theory of mind and the ability to read and predict others' behavior and point of view may be impart due to the high levels of allomothering seen in humans. Early infants engage other humans through laughter, they quickly learn to discriminate between those that show them more attention and care for them, indicating that they possess a quickly understanding who intends to care for them. Also, there is evidence for cognitive and socialization implications in nonhuman primates' allomothering.
Emotional health implications
Allomothering can be helpful in the emotional health of both mother and infants
Mothers:
About the mothers, it is shown that the mothers' social network and supports that are provided through the cooperative breeding system or “availability of others” may mitigate not only the burden of physical pregnancy but also the psychological and emotional burden of motherhood. This reduced pressure on mothers contributes to the improvement of their well-being and parental investment. It is shown that a lack of support from social networks would lead mothers to abandon their children and increase the risk of postpartum depression. In this vein, Hagen (1999) suggested that post-partum depression might help mothers to show their need for social support. For example, research showed that the emotional support of infants' maternal grandmothers was associated with less depression in the mothers. In this study, the interesting finding was that the positive influence of maternal grandmothers' support in decreasing mothers' depression risk was not related to the geographic proximity of the grandmothers.
Infants:
Mothers' post-partum depression can cause reduced parental investment and not responding to infants' cues for their needs. As a result, the ignorance of infants' cues can affect their secure attachment and cognitive functions. Hence, the caregiving network can decrease these negative consequences.
Cameron (1998) mentioned that in mammals generally, some mammals' offspring may suckle the breast for soothing in distressed situations rather than/ as well as for nutritive purposes. Then, Hewlett and Winn suggested that the need for soothing in the distressed situation may be a reason for the evolution of allo-maternal breast suckling (allo-nursing/ allo-suckling) although this is less accepted than the other potential proposed explanations of allomothering.
Immunity implications
The allo-nursing specifically discusses the idea of breastfeeding other individuals' offspring of both kin and non-kin. Since all-nursing is costly for females, there have been many hypotheses to explain the possible reasons for its evolution. One of the hypotheses is the “neuroendocrine function of allosuckling “(NFA).
Based on NFA, both infants, and allo-mothers can benefit from the function of allo-nursing. For example, as a benefit for the allo-nursers, an infant, through suckling, can stimulate the nipple to produce prolactin. Prolactin production can cause fertility suppression and immune system improvement in allonursers. In addition, prohibiting fertility can be beneficial for females and their own offspring especially when their own infants do not stimulate their mothers' nipples.
This hypothesis also predicts that allo-nursing with the increased prolactin and its positive consequences in the immune system in allonursers, are more common in mammals living in an environmental setting with a higher load of parasites.
Infants also can be provided by different bacteria through being breastfed by allo-mother/s. The bacteria can be transmitted by skin-to-skin contact and by milk through the process of allo-nursing. Indeed, there is a critical period in infants' development in which the gastrointestinal is colonized by bacteria to shape the gastrointestinal microbiome (GIM). Regarding hygiene and the related hypothesis including the old friends' hypothesis, it is shown that this period of colonization is critical because colonization helps the development and education of the immune system.
Human milk microbiome (HMM) is found to be important for the colonization of GIM and consequently for the development of the immune system in infants because during the critical period, HMM is the first and most reliable source of bacteria, and this modulates the immune system of infants.
Studies on small-scale societies including foragers (hunter-gatherer) and horticulturalists, showed that allo-nursing is more common among forager women who live in tropical environments (with higher loads of parasites and bacterial infections) than the more arid environment in which infectious diseases are lower.
In the tropical environment, most of the death in small-scale societies is because of parasite, bacterial, viral infectious diseases. Some of these tropical forager societies in which allo-mothering nursing is common are the Ache, Bofi, Agta, Aka, Efe´, Chabu, and Onge´e but it is not common in the forager societies like the Nayaka, Hadza, Paliyan, Martu and !Kung who live in the non-tropical area.
However, the studies showed some exception in horticulturalist in tropical area like Ngandu in which the allo-nursing is discouraged and researchers believe that it may be due to the knowledge about increasing possibility of common infection transmission through breastfeeding in their populated villages. Yet, for the Aka people the primary reason of death is parasite not transmission of other infections. Therefore, allo-nursing, due to NFS and its immunological positive consequences, can benefit Aka women and benefits of allo-nursing may be higher than the cost of infection transmissions.
Furthermore, the size and frequency of caregiving network existing in allo-mothering practices can affect the diversity and bacterial composition of human milk and this may influence infants' immune system and health. The research that has addressed the relationship between HMM and infants' immunity, emphasis the need for more studies since the interaction between the microbes and immunology is complicated.
Allomothering by kin
Hrdy states that the altruism of allomothers can be explained by Hamilton's rule and therefore allomothers enhance their inclusive fitness by helping kin. However, in humans, bilocality and complex cultural norms around marriage or mating produce groups that may not be highly related suggesting that allomothering is not limited to kin. Despite varying and complex residential patterns, kin do appear to be strong sources of allomaternal care in many societies. Fathers, grandparents, older siblings and other close kin help in childcare, provisioning, protection and education.
Allomothers are perhaps less important immediately after birth. Infants rely on the mother for milk to survive and mothers benefit from food provisioning by the fathers to produce sufficient amounts of milk for their infants. Infants whose mother's die during childbirth have a low probability of survival, between 1-5% in some pre-demographic transition populations, higher in post-demographic transition populations. If the mother dies during the first year of life the chance of survival increase to 35-50%, and the effect of the mother's death nearly disappears after the child reaches two. This indicates the important of parents during the first couple of years of life, but also demonstrates that once weaning is complete, allomothers are capable of rearing children to adulthood.
Fathers
The importance of fathers varies considerably, but many authors now agree that there is little impact on child survival from the loss of a father. Sear and Mace's study of 15 populations found that in 53%, the death of the father was not correlated with an increase in child mortality. The father does not directly feed an infant and it is possible that other males of the family or community can step in if something happens to the father. Kramer's (2010) cross-cultural study found that in direct allomaternal care provided by fathers varies from less than 1% (Alyawara) to nearly 16% (Aka) with an average of 4.8% across the populations studied. However, in many societies the father does play an important role. Among the Ache of South America, the loss of the father did affect the child's survival. Meat sharing by hunters is an important part of Ache life and, while the majority of the meat acquired by a male may not go directly to the family, it is used to build relations and exchange for other goods. Interestingly, the father is not very involved in childcare among the Ache. The same study found that among the Hiwi (also of South America), where the father does provide direct childcare and food provisioning, the death of the father had no effect on child survival.
A father's most important contribution to children may be providing protection from other males, especially in groups that practice infanticide. Sear and Mace point out that many of the populations in the study look at the impact of the loss of a father on young children and suggest that since a father cannot provide direct nourishment to breastfeeding children, their importance may come later in the child's life. Fathers teach subsistence strategies to older children (for example, teaching hunting and trapping skills to older boys in hunter-gatherer societies). Allal et al. found that the marriage and fertility of women who do not have fathers may be impacted. Some hunter-gather populations in South America also have “partible paternity”, the idea that multiple men can impregnate a woman and all are considered the father, which could provide “back-up” fathers to children.
Grandparents
Grandmothers can care for children freeing the mother to engage in foraging or economic activities, or in the care of a child that has not been weaned. Likewise, grandmothers often continue to forage late in life to help with food provisioning for their grandchildren and a lactating mother. Child mortality in rural Gambia saw a significant decline when the maternal grandmother was present (see Table 4). In a comparison of nine populations on the proportion of direct childcare received by a child, Kramer found that grandmothers accounted for between 1.2% (Maya) and 14.3% (Mardu) of the total childcare. Sear and Mace determine that grandmothers do not have a universally positive effect on child survival and there is a difference between maternal and paternal grandmothers. Maternal grandmothers improved child survival in 69% of cases while paternal grandmothers improved survival in only 53% of observed cases. They also found that paternal grandmothers were detrimental in two cases and maternal grandmothers in one. Paternal grandmothers may on average be older than maternal grandmothers, due to common age differences in males and females at first reproduction. Paternal grandmothers may also be more reluctant to invest in their grandchildren due to the lack of certainty of paternity. The same study also found the timing of impact of paternal and maternal grandmothers varies, with maternal grandmothers having greater effects after the first year of life (allomaternal care) and paternal grandmothers having greater effects during pregnancy and in the first few months of a child's life (help with tasks during pregnancy or causing high levels of stress to the mother during pregnancy).
Grandfathers do not appear to be important sources of allomaternal care, with maternal grandfathers having no impact on child survival in 83% of cases and paternal grandfathers having no impact on 50% and a negative impact on 25% of cases. Little explanation on why grandfathers contributed less to childcare was found in the anthropological literature. It is possible that the even greater age of a grandfather when compared to grandmothers made it difficult to help with childrearing. In addition, grandfathers, like fathers, may contribute primarily through food provisioning, however the late age of the grandfather is likely to be well passed his hunting prime.
Grandmother hypothesis
Grandmothers are often considered a significant source of allomaternal care and this fact has led to the “grandmother hypothesis”, suggesting that women developed long post-menopausal periods to help with their children's offspring. This long lifespan after menopause is unique to humans and may help explain early weaning and high fertility rates. Hill and Hurtado argue that early reproductive senescence in females is an evolutionary dilemma since natural selection should favor continued reproduction. They test the grandmother hypothesis with data collected from the Ache and determine it does not support the idea that early menopause is maintained by natural selection favoring women who stop reproduction in order to invest more in their grandchildren. Despite Hill and Hurtado's finding, grandmothers often account for a much of the allomaternal care seen in a variety of societies.
Siblings
Older siblings may be the greatest source of allomaternal care among kin. Kramer's (see Table 1) comparison of nine populations found that siblings accounted for between 1.1% and 33% of the direct childcare received by a child. Older sisters appear to be more important than brothers for many of the groups in the study with sisters ranging from 5% - 33% and brothers 1.1% - 16.3%. Ivey (see Figures 1 & 2) found that among the Efe, both sisters and brothers contributed significantly to childcare. Sear and Mace found that five of the six studies indicated that child mortality increased survival of younger siblings. Older siblings, while still dependent on their parents. can engage in a variety of useful tasks depending on their age. It is possible that dependence on adult allomothers was not an early selective pressure for the development of allomothering in humans, but rather maternal – juvenile cooperation likely played a more important role.
Older sisters often engage in childcare, helping to look after younger siblings. This is apparently true regardless of subsistence strategy; and holds true even for Industrial societies. Kramer (see Figure 4) shows a cross cultural comparison of children in ten societies, all of whom engage in at least some childcare of younger siblings. Equally important, older children can help offset their own cost by engaging in foraging or economic actives. The same figure from Kramer shows that all of the groups engaged in more economic work than childcare. Kramer (see Figure 2) compares groups organized by subsistence strategy and shows that foraging and economic work are common among foragers, horticulturalists, agriculturalists and pastoralists, with the latter two groups showing some of the highest rates of food production and domestic tasks by children.
Extended family
Other kin may be sources of allomothers when present, however evidence from the ethnographic literature demonstrates varied amounts of contribution and different impacts on the children. Aunts' and uncles' contribution varies depending on residential patterns, inheritance patterns and resource allocation. Among the Kipsigis of Kenya, a child's paternal uncle had a positive effect on reducing child mortality in the richer half of the sample but not on the poorer half, however for maternal uncles the effects were reversed with poorer families showing a greater reduction in child mortality. Local resource competition, namely conflict over land inheritance among the father's brothers appears to account for the pattern of paternal kin effects. Others have found that the maternal aunts have similar effects in societies with female inheritance. Efe infants spend a significant amount of time in the care of aunts and male cousins.
Allomothering by non-kin
Studies of extant hunter-gatherer groups demonstrates that groups are composed of more than just direct kin, with between 25 – 50% of group members as unrelated or distantly related. Using modern hunter-gatherers as representatives of past hunter-gathers is not a perfect analogy, the data in combination with archaeological and paleoanthropological evidence are the only sources of information we can use to reconstruct past groups. It is likely that past hunter-gatherer groups were also composed of a mixture of related (kin) and unrelated (non kin) individuals meaning that allomothering by non kin occurred in at least some past societies. Research with contemporary hunter-gatherers, horticulturalists, and modern, industrial societies often finds that non-kin – friends, neighbors, and fictive kin – provide allomaternal care.
Surrogate breast feeders, known as a wet nurses in Western medical literature, may have played an important role as allomothers prior to the introduction of bottle feeding and formula. Wet nursing was recorded in ancient Israel and Egypt, among historical and modern Sunni Arab populations, as well as in ancient India and Greece. While the frequency of wet nurses has been debated, there is ample references in the literature to suggest that is did occur (and in some societies still does).
Religion and religious communities may also increase the frequency of allomothering. Studies of religious communities in England and New Zealand show increased allomaternal care by unrelated members of the community. Religion is thought to increase prosocial behavior with religiosity being a costly signal that indicates to other members that a practicing individual is trustworthy and likely to cooperate and reciprocate. Israeli kibbutz are collective settlements where members share almost all aspects of their lives: all incomes are given to the kibbutz an in return the kibbutz distributes goods and services equally, they dine in communal dining halls and childcare is communal. Children live in a communal nursery and later group houses together. Parenting is also distributed among the community; perhaps an extreme form of allomothering.
Fictive kin are unrelated individuals that have kinship terms bestowed on them. There are generally two types of fictive kin: named kin, determined by factors such as age, gender and prestige and applied to a large number of community members (such as in Northern India), and ritual kin, named at a specific ceremony, such as baptism, at which time the relationship between the individual undergoing the ceremony and the named kin is formalized. Named kin may function similarly to religious communities by increasing familiarity and increasing prosocial behavior, however little research appears to have been conducted on this form of fictive kin. Godparents are one of the better-known ritual kin systems in Western culture. Godparents are common to Catholic (and other Christian) communities in Europe and throughout the Americas (due to colonization). Godparents are expected to provide extra resources to the family; naming a godparent creates a strong bond within the community or a tie to an outside community where new resources may be accessible in times of need. Other examples of ritual kin are milk kin in some Arab societies and the Japanese oyabun-kobun system.
In a literature review of alloparental care, Kenkel et al. found that children are between six and hundred times more likely to die from abuse while under the care of unrelated adults in modern societies, however they also state that the term alloparenting is often omitted from studies on modern populations resulting in "blind spots" in the literature.
In urban/industrial societies
The nuclear family has dominated U.S. and some European populations life for many decades. The typical family is often thought of as two parents and their children living in one house. However, a recent poll by the Pew Research Center shows a rise in the number of U.S. Americans living in multigenerational homes, from a low of 12% in 1980 to 20% in 2016. The growing price of housing in the U.S. and the overall rise in the cost of living has made owning homes and living as a nuclear family more difficult. It is once again becoming common for grandparents to live in the same house as their grandchildren, providing a source of childcare for the families. Urban areas in China also show that while two generation and single parent households are on the rise, however the extended family still represents the majority of Chinese households. Older siblings in most modern, industrialized are required to attend school, possibly eliminating a source of allomothering, it appears that grandmothers still play an important role in childcare.
Wet nursing may still be an option in some societies. The Arab populations previously mentioned still have wet nurses but the occurrence is quickly declining, however modern technologies like formula and breast pumps have made it unnecessary in populations with access to those technology. Ritual kin systems, such as godparents and the oyabun-kobun system, are also still active in their respective societies and may still function as a source of allomaternal care. Religious communities within modern societies are still relevant as Shaver et al. has shown in their studies in England and New Zealand.
In industrialized, urban societies daycare, school, nannies, etc. may provide many of the same benefits that would have traditionally been provided by kin and well-known community members. It is possible for parents in urban areas to enroll in daycare as soon as weaning is complete (sometimes early with breast-pumping technology) and as long as resources or finances permit, the child could be looked after for the duration of the day. The cost of these services may be prohibitive to many low-income families, creating a divide in allomaternal care depending on income. It is also unclear whether the primary role of a service such as daycare is to allow for more attention to producing more children or allowing parents to pursue other endeavors (careers). The research into daycare as a form of allomothering may be complicated by its cost and other limitations to access. Daycare may be more common among wealthy and/or higher educated individuals who are less likely to have children out of choice, meaning discerning impact on interbirth intervals or other metrics may be challenging.
Allomothering is still relevant in most industrialized societies, even if the source has shifted. Reliance on extended family may have fallen, but recently is on the rise, and more use of paid childcare system such as daycare or compulsory systems such as schooling fill in some of the gaps that occur from living in a mobile, globalized, industrial society.
Critiques
There are a couple of critiques to consider related to cooperative breeding and allomothering in humans. The first is proposed by Bogin et al. in which they argue that humans are not actually cooperative breeders. The authors argue that because allomothering and provisioning are not based on genetic relatedness, as most other cooperative breeders are, the term needs to be modified to incorporate the wider range of behavior seen in humans. They propose the term “biocultural reproduction” that they believe better describes the high amount of allomothering by kin and non kin, and accounts for the variation in allomothering practices seen from culture to culture in humans. This critique does not apply specifically to allomothering as discussed in this article, but rather to the reproductive strategy system that incorporates it.
The second critique relevant to allomothering concerns human kinship distinctions. Schneider, along with other anthropologists, have argued that distinguishing between real and fictive kin does not always occur in human cultures and perhaps should be abandoned. The critique may be misunderstood to mean that humans cannot tell the difference between related and unrelated individuals. Maternity in humans, like many other animals, is known and the mother's female relatives relatedness can be assumed by individuals with relative certainty. Humans are also unique as fairly stable pair-bonding allows for some degree of paternal certainty. In fact, Chapais argues that patrilineal kinship is a prerequisite for the flexibility of residential patterns seen in humans and this kinship is not culturally based but has a deep biological substrate upon which it is built. Gintis and Chapais arguments suggest that while kinship terms are often applied to individuals outside of related individuals, the relatedness of those individuals is known. A distinction is still useful and we see a difference in the contribution of allomothering by related versus unrelated individuals in many, if not most populations.
References
Parenting
Sociobiology | Allomothering in humans | [
"Biology"
] | 6,777 | [
"Behavioural sciences",
"Behavior",
"Sociobiology"
] |
67,578,967 | https://en.wikipedia.org/wiki/Classical%20shadow | In quantum computing, classical shadow is a protocol for predicting functions of a quantum state using only a logarithmic number of measurements. Given an unknown state , a tomographically complete set of gates (e.g. Clifford gates), a set of observables and a quantum channel defined by randomly sampling from , applying it to and measuring the resulting state, predict the expectation values . A list of classical shadows is created using , and by running a Shadow generation algorithm. When predicting the properties of , a Median-of-means estimation algorithm is used to deal with the outliers in . Classical shadow is useful for direct fidelity estimation, entanglement verification, estimating correlation functions, and predicting entanglement entropy.
Recently, researchers have built on classical shadow to devise provably efficient classical machine learning algorithms for a wide range of quantum many-body problems. For example, machine learning models could learn to solve ground states of quantum many-body systems and classify quantum phases of matter.
Inputs copies of an unknown -qubit state
A list of unitaries that is tomographically complete
A classical description of a quantum channel
For ranging from to :
Choose a random unitary from
Apply to to get a state
Perform a computational basis measurement on for an outcome
Classically compute and add it to a list
Return
Inputs A list of observables
A classical shadow
A positive integer that specifies how many linear estimates of to calculate.
Return A list where
where and where .
References
Quantum information science
Quantum information theory
Quantum measurement
Quantum computing | Classical shadow | [
"Physics"
] | 310 | [
"Quantum measurement",
"Quantum mechanics"
] |
67,579,646 | https://en.wikipedia.org/wiki/Time%20in%20Slovenia | In Slovenia, the standard time is Central European Time (; CET; UTC+01:00). Daylight saving time is observed from the last Sunday in March (02:00 CET) to the last Sunday in October (03:00 CEST). This is shared with several other EU member states.
History
The Austro-Hungarian Empire adopted CET on 1 October 1891. Slovenia would continue to observe CET after independence, and observed daylight saving time between 1941 and 1946, and again since 1983.
Notation
Slovenia uses both the 12-hour and 24-hour clock.
IANA time zone database
In the IANA time zone database, Slovenia is given one zone in the file zone.tab – Europe/Ljubljana. Data for Slovenia directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
See also
Time in Europe
List of time zones by country
List of time zones by UTC offset
References
External links
Time in Slovenia at TimeAndDate.com.
Geography of Slovenia | Time in Slovenia | [
"Physics"
] | 211 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
67,579,823 | https://en.wikipedia.org/wiki/Cut%20glass | Cut glass or cut-glass is a technique and a style of decorating glass. For some time the style has often been produced by other techniques such as the use of moulding, but the original technique of cutting glass on an abrasive wheel is still used in luxury products. On glassware vessels, the style typically consists of furrowed faces at angles to each other in complicated patterns, while for lighting fixtures, the style consists of flat or curved facets on small hanging pieces, often all over. Historically, cut glass was shaped using "coldwork" techniques of grinding or drilling, applied as a secondary stage to a piece of glass made by conventional processes such as glassblowing.
Today, the glass is often mostly or entirely shaped in the initial process by using a mould (pressed glass), or imitated in clear plastic. Traditional hand-cutting continues, but gives a much more expensive product. Lead glass has long been misleadingly called "crystal" by the industry, evoking the glamour and expense of rock crystal, or carved transparent quartz, and most manufacturers now describe their product as cut crystal glass.
There are two main types of object made using cut glass: firstly drinking glasses and their accompanying decanters and jugs, and secondly chandeliers and other light fittings. Both began to be made using the cut glass style in England around 1730, following the development there of a reliable process for making very clear lead glass with a high refractive index. Cut glass requires relatively thick glass, as the cutting removes much of the depth, and earlier clear glass would mostly have appeared rather cloudy if made thick enough to cut. For both types of object, some pieces are still made in traditional styles, broadly similar to those of the 18th century, but other glassmakers have applied modern design styles.
Expensive drinking glasses had previously mostly concentrated on elegant shapes of extreme thinness. If there was decoration it was mostly either internal, with hollow bubble or coloured spirals within the stem ("twists"), or surface decoration in enamelled glass or glass engraving. Outside Venice and Spain, lighting fittings had not previously made much use of glass in Europe; the enamelled mosque lamp of Islamic art was a different matter. But cut glass "drops", faceted in a style derived from gem cutting in jewellery, refracted and spread the light in way that was new, and were enthusiastically embraced by makers and their customers. The main skeleton of the chandelier was very often metal, but this was often all but hidden by a profusion of faceted glass pieces, held in place by metal wire.
Technique
In the first century AD, Pliny the Elder described how patterns may be cut on glass vessels by pressing them against a rotating wheel of hard stone. The process of cutting has stayed the same in modern times apart from changes in details since that description in the middle of the first century AD. It has always used a small rotating wheel of, or coated with, some abrasive substance, and usually with a liquid lubricant such as water, perhaps mixed with sand, falling onto the area being worked and then being collected below. The wheels were originally powered by treadles, but by the mid-19th century workshops had several stations linked to steam power. Today electric power is used. For cutting flat facets a turntable device called a "lap", already used in gem-cutting, was adopted.
Typically the design is marked with paint on the glass before cutting – in England red is usually used. One advantage of cut glass for the manufacturer is that it can very often be arranged for the small flaws such as bubbles that are inevitable in a proportion of glass pieces, and would lead to a clear piece being rejected, to be placed in the areas to be cut away. Conversely, if imitation cut glass using moulds is made, the complexity of the mould shapes greatly increases the number of faults and rejects.
A second operation polishes the cut glass, traditionally using a wooden or cork wheel "fed with putty powder and water". In the late 19th century, an alternative method using fluoric acid was introduced; this made the process of polishing faster and cheaper. However, it "gives a dull finish and tends to round off the edges of the cuts".
Labour was the main cost in making cut glass. Arguing against the reduction of tariffs in 1888, a leading figure in the American industry claimed that "We take a piece of glass .... costing 20 cents and .... in many cases put $36 of labor on it".
History
Technically, the decorative "cutting" of glass is very ancient, although the term "cut glass" generally refers to pieces from the 18th century onwards. The Bronze Age Indus Valley civilization made glass beads that were engraved with simple shapes. Ancient Roman glass used a variety of techniques, but mostly large amounts of drilling, often followed by polishing, to produce the deeply under-cut cage cups, objects of extreme luxury, cameo glass in two colours, and objects cut in relief, of which the Lycurgus Cup is the outstanding survivor.
Islamic art, especially that of the Fatimid court in Egypt, valued bowls and other objects in "carved", that is, cut rock crystal (quartz, a clear mineral), and this style was also produced in glass, which was cheaper and easier to work. Cameo glass was also produced. Similar relief effects were also achieved even more cheaply in mould-blown glass. The 13 or 14 surviving examples of the so-called Hedwig glasses were probably made by Islamic artists, but perhaps for the European market. Perhaps from the 12th century, they are either very late examples of Islamic glass-cutting, or isolated ones of medieval European use of the technique.
Very shallowly scratched or cut engraved glass was revived by at least the Renaissance, but there was very little use of deeper cutting which, however, continued to be used in rock crystal and other forms of hardstone cutting. In Germany in the late 17th and early 18th centuries there was a revival, for "two generations", of cut relief decoration, water-powered and imitating rock crystal. Typical pieces were cups and goblets with coats of arms surrounded by rich Baroque ornament, with the background cut away to leave the reliefs raised. This is called the Hochschnitt ("high cut") style.
In the later 17th century George Ravenscroft developed a cheap and reliable lead "crystal" glass with a high refractive index in England, which various other glassmakers adopted. After some time, the potential of cut glass using this basic material began to be realized; a high lead content also made the glass easier to cut.
Chandeliers
In the early 18th century, bevelled edges to large mirrors became fashionable in England, achieved by rubbing with abrasives, but also by "cutting". The making of "looking glasses" was a different branch of glassmaking from the makers of drinking glasses, and it seems to have been in the former that "the craft of cutting was born", and the mirror makers were the workshops who expanded into chandeliers.
A London glassmaker advertised in 1727 that he sold "Looking Glasses, Coach Glasses and Glass Schandeliers". The earliest examples, like that given to the chapel in Emmanuel College, Cambridge, in 1732, were glass versions of the standard brass designs long used in England, imported or locally-made versions of a Netherlandish and north French design style that had been developed since the 15th century. Around the mid-century, designs took up the use of multiple faceted pendants, which had been used in the enormously expensive chandeliers of the French court, where instead of glass carved clear rock crystal (quartz) had been used.
Over the rest of the 18th century, and the early part of the next the number of drops increased, and the main stem of the chandelier, typically in metal, tended to disappear behind long chains of them. By the Regency period there might be "some thirty drops in perhaps six or eight graded sizes, and each drop might have 32 facets on each side. Costs soared." The dominance of cut glass in other lighting devices such as candlesticks, sconces, girandoles, and lamps was never as complete, but all were often made in it.
By 1800 it was already common to dismantle chandeliers and reconfigure them into a more fashionable shape, and subsequently most old chandeliers have been converted from candles to electricity, often after a period as gasoliers using lamp oil.
Vessels
Starting out by decorating mainly wine glasses, decanters and other drinkware, by the 19th century cut glass was used for a variety of tableware shapes, mostly those associated with desserts ("sweetmeat glass" is a term used by collectors), and for bowls and trays either for use at the table or in the drawing room. These larger shapes allowed the room for cutters to produce many of the most interesting and characteristic cut designs, which experts can often date rather precisely, as they passed through several different styles. Starting with the Rococo, there were Neoclassical and Regency styles, and finally one with "Gothic" arches by about 1840. The Regency style added to the 18th-century diamond shapes zones with many parallel bands, furrows, or flutes, either vertical or horizontal, initially rather narrow, but later wider, in the "broad flute" style. From about 1800 to 1840 "almost all British luxury table glass was cut", and the style spread to Europe and North America. English cutters were instructing French workers at the Saint-Louis glass factory by 1781, and later Belgian cutters at Val Saint Lambert by 1826.
On wine glasses and similar shapes, the rim where the drinker's mouth would touch was left smooth, but the bowl, especially the lower part, the stem, and the foot might be cut. A starburst on the underside of the foot was common. On jugs, cups for eating desserts from, and bowls the rim was often cut with zig-zags or other ornament. Especially in the 18th century, cutting was often combined with glass engraving above, and by the 1840s it was popular to have areas of "frosting", rubbing the glass with abrasives to reduce its transparency.
Competition from cheaper, but lower quality pressed glass in the cut glass style began as early as the 1820s, and grew greatly in the 1830s, but the British cut glass industry continued to expand. In 1845 a commentator stated "cut-glass is now comparatively cheap". The ability of British glass designers to patent their designs after 1842 was a help; the mould makers (often called "die-sinkers" in the trade) were apparently often independent of the glass factories. At least in America, where the cut glass industry was growing rapidly, "cutting shops" were also often, or usually in the 19th century, independent operations buying glass blanks from the glassmakers. In the 1870s Bohemian cutters began to arrive in Corning, New York, one of the centres of the industry, supplementing English immigrants.
1850 onwards
The centrepiece at the crossing of the Crystal Palace holding the Great Exhibition of 1851 in London was a huge glass fountain (8.25 metres or 27 feet high), including much cut glass, by the leading Birmingham firm of F. & C. Ostler. Cut glass had dominated both its main market niches for several decades, but a number of factors were about to challenge it, at least as far as vessels were concerned. The Victorian taste for over-ornamentation was beginning to take over, and some of the cut glass displayed at the Great Exhibition was described as "prickly monstrosities". In the year of the exhibition, the hugely influential critic John Ruskin, in his Modern Painters, denounced the whole technique, writing "We ought to be ashamed of it" and "all cut glass is barbarous, for the cutting conceals its ductility and confuses it with [rock] crystal".
At the same time, and further stimulated by the Great Exhibition itself, the British style was spreading across the Western world, and in particular cut American and Bohemian glass was attacking the British market. The previous excise duty long charged on glass was abolished in 1845, which both encouraged the development of exciting new styles of decorating glass, and also made glass cheaper, leading to a flood of pressed glass imitations of cut glass style that tended to devalue the prestige of the style. Nonetheless, cut glass remained a staple in most prosperous British households, and was still widely exported.
In the 1870s the "brilliant", "brilliant cut" or "American Brilliant" style emerged, perhaps first seen in America in glass exhibited at the 1876 Philadelphia Centenary Exhibition: "its most complex brilliant cutting involved covering the glass surface with intersecting cuts that created innumerable, often fragmentary shapes making up larger patterns. Basic motifs used were stars, hobnail or polygonal diamonds, strawberry diamonds and fan scallops...".
Decline
The last decades of the 19th century saw exciting new developments in glass design, with much use of colour, the Victorian version of cameo glass using glass etching, opaline glass in France, and other innovations. Cut glass, especially in the brilliant style, did not mix well with these – the great majority of it has always used clear glass. An exception is the distinct Japanese style of Satsuma kiriko, which adds a thin layer of coloured flashed glass which is then cut through, giving a colour contrast. Similar effects were sometimes used in the West, especially in continental Europe. Cut glass vessels remained popular, but an increasingly conventional and conservative taste, little used for art glass, a new term for decorative glass with artistic aspirations. This was even more the case with Art Nouveau glass and that of the Arts and Crafts Movement, which both took on board Ruskin's criticisms, and preferred sinuous curving forms that emphasized the flowing, frozen liquid nature of glass.
At the end of the century the market for expensive decorative glass appears to have slumped, perhaps because so much was now being made and traded internationally. Corning's cut glass industry peaked in 1905, when a directory recorded 490 cutters there, and 33 engravers, though the quality of some work was falling; by 1909 the number of cutters had fallen to 340.
The arrival of Modernism in the early 20th century did not do much to change this, and in 1923 an English expert complained that "to the aesthetic soul [cut glass] is still a thing accursed ... a striking testimony to the persistence of Ruskin's influence". He tried to do a survey of likely owners of 18th-century cut glass such as historic houses, Oxbridge colleges and London livery companies, but found very few would admit to owning any.
But some glassmakers, for example in Art Deco, were sympathetic to linear and geometric decoration and made use of the technique, often as one of a number of techniques used in a single piece. This continues to be the case in the recent studio glass movement. In mid-20th-century England there was a revival in engraved glass, which was often accompanied by some cutting; the work of Keith Murray includes examples. Traditional cut glass designs are still used, for example in what Americans call the Old fashioned glass, a whisky or cocktail tumbler. In chandeliers, however, the clear cut glass style has been adapted successfully to modern styles and still holds its own, especially for large public spaces such as hotel lobbies.
Cut-glass accent
In British English, a "cut-glass accent" is an especially clipped version of British upper-class Received Pronunciation, where "words are pronounced very clearly and carefully". The accent is agreed to be less common now than it was several decades ago, with even leading exponents such as Queen Elizabeth II having softened their pronunciation over the years.
Notes
References
Battie, David and Cottle, Simon, eds., Sotheby's Concise Encyclopedia of Glass, 1991, Conran Octopus,
Davison, Sandra and Newton, R.G., Conservation and Restoration of Glass, 2008, Taylor & Francis, google books
Farr, Michael, Design in British Industry: A Mid-century Survey, 1955, Cambridge University Press, google books
"History": "A History of the Chandelier"
Osborne, Harold (ed), The Oxford Companion to the Decorative Arts, 1975, OUP,
Powell, Harry J., Glass-making in England, 1923, Cambridge University Press, google books
Sinclaire, Estelle F., Complete Cut and Engraved Glass of Corning (New York State Series), 1997, Syracuse University Press, google books
Sparke, Penny, "At the Margins of Modernism: The Cut – Crystal Object in the Twentieth Century", 1995, Bulletin of the John Rylands University Library of Manchester, 1995 , 77 ( 1 ) : 31–38, PDF
Further reading
Fisher, Graham, Jewels on the Cut: An Exploration of the Stourbridge Canal and the Local Glass Industry, 2010, Sparrow Books
Spillman, Jane Shadel, The American Cut Glass Industry: T.G.Hawkes and His Competitors, 1999, ACC Art Books
Swan, Martha Louise, American Cut and Engraved Glass of the Brilliant Period in Historical Perspective, 1986, Gazelle Book Services
Warren, Phelps, Irish Glass: Waterford, Cork, Belfast in the Age of Exuberance (Faber monographs on glass), 1981, Faber & Faber
Glass
Drinkware
Chandeliers
History of glass | Cut glass | [
"Physics",
"Chemistry"
] | 3,606 | [
"Homogeneous chemical mixtures",
"Amorphous solids",
"Unsolved problems in physics",
"Glass"
] |
67,580,288 | https://en.wikipedia.org/wiki/Time%20in%20North%20Macedonia | In North Macedonia, the standard time is Central European Time (; CET; UTC+01:00). Daylight saving time is observed from the last Sunday in March (02:00 CET) to the last Sunday in October (03:00 CEST). This is shared with several other EU member states.
History
North Macedonia observed daylight saving time between 1941 and 1945, and again since 1983 (by this time part of Yugoslavia).
IANA time zone database
In the IANA time zone database, North Macedonia is given one zone in the file zone.tab – Europe/Skopje. Data for North Macedonia directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
See also
Time in Europe
List of time zones by country
List of time zones by UTC offset
References
External links
Current time in North Macedonia at Time.is
Geography of North Macedonia | Time in North Macedonia | [
"Physics"
] | 186 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
67,580,479 | https://en.wikipedia.org/wiki/Time%20in%20San%20Marino | In San Marino, the standard time is Central European Time (CET; UTC+01:00). Daylight saving time is observed from the last Sunday in March (02:00 CET) to the last Sunday in October (03:00 CEST). This is shared with several other EU member states.
History
San Marino observed daylight saving time between 1916 and 1920, 1940, 1942 to 1948, and again since 1966.
IANA time zone database
In the IANA time zone database, San Marino is given one zone in the file zone.tab – Europe/San_Marino. Data for San Marino directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
See also
Time in Europe
List of time zones by country
List of time zones by UTC offset
References
External links
Current time in San Marino at Time.is
Geography of San Marino | Time in San Marino | [
"Physics"
] | 185 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
67,580,740 | https://en.wikipedia.org/wiki/Time%20in%20Monaco | In Monaco, the standard time is Central European Time (CET; UTC+01:00). Daylight saving time is observed from the last Sunday in March (02:00 CET) to the last Sunday in October (03:00 CEST). This is shared with several other EU member states.
History
Monaco followed "Paris Mean Time" from 28 March 1911 until after World War II, when Monaco adopted CET.
IANA time zone database
In the IANA time zone database, Monaco is given one zone in the file zone.tab – Europe/Monaco. Data for Monaco taken directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
See also
Time in Europe
List of time zones by country
List of time zones by UTC offset
References
External links
Current time in Monaco at Time.is
Geography of Monaco | Time in Monaco | [
"Physics"
] | 180 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
67,581,888 | https://en.wikipedia.org/wiki/Spangold | Spangold is a family of shape memory-effect alloys (SME) of gold, copper, and aluminum in either 18K or 23K. The name of the family is a play on the word "spangled".
Spangold is a beta-phase alloy with a nominal stoichiometry of Au7Cu5Al4 and a nominal composition by mass of 76% gold, 18% copper, and 6% aluminum. The texture is caused by the induction of a martensitic-type phase transformation on a polished surface.
Spangold undergoes a martensitic-type phase transformation when properly treated. This phase transformation is induced on a polished surface of the alloy. Martensitic transformations are a common feature in shape memory alloys, and they involve a reversible change in crystal structure that allows the material to recover its original shape when subjected to specific temperature changes.
References
Precious metal alloys
Aluminides | Spangold | [
"Chemistry"
] | 188 | [
"Precious metal alloys",
"Intermetallics",
"Alloys",
"Aluminides"
] |
67,581,910 | https://en.wikipedia.org/wiki/Pathogen%20avoidance | Pathogen avoidance (also parasite avoidance or pathogen disgust) refers to the theory that the disgust response, in humans, is an adaptive system that guides behavior to avoid infection caused by parasites such as viruses, bacteria, fungi, protozoa, helminth worms, arthropods and social parasites. Pathogen avoidance is a psychological mechanism associated with the behavioral immune system. Pathogen avoidance has been discussed as one of the three domains of disgust which also include sexual and moral disgust.
Evolutionary significance
In nature, controlling or the avoidance of pathogens is an essential fitness strategy because disease-causing agents are ever-present. Pathogens reproduce rapidly at the expense of their hosts' fitness, this creates a coevolutionary arms race between pathogen transmission and host avoidance. For a pathogen to move to a new host, it must exploit regions of the body that serve as points of contact between current and future hosts such as the mouth, the skin, the anus and the genitals. To avoid the cost of infection, organisms require counteradaptations to prevent pathogen transmission, by defending entry points such as the mouth and skin and avoiding other individual's exit points and the substances exiting these points such as feces and sneeze droplets. Pathogen avoidance provides the first line of defense by physically avoiding conspecifics, other species, objects or locations that could increase vulnerability to pathogens.
The pathogen avoidance theory of disgust predicts that behavior that reduces contact with pathogens, will have been under strong selection throughout the evolution of free-living organisms and should be prevalent throughout the Animalia kingdom. Compared to the alternative, facing the infectious threat, avoidance likely provides a reduction in exposure to pathogens and in energetic costs associated with activation of the physiological immune response. These behaviors are found throughout the animal literature, particularly amongst social animals.
Mechanism
In humans, the disgust responses are the primary mechanism for avoiding infection through behavior triggered by sensory cues. Tybur argues that pathogen disgust requires two psychological mechanisms: detection systems that recognize input cues associated with the presence of pathogens and integration systems that weigh cue-based pathogen threats with other fitness relevant factors and generate withdrawal or avoidance behaviors appropriately.
The genetic underpinnings of these neural mechanisms are to date, not well understood. There is some evidence to suggest that humans are capable of detecting visual and olfactory sickness cues before overt cues for the disgust response are produced.
Cues
Pathogens are typically too small to be directly observed and so require the presence of observable cues that tend to co-occur with them. These inputs take the form of recognizable cues.
Hygiene: The detection of displays of or physical evidence of unhygienic behavior.
Animals or Insect: Typically, animal or insect disease vectors such as mice or mosquitoes.
Sex: Behavior related to promiscuity of sexual activities
Atypical appearance: Infection cues in other individuals such as abnormal body shape, deformity, auditory cues such as coughing and contextual cues related to circumstances of increased risk of infection such as homelessness.
Lesions: Stimuli related to signs of infection on the surface of the body such as blisters, boils or pus.
Food: Food items with visible or olfactory signs of spoilage.
Computational structure model
Tybur proposed a model of how an information processing system might be structured. In this model, perceptual systems (vision, olfaction, etc.) monitor the environment for cues to pathogens. Then, a mechanism integrates cues from the different perceptual systems and estimates a pathogen index, an internal estimation of the probability that pathogens are present based on reliability and detection of cues. Finally context-dependent avoidance can only occur if additional information is taken as input- if other mechanisms exist that function to trade off pathogen presence against other fitness-impacting dimensions across various contexts. The expected value of contact is a downstream index that integrates other indices relevant to the costs and benefits of contact which then regulates the approach versus avoidance in an adaptive manner. This model is consistent with several empirical findings of how additional variables such as sexual value, nutrient status, kinship status, hormonal status and immune function also influence responses to pathogen cues.
Imperfections in pathogen detection
Signaling detection errors are prevalent in the pathogen avoidance system; there are two types of errors: a false alarm, where a pathogen avoidance response is deployed needlessly or a miss, where a pathogen avoidance was not deployed in the presence of infection risk, they depend on whether pathogens are present or not. The costs for not mounting an avoidance response in the presence of infection risk is assumed to be greater, suggesting that selection may be favoring a greater sensitivity to cue pathogens at the expense of specificity. This is thought to explain the law of contagion wherein, objects in contact with an infectious cue are themselves treated as infectious.
Pathogen counter-adaptations
Hosts and parasites are under reciprocal evolutionary selection for hosts to acquire adaptations to prevent pathogen transmission and pathogens to acquire traits to evade host defense, this is known as host-parasite coevolution.
Parasite manipulation of host behavior
Many parasitic species manipulate the behavior if their hosts in order to increase the probability of transmission and completion of a parasite's lifecycle, these are sometimes referred to as behavior-altering parasites. This is a widespread adaptive strategy that increases fitness benefits for the parasite. Parasites can affect host behavior in multiple ways by altering host activity, the host's microenvironment or both. A comparison across host and parasite taxa revealed that vertebrates that were infected were more likely to have impaired reaction to predators as a result of manipulation while infection in invertebrates lead to increase in the host coming in contact with predators.
Known factors of influence
Sex
Women consistently demonstrate higher disgust sensitivity than men. Evidence suggests that women respond more sensitively to disease threats than men. This is hypothesized to be consistent with the enhanced evolutionary role in women for protecting their offspring.
Sexual behavior
Sexual behavior with another individual, such as intercourse is a major source of pathogenic risk particularly for bacterial or viral infection. Research has found a negative relationship between sexual arousal and disgust, indicating that when sexual arousal increases disgust responses decrease. Additional evidence points to variation in pathogen avoidance traits and their relationship with sexual behavior. Individuals with high trait-level pathogen avoidance are less motivated to have sex with multiple partners. This suggests that individuals with a more active behavioral immune system might perceive the costs of sexual activity with multiple partners as higher than those with a less active behavioral immune system.
Terrestrial versus aquatic environments
Distinct properties of parasite transmission of aquatic and terrestrial ecosystems lead to differences in the avoidance behaviors in these environments, however, the mechanisms are quite similar. For example, marine parasites are estimated to spread at a rate two times faster than terrestrial counterparts due to a combination of the increased viscosity and density of seawater and the movement of water through tides and currents.
Political ideology
Researchers have suggested that elements of a conservative political orientation function to reduce individual exposure to infectious agents. These studies found that the relationship between pathogen avoidance and social conservatism was statistically robust. Multiple mechanisms have been proposed as pathogen-neutralizing aspects of conservatism such as in-group favoritism, cultural evolution favoring pathogen-neutralizing traditions and rituals, and advocating for tradition-adherence within a community. There is criticism of this association. Tybur argues that the relationship between social conservatism and pathogen avoidance is explained by sexual strategies associated with conservatism, such as orientation towards monogamous sexual strategies. Another study, suggests that a generalized response to social resources is a more plausible mechanism underlying in-group favoritism than adaptations to pathogen stress.
Non-human animal behaviors
As parasite avoidance is a selective pressure imposed on all living animals, there are commonalities in strategies, mechanisms and consequences of pathogen avoidance behavior across species.
Vertebrates
Mammals
Asian elephants (Elephas maximus) use branches to deter biting flies from areas of the body with thinner skin or that cannot be easily reached.
Rats use their saliva which possesses bactericidal properties, to protect themselves and potential mating partners from genital pathogens by licking their genitalia after copulation. Wood rats (Neotoma fuscipes) exhibit a unique behavior of placing bay leaves (Umbellularia californica) in or near their nest to prevent flea infestations. Canids will defecate and urinate away from the proximity of their dens to protect against oro-faecally transmitted parasites Newborns who cannot exit the den, will have fresh excreta consumed by their mothers, as parasitic ova take several days to hatch thus preventing infection.
Primates
Bonobos rely on visual, tactile and olfactory cues to determine contamination risk when presented with contaminated food items versus the uncontaminated control group. Mandrills engage in allo-grooming practices in which they avoid members of the same species with parasitic infection and rely on the smell of feces of conspecifics infected with parasites to discriminate those individuals. Evidence has shown that both chimpanzees and Japanese macaques (Macaca fuscata) engage in food washing to remove food soiled with bodily fluids and dirt as a contaminant avoidance behavior strategy.
Birds
Birds engage in body maintenance, nest maintenance, avoidance of parasitized prey, migration and toleration as ectoparasite avoidance behavior. These anti-parasite behaviors are central to bird hygiene. For example, birds preen to straighten and clean feathers but this also is used as a method to remove ectoparasites in their plumage.
Invertebrates
Crustaceans
Social lobsters engage in specialized den selection by preferentially choosing dens with uninfected lobsters over dens with lobsters infected with the PaV1 virus.
Insects
Bees have several steps to avoid parasitic invasion of a colony; avoidance parasite contact, recognition of parasites and subsequent rejection, and the avoidance of social parasite exploitation. Within the colony, parasitic avoidance include: having several queens, nest construction that prevents invasion, chemical cues, coordinated defense. In the event of parasitic invasion of a colony, bees resort to hygienic behavior defense as a last resort effort against parasite infection in which infected, dying and already dead bodies are removed from the nest.
Nematodes
The most comprehensive data on avoidance behaviors has been generated for C. elegans. They protect themselves from unfavorable effects of pathogenic bacteria by avoiding lawns on which Microbacterium nematophilum is found. Evidence suggests that C. elegans relies on its olfactory system for pathogen avoidance, by avoiding odors that mimic those infected by pathogenic bacterium. Genetic analysis has revealed three mechanisms involved in avoidance behavior: learning of pathogen avoidance based on G-protein signaling in chemosensory neurons, learning of pathogen avoidance behavior through serotonin signaling pathways, physical avoidance and reduced oral uptake of pathogens.
Medical implications
A study has suggested that the four pillars of human medicine: quarantine, medication, immunization and nursing or caring are extensions of behavioral defenses against pathogens seen in animals. Hart argues that more complex applications of pathogen avoidance behaviors seen in medicine can be attributed to advanced linguistic and cognitive capabilities and higher rates of sickness in humans compared to animals.
References
Immunology
Behavioral ecology | Pathogen avoidance | [
"Biology"
] | 2,307 | [
"Behavior",
"Behavioral ecology",
"Behavioural sciences",
"Immunology",
"Ethology"
] |
67,581,994 | https://en.wikipedia.org/wiki/Time%20in%20Iceland | Iceland observes UTC+00:00 year-round, known as Greenwich Mean Time or Western European Time. UTC+00:00 was adopted on 7 April 1968 – in order for Iceland to be in sync with Europe – replacing UTC−01:00, which had been the standard time zone since 16 November 1907. Iceland previously observed daylight saving time, moving the clock forward one hour, from 1917 to 1921, and 1939 to 1968. The start and end dates varied, as decided by the government. From 1941 to 1946, daylight saving time commenced on the first Sunday in March and ended in late October, and from 1947 to 1967 it commenced on the first Sunday in April, in all instances since 1941 occurring and ending at 02:00. Since 1994, there have been an increasing number of proposals made to the Althing to reintroduce daylight saving time for a variety of reasons, but all such proposals and resolutions have been rejected.
Most of Iceland lies within the geographical UTC−01:00 offset, including the capital Reykjavík, while the westernmost points of Iceland located west of 22.5° West, including Ísafjörður, lie within the geographical UTC−02:00 offset. Despite this, Iceland observes UTC+00:00 in order to be in sync with Europe, which results in noon being 88 minutes behind other countries in the same offset. Health experts have argued that this gives Icelandic teenagers social jet lag as the daylight is a misalignment of biological and social time, which consequently results in detrimental health effects. Despite this, however, the government released a statement in 2020 announcing they will not be switching time zones.
History
As Iceland has no international borders nor a railway system, there was no need for a standard time zone across the country. Cities and localities in Iceland were free to pick to observe any time zone they wished, usually based on their mean solar time. This changed at the beginning of the 20th century, with the foundation of Iceland's national telephone company, Landssíminn, in 1906, which allowed for near real-time communication. Accordingly, a law was passed in the Althing on 16 November 1907 stipulating that UTC−01:00 be adopted as the national time zone of Iceland. This was chosen as the majority of Iceland, and particularly the capital Reykjavík, is geographically located within said offset.
Daylight saving time, which moved the clock forward one hour to UTC+00:00, was first attempted between 1917 and 1921. The start and end dates varied, as decided by the government. Daylight saving time was again reintroduced between 1939 and 1968. Between 1941 and 1946, daylight saving time commenced on the first Sunday in March and ended in late October, and between 1947 and 1967 it commenced on the first Sunday in April. In all instances since 1941, daylight saving time commenced at 02:00 and ended at 02:00.
Abolishment of daylight saving time and adoption of UTC+00:00
In 1968, astronomers Traustur Einarsson and Þorsteinn Sæmundsson from the University of Iceland made a proposal to the Althing to abolish daylight saving time and adopt UTC+00:00 year-round. They argued that the observation of daylight saving time confused the scheduling times of aircraft in international flights, caused unnecessary work as all clocks had to be reset, disrupted people's sleep patterns – especially infants – and in general caused confusion, irritation and extra hassle to Icelanders. They were not arguing against UTC+00:00, however, but rather against the moving of clocks back and forth as it created the aforementioned inconveniences. Thus, they proposed observing UTC+00:00 year-round as it would "eliminate all of the above problems, but would still preserve the benefits of summer time", such as being better in sync with Europe – making international trading and telephone calls easier – and allowing for more daylight. The Althing agreed with this proposal, and on 5 April 1968 passed a law stipulating that daylight saving time be abolished and the national time zone be set to UTC+00:00. The law came into effect on 7 April. Since 1994 and most recently in 2019, there have been an increasing number of proposals made to the Althing to reintroduce daylight saving time for a variety of reasons, however all such proposals and resolutions have been rejected.
Proposals to switch to UTC−01:00
In 2014, Björg Þorleifsdóttir, a lecturer at the Faculty of Medicine at the University of Iceland, noted in 2014 that humans' circadian rhythms, which regulate the human sleep–wake cycle, are naturally determined by the solar time of their location. As Iceland does not observe its geographical offset, this leads to disturbed sleep cycles, in turn giving Icelanders – particularly teenagers – social jet lag, resulting in detrimental health effects. In November 2017, a work group under the Ministry of Health (which also included Björg) began conducting research into her claims. In January 2018, they concluded that her claims were factually correct and that Iceland should switch its time zone back to UTC−01:00. Public opinion was also in favour of switching to UTC−01:00: in December 2019, a survey conducted by RÚV showed 56 percent of 1,600 respondents supported the proposed change. However, in 2020, the government released a statement announcing that they would not be switching time zones. They noted that changing time zones would reduce daylight hours during waking hours by 13%, which could lead to a reduction in exercise and outdoor activities.
Geography and solar time
Most of Iceland lies within the geographical UTC−01:00 offset, including the capital Reykjavík, while the westernmost points of Iceland located west of 22.5° West, including Ísafjörður and the Keflavík International Airport, lie within the geographical UTC−02:00 offset. Despite this, Iceland observes UTC+00:00 in order to be in sync with Europe, which results in noon being an hour behind other countries in the same offset, for example 88 minutes behind London. Midnight sun in Iceland can be experienced in summer on the island of Grímsey off the north coast; the remainder of the country, since it lies just south of the polar circle, experiences a twilight period during which the sun sets briefly, but still has around two weeks of continuous daylight during the summer. The difference of longitude between the western (Bjargtangar; 24°32"W) and easternmost (Hvalbakur; 13°16"W) points of Iceland results in a difference of approximately 45 minutes of solar time.
Effects on health
As Iceland observes UTC+00:00 instead of the geographical UTC−01:00 or UTC−02:00, this results in noon being 88 minutes behind other countries in the same offset. Health experts have argued that this gives Icelandic teenagers social jet lag as the daylight is a misalignment of biological and social time, which consequently results in detrimental health effects. As such, several proposals have been made to transition to UTC−01:00 as the standard time zone, all of which have been rejected by the government.
Björg Þorleifsdóttir, a lecturer at the Faculty of Medicine at the University of Iceland, noted in 2014 that humans' circadian rhythms, the natural internal process that regulates the human sleep–wake cycle, is naturally determined by the solar time of where a person lives. But, as Iceland does not observe its geographical position offset, this makes sunrise, noon and sunset happen an hour later than human's biological clocks indicate, which Björg argued leads to disturbed sleep cycles, in-turn giving Icelanders – particularly teenagers – social jet lag, leading to sleep deprivation, slowed reaction times, fatigue, difficulty in concentrating and more frequent mood swings. According to Björg, 35 percent of Icelanders aged between 16 and 19 experience this fatigue. In January 2018, a work group under the Ministry of Health (which also included Björg) further echoed these concerns, when after a study they concluded that Iceland's peculiar position on the geographical time zone map had indeed affected Icelander's health, and in particular led to an "increased risk of illness, poorer schooling, increased depression and fatigue."
The aforementioned claims have not been without criticism however. In 2019, astrophysicist Gunnlaugur Björnsson, while noting the importance of sleep, argued that changing the time zone would not fix sleep deprivation or stop its negative effects, citing "nowhere have I seen research that clock setting affects the progression or recovery of lifestyle diseases and other ailments." He argued that the prevalence of diseases came from lifestyle choices rather than a biological misalignment with a person's social time. He further claimed that "sleep research experts like to state this and seem convinced that this is correct, say 'Studies show that...'. They are usually referring to research into the effects of sleep deprivation, not to the results of systematic research into the effects of timekeeping on physical and mental health." In 2020, the government released a statement announcing they will not be switching time zones. They noted that changing time zones would reduce daylight hours during waking hours by 13%, which could lead to a reduction in exercise and outdoor activities.
Notation
Iceland uses the 24-hour notation in writing, such as on timetables and business hours, but when speaking the 12-hour notation is commonly used.
IANA time zone database
In the IANA time zone database, Iceland is given one zone in the file zone.tab – Atlantic/Reykjavik. "IS" refer's to the country's ISO 3166-1 alpha-2 country code. The table below displays data taken directly from zone.tab of the IANA time zone database. Columns marked with * are the columns from zone.tab itself:
Computers which do not support "Atlantic/Reykjavik" may use the older POSIX syntax: TZ="GMT0".
See also
Time in Europe
List of time zones by country
List of time zones by UTC offset
References
External links
Current time in Iceland at Time.is
Time in Iceland at TimeAndDate.com
Newspaper articles about the time zone of Iceland at the Almanac of the University of Iceland
Geography of Iceland | Time in Iceland | [
"Physics"
] | 2,103 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
67,582,789 | https://en.wikipedia.org/wiki/WASP-103 | WASP-103 is an F-type main-sequence star located 1,800 ± 100 light-years (550 ± 30 parsecs) away in the constellation Hercules. Its surface temperature is (K). The star's concentration of heavy elements is similar to that of the Sun. WASP-103 is slightly younger than the Sun at 4 billion years. The chromospheric activity of the star is elevated due to interaction with the giant planet on a close-in orbit.
A multiplicity survey in 2015 found a suspected stellar companion to WASP-103, at a projected separation of .
Planetary system
In 2014 one super-Jupiter planet, named WASP-103b, was discovered by the transit method. The planet is orbiting its host star in 22 hours and may be close to the limit of tidal disruption. Orbital decay was not detected by 2020. In early 2022, the planet was popularized because of its shape similar to a potato.
The planetary atmosphere contains water, and possibly hydrogen cyanide, titanium(II) oxide, or sodium. The planet has an elevated carbon to oxygen molar fraction of 0.9 or 1.35, therefore it is nearly certain to be a carbon planet.
The planetary equilibrium temperature is , although a big difference exists between the night side and day side. The dayside temperature is , while the night side temperature is .
References
External links
Hercules (constellation)
F-type main-sequence stars
Planetary transit variables
Planetary systems with one confirmed planet
J16371556+0711000 | WASP-103 | [
"Astronomy"
] | 311 | [
"Hercules (constellation)",
"Constellations"
] |
67,583,876 | https://en.wikipedia.org/wiki/NGC%205473 | NGC 5473 is a lenticular galaxy in the constellation Ursa Major. It was discovered on April 14, 1789, by the astronomer William Herschel. Located roughly 85 million light-years (26.2 megaparsecs) away, it is part of a small galaxy group including NGC 5475 and NGC 5485.
References
External links
Ursa Major
5473
Lenticular galaxies | NGC 5473 | [
"Astronomy"
] | 81 | [
"Ursa Major",
"Constellations"
] |
67,584,618 | https://en.wikipedia.org/wiki/Time%20in%20Bulgaria | In Bulgaria, the standard time is Eastern European Time (; EET; UTC+02:00). Daylight saving time, which moves one hour ahead to UTC+03:00 is observed from the last Sunday in March to the last Sunday in October, inline with most EU member states.
History
Bulgaria first observed daylight saving time between 1943 and 1944, and regularly since 1979.
Time notation
Bulgarians commonly use the 24 hour clock. The clock is used exclusively on bus and train timetables.
IANA time zone database
In the IANA time zone database, Bulgaria is given the zone Europe/Sofia:
See also
Time in Europe
List of time zones by country
List of time zones by UTC offset
References
External links
Current time in Bulgaria at Time.is | Time in Bulgaria | [
"Physics"
] | 152 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
67,584,894 | https://en.wikipedia.org/wiki/Constantin%20Corduneanu | Constantin Corduneanu (July 26, 1928 – December 26, 2018) was a Romanian-American mathematician and professor of mathematics at the University of Texas at Arlington. In 2015, he was elected a titular member of the Romanian Academy; he was a corresponding member of the Academy since 1974.
Biography
Corduneanu was born in Potângeni, Iași County, the son of Aglaea and Costache Corduneanu. From 1940 to 1947, he attended military high school in Iași and Predeal. In 1951, he graduated from the Faculty of Sciences of the University of Iași, Department of Mathematics. His teachers there included Alexander Myller, Octav Mayer, , , Ilie Popa, , , , and . Corduneanu received his Ph.D. in 1956 from the University of Iași with thesis Probleme globale pentru ecuațiile diferențiale de ordin I și II written under the supervision of Ilie Popa. The thesis defense the committee was composed of Miron Nicolescu, Grigore Moisil, and .
From 1949 to 1977 he was a faculty member at the University of Iași, advancing in rank to full professor, and serving as Dean of the Faculty of Mathematics (1968–1972) and pro-rector (1972–1973 and 1974–1977). He also held faculty positions at the Gheorghe Asachi Technical University of Iași and at the University of Suceava, where he served as rector from 1966 to 1968.
In 1977, Corduneanu decided to leave Romania. He first went to Italy, where he taught some courses at the International Centre for Theoretical Physics in Trieste. In January 1978, he emigrated to the United States, and secured a teaching position at the University of Rhode Island (where he had been a visiting professor in 1967–1968 and 1973–1974). After spending a year as visiting professor at the University of Tennessee at Knoxville, he became a tenured professor in the fall of 1979 at the University of Texas at Arlington, where he taught until his retirement in 1996. He died at Medical City Arlington in 2018, at age 90.
A Festschrift in his honor, titled Mathematical Analysis With Applications, was published in 2018.
Books
References
External links
1928 births
2018 deaths
People from Iași County
Romanian mathematicians
Mathematical analysts
Alexandru Ioan Cuza University alumni
Academic staff of Alexandru Ioan Cuza University
Academic staff of the Gheorghe Asachi Technical University of Iași
Rectors of universities in Romania
Titular members of the Romanian Academy
Romanian emigrants to the United States
University of Texas at Arlington faculty
20th-century American mathematicians
21st-century American mathematicians
Romanian expatriates in Italy | Constantin Corduneanu | [
"Mathematics"
] | 551 | [
"Mathematical analysis",
"Mathematical analysts"
] |
67,588,066 | https://en.wikipedia.org/wiki/Acinetospora%20crinita | Acinetospora crinita is a species of brown alga in the family Acinetosporaceae. It is found in the temperate northeastern Atlantic Ocean and the Mediterranean Sea.
Description
Acinetospora crinita forms slender, irregularly branched filaments some 25 to 35 μm in diameter. These consist of strands of cells, each up to three times longer than they are broad, of a pale brown or yellowish-brown colour. Each cell contains several disc-shaped chloroplasts and a pyrenoid. The tips of the filaments are rounded; the filaments are often tangled with other algae forming bushy tufts which can grow to a length of several metres. This alga can be distinguished from other similar species by the branches growing perpendicularly from the filaments, and often emerging from the middle of a cell.
Distribution and habitat
Acinetospora crinita occurs in the temperate northeastern Atlantic Ocean and the Mediterranean Sea. It is also considered to be part of a cosmopolitan species complex, being reported from Bermuda, the Caribbean Sea, the Pacific Ocean and elsewhere, and has been described as "enigmatic". Where it does grow, it sometimes consists of fragments of as many as thirty different species intermingled, with the different strains thriving in varying conditions and at different times of year. It forms a more or less complete covering of filamentous algae over the rock, detritus, living animals and sea grasses on the seabed in its habitat; its depth range is .
Biology
Like other brown algae, Acinetospora crinita uses chlorophyll, fucoxanthin and other pigments to fix carbon dioxide by photosynthesis. The reproductive system is very complex and has not been fully elucidated; the method used can vary with the region, the time of year and the population concerned. Several stages are involved and at least five reproductive structures have been identified. The sporangia (reproductive organs) are inserted perpendicularly to the filaments. The alga can also reproduce asexually by fragmentation.
Acinetospora crinita and other filamentous algae grow vigorously in spring and summer, covering the seabed and tending to swamp other organisms, reducing their ability to filter feed and sometimes killing them. The algae thrive with warm weather, calm seas and high levels of nutrients in the water. They are eaten by herbivorous fish, but grow at a faster rate than they can be consumed.
References
External links
Ectocarpales
Taxa named by Dugald Carmichael
Biota of the Atlantic Ocean | Acinetospora crinita | [
"Biology"
] | 537 | [
"Biota of the Atlantic Ocean",
"Biota by sea or ocean"
] |
67,588,825 | https://en.wikipedia.org/wiki/Aquamyces | Aquamyces is a genus of fungi belonging to the family Aquamycetaceae.
Species:
Aquamyces chlorogonii (Serbinow) Letcher
References
Chytridiomycota
Chytridiomycota genera | Aquamyces | [
"Biology"
] | 53 | [
"Fungus stubs",
"Fungi"
] |
67,588,953 | https://en.wikipedia.org/wiki/Boothiomyces | Boothiomyces is a genus of fungi belonging to the family Terramycetaceae.
The genus has almost cosmopolitan distribution.
Species:
Boothiomyces macroporosus (Karling) Letcher
References
Chytridiomycota
Chytridiomycota genera | Boothiomyces | [
"Biology"
] | 60 | [
"Fungus stubs",
"Fungi"
] |
64,611,260 | https://en.wikipedia.org/wiki/Randonautica | Randonautica (a portmanteau of "random" + "nautica") is an app launched on February 22, 2020 founded by Auburn Salcedo and Joshua Lengfelder. It randomly generates coordinates that enable the user to explore their local area and report on their findings. According to its creators, the app is "an attractor of strange things," letting one choose specific coordinates based on a certain theme. It gained controversy after a report of two teenagers coincidentally finding a corpse while using the app.
Overview
The app, which creators claim to be inspired by chaos theory and Guy Debord's Theory of the Dérive, offers its users three types of coordinates to choose from: an attractor, a void, or an anomaly. The app has a cult following on YouTube and TikTok and there is a subreddit made by the creators for users of the app.
History
29-year-old circus performer Joshua Lengfelder discovered a bot called Fatum Project in a fringe science chat group on Telegram in January 2019. According to The New York Times, "He absorbed the project’s theories about how random exploration could break people out of their predetermined realities, and how people could influence random outcomes with their minds." Lengfelder then created a Telegram bot using Fatum Project's code, generating coordinates. He then created the subreddit r/randonauts in March. In October, developer Simon Nishi McCorkindale made the bot's webpage.
With the help of Auburn Salcedo, chief executive of a TV agency, both created Randonauts LLC. Salcedo became the chief operating officer while Lengfelder was the CEO. The app, called Randonautica, was launched on February 22, 2020. Later the same year the app and back-end got completely overhauled by a new team of developers and got a more visual and friendlier design and logo.
In April 2022 Lengfelder exited Randonauts LLC and Auburn Salcedo became CEO.
Reception
The app has as many as 10.8 million users as of July 2020, gaining popularity amid the COVID-19 pandemic in the United States as restrictions have been lightened. Emma Chamberlain made a YouTube video about the app that helped increase its following. i-D reported that the hashtag #randonautica has gained 176.5 million views on TikTok, although it has not marketed itself yet.
Controversy
With the app's popularity users started reporting coincidences which many find unsettling. The majority of reports were from TikTok and Reddit, as well as Telegram.
The most notable controversy involved a group of people heading to a beach in Duwamish Head, Puget Sound, West Seattle per the app, where they found a bag with two dead bodies, a 27-year-old male and a 36-year-old female, as reported by the Seattle Police homicide detectives. In August 2020 police arrested and charged their landlord, Michael Lee Dudley, in connection with the murders. In March 2021, Dudley was denied bail while other people were under suspicion of aiding Dudley in the dismemberment and disposal of the bodies, but no one else had been charged. This has caused speculation that the app has an intended, puzzle-like theme, however Lengfelder stated that it is "a shocking coincidence." Salcedo called the videos fake, and that "It’s so hard to manage, because people are really taking creative liberties after seeing how much traction the app is getting in that fear factor." In 2022, Michael Dudley was convicted of second degree murder for killing both victims, who were identified as Jessica Lewis and Austin Wenner. He was sentenced to 46 years in prison the following year.
In their questions page, Randonautica's creators have said that if the app generates coordinates inside a private property, it is a violation of their terms and conditions to trespass. In addition, Randonautica has also received allegations that the app is used for human trafficking, which its creators have denied, saying that data collected by the app are anonymous. It also ensured that the app is not designed to violate religious customs, saying that "the app is simply a tool. Just as a knife can be used either to prepare dinner or to cut somebody."
See also
Geocaching
Geohashing, another game of visiting random coordinates
Pokémon Go, an app with similar controversies
Ingress, as above
References
External links
r/randonauts, a subreddit for Randonauts
The relevant randomness rig at Australian National University
Mobile applications
Geographic data and information
Orienteering | Randonautica | [
"Technology"
] | 960 | [
"Geographic data and information",
"Data"
] |
64,611,466 | https://en.wikipedia.org/wiki/2.5D%20integrated%20circuit | A 2.5D integrated circuit (2.5D IC) is an advanced packaging technique that combines multiple integrated circuit dies in a single package without stacking them into a three-dimensional integrated circuit (3D-IC) with through-silicon vias (TSVs). The term "2.5D" originated when 3D-ICs with TSVs were quite new and still very difficult. Chip designers realized that many of the advantages of 3D integration could be approximated by placing bare dies side by side on an interposer instead of stacking them vertically. If the pitch is very fine and the interconnect very short, the assembly can be packaged as a single component with better size, weight, and power characteristics than a comparable 2D circuit board assembly. This half-way 3D integration was facetiously named "2.5D" and the name stuck.
Since then, 2.5D has proven to be far more than just "half-way to 3D."
Some benefits:
An interposer can support heterogeneous integration – that is, dies of different pitch, size, material, and process node.
Placing dies side by side instead of stacking them reduces heat buildup.
Upgrading or modifying a 2.5D assembly is as easy as swapping in a new component and revamping the interposer to suit; much faster and simpler than reworking an entire 3D-IC or System-on-Chip (SoC).
Some sophisticated 2.5D assemblies even incorporate TSVs and 3D components. Several foundries now support 2.5D packaging.
The success of 2.5D assembly has given rise to "chiplets" – small, functional circuit blocks designed to be combined in mix-and-match fashion on interposers. Several high-end products already take advantage of these LEGO-style chiplets; some experts predict the emergence of an industry-wide chiplet ecosystem. Interposers can be larger than the reticle size which is the maximum area that can be projected by a photolithography scanner or stepper.
References
Integrated circuits | 2.5D integrated circuit | [
"Technology",
"Engineering"
] | 430 | [
"Computer engineering",
"Integrated circuits"
] |
64,612,080 | https://en.wikipedia.org/wiki/Einstein%27s%20Unfinished%20Symphony | Einstein's Unfinished Symphony: Listening to the Sounds of Space-Time is a 2000 non-fiction book by Marcia Bartusiak about the preliminary work preceding operational efforts to detect the gravitational waves predicted by Einstein's theory of general relativity. She tells the story of LIGO's two gravitational-wave observatories in Louisiana and Washington State, with some mention of other such observatories in Italy, Germany, Japan, and Australia, and the scientists and scientific considerations involved. Initial LIGO operations between 2002 and 2010 did not detect any gravitational waves. After technical enhancements, gravitational waves were first detected in 2016. After the detection, Bartusiak wrote an updated version entitled Einstein's Unfinished Symphony: The Story of a Gamble, Two Black Holes, and a New Age of Astronomy published in 2017 by Yale University Press.
Reception
For her 2000 book, Bartusiak won the 2001 American Institute of Physics Science Writing Award to a Journalist.
References
External links
2000 non-fiction books
Science books
Books about the history of physics
Astronomy books | Einstein's Unfinished Symphony | [
"Astronomy"
] | 212 | [
"Astronomy books",
"Astronomy book stubs",
"Works about astronomy",
"Astronomy stubs"
] |
64,614,674 | https://en.wikipedia.org/wiki/Daimler%20Motor%20Lastwagen | The Daimler Motor-Lastwagen is the world's first truck, manufactured in the year 1896 by Daimler Motoren Gesellschaft and designed by Gottlieb Daimler.
History
In 1896, Gottlieb Daimler and Wilhelm Maybach began developing a truck with a 1.06-liter two-cylinder four-stroke engine built into the rear, which developed 4 hp (2.9 kW ). The one with hot-tube ignition and injection nozzle carburetor equipped engine was the first prototype built yet behind the rear axle and driving the rear wheels through a four-speed belt drive. The car had turntable steering and a manually operated block brake that acted on the iron tires on the rear wheels. There was also a foot-operated shoe brake on the countershaft. The vehicle was 4.5 m long and 1.5 m wide, the payload was given as 1500 kg, and the top speed was 12 kmph. Its purchase price was 5,200 marks.
On 1 October 1896, Daimler sold the first truck ("Order No. 81") to the British Motor Syndicate in London. In this model, the motor had been enlarged to 1.53 liters with 6 HP (4.4 kW), was installed under the driver's seat. In the same year, Daimler-Motoren-Gesellschaft was the first vehicle manufacturer in the world to launch a model range of various trucks that were available in four different power levels: 2.9 kW, 4.4 kW, 5.9 kW and 7.4 kW. The payloads ranged from 1.2 tons to 5 tons.
According to documents from Daimler were delivered by January 1899 "ten load and thirteen Bierwagen". Customers included the Paul von Maur freight forwarder in Stuttgart and the Bohemian brewery in Berlin, which used the Daimler motor truck as a "beer wear truck".
References
Sources
Further reading
Mercedes-Benz Group
History of transport
Trucks | Daimler Motor Lastwagen | [
"Physics"
] | 405 | [
"Physical systems",
"Transport",
"History of transport"
] |
64,614,919 | https://en.wikipedia.org/wiki/Cloud-native%20network%20function | A cloud-native network function (CNF) is a software-implementation of a function, or application, traditionally performed on a physical device, but which runs inside Linux containers (typically orchestrated by Kubernetes). The features that differ CNFs from VNFs (virtualized network functions), one of the components of network function virtualization, is the approach in their orchestration.
In ETSI NFV standards, the cloud-native network functions are a particular type of virtualized network functions and are orchestrated as VNFs, i.e. using the ETSI NFV MANO architecture and technology-agnostic descriptors (e.g. TOSCA, YANG). In that case, the upper layers of the ETSI NFV MANO architecture (i.e. the NFVO and VNFM) cooperate with a container infrastructure service management (CISM) function that is typically implemented using cloud-native orchestration solutions (e.g. Kubernetes).
The characteristics of cloud-native network functions are:
containerized microservices that communicate with each-other via standardized RESTful APIs
small performance footprint, with the ability to scale horizontally
independence of guest operating system, since CNFs operate as containers
lifecycle manageable by Kubernetes, using container images registries such as OCI Docker, and OS container runtime.
Relation to network function virtualization
These characteristics address many of the common issues found with the first generation of VNFs, by incorporating many of the innovations deployed commonly in the internet infrastructure. These include auto-scaling, supporting a continuous delivery/DevOps deployment model, and efficiency gains by sharing common services across platforms. Through service discovery and orchestration, a system based on CNFs will be more resilient to node failure. A specification of criteria to classify and characterize cloud-native VNF implementations can be found in ETSI GS NFV-EVE 011.
Cloud Native Computing Foundation
The Linux Foundation backed Cloud Native Computing Foundation project is actively supporting companies in contributing to open-source projects like Kubernetes or Prometheus, upon which Cloud Native Network Functions can be based on. The CNCF project also created a CNF Testbed, in order to facilitate a common test-ground for various cloud-native network functions.
References
11. Cloud Native Computing Foundation, (http://www.cncf.io)
Cloud infrastructure
Network topology
Virtualization software | Cloud-native network function | [
"Mathematics",
"Technology"
] | 509 | [
"Network topology",
"Cloud infrastructure",
"Topology",
"IT infrastructure"
] |
64,616,308 | https://en.wikipedia.org/wiki/Cyparissus%20%28Vignali%29 | Cyparissus is a 1620s Baroque painting on a mythological subject from Ovid's Metamorphoses by the Italian painter Jacopo Vignali. It is on display in the Musée des Beaux-Arts of Strasbourg, France, to which it had been donated by the collectors Othon Kaufmann and François Schlageter in 1994. Its inventory number is 994-1-8, or 44.994.1.8.
The painting depicts the young Cyparissus, mourning his pet deer, that he had mistakenly killed with his own bow and arrow. The young boy's pain is amplified beyond the description given by Ovid, and possibly inspired by a 1624 Venetian edition of Giovanni Andrea dell' Anguillara's Metamorfosi ridotte in ottava rima, in which the tearful aspect of the story is emphasized. It is one of the very few profane paintings by Vignali.
References
External links
Cyparissus , presentation on the museum's website
Paintings in the Musée des Beaux-Arts de Strasbourg
1620s paintings
Mythological paintings
Baroque paintings
Italian paintings
Paintings about death
Human–animal interaction
Oil on canvas paintings
Paintings based on Metamorphoses | Cyparissus (Vignali) | [
"Biology"
] | 251 | [
"Human–animal interaction",
"Animals",
"Humans and other species"
] |
64,618,361 | https://en.wikipedia.org/wiki/Italian%20Federation%20of%20Chemical%20and%20Allied%20Workers | The Italian Federation of Chemical and Allied Workers (, FILCEA) was a trade union representing chemical and some manufacturing workers in Italy.
The union was founded in December 1968, when the Italian Federation of Chemical and Oil Workers merged with the Federation of Glass and Ceramics. Like its predecessors, it affiliated to the Italian General Confederation of Labour.
By 1998, the union had 128,566 members, of whom 90% worked in the chemical industry, and most of the remainder in glass and ceramics. In February 2006, the union merged with the National Federation of Energy Workers, to form the Italian Federation of Chemical, Energy and Manufacturing Workers.
General Secretaries
1968: Giovan Battista Trespidi
1977: Fausto Vigevani
1981: Ettore Masucci
1986: Giuliano Cazzola
1988: Sergio Cofferati
1990: Franco Chiriaco
2000: Edoardo Guarino
2002: Mauro Guzzonato
2003: Giacomo Berni
2004: Alberto Morselli
References
Chemical industry in Italy
Chemical industry trade unions
Trade unions established in 1968
Trade unions disestablished in 2006
Trade unions in Italy | Italian Federation of Chemical and Allied Workers | [
"Chemistry"
] | 223 | [
"Chemical industry trade unions"
] |
64,618,645 | https://en.wikipedia.org/wiki/Billie%20J.%20Swalla | Billie J. Swalla is a professor of biology at the University of Washington. She was the first female director of Friday Harbor Laboratories, where she worked from 2012 to 2019. Her lab investigates the evolution of chordates by comparative genetic and phylogenetic analysis of animal taxa.
Education
Billie Swalla earned her Bachelor of Science in Zoology from the University of Iowa in 1980. She earned a Master of Science there, with a thesis on chicken egg development in 1983. She then took an Embryology course at the Marine Biological Lab in Woods Hole, Massachusetts. She earned her PhD in Biology, also at Iowa, on chicken egg development in 1988. She became a Post-Doctoral Fellow with William R. Jeffery studying gene expression during ascidian egg development. In 1988, Swalla and Jeffery traveled to the Station Biologique in Roscoff, France, to study the evolution and development of ascidians. Shortly after, Swalla won a Post-Doctoral Fellowship from the National Institutes of Health to study developmental biology at the Bodega Marine Laboratory at the University of California.
In 1994, Swalla worked as an assistant professor of Biology at Vanderbilt University for three years. She then worked as an assistant professor at Pennsylvania State University from 1997 to 1999 before settling at the University of Washington.
Research
Swalla's research is on molecular analysis of invertebrate evolution and development, and ranges from studying hemichordates to chordates to ctenophores. By studying hemichordates, she examines the genomics of chordate development to understand the evolution of the chordate body plan. Her work on other animal taxa, such as echinoderms and hemichordates, provides comparisons in gene expression and body plan development.
Swalla has developed a theory on physical features of the chordate ancestor. While gill slits are homologous between hemichordates and chordates, gill bars are not. She is studying the evolutionary history of other ancestral chordate features across taxa. She is looking into the phylogenetic diversity of hemichordates and how the evolution of a nervous system differs between species. Having studied the genetics of chordate development in ascidians, she is examining the evolution of coloniality and social dynamics of ascidian species.
Leadership
Swalla has served as Program Officer for the Division of Developmental and Cell Biology within the Society for Integrative and Comparative Biology (1996-1999), Chairman of the Electorate Nominating Committee for Biological Sciences (2001-2004), President of the Society for Integrative and Comparative Biology (2013-2015), and President of the PanAm Society of EvoDevo Biology (2017-2019). She was also the first female director of Friday Harbor Laboratories (FHL), from 2012–2019.
As director of FHL, Swalla established a Marine Biology major for University of Washington students, and fellowships and professorships to bring faculty to FHL. She led fundraising efforts of over $10,000,000 and created a Fire Mitigation plan to protect the campus from wildfires.
Outreach and inclusion
Swalla has emphasized outreach and inclusion. As director, she expanded a Research Experience for Undergraduates (REU) program through the National Science Foundation specifically for Friday Harbor Laboratories, to provide underrepresented students the chance to engage in scientific research over a summer. She had regular communication with the communities living around FHL on land conservation efforts and the marine habitats surrounding the residents, and shared their research through Tide Bites, a monthly publication available both online and in print for the communities around FHL. Swalla is a member of the Society for Advancing Hispanics/Chicanos and Native Americans in Science (SACNAS) and has worked to increase representation in the sciences. She has mentored REU students, taught sessions at local elementary schools, high schools, and community colleges, and in international workshops to multinational audiences.
Publications
References
Year of birth missing (living people)
Living people
Phylogenetics researchers
20th-century American zoologists
American women zoologists
University of Iowa alumni
Pennsylvania State University faculty
Vanderbilt University faculty
University of Washington faculty | Billie J. Swalla | [
"Biology"
] | 830 | [
"Phylogenetics",
"Phylogenetics researchers"
] |
64,619,165 | https://en.wikipedia.org/wiki/Thomas%20H.%20Epps%20III | Thomas H. Epps, III is an American chemist and the Thomas & Kipp Gutshall Professor of Chemical & Biomolecular Engineering at the University of Delaware. He has a joint appointment in Materials Science & Engineering, and an affiliated appointment in Biomedical Engineering. He serves as the director of the Center for Research in Soft Matter & Polymers, the director of the Center for Hybrid, Active, and Responsive Materials (a National Science Foundation, Materials Research Science and Engineering Center), and the co-director of the Center for Plastics Innovations (A Department of Energy, Energy Frontiers Research Center). His research considers the design, synthesis, characterization, and application of nanostructure-containing polymers related to biobased materials, drug delivery, alternative energy (batteries), nanotemplating, and composite-based personal-protective equipment. He is also the co-founder of Lignolix, which is focused on the valorization of biomass waste.
Early life and education
Epps was born to Ruth Epps, a professor of accounting at Virginia Union University and Virginia Commonwealth University, and Thomas H. Epps, Jr, professor of chemistry at Virginia State University. He grew up in Chesterfield County, Virginia. Epps completed his undergraduate degree at the Massachusetts Institute of Technology. He was one of the first people to be selected as an American Chemical Society Minority Scholar. He remained there for his graduate studies, completing a master's degree in chemical engineering (Practice School) in 1999 before moving to the University of Minnesota for his doctorate. At the University of Minnesota he worked under the supervision of Frank S. Bates. After completing his PhD research, Epps joined the National Institute of Standards and Technology as a National Research Council Fellow in the Polymers Division.
Research and career
In the summer of 2006 Epps joined the University of Delaware. Here his research considers nanostructured assemblies of polymers for a variety of applications. In particular, he has focused on block copolymers; polymers which are composed of two or more chemically dissimilar units. Specifically, Epps develops block copolymers that can assemble into nano-scale structures with carefully controlled molecular shapes, sizes and orientations.
By manipulating the regions between blocks to control phase transitions and intermolecular packing, Epps has studied the interfacial interactions of tapered block copolymers. He also pioneered the development of gradient substrates and free surfaces the deposition of block copolymer thin films. Epps showed that self-assembled monolayers of chlorosilane used in combination with flow-coating and solvent vapour gradients can result in nanostructures with precise optical and electronic properties. Epps spent 2013 as a Martin Luther King Jr. Fellow at Massachusetts Institute of Technology, where he worked with Timothy M. Swager on the self-assembly of polymers.
In 2016 he demonstrated it was possible to synthesize novel polymers with tuneable thermal properties through the use of waste from the pulp and paper business. He was awarded a $4 million grant from the National Science Foundation to develop new synthesis pathways that allow the development of novel materials from lignin. When talking about the new programme, Epps said "one of the big problems that we want to address is sustainability ... not just thinking about whether we can make new polymers or catalysts from biomass, but understanding the impact of these polymers on the environment, in terms of toxicity and in terms of the resources,". He went on to found Lignolix, a spin-out company that focuses on making sustainable materials from renewable biomass. Lignolix won the 2019 University of Delaware FastPass competition.
Epps has realised polymer-based for lithium-ion batteries, where the polymer serves the role of the liquid electrolyte. The polymer prevents calcification of the positive and negative electrodes in the battery, which can otherwise cause sparks and fires. Polymers also permit quick charging/discharging due to the formation of small channels that allow fast ion transport.
In 2020 Epps and LaShanda Korley were announced as the directors of the United States Department of Energy Center for Plastics Innovation. The $11.65 million center brings together researchers from the University of Delaware, University of Chicago, University of Massachusetts Amherst and Oak Ridge National Laboratory to upcycle plastic waste. Also in 2020, Epps was announced as the director of the University of Delaware's Center for Hybrid, Active, and Responsive Materials (UD CHARM), a National Science Foundation Materials Research Science and Engineering Center. The $6.5 million center brings together researchers from University of Delaware, University of Pennsylvania and the National Institute of Standards & Technology.
Awards and honours
2021 National Academy of Inventors Fellow
2021 American Institute for Medical and Biological Engineering Fellow
2020 National Organization for the Professional Advancement of Black Chemists and Chemical Engineers Percy L. Julian Award
2020 American Chemical Society Prominent African American Chemists
2018 Elected fellow of the Royal Society of Chemistry
2017 Elected fellow of the American Physical Society
2016 American Physical Society John H. Dillon Medal
2015 American Institute of Chemical Engineers Owens Corning Young Investigator Award
2014 Kavli Foundation Fellow of the National Academies of Sciences, Engineering, and Medicine
2014 Sigma Xi Young Investigator Award
2012 Massachusetts Institute of Technology Martin Luther King Jr. Visiting Professor
2010 DuPont Professor Award
2009 Presidential Early Career Award for Scientists and Engineers
Select publications
External links
Oral history interview transcript with Thomas H. Epps III on 28 July 2020, American Institute of Physics, Niels Bohr Library & Archives
References
African-American chemists
MIT School of Engineering alumni
People from Chesterfield County, Virginia
University of Minnesota alumni
American organic chemists
University of Delaware faculty
Minnesota CEMS
Year of birth missing (living people)
Living people
Fellows of the National Academy of Inventors
21st-century African-American scientists
21st-century African-American academics
21st-century American academics
Fellows of the American Physical Society
African-American physicists
Recipients of the Presidential Early Career Award for Scientists and Engineers | Thomas H. Epps III | [
"Chemistry"
] | 1,205 | [
"Organic chemists",
"American organic chemists"
] |
64,619,822 | https://en.wikipedia.org/wiki/Space%27s%20Deepest%20Secrets | Space's Deepest Secrets is a documentary science television series narrated by David O'Brien. Aired by the Science Channel, it premiered on April 26, 2016.
According to the Science Channel, "Space's Deepest Secrets shares the stories of the men and women who pushed their ingenuity and curiosity beyond the limits to uncover some of the most groundbreaking findings in the history of space exploration."
Episode list
Season 1 (2016)
Season 2 (2017)
Season 3 (2017)
Season 4 (2018)
Season 5 (2018)
Season 6 (2019)
Season 7 (2020)
Season 8 (2021)
References
External links
sciencechannel.com Space′s Deepest Secrets
trakt.tv Space's Deepest Secrets
tvmaze.com Space's Deepest Secrets – Episode Guide
2016 American television series debuts
2010s American documentary television series
Documentary television series about astronomy
Science Channel original programming | Space's Deepest Secrets | [
"Astronomy"
] | 177 | [
"Documentary television series about astronomy",
"Works about astronomy"
] |
64,620,077 | https://en.wikipedia.org/wiki/Closed%20graph%20theorem%20%28functional%20analysis%29 | In mathematics, particularly in functional analysis, the closed graph theorem is a result connecting the continuity of a linear operator to a topological property of their graph. Precisely, the theorem states that a linear operator between two Banach spaces is continuous if and only if the graph of the operator is closed (such an operator is called a closed linear operator; see also closed graph property).
One of important questions in functional analysis is the question of the continuity (or boundedness) of a given linear operator. The closed graph theorem gives one answer to that question.
Explanation
Let be a linear operator between Banach spaces (or more generally Fréchet spaces). Then the continuity of means that for each convergent sequence . On the other hand, the closedness of the graph of means that for each convergent sequence such that , we have . Hence, the closed graph theorem says that in order to check the continuity of , one can show under the additional assumption that is convergent.
In fact, for the graph of T to be closed, it is enough that if , then . Indeed, assuming that condition holds, if , then and . Thus, ; i.e., is in the graph of T.
Note, to check the closedness of a graph, it’s not even necessary to use the norm topology: if the graph of T is closed in some topology coarser than the norm topology, then it is closed in the norm topology. In practice, this works like this: T is some operator on some function space. One shows T is continuous with respect to the distribution topology; thus, the graph is closed in that topology, which implies closedness in the norm topology and then T is a bounded by the closed graph theorem (when the theorem applies). See for an explicit example.
Statement
The usual proof of the closed graph theorem employs the open mapping theorem. It simply uses a general recipe of obtaining the closed graph theorem from the open mapping theorem; see (this deduction is formal and does not use linearity; the linearity is needed to appeal to the open mapping theorem which relies on the linearity.)
In fact, the open mapping theorem can in turn be deduced from the closed graph theorem as follows. As noted in , it is enough to prove the open mapping theorem for a continuous linear operator that is bijective (not just surjective). Let T be such an operator. Then by continuity, the graph of T is closed. Then under . Hence, by the closed graph theorem, is continuous; i.e., T is an open mapping.
Since the closed graph theorem is equivalent to the open mapping theorem, one knows that the theorem fails without the completeness assumption. But more concretely, an operator with closed graph that is not bounded (see unbounded operator) exists and thus serves as a counterexample.
Example
The Hausdorff–Young inequality says that the Fourier transformation is a well-defined bounded operator with operator norm one when . This result is usually proved using the Riesz–Thorin interpolation theorem and is highly nontrivial. The closed graph theorem can be used to prove a soft version of this result; i.e., the Fourier transformation is a bounded operator with the unknown operator norm.
Here is how the argument would go. Let T denote the Fourier transformation. First we show is a continuous linear operator for Z = the space of tempered distributions on . Second, we note that T maps the space of Schwarz functions to itself (in short, because smoothness and rapid decay transform to rapid decay and smoothness, respectively). This implies that the graph of T is contained in and is defined but with unknown bounds. Since is continuous, the graph of is closed in the distribution topology; thus in the norm topology. Finally, by the closed graph theorem, is a bounded operator.
Generalization
Complete metrizable codomain
The closed graph theorem can be generalized from Banach spaces to more abstract topological vector spaces in the following ways.
Between F-spaces
There are versions that does not require to be locally convex.
This theorem is restated and extend it with some conditions that can be used to determine if a graph is closed:
Complete pseudometrizable codomain
Every metrizable topological space is pseudometrizable. A pseudometrizable space is metrizable if and only if it is Hausdorff.
Codomain not complete or (pseudo) metrizable
An even more general version of the closed graph theorem is
Borel graph theorem
The Borel graph theorem, proved by L. Schwartz, shows that the closed graph theorem is valid for linear maps defined on and valued in most spaces encountered in analysis.
Recall that a topological space is called a Polish space if it is a separable complete metrizable space and that a Souslin space is the continuous image of a Polish space. The weak dual of a separable Fréchet space and the strong dual of a separable Fréchet-Montel space are Souslin spaces. Also, the space of distributions and all Lp-spaces over open subsets of Euclidean space as well as many other spaces that occur in analysis are Souslin spaces.
The Borel graph theorem states:
An improvement upon this theorem, proved by A. Martineau, uses K-analytic spaces.
A topological space is called a if it is the countable intersection of countable unions of compact sets.
A Hausdorff topological space is called K-analytic if it is the continuous image of a space (that is, if there is a space and a continuous map of onto ).
Every compact set is K-analytic so that there are non-separable K-analytic spaces. Also, every Polish, Souslin, and reflexive Fréchet space is K-analytic as is the weak dual of a Frechet space.
The generalized Borel graph theorem states:
Related results
If is closed linear operator from a Hausdorff locally convex TVS into a Hausdorff finite-dimensional TVS then is continuous.
See also
References
Notes
Bibliography
Theorems in functional analysis | Closed graph theorem (functional analysis) | [
"Mathematics"
] | 1,240 | [
"Theorems in mathematical analysis",
"Theorems in functional analysis"
] |
64,621,169 | https://en.wikipedia.org/wiki/PM%20Sayeed%20Marine%20Birds%20Conservation%20Reserve | PM Sayeed Marine Birds Conservation Reserve is the first protected area for marine birds in India. It is located in the Indian Union Territory of Lakshadweep. It was formed in 2020. It covers an area of 62 km2.
The PM Sayeed Marine Birds Conservation Reserve will be home to four species of pelagic seabirds – the Greater crested tern, Lesser crested tern, Sooty tern, and the Brown noddy.
See also
Dr. K.K. Mohammed Koya Sea Cucumber Conservation Reserve
Pichavaram
Karimpuzha Wildlife Sanctuary
References
Bird sanctuaries of India
Tourism in Lakshadweep
Nature conservation in India
Biodiversity
2020 establishments in Lakshadweep | PM Sayeed Marine Birds Conservation Reserve | [
"Biology"
] | 147 | [
"Biodiversity"
] |
53,489,871 | https://en.wikipedia.org/wiki/Software%20testing%20tactics | This article discusses a set of tactics useful in software testing. It is intended as a comprehensive list of tactical approaches to software quality assurance (more widely colloquially known as quality assurance (traditionally called by the acronym "QA")) and general application of the test method (usually just called "testing" or sometimes "developer testing").
Installation testing
An installation test assures that the system is installed correctly and working at actual customer's hardware.
The box approach
Software testing methods are traditionally divided into white- and black-box testing. These two approaches are used to describe the point of view that a test engineer takes when designing test cases.
White-box testing
White-box testing (also known as clear box testing, glass box testing, transparent box testing and structural testing, by seeing the source code) tests internal structures or workings of a program, as opposed to the functionality exposed to the end-user. In white-box testing an internal perspective of the system, as well as programming skills, are used to design test cases. The tester chooses inputs to exercise paths through the code and determine the appropriate outputs. This is analogous to testing nodes in a circuit, e.g. in-circuit testing (ICT).
While white-box testing can be applied at the unit, integration and system levels of the software testing process, it is usually done at the unit level. It can test paths within a unit, paths between units during integration, and between subsystems during a system–level test. Though this method of test design can uncover many errors or problems, it might not detect unimplemented parts of the specification or missing requirements.
Techniques used in white-box testing include:
API testing – testing of the application using public and private APIs (application programming interfaces)
Code coverage – creating tests to satisfy some criteria of code coverage (e.g., the test designer can create tests to cause all statements in the program to be executed at least once)
Fault injection methods – intentionally introducing faults to gauge the efficacy of testing strategies
Mutation testing methods
Static testing methods
Code coverage tools can evaluate the completeness of a test suite that was created with any method, including black-box testing. This allows the software team to examine parts of a system that are rarely tested and ensures that the most important function points have been tested. Code coverage as a software metric can be reported as a percentage for:
Function coverage, which reports on functions executed
Statement coverage, which reports on the number of lines executed to complete the test
Decision coverage, which reports on whether both the True and the False branch of a given test has been executed
100% statement coverage ensures that all code paths or branches (in terms of control flow) are executed at least once. This is helpful in ensuring correct functionality, but not sufficient since the same code may process different inputs correctly or incorrectly.
Black-box testing
Black-box testing treats the software as a "black box", examining functionality without any knowledge of internal implementation, without seeing the source code. The testers are only aware of what the software is supposed to do, not how it does it. Black-box testing methods include: equivalence partitioning, boundary value analysis, all-pairs testing, state transition tables, decision table testing, fuzz testing, model-based testing, use case testing, exploratory testing and specification-based testing.
Specification-based testing aims to test the functionality of software according to the applicable requirements. This level of testing usually requires thorough test cases to be provided to the tester, who then can simply verify that for a given input, the output value (or behavior), either "is" or "is not" the same as the expected value specified in the test case.
Test cases are built around specifications and requirements, i.e., what the application is supposed to do. It uses external descriptions of the software, including specifications, requirements, and designs to derive test cases. These tests can be functional or non-functional, though usually functional.
Specification-based testing may be necessary to assure correct functionality, but it is insufficient to guard against complex or high-risk situations.
One advantage of the black box technique is that no programming knowledge is required. Whatever biases the programmers may have had, the tester likely has a different set and may emphasize different areas of functionality. On the other hand, black-box testing has been said to be "like a walk in a dark labyrinth without a flashlight." Because they do not examine the source code, there are situations when a tester writes many test cases to check something that could have been tested by only one test case, or leaves some parts of the program untested.
This method of test can be applied to all levels of software testing: unit, integration, system and acceptance. It typically comprises most if not all testing at higher levels, but can also dominate unit testing as well.
Visual testing
The aim of visual testing is to provide developers with the ability to examine what was happening at the point of software failure by presenting the data in such a way that the developer can easily find the information she or he requires, and the information is expressed clearly.
At the core of visual testing is the idea that showing someone a problem (or a test failure), rather than just describing it, greatly increases clarity and understanding. Visual testing therefore requires the recording of the entire test process – capturing everything that occurs on the test system in video format. Output videos are supplemented by real-time tester input via picture-in-a-picture webcam and audio commentary from microphones.
Visual testing provides a number of advantages. The quality of communication is increased drastically because testers can show the problem (and the events leading up to it) to the developer as opposed to just describing it and the need to replicate test failures will cease to exist in many cases. The developer will have all the evidence he or she requires of a test failure and can instead focus on the cause of the fault and how it should be fixed.
Visual testing is particularly well-suited for environments that deploy agile methods in their development of software, since agile methods require greater communication between testers and developers and collaboration within small teams.
Ad hoc testing and exploratory testing are important methodologies for checking software integrity, because they require less preparation time to implement, while the important bugs can be found quickly. In ad hoc testing, where testing takes place in an improvised, impromptu way, the ability of a test tool to visually record everything that occurs on a system becomes very important in order to document the steps taken to uncover the bug.
Visual testing is gathering recognition in customer acceptance and usability testing, because the test can be used by many individuals involved in the development process. For the customer, it becomes easy to provide detailed bug reports and feedback, and for program users, visual testing can record user actions on screen, as well as their voice and image, to provide a complete picture at the time of software failure for the developers.
Grey-box testing
Grey-box testing (American spelling: gray-box testing) involves having knowledge of internal data structures and algorithms for purposes of designing tests, while executing those tests at the user, or black-box level. The tester is not required to have full access to the software's source code. Manipulating input data and formatting output do not qualify as grey-box, because the input and output are clearly outside of the "black box" that we are calling the system under test. This distinction is particularly important when conducting integration testing between two modules of code written by two different developers, where only the interfaces are exposed for test.
However, tests that require modifying a back-end data repository such as a database or a log file does qualify as grey-box, as the user would not normally be able to change the data repository in normal production operations. Grey-box testing may also include reverse engineering to determine, for instance, boundary values or error messages.
By knowing the underlying concepts of how the software works, the tester makes better-informed testing choices while testing the software from outside. Typically, a grey-box tester will be permitted to set up an isolated testing environment with activities such as seeding a database. The tester can observe the state of the product being tested after performing certain actions such as executing SQL statements against the database and then executing queries to ensure that the expected changes have been reflected. Grey-box testing implements intelligent test scenarios, based on limited information. This will particularly apply to data type handling, exception handling, and so on.
Automated testing
Many programming groups are relying more and more on automated testing, especially groups that use
test-driven development. There are many frameworks to write tests in, and continuous integration software will run tests automatically every time code is checked into a version control system.
While automation cannot reproduce everything that a human can do (and all the ways they think of doing it), it can be very useful for regression testing. However, it does require a well-developed test suite of testing scripts in order to be truly useful.
Automated testing tools
Program testing and fault detection can be aided significantly by testing tools and debuggers.
Testing/debug tools include features such as:
Program monitors, permitting full or partial monitoring of program code including:
Instruction set simulator, permitting complete instruction level monitoring and trace facilities
Hypervisor, permitting complete control of the execution of program code including:-
Program animation, permitting step-by-step execution and conditional breakpoint at source level or in machine code
Code coverage reports
Formatted dump or symbolic debugging, tools allowing inspection of program variables on error or at chosen points
Automated functional GUI (graphical user interface) testing tools are used to repeat system-level tests through the GUI
Benchmarks, allowing run-time performance comparisons to be made
Performance analysis (or profiling tools) that can help to highlight hot spots and resource usage
Some of these features may be incorporated into a single composite tool or an Integrated Development Environment (IDE).
Abstraction of application layers as applied to automated testing
There are generally four recognized levels of tests: unit testing, integration testing, component interface testing, and system testing. Tests are frequently grouped by where they are added in the software development process, or by the level of specificity of the test. The main levels during the development process as defined by the SWEBOK guide are unit-, integration-, and system testing that are distinguished by the test target without implying a specific process model. Other test levels are classified by the testing objective.
There are two different levels of tests from the perspective of customers: low-level testing (LLT) and high-level testing (HLT). LLT is a group of tests for different level components of software application or product. HLT is a group of tests for the whole software application or product.
Unit testing
Unit testing refers to tests that verify the functionality of a specific section of code, usually at the function level. In an object-oriented environment, this is usually at the class level, and the minimal unit tests include the constructors and destructors.
These types of tests are usually written by developers as they work on code (white-box style), to ensure that the specific function is working as expected. One function might have multiple tests, to catch corner cases or other branches in the code. Unit testing alone cannot verify the functionality of a piece of software, but rather is used to ensure that the building blocks of the software work independently from each other.
Unit testing is a software development process that involves synchronized application of a broad spectrum of defect prevention and detection strategies in order to reduce software development risks, time, and costs. It is performed by the software developer or engineer during the construction phase of the software development lifecycle. Rather than replace traditional QA focuses, it augments it. Unit testing aims to eliminate construction errors before code is promoted to QA; this strategy is intended to increase the quality of the resulting software as well as the efficiency of the overall development and QA process.
Depending on the organization's expectations for software development, unit testing might include static code analysis, data-flow analysis, metrics analysis, peer code reviews, code coverage analysis and other software verification practices.
Integration testing
Integration testing is any type of software testing that seeks to verify the interfaces between components against a software design. Software components may be integrated in an iterative way or all together ("big bang"). Normally the former is considered a better practice since it allows interface issues to be located more quickly and fixed.
Integration testing works to expose defects in the interfaces and interaction between integrated components (modules). Progressively larger groups of tested software components corresponding to elements of the architectural design are integrated and tested until the software works as a system.
Component interface testing
The practice of component interface testing can be used to check the handling of data passed between various units, or subsystem components, beyond full integration testing between those units. The data being passed can be considered as "message packets" and the range or data types can be checked, for data generated from one unit, and tested for validity before being passed into another unit. One option for interface testing is to keep a separate log file of data items being passed, often with a timestamp logged to allow analysis of thousands of cases of data passed between units for days or weeks. Tests can include checking the handling of some extreme data values while other interface variables are passed as normal values. Unusual data values in an interface can help explain unexpected performance in the next unit. Component interface testing is a variation of black-box testing, with the focus on the data values beyond just the related actions of a subsystem component.
System testing
System testing tests a completely integrated system to verify that the system meets its requirements. For example, a system test might involve testing a logon interface, then creating and editing an entry, plus sending or printing results, followed by summary processing or deletion (or archiving) of entries, then logoff.
Operational acceptance testing
Operational acceptance is used to conduct operational readiness (pre-release) of a product, service or system as part of a quality management system. OAT is a common type of non-functional software testing, used mainly in software development and software maintenance projects. This type of testing focuses on the operational readiness of the system to be supported, and/or to become part of the production environment. Hence, it is also known as operational readiness testing (ORT) or Operations readiness and assurance (OR&A) testing. Functional testing within OAT is limited to those tests which are required to verify the non-functional aspects of the system.
In addition, the software testing should ensure that the portability of the system, as well as working as expected, does not also damage or partially corrupt its operating environment or cause other processes within that environment to become inoperative.
Compatibility testing
A common cause of software failure (real or perceived) is a lack of its compatibility with other application software, operating systems (or operating system versions, old or new), or target environments that differ greatly from the original (such as a terminal or GUI application intended to be run on the desktop now being required to become a web application, which must render in a web browser). For example, in the case of a lack of backward compatibility, this can occur because the programmers develop and test software only on the latest version of the target environment, which not all users may be running. This results in the unintended consequence that the latest work may not function on earlier versions of the target environment, or on older hardware that earlier versions of the target environment was capable of using. Sometimes such issues can be fixed by proactively abstracting operating system functionality into a separate program module or library.
Smoke and sanity testing
Sanity testing determines whether it is reasonable to proceed with further testing.
Smoke testing consists of minimal attempts to operate the software, designed to determine whether there are any basic problems that will prevent it from working at all. Such tests can be used as build verification test.
Regression testing
Regression testing focuses on finding defects after a major code change has occurred. Specifically, it seeks to uncover software regressions, as degraded or lost features, including old bugs that have come back. Such regressions occur whenever software functionality that was previously working correctly, stops working as intended. Typically, regressions occur as an unintended consequence of program changes, when the newly developed part of the software collides with the previously existing code. Common methods of regression testing include re-running previous sets of test cases and checking whether previously fixed faults have re-emerged. The depth of testing depends on the phase in the release process and the risk of the added features. They can either be complete, for changes added late in the release or deemed to be risky, or be very shallow, consisting of positive tests on each feature, if the changes are early in the release or deemed to be of low risk. Regression testing is typically the largest test effort in commercial software development, due to checking numerous details in prior software features, and even new software can be developed while using some old test cases to test parts of the new design to ensure prior functionality is still supported.
Acceptance testing
Acceptance testing can mean one of two things:
A smoke test is used as an acceptance test prior to introducing a new build to the main testing process, i.e., before integration or regression.
Acceptance testing performed by the customer, often in their lab environment on their own hardware, is known as user acceptance testing (UAT). Acceptance testing may be performed as part of the hand-off process between any two phases of development.
Alpha testing
Alpha testing is simulated or actual operational testing by potential users/customers or an independent test team at the developers' site. Alpha testing is often employed for off-the-shelf software as a form of internal acceptance testing, before the software goes to beta testing.
Beta testing
Beta testing comes after alpha testing and can be considered a form of external user acceptance testing. Versions of the software, known as beta versions, are released to a limited audience outside of the programming team known as beta testers. The software is released to groups of people so that further testing can ensure the product has few faults or bugs. Beta versions can be made available to the open public to increase the feedback field to a maximal number of future users and to deliver value earlier, for an extended or even indefinite period of time (perpetual beta).
Functional vs non-functional testing
Functional testing refers to activities that verify a specific action or function of the code. These are usually found in the code requirements documentation, although some development methodologies work from use cases or user stories. Functional tests tend to answer the question of "can the user do this" or "does this particular feature work."
Non-functional testing refers to aspects of the software that may not be related to a specific function or user action, such as scalability or other performance, behavior under certain constraints, or security. Testing will determine the breaking point, the point at which extremes of scalability or performance leads to unstable execution. Non-functional requirements tend to be those that reflect the quality of the product, particularly in the context of the suitability perspective of its users.
Continuous testing
Continuous testing is the process of executing automated tests as part of the software delivery pipeline to obtain immediate feedback on the business risks associated with a software release candidate. Continuous testing includes the validation of both functional requirements and non-functional requirements; the scope of testing extends from validating bottom-up requirements or user stories to assessing the system requirements associated with overarching business goals.
Destructive testing
Destructive testing attempts to cause the software or a sub-system to fail. It verifies that the software functions properly even when it receives invalid or unexpected inputs, thereby establishing the robustness of input validation and error-management routines. Software fault injection, in the form of fuzzing, is an example of failure testing. Various commercial non-functional testing tools are linked from the software fault injection page; there are also numerous open-source and free software tools available that perform destructive testing.
Software performance testing
Performance testing is generally executed to determine how a system or sub-system performs in terms of responsiveness and stability under a particular workload. It can also serve to investigate, measure, validate or verify other quality attributes of the system, such as scalability, reliability and resource usage.
Load testing is primarily concerned with testing that the system can continue to operate under a specific load, whether that be large quantities of data or a large number of users. This is generally referred to as software scalability. The related load testing activity of when performed as a non-functional activity is often referred to as endurance testing. Volume testing is a way to test software functions even when certain components (for example a file or database) increase radically in size. Stress testing is a way to test reliability under unexpected or rare workloads. Stability testing (often referred to as load or endurance testing) checks to see if the software can continuously function well in or above an acceptable period.
There is little agreement on what the specific goals of performance testing are. The terms load testing, performance testing, scalability testing, and volume testing, are often used interchangeably.
Real-time software systems have strict timing constraints. To test if timing constraints are met, real-time testing is used.
Usability testing
Usability testing is to check if the user interface is easy to use and understand. It is concerned mainly with the use of the application.
Accessibility testing
Accessibility testing may include compliance with standards such as:
Americans with Disabilities Act of 1990
Section 508 Amendment to the Rehabilitation Act of 1973
Web Accessibility Initiative (WAI) of the World Wide Web Consortium (W3C)
Security testing
Security testing is essential for software that processes confidential data to prevent system intrusion by hackers.
The International Organization for Standardization (ISO) defines this as a "type of testing conducted to evaluate the degree to which a test item, and associated data and information, are protected so that unauthorised persons or systems cannot use, read or modify them, and authorized persons or systems are not denied access to them."
Internationalization and localization testing
The general ability of software to be internationalized and localized can be automatically tested without actual translation, by using pseudolocalization. It will verify that the application still works, even after it has been translated into a new language or adapted for a new culture (such as different currencies or time zones).
Actual translation to human languages must be tested, too. Possible localization failures include:
Software is often localized by translating a list of strings out of context, and the translator may choose the wrong translation for an ambiguous source string.
Technical terminology may become inconsistent if the project is translated by several people without proper coordination or if the translator is imprudent.
Literal word-for-word translations may sound inappropriate, artificial or too technical in the target language.
Untranslated messages in the original language may be left hard coded in the source code.
Some messages may be created automatically at run time and the resulting string may be ungrammatical, functionally incorrect, misleading or confusing.
Software may use a keyboard shortcut which has no function on the source language's keyboard layout, but is used for typing characters in the layout of the target language.
Software may lack support for the character encoding of the target language.
Fonts and font sizes which are appropriate in the source language may be inappropriate in the target language; for example, CJK characters may become unreadable if the font is too small.
A string in the target language may be longer than the software can handle. This may make the string partly invisible to the user or cause the software to crash or malfunction.
Software may lack proper support for reading or writing bi-directional text.
Software may display images with text that was not localized.
Localized operating systems may have differently named system configuration files and environment variables and different formats for date and currency.
Development testing
"Development testing" is a software development process that involves synchronized application of a broad spectrum of defect prevention and detection strategies in order to reduce software development risks, time, and costs. It is performed by the software developer or engineer during the construction phase of the software development lifecycle. Rather than replace traditional QA focuses, it augments it. Development Testing aims to eliminate construction errors before code is promoted to QA; this strategy is intended to increase the quality of the resulting software as well as the efficiency of the overall development and QA process.
Depending on the organization's expectations for software development, Development Testing might include static code analysis, data flow analysis, metrics analysis, peer code reviews, unit testing, code coverage analysis, traceability, and other software verification practices.
A/B testing
A/B testing is basically a comparison of two outputs, generally when only one variable has changed: run a test, change one thing, run the test again, compare the results. This is more useful with more small-scale situations, but very useful in fine-tuning any program. With more complex projects, multivariant testing can be done.
Concurrent testing
In concurrent testing, the focus is on the performance while continuously running with normal input and under normal operational conditions, as opposed to stress testing, or fuzz testing. Memory leaks, as well as basic faults are easier to find with this method.
Conformance testing or type testing
In software testing, conformance testing verifies that a product performs according to its specified standards. Compilers, for instance, are extensively tested to determine whether they meet the recognized standard for that language.
References
External links
Computing-related lists
Tactics | Software testing tactics | [
"Technology",
"Engineering"
] | 5,221 | [
"Computing-related lists",
"Software testing",
"Software engineering"
] |
53,489,954 | https://en.wikipedia.org/wiki/Fortschritt%20ZT%20300 | ZT 300 is a series of 20 kN agricultural tractors, produced from 1 September 1967 to 1984 by the VEB Traktorenwerk Schönebeck. It succeeded the RS14 Famulus series, and unlike the Famulus, the ZT 300 series was sold under the brand name Fortschritt ("Progress"). ZT 300 refers both to the initial ZT 300 model, and the ZT 300 series. In total, 72,382 units of the ZT 300 series were made. The model with the highest production figure was the ZT 303, which was introduced in 1972. It features an automatic all-wheel-drive system; in the early 1980s, it cost 81,000 Mark. Starting in 1983, the ZT 300 series was succeeded by the ZT 320.
Chronology
In total, the ZT 300 series consisted of 6 series production models and one prototype:
ZT 300: The base model with rear-wheel drive, meant for agricultural use
ZT 303: All-wheel model, it shares its front axle with the IFA W50 LA
ZT 304: A road tractor, no hydraulics, no PTO, no work lights, no powershift gearbox
ZT 305: Like the ZT 303, with additional twin tyres and enhanced dual-circuit brakes
ZT 300 GB: Based on the ZT 300, has rubber tracks instead of tyres
ZT 403: An engine upgrade for the ZT 303, the four-cylinder engine was replaced with a six-cylinder engine (type 6 VD 14,5/12-1 SRW) producing 110 kW
ZT 307: An engine upgrade for the ZT 305, the four-cylinder engine was replaced with a six-cylinder engine (type 6 VD 14,5/12-1 SRW) producing 110 kW. This model remained a prototype.
Some tractors were converted into road-rail-vehicles. They were mainly used for shunting in smaller East German plants.
Technical description
The ZT 300 series tractors design is based on a combination of the frameless block construction for the rear part and a half frame for the front. This makes the rear axle an unsprung, rigid beam axle, whereas the front beam axle has a pivot point and allows wheel travel. The ZT 300 has a three-point-linkage with a lifting force of 17.65 kN and a PTO as well as a hydraulic system. Starting in 1974, an optimised hydraulic system was used, that automatically increased the weight on the rear axle by slightly lifting the farm implement attached to the three-point linkage, if required. This resulted in better traction and therefore greater drawbar pull force.
All ZT 300 tractors have a manual three-speed semi powerspeed gearbox with three forward and two reverse ranges, this results in a total of nine forward and six reverse gears. It allows speeds between 3.1 and ca. 30 km/h. A pneumatic two stage clutch of the type DK 80 is used to transmit the torque to the gearbox. The first clutch stage connects the gearbox, the second stage connects the PTO shaft(s), hydraulic system and the load stage of the gearbox. The load stage increases the torque transmitted to the wheels. It can be switched without having to stop the tractor by moving the load stage lever and pressing the clutch pedal. The rear axle also has a differential lock.
The engine is the 4 VD 14,5/12-1 SRW, a straight four-cylinder, direct-injected, diesel engine with a displacement of 6560 cc. Initially, it was detuned to produce 66 kW at 1500 rpm, but in 1973, the power output was increased to 68 kW, and in 1978, to 74 kW at 1800 rpm. The maximum torque is 422 Nm at 1350 rpm. The specific fuel consumption is rated 238 g/kWh at 1350 rpm.
The initial ZT 300 models have a rack-and-pinion steering, whereas later models have a fully hydraulic steering system. Only the rear wheels have brakes. All tractors may pull trailers with a maximum payload of 24.000 kg, if the trailer has a pneumatic brake system.
All wheel drive system
The all wheel drive system enables itself automatically using a roller-type overrunning clutch if the wheel slip is greater than 7–8 percent. The front axle is same as in the IFA W50 LA, this results in less ground clearance compared to the rear wheel drive ZT 300 tractors. Like the rear axle, the AWD front axle has a lockable differential. The ZT 305 also has brakes for the front wheels, bigger tyres and rear twin tyres; it was developed for slopes with gradients of up to 45 percent.
Forward and reverse speeds
Paint colours
The ZT 300 series tractors were made with four different paint colours:
Vermillion/Grey-white/Squirrel-grey
Azure/Grey-white/Squirrel-grey
Reseda/Grey-white/Squirrel-grey
TGL 21196
References
Bibliography
Achim Bischof: Traktoren in der DDR. Podszun, Brilon 2004, .
Klaus Tietgens: Fortschritt ZT 300. Typengeschichte und Technik. GeraMond, München 2014, .
Jan Welkerling: FORTSCHRITT in allen Ähren. DDR-Landmaschinen im Einsatz. 2005.
External links
Tractors
IFA vehicles
Vehicles introduced in 1967 | Fortschritt ZT 300 | [
"Engineering"
] | 1,125 | [
"Engineering vehicles",
"Tractors"
] |
53,490,631 | https://en.wikipedia.org/wiki/OPTOS%20formalism | OPTOS (optical properties of textured optical sheets) is a simulation formalism for determining optical properties of sheets with plane-parallel structured interfaces. The method is versatile as interface structures of different optical regimes, e.g. geometrical and wave optics, can be included. It is very efficient due to the re-usability of the calculated light redistribution properties of the individual interfaces. It has so far been mainly used to model optical properties of solar cells and solar modules but it is also applicable for example to LEDs or OLEDs with light extraction structures.
History
The development of the OPTOS formalism started in 2015 at the Fraunhofer Institute for Solar Energy Systems ISE in Freiburg, Germany. The mathematical formulation has been described in detail in several open access publications.
A basic version of the code including documentation with function references has been available since the end of 2015 at the homepage of Fraunhofer ISE. Continuous updates and a list of OPTOS related publications can be found on ResearchGate.
OPTOS simulation procedure
One key aspect of OPTOS simulations is the division of the modeled system into interface and propagation regions. The light redistribution properties are calculated with the most appropriate method for each interface individually and depending on the relevant structure dimension. Large scale structures can for example be modeled via ray tracing while for interfaces with structure dimensions in the range of the wavelength wave optical approaches like RCWA, FDTD or FEM can be used.
System description
The discretization of the complete angular space into a fixed number of angle channels, as second key aspect of the OPTOS formalism, allows representing the angular power distribution within the system by a vector v which consists of one entry for each angle channel. The value of the entry is the power fraction of the corresponding angle channel with respect to the total incident power.
Interface interaction
The light redistribution properties of an interface are represented by the so-called reflection and transmission matrices, R and T. They store for each of the angle channels the redistribution information into other angle channels for light incident onto a certain interface with a certain wavelength. There are in total four different redistribution matrices for each interface, characterized by the incidence direction as well as reflection or transmission redistribution.
Propagation through the sheet
The incoherent propagation of light through the sheet can also be represented by a matrix. If no light redistribution takes occurs on the path, the propagation matrix D is a diagonal matrix. The single entries consist of the Lambert-Beer absorption factor, including cosine of the polar angle and the absorption coefficient of the respective material.
Calculation of optical properties
Using the pre-calculated matrices described above, optical properties like reflectance, transmittance or absorptance within the sheet can be calculated via matrix multiplications [2–4] and can be performed within seconds or minutes using a standard personal computer. Also a depth-dependent absorption profile can be calculated. This is of special importance for the subsequent electrical simulation of structured silicon solar cells.
OPTOS simulation characteristics
Strengths
Versatility – Optical systems with interface structures operating in different optical regimes can be accurately simulated. The redistribution properties of each interface are modeled individually with the most suitable method.
Efficiency - The re-usability of the redistribution allow for the very fast simulation of different structure combinations, sheet thickness variations and the optical analysis with respect to different angles of incidence.
Linear polarization can be taken into account by exchanging each entry of the power distribution vector with two entries, one for each polarization direction. Each matrix entry has to be exchanged with a two by two matrix taking also the redistribution between different polarization directions into account.
Limitations
OPTOS couples redistribution properties of different interfaces. If there is no accurate modeling technique to calculate redistribution matrices, such interfaces cannot be included in OPTOS.
OPTOS models the propagation through the sheet incoherently. If the sheet thickness becomes very low and interference effects play a significant role, this needs to be handled coherently and not as “thick” sheet. However, as coherently modeled sub-system, it can be included in OPTOS as effective interface.
Circular or elliptical polarization effects are not taken into account as all phase information is neglected during the propagation.
Application Examples
The main application of OPTOS has so far been the simulation of:
Solar cells with different front and rear side structures such as random pyramids, the isotexture, the honeycomb texture or diffractive gratings.
The layer stack of solar panels, including the effect of the encapsulation onto the optical solar cell properties as well as the investigation of different angles of incidence.
Complex optical interactions in photovoltaic systems with nanowire solar cells.
The OPTOS formalism has been incorporated into the open-source software RayFlare. This software also allows the user to calculate appropriate redistribution matrices using various methods including the transfer-matrix method, ray tracing, and rigorous coupled-wave analysis.
Alternative fields of application could be:
LEDs or OLEDs with light extraction structures
Display technology, for example brightness enhancement films
References
External links
OPTOS page at Fraunhoer ISE website (includes documentation and download of basic version)
OPTOS project on ResearchGate (with continuous updates and a list of OPTOS related publications)
Physical optics
Computational electromagnetics | OPTOS formalism | [
"Physics"
] | 1,057 | [
"Computational electromagnetics",
"Computational physics"
] |
53,491,295 | https://en.wikipedia.org/wiki/Corticocortical%20coherence | Corticocortical coherence refers to the synchrony in the neural activity of different cortical brain areas. The neural activities are picked up by electrophysiological recordings from the brain (e.g. EEG, MEG, ECoG, etc.). It is a method to study the brain's neural communication and function at rest or during functional tasks.
History and basics
Initial applications of spectral analysis for finding the relationship between the EEG recordings from different regions of scalp dates back to 1960's. Corticocortical coherence has since been extensively studied using EEG and MEG recording for potential diagnostic applications and beyond.
The exact origins of corticocortical coherence are under active investigation. While the consensus suggests that the functional neural communication between distinct brain sources leads to synchronous activity in those regions (possibly connected by neural tracts, in either direct or indirect way), an alternative explanation emphasises on single focal oscillations that occur at single brain sources that eventually appear connected or synchronous in different scalp or brain source regions.
Corticocortical coherence has been of special interest in delta, theta, alpha, beta and gamma frequency bands (commonly used for EEG studies).
Methods, mathematics and statistics
Cortico-cortical coherence is commonly studied using bipolar channels of EEG recordings, as well as unipolar channels of EEG or MEG signals; however, unipolar channels are usually used to estimate the brain sources and their connectivity, using electrical source imaging and connectivity analysis.
A classic and commonly used approach to assess the synchrony between neural signals is to use Coherence.
Statistical significance of coherence is found as function of number of data segments with assumption of the signals' normal distribution. Alternatively non-parametric techniques such as bootstrapping can be used.
See also
Intermuscular coherence
Corticomuscular coherence
External links
Neurspec Toolbox for MATLAB
References
Neuroscience | Corticocortical coherence | [
"Biology"
] | 416 | [
"Neuroscience"
] |
53,492,317 | https://en.wikipedia.org/wiki/Water%20recycling%20shower | Water recycling showers (also known as recycle showers, circulation showers or re-circulation showers) are showers that use a basin and a pump to re-use the water during a shower session. The technology is used to reduce the use of drinking water and primary energy consumption for water heating. By lowering the (household) hot water demand, water recycling showers also allow for smaller heating appliances, like boilers, solar water heating systems and other HVAC solutions.
History
The first recycling shower, operated by a hand pump, was patented in England in 1767 by the stove maker William Feetham. This recycling shower used the pump to push the water into a basin above the user's head. To receive the water, the user pulled a chain to release the water from the basin. Like this, the invention would recycle the same dirty water during the entire session. It also gradually lost temperature.
It was not until 200 years later, in 1979, that Billy G. Bloys invented a motorized version of the same concept, discarding the hand pump. Using no filtration or a means of re-heating the water, the contraption likened the original invention by Feetham but did not improve on it beyond the electronic pump and some fixtures. It was never commercialized. In 1988, Francis R. Keeler patented a similar but smaller and more mobile version of the recycling shower for usage in motor homes, boats and airplanes.
In 2011, Nick Christy of Australia won the Postcode Lottery Green Challenge, an annual competition for sustainable ideas for his version of the water recycling shower. The shower aimed to collect, filter, pasteurize and then dilute the water with fresh tap water to cool it again to the set temperature. Citing cultural problems and lack of traction in his native Australia, Christy aimed for the UK market. They are yet to collect certification standards.
In 2013, the Swedish company Orbital Systems introduces their first shower, the launching company being a spinoff from a NASA internship. It comprises a closed-loop system where the water is purified using a replaceable filter. These filter out particulate matter and microbes from drain water before sending the water back through the head. After the capsules have been depleted, they have to be replaced at cost. Orbital Systems has had several high-profile investors, including Skype and Kazaa co-founder Niklas Zennström and Karl-Johan Persson, CEO of the fashion company H&M.
In 2015, the Dutch company Hamwells introduced the e-Shower at the TechCrunch Disrupt conference in London. Citing hygiene issues in earlier solutions, Hamwells opted for a solution with a semi-closed loop where the water is used several times instead of the entire session. External hot water is used to maintain temperature, with incoming hot water replacing the used water within the loop. In addition to replacement, water within the loop is filtered and purified with UV light. For users unable or unwilling to use the recycling mode, the e-Shower offers a classic shower where all the water is drained. Being a computer, the e-Shower is able to self-clean, regulate shower times between users and offer the user music streaming and remote control through mobile apps.
Benefits
Water recycling showers have been explored by people who wish to conserve water and the energy needed to heat the water, for both environmental and economic reasons.
Energy savings
According to the U.S. Department of Energy, water heating is typically the second-largest energy expense in homes (after space heating). Mostly destined for the shower, it accounts for roughly 17% of total household energy consumption. Energy efficiency was the main driver behind the federal regulation, mandating the top flow of a shower head to be restricted to 2.5 gallons per minute. Manufacturers of recycling showers typically claim a 70% to 90% reduction in shower energy consumption.
Water savings
Nearly 1.2 trillion gallons of water is used in the United States annually just for showering. This is enough to supply the water needs of New York and New Jersey for a year. Manufacturers of recycling showers typically claim an 80% to 90% reduction in shower water consumption.
Also, before the shower reaches the set temperature, users leave the tap running. Typically 20 percent of every shower session is essentially lost this way.
See also
Water heat recycling
References
Water conservation tools
Bathing
Hygiene
Plumbing
Recycling | Water recycling shower | [
"Engineering"
] | 884 | [
"Construction",
"Plumbing"
] |
53,493,192 | https://en.wikipedia.org/wiki/GLAD-PCR%20assay | Glal hydrolysis and Ligation Adapter Dependent PCR assay (GLAD-PCR assay) is the novel method to determine R(5mC)GY sites produced in the course of de novo DNA methylation with DNMTЗA and DNMTЗB DNA methyltransferases. GLAD-PCR assay do not require bisulfite treatment of the DNA.
Method was specially designed to determine methylation of RCGY site of interest in human and mammalian genomes in excess of corresponding unmethylated sites. This is a typical situation for DNA preparations from clinical samples of blood and tissues.
GLAD-PCR assay is based on the new type of enzymes - site-specific methyl-directed DNA-endonucleases (MD DNA endonucleases). These enzymes are very similar to restriction enzymes in biochemical properties and cleave DNA completely, but act in opposite way: they cleave only methylated DNA and do not cleave unmethylated DNA at all. Mammalian DNA-methyltransferases DNMT1, DNMT3a and DNMT3b catalyze a reaction of DNA methylation.
DNMT1 maintains DNA methylation pattern in vivo modifying a new strand after replication.
DNMT3a and DNMT3b are responsible for DNA methylation de novo including abnormal hypermethylation in cancer cells.
It is well known that hypermethylation of CpG-islands in regulatory regions of promoter and/or first exon in a variety of genes often occurs at early stages of sporadic carcinogenesis. This leads to downregulation of the genes expression in tumor cells, whereas in a healthy tissue the corresponding genes remain to be active. Thus, the detection of such epigenetic biomarkers is one of the most promising diagnostic and prognostic tools
Study of DNMT3a and DNMT3b substrate specificity has shown that both enzymes predominantly recognize RCGY site and modify internal CG-dinucleotide to form 5’-R(5mC)GY-3’/3’-YG(5mC) R-5’ sequence. One of new enzymes GlaI recognizes and cleaves site R(5mC)GY. Due to this unique substrate specificity, GlaI is a convenient tool for identification of de novo methylated sites in the human and mammalian DNA.GLAD-PCR assay includes 3 simple steps:
GlaI hydrolysis of the studied DNA. At this step only R(5mC)GY sites are hydrolyzed. Unmethylated RCGY sites remain uncut.
The universal adapter ligation. As an adapter an oligonucleotide duplex 5’-CCTGCTCTTTCATCG-3’/3’-pGGACGAGAAAGTAGCp-5’ is used, where “p” means phosphate.
Subsequent real-time PCR with Taqman probe. Genome primer and TaqMan probe are designed for DNA region of interest, another hybrid primer consist of two parts: one part is complementary to the universal adapter and another one - to the DNA at the point of GlaI hydrolysis.
Assay is performed in one tube, takes about 2–3 hours and determines even several copies of DNA with R(5mC)GY site of interest.
References
Epigenetics
Methylation
Molecular biology techniques | GLAD-PCR assay | [
"Chemistry",
"Biology"
] | 718 | [
"Molecular biology techniques",
"Methylation",
"Molecular biology"
] |
53,493,533 | https://en.wikipedia.org/wiki/Proxicromil | Proxicromil is a detergent-like, lipophilic oral medication developed in the late 1970s that was not admitted on the market because of its possible carcinogenic effects. It suppresses allergic reactions by binding to FcεRI receptor in mast cells, thereby inhibiting production of histamines. It is absorbed through the gastrointestinal tract, and has been proven hepatotoxic for dogs as a result of its accumulation in biliary canaliculi.
History
Proxicromil was developed in the late 1970s as an oral analogue and a successor of anti-allergy drug Intal, whose patent protection period was to expire in 1982. Disodium cromoglycate in the form of an inhaler licensed as Intal (derived from ‘interfere with allergy’) had become the Fisons company's leading product, generating immense income and stimulating further research; thus several attempts at developing a congener were undertaken. Nevertheless, because of its possible carcinogenic properties, Fisons decided to withdraw the drug in 1981, just before it was to be marketed.
Structure and reactivity
Proxicromil has a strongly acidic chromone skeleton. The 5-hydroxy group increases the activity and, along with the 10-alkyl group, causes an increase in lipophilicity of the compound. The relatively high lipophilicity of the molecule allows it to be absorbed from the gastrointestinal tract. It is postulated that the absorption may take place via ion-pair formation. Due to these properties proxicromil operates efficiently as a mast cell stabilizer, preventing the release of histamine. This causes the compound to have anti-allergic properties.
Synthesis
The condensation of 6-acetyl-7-hydroxy-1,2,3,4-tetrahydronaphthalene (I) with allyl bromide (A) using of K2CO3 in DMF gives 6-acetyl-7-allyloxy-1,2,3,4-tetrahydronaphthalene (II), which is isomerized to 5-allyl-7-acetyl-6-hydroxy-1,2,3,4-tetrahydronaphthalene (III) by warming at 200 °C. Reduction of (III) with H2 over Pd/C in ethanol results in 5-propyl-7-acetyl-6-hydroxy-1,2,3,4-tetrahydronaphthalene (IV), which is now cyclized using diethyl oxalate (B) using sodium ethoxide in refluxing ethanol to give ethyl 10-propyl-4-oxo-6,7,8,9-tetrahydro-4H-naphtho[2,3-b]pyran-2-carboxylate (V).
The nitration of (V) with nitric acid in sulfuric acid gives ethyl 10-propyl-4-oxo-5-nitro-6,7,8,9-tetrahydro-4H-naphtho[2,3-b]pyran-2-carboxylate (VII), which is hydrogenated with H2 over Pd/C in ethanol-acetic acid to afford the corresponding amino derivative (VIII). At the end, this substance is diazotated with NaNO2 and H2SO4 and afterwards treated with 50% H2SO4 at 120 °C.
Mechanism of action
Mast cells are a type of white blood cells that function in the immune and neuro-immune system. Allergic reactions or responses to inflammation or invading microorganisms are coordinated by these cells in a process called degranulation. Antimicrobial cytotoxic and inflammatory mediators, such as histamine, proteoglycans, serotonin and serine proteases, are released from cytoplasmic granules in the mast cells once their high-affinity receptors FcεRI detect IgE antibodies and bind their Fc region. The released histamines cause irritations to the organism such as sneezing and an itchy sensation in the nose.
Proxicromil acts as an inhibitor of this process, competing with IgE antibodies for binding with the FcεRI receptors, thereby reducing the irritation caused by histamines. The substance was found to reduce allergic reactions and the severity of clinical diseases when administered just before the onset.
Furthermore, the antihistamine blocks the elicitation of adoptively transferred EAE, an allergic brain inflammation reaction, and it shows a reducing effect on the severity of skin irritation.
Metabolism
The pathway of metabolism, by most tested species, is by hydroxylation of the alicyclic ring to yield monohydroxylated metabolites with trace amounts of dihydroxylated product.
This pathway occurs in rats, hamsters, rabbits, squirrel monkeys, cynomolgus monkeys, baboons and humans, where the metabolites are found in urine and faeces.
For dogs a different elimination occurs, which is essentially as the unchanged drug. The reason for this difference in species, results from the dog having a higher dependence on biliary excretion of the unchanged drug for clearance. The value of the plasma clearance for dogs (0.2 ml min-1 kg-1), is 20 fold lower than the value for rats (4.1 ml min-1 kg-1), a species which is capable of metabolism. This difference leads to the different clearance route. Which becomes saturated after administration of a toxic dose of the drug.
If the metabolism of proxicromil in a rat is inhibited with SKF-525A, the plasma clearance of proxicromil is lowered (0.6 ml min-1 kg-1), which increases the amount of unchanged drug cleared by biliary excretion.
After giving nursing rat mothers proxicromil, the drug and its metabolites gets also excrete in the milk of these rats. At a maternal dose level of 20 mg/kg, an amount 1-2% was present in the milk. From which 63% was proxicromil and 37% the hydroxylated metabolites.
Efficacy, toxicity and side effects
Proxicromil is tested through a variety of independent studies for its beneficial effect as an anti-allergen, its efficacy against migraine, asthma and tumor enhancement. It shows no effect as a prophylactic against migraine. The reported side effects during this study related mainly to transient gastrointestinal troubles and were generally of a mild nature.
For asthma and exercise-induced bronchospasm, Proxicromil was found to be mildly effective. But the investigation was discontinued when malignancies occurred in long-term animal studies.
In preventing in vitro antigen-induced pulmonary anaphylaxis, Proxicromil was found to be twenty times less potent than Cl-922, another anti-allergy compound. The same result were found in an animal model with rats.
Treatment with Proxicromil reverses the tumor enhancement in immunosuppressed animals.
Proxicromil is a mast-cell stabilizer that prevents degranulation and release of mediators such as histamine from mast cells. In normal animals, the drug has no effect.
Proxicromil is found to be hepatotoxic in dogs but not in rats, which is a result from the different metabolisms. This comes through the route of excretion which Proxicromil undergoes and which leads to a high concentrations at the biliary canaliculus and thus its accumulation and a consequent increase in hepatic exposure.
Animal studies revealed possible carcinogenic properties.
References
Antihistamines
Abandoned drugs
Heterocyclic compounds with 3 rings
Oxygen heterocycles | Proxicromil | [
"Chemistry"
] | 1,677 | [
"Drug safety",
"Abandoned drugs"
] |
53,494,139 | https://en.wikipedia.org/wiki/Shirley%20E.%20Schwartz | Shirley Ellen Schwartz or Ellen Shirley Schwartz (August 26, 1935 – May 8, 2016) was an American chemist and research scientist at General Motors, specializing in the study and development of industrial lubricants and automobile oil change indicator systems. She was inducted into the Michigan Women's Hall of Fame in 1996 for her accomplishments in the field of chemistry.
Early life and education
Born Ellen Shirley Eckwall in Detroit, Schwartz grew up in the Detroit suburb of Pleasant Ridge, and graduated from Lincoln High School in Ferndale. She earned three academic degrees in chemistry. She attended the University of Michigan where she received her Bachelor of Science degree in chemistry in 1957. Schwartz then enrolled at Wayne State University and earned her master's degree 1962 and her doctorate in 1970.
Career
After teaching at Oakland Community College and the Detroit Institute of Technology, Schwartz began working at BASF Corporation in Wyandotte, Michigan, where she developed an industrial lubricant that, by virtue of being primarily water, reduced the amount of oil and consequently pollution. She then spent over 18 years working at General Motors, where she was senior research scientist, working in Research and Development Operations at the General Motors Technical Center in Warren, Michigan. During her career she came to hold more than 20 patents, and authored 173 technical papers. From 1989 to 2003 she wrote a regular column titled Love Letters to Lubrication Engineers in the journal of the Society of Tribologists and Lubrication Engineers, and was remembered in a 2016 memorial in that journal as "the mother of the oil life monitor found in most GM cars, which is responsible for not having to change oil nearly as often as we did previously, or conversely, not ruining your engine if you don't change it often enough."
When presenting her with an achievement award in 1999, the Society of Women Engineers summarized Dr. Schwartz's career thusly:
"Dr. Schwartz has examined engine oil degradation; wear, corrosion, and elastomer durability in engines; the effects of methanol and ethanol fuel on engines; and lubricants for air conditioners that use alternative refrigerants (other than Freon R12). Her work in these areas have been targeted towards:
obtaining the maximum useful life of engine oil
finding acceptable ways to use alternative energy sources
developing refrigerant systems that will not hurt the earth's ozone layer"
Awards and honors
Schwartz was named a fellow of the Society of Automotive Engineers in 1999 and was elected to the National Academy of Engineering in 2000 "for contributions to lubrication engineering and for enriching the technical community through free-lance writing." She additionally received many industry awards:
General Motors Kettering Award (1988): Awarded for computer-based method that assesses engine oil degradation as a function of oil temperature and displays the remaining life of the oil for the vehicle
General Motors McCuen Award (1993)
Gold Award from the Engineering Society of Detroit (1989)
Wilbur Deutsch Memorial Award from the Society of Tribologists and Lubrication Engineers (1987)
Colwell Award (1992) from the Society of Automotive Engineers
Distinguished Speaker Award (1995) from the Society of Automotive Engineers
Personal life
Schwartz married her husband, Ron Schwartz, in 1957.
References
1935 births
2016 deaths
20th-century American chemists
American materials scientists
Detroit Institute of Technology faculty
General Motors people
Members of the United States National Academy of Engineering
Tribologists
Women materials scientists and engineers
University of Michigan College of Literature, Science, and the Arts alumni
Wayne State University alumni
People from Pleasant Ridge, Michigan
People from Warren, Michigan
Chemists from Michigan
Scientists from Detroit
Deaths from Alzheimer's disease in the United States
Deaths from dementia in Michigan | Shirley E. Schwartz | [
"Materials_science",
"Technology"
] | 751 | [
"Tribology",
"Tribologists",
"Materials scientists and engineers",
"Women materials scientists and engineers",
"Women in science and technology"
] |
53,494,172 | https://en.wikipedia.org/wiki/Price%20of%20anarchy%20in%20auctions | The Price of Anarchy (PoA) is a concept in game theory and mechanism design that measures how the social welfare of a system degrades due to selfish behavior of its agents. It has been studied extensively in various contexts, particularly in auctions.
In an auction, there are one or more items and one or more agents with different valuations for the items.
The items have to be divided among the agents. It is desired that the social welfare - the sum of values of all agents - be as high as possible.
One approach to maximizing the social welfare is designing a truthful mechanism. In such a mechanism, each agent is incentivized to report his true valuations to the items. Then, the auctioneer can calculate and implement an allocation that maximizes the sum of values. An example to such a mechanism is the VCG auction.
In practice, however, it is not always feasible to use truthful mechanisms. The VCG mechanism, for example, might be too complicated for the participants to understand, might take too long for the auctioneer to compute, and might have other disadvantages.
In practice, non-truthful mechanisms are often used, and it is interesting to calculate how much social welfare is lost by this non-truthfulness.
It is often assumed that, in a non-truthful auction, the participants play an equilibrium strategy, such as a Nash equilibrium. The price-of-anarchy of the auction is defined as the ratio between the optimal social welfare and the social welfare in the worst equilibrium:
A related notion is the Price of Stability (PoS) which measures the ratio between the optimal social welfare and the social welfare in the best equilibrium:
Obviously .
When there is complete information (each agent knows the valuations of all other agents), the common equilibrium type is Nash equilibrium - either pure or mixed. When there is incomplete information, the common equilibrium type is Bayes-Nash equilibrium. In the latter case, it is common to speak of the Bayesian price of anarchy, or BPoA.
Single-item auctions
In a first-price auction of a single item, a Nash equilibrium is always efficient, so the PoA and PoS are 1.
In a second-price auction, there is a Nash equilibrium in which the agents report truthfully; it is efficient, so the PoS is 1. However, the PoA is unbounded. For example, suppose there are two players: Alice values the item as a and Bob as b, with a>b.
There exists a "good" Nash equilibrium in which Alice bids a and Bob bids b; Alice receives the item and pays b. The social welfare is a, which is optimal.
However, there also exists a "bad" Nash equilibrium in which Alice bids 0 and Bob bids e.g. a+1; Bob receives the item and pays nothing. This is an equilibrium since Alice does not want to overbid Bob. The social welfare is b. Hence, the PoA is a/b, which is unbounded.
This result seems overly pessimistic:
First, in a second-price auction, it is a weakly-dominant strategy for each agent to report his true valuation. If we assume that agents follow their dominant strategies, then the PoA is 1.
Moreover, it is a dominated strategy for each agent to report any value above his true valuation.
Therefore, it is common to analyze the PoA under a no overbidding assumption - no agent bids above his true valuation. Under this assumption, the PoA of a single-item auction is 1.
Parallel auctions
In a parallel (simultaneous) auction, items are sold at the same time to the same group of participants. In contrast to a combinatorial auction - in which the agents can bid on bundles of items, here the agents can only bid on individual items independently of the others. I.e, a strategy of an agent is a vector of bids, one bid per item. The PoA depends on the type of valuations of the buyers, and on the type of auction used for each individual item.
Case 1: submodular buyers, second-price auctions, complete information:
There exists a pure Nash equilibrium with optimal social welfare. Hence, the PoS is 1.
It is possible to calculate in polynomial time a pure Nash equilibrium with social welfare at least half the optimal. Hence, the price of "polynomial-time stability" is at most 2.
The PoA is unbounded - as already shown by the single-item example above. However, under a strong-no-overbidding assumption (the sum of bids of any buyer to any bundle is at most the value of that bundle to the buyer), the PoA is at most 2. The latter result also holds when the buyers' valuations are fractionally subadditive.
Case 2: fractionally subadditive buyers, 2nd-price auction, incomplete information. Assuming strong-no-overbidding, any (mixed) Bayes-Nash equilibrium attains in expectation at least 1/2 the optimal welfare; hence the BPoA is at most 2. This result does not depend on the common prior of the agents.
Case 3: subadditive buyers, 2nd-price auctions. Under a strong-no-overbidding assumption:
With complete information, the welfare of every pure Nash equilibrium is at least 1/2 the optimum, so the PoA is at most 2.
With incomplete information, there exist Bayes-Nash equilibria with welfare less than 1/2 the optimum, so the BPoA is more than 2.
The BPoA is at most , where is the number of items. This guarantee is also valid to coarse correlated equilibrium - and hence to the special cases of mixed Nash equilibrium and correlated equilibrium.
Both of the above upper bounds on the PoA degrade gracefully when the subadditivity and no-overbidding assumptions are relaxed. E.g: if we assume that each player overbids by at most some constant factor, then the PoA grows by at most a constant factor.
Case 4: General (monotone) buyers, first-price auctions, complete information:
The set of pure Nash equilibria of the game are exactly the Walrasian equilibria (price equilibria) of the market.
Since such equilibria are socially-optimal (by the first welfare theorem), the PoA of pure Nash equilibria is 1. Unfortunately, such equilibria might not exist.
A mixed Nash equilibrium always exists (when choosing the right tie-breaking rule). However, it is not necessarily socially-optimal. The PoA might be as high as , and even the PoS might be as high as .
This result also extends to 2nd-price auctions, even with a weak-no-overbidding assumption.
The PoA is at most .
When all valuations are subadditive, the PoA is at most .
When all valuations are -fractionally subadditive, the PoA is at most (in particular, for XOS buyers, the PoA is at most 2).
The latter three bounds hold also for coarse-correlated equilibria; they do NOT require a "no overbidding" assumption.
Case 5: General buyers, 2nd-price auctions, complete information. With general valuations (that may have complementarities), the strong-no-overbidding assumption is too strong, since it prevents buyers from bidding high values on bundles of complementary items. For example, if a buyer's valuation is $100 for a pair of shoes but $1 for each individual shoe, then the strong-no-overbidding assumption prevents him from bidding more than $1 on each shoe, so that he has little chances of winning the pair. Therefore, it is replaced with a weak-no-overbidding assumption, which means that the no-overbidding condition holds only for the bundle that the agent finally wins (i.e, the sum of bids of the buyer to his allocated bundle is at most his value for this specific bundle). Under this weak-no-overbidding assumption:
The set of pure Nash equilibria of the game are exactly the conditional price-equilibria of the market.
Since such equilibria are half-socially-optimal (attain at least half the maximum social welfare), the PoA of pure Nash equilibria is at most 2. Unfortunately, such equilibria might not exist.
Case 6: General buyers, 1st-price auctions, incomplete information. For any common prior:
The BPoA is at most .
When all valuations are -fractionally subadditive, the BPoA is at most (in particular, for XOS buyers, the BPoA is at most 2, and for subadditive buyers, it is ).
Case 7: Subadditive buyers, incomplete information:
When the items are sold in first-price auctions, the BPoA is at most 2.
When the items are sold in second-price auctions, the BPoA is at most 4. This is true both under the strong-no-overbidding assumption (the sum of bids of any buyer to any bundle is at most the value of that bundle to the buyer), and under the weak-no-overbidding assumption (the expected sum of the winning bids of any buyer is at most the expected winning value of that buyer).
Sequential auctions
In a sequential auction, items are sold in consecutive auctions, one after the other. The common equilibrium type is subgame perfect equilibrium in pure strategies (SPEPS).
When the buyers have full information (i.e., they know the sequence of auctions in advance), and a single item is sold in each round, a SPEPS always exists.
The PoA of this SPEPS depends on the utility functions of the bidders, and on the type of auction used for each individual item.
The first five results below apply to agents with complete information (all agents know the valuations of all other agents):
Case 1: Identical items, two buyers, 2nd-price auctions:
When at least one buyer has a concave valuation function (diminishing returns), the PoA is at most .
Numerical results show that, when there are many bidders with concave valuation functions, the efficiency loss decreases as the number of users increases.
Case 2: additive buyers:
With second-price auctions, the PoA is unbounded – the welfare in a SPEPS might be arbitrarily small!
Case 3: unit demand buyers:
With first-price auctions, the PoA is at most 2 – the welfare in a SPEPS is always at least half the maximum (if mixed strategies are allowed, the PoA is at most 4).
With second-price auctions, the PoA is again unbounded.
These results are surprising and they emphasize the importance of the design decision of using a first-price auction (rather than a second-price auction) in each round.
Case 4: submodular buyers (note that additive and unit-demand are special cases of submodular):
With both 1st-price and 2nd-price auctions, the PoA is unbounded, even when there are only four bidders. The intuition is that the high-value bidder might prefer to let a low-value bidder win, in order to decrease the competition that he might face in the future rounds.
Case 5: additive+UD. Suppose some bidders have additive valuations while others have unit-demand valuations. In a sequence of 1st-price auctions, the PoA might be at least , where m is the number of items and n is the number of bidders. Moreover, the inefficient equilibria persist even under iterated elimination of weakly dominated strategies. This implies linear inefficiency for many natural settings, including:
buyers with gross substitute valuations,
capacitated valuations,
budget-additive valuations,
additive valuations with hard budget constraints on the payments.
Case 6: unit-demand buyers, incomplete information, 1st-price auctions: The BPoA is at most 3.
Auctions employing greedy algorithms
See
Generalized second-price auctions
See
Related topics
Studies on PoA in auctions have provided insights into other settings that are not related to auctions, such as network formation games
Summary table
[Partial table - contains only parallel auctions - should be completed]
References
Auction_theory
Inefficiency in game theory | Price of anarchy in auctions | [
"Mathematics"
] | 2,618 | [
"Game theory",
"Inefficiency in game theory",
"Auction theory"
] |
53,494,176 | https://en.wikipedia.org/wiki/List%20of%20largest%20biomedical%20companies%20by%20revenue | The following is a list of independent pharmaceutical, biotechnology and medical companies listed on a stock exchange (as indicated) that have generated a revenue of at least , ranked by their revenue in the respective financial year.
It does not include biotechnology companies that are now owned by, or form a part of, larger pharmaceutical groups.
Ranking by revenue
The following table lists the largest biotechnology and pharmaceutical companies ranked by revenue in billion USD. The change column indicates the company's relative position in this list compared to its relative position in the preceding year; i.e., an increase would be moving closer to rank 1 and vice versa. Green cells indicate years where revenue increased compared to the preceding year. Red cells indicate those years when there has been a decrease.
See also
List of largest biomedical companies by market capitalization
References
Biotechnology
Biomedical | List of largest biomedical companies by revenue | [
"Engineering",
"Biology"
] | 165 | [
"Biotechnology organizations",
"Biotechnology companies"
] |
53,496,177 | https://en.wikipedia.org/wiki/Cable%20protection%20system | A cable protection system (CPS) protects subsea power cables against various factors that could reduce the cable's lifetime, when entering an offshore structure.
When a subsea power cable is laid, there is an area where the cable can be subjected to increased dynamic forces the cable is not necessarily designed to withstand over its lifetime.
Cable protection systems allow the specification, and thus cost, of a subsea power cable to be reduced by removing the need for additional armoring. Cables can be produced more cheaply, whilst still providing the 20-plus-year lifetime required.
Offshore windfarm developers have widely adopted cable protection systems due to the dynamic areas where the cable leaves from the seabed and enters the monopile/J-tube, in part due to the potential for localised scouring to occur near the structure.
A CPS generally consists of three sections: a Centraliser or Monopile interface, a protection system for the dynamic area, and a protection system for the static area.
The installation of J-Tubes for offshore renewable monopiles was viewed as a costly approach, and a 'latching' type of cable protection system which penetrates the outer wall of the monopile, via a specifically designed angled aperture enables the simplification of monopile design, and removes the need for additional works post pile driving which usually involved the use of divers. This approach has become an industry standard in monopile design, assisting developers to reduce their costs for construction.
History
Articulated half-pipe Cable protections systems have traditionally been used for the protection of cables at shore landings, and other areas where cable damage could be envisaged, and burial was not practical. Patents for variations of articulated pipe cable protections date back to 1929. The system was described as a cable armor shield
"adapted to protect the cable from damage and wear occasioned by rubbing on rocks, contacting with ships, anchors or other objects, and has for its object to provide a practical flexible armor shield of this class which can be readily applied to the cable at any point along its length."
From their outset cable protection systems were designed to be simple, effective, and easy to assemble. The systems consisted of a series of half shells which had a convex flange at one end and a larger socket flange at the other allowing the sections to form a flexible universal joint connection between them. Due to the intended use of heavy cast or forged metals they also had the added advantage of increasing the weight of the cable being installed, thus reducing movement on the seabed.
Over the years innovations have occurred improving the articulation of the joints with modern articulated pipes being more akin to ball-joints, and some manufacturers providing 'boltless' articulated pipes, thus saving assembly time.
Changes in the metallurgy have also happened, leading to most half shell articulated pipe now being made from ductile iron, due to its improved strength and elasticity characteristics.
Today these articulated pipes are also utilised for their bend restriction properties, allowing them to be utilised as bend restrictors for the protected cable.
Design considerations
Cable protection systems are predominantly designed to protect the system from damage throughout the lifetime of the cable caused by fatigue, overbending of the cable, and to provide protection of the cable until it reaches an area of burial.
Design life
The cable protection system will be designed to provide protection for a specific lifetime, the 'design life' of the system, which may vary dependent upon the conditions encountered.
Fatigue of CPS/cable within
Subsea cable protection systems can encounter wear due to movement, and general changes in composition due to being submerged for a prolonged period of time, such as corrosion or changes in polymer based compounds. Consideration should be given to the induced effects on the CPS resulting from the dynamic elements in the environment. Simple changes such as changes in temperature, current or salinity can result in changes in the ability of the CPS to offer protection for the life of the cable. It is advisable to carefully assess the potential effects of movement of the CPS, relating to the dynamic abilities of the cable. The CPS may withstand the worst conditions seen over a 100yr period, but would the cable inside the CPS survive these movements. In some instances, such as shore ends for fibre optic cables where rocky outcrops are present, dynamic influences can be reduced by securing the articulated pipe to the seabed rock, thus reducing the degree of movement remaining.
Some manufacturers have performed independent empirical testing, utilising the DMZC facility at the university of Exeter in the UK, to provide a simulated 25yr life cycle of the dynamic forces applicable to their product in order to provide customers with improved confidence in the survivability of the system.
Another cause for failure of subsea power cables is caused by overheating, which can occur where a cable is contained within a CPS without adequate ability to dissipate the heat produced by the cable. These lead to early fatigue of the cable insulation, necessitating the replacement of the cable.
Subsea cable incidents account for around 77% of the total global cost of wind farm losses. Since 2007 this percentage, which has varied between 70% and 80%, is statistically reported year after year.
Seabed stability
Seabed stability is an important factor associated with cable protection systems. Should the cable protection system be too buoyant, it is less likely to remain in contact with the seabed, thus the CPS is more likely to require additional remedial stability measures, such as installation of concrete mattresses, rockbags, or rockdumping.
Suspension strength
When a CPS is being installed to interface with a monopile structure, there is likely to be seabed scouring to some degree. Should the scouring become excessive, the CPS may be suspended within a scour hole, and needs to be capable of supporting its own weight, and that of the cable within. Failure to sustain this loading scenario will lead to failure of the CPS, which will in turn allow the forces to act upon the cable within, ultimately leading to cable damage.
Installation
Within the renewables market in particular, installation of CPS's are preferred to be completely diverless, as this reduces the developers cost, and removes risk to human life through diving in a hazardous area.
Removal/Reinstallation
A final consideration for CPS is that of removal of the cable should a failure occur. Some designs require diver intervention to recover the cable with the CPS. Due consideration should also be given to the removal of a CPS should the CPS itself fail. The costs associated with CPS replacement during the operational lifetime of an offshore wind farm are not insignificant, as the cable will most likely require repair/replacement as part of the process.
Bend restrictors
Various innovative systems have been developed to provide restriction of bending, including ductile iron articulated pipe, and polymer or metal based vertebrae systems. Vertebrae bend restrictors are available in both metal and polymer based forms. Some cable protection systems include a polymer based vertebrae system which restricts the bend radius to a maximum of a few degrees per segment. These systems are lighter (in water) than their metal equivalents and often more expensive to produce but must be carefully assessed for longevity in the proposed application. Due to the use of polymers these systems tend to be of a larger diameter than their metal counterparts, which presents a larger surface area for drag induced forces caused by currents.
Bend stiffeners
Bend stiffeners are conically shaped polymer mouldings designed to add local stiffness to the product contained within, limiting bending stresses and curvature to acceptable levels. Bend stiffeners are generally suitable for water depths of 35 metres or less, and their suitability is highly dependent on currents and seabed conditions at site. Extreme care must be taken when selecting a stiffener, especially relating to the lifespan of the system as these themselves can become fatigued/fragile. As the stiffness of these products are dependent upon the nature of the plastic used, careful testing and QA of plastics should be carefully considered as flaws introduced during material manufacture, processing, machining and molding.
Other systems
Various other polymer based systems have been developed which provide a flexible 'tube' which can be attached to the structure in advance of the cable being installed, although these are relatively new to the industry, and considered by some as unproven.
Applicable Standards
Although there are no specific standards for cable protections systems, DNVGL-RP-0360 Subsea power cables in shallow water includes a section on Cable Protection at the interface to a structure (Section 4.7).
Offshore Wind - CPS Issues
The use of CPS systems to protect offshore wind power cables has suffered from various CPS failures, resulting in costly repair of CPS systems and the power cables they were to protect. The exact extent, cost and frequency of occurrence of these failures is generally not disclosed, however there have been exceptions including announcements from developer/operator companies such as Orsted of the extent and anticipated repair costs of these.
References
Coastal construction
Submarine communications cables
Telecommunications equipment | Cable protection system | [
"Engineering"
] | 1,839 | [
"Construction",
"Coastal construction"
] |
53,497,061 | https://en.wikipedia.org/wiki/Freebore | In firearms, freebore (also free-bore, free bore, or throat) is the portion of the gun barrel between the chamber and the rifled section of the barrel bore. The freebore is located just forward of the chamber neck and is cylindrical in shape. The diameter of the freebore is larger than the groove diameter of the gun barrel bore so that no rifling is present and projectiles used in the firearm can accelerate through the freebore without resistance.
Location and dimensions
The chamber is the rearmost portion of a firearm barrel that has been formed to accept a specific handgun/rifle cartridge or shotgun shell. For firearms having a rifled barrel, the bullet typically extends forward from the leading edge of the cartridge case. The portion of the barrel forward of the chamber that provides clearance for the loaded bullet of a cartridge is known as the throat. The throat is composed of both a freebore and a leade. The freebore is slightly larger in diameter than the rifling grooves in order to allow the cartridge to be loaded into the chamber without resistance, as well as to increase the distance the bullet can move before it engages the rifling in the bore. The leade is the tapered section of the throat that transitions in diameter from the freebore to the rifling lands at a shallow angle, typically between 1° and 3° degrees.
Freebore length affects the distance the bullet will jump before engaging the rifling when the weapon is fired. Greater freebore length permits bullets to extend further out of the cartridge case to increase space for propellant within the case. Increasing freebore length in order to increase bullet jump is used to delay the onset of resistance from friction and deformation that results when the bullet engages the rifling. Dimensions of freebore length and diameter may gradually increase as hot gas wears the interior barrel surface each time the weapon is fired.
Sources
Firearm components | Freebore | [
"Technology"
] | 396 | [
"Firearm components",
"Components"
] |
53,497,560 | https://en.wikipedia.org/wiki/Weed%20science | Weed science is a scientific discipline concerned with plants that may be considered weeds, their effects on human activities, and their management "a branch of applied ecology that attempts to modify the environment against natural evolutionary trends.".
History
Weeds have existed since humans began settled agriculture have existed since the advent of settled agriculture around 10,000 years ago it has been suggested that the most common characteristic of the ancestors of our presently dominant crop plants is their willingness—their tendency to be successful, to thrive, in disturbed habitats, mostly those around human dwellings. Farmers have likely always been aware of weeds in their crops, although the evidence for their awareness and concern is nearly all anecdotal.
Unlike other agricultural sciences like entomology or plant pathology, the emergence of weed science is comparatively recent, occurring largely within the 20th century and coinciding with the development of herbicides.
Weeds are controlled in much of the world by hand (roguing) or with crude hoes. The size of a farmer's holding and yield per unit area are limited by several things and paramount among them is the rapidity with which a family can weed its crops. More human labor may be expended to weed crops than on any other single human enterprise, and most of that labor is expended by women. Weed control in the Western world and other developed areas of the world is done by sophisticated machines and by substituting chemical energy (herbicides) for mechanical and human energy. There is a relationship between the way farmers control weeds and the ability of a nation to feed its people. Successful weed management is one of the essential ingredients to maintain and increase food production.
In 1923, Clark and Fletcher suggested that the "annual losses due to the occurrence of pernicious weeds on farm land in Canada, although acknowledged in a general way, are far greater than is realized." They thought this was because "farmers gave little critical attention to the weeds growing among their crops." They did not deny that farmers were aware of the weeds only that they could do little about them. Many of the same weeds described by Clark and Fletcher are shown in most current weed identification books. In spite of continued research to mitigate weeds annually many of the same species continue to be problematic.
The first U.S. Congressional appropriation for weed control was made in 1901 for work on control of johnsongrass, 23 years after Congress had appropriated funds for work on cotton insect pests. Petroleum-based herbicides were first used on California crop land in 1924 and soon became widely accepted in Southwestern states. In 1942, oils were used extensively for weed control in carrots and subsequently were used in forest nurseries. French scientists sprayed apple trees with dinitro dyes to control mosses, algae, and lichens. Some noticed that grasses that were wet from the spray did not die and that observation, or, more likely, a series of observations, led to the use of dinitros as herbicides for selective control of broadleaved weeds in cereals and flax. Sinox (sodium dinitro cresylate) was developed by Pastac in 1933. It was the first selective organic herbicide introduced in the US. From the early 1930s until about 1945, it was used extensively in grains, clover hay, grass seed crops, peas, cane berries, onions, and lawns.
Timmons, writing in 1970 reported that "available literature indicates that relatively few agricultural leaders and farmers became interested in weeds as a problem before 1200 A.D. or even before 1500 A.D." The “critical attention” Clark and Fletcher thought was absent increased slowly, primarily because the general attitude seemed to be that “weeds were a curse which must be endured, and about which little could be done except by methods which were incidental to crop production, and by laborious supplemental hand methods."
Jethro Tull, in 1731, appealed for greater attention to weeds:
It is needless to go about to compute the value of the damage weeds do, since all experienced husbandmen know it to be
very great, and would unanimously agree to extirpate their whole race as entirely as in England they have done the wolves, though much more innocent and less rapacious than weeds.
Farmers however were bound by their inability to do much about weeds except by laborious hand methods.
Insects cause both human health and crop problems. Weeds, with a few exceptions, do not cause direct harm to humans. Those that do such as poison ivy and poison oak can be avoided. Poisonous weeds have never been widespread as a weed of crops nor of great concern to the majority of people. Many weeds aggravated human allergies but many did not and other common plants are also allergenic. Insects and insecticides were respectively causes of and solutions to human disease problems. Weeds and herbicides were not and less attention was paid to them. Weeds and herbicides were agricultural problems. They were not of general societal concern. There were a few scientists interested in the study of weeds and in developing techniques to reduce the crop losses caused by weeds. There were only three full-time weed experts in 1934 and only a few part-time ones.
By late 1951, 46 state agricultural experiment stations had active weed research programs and most of them were working on weed control with herbicides. Now all colleges of agriculture in land-grant universities have weed scientists and a well-developed weed management program.
Weed science has been strongly influenced by herbicides and mechanical technology developed by supporting industries, by research by weed scientists, and, ultimately, used by farmers. Herbicides greatly expanded the opportunities and range of methods for vegetation management and weed control. The definition accepted by the Weed Science Society of America (WSSA) is “A chemical substance or cultured biological organism used to kill or suppress the growth of plants.”
Weed scientists have tended to focus on results and progress. Modern agriculture in the world's developed nations has addressed but not eliminated most weed problems through extensive use of herbicides and the more recent development of herbicide resistant crops through genetic modification. These methods while undeniably successful for their intended purpose also have created environmental, non-target species, and human health problems. Farmers in the world's developing nations use some herbicides but newer herbicides and the necessary application technology are often unavailable or too expensive. Weeds are always present in these farmer's fields but often the most available, affordable control methods are mechanical weeding, usually with animal power, or by hand, and most of the labor is provided by women. Neither the hypothesis that more energy is expended for the weeding man's crops than for any other single human task nor the corollary hypothesis that women do most of the world's weeding has been verified, but they are widely accepted.
Weed science no longer focuses exclusively on agriculture, with applications in industrial activities like maintaining railroad rights-of-way, controlling invasive species (including aquatic weeds) in natural areas and sports/park/home lawn care
Objectives of Weed Science
Management of particularly troublesome weeds
While any plant can be a weed, approximately 250 plant species are sufficiently troublesome, cosmopolitan and economically injurious to warrant targeted research into their biology to assist in their management and control. Examples of some of these troublesome weed species in North America are Palmer amaranth (Amaranthus palmeri S. Watson), common lambsquarter (Chenopodium album L.), horseweed (Erigeron canadensis L.), morningglory (Ipomoea spp.), waterhemp (Amaranthus tuberculatus (Moq.) J. D. Sauer) and common ragweed (Ambrosia artemisiifolia L.). Some weed science researchers provide extension resources for farmers and land managers by trialing a variety of weed control tools and tactics on a specific weed, publishing the results and providing recommendations for their future management. Other researchers may study the biology of weed seeds in order to determine how long weed seeds can remain viable in a soil. Much of this research is conducted at public land-grant universities.
Herbicide application and interaction
Another aspect of weed science research is concerned with generating knowledge about the active ingredients of herbicides. Specifically, evaluating the response of weeds and crops to different combinations of herbicides at varying rates, droplet sizes, and environmental conditions within different cropping systems containing different weed communities. Some herbicides become more effective when mixed together (syngerism), while other herbicide combinations reduce the overall control (). Some weed science researchers trial a variety of herbicides applications and combinations on weeds to evaluate their impact on the weeds and crops. Most of this research is conducted by private companies.
Herbicide fate and action
Another aspect of weed science is concerned with how herbicides move in the environment after they are applied. Some herbicides degrade very quickly in sunlight and can be made inactive before entering the plant while others can persist for years in the soil after they are applied, causing problems for future crops. Registering herbicides can cost hundreds of millions of dollars in order to demonstrate how the chemical moves and degrades within the environment it is applied. Most of this research is conducted by private companies in order to be able to register their products for sale.
Professional Societies
Many professional societies exist for weed scientists to publish research findings and support future research. The Weed Science Society of America (WSSA) is a non-profit professional society that hosts annual conferences and regional conferences in the United States as well as provides guidance on the use of herbicides. For example, the WSSA created a categorization system of herbicides by mode of action that is adopted by all herbicide manufacturers to clearly communicate the way in which each herbicide product impacts plant physiology. By encouraging herbicide applicators to use different modes of action, this reduces the likelihood of herbicide resistant populations of weeds from occurring, thereby stewarding the long-term ability of these weed control products.
Many other professional societies exist for weed science that support the current research challenges of a given country or region. For example, the Indian Society of Weed Science, the Weed Science Society of Japan, and more.
References
Branches of botany
Horticulture | Weed science | [
"Biology"
] | 2,074 | [
"Branches of botany"
] |
53,498,042 | https://en.wikipedia.org/wiki/Aphaenogaster%20dlusskyana | Aphaenogaster dlusskyana is an extinct species of ant in the subfamily Myrmicinae known from a single Middle Eocene fossil found in amber on Sakhalin. At the time of description A. dlusskyana was one of eight ant species known from Sakhalin fossil.
History and classification
A. dlusskyana is known from a single adult female fossil, the holotype, specimen number "PIN3387-172" which, at the time of the genus description, was residing in the Paleontological Institute, Russian Academy of Sciences, in Moscow. The described specimen is a worker caste adult preserved as an inclusion in a transparent chunk of Sakhalin amber. The amber specimen was recovered from deposits on Sakhalin island, in far eastern Russia during a 1972 collecting expedition. The expedition recovered amber from the beaches of the Okhotsk Sea at the mouth of the Naiba River and upstream on the banks of the river eroding out of exposures of Naibuchi Formation strata.
Sakhalin amber has been attributed a range of geological ages, with Vladimir Zherikhin in 1978 suggesting dates between 59 and 47 million years old. In 1988, Gennady Dlussky suggested a tentative Paleocene age, which was followed by subsequent authors through 2013. Research published in 1999 on the Naibuchi Formation, in which Sakhalin amber is directly preserved, however, gives a Middle Eocene age based on geological and paleobotanical context. The Sakhalin amber forest had a variety of plants living in a mixed coastal swamp, river, and lake environment. The river and lake system had numerous swampy areas that resulted in active peat bog formation. The bogs were surrounded by Osmunda, Nymphaeaceae and Ericaceae plants, while Taxodium, Alnus, Salix, and other trees populated the forest.
The amber fossil specimen was first studied by paleoentomologists A. G. Radchenko and E. E. Perkovsky of the National Academy of Sciences of Ukraine, with their 2016 type description for the species being published in the Paleontological Journal. The species name was coined as a patronym honoring the Russian paleoentomologist and myrmecologist Gennady Dlussky, who had died in 2014. Radchenko and Perkovsky suggested in the description that A. dlusskyana was the oldest described Myrmicinae species belonging to a living genus of the subfamily. They noted older fossils are reported in the literature, but no detailed descriptions of the specimens have been published.
A. dlusskyana has a pair of distinctive long spines near the rear of her propodeum that are not seen in any of the late Eocene European amber species, or in any Upper Eocene United States amber species. Workers of two amber species, Aphaenogaster amphioceanica from Miocene Dominican amber and Aphaenogaster praerelicta from Late Oligocene to Early Miocene Mexican Amber have similar spines. A. dlusskyana is separated from A. praerelicta in the shape of the spines, which widen near the base in A. praerelicta, in the more rounded petiole of the A. dlusskyana, and overall size, with A. praerelicta workers being more than longer. A. amphioceanica has a very elongated head that does not have distinct rear corners, rather the rear margin forms a "collar" shape, features not seen in the A. dlusskyana worker.
Description
The single worker of A. dlusskyana has a long body and a long head. The body has a number of long hairs scattered on it, with a large amount present on the upper surface of the gaster, while the tarsi have a dense covering of hairs that lie almost flat and curl upward at the tips. There is coarse parallel ridging running the length of the mesosoma, and the gaster, waist, and head are smooth with no surface sculpturing. The head is rectangular in outline, being 1.3 times as long as wide and with very slightly convex sides. The rear margin of the head also is slightly convex and the rear corners are "narrowly" rounded. Two lobes are well developed toward the front of the head, and partly cover the bases of the antennae and antennal sockets. The antennae are composed of 12 segments, each of the segments being elongated, and the last four at the tip forming a club. At the base, the scape is elongated and one third of its length projects past the rear edge of the head. On each of the triangular shaped mandibles, the inner chewing surface is 80 percent as long as the whole mandible length.
References
dlusskyana
Eocene insects
Fossil taxa described in 2016
Hymenoptera of Asia
Sakhalin amber
Cenozoic insects of Asia
Fossil ant taxa
Species known from a single specimen | Aphaenogaster dlusskyana | [
"Biology"
] | 1,019 | [
"Individual organisms",
"Species known from a single specimen"
] |
53,498,449 | https://en.wikipedia.org/wiki/Hajra%20Waheed | Hajra Waheed is a Montréal-based artist. Her multimedia practice includes works on paper, collage, sound, video, sculpture and installation. Waheed uses news accounts, extensive research and personal histories to critically examine multiple issues including: covert power, mass surveillance, cultural distortion and the traumas of displacement caused by colonialism and mass migration.
Waheed was born in 1980 in Canada. She has complex ties and relationships to North America, the Middle East and South Asia. She grew up within the gated compound of Saudi ARAMCO in Dhahran. She studied at the Art Institute of Chicago where she received her BFA in advanced painting and art history, in 2002. She moved to Montréal in 2005 and completed her MA at McGill University in 2007. At 34, Waheed received the Victor Martyn Lynch-Staunton Award for Outstanding Achievement as a Canadian Mid-Career Visual Artist. She was shortlisted for the Sobey Art Award in 2016.
Waheed's works are in the collections of the Museum of Modern Art, the British Museum, the Devi Art Foundation, Samdani Art Foundation, the Musée d'art contemporain de Montréal and the National Gallery of Canada.
Exhibitions
(In) The First Circle, Antoni Tàpies Foundation, Barcelona (2012)
Lines of Control, Herbert F. Johnson Museum of Art, Ithaca, (2012)
Field Notes and Other Backstories, Art Gallery of Windsor, Windsor, (2013)
Collages: Gesture and Fragments, Musée d'art contemporain de Montréal, Montréal, (2014)
Lines of Control, The Nasher Museum of Art, Duke University, (2014)
La Biennale de Montréal, Musée d'art contemporain de Montréal, Montréal, (2014)
Asylum in the Sea, Fonderie Darling, Montréal, 2015
Still Against the Sky, KW Institute for Contemporary Art, London, (2015)
The Missing One, Dhaka Art Summit, Dhaka, (2016)
Sobey Art Award Exhibition, National Gallery of Canada, Ottawa, (2016)
The Eighth Climate (What Does Art Do?), 11th Gwangju Biennale, Gwangju, (2016)
Sea Change - Chapter 1, Character 1: In the Rough, Mosaic Rooms, London (2016)
The Cyphers, BALTIC Centre for Contemporary Art, Gateshead, (2016)
Farewell Photography, Biennale für aktuelle Fotografie, Kunstverein Ludwigshafen, Ludwigshafen, (2017)
Turbulent Landings: NGC Canadian Biennial, Art Gallery of Alberta, Edmonton, (2017)
Viva Arte Viva, Venice Biennale, Venice, (2017)
The Video Installation Project, Musée d'art contemporain de Montréal, Montréal, (2017)
Hold Everything Dear, The Power Plant, Toronto, (2019)
References
External links
1980 births
Living people
School of the Art Institute of Chicago alumni
McGill University alumni
21st-century Canadian artists
Multimedia artists
Women multimedia artists | Hajra Waheed | [
"Technology"
] | 598 | [
"Multimedia",
"Multimedia artists"
] |
54,767,236 | https://en.wikipedia.org/wiki/Maths%20Pathway | Maths Pathway is an online educational website based in Melbourne, used in Australian schools to teach mathematics. It differs from traditional mathematics, as it is set up in a modular format, with students working on individual pieces of learning on a computer and worksheet. These tests are read on a laptop, and written on paper.
History
Maths Pathway was created in 2015 by Richard Wilson and Justin Matthys, who were concerned about a student decline in mathematics skills. The development started as a small website headquartered in a shed in Matthys' lawn. According to the website, it is featured in over 250 schools and used by 57,000 students.
Features
Maths Pathway uses a modular format where students select their work based on what proficiency level they are at, as opposed to every student completing the same tasks. Students are then required to be tested on what they have learned every fortnight. To use Maths Pathway, schools must pay a hefty fee for each student.
Criticism
Maths Pathway has been criticised for the ease at which students can cheat, doable by simply clicking to check your answer or waiting a while after switching the format to PDF, leading to students not learning the modules that the software believes that they have learnt. At the beginning of 2023, in an effort to stop cheating, Maths Pathway launched a large update, which added Entrance Tickets, to review maths before you learn it, Exit Tickets, to prove that you learnt the module, and added a timer requiring questions to be answered after 5 seconds, to "ensure" that the student writes down their working, however this does not work as well as thought, as the student can still skip through modules, just slower.
References
External links
Educational math software
Australian companies established in 2015
Internet properties established in 2015
Australian educational websites
Online companies of Australia
Privately held companies of Australia
Companies based in Melbourne
Education companies of Australia
B Lab-certified corporations in Australia | Maths Pathway | [
"Mathematics"
] | 388 | [
"Educational math software",
"Mathematical software"
] |
54,770,850 | https://en.wikipedia.org/wiki/LeoSat | LeoSat was a satellite constellation project by a Luxembourg-based company of the same name in 2013–2019. It aimed to provide high-speed, broadband satellite internet for corporate and government clients willing to pay premium price for high-quality service.
The constellation was conceptually designed to consist of 78 to 108 satellites in a 1400 km orbit. Each satellite would have weighed around 1000kg (satellite mass changed as designs were updated in the course of the project). Ka band was to be used for downlink. The total cost of the project was estimated in 2017 to be €3.0 to €3.1 billion (US$3.5 to 3.6 billion).
In May 2017, SKY Perfect JSAT Group announced it would invest in LeoSat. In 2018, Spanish satellite operator Hispasat also invested into LeoSat.
LeoSat had a deadline of Jan 2021 to launch a satellite in order to activate the ITU filing by their partner Thales Alenia Space.
In November 2019, LeoSat shut down operations after failing to find sufficient investment capital to pursue the large speculative project. All 13 employees of the company (the company never had substantially more than a dozen employees) were laid off. LeoSat never launched a single satellite.
Some of the investors in earlier rounds have spoken publicly on why they left the LeoSat project.
References
External links
Official LeoSat website
Proposed communications satellite operators
Companies of Luxembourg
2013 establishments in Luxembourg
21st-century disestablishments in Luxembourg | LeoSat | [
"Astronomy"
] | 302 | [
"Outer space stubs",
"Outer space",
"Astronomy stubs"
] |
54,773,609 | https://en.wikipedia.org/wiki/Letters%20on%20Sunspots | Letters on Sunspots (Istoria e Dimostrazioni intorno alle Macchie Solari) was a pamphlet written by Galileo Galilei in 1612 and published in Rome by the Accademia dei Lincei in 1613. In it, Galileo outlined his recent observation of dark spots on the face of the Sun. His claims were significant in undermining the traditional Aristotelian view that the Sun was both unflawed and unmoving. The Letters on Sunspots was a continuation of Sidereus Nuncius, Galileo's first work where he publicly declared that he believed that the Copernican system was correct.
Previous observations of sunspots
Galileo was not the first person to observe sunspots. The earliest apparent reference to them appears in the I Ching of ancient China, while the earliest recorded observation is also Chinese, dating to 364 BC. Around the same time, the first European mention of sunspots is found, by Theophrastus. There were reports from Islamic and European astronomers of sunspots in the early ninth century; those occurring in 1129 were recorded by both Averroes and John of Worcester, whose drawings of the phenomenon are the earliest surviving today. Johannes Kepler observed a sunspot in 1607 but, like some earlier observers, believed he was watching the transit of Mercury. The sunspot activity of December 1610 was the first to be observed using the newly invented telescope, by Thomas Harriot, who sketched what he saw but did not publish it. In 1611 Johannes Fabricius saw them, and published a pamphlet entitled De Maculis in Sole Observatis, which Galileo was not aware of before he wrote the Letters on Sunspots.
Critical dialogue with Scheiner
When Jesuit Christoph Scheiner first observed sunspots in March 1611, he ignored them until he saw them again in October. Then, under the pseudonym Apelles latens post tabulam (Apelles hiding behind the painting), he presented his description and conclusions about them in three letters to the Augsburg banker and scholar Mark Welser. Scheiner wanted to remain anonymous to avoid involving the Jesuit order and the church generally in an area of controversy. Welser published them on his own presses, sent copies to astronomers around Europe, and invited them to reply. It was Welser's invitation which prompted Galileo to reply with two letters, arguing that the sunspots were not satellites, as Scheiner ('Apelles') maintained, but were features either on the Sun's surface or just above it.
In the meantime, Scheiner sent Welser two further letters on the subject, and after he had read Galileo's first letter, he responded with a sixth of his own. These later letters were different in tone from the first three, as they hinted that Galileo was claiming credit for having discovered the phases of Venus, when in fact proper credit was due to others. They also implied that Galileo had copied Scheiner's helioscope in order to do his research.
Having published Scheiner's first three letters under the title Tres Epistolae de Maculis Solaribus ("Three Letters on Solar Spots"), Welser now published his second three, also in 1612, as De Maculis Solaribus et Stellis circa Iovis Errantibus Accuratior Disquisition ("A More Accurate Disquisition Concerning Solar Spots and Stars Wandering around Jupiter"). Having read these second three letters, Galileo replied with a third of his own, much sharper and more polemical in tone than his earlier ones. Welser declined to publish Galileo's letters, perhaps because of the sarcastic tone they took towards Apelles, although the reason he gave Galileo was the exorbitant cost of producing all the illustrations Galileo wanted.
Censorship by the Inquisition
Publishing the Letters on Sunspots was a major financial and intellectual venture for the Accademia dei Lincei, and it was only the fourth title it had decided to issue. Federico Cesi paid for the publication himself, and wanted to strike a careful balance between introducing extraordinary new ideas and avoiding causing offence to people who might find those views problematic. This was consistent with the Accademia's project of acting as a centre for the dissemination of radical new scientific ideas, issued with the agreement of the Church authorities. Cesi tried to persuade Galileo to avoid an aggressive or polemical tone in his letters, to avoid antagonising the Jesuits (Scheiner's identity behind the pseudonym 'Apelles' was already suspected), but having read Scheiner's apparent accusations of bad faith in his later letters, Galileo did not heed his advice. Indeed, the published version of his Letters on Sunspots contained a preface by Angelo de Filiis which uncompromisingly asserted Galileo's primacy in discovering sunspots. The text was presented for censorship to the Roman Inquisition in order to obtain permission to print. The censors assigned were Cesare Fidelis, Luigi Ystella, Tommaso Pallavicini and Antonio Bucci.
Ensuring the book was ready to print was a collaborative process involving the censors, Galileo, Cesi and others in working on the text until it was acceptable to the Inquisition, and the censors were well acquainted with the leading figures of the Accademia. Antonio Bucci, for example, was a physician who had previously been involved in reviewing work by Giambattista della Porta, also published by Cesi. In the case of Letters on Sunspots his critical support appears to have been helpful in ensuring that publication was not prevented by influential Dominicans of the Sacred Palace. Indeed, in his comments Bucci praised Galileo's work, with which he was already familiar, as he had been invited to take part in the Accademia's discussions about it before the manuscript was presented for censorship.
The censors insisted that Galileo remove from his text any reference to scripture or claims for divine guidance. Thus the pamphlet was to have opened with a quotation from Matthew 11:12 'The kingdom of heaven suffers violence, and men of violence take it by force.' The censors objected that this could be understood to mean that astronomers wanted to overpower theology. It was therefore amended to 'Already the minds of men assail the heavens, and the more valiant conquer them.' Further on in the text Galileo's claim that 'divine goodness' had led him to advocate the system of Copernicus was struck out, and replaced with 'favourable winds'. Galileo's text referred to the idea that the heavens were immutable as 'erroneous and repugnant to the indubitable truth of Scripture.' Like all other mentions of Scripture, the censors insisted that this too was removed. Galileo wanted to claim divine inspiration for his findings and show how they accorded with Holy Writ; the censors wanted to keep unusual new ideas at a safe distance from core tenets of the faith. With these amendments Galileo was authorised to take his book to print.
Half of the printed edition of 1400 copies of Letters on Sunspots contained both the Apelles Letters and Scheiner's illustrations as well as Galileo's replies. The other half contained Galileo's work only. The total cost of the book was 258.70 scudi, of which 44 scudi was the cost of the illustrations and tables and 6 scudi was the cost of engraving the frontespiece.
Galileo's First Letter - 4 May 1612
Galileo describes how he has observed sunspots for eighteen months. His key conclusions are that sunspots were real and not merely optical illusions; and that they were not static, but moved. The sunspots had a single motion, moving across the Sun in a uniform fashion. Galileo argued that the Sun was a perfect sphere and that it moves by itself on its own center. The Sun carries these spots until they disappear from view at its rim in about one lunar month.
Scheiner's view that the spots were satellites prompts Galileo to comment on the phases of Venus and how they supported a heliocentric view. He develops his argument to show that sunspots were not permanent and did not have a regular pattern of movement as they would if they were heavenly bodies – they were nothing like the moons of Jupiter that he had himself discovered and described in Siderius Nuncius. 'The sun, turning on its axis, carries them around without necessarily showing us the same spots, or in the same order, or having the same shape.' He noted the parallels between sunspots and clouds over the Earth, but did not assert that they were made of the same material. His comment on 'Apelles' (the pseudonym of Scheiner) was:'It seems to me therefore that Apelles has a free, and not a servile mind; he is well able to grasp true teaching; and now, prompted by the strength of so many new ideas, he is beginning to listen and to assent to true and sound philosophy, especially as regards the arrangement of the universe. But he is not yet able to detach himself completely from the fantasies he absorbed in the past, to which his intellect sometimes returns and lends assent by force of long-established habit.'
Much of Galileo's first letter is devoted to demonstrating weaknesses in Scheiner's arguments – inconsistencies, false analogies, and unlikely conclusions from the observations he had made.
Responding to points in Apelles' first letter
Apelles says the sunspots move from east to west, when he should have said they moved from west to east. This is not in fact a disagreement about the direction of the spots, but a reminder of the conventions used by astronomers to describe them. From the point of view of the Earth, the sunspots move to move from east to west, but astronomers describe celestial movement from the 'highest' (i.e. furthest away from the Earth) point of their cycles.
Apelles has not conclusively demonstrated that the spots cannot be on the surface of the Sun, simply by asserting that because it is bright, it cannot have dark parts.
Apelles is wrong to say that sunspots are much darker than dark spots on the Moon; the spots are in fact not as dark as the area immediately around the Sun which is most strongly illuminated by it, and this area is itself so bright that the Moon would be invisible if we tried to observe it in that position.
Responding to points in Apelles' second letter
Apelles discusses the transit of Venus but is wrong about the size of the planet relative to the Sun; it is so much smaller than Apelles suggests that it may not even be possible for observers to see it making its transit, meaning that the lack of a definite sighting of the transit does not necessarily prove anything. (Scheiner had argued that since a transit of Venus was predicted but not seen, this must mean that Venus had passed behind the Sun, thereby lending support to Tycho Brahe's view that Venus, like all planets apart from the Moon, orbited around the Sun).
Responding to points in Apelles' third letter
Apelles reports that sunspots took around fifteen days to pass across the face of the Sun, and that he never saw the same spots re-emerge on the eastern limb of the Sun fifteen days after they disappeared on the western limb. He concludes that they could not therefore be features carried around the Sun on its surface by a regular rotation. Galileo responds that this would be the case if Apelles had shown that the spots were solid bodies, whereas it is obvious to observers that they are changing shape as they move around the Sun. He therefore says that Apelles has not proved that they could not be on the surface of the Sun.
Apelles arguments are inconsistent. When considering his failure to observe a transit of Venus, he concludes that Venus must be behind the Sun (which was possible in Tycho Brahe's model of the universe but impossible in Ptolemy's); however when discussing parallax, in a later part of his argument, he claims that Venus only displays a small parallax (required in Ptolemy's system but impossible in Brahe's).
Apelles argues that the spots are not in any of the 'orbs' of the Moon, Venus or Mercury; but according to Galileo these 'orbs', like deferents and epicycles, were only theoretical devices of 'pure astronomers' and not actual physical entities. 'Philosophical astronomers' have no interest in such concepts but are concerned with trying to understand how the universe actually works. Apelles does not even argue consistently on the basis of his assumptions that these orbs and other suppositional devices actually exist, for he says first that if the spots were phenomena in the 'orbs' of the Moon, Venus or Mercury (which only appear to us to be on the face of the Sun) then they would have to move with motion of those planets. However having concluded that the spots are in the 'orb' of the Sun, he maintains that they do not move with the motion of the Sun, but independently of it.
Galileo then offers a different explanation to the one Apelles had suggested for the fact that as the sunspots approach the limb of the Sun in their rotation, they grow thinner. Apelles had included a diagram in his third letter to demonstrate how he believed this could be explained in terms of the spots being small moons, which went through phases. Galileo maintained that this was doubtful. As the dark area of sunspots approach the limb of the Sun, it appears from observation that the area of darkness reduces from the side facing away from the Sun – i.e. that the spots are actually getting thinner. If they were moons, the area of darkness would diminish from the side facing the centre of the Sun.
Galileo points out inconsistencies in the arguments by Apelles which, in one place, would mean the spots had to be very close to the Sun, and, in another part, that they must be far away from it. The differences in speed between spots moving near the Sun's equator and those further away from it argue for their being on the surface, as the larger the notional 'orb' outside the Sun the spots might be carried on, the less visible this difference in speed would be.
Galileo considers the possible 'essence' or substance of the sunspots, and says he does not believe there is yet any way of knowing it. He shows however that of all the things we observe on Earth, it is clouds that share the most characteristics with sunspots. Whatever they may be made of, they are certainly not 'stars' as Apelles suggests, since, as he himself shows, they cannot be observed making regular orbits of the Sun.
Apelles had tried to make the case that the sunspots were similar to two phenomena Galileo had discovered, the moons of Jupiter and the rings of Saturn. Galileo responds that there is no comparison in either case; the moons of Jupiter (Medicean Stars) move with an absolute regularity he has already described, while Saturn simply bears no comparison to the description Apelles provides of it. (Here Galileo provides two simple in-line sketches to show what he means). Galileo assures his reader that he can confirm, after long observation, that Saturn never changes its shape, as Apelles claims, and never will.
Mercury, the planet closest to the Sun, completes its transit in about six hours; it makes no sense to propose that spots on some 'orb' which is much closer to the Sun than Mercury would take around fifteen days to complete theirs. Likewise planetary orbits appear constant in their speed, whereas Apelles has shown that sunspots move rapidly in the centre of the Sun but more slowly at its edges.
Galileo's Second letter – 14 August 1612
Galileo's second letter restates the key propositions from his first letter, and is otherwise mostly concerned with geometric proofs that the spots are on the surface of the Sun rather than above it. To accompany these proofs Galileo provides 38 detailed illustrations, which allow the reader to see how his observations relate to his calculations.
Further observations confirm what Galileo originally believed – that the spots were on or very close to the Sun, which carries them round as it rotates on its own axis.
He notes that as sunspots approach the limit of their movement cross the visible field of the Sun, at the point where they are seen 'sideways on' from Earth, they sometimes appear as thin as a thread; if, as Apelles maintained, the spots were satellites, they would be clearly set apart from the surface of the Sun at this point.
The apparent acceleration of the spots as they approach the centre of the Sun and their slower speeds towards the edges, are perfectly consistent with a circular rotation on the surface. The growth in apparent size of the gaps between spots as they approach the centre, and their apparent diminution towards the edges of the Sun, likewise confirm this.
He uses a geometrical diagram to demonstrate the effects of foreshortening, showing how if the sunspots were removed from the surface of the Sun by even a twentieth part of its diameter, there would be a very observable difference in the visible foreshortening effect. The apparent distance to the observer from C to F is seven times smaller than the actual distance on the surface of the Sun from C to H; however, if the spots are just a small way above the surface of the Sun, the apparent distance from C to F corresponds to the actual distance from R to N, which is less than a third the length of C to H. Thus by measuring the differences in the apparent distances between spots as they move across the Sun, it is possible to know with certainty whether the foreshortening corresponds to the proportion CF:CH or to some other proportion. The changes in apparent distance observed leave no doubt on this question.
He uses a second diagram to demonstrate the gaps between sunspots which can be seen right up to the point where they disappear at the limb of the Sun. This, he says, means they must be low against the sun and thin, rather than high above its surface and thick.
Galileo then counters a number of arguments that might be put forward to show that sunspots are an effect in the Earth's atmosphere. These were not arguments Apelles had advanced; rather, he had also argued against them. Galileo's points were made for the sake of completeness, although, as he argues 'it is not necessary to waste time in re-examining every other conceivable position [for the sunspots], for anyone will immediately encounter manifest impossibilities and contradictions himself, so long as he has understood the phenomena I have recounted above.'.
He says that because the spots change shape, it is difficult to be certain whether some complete a full revolution and reappear in changed form after disappearing round to the dark side of the Sun for fourteen or fifteen days. However he believes that this does in fact happen. 'I am inclined to this belief upon seeing a very large one appear and grow continuously while the visible hemisphere turns; since it is credible that it was generated long before its arrival, so it is reasonable to believe that it can last after its departure, such that its duration will be much longer than the time of half a revolution of the Sun. Therefore, some spots can doubtless, or rather necessarily, be seen twice by us.
He considers arguments about the natural inclination of bodies for different kinds of motion in order to judge whether the spots are on the surface of the Sun or in its atmosphere, and concludes that the regularity of sunspot motion argues that they 'originate in a solid and firm body where the motion of the whole and of the parts is a single one.' (However, in his Third Letter he argued, against Scheiner, that 'there is no one so simple as to grant that the Sun is hard and immutable').
He describes his method of observing and recording sunspots, discovered by Benedetto Castelli. This is by way of explaining to the reader that the thirty-eight illustrations which follow are highly accurate (i.e. unlike Scheiner's).
His last main point addresses those who say that his ideas and observations contradict Aristotle. 'If he argued for the immutability of the heavens because in times past no alteration whatsoever had been seen in them, it is entirely credible that if vision had demonstrated to him the things that it makes manifest to us, he would have arrived at the opposite conclusion. And I will further say that I think I contradict Aristotle's doctrine much less... with the supposition of mutable celestial material, than do those who would prefer to treat it as inalterable, because I am sure that he was never as certain of the conclusion of inalterability as he was of the notion that all human discourse must defer to evident experience.'
He adds a postscript to say that while he was undertaking his observations, a sunspot appeared which was so large it could be seen with the naked eye between 19 and 21 August 1612. This is included in his series of illustrations.
Galileo's Third Letter – 1 December 1612
While Galileo's First and Second Letters had been written in response to Scheiner's Tres Epistolae, his Third Letter responded to Accuratior Disquisitio. Galileo was angry to see that once again Scheiner was making claims about the moons of Jupiter, since he regarded them as his own discovery. To demonstrate the falsehood of Scheiner's assertion that the moons of Jupiter were 'wandering stars', unpredictable in their movement, as well as to display his own clear superiority in observation and calculation of celestial movements, Galileo appended a complete set of Ephemerides for the Jovian moons to his third letter. Galileo shows the critical flaws in Scheiner's geometry, his understanding of the authorities he cites, his reasoning, his observations and indeed his own drawings.
Introduction
Galileo says there is no point in speculating about the 'essence' of sunspots, or indeed of other things, but since writing his last letter he has spent time thinking about the uniform motion of the sunspots within a specific band around the Sun's surface. He asks, in passing, 'is there not still a controversy over whether the Earth itself remains immobile, or wanders?', which is an oblique reference to the idea, required by Copernicus' model of the universe, that the earth must rotate on its own axis every day. Lastly, he humorously compares scholars who insist that every detail of Aristotle's writing must be true, whether it corresponds with reality or not, with those artists who draw portraits of people in fruit and vegetables. 'As long as these oddities are offered as jokes, they are nice and pleasing... but if someone, perhaps because he had consumed all his studies in a similar style of painting, then wanted to draw the general conclusion that every other method of imitating was imperfect and blameworthy, surely Cigoli and other celebrated painters would laugh at him.'
Venus, sunspots and use of authorities
Galileo takes up once again the question of whether there is any relation between the transit of Venus and sunspots. He criticises 'Apelles' for setting out a long and complex demonstration of the movement of Venus across the face of the Sun, when it was superfluous to his purpose. He criticises him further for giving an estimate of Venus's size as it crosses the Sun which is wrong, and for supporting this estimate with learned authorities from the past who did not have telescopes. Furthermore, Galileo argues, some of the ancient astronomers, including Ptolemy, made more cogent arguments than 'Apelles' suggests.
Galileo notes that 'Apelles' has shifted his view on sunspots since his first letter. At first he insisted they were all spherical, like little moons; now he says they are irregular in shape, forming and dissolving. He previously said that the spots were at various distances from the Sun, wandering between it and Mercury, but he no longer maintains this view. 'Apelles' argues that the hardness and solidity of the Sun means that the fluid spots cannot be on its surface; but citing the authority of the ancients to confirm the Sun's solidity is pointless, since they had no idea of its structure; in any case the evidence of the spots themselves suggests the very opposite to the traditional view of the Sun's hardness. He agrees with 'Apelles' view that the spots are not chasms or pools on the Sun's surface, but nobody had ever argued that they were.
The movement of sunspots
A large portion of the Third Letter is taken up with disproving Apelles' assertion that he had observed spots passing across the Sun at different speeds – one, on the diameter, taking sixteen days, and another, at a lower latitude, in just fourteen. (If sunspots moved at differential speeds, this tended to suggest they were moons moving independently of the Sun itself). Galileo says that in his own observations he has never seen this differential rate of movement, but that spots always move at a constant speed relative to each other. First Galileo demonstrates that points on two different sunspot trajectories at two different latitudes produce lines which maintain a constant proportion with each other at any point in the rotation. Next he shows that the larger the sphere on which sunspots appear, the less differential there is in their transit times at the same two latitudes. Finally, he shows that for a spot to move along the diameter of the Sun in a period 1 as long as another spot at a latitude 30° higher, the diameter of the Sun would need to be more than twice as great as observed. From this he concludes that Apelles is simply wrong, and it is not possible for one spot to traverse the Sun in sixteen days, while another takes only fourteen.
Now Galileo turns to Apelles' illustrations of sunspots, and begins to use them to show how his arguments about sunspot motion are false. He recalls how Apelles depicts them coming into view, foreshortened, before appearing at their full width. He then demonstrates that for the spots Apelles had observed to change in apparent size as they did, they would need to be on the face of the Sun, because if they were even a short distance above its surface the foreshortening effect would be remarkably different. Galileo challenges Apelles' assertion that he had seen different spots moving at different speeds; particularly that he had seen spots on the Sun's diameter rotate more rapidly than those at higher latitudes. This, he says, is contradicted not only by observation but by Apelles' own statement in another place in his work that spots in the middle of the Sun remain longer than those passing nearer its limb. Finally, Apelles' own illustrations clearly show spots transiting the Sun in around 14 days, and nothing in his illustrations supports his contention that some take 16, and others 9.
Observations on other planets
Having disproved Apelles' arguments on sunspots, Galileo addresses a number of his other errors. He briefly responds to Apelles' views on extraterrestrial life; then disposes of the idea that the Moon is translucent. He then returns to Apelles' analogy between sunspots and the moons of Jupiter, where he notes that Apelles has subtly moved from arguing that sunspots are like planets, to arguing that planets are like sunspots. 'Carried away by the desire to maintain what he had originally said, and unable to accommodate the spots exactly to the properties once associated with the other stars, [Apelles] has accommodated the stars to the properties that we know belong to the spots.' To dispense once and for all with Apelles' claim that the moons of Jupiter 'appear and disappear', Galileo provides predictions for their positions for the next two months to prove the regularity of their motions.
To demonstrate that natural philosophy must always be led by observation and not try to fit new facts into preconceived frameworks, Galileo comments that the planet Saturn had recently and surprisingly changed its appearance. In his First Letter, he had argued that Saturn never changes its shape, and never will. Now, he agrees, it has changed shape. He does not try to prove his earlier views right in spite of new facts, but makes cautious predictions about how its appearance may change in future.
Galileo concludes his remarks by criticising those who doggedly adhere to Aristotle's views, and then, drawing together all he has said about sunspots, the moons of Jupiter, and Saturn, ends with the first explicit endorsement of Copernicus in his writings:
I think it is not the act of a true philosopher to persist – if I may say so – with such obstinacy in maintaining Peripatetic conclusions that have been found to be manifestly false, believing perhaps that if Aristotle were here today he would do likewise, as if defending what is false, rather than being persuaded by the truth, were the better index of perfect judgement... [and] I say to your Lordship that this star too [i.e. Saturn] and perhaps no less than the emergence of the horned Venus, agrees in a wondrous manner with the harmony of the great Copernican system, to whose universal relations we see such favourable breezes and bright escorts directing us.
Significance of Letters on Sunspots
Ideas
The common belief until Galileo's time was that the heavens beyond the Moon were both perfect and unchanging. Many of the arguments between Scheiner and Galileo were about things observed in the skies that appeared to be changing, and what the nature and significance of that change was. Although the behaviour of sunspots was the main topic of their debate, they also touched on other disputes, such as the phases of Venus and the moons of Jupiter.
In a letter to Federico Cesi, Galileo said:
'I have finally concluded, and I believe I can demonstrate necessarily, that they [i.e. the sunspots] are contiguous to the surface of the solar body, where they are continually generated and dissolved, just like clouds around the earth, and are carried around by the sun itself, which turns on itself in a lunar month with a revolution similar [in direction] to those other of the planets... which news will be I think the funeral, or rather the extremity and Last Judgement of pseudophilosophy.... I wait to hear the spoutings of great things from the Peripatetics to maintain the immutability of the skies.'
'Flaws' in the Sun
The cosmology of Galileo's time, based on Aristotle's Physics, held that the Sun was 'perfect' and unflawed. Only with the invention of the telescope was it possible for sunspots to be systematically observed. Many who had never seen them found the idea of them morally and philosophically repugnant. Those who could see them, like Scheiner, wanted to find an explanation for them within the Aristotelian system. Galileo's arguments in Letters on Sunspots were intended to demonstrate these claims as false; and if they were false, Aristotelian assumptions about the universe could not be true.
Moons of Jupiter
Galileo had discovered the moons of Jupiter in 1609. Scheiner argued that what appeared to be spots on the Sun were in fact clusters of small moons, thereby trying to deploy one of Galileo's own discoveries as an argument for the Aristotelian model. In his Letters on Sunspots Galileo showed how sunspots were nothing like the moons of Jupiter, and the comparison was false. Scheiner claimed that the sunspots, with their irregular movements, were like the moons of Jupiter whose positions were similarly hard to predict. To counter this argument, Galileo published tables of predictions for the future position of the moons of Jupiter, so that astronomers could easily distinguish between the regular, predictable movements they followed with the ephemeral and irregular sunspots.
Rotation of the Sun
Showing that the Sun rotated had two effects. Firstly, it showed that the traditional Aristotelian model of the universe must be wrong, because that model assumed that the Sun had only a diurnal (daily) motion around the earth, and not a rotation on its own axis. Secondly, it showed that there was nothing necessarily unusual about rotation of a body in space. In the Aristotelian system, night and day were explained by the Sun moving round a static Earth. For Copernicus' system to work, there had to be an explanation for why half the Earth was not in permanent daylight, and the other in permanent darkness, as it completed its annual motion around the Sun. This explanation was that the Earth rotated on its own axis once every day. However it was very difficult to prove that the Earth was rotating, so to show that the Sun rotated made the Copernican model at least more plausible. While the rotation of the Sun did not prove Copernicus right, it proved his opponents wrong and made his ideas more likely to be true.
Phases of Venus
In the Letters on Sunspots Galileo responded to claims by Scheiner about the phases of Venus, which were an important question in the astronomy of the time. There were different schools of thought about whether Venus had phases at all – to the naked eye, none were visible. In 1610, using his telescope, Galileo had discovered in that Venus, like the Moon, had a full set of phases, but only in Letters on Sunspots did he commit this finding to publication. The fact that there was a full phase of Venus, (similar to a full moon) when Venus was in the same direction in the sky as the Sun meant that at a certain point in its orbit, Venus was on the other side of the Sun to the Earth. This indicated that Venus went around the Sun, and not around the Earth. This provided important evidence in support of the Copernican model of the universe.
Copernicus
At least as early as 1597, Galileo had concluded that the Copernican model of the universe was correct but had not publicly advocated this position. In Siderius Nuncius Galileo included in his dedication to the Grand Duke of Tuscany the words ' while all the while with one accord they [i.e. the planets] complete all together mighty revolutions every ten years round the centre of the universe, that is, round the Sun.' In the body of the text itself, he stated briefly that in a forthcoming work, 'I will prove that the Earth has motion', which is an indirect allusion to the Copernican system, but that is all. Copernicus is not mentioned by name. It is at the end of the Third Letter that Galileo explicitly declares his belief in the Copernican system.
Movement of the Sun
Galileo remarks in one passage that the Sun might not be revolving, but in another he states more definitely that the Sun does have a motion, and wonders what causes it. Here he establishes a connection between cosmology and mechanics. Galileo wrote, "I seem to have observed that physical bodies have physical inclination to some motion." Letters in Sunspots is also the first of his works to mention the concept of inertia, which would later become Newton's First Law of Motion.
Language
While Scheiner wrote his letters in Latin, Galileo's reply was in Italian. Scheiner did not speak Italian, so Welser had to have Galileo's letters translated into Latin so he could read them. This was not the first time Galileo had published in Italian, and Galileo was not the first natural philosopher to publish in Italian (for example Lodovico delle Colombe's account of the 1604 supernova was in Italian, as was Galileo's reply). However Letters on Sunspots was the first book the Accademia dei Lincei published in Italian. Galileo later said of his preference for Italian over Latin:
'I wrote in Italian because I wished everyone to be able to read what I wrote.... I see young men.... who, although furnished.... with a decent set of brains, yet not being able to understand things written in gibberish [i.e. Latin], take it into their heads that in these crabbed folios there must be some grand hocus-pocus of logic and philosophy much too high up for them to think of jumping at. I want them to know, that as nature has given eyes to them, just as well as to philosophers, for the purpose of seeing her works, she has also given them brains for examining and understanding them.'
While Scheiner's lack of Italian hindered his response to Galileo in 1612 while they corresponded through Welser, it also meant that when Galileo published Il Saggiatore in 1623, which accused Scheiner of plagiarism, Scheiner was unaware of this until he happened to visit Rome the following year.
Use of diagrams and illustrations
Most readers of the time did not have a telescope, so could not see sunspots for themselves – they relied on descriptions and illustrations to make clear what they looked like. For this reason the quality and number of illustrations was essential in building public understanding. Scheiner's book of letters had contained illustrations of sunspots which were mostly 2.5 cm in diameter, leaving little space for detail and portraying sunspots as solid, dark entities. Scheiner himself had described them as 'not terribly exact' and 'drawn without precise measurement'. He also indicated that his drawings were not to scale, and the spots in his illustration had been drawn disproportionately large 'so that they would be more conspicuous.' A reader looking at these illustrations might be inclined to agree with Scheiner's view that sunspots were probably planets.
Although the sunspots were constantly changing position, Scheiner presented his observations over a period of six weeks in a single fold out plate. All of his figures are small except for the observations in the top left corner. He admitted to his readers that his drawings were not made to scale, and that other factors such as variations in the weather, lack of time, or other impediments may have reduced their accuracy. Scheiner also showed the formation of spots in different orientations. Sometimes the configurations of the spots were linear following consecutive days, but the orientations became more complex over time that there was a lack of an obvious pattern.
For Galileo to persuade his readers that sunspots were not planets but a much more transient and nebulous phenomenon, he needed illustrations which were larger, more detailed, more nuanced, and more 'natural.' Letters on Sunspots carried 38 engravings of sunspots, providing a visual narrative of the sun's appearance from 2 June – 8 July 1612, with some additional illustrations from August. This extensive visual representation, with its large scale and high-quality reproduction, allowed readers to see for themselves how sunspots waxed and waned as the sun rotated. The impact of this series of illustrations was to create a near-photographic sense of reality. This sense undermined the claims made by Scheiner before any argument was mounted to refute them.
Galileo and Prince Cesi selected Matthaeus Greuter to create the sunspot illustrations. Originally from Strasbourg and a convert from Protestantism, Greuter moved to Rome and set up as a printer specialising in work for the Jesuit order. His work ranged from devotional images of saints through to mathematical diagrams. This relationship may have recommended him as one whose involvement in a publication would perhaps ease its path through censorship; in addition his craftsmanship was outstanding, and he devised a novel etching technique specially in order to make the sunspot illustrations as realistic as possible. Galileo drew sunspots by projecting an image of the Sun through his helioscope onto a large piece of white paper, on which he had already used a compass to draw a circle. He then sketched the sunspots in as they appeared projected onto his sheet. To make his illustrations as realistic as possible, Greuter reproduced them at full size, even with the mark of the compass point from Galileo's original. Greuter worked from Galileo's original drawings, with the verso on the copperplate and the image traced through and etched.
The cost of the thirty-eight copperplates was significant, amounting to fully half of the production costs of the edition. Because half the copies of the Letters also contained the Apelles Letters, Greuter reproduced the illustrations that Alexander Mair had done for Scheiner's book, allowing Galileo's readers to compare two distinct views of the sunspots. He reduced Mair's drawings further in size, and converted nine of the twelve from etchings or engravings into woodcuts, which lacked the subtlety of Mair's originals. Scheiner was evidently impressed by Greuter's work, as he commissioned him to create the illustrations for his own magnum opus Rosa Ursina in 1626. The 1619 work Galileo co-wrote with Mario Guiducci, Discourse on Comets, mocked Scheiner for the 'badly colours and poorly-drawn images' in his work on Sunspots.
Making predictions to test a hypothesis
In modern science falsifiability is generally considered important. In De revolutionibus orbium coelestium Copernicus had published both a theoretical description of the universe and a set of tables and calculating methods for working out the future positions of the planets. In Letters on Sunspots Galileo did as Copernicus had done – he elaborated his ideas on the form and substance of sunspots, and accompanied this with tables of predictions for the position of the moons of Jupiter. In part this was to demonstrate that Scheiner was wrong in comparing sunspots with the moons. More generally, Galileo was using his predictions to establish the validity of his ideas – if he could be demonstrably right about the complex movements of many small moons, his readers could take that as a token of his wider credibility. This approach was the opposite of the method of Aristotelian astronomers, who did not build theoretical models based on data, but looked for ways of explaining how the available data could be accommodated within existing theory.
Scholarly reception
Some astronomers and philosophers, such as Kepler, did not publish views on the ideas in Galileo's Letters on Sunspots. Most scholars with an interest in the topic divided into those who supported Scheiner's view that sunspots were planets or other bodies above the surface of the Sun, or Galileo's that they were on or very near its surface. From the middle of the seventeenth century the debate about whether Scheiner or Galileo was right died down, partly because the number of sunspots was drastically reduced for several decades in the Maunder Minimum, making observation harder. After the Paris Observatory was built in 1667, Jean-Dominique Cassini instituted a programme of systematic observations, but he and his colleagues could find little pattern in the appearance of sunspots after many years of observation. However Cassini's observation did bear out Galileo's argument that sunspots indicated that the Sun was rotating, and Cassini did discover the rotation of Mars and Jupiter, which supported Galileo's contention that both the Earth and the Sun rotated.
Christoph Scheiner
As Cesi had feared, the hostile tone of the Letters on Sunspots towards Scheiner helped turn the Jesuits against Galileo. In 1619, Mario Guiducci published A Discourse on Comets, which was actually mostly written by Galileo, and which included an attack on Scheiner, although its focus was the work of another Jesuit, Orazio Grassi. In 1623, Galileo wrote Il Saggiatore (The Assayer), which accused Scheiner of trying to steal Galileo's ideas.
In 1624, on a visit to Rome, Scheiner discovered that in The Assayer, Galileo had accused him of plagiarism. Furious, he decided to stay in Rome and devote himself to proving his own expertise in sunspots. His major work on the topic was Rosa Ursina (1626–1630). It is widely believed, though there is no direct evidence, that the bitter dispute with Scheiner was a factor in bringing Galileo to trial in 1633, and indeed that Scheiner may have worked behind the scenes to bring the trial about. As a result of pursuing this dispute with Galileo and the years of research it entailed, Scheiner eventually became the world's leading expert on sunspots.
Raffaelo delle Colombe
Together with Niccolò Lorini and Tommaso Caccini, delle Colombe was one of three Florentine Dominicans who opposed Galileo. Along with Raffaelo's brother Lodovico delle Colombe they formed what Galileo called the 'Pigeon League'. Caccini and delle Colombe both used the pulpit to preach against Galileo and the ideas of Copernicus, but only delle Colombe is known to have preached, on two separate occasions, against Galileo's ideas about sunspots. The first occasion was 26 February 1613, when his sermon concluded with these words:
'That ingenious Florentine mathematician of ours [i.e. Galileo] laughs at the ancients who made the sun the most clear and clean of even the smallest spot, whence they formed the proverb 'to seek a spot on the sun.' But he, with the instrument called by him a telescope makes visible that it has regular spots, as by observation of days and months he had demonstrated. But this more truly God does, because 'the heavens are not of the world in His sight'. If spots are found in the suns of the just, do you think they will be found in the moons of the unjust?'
The second sermon against sunspots was on 8 December 1615, when the Letters on Sunspots had already been referred to the Inquisition for review. The sermon was delivered in Florence cathedral on the Feast of the Immaculate Conception.
'an ingenious academic took for his device a mirror in the face of the sun with the motto 'it shows what is received'. That means he had carved in his spirit I do not know what kind of beloved sun. But what would be better for Mary? Who could fixedly look at the infinite light of the Divine Sun, were it not for this virginal mirror, that in itself conceives it [the light] and renders it to the world? 'Born to us, given to us from an intact virgin?' This is 'Let what is received, be shown'. For one who seeks defects where there are none, is it not to be said to him 'he seeks a spot in the sun?' The sun is without spot, and the mother of the sun is without spot, from where Jesus is born.'
The Roman Inquisition
On 25 November 1615, the Inquisition decided to investigate the Letters on Sunspots because it had been mentioned by Tommaso Caccini and Gianozzo Attavanti in their complaint about Galileo. Copies of the text were issued to the Inquisition's theological experts on 19 February 1616. On the morning of 23 February they met and agreed two propositions to be censured (that the Sun is the centre of the world, and that the Earth is not the centre of the world, but moves). Neither proposition is contained in Letters on Sunspots. Shortly after the decision of the Inquisition, the Congregation of the Index placed Copernicus' De Revolutionibus on the Index. Letters on Sunspots was however not banned or required to undergo corrections. This meant that while Catholic scholars could no longer discuss heliocentrism, they could discuss the nature and origin of sunspots freely.
Francesco Sizzi
In 1611, before the Letters on Sunspots appeared, Francesco Sizzi had published Dianoia Astronomica, attacking the ideas of Galileo's earlier work, Siderius Nuncius. In 1612 he went to Paris and devoted himself to the study of sunspots. In 1613 he wrote to Galileo's friend Orazio Morandi, confirming that his circle of colleagues in France agreed with Galileo that sunspots were not freshly generated with each revolution of the Sun, but could be observed passing round it several times. Furthermore, Sizzi drew to Galileo's attention something he had not yet noticed – that the inclination of the path travelled by sunspots varied with the seasons. Thus in one part of the year the sunspots appeared to be travelling upwards across the face of the Sun; in another part of the year they appeared to be travelling downward. Galileo was to adopt this observation and deploy it in his Dialogue Concerning the Two Chief World Systems in 1632 to demonstrate that the Earth tilted on its axis as it orbited the Sun.
Johannes Kepler
In his work Phaenomenon singulare (1609) Kepler had described what he took to be the transit of Mercury, observed on 29 May 1607. However, after Michael Maestlin pointed out Galileo's work to him, he corrected himself in 1617 in his Ephemerides, recognising long after the event that what he had seen was sunspots. Welser sent Kepler a copy of Scheiner's first three Apelles letters, and Kepler replied before Galileo, arguing, like him, that Sunspots must be on the surface of the Sun and not satellites. Kepler reached this conclusion only by studying the evidence Scheiner's had provided, without making any direct observations of his own. Kepler did not however engage with the claims of Galileo in "Letters on Sunspots" or have further involvement in public discussion on the question.
Michael Maestlin
In his treatise on the comet of 1618, Astronomischer Discurs von dem Cometen, so in Anno 1618, Michael Maestlin made reference to the work of Fabricius and cited sunspots as evidence of the mutability of the heavens. He made no reference to the work of either Scheiner or Galileo, although he was aware of both. He concluded that sunspots are definitely on or near the Sun, and not a phenomenon of the Earth's atmosphere; that it is only thanks to the telescope that they can be studied, but that they are not a new phenomenon; and that whether they are on the surface of the Sun or move around it is a question to which there is no reliable answer.
Jean Tarde
The French churchman Jean Tarde visited Rome in 1615, and he also met Galileo in Florence and discussed sunspots with him, as well as Galileo's other work. He did not agree with Galileo's view that the sunspots were on or near the surface of the Sun, and held rather that they were small planets. On his return to France in 1615 he built an observatory at La Roque-Gageac where he studied sunspots further. In 1620 he published Borbonia Sidera, dedicated to Louis XIII, in which he declared the spots to be the 'Bourbon planets'.
Charles Malapert
The Belgian Jesuit Charles Malapert agreed with Tarde that the apparent sunspots were in fact planets. His book, published in 1633, was dedicated to Philip IV of Spain and christened them 'Austrian stars' in honour of the house of Habsburg.
Pierre Gassendi
Pierre Gassendi made his own observations of sunspots between 1618 and 1638. He agreed with Galileo that the spots were on the surface of the Sun, not satellites orbiting it. Like Galileo, he used observation of the spots to estimate the speed of the Sun's rotation, which he gave as 25–26 days. Most of his observations were not published however and his notes were not kept systematically. He did however discuss his findings with Descartes.
Rene Descartes
René Descartes was interested in sunspots and his correspondence shows that he was actively gathering information about them when he was working on Le Monde. He was aware of Scheiner's Rosa Ursine published in 1630, which conceded Galileo's point that sunspots are actually on the face of the Sun. Whether he knew of Galileo's ideas primarily through Scheiner or whether he read Letters on Sunspots directly is not known, but in his Principles of Philosophy (1644) he refers to "spots which appear on the sun's surface also revolve around it in planes inclined to that of the ecliptic", which appears to indicate at least a knowledge of Galileo's argument. Descartes used sunspots as an illustration of his Vortex Theory.
Giovanni Battista Riccioli
In his 1651 work Almagestum Novum, Giovanni Battista Riccioli set out 126 arguments against the Copernican model of the universe. In his 43rd argument, Riccioli considered the points Galileo had made in his Letters on Sunspots, and asserted that a heliocentric (Copernican) explanation of the phenomenon was more speculative, while a geocentric model allowed for a more parsimonious explanation and was thus more satisfactory (ref: Occam's Razor).
As Riccioli explained it, whether the Sun went round the Earth or the Earth round the Sun, three movements were necessary to explain the movement of sunspots. If the Earth moves around the Sun, the necessary movements were the annual motion of the Earth, the diurnal motion of the Earth, and the rotation of the Sun. However, if the Sun moved around the Earth, this accounted for the same movement as both the annual and diurnal motions in the Copernican model. In addition, the annual gyration of the Sun at its poles, and the rotation of the Sun had to be added to completely account for the movement of sunspots. While both models required three movements, the heliocentric model required the Earth to make two movements (annual and diurnal) which could not be demonstrated, while the geocentric model was based on three observable celestial movements, and was accordingly preferable.
Athanasius Kircher
Athanasius Kircher succeeded Scheiner in the Chair of Mathematics at the Collegio Romano. In Mundus Subterraneus (1664), he rejected the views of both Scheiner and Galileo, reviving an earlier idea of Kepler's and arguing that sunspots were in fact smoke emanating from fires on the surface of the Sun, and that the surface of the Sun was therefore indeed perfect as the Aristotelians believed, although apparently disfigured by blemishes. Sunspots, he argued, just like the planets in astrology, had a profound influence on the Earth.
Sunspots in Galileo's later writings
The Assayer
In Il Saggiatore (The Assayer) (1623) Galileo was mostly concerned with faults in Orazio Grassi's arguments about comets, but in the introductory section he wrote :
'How many men attacked my Letters on Sunspots, and under what disguises! The material contained therein ought to have opened to the minds eye much room for admirable speculation; instead it met with scorn and derision. Many people disbelieved it or failed to appreciate it. Others, not wanting to agree with my ideas, advanced ridiculous and impossible opinions against me; and some, overwhelmed and convinced by my arguments, attempted to rob me of that glory which was mine, pretending not to have seen my writings and trying to represent themselves as the original discoverers of these impressive marvels.'
Christoph Scheiner took this to be an attack on him. He therefore used Rosa Ursina to mount a bitter riposte to Galileo, although he also conceded Galileo's main point, that sunspots exist on the Sun's surface or just above it, and thus that the Sun is not flawless.
Dialogue Concerning the Two Chief World Systems
In 1632 Galileo published Dialogo sopra i due Massimi Sistemi del Mondo (Dialogue Concerning the Two Chief World Systems), a fictitious four day-long discussion about natural philosophy between the characters Salviati (who argued for Copernican ideas and was effectively a mouthpiece of Galileo), Sagredo, who represented the interested but less well-informed reader, and Simplicio, who argued for Aristotle, and whose arguments were possibly a parody of those made by Pope Urban VIII. The book was reviewed by the Roman Inquisition and in 1633 Galileo was interrogated and found 'vehemently suspect of heresy' because of it. He was forced to renounce his belief in heliocentrism, sentenced to house arrest and banned from publishing anything further. The Dialogue was placed on the Index.
The Dialogue is a broad synthesis of Galileo's thinking about physics, planetary movement, how far we can rely on our senses in making judgements about the world, and how we make intelligent use of evidence. It drew together all his findings and recapitulated arguments made in earlier years on specific topics. For this reason, there is no 'section on sunspots' in the Dialogue. Rather, they are referred to at various points in arguments about other topics. In the Dialogue, that sunspots are on the surface of the Sun and not planets was taken as established fact. The discussion concerned what inferences could be drawn about the universe from their rotation. Galileo did not argue that the existence of sunspots conclusively proved that the Copernican model was correct and the Aristotelian model wrong; he explained how the rotation of sunspots could be explained in both models, but that the Aristotelian explanation was much more complicated and suppositional.
Day 1 The discussion opens with Salviati arguing that two key Aristotelian arguments are incompatible; either the heavens are perfect and unchanging, or that the evidence of the senses is preferable to argument and reasoning; either we should rely on the evidence of our senses when they tell us changes (such as sunspots) take place, or we should not. Holding both positions is not tenable.
Day 2: Salviati argues that sunspots prove the rotation of the Sun on its axis. Aristotelians had previously held that it was impossible for a heavenly body to have more than one natural motion. Aristotelians must therefore choose between their determination that only one natural movement is possible (in which case the Sun is static, as Copernicus argued); or they must explain how a second natural motion occurs if they wish to maintain that the Sun makes a daily orbit of the Earth. This argument is resumed on Day 3 of the Dialogue.
See also
Copernican Revolution
List of Catholic clergy scientists
Solar observation
References
External links
(video) Lecture by Paulo Galluzzi, Director of the Museu Galileo, on the involvement of the Accademia dei Lincei in publishing Letter on Sunspots
Galileo's Letters on Sunspots (Rome,1613)
Malapert's Austriaca Sidera Heliocyclia, (Douai, 1633)
Scheiner's Prodromus pro sole mobili et terra stabili contra ... Galilaeum a Galileis (Prague, 1651)
1613 books
1613 in science
Galileo Galilei
Astronomical controversies
History of astronomy | Letters on Sunspots | [
"Astronomy"
] | 12,335 | [
"Astronomical controversies",
"History of astronomy"
] |
54,774,161 | https://en.wikipedia.org/wiki/Maguari%20orthobunyavirus | Maguari orthobunyavirus, abbreviated MAGV, is a negative-sense, single-stranded RNA virus in the Bunyavirales order, genus Orthobunyavirus, Bunyamwera serogroup, that has been shown to be capable of causing human disease. MAGV is related to Cache Valley virus and Tensaw virus.
In addition to humans, MAGV has been isolated from mosquitoes, horses, cattle, sheep, birds, and rodents. The mosquito species include Aedes fulvus, Aedes scapularis, Aedes serratus, Culex taeniopus, and species in the genera Anopheles, Wyeomyia, and Psorophora.
MAGV's geographic range includes Argentina, Brazil, Colombia, French Guiana, Guyana, and Peru.; it has not been isolated north of Trinidad. The presence of antibodies to Maguari virus in human residents of south Florida can be attributed to either cross-reactivity with Tensaw virus, or cross-reactivity to an antigenic subtype or variant of Tensaw virus, although it is possible that another, undescribed, Bunyamwera serogroup virus may exist in south Florida.
References
Orthobunyaviruses | Maguari orthobunyavirus | [
"Biology"
] | 264 | [
"Virus stubs",
"Viruses"
] |
54,775,152 | https://en.wikipedia.org/wiki/Vegetarian%20and%20vegan%20symbolism | Multiple symbols have been developed to represent lacto-vegetarianism and veganism. Several are used on food packaging, including voluntary labels such as The Vegan Society trademark or the V-Label (with support of the European Vegetarian Union) as well as the vegetarian and non-vegetarian marks mandated by the Indian government. Symbols may also be used by members of the vegetarian and vegan communities to represent their identities, and in the course of animal rights activism.
Vegetarian symbols
Indian vegetarian mark
Packaged food and toothpaste products sold in India are required to be labelled with a mandatory mark in order to be distinguished between lacto-vegetarian and non-vegetarian. The symbol is in effect following the Food Safety and Standards (Packaging and Labelling) Act of 2006, and received a mandatory status after the framing of the respective regulations (Food Safety and Standards (Packaging and Labelling) Regulation) in 2011. According to the law, vegetarian food should be identified by a green symbol and non-vegetarian food with a brown symbol. They are defined as:
"Vegetarian food must have a symbol of a green color-filled circle inside a square with a green outline prominently displayed on the package, contrasting against the background on the principal display panel, in close proximity to name or brand name of the food."
"Non-vegetarian food (any food which contains whole or part of any animal including birds, marine animals, eggs, or products of any animal origin as an ingredient, excluding honey, milk or milk products), must have a symbol of a brown color-filled circle inside a square with a brown outline prominently displayed on the package, contrasting against the background on the principal display panel, in close proximity to the name or brand name of the food."
In 2021, FSSAI (Food Safety and Standards Authority of India) adopted a new symbol for non-vegetarian food items due to concerns that the combination of the old symbols were difficult for people with colour blindness to distinguish. The new symbol is that of a brown color-filled triangle inside a square with a brown outline.
In September 2021, the FSSAI announced adoption of the new vegan symbol.
V-Label
The V-Label, a V with a leaf, originated with the European Vegetarian Union. The V-Label is a standardised international vegan and vegetarian label supported by the EVU with the aim of easy identification of vegan and vegetarian products and services.
Vegetarian Society approved trademark
The Vegetarian Society Approved trademark is the world’s first vegetarian accreditation symbol and appears on thousands of products worldwide. It was created in 1969 by the Vegetarian Society who were established in 1847 and invented the word "vegetarian".
Any product displaying the Vegetarian Society Approved vegetarian trademark has been independently checked by the Vegetarian Society and meets these criteria:
Contains no ingredient made from animal body parts
Only free-range eggs are used
Measures in place to avoid cross-contamination during production
GMO-free
No animal testing carried out or commissioned.
Vegan symbols
Vegan Trademark
The Vegan Trademark, with its iconic sunflower, is an internationally recognised standard from The Vegan Society (who coined the term 'vegan'). It certifies products with the aim of easy identification of vegan products. Launched in 1990, it was the first vegan verification scheme.
Enclosed V
The enclosed v (modeled after the enclosed A symbol) is a popular vegan symbol, especially on social networks where it is represented by the Ⓥ symbol of the Enclosed Alphanumerics Unicode block. This lowercase "V" inside a circle is not used to label products as vegan nor should be relied upon to determine if a product is vegan. A kosher organization (Vaad Hoeir of St. Louis) owns and uses a US trademark (certification mark) consisting of an uppercase V inside a circle.
Seedling emoji
On internet forums and social networks, the seedling emoji 🌱 is sometimes used to symbolize veganism or vegan products.
Veganarchy symbol
The Veganarchy symbol, first introduced in print in Brian A. Dominick's Animal Liberation and Social Revolution pamphlet in 1995, combines the Circle-V with the Circle-A of anarchist symbolism.
Vegan flag
The vegan flag was designed in 2017 by a network group of graphic designers and activists from several countries. The group was opened by Gad Hakimi, a vegan activist and designer from Israel. who intended it to be a Civil flag to represent veganism. The flag consists of three blue and green triangles forming the letter V, the first letter in the word "vegan".
Originally, some members of the group suggested that animals should be featured on the flag, with red colours featuring prominently to symbolize the blood of slaughtered animals. However, the group eventually chose to make the flag about human–animal respect, not about animals themselves.
Inspired by the LGBT rainbow flag, the flag was created in hopes of uniting animal rights organizations and activists.
The colours white, green, and blue were chosen to represent the natural habitats of animals: sky, land, and sea. The letter V stands for Vegan, and is an inverted pyramid intended to symbolize the ability to do the impossible.
V-Label
The international V-Label supported by the European Vegetarian Union is an internationally recognised and protected trademark for the labelling of vegetarian and vegan products.
Vegetarian Society Approved vegan trademark
The Vegetarian Society Approved vegan trademark was established in 2017 and appears on thousands of products worldwide. Any product displaying the Vegetarian Society Approved vegan trademark has been independently checked by the Vegetarian Society and has met these criteria:
Contains no animal-derived ingredients
Measures in place to avoid cross-contamination during production
GMO-free
No animal testing carried out or commissioned.
In 2022 McDonald's launched their McPlant burger across the UK, accredited with the Vegetarian Society Approved vegan trademark.
India Introduces Vegan Food Regulations
In 2022, The Food Safety and Standards Authority of India (FSSAI) has put in place first-of-its-kind regulations for vegan food products within the country.
The new rules clearly define what constitutes vegan food and how brands can label it. The logo was designed by a Bengaluru-based, Food Science and Nutrition college student-Kruti Manish Rathore.
See also
List of food labeling regulations
Food Safety and Standards Authority of India
References
External links
The Food Safety and Standards Authority of India
Lists of symbols
Vegetarianism
Veganism
Political symbols | Vegetarian and vegan symbolism | [
"Mathematics"
] | 1,308 | [
"Symbols",
"Lists of symbols"
] |
54,776,521 | https://en.wikipedia.org/wiki/2017%20CloudPets%20data%20breach | CloudPets were a line of Internet-connected soft toys manufactured by now defunct Spiral Toys that was the subject of numerous security vulnerabilities in February 2017. The plush teddy bear-style toys used Bluetooth to connect to a parent's smartphone to allow distant family members to send voice messages to the toy, and allow children to send voice messages back.
Security researchers demonstrated that the toy itself was insecure and could be trivially accessed via Bluetooth. The personal records of over 820,000 owners of the toy were stored in an insecure MongoDB database. Attackers also replaced the database with a ransom demand pointing to a Bitcoin address. Data retrieved from the CloudPets database was sent to the Australian security researcher Troy Hunt who included it in Have I Been Pwned?, a database of users whose data has been compromised. The database of user records also contained links pointing to over 2.2 million audio files hosted on Amazon Web Services containing the voice messages sent to and from the toys. Hunt stated that the database hack was "ridiculously easy".
Following disclosure of security vulnerabilities, CloudPets started enforcing stronger password requirements on users of the service—they had previously not enforced any password complexity requirements and their documentation had suggested short, weak passwords. Numerous journalists and security researchers including Hunt noted that the company was non-responsive to disclosures from security researchers and enquiries from journalists.
See also
Computer security
Internet of things
My Friend Cayla, another Internet-connected children's toy
References
2010s toys
Teddy bears
Hacking in the 2010s
Cyberattacks
Internet of things
Electronic toys
Criticisms of software and websites
Toy controversies | 2017 CloudPets data breach | [
"Technology"
] | 336 | [
"Criticisms of software and websites"
] |
54,777,118 | https://en.wikipedia.org/wiki/Irina%20Antanasijevi%C4%87 | Irina Antanasijević (, ; born 27 June 1965) is a Russian and Serbian philologist, literary critic, and translator. She received her Doctor of philological sciences degree in 2002 and has been a professor of Russian literature at Philology Faculty of University in Belgrade since 2004. Her scholarly interests include folklore and post-folklore, visual literature and visual text, poetics of comics, illustration, children's literature, and history of Russian emigration studies.
Biography
Born in the city of Sievierodonetsk, Luhansk Oblast, Ukrainian SSR, USSR. After arriving to Yugoslavia she lived in Split, and since 1991 till 1999 in Priština. She worked as lecturer, and then as an assistant for Russian literature at Philology Faculty in Priština. She defended her thesis "Landscape in Russian and Serbian Epic" during the NATO bombing of Yugoslavia in 1999.
She left Priština after the signing of Kumanovo Agreement (June 1999) and moved to Niš. She worked as professor of Russian literature at Philosophy Faculty in Niš and continued to work at Philosophy Faculty in Priština (with the seat in Kosovska Mitrovica). In 2002 she defended doctoral thesis Poetics of Dirge. She initiated opening of the Department for Slavistics with Balcanistics at Philology Faculty in Niš (since 2002 Department for Russian language and literature).
Professor of Russian literature at Philology Faculty of University in Belgrade. Member of Editorial Board of journal Gradina until 2009. Member of Editorial Board of periodical Facta universitatis until 2010. Member of Editorial Board of periodical Научный результат, Серия Социальные и гуманитарные исследования (Scientific Result, Series of Social and Humanitarian Studies).
Awards
Medal of Pushkin (Russian Federation, November 24, 2021) – for a great contribution to the promotion of the Russian language and Russian culture in Serbia.
Bibliography
Monographs
Landscape in Russian and Serbian Folk Epics (Пејзаж у руској и српској народној епици), Prosveta, Niš, 2005, , 126 p.
Poetics of Russian Dirges (Поетика руских тужбалица), Prosveta, Niš, 2003, , 210 p.
Folklore and Avant-garde: symbols and phenomena (Фольклор и авангард: символы и явления), Niš, Gradac: Despot Book, 2011, , 253 p.
Russian Comics in the Kingdom of Yugoslavia (Русский комикс Королевства Югославия), Novi Sad, Komiko, 2014, , 340 p.
Russian Classic in Pictures (Русская классика в картинках), Belgrade: Philology Faculty of University of Belgrade, 2015 (Belgrade: Belpak), Библиотека Язык и литература. Серия Русская эмиграция в Белграде ; кн. 7,
Dictionaries
Dictionary of general words and expressions (Лексикон општих речи и израза), Budva, Kuća knjige, 2007 , 753 p.
Dictionary, Russian-Serbian Serbian-Russian (Речник руско-српски српско-руски), Budva, Kuća knjige, 2007 , 832 p.
Phrase book, Russian-Serbian Serbian-Russian (Разговорник руско-српски српско-руски), Budva, Kuća knjige, 2007 , 192 p.
Textbooks and manuals
Russian for students of biology and ecology (Руски језик за студенте биологије и екологије), Niš — Srpsko Sarajevo, 2002, , 190 p.
Russian for students of physics (Руски језик за студенте физике), Niš — Srpsko Sarajevo, 2001, UDK: 808. 2:53(075. 8), 185 p.
References
External links
Irina Antanasijević, a full bio-bibliography (Ирина Антанасијевић, био-библиографија), Project Rastko – Russia (Serb)
Personal page at Academia.edu
1965 births
Living people
People from Sievierodonetsk
Russian philologists
Serbian philologists
Linguists of Slavic languages
Serbian translators
Russian translators
Serbian folklorists
Russian folklorists
Russian women folklorists
Women philologists
Serbian people of Russian descent
Russian studies scholars
Linguists from Serbia
Serbian educators
Serbian women folklorists
Textbook writers
Women textbook writers
Women science writers
Women linguists
21st-century philologists
21st-century linguists
21st-century women scientists
21st-century Serbian educators
Serbian women educators
21st-century Serbian women writers
21st-century women educators
21st-century translators
Russian people of Serbian descent | Irina Antanasijević | [
"Technology"
] | 1,230 | [
"Women science writers",
"Women in science and technology"
] |
54,777,700 | https://en.wikipedia.org/wiki/SECS-I | The SECS-I (SEMI Equipment Communications Standard, Part 1), sometimes called SEMI E4, provide the syntactical details (like frame formats, etc.) for communication between a semiconductor manufacturing equipment and a host machine. SECS-I works on RS 232 based serial links and define how the communications are transmitted over RS-232C. HSMS (High Speed SECS Message Services) provides the corresponding specification for Ethernet-based networks.
References
Communications protocols | SECS-I | [
"Technology"
] | 97 | [
"Computer standards",
"Communications protocols"
] |
54,777,955 | https://en.wikipedia.org/wiki/Phragmoplastophyta | The Phragmoplastophyta (Lecointre & Guyader 2006) are a proposed sister clade of the Klebsormidiaceae in the Streptophyte/Charophyte clade. The Phragmoplastophyta consist of the Charophyceae and another unnamed clade which contains the Coleochaetophyceae, Zygnematophyceae, Mesotaeniaceae, and Embryophytes (land plants). It is an important step in the emergence of land plants within the green algae. It is equivalent to the ZCC clade/grade, cladistically granting the Embryophyta.
The mitosis of Phragmoplastophyta takes place via a phragmoplast.
Another synapomorphy of this clade is the synthesis of cellulose microfibrils by a complex of octameric cellulose synthetases. This complex crosses the plasma membrane and polymerizes molecules from the cytoplasm into cellulose microfibrils, which, together with each other, form fibrils, necessary in the formation of the wall. The Phragmoplastophyte wall is also formed of phenolic compounds.
It is within Phragmoplastophyta we find the three clades of charophyte/streptophyte algae with true multicellular organization with differentiated cell types; Charophyceae, Coleochaetophyceae and land plants. The other charophyte algae are either unicellular, colonial, sarcinoid (three-dimensional packets of cells) or unbranched filamentous.
Below is a consensus reconstruction of green algal relationships, mainly based on molecular data.
References
Green algae | Phragmoplastophyta | [
"Biology"
] | 371 | [
"Algae",
"Green algae"
] |
58,032,665 | https://en.wikipedia.org/wiki/Edward%20Norman%20Dancer | Edward Norman Dancer FAA (born 29 December 1946, Bundaberg, Queensland, Australia) is an Australian mathematician, specializing in nonlinear analysis.
Dancer received in 1969 a Bachelor of Science with Honours (BSc (Hons)) from the Australian National University and in 1972 a PhD from the University of Cambridge with thesis advisor Frank Smithies and thesis Bifurcation in Banach Spaces. As a postdoc Dancer was from 1971 to 1972 at the University of Newcastle-upon-Tyne, UK and from 1972 to 1973 at the Institute of Advanced Studies at the Australian National University. At the University of New England in New South Wales, he was from 1973 to 1975 a lecturer, from 1976 to 1981 a senior lecturer, from 1981 to 1987 an associate professor, and from 1987 to 1993 a full professor. From 1993 to the present, he has been a full professor and chair of the school of mathematics and statistics at the University of Sydney.
Dancer is also a part time professor at Swansea University.
Honours and awards
1996 — elected a Fellow of the Australian Academy of Science (FAA)
2002 — Humboldt Research Award received from the Humboldt Foundation and Helmholtz Association
2009 — Hannan Medal awarded by the Australian Academy of Science
2010 — Invited Speaker at the International Congress of Mathematicians in Hyderabad
2017 — Schauder Medal
Selected publications
with Ralph S. Phillips:
with Peter Hess:
with Shusen Yan:
with Yihong Du:
with Juncheng Wei and Tobias Weth:
with Kelei Wang and Zhitao Zhang:
References
20th-century Australian mathematicians
21st-century Australian mathematicians
Fellows of the Australian Academy of Science
Mathematical analysts
Dynamical systems theorists
Australian National University alumni
Alumni of the University of Cambridge
Academic staff of the University of New England (Australia)
Academic staff of the University of Sydney
1946 births
Living people | Edward Norman Dancer | [
"Mathematics"
] | 359 | [
"Mathematical analysis",
"Dynamical systems theorists",
"Mathematical analysts",
"Dynamical systems"
] |
58,032,760 | https://en.wikipedia.org/wiki/An%20Astronomer | An Astronomer is an oil-on-canvas painting created in 1652 by Dutch artist Ferdinand Bol. He served as an apprentice to Rembrandt and earlier to Jacob Cuyp. The painting is held in the National Gallery, in London, to which it was donated by E.A. Bennett in 1862.
Description
The painting shows an astronomer at a table, on which are terrestrial and celestial globes. The work also draws on the themes of Melencolia I, an engraving by Albrecht Dürer.
The depicted man, who is peering into an open book with a frowning expression, can easily be identified as an astronomer due to the presence of a world map and a celestial sphere on the table. The painting perhaps belongs to the trend dating back to Dürer, in which scientists were depicted in the melancholy generated by the awareness of the futility of their research in face of the prospect of death.
References
Works about astronomy
1652 paintings
Paintings by Ferdinand Bol
Portraits of men
Paintings in the National Gallery, London
Oil on canvas paintings | An Astronomer | [
"Astronomy"
] | 209 | [
"Works about astronomy"
] |
58,033,746 | https://en.wikipedia.org/wiki/Tetramethylammonium%20fluoride | Tetramethylammonium fluoride, commonly abbreviated TMAF, is the quaternary ammonium salt with the formula (CH3)4NF. This hygroscopic white solid is a source of “naked fluoride": fluoride ions not complexed with a metal atom. Most other soluble salts of fluoride are in fact bifluorides, HF2–. Historically, there have been two main approaches to prepare tetramethylammonium fluoride: hydrofluoric acid neutralization of tetramethylammonium hydroxide, and salt metathesis between different ammonium salts and inorganic fluoride sources, such as KF or CsF. Because the fluoride anion is extremely basic, the salt slowly reacts with acetonitrile, inducing dimerization to CH3C(NH2)=CHCN, which co-crystallizes.
Related salts
Tetramethylphosphonium fluoride (CH3)4PF forms stable acetonitrile solutions. It is prepared from the ylide and potassium bifluoride:
(CH3)3P=CH2 + KHF2 → (CH3)4PF + KF
Gaseous tetramethylphosphonium fluoride exists as the phosphorane but autoionizes in acetonitrile solution. A more elaborate phosphazenium salt ([(CH3)2N)3P]2N+F−) is also known.
Anhydrous Tetrabutylammonium fluoride has been prepared by the reaction of hexafluorobenzene and tetrabutylammonium cyanide.
References
Tetramethylammonium salts
Fluorides
Nonmetal halides
Reagents for organic chemistry | Tetramethylammonium fluoride | [
"Chemistry"
] | 387 | [
"Reagents for organic chemistry",
"Fluorides",
"Salts"
] |
58,034,602 | https://en.wikipedia.org/wiki/Dihydrotestosterone%20undecanoate | Dihydrotestosterone undecanoate (DHTU), also known as androstanolone undecanoate or stanolone undecanoate, is a synthetic androgen and anabolic steroid (AAS) which was never marketed. It is an androgen ester; specifically, it is the C17β undecanoate (undecylate) ester of dihydrotestosterone (DHT). DHTU is a prodrug of DHT. Similarly to testosterone undecanoate (TU), DHTU is orally active. It occurs as an important active metabolite of oral TU. The 5α-reductase inhibitor finasteride in combination with oral TU has no effect on the first-pass transformation of TU into DHTU or DHT, probably because of its unique lymphatic route of absorption. Oral DHTU may be absorbed by the lymphatic system similarly to TU, and this may explain its oral bioavailability.
See also
List of androgen esters § Dihydrotestosterone esters
3α-Hydroxysteroid dehydrogenase
References
Abandoned drugs
Anabolic–androgenic steroids
Androstanes
Dihydrotestosterone esters
Human drug metabolites
Ketones
Undecanoate esters | Dihydrotestosterone undecanoate | [
"Chemistry"
] | 282 | [
"Ketones",
"Functional groups",
"Drug safety",
"Human drug metabolites",
"Chemicals in medicine",
"Abandoned drugs"
] |
58,034,672 | https://en.wikipedia.org/wiki/NGC%203867 | NGC 3867 is a spiral galaxy located about 350 million light-years away in the constellation Leo. It was discovered by French astronomer Édouard Stephan on 23 March 1884, and is a member of the Leo Cluster.
See also
List of NGC objects (3001–4000)
References
External links
3867
036649
+03-30-103
Leo (constellation)
Leo Cluster
Astronomical objects discovered in 1884
Spiral galaxies
06731
Discoveries by Édouard Stephan | NGC 3867 | [
"Astronomy"
] | 92 | [
"Leo (constellation)",
"Constellations"
] |
58,034,735 | https://en.wikipedia.org/wiki/CLUPI | CLUPI (Close-Up Imager) is a miniaturized camera system on board the planned European Space Agency Rosalind Franklin rover. CLUPI has been designed to acquire high-resolution close-up images in colour of soils, outcrops, rocks, drill fines and drill core samples, as well as and the search for potential biosignature structures and patterns. This camera assembly is part of the science payload on board the rover, tasked to search for biosignatures and biomarkers on Mars. It is planned to be launched not earlier than 2028 and land on Mars in 2029.
Overview
The CLUPI instrument is being developed by a Swiss–French consortium supported by the Swiss Space Office and the French Space Agency (CNES). Its Principal Investigator is Jean-Luc Josset, from the Space Exploration Institute, Neuchatel in Switzerland. Frances Westall and Beda Hofmann are Co-PIs. The science team includes scientists from Canada, Europe and Russia, especially for biosignature recognition. Instrument field tests started in 2009 with preliminary CLUPI systems tested during several Arctic winters.
CLUPI will be mounted on the movable rover's drill box and it will acquire high-resolution, close-up images in colour of the texture, structure and morphology of rocks and soil. The resolution will be similar to what geologists would obtain by using a hand-held magnifying lens: at a distance of 10 cm from the target, the maximum resolution is 7 μm/pixel. Its field of view can be changed by the use of two fixed, flat mirrors (FOV2 and FOV3). The CLUPI visual images will complement those provided by PanCam to provide the context necessary for interpretation of mineralogy and potential visible biosignatures.
CLUPI will observe the drilling area very closely from different angles to help characterise rock structures such as embedded crystals and fractures. After the drill has been used and retracted, CLUPI will be used to image the amount and appearance of dislodged fines. From the high position, the camera will be able to observe the borehole to a depth of approximately 10 cm, depending on the local illumination conditions. Then, CLUPI will be used to image the collected core prior to delivery to the rovers' internal analytical instruments for further processing and analyses.
See also
Astrobiology
Life on Mars
Planetary habitability
References
ExoMars
Mars imagers
Astrobiology | CLUPI | [
"Astronomy",
"Biology"
] | 508 | [
"Origin of life",
"Speculative evolution",
"Astrobiology",
"Biological hypotheses",
"Astronomical sub-disciplines"
] |
58,035,132 | https://en.wikipedia.org/wiki/Benty%20Grange%20hanging%20bowl | The Benty Grange hanging bowl is a fragmentary Anglo-Saxon artefact from the seventh century AD. All that remains are parts of two escutcheons: bronze frames that are usually circular and elaborately decorated, and that sit along the outside of the rim or at the interior base of a hanging bowl. A third one disintegrated soon after excavation, and it no longer survives. The escutcheons were found in 1848 by the antiquary Thomas Bateman, while excavating a tumulus at the Benty Grange farm in western Derbyshire. They were presumably buried as part of an entire hanging bowl. The grave had probably been looted by the time of Bateman's excavation, but still contained high-status objects suggestive of a richly furnished burial, including the hanging bowl and the boar-crested Benty Grange helmet.
The surviving escutcheons are made of enamelled bronze and are in diameter. They show three dolphin-like creatures arranged in a circle, each biting the tail of the one ahead of it. Their bodies and the background are made of enamel, likely all yellow; the creatures' outlines and eyes are tinned or silvered, as are the borders of the escutcheons. Although three escutcheons from a hanging bowl at Faversham also contain dolphin-like creatures, the Benty Grange design is most closely paralleled by Insular manuscripts, particularly figures in the Durham Gospel Fragment and the Book of Durrow. Surviving illustrations of the third escutcheon show that it was of a different size and style, exhibiting a scroll-like pattern. It parallels the basal disc of a hanging bowl from Winchester and may have been originally placed at the bottom of the Benty Grange bowl.
What remains of one escutcheon belongs to Museums Sheffield and as of 2023 was in the collection of the Weston Park Museum. The other is held by the Ashmolean Museum at the University of Oxford; as of 2023, it was not on display.
Hanging bowls
Hanging bowls are thin-walled bronze vessels with three or four equidistant hooks around the rim for suspension. They are a fixture of Late Celtic, Anglo-Saxon, and Viking archaeology and art, spanning approximately 400 AD to 1100 AD. The hooks project from escutcheons: bronze plates or frames that are usually circular or oval, that are frequently elaborately decorated, and that are riveted or soldered (or occasionally both) to the bowl. Basal escutcheons, also known as basal discs, would sometimes sit at the base of the interior. A 2005 catalogue of hanging bowls identified approximately 174 known examples, around 68 of which were relatively complete. England accounted for 117, Scotland for 7, and Ireland for 17, Norway for 26, and the remainder of Europe for 7.
The purpose of hanging bowls, and their places of manufacture, is unknown. They appear to have been manufactured by Celtic makers in Britain in the post-Roman period; examples were also used by Anglo-Saxons (who likely received bowls via trade) and, later, by Vikings. One possibility is that they were originally made by populations outside the sphere of Anglo-Saxon control, such as in the Severn Valley in southwest England and the Moray Firth in Scotland, and—as the Anglo-Saxon kingdoms extended their territories—were manufactured in progressively northern places, such as Dál Riata, Strathclyde, and Pictland, with the tradition ultimately taking root in Ireland also.
Many suggestions have been made regarding the original use of hanging bowls, including their use as lamps or lamp reflectors, votive vessels hung in churches, vessels for liturgical use such as washing hands or communion vessels, sanctuary lamps, wayside drinking vessels of the sort Edwin of Northumbria is said to have provided for travellers, finger bowls, scale pans for weighing wool, magnetic compasses, food containers, holy water stoups, wash basins, and ceremonial vessels used in mead halls. When they were acquired by Anglo-Saxons and Vikings, the bowls likely took on even more uses. Whatever their original functional purpose, by the seventh century, hanging bowls appear to have been increasingly associated with wealth and the status of their owners; during the seventh and early eighth centuries hanging bowls were a common feature in richly furnished Anglo-Saxon graves. By this point, the role of hanging bowls as a status symbol may have been more important than any functional purpose.
Description
Two escutcheons are all that remain of the Benty Grange hanging bowl. They are made of enamelled bronze and are in diameter. They have the same design and plain frames, parts of which survive. Both escutcheons are fragmentary; enough survives of each for the design to be reconstructed, and, because of overlapping segments, for it to be certain that they represent two distinct pieces. Whether they are hook or basal escutcheons is uncertain, but a contemporary watercolour by Llewellynn Jewitt suggests that a hook was present at excavation, and an iron ring, 2 millimetres in width and 16 in diameter, stuck to the back of one fragment may have been part of a suspension chain. The decomposed enamel background appears uniformly yellow to the eye, as it did when excavated. A yellow-creatures-on-red-background colour scheme has alternatively been claimed, but no evidence for such a layout has been presented. As sampling of the enamel was not permitted when one of the escutcheons was analysed in 1968, the all-yellow hypothesis is not definitive.
The reconstructed design shows three ribbon-style creatures resembling dolphins or fish, depicted in and arranged in a circle with each biting the tail of the one in front. The bodies are defined by their outlines. They are limbless, the tails curled in a circle, the jaws long and curved, and slightly ajar; the bitten tails pass under each creature's upper jaw and over its lower, but are missing where one would expect to see them passing through the gap between jaws. Each creature has a small eye shaped like a pointed oval. The outer borders of the discs, the plain frames, and the contours and eyes of the creatures are all tinned or silvered.
Surviving records of the third escutcheon indicate that it was of a different style and size. Drawings by Bateman and Jewitt show it with a scroll pattern and small piece of frame. It appears to have been about half the size of the other two, and may have originally been placed at the bottom of the hanging bowl.
The escutcheons were presumably part of an entire hanging bowl when buried. Nothing else survives. A mass of corroded chainwork discovered away, which survives only in illustrations by Jewitt and descriptions by Bateman, is unlikely to be related; although a large and intricate chain was found with a cauldron from Sutton Hoo, the Benty Grange chains appear dissimilar. The Benty Grange chainwork was also probably too heavy to have been used to suspend the hanging bowl.
Parallels
The dolphin-like designs on the Benty Grange hanging bowl are paralleled by designs on other escutcheons, and even more closely by designs on medieval illuminated manuscripts. Three escutcheons from a hanging bowl found in Faversham show creatures that also look like dolphins, but with more detailed bodies; a better parallel is with a disc found near the Lullingstone hanging bowl which dates to the late seventh century and is also decorated with dolphin-like creatures. Two other sixth- or seventh-century discs, found in Chilton and Coltishall, also depict intertwined serpent-like creatures attempting to eat their own tails. The third escutcheon from Benty Grange, meanwhile, surviving only in illustration, is most closely paralleled by the basal disc of the Winchester hanging bowl.
Even closer parallels to the Benty Grange designs are found in manuscript illustrations. Bateman remarked on this as early as 1861, noting that similar patterns were used in "several manuscripts of the [seventh] Century, for the purpose of decorating the initial letters". Metalwork designs like those on the Benty Grange escutcheons may have inspired aspects of the manuscript art. In particular, the mid-seventh-century Durham Gospel Fragment contains two similar fish-like motifs contained within the lateral stroke of the INI monogram that introduces the Gospel of Mark. The Book of Durrow also contains an illustration of similarly linked yellow dolphin-like creatures.
Date
The Benty Grange hanging bowl is dated by most experts to the second half of the seventh century, based on its design and the associated finds from the barrow in which it was found. Given the presence of a helmet and cup with silver crosses, wrote Audrey Ozanne, "[t]he straightforward interpretation of this find would seem to be that it dates from a period subsequent to the official introduction of Christianity into Mercia in 655". The surviving escutcheons also suggest a date in the mid-seventh century, given their resemblance to the illustrations in the Durham Gospel Fragment and the Book of Durrow; the Winchester hanging bowl's basal disc, which the third Benty Grange escutcheon resembles, has traditionally been given the same date.
Discovery
Location
The hanging bowl was discovered in a barrow on the Benty Grange farm in Derbyshire, in what is now the Peak District National Park. Thomas Bateman, an archaeologist and antiquarian who led the excavation, described Benty Grange as "a high and bleak situation"; its barrow, which still survives, is prominently located by a major Roman road, now roughly parallel to the A515 in the area, possibly to display the burial to passing travellers. The barrow is one of several tumuli in the vicinity and may have also been designed to share the skyline with two other nearby monuments, Arbor Low stone circle and Gib Hill barrow.
The seventh-century Peak District was a small buffer province between Mercia and Northumbria, occupied, according to the Tribal Hidage, by the Anglo-Saxon Pecsæte. The area came under the control of the Mercian kingdom around the eighth century; the Benty Grange and other rich barrows suggest that the Pecsæte may have had their own dynasty beforehand, but there is no written evidence for this.
Excavation
Bateman excavated the barrow on 3 May 1848. Although he did not mention it in his account, he was probably not the first person to dig up the grave. The fact that the objects were found in two clusters apart, and that other objects that normally accompany a helmet, such as a sword and shield, were absent, suggests that the grave had previously been looted. Given the size of the mound, an alternative (or additional) explanation is that it originally contained two burials, only one of which Bateman discovered.
The barrow comprises a circular central mound approximately in diameter and high, an encircling fosse about wide and deep, and outer penannular earthworks around wide and high. The entire structure measures approximately . Bateman suggested a body once lay at its centre, flat against the original surface of the soil; what he described as the one remnant, strands of hair, is now thought to be from a cloak of fur, cowhide or something similar. The recovered objects were found in two clusters. One cluster was found in the area of the supposed hair, the other about to the west. In the latter area Bateman described "a large mass of oxydized iron" which, when removed and washed, presented itself as a jumbled collection of chainwork, a six-pronged piece of iron resembling a hayfork, and the boar crested Benty Grange helmet.
In the area of the supposed hair, Bateman described "a curious assemblage of ornaments", which were difficult to remove successfully from the hardened earth. This included a cup identified as leather but probably of wood, approximately in diameter at the mouth. Its rim was edged with silver, and its surface was "decorated by four wheel-shaped ornaments and two crosses of thin silver, affixed by pins of the same metal, clenched inside". Also found were "a knot of very fine wire", some "thin bone variously ornamented with lozenges &c." attached to silk, but that soon decayed when exposed to air, and the Benty Grange hanging bowl. As Bateman described it
Bateman closed his 1848 account of the excavation by noting the "particularly corrosive nature of the soil", which by 1861 he said "has generally been the case in tumuli in Derbyshire". He suggested that this was the result of "a mixing or tempering with some corrosive liquid; the result of which is the presence of thin ochrey veins in the earth, and the decomposition of nearly the whole of the human remains." Bateman's friend Llewellynn Jewitt, an artist and antiquarian who frequently accompanied Bateman on excavations, painted four watercolours of the finds, parts of which were included in Bateman's 1848 account. This was more than Jewitt produced for any other of their excavations, a mark of the importance that they assigned to the Benty Grange barrow.
The hanging bowl escutcheons entered Bateman's extensive collection. On 27 October 1848 he reported his discoveries, including the helmet, cup, and hanging bowl, at a meeting of the British Archaeological Association, and in 1855 they were catalogued along with other objects from the Benty Grange barrow. In 1861 Bateman died at age 39, and in 1876 his son, Thomas W. Bateman, loaned the collection to the town council (the Corporation of Sheffield). It was displayed at the Weston Park Museum through 1893, at which point the younger Bateman, having spent his father's fortune, was forced to sell by order of chancery. The Corporation of Sheffield purchased many of the objects that had been excavated in Yorkshire, Derbyshire, and Staffordshire, including the helmet, the cup fittings, and one of the hanging bowl escutcheons; other pieces were dispersed by Sotheby's, and later in 1893 the second escutcheon was presented to the Ashmolean Museum at the University of Oxford by Sir John Evans. As of 2021 and 2023, respectively, the escutcheons remain in the collections of the two museums.
The Benty Grange barrow was designated a scheduled monument on 23 October 1970. The list entry notes that "[a]lthough the centre of Benty Grange [barrow] has been partially disturbed by excavation, the monument is otherwise undisturbed and retains significant archaeological remains." It goes on to note that further excavation would yield new information. The surrounding fields were designated a Site of Special Scientific Interest in 2013, and are used for agricultural purposes. The nearby farmhouse was renovated between 2012 and 2014; and as of 2023 is used as a holiday cottage.
Publication
Bateman published an article on the Benty Grange excavation in October 1848, five months after excavating the barrow, in The Journal of the British Archaeological Association. The finds were included in his 1855 catalogue of his collection, and shortly before his death, Bateman revised and expanded upon his 1848 account in his 1861 book Ten Years' Digging in Celtic and Saxon Grave Hills. Llewellynn Jewitt commented upon the finds, including the hanging bowl, in his 1870 book Grave-Mounds and their Contents.
The hanging bowl was one of the first to be discovered, and in 1898 John Romilly Allen included it among 16 examples in the first English article to discuss hanging bowls as a distinct class of artefacts. It was frequently mentioned in the literature thereafter, including reconstructions by T. D. Kendrick in 1932 and 1938, Françoise Henry in 1936, Audrey Ozanne in 1962–1963, George Speake in 1980, and Jane Brenan in 1991. Rupert Bruce-Mitford published a chapter on the Benty Grange burial in 1974, focusing on the helmet, and published what he termed a definitive reconstruction of the escutcheons in 1987; in his posthumous 2005 work A Corpus of Late Celtic Hanging-Bowls he added a full description of the hanging bowl, and a colour reconstruction of the escutcheons.
Notes
References
Bibliography
Henry's original drawing available at
Republished as an ebook as
7th-century artifacts
1848 archaeological discoveries
Anglo-Saxon archaeology
Anglo-Saxon art
Bronzeware
History of Derbyshire
Vitreous enamel | Benty Grange hanging bowl | [
"Chemistry"
] | 3,354 | [
"Coatings",
"Vitreous enamel"
] |
58,035,350 | https://en.wikipedia.org/wiki/Hunger%20stone | A hunger stone (German: Hungerstein) is a type of hydrological landmark common in Central Europe. Hunger stones serve as famine memorials and warnings and were erected in Germany and in ethnic German settlements throughout Europe in the 15th through 19th centuries.
These stones were embedded into a river during droughts to mark the water level as a warning to future generations that they will have to endure famine-related hardships if the water sinks to this level again. One famous example in the Elbe river in Děčín, Czech Republic, has "Wenn du mich siehst, dann weine" ("If you see me, weep") carved into it as a warning.
Many of these stones, featuring carvings or other artwork, were erected following the hunger crisis of 1816–1817 caused by the eruptions of the Tambora volcano.
In 1918, a hunger stone on the bed of the Elbe River, near Děčín, became exposed during a period of low water coincident with the wartime famines of World War I. Similar hunger stones in the river were uncovered again during droughts in 2018 and in 2022.
Known hunger stones
Common years
See also
Nilometer
References
Cultural history of Germany
Droughts in Europe
Famines in Europe
Stones | Hunger stone | [
"Physics"
] | 253 | [
"Stones",
"Physical objects",
"Matter"
] |
58,035,890 | https://en.wikipedia.org/wiki/Department%20of%20Energy%20%28Brunei%29 | The Department of Energy (), previously known as the Ministry of Energy and Ministry of Energy, Manpower and Industry, is a cabinet-level ministry in the Government of Brunei which oversees the country's energy industry. The department is led by the incumbent Deputy Minister of Energy, Mohammad Azmi bin Mohd Hanifah. The ministry is headquartered in the capital Bandar Seri Begawan, currently within the Prime Minister's Office building at Jalan Perdana Menteri.
History
The history of the ministry began in 2005 with the establishment of the Energy Division, then under the Prime Minister's Office. In May 2011, the Energy Department was established with the restructuring of the Energy Division and the then Petroleum Unit, and in October 2015 it was renamed the Energy and Industry Department after the transfer of oversight on the industry sector from the then Ministry of Industry and Primary Resources (now Ministry of Primary Resources and Tourism). The department was still under the Prime Minister's Office until 2018 when it was upgraded to a ministry by the consent of His Majesty Sultan Hassanal Bolkiah, the Sultan of Brunei, on 18 April in that year, and subsequently adopted the name Ministry of Energy and Industry. The ministry was restructured on 31 July in the same year, hence renamed the Ministry of Energy, Manpower and Industry. It was restructured again and finally adopted its current name on 18 November 2019, whereby the non-energy industry portfolio is now subsumed under the restructured Ministry of Finance and Economy, whereas the manpower portfolio is now the responsibility of the Manpower and Employment Council.
Budget
In the current fiscal year (2019–20), the ministry is allocated a budget of B$178.3 million (US$131 million as of July 2019).
List of ministers
Minister
Deputy minister
References
External links
Official website of the Department of Energy
Government agencies established in 2005
2005 establishments in Brunei
Energy | Department of Energy (Brunei) | [
"Engineering"
] | 381 | [
"Energy organizations",
"Energy ministries"
] |
58,035,891 | https://en.wikipedia.org/wiki/Bioinformatics%20discovery%20of%20non-coding%20RNAs | Non-coding RNAs have been discovered using both experimental and bioinformatic approaches. Bioinformatic approaches can be divided into three main categories. The first involves homology search, although these techniques are by definition unable to find new classes of ncRNAs. The second category includes algorithms designed to discover specific types of ncRNAs that have similar properties. Finally, some discovery methods are based on very general properties of RNA, and are thus able to discover entirely new kinds of ncRNAs.
Discovery by homology search
Homology search refers to the process of searching a sequence database for RNAs that are similar to already known RNA sequences. Any algorithm that is designed for homology search of nucleic acid sequences can be used, e.g., BLAST. However, such algorithms typically are not as sensitive or accurate as algorithms specifically designed for RNA.
Of particular importance for RNA is its conservation of a secondary structure, which can be modeled to achieve additional accuracy in searches. For example, Covariance models can be viewed as an extension to a profile hidden Markov model that also reflects conserved secondary structure. Covariance models are implemented in the Infernal software package.
Discovery of specific types of ncRNAs
Some types of RNAs have shared properties that algorithms can exploit. For example, tRNAscan-SE is specialized to finding tRNAs. The heart of this program is a tRNA homology search based on covariance models, but other tRNA-specific search programs are used to accelerate searches.
The properties of snoRNAs have enabled the development of programs to detect new examples of snoRNAs, including those that might be only distantly related to previously known examples. Computer programs implementing such approaches include snoscan and snoReport.
Similarly, several algorithms have been developed to detect microRNAs. Examples include miRNAFold and miRNAminer.
Discovery by general properties
Some properties are shared by multiple unrelated classes of ncRNA, and these properties can be targeted to discover new classes. Chief among them is the conservation of an RNA secondary structure. To measure conservation of secondary structure, it is necessary to somehow find homologous sequences that might exhibit a common structure. Strategies to do this have included the use of BLAST between two sequences or multiple sequences, exploited synteny via orthologous genes or used locality sensitive hashing in combination with sequence and structural features.
Mutations that change the nucleotide sequence, but preserve secondary structure are called covariation, and can provide evidence of conservation. Other statistics and probabilistic models can be used to measure such conservation. The first ncRNA discovery method to use structural conservation was QRNA, which compared the probabilities of an alignment of two sequences based on either an RNA model or a model in which only the primary sequence conserved. Work in this direction has allowed for more than two sequences and included phylogenetic models, e.g., with EvoFold. An approach taken in RNAz involved computing statistics on an input multiple-sequence alignment. Some of these statistics relate to structural conservation, while others measure general properties of the alignment that could affect the expected ranges of the structural statistics. These statistics were combined using a support vector machine.
Other properties include the appearance of a promoter to transcribe the RNA. ncRNAs are also often followed by a Rho-independent transcription terminator.
Using a combination of these approaches, multiple studies have enumerated candidate RNAs, e.g.,
Some studies have proceeded to manual analysis of the predictions to find a details structural and functional prediction.
See also
6A RNA motif
AbiF RNA motif
ARRPOF RNA motif
CyVA-1 RNA motif
List of RNA structure prediction software
References
Non-coding RNA
Bioinformatics | Bioinformatics discovery of non-coding RNAs | [
"Engineering",
"Biology"
] | 762 | [
"Bioinformatics",
"Biological engineering"
] |
58,036,017 | https://en.wikipedia.org/wiki/Veiling%20glare | Veiling glare is an imperfection of performance in optical instruments (such as cameras and telescopes) arising from incoming light that strays from the normal image-forming paths, and reaches the focal plane. The effect superimposes a form of noise onto the normal image sensed by the detector (film, digital sensor, or eye viewing through an eyepiece), resulting in a final image degraded by loss of contrast and reduced definition.
Scenes
In scenes where a bright object is next to a faint object, veiling glare from the bright object may hide the faint object from view, even though the instrument is otherwise capable of spatially resolving the two. Veiling glare is a limiting factor in high-dynamic-range imaging.
Glare in optical instruments differs from glare in vision, even though they both follow the same physical principles, because the phenomenon arises from mechanical versus physiological features.
Factors and design techniques
Light strays or scatters in lenses due to many potential factors in design and operation. These factors include dirt, film, or scratches on lens surfaces; reflections from lens surfaces or their mounts; and the slightly imperfect transparency (or reflection) of real glass (or mirrors).
Typical optical engineering design techniques to minimize stray light include: black coatings on internal surfaces, knife edges on mounts, antireflection lens coatings, internal baffles and stops, and tube extensions which block sources outside the field of view.
Veiling glare is a performance factor tested by UL standard 2802, Testing and Certification for the Performance of Video Cameras.
References
Optical metrology
Photometry
Geometrical optics
Geometric centers
Science of photography | Veiling glare | [
"Physics",
"Mathematics"
] | 326 | [
"Point (geometry)",
"Geometric centers",
"Symmetry"
] |
58,036,325 | https://en.wikipedia.org/wiki/Silicic%20acid | In chemistry, a silicic acid () is any chemical compound containing the element silicon attached to oxide () and hydroxyl () groups, with the general formula or, equivalently, . Orthosilicic acid is a representative example. Silicic acids are rarely observed in isolation, but are thought to exist in aqueous solutions, including seawater, and play a role in biomineralization. They are typically colorless weak acids that are sparingly soluble in water. Like the silicate anions, which are their better known conjugate bases, silicic acids are proposed to be oligomeric or polymeric. No simple silicic acid has ever been identified, since these species are primarily of theoretical interest.
Depending on the number of silicon atoms present, there are mono- and polysilicic (di-, tri-, tetrasilicic, etc.) acids. Well defined silicic acids have not been obtained in a form that has been characterized by X-ray crystallography.
Examples
Reactions
Silicic acids can be seen as hydrated forms of silica, namely . Indeed, in concentrated solutions, silicic acids generally polymerize and condense, and ultimately degrade to silicon dioxide and water. The intermediate stages may be very thick liquids or gel-like solids. Dehydrating the latter yields a hard translucent form of silica with atomic-scale pores, called silica gel, which is widely used as water absorbent and drying agent.
Silica dissolves very sparingly in water and is present in seawater at concentrations below 100 parts per million. In such dilute solutions, silica is assumed to exist as orthosilicic acid. Theoretical computations indicate that the dissolution of silica in water proceeds through the formation of a complex and then orthosilicic acid.
The silicon–oxygen double bond of metasilicic acid, implied by the formula , is hypothetical or highly unstable. Such double bonds can be hydrated to a pair of hydroxyl () groups:
=Si=O + H2O <-> =Si(-OH)2
For example,
\overset{metasilicic\ acid}{H2SiO3} + H2O <-> \overset{orthosilicic\ acid}{H4SiO4}
or
\overset{disilicic\ acid}{H2Si2O5} + 2 H2O <-> \overset{pyrosilicic\ acid}{(HO)3Si-O-Si(OH)3}
Alternatively, metasilicic acid is liable to form cyclic polymers , which can be opened by hydration to chain polymers . Similarly, disilicic acid is liable to form complex polymers with a tetravalent unit, . Conversely, oligomeric and polymeric acids may depolymerize by hydrolysis of the bridges, or such bridges may be created by condensation:
#Si-O-Si# + H2O <-> #Si-OH + HO-Si#
Like organic silanols, silicic acids are weak acids. Orthosilicic acid has calculated dissociation potentials pK = 9.84, pK = 13.2 at 25 °C.
Silicic acids and silicates in solution react with molybdate anions, yielding yellow silicomolybdate complexes. This reaction has been used to titrate the content of silicon in water solutions and determine their nature. In a typical preparation, monomeric orthosilicic acid was found to react completely in 75 seconds, dimeric pyrosilicic acid in 10 minutes, and higher oligomers in considerably longer time. The reaction is not observed with colloidal silica.
The degree of polymerization of silicic acids in water solution can be determined by its effect on the freezing point of the solution (cryoscopy).
History
Silicic acid was invoked by Jöns Jacob Berzelius in the early 19th century to explain the dissolution of silicon dioxide (silica, quartz) in water, namely through the hydration reaction:
\overset{silica}{SiO2} + \overset{water}{H2O} <-> \overset{silicic\ acid}{H2SiO3}
Based on the vapor pressure curves for silica gel, Reinout Willem Van Bemmelen argued that no silica hydrates existed, only silica gel. On the other hand, Gustav Tschermak von Seysenegg believed that he had observed different silicic acids as decomposition products of natural silicate gels.
The first crystalline silicic acid was prepared from the phyllosilicate natrosilite () in 1924. More than 15 crystalline acids are known and comprise at least six modifications of . Some acids can adsorb and intercalate organic molecules, and therefore are interesting alternatives to silica.
Preparation
Crystalline silicic acids can be prepared by removing the sodium cations from solutions of sodium silicates with an ion-exchange resin, or by treating sodium silicates with concentrated sulfuric acid.
See also
Boric acid
References
Mineral acids
Silanols
Silicon compounds | Silicic acid | [
"Chemistry"
] | 1,104 | [
"Acids",
"Inorganic compounds",
"Mineral acids"
] |
58,036,872 | https://en.wikipedia.org/wiki/Contact%20activation%20system | In the contact activation system or CAS, three proteins in the blood, factor XII (FXII), prekallikrein (PK) and high molecular weight kininogen (HK), bind to a surface and cause blood coagulation and inflammation. FXII and PK are proteases and HK is a non-enzymatic co-factor. The CAS can activate the kinin–kallikrein system and blood coagulation through its ability to activate multiple downstream proteins. The CAS is initiated when FXII binds to a surface and reciprocal activation of FXII and PK occurs, forming FXIIa and PKa. FXIIa can initiate the coagulation cascade by cleaving and activating factor XI (FXI), which leads to formation of a blood clot. Additionally, the CAS can activate the kinin–kallikrein system when PKa cleaves HK to form cHK, releasing a peptide known as bradykinin (BK). BK and its derivatives bind to bradykinin receptors B1 and B2 to mediate inflammation.
Surfaces and activation
Artificial negatively charged substances that activate FXII include L-homocysteine, heparan sulfates, chondroitin sulfates, dermatan sulfate, uric acid crystals, lipoproteins, ferritin and porphyrins. However, the physiological substances or surfaces that activate FXII are still under debate. These may include proteins, such as gC1q-R, aggregated proteins, amyloid, collagen, nucleic acids, and polyphosphates. The ability of FXII to bind to negatively charged surfaces and activate coagulation forms the basis of the aPTT test, in which artificial materials act as a surface for contact activation. This test is used to measure the contact activation pathway (intrinsic pathway) and the common pathway of clotting. FXII is a zymogen, which means that it requires processing to attain its catalytic protease activity. Upon binding to surfaces, FXII alters in its conformation, giving it low-level protease activity. This change in conformation also promotes its cleavage by PKa and cleavage by FXIIa itself. FXIIa can cleave PK producing PKa, producing a positive feed-back to activate both enzymes. HK binds to PK and is required to locate PK at the surface for activation by FXII.
Zinc has been reportedly demonstrated to be crucial in inducing a conformational change in both FXII and HK as it is required for assembly of FXII and HK bound PK on some negatively charged surfaces. Zinc is suggested to mediate binding of FXII and HK to negatively charged surfaces including gC1q-R and Polyphosphates.
Contact factors binding to bacteria and viruses
Although contact factors FXII and HK bound PK have been reported to interact with endothelial cells (via gC1q-R), platelets (via Polyphosphate) and Leukocytes; bacteria (Streptococcus pyogenes, Salmonella, and Escherichia coli) and viruses (Hantavirus and Herpes simplex 1 virus) have also been demonstrated to bind to contact factors. Negatively charged lipopolysaccharide (LPS) or surface associated negatively charged teichoic acids from S. aureus and long chain Polyphosphate have all been shown to induce contact activation and bradykinin release thereby contributing to the host-defense reactions by activating the complement cascade.
Physiological roles
Although the contact system can activate FXI and the subsequent clotting cascade, and it is routinely observed to activate coagulation in the presence of medical devices, the actual role of the contact system in normal physiological coagulation remains contentious. This is primarily due to the fact that deficiencies in the contact system proteins FXII, PK and HK do not produce bleeding disorders.
The contact activation system's physiological role in the kinin-kallikrein system is more clear. Here, after activation of PK to PKa by FXIIa, PKa cleaves HK. This produces cleaved HK (cHK), releasing a small peptide known as bradykinin. This peptide binds to bradykinin receptor B2 and its derivative, Des-Arg9-bradykinin binds to bradykinin receptor B1. Upon ligand binding, these receptors mediate inflammatory responses.
Roles in disease
Activation of the CAS is associated with hereditary angioedema, a disorder characterised by episodes of swelling.
Genetic knockout studies in murine models of cardiovascular disease and genetic linkage studies in humans have implicated the contact factors in contributing to diverse cardiovascular disease processes including thrombosis and stroke.
References
Coagulation system
Blood
Protein methods | Contact activation system | [
"Chemistry",
"Biology"
] | 993 | [
"Biochemistry methods",
"Protein methods",
"Protein biochemistry"
] |
58,036,987 | https://en.wikipedia.org/wiki/Bahamas%20Plastic%20Movement | The Bahamas Plastic Movement is a nonprofit organization based out of Eleuthera in the Bahamas that focuses on reducing plastic pollution. The organization was founded in 2013 by Kristal Ambrose. The organization specializes in using youth to end plastic pollution. They are an active member of the Plastic Pollution Coalition.
In 2017, the Bahamas Plastic Movement helped create Jack Johnson's music video for "You Can't Control It," and the cover for his album All the Light Above It Too.
Plastic bag ban
In 2018 a youth delegation from the Bahamas Plastic Movement traveled to Nassau, Bahamas to meet with Romauld Ferreira, Minister of the Environment and Housing, to ban plastic bags in the Bahamas. The Bahamas Plastic Movement claimed that if plastic pollution on beaches increased that $8.5 million in tourism would be lost. Fereira and his cabinet have since approved plans to phase out plastic bags by 2020.
References
Non-profit organisations based in the Bahamas
Ocean pollution
Eleuthera
Organizations established in 2014
2014 establishments in the Bahamas | Bahamas Plastic Movement | [
"Chemistry",
"Environmental_science"
] | 204 | [
"Ocean pollution",
"Water pollution"
] |
58,037,043 | https://en.wikipedia.org/wiki/Wheeler%20Jump | The Wheeler Jump is a type of subroutine call methodology that was used on some early computers that lacked hardware support for saving the return address. The concept was developed by David Wheeler while working on the pioneering EDSAC machine in the 1950s. EDSAC had not been built with subroutines in mind, and lacked a suitable processor register or a hardware stack that might allow the return address to be easily stored.
Wheeler's solution was a particular way to write the subroutine code. To implement it, the last line of the subroutine was a "jump to this address" instruction, which would normally be followed by a memory location. In a Wheeler subroutine, this address was normally set to a dummy number, say 0.
To call the routine, the address of the caller would be placed in the accumulator and then the code would jump to the starting point of the routine. The first instructions in the routine would calculate the return address based on the value in the accumulator, typically the next memory location so an increment will suffice, and then write the result to the dummy address previously set aside. When the routine runs its course it naturally reaches the end of the routine which now says "jump to the return address".
As writing to memory is a slow process compared to register access, this methodology is not particularly fast. It also is not capable of expressing recursion. The addition of new registers for this sort of duty was a key design goal of EDSAC 2.
Example
This example demonstrates the technique using a pseudo-assembler language for a simple byte-oriented accumulator-based machine with a single register, A:
'prepare to call the subroutine
10 COPY PC TO A ' copy the program counter (10) into the accumulator
11 JUMP ' jump to...
12 70 ' ... location 70
... many more lines...
70 ADD CONST ' add the following value to the accumulator...
71 3 ' ... three locations past the original PC value
72 STORE ' store the value in the accumulator to...
73 91 ' ... the set-aside memory location
... lines that perform the actual subroutine...
90 JUMP ' return to...
91 0 ' ... which will be replaced by 13
When this code completes, the JUMP instruction in address 90 will naturally return to location 13, the next instruction after the subroutine.
References
History of computing in the United Kingdom
Subroutines | Wheeler Jump | [
"Technology"
] | 523 | [
"Computing stubs",
"History of computing",
"History of computing in the United Kingdom"
] |
58,037,076 | https://en.wikipedia.org/wiki/Kernel-phase | Kernel-phases are observable quantities used in high resolution astronomical imaging used for superresolution image creation. It can be seen as a generalization of closure phases for redundant arrays. For this reason, when the wavefront quality requirement are met, it is an alternative to aperture masking interferometry that can be executed without a mask while retaining phase error rejection properties. The observables are computed through linear algebra from the Fourier transform of direct images. They can then be used for statistical testing, model fitting, or image reconstruction.
Prerequisites
In order to extract kernel-phases from an image, some requirements must be met:
Images are nyquist-sampled (at least 2 pixels per resolution element ())
Images are taken in near monochromatic light
Exposure time is shorter than the timescale of aberrations
Strehl ratio is high (good adaptive optics)
Linearity of the pixel response (i.e. no saturation)
Deviations from these requirements are known to be acceptable, but lead to observational bias that should be corrected by the observation of calibrators.
Definition
The method relies on a discrete model of the instrument's pupil plane and the corresponding list of baselines to provide corresponding vectors of pupil plane errors and of image plane Fourier Phases. When the wavefront error in the pupil plane is small enough (i.e. when the Strehl ratio of the imaging system is sufficiently high), the complex amplitude associated to the instrumental phase in one point of the pupil , can be approximated by . This permits the expression of the pupil-plane phase aberrations to the image plane Fourier phase as a linear transformation described by the matrix :
Where is the theoretical Fourier phase vector of the object. In this formalism, singular value decomposition can be used to find a matrix satisfying . The rows of constitute a basis of the kernel of .
The vector is called the kernel-phase vector of observables. This equation can be used for model-fitting as it represents the interpretation of a sub-space of the Fourier phase that is immune to the instrumental phase errors to the first order.
Applications
The technique was first used in the re-analysis of archival images from the Hubble Space Telescope where it enabled the discovery of a number of brown dwarf in close binary systems.
The technique is used as an alternative to aperture masking interferometry, especially for fainter stars because it does not require the use of masks that typically block 90% of the light, and therefore allows higher throughput. It is also considered to be an alternative to coronagraphy for direct detection of exoplanets at very small separations (below ) where coronagraphs are limited by the wavefront errors of adaptive optics.
The same framework can be used for wavefront sensing. In the case of an asymmetric aperture, a pseudo-inverse of can be used to reconstruct the wavefront errors directly from the image.
A Python library called xara is available on GitHub and maintained by Frantz Martinache to facilitate the extraction and interpretation of kernel-phases.
The KERNEL project, has received funding from the European Research Council to explore the potential of these observables for a number of use-cases, including direct detection of exoplanets, image reconstruction, and image plane wavefront sensing for adaptive optics.
References
Astronomical imaging
Astronomical interferometers
Image processing
Signal processing | Kernel-phase | [
"Astronomy",
"Technology",
"Engineering"
] | 696 | [
"Telecommunications engineering",
"Computer engineering",
"Astronomical interferometers",
"Signal processing",
"Astronomical instruments"
] |
58,037,613 | https://en.wikipedia.org/wiki/Standard%20Uptake%20Fraction | The Standard Uptake Fraction (SUF) is the relative distribution of water uptake of a plant in a soil with a uniform water potential. The SUF gives the ratio coefficient to obtain the equivalent soil water potential sensed by the plant. It is one of the macroscopic parameter for the hydraulic properties of the root system.
= the radial flow entering each root segment (), and
= the actual transpiration ().
In order to get this parameter, the easiest way is to deal with Functional-Structural Plant Models. They will compute the radial water flow for each root segment and then divide the total by the actual transpiration.
MARSHAL is a set of online tools developed to visualise the root system and allows to look after the SUF.
Standard Uptake Density
The standard uptake density (SUD) () is the distribution of the water uptake flow rate in the soil where the water potential is uniform. In other words:
= the segment length ().
Standard Sink Fraction
The standard sink fraction (SSF) is very similar to the SUF, but instead of being a function of the root segment, it is related to the soil voxel. It is the normalised distribution of the sink term in a uniform water potential soil.
See also
Absorption of water
Root system equivalent conductance
Compensatory conductance
References
Soil
Water | Standard Uptake Fraction | [
"Environmental_science"
] | 272 | [
"Water",
"Hydrology"
] |
58,037,756 | https://en.wikipedia.org/wiki/Bi%20Bi%20Monajemeh%20Nishaburi | Bi Bi Monajemeh Nishaburi () also known as Monajemeh Nishaburi or Bichai Munachchima (12031280) was a Persian-Tajik poet, mathematician and astronomer. She is chiefly known for her astronomical works. She was born in Nishapur, now in modern Iran.
Biography
Bi Bi Monajemeh Nishaburi's father, Kamal ad-Din Semnani, was the chief of the Shafi'i group in Nishabur, and an astronomer working for Shah Muhammad II of Khwarazm. Monajemeh learned about astronomy from her father; their house was used as a meeting place for scholars, intellectuals and philosophers, which enabled Monajemeh to learn about mathematics and astronomy at a young age. Her mother was the granddaughter of Mohammad ebn-Yahya, a notable lawyer in Khorasan.
Contemporary commentaries refer to Monajemeh as a virtuous woman, with a deep knowledge of astrology and making calendars. Some of her poems are extant.
Monajemeh became famous for her knowledge of astronomy; due to her proficiency, she became known as Bibi.
Monajemeh's profession as astrologer can be deduced from her title , worked as an astronomer and a consultant for Shah Jalal ad-Din Mingburnu (until 1247) and Shah Kayqubad I, both of whom believed in the use of astrology when devising military tactics. Monajemeh was consulted before many of their battles. She is said to have been present during battles fought against the Mongols, and was famous for fighting; it is mentioned by contemporary historians that she was present beside the sultan on the battlefield. During the war between the Shamians and the Roman Seljuks, Bibi predicted that the sultan would win the war. After his victory, his belief in her abilities as an astrologer were such that he placed his robe over her.
At the height of Monajemeh's fame, Kamal al-Din Kamiyar (on behalf of the Seljuk sultan Ala-al-Din Kiqbad) went to the court of the Khwarizmshahs, and observed saw her proximity to the sultan. On returning home, he informed Alaad-Din Kiqbad of her knowledge. However, by that time, Bibi's position at court had weakened. When the sultan was defeated by the Mongols and killed—an event she is said to have predicted—she moved to Damascus, where the Seljugy king, Kayqubad I, who had heard about Monajemeh, sent his representative to invite Monajemeh to his court. Monajemeh's successes raised her status at the court.
Monajemeh married Majd ad-Din Mohammad, an official in the court of Jalal ad-Din Mingburnu, who had previously been an official under Šams-al-Dīn Moḥammad, grandfather of the Persian statesman Shams al-din Muhammad ibn Muhammad Juvayni. The couple lived together as members of the royal household. Their son, Amir Naser ad-Din Hossein (also known as Naser ad-Din, as well as Ibn Bibi, because of his mother's fame), became a military commander, who wrote the history of the Seljuq dynasty from 1209 to 1300.
Safi-ad-din Ardabili was called Bibi Fatima.
Bi Bi Monajemeh Nishaburi died in Konya, now in Turkey.
Notes
References
Sources
Further reading
Ebn Bībī, Nāṣer-Al-Dīn Ḥosayn (Encyclopædia iranica)
ابن بی بی. «اخبار سلاجقة روم»، چاپ محمدجواد مشکور، تهران 1350 ش
حمدالله بن ابی بکر حمدالله مستوفی تاریخ گزیده چاپ عبدالحسین نوائی تهران 1362 ش
بهناز هاشمی پور: «بی بی منجمه»، بنیاد دایرالمعارف اسلامی. جلد5 ، چاپ دانشنامه جهان اسلام، تهران 1379 ش
عبدالرفیع حقیقت: تاریخ سمنان. انتشارات فرمانداری کل سمنان. سمنان 1352 ش
غلامحسین مصاحب: دایر المعارف فارسی، جلد1، چاپ دوم، انتشارات امیرکبیر، تهران 1380 ش
گی لسترنج جغرافیای تاریخی سرزمینهای خلافت شرقی ترجمة محمود عرفان تهران 1364 ش
13th-century Iranian mathematicians
13th-century Iranian astronomers
Astronomers of the medieval Islamic world
Women astronomers
1203 births
1280 deaths | Bi Bi Monajemeh Nishaburi | [
"Astronomy"
] | 1,170 | [
"Women astronomers",
"Astronomers"
] |
58,037,802 | https://en.wikipedia.org/wiki/Compensatory%20conductance | The compensatory root water uptake conductance (Kcomp) () characterizes how a plant compensates its water uptake under heterogeneous water potential.
It controls the root water uptake in a soil where the water potential is not uniform.
See also
Standard Uptake Fraction
Hydraulic conductivity
References
Plant physiology | Compensatory conductance | [
"Biology"
] | 68 | [
"Plant physiology",
"Plants"
] |
58,037,845 | https://en.wikipedia.org/wiki/Andreas%20Seeger | Andreas Seeger is a mathematician who works in the field of harmonic analysis. He is a professor of mathematics at the University of Wisconsin–Madison. He received his PhD from Technische Universität Darmstadt in 1985 under the supervision of Walter Trebels.
He was elected a fellow of the American Mathematical Society in 2014 for his contributions to Fourier integral operators, local smoothing,
oscillatory integrals, and Fourier multipliers. In 2017, he was awarded the Humboldt Prize.
He was awarded a Simons Fellowship in 2019.
References
External links
Living people
Year of birth missing (living people)
Place of birth missing (living people)
Nationality missing
20th-century German mathematicians
21st-century German mathematicians
University of Wisconsin–Madison faculty
Technische Universität Darmstadt alumni
Fellows of the American Mathematical Society
Mathematical analysts | Andreas Seeger | [
"Mathematics"
] | 167 | [
"Mathematical analysis",
"Mathematical analysts"
] |
58,038,601 | https://en.wikipedia.org/wiki/Trestolone%20enanthate | Trestolone enanthate, also known as 7α-methyl-19-nortestosterone 17β-enanthate (MENT enanthate), is an androgen and anabolic steroid (AAS) and progestogen which was never marketed. It is an androgen ester; specifically, it is the C17β enanthate (heptanoate) ester of trestolone (7α-methylestr-4-en-17β-ol-3-one). Trestolone enanthate has low affinity for sex hormone-binding globulin (SHBG), similarly to testosterone enanthate.
See also
List of androgen esters § Esters of other synthetic AAS
References
Abandoned drugs
Androgen esters
Anabolic–androgenic steroids
Enanthate esters
Estranes
Ketones
Sex hormone esters and conjugates
Progestogens
Synthetic estrogens | Trestolone enanthate | [
"Chemistry"
] | 209 | [
"Ketones",
"Functional groups",
"Drug safety",
"Abandoned drugs"
] |
58,038,703 | https://en.wikipedia.org/wiki/Information-centric%20networking%20caching%20policies | In computing, cache algorithms (also frequently called cache replacement algorithms or cache replacement policies) are optimizing instructionsor algorithmsthat a computer program or a hardware-maintained structure can follow in order to manage a cache of information stored on the computer. When the cache is full, the algorithm must choose which items to discard to make room for the new ones. Due to the inherent caching capability of nodes in Information-centric networking ICN, the ICN can be viewed as a loosely connect network of caches, which has unique requirements of Caching policies. Unlike proxy servers, in Information-centric networking the cache is a network level solution. Therefore, it has rapidly changing cache states and higher request arrival rates; moreover, smaller cache sizes further impose different kind of requirements on the content eviction policies. In particular, eviction policies for Information-centric networking should be fast and lightweight. Various cache replication and eviction schemes for different Information-centric networking architectures and applications are proposed.
Policies
Time aware least recently used (TLRU)
The Time aware Least Recently Used (TLRU) is a variant of LRU designed for the situation where the stored contents in cache have a valid life time. The algorithm is suitable in network cache applications, such as information-centric networking (ICN), content delivery networks (CDNs) and distributed networks in general. TLRU introduces a new term: TTU (Time to Use). TTU is a time stamp of a content/page which stipulates the usability time for the content based on the locality of the content and the content publisher announcement. Owing to this locality based time stamp, TTU provides more control to the local administrator to regulate in network storage.
In the TLRU algorithm, when a piece of content arrives, a cache node calculates the local TTU value based on the TTU value assigned by the content publisher. The local TTU value is calculated by using a locally defined function. Once the local TTU value is calculated the replacement of content is performed on a subset of the total content stored in cache node. The TLRU ensures that less popular and small life content should be replaced with the incoming content.
Least frequent recently used (LFRU)
The Least Frequent Recently Used (LFRU) cache replacement scheme combines the benefits of LFU and LRU schemes. LFRU is suitable for 'in network' cache applications, such as ICN, CDNs and distributed networks in general. In LFRU, the cache is divided into two partitions called privileged and unprivileged partitions. The privileged partition can be defined as a protected partition. If content is highly popular, it is pushed into the privileged partition. Replacement of the privileged partition is done as follows: LFRU evicts content from the unprivileged partition, pushes content from privileged partition to unprivileged partition, and finally inserts new content into the privileged partition. In the above procedure the LRU is used for the privileged partition and an approximated LFU (ALFU) scheme is used for the unprivileged partition, hence the abbreviation LFRU.
The basic idea is to filter out the locally popular contents with ALFU scheme and push the popular contents to one of the privileged partition.
References
Computer networking
Content delivery networks
Distributed data storage systems
Online content distribution | Information-centric networking caching policies | [
"Technology",
"Engineering"
] | 694 | [
"Computer networking",
"Computer science",
"Computer engineering"
] |
58,039,179 | https://en.wikipedia.org/wiki/Aluthge%20transform | In mathematics and more precisely in functional analysis, the Aluthge transformation is an operation defined on the set of bounded operators of a Hilbert space. It was introduced by Ariyadasa Aluthge to study p-hyponormal linear operators.
Definition
Let be a Hilbert space and let be the algebra of linear operators from to . By the polar decomposition theorem, there exists a unique partial isometry such that and , where is the square root of the operator . If and is its polar decomposition, the Aluthge transform of is the operator defined as:
More generally, for any real number , the -Aluthge transformation is defined as
Example
For vectors , let denote the operator defined as
An elementary calculation shows that if , then
Notes
References
External links
Bilinear forms
Matrices
Topology | Aluthge transform | [
"Physics",
"Mathematics"
] | 160 | [
"Mathematical objects",
"Matrices (mathematics)",
"Topology",
"Space",
"Geometry",
"Spacetime"
] |
58,040,026 | https://en.wikipedia.org/wiki/NGC%203868 | NGC 3868 is a lenticular galaxy located about 300 million light-years away in the constellation Leo. NGC 3868 was discovered by astronomer Édouard Stephan on March 23, 1884. It is a member of the Leo Cluster.
See also
List of NGC objects (3001–4000)
References
External links
3868
036638
+03-30-104
Leo (constellation)
Leo Cluster
Astronomical objects discovered in 1884
Lenticular galaxies
Discoveries by Édouard Stephan | NGC 3868 | [
"Astronomy"
] | 94 | [
"Leo (constellation)",
"Constellations"
] |
58,041,212 | https://en.wikipedia.org/wiki/Xinjiang%20internment%20camps | The Xinjiang internment camps, officially called vocational education and training centers by the government of China, are internment camps operated by the government of Xinjiang and the Chinese Communist Party Provincial Standing Committee. Human Rights Watch says that they have been used to indoctrinate Uyghurs and other Muslims since 2017 as part of a "people's war on terror", a policy announced in 2014. Thirty-seven countries have expressed support for China's government for "counter-terrorism and deradicalization measures", including countries such as Russia, Saudi Arabia, Cuba, and Venezuela; meanwhile 22 or 43 countries, depending on source, have called on China to respect the human rights of the Uyghur community, including countries such as Canada, Germany, Turkey and Japan. Xinjiang internment camps have been described as "the most extreme example of China's inhumane policies against Uighurs". The camps have been criticized by the subcommittee of the Canadian House of Commons Standing Committee on Foreign Affairs and International Development for persecution of Uyghurs in China, including mistreatment, rape, torture, and genocide.
The camps were established in 2017 by the administration of CCP general secretary Xi Jinping. Between 2017 and 2021 operations were led by Chen Quanguo, who was formerly a CCP Politburo member and the committee secretary who led the region's party committee and government. The camps are reportedly operated outside the Chinese legal system; many Uyghurs have reportedly been interned without trial and no charges have been levied against them (held in administrative detention). Local authorities are reportedly holding hundreds of thousands of Uyghurs in these camps as well as members of other ethnic minority groups in China, for the stated purpose of countering extremism and terrorism and promoting social integration.
The internment of Uyghurs and other Turkic Muslims in the camps constitutes the largest-scale arbitrary detention of ethnic and religious minorities since World War II. , it was estimated that Chinese authorities may have detained up to 1.8 million people, mostly Uyghurs but also including Kazakhs, Kyrgyz and other ethnic Turkic Muslims, Christians, as well as some foreign citizens including Kazakhstanis, in these secretive internment camps located throughout the region. According to Adrian Zenz, a major researcher on the camps, the mass internments peaked in 2018 and abated somewhat since then, with officials shifting focus towards forced labor programs. Other human rights activists and US officials have also noted a shifting of individuals from the camps into the formal penal system.
In May 2018, Randall Schriver, US Assistant Secretary of Defense for Indo-Pacific Security Affairs, said that "at least a million but likely closer to three million citizens" were imprisoned in detention centers, which he described as "concentration camps". In August 2018, Gay McDougall, a US representative at the United Nations Committee on the Elimination of Racial Discrimination, said that the committee had received many credible reports that 1 million ethnic Uyghurs in China have been held in "re-education camps". There have been comparisons between the Xinjiang camps and the Chinese Cultural Revolution.
In 2019, at the United Nations, 54 countries, including China itself, rejected the allegations and supported the Chinese government's policies in Xinjiang. In another letter, 23 countries shared the concerns in the committee's reports and called on China to uphold human rights. In September 2020, the Australian Strategic Policy Institute (ASPI) reported in its Xinjiang Data Project that construction of camps continued despite government claims that their function was winding down. In October 2020, it was reported that the total number of countries that denounced China increased to 39, while the total number of countries that defended China decreased to 45. Sixteen countries that defended China in 2019 did not do so in 2020.
The Xinjiang Zhongtai Group is running some of the reeducation camps and uses reallocated workers in their facilities.
Background
Xinjiang conflict
Various Chinese dynasties have historically exerted various degrees of control and influence over parts of what is modern-day Xinjiang. The region came under complete Chinese rule as a result of the westward expansion of the Manchu-led Qing dynasty, which also conquered Tibet and Mongolia. This conquest, which marked the beginning of Xinjiang under Qing rule, ended circa 1758. While it was nominally declared to be a part of China's core territory, it was generally seen as a distant land unto its own by the imperial court; in 1758, it was designated a penal colony and a site of exile, and as a result, it was governed as a military protectorate, not integrated as a province.
After the 1928 assassination of Yang Zengxin, the governor of the semi-autonomous Kumul Khanate in east Xinjiang under the Republic of China, Jin Shuren succeeded Yang as governor of the Khanate. On the death of the Kamul Khan Maqsud Shah in 1930, Jin entirely abolished the Khanate and took control of the region as its warlord. In 1933, the breakaway First East Turkestan Republic was established in the Kumul Rebellion. In 1934, the First Turkestan Republic was conquered by warlord Sheng Shicai with the aid of the Soviet Union before Sheng reconciled with the Republic of China in 1942. In 1944, the Ili Rebellion led to the Second East Turkestan Republic with dependency on the Soviet Union for trade, arms, and "tacit consent" for its continued existence before being absorbed into the People's Republic of China in 1949.
From the 1950s to the 1970s, the government sponsored a mass migration of Han Chinese to the region, policies promoting Chinese cultural unity, and policies punishing certain expressions of Uyghur identity. During this time, militant Uyghur separatist organizations with potential support from the Soviet Union emerged, with the East Turkestan People's Party being the largest in 1968. During the 1970s, the Soviets supported the United Revolutionary Front of East Turkestan (URFET) to fight the Chinese.
In 1997, a police roundup and execution of 30 suspected separatists during Ramadan led to large demonstrations in February 1997 that resulted in the Ghulja incident, a People's Liberation Army (PLA) crackdown that led to at least nine deaths. The Ürümqi bus bombings later that month killed nine people and injured 68 with responsibility acknowledged by Uyghur exile groups. In March 1997, a bus bomb killed two people with responsibility claimed by Uyghur radicals and the Turkey-based Organisation for East Turkistan Freedom.
In July 2009, riots broke out in Xinjiang in response to a violent dispute between Uyghur and Han Chinese workers in a factory and they resulted in over 100 deaths. Following the riots, Uyghur radicals killed dozens of Chinese citizens in coordinated attacks from 2009 to 2016. These included the August 2009 syringe attacks, the 2011 bomb-and-knife attack in Hotan, the March 2014 knife attack in the Kunming railway station, the April 2014 bomb-and-knife attack in the Ürümqi railway station, and the May 2014 car-and-bomb attack in an Ürümqi street market. Several of the attacks were orchestrated by the Turkistan Islamic Party (formerly the East Turkestan Islamic Movement) which has been designated a terrorist organization by several countries including Russia, Turkey, the United Kingdom, and the United States (until 2020), in addition to the United Nations.
Strategic motivations
After initially denying the existence of the camps the Chinese government has maintained that its actions in Xinjiang are justifiable responses to the threats of extremism and terrorism.
As a region on the northwestern periphery of China which is inhabited by ethnic/linguistic/religious minorities, Xinjiang has been said (by Raffi Khatchadourian) to have "never seemed fully within the Communist Party's grasp". Part of Xinjiang was once seized by Czarist Russia and it was also independent for a short period of time. Traditionally, the government of the People's Republic of China has favored an assimilationist policy towards minorities and it has accelerated this policy by encouraging the mass immigration of Han Chinese into minority lands. After the collapse of its rival and neighbor the Soviet Union—another huge multi-national communist state with one dominant ethnicity—the Chinese Communist Party was "convinced that ethnic nationalism had helped tear the former superpower to pieces". In addition, terrorist attacks were committed by Uyghurs in 2009, 2013, and 2014.
Several additional potential motives for the increased repression in Xinjiang have been presented by scholars who have conducted research outside China. First, the repression may simply be the result of increased dissent within the region beginning in circa 2009; second, it may be due to changes in minority policy which promoted assimilation into Han culture; and third, the repression may primarily be spearheaded by Chen Quanguo himself, the result of his personally hardline attitude towards perceived acts of sedition.
China's government has used the terrorist attacks of 9/11 as a justification for its actions against the Uyghurs. It claims that its actions in Xinjiang are necessary because Xinjiang is another front in the "global war on terrorism". Specifically, they are trying to rid China of the Shanghai Cooperation Organization's three evils. The three evils are "transnational terrorism, separatism, and religious extremism," all three of which the CCP believes the Uyghurs possess. The true reason for the repression of the Uyghurs is quite convoluted but some argue that this is based on the CCP's desire to preserve China's identity and integrity, rather than its desire to condemn terrorism.
Additionally, some analysts have suggested that the CCP considers Xinjiang a key route in China's Belt and Road Initiative (BRI), however, it considers Xinjiang's local population a potential threat to the initiative's success, or it fears that opening Xinjiang up may also open it up to radicalizing influences from other states which are participating in the BRI. Sean Roberts of George Washington University said the CCP sees Uyghurs' attachment to their traditional lands as a risk to the BRI. Researcher Adrian Zenz has suggested that the initiative is an important reason for the Chinese government's control of Xinjiang.
In November 2020, when the US dropped the Turkistan Islamic Party from its terrorist list because it was no longer "in existence", the decision was lauded by some intelligence officials because it removed the pretext for the Chinese government's decision to wage "terrorism eradication" campaigns against the Uyghurs. However, Yue Gang, a military commentator in Beijing stated, "in the wake of the US decision on the ETIM, China might seek to increase its counterterrorism activities." The group continues to be designated as a terrorist group by the United Nations Security Council as well as by the governments of other countries.
Policies from 2009 to 2016
Both prior to and until shortly after the July 2009 Ürümqi riots, Wang Lequan was the Party Secretary for the Xinjiang region, effectively the highest subnational role; roughly equivalent to a governor in a Western province or state. Wang worked on modernization programs in Xinjiang, including industrialization, development of commerce, roads, railways, hydrocarbon development and pipelines with neighboring Kazakhstan to eastern China. Wang also constrained local culture and religion, replaced the Uyghur language with Standard Mandarin as the medium of education in primary schools, and penalized or banned among government workers (in a region in which the government was a very large employer), the wearing of beards and headscarves, religious fasting and praying while on the job. In the 1990s, many Uyghurs in parts of Xinjiang could not speak Mandarin Chinese.
In April 2010, after the Ürümqi riots, Zhang Chunxian replaced Wang Lequan as the Communist Party chief. Zhang Chunxian continued and strengthened Wang's repressive policies. In 2011, Zhang proposed "modern culture leads the development in Xinjiang" as his policy statement and started to implement his modern culture propaganda. In 2012, he first mentioned the phrase "de-extremification" () campaigns and started to educate "wild Imams" () and extremists ().
In 2013, the Belt and Road Initiative was announced, a massive trade project at the heart of which is Xinjiang. In 2014, Chinese authorities announced a "people's war on terror" and local government introduced new restrictions, including a ban on long beards and wearing the burqa in public. In 2014, the concept of "transformation through education" began to be used in contexts outside of Falun Gong through the systematic "de-extremification" campaigns. Under Zhang, the Communist Party launched its "Strike Hard Campaign against Violent Terrorism" in Xinjiang.
In August 2016, Chen Quanguo, a well-known hardline Communist Party secretary in Tibet, took charge of the Xinjiang autonomous region. Chen was branded as responsible for a major component of Tibet's "subjugation" by critics.
Following Chen's arrival, local authorities recruited over 90,000 police officers in 2016 and 2017 – twice as many as they recruited in the past seven years, and laid out as many as 7,300 heavily guarded check points in the region. The province has come to be known as one of the most heavily policed regions of the world. English-language news reports have labelled the current regime in Xinjiang as the most extensive police state in the world.
Antireligious campaigns
As a communist state, China does not have an official state religion, but its government recognizes five different religious denominations, namely Buddhism, Taoism, Islam, Catholicism, and Protestantism. In 2014, Western media outlets reported that it has conducted antireligious campaigns in order to promote atheism. According to The Washington Post, the CCP under Xi Jinping shifted its policies in favor of a so-called "Sinicization" of ethnic and religious minorities. The trend accelerated in 2018 when the State Ethnic Affairs Commission and the State Administration for Religious Affairs were placed under the control of the CCP's United Front Work Department.
Groups that are targeted for surveillance
Around 2015, according to Chinese Human Rights Defenders, a senior CCP official argued that "a third" of Xinjiang's Uyghurs were "polluted by religious extremist forces", and needed to be "educated and reformed through concentrated force".
At about the same time, the Chinese state-security apparatus was developing a "Integrated Joint Operations Platform" (IJOP) to analyze information which was collected from its surveillance data. According to an analysis of this software by Human Rights Watch, a member of a minority group might be assessed by the IJOP as falling under one of 36 "person types" that could lead to arrest and internment in a re-education camp. Some of these person types included:
people who do not use a mobile phone
people who use the back door instead of the front
people who consume an "unusual" amount of electricity
people who have an "abnormal" beard
people who socialize too little
people who maintain "complex" relationships
people who have a family member that exhibits some of these traits and so is "insufficiently loyal"
History
Beginning in 2017, local media outlets generally referred to the facilities as "counter-extremism training centers" () and "education and transformation training centers" (). Most of those facilities were converted from existing schools or other official buildings, although some of them were purpose-built.
The heavily policed region and thousands of check points assisted and accelerated the detention of locals in the camps. In 2017 the region constituted 21% of all arrests in China despite comprising less than 2% of the national population, eight times more than the previous year. The judicial and other government bureaus of many cities and counties started to release a series of procurement and construction bids for those planned camps and facilities. Increasingly, massive detention centers were built up throughout the region and are being used to hold hundreds of thousands of people targeted for their religious practices and ethnicity.
Victor Shih, a political economist at the University of California, San Diego, said in July 2019 the mass internments were unnecessary because "no active insurgencies" existed, only "isolated terrorist incidents". He suggested that because a great deal of money was spent setting up the camps, the money likely went to associates of the politicians who created them.
According to the Chinese ambassador to Australia Cheng Jingye in December 2019, all of the "trainees" in the centers have graduated and have gradually returned to their jobs or found new jobs with government assistance. Cheng also called reports that one million Uyghurs had been detained in Xinjiang "fake news" and that "what has been done in Xinjiang has no ... difference with what the other countries, including western countries, [do] to fight against terrorists."
During the COVID-19 pandemic in mainland China, there were no reports of cases of the coronavirus in Xinjiang prisons or of conditions in the internment camps. After program suspensions due to the 2019–20 coronavirus pandemic, Uyghur workers were reported to have been returned to other parts of Xinjiang and the rest of China to resume work beginning in March 2020. In September 2020, the Australian Strategic Policy Institute (ASPI) launched its Xinjiang Data Project, which reported that construction of camps continued despite claims that their function was winding down, with 380 camps and detention centers identified.
The Muslim-majority countries like the UAE, Saudi Arabia and Egypt were showing open support towards the Asian nation, stating that "China has the right to take anti‐terrorism and de‐extremism measures". The Arab nations were neglecting the human rights abuses to not ruin the economic ties they maintained with China, which is a crucial trading partner and investor for these countries. Moreover, the exiled Uyghur Muslims in these countries were regularly being detained and deported back to China.
According to the Associated Press, a young Chinese woman, Wu Huan was captured for eight days in a Chinese-run secret detention site in Dubai. She revealed that at least two other Uyghur prisoners were detained with her at a villa turned into jail. Critics have largely criticized the UAE for its supporting role in detaining as well as deporting the Uyghur Muslims and other Chinese political dissidents at the orders of the Chinese government.
Leaks and hacks
The New York Times leak
On 16 November 2019, The New York Times released an extensive leak of 400 pages of documents, sourced from a member of the Chinese government, in the hope that CCP General Secretary Xi Jinping would be held accountable for his actions. The New York Times stated that the leak suggests discontent inside the Communist Party relating to the crackdown in Xinjiang. The anonymous government official who leaked the documents did so with the intent that the disclosure "would prevent party leaders, including Mr. Xi, from escaping culpability for the mass detentions."
We must be as harsh as them and show absolutely no mercy. — Xi Jinping on the terror attacks in 2014, (translated from Mandarin Chinese)
One document was a manual aimed at communicating messages to Uyghur students who were returning home and would ask about their missing friends or relatives who had been interned in the camps. It said that government staff should acknowledge that the internees had not committed a crime and that "it is just that their thinking has been infected by unhealthy thoughts." Officials were directed to say that even grandparents and family members who seemed too old to carry out violence could not be spared.
The New York Times stated that speeches obtained show how Xi views risks to the party similar to the collapse of the Soviet Union, which The New York Times stated Xi "blamed on ideological laxity and spineless leadership." Concerned that violence in the Xinjiang region could damage social stability in the rest of China, Xi stated "social stability will suffer shocks, the general unity of people of every ethnicity will be damaged, and the broad outlook for reform, development and stability will be affected." Xi encouraged officials to study how the US responded following the September 11 attacks. Xi likened Islamic extremism alternately to a virus-like contagion and a dangerously addictive drug, and declared that addressing it would require "a period of painful, interventionary treatment."
The China Daily reported in 2018 that CCP official Wang Yongzhi was removed for "serious disciplinary violations". The New York Times obtained a copy of Wang's confession (which the report noted was likely signed under duress) and stated that The New York Times believed he was sacked for being too lenient on Uyghurs, for example his release of 7,000 detainees. Wang had told his superiors that he was concerned that the actions against the Uyghurs would breed discontent and thus result in greater violence in the future. The leaked documents stated, "he ignored the party central leadership's strategy for Xinjiang, and he went as far as brazen defiance. ... He refused, to round up everyone who should be rounded up". The article was discreetly shared on the Chinese platform Sina Weibo, where some netizens expressed sympathy for him. In 2017, there were more than 12,000 investigations into party members in Xinjiang for infractions or resistance in the "fight against separatism", which was more than 20 times the figure in the previous year.
ICIJ leak
On 24 November 2019, the International Consortium of Investigative Journalists (ICIJ) published the China Cables, consisting of six documents, an "operations manual" for running the camps and detailed use of predictive policing and artificial intelligence to target people and regulate life inside the camps.
Shortly after the publication of the China Cables, leaker Asiye Abdulaheb went on to provide Adrian Zenz with the "Karakax list", allegedly a Chinese government spreadsheet that tracks the rationale behind 311 of the internments at a "Vocational Training Internment Camp" in the seat of Karakax County in Xinjiang. The purpose of the list may have been to coordinate judgments on whether an individual should remain in internment; in some entries, the word "agree" was written beside a judgment. Records detail how subjects dress and pray, and how their relatives and acquaintances behave. One subject was interned because she wore a veil years ago; another was interned for clicking on a link to a foreign website; a third was interned for applying for a passport, despite posing "no practical risk" according to the spreadsheet. In general, the subjects on the Karakax list all have relatives living abroad, a category that reportedly leads to "almost certain internment". 149 subjects are documented as violating birth control policies. 116 of the subjects are listed without explanation as "untrustworthy"; for 88 of these, this "untrustworthy" label is the only reason listed for internment. Younger men, in particular, are often listed as "untrustworthy person born in a certain decade". 24 subjects are accused of formal crimes, including six terrorism-related allegations. Most of the subjects have been released, or scheduled for release, following the end of their one-year internment term; however, some of these are recommended for release into "industrial park employment", raising concerns about possible forced labor.
Xinjiang Police Files hack
The 'Xinjiang Police Files', a large body of police files derived from data found in a hack of a local computer server, was sent to the German anthropologist Adrian Zenz, who works for the Victims of Communism Memorial Foundation. Zenz has been sanctioned by the Chinese government since 2021. He has been instrumental in exposing the camp system in Xinjiang. The files and some English translations are partly accessible via their special homepage set up by this foundation or via the links to an academic repository in Zenz' article in the Journal of the European Association for Chinese Studies.
The data was evaluated by journalists from 14 media companies worldwide, including the British BBC, Le Monde in France and El País in Spain. In Germany, Bayerischer Rundfunk and Der Spiegel examined and researched the data.
According to the evaluation of a number of digital forensic scientists and other experts, the Xinjiang Police Files come from the computers of the Chinese authorities. It is the largest data leak on Chinese state-run re-education camps that has been made public outside of China to date.
In May 2022, the BBC published summaries of the Xinjiang Police Files. The Xinjiang Police Files were published during the first visit by a UN human rights commissioner to China in 14 years. By combining the photographs of some 5,000 Uyghurs contained in the data with other data in the hack, details of over 2,800 detentions emerged. Other documents in the leak included police protocols for running an internment camp.
Camp facilities
In urban areas, most of the camps are converted from existing vocational schools, CCP schools, ordinary schools or other official buildings, while in suburban or rural areas the majority of camps were specially built for the purposes of re-education. These camps are guarded by armed forces or special police and equipped with prison-like gates, surrounding walls, security fences, surveillance systems, watchtowers, guard rooms, and facilities for armed police.
While there is no public, verifiable data for the number of camps, there have been various attempts to document suspected camps based on satellite imagery and government documents. On 15 May 2017, Jamestown Foundation, a Washington, DC-based think tank, released a list of 73 government bids related to re-education facilities. On 1 November 2018, the Australian Strategic Policy Institute (ASPI) reported on suspected camps in 28 locations. On 29 November 2018, Reuters and Earthrise Media reported 39 suspected camps. The East Turkistan National Awakening Movement reported an even larger numbers of camps.
In a 2018 report from US government-funded Radio Free Asia, Awat County (Awati) was said to have three re-education camps. An RFA listener provided a copy of a "confidentiality agreement" requiring re-education camp detainees to not discuss the workings of the camps, and said local residents were instructed to tell members of re-education camp inspection teams visiting No. 2 Re-education Camp that there was only one camp in the county. The RFA listener also said the No. 2 Re-education Camp had transferred thousands of detainees and removed barbed wire from the perimeter of the camp walls.
Boarding schools for the children of detainees
The detention of Uyghurs and other ethnic minorities has allegedly left many children without their parents. The Chinese government has allegedly held these children at a variety of institutions and schools colloquially known as "boarding schools", although not all are residential institutions, that serve as de facto orphanages. In September 2018, the Associated Press reported that thousands of boarding schools were being built. According to the Chinese Department of Education children as young as eight are enrolled in these schools.
According to Adrian Zenz and BBC in 2019, children of detained parents in boarding schools were penalized for failing to speak Mandarin Chinese and prevented from exercising their religion. In a paper published in the Journal of Political Risk, Zenz calls the effort a "systematic campaign of social re-engineering and cultural genocide". Human Rights Watch said that the children detained at child welfare facilities and boarding schools were held without parental consent or access. In December 2019, The New York Times reported that approximately 497,000 elementary and junior high school students were enrolled in these boarding schools. They also reported that students are only allowed to see family members once every two weeks and that they were forbidden from speaking the Uyghur language.
Locations
Numerous locations have been identified as re-education camps. The Australian Strategic Policy Institute, whose funding is primarily from the Australian Government with overseas funding primarily from the US State Department and Department of Defense, had identified more than 380 "suspected detention facilities".
Camps in Akto County (Aktu, Aketao), Kizilsu Kyrgyz Autonomous Prefecture
Four detention centers in Aksu City (Akesu), Aksu Prefecture
Artux City Vocational Skills Education Training Service Center in Artux in Kizilsu Prefecture
Jiashi County Secondary Vocational School () in Payzawat County (Jiashi), Kashgar Prefecture
Three detention centers in Kalpin County (Kelpin, Keping), Aksu Prefecture
Eight vocational training centres in Lop County (Luopu), Hotan Prefecture
Lop County No. 4 Vocational Skills Education and Training Center
Maralbexi County (Bachu County) re-education camp in Kashgar Prefecture
Eight camps in Turfan Prefecture
No. 4 Training Center (on the road between Turpan and Toksun County)
Three re-education camps in Uqturpan County (Uchturpan, Wushi), Aksu Prefecture
Yutian county vocational training centre in Yutian County (Keriya), Hotan Prefecture, among the largest of the camps
Camp detainees
The mass internment of Uyghurs and other Turkic Muslims in the camps has become the largest-scale arbitrary detention of ethnic and religious minorities since World War II.
Many media outlets have reported that hundreds of thousands of Uyghurs, as well as Kazakhs, Kyrgyz and other ethnic minorities, are held in the camps. Radio Free Asia, a news service funded by the US government, estimated in January 2018 that 120,000 members of the Uyghurs were being held in political re-education camps in Kashgar prefecture alone at the time. In 2018, local government authorities in Qira County expected to have almost 12,000 detainees in vocational camps and detention centres and some projects related to the centres outstripped budgetary limits. Reports of Uyghurs living or studying abroad being detained upon return to Xinjiang are common, which is thought to be connected to the re-education camps. Many living abroad have gone for years without being able to contact their family members still in Xinjiang, who may be detainees.
Uyghur political figure Rebiya Kadeer, who has been in exile since 2005, has had as many as 30 relatives detained or disappeared, including her sisters, brothers, children, grandchildren, and siblings, according to Amnesty International. It is unclear when they were taken away. In February 2021, two of Kadeer's granddaughters appeared in a video on Twitter denying abuses and telling her not to be "fooled again by those bad foreigners".
On 13 July 2018, Sayragul Sauytbay, an ethnic Kazakh Chinese national and former employee of the Chinese state, appeared in a court in the city of Zharkent, Kazakhstan for being accused of illegally crossing the border between the two countries. During the trial she talked about her forced work at a re-education camp for 2,500 ethnic Kazakhs. Her lawyer argued that if she is extradited to China, she would face the death penalty for exposing re-education camps in Kazakh court. Her testimony for the re-education camps have become the focus of a court case in Kazakhstan, which is also testing the country's ties with Beijing. On 1 August 2018, Sauytbay was released with a six-month suspended sentence and directed to regularly check-in with police. She applied for asylum in Kazakhstan to avoid deportation to China. Kazakhstan refused her application. On 2 June 2019 she flew to Sweden where she was subsequently granted political asylum.
According to a Radio Free Asia interview with an officer at the Onsu County police station, as of August 2018, 30,000 persons, or about one in six Uyghurs in the county (approximately 16% of the overall population of the county), were detained in re-education camps.
Russian-American Gene Bunin created the Xinjiang Victims Database to collect public testimonies on people detained in the camps, and its content had been referenced in articles by Al Jazeera, RFA, Foreign Policy, the Uyghur Human Rights Project, Amnesty and Human Rights Watch. On 14 January 2023, the database included photos of Hong Kong actors Andy Lau and Chow Yun-fat in a list of police officers responsible for rounding up "thousands of documented victims", which aroused suspicion on Twitter about the database's authenticity.
Writing in the Journal of Political Risk in July 2019, independent researcher Adrian Zenz estimated an upper speculative limit to the number of people detained in Xinjiang re-education camps at 1.5 million. In November 2019, Adrian Zenz estimated that the number of internment camps in Xinjiang had surpassed 1,000. In November 2019, George Friedman estimated that 1 in 10 Uyghurs are being detained in re-education camps.
When the BBC was invited to the camps in June 2019, officials there told them the detainees were "almost criminals" who could choose "between a judicial hearing or education in the de-extremification facilities". The Globe and Mail reported in September 2019 that some Han Chinese and Christian Uyghurs in Xinjiang who had disputes with local authorities or expressed politically unwelcome thoughts had also been sent to the camps.
Anonymous drone footage posted on YouTube in September 2019 showed kneeling blindfolded inmates that an analyst at the Australian Strategic Policy Institute said may have been an inmate transfer at a train station near Korla and may have been from a re-education camp.
Anar Sabit, an ethnic Kazakh from Kuytun living in Canada who was imprisoned in 2017 after returning home following the death of her father, was detained for having gone abroad. She found other minorities were interned for offenses such as using forbidden technology (WhatsApp, a V.P.N.), travelling abroad, but that even a Uyghur working for the Communist party as a propagandist could be interned for the offense of having been booked in a hotel by an airline with others who were under suspicion.
According to an anonymous Uyghur local government employee quoted in an article by US government-sponsored Radio Free Asia, during Ramadan 2020 (23 April to 23 May), residents of Makit County (Maigaiti), Kashgar Prefecture were told they could face punishment for religious fasting including being sent to a re-education camp.
According to an official report by the Chinese government, 1.3 million people received "vocational training" sessions annually between 2014 and 2019.
Waterboarding, mass rape, and sexual abuse are reported to be among the forms of torture used as part of the indoctrination process at the camps.
Testimonies about treatment
Officially, the camps are known as Vocational Education and Training Centers, informally as "schools", and described by some officials as "hospitals" where inmates are treated for the "disease" of "extremist ideology". According to internment officials quoted in Xinjiang Daily, (a Communist Party-run newspaper) while "requirements for our students" are "strict ... we have a gentle attitude, and put our hearts into treating them". Being in one "is actually like staying at a boarding school." The newspaper quoted a former inmate as stating during his internment he had realized he had been "increasingly drifting away from 'home,'" under the influence of extremism. "With the government's help and education, I've returned. ... "our lives are improving every day. No matter who you are, first and foremost you are a Chinese citizen.'" Testimonies in non-Communist Party literature from freed inmates have been considerably different.
Kayrat Samarkand, a Kazakh citizen who migrated from Xinjiang, was detained in one of the internment camps in the region for three months for visiting neighboring Kazakhstan. On 15 February 2018, Kazakh Foreign Minister Kairat Abdrakhmanov sent a diplomatic note to the Chinese Foreign Ministry, the same day as Kayrat Samarkand was freed from custody. After his release, Samarkand said that he faced endless brainwashing and humiliation, and that he was forced to study communist propaganda for hours every day and chant slogans giving thanks and wishing for a long life to Xi Jinping.
Mihrigul Tursun, a Uyghur woman detained in China, after escaping one of these camps, talked of beatings and torture. After moving to Egypt, she traveled to China in 2015 to spend time with her family and was immediately detained and separated from her infant children. When Tursun was released three months later, one of the triplets had died and the other two had developed health problems. Tursun said the children had been operated on. She was arrested for the second time about two years later. Several months later, she was detained the third time and spent three months in a cramped prison cell with 60 other women, having to sleep in turns, use the toilet in front of security cameras and sing songs praising the Chinese Communist Party.
Tursun said she and other inmates were forced to take unknown medication, including pills that made them faint and a white liquid that caused bleeding in some women and loss of menstruation in others. Tursun said nine women from her cell died during her three months there. One day, Tursun recalled, she was led into a room and placed in a high chair, and her legs and arms were locked in place. "The authorities put a helmet-like thing on my head, and each time I was electrocuted, my whole body would shake violently and I would feel the pain in my veins," Tursun said in a statement read by a translator. "I don't remember the rest. White foam came out of my mouth, and I began to lose consciousness," Tursun said. "The last word I heard them saying is that you being an Uyghur is a crime." She was eventually released so that she could take her children to Egypt, but she was ordered to return to China. Once in Cairo, Tursun contacted U.S. authorities and, in September, went to the United States and settled in Virginia. China's Foreign Ministry Spokesperson Hua Chunying has stated that Tursun was taken into custody by police on "suspicion of inciting ethnic hatred and discrimination" for a period lasting 20 days, but denies that Tursun was detained in a re-education camp.
Former inmates say that they are required to learn to sing the national anthem of China and communist songs. Punishments, like being placed in handcuffs for hours, waterboarding, or being strapped to "tiger chair" (a metal contraption) for long periods of time, are allegedly used on those who fail to follow.
Anar Sabit, a cooperative inmate who had a relatively minor offense of foreign travel, described her confinement in the women's section as prison-like and marked by bureaucratic rigidity but said that she was not beaten or tortured . Before and after her internment, Sabit said that she experienced what Chinese sometimes call gui da qiang, or 'ghost walls' "that confuse and entrap travelers". After her release from internment, she said that she remains a "focus person" in her hometown of Kuytun where she lives with her uncle's family. She described the town as resembling an "open air prison" due to the careful monitoring by cameras, sensors, police, and the neighborhood residential committee, and that she feels shunned by almost all friends and family and worries that she will endanger anyone who helps her. After Sabit moved out of her uncle's house, Sabit lived in the dormitory of the neighborhood residential committee who she said threatened to return her to the internment camp for speaking out of turn.
According to detainees, they were also forced to drink alcohol and eat pork, which are forbidden in Islam. Some reportedly received unknown medicines while others attempted suicide. There have also been deaths reported due to unspecified causes. Detainees have alleged widespread sexual abuse, including forced abortions, forced use of contraceptive devices and compulsory sterilization. It has been reported that Han officials have been assigned to reside in the homes of Uyghurs who are in the camps. Rushan Abbas of the Campaign for Uyghurs argues that the actions of the Chinese government amount to genocide according to United Nations definitions which are laid out in the Genocide Convention.
According to Time, Sarsenbek Akaruli, 45, a veterinarian and trader from Ili, Xinjiang, was arrested in Xinjiang on 2 November 2017. As of November 2019, he is still in a detention camp. According to his wife Gulnur Kosdaulet, Akaruli was put in the camp after police found the banned messaging app WhatsApp on his cell phone. Kosdaulet, a citizen of neighboring Kazakhstan, has traveled to Xinjiang on four occasions to search for her husband but could not get help from friends in the Chinese Communist Party. Kosdaulet said of her friends, "Nobody wanted to risk being recorded on security cameras talking to me in case they ended up in the camps themselves."
In May to June 2017, a woman native to Maralbexi County (Bachu) named Mailikemu Maimati (also spelled Mamiti) was detained in the county's re-education camp according to her husband Mirza Imran Baig. He said that after her release, she and their young son were not given their passports by Chinese authorities.
According to Time, former prisoner Bakitali Nur, 47, native of Khorgos, Xinjiang on the Sino-Kazakh border, was arrested because authorities were suspicious of his frequent trips abroad. He reported spending a year in a cell with seven other prisoners. The prisoners sat on stools seventeen hours a day, were not allowed to talk or move and were under constant surveillance. Movement carried the punishment of being put into stress positions for hours. After release, he was forced to make daily self-criticisms, report on his plans and work for negligible payment in government factories. In May 2019, he escaped to Kazakhstan. Nur summarized his experience in jail and under constant monitoring after his release saying, "The entire system is designed to suppress us."
According to Radio Free Asia, Ghalipjan, a 35 year old Uyghur man from Shanshan/Pichan County who was married and had a five-year-old son, died in a re-education camp on 21 August 2018. Authorities reported his death was due to heart attack, but the head of the Ayagh neighborhood committee said that he was beaten to death by a police officer. His family was not allowed to carry out Islamic funeral rites.
According to the Xinjiang Police Files, Chen Quanguo issued a shooting order for detainees attempting to escape in 2018.
In June 2018, President of the World Uyghur Congress (WUC) Dolkun Isa was told that his mother Ayhan Memet, 78, had died two months earlier while in detention at a "political re-education camp". The WUC president was unsure if she had been incarcerated in one of the many "political re-education camps".
According to a 2018 report in The New York Times, Abdusalam Muhemet, 41, who ran a restaurant in Hotan before fleeing China in 2018, said he spent seven months in prison and more than two months in a camp in Hotan in 2015 without ever being criminally charged. Muhemet said that on most days, the inmates at the camp would assemble to hear long lectures by officials who warned them not to embrace Islamic radicalism, support Uyghur independence or defy the Communist Party.
In an interview with Radio Free Asia, an officer at the Kuqa (Kuchar, Kuche) County Police Department reported that from June to December 2018, 150 people at the No. 1 Internment Camp in the Yengisher district of Kuqa county had died, corroborating earlier reports attributed to Himit Qari, former area police chief.
In August 2020, the BBC released texts and a video smuggled out of a re-education camp by Merdan Ghappar, a former model of Uyghur heritage. Mergan had been allowed access to personal effects, and used a phone to take videos of the camp he is interned in.
In February 2021, the BBC issued further eyewitness accounts of mass rape and torture in the camps. Sayragul Sauytbay told the BBC as a teacher forced to work in the camps that "rape was common" and the guards "picked the girls and young women they wanted and took them away". She also described a woman who was brought to make a forced confession in front of 100 other detainees while the police took turns to rape her as she cried out for help. In 2018, a Globe and Mail interview with Sauytbay found that she did not personally see violence at the camp, but did witness hunger and a complete lack of freedom. Tursunay Ziawudun, a Uyghur who fled to Kazakhstan and then the US, told the BBC that she was raped three times in the camps and kicked in the abdomen during interrogations. In a 2020 interview with BuzzFeed News, Ziawudun reported that she "wasn't beaten or abused" while inside, but was instead subjected to long interrogations, forced to watch propaganda, kept in cold conditions with poor food, and had her hair cut.
Forced labor
Adrian Zenz reported that the re-education camps also function as forced labor camps in which Uyghurs and Kazakhs produce various products for export, especially those made from cotton grown in Xinjiang. The growing of cotton is central to the industry of the region as "43 percent of Xinjiang's exports are apparel, footwear, or textiles". In 2018, 84% of China's cotton was produced in the Xinjiang province. Since cotton is grown and processed into textiles in Xinjiang, a November 2019 article from The Diplomat said that "the risk of forced labor exists at multiple steps in the creation of a product".
Academics Zhun Xu and Fangfei Lin write that the conclusion of forced labor in cotton production in Xinjiang is insufficiently supported. They cite the historic significance of Uyghur agricultural workers as a long-standing labor force for manual cotton harvesting and staffing companies' widespread recruitment of Uyghur workers due to lower travel costs. In their view, "[T]he labor demand of Uyghur seasonal cotton pickers in south Xinjiang is largely decided by its relatively low degree of agricultural capitalization, not due to the 'special treatment' towards labor migrants of a certain ethnic minority."
In 2018, the Financial Times reported that the Yutian / Keriya county vocational training centre, among the largest of the Xinjiang re-education camps, had opened a forced labour facility including eight factories spanning shoemaking, mobile phone assembly and tea packaging, giving a base monthly salary of . Between 2016 and 2018, the centre expanded 269 percent in total area.
The Australian Strategic Policy Institute reported that from 2017 to 2019 more than 80,000 Uyghurs were shipped elsewhere in China for factory jobs that "strongly suggest forced labour". Conditions of these factories were consistent with the stipulations of forced labor as defined by the International Labour Organization.
In 2021, former supplier for Nike, Esquel Group, sued the United States Government for listing it on a sanction list for forced labor allegations in Xinjiang. It was later removed from the sanction list due to lack of evidence provided by the US Commerce department.
In October 2021, the CBC in collaboration with the Investigative Reporting Project Italy along with The Guardian reported on the export of tomato products from Xinjiang and tied to forced labor by the Uyghurs. The report identified tomato products being exported to other countries such as Italy to be repackaged for sale in other markets such as Canada.
In June 2021, human rights reports indicated that costs of solar modules had been depressed in recent years due to Chinese forced labor practices in the solar module and wind turbine exports industry. Globally, China dominated manufacturing, installation and exports in the field. The practice of forced labor was blamed for the bankruptcy of firms in the US and German solar industries, multiple times, over the decade 2010–2020. In one report, upon declaring a bankruptcy, the cost of raw materials for manufacturing panels was suggested to be 30% of the total manufacturing costs. It was argued that China do not pay labor costs.
Notable detainees
Ablajan Awut Ayup, rapper
Merdan Ghappar, model
Adil Mijit, comedian, suspected detainee
Mihrigul Tursun (former detainee)
Responses from China
Prior to October 2018, when international media had asked about the re-education camps, China's Ministry of Foreign Affairs said that they have not heard of this situation. The Chinese government officially legalized re-education camps in Xinjiang in October 2018.
On 12 August 2018, a Chinese state-run tabloid, Global Times, defended the crackdown in Xinjiang after a U.N. anti-discrimination committee raised concerns over China's treatment of Uyghurs. According to the Global Times, China prevented Xinjiang from becoming 'China's Syria' or 'China's Libya', and local authorities' policies saved countless lives and avoided a 'great tragedy'.
On 13 August 2018, at a UN meeting in Geneva, the delegation from China told the United Nations Human Rights Committee that "There is no such thing as re-education centers in Xinjiang and it is completely untrue that China put 1 million Uyghurs into re-education camps". A Chinese delegation said that "Xinjiang citizens, including the Uyghurs, enjoy equal freedom and rights." They said that "Some minor offenders of religious extremism or separatism have been taken to 'vocational education' and employment training centers with a view to assisting in their rehabilitation".
On 14 August 2018, Chinese Foreign Ministry spokesman Lu Kang said "anti-China forces had made false accusations against China for political purposes and a few foreign media outlets misrepresented the committee's discussions and were smearing China's anti-terror and crime-fighting measures in Xinjiang" after a UN human rights committee raised concern over reported mass detentions of ethnic Uyghurs.
On 21 August 2018, Liu Xiaoming, the Ambassador of China to the United Kingdom, wrote an article in response to a Financial Times report entitled "Crackdown in Xinjiang: Where have all the people gone?". Liu's response said: "The education and training measures taken by the local government of Xinjiang have not only effectively prevented the infiltration of religious extremism and helped those lost in extremist ideas to find their way back, but also provided them with employment training in order to build a better life."
On 10 September 2018, China's Foreign Ministry spokesperson Geng Shuang condemned a report about the re-education camps issued by Human Rights Watch. He said: "This organisation has always been full of prejudice and distorting facts about China." Geng also added that: "Xinjiang is enjoying overall social stability, sound economic development and harmonious co-existence of different ethnic groups. The series of measures implemented in Xinjiang are meant to improve stability, development, solidarity and people's livelihood, crack down on ethnic separatist activities and violent and terrorist crimes, safeguard national security, and protect people's life and property."
On 11 September 2018, China called for UN human rights chief Michelle Bachelet to "respect its sovereignty", after she urged China to allow monitors into Xinjiang and expressed concern about the situation there. Chinese Foreign Ministry spokesman Geng Shuang said: "China urges the U.N. human rights high commissioner and office to scrupulously abide by the mission and principles of the U.N. charter, respect China's sovereignty, fairly and objectively carry out its duties, and not listen to one-sided information".
On 16 October 2018, a CCTV prime-time program aired a 15-minute episode on what was termed as Xinjiang's 'Vocational Skills Educational Training Centers', featuring the Muslim internees. Sinologist Manya Koetse documented that it received a mixture of supportive and critical responses on the Sina Weibo social media platform.
In March 2019, against the background of the US considering imposing sanctions against Chen Quanguo, who is the region's most senior Communist Party official, Xinjiang governor Shohrat Zakir refuted international claims of concentration camps and re-education camps, instead comparing the institutions to boarding schools.
On 18 March 2019, the Chinese government released a white paper about counter-terrorism and de-radicalization in Xinjiang. The white paper states, "A country under the rule of law, China respects and protects human rights in accordance with the principles of its Constitution." The white paper also contends that Xinjiang has not had violent terrorist cases for more than two consecutive years, extremist penetration has been effectively curbed, and social security has improved significantly.
In November 2019, the Chinese ambassador to the United Kingdom responded to questions about newly leaked documents on Xinjiang by calling the documents "fake news".
On 6 December 2019, China's Foreign Ministry spokesperson Hua Chunying accused the US of hypocrisy on human rights issues relating to allegations of torture at Guantanamo Bay detention camp.
In September 2020, Xi Jinping acclaimed the success of his policies in Xinjiang in a 2-day conference expected to set the country's policy for the next years. The Chinese government published a white paper defending its vocational training centers and stating that the regional government organised 'employment-oriented training' and labour skills for 1.29 million workers a year from 2014 to 2019.
On 7 January 2021, the US Chinese embassy published a tweet that said: "The minds of (Uighur) women in Xinjiang were emancipated and gender equality and reproductive health were promoted, making them no longer baby-making machines," which drew sharp criticism from human rights groups as well as Sam Brownback, the US envoy on international religious freedom. Subsequently, the tweet was deleted and Twitter locked the embassy's account.
In March 2021, following sanctions imposed on several Chinese officials by the European Union, the United States, the United Kingdom and Canada, the Chinese government responded with sanctions on several individuals and groups that had criticized China over the camps, including five European Parliament members (among them Reinhard Butikofer, the head of the European Parliament's delegation to China), German scholar Adrian Zenz, and the non-profit Alliance of Democracies Foundation.
In June 2021, ProPublica and The New York Times documented a Chinese government-backed propaganda campaign on Twitter and YouTube involving more than 5000 videos analysed. They showed Uyghurs in Xinjiang denying abuses and scolding foreign officials and multinational corporations who had questioned China's human rights record in the province. Some of the videos' accounts were removed on YouTube as part of the company's efforts to combat spam and influence operations.
In October 2022, the Australian Strategic Policy Institute documented a number of CCP-backed Uyghur influencers in Xinjiang posting propaganda videos on Chinese and Western social media which pushed back against abuse allegations. Some of the influencers' accounts were suspended on Twitter for alleged inauthenticity.
International reactions
Reactions at the UN
On 8 July 2019, 22 countries issued a statement in which they called for an end to mass detentions in China and expressed their concerns about widespread surveillance and repression. 50 countries issued a counter-statement, reportedly coordinated by Algeria, criticizing the practice of "politicizing human rights issues", stating "China has invited a number of diplomats, international organizations officials and journalist to Xinjiang" and that "what they saw and heard in Xinjiang completely contradicted what was reported in the media." The counter-statement also commended China's "remarkable achievements in the field of human rights", claiming that "safety and security has returned to Xinjiang and the fundamental human rights of people of all ethnic groups there are safeguarded." Qatar formally withdrew its name from the counter-statement on 18 July, six days after it was published, expressing a desire "to maintain a neutral stance and we offer our mediation and facilitation services."
In October 2019, 23 countries issued a joint statement urging China to "uphold its national laws and international obligations and commitments to respect human rights, including freedom of religion or belief," urging China to refrain from "arbitrary detention of Uyghurs and members of other Muslim communities.
In response, on the same day, 54 countries (including China itself) issued a joint statement reiterating that the work of human rights in the United Nations should be conducted in a "non-politicized manner", and supporting China's Xinjiang policies. The statement spoke positively of the results of counter-terrorism and de-radicalization measures in Xinjiang and held that these measures have effectively safeguarded the basic human rights of people of all ethnic groups." Civil society groups in Muslim-majority countries with governments that have supported China's policies in Xinjiang have been noted to be uncomfortable with their governments' stance and have organized boycotts, protests, and media campaigns concerning Uyghurs.
In October 2020, Axios reported that more countries at the UN joined the condemnation of China over Xinjiang abuses. The total number of countries that denounced China increased to 39, while the total number of countries that defended China decreased to 45. Notably, 16 countries that defended China in 2019 did not do so in 2020.
At the 46th session of the Human Rights Council, Cuba delivered a joint statement supporting China, signed by 64 countries.
Reactions by international organizations
Governmental organizations
On 21 May 2018, during the resumed session of the Committee on Non-Governmental Organizations in the United Nations, Kelley Currie, the United States representative to the United Nations for economic and social affairs, raised the issue of mass detention of Uyghurs in re-education camps, and she said that "reports of mass incarcerations in the Xinjiang were documented by looking at Chinese procurement requests on Chinese websites requesting Chinese companies to tender offers to build political re-education camps".
On 10 August 2018, United Nations human rights experts expressed alarm over many credible reports that China had detained a million or more ethnic Uyghurs in Xinjiang. Gay McDougall, a member of the United Nations Committee on the Elimination of Racial Discrimination, said that "In the name of combating religious extremism, China had turned Xinjiang into something resembling a massive internment camp, shrouded in secrecy, a sort of no-rights zone".
On 10 September 2018, UN human rights chief Michelle Bachelet called on China to ease restrictions on her and her office's team, urging China to allow observers into Xinjiang and expressing concern about the situation there. She said, "The UN rights group had shown that Uyghurs and other Muslims are being detained in camps across Xinjiang and I expect discussions with Chinese officials to begin soon".
In June 2019, UN counter-terrorism chief Vladimir Voronkov visited Xinjiang and found nothing incriminating at the camps.
On 1 November 2019, ten UN Special Rapporteurs together with vice-chair of the UN Working Group on Arbitrary Detention and chair-rapporteur of the UN Working Group on Enforced or Involuntary Disappearances released a report on the effect and application of the Counter-Terrorism Law of China and its Regional Implementing Measures in Xinjiang, which states that:The De-Extremism Regulations have been criticised by UN Special Procedures mandates for their lack of compliance with international human rights standards. Following the introduction of those laws, an estimated million Uyghurs and other Turkic Muslims have reportedly been sent to internment facilities under the guise of "counterterrorism and de-extremism" policies since 2016. (p.4) ...... In this context, previous communications by the Special Rapporteur on freedom of religion or belief and the Working Group on Arbitrary Detention have voiced their concern that the "re-education facilities", sometimes termed "vocational training centres", due to their coercive character, amount to detention centres. It is alleged that between 1 million to 1.5 million ethnic Uyghurs and other minorities in Xinjiang may have been arbitrary forced into these facilities, where there have been allegations of deaths in custody, physical and psychological abuse and torture, as well as lack of access to medical care. It is also reported that in several cases they have been denied free contact with their families and friends or been unable to inform them of their location and denied their basic freedom of movement.(p.8)
In June 2020, nearly 50 UN independent experts had repeatedly communicated with the Government of the People's Republic of China their alarm regarding the repression of fundamental freedoms in China. They had also raised their concerns regarding a range of issues of grave concern, including the collective repression of the population, especially religious and ethnic minorities in Xinjiang and Tibet.
In March 2021, sixteen UN human right experts raised grave concerns about the "alleged detention and forced labour of Muslim Uyghurs in China". The experts were appointed by the UN Human Rights Council, and several of them said they had "received information that connected over 150 domestic Chinese and foreign domiciled companies to serious allegations of human rights abuses against Uyghur workers". The experts also called for unrestricted access to China in order to conduct "fact-finding missions", meanwhile urging "global and domestic companies to closely scrutinize their supply chains".
On 11 September 2018, Federica Mogherini, the High Representative of the European Union for Foreign Affairs and Security Policy, raised the re-education camps issue in European Parliament. She said:The most outstanding disagreement we have with China concerns the human rights situation in China, as underlined in your Report. We also focused on the situation in Xinjiang, especially the expansion of political re-education camps. And we discussed the detention of human rights defenders, including particular cases.
On 19 December 2019, the European Parliament passed a non-binding resolution condemning the mass incarceration of Uyghurs and calling on EU companies with supply chains in the region to ensure that they are not complicit with crimes against humanity.
On 17 December 2020, the European Parliament adopted a resolution that strongly condemns China over allegations of forced labor by ethnic and religious minorities. In the statement, the EU body said Parliament "strongly condemns the government-led system of forced labor, in particular the exploitation of Uyghur, ethnic Kazakh and Kyrgyz, and other Muslim minority groups, in factories both within and outside of internment camps in Xinjiang, as well as the transfer of forced laborers to other Chinese administrative divisions, and the fact that well-known European brands and companies have been benefiting from the use of forced labor."
On 22 March 2021, the European Union, joined by the United States, the United Kingdom and Canada, imposed sanctions on four senior Chinese officials and the Public Security Bureau of the Xinjiang Production and Construction Corps over the human rights abuses of Uyghurs in Xinjiang. This was the first sanction by the EU against China since the 1989 Tiananmen Square massacre.
World Bank
On 11 November 2019, the World Bank issued a statement: In line with standard practice, immediately after receiving a series of serious allegations in August 2019 in connection with the Xinjiang Technical and Vocational Education and Training Project, the Bank launched a fact-finding review, and World Bank senior managers traveled to Xinjiang to gather information directly. After receiving the allegations, no disbursements were made on the project. The team conducted a thorough review of project documents... The review did not substantiate the allegations. In light of the risks associated with the partner schools, which are widely dispersed and difficult to monitor, the scope and footprint of the project is being reduced. Specifically, the project component that involves the partner schools in Xinjiang is being closed.
Organization for Islamic Cooperation
On 1 March 2019, the OIC produced a document which "commends the efforts of the People's Republic of China in providing care to its Muslim citizens."
A coalition of American Muslim groups criticized the OIC's decision and accused member states of being influenced by Chinese power. The groups included the Council on American-Islamic Relations.
Human rights organisations
On 10 September 2017, Human Rights Watch released a report that said "The Chinese government should immediately free people held in unlawful 'political education' centers in Xinjiang and shut them down."
On 9 September 2018, Human Rights Watch released a 117-page report, "'Eradicating Ideological Viruses': China's Campaign of Repression Against Xinjiang's Muslims", which accused China of the systematic mass detention of tens of thousands of ethnic Uyghurs and other Muslims in political re-education camps without being charged or tried and presented new evidence of the Chinese government's mass arbitrary detention, torture, and mistreatment, and the increasingly pervasive controls on daily life. The report also urged foreign governments to pursue a range of multilateral and unilateral actions against China for its actions, including "targeted sanctions" against those responsible.
On 7 January 2020, CAIR National Executive Director Nihad Awad condemned a tweet by the US Chinese embassy, saying that China was openly admitting to and celebrating forced sterilizations and abortions of Muslim Uyghur women by saying it had "emancipated" them from being "baby-making machines".
Amnesty International published a dedicated website and an extensive report in 2021. Amnesty estimates up to 1 million prisoners and concludes "The evidence Amnesty International has gathered provides a factual basis for the conclusion that the Chinese government has committed at least the following crimes against humanity: imprisonment or other severe deprivation of physical liberty in violation of fundamental rules of international law; torture; and persecution." Their full report includes recommendations to the Chinese government, the UN and the international community in general.
Reactions by countries
In September 2019, Australian Foreign Minister Marise Payne stated, "I have previously raised Australia's concerns about reports of mass detentions of Uyghurs and other Muslim peoples in Xinjiang. We have consistently called for China to cease the arbitrary detention of Uyghurs and other Muslim groups. We have raised these concerns—and we will continue to raise them—both bilaterally and in relevant international meetings."
In January 2020, the Bahrain Council of Representatives called on the international community to protect Uyghur Muslims in China and "expressed deep concern over the inhumane and painful conditions to which Uyghur Muslims in China are subjected, including the detention of more than one million Muslims in mass detention camps, denial of their most basic rights, the removal of their children, wives and families, their prevention of prayer, worship and religious practices, confronting murder, ill-treatment and torture."
On 5 March 2021, a group of 65 member states—led by Belarus—expressed their support of China's Xinjiang policy and opposed the "unfounded allegations against China based on disinformation" at the 44th session of Human Rights Council.
On 15 March 2021, the Walloon Parliament voted to approve a motion condemning the "unacceptable" practices introduced by the Chinese government, including the exploitation of Uyghurs and all other ethnic minorities, in Xinjiang. All parties voted in favor, with the exception of the Workers' Party, which abstained.
On 22 February 2021, the Canadian House of Commons voted 266–0 to approve a motion that formally recognizes China is committing genocide against its Muslim minorities. Prime Minister Justin Trudeau and his cabinet did not vote.
On 6 October 2020, Cuba delivered a joint statement with 45 other countries voicing their support of China's measures in Xinjiang.
Egypt signed both statements at the UN (in July and October 2019) that supported China's Xinjiang policies. Egypt has been accused of deporting Uyghurs to China.
In November 2019, French Foreign Minister Jean-Yves Le Drian called on China to close down the camps. He also called on China to permit the UN High Commissioner for Human Rights to visit Xinjiang at the earliest possible date to make a report on the situation. The French Ministry of Europe and Foreign Affairs issued a statement on 27 November:
In December 2020, France said it will oppose the proposed Comprehensive Agreement on Investment between the European Union and China over the use of forced labour of Uyghurs.
In December 2018, leaders of the Muslim organization Muhammadiyah issued an open letter citing reports of violence against the "weak and innocent" community of Uyghurs and asking Beijing to explain. Soon after, Beijing responded by inviting more than a dozen top Indonesian religious leaders to the Xinjiang province and camps, and criticism greatly diminished. Since then, Indonesia's largest Muslim organizations have purportedly treated reports of widespread human rights violations in Xinjiang with skepticism, dismissing them as U.S. propaganda.
In October 2022, the Indonesian delegation for the UNHCR voted against debate in the chamber on the topic of the treatment of Uyghurs in Xinjiang as it "will not yield meaningful progress", but Ambassador Febrian Ruddyard also stated, "As the world's largest Muslim country and a vibrant democracy, we cannot close our eyes to the plight of our Muslim brothers and sisters."
In a December 2016 report, the research unit of the Iranian state-owned television's external services said that China is not opposed to Muslims, but instead to pro-Saudi radical ideology. In August 2020, Ali Motahari, a former member of the Iranian Parliament, tweeted that the Iranian government has kept silent about the situation of Muslims in China because the government of Iran needs China's economic support. He said that this silence has been humiliating for the Islamic Republic. Critics of Motahari responded that China was opposed to Wahabism, and had no problem with Islam or Chinese Muslims.
Iran signed an October 2019 letter that publicly expressed support for China's treatment of Uyghurs.
On 26 November 2019, Japanese Foreign Minister Toshimitsu Motegi said Japan was "monitoring the human rights situation in the Xinjiang Uygur Autonomous Region with concern" and that he brought up Japan's position with State Councilor Wang Yi in their meeting on 25 November.
In November 2017, Kazakhstan's Ambassador to China Shahrat Nuryshev met with Chinese Vice Minister of Foreign Affairs Li Huilai regarding Kazakh diaspora issues.
On 15 February 2018, Kazakh Foreign Minister Kairat Abdrakhmanov sent a diplomatic note to the Chinese Foreign Ministry, the same day Samarkand, a Kazakhstan citizen, was released from re-education camp. From 17 to 19 April, Kazakh First Deputy Foreign Minister Mukhtar Tleuberdi visited Xinjiang to meet with local officials.
On 20 May 2021, the Seimas passed a non-binding resolution condemning China's treatment of Uyghurs.
In September 2020, the Muhyiddin government confirmed that it would not extradite ethnic Uyghurs to China if Beijing requests it, continuing the policy set by the Mahathir administration. Although it is the government of Malaysia's stance not to get involved in Chinese internal affairs, it stated that the oppression of Uyghurs in the country could not be denied. Mohd Redzuan Md Yusof, minister in the Prime Minister's Department also stated that his government would grant free passage to those refugees who wished to settle in a third country.
On 25 February, the States General of the Netherlands declared China's treatment of the Uyghur ethnic minority a genocide, the third country to do so.
On 6 May 2021, the New Zealand Parliament passed a motion condemning China's treatment of the Uyghurs in Xinjiang, but fell short of calling it genocide, due to opposition from the governing Labour Party, who would not pass the motion unless the term 'genocide' was removed.
New Zealand Prime Minister Jacinda Ardern has raised the issue of the Uyghurs on numerous occasions, including in her 2019 meeting with CCP General Secretary Xi Jinping. She did not detail exactly what was said. In July 2019, New Zealand Foreign Minister Winston Peters, asked why New Zealand had signed the letter to the president of the United Nations Human Rights Council criticizing Beijing for its treatment of ethnic Uyghurs in the Xinjiang region stated, "Because we believe in human rights, we believe in freedom and we believe in the liberty of personal beliefs and the right to hold them."
In 2017, National MP Todd McClay represented his party in Beijing before a dialogue organised by the International Liaison Department of the Chinese Communist Party. McClay also referred to the Xinjiang internment camps as "vocational training centers" in line with CCP talking points.
Pakistan signed both statements at the UN (in July and October 2019) that supported China's Xinjiang policies.
On 19 January 2020, Pakistani Prime Minister Imran Khan was asked why he was not more outspoken about the situation of Uyghurs in China. He said that he has not been as outspoken primarily because the human rights situation in Kashmir and Citizenship Amendment Act were problems much larger in scale. He said that the second reason was that China has been a great friend of Pakistan and had helped Pakistan through their toughest time with the economic crisis, so that "the way we deal with China is that when we talk about things, we talk about privately. We do not talk about things with China in public right now because they are very sensitive. That's how they deal with issues."
In July 2020, Xi Jinping met with Palestinian President Mahmoud Abbas to express Beijing's "full support" for the two-state solution to the Israeli–Palestinian conflict, saying that "China and Palestine are good brothers, good friends and good partners". Abbas then voiced support for China's "legitimate position on Hong Kong, Xinjiang and other matters concerning China's core interests."
After Palestinian ambassador to China visited Xinjiang in March 2021, he remarked on Chinese state media that he was impressed by the region's infrastructure and upkeep of mosques, saying "if you have to calculate it all, it's something like 2,000 inhabitants for one mosque. This ratio, we don't have it in our country. It's not available anywhere." RFA journalist Shohret Hoshur wrote in response that Mehdawi was neglecting the harsh reality of locals with whom he had met and who had no ability to speak the truth under the watch of officials, adding that his true motivation seemed to be a shared anti-US agenda with China.
On 4 February 2019, Russian Foreign Minister Sergey Lavrov said he was not aware of reports about political re-education camps in China's Xinjiang Uygur Autonomous Region, though he had seen the US actively raising the issue.
In July 2019, Russia signed the letter supporting China at the UN Human Rights Council.
On 9 October 2019, Lavrov said that "China has repeatedly given explanations concerning the accusations that you have mentioned probably citing our Western colleagues. We have no reason to take any steps other than the procedures that exist at the UN that I mentioned, such as at the Human Rights Council and its Universal Periodic Reviews."
In February 2019, Saudi Arabia's Crown Prince Mohammad bin Salman defended China's use of the camps, saying "China has the right to carry out anti-terrorism and de-extremisation work for its national security."
Saudi Arabia was among the 24 countries (excluding China) that backed China's position at the UN Human Rights Council in July 2019, and again at the UN General Assembly in October 2020.
On 6 November 2018 during the UN Human Rights Council's Universal Periodic Review of China, Switzerland called on China to close down its detention camps in Xinjiang, to grant the UN High Commissioner for Human Rights unrestricted access to Xinjiang, and to allow an independent UN investigation of the detention camps.
On 26 November 2019, the Federal Department of Foreign Affairs called on the Chinese government to address the concerns raised by many states and to allow the UN unhindered access to the region.
In December 2019, the Syrian Ministry of Foreign Affairs and Expatriates defended China's actions in Xinjiang days after the US condemnation, stating that it is a "blatant interference by the US in the internal affairs of the People's Republic of China." The statement concluded that "Syria emphasizes the right of China to preserve its sovereignty, people, territorial integrity, and security and protect the security and property of the state and individuals."
On 2 October 2018 the Minister of Foreign Affairs, Joseph Wu, used the MOFA's official Twitter account to send out a Radio Free Asia article titled "Xinjiang Authorities Secretly Transferring Uyghur Detainees to Jails Throughout China" and stated that, "relocation of Uyghurs to re-education camps around China warrants the world's attention."
On 5 July 2019, Joseph Wu, again on Twitter, sent out a BBC News article titled "China Muslims: Xinjiang schools used to separate children from families" and called on China to "Close the camps! Send the children home!"
On 18 November 2019, the MOFA's official Twitter sent out a New York Times article titled "'Absolutely No Mercy': Leaked Files Expose How China Organized Mass Detentions of Muslims" saying, "This chilling NYTimes expose on the mass detention of Muslims by China is a must-read! Leaked internal documents tell the truth about the crackdown on ethnic minorities in Xinjiang, as well as the 'ruthless & extraordinary campaign' run by senior Communist Party officials."
In February 2019, after Turkish media had picked up rumors of Uyghur musician Abdurehim Heyit dying in detention, the Spokesperson for the Turkish Foreign Ministry denounced China for "violating the fundamental human rights of Uyghur Turks and other Muslim communities in the Xinjiang Uygur Autonomous Region." In July 2019, Turkish journalists from Milliyet and Aydınlık interviewed Heyit in Ürümqi who denied that Uyghurs had problems in China.
In July 2019, Chinese state media reported that when Turkish President Erdoğan visited China, he said, "It is a fact that the people of all ethnicities in Xinjiang are leading a happy life amid China's development and prosperity." Turkish officials then claimed the paraphrase was mistranslated by the Turkish side, saying it should rather have read "hopes the peoples of China's Xinjiang live happily in peace and prosperity". Erdoğan also said that some people were seeking to "abuse" the Xinjiang crisis to jeopardize the "Turkish–Chinese relationship". Some Uyghurs in Turkey have expressed concerns that they may face deportation back to China.
On 3 July 2018, at a U.K. Parliamentary roundtable, the Rights Practice helped to organize a Parliamentary Round-table on increased repression and forced assimilation in Xinjiang. Rahima Mahmut, an Uyghur singer and human rights activist, gave a personal testimony about the violations suffered by the Uyghur community. Dr. Adrian Zenz, European School of Culture and Theology, (Germany), outlined the evidence of a large scale and sophisticated political re-education network designed to detain people for long periods and which the Chinese government officially denies.
On 16 December 2020, the U.K. said there was credible, growing, and troubling evidence of forced labor among Uyghur Muslims in Xinjiang. Nigel Adams, Minister of State for Asia told Parliament, "Evidence of forced Uyghur labor within Xinjiang, and in other parts of China, is credible, it is growing and deeply troubling to the UK government." Adams said firms had a duty to ensure their supply chains were free of forced labor.
On 12 January 2021, the Foreign Secretary, Dominic Raab, announced if British businesses fail to ensure their supply chains are free of slave labour could face fines. Raab appeared to be targeting China's mistreatment of internees in Xinjiang, saying it was Britain's "moral duty" to respond to the "far-reaching" evidence of human rights abuses being perpetrated in Xinjiang.
On 23 April, a group of MPs led by Sir Iain Duncan Smith passed a motion declaring the mass detention of Uyghur Muslims in Xinjiang province a genocide. The United Kingdom is the fourth country in the world to make such action. In response, the Chinese Embassy in London said "The unwarranted accusation by a handful of British MPs that there is 'genocide' in Xinjiang is the most preposterous lie of the century..."
On 3 April 2018, U.S. Senator Marco Rubio and Representative Chris Smith sent a letter urging Ambassador to China Terry Branstad to launch an investigation into the reported mass detention of Uyghurs in political re-education camps in Xinjiang.
On 26 July 2018, Vice President of the United States Mike Pence raised the re-education camps issue at Ministerial to Advance Religious Freedom. He said that "Sadly, as we speak as well, Beijing is holding hundreds of thousands, and possibly millions, of Uyghur Muslims in so-called 're-education camps', where they're forced to endure around-the-clock political indoctrination and to denounce their religious beliefs and their cultural identity as the goal."
On 26 July 2018, the Congressional-Executive Commission on China, an independent agency of the U.S. government which monitors human rights and rule of law developments in the People's Republic of China, released a report that said as many as a million people are or have been detained in what are being called "political re-education" centers, the largest mass incarceration of an ethnic minority population in the world today. On 27 July 2018, The U.S. Embassy & Consulate in China released Ministerial to Advance Religious Freedom Statement on China, which mentioned the detention of hundreds of thousands, and possibly millions, of Uyghurs and members of other Muslim minority groups in "political re-education camps", and called the Chinese government to release immediately all those arbitrarily detained.
On 28 August 2018, U.S. senator Marco Rubio and 16 other members of Congress urged the United States to impose sanctions under the Global Magnitsky Human Rights Accountability Act against Chinese officials who are responsible for human rights abuses in Xinjiang. In a letter to Secretary of State Mike Pompeo and Treasury Secretary Steven Mnuchin, they called for the sanctions on Chen Quanguo who is the current Communist Party Secretary of the Xinjiang (the highest post in an administrative unit of China) and six other Chinese officials and two businesses that make surveillance equipment in Xinjiang.
U.S. Secretary of State Mike Pompeo criticized Iran's Supreme Leader Ayatollah Ali Khamenei for his refusal to condemn the Chinese government's repressions against the Uyghurs.
On 3 May 2019, U.S. Assistant Secretary of Defense for Indo-Pacific Security Affairs Randall Schriver condemns the detention of Uyghurs as concentration camps.
On 11 September 2019, the U.S. Senate unanimously passed the Uyghur Human Rights Policy Act. On 3 December 2019, the U.S. House of Representatives passed a stronger version of the Uyghur Human Rights Policy Act by a vote of 407 to 1. The bill was signed into law on 17 June 2020.
On 8 January 2020, the Congressional-Executive Commission on China released its annual report, which stated that Chinese government actions in Xinjiang may constitute crimes against humanity.
In April 2020, United States lawmakers from the Congressional-Executive Commission on China, led by Jim McGovern and Marco Rubio, introduced the Uyghur Forced Labor Prevention Act that aims to prevent the importation of Chinese products tied to evidence of unfree labor.
In June 2020, Trump's former national security adviser John Bolton claimed that President Donald Trump told Chinese leader Xi Jinping that China's decision to detain Uyghurs in re-education camps was "exactly the right thing to do".
US Congress passed the Uyghur Human Rights Policy Act which was signed into law by President Trump on 17 June 2020. On 9 July 2020, the Trump administration imposed sanctions and visa restrictions against senior Chinese officials, including Chen Quanguo. The same month, sanctions under the Global Magnitsky Act were levied against the Xinjiang Production and Construction Corps and related officials including Sun Jinlong and Peng Jiarui.
On 14 September 2020, the U.S. Department of Homeland Security blocked imports to the United States of products from four entities in Xinjiang: all products made with labor from the Lop County No. 4 Vocational Skills Education and Training Center; hair products made in the Lop County Hair Product Industrial Park; apparel produced by Yili Zhuowan Garment Manufacturing Co., Ltd. and Baoding LYSZD Trade and Business Co., Ltd; and cotton produced and processed by Xinjiang Junggar Cotton and Linen Co., Ltd.
On 22 September 2020, the United States House of Representatives passed the Uyghur Forced Labor Prevention Act.
On 19 January 2021, US Secretary of State Mike Pompeo designated China's treatment of the Uyghurs a genocide, making the United States the first country in the world to make such a designation. China responded a day later by sanctioning US officials in the outgoing Trump administration, including Pompeo, for their criticisms of China's treatment of the Uyghurs.
On 9 July 2021 The US Department of Commerce's Bureau of Industry and Security (BIS) added 14 entities, that are based in the People's Republic of China (PRC) and have enabled Beijing's campaign of repression, mass detention, and high-technology surveillance against Uyghurs, Kazakhs, and members of other Muslim minority groups in the Xinjiang Uyghur Autonomous Regions of China (XUAR), where the PRC continues to commit genocide and crimes against humanity, to the Entity List. The Entity List is a tool utilized by BIS to restrict the export, reexport, and transfer (in-country) of items subject to the Export Administration Regulations.
Response from dissidents
On 10 August 2018, about 47 Chinese intellectuals and others issued an appeal against what they describe as "shocking human rights atrocities perpetrated in Xinjiang".
In December 2019, during the anti-government protests in Hong Kong, a mixed crowd of young and elderly people, numbering around 1,000 and dressed in black and wearing masks to shield their identities, held up signs reading "Free Uyghur, Free Hong Kong" and "Fake 'autonomy' in China results in genocide". They rallied calmly, waving Uyghur flags and posters. The local riot police pepper sprayed demonstrators to disperse the crowd.
International Criminal Court's complaint
In July 2020, the East Turkistan National Awakening Movement and the East Turkistan Government in Exile filed a complaint with the International Criminal Court calling for it to investigate PRC officials for crimes committed against Uyghurs, including allegations of genocide. In December 2020, the International Criminal Court declined to take investigative action against China on the basis of not having jurisdiction over China for most of the alleged crimes.
See also
Notes
References
External links
Xinjiang Documentation Project at the University of British Columbia
Xinjiang Data Project at the Australian Strategic Policy Institute
Regulation for the Removal of Extremism in the Xinjiang Uygur Autonomous Region (Wikisource, in Chinese)
2017 establishments in China
21st-century human rights abuses
2010s in China
2020s in China
Cultural assimilation
Human rights of ethnic minorities in China
Internment camps in China
Linguistic discrimination
Anti-Islam sentiment in China
Islamophobia in China
Political repression in China
Language policy in Xinjiang
Racism in China
Separatism in China
Total institutions
Violence against Muslims
Xi Jinping
Religious persecution by communists
Xinjiang conflict
Counterterrorism in China
Ethnic cleansing in Asia
Uyghurs
Kazakhs in China
Islam-related controversies in Asia
Human rights abuses in China
Communist repression
Collective punishment
Genocides in Asia | Xinjiang internment camps | [
"Biology"
] | 18,020 | [
"Behavioural sciences",
"Behavior",
"Total institutions"
] |
58,041,837 | https://en.wikipedia.org/wiki/Monika%20Hilker | Monika Hilker (born 24 March 1959 in Friesoythe, Germany) is a biologist and a professor at the Freie Universität Berlin. She leads the Applied Zoology/Animal Ecology working group at the Freie Universität, studying the chemical and molecular ecology of plant-insect interactions. She is also the speaker and director of the Collaborative Research Centre (CRC) 973 "Priming and Memory of Organismic Responses to Stress".
Education
Hilker received a Diploma in biology (forest zoology) at the University of Göttingen in 1983. Her research focused on visual and olfactory orientation in bark beetles. In the same year, she completed a teacher examination in organic chemistry at the same university. She remained at the University of Göttingen to conduct research on pheromones that deter oviposition in moths, receiving her doctoral degree (Dr. rer. nat.) in 1986. She completed her Habilitation (Dr. habil.) in zoology and animal ecology at the University of Bayreuth in 1993, working with leaf beetles.
Career
From 1987 to 1994, Hilker worked as an assistant professor at the University of Bayreuth. In 1994, she accepted a job as a full professor at the Freie Universität Berlin. Hilker served as a member of the DFG (German Research Foundation) senate from 2003 to 2009. She was an associate editor for the Journal of Chemical Ecology from 2004 to 2013 and served as vice president (2009-2010) and then president (2010-2011) of the International Society of Chemical Ecology. She has also been involved in initiatives to promote young researchers and women in science.
References
1959 births
Living people
21st-century German women scientists
German women biologists
Women zoologists
20th-century German zoologists
Academic staff of the Free University of Berlin
University of Göttingen alumni
University of Bayreuth alumni
Chemical ecologists
20th-century German women | Monika Hilker | [
"Chemistry"
] | 397 | [
"Chemical ecologists",
"Chemical ecology"
] |
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