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73,759,088 | https://en.wikipedia.org/wiki/Tropicamide/phenylephrine | Tropicamide/phenylephrine, sold under the brand name Mydcombi is a fixed dose combination of tropicamide and phenylephrine used to dilate the eyes (mydriasis). It contains, tropicamide, an anticholinergic, and phenylephrine, as the hydrochloride, an alpha-1 adrenergic receptor agonist. It is sprayed into the eyes.
It was approved for medical use in the United States in May 2023.
Medical uses
Tropicamide/phenylephrine is used for the short-term dilation of the pupils.
References
External links
Alpha-1 adrenergic receptor agonists
Combination drugs
Muscarinic antagonists
Ophthalmology drugs | Tropicamide/phenylephrine | [
"Chemistry"
] | 165 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
73,759,303 | https://en.wikipedia.org/wiki/Polycarbonate%20%28functional%20group%29 | A polycarbonate is an oxocarbon dianion consisting of a chain of carbonate units, where successive carbonyl groups are directly linked to each other by shared additional oxygen atoms. That is, they are the conjugate bases of polycarbonic acids, the conceptual anhydrides of carbonic acid, or polymers of carbon dioxide. They have the structure –O[(C=O)–O]n– and the molecular formula [CnO2n+1]2–.
Whereas the carbonate dianion itself is well known, as found in many salts, many organic compounds containing esters of it have been made, and the parent carbonic acid is also well-known, higher homologs are substantially less stable. Only a few examples of covalent dicarbonate and tricarbonate structures and ionic dicarbonate salts have been made and their conjugate acids have only been studied theoretically. Polycarbonates up to n=6 have been studied theoretically, with the dianions being only metastable but stabilized when paired with metal counterions or as their conjugate acids.
Di-tert-butyl tricarbonate extrudes carbon dioxide in the presence of various catalysts to form di-tert-butyl dicarbonate. Long-chain carbon dioxide oligomers are likewise expected to decompose exothermically.
References
Oxyanions
Oxocarbons | Polycarbonate (functional group) | [
"Chemistry"
] | 294 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
73,759,489 | https://en.wikipedia.org/wiki/Visual%20Arts%20Association | The Visual Arts Association, also referred to as the Visual Arts Society and VAA, formed in Dunedin, New Zealand, in 1952, for the encouragement and promotion of good design.
Background
A proposal for the establishment of a permanent national body called the Visual Arts Council, "to co-ordinate, direct and advise on all national visual art matters", had been submitted by the Auckland Society of Arts (ASA), to the Minister of Education, Ronald Algie, in 1950. "The Council should advise and make recommendations to the National Council for Adult Education and other bodies." ASA also urged that local societies be represented in regional councils. By 1954 discussion on the establishment of an Arts Council in New Zealand looked to combine some chief functions of such British organisations as the Arts Council of Great Britain, the Council of Industrial Design, and the Royal Fine Art Commission.
The Visual Arts Association (VAA) formed in Dunedin in 1952, following several meetings to establish a society to stimulate general interest in the visual arts, particularly industrial design, convened by the Adult Education Department of the University of Otago in 1951. Though a voluntary organisation, their 1952 pamphlet noted that their terms of reference were similar those of the Council of Industrial Design in Britain. They promoted design and the arts through exhibitions, lectures, panel discussions and films.
The VAA's first event in 1953, a modern room setting exhibiting locally sourced contemporary tableware and New Zealand made furniture, was installed in the lecture hall of the Dunedin Public Library. It sought to empower consumers with an appreciation of design in commonly used items. It also set the pattern for their future exhibitions.
In 1957, Oswold Stephens and the VAA organised the first exhibition of New Zealand Studio Potters at Otago Museum, Dunedin, for 16–30 November. Determined to achieve an effective standard of display, the exhibition was designed by architect Geoffrey Nees. Fifteen potters from all over New Zealand were invited to contribute—Martin Beck (Auckland), Doreen Blumhardt (Wellington), Minna Bondy (Wellington), Barry Brickell (Auckland), Len Castle (Auckland), Helen Dawson (Dunedin), Grete Graetzer (Dunedin), Doris Holland (Christchurch), Olive Jones (Onehunga), Mavis Jack (Wanganui), Helen Mason (Wellington), Patricia Perrin (Auckland), Oswold Stephens (Dunedin), Peter Stichbury (Auckland), Lee Thomson (Wellington).
Presidents
VAA chairpersons and presidents included: J E P Murphy, Tom Esplin, Charles Brasch, M J Gilbert, Margaret Mathie Dunningham and Gary Blackman.
Further reading
References
Design institutions
New Zealand design
Learned societies of New Zealand
Organizations established in 1952
Arts organizations established in 1952 | Visual Arts Association | [
"Engineering"
] | 561 | [
"Design",
"Design institutions"
] |
73,759,506 | https://en.wikipedia.org/wiki/YM-254890 | YM-254890 is a macrolide antibiotic derived from Chromobacterium species. It is used as a pharmacological research compound which acts as a selective inhibitor of Gq mediated signalling. However the claimed selectivity for Gq has been disputed.
References
Macrolides
Nitrogen heterocycles | YM-254890 | [
"Chemistry"
] | 68 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
73,759,515 | https://en.wikipedia.org/wiki/7%20Leonis%20Minoris | 7 Leonis Minoris (7 LMi) is a star located in the northern constellation Leo Minor. It is also designated as HD 82087 and HR 3764. 7 LMi is faintly visible to the naked eye as a yellow-hued point of light with an apparent magnitude of 5.86. Gaia DR3 parallax measurements imply a distance of 462 light-years and it is currently receding with a heliocentric radial velocity of . At its current distance, 7 LMi's brightness is diminished by 0.12 magnitudes due to interstellar extinction and it has an absolute magnitude of −0.03.
There have been disagreements on the object's stellar classification. 7 LMi is either a G-type giant star with a class of either G8 or G9 III, or it is a K-type giant with a class of K0 III. It is most likely on the horizontal branch (95% fit), generating energy via helium fusion at its core. It has 2.74 times the mass of the Sun but at the age of 575 million years, it has expanded to 13.41 times the radius of the Sun. It radiates 96 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of . 7 LMi has a near solar metallicity at [Fe/H] = −0.03 and it spins very slowly with a projected rotational velocity of .
7 LMi has two visual companions. AG +33°954 is a background star located much farther away than 7 LMi and it is a close spectroscopic binary itself.
References
G-type giants
Triple stars
Leo Minor
BD+34 01999
082087
046652
3764 | 7 Leonis Minoris | [
"Astronomy"
] | 362 | [
"Leo Minor",
"Constellations"
] |
73,759,559 | https://en.wikipedia.org/wiki/32%20Leonis%20Minoris | 32 Leonis Minoris (32 LMi), also known as HD 90840, is a solitary star located in the northern constellation Leo Minor. It is faintly visible to the naked eye as a white-hued point of light with an apparent magnitude of 5.78. The object is located relatively far at a distance of 729 light-years based on Gaia DR3 parallax measurements and it is currently receding with a heliocentric radial velocity of , which is somewhat constrained. At its current distance, 32 LMi's brightness is diminished by 0.14 magnitudes due to interstellar extinction and it has an absolute magnitude of −1.02.
The object has been given several stellar classifications over the years, ranging from main sequence (V) to giant star (III) and A1 to A4. Two of the classifications are A4 V and A4 III. It has 2.01 times the mass of the Sun but at the age of 465 million years, 32 LMi is now on the subgiant branch and it has expanded to 6.58 times the radius of the Sun. It radiates 241 times the luminosity of the Sun from its photosphere at an effective temperature of . 32 LMi is metal deficient with an iron abundance only 15.9% that of Sun ([Fe/H] = −0.80) and it spins modestly with a projected rotational velocity of .
References
A-type subgiants
Leo Minor
Leonis Minoris, 32
BD+39 02357
090840
051420
4113 | 32 Leonis Minoris | [
"Astronomy"
] | 329 | [
"Leo Minor",
"Constellations"
] |
73,759,578 | https://en.wikipedia.org/wiki/34%20Leonis%20Minoris | 34 Leonis Minoris (34 LMi), also known as HD 91365 or 11 H. Leonis Minoris is a solitary star located in the northern constellation Leo Minor. It is faintly visible to the naked eye as a white-hued point of light with an apparent magnitude of 5.58. Gaia DR3 parallax measurements imply a distance of 510 light-years, and it is currently receding with a poorly constrained heliocentric radial velocity of . At its current distance, 34 LMi's brightness is diminished by interstellar extinction of 0.16 magnitudes and it has an absolute magnitude of −1.02.
The object has received several stellar classifications over the years. Most sources generally agree that it is an early A-type main-sequence star with the classes ranging from A0 to A2. Anne Cowley and colleagues found that 34 LMi has broad or nebulous absorption lines in its spectrum, which could be a result of rapid rotation. However, D. R. Palmer gave a class of A0 IV, indicating that it is an evolved A-type subgiant. Richard O. Gray and Robert F. Garrison found a class of A1 III-IV, indicating that it has a luminosity class intermediate between a subgiant and giant star.
34 LMi has 2.4 times the mass of the Sun and an enlarged radius of . It radiates 323 times the luminosity of the Sun from its photosphere at an effective temperature of . At the age of 406 million years 34 LMi is 1.9% past its main sequence lifetime, meaning that it has evolved to the subgiant branch. The star has a near-solar metallicity at [Fe/H] = −0.03 (93% solar). Like many hot stars 34 LMi spins rapidly, having a projected rotational velocity of .
References
A-type subgiants
Leo Minor
Leonis Minoris, 34
BD+35 02154
091365
051685
4137 | 34 Leonis Minoris | [
"Astronomy"
] | 417 | [
"Leo Minor",
"Constellations"
] |
73,761,200 | https://en.wikipedia.org/wiki/Armored%20Train%20Regiment%20%28Estonia%29 | The Armored Train Regiment (Estonian: Soomusrongirügement) was an armored regiment of the Estonian Defense Forces from 1934–1940. In 1939, the strength of the regiment was 544 men. The symbol of the regiment was a skull with wings on train wheels, symbolizing how armored trains fought in the Estonian Independence War.
History
Creation
The Armored Train Regiment was created on November 30, 1934, when the in Tapa was merged with the into the Armored Train Regiment in Tapa.
Sports
In 1938, the regiment participated in 27 sports competitions, including 16 football matches, of which the regiment won 11. The regiment was also involved in shooting sports.
20th Anniversary
On November 29, 1938, the Armored Train Regiment celebrated the 20th anniversary of the armored trains of Estonia, which date back to 1918 during the Estonian Independence War. Major General Aleksander Pulk, commander of the 1st Division spoke at the regiment's sports field. Around 100 veterans who were personnel of the armored trains during the Independence war attended. A parade was held on the regiment's sports field. Lunch was offered to the veterans after the parade. Colonel Karl Parts, who led and organized armored trains during the Independence War, gave a speech about Rear Admiral Johan Pitka, who is often called "the father of the armored trains". Parts ended his speech by remembering the fallen personnel of the Armored trains in the Independence War and the actions of Captain Anton Irv, who died in 1919. Other military figures, including General Johan Laidoner, Lieutenant general Paul Lill, and Lieutenant general Nikolai Reek sent telegrams. The celebration continued until the next day on November 30, 1938.
Disbandment of the regiment
In June 1940, the Soviet Union invaded and annexed Lithuania, Latvia, and Estonia. The Estonian army was formed into the 22nd Rifle Corps and the 22nd Territorial Rifle Corps of the Red Army. The regiment was dissolved and it's artillery cannons were transferred to Russia. During the June Deportation, the regiment's commander from 1936 to 1940, Voldemar Karl Koch (later Koht), was arrested and deported to Siberia in June 1941. Koch was executed in Norilsk in September 1942. The regiment's commander from 1940 to 1941, , was arrested and deported by the NKVD. Toffer died later in 1945.
Organisation
The regiment was located in Tapa, and it consisted of two divisions, each with their own machine gun and infantry companies:
First Division
The First Division consisted of 2 armored trains, a machine gun company, and infantry company.
Armored Trains
The armored train(s) of the First Division was Broad-gauge armored train "Kapten Irv" (nr. 1) and Broad-gauge armored train nr. 2.
Second Division
The Second Division consisted of 1 armored train, a machine gun company, a heavy long-range artillery company, and infantry company. The Chief of Staff of the Second Division was the former commander Voldemar Karl Koht from 1940 to the occupation of Estonia during the Second World War.
Heavy Long Range Battery
The (Estonian: Raskekauglaskepatarei) was a long-range artillery unit, which included three artillery wagons. The cannons came from former naval artillery pieces. These artillery wagons were used for long range bombardment and could fire two times as farther than the cannons of the artillery wagons.
Armored Trains
The armored train(s) of the Second Division were Broad-gauge armored train nr. 3.
Equipment
In 1940, the regiment had 16 Maxim M1910 heavy machine guns.
Cannons and Artillery
In the late 1930s, the Armored Train Regiment had a total of 16 artillery wagons, 8 light, 4 mixed, 4 heavy artillery.: The regiment also had 3 naval artillery pieces
Armored trains
There were 3 armored trains in the regiment:
Broad-gauge armored train nr. 1 (Named 'Kapten Irv' after Anton Irv after his death in 1919).
Broad-gauge armored train nr. 2
Broad-gauge armored train nr. 3
Notes
References
External links
Tapa Museum page about the regiment (in Estonian)
Estonian Land Forces
Armoured warfare
Military units and formations established in 1934
Railway troops
Military units and formations disestablished in 1940
Regiments of Estonia
Armored regiments
Military units and formations of Estonia | Armored Train Regiment (Estonia) | [
"Engineering"
] | 862 | [
"Military engineering",
"Railway troops"
] |
73,761,732 | https://en.wikipedia.org/wiki/Martin%20Schoell | Martin Schoell is a German geochemist. His research focuses on using stable isotopes to characterize the geochemistry of petroleum. Schoell is known for his work regarding CO2, sedimentary rocks, methane, natural gas, carbon isotopes, and acetate fermentation and how these factors enable identification of the origins of greenhouse gasses. Schoell was the founder, CEO and president of Gas Consult International, Inc., a private natural gas consulting firm, from 2001 to 2015. Schoell was awarded the Alfred Treibs Award by the Geochemical Society in 2008.
Education
Martin Schoell attended University of Munich for his undergraduate career in 1961 and in 1964 attended the University Clausthal, Germany for graduate school where he obtained a PhD in geochemistry. While at the University Clausthal, in 1966 Schoell delivered his Diplomarbeit (Master's Thesis) on the geochemistry of strontium in a deposit of barite. Later, in 1981, Schoell continued his education in Germany by obtaining his Habilitation (the highest possible academic degree offered in German academia). Schoell was mentored by Wolfgang Stahl, who inspired Schoell's interest in hydrogen isotope geochemistry with respect to natural gas research.
Career
Following his completion of his PhD, Schoell began working for the German Geological Survey focusing on hyper saline hydrothermal vents in the Red Sea. From 1984 to 2001, Schoell worked for Chevron Oil Field Research Company in La Habra. During this time, he published his most cited paper, "Biogenic methane formation in marine and freshwater environments: CO2 reduction vs. acetate fermentation—Isotope evidence". In this paper, Schoell et al. discussed how hydrogen and carbon isotope composition analysis can be used to identify different biogenic methane production pathways from its water and CO2 precursors. This paper went on to win the 1995 AAPG Best Paper Award. In addition to this, while working for Chevron in 1984 Schoell requested funding from Chevron to fund John Hayes of Indiana University to develop continuous-flow compound-specific isotope analysis. This development allowed Schoell to make a variety of discoveries including the ability of steranes and hopanes in the Lacustrine Green River Formation could be used as a proxy for water paleo-depths.
During his time with Chevron, Schoell introduced Mudgas isotope analysis to Chevron and the natural gas industry, and worked in a variety of international locations including locations throughout the Americas, Southeast Asia and Africa as well as parts of Oceania.
In 2001, Schoell went on to establish a natural gas consulting company, GasConsult International, Inc. of which he was the CEO and president of until 2015. GasConsult specializes in ZR-LNG (zero-refrigeration liquified natural gas), LH2 (liquid hydrogen) and OHL (optimized liquid hydrogen) technologies and offers clients opportunities to transition to these technologies, and is now under the direction of Bill Howe.
In 2019, Schoell founded GasXpse which applies geochemical fundamentals to provide natural gas related consulting services and provide scientific advising for natural gas-related subjects. Further, Schoell has co-authored 76 publications in the field of geochemistry.
Research
Schoell has made many contributions to geochemistry with emphasis on the applications of stable isotope analysis. The results of Schoell's work have included identifying the pathways of formation that distinguish methane of biogenic origin from that of thermogenic origin using stable isotope analysis. In the paper, "Biogenic methane formation in marine and freshwater environments: CO2 reduction VS. acetate fermentation-Isotope evidence", Schoell et al. identify that the two primary methods for aquatic and marine methane production are carbon dioxide reduction and acetate fermentation, respectively. By recognizing the difference in δ13C and δD fractionation of the water environments and observing the differences in δ13C and δD fractionations of the methane product, Schoell et al. concluded that the dominant pathway of methane in marine environments is via acetate fermentation, while methane in freshwater environments arises from CO2 reduction. By analyzing the CH4 and H2O fractionation, Schoell, et al. offer a technique for identifying the original environment in which methane was produced.
Schoell continued his work with methane origin studies expanding his research to consider how stable isotopes can provide insight regarding the temperature of the environment for both thermogenic and biogenic methane production. Specifically, Schoell collaborated on the paper "Formation temperatures of thermogenic and biogenic methane" authored by D. Stolper, which used "clustered isotope" techniques to determine the temperature at which methane was produced. This approach has become useful for identifying the thermal conditions of methane formation for both the high temperatures of thermogenic methane production and the relatively lower temperatures of microbial methane production as well as characterizing the contribution of both producers to a mixed sample.
While the majority of Schoell's work has revolved around identifying the origins and pathways of methane production, he has also done work using stable isotope analysis to address how environmental factors affect preservable products of biological activity. Schoell addresses this topic in the paper, "Sensitivity of biomarker properties to depositional environment and/or source input in the Lower Toarcian of SW-Germany". In addition to this, his career has included the research of how stable isotope analysis can be used to identify the mixing and composition of natural gasses, as discussed in "Use of Gas Isotope Analyses for Reservoir Management".
Personal life
Schoell was born in Germany, although the bulk of his career and adult life he has spent in the United States. Since retiring, Schoell resides in California. Aside from his research, Schoell has experience in winemaking.
Awards
Schoell received the 1995 AAPG Best Paper Award and was recognized by the American Association of Petroleum Geologists as authoring one of the top twenty most notable geology-related papers of the 1980s. Specifically, the AAPG recognized Schoell for his paper "Genetic Characterization of Natural Gasses" which describes how the correlation between C2+ concentration, the variation of carbon and hydrogen isotopes in methane, and carbon isotope variation in ethane can be used to qualitatively characterize the composition of natural gasses.
In 2008, Schoell received the annual Alfred Treibs Award. This award is given on a yearly basis by the Geochemical Society in recognition of scientists whose research has made significant contributions to the understanding of geochemical processes. Schoell received this honour in response to his work with stable isotope analyses which revolutionized fossil fuel research and greenhouse gas tracing.
References
Wikipedia Student Program
Geochemists
Clausthal University of Technology alumni
Chevron Corporation people
German expatriates in the United States
Year of birth missing (living people)
Living people | Martin Schoell | [
"Chemistry"
] | 1,434 | [
"Geochemists"
] |
73,761,875 | https://en.wikipedia.org/wiki/Lam%C3%A9%27s%20theorem | Lamé's Theorem is the result of Gabriel Lamé's analysis of the complexity of the Euclidean algorithm. Using Fibonacci numbers, he proved in 1844 that when looking for the greatest common divisor (GCD) of two integers a and b, the algorithm finishes in at most 5k steps, where k is the number of digits (decimal) of b.
Statement
The number of division steps in the Euclidean algorithm with entries and is less than times the number of decimal digits of .
Proof
Let be two positive integers. Applying to them the Euclidean algorithm provides two sequences and of positive integers such that, setting and one has
for and
The number is called the number of steps of the Euclidean algorithm, since it is the number of Euclidean divisions that are performed.
The Fibonacci numbers are defined by and
for
The above relations show that and By induction,
So, if the Euclidean algorithm requires steps, one has
One has for every integer , where is the Golden ratio. This can be proved by induction, starting with and continuing by using that
So, if is the number of steps of the Euclidean algorithm, one has
and thus
using
If is the number of decimal digits of , one has and
So,
and, as both members of the inequality are integers,
which is exactly what Lamé's theorem asserts.
As a side result of this proof, one gets that the pairs of integers that give the maximum number of steps of the Euclidean algorithm (for a given size of ) are the pairs of consecutive Fibonacci numbers.
References
Bibliography
Bach, Eric (1996). Algorithmic number theory. Jeffrey Outlaw Shallit. Cambridge, Mass.: MIT Press. .
Carvalho, João Bosco Pitombeira de (1993). Olhando mais de cima: Euclides, Fibonacci e Lamé. Revista do Professor de Matemática, São Paulo, n. 24, p. 32-40, 2 sem.
Theorems in number theory
Algorithms
Information technology
Number theoretic algorithms
Euclid | Lamé's theorem | [
"Mathematics",
"Technology"
] | 416 | [
"Information and communications technology",
"Mathematical theorems",
"Algorithms",
"Mathematical logic",
"Applied mathematics",
"Theorems in number theory",
"Information technology",
"Mathematical problems",
"Number theory"
] |
73,761,994 | https://en.wikipedia.org/wiki/Siris%208 | Siris 8 is a discontinued operating system developed by the French company CII for its Iris 80 and Mitra 15 computers. It was later replaced by Honeywell DPS 7.
Jean Ichbiah worked at CII on the rewrite of the Siris 7 operating system of the Iris 80 to create a more successful version, used to operate a three processor Iris 80 in Évry.
The first version of Siris 8 offered full compatibility with applications running on its predecessor Siris 7. Among its strong points were its excellent memory management, which took advantage of the extended virtual addresses and spaces of the Iris 80.
Siris 8 was suitable for both scientific and business computing, as well as real-time applications.
The first delivery of the uniprocessor version occurred in February 1972, and the dual-processor version in September 1972 for the French Atomic Energy Commission (CEA) . Siris 8 also included , networking software for transporting data to other computers.
After the CII merger with Honeywell-Bull, the functionality of Siris was adapted for the GCOS system through an emulation processes, which made it possible to retain all of the Siris 8 customers. The final version of Siris 8, C10, was shipped in 1976.
Characteristics
Before demand paged virtual memory was added in 1975, Siris 8 was described as having "two core partitions... one for resident 'batch' tasks, one for swapped time-shared tasks."
It operated in four separate modes:
Batch processing comprising, local and remote
Transaction processing
Time sharing
Real-time processing.
The Siris 8 monitor consisted of a permanently resident portion and pageable segments.
Batch jobs could be entered through the local or a remote card reader, or by the console operator. Timesharing could be started and stopped by the operator. A timesharing job was started by the DEMON task, which performed all terminal I/O. The system maintained three types of queues of work. The multiprogramming queue could run multiple jobs at a time, with jobs scheduled by priority. One to five Operational queues () could run one job in each at a time, queued strictly by arrival time. A cataloged job queue was used for jobs submitted by the console operator; multiple jobs from this queue could be active at one time.
Real-time jobs had access to special system services such as "[s]witching from slave mode to master mode and vice versa, time delays, abort recoveries."
Transaction processing was performed by a subsystem called STRATEGE.
The virtual address space available to the user could be up to 32 segments of 128 K (32-bit) words, or 16 MB.
References
Mainframe computers
Discontinued operating systems
History of computing in France
External links
Siris 8 description from the original commercial brochure, Fédération des Equipes Bull (translated to English) | Siris 8 | [
"Technology"
] | 590 | [
"Operating system stubs",
"Computing stubs",
"History of computing",
"History of computing in France"
] |
73,762,354 | https://en.wikipedia.org/wiki/Inca%20kancha | A kancha is an Inca rectangular or trapezoidal walled enclosure composed of single-room buildings that face onto a common open courtyard or inner patio in the middle of the enclosure. Kanchas are widespread in the Inca Empire and normally have only one entrance gate. An Inca kancha includes constructions intended for a single function: housing, temples, palaces. In Cusco, the capital of the Empire there existed many kanchas, among them the Coricancha, the Sun temple, the Hatunkancha that housed the house of the acclas (chosen women of the sun) and Amarukancha, the large hall facing the main square called Huakaypata. Other notable kanchas are found in Ollantaytambo and Patallaqta.
Kanchas could have quite different sizes ranging from a large city block to a small enclosure. Also the number of buildings within a kancha varies, including up to eight or more structures. Kanchas were sometimes laying side by side forming a larger unit, or a block. These were generally surrounded by streets or alleys and the entrances to single kanchas would lay on different sides.
While remains of kanchas are found in all the settlements in the territory of the Inca Empire, the best preserved examples are found in Ollantaytambo which, although modified, are still inhabited.
The origin of kanchas may have derived from pre-Inca coastal architecture, especially from the Chimú culture, which flourished between 900 CE and the conquest by the Inca emperor Topa Inca Yupanqui around 1470 or from the Wari culture which developed in the south-central Andes and coastal area of modern-day Peru, from about 500 to 1000 CE.
The name kancha is a Quechua term meaning patio or courtyard bordered by a wall. In modern Spanish the term refers to a sport playground such as for football or tennis, recalling the enclosed space.
Layout and distribution
The presence of kanchas was ubiquitous in Cusco and in other Inca settlements. Some of them were regarded as "palaces" by the Spanish chroniclers. Among them Bernabé Cobo stated «the main houses of the caciques (native lords) […] had large patios − where the townspeople gathered to drink during their festivals and celebrations − and more rooms».
The Inca people gave great importance to open spaces for their social life. Even the first Quechua dictionaries by Santo Tomás and González Holguín have different words for open spaces: to describe an open, common space translated into Spanish as 'plaza' or a place where there are no houses or a space for eating, drinking and merrymaking; normally referred to a terrace, an andén or an elevated area, and finally "kancha" with the meaning of space delimited by buildings
The most sacred temple in Cusco the Coricancha (also spelled Kancha) meaning the golden enclosure was in its layout a kancha, the one with the highest symbolic hierarchy: an area of about enclosed by a stone wall with a central patio bordered by six single room shrines, each of them dedicated to a god of the Inca pantheon. It served as a model for the temples in other planned Inca settlements.
Also the Cusco palaces built in the sacred part of the city, that was between the two rivers Saphi and Tullumayo, large kanchas were positioned having the extension of a city block. A single gate gave access to each compound providing also adequate security.
Despite important modifications carried out by the Spaniards by splitting into smaller properties and opening of more access gates, extensive remains of the fine stonework enclosing walls are found in Cusco. Many colonial buildings in Cusco have a lower floor which is the original Inca building and a first floor with a balcony or loggia built according to the Spanish tradition representing the stratification which allows for cultural continuity in the Cusco architecture.
In various archaeological sites there are remains of building groups that show the layout of a kancha. Sometimes these are well defined, with enclosure walls and a single entrance, other times, where there is no evidence of the enclosing wall, the remains of two, three, or more separate one-room buildings stand around a patio. In Patallaqta, for example, there are repetitive groups formed by two small houses, one in front of the other, looking towards a patio; groups of three rectangular constructions arranged as a U around a patio; and finally, groups of four one-room buildings that form a quadrangular courtyard. This type of arrangement is very frequent in the roundabouts of Cusco in the settlements of the Urubamba river valley (Sacred valley), but the same characteristic is also repeated in settlements far away from the capital.
It can be stated that the rectangular kancha layout was the basic of the Inca living space both for family needs and for palaces and temples. Thus it remains a challenge for archaeologist to understand, when discovering new kancha-like structures to understand what their functions were. The function of the hundreds of kanchas in Huánuco Pampa is still a puzzle for archaeologists
Origin of kanchas
It has been suggested That the origin of kanchas may derive from pre-Inca coastal architecture, especially from the Chimú culture, which flourished between 900 CE and the conquest by the Inca emperor Topa Inca Yupanqui around 1470 or from the Wari culture which developed in the south-central Andes and coastal area of modern-day Peru, from about 500 to 1000 CE. The northern pre-Inca kanchas have an enclosure wall but a different internal layout.
Hyslop underlines that the Cusco kanchas were developed before a contact between the Incas and the Chimu civilization was established and he sees «little solid proof to suggest that the origins of the kancha are to be found on the north coast».
Hyslop suggests another possible origin: the rectangular enclosures and the grid arrangement are found in the per-Inca Wari culture in the southern Peruvian Andes, close to Cusco. The Incas modified the Wari model e.g. building lower walls, before distributing them as a typical Inca architecture form, in all the Inca empire.
Kanchas in Ollantaytambo
The best-preserved example of kanchas is found in the planned settlement of Ollantaytambo.
Each rectangular block is surrounded by alleyways on all four sides and contains two completely independent kancha units with a single entrance for each unit facing opposite streets.
The two units repeat symmetrically the same layout: they consist of four rooms placed around a patio. The only entrance gives access to a construction that today, in all the sets, is the most destroyed. In the patio, two equal rooms, one facing the other are found and, in the background, the main house with barn has a dividing wall that separates one housing unit from the other. Consequently, only one of the two slopes of the roof of the house corresponds to one of the housing units.
The entrance gate to the kancha have double jambs, and the doors of the rooms around the patio have monolithic lintels. Both kinds of gates have a remarkable height.
These measures, together with the quality of the stonework, do not allow to classify these constructions as rural houses, but nothing is known as the hierarchical level of its original inhabitants is concerned.
Today, although partly modified, without their imposing thatched roofs and deteriorated, they are inhabited by peasant families from Ollantaytambo, making this probably the oldest case of continuous occupation in all of South America.
See also
Inca architecture
Kallanka
Tambo
Qullqa
Pukara
Ushnu
References
Inca
Architectural history
Architectural styles
Archaeological sites in Peru
Pre-Columbian architecture | Inca kancha | [
"Engineering"
] | 1,588 | [
"Architectural history",
"Buildings and structures by type",
"Construction",
"Infrastructure",
"Architecture"
] |
73,762,558 | https://en.wikipedia.org/wiki/Biscogniauxia%20atropunctata | Biscogniauxia atropunctata, the hypoxylon canker, is a species of sac fungus in the family Graphostromataceae. Like many other fungi in the genus, it is a plant pathogen; specifically this species can cause Biscogniauxia (Hypoxylon) canker and dieback disease in host trees.
Taxonomy
Biscogniauxia atropunctata contains the following varieties:
Biscogniauxia atropunctata maritima
Biscogniauxia atropunctata atropunctata
Description
Patches of the fungus can reach a few metres across. It is white, sometimes with black patches, and usually with a black margin.
Similar species
In addition to other species within the genus, Diatrype stigma, Camarops tubulina, Kretzschmaria deusta, and species of Camillea can appear similar, as can Arthonia lichens.
Distribution
This species is found in spring and early summer east of the Rocky Mountains of North America.
Ecology
When not pathogenic, Biscogniauxia atropunctata is saprobic on oak and other hardwood trees, causing a white rot on the host deadwood. The fruiting body grows in patches with a whitish-gray surface covered by black dots that grow to be blackened overall.
The fungus can colonize healthy trees and live undetected and harmlessly in the bark and sapwood for some time, its spread kept in check by the host's natural defenses. However, when the trees become stressed, the fungus invades weakened host tissues, causing the dieback disease. Initially the infection kills affected branches, then progresses down the trunk to form a canker, girdling the tree and killing the entire crown.
References
Xylariales
Fungi of North America
Fungal plant pathogens and diseases
Fungal tree pathogens and diseases
Fungus species | Biscogniauxia atropunctata | [
"Biology"
] | 393 | [
"Fungi",
"Fungus species"
] |
73,763,883 | https://en.wikipedia.org/wiki/Arman%20Soldin | Arman Soldin (21 March 1991 – 9 May 2023) was a Bosnian–French journalist killed at the age of 32 by a Russian-fired Grad rocket while reporting for Agence France-Presse in Ukraine near the city of Chasiv Yar, Donetsk Oblast during the Russian Invasion. His death was noted and deplored by journalists worldwide and by international leaders. France posthumously awarded him the Legion d’Honneur (Legion of Honour).
Early life
Soldin was born on 21 March 1991 in Sarajevo, SR Bosnia and Herzegovina. He was evacuated with his mother Oksana (later a philosophy and sociology professor) to France on 25 April 1992, at the age of 12 months. The family returned to Bosnia after the ethnic conflict 6 years later, where Soldin attended primary school, but after the divorce of his parents in 2002, he lived in Rennes in Brittany. In addition to Bosnian as his native language, Soldin spoke French, English, and Italian. Precociously interested in news and journalism, at 16 he created a YouTube compilation Sarajevo in War, set to Italian composer Tomaso Albinoni's mournful Adagio.
Education
Soldin took the French Baccalaureate, specialising in Science, with an upper second class honour at the Lycée Saint Martin, Rennes, 2006–2009. In 2013 at University College London he attained a BA in Politics & Eastern European Studies with Politics, Economics, History, and International Relations. While there, he was co-editor in chief of its Eureka Magazine, covering politics, society, arts and culture.
At the Academy of Sciences and Arts of Bosnia and Herzegovina, University of Sarajevo his 2014 MA was in Production and Management in performing arts, and cinematography and production in film and video; then in 2014–15 he graduated from the Université Lumière, Lyon with a Masters in Journalism – New Journalistic Practices.
Career
Arman Soldin joined Agence France-Presse in 2015 as an intern in Rome and is remembered there by video reporter Sonia Logre as "a dream intern," who "wanted to do everything, see everything, know everything. He wanted humbly to learn, had a desire to discover Italy and a deep love of life." He reported on African refugee arrivals at the small Italian island of Lampedusa. He then worked for the agency's London office, reporting in June 2018 on the stand-off between the Italian government and the Lifeline humanitarian ship with 233 migrants on board, many ill, when it arrived in Malta after a week of waiting in the Mediterranean, and in October on Nationalist Milorad Dodik winning the seat reserved for Serbs in the Bosnian collegiate presidency. In 2019 he broke a story on the thirty-nine bodies, including that of a teenager, discovered in east London in a refrigerated lorry from Belgium. During the emergence of Brexit he wrote in December 2019 on Scottish Prime Minister Nicola Sturgeon's opposition and her bid for a plebiscite on Scottish independence. From 2020 he was again posted to Rome.
Known as a gifted junior footballer for Stade Rennais in western France from 2006 to 2008, he ceased competition due to a knee injury, but used his experience as a sports commentator 2021–2023 on English Premier League, UEFA Women's Euro, UEFA Super Cup matches for Canal+ France. It was work he also conducted in between postings to Ukraine.
Ukraine
As the Russian invasion started in February 2022, Arman volunteered immediately to be among the France-Presse agency's first special envoys. He was later rotated, against his wishes, but returned to Ukraine in September 2022, working as a video coordinator. Frequently he used his mobile phone to record subjects who would otherwise be intimidated by a video camera, such as a woman digging in her garden in Chasiv Yar, or former welder Oleksandr delivering bread to sheltering civilians on his moped in Donbass. In Kherson in December 2022, Soldin produced video for AFP of risky civilian rescues of Ukrainians stranded on islands in the Dnieper River after Russian troops retreated in November to the other side of the Dnieper, but kept snipers and artillery trained along the river, rendering it a new front line. His coverage in January 2023 showed an intense Russian offensive on Soledar, and Vuhledar, in the eastern Donetsk Oblast. In April 2023 he covered Ukrainian soldiers digging defences near Bakhmut.
Soldin was an avid social media user. One of the stories which received attention was when he and his team found an injured hedgehog in a trench, fed and released it into the wild after a couple of days. In memory of AFP video reporter Arman Soldin, Olha Chevhaniuk of the UAnimals NGO announced a ₴100,000 (€2,475.13) grant for volunteers and shelters for the rescue of hedgehogs in war zones. She said: We corresponded the day before yesterday, and today he died. Last week, French journalist Armand Soldin wrote to us and shared a video of how he and his colleagues rescued an exhausted hedgehog in a trench. He cured the animal and later released it into the wild. We edited a small story based on Arman's video, and it touched many of our subscribers. He thanked us, and we rejoiced at his kindness. And we just found out that Arman died. It was a numbing shock...we only knew each other online, but we had time to feel how kind and devoted this person was. When the news of Armand's death came out, we consulted and decided to at least symbolically honour his memory.
Death
On 9 May 2023, the team was near the city of Chasiv Yar, Donetsk Oblast, together with a detachment of Ukrainian soldiers. Soldin was killed by a Grad rocket which exploded near the place he was lying. Nobody else was injured. Emmanuel Peuchot, an experienced war correspondent who joined the team last October reported that Soldin died "with his camera in his hand", "his face showing no signs of suffering." Soldin was 32.
Gulnoza Said, the Committee to Protect Journalists' Europe and Central Asia program coordinator in New York City responded to news of his death with the statement:The Committee to Protect Journalists is profoundly saddened by the death of journalist Arman Soldin while covering the war in Ukraine. We extend our deep condolences to his friends and family. Journalists are civilians whose reporting from war zones is essential. We call on Russian and Ukrainian authorities to thoroughly investigate the circumstances of Soldin’s death.The CPJ noted that Soldin is the 17th journalist to be killed in Ukraine since 2022. Reporters Without Borders global news director Phil Chetwynd remarked that;Arman's brilliant work encapsulates everything that makes us so proud of AFP journalism in Ukraine. Arman's death is a terrible reminder of the risks and dangers of reporting on this war.The killing of Arman Soldin was condemned by the Director-General of UNESCO Audrey Azoulay in a press-release published on May 10, 2023. UNESCO's mandate to "promote the free flow of ideas by word and image" includes the protection of journalists and media workers against any forms of attacks and reprisals related to their duties. The facts and circumstances surrounding this killing are categorized and archived online on UNESCO's Observatory of Killed Journalists. The Observatory archives publicly accessible information on all the journalists killed in relation to their duties since 1997, where the Director-General has issued a condemnation.
Agence France-Presse director for Europe Christine Buhagiar remembered Soldin as "enthusiastic, energetic and courageous," and journalists and staff of AFP in Paris and across the world held a minute of silence on 11 May to remember their colleague. French President Emmanuel Macron used Twitter to announce that "a journalist from Agence France-Presse, one of our compatriots, Arman Soldin, was killed in Ukraine. With courage, from the first hours of the conflict he was at the front to establish the facts," and that "we share the pain of his loved ones and his colleagues". On 1 June 2023, in its Paris headquarters, AFP conducted a memorial ceremony for Soldin, and announced that in the following week its journalists would return to frontline reporting in Ukraine. AFP Information Director Phil Chetwynd emailed agency employees, detailing the circumstances of his death; Arman died from Grad rocket fire near the village of Chasiv Yar in eastern Ukraine, while our team of four journalists moved away from the front lines, escorted by two Ukrainian soldiers, ... his colleagues on the ground believe that he may have tried to reach the trench a few meters ahead, instead of throwing himself to the ground ... the rocket fell very close to Arman and he died almost instantly.White House spokeswoman Karine Jean-Pierre said that the "world owes a debt to Arman Soldin, an AFP journalist who lost his life today on the front line of the war in Ukraine...journalism is one of the foundations of a free society".
According to global monitoring on the safety of journalists achieved by the Observatory of Killed journalists, Soldin was the 3rd media professional killed in Ukraine in 2023.
French anti-terror investigation unit the Central Office for Combating Core International Crimes and Hate Crimes (Office central de lutte contre les crimes contre l'humanité, OCLCH). have launched a war crime investigation into the death of Soldin and will probe the circumstances of Soldin's death, the prosecutors said.
Soldin is survived by his mother Oksana, his sister Ena, and younger brother Sven.
References
1991 births
2023 deaths
21st-century French journalists
French people of Bosnia and Herzegovina descent
University of Sarajevo alumni
Alumni of University College London
Journalists killed while covering the Russian invasion of Ukraine
Civilians killed in the Russian invasion of Ukraine
Deaths by Russian airstrikes during the Russian invasion of Ukraine
Journalists from Sarajevo
Deaths from explosion
Bosnia and Herzegovina emigrants to France
Sports commentators
Agence France-Presse journalists
University of Lyon alumni
French war correspondents
Knights of the Legion of Honour | Arman Soldin | [
"Chemistry"
] | 2,106 | [
"Deaths from explosion",
"Explosions"
] |
70,819,873 | https://en.wikipedia.org/wiki/Diorama%20Arts%20Cooperative | Diorama Arts Cooperative (DAC) was a mixture of actors, artists, dancers, designers, journalists, musicians and therapists who used the Diorama theatre in Regent's Park between 1976 and 1992. In September 1981, DAC was incorporated as the charity Diorama Arts Centre.
According to the Theatres Trust, "In the 1970s, the arts collective created a small theatre within a lively arts centre, widely known as a place for arts, craft, theatre, concerts and more." The book The Diorama Arts Project said, "Diorama arts is a community arts group particularly concerned with the handicapped and under-privileged, which plans to convert the Regents Park Diorama building for use as its headquarters."
At Christmas 1992, Diorama Arts Centre left the building; its landlords, the Crown Estate Commissioners and Camden Council relocated the organisation to a new development nearby in Osnaburgh Street. The Old Diorama Arts Centre, now at the Regent's Place campus, continues the charity.
Timeline
Building
The building taken over by the DAC was originally used by Louis Daguerre, a pioneer of photography. Designed by John Arrowsmith and built by Morgan & Pugin, the Diorama exhibited paintings by Daguerre and Bouton. The brick building was polygonal in shape, and its frontage is visible in a long row of Regency-era buildings designed by John Nash. The popular, short-lived form of visual entertainment consisted of painted scenes dramatised with lighting and other effects. Artist John Constable, who attended the first showing in September 1823, wrote to his friend Archdeacon Fisher: "It is in part a transparency, the spectator is in a dark chamber, and it is very pleasing and has great illusion..."
Daguerre's diorama closed in 1848 due to falling income, and by 1854 had been converted into a Baptist chapel. The chapel closed in 1922 and was taken over by the Red Cross, who joined with Middlesex Hospital. During the 1920s, Thomas Pole designed the Octagon in the Diorama; a rheumatism-treatment hydrotherapy pool was installed, and the hospital left the building by 1964. In 1965, Bedford College moved in their Geography, Zoology and Social Research Departments; the college left . The Octagon's internal shape was used by the DAC, and a resident cafe was later named after it.
1976 to 1981
By c.1976, an arts cooperative had taken over the Diorama. According to a New Statesman article, "The Crown granted annual leases to some dyslexia therapists who used music and drama; gradually the building filled with artists and therapy groups who paid small rents (to cover the cost of the upkeep) to the collective which became Diorama Arts." Poet and drama therapist Larry Butler remembered his involvement: "Before coming to Glasgow in 1981, I was the founder and warden of the Diorama Arts Co-operative, director of PlaySpace Trust and Matchbox Theatre."
Former Matchbox Theatre member Hazel Carey wrote in her book, Ubuntu: my life in other people,
The website My Camden said, "In the late seventies artists and performers took up residence in the Diorama building by Regent's Park, developing a co-operative approach to the arts, education, therapy, and disability arts."
1981 to 1992
After a Crown Estate Commissioners (CEC) request, Diorama Arts Centre was incorporated as a charity and company on 15 September 1981; in 1982, a rental agreement was formalised. Until then, it had a peppercorn rent of about £25 per year.
In 1983, the group faced eviction; Greycoats Estates, acting for the CEC, sought to redevelop the Diorama into offices. DAC fought the attempted eviction, and won the case in 1984 after a public inquiry by the Department of the Environment.
Helped by URBED's (Urbanism, Environment and Design Ltd.) 'Re-use of Industrial Buildings Service' by February 1984, the Diorama Arts Trust was formed to propose a scheme which resulted in a £4 million fundraising effort through and beyond 1984.
CAST (Cartoon Archetypical Slogan Theatre, led by Roland Muldoon) agreed to become members of Diorama Arts in June and July 1984. In August 1984, the CEC began an appeal to reverse Camden Council's (CC) failure to allow renovation of the Diorama. CC's director of planning and communications refused a planning application submitted by Hunter & Partners on behalf of the CEC in August 1986.
The National Archives has a catalogue "The Diorama, Regent's Park" covering the dates 1 December 1985 to 31 December 1988. The website Library of Book refers to "Diorama Arts Trust Correspondence May 1986 To October 1990": "Correspondence from the Diorama Arts Trust (of which Denys Lasdun was a patron) over the future of the historic Diorama building in Regents Park."
On 25 January 1990, the Diorama Arts Trust held a press conference which included a press release, a list of trust members and reactions to the trust's plans to preserve the Diorama. According to the Old Diorama website, "... Diorama Arts Centre Ltd. combines a wide range of artistic activities organised in such a way as to provide a self-funding public building dedicated to the arts. Only after several years of campaigning through the courts and in the community have we been able to rescue the building from neglect, obscurity and demolition." At Christmas 1992, Diorama Arts Centre left the building as the CEC and CC relocated the organisation to a new development in nearby Osnaburgh Street.
Music
Elvis Costello wrote in his song, "London's Brilliant Parade", "The lovely Diorama is really part of the drama, I'd say". Percussionist Jon Keliehor of Matchbox Theatre began a music studio around 1976, which continued until 1984 and was later called the Diorama Percussion Music Research Unit. During his time at the Diorama, Keliehor continued writing music for dance, drama and theatre. Through his involvement with the London Contemporary Dance Theatre, early support came from co-founder and CEO Robin Howard. The 1977 Many Ways of Moving conference resulted in the Diorama becoming a centre of the alternative dance movement network.
Between 1976 and 1992, musicians who played at the Diorama included:
Nick Cave and the Bad Seeds played on 30 October 1984. It was Cave's third appearance. Other performers included Lydia Lunch and Jessamy Calkin.
The Bow Gamelan Ensemble performed in the summer of 1985, and was reviewed in Performance Magazine.
Billy Bragg, as part of the Red Wedge tour, played on 11 January 1986. The benefit performance included Skint Video.
Rave and dance-music events were held in 1989 and 1990, which included Arc, Crazy Feet, Karma, Menace, Project 679 and TomTom Club.
Towering Inferno recorded their album, Kaddish, at the Diorama in 1991: "We knew we had to get a mythic, religious sound and we knew from playing there that the Diorama has a five or six second reverb."
The Manic Street Preachers played in December 1991.
The Pogues: You gotta see the Pogues', recalls Chevron. 'They are the happening band in London at the moment.' On 22 June, Elvis dutifully went along to the Diorama in Euston ..."
The London Musician's Collective operated from the Diorama at the end of the 1980s: "The organisation camped out in Simon's office in the Diorama, Regents Park, and contemplated its venue-less future. Events were organised at the Diorama, Red Rose, Air Gallery and Tom Allen Centre in Stratford, but a proper home proved hard to find."
Art
Artists who have exhibited at the Diorama include:
Rafael Klein exhibited four times as part of group shows in 1989, 1990, 1991, and 1992.
Tai-Shan Schierenberg had solo exhibitions in 1988 and 1991.
In 1990, as part of a group show, Catherine Yass exhibited Madonnas.
Lucy Jones was part of "Out of Ourselves", a 1990 group exhibition.
Phyllida Barlow curated "Three Sculptures", a 1992 group exhibition which included Up Across Around.
In 1992, Rob Ryan exhibited as one of the artists against Clause 28.
Drama, video and film
Graeae Theatre Company began using the building as rehearsal space in February 1980 before performances at the University of Guildford in May of that year and a tour of the United States shortly thereafter: Quoting: "It was going to take two or three months to get the show together. Some of the cast members were working, with full time 9 to 5 jobs, 5 days a week. Secondly, one was a full time mother and thirdly we were from various parts of Britain." Videographers and filmmakers included Gaynor O'Flynn, Richard Layzell and Katharine Meynell. In 1982, Cosey Fanni Tutti recorded "Diorama - live action by Cosey at the Diorama."
Art in Danger, in 1985 and 1986, included the Bow Gamelan Ensemble, Richard Layzell, Anne Seagrave and the Wild Wigglers. The East London Theatre Archive has CAST New Variety at the Diorama flyer images dating from 1984. A number of items on the Diorama during the 1980s and 1990s are part of the Bill Douglas Cinema Museum collection, including item numbers: 97928, 97933, 97934, 97939, 97944, 97945, 97947 and 97949 from 1982 to 1992.
The London Disabilities Forum (LDF) held their first annual general meeting at the Diorama in April 1988; that month, a cabaret (later to become the Workhorse) was launched. The LDF staged "Out of Ourselves", a visual-arts exhibition, in February 1990. In June of that year, Shape Arts staged the "No Excuses Theatre Cabaret" by a Liverpool-based company of disabled actors. Drama collective The Mombasa Roadshow drama collective performed "The White Devil" in March 1989 and "The Bacchae" in April 1990.
Other activities
The Philadelphia Association (PA) had an office and, later, a consulting room in the Diorama by 1981; the PA's Hilary Randall and Paul Zeal became directors of the DACL. Collusion magazine was based at the Diorama in 1982 and 1983. The magazine was founded by Steve Beresford, Sue Steward and David Toop in 1981, and its musical content included experimental, global, popular and world. After five issues, the magazine ceased publication in September 1983.
Performance magazine was based at the Diorama from 1982 to 1987: "Between 1979-1992 Performance Magazine documented an extraordinary period in the development of art in the UK. With its maverick and punk ethos Performance Magazine embodied an immensely active community of artists, writers and publics that crossed disciplines throughout the late 70s, 80s and the start of the 90s." The fashion company Slag had a studio at the Diorama from 1984 until its 1992 closure: "They're 25ish, have no admitted names other than Andy (him) and Adie (her) - collectively Slag ... They perch in a workroom in a run-down peculiarity of a building - the Diorama - and their place looks like a carnival novelties store, or a backstage attic prior to final closure. But then, they belong to that generation which grew up in playspace cluttered with encouragements to creativity ..."
Studio Upstairs had a studio at the Diorama from 1989: "At Studio Upstairs, people with psychiatric problems have a place to express their interests and abilities through art ... Behind its Regency facade, Diorama's interior hides a hive of activity including a cafe (The Octagon), Tai Chi classes, and musicians of all sorts". The Neo Naturists body painters presented a May Day performance at the Diorama in 1990.
References
External links
Luminous Music
PlaySpace publications
Art and design organizations
Artist cooperatives
Art therapy
Creative arts therapies
Disability culture
Electronic dance music venues
History of the London Borough of Camden
Independent magazines
Musical culture
Musical theatre organizations
Performing arts in London
Street fashion
Video art | Diorama Arts Cooperative | [
"Engineering"
] | 2,561 | [
"Design",
"Art and design organizations"
] |
70,820,459 | https://en.wikipedia.org/wiki/Photon-Induced%20Near-field%20Electron%20Microscopy | Photon-Induced Near-field Electron Microscopy (PINEM) is a variant of the Ultrafast Transmission Electron Microscopy technique and is based on the inelastic coupling between electrons and photons in presence of a surface or a nanostructure. This method allows one to investigate time-varying nanoscale electromagnetic fields in an electron microscope.
For visible light, such inelastic coupling between electrons and light, i.e. direct absorption or emission of photons, is forbidden in free space (vacuum) since it is not possible to simultaneously conserve both energy and momentum. This constraint can be circumvented when photon momentum is broadened as a result of light being reflected or scattered from a surface or nanostructure. This process would then generate evanescently confined near-fields with a broad momentum distribution, reaching high intensities in a nanoconfined space and thus also boosting the cross section of electron-light coupling.
Theoretically, the analytical description of the phenomenon has been provided by Park et al., Garcia de Abajo et al. and Feist et al. In these works the authors demonstrated that the strength of electron-light interaction depends on the linear coupling to the electric field projection along the electron propagation direction. In particular, Feist et al. also experimentally demonstrated that the interaction process results in a coherent spectral redistribution of the electron wave packet producing Rabi oscillations of a multi-level quantum ladder in which the states are separated by the photon energy.
Particularly appealing for photonics application is the fact that the spectral, spatial and momentum distributions of the electrons subjected to such inelastic scattering process are strictly correlated with the near-field distribution mediating the electron-light coupling. The latter can be thus mapped in space and time with ultrafast electron microscopy methods, providing femtosecond movies of nanoscale fields in and around nanostructures.
More interestingly, the PINEM method can also be used to dynamically manipulate the wave properties of the electron beam by using suitably prepared electromagnetic field configuration. In such a way, one can modulate coherently the amplitude and phase of the electron beam along both the longitudinal and the transverse directions.
See also
Transmission electron microscopy
Electron energy loss spectroscopy (EELS)
Energy filtered transmission electron microscopy (EFTEM)
References
Electron beam
Electron microscopy techniques
Scientific techniques
Quantum electrodynamics
Photonics | Photon-Induced Near-field Electron Microscopy | [
"Chemistry"
] | 487 | [
"Electron",
"Electron beam"
] |
70,820,827 | https://en.wikipedia.org/wiki/M9%20gun%20director | The M9 gun director was an electronic director developed by Bell Labs during World War II. This computer continuously calculated trigonometric firing solutions for anti-aircraft weapons against enemy aircraft. When cued by the SCR-584 centimetric gun-laying radar and used in concert with anti-aircraft guns firing shells with proximity fuzes, it helped form the most effective anti-aircraft weapon system utilized by the Allies during the war.
Background
During the late 1930s the United States Army's signal corps attempted to utilize the newly developed SCR-268 radar to provide fire control quality data to the Sperry Corporation's M4 mechanical gun director. The SCR-268's longwave did not provide accurate enough data for the pairing to be an effective anti-aircraft weapon. In 1940, Vannevar Bush formed the National Defense Research Committee and its section D-2 was tasked with examining issues related to fire control headed by Warren Weaver.
Development
In May 1940, an engineer at Bell named David Parkinson had a dream about being in an anti-aircraft revetment where he also spotted a potentiometer. He spent the next couple of weeks working with his boss to draft specifications for an analog computer that provided firing solutions for anti-aircraft guns. Later that year, Bell Labs, at the time led by Harvey Fletcher and Mervin Kelly, submitted a proposal to the National Defense Research Committee. Their proposed director would calculate course and speed of incoming aircraft, shell velocities and fuse timing, powder temperatures, shell drift, and air density and wind speeds to provide a predicted firing solution for the associated gun battery. The project was approved in December 1940 and the initial work on the project was completed by Drs. David B. Parkinson and Clarence A. Lovell under the direction of Dr. Edward Wente. A prototype, designated T-10, was delivered to the Army only a few days after the attack on Pearl Harbor and a few hundred sets were ordered immediately. As the SCR-584's development continued it was paired with the M9.
On November 9, 1943, a demonstration was held for senior Army leadership at the Bell Lab facility in Mullica Hill, New Jersey. Once operational testing was complete, the M9 was mass-produced at the Hawthorne Works in Cicero, Illinois.
Operational Use
90 mm anti-aircraft guns were normally operated in groups of four, utilizing the SCR-584 radar and being controlled by the M9 director. The SCR-584 was accurate to about 0.06 degrees (1 mil) and also provided automatic tracking. Direction and range information was sent directly to the M3 gun data computer, and M9 director, which directed and laid the guns automatically. All the crews had to do was load the guns.
SCR-584s with the associated M9 gun directors were rushed to the Anzio beachhead in February 1944 to assist with engaging the German-Italian air force that was jamming the SCR-268s and bombing the beachhead and harbor at night. On the evening of February 24, 1944, four American 90 mm guns opened fire on a flight of 12 Junkers Ju 88s, shooting down five of them. The success achieved that evening dramatically reduced German nighttime bombing moving forward.
In June 1944, the M9, working in concert with the SCR-584 and anti-aircraft batteries utilizing proximity fuses, formed the bulwark of defense against German V-1 flying bombs launched against southern England. Training and accuracy improved so that by the end of August, Allied crews were shooting down nearly two-thirds of incoming V-1s.
See also
Operation Diver
Citations
References
Bibliography
Web
Analog computers
Military equipment introduced from 1940 to 1944
Applications of control engineering
Artillery components
Ballistics
Anti-aircraft guns of the United States
Artillery operation | M9 gun director | [
"Physics",
"Technology",
"Engineering"
] | 775 | [
"Applied and interdisciplinary physics",
"Control engineering",
"Artillery components",
"Ballistics",
"Applications of control engineering",
"Components"
] |
70,821,169 | https://en.wikipedia.org/wiki/HD%2093521 | HD 93521 is a single, massive star in the northern constellation of Leo Minor. With an apparent visual magnitude of 7.03, it is too faint to be seen with the naked eye. The star is located at a distance of approximately from the Sun based on parallax measurements. It is positioned at a high galactic latitude of +62° and is located about above the Galactic plane.
The spectrum of this star matches an O-type main-sequence star with a stellar classification of O9.5V. It is unusual for a star of this class to have formed so far away from the galaxy's star forming regions. Absorption lines in its spectrum indicate a metallicity that is inconsistent with being a population II star, which are typically found in the galaxy halo. Likewise, HD 93521 is unlikely to be a runaway star or a hot subdwarf, either of which could explain its remote location. It may instead be a blue straggler that was formed as a result of a merger. The resulting star likely began as a close binary system of lower mass, longer-lived stars that were ejected from the galactic disk. The merger would then have reset the evolutionary clock, producing a hotter, shorter-lived star.
HD 93521 is one of the most rapidly rotating stars known, with estimates of its projected rotational velocity ranging from 390 up to 435 km/s. This is at least 90% of the star's breakup velocity, assuming it is being viewed from along the equator. The rapid spin is creating an equatorial bulge with the radius at the equator being an estimated 7.4 times the Sun's radius while the polar radius is 6.1 times that of the Sun. Due to gravity darkening, the surface temperature at the poles is while the temperature at the equator is only .
The star may be undergoing mass loss from its stellar wind and have an equatorial disk of orbiting gas. The star shows evidence of non-radial pulsations, which may be the result of a more rapidly rotating core.
The brightness, position, and rapid rotation of this star makes it particularly suited to examining the interstellar gas in the Milky Way halo.
References
Further reading
O-type main-sequence stars
Blue stragglers
Leo Minor
Durchmusterung objects
093521
052849 | HD 93521 | [
"Astronomy"
] | 468 | [
"Leo Minor",
"Constellations"
] |
70,821,684 | https://en.wikipedia.org/wiki/Alan%20Lidiard | Alan Bernard Lidiard (9 May 1928 – 21 November 2020), or A. B. Lidiard, was a British condensed matter physicist known for his research into defects in materials.
Education and career
Lidiard studied theoretical physics under Charles Coulson at King's College London, obtaining an MSc in 1950 and a PhD in 1952. He spent two years as a Fulbright scholar in the USA, first as a research assistant for Friedrich Seitz at the University of Illinois Urbana-Champaign and then under Charles Kittel at University of California, Berkeley. He took up a research fellowship in the Theoretical Division at Atomic Energy Research Establishment in Harwell. Between 1957 and 1961, he was a Lecturer in Theoretical Physics at University of Reading. He returned to Harwell and set up the radiation damage theory group in the Theoretical Physics Division (TPD). Lidiard became the head of the TPD in 1966 until his retirement. Afterwards, he moved to the Department of Physics at University of Reading and the Department of Theoretical Chemistry at Oxford University.
Honors and awards
Lidiard was awarded the Guthrie Medal in 1988. He was a Fellow of the Institute of Physics and a Fellow of the Royal Society of Chemistry.
Personal life
Lidiard married three times. He has two daughters from his second marriage.
Bibliography
See also
Marshall Stoneham
Richard Catlow
References
1928 births
2020 deaths
Alumni of King's College London
Academics of the University of Reading
British physicists
Condensed matter physicists
Academics of the University of Oxford
People from Waltham St Lawrence | Alan Lidiard | [
"Physics",
"Materials_science"
] | 306 | [
"Condensed matter physicists",
"Condensed matter physics"
] |
70,823,586 | https://en.wikipedia.org/wiki/Karen%20H.%20Johannesson | Karen H. Johannesson is an American geochemist and professor in the School for the Environment at the University of Massachusetts Boston and the Intercampus Marine Sciences Graduate Program of the University of Massachusetts System. She teaches geochemistry and has expertise in environmental geochemistry, biogeochemistry, trace element speciation, geochemical modeling, chemical hydrogeology, reaction path and reactive transport modeling.
Biography
Johannesson was born and raised in the Contoocook Valley region of New Hampshire. She received her Bachelor of Science in geology at the University of New Hampshire in 1985. Johannesson then went on to receive a master's degree in 1988 from Boston College in geology and geophysics. She then received her doctorate in hydrology and hydrogeology from the University of Nevada Reno. Johannesson has worked for four universities since receiving her PhD. She worked as an assistant professor at Old Dominion University from 1998 to 2002. After this, she worked as a professor for five years at the University of Texas at Arlington. Her longest position as a professor was at Tulane University as a Cochran Family Professor of Geochemistry and Chemical Hydrogeology, where her laboratory focused on elevated arsenic levels in the groundwater of Ganges Brahmaputra delta and fluxes of trace elements to coastal ocean through groundwater. Currently Johannesson works as a professor of geochemistry at the University of Massachusetts Boston in the School for the Environment. Her research focuses on the chemical speciation and biogeochemical cycling of trace elements in the environment.
Johannesson is the author of the book Rare Earth Elements in Groundwater Flow Systems which focuses on the geochemistry of the lanthanide series elements in groundwater environments. It was first published in 2005.
Since 2016 Johannesson has served as Co-Editor-in-Chief of the journal Chemical Geology. She has also served as an associate editor for the journal Geochimica et Cosmochimica Acta since 2005 and was an associate editor for American Mineralogist from 2014 until 2017.
Awards and honors
In 2015, Johannesson was awarded the Geochemical Society's Clair C. Patterson medal for her research in environmental geochemistry. She became a Fellow of the Geological Society of America in 2010, the International Association of Geochemistry in 2014, and the Geochemical Society as well as the European Association of Geochemistry in 2015.
Publications
Some of the more recent work that Johannesson is involved with consists of research on chemicals found in groundwater. An article she had participated in was "Chlorine-salinity as indicator of the chemical composition of groundwater: empirical predictive model based on aquifers in Southern Quebec, Canada". The research aimed to categorize the 12 chemical elements discovered in the groundwater at the location in order to create correlations between the chemicals to salinity levels. Her contribution to environmental studies has resulted in 173 current publications thus far.
References
External links
Faculty website
Year of birth missing (living people)
Living people
American geochemists
American women geologists
Scientists from New Hampshire
Women hydrologists
University of New Hampshire alumni
American hydrologists
American women chemists
University of Massachusetts Boston faculty
University of Texas at Arlington faculty
Morrissey College of Arts & Sciences alumni
Old Dominion University faculty
University of Nevada, Reno alumni
Fellows of the Geological Society of America
20th-century American geologists
American academic journal editors
20th-century American women scientists
American women editors
American editors
20th-century American chemists
21st-century American chemists
21st-century American women scientists
21st-century American geologists | Karen H. Johannesson | [
"Chemistry"
] | 711 | [
"Geochemists",
"American geochemists"
] |
70,823,668 | https://en.wikipedia.org/wiki/Microsphaeropsis%20caloplacae | Microsphaeropsis caloplacae is a species of lichenicolous (lichen-eating) fungus in the family Didymosphaeriaceae. It is only known to occur in a single locality along the Kızılırmak River in Turkey, where it grows parasitically on the crustose lichen Caloplaca persica.
Taxonomy
The fungus was formally described as a new species in 2009 by Javier Etayo and Kenan Yazıcı. The type specimen was collected by the second author along the Kızılırmak River (Sivas Province) at an altitude of ; there, the lichen was found growing on the apothecial discs of the crustose lichen Caloplaca persica, which itself was growing on the bark of a Populus tree. The species epithet refers to the genus of the host lichen, Caloplaca.
The authors noted that they placed this species provisionally into Microsphaeropsis "with some hesitation", as the species in this genus typically infect plant leaves.
Description
Microsphaeropsis caloplacae produces pycnidia that are entirely immersed in the host lichen's apothecial discs. They are apparent as barely visible blackish spots with a diameter between 30 and 50 μm, with an ostiole (opening). The pycnidial cavity is filled with conidia that measure 7.2–8.3 by 4–6 μm. Infections by this fungus do not seem to be highly pathogenic to the lichen, as the hymenium of the apothecia continues producing spores as normal.
Habitat and distribution
Microsphaeropsis caloplacae is only known from the type locality, a well-lit site with typical steppe vegetation, about from the Kızılırmak River.
References
Pleosporales
Fungi described in 2009
Fungi of Europe
Lichenicolous fungi
Taxa named by Javier Angel Etayo Salazar
Fungus species | Microsphaeropsis caloplacae | [
"Biology"
] | 424 | [
"Fungi",
"Fungus species"
] |
70,823,831 | https://en.wikipedia.org/wiki/Mevidalen | Mevidalen (LY-3154207) is a dopaminergic drug which is under development for the treatment of Lewy body disease, including those with Parkinson's disease.
It acts as a selective positive allosteric modulator (PAM) of the dopamine D1 receptor. The drug is orally active and crosses the blood–brain barrier. It is a tetrahydroisoquinoline and is a close analogue of DETQ, another D1 receptor PAM.
Mevidalen has been found to have wakefulness-promoting effects in sleep-deprived humans. Side effects of mevidalen have been reported to include increased heart rate and blood pressure, insomnia, dizziness, nausea, vomiting, anxiety, fatigue, headaches, palpitations, and contact dermatitis, as well as falls in those with dementia.
As of November 2023, mevidalen is in phase II clinical trials for the treatment of Lewy body disease. Besides for movement disorders and dementia, D1 receptor PAMs like mevidalen might have value in the treatment of certain neuropsychiatric disorders, such as depression, hypersomnolence, and attention deficit hyperactivity disorder (ADHD).
See also
Glovadalen (UCB-0022)
Razpipadon (CVL-871)
Tavapadon (CVL-751)
References
Amides
Chlorobenzene derivatives
D1-receptor agonists
Experimental drugs
Ketones
Primary alcohols
Tertiary alcohols
Tetrahydroisoquinolines
Wakefulness-promoting agents | Mevidalen | [
"Chemistry"
] | 335 | [
"Ketones",
"Amides",
"Functional groups"
] |
70,824,018 | https://en.wikipedia.org/wiki/Trazpiroben | Trazpiroben (developmental code name TAK-906) is a dopamine antagonist drug which was under development for the treatment of gastroparesis. It acts as a peripherally selective dopamine D2 and D3 receptor antagonist. The drug has been found to strongly increase prolactin levels in humans, similarly to other peripherally selective D2 receptor antagonists like domperidone. Clinical development of trazpiroben was discontinued before April 2022. Trazpiroben was originated by Altos Therapeutics and was under development by Takeda Oncology.
References
External links
Trazpiroben - AdisInsight
Abandoned drugs
D2 antagonists
D3 antagonists
Motility stimulants
Peripherally selective drugs
Prolactin releasers
Benzoic acids
Spiro compounds
Cyclohexanes
Imidazolidinones
Piperidines | Trazpiroben | [
"Chemistry"
] | 183 | [
"Organic compounds",
"Spiro compounds",
"Drug safety",
"Abandoned drugs"
] |
70,827,516 | https://en.wikipedia.org/wiki/Opegrapha%20vulpina | Opegrapha vulpina is a species of lichenicolous (lichen-eating) fungus in the family Opegraphaceae. It is found in the Czech Republic, Dobruja, Romania, and the Italian Apennine Mountains. It grows parasitically on two species of saxicolous (rock-dwelling), crustose lichens.
Taxonomy
The fungus was formally described as new in 2008 by Jan Vondrák, Jana Kocourková, and Mauro Tretiach. The type specimen was collected from the ruins of the castle in the region of Pavlov (South Moravia) at an altitude of ; there, the lichen was found growing parasitically on the thallus of the crustose lichen Caloplaca erodens, which itself was growing on west-exposed limestone. The species epithet honours Czech lichenologist Jiří Liška, friend of the authors, whose English surname means "fox" in English (= vulpes in Latin).
Description
The ascomata are apothecial in form, and usually occur as irregular dark patches on the thallus of the host lichen. They are rounded, measuring about 0.2 mm in diameter, and have a distinct carbonized (blackened) exciple (rim). The asci contains eight ascospores and are fissitunicate, meaning that they have two functional ascal wall layers and discharge of the spores involves the separation of these layers. The ascospores are shaped like narrow ellipsoids and have a transparent coat () around it, their dimensions are about 14.5 by 6 μm. They are initially hyaline, but become brownish and develop fine granular ornamentation with age. The conidiomata are black pycnidia partially immersed in the host thallus, measuring roughly 80–130 μm; the conidia they produce are narrowly ellipsoid to bacilliform in shape and measure 4.5 by 1.2 μm.
Habitat and distribution
Originally identified from specimens collected in the Czech Republic, the fungus has since been reported from Dobruja, east Romania, and the Apennine Mountains of Italy. Known hosts are Caloplaca erodens and the related species C. albopruinosa, both of which are saxicolous lichens that inhabit limestone outcrops that are exposed to the sun.
References
Opegraphaceae
Fungi described in 2008
Fungi of Europe
Fungus species
Taxa named by Jan Vondrák | Opegrapha vulpina | [
"Biology"
] | 523 | [
"Fungi",
"Fungus species"
] |
70,827,748 | https://en.wikipedia.org/wiki/Food%20psychology | Food psychology is the psychological study of how people choose the food they eat (food choice), along with food and eating behaviors. Food psychology is an applied psychology, using existing psychological methods and findings to understand food choice and eating behaviors. Factors studied by food psychology include food cravings, sensory experiences of food, perceptions of food security and food safety, price, available product information such as nutrition labeling and the purchasing environment (which may be physical or online). Food psychology also encompasses broader sociocultural factors such as cultural perspectives on food, public awareness of "what constitutes a sustainable diet", and food marketing including "food fraud" where ingredients are intentionally motivated for economic gain as opposed to nutritional value. These factors are considered to interact with each other along with an individual's history of food choices to form new food choices and eating behaviors.
The development of food choice is considered to fall into three main categories: properties of the food, individual differences and sociocultural influences. Food psychology studies psychological aspects of individual differences, although due to the interaction between factors and the variance in definitions, food psychology is often studied alongside other aspects of food choice including nutrition psychology.
, there are no specific journals for food psychology, with research being published in both nutrition and psychology journals.
Eating behaviors which are analysed by food psychology include disordered eating, behavior associated with food neophobia, and the public broadcasting/streaming of eating (mukbang). Food psychology has been studied extensively using theories of cognitive dissonance and fallacious reasoning.
COVID-19
Food psychology has been used to examine how eating behaviors have been globally affected by the COVID-19 pandemic. Changed food preferences due to COVID-19 have been found, with both beneficial and harmful effects on food choice. Studies in Spain and Saudi Arabia found a reduced consumption of processed foods and junk food, and higher rates of sustainable diets, whereas UK residents and US university students were found to have less influence in household food choice, increased snacking behaviors and generally increased consumption of junk food. 48% of residents in a UK study reported increased food intake, especially for high energy foods, and a similar percentage reported increased food cravings. Increased food stockpiling and reduced effects of familiarity on food choice were also observed.
A 2020 review found the largest effects of COVID-19 in food choice to be from lockdowns, income loss leading to reduced food security, and bereavement due to COVID-19. For example, one study in Iran found 61% of the sample population experiencing food insecurity which resulted from both economic and psychological effects.
An individual's need for closure, a psychological measure of desire for certainty, was found to predict food stockpiling and wasting of food. A study in Chile found higher anxiety as a predictor for fast food and pastry intake, suggesting that emotional eating has been amplified due to COVID-19. By comparison, a UK study found lower levels of food craving control to be the most accurate predictor of increased high energy sweet and savoury food intake, along with emotional overeating, emotional undereating, experienced satiety and enjoyment of food being found as poor predictors.
The tendency to stockpile or hoard food has also been explained using the theory of planned behavior, using data collected from Vietnam that has suggested high risk perception is correlated with food stockpiling and panic buying. The perception of lacking food was found higher scoring in US women than US men, and higher in Indian men compared to Indian women, suggesting that country of residence may be a moderator to how gender affects need for closure in food, based on household roles.
Italy
Italy has received particular academic attention during the COVID-19 pandemic for studies of food choice as the country was one of the most severely affected by COVID-19. One study found survey results that "Around 40% of the [Italian] population perceive that strengthening the immune defences through nutrition is not important to reduce the risk of coronavirus disease". Survey results suggest that cooking behaviors were increased and junk food consumption was reduced, along with raised public interest in sustainability issues including sustainable food products.
Ethnocentrism has been proposed as an explanation for the large change in food choice and eating behaviors of Italians during COVID-19.
See also
Food science
Nutrition psychology
References
Applied psychology
Food and drink
Dietetics
Eating behaviors of humans
Food science | Food psychology | [
"Biology"
] | 895 | [
"Eating behaviors",
"Behavior",
"Eating behaviors of humans",
"Human behavior"
] |
70,828,297 | https://en.wikipedia.org/wiki/Harald%20A.%20Enge | Harald Anton Enge (September 28, 1920, Fauske Municipality, Nordland, Norway – April 14, 2008, Middlesex County, Massachusetts) was a Norwegian-American experimental nuclear physicist and inventor of instrumentation used in nuclear physics. He is known for the Enge split-pole spectrograph, which became a standard instrument of nuclear physics research.
Biography
Enge completed his secondary education in 1940 in Bodø. He studied electrical engineering and received in 1947 his engineering degree from the Norwegian Institute of Technology (now part of the Norwegian University of Science and Technology). He married his first wife in 1947. From 1948 to 1955 he was a research associate and lecturer in physics at the University of Bergen. For a year and a half in 1950 and 1951, he worked at Massachusetts Institute of Technology (MIT). For four months he was supported by MIT's Foreign Students Summer Program and then was given a salaried job by William Weber Buechner (1914–1985). At MIT Enge did research in nuclear physics using a magnetic spectrograph while working with the team led by Robert J. Van de Graaff. During this time at MIT, Enge also designed his first broad-range spectrograph, which he built when he returned to the University of Bergen. In 1954 he received his doctorate from the University of Bergen. His dissertation was supervised by Bjørn Trumpy.
In the MIT physics department, Enge was an instructor from 1955 to 1956, an assistant professor from 1956 to 1959, an associate professor from 1959 to 1963, and a full professor from 1963 to 1986, when he retired as professor emeritus. He became a U.S. citizen.
He was, for many years, the director of the MIT research group started by Robert J. Van de Graaff and was an internationally recognized expert on the design of magnetic spectrometers.
In 1967 he was co-founder and chair of Deuteron Inc. He was also associated with the Deltaray Corporation (1969 to 1973) and the Gammaray Corporation (1981).
He received in 1984 the Tom W. Bonner Prize in Nuclear Physics with citation:
In 1985 he received an honorary doctorate from the University of Bergen.
His first wife died in 1988. Upon his death in 2008, he was survived by his second wife, three sons from his first marriage, seven grandchildren, and five great-grandchildren.
Selected publications
Articles
&pg=203 chapter from 2012 reprint
Books
References
External links
1920 births
2008 deaths
Norwegian University of Science and Technology alumni
University of Bergen alumni
Massachusetts Institute of Technology faculty
20th-century American physicists
21st-century American physicists
Norwegian nuclear physicists
Experimental physicists
20th-century American inventors
21st-century American inventors
Norwegian inventors
People from Nordland
People from Bodø
Norwegian emigrants to the United States | Harald A. Enge | [
"Physics"
] | 574 | [
"Experimental physics",
"Experimental physicists"
] |
70,828,361 | https://en.wikipedia.org/wiki/10%20Trianguli | 10 Trianguli (HD 14252; HR 675; 1 H. Trianguli Minus), or simply 10 Tri is a solitary star located in the northern constellation Triangulum. It is faintly visible to the naked eye as a white-hued point of light with an apparent magnitude of 5.29. Gaia DR3 parallax measurements imply a distance of 363 light-years and it is slowly receding with a heliocentric radial velocity of . At its current distance, 10 Tri's brightness is diminished by an interstellar extinction of 0.11 magnitudes and it has an absolute magnitude of −0.02.
10 Trianguli has a stellar classification of A2 V, indicating that it is an ordinary A-type main-sequence star that is generating energy via hydrogen fusion at its core. It has 2.83 times the mass of the Sun and a slightly enlarged radius 3.71 times that of the Sun. It radiates 108 times the luminosity of the Sun from its photosphere at an effective temperature of . 10 Trianguli is rather evolved for its class, having completed 92.5% of its main sequence lifetime at the age of 372 million years. It is metal enriched with an iron abundance of [Fe/H] = +0.33 or % of the Sun's and unlike most hot stars, it spins modestly with a projected rotational velocity of .
10 Trianguli has a 13th magnitude companion located 58.3" away along a position angle of 205°. It is an unrelated background star that is much more distant than 10 Trianguli. Together with ι Trianguli and 12 Trianguli, it forms part of the obsolete Triangulum Minus.
References
A-type main-sequence stars
Triangulum
Trianguli, 10
014252
010793
0675
Durchmusterung objects | 10 Trianguli | [
"Astronomy"
] | 388 | [
"Triangulum",
"Constellations"
] |
70,828,730 | https://en.wikipedia.org/wiki/Passive%20dual%20coil%20resonator | A passive dual coil resonator (pDCR) is a purely passive receive coil insert for a preclinical magnetic particle imaging (MPI) system which provides frequency-selective signal enhancement. The pDCR aims to enhance the frequency components associated with high mixing orders, which are critical to achieve a high spatial resolution.
Motivation
One of the biggest challenges in MPI is to achieve a good signal-to-noise ratio, especially for higher harmonics. The intention behind this is that as many harmonics of the induced particle signal as possible, which drop in intensity at higher frequencies and then disappear in the noise floor, should be usable for image reconstruction to reach a better spatial resolution. To enhance the harmonics at higher frequencies, one aims to increase the inductive coupling between the particles and the receive coils at higher harmonics.
Design
As the name suggests, the pDCR, which consists of two coaxial coils, is passive because it does not have a voltage source and also no electrical connection to the rest of the MPI scanner system. The pDCR represents a resonant circuit and therefore also includes a capacitor. The pDCR picks up the particles’ magnetization response mainly with its interior coil. It then sends out the received signal with its exterior coil, but enhanced in the range of its resonant frequency. This output is then picked up by the scanner’s receive coils. There will be coupling between all the different coils of the scanner and the pDCR, however, the described process will dominate. The pDCR, i.e. the resonant circuit, is tuned to a frequency near the frequency at which the harmonics of the signal disappear into the noise floor and thus serves its function as mentioned above.
References
Medical imaging
Medical technology
Medical physics
Resonators | Passive dual coil resonator | [
"Physics",
"Biology"
] | 370 | [
"Applied and interdisciplinary physics",
"Medical physics",
"Medical technology"
] |
70,830,453 | https://en.wikipedia.org/wiki/Tautomycetin | Tautomycetin is a natural product first isolated from Streptomyces griseochromogenes, a bacterium found in the soil of the Zhejiang Province, China. It was also later found in Penicillium urticae. It is a linear polyketide very similar in structure to tautomycin, both of which contain a unique dialkylmaleic anhydride moiety, which is essential for their pharmacological activity. Tautomycetin is a selective inhibitor of protein phosphatase 1.
Biosynthesis
Much of the biosynthesis of tautomycetin has been deduced. It is synthesized in S. griseochromogenes by two type I polyketide synthases, denoted by modules named TtnA and TtnB. After initial loading with acetyl-CoA, four methylmalonyl-CoAs and three malonyl-CoAs are added alternately by sequential Claisen condensation, followed by one ethylmalonyl-CoA. Each ketone of the incorporated acetate group is selectively modified by a ketoreductase (KR), dehydratase (DH), or enoylreductase (ER) as indicated. The dialkyl maleic anhydride moeity is synthesized separately by eight enzymes (TtnKLMNOPRS) and incorporated into the growing polyketide by esterification mediated via TtnK at the end of TtnA. The polyketide is released from TtnB, by a thioesterase TtnB-TE and undergoes oxidation at the C6 position, catalyzed by the enzyme TtnI. Finally, this intermediate undergoes an enzyme-catalyzed decarboxylation-dehydration to form the final compound, tautomycetin.
The total synthesis of tautomycetin has been reported.
Pharmacology
Tautomycetin has been shown to have antibiotic and antifungal activities. It has also been identified as a potent protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A) inhibitor with IC50 values as low as 0.21 nM and 0.94 nM respectively, the lowest of over 40 natural product phosphatase inhibitors. In addition, tautomycetin is a potent T cell-specific immunosuppressor and has been investigated for treatment in grafting and transplantation. It has useful anticancer properties, inducing apoptosis through the inhibition of several protein cascades in colorectal cancer and thyroid cancer.
References
Polyketides
Polyketide antibiotics
Carboxylic anhydrides | Tautomycetin | [
"Chemistry"
] | 561 | [
"Biomolecules by chemical classification",
"Natural products",
"Polyketides"
] |
70,831,190 | https://en.wikipedia.org/wiki/Psi%20Octantis | Psi Octantis, Latinized from ψ Octantis, is a solitary star in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.47, allowing it to be seen with the naked eye under ideal conditions. The star is relatively close at a distance of 126 light years but is receding with a heliocentric radial velocity of .
Psi Octantis has a spectral classification of F0IIp, suggesting that it is a bright giant but with peculiarities. Other assessments give a luminosity class of III (giant), III-IV (intermediate between giant and subgiant), or V: (approximately main sequence). One paper gives a spectral class of F4V:kA5, indicating that it is a probable F-type main-sequence star with the calcium K-lines of an A5 star, including sharp absorption lines of metals. Analysis of its evolutionary stage show it to be a somewhat evolved main sequence star.
It has 149% the mass of the Sun and 1.74 times the radius of the Sun. It shines at 7.82 times the luminosity of the Sun from its photosphere at an effective temperature of 7,244 K, giving it a yellowish white glow. Psi Octantis has an iron abundance 91% that of the Sun and is estimated to be 1.41 billion years old.
References
Octans
F-type bright giants
210853
110078
8471
Octantis, 60
Octantis, Psi
PD-78 1442 | Psi Octantis | [
"Astronomy"
] | 317 | [
"Octans",
"Constellations"
] |
70,831,420 | https://en.wikipedia.org/wiki/Electroplasticity | Electroplasticity, describes the enhanced plastic behavior of a solid material under the application of an electric field. This electric field could be internal, resulting in current flow in conducting materials, or external. The effect of electric field on mechanical properties ranges from simply enhancing existing plasticity, such as reducing the flow stress in already ductile metals, to promoting plasticity in otherwise brittle ceramics. The exact mechanisms that control electroplasticity vary based on the material and the exact conditions (e.g., temperature, strain rate, grain size, etc.). Enhancing the plasticity of materials is of great practical interest as plastic deformation provides an efficient way of transforming raw materials into final products. The use of electroplasticity to improve processing of materials is known as electrically assisted manufacturing.
History
Electroplasticity was first discovered by Eugene S. Machlin, who reported in 1959 that applying an electric field made NaCl weaker and more ductile. Since then, the effect of electric fields on plasticity has been studied in many materials systems including metal, ceramics, and semiconductors. Various mechanisms have been posited to explain electroplastic effects and their dependence on materials properties and external conditions. For most materials the electroplastic effect arises from a combination of multiple mechanisms. This should not be all that surprising given that the electric fields directly affect electrons which dictate the bonding in materials and therefore all higher level phenomena such as dislocation motion, flow stress, vacancy diffusion, etc.
Electroplasticity in Metals
The application of DC electric fields is known to reduce the flow stress of metals and metal alloys while increasing the fracture strain. Several mechanisms have been put forth to explain this effect including Joule heating, electron wind force, dissolution of metallic bonds, and unpinning of dislocations due the induction of magnetic fields. None of these mechanisms on their own can sufficiently explain the full extent of electroplasticity in metals. The application of electric fields has been shown to enhance the effect of superplasticity which occurs in polycrystalline metals at high homologous temperatures (T>0.5Tm). This is likely due to the electric field reducing cavitation, which can lead to premature fracture, and grain growth, which can prevent superplastic flow due to grain boundary sliding, in addition to reducing the activation energy for grain boundary sliding. The strength of the electroplastic effect scales with the magnitude of the applied electric field past some threshold value. While the application of an electric field typically augments the plasticity of metals there are alloy systems that show a reduction in plasticity. Conrad and Li found that the activation energy for grain boundary sliding in Zn-5 wt.% Al increased by nearly 20% under the application of a 2 kV cm^{-1} DC electric field, resulting in more difficult deformation.
Electroplasticity in Ceramics
The application of electric fields to ceramics can give rise to plasticity in materials that traditionally exhibit no plastic deformation. High homologous temperatures are, however, typically necessary to achieve significant plastic deformation in ceramic materials. Plastic deformation ceramic oxides was found by Conrad et al. to occur under relatively modest electric field strengths (0.02-0.32 kV cm^{-1}). Strain-mediating defects such as vacancies and dislocations tend to be charged in ceramic materials due to the ionic or covalent nature of bonding. Thus, the movement of electrons can have a direct impact on the mobility of these defects in ceramics and subsequent plastic deformation. The primary effect of the electric field in the deformation of fine-grained ceramic oxides is to shift the diffusion pathway from bulk diffusion to grain boundary diffusion, resulting in greater diffusion and easier grain boundary sliding.
References
Electrochemistry
Materials science | Electroplasticity | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 773 | [
"Electrochemistry",
"Applied and interdisciplinary physics",
"Materials science",
"nan"
] |
70,832,489 | https://en.wikipedia.org/wiki/Space%20sexology | Space sexology has been defined as the "comprehensive scientific study of extraterrestrial intimacy and sexuality". It aims to holistically understand intimacy and sexuality in space, including its risks, and potential benefits for the health and well-being of those who travel beyond our home planet.
History
Spokespeople for space organizations, such as NASA, have historically gone on record expressing that they do not study sexuality in space. In fact, Bill Jeffs, the spokesperson for NASA's Johnson Space Center, has stated that: "We don't study sexuality in space, and we don't have any studies ongoing with that. If that's [your] specific topic, there's nothing to discuss". Some researchers and scientists have argued that decisions made by space organizations are often heavily influenced by the sociocultural norms of their benefactors. As such, they posit that sexually conservative ideologies may hinder furthering the study of space sexology. Given the persistent lack of research on human sexuality and intimacy in space, scientists and researchers have called for studies in this area for decades.
In 1989, Roy Levin wrote the first paper exploring the potential effects of space travel on human sexuality and the human reproductive system, and called attention to the lack of research in this area.
In 1998, Ray Noonan wrote the first philosophical inquiry on human intimacy and sexuality for extended spaceflights. In his doctoral thesis, Noonan discussed possible sexological challenges faced by astronauts on long-duration missions and related implications for mission success. Expanding on his own work, Noonan proposed in 2001 that space agencies should collaborate with scientific communities to form programs to study sex in space.
In 2005, Shimizu and colleagues echoed this belief, arguing that human sexuality research was crucial in order to successfully envision a future in space.
In her 2016 book titled "Sex in Space", Laura Woodmansee explored questions relating to interstellar intercourse, from sexual mechanics, to conception, pregnancy, and birth in low gravity situations. She further emphasized the need for extraterrestrial sex research. That same year, Alexander Layendecker shed light on the absence of human sex research conducted by the NASA. He further advocated for the development of an Astrosexological Research Institute. Layendecker raised important questions regarding the possible effects of space conditions (e.g., exposure, radiation, microgravity, etc.) on phenomena such as conception, pregnancy, and child development.
In 2018, Alexander Layendecker and Shawna Pandya co-wrote "Logistics of Reproduction in Space". In it, they present the body of research that has been produced on topics of human sexuality, reproduction and development in space. They also explored some of the logistical challenges associated with these topics. However, they concluded that the current literature on such topics remains scarce, and that there is not enough data to assert whether conception, gestation, and development can safely (or successfully) occur in space.
Most recently, in 2021, Dubé and colleagues highlighted the importance of considering space sexology as a scientific field and research program. Noting a significant lack of research related to space intimacy and sexuality, their article titled "The Case for Space Sexology" explores the risks and benefits of studying these basic human needs in an extraterrestrial context. They posit that the use of a biopsychosocial framework could expedite and improve research among space organizations while contributing to the health and well-being of future space inhabitants. Since the publication, the authors have commented on the growth of support among the research community and space sector for the advancement of space sexology. For example, Maria Santaguida, co-author of the article, stated in an interview with Mic that: "More and more researchers around the globe and people working in the space sector recognize that addressing human intimate and sexual needs in space is one of the keys to unlocking our long-term expansion into the universe".
It has been argued that NASA's rigid stance on sexuality in space may be softening. When asked to comment on Dubé and colleagues' "The Case for Space Sexology" by a MIC journalist, a NASA representative stated that "Should a future need for more in-depth study on reproductive health in space be identified, NASA would take the appropriate steps." In contrast with NASA's historically blunt rejections of proposals regarding sex and space, this response has been interpreted as a signal of change – one which may open the door for future exploration of human sexuality in space.
Anticipated risks and benefits of sexuality in space
Dubé et al. (2021) proposed that space organizations should embrace the discipline of space sexology to enhance the benefits and mitigate the risks of human sexuality and intimacy in space. The researchers described risks associated with the physical and chemical properties of space environments, such as the effects of ionizing radiation and gravitational changes on fertility, conception, pregnancy and fetal/child development. Other risks are related to the intimacy and needs of space-travelers, such as the limited privacy on spacecraft, hygienic concerns, long-term isolation and mental health repercussions arising from lack of sexual fulfilment. Dubé and colleagues (2021) also expressed concern over the potential sexual violence and harassment as these acts have already occurred in space simulation contexts. This concern was reiterated by Santaguida and colleagues (2022) who argued that it is “time to plan for #MeToo in space.” For example, Judith Lapierre, co-author of the article, experienced sexual harassment on a 110-day experiment on a Mir Space Station replica. Less than a month into the experiment, Lapierre was non-consensually grabbed and kissed by a Russian crew member who oversaw the mission. She was also subjected to other forms of sexist behaviors by her male colleagues. While discussing these events in another publication, Lapierre stated: "It is time, more than ever, to meet the real challenges of space exploration, with honesty, transparency, and by recognizing that Earth's unacceptable behaviors are also Space's unacceptable behaviors for a spacefaring civilization".
Dubé and colleagues (2021) identified some of the benefits that could accompany studying sex in space. Such benefits directly impact the health and well-being of astronauts, an idea supported by an extensive body of research conducted on the positive benefits of sex on both physiological and psychological aspects of human functioning. Physiologically, sex can have a positive impact on stress levels, blood pressure, sleep, immune functioning and cardiovascular health. Psychologically, sex is important in maintaining a positive self-esteem and body image, and masturbation (a practical and accessible practice) has been shown to be particularly healthy and important in relieving sexual tension and stress.
Potential solutions to the challenges of space sexology
Despite intimacy and sexuality becoming increasingly recognized as a fundamental human right, space organizations have historically evaded sex-related research.Researchers have speculated that these organizations tend to avoid controversies that could result in reduced funding. Dubé et al. (2021) proposed that space organizations should be reminded of the risks of limiting sex and intimacy in space while highlighting the potential benefits of enabling them as a possible solution. They argue that organizations are ultimately responsible for the health and well-being of their astronauts and as such, intimate and sexual needs ought not be overlooked. To better meet the needs of their space travellers, they state that space organizations may want to adopt a progressive, sex-positive agenda that values sexual rights. They suggested that emphasizing the importance of intimacy and sex in space could in turn help investors and the public view this discipline as valuable and necessary.
Dubé and colleagues (2021) proposed that technological systems and guidelines enabling intimacy and sexuality in the limiting artificial ecosystems of space will need to be created. They describe that these systems and guidelines will likely need to be designed to be both safe and hygienic, similar to the already established systems in place for other basic needs such as eating and grooming. They also suggest that this challenge can be addressed by space organizations by considering the use of sexual technology adapted for space to meet the intimate needs of their astronauts, such as erotic stimuli, sex toys, and artificial erotic agents (e.g., virtual partners, erotic chatbots, and sex robots).
Dubé and colleagues (2021) indicate that successfully researching space sexology will likely require cooperation and contributions from both space organizations and their astronauts. They acknowledge that this may prove challenging, as conflicting sexual views between administrators and astronauts alike could complicate group cohesion. To facilitate an inclusive understanding of the value of extraterrestrial sex and intimacy, Dubé and colleagues (2021) recommend that space organizations invest in training programs that encapsulate the complexity of human intimacy and sexuality. Such programs could aim to foster sex-positive ethics among space organizations and their respective personnel.
See also
Sex in space
Space tourism
Space medicine
Space colonization
Space advocacy
Effect of spaceflight on the human body
References
External links
Human sexuality
Human spaceflight
Sexology | Space sexology | [
"Biology"
] | 1,838 | [
"Human sexuality",
"Behavior",
"Human behavior",
"Sexology",
"Behavioural sciences",
"Sexuality"
] |
58,435,848 | https://en.wikipedia.org/wiki/Barrier%20certificate | A barrier certificate or barrier function is used to prove that a given region is forward invariant for a given ordinary differential equation or hybrid dynamical system. That is, a barrier function can be used to show that if a solution starts in a given set, then it cannot leave that set.
Showing that a set is forward invariant is an aspect of safety, which is the property where a system is guaranteed to avoid obstacles specified as an unsafe set.
Barrier certificates play the analogical role for safety to the role of Lyapunov functions for stability. For every ordinary differential equation that robustly fulfills a safety property of a certain type there is a corresponding barrier certificate.
History
The first result in the field of barrier certificates was the Nagumo theorem by Mitio Nagumo in 1942. The term "barrier certificate" was introduced later based on similar concept in convex optimization called barrier functions.
Barrier certificates were generalized to hybrid systems in 2004 by Stephen Prajna and Ali Jadbabaie.
Variants
There are several different types of barrier functions. One distinguishing factor is the behavior of the barrier function at the boundary of the forward invariant set . A barrier function that goes to zero as the input approaches the boundary of is called a zeroing barrier function. A barrier function that goes to infinity as the inputs approach the boundary of are called reciprocal barrier functions. Here, "reciprocal" refers to the fact that a reciprocal barrier functions can be defined as the multiplicative inverse of a zeroing barrier function.
References
Differential equations | Barrier certificate | [
"Mathematics"
] | 305 | [
"Mathematical objects",
"Differential equations",
"Equations"
] |
58,435,980 | https://en.wikipedia.org/wiki/Clara%20Benson | Clara Cynthia Benson (1875–1964) was a Canadian chemist, the sole female founder of the American Society for Biological Chemistry (now the American Society for Biochemistry and Molecular Biology (ASBMB)) and one of the first two women to earn a Ph.D. from the University of Toronto (U of T) (the other being philosophy student Emma Baker). She later became one of U of T's first two female associate professors. Trained in physical chemistry, she switched focus to biochemistry when lack of job opportunities for female chemists led her to take a position teaching food chemistry as part of U of T's Domestic Science program. She also played a large role in the development of U of T's women's athletics program.
Early life and education
Clara Cynthia Benson was born in Port Hope, Ontario, Canada June 5, 1875 to Thomas Moore Benson and Laura Abigail Fuller. Laura and Thomas, a widowed businessman, lawyer, and judge, had three children together and additionally raised two daughters from Thomas' first marriage. Clara attended Port Hope High School then entered University College of the University of Toronto (U of T) in 1895 to study chemistry, mathematics and physics. This was only one year after the school began admitting women, and women were still not allowed into the school's reading rooms and were denied access to the library catalogues.
Benson graduated with a Bachelor of Arts in chemistry from U of T in 1899 (the first woman to do so) and continued straight into PhD studies. She earned her doctorate in 1903, making her one of the first two women to earn a Ph.D. from the University of Toronto (U of T) (the other being philosophy student Emma Baker).
Benson's doctoral research, supervised by William Lash Miller, examined reaction rates of inorganic salt solutions. Her thesis, The rates of the reactions in solutions containing ferrous sulphate, potassium iodide, and chromic acid was published in the Journal of Physical Chemistry (JPC) in May, 1903.
Career and research
Benson's early research was in the field of physical chemistry, with an emphasis on reaction rates of inorganic salt solutions. Her 1902 article "The Rate of Oxidation of Ferrous Salts by Chromic Acid" may make her the second female author (after Marie Curie) to publish in the Journal of Physical Chemistry (JPC).
As a woman, she had difficulty finding a job as a physical chemist after graduating, so she took a position as a demonstrator in food science at U of T's new Lillian Massey School of Domestic Science. She objected to this program's goal of preparing women to be housewives and had even signed a petition organized by University College's Women's Alumnae Association in 1902 questioning the program's introduction. At the time, however, food chemistry was one of the chemistry sub-fields with better professional opportunities for women.
This position involved switching from U of T's Chemistry Department to their Physiology (Physiological Chemistry) Department, where she was mentored by the "Father of the Medical School at Toronto," A.B. Macallum. Her subsequent research included biochemical examinations of fluid and tissue composition.
When food science was incorporated into U of T's medical curriculum in 1905, Benson was promoted to lecturer in physiological chemistry (biochemistry), making her the first woman at U of T to achieve a rank above demonstrator. In 1906, a royal commission report led to the creation of the Faculty of Household Science, of which Benson and the principal, Annie Laird, became associate professors, making them U of T's first female professors. Benson helped develop the school's food chemistry program and, in 1926, was promoted to full professor and head of the Department of Food Chemistry (a position she held until her retirement as professor emeritus in 1945).
Starting in 1915, she conducted summer studies at St. Andrews Biological Station examining the chemistry of seafood. At the request of Canada's Ministry of Marine and Fisheries, which was trying to build consumer demand for fish, she organized a group of food scientists from Canadian universities to work to improve fish preparation methods.
During World War I she developed and organized a course of instruction on ways to adapt food chemistry analysis techniques to explosives. These methods were adopted by munitions laboratories, helping standardized their production steps.
She was sole female founder of the American Society for Biological Chemistry (now the American Society for Biochemistry and Molecular Biology (ASBMB)) when it formed in December, 1906.
Other interests and later life
Benson advocated for the development of women's athletics at the University of Toronto, co-chairing a committee on the matter and serving as the first president of the Women's Athletic Association from 1921 until her retirement. She sat on a committee of female faculty members formed in 1928 to fight for the creation of a women's athletic facility. When U of T opened their first women's gymnasium in 1959, they named it the Benson Building in her honor.
Benson served on the national board of the YWCA (Young Women's Christian Association), chairing their Foreign Committee, and her work with the organization led her to sponsor two French World War II orphans after her retirement. Her hobbies included stamp-collecting and traveling. She also enjoyed film-making, and videos she took while on some of her travels are housed at U of T's archives.
She was colleagues and friends with biochemist Maud Menten, who was also trained by Archibald Macallum.
Benson never married nor had children, and after retiring in 1945, she returned to Port Hope where she died March 24, 1964 (aged 89).
Honors and awards
Benson was elected a fellow of the Canadian Institute of Chemistry in 1919, but was not allowed to attend their Annual Dinner in 1920 because she was a woman.
She was listed in the 1920s' American Men in Science.
U of T's Household Science alumnae created a fellowship in her honor in 1950 and hung a portrait of her by Yousef Karsh in the Household Science building.
In 1992, the Canadian Society of Chemistry created the annually-awarded Clara Benson Award to honor female chemists working in Canada.
In 2003, U of T celebrated the 100 year anniversary of her PhD achievement with a day of celebrations including a reenactment of her thesis defense.
Selected publications
References
External links
Clara Cynthia Benson archival papers held at the University of Toronto Archives and Records Management Services
20th-century Canadian women scientists
Canadian biochemists
Women biochemists
Canadian women chemists
Canadian women biologists
20th-century Canadian chemists
20th-century Canadian biologists | Clara Benson | [
"Chemistry"
] | 1,344 | [
"Biochemists",
"Women biochemists"
] |
58,436,403 | https://en.wikipedia.org/wiki/Accessory%20to%20War | Accessory to War: The Unspoken Alliance Between Astrophysics and the Military is the fifteenth book by American astrophysicist and science communicator Neil deGrasse Tyson which he co-wrote with researcher and writer Avis Lang. It was released on September 11, 2018 by W. W. Norton & Company. The book chronicles war and the use of space as a weapon going as far back as before the Ancient Greeks, and includes examples such as Christopher Columbus' use of his knowledge of a lunar eclipse and the use of satellite intelligence by the United States during the Gulf War. While speaking on the book, Tyson told National Geographic that he regards the collaboration between science and the military as a "two-way street."
Marcelo Gleiser wrote that the book "rings like a wake-up call, even if an uncomfortable one."
References
Further reading
The long entanglement of war and astrophysics - Sharon Weinberger, nature.com
Neil deGrasse Tyson on ‘Accessory to War’ and the ‘moon situation’ - Brian McElhiney, stripes.com
Neil deGrasse Tyson on the Surprising Alliance Between Astrophysicists and the Military - John Ismay, The New York Times
Books by Neil deGrasse Tyson
Astronomy books
Cosmology books
2018 non-fiction books
Popular physics books
W. W. Norton & Company books | Accessory to War | [
"Astronomy"
] | 275 | [
"Astronomy books",
"Astronomy book stubs",
"Works about astronomy",
"Astronomy stubs"
] |
58,436,733 | https://en.wikipedia.org/wiki/Alicia%20Boler%20Davis | Alicia Boler Davis is an American engineer and businesswoman. Boler Davis began her career at General Motors, rising to the rank of executive vice president of global manufacturing in 2016. In 2019, she joined Amazon as senior vice president of global customer fulfillment. During her time at Amazon, she led much of the company's response to the COVID-19 pandemic and became the first Black executive to join its senior leadership (known internally as the S-team).
In late June 2022, Davis announced she would become the new CEO of Alto Pharmacy, a digital pharmacy startup with about $1 billion in revenue and 1,200 employees, starting in September 2022.
Early life and education
Boler Davis spent her childhood fixing broken items in her home, where she grew up with her mother Denise and 3 siblings. She attended a high school program at the General Motors Institute and she decided she wanted to work there. She completed her bachelor's degree in chemical engineering at Northwestern University. She was the first generation of her family to attend college, following her sister Kimberly Boler who studied at Harvard University and became an attorney. She followed this with a master's degree in engineering science at Rensselaer Polytechnic Institute. She received a Master of Business Administration from Kelley School of Business at Indiana University Bloomington.
Career
In 1994 Boler Davis joined General Motors as a manufacturing engineer. She was plant manager at the Michigan Orion Assembly facility. She was the first black woman to become a plant manager. She simultaneously led the plant at Pontiac Stamping.
She was appointed Vice President of Customer Experience at General Motors in 2012. She was promoted to Senior Vice President for Global Customer Experience in 2013. She was part of the Forbes Most Powerful Women Next Gen Summit in 2014. That year she spoke at the University of California, Berkeley Haas School of Business. She was promoted to Executive Vice President of global manufacturing in 2016 and leads 180,000 employees. Since 2016 she has served on the board of directors at General Mills. She joined the board of Beaumont Health in 2017.
In 2018 Boler Davis became the sixth woman to be named Black Engineer of the Year. She has championed and mentored women in the automotive industry, and serves as the Executive Liaison for the GM WOMEN leadership board.
On April 1, 2019, Boler Davis Joined Amazon as VP of Global Customer Fulfillment and was subsequently promoted to SVP of Global Customer Fulfillment. Her role included leading fulfillment, customer service, and robotics globally. She quickly became one of Amazon's most high-profile executives, especially in leading much of the response to the COVID-19 pandemic, including doubling the fulfillment network, overhauling more than 150 warehouses, and hiring 275,000 people.
In June 2022, Boler Davis was named CEO of Alto Pharmacy, a digital pharmacy startup with about $1 billion in revenue and 1,200 employees. Boler Davis turned down offers to run Fortune 500 companies to lead the digital telehealth startup seeking to improve prescription delivery access.
Boards
2016 - 2019 General Mills
2017 - 2019 Beaumont Health
2023 - pres. JPMorgan Chase & Co.
Awards and honors
2021: Fortune Most Powerful Women, #17
2020: Fortune Most Powerful Women, #12
2018: US Black Engineer Magazine - Black Engineer of the Year
2018: Business Insider - Most Powerful Female Engineers in the World
2017: Automotive News - All Star in Manufacturing
2016: Trumpet Awards - Corporate Executive of the Year
2014: Women of Color Magazine - Technologist of the Year
2013: Fortune - Top 10 most powerful women in the automotive industry
2011: Michigan Chronicle - Woman of Excellence
2010: Automotive News - 100 Leading Women in the North American Automotive Industry
References
Year of birth missing (living people)
Living people
21st-century African-American people
Automotive engineers
African-American engineers
American automotive engineers
Northwestern University alumni
Rensselaer Polytechnic Institute alumni
Kelley School of Business alumni
General Motors executives | Alicia Boler Davis | [
"Engineering"
] | 789 | [
"Automotive engineering",
"Automotive engineers"
] |
58,437,070 | https://en.wikipedia.org/wiki/Participatory%20surveillance | Participatory surveillance is community-based monitoring of other individuals. This term can be applied to both digital media studies and ecological field studies. In the realm of media studies, it refers to how users surveil each other using the internet. Through the use of social media, search engines, people search sites and other web-based aggregators of data, one has the power to find information about the individual being searched, whether voluntarily shared by them or not. Issues of privacy emerge within this sphere of participatory surveillance, predominantly focused on how much information is available on the web that an individual does not consent to. More so, disease outbreak researchers can study social-media based patterns to decrease the time it takes to detect an outbreak, an emerging field of study called infodemiology. Within the realm of ecological fieldwork, participatory surveillance is used as an overarching term for the method in which indigenous and rural communities are used to gain greater accessibility to causes of disease outbreak. By using these communities, disease outbreak can be spotted earlier than through traditional means or healthcare institutions.
History
Towards the beginning of the development of Web 2.0, an increase in online socializing and interaction emerged, largely from the function of social media platforms. Social media platforms originally emerged within the context of the online information highway, where users can control what information is available to other users of the platform. Users can now digitally attach people to locations, without having to physically be within the location, a concept coined as geotagging. With added awareness of the locations of users, an aspect of greater socialization and interconnectivity emerges within both the digital and tangible world. Since the online information highway collects and stores information more permanently than the physical world, many interactions amongst online users can last much longer than physical ones. Since users can control the information and locations in which they associate themselves, they can in part surveil themselves and others to an extent. This is participatory surveillance within a web-based paradigm.
In addition to this, participatory surveillance has begun to be referred to as a tool for ecological field research. Currently, it is extremely difficult to detect disease outbreaks in enough time to prepare people for the outcomes. Often, in hard to reach areas such as the Arctic, researchers cannot gain an intensive look into the subject of disease outbreak closely enough to gain accurate results. Indigenous peoples know the ecology of the land better and how to reach overlooked locations of research. Researchers can use these people as rural surveyors, capturing instances of disease outbreak much quicker and easier than the researchers themselves.
Social media
Counter-surveillance
Counter-surveillance refers to surveillance-based challenges to power imbalances between individuals and institutions. Although state and industry mass surveillance has received substantial public attention in the wake of disclosures like those made by Edward Snowden about the National Security Agency, interest in activist-deployed and peer surveillance has been increasing. Whereas the average person may not fully understand the surveillance programs of larger collectivities, people are drawing upon surveillance tools themselves in interpersonal relationships and in attempts to bring about institutional accountability. Some researchers assert that by using these technologies of surveillance, the same ones used by companies to track consumer tendencies, the public is essentially feeding into practices of their own personal surveillance.
Empowerment
One argument towards social media based participatory surveillance is participatory surveillance within social digital media schemas work to emphasize the power that comes from monitoring what is surveilled of themselves in the context of others rather than being constituted as an invasion of privacy, or disempowerment. Within the visual discourse of reality television, the artistic narrative associated with presenting lives, creates a fake reality in which people can contextualize, therefore keeping the reality of some aspects of an individual or collectives' lives still privatized. This thinking can be transposed to other socially constructed media technologies. In contrast, ambient awareness is associated with cell phones since they are rarely turned off. This poses a greater security risk. Surveillance webcams focus on the aspects of what real users want to show to the digital audience. It is privatized in the respect that users control what they allow others to see causing them to feel liberated.
Infodemiology
An emerging term within social media based participatory surveillance, infodemiology refers to the use of digital based applications or surveys, to better track disease patterns. Information people search for related to health as well as what the public says on digital-based platforms makes up the fabric of this field of study. Coming about in 2002, infodemiology measures common social media platforms, disease and illness related websites, search engine information, and any other online user-related health data. Crowdsourcing based health-related sites have also been gaining traction in infodemiology. Some include Flu Near You, Influenza.net, Guardians of Health, AfyaData, FluTracking, Vigilant-e, and Saúde na Copa. These sites usually gather information through mapping similar symptoms of users. Some sites, such as InfluenzaNet, provide incentives for users to continue tracking their symptoms or encourage their friends to start tracking theirs.
H1N1 virus
Twitter, a user-generated platform for social media, can effectively help track users’ thoughts and opinions on diseases as well as help track disease at a greater rate. For example, the H1N1 virus (swine flu) outbreak in 2009 was analyzed through Twitter reactions and responses in order to investigate these areas of thought. After analyzing and comparing tweets through different severities of the H1N1 outbreak, the researchers posited that tweets can be a reliable estimate in understanding disease patterns.
The speed at which social media reveals public thought and trends is about two weeks faster than that of standardized disease surveillance through the proper health-related institutions. An example of social media reactions related to the H1N1 virus include an increased lack of discussion around antiviral drugs at approximately the same time as the H1N1 virus became less prevalent. However, due to the nature of social media as user-generated and unregulated, deciphering between what is relevant versus irrelevant material can blur generalizations and facts. Along with this, people are wavering and unreliable with when and what they post about on social media. With that, social media is an unstable variable which, in order to become standardized, would require great expense to create measures in which it would become feasible to make valid generalizations about. To elaborate using the example of Twitter, information on sickness can change meaning in a connotative sense. For example, if a user tweets about popular pop artist Justin Bieber saying they have “Bieber Fever,” this is very apparently not a real sickness, but a faux sickness based on the popularity of an artist. This creates issues in organizing information, requiring complex algorithms that can analyze the contours of these social meanings. Nonetheless, a recent study noted that studies focusing on the use of Youtube to detect outbreaks only had a twenty to thirty percent range of error, leading researchers' to continue looking into the prospect of social media as a force for change in disease outbreak.
Chikungunya virus
Chikungunya virus, associated with moderate to severe skin rashes and joint pain, spread to Italy at the beginning of 2007. The outbreak caused great social concern, therefore causing a plethora of social media reactions to emerge. Using an infodemiological approach, the sites where the outbreak was recorded, specifically PubMed, Twitter, Google Trends and News, and Wikipedia views and edits all provided information into when the disease was received, the concerns associated with the outbreak, and popular opinion on the disease. Interestingly, most of the Twitter posts related to Chikungunya were highly guided by search engine queries rather than empirical investigations, leading to non-usable data. Using mediation technology, Wikipedia proved to be ineffective in determining whether the site was helpful in understanding the outbreak. Moreover, users who gained opinions on the outbreak from news sources were similar to the Wikipedia edits and reactions. Similarly, the PubMed responses were consistent with that of the Wikipedia and Twitter responses. Overall, a significant amount of information was gathered from these sources, deeming these sites to be useful in documenting disease and public reaction.
Ecological field work
Cholera outbreak
In hard to access regions such as the Arctic and rural Canada, researching ecological processes and disease spread can be difficult without constant monitoring. Indigenous populations have become a key aspect in understanding the spread of disease, due to their proximity and connection to the land. For example, the Inuit populations' observations during the outbreak of avian cholera helped identify specific zones of infection in Arctic Canada. Specifically, the Common Eider, a species of sea duck, was being tracked to understand an increase in mortality from the disease. The Inuit were the first to report the increase in deaths, due to their reliance on Common Eider for meat, feathers, and eggs. With support from the Cape Dorset, Iqaluit, Aupaluk, Kangirsuk, Kangiqsujuaq, and Ivujivik Inuit communities, the researchers were able to detect the outbreak of avian cholera in thirteen locations from 2004 to 2016. The Inuit peoples were able to keep a closer eye on death rates of the Common Eider due to their daily routines and subsistence on the duck.
Privacy concerns
As digital technology advances with many dangers associated to privacy, individuals are attempting to be more accountable when meeting others. Background check websites and search engine sources reveal just how many people attempt to find information on another person, whatever the reason. Many researchers altogether ignore the idea of privacy when analyzing methods of participatory surveillance. More so, from a social media perspective, some researchers claim that by openly sharing information with others, this cannot be deemed a breach of privacy. However, a few researchers on the topic mention breaches of privacy within the spheres of both digital media studies and infodemiology.
Infodemiology
Infodemiology relies on users' information to analyze health patterns and public health concerns. However, the legality behind using other people's information without their consent can cause serious ethical privacy violations. However, limitations such as individual privacy concerns and unreliable information cause participatory digital information to sometimes be inaccurate and hard to differentiate from truth.
Doxing
Doxing is a form of cyberbullying, using the Internet to post private information about an individual or organization as a means of attack against the entity. Common information that can be leaked can be anything from a past indiscretion, home address, or even social security number of the victim. This information could be freely available on the internet for the attacker to access and further publicize. This differentiates it from other types of information leaks, since the information is simply being brought to the forefront of the public's awareness. In other words, the public information being leaked could be found freely by other parties even if it was not exposed in a more public light. The term "doxing" comes from the origins of document, first used in 2001 with the infamous hacker collective called Anonymous.
With today's current laws, most legislation pertaining to cyber threats and attacks are rooted in the 1990s, when the Internet was just developing. Due to information being stored online, doxing does not adhere to standard rights of privacy, and may be a breach of legal purpose limitation principles — data posted online may not be freely used for any purpose, even if it is publicly available, and consent cannot be assumed.
From the US constitutional perspective, individuals should have the right to disclose or not disclose information, while at the same time being able to make decisions about privacy. The US First Amendment protects the right to free speech, but doxing uniquely uses information available to the public, leading some 'doxers' to claim that they are simply exercising their First Amendment rights. The only exception to First Amendment rights came about from Cohen v. California, which established the "true threat" exception. This exception established a breach of free speech rights whenever the content of the speech maliciously invades privacy interests. However, this exception may only work in some doxing situations, where the court measures the extent of the offense and the reactions from the attack.
In the EU and UK, the GDPR privacy law gives personal data special protection, so that any data which can identify an individual must only be processed or used if one of the specified legal reasons allow it.
See also
Digital privacy
Infoveillance
Open-source intelligence
Revenge porn
Search engine privacy
Shadow profile
Sousveillance
Swatting
References
Epidemiology
Surveillance
Media studies
Privacy | Participatory surveillance | [
"Environmental_science"
] | 2,580 | [
"Epidemiology",
"Environmental social science"
] |
58,437,613 | https://en.wikipedia.org/wiki/Zeta%20diversity | In ecology, zeta diversity (ζ-diversity), first described in 2014, measures the degree of overlap in the type of taxa present between a set of observed communities. It was developed to provide a more generalized framework for describing various measures of diversity, and can also be used to test various hypotheses pertaining to biogeography.
Zeta diversity as an extension of other measures of diversity
α-diversity
The most basic measure of community diversity, alpha diversity (α-diversity), can be described as the average number of distinct taxonomic groups (e.g. unique genera or operational taxonomic unit) present, independent of their abundances, on a per sample basis. In the ζ-diversity framework this can be described as ζ1, the number of unique taxa present in one sample.
β-diversity
Beta diversity (β-diversity) is a measure to allow for a comparison between the diversity of local communities (α-diversity). The greater the similarity in community composition between multiple communities, the lower the value of β-diversity for that set of communities. Using the number of distinct taxonomic groups per community as a measure of α-diversity one can then describe β-diversity between two communities in terms of distinct number taxonomic groups held in common between them. Given two communities, A and B, a measure β-diversity between both communities can be described in terms of their overlap (ζ2) as well as the average number of unique taxonomic categories found in A and B (ζ1). In the framework of ζ-diversity we can then describe the average β-diversity, as described by the Jaccard index, for a set of samples as
Multi-site assemblages
The framework then for ζ-diversity can then be extended beyond measures of diversity in one (α-diversity), or between two communities (β-diversity), to describing diversity across sets of three or more communities. If ζ1 describes the number of distinct taxa in community A, and ζ2 describes the number of distinct taxa held in common between communities A and B, then ζn describes the number of distinct taxa held in common across n communities.
References
Measurement of biodiversity | Zeta diversity | [
"Biology"
] | 436 | [
"Biodiversity",
"Measurement of biodiversity"
] |
58,438,885 | https://en.wikipedia.org/wiki/Botryotrichum%20murorum | Botryotrichum murorum is a common soil and indoor fungus resembling members of the genus Chaetomium. The fungus has no known asexual state, and unlike many related fungi, is intolerant of high heat exhibiting limited growth when incubated at temperatures over 35 °C. In rare cases, the fungus is an opportunistic pathogen of marine animals and humans causing cutaneous and subcutaneous infection.
Taxonomy and discovery
Chaetomium murorum was first discovered by August Carl Joseph Corda in 1837 when he sampled the fungus from a wall in Prague. The Latin name "murorum" means "wall". In 2016 X. W. Wang et al. re-examined a set of cultures of Chaetomium-like fungi using phylogenetic analysis of the DNA directed RNA polymerase II subunit gene sequence. Chaetomium murorum, together with the genus Emilmuelleria, were then transferred to the genus Botryotrichum as the phylogenetic analysis confirmed that they clustered in the Botryotrichum clade. The current name for C. murorum is B. murorum.
Ecology
Botryotrichum murorum is a soil fungus also known to occur on animal dung of a range of animals including birds. It is also commonly found in indoor environment and on crops including sugarcane, rice, banana, pea, pumpkin, and cucumber. B. murorum is mesophilic with the optimum growing temperature of . It exhibits limited growth rate at 35 °C and above. This species grows on a wide range of microbiological growth media under standard clinical laboratory culture conditions, including oatmeal agar (OA), potato carrot agar (PCA), dichloran 18% glycerol agar (DG18), malt extract agar (MEA), and has shown to be able to metabolize keratin. Along with other close related species of Chaetomium such as C. globosum and C. funicola, B. murorum can degrade cellulose material in paper, as it expresses cellulase, xylanase, peroxidase, and laccase activities. The fungus can be utilized in waste degradation biotechnology.
Morphology
In MEA medium, the ascoma of the Chaetomiaceae-like species is categorized as perithecium with unique ornamentation attached to it. It appears to be brownish or purplish, lemon shaped, with jigsaw-puzzle like (textura epidermoidea) or interwoven (textura intricata) outer walls. The ascoma is typically 160-320 μm in height and 150-279 μm in diameter. The iconic long wavy terminal hair is four times longer than the ascoma, which can grow up to 3 mm long, ending with a curly tip. The ascoma also has shorter, wavy lateral hairs. The asci grow in bundles, usually club-shaped, and usually form eight irregularly arranged, 12–16.5 x 7–8.5 μm ball-shaped ascospores, with apical germ pores. The ascospores turn brown when mature. Although it is theoretically capable to reproduce asexually, only sexual morph is observed. The appearance and growth rate of B. murorum colonies vary depending on the growth medium. For example, MEA medium colonies appear to be unpigmented (white in colour) or light brown, and OA medium colonies appear to be purple at the center and unpigmented at the surrounding area. A certain degree of morphological diversity is observed in different cultures of the same species.
Pathogenesis
Even though the fungus is frequently found in indoor environment, and has been isolated from wide range of human food, only isolated subcutaneous infections due to superficial wound caused by contaminated material, such as contaminated agricultural tools, are reported. The infection can cause subcutaneous phaeohyphomycosis mostly in people with compromised immune systems. Symptoms include lesion, pus, thickening of skin, and chromoblastomycosis-like, muriform bodies-less tumorous mass, which makes it easily to be misdiagnosed. The fungus was reported to cause dark red, brownish plaques on chest and abdominal region in an agricultural worker. As B. murorum prefers to grow in body parts with lower temperature, most infections are located in extremities, skin, and nails. B. murorum can also cause cutaneous hyperplasia in marine animals.
Mycotoxins
Botryotrichum murorum produces the secondary metabolites Chaetoxanthone C and D, which cause selective cytotoxicity towards some human protozoan parasitic pathogens, such as Trypanosoma cruzi and Plasmodium falciparum. These metabolites are candidates for antiprotozoal drug. The chemical pigment isocochliodinol and neocochliodinol, unique to B. murorum and its close related fungus C. amygdalisporum, has shown cytotoxic activity towards HeLa cells.
References
Sordariales
Taxa named by August Carl Joseph Corda
Fungi described in 1837
Fungus species | Botryotrichum murorum | [
"Biology"
] | 1,104 | [
"Fungi",
"Fungus species"
] |
58,439,642 | https://en.wikipedia.org/wiki/Margham | Margham is an oil and gas field in Dubai, United Arab Emirates (UAE) and the largest onshore gas field in the emirate. The field is managed by Dusup - the Dubai Supply Authority. Condensate production ran at some 25,000 barrels per day in 2010. Margham also has an oil production capability.
Background
Production at Margham commenced in 1984, with three major gas-bearing formations located up to 10,000 feet below sea level. The field is connected by pipeline to Jebel Ali, where the gas condensate is loaded onto tankers for export. Dry gas is now also sent by pipeline to supply the Dubai grid, with consumption increasing since 2015.
Margham was initially developed as a liquids stripping/gas recycling project (dry gas was pumped back into the reservoir), but now operates as a gas storage facility for Dubai since 2008, allowing Dubai to depend on gas produced from Margham for its electricity generation and desalination needs. This usage, together with sustainables such as DEWA's Mohammed bin Rashid Al Maktoum Solar Park, means that Dubai has eliminated the use of oil as a domestic energy fuel.
Although it is a major producer with ambitions to develop its trading activities to become a major global LNG hub, the UAE is actually a net importer of LNG.
References
Natural gas fields in the United Arab Emirates
Energy | Margham | [
"Physics"
] | 286 | [
"Energy (physics)",
"Energy",
"Physical quantities"
] |
58,443,580 | https://en.wikipedia.org/wiki/DG%20Tauri%20B | DG Tauri B, near the T Tauri star DG Tauri, is a young stellar object located 450 light-years (140 parsecs) from Earth, within the Taurus constellation. Observations of DG Tauri B were first made in October, and later December 1995 at the 6 element Owens Valley millimeter wave array. Its most notable characteristics are its bipolar jets of molecular gas and dust emanating from either side of the object. Red-shifted carbon monoxide emissions extend out 6,000 AU to the northwest of the object from the undetermined source, and are symmetrically distributed about the jet, while blue-shifted CO emissions are confined to a region with a roughly 500 AU radius.
References
Taurus (constellation)
Astronomical objects discovered in 1995
Pre-main-sequence stars
Tauri, DG | DG Tauri B | [
"Astronomy"
] | 170 | [
"Taurus (constellation)",
"Constellations"
] |
58,444,213 | https://en.wikipedia.org/wiki/Stanford/ITS%20character%20set | Stanford/ITS character set is an extended ASCII character set based on SEASCII with modifications allowing compatibility with 1968 ASCII.
Usage
It is used as an alternate character set of the SUPDUP protocol for terminals with %TOSAI and %TOFCI bits set. It is also recommended for TeX implementations on systems with large character sets. The default plain TeX macro package sets values (↑) and (↓) as alternative character codes for superscripts and subscripts, respectively (the default being ^ and _).
The Knight keyboard is an example of a keyboard capable of inputting all of the defined characters excluding ⋅γδ±⊕◊∫, as they are mapped to ASCII commands NUL, HT, LF, FF, CR, ESC and DEL, respectively.
Coverage
Each character is encoded as a single seven-bit code value. It contains all 95 printable ASCII characters along with 27 mathematical symbols and 6 Greek letters.
Code page layout
See also
Stanford Extended ASCII
Incompatible Timesharing System
SUPDUP
TeX
References
Further reading
- (Historic) SUPDUP Protocol. October 1977.
Character encoding
Computer-related introductions in the 1970s | Stanford/ITS character set | [
"Technology"
] | 238 | [
"Natural language and computing",
"Character encoding"
] |
58,444,583 | https://en.wikipedia.org/wiki/7%CE%B1-Thiomethylspironolactone%20sulfoxide | 7α-Thiomethylspironolactone sulfoxide (also known as 7α-TMS sulfoxide, 7α-thiomethylspironolactone S-oxide, or 7α-methylsulfinylspironolactone) is a metabolite of spironolactone (brand name Aldactone), an antimineralocorticoid and antiandrogen medication. 7α-TMS sulfoxide is specifically formed from 7α-thiomethylspironolactone (7α-TMS).
References
Human drug metabolites
Lactones
Pregnanes
Spiro compounds
Spirolactones
Spironolactone
Sulfoxides | 7α-Thiomethylspironolactone sulfoxide | [
"Chemistry"
] | 160 | [
"Organic compounds",
"Chemicals in medicine",
"Human drug metabolites",
"Spiro compounds"
] |
58,445,345 | https://en.wikipedia.org/wiki/Lipid%20pump | The lipid pump sequesters carbon from the ocean's surface to deeper waters via lipids associated with overwintering vertically migratory zooplankton. Lipids are a class of hydrocarbon rich, nitrogen and phosphorus deficient compounds essential for cellular structures. This lipid carbon enters the deep ocean as carbon dioxide produced by respiration of lipid reserves and as organic matter from the mortality of zooplankton.
Compared to the more general biological pump, the lipid pump also results in a "lipid shunt", where other nutrients like nitrogen and phosphorus that are consumed in excess must be excreted back to the surface environment, and thus are not removed from the surface mixed layer of the ocean. This means that the carbon transported by the lipid pump does not limit the availability of essential nutrients in the ocean surface. Carbon sequestration via the lipid pump is therefore decoupled from nutrient removal, allowing carbon uptake by oceanic primary production to continue. In the Biological Pump, nutrient removal is always coupled to carbon sequestration; primary production is limited as carbon and nutrients are transported to depth together in the form of organic matter.
The contribution of the lipid pump to the sequestering of carbon in the deeper waters of the ocean can be substantial: the carbon transported below 1,000 metres (3,300 ft) by copepods of the genus Calanus in the Arctic Ocean almost equals that transported below the same depth annually by particulate organic carbon (POC) in this region. A significant fraction of this transported carbon would not return to the surface due to respiration and mortality. Research is ongoing to more precisely estimate the amount that remains at depth. The export rate of the lipid pump may vary from 1–9.3 g C m−2 y−1 across temperate and subpolar regions containing seasonally-migrating zooplankton. The role of zooplankton, and particularly copepods, in the food web is crucial to the survival of higher trophic level organisms whose primary source of nutrition is copepods. With warming oceans and increasing melting of ice caps due to climate change, the organisms associated with the lipid pump may be affected, thus influencing the survival of many commercially important fish and endangered marine mammals. As a new and previously unquantified component of oceanic carbon sequestration, further research on the lipid pump can improve the accuracy and overall understanding of carbon fluxes in global oceanic systems.
Lipid pump vs. biological pump
Through the seasonal vertical migration of zooplankton, the lipid pump creates a net difference between lipids transported to the deep during the fall (when zooplankton enter diapause) and what returns to the surface during the spring, resulting in the sequestration of lipid carbon at depth. The biological pump encompasses many processes that sequester the CO2 taken up in the surface ocean by phytoplankton through the export of POC to the deep ocean. Although zooplankton are known to play important roles in the biological pump through grazing and the repackaging of particulate matter, the active transport of seasonally-migrating zooplankton through the lipid pump has not been incorporated into global estimates of the biological pump.
Comparison between net fluxes
The biological pump transports 1–4 g C m−2 y−1 of POC below the thermocline annually. The export flux of POC in the temperate North Atlantic out of the surface waters was found to be 29 ± 10 g C m−2 y−1. However, studies have shown that processes such as consumption and remineralization contribute to a significant amount of this POC being attenuated as it sinks below the thermocline (near overwintering depths of ~1000 m). Furthermore, the remaining quantity of carbon in the North Atlantic from the export of POC below the thermocline has been calculated (2–8 g C m−2 y−1) to be comparable to the seasonal migration of C. finmarchicus in the North Atlantic (1–4 g C m−2 y−1) through the lipid pump. Therefore, the lipid pump may contribute 50–100% of C sequestration to the biological pump as net transport that has not been included in its current estimates.
Lipid shunt
Although the sequestration of marine carbon is a primary outcome of the biological pump, the recycling of nutrients such as N and P in organic matter plays a comparatively important role in maintaining the processes that facilitate this carbon export without removing nutrients for primary production. One key difference between the lipid pump and biological pump is that the ratios of nutrients such as nitrogen and phosphorus relative to carbon are minimal or zero in lipids, whereas the exported POC in the biological pump retains the standard Redfield ratios found throughout the world's oceans. This is primarily due to zooplankton in their copepodite stages releasing an excessive amount of nitrogen and phosphorus from excretion back into the surface. Thus, the production, transport, and metabolism of lipid carbon during overwintering do not contribute to a net consumption or removal of essential nutrients in the surface ocean, which is unlike many components of the biological pump. This process creates what is known as a "lipid shunt" in the biological pump, as the carbon sequestration of the lipid pump is decoupled from nutrient removal.
Overwintering diapause vs. Diel vertical migration
Diel Vertical Migration (DVM) is a well-studied phenomenon, widespread in the temperate and tropical oceans, and previously understood to be the most significant contributor to the active export of carbon as a result of zooplankton migration. The most common form is the nocturnal DVM, a night-time ascent to the upper pelagic and a daytime descent to deeper waters. A relatively unique variation of this form is the twilight DVM, where the ascent happens during dusk and the descent around midnight (i.e., midnight sinking).
While DVM occurs on a daily basis, overwintering diapause (hibernation) occurs on an annual time-scale and enables zooplankton species, particularly Calanus spp., to adapt to seasonal variation in primary productivity in specific ocean basins. Individuals enter diapause and migrate deeper in the water column to overwinter below the thermocline. During diapause they survive on stored lipid reserves that are generated at the end of their time at the surface when nutrients are widely available. The seasonal end of diapause must be closely timed with the beginning of the spring phytoplankton bloom to enable acquisition of food to permit proper egg development and hatching. If the timing is disrupted, eggs that are hatched during diapause will have limited growth time and a lower likelihood of surviving overwintering, as thus is an example of match-mismatch hypothesis. Calanus spp. in ocean basins with shorter growth seasons will be increasingly sensitive to the timing of the spring bloom, such as polar regions.
In the Arctic and Antarctic environments, the productive season is typically short and certain copepods species vertically migrate during overwintering diapause. During the productive seasons of spring and summer, younger developmental stages of these copepods usually thrive in food-rich, warmer, near-surface waters, and they rapidly develop and grow. During late summer and fall, grazing pressure, nutrient limitation, and annual variations of irradiance combine to limit the pelagic primary production. Consequently, the food supply fades toward fall, and overwintering diapause initiates. These copepods migrate to deeper waters with accumulated lipid reserves for overwintering. The overwintering diapause stages remain in deeper waters with limited physical and physiological activity and ascend back to the near-surface waters and complete the life cycle at the onset of the following productive season.
Calanus spp.
Ecology
Calanus spp. are abundantly distributed copepods, particularly in the polar and temperate North Atlantic. Studies attempting to quantify the lipid pump have primarily focused on the cousin species of C. finmarchicus, Calanus glacialis and Calanus helgolandicus, C. hyperboreus. C. hyperboreous, the largest of these species, uses an overwintering diapause (hibernation) strategy, and its life-history will be described in more detail as a representative Calanus spp. With a life cycle of two to six years on average, each C. hyperboreous individual can go through multiple overwintering periods. Positively buoyant eggs are spawned by females at depth and rise to the surface. Larvae (nauplii) first develop from these eggs, and complete their maturation into an early juvenile (copepodite) within one season, after which they undergo their first overwintering. Copepodite have three stages before maturing to the adult stages. While female Calanus spp. are generally expected to experience mortality after spawning, some may return to the surface to build up lipid stores before entering another overwintering and reproductive cycle.
Lipid accumulation and metabolism
Lipids are stored by all copepodite and adult Calanus spp. in an oil sac, which can account for up to 60% of an individual's dry weight. Calanus spp. accumulate these lipids while feeding closer to the ocean surface during the spring and summer months, aligning with phytoplankton blooms. Early in the growing season, Calanus spp. biogenergetics are allocated to reproduction, feeding and growth, but eventually shift to the production of lipids to provide energy during diapause. These lipids take the form of wax esters, energy-rich compounds like omega-3 fatty acids, and long-chain carbon molecules. At the end of the feeding/growing season, Calanus spp. migrate downward, with to depths varying from 600 to 3000m, but with the requirement that Calanus spp. settle below the thermocline to prevent premature return to the surface waters. Stored lipids are metabolized at these depths, accounting for approximately 25% of the basal metabolic rate. A 6–8 month-long overwintering period can drain a substantial fraction (44–93%) of the stored lipids despite the decreased metabolism.
Physical characteristics
The physical characteristics of Calanus spp. (i.e., dry weight, prosome length, lipid content, and carbon content) are always changing, varying between different regions, temporally, and across life stages. Based on isomorphism, or the similarity in form or structure of organisms, Calanus spp. may deviate in size but their basic physical structure remains constant across different overwintering stages and between different copepod species. The only significant taxonomic difference is the number of segments on the tail across developmental stage CIII and older (CIV, CV). With an outcome of isomorphism, dry weight (d [mg]) and prosome length (p [mm]) can be scaled as they are related as d = cp3, where c is a coefficient. Observations identify the relationship between dry weight and prosome length with a coefficient between 3.3 and 3.5 for C. hyperboreus. Although this relationship is not supported extensively by empirical evidence, it has been used for model frameworks to observe Calanus spp. carbon content.
Relationships between NAO and Calanus spp. populations
In the North Atlantic and Nordic Seas, a primary long-term forcing that affects Calanus spp. and its habitat is the North Atlantic Oscillation (NAO) index, defined as the normalized difference in sea surface pressure between the Azores High and the Icelandic Low. While high NAO index values indicate a net flow of Atlantic water to the northeast and into the Norwegian Sea, low NAO index values indicate a reduced Atlantic water inflow into the Nordic Seas. In the Northwestern Atlantic, positive trends in the abundances of Calanus spp. correspond with higher sea surface temperatures and positive NAO forcing with a lag of one or two years. However, the influence of the NAO in explaining Calanus spp. abundance was substantially diminished when temporal autocorrelation and detrending analyses were involved.
Regional differences
Certain aspects of the lipid pump such as the diapause depth and duration of zooplankton can vary among regions that have different overwintering temperatures and resident community characteristics. There are other subarctic regions that have shown similar carbon export rates to those found in the temperate North Atlantic (1–4 g C m−2 y−1) via seasonally-migrating zooplankton. For instance, C. glacialis and C. hyperboreus are the most dominant zooplankton species found in the Arctic Ocean at similar latitudes, and they contribute to a 3.1 g C m−2 y−1 flux of lipid carbon below 100 m during overwintering. A slightly higher maximum flux in lipid carbon (2–4.3 g C m−2 y−1) below 150 m was observed in the subarctic North Pacific and was primarily attributed to the Neocalanus genus of copepods. In these areas, N. flemingeri, N. cristatus, and N. plumchrus are the primary contributors to the lipid pump, whereas, the subantarctic Southern Ocean consists primarily of N. tonsus contributing to a lipid carbon flux of 1.7–9.3 g C m−2 y−1 out of the euphotic zone. The rates or magnitude of these processes may slightly vary due to characteristic differences between these subpolar regions, which have largely been under-studied relative to their contributions to the lipid pump.
Ecological impacts
Role in the food web
The zooplanktonic Calanus spp. are not only important for moving carbon out of the photic zone and into the deep ocean, but these lipid-rich organisms play a critical role in the success of many marine species that depend on them as food. They comprise the majority of diets for fishes, seabirds and even large mammals such as whales. Copepods can account for about 70–90% of total zooplankton biomass, depending on region. Additionally, their eggs are a main source of food for commercially important fish stocks. The copepod eggs are buoyant and will rise to the sea surface, but are susceptible to predation by fish and other organisms. Copepods also provide the benthic community with food via sinking fecal pellets, meaning that as fish and smaller invertebrates excrete waste, that waste falls to the sea floor and organisms on the sea floor compete for the pellets as food. The role of copepods in the food web is crucially intertwined amongst other organisms.
Copepod abundance, specifically the C. finmarchicus, has a direct impact on the endangered right whales of the North Atlantic. North Atlantic right whales rely on copepods as their primary prey in order to meet their nutritional needs. To meet the right whale's energetic requirements they need about 500 kg of C. finmarchicus a day. Each copepod measures about 2–4 millimetres long which is about the size of a grain of rice and they weigh, on average, between 1.0274 and 1.0452 g cm−3. A loss in C. finmarchicus has the potential to affect the right whale's migration, reproduction, and/or ability to successfully nurse their young (only for lactating females).
Economic impacts
Many commercial and subsistence fisheries in arctic and subarctic regions fish for cod, salmon, crab, groundfish, and pollock depend on this energy-rich zooplankton as food. In 2017, the highest value of commercial fish species for the US was salmon ($688 million), crabs ($610 million), shrimp ($531 million), scallops ($512 million), and pollock ($413 million). Pollock alone is the largest fishery in the US based on volume, but is also the second largest fishery in the world supporting 2–5% of the global fishery production. Not only do millions of people rely on fish for subsistence, but recreational fishing is one of the most popular activities in the US. Recreational fishing contributes about $202 million to the US economy. Changes in the abundance and distribution of copepods could drastically affect the economic livelihoods of millions of people connected to the fishing industry or who rely on fishing as a primary source of protein.
Climate change impacts
Anthropogenic climate change is estimated to impact the marine environment in a variety of ways. In the arctic and subarctic environments where a vast majority of Calanus spp. reside, melting ice caps and timing of the spring phytoplankton bloom could have implications for copepod density, distribution and timing of return from overwintering. A phytoplankton bloom occurs in the spring in arctic and subarctic environments when sea ice melts, allowing an increase in light to penetrate deeper into the water column, thus supporting photosynthesis. An input of freshwater from the sea ice melting increases the stratification of the ocean in the summertime. Stratification leaves nutrient-rich water on the bottom and nutrient-poor water on the top due to an increase in freshwater from the ice. However, in the wintertime, this region of the world experiences an increase in storms that bring nutrient-rich waters into the more nutrient-poor surface waters. Climate change alters the timing of the spring bloom by promoting an earlier or later ice melt. Warmer waters could lead to weaker stratification, meaning the density differences between the first and second layer of the ocean are increasing due to an increased flux of freshwater from ice melt. Typically, the amount of total annual primary productivity in the Bering Sea associated with a spring bloom is approximately 10–65%, however warmer waters could impact the amount of primary production occurring.
Reproduction and changes to the food web
For the C. finmarchicus species specifically, the start of reproduction is linked to the start of the spring bloom. Thus, changes in the timing of the spring bloom would directly influence the reproductive capabilities of C. finmarchicus and alter the food chain from the bottom-up. However, the food chain could also be altered from the top-down through habitat disturbance and the removal of marine mammals and fish. Large-scale commercial fisheries exert top-down effects by lowering the abundance of larger species and increasing the amount of lipid-rich copepods and even paving way for other species to consume them. Under warming ocean conditions, prey switching is to be expected. Egg production and hatching success may also be affected with increasing sea surface temperatures and ocean acidification.
Physical ocean
Other climate change factors to consider that might influence these lipid-rich copepods are shifts of current systems, storm activity and sea-ice cover. In some regions of the arctic, specifically the Bering Sea, studies have forecasted a decrease in storms due to warming. This impacts the mixing of the water column that brings nutrient-rich water upwards. Copepods consume primary producers that require nutrients to survive. Limiting the amount of nutrients in the water column could decrease the abundance of these primary producers and subsequently reduce Calanus spp. abundance as well.
Changes in the water masses and temperature could have a direct effect on the zooplankton's vertical migration. The distribution of the zooplankton in the water column is controlled by the currents. The Calanus spp. use the water column for their vertical migration. Changes to the currents while Calanus spp. are in diapause could result in a reduction in the abundance of the copepods in the Norwegian Sea. Since the lipid pump is controlled through the movement of copepods, particularly Calanus spp., impacts of climate change that affect copepod abundance or seasonal migration will directly impact the lipid pump and carbon export to the deep ocean.
Climate modeling
A study that utilized climate modeling to simulate the effects of predicted increases in water temperature and salinity as a result of climate change on C. finmarchicus of the eastern shelf of North America forecasts lower abundance of copepods. The decrease in favorable environmental conditions is expected to decrease the size and density of C. finmarchius, and will likely have negative effects on whales and other components of the food web that are inextricably tied to copepods. The impact of diapause and variation in seasonal productivity was not explicitly included as increasing model complexity and more accurate accounting for Calanus spp. metabolic processes during diapause is required. The importance of diapause timing with spring plankton blooms is well-established, suggesting that there is potential for additional population impacts as a result of climate change, which would further reverberate throughout the ecosystem.
Key implications
The 2015 paper by Jónasdóttir et al., marked the first comprehensive accounting for the amount of carbon sequestration resulting from the movement of lipids by vertically migrating zooplankton during their overwintering diapuse. Although only elucidating the impact of one particular species, in this case, C. finmarchicus, both the magnitude of carbon flux and widespread global distribution of Calanus spp. suggest the possible importance of the lipid pump in global carbon cycling by contributing an estimated 50–100% of carbon sequestration to the biological pump. Subsequent research has underscored this significance as estimates that attempt to more accurately account for the mortality and respiration rates of other overwintering Calanus spp. have suggested similar, although regionally variable, magnitudes of carbon export from the lipid pump. Overwintering diapause is an ecological strategy to enable Calanus spp. to adapt to the seasonal variability in food availability in ocean basins. Changes in the timing or length of high food periods are likely to negatively impact the distribution and abundance of Calanus spp. Changes in ocean temperature and salinity due to anthropogenic climate change are also predicted to decrease concentrations of Calanus spp. in some ocean basins. In addition to potential ecosystem impacts due to the large number of species that rely on copepods as a major constituent of their diets, there may be implications for oceanic carbon sequestration from consequent changes in the magnitude of the lipid pump due to overwintering zooplankton.
Future directions
The global estimates of the biological pump have yet to include the elements of the lipid pump which could represent 50–100% of C export that is not accounted for. This is likely due to many observational challenges pertaining to the analysis of these seasonal migrations. As described above, more accurate ways to measure both mortality and respiration rates of overwintering zooplankton are being conducted in recent work, which are the two factors that primarily control the amount of lipid carbon that is sequestered at depth. For the zooplankton that survive overwintering, their upward migration during the spring returns a fraction of the lipid reserves to the surface as nonrespired carbon, with losses attributed to predation by deep-dwelling predators, disease, starvation, and other sources of mortality generally not accounted for. Similar to the lysis shunt, the dynamics of the lipid shunt causes uncertainty in observational methods of the lipid pump when comparing its efficiency to that of the biological pump. Additionally, large zooplankton usually avoid mooring instruments such as sediment traps during seasonal migrations which further explains why the lipid pump has yet to become incorporated into estimates of the global carbon export flux. These observations can be challenging to make given the remote locations they are conducted in and the harsh, deep sampling conditions, but these adaptations in the data collection are needed to better integrate global estimates of the carbon export flux provided by the lipid pump.
See also
Biological pump
Oceanic carbon cycle
References
Chemical oceanography
Carbon dioxide removal | Lipid pump | [
"Chemistry"
] | 4,929 | [
"Chemical oceanography"
] |
58,446,188 | https://en.wikipedia.org/wiki/Electric%20motor%20brake | An electric motor brake (commonly referred to as an electric brake) is a safety feature incorporated into many modern power tools, such as circular saws, drills, and miter saws. Many manufacturers implement this feature into tools specifically with a spinning blade or cutter.
Usage in corded tools
An electric brake is commonly used in corded tools such as circular saws, miter saws, routers, bandsaws, angle grinders, and more recently, table saws. These mechanisms are designed to prevent injuries resulting from things like kickback or skin-to-blade contact. The way these mechanisms work are almost universally the same; when the trigger or switch is released, the polarity of the electricity running to the motor's brushes is reversed, which decelerates the motor to a stop much quicker than it otherwise would. In circular saws, this feature can reduce the risk of the saw jolting backwards when the saw is set down, as well as prevent damage to the cord or the user. In other tools (such as miter saws or table saws), the brake can reduce the risk of injury to an operator's fingers or hands when the saw is switched off (such as when grabbing a scrap piece off the table). The disadvantage of this feature is that it wears the brushes prematurely when compared to non-brake tools. The first use of an electric brake on a tool was that of the miter saw, invented in 1964 by Ed Niehaus, a tool engineer for Rockwell Tools. Since then, a number of manufacturers have incorporated brakes into their power tools.
Usage in cordless tools
Electric brakes on cordless tools have been prevalent since the invention of the first cordless drill by Makita in 1969. They are found on most cordless tools, with the exception of cordless vacuums and blowers, etc., where such a feature offers no benefit. The way the brake on cordless tools works is slightly different than in corded models; when the switch is released, the motor terminals are shorted together, causing the motor to stop almost instantly by dissipating the rotational energy in the windings. This method is practical for the small permanent-magnet motors in cordless tools, which have low inertia, and is applicable to both brushed and brushless variants. This would not work on corded tools, as they generally use wound field magnets instead of permanent magnets.
References
Power tools
Brakes | Electric motor brake | [
"Physics"
] | 503 | [
"Power (physics)",
"Power tools",
"Physical quantities"
] |
58,446,217 | https://en.wikipedia.org/wiki/Calcium%20cycle | The calcium cycle is a transfer of calcium between dissolved and solid phases. There is a continuous supply of calcium ions into waterways from rocks, organisms, and soils. Calcium ions are consumed and removed from aqueous environments as they react to form insoluble structures such as calcium carbonate and calcium silicate, which can deposit to form sediments or the exoskeletons of organisms. Calcium ions can also be utilized biologically, as calcium is essential to biological functions such as the production of bones and teeth or cellular function. The calcium cycle is a common thread between terrestrial, marine, geological, and biological processes. Calcium moves through these different media as it cycles throughout the Earth. The marine calcium cycle is affected by changing atmospheric carbon dioxide due to ocean acidification.
Calcium weathering and inputs to seawater
Calcium is stored in geologic reservoirs, most commonly in the form of calcium carbonate or as calcium silicate. Calcium-containing rocks include calcite, dolomite, phosphate, and gypsum. Rocks slowly dissolve by physical and chemical processes, carrying calcium ions into rivers and oceans. Calcium ions (Ca2+) and magnesium ions (Mg2+) have the same charge (+2) and similar sizes, so they react similarly and are able to substitute for each other in some minerals, such as carbonates. Ca2+-containing minerals are often more easily weathered than Mg2+ minerals, so Ca2+ is often more enriched in waterways than Mg2+. Rivers containing more dissolved Ca2+ are generally considered more alkaline.
Calcium is one of the most common elements found in seawater. Inputs of dissolved calcium (Ca2+) to the ocean include the weathering of calcium sulfate, calcium silicate, and calcium carbonate, basalt-seawater reaction, and dolomitization.
Biogenic calcium carbonate and the biological pump
Biogenic calcium carbonate is formed when marine organisms, such as coccolithophores, corals, pteropods, and other mollusks transform calcium ions and bicarbonate into shells and exoskeletons of calcite or aragonite, both forms of calcium carbonate. This is the dominant sink for dissolved calcium in the ocean. Dead organisms sink to the bottom of the ocean, depositing layers of shell which over time cement to form limestone. This is the origin of both marine and terrestrial limestone.
Calcium precipitates into calcium carbonate according to the following equation:
Ca2+ + 2HCO3− → CO2+ H2O + CaCO3
The relationship between dissolved calcium and calcium carbonate is affected greatly by the levels of carbon dioxide (CO2) in the atmosphere.
Increased carbon dioxide leads to more bicarbonate in the ocean according to the following equation:
CO2 + CO32− + H2O → 2HCO3−
With ocean acidification, inputs of carbon dioxide promote the dissolution of calcium carbonate and harm marine organisms dependent on their protective calcite or aragonite shells. The solubility of calcium carbonate increases with pressure and carbon dioxide and decreases with temperature. Thus, calcium carbonate is more soluble in deep waters than surface waters due to higher pressure and lower temperature. As a result, precipitation of calcium carbonate is more common in shallower oceans. The depth at which the rate of calcite dissolution equals the rate of calcite precipitation is known as calcite compensation depth.
Changes in global climate and the calcium cycle
Ocean acidity due to carbon dioxide has already increased by 25% since the industrial revolution. As carbon dioxide emissions continually increase and accumulate, this will negatively affect the lives of many marine ecosystems. The calcium carbonate used to form many marine organisms' exoskeletons will begin to break down, leaving these animals vulnerable and unable to live in their habitats. This ultimately has a flow on effect to predators, further affecting the function of many food webs globally.
Changes in calcium concentrations over geologic time
Calcium stable isotopes have been used to study inputs and outputs of dissolved calcium in marine environments. For example, one study found that calcium levels have decreased between 25 and 50 percent over a 40 million year timespan, suggesting that dissolved Ca2+outputs have exceeded its inputs. The isotope Calcium-44 can help to indicate variations in calcium carbonate over long timespans and help explain variants in global temperature. Declines in the isotope Calcium-44 usually correlate with periods of cooling, as dissolution of calcium carbonate typically signifies a decrease in temperature. Thus, Calcium isotopes correlate with Earth's climate over long periods of time.
Human/animal use of calcium
Being an essential element, calcium is obtained through dietary sources, the majority of which comes from dairy products. The most significant mechanisms controlling calcium use within the body are intestinal absorption, renal filtration, renal reabsorption and bone turnover, which are controlled predominantly by hormones and their corresponding receptors in the gut, kidneys and bones respectively. This allows for calcium use throughout the body, namely in bone growth, cellular signalling, blood clotting, muscle contraction and neuron function.
Calcium is one of the essential components of bone, contributing to its strength and structure in addition to being the main site at which it is stored within the body. Within the muscles, its primary use is to enable contractions. Muscle cells draw calcium from the blood, allowing it to bind with troponin, a component of the muscle fibre that signals for a contraction by moving actin and myosin. After a contraction, calcium dissipates and the filaments move back to a resting state before the release of more calcium for the next contraction. Furthermore, calcium plays a significant role in allowing nerve impulses to be transmitted between neurons. The release of calcium ions from voltage gated ion channels signals for the release of neurotransmitters into the synapse. This allows for the depolarisation of a neuron, thus transmitting the signal to the next neuron where this process is once again repeated. Without the presence of calcium ions, the release of neurotransmitters would not occur, preventing signals from being sent and hindering body processes.
Negative feedback mechanisms are implemented in order to control calcium levels. When low calcium levels are detected in the body, the parathyroid releases parathyroid hormone (PTH) which travels through the bloodstream to the bones and kidneys. In the bones, the presence of PTH stimulates osteoclasts. These cells break down bone to release calcium into the bloodstream where it can be used by the rest of the body in the above processes. In the kidneys, PTH stimulates re-absorption of calcium so it in not lost from the body through urine and returned to the bloodstream instead. Lastly, PTH acts on the intestines by indirectly promoting enzymes that activate vitamin D, a signal for the intestines to absorb more calcium, further increasing blood calcium levels. This will continue until the body releases too much calcium into the bloodstream. Excess calcium then promotes the release of calcitonin from the thyroid gland, effectively reversing the process of PTH. Osteoclast activity is stopped and osteoblasts take over, utilising the excess calcium in the bloodstream to form new bone. Calcium re-absorption in the kidney is prevented, allowing the excretion of excess calcium through the urine. Through these hormonal mechanisms, calcium homeostasis is maintained within the body.
Calcium in plants and soil
Calcium is an essential component of soil. When deposited in the form of lime, it cannot be used by plants. To combat this, carbon dioxide produced by plants reacts with water in the environment to produce carbonic acid. Carbonic acid is then able to dissolve limestone, enabling the release of calcium ions. This reaction is more readily available with smaller particles of limestone than it is with large pieces of rock due to the increased surface area. When lime is leached into soil, calcium levels inevitably increase, both stabilising pH and enabling calcium to mix with water to form Ca2+ ions, thus making it soluble and accessible to plants to be absorbed and utilised by the root system. The calcium ions travel up the xylem of the plant alongside water to reach the leaves. The plant can utilise this calcium in the form of calcium pectate to stabilise cell walls and provide rigidity. Calcium is also used by plant enzymes to signal growth and coordinate life-promoting processes. Additionally, the release of calcium ions enables microorganisms to access phosphorus and other micro nutrients with greater ease, improving the soil ecosystem drastically thus indirectly promoting plant growth and nutrition.
Inevitable plant and animal death results in the return of calcium contained within the organism back into the soil to be utilised by other plants. Decomposing organisms break them down, returning the calcium back into the soil and enabling the cycling of calcium to continue. Additionally, these animals and plants are eaten by other animals, similarly continuing the cycle. It is however important to note the modern introduction of calcium into the soil by humans (through fertilisers and other horticultural products) has resulted in a higher concentration of calcium contained within soil.
Industrial uses of calcium and its impact on the calcium cycle
The naturally occurring calcium cycle has been altered by human intervention. Calcium is predominantly extracted from limestone deposits to be utilised by many industrial processes. Purification of iron ore and aluminium, replacing asbestos brake linings and some coatings for electric cables, are some of these major uses of calcium. Furthermore, calcium is used within the household to maintain alkaline pH of swimming pools, counteracting acidic disinfectants and in the food production industry to produce bicarbonate soda, some wines and dough.
With its widespread uses, a large volume of calcium must be obtained from mines and quarries to supply the high demand. As more limestone and water is removed from mines, underground stores of rock are often weakened making the ground more susceptible to sink holes. Sinkholes and mining both affect the presence of groundwater, potentially leading to a lower water table or altered pathways of flowing water. This may affect local ecosystems or farmland as the water supply is restricted. Additionally, the water that is released from mining areas will have higher concentrations of dissolved calcium. This can either be released into oceans or absorbed by the soil. Whilst not always detrimental, it alters the natural calcium cycle which may have flow-on effects for ecosystems. Furthermore, water being pumped from mines increases the danger of downstream flooding whilst simultaneously decreasing the volume on water in upstream reservoirs such as marshes, ponds of wetlands It is however important to note than limestone mining is comparatively less damaging than other mining process, with potential to restore the environment after the mine is no longer in use
The importance of the calcium cycle and future predictions
The calcium cycle links ionic and non ionic calcium together in both marine and terrestrial environments and is essential for the functioning of all living organisms. In animals, calcium enables neurons to transmit signals by opening voltage gated channels that allow neurotransmitters to reach the next cell, bone formation and development and kidney function, whilst being maintained by hormones that ensure calcium homeostasis is reached. In plants, calcium promotes enzyme activity and ensures cell wall function, providing stability to plants. It also enables crustaceans to form shells and corals to exist, as calcium provides structure, rigidity and strength to structures when complexed (combined) to other atoms. Without its presence in the environment, many life-preserving processes would not exist. In the modern context, calcium also enables many industrial processes to occur, promoting further technological developments.
With its close relation to the carbon cycle and the effects of greenhouse gasses, both calcium and carbon cycles are predicted to change in the coming years. Tracking calcium isotopes enables the prediction of environmental changes, with many sources suggesting increasing temperatures in both the atmosphere and marine environment. As a result, this will drastically alter the breakdown of rock, the pH of oceans and waterways and thus calcium sedimentation, hosting an array of implications on the calcium cycle.
Due to the complex interactions of calcium with many facets of life, the effects of altered environmental conditions are unlikely to be known until they occur. Predictions can however be tentatively made, based upon evidence-based research. Increasing carbon dioxide levels and decreasing ocean pH will alter calcium solubility, preventing corals and shelled organisms from developing their calcium-based exoskeletons, thus making them vulnerable or unable to survive.
References
Biogeochemical cycle
Biochemistry | Calcium cycle | [
"Chemistry",
"Biology"
] | 2,546 | [
"Biogeochemical cycle",
"Biogeochemistry",
"Biochemistry",
"nan"
] |
58,446,396 | https://en.wikipedia.org/wiki/Keratinophyton%20durum | Keratinophyton durum is a keratinophilic fungus, that grows on keratin found in decomposing or shed animal hair and bird feathers. Various studies conducted in Canada, Japan, India, Spain, Poland, Ivory Coast and Iraq have isolated this fungus from decomposing animal hair and bird feathers using SDA and hair-bait technique. Presence of fungus in soil sediments and their ability to decompose hairs make them a potential human pathogen.
History and taxonomy
Keratinophyton durum was first described by Hugo Zukal in 1890 as Gymnoascus durus, and subsequently has been the subject of taxonomic confusion. Nearly 100 years after Zukal's description, Currah transferred the fungus from genus Gymnoascus to Keratinophyton (1985) and eventually to genus Aphanoascus (1986) due to similarity in their ascospores. At the same time, Guého and Vroey treated the fungus under the name, Anixiopsis biplanata (1986). The genera Aphanoascus and Anixiopsis have ascospores of similar appearance. This led to a debate within the mycological community upon its naming, wherein some mycologists used Anixiopsis biplanata and others used Aphanoascus durus to describe this species. Amidst this debate, the fungus was misclassified under the genus Ascocalvatia by von Arx in 1986. Ascocalvatia has cylindrical ascospores whereas Aphanoascus spores are flat and circular (oblate) in shape. Finally, in 1990 it was re-classified as Aphanoascus durus by Cano and Guarro. The name Keratinophyton durum was originally applied to the sexual state of the fungus (teleomorph), but now is used to include all life stages. The correct name for this species is K. durum.
Genomic information
Listed below are identified gene sequences for this fungus.
Morphology and growth
Ascospores found within the ascoma, are oblate (shaped like an M&M candy) and yellow-yellowish brown in color when observed in transmitted light microscopy. Typically, the lateral sides of these ascospores are smooth with a bumpy, pitted equatorial edge. Ascospores of this fungus are similar in appearance (morphology) to those of A. terreus by Apnis (Cano & Guarro, Randhawa & Sandhu) A. clathratus and A. hispanicus by Cano & Guarro. Ascospores of A. terreus and A. hispanicus are small, pitted and diamond-shaped (rhomboid), whereas A. clathratus has circular (oblate) ascospores with reduced pitting. Ascomata are spherical (globose) to oval (subglobose), pale yellowish brown to dark reddish brown in color, and range from 280 to 800 μm in diameter. Ascomata are encased in white aerial hyphae and conidia.
In laboratory, this fungus can be grown on 2% malt agar, potato-carrot agar (PCA), phytone yeast extract agar (PYE) and yeast-starch agar (YpSs) growth mediums. On 2% malt agar, post 2-week incubation, K.durum colonies reach up to 35–40 mm in diameter. Colonies appear fluffy and white but have uneven growth. Mostly thinly spread colonies are denser at the centre and can reach 2 mm in height. Hyphae are usually branched, hyaline, smooth-walled and septate. Colonies also contain aleurioconidia. On potato-carrot agar (PCA), rapid growth is observed at 25 °C. Within 14 days of PCA culturing, circular colonies measuring 53–67 mm in diameter can be seen. Initial colonies appear white, but later on change their color and appear greenish grey. In this growth media, resulting ascomata are scattered and there is limited production of conidia. On phytone yeast extract agar (PYE), fungus grows rapidly into white-yellowish white colonies. While conidiogenesis is prominent, ascomata are not produced. On YpSs growth medium, under dark conditions and 28 °C, it grows at the rate of 2–3 mm per day. Cream-coloured colonies with smooth, septate, hyaline hyphae can be observed. Hyphae are thin-walled and wide, measuring 1.7–2.5 μm in width. Ascoma maturation can be observed in 20–23 days. Acomata are encased in round, dark-brown aerial mycelium measuring 500–1050 μm in diameter.
Additionally, the fungus can be isolated using hair-baiting technique and followed by incubation on Sabouraud's dextrose agar (SDA). Isolation using Sabouraud's dextrose agar supplemented with (50 mg/L) chloramphenicol and cycloheximide (500 mg/L), requires 5–10 day, room temperature incubation. Similarly, hair baiting technique involving sterile human or horse hair can also be used to isolate this fungus from wet soils (rivers and lakes). Pocket-like surface erosion in human hair caused by this fungus can be observed under a light microscope following staining with lactophenol cotton blue.
Habitat and ecology
Typically, it has been isolated from depth of 3–5 cm in soils containing decomposing feather and animal hair. K. durum is known from soils of Gir Forest National Park (India), Sanjay Gandhi National Park, Kaziranga national park, Lonar crater lake as well as Shatt Al-Arab river (Iraq). In terrestrial ecosystems, this fungus is predominantly found areas where there is increased animal and bird densities. In underwater sediments, it prefers alkaline pH conditions. A study conducted in Shatt Al-Arab river by Abdullah and Hassan, demonstrated that the soil pH range for this fungi is 6.9. It is also found in Lonar lake sediments where water is highly alkaline (pH of 10.5–11.2) with increased concentrations of sodium chloride, fluorides and bicarbonates.
Pathogenicity
In their study, Deskhmukh & Verekar determined that it releases keratin at the rate of 234.6 μg/mL and is capable of decomposing 26.4% of human hair within four weeks of incubation. Since this fungus occurs in close proximity of animals and birds, it may be pathogenic to animal and humans.
References
Onygenales
Taxa named by Hugo Zukal
Fungus species | Keratinophyton durum | [
"Biology"
] | 1,432 | [
"Fungi",
"Fungus species"
] |
58,446,996 | https://en.wikipedia.org/wiki/Aspergillus%20novofumigatus | Aspergillus novofumigatus is a species of fungus in the genus Aspergillus. It is from the Fumigati section. Several fungi from this section produce heat-resistant ascospores, and the isolates from this section are frequently obtained from locations where natural fires have previously occurred. The species was first described in 2006. It was isolated from soil from the Galapagos Islands. It has been shown to produce aszonalenin, cycloechinuline, fiscalins, helvolic acid, neosartorin, palitantin, terrein, and territrem B.
In 2014, the genome of A. novofumigatus was sequenced as a part of the Aspergillus whole-genome sequencing project - a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 32.44 Mbp.
References
novofumigatus
Fungi described in 2006
Fungus species | Aspergillus novofumigatus | [
"Biology"
] | 206 | [
"Fungi",
"Fungus species"
] |
58,447,113 | https://en.wikipedia.org/wiki/Aspergillus%20brevijanus | Aspergillus brevijanus is a species of fungus in the genus Aspergillus. It is from the Jani section. The section only contains the two species A. brevijanus and A. janus. The colonies of the members of the section have both white and green sections. The species was first described in 2008.
In 2016, the genome of A. brevijanus was sequenced as a part of the Aspergillus whole-genome sequencing project - a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 36.00 Mbp.
Growth and morphology
A. brevijanus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
brevijanus
Fungi described in 2008
Fungus species | Aspergillus brevijanus | [
"Biology"
] | 201 | [
"Fungi",
"Fungus species"
] |
58,447,283 | https://en.wikipedia.org/wiki/Aureoumbra%20lagunensis | Aureoumbra lagunensis is a unicellular planktonic marine microalga that belongs in the genus Aureoumbra under the class Pelagophyceae. It is similar in morphology and pigments to Aureococcus anophagefferens and Pelagococcus subviridis. The cell shape is spherical to subspherical and is 2.5 to 5.0 μm in diameter. It is golden-coloured and is encapsulated with extracellular polysaccharide layers and has a single chloroplast structure with pigments.
Aureoumbra lagunensis thrives in a warm hypersaline environment as the greatest cell density has been found in water with salinity higher than 40 PSU and with temperatures between . Generally, the density of A. lagunensis is in the order of 106 cells mL−1, being higher in the summer months with lower abundance during the winter.
Aureoumbra lagunensis causes harmful algal blooms and was the dominant microalga in the 7 year long brown tide (1990 - 1997) that happened in Laguna Madre, Texas. Its dominance over other coexisting phytoplankton is in part associated with its encapsulating mucus layer of exopolymer secretions (EPS) and its ability to revert from vegetative and resting cell forms. The A. lagunensis blooms cause a substantial increase in light attenuation, which in turn contributes to marine biodiversity loss, particularly phytoplankton communities and benthic invertebrates. A. lagunensis thrives in low-light conditions, where it can maintain high growth rates at 150 umol photons m−2 s−1, thus an increase in light attenuation causes a positive feedback which further perpetuates blooms.
Aureoumbra lagunensis nutrient uptake is unlike other common microalgae. It uptakes inorganic nitrogen in the form of ammonium (NH4+) and nitrite (NO2−) and organic nitrogen in the form of urea, but does not utilize nitrate (NO3−). It uses environment dissolved organic phosphorus as the sole source to regenerate phosphate for growth.
Nomenclature
The name Aureoumbra lagunensis is Latin derived, where "Aureo" comes from the word Aureus meaning golden, pertaining to the colour of A. lagunensis populations; umbra refers to the reduction in light penetration that occurs when blooms occur, and lagunensis refers to the lagoon environment, namely Laguna Madre, Texas, from which this organism was first isolated.
Pigment characterization
Chlorophyll a
Chlorophyll c
Fucoxanthin
Diatoxanthin
Diadinoxanthin
19'-butanoyloxyfucoxanthin
β,β-Carotene
Distribution
Aureoumbra lagunensis causes harmful algal blooms, most notably in Laguna Madre, Texas from 1990 to 1997, where it was first isolated. For over 20 years, A. lagunensis was confined to this bay system in Texas. More recently, small background concentrations of the species have been found in coastal bay regions along the rest of the Mexican Gulf coast, with larger populations found in Florida, Texas, and Mexico. In 2012 and 2013, A. lagunensis also caused brown tides in the Indian River Lagoon and Mosquito Lagoon, in Florida, USA. A. lagunensis brown tides have expanded as far as the Caribbean Sea into Guantánamo Bay, Cuba in 2013.
The Texas brown tide
Aureoumbra lagunensis cause a bloom in Laguna Madre, Texas for seven years where it maintained densities from 0.5 x 106 cells mL−1 to 5 x 106 cells mL−1. The hypersaline conditions of Laguna Madre (45 – 75 PSU) is thought to be the cause of the bloom which allowed A. lagunensis to thrive, as they achieve maximal growth at 70 PSU and can continue to grow in environments of 10 – 90 PSU. The development of these hypersaline conditions was due to a period of drought which caused a loss of benthic and planktonic grazers. This effectively reduced the grazing pressure on phytoplankton like A. lagunensis. In December 1990 a large fish die-off occurred upon severe freezing which served to release nutrients like ammonium to further support the phytoplankton population. By October 1997, The Texas Brown Tide was disrupted, after seven years of uninterrupted growth, due to heavy rainfall.
The Florida brown tides
The first brown tide in Florida began during the summer of 2012 and collapsed a few months thereafter, and the second brown tide began in the spring of 2013 and collapsed in mid-summer 2013. During the brown tides in Florida, A. lagunensis consisted of 98% of the phytoplankton community with abundances greater than 2 x 106 cells/mL. Similar to the causes of the Texas brown tides, the Florida brown tides were proliferated by high salinity, low grazing pressure, high dissolved organic nitrogen and low inorganic nutrients, and competitive advantage over other phytoplankton. However, these brown tides were short-lived compared to that in Texas, lasting no more than a few months.
The Cuba brown tide
In January 2013, A. lagunensis populations sharply increased in Guantanamo Bay, sparking a brown tide in Cuba. This in turn led to many shutdowns of the plant which supplied freshwater to the US Naval Base in Guantanamo Bay. Similar to the Florida brown tides, this A. lagunensis bloom was short lived compared to that in Texas, only lasting from January 2013 to November 2013. Unlike the Florida and Texas brown tides, hypersalinity was not found in the Caribbean waters where A. lagunensis bloomed. In the Texas and Florida brown tides, high primary productivity was always correlated with high A. lagunensis density, but in Cuba high primary productivity correlated with high A. lagunensis density only initially. After some time, productivity in Cuba remained high, but the dominant phytoplankton shifted from A. lagunensis to Synechococcus sp..
Competitive advantages
Aureoumbra lagunensis has competitive advantages that may allow it to persist in unfavourable marine environments such as low light intensities, nutrient limitations and high temperatures. A. lagunensis has an encapsulating mucus layer of exopolymer secretions (EPS) and is able to revert from vegetative to resting cell forms in unfavorable conditions. Allelopathic effects have also been observed that can cause cell lysis, reduced growth rates and reduced photosynthetic efficiency of co-existing phytoplankton. A. lagunensis experiences low mortality losses via its ability to discourage grazing by zooplankton and filter-feeding mollusks. Positive feedback involved in A. lagunensis’ ability to grow competitively in low-nutrient environments and low light levels and its ability to discourage grazing further contributes to brown tide blooms.
The EPS layer
The adhesive EPS layer surrounding A. lagunensis reduces grazing by hypotrichous filter-feeding protozoans such as Aspidisca sp and Euplotes, as marked by these protozoan's reduction in growth rate with increasing levels of EPS coating. It is speculated that the effects on grazing may be caused by the adherence of the exopolymer to cilia on the surface of protozoans thus affecting swimming abilities and clogging feeding apparatus, both of which may decrease grazing efficiency.
With increasing salinity, the EPS layer of A. lagunensis increases. It has been hypothesized that with the hypersaline conditions of Laguna Madre during the bloom, A. lagunensis was able to out-compete other organisms due to a reduction in grazing pressure, which allowed it to thrive and further contribute to the Texas Brown Tide.
The polysaccharide sheath is hypothesized to protect A. lagunensis from being digested in the guts of some zooplankton like that of the copepod Acartia tonsa as viable cells can be detected in its fecal pellets.
Vegetative and resting cell forms
Aureoumbra lagunensis has vegetative and resting cell forms in response to optimal conditions and environmental stressors respectively. Such a capability allows this organism to tolerate nutrient limitations, temperature fluctuations and light intensity variations. Relative to the vegetative form of A. lagunensis, the resting cell is larger, more round, has fewer and more aggregated plastids, lower chlorophyll A concentrations, decreased respiration rates and growth rates, reduced photosynthetic efficiency, greater vacuolar space and lower RNA:DNA ratio due to a decrease in RNA content but not DNA content. Red accumulation bodies have also been observed in resting cells but not vegetative cells. Such accumulation bodies are associated with increased sterol concentrations. Vegetative cells are described as irregularly shaped and containing sterols characterized as (E)-24-propylidenecholesterol, stigmasterol, sitosterol, cholesterol, (24R)-24-propylcholesterol with trace amounts of 24-methylenecholesterol, crinosterol, clerosterol, campesterol, dihydrobrassicasterol, and 24-isopropylcholesterol.
Loss of biodiversity
Brown tides caused by A. lagunensis lead to substantial light attenuation, a loss in intensity of light travelling to the bottom of water. In the Texas Brown tide, the increase in light attenuation caused a decrease in seagrass beds which was abundant prior to the brown tide. This contributed to a loss in biomass in terms of primary producers and in turn the diversity of benthic invertebrates in Laguna Madre. The benthic phototrophs compete with A. lagunensis for nutrients, especially those regenerated in sediments, an important source of recycled nutrient in shallow lagoons that host these blooms. As a result, decrease in benthic biomass further contributes to the dispersion of benthic nutrient input to overlying water, fueling bloom development and causing more severe shading of the bottom water which further limits the growth of benthic phototrophs.
Aureoumbra lagunensis favors a low light environment, thus an increase in light attenuation results in an increase in Aureoumbra populations on surface water which causes more severe shading. A. lagunensis could discourage grazing of zooplankton and filter-feeding mollusks to increase the chance of its survival. Brown tide blooms caused by A. lagunensis decrease the grazing activity, growth and egg release rates of the initially abundant mesozooplankton Acartia tonsa. The dominant clam, Mulinia lateralis, also experienced population declines during the Texas brown tide bloom, however, this decrease in abundance was initiated before the beginning of the bloom. In addition to Mulinia lateralis, the dominant polychaete, Streblospio Benedict, an important grazer of phytoplankton, also decreased in abundance.
Nitrogen uptake
Aureoumbra lagunensis are not able to use nitrate (NO3−) as a sole source of nitrogen and instead utilize inorganic nitrogen in the form of ammonium (NH4+) and nitrite (NO2−) and organic nitrogen in the form of urea.
Aureoumbra lagunensis is found in high abundance where there is high organic to inorganic nitrogen ratios but growth rates of A. lagunensis are greater when grown with ammonium than urea. Collectively, ammonium and urea make up more than 90% of nitrogen uptake in bloom populations. A. lagunensis has higher affinity for and greater productivity with low levels of organic and inorganic nitrogen as opposed to high levels such that they are unable to increase growth rates in high ammonium concentrations (≈40 μM) which can ultimately cause them to be out-competed by Synechococcus species which thrive in such conditions. Low levels of ammonium (≈10uM) has been shown to enhance growth rates of A. lagunensis to a greater degree than phycoerythrin-containing cyanobacteria.
Aureoumbra lagunensis is more productive when utilizing NH4+ or NO2− than with NO3−. A. lagunensis’ inability to use NO3− as the sole source of nitrogen is maintained when samples are supplied with iron and other trace metals. When nitrate is in excess the effects on A. lagunensis can be detrimental as it has been found that phycocyanin-containing cyanobacteria can thrive in such environments causing for an increase in its abundance and a decline in A. lagunensis abundance.
Baffin Bay, Texas has seasonally and yearly stable levels of organic and inorganic nitrogen; however, when the large fish die-off occurred in 1990 due to severe freezing, more urea and ammonium became available to A. lagunensis, thus potentially initiating the brown tide.
Phosphorus uptake
Aureoumbra lagunensis blooms at a low phosphorus concentration. It has the ability to regenerate phosphate from environmental dissolved organic phosphorus (DOP), a significant part of marine total dissolved phosphorus pool. It could use DOP as the sole source of phosphate for growth as a result.
The mechanisms of phosphate acquisition in A. lagunensis remain unconfirmed, but it is hypothesized that A. lagunensis uses a common phosphorus-limitation specific protein, alkaline phosphatase, to dephosphorylate DOP compounds to alleviate the low phosphate bioavailability. High alkaline phosphatase activity accompanied with very low dissolved inorganic phosphorus concentration were measured in the A. lagunensis populations in the Texas Brown Tide at Laguna Madre.
Aureoumbra lagunensis is capable of growing under a wide range of N:P ratios, but forms dense blooms when the water column N:P ratio increases to high levels (≈140). In cultures, A.lagunensis have a C:P ratio greater than 2000 when grown under severe phosphorus limiting environment.
Chloroplast genome
The chloroplast genome is non-circular. Strain CCMP1507 has a chloroplast genome size of 94,346 bp, encoding 110 proteins and containing 10 tandem repeats, 8 of which are adjacent to photosynthetic and energy production genes. The genome lacks large inverted repeats commonly found in chloroplast.
Although A. lagunensis is similar to A. anophagefferens, it contains five chloroplast genes , and light independent chlorophyll biosynthesis genes chlL, chlN, and chlB which are not present in A. anophagefferens’ chloroplast genome. It is speculated that the presence of the light independent genes for chlorophyll biosynthesis is what allows A.lagunensis to persist in low light intensities.
References
Ochrophyta
Ochrophyte species
Protists described in 1997 | Aureoumbra lagunensis | [
"Biology"
] | 3,178 | [
"Ochrophyta",
"Algae"
] |
58,447,310 | https://en.wikipedia.org/wiki/Aspergillus%20multicolor | Aspergillus multicolor is a species of fungus in the genus Aspergillus. It is from the Nidulantes section. The species was first described in 1954. It was isolated from forest soil in Somalia. It has been shown to produce asticolourin A-C, averufin, 5,6-dimethoxydihydrosterigmatocystin, 5,6-dimethoxysterigmatocystin, sterigmatocystin, and versicolourin C.
In 2016, the genome of A. multicolor was sequenced as a part of the Aspergillus whole-genome sequencing project - a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 35.25 Mbp.
Growth and morphology
Aspergillus multicolor has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
multicolor
Fungi described in 1954
Fungus species | Aspergillus multicolor | [
"Biology"
] | 240 | [
"Fungi",
"Fungus species"
] |
58,447,392 | https://en.wikipedia.org/wiki/Aspergillus%20olivicola | Aspergillus olivicola is a species of fungus in the genus Aspergillus. It is from the Nidulantes section. The species was first described in 2008. It has been isolated from fruit in Italy. A. olivicola has been shown to produce aflatoxin B1, emericellin, shamixanthone, siderin, sterigmatocystin, terrein, and varitriol.
In 2016, the genome of A. olivicola was sequenced as a part of the Aspergillus whole-genome sequencing project - a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 33.17 Mbp.
Growth and morphology
Aspergillus olivicola has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
olivicola
Fungi described in 2008
Fungus species | Aspergillus olivicola | [
"Biology"
] | 226 | [
"Fungi",
"Fungus species"
] |
58,447,425 | https://en.wikipedia.org/wiki/Aspergillus%20recurvatus | Aspergillus recurvatus is a species of fungus in the genus Aspergillus. It is from the Nidulantes section. The species was first described in 1965.
In 2016, the genome of A. recurvatus was sequenced as a part of the Aspergillus whole-genome sequencing project - a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 30.72 Mbp.
Growth and morphology
Aspergillus recurvatus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
recurvatus
Fungi described in 1965
Fungus species | Aspergillus recurvatus | [
"Biology"
] | 171 | [
"Fungi",
"Fungus species"
] |
58,447,447 | https://en.wikipedia.org/wiki/Aspergillus%20stella-maris | Aspergillus stella-maris is a species of fungus in the genus Aspergillus. It is from the Nidulantes section. The species was first described in 2008. A. stella-maris has been reported to produce emericellin and shamixanthone. It has star-shaped ascospores.
The genome of A. stella-maris was in 2016 sequenced as a part of the Aspergillus whole-genome sequencing project - a project dedicated to performing whole-genome sequencing of all members of the Aspergillus genus. The genome assembly size was 34.00 Mbp.
Growth and morphology
Aspergillus stella-maris has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
stella-maris
Fungi described in 2008
Fungus species | Aspergillus stella-maris | [
"Biology"
] | 196 | [
"Fungi",
"Fungus species"
] |
58,447,485 | https://en.wikipedia.org/wiki/Aspergillus%20undulatus | Aspergillus undulatus is a species of fungus in the genus Aspergillus. It is from the Nidulantes section. The species was first described in 1985. A. undulatus has been isolated in China and Germany.
In 2016, the genome of A. undulatus was sequenced as a part of the Aspergillus whole-genome sequencing project - a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 32.11 Mbp.
Growth and morphology
Aspergillus undulatus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
undulatus
Fungi described in 1985
Fungus species | Aspergillus undulatus | [
"Biology"
] | 180 | [
"Fungi",
"Fungus species"
] |
58,447,564 | https://en.wikipedia.org/wiki/Aspergillus%20venezuelensis | Aspergillus venezuelensis is a species of fungus in the genus Aspergillus. It is from the Nidulantes section. The species was first described in 2004. It has been shown to produce aflatoxin B1 and sterigmatocystin.
In 2016, the genome of A. venezuelensis was sequenced as a part of the Aspergillus whole-genome sequencing project - a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 34.84 Mbp.
Growth and morphology
Aspergillus venezuelensis has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
venezuelensis
Fungi described in 2004
Fungus species | Aspergillus venezuelensis | [
"Biology"
] | 194 | [
"Fungi",
"Fungus species"
] |
58,447,678 | https://en.wikipedia.org/wiki/Aspergillus%20ochraceoroseus | Aspergillus ochraceoroseus is a species of fungus in the genus Aspergillus. It is from the Ochraceorosei section. The species was first described in 1979. It has been isolated from soil in the Tai National Forest in the Ivory Coast. It has been shown to produce aflatoxin and sterigmatocystin.
In 2014, the genome of A. ochraceoroseus was sequenced as a part of the Aspergillus whole-genome sequencing project - a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 27.72 Mbp.
Growth and morphology
Aspergillus ochraceoroseus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
ochraceoroseus
Fungi described in 1979
Fungus species | Aspergillus ochraceoroseus | [
"Biology"
] | 209 | [
"Fungi",
"Fungus species"
] |
58,447,715 | https://en.wikipedia.org/wiki/Aspergillus%20insolitus | Aspergillus insolitus is a species of fungus in the genus Aspergillus. It is from the Polypaecilum section. The species was first described in 2014. The genome of A. insolitus was in 2016 sequenced as a part of the Aspergillus whole-genome sequencing project - a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 23.18 Mbp.
Growth and morphology
A. insolitus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
insolitus
Fungi described in 2014
Fungus species | Aspergillus insolitus | [
"Biology"
] | 166 | [
"Fungi",
"Fungus species"
] |
58,447,785 | https://en.wikipedia.org/wiki/Aspergillus%20robustus | Aspergillus robustus is a species of fungus in the genus Aspergillus. It has phototropic conidiophores. The species was first described in 1978. The genome of A. robustus was in 2016 sequenced as a part of the Aspergillus whole-genome sequencing project - a project dedicated to performing whole-genome sequencing of all members of the Aspergillus genus. The genome assembly size was 33.14 Mbp.
Growth and morphology
Aspergillus robustus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
robustus
Fungi described in 1978
Fungus species | Aspergillus robustus | [
"Biology"
] | 163 | [
"Fungi",
"Fungus species"
] |
58,447,873 | https://en.wikipedia.org/wiki/Elizabeth%20Bradley%20%28mathematician%20and%20rower%29 | Elizabeth Bradley (born April 9, 1961) is an American applied mathematician and computer scientist, and a former Olympic rower. She is a professor of computer science at the University of Colorado Boulder, where she specializes in nonlinear systems and nonlinear time series analysis.
Rowing
Bradley competed in the women's coxed four event at the 1988 Summer Olympics, with rowers Jennifer Corbet, Cynthia Eckert, and Sarah Gengler, and coxswain Kim Santiago. Their boat placed fifth out of the ten boats competing in the event.
She also competed in the 1986 World Rowing Championships, placing fourth in women's eights, and in the 1987 World Rowing Championships, placing fourth in women's pairs.
Education and academic career
Bradley was a student at the Massachusetts Institute of Technology, where she earned a bachelor's degree in electrical engineering in 1983, a master's degree in computer science in 1986, and a Ph.D. in electrical engineering and computer science in 1992. Her dissertation, Taming Chaotic Circuits, was jointly supervised by Hal Abelson and Gerald Jay Sussman.
She joined the University of Colorado computer science department as an assistant professor in 1993, chaired the department from 2003 to 2006, and was promoted to full professor in 2004. She has also visited Harvard University, and was a Radcliffe fellow at the Radcliffe Institute for Advanced Study for 2006–2007 as well as a Packard Fellow in Science and Engineering in 1995.
She was named a CRA-W Distinguished Professor by the Committee on Widening Participation in Computing Research in 2008, and was named a President's Teaching Scholar by the University of Colorado in 2017.
References
External links
Home page
1961 births
Living people
American female rowers
Olympic rowers for the United States
Rowers at the 1988 Summer Olympics
Rowers from New York City
20th-century American mathematicians
21st-century American mathematicians
21st-century American women mathematicians
American applied mathematicians
Dynamical systems theorists
American computer scientists
American women computer scientists
University of Colorado Boulder faculty
Radcliffe fellows
20th-century American women scientists
21st-century American women scientists
MIT School of Engineering alumni
20th-century American sportswomen | Elizabeth Bradley (mathematician and rower) | [
"Mathematics"
] | 423 | [
"Dynamical systems theorists",
"Dynamical systems"
] |
58,448,044 | https://en.wikipedia.org/wiki/Aspergillus%20cavernicola | Aspergillus cavernicola (also named A. amylovorus) is a species of fungus in the genus Aspergillus. It is from the Cavernicolus section. The species was first described in 1969. It has been isolated from the wall of a cave in Romania and from wheat starch in Ukraine.
Growth and morphology
A. cavernicola has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
cavernicola
Fungi described in 1969
Fungus species | Aspergillus cavernicola | [
"Biology"
] | 134 | [
"Fungi",
"Fungus species"
] |
58,448,091 | https://en.wikipedia.org/wiki/Aspergillus%20albertensis | Aspergillus albertensis is a species of fungus in the genus Aspergillus. It is from the Flavi section. The species was first described in 1985. It was isolated from a human ear in Canada. A. albertensis has been shown to produce ochratoxin A and B. It forms yellow spores.
Growth and morphology
A. albertensis has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
albertensis
Fungi described in 1985
Fungus species | Aspergillus albertensis | [
"Biology"
] | 133 | [
"Fungi",
"Fungus species"
] |
58,448,142 | https://en.wikipedia.org/wiki/Aspergillus%20tamarii | Aspergillus tamarii is a species of fungus in the genus Aspergillus. It is from the Flavi section. The species was first described in 1913. A. tamarii has been used in the production of soy sauce. It has been isolated from soil in the United States.
Growth and morphology
A. tamarii has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
tamarii
Fungi described in 1913
Fungus species | Aspergillus tamarii | [
"Biology"
] | 129 | [
"Fungi",
"Fungus species"
] |
58,448,190 | https://en.wikipedia.org/wiki/Aspergillus%20arachidicola | Aspergillus arachidicola is a species of fungus in the genus Aspergillus. It is from the Flavi section. The species was first described in 2008. A. arachidicola has been shown to produce aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, aspergillic acid, chrysogine, kojic acid, parasiticolide, and ditryphenaline.
Growth and morphology
A. arachidicola has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
arachidicola
Fungi described in 2008
Fungus species | Aspergillus arachidicola | [
"Biology"
] | 167 | [
"Fungi",
"Fungus species"
] |
58,448,253 | https://en.wikipedia.org/wiki/Aspergillus%20avenaceus | Aspergillus avenaceus is a species of fungus in the genus Aspergillus. It is from the Flavi section. The species was first described in 1943. A. avenaceus has been isolated in the UK from a Pisum sativum seed, and in the United States. It has been reported to produce avenaciolide and aspirochlorine.
Growth and morphology
A. avenaceus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
avenaceus
Fungi described in 1943
Fungus species | Aspergillus avenaceus | [
"Biology"
] | 148 | [
"Fungi",
"Fungus species"
] |
58,448,312 | https://en.wikipedia.org/wiki/Aspergillus%20bertholletius | Aspergillus bertholletius is a species of fungus in the genus Aspergillus. It is from the Flavi section. The species was first described in 2012. It has been isolated from Brazil nuts (Bertholletia excelsa).
Growth and morphology
A. bertholletius has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
bertholletius
Fungi described in 2012
Fungus species | Aspergillus bertholletius | [
"Biology"
] | 123 | [
"Fungi",
"Fungus species"
] |
58,448,565 | https://en.wikipedia.org/wiki/Aspergillus%20caelatus | Aspergillus caelatus is a species of fungus in the genus Aspergillus. It is from the Flavi section. The species was first described in 1997. It has been isolated from soil in the United States.
Growth and morphology
A. caelatus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
caelatus
Fungi described in 1997
Fungus species | Aspergillus caelatus | [
"Biology"
] | 115 | [
"Fungi",
"Fungus species"
] |
58,448,597 | https://en.wikipedia.org/wiki/Aspergillus%20coremiiformis | Aspergillus coremiiformis is a species of fungus in the genus Aspergillus. It is from the Flavi section. The species was first described in 1979. It has been shown to produce indol alkaloids.
Growth and morphology
A. coremiiformis has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
coremiiformis
Fungi described in 1979
Fungus species | Aspergillus coremiiformis | [
"Biology"
] | 119 | [
"Fungi",
"Fungus species"
] |
65,158,329 | https://en.wikipedia.org/wiki/Blaschke%20sum | In convex geometry and the geometry of convex polytopes, the Blaschke sum of two polytopes is a polytope that has a facet parallel to each facet of the two given polytopes, with the same measure. When both polytopes have parallel facets, the measure of the corresponding facet in the Blaschke sum is the sum of the measures from the two given polytopes.
Blaschke sums exist and are unique up to translation, as can be proven using the theory of the Minkowski problem for polytopes. They can be used to decompose arbitrary polytopes into simplices, and centrally symmetric polytopes into parallelotopes.
Although Blaschke sums of polytopes are used implicitly in the work of Hermann Minkowski, Blaschke sums are named for Wilhelm Blaschke, who defined a corresponding operation for smooth convex sets. The Blaschke sum operation can be extended to arbitrary convex bodies, generalizing both the polytope and smooth cases, using measures on the Gauss map.
Definition
For any -dimensional polytope, one can specify its collection of facet directions and measures by a finite set of -dimensional nonzero vectors, one per facet, pointing perpendicularly outward from the facet, with length equal to the -dimensional measure of its facet. As Hermann Minkowski proved, a finite set of nonzero vectors describes a polytope in this way if and only if it spans the whole -dimensional space, no two are collinear with the same sign, and the sum of the set is the zero vector. The polytope described by this set has a unique shape, in the sense that any two polytopes described by the same set of vectors are translates of each other.
The Blaschke sum of two polytopes and is defined by combining the vectors describing their facet directions and measures, in the obvious way: form the union of the two sets of vectors, except that when both sets contain vectors that are parallel and have the same sign, replace each such pair of parallel vectors by its sum. This operation preserves the necessary conditions for Minkowski's theorem on the existence of a polytope described by the resulting set of vectors, and this polytope is the Blaschke sum. The two polytopes need not have the same dimension as each other, as long as they are both defined in a common space of high enough dimension to contain both: lower-dimensional polytopes in a higher-dimensional space are defined in the same way by sets of vectors that span a lower-dimensional subspace of the higher-dimensional space, and these sets of vectors can be combined without regard to the dimensions of the spaces they span.
For convex polygons and line segments in the Euclidean plane, their Blaschke sum coincides with their Minkowski sum.
Decomposition
Blaschke sums can be used to decompose polytopes into simpler polytopes. In particular, every -dimensional convex polytope with facets can be represented as a Blaschke sum of at most simplices (not necessarily of the same dimension). Every -dimensional centrally symmetric convex polytope can be represented as a Blaschke sum of parallelotopes. And every -dimensional convex polytope can be represented as a Blaschke sum of -dimensional convex polytopes, each having at most facets.
Generalizations
The Blaschke sum can be extended from polytopes to arbitrary bounded convex sets, by representing the amount of surface in each direction using a measure on the Gauss map of the set instead of using a finite set of vectors, and adding sets by adding their measures. If two bodies of constant brightness are combined in this way, the result is another body of constant brightness.
Kneser–Süss inequality
The volume of the Blaschke sum of two -dimensional polytopes or convex bodies and obeys an inequality known as the Kneser–Süss inequality, an analogue of the Brunn–Minkowski theorem on volumes of Minkowski sums of convex bodies:
References
Convex geometry
Polytopes
Binary operations | Blaschke sum | [
"Mathematics"
] | 871 | [
"Binary operations",
"Mathematical relations",
"Binary relations"
] |
65,160,294 | https://en.wikipedia.org/wiki/Henry%20Cort%20Harold%20Carpenter | Sir Henry Cort Harold Carpenter (6 February 1875 – 13 September 1940) was a British metallurgist and specialist on steels. He made pioneering studies on the crystallization of metals and the study of their properties.
Carpenter was born in Clifton, Bristol to William Lant Carpenter and Annie Grace Viret. His ancestors included William Benjamin Carpenter and the metallurgist Henry Cort. After the death of his father, he was taken care of by his uncle Joseph Estlin Carpenter. He studied at St. Paul's School and then at Eastbourne College. He studied chemistry at Merton College, Oxford, graduating in 1896 and then went to study organic chemistry in Leipzig, gaining a Ph.D there. He returned to assist W.H. Perkin at Owens College, Manchester.
In 1902 he joined the National Physical Laboratory and worked on chemical and metallurgical problems. Along with B.F.E. Keeling he worked on steel alloys. In 1906 he was head of metallurgy at Victoria University, Manchester. In 1914 he joined the Royal School of Mines at Imperial College, South Kensington as Professor of Metallurgy. He was President of the Iron and Steel Institute (1935–1937) and the Institution of Mining and Metallurgy.
Carpenter was elected Fellow of the Royal Society in 1918 and knighted in the 1929 Birthday Honours. He was awarded the Bessemer Gold Medal in 1931 by the Iron and Steel Institute.
He married Ethel Mary Lomas in 1905. He was found dead from drowning in a stream after suffering a heart attack while out walking alone in the Clyne valley, Swansea.
References
External links
Obituaries
1875 births
1940 deaths
People from Clifton, Bristol
People educated at Eastbourne College
Alumni of Merton College, Oxford
British metallurgists
Fellows of the Royal Society
Bessemer Gold Medal | Henry Cort Harold Carpenter | [
"Chemistry"
] | 371 | [
"Bessemer Gold Medal",
"Chemical engineering awards"
] |
65,161,632 | https://en.wikipedia.org/wiki/Trans%20fat | Trans fat is a type of unsaturated fat that occurs in foods. Small amounts of trans fats occur naturally, but large amounts are found in some processed foods made with partially hydrogenated oils. Because consumption of trans fats is associated with increased risk for cardiovascular diseases, artificial trans fats are highly regulated or banned in many countries. However, they are still widely consumed in developing nations where they are associated with increased risk of diabetes, cardiovascular diseases, and death.
In 2015, the US Food and Drug Administration (FDA) stated that artificial trans fats from partially hydrogenated oils were not generally recognized as safe (GRAS), and the use of such oils and trans fats should be limited or eliminated from manufactured foods. Numerous countries, including the European Union, Canada, and Australia/New Zealand, followed with restrictions or bans on the use of partially hydrogenated oils and trans fats in food manufacturing. The World Health Organization (WHO) had set a goal to make the world free from industrially produced trans fat by the end of 2023. The goal was not met, and the WHO announced another goal in 2024 "for accelerated action till 2025 to complete this effort".
Trans fatty acids (also called trans-unsaturated fatty acids) are derived from trans fats, which are triglycerides (esters of glycerin). Trans fats are converted to trans fatty acids in the digestive tract prior to absorption.
Occurrence
Trans fats occur naturally in the fats of products made from ruminant animals, such as cheese or butter, and some are used in manufactured foods, such as cooking oils or margarine.
Naturally-occurring trans fats
Trans fats occur in meat and dairy products from ruminants. For example, butter contains about 3% trans fat by weight. These naturally occurring trans fats include conjugated linoleic acid (CLA) and vaccenic acid. They arise from the action of bacteria in the rumen. Polyunsaturated fats are toxic to the rumen-based bacteria, which detoxify the fats by changing some cis-double bonds to trans-double bonds. In contrast to industrially produced trans fats, this bacterial process produces only a few specific isomers. As industrial sources of trans fats are eliminated, increased attention focuses on ruminant derived trans fats.
Small amounts of trans fats occur in meat and milk fat.
Hydrogenation
Trans fat can be an unintentional byproduct of the industrial processing of oils. Unlike naturally derived trans fats, the trans fats that result from hydrogenation consist of many isomers. In food production, liquid cis-unsaturated fats such as vegetable oils are hydrogenated to produce more saturated fats, which have desirable properties:
The shelf life of fats correlates with the degree of saturation: polyunsaturated fats are prone to autoxidation whereas saturated fats, being virtually inert in air, have very long shelf lives.
Saturated fats tend to be more solid at room temperature. This property is important for margarine, one of the original uses for fat hydrogenation.
However, an isomerization side reaction during fat hydrogenation can convert remaining unsaturated fats to the thermodynamically-favored trans isomer.
A number of old and new ingredients are available to replace partially-hydrogenated oil containing significant levels of trans fat. These include partially-hydrogenated oil made with improved processes, plant oils rich in monounsaturated fats and saturated fats, and a mix of fats combined with interesterification. The technology has improved such that a 2021 review indicates that trans fat from hydrogenated fats is no longer a problem in modern countries.
Thermal isomerization
When heated (cooked), some unsaturated fats change from their normal geometry to trans. The rate of isomerization is accelerated by free radicals.
History
There were suggestions in the scientific literature as early as 1956 that trans fats could cause an increase in coronary artery disease. Studies in the early 1990s brought renewed scrutiny and confirmation of the negative health impact of trans fats. In 1994, it was estimated that trans fats caused at least 20,000 deaths annually in the U.S. from heart disease. In the 1990s, activists such as CSPI that had promoted trans fat safety began arguing that trans fats should be disclosed on product labels and menus. Several lawsuits were launched against high-visibility restaurants and food manufacturers with the objective of supporting a broader phase-out of trans fats.
Mandatory food labeling was introduced in several countries and Denmark was first to mandate limits on industrially-produced trans fats in 2004. In January 2007, faced with the prospect of an outright ban on the sale of their product, Crisco was reformulated to meet the U.S. Food and Drug Administration (FDA) definition of "zero grams trans fats per serving" (that is less than one gram per tablespoon, or up to 7% by weight; or less than 0.5 grams per serving size) by boosting the saturation and then diluting the resulting solid fat with unsaturated vegetable oils. Noting that elimination of industrially produced trans fat is feasible and achievable, the World Health Organization (WHO) has set a goal to make the world free from industrially produced trans fat by the end of 2023. By the end of 2021, the WHO announced that 40 countries had implemented industrial trans fat elimination policies that "are protecting 1.4 billion people from this deadly food compound" but that 10 of the 15 countries suffering the highest health impacts from trans fats had not yet adopted a policy.
Structure
A fatty acid is characterized as either saturated or unsaturated based on the respective absence or presence of C=C double bonds in its backbone. If the molecule contains no double C=C bonds, it is said to be saturated; otherwise, it is unsaturated to some degree.
The C=C double bond is rotationally rigid. If the hydrogen bonded to each of the carbons in this double bond are on the same side, this is called cis, and leads to a bent molecular chain. If the two hydrogens are on opposite sides, this is called trans, and leads to a straight chain.
Because trans fats are more linear, they crystallize more easily, allowing them to be solid (rather than liquid) at room temperatures. This has several processing and storage advantages.
In nature, unsaturated fatty acids generally have cis configurations as opposed to trans configurations. Saturated fatty acids (those without any carbon-carbon double bonds) are abundant (see tallow), but they also can be generated from unsaturated fats by the process of fat hydrogenation. In the course of hydrogenation, some cis double bonds convert into trans double bonds. Chemists call this conversion an isomerization reaction.
The same molecule, containing the same number of atoms, with a double bond in the same location, can be either a trans or a cis fatty acid depending on the configuration of the double bond. For example, oleic acid and elaidic acid are both unsaturated fatty acids with the chemical formula C9H17C9H17O2. They both have a double bond located midway along the carbon chain. It is the configuration of this bond that sets them apart. The configuration has implications for the physical-chemical properties of the molecule. The trans configuration is straighter, while the cis configuration is noticeably kinked as can be seen from the three-dimensional representation shown above. Cis- and trans fatty acids (and their derivatives) have distinct chemical (and metabolic) properties, For example, the melting point of elaidic acid is 45 °C higher than that of oleic acid. This notably means that it is a solid at human body temperatures.
Hydrogenation as a source of trans fats
{{main|Fat hydrogenation]]
The hydrogenation process was widely adopted by the food industry in the early 1900s; first for the production of margarine, a replacement for butter and shortening, and eventually for various other fats used in snack food, packaged baked goods, and deep fried products.
Full hydrogenation of a fat or oil produces a fully saturated fat. For food purposes, hydrogenation generally is not allowed to go to completion. The main target is a specific melting point and hardness, and this fine-tuning requires that some unsaturation remain. This partial hydrogenation turns some of the cis double bonds into trans bonds by an isomerization reaction. This side reaction accounts for most of the trans fatty acids consumed today, by far.
The standard 140 kPa (20 psi) process of hydrogenation produces a product of about 40% trans fatty acid by weight, compared to about 17% using higher pressures of hydrogen. Blended with unhydrogenated liquid soybean oil, the high-pressure-processed oil produced margarine containing 5 to 6% trans fat. Based on current U.S. labeling requirements (see below), the manufacturer could claim the product was free of trans fat. The level of trans fat may also be altered by modification of the temperature and the length of time during hydrogenation.
The trans fat levels can be quantified using various forms of chromatography.
Presence in food
Animal fats
trans fatty acids (TFAs) occur in small amounts in meat and milk of ruminants (such as cattle and sheep), typically 2–5% of total fat. Natural TFAs, which include conjugated linoleic acid (CLA) and vaccenic acid, originate in the rumen of these animals. CLA has two double bonds, one in the cis configuration and one in trans, which makes it simultaneously a cis- and a trans-fatty acid.
A type of trans fat occurs naturally in the milk and body fat of ruminants (such as cattle and sheep) at a level of 2–5% of total fat. Natural trans fats, which include conjugated linoleic acid (CLA) and vaccenic acid, originate in the rumen of these animals. CLA has two double bonds, one in the cis configuration and one in trans, which makes it simultaneously a cis- and a trans-fatty acid.
The US National Dairy Council has asserted that the trans fats present in foods of animal origin are of a different type than those in partially hydrogenated oils, and do not appear to exhibit the same negative effects. A scientific review agrees with the conclusion (stating that "the sum of the current evidence suggests that the Public health implications of consuming trans fats from ruminant products are relatively limited") but cautions that this may be due to the low consumption of trans fats from animal sources compared to artificial ones.
Despite this concern, the NAS dietary recommendations have not included eliminating trans fat from the diet. This is because trans fat is naturally present in many animal foods in trace quantities, and thus its removal from ordinary diets might introduce undesirable side effects and nutritional imbalances if proper nutritional planning is not undertaken. The NAS has, thus, "recommended that trans fatty acid consumption be as low as possible while consuming a nutritionally adequate diet". Like the NAS, the World Health Organization has tried to balance public health goals with a practical level of trans fat consumption, recommending in 2003 that trans fats be limited to less than 1% of overall energy intake.
A meta-analysis showed that all trans fats, regardless of natural or artificial origin equally raise LDL and lower HDL levels. Other studies though have shown different results when it comes to animal based trans fats like conjugated linoleic acid (CLA). Although CLA is known for its anticancer properties, researchers have also found that the cis-9, trans-11 form of CLA can reduce the risk for cardiovascular disease and help fight inflammation.
Natural "trans fats" in dairy products
Some trans fatty acids occur in natural fats and traditionally processed foods. Vaccenic acid occurs in breast milk, and some isomers of conjugated linoleic acid (CLA) are found in meat and dairy products from ruminants. Butter, for example, contains about 3% trans fat.
The U.S. National Dairy Council has asserted that the trans fats present in animal foods are of a different type than those in partially hydrogenated oils, and do not appear to exhibit the same negative effects. A review agrees with the conclusion (stating that "the sum of the current evidence suggests that the Public health implications of consuming trans fats from ruminant products are relatively limited") but cautions that this may be due to the low consumption of trans fats from animal sources compared to artificial ones.
In 2008 a meta-analysis found that all trans fats, regardless of natural or artificial origin equally raise LDL and lower HDL levels. Other studies though have shown different results when it comes to animal-based trans fats like conjugated linoleic acid (CLA). Although CLA is known for its anticancer properties, researchers have also found that the cis-9, trans-11 form of CLA can reduce the risk for cardiovascular disease and help fight inflammation.
Processed foods
Partially hydrogenated vegetable oils were an increasingly significant part of the human diet for about 100 years, especially after 1950 as processed food rose in popularity.
Animal-based fats were once the only trans fats consumed, but by far the largest amount of trans fat consumed today is created by the processed food industry as a side effect of partially hydrogenating unsaturated plant fats (generally vegetable oils). These partially hydrogenated fats have displaced natural solid fats and liquid oils in many areas, the most notable ones being in the fast food, snack food, fried food, and baked goods industries.
Up to 45% of the total fat in those foods containing human-made trans fats formed by partially hydrogenating plant fats may be trans fat. An analysis of some industrialized foods in 2006 found up to 30% "trans fats" in artificial shortening, 10% in breads and cake products, 8% in cookies and crackers, 4% in salty snacks, 7% in cake frostings and sweets, and 26% in margarine and other processed spreads. Another 2010 analysis however found only 0.2% of trans fats in margarine and other processed spreads.
Shortenings
Shortenings, because they are widely used, are of particular concern. Baking shortenings, unless reformulated, contain around 30% trans fats compared to their total fats. High-fat dairy products such as butter contain about 4%. Margarines not reformulated to reduce trans fats may contain up to 15% trans fat by weight, but some reformulated ones are less than 1% trans fat. Shortenings for deep-frying in restaurants can be used for longer than most conventional oils before becoming rancid. In the early 21st century, non-hydrogenated vegetable oils that have lifespans exceeding that of the frying shortenings became available. In fast-food chains, trans fat levels in fast food can vary with location. For example, an analysis of samples of McDonald's French fries collected in 2004 and 2005 found that fries served in New York City contained twice as much trans fat as in Hungary, and 28 times as much as in Denmark, where trans fats are restricted. At KFC, the pattern was reversed, with Hungary's product containing twice the trans fat of the New York product. Even within the U.S. there was variation, with fries in New York containing 30% more trans fat than those from Atlanta.
High levels of TFAs have been recorded in popular "fast food" meals. An analysis of samples of McDonald's French fries collected in 2004 and 2005 found that fries served in New York City contained twice as much trans fat as in Hungary, and 28 times as much as in Denmark, where trans fats are restricted. For Kentucky Fried Chicken products, the pattern was reversed: the Hungarian product containing twice the trans fat of the New York product. Even within the United States, there was variation, with fries in New York containing 30% more trans fat than those from Atlanta.
Breast milk
It has been established that trans fats in human breast milk fluctuate with maternal consumption of trans fat, and that the amount of trans fats in the bloodstream of breastfed infants fluctuates with the amounts found in their milk. In 1999, reported percentages of trans fats (compared to total fats) in human milk ranged from 1% in Spain, 2% in France, 4% in Germany, and 7% in Canada and the U.S.
Regulatory action
In the last few decades, there has been substantial amount of regulation in many countries, limiting trans fat contents of industrialized and commercial food products.
In light of recognized evidence and scientific agreement, nutritional authorities consider all trans fats equally harmful for health and recommend that their consumption be reduced to trace amounts. In 2003, the WHO recommended that trans fats make up no more than 0.9% of a person's diet and, in 2018, introduced a 6-step guide to eliminate industrially-produced trans-fatty acids from the global food supply.
The National Academy of Sciences (NAS) advises the U.S. and Canadian governments on nutritional science for use in public policy and product labeling programs. Their 2002 Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids contains their findings and recommendations regarding consumption of trans fat.
Their recommendations are based on two key facts. First, "trans fatty acids are not essential and provide no known benefit to human health", whether of animal or plant origin. Second, given their documented effects on the LDL/HDL ratio, the NAS concluded "that dietary trans fatty acids are more deleterious with respect to coronary artery disease than saturated fatty acids". A 2006 review published in the New England Journal of Medicine (NEJM) that states "from a nutritional standpoint, the consumption of trans fatty acids results in considerable potential harm but no apparent benefit."
Because of these facts and concerns, the NAS has concluded there is no safe level of trans fat consumption. There is no adequate level, recommended daily amount or tolerable upper limit for trans fats. This is because any incremental increase in trans fat intake increases the risk of coronary artery disease.
Despite this concern, the NAS dietary recommendations have not included eliminating trans fat from the diet. This is because trans fat is naturally present in many animal foods in trace quantities, and thus its removal from ordinary diets might introduce undesirable side effects and nutritional imbalances. The NAS has, thus, "recommended that trans fatty acid consumption be as low as possible while consuming a nutritionally adequate diet". Like the NAS, the WHO has tried to balance public health goals with a practical level of trans fat consumption, recommending in 2003 that trans fats be limited to less than 1% of overall energy intake.
Health effects
While trans fatty acids (popularly called "trans fats") are edible, they have been implicated in many health problems.
Cardiovascular disease
The primary health risk identified for trans fat consumption is an elevated risk of coronary artery disease (CAD). A 1994 study estimated that over 30,000 cardiac deaths per year in the United States are attributable to the consumption of trans fats. By 2006 upper estimates of 100,000 deaths were suggested. A comprehensive review of studies of trans fats published in 2006 in the New England Journal of Medicine reports a strong and reliable connection between trans fat consumption and CAD, concluding that "On a per-calorie basis, trans fats appear to increase the risk of CAD more than any other macronutrient, conferring a substantially increased risk at low levels of consumption (1 to 3% of total energy intake)".
Major evidence for the effect of trans fat on CAD comes from the Nurses' Health Study – a cohort study that has been following 120,000 female nurses since its inception in 1976. In this study, Hu and colleagues analyzed data from 900 coronary events from the study's population during 14 years of followup. He determined that a nurse's CAD risk roughly doubled (relative risk of 1.93, CI: 1.43 to 2.61) for each 2% increase in trans fat calories consumed (instead of carbohydrate calories). By contrast, for each 5% increase in saturated fat calories (instead of carbohydrate calories) there was a 17% increase in risk (relative risk of 1.17, CI: 0.97 to 1.41). "The replacement of saturated fat or trans unsaturated fat by cis (unhydrogenated) unsaturated fats was associated with larger reductions in risk than an isocaloric replacement by carbohydrates." Hu also reports on the benefits of reducing trans fat consumption. Replacing 2% of food energy from trans fat with non-trans unsaturated fats more than halves the risk of CAD (53%). By comparison, replacing a larger 5% of food energy from saturated fat with non-trans unsaturated fats reduces the risk of CAD by 43%.
Another study considered deaths due to CAD, with consumption of trans fats being linked to an increase in mortality, and consumption of polyunsaturated fats being linked to a decrease in mortality.
Analytical data (blood work)
Consuming trans fats has been shown to increase the risk of coronary artery disease in part by raising levels of low-density lipoprotein (LDL, often termed "bad cholesterol"), lowering levels of high-density lipoprotein (HDL, often termed "good cholesterol"), increasing triglycerides in the bloodstream and promoting systemic inflammation.
Trans fat has been found to act like saturated in raising the blood level of LDL ("bad cholesterol"); but, unlike saturated fat, it also decreases levels of HDL ("good cholesterol"). The net increase in LDL/HDL ratio with trans fat, a widely accepted indicator of risk for coronary artery disease, is approximately double that due to saturated fat. One randomized crossover study published in 2003 comparing the effect of eating a meal on blood lipids of (relatively) cis and trans-fat-rich meals showed that cholesteryl ester transfer (CET) was 28% higher after the trans meal than after the cis meal and that lipoprotein concentrations were enriched in apolipoprotein(a) after the trans meals.
The citokyne test is a potentially more reliable indicator of CAD risk, although is still being studied. A study of over 700 nurses showed that those in the highest quartile of trans fat consumption had blood levels of C-reactive protein (CRP) that were 73% higher than those in the lowest quartile.
Intake of dietary trans fat perturbs the body's ability to metabolize essential fatty acids (EFAs, including omega-3) leading to changes in the phospholipid fatty acid composition of the arterial walls, thereby raising risk of coronary artery disease.
There are two accepted tests that measure an individual's risk for coronary artery disease, both blood tests. The first considers ratios of two types of cholesterol, the other the amount of a cell-signalling cytokine called C-reactive protein. The effect of trans fat consumption has been documented on each as follows:
Cholesterol ratio: This ratio compares the levels of LDL to HDL. Trans fat behaves like saturated fat by raising the level of LDL, but, unlike saturated fat, it has the additional effect of decreasing levels of HDL. The net increase in LDL/HDL ratio with trans fat is approximately double that due to saturated fat. (Higher ratios are worse.) One randomized crossover study published in 2003 comparing the effect of eating a meal on blood lipids of (relatively) cis and trans fat rich meals showed that cholesteryl ester transfer (CET) was 28% higher after the trans meal than after the cis meal and that lipoprotein concentrations were enriched in apolipoprotein(a) after the trans meals.
C-reactive protein (CRP): A study of over 700 nurses showed that those in the highest quartile of trans fat consumption had blood levels of CRP that were 73% higher than those in the lowest quartile.
Biochemical mechanisms
The mechanisms through which trans fatty acids contribute to coronary artery disease are fairly well understood. The mechanism for their effects on diabetes is still under investigation. They may impair the metabolism of long-chain polyunsaturated fatty acids (LCPUFAs). However, maternal pregnancy trans fatty acid intake has been inversely associated with LCPUFAs levels in infants at birth thought to underlie the positive association between breastfeeding and intelligence.
Trans fats are processed by the liver differently than other fats. They may cause liver dysfunction by interfering with delta 6 desaturase, an enzyme involved in converting essential fatty acids to arachidonic acid and prostaglandins, both of which are important to the functioning of cells.
Intake of dietary trans fat disrupts the body's ability to metabolize essential fatty acids (EFAs, including Omega-3) leading to changes in the phospholipid fatty acid composition of the arterial walls, thereby raising risk of coronary artery disease.
Consumption of industrial trans fat in the form of partially hydrogenated oil causes many health problems. They were abundant in fast food restaurants. They are consumed in greater quantities by people who lack access to a diet consisting of fewer partially-hydrogenated fats, or who often consume fast food. A diet high in trans fats can contribute to obesity, high blood pressure, and higher risk for heart disease. Trans fat is also implicated in Type 2 diabetes.
The major evidence for the effect of trans fat on CAD comes from the Nurses' Health Study – a cohort study that has been following 120,000 female nurses since its inception in 1976. In this study, Hu and colleagues analyzed data from 900 coronary events from the study's population during 14 years of followup. He determined that a nurse's CAD risk roughly doubled (relative risk of 1.93, CI: 1.43 to 2.61) for each 2% increase in trans fat calories consumed (instead of carbohydrate calories). By contrast, for each 5% increase in saturated fat calories (instead of carbohydrate calories) there was a 17% increase in risk (relative risk of 1.17, CI: 0.97 to 1.41). "The replacement of saturated fat or trans unsaturated fat by cis (unhydrogenated) unsaturated fats was associated with larger reductions in risk than an isocaloric replacement by carbohydrates." Hu also reports on the benefits of reducing trans fat consumption. Replacing 2% of food energy from trans fat with non-trans unsaturated fats more than halves the risk of CAD (53%). By comparison, replacing a larger 5% of food energy from saturated fat with non-trans unsaturated fats reduces the risk of CAD by 43%.
Another study considered deaths due to CAD, with consumption of trans fats being linked to an increase in mortality, and consumption of polyunsaturated fats being linked to a decrease in mortality.
Other health risks
Scientific studies have examined other negative effects of industrial trans fat beyond cardiovascular disease, with the next most studied area being type-2 diabetes.
Alzheimer's disease: A study published in Archives of Neurology in February 2003 suggested that the intake of both trans fats and saturated fats promote the development of Alzheimer disease, although not confirmed in an animal model. It has been found that trans fats impaired memory and learning in middle-age rats. The trans-fat eating rats' brains had fewer proteins critical to healthy neurological function and inflammation in and around the hippocampus, the part of the brain responsible for learning and memory. These are the exact types of changes normally seen at the onset of Alzheimer's, but seen after six weeks, even though the rats were still young. A systematic review of five articles based on four prospective cohort studies of individuals did not find a robust association between their intake of trans fatty acids and development of Alzheimer's disease (or several other forms of dementia). The review based this conclusion on finding that 4 of the 5 reports appeared biased and therefore recommended more well-designed prospective studies to clarify this issue.
Cancer: In 2007 the American Cancer Society stated that a relationship between trans fats and cancer "has not been determined." One study has found a positive connection between trans fat and prostate cancer. However, a larger study found a correlation between trans fats and a significant decrease in high-grade prostate cancer. An increased intake of trans fatty acids may raise the risk of breast cancer by 75%, suggest the results from the French part of the European Prospective Investigation into Cancer and Nutrition.
Diabetes: There is a growing concern that the risk of type 2 diabetes increases with trans fat consumption. However, consensus has not been reached. For example, one study found that risk is higher for those in the highest quartile of trans fat consumption. Another study has found no diabetes risk once other factors such as total fat intake and BMI were accounted for.
Obesity: Research indicates that trans fat may increase weight gain and abdominal fat, despite a similar caloric intake. A 6-year experiment revealed that monkeys fed a trans fat diet gained 7.2% of their body weight, as compared to 1.8% for monkeys on a mono-unsaturated fat diet. Although obesity is frequently linked to trans fat in the popular media, this is generally in the context of eating too many calories; there is not a strong scientific consensus connecting trans fat and obesity, although the 6-year experiment did find such a link, concluding that "under controlled feeding conditions, long-term TFA consumption was an independent factor in weight gain. TFAs enhanced intra-abdominal deposition of fat, even in the absence of caloric excess, and were associated with insulin resistance, with evidence that there is impaired post-insulin receptor binding signal transduction."
Liver dysfunction: Trans fats are metabolized differently by the liver than other fats and interfere with delta 6 desaturase. Delta 6 desaturase is an enzyme involved in converting essential fatty acids to arachidonic acid and prostaglandins, both of which are important to the functioning of cells.
Infertility in women: One 2007 study found, "Each 2% increase in the intake of energy from trans unsaturated fats, as opposed to that from carbohydrates, was associated with a 73% greater risk of ovulatory infertility...".
Major depressive disorder: Spanish researchers analysed the diets of 12,059 people over six years and found that those who ate the most trans fats had a 48 per cent higher risk of depression than those who did not eat trans fats. One mechanism may be trans-fats' substitution for docosahexaenoic acid (DHA) levels in the orbitofrontal cortex (OFC). Very high intake of trans-fatty acids (43% of total fat) in mice from 2 to 16 months of age was associated with lowered DHA levels in the brain (p=0.001). When the brains of 15 major depressive subjects who had committed suicide were examined post-mortem and compared against 27 age-matched controls, the suicidal brains were found to have 16% less (male average) to 32% less (female average) DHA in the OFC. The OFC controls reward, reward expectation, and empathy (all of which are reduced in depressive mood disorders) and regulates the limbic system.
Behavioral irritability and aggression: a 2012 observational analysis of subjects of an earlier study found a strong relation between dietary trans fat acids and self-reported behavioral aggression and irritability, suggesting but not establishing causality.
Diminished memory: In a 2015 article, researchers re-analyzing results from the 1999-2005 UCSD Statin Study argue that "greater dietary trans fatty acid consumption is linked to worse word memory in adults during years of high productivity."
Acne: According to a 2015 study, trans fats are one of several components of Western pattern diets which promote acne, along with carbohydrates with high glycemic load such as refined sugars or refined starches, milk and dairy products, and saturated fats, while omega-3 fatty acids, which reduce acne, are deficient in Western pattern diets.
Food industry response
Manufacturer response
Palm oil, a natural oil extracted from the fruit of oil palm trees that is semi-solid at room temperature (15–25 degrees Celsius), can potentially serve as a substitute for partially hydrogenated fats in baking and processed food applications, although there is disagreement about whether replacing partially hydrogenated fats with palm oil confers any health benefits. A 2006 study supported by the National Institutes of Health and the USDA Agricultural Research Service concluded that palm oil is not a safe substitute for partially hydrogenated fats (trans fats) in the food industry, because palm oil results in adverse changes in the blood concentrations of LDL and apolipoprotein B just as trans fat does.
In May 2003, BanTransFats.com Inc., a U.S. non-profit corporation, filed a lawsuit against the food manufacturer Kraft Foods in an attempt to force Kraft to remove trans fats from the Oreo cookie. The lawsuit was withdrawn when Kraft agreed to work on ways to find a substitute for the trans fat in the Oreo.
The J.M. Smucker Company, then the American manufacturer of Crisco (the original partially hydrogenated vegetable shortening), in 2004 released a new formulation made from solid saturated palm oil cut with soybean oil and sunflower oil. This blend yielded an equivalent shortening much like the prior partially hydrogenated Crisco, and was labelled zero grams of trans fat per 1 tablespoon serving (as compared with 1.5 grams per tablespoon of original Crisco). As of 24 January 2007, Smucker said that all Crisco shortening products in the US had been reformulated to contain less than one gram of trans fat per serving while keeping saturated fat content less than butter. The separately marketed trans fat free version introduced in 2004 was discontinued.
On 22 May 2004, Unilever, the corporate descendant of Joseph Crosfield & Sons (the original producer of Wilhelm Normann's hydrogenation hardened oils) announced that they had eliminated trans fats from all their margarine products in Canada, including their flagship Becel brand.
Agribusiness giant Bunge Limited, through their Bunge Oils division, are now producing and marketing an NT product line of non-hydrogenated oils, margarines and shortenings, made from corn, canola, and soy oils.
Since 2003, Loders Croklaan, a wholly owned subsidiary of Malaysia's IOI Group has been providing trans fat free bakery and confectionery fats, made from palm oil, for giant food companies in the U.S. to make margarine.
Major users' response
Beginning around 2000, as the scientific evidence and public concern about trans fat increased, major American users of trans fat began to switch to safer alternatives. The process received a large boost in 2003 when the FDA announced it would require trans fat labeling on packaged food starting in 2006. Packaged food companies then faced the choice of either eliminating trans fat from their products, or having to declare the trans fat on their nutrition label. Lawsuits in the U.S. against trans fat users also encouraged its removal.
Major American fast food chains including McDonald's, Burger King, KFC and Wendy's reduced and then removed partially hydrogenated oils (containing artificial trans fats) by 2009. This was a major step toward trans fat removal, as french fries were one of the largest sources of trans fat in the American diet, with a large serving of fries typically having about 6 grams of trans fat until around 2007.
Two other events were important in the removal of trans fat. First, in 2013 the FDA announced it planned to completely ban artificial trans fat in the form of partially hydrogenated oil. Second, soon after this, Walmart informed its suppliers they needed to remove trans fat by 2015 if they wanted to continue to sell their products at its stores. As Walmart is the largest brick-and-mortar retailer in the U.S., mainstream food brands had little choice but to comply.
These reformulations can be partly attributed to 2006 Center for Science in the Public Interest class action complaints, and to New York's restaurant trans fat ban, with companies such as McDonald's stating they would not be selling a unique product just for New York customers but would implement a nationwide or worldwide change.
See also
Diet and heart disease
Health crisis
Interesterified fat
Hydrogenated fat
Margarine
Notes
References
Further reading
External links
"Ban the Trans: These Sorry Lipids Should Go Away"
Center for Science in the Public Interest Trans Fat Page
Harvard School of Public Health webpage on trans-fat
Federal Register – 68 FR 41433 11 July 2003: Food Labeling: Trans Fatty Acids in Nutrition Labeling, Nutrient Content Claims, and Health Claims
Lipids
Nutrition
Carboxylic acids
Catalysis
Edible oil chemistry | Trans fat | [
"Chemistry"
] | 7,858 | [
"Catalysis",
"Biomolecules by chemical classification",
"Lipids",
"Carboxylic acids",
"Functional groups",
"Organic compounds",
"Chemical kinetics",
"Food chemistry",
"Edible oil chemistry"
] |
65,161,884 | https://en.wikipedia.org/wiki/Spermosphere |
Introduction
In plant science, the spermosphere is the zone surrounding a seed where soil, microorganisms, and seed germinating interact. The zone is a small area, typically 1–10 mm from the seed, but varying with seed type, the variety of soil microorganisms, the level of soil moisture, and other factors.
Importance
Within the spermosphere, a range of complex interactions take place among the germinating seed, the soil, and the microbiome. Because germination is a brief process, the spermosphere is transient, but the impact of the microbial activity within the spermosphere can have strong and long-lasting effects on the developing plant. The spermosphere can even have impacts on managing stress during germination, as seen with Bacillus strains and peanut plants.
Factors that influence spermosphere
Seeds exude various molecules that influence their surrounding microbial communities, either inhibiting or stimulating their growth. The composition of the exudates varies according to the plant type and such properties of the soil as its pH and moisture content. Soil type matters much more than seed type, specifically soil with a higher content of organic matter.
With these biochemical effects, the spermosphere develops both downward—to form the rhizosphere (upon the emergence of the plant's radicle)—and upward to form the laimosphere, which is the soil surrounding the growing plant stem, and the phyllosphere, which is the microbial community on the part of the plant above the soil. Specifically, the floral microbiota can play a role in the composition of the spermosphere like in plants such as wheat, grapevine, and rice. As the seed germinates, the function of the microbial community changes rather than its composition.
Protection of the seed
The spermosphere also acts as biological control for the germinating seed which means certain beneficial microorganisms can protect the seed from plant pathogens. Many plant pathogens such as Fusarium and Pythium ultimum can colonize a newly germinating seed within the first few hours of planting. The seed can exudate molecules and nutrients that attract beneficial microorganisms to their spermosphere which then prevent the colonization of pathogens. There has been specific research in this area with cottonseeds in which they were coated with a beneficial bacteria which prevented the seed from being infected with a Pythium ultimum infection.
References
Soil biology
Plant roots
Environmental soil science | Spermosphere | [
"Biology",
"Environmental_science"
] | 513 | [
"Environmental soil science",
"Soil biology"
] |
65,162,567 | https://en.wikipedia.org/wiki/Golden%20Gate%20of%20the%20Ecliptic | The Golden Gate of the Ecliptic is an asterism in the constellation Taurus that has been known for several thousand years. The asterism is formed of the two eye-catching open star clusters, the Pleiades and the Hyades that form the posts of a virtual gate on either side of the ecliptic line.
Since all planets as well as the Moon and the Sun always move very closely along the virtual circle of the ecliptic, all these seven orbiting bodies regularly pass through the Golden Gate of the Ecliptic. Since the Moon is the closest of these heavenly bodies to the Earth and it is inclined at a high enough angle to the ecliptic, on some occasions, the Moon can cover the stars of the open star clusters or even pass outside the Gate.
History
From 4000 to 1500 BC the equinox was within the constellation Taurus, and therefore great importance was attached to this constellation. The 4500 year old sky tablet of the neolithic Tal-Qadi Temple in Malta is thought to display the Golden Gate of the Ecliptic.
Sources
Michael A. Rappenglück: Palaeolithic Timekeepers Looking at the Golden Gate of the Ecliptic; The Lunar Cycle and the Pleiades in the Cave of La-Tête-du-lion (Ardèche, France) — 21,000 BP, in: Barbieri C., Rampazzi F. (editors): Earth-Moon Relationships, Springer, Dordrecht
External links
The Golden Gate of the Ecliptic. In Wikibook: The Tal-Qadi Sky Tablet
References
Asterisms (astronomy)
Taurus (constellation)
Pleiades
Hyades (star cluster) | Golden Gate of the Ecliptic | [
"Astronomy"
] | 351 | [
"Constellations",
"Taurus (constellation)",
"Sky regions",
"Asterisms (astronomy)"
] |
65,163,559 | https://en.wikipedia.org/wiki/Bleckley%20Plaza%20Plan | The Bleckley Plaza Plan was a proposed engineering project in Atlanta, Georgia, United States. Proposed by architect Haralson Bleckley in the early 1900s, the project would have seen numerous railroads in downtown Atlanta covered by a large public plaza that would have run from the Georgia State Capitol to Terminal Station, covering much of The Gulch. The project, while considered at numerous points in the early 1900s, never came to fruition.
History
The plan for a large plaza was created by Atlanta-based architect Haralson Bleckley in the early 1900s. The impetus behind the plan came in 1906 at a meeting of the Atlanta chapter of the American Institute of Architects (AIA) where the members declared the railroad tracks running between Forsyth Street and Central Avenue in downtown Atlanta were an eyesore that required fixing. The following year, Bleckley, an AIA member, reported back to the chapter with an extensive plan to cover the railroad tracks in downtown with a system of parks and high-rise buildings, raising the street level in the process. Railroads that would be covered as part of the plan included the Central of Georgia Railroad, the Georgia Railroad, and the Western and Atlantic Railroad. This plan, emblematic of the City Beautiful movement of the time, would have included the Georgia State Capitol on the eastern end of the plaza, new public buildings along the north and south sides of the plaza, and a newly constructed French Renaissance skyscraper at the western end that would have housed a city hall, railroad depot, and municipal offices. The plan was discussed in the local newspapers at the time, including The Atlanta Journal and The Atlanta Constitution in 1909.
The plan was reviewed and endorsed by the Atlanta chapter in 1910. That same year, the Atlanta Chamber of Commerce partnered with the Atlanta Real Estate Board to form a Planning Commission for the purposes of seeing Bleckley's plan come to fruition. Along with the Chamber of Commerce, the plan was endorsed by many prominent Atlanta citizens and by property owners who owned land near the railroad tracks. However, the project was opposed by the railroad owners, whose grants had placed the railroad tracks on street level, and by the government of Georgia, which owned the Western and Atlantic Railroad and felt that their air rights were valuable. For several years, the project remained stalled.
The project gained traction in 1916, when Atlanta mayor James G. Woodward created a Plaza Planning Commission to review the proposal. On May 3, the commission asked the Atlanta City Council to conduct an engineering study of the plan. On July 8, the architectural firm Barclay, Parsons, and Klapp presented their findings on the cost of the project and the creation of a new Union Station. The study was endorsed by the city council and the chamber of commerce, and was submitted to the Western and Atlantic Railroad Commission for their consideration. However, on June 27, 1917, the railroad commission recommended to the Georgia General Assembly that they not approve the plaza plan. Following this, the plaza plan was considered dead.
Future projects
Following the rejection of the plaza plan, Atlanta mayor Asa Griggs Candler created a commission to study the creation of viaducts in Atlanta. This led to the creation of numerous viaducts of Atlanta throughout the 1920s. The chamber of commerce would revive the idea for a public plaza covering the railroad gulch several times in the following decades, including in 1923, 1927, and 1930, though none of these plans lead to the creation of the plaza. Between 1928 and 1936, the city continued to expand its viaduct system, and in 1949, Plaza Park, a small public park, was opened near the proposed site of the plaza. Furthermore, a new Union Station was constructed in 1930 near the location Bleckley had proposed, though much smaller in scale. The idea for a plaza near the capitol building was later revived as Liberty Plaza, which was completed in 2016.
References
Bibliography
1900s architecture
Buildings and structures in Atlanta
History of Atlanta
Landscape architecture
Proposed buildings and structures in Georgia (U.S. state)
Proposed parks in the United States
Unbuilt buildings and structures in the United States
Urban planning in Georgia (U.S. state) | Bleckley Plaza Plan | [
"Engineering"
] | 838 | [
"Landscape architecture",
"Architecture"
] |
65,163,674 | https://en.wikipedia.org/wiki/PKNOX2 | PBX/Knotted 1 Homeobox 2 (PKNOX2) protein belongs to the three amino acid loop extension (TALE) class of homeodomain proteins, and is encoded by PKNOX2 gene in humans. The protein regulates the transcription of other genes and affects anatomical development.
Function
PKNOX2 protein regulates expression of other genes by binding to DNA in a sequence-specific manner, i.e. to specific DNA sequences. It binds to unique DNA recognition motifs, acting as a nuclear transcription factor. The nuclear transcription factor is a protein that regulates transcription of genetic information from DNA to messenger RNA. Other functions of PKNOX2 include actin filament binding. An important paralog of the PKNOX2 gene is PKNOX1.
Structure
PKNOX2 belongs to the three amino acid loop extension (TALE) class of homeodomain proteins. This class is characterized by a 3-amino acid extension between alpha helix 1 and 2 in the homeodomain.
Homeodomain proteins are sequence-specific transcription factors that share a highly conserved DNA binding domain and play a crucial role in cell proliferation, differentiation and death.
Clinical significance
In a 2014 review article of the genome-wide association findings of alcohol dependence, the researchers concluded that based on functional analysis (demonstration of a cause-effect relation), genetic variants related to the PKNOX2 gene may play a role in alcohol dependence risk, albeit a minor role comparing to the role played by the genes located in the alcohol dehydrogenase cluster.
See also
Homeobox
Binding to specific DNA sequences
References
Transcription factors | PKNOX2 | [
"Chemistry",
"Biology"
] | 338 | [
"Induced stem cells",
"Gene expression",
"Transcription factors",
"Signal transduction"
] |
65,165,192 | https://en.wikipedia.org/wiki/Wastewater-based%20epidemiology | Wastewater-based epidemiology (or wastewater-based surveillance or sewage chemical-information mining) analyzes wastewater to determine the consumption of, or exposure to, chemicals or pathogens in a population. This is achieved by measuring chemical or biomarkers in wastewater generated by the people contributing to a sewage treatment plant catchment. Wastewater-based epidemiology has been used to estimate illicit drug use in communities or populations, but can be used to measure the consumption of alcohol, caffeine, various pharmaceuticals and other compounds. Wastewater-based epidemiology has also been adapted to measure the load of pathogens such as SARS-CoV-2 in a community. It differs from traditional drug testing, urine or stool testing in that results are population-level rather than individual level. Wastewater-based epidemiology is an interdisciplinary endeavour that draws on input from specialists such as wastewater treatment plant operators, analytical chemists, molecular biologists and epidemiologists.
History
Wastewater-based epidemiology (WBE) can be applied in the field of research that uses the analysis of sewage and wastewater to monitor the presence, distribution, and prevalence of a disease or chemicals in communities. The technique has been used for several decades, and an example of its early application is in the 1940s when WBE was applied for the detection and distribution of poliovirus in the sewage of New York, Chicago, and other cities. Another early application came in 1954, in a study of schistosome of snails. Wastewater-based epidemiology thereafter spread to multiple countries. By the turn of the 21st century, numerous studies had adopted the technique. A 2005 study measured cocaine and its metabolite benzoylecgonine in water samples from the River Po in Italy.
Wastewater-based epidemiology is supported by government bodies such as the European Monitoring Centre for Drugs and Drug Addiction in Europe. Similar counterparts in other countries, such as the Australian Criminal Intelligence Commission in Australia and authorities in China use wastewater-based epidemiology to monitor drug use in their populations.
A group of Chinese scientists published the first WBE study on SARS-CoV-2 in 2020. They assessed whether the virus was present in fecal samples among 74 patients hospitalized for COVID-19 between January 16 and March 15, 2020, at a Chinese hospital. The first US SARS-CoV-2 study came from Boston. It reported a far higher rate of infection than had been estimated from individual PCR testing. It also served as a warning system, alerting the public to outbreaks (and outbreak ends) before positive test rates changed. However, considerable variability has been found within populations, based on symptom profiles, which may compromise measurement accuracy as the pathogen evolves.
As of 2022, WBE had reached 3,000 sites in 58 countries.
Technique
Wastewater-based epidemiology is analogous to urinalysis on a community scale. Small molecule compounds consumed by an individual can be excreted in the urine and/or feces in the form of the unchanged parent compound or a metabolite. In communities with sewerage, this urine combines with other wastes including other individuals' urine as they travel to a municipal wastewater treatment plant. The wastewater is sampled at the plant's inlet, prior to treatment. This is typically done with autosampler devices that collect 24-hour flow or temporally composite samples. These samples contain biomarkers from all the people contributing to a catchment. Collected samples are sent to a laboratory, where analytical chemistry techniques (such as liquid chromatography-mass spectrometry) are used to quantify compounds of interest. These results can be expressed in per capita loads based on the volume of wastewater. Per capita daily consumption of a chemical of interest (e.g. a drug) is determined as
where R is the concentration of a residue in a wastewater sample, F is the volume of wastewater that the sample represents, C is a correction factor which reflects the average mass and molar excretion fraction of a parent drug or a metabolite, and P is the number of people in a wastewater catchment. Variations or modifications may be made to C to account for other factors such as the degradation of a chemical during its transport in the sewer system.
For microbial surveillance, methods from molecular biology like PCR (qPCR and dPCR) and genetic sequencing are used. These methods are often highly susceptible to inhibition by various chemical substances commonly found in wastewater. Monitoring of inhibition or removal of these inhibitors is therefore recommended.
Applications
Commonly detected chemicals include, but are not limited to the following;
Cocaine
Amphetamine
Methamphetamine
Methylone
Ecstasy
Heroin
Alcohol
Nicotine
Caffeine
Ketamine
Opioids
Antidepressants
Antipsychotics
Antimicrobials
Antihistamines
Aritificial sweeteners
Temporal comparisons
By analyzing samples taken across different time points, day-to-day or longer-term trends can be assessed. This approach has illustrated trends such as increased consumption of alcohol and recreational drugs on weekends compared to weekdays. A temporal wastewater-based epidemiology study in Washington measured wastewater samples in Washington before, during and after cannabis legalisation. By comparing cannabis consumption in wastewater with sales of cannabis through legal outlets, the study showed that the opening of legal outlets led to a decrease in the market share of the illegal market.
Spatial comparisons
Differences in chemical consumption amongst different locations can be established when comparable methods are used to analyse wastewater samples from different locations. The European Monitoring Centre for Drugs and Drug Addiction conducts regular multi-city tests in Europe to estimate the consumption of illegal drugs. Data from these monitoring efforts are used alongside more traditional monitoring methods to understand geographical changes in drug consumption trends.
Microbial surveillance
Virus surveillance
Sewage can also be tested for signatures of viruses excreted via feces, such as the enteroviruses poliovirus, aichivirus and coronavirus. Systematic wastewater surveillance programs for monitoring enteroviruses, namely poliovirus, were instituted as early as 1996 in Russia. Wastewater testing is recognised as an important tool for poliovirus surveillance by the WHO, especially in situations where mainstream surveillance methods are lacking, or where viral circulation or introduction is suspected. Wastewater-based epidemiology of viruses has the potential to inform on the presence of viral outbreaks when or where it is not suspected. A 2013 study of archived wastewater samples from the Netherlands found viral RNA of Aichivirus A in Dutch sewage samples dating back to 1987, two years prior to the first identification of Aichivirus A in Japan.
During the COVID-19 pandemic, wastewater-based epidemiology using qPCR and/or RNA-Seq was used in various countries as a complementary method for assessing the load of COVID-19 and its variants in populations. Regular surveillance programs for monitoring SARS-Cov-2 in wastewater has been instituted in populations within countries such as Canada, UAE, China, Singapore, the Netherlands, Spain, Austria, Germany and the United States. In addition to surveillance of human wastewater, studies have also been conducted on livestock wastewater. A 2011 article reported findings of 11.8% of collected human wastewater samples and 8.6% of swine wastewater samples as positive of the pathogen Clostridioides difficile.
Applications against major outbreaks
Wastewater surveillance, which substantially expanded during the earlier COVID-19 pandemic was used to detect monkeypox in the 2022 monkeypox outbreak.
It is unclear how cost-effective wastewater surveillance is, but national coordination and standardized methods could be useful. Less common infections may be difficult to detect, including, such as those that cause hepatitis or foodborne illness. A warning of increased cases from wastewater surveillance can "provide health departments with critical lead time for making decisions about resource allocation and preventive measures" and "unlike testing of individual people, wastewater testing provides insights into the entire population within a catchment area".
A 2023 report by the National Academies of Sciences, Engineering and Medicine called for moving from the grass roots system that "sprung up in an ad hoc way, fueled by volunteerism and emergency pandemic-related funding" to a more standardized national system and suggested such a system "should be able to track a variety of potential threats, which could include future coronavirus variants, flu viruses, antibiotic resistant bacteria and entirely new pathogens".
Antimicrobial resistance
In 2022, genomic epidemiologists reported results from a global survey of antimicrobial resistance (AMR) via genomic wastewater-based epidemiology, finding large regional variations, providing maps, and suggesting resistance genes are also passed on between microbial species that are not closely related. A 2023 review on wastewater-based epidemiology opined the necessity of surveillance wastewater from farms with livestock, wet markets and surrounding areas given the greater risk of pathogen spillover to humans.
References
Epidemiology
Public health
Water management | Wastewater-based epidemiology | [
"Environmental_science"
] | 1,838 | [
"Epidemiology",
"Environmental social science"
] |
65,165,314 | https://en.wikipedia.org/wiki/Fat%20hydrogenation | Fat hydrogenation is the process of combining unsaturated fat with hydrogen in order to partially or completely convert it into saturated fat. Typically this hydrogenation is done with liquid vegetable oils resulting in solid or semi-solid fats.
Changing the degree of saturation of the fat changes some important physical properties, such as the melting range, which is why liquid oils become semi-solid. Solid or semi-solid fats are preferred for some baked goods such as biscuits and pie dough because how the fat mixes with flour produces a more desirable, crumbly texture in the baked product. Because partially hydrogenated vegetable oils are cheaper than animal fats, are available in a wide range of consistencies, and have other desirable characteristics such as increased oxidative stability and longer shelf life, they are the predominant fats used as shortening in most commercial baked goods.
The process is typically carried out at very high pressure, with the help of a nickel catalyst that is removed from the final product.
Process
Hydrogenating vegetable oil is done by raising a blend of vegetable oil and a metal catalyst, typically nickel, in near-vacuum to very high temperatures, and introducing hydrogen. This causes the carbon atoms of the oil to break double-bonds with other carbons. Each carbon atom becomes single-bonded to an individual hydrogen atom, and the double bond between carbons can no longer exist.
Full hydrogenation results in the conversion of all of the unsaturated fats into saturated fats by transforming all of the double bonds in the fat into single bonds. Partial hydrogenation reduces some, but not all, of the double bonds by the partial replacement with single bonds. The degree of hydrogenation is controlled by restricting the amount of hydrogen, reaction temperature and time, and the catalyst.
Issues
Cis–trans isomerization of some of the remaining unsaturated carbon bonds to their trans isomers during the partial hydrogenation process produces trans fat, which has been demonstrated to have cardiovascular health risk. The conversion from cis to trans bonds is chemically favored because the trans configuration has lower energy than the natural cis one. At equilibrium, the trans/cis isomer ratio is about 2:1.
Numerous studies have concluded that these trans fatty acids have negative health effects. As a result, many countries have enacted trans fat regulation that aims to eliminate or severely restrict their amount in industrialized food products, such as mandatory labeling of trans fats on food products. The United States Food and Drug Administration has concluded that partially hydrogenated oils are not generally recognized as safe, and since 2018 categorizes them as food additives, not food.
A number of old and new ingredients are available to replace partially-hydrogenated oil with significant levels of trans fat.
Improved hydrogenation processes can produce partially-hydrogenated oil with much lower amounts of trans fat.
Oils rich in monounsaturated fatty acids (especially oleic acid) obtained from plant breeding have higher stability compared to their polyunsaturated-rich ancestors, offering a similar improvement to shelf life.
Tropical oils (palm oil, palm kernel oil, coconut oil) are naturally rich in saturated fat. They can be further fractionated to increase the concentration of desired fatty acids.
Interesterification can be used to mix multiple types of fats, obtaining an oil with intermediate properties. For example, soybean oil and fully-hydrogenated soybean oil can be interesterified to obtain a semi-hard oil.
Dietary recommendations
Many health organizations recommend limiting or replacing dietary intake of trans fats and saturated fats, in favor of unsaturated fats.
History
Nobel Prize laureate Paul Sabatier worked in the late 1890s to develop the chemistry of hydrogenation. Whereas Sabatier considered hydrogenation of only vapors, the German chemist Wilhelm Normann showed in 1901 that liquid oils could be hydrogenated, and patented the process in 1902. Normann's hydrogenation process made it possible to stabilize affordable whale oil or fish oil for human consumption, a practice kept secret to avoid consumer distaste. During the years 1905–1910, Normann built a fat-hardening facility in the Herford company. At the same time, the invention was extended to a large-scale plant in Warrington, England, at Joseph Crosfield & Sons, Limited. It took only two years until the hardened fat could be successfully produced in the plant in Warrington, commencing production in late 1909. The initial year's production totalled nearly 3,000 tonnes. In 1909, Procter & Gamble acquired the United States rights to the Normann patent; in 1911, they began marketing the first hydrogenated shortening, Crisco (composed largely of partially hydrogenated cottonseed oil). Further success came from the marketing technique of giving away free cookbooks in which every recipe called for Crisco.
Before 1910, dietary fats in industrialized nations consisted mostly of butterfat, beef tallow, and lard. During Napoleon's reign in France in the early 19th century, a type of margarine was invented to feed troops using tallow and buttermilk. Soybeans began to be imported into the U.S. as a source of protein in the early 20th century, resulting in an abundance of soybean oil as a by-product that could be turned into a solid fat, thereby addressing a shortage of butterfat. With the advent of refrigeration, margarines based on hydrogenated fats presented the advantage that, unlike butter, they could be taken out of a refrigerator and immediately spread on bread. Some minor changes to the chemical composition of hydrogenated fats yielded superior baking properties compared to lard. As a result of these factors, margarine made from partially hydrogenated soybean oil began to replace butterfat. Partially hydrogenated fat such as Crisco and Spry, sold in England, began to replace butter and lard in baking bread, pies, cookies, and cakes in 1920.
Production of partially hydrogenated fats increased steadily in the 20th century as processed vegetable fats replaced animal fats in the U.S. and other Western countries. At first, the argument was a financial one due to the lower costs of margarines and shortenings compared to lard and butter, particularly for restaurants and manufacturers. However, during the 1980s regulators, physicians, nutritionists, popular health media, educational curricula and cookbooks began to promote diets low in saturated fats for health reasons. Advocacy groups in the U.S. responded by demanding the replacement of saturated animal and tropical fats with vegetable alternatives. The Center for Science in the Public Interest (CSPI) campaigned vigorously against the use of saturated fats by corporations, including fast-food restaurants, endorsing trans fats as a healthier alternative. The National Heart Savers Association took out full page ads in major newspapers, attacking the use of beef tallow in McDonald's French fries. They urged multinational fast-food restaurants and food manufacturers to switch to vegetable oils, and almost all targeted firms responded by replacing saturated fats with trans fats.
In the early 20th century, soybeans began to be imported into the United States as a source of protein; large quantities of soybean oil were a by-product. At the same time, there was not enough butterfat available for consumers. Margarine manufacturers found that hydrogenated fats worked better than the previously used combination of animal and liquid vegetable fats. Margarine made from hydrogenated soybean oil and vegetable shortenings such as Crisco and Spry, sold in England, began to replace butter and lard in baking bread, pies, cookies, and cakes by 1920.
Production of hydrogenated fats increased steadily until the 1960s, as processed vegetable fats replaced animal fats in the United States and other Western countries. At first, the argument was a financial one due to lower costs; advocates also said that the hydrogenated fats of margarine were healthier than the saturated fats of butter.
Since then the food industry has moved away from partially hydrogenated fats in response to the health concerns about trans fats, labeling requirements, and removal of trans fats from permitted food additives. They have been replaced with fully hydrogenated fats, vegetable oils that are naturally higher in saturated fat and therefore more solid at room temperature, such as palm oil and coconut oil, and interesterified fats, which cannot result in the formation of trans fats.
Alternatives to hydrogenation
The negative public image and strict regulations has not led to substantial interest in replacing partial hydrogenation. In principle, the level of trans fat may be altered by modification of the catalysts and conditions of hydrogenation.
See also
Hydrotreated vegetable oil
References
External links
Edible oil chemistry | Fat hydrogenation | [
"Chemistry"
] | 1,797 | [
"Edible oil chemistry",
"Food chemistry",
"Hydrogenation"
] |
65,166,559 | https://en.wikipedia.org/wiki/CrystalExplorer | CrystalExplorer (CE) is a freeware designed to analysis the crystal structure with *.cif file format.
CE is helpful to investigate different areas of solid-state chemistry such as Hirshfeld surface analysis, intermolecular interactions, polymorphism, effect of pressure and temperature on crystal structure, single-crystal to single-crystal reactions, analyzing the voids present in crystal, and structure-property relationships.
The graphical interface of CE towards the 3D crystal structure visualization aids in drawing the crystal structure with or without Hirshfeld surface.
History
CrystalExplorer launched as a graphical user interface which facilitates the visualization of interactions in molecular crystal structures. In 2006, M. A. Spackman's student Dylan Jayatilaka and coworkers presented a paper about their new crystallographic software in the occasion of 23rd European Crystallographic Meeting (ECM23) conducted in Leuven. This software was designed by School of Biomedical and Chemical Sciences, University of Western Australia, Nedlands 6009, Australia. From 2006 onward researchers started citing the program in their research papers.
CrystalExplorer 2.1 designed for Mac OS X, Windows and Linux platforms for the analysis of crystal structures and can be used to investigate many areas of solid-state chemistry such as studying intermolecular interactions, polymorphism, the effects of pressure and temperature on crystal structures, single-crystal to single-crystal reactions, analyzing crystal voids, structure-property relationships, isostructural compounds, and calculate intermolecular interaction energies.
Currently in 2020 September, there are more than 2000 research papers that cite CrystalExplorer software as per google scholar analysis.
Licence
CrystalExplorer17 is licensed free-of-charges under conditions, such as not using the free version of CrystalExplorer to conduct commercial or confidential research, or research that is not likely to be published in a peer-reviewed journal.
See also
Cambridge Crystallographic Data Centre
Crystallographic Information File
International Union of Crystallography
References
External links
Computational chemistry software
Crystallography software
Chemistry software for Linux | CrystalExplorer | [
"Chemistry",
"Materials_science"
] | 434 | [
"Computational chemistry software",
"Chemistry software",
"Crystallography",
"Computational chemistry",
"Chemistry software for Linux",
"Crystallography software"
] |
65,170,132 | https://en.wikipedia.org/wiki/John%20Price%20Jackson | John Price Jackson (27 September 1868, in Kennett Square – 2 April 1948) was an American electrical engineer and academic, civil servant and soldier.
John was born into a quaker family in Kennett Square, Pennsylvania. His parents were Josiah and Mary Price Jackson. His elder brother, Dugald C. Jackson, co-wrote some books with him and also had a career as an electrical engineer and academic.
When the Pennsylvania Department of Labor and Industry was founded by Governor John Kinley Tener, Jackson was appointed as the first Commissioner. He was subsequently confirmed in post by Governor Martin Grove Brumbaugh on 2 June 1917, but took a leave of absence from state office when he accepted a Commission in the US Army following the United States entry into the First World War.
Jackson served under Brigadier General Charles Gates Dawes in the office of the Chief Purchasing Agent for the American Expeditionary Forces (AEF). Dawes appointed him in February 1918 to head a labor bureau to coordinate hiring of civilian labor to support the AEF's logistical system in Europe.
Works
1896 Alternating Currents and Alternating Current Machinery (with Dugald C. Jackson) New York: Macmillan Co.
1902 An Elementary Book on Electricity and Magnetism (with Dugald C. Jackson) New York: Macmillan Co.
1915 "Some Industrial Lessons of the European War", The Annals of the American Academy of Political and Social Science Volume: 61 issue: 1, page(s): 45-50, September 1915
References
1868 births
1948 deaths
Electrical engineers | John Price Jackson | [
"Engineering"
] | 307 | [
"Electrical engineering",
"Electrical engineers"
] |
65,171,548 | https://en.wikipedia.org/wiki/Meshulam%27s%20game | In graph theory, Meshulam's game is a game used to explain a theorem of Roy Meshulam related to the homological connectivity of the independence complex of a graph, which is the smallest index k such that all reduced homological groups up to and including k are trivial. The formulation of this theorem as a game is due to Aharoni, Berger and Ziv.
Description
The game-board is a graph G. It is a zero-sum game for two players, CON and NON. CON wants to show that I(G), the independence complex of G, has a high connectivity; NON wants to prove the opposite.
At his turn, CON chooses an edge e from the remaining graph. NON then chooses one of two options:
Disconnection – remove the edge e from the graph.
Explosion – remove both endpoints of e, together with all their neighbors and the edges incident to them.
The score of CON is defined as follows:
If at some point the remaining graph has an isolated vertex, the score is infinity;
Otherwise, at some point the remaining graph contains no vertex; in that case the score is the number of explosions.
For every given graph G, the game value on G (i.e., the score of CON when both sides play optimally) is denoted by Ψ(G).
Game value and homological connectivity
Meshulam proved that, for every graph G:where is the homological connectivity of plus 2.
Examples
If G is the empty graph, then Ψ(G) = 0, since no explosions are needed.
If G has k connected components, then Ψ(G) ≥ k. Regardless of the order in which CON offers edges, each explosion made by NON destroys vertices in a single component, so NON needs at least k explosions to destroy all vertices.
If G is a union of k vertex-disjoint cliques, each of which contains at least two vertices, then Ψ(G) = k, since each explosion completely destroys a single clique.
If G has an independence domination number of at least k, , then . Proof: Let A be an independent set with domination number at least k. CON starts by offering all edges (a,b) where a is in A. If NON disconnects all such edges, then the vertices of A remain isolated so CON's score is infinity. If NON explodes such an edge, then the explosion removes from A only the vertices that are adjacent by b (the explosion at a does not destroy vertices of A, since A is an independent set). Therefore, the remaining vertices of A require at least k-1 vertices to dominate, so the domination number of A decreased by at most 1. Therefore, NON needs at least k explosions to destroy all vertices of A. This proves that .
Note: this also implies that , where is the line graph of G, and is the size of the largest matching in G. This is because the matchings in G are the independent sets in L(G). Each edge in G is a vertex in L(G), and it dominates at most two edges in the matching (= vertices in the independent set).
Similarly, when H is an r-partite hypergraph, .
If G is the complete bipartite graph Kn,n, and L(G) is its line graph, then . Proof: L(G) can be seen as an n-by-n array of cells, where each row is a vertex on one side, each column is a vertex on the other side, and each cell is an edge. In the graph L(G), each cell is a vertex, and each edge is a pair of two cells in the same column or the same row. CON starts by offering two cells in the same row; if NON explodes them, then CON offers two cells in the same column; if NON explodes them again, then the two explosions together destroy 3 rows and 3 columns. Therefore, at least explosions are required to remove all vertices.
Note: this result was generalized later: if F is any subgraph of Kn,n, then .
Proof for the case 1
To illustrate the connection between Meshulam's game and connectivity, we prove it in the special case in which , which is the smallest possible value of . We prove that, in this case, , i.e., NON can always destroy the entire graph using at most one explosion.
means that is not connected. This means that there are two subsets of vertices, X and Y, where no edge in connects any vertex of X to any vertex of Y. But is the independence complex of G; so in G, every vertex of X is connected to every vertex of Y. Regardless of how CON plays, he must at some step select an edge between a vertex of X and a vertex of Y. NON can explode this edge and destroy the entire graph.
In general, the proof works only one way, that is, there may be graphs for which .
See also
Hall-type theorems for hypergraphs
References
Combinatorial game theory
Homology theory
Graph theory | Meshulam's game | [
"Mathematics"
] | 1,046 | [
"Discrete mathematics",
"Recreational mathematics",
"Graph theory",
"Combinatorics",
"Game theory",
"Mathematical relations",
"Combinatorial game theory"
] |
65,171,762 | https://en.wikipedia.org/wiki/Lee%E2%80%93Yang%20theory | In statistical mechanics, Lee–Yang theory, sometimes also known as Yang–Lee theory, is a scientific theory which seeks to describe phase transitions in large physical systems in the thermodynamic limit based on the properties of small, finite-size systems. The theory revolves around the complex zeros of partition functions of finite-size systems and how these may reveal the existence of phase transitions in the thermodynamic limit.
Lee–Yang theory constitutes an indispensable part of the theories of phase transitions. Originally developed for the Ising model, the theory has been extended and applied to a wide range of models and phenomena, including protein folding, percolation, complex networks, and molecular zippers.
The theory is named after the Nobel laureates Tsung-Dao Lee and Yang Chen-Ning, who were awarded the 1957 Nobel Prize in Physics for their unrelated work on parity non-conservation in weak interaction.
Introduction
For an equilibrium system in the canonical ensemble, all statistical information about the system is encoded in the partition function,
where the sum runs over all possible microstates, and is the inverse temperature, is the Boltzmann constant and is the energy of a microstate. The moments of the energy statistics are obtained by differentiating the partition function with respect to the inverse temperature multiple times,
From the partition function, we may also obtain the free energy
Analogously to how the partition function generates the moments, the free energy generates the cumulants of the energy statistics
More generally, if the microstate energies depend on a control parameter and a fluctuating conjugate variable (whose value may depend on the microstate), the moments of may be obtained as
and the cumulants as
For instance, for a spin system, the control parameter may be an external magnetic field, , and the conjugate variable may be the total magnetization, .
Phase transitions and Lee–Yang theory
The partition function and the free energy are intimately linked to phase transitions, for which there is a sudden change in the properties of a physical system. Mathematically, a phase transition occurs when the partition function vanishes and the free energy is singular (non-analytic). For instance, if the first derivative of the free energy with respect to the control parameter is non-continuous, a jump may occur in the average value of the fluctuating conjugate variable, such as the magnetization, corresponding to a first-order phase transition.
Importantly, for a finite-size system, is a finite sum of exponential functions and is thus always positive for real values of . Consequently, is always well-behaved and analytic for finite system sizes. By contrast, in the thermodynamic limit, may exhibit a non-analytic behavior.
Using that is an entire function for finite system sizes, Lee–Yang theory takes advantage of the fact that the partition function can be fully characterized by its zeros in the complex plane of . These zeros are often known as Lee–Yang zeros or, in the case of inverse temperature as control parameter, Fisher zeros. The main idea of Lee–Yang theory is to mathematically study how the positions and the behavior of the zeros change as the system size grows. If the zeros move onto the real axis of the control parameter in the thermodynamic limit, it signals the presence of a phase transition at the corresponding real value of .
In this way, Lee–Yang theory establishes a connection between the properties (the zeros) of a partition function for a finite size system and phase transitions that may occur in the thermodynamic limit (where the system size goes to infinity).
Examples
Molecular zipper
The molecular zipper is a toy model which may be used to illustrate the Lee–Yang theory. It has the advantage that all quantities, including the zeros, can be computed analytically. The model is based on a double-stranded macromolecule with links that can be either open or closed. For a fully closed zipper, the energy is zero, while for each open link the energy is increased by an amount . A link can only be open if the preceding one is also open.
For a number of different ways that a link can be open, the partition function of a zipper with links reads
.
This partition function has the complex zeros
where we have introduced the critical inverse temperature , with . We see that in the limit , the zeros closest to the real axis approach the critical value . For , the critical temperature is infinite and no phase transition takes place for finite temperature. By contrast, for , a phase transition takes place at the finite temperature .
To confirm that the system displays a non-analytic behavior in the thermodynamic limit, we consider the free energy
or, equivalently, the dimensionless free energy per link
In the thermodynamic limit, one obtains
.
Indeed, a cusp develops at in the thermodynamic limit. In this case, the first derivative of the free energy is discontinuous, corresponding to a first-order phase transition.
Ising model
The Ising model is the original model that Lee and Yang studied when they developed their theory on partition function zeros. The Ising model consists of spin lattice with spins , each pointing either up, , or down, . Each spin may also interact with its closest spin neighbors with a strength . In addition, an external magnetic field may be applied (here we assume that it is uniform and thus independent of the spin indices). The Hamiltonian of the system for a certain spin configuration then reads
In this case, the partition function reads
The zeros of this partition function cannot be determined analytically, thus requiring numerical approaches.
Lee–Yang theorem
For the ferromagnetic Ising model, for which for all , Lee and Yang showed that all zeros of lie on the unit circle in the complex plane of the parameter . This statement is known as the Lee–Yang theorem, and has later been generalized to other models, such as the Heisenberg model.
Dynamical phase transitions
A similar approach can be used to study dynamical phase transitions. These transitions are characterized by the Loschmidt amplitude, which plays the analogue role of a partition function.
Connections to fluctuations
The Lee–Yang zeros may be connected to the cumulants of the conjugate variable of the control variable . For brevity, we set in the following. Using that the partition function is an entire function for a finite-size system, one may expand it in terms of its zeros as
where and are constants, and is the :th zero in the complex plane of . The corresponding free energy then reads
Differentiating this expression times with respect to , yields the :th order cumulant
Furthermore, using that the partition function is a real function, the Lee–Yang zeros have to come in complex conjugate pairs, allowing us to express the cumulants as
where the sum now runs only over each pair of zeros. This establishes a direct connection between cumulants and Lee–Yang zeros.
Moreover, if is large, the contribution from zeros lying far away from is strongly suppressed, and only the closest pair of zeros plays an important role. One may then write
This equation may be solved as a linear system of equations, allowing for the Lee–Yang zeros to be determined directly from higher-order cumulants of the conjugate variable:
Experiments
Being complex numbers of a physical variable, Lee–Yang zeros have traditionally been seen as a purely theoretical tool to describe phase transitions, with little or none connection to experiments. However, in a series of experiments in the 2010s, various kinds of Lee–Yang zeros have been determined from real measurements. In one experiment in 2015, the Lee–Yang zeros were extracted experimentally by measuring the quantum coherence of a spin coupled to an Ising-type spin bath. In another experiment in 2017, dynamical Lee–Yang zeros were extracted from Andreev tunneling processes between a normal-state island and two superconducting leads. Furthermore, in 2018, there was an experiment determining the dynamical Fisher zeros of the Loschmidt amplitude, which may be used to identify dynamical phase transitions.
See also
Lee–Yang theorem
References
Phase transitions | Lee–Yang theory | [
"Physics",
"Chemistry"
] | 1,697 | [
"Physical phenomena",
"Phase transitions",
"Phases of matter",
"Critical phenomena",
"Statistical mechanics",
"Matter"
] |
65,171,886 | https://en.wikipedia.org/wiki/Geopositioning | Geopositioning is the process of determining or estimating the geographic position of an object or a person.
Geopositioning yields a set of geographic coordinates (such as latitude and longitude) in a given map datum. Geographic positions may also be expressed indirectly, as a distance in linear referencing or as a bearing and range from a known landmark.
In turn, positions can determine a meaningful location, such as a street address.
Geoposition is sometimes referred to as geolocation, and the process of geopositioning may also be described as geo-localization.
Specific instances include:
animal geotracking, the process of inferring the location of animals over time;
positioning system, the mechanisms for the determination of geographic positions in general;
internet geolocation, geolocating a device connected to the internet;
and mobile phone tracking.
Geofencing
Geofencing involves creating a virtual geographic boundary (a geofence), enabling software to trigger a response when a device enters or leaves a particular area.
Geopositioning is a pre-requisite for geofencing.
Background
Geopositioning uses various visual and electronic methods including position lines and position circles, celestial navigation, radio navigation, radio and WiFi positioning systems, and the use of satellite navigation systems.
The calculation requires measurements or observations of distances or angles to reference points whose positions are known. In 2D surveys, observations of three reference points are enough to compute a position in a two-dimensional plane. In practice, observations are subject to errors resulting from various physical and atmospheric factors that influence the measurement of distances and angles.
A practical example of obtaining a position fix would be for a ship to take bearing measurements on three lighthouses positioned along the coast. These measurements could be made visually using a hand bearing compass, or in case of poor visibility, electronically using radar or radio direction finding. Since all physical observations are subject to errors, the resulting position fix is also subject to inaccuracy. Although in theory two lines of position (LOP) are enough to define a point, in practice 'crossing' more LOPs provides greater accuracy and confidence, especially if the lines cross at a good angle to each other. Three LOPs are considered the minimum for a practical navigational fix. The three LOPs when drawn on the chart will in general form a triangle, known as a 'cocked hat'. The navigator will have more confidence in a position fix that is formed by a small cocked hat with angles close to those of an equilateral triangle.
The area of doubt surrounding a position fix is called an error ellipse. To minimize the error, electronic navigation systems generally use more than three reference points to compute a position fix to increase the data redundancy. As more redundant reference points are added, the position fix becomes more accurate and the area of the resulting error ellipse decreases.
The process of using 3 reference points to calculate the location is called Trilateration, and when using more than 3 points, multilateration.
Combining multiple observations to compute a position fix is equivalent to solving a system of linear equations. Navigation systems use regression algorithms such as least squares in order to compute a position fix in 3D space. This is most commonly done by combining distance measurements to 4 or more GPS satellites, which orbit the Earth along known paths.
The result of position fixing is called a position fix (PF), or simply a fix, a position derived from measuring in relation to external reference points.
In nautical navigation, the term is generally used with manual or visual techniques, such as the use of intersecting visual or radio position lines, rather than the use of more automated and accurate electronic methods like GPS; in aviation, use of electronic navigation aids is more common. A visual fix can be made by using any sighting device with a bearing indicator. Two or more objects of known position are sighted, and the bearings recorded. Bearing lines are then plotted on a chart through the locations of the sighted items. The intersection of these lines is the current position of the vessel.
Usually, a fix is where two or more position lines intersect at any given time. If three position lines can be obtained, the resulting "cocked hat", where the three lines do not intersect at the same point, but create a triangle, gives the navigator an indication of the accuracy.
The most accurate fixes occur when the position lines are perpendicular to each other.
Fixes are a necessary aspect of navigation by dead reckoning, which relies on estimates of speed and course. The fix confirms the actual position during a journey. A fix can introduce inaccuracies if the reference point is not correctly identified or is inaccurately measured.
Indoor geopositioning
Geopositioning can be referred to both global positioning and outdoor positioning, using for example GPS, and to indoor positioning, for all the situations where satellite GPS is not a viable option and the localization process has to happen indoors. For indoor positioning, tracking and localization there are many technologies that can be used, depending on the specific needs and on the environmental characteristics.
See also
Attitude determination
Direction determination
Dynamic positioning
Geo-blocking
Geocoding
Geodetic positioning
GPS tracking unit
Geotagging
Geotargeting
Indoor positioning
Latitude determination
Longitude determination
Location-based service
Satellite navigation software
Triangulation
Vertical position measurement
W3C Geolocation API
References
Further reading
External links
Geodesy
Broad-concept articles | Geopositioning | [
"Mathematics"
] | 1,089 | [
"Applied mathematics",
"Geodesy"
] |
69,330,789 | https://en.wikipedia.org/wiki/COCONUTS-2b | COCONUTS-2 b is a gas giant exoplanet that orbits the M-type star L 34-26. With a mass of 8 Jupiters, it takes over one million years to complete one orbit around the star orbiting 7,506 AU away from it.
The planet was discovered in 2011 and was initially identified as a T9 free-floating brown dwarf WISEPA J075108.79−763449.6. During the COol Companions ON Ultrawide orbiTS (COCONUTS) survey, its association with L 34-26 was announced in 2021. At a distance of , COCONUTS-2b was the closest directly imaged exoplanet to Earth until Epsilon Indi Ab was imaged in 2024.
Proposed formation scenarios
The researchers found that it is unlikely that COCONUTS-2b was formed inside the protoplanetary disk of the host star and it is more likely that the planet formed on its own via high entropy formation (aka hot-start process).
The peculiar properties of COCONUTS-2b could be explained with different scenarios as proposed by Marocco et al. in 2024. The properties could be explained by a non-solar carbon-to-oxygen ratio, meaning that it formed inside a disk around L 34–26. In this scenario the most likely way COCONUTS-2b got in a higher orbit is by a stellar fly-by of two binaries or two planetary systems. In the second scenario L 34-26 is not actually young, but mimics youth due to tidal and/or magnetic interactions with an unseen companion. In this scenario COCONUTS-2b would be an old brown dwarf. In a third scenario COCONUTS-2b could be a captured old brown dwarf. This is however seen as unlikely due to the stellar fly-by requiring a low velocity.
Another study found that their preferred model showed a metallicity that is lower than the host star, which is inconsistent with in-situ binary-like formation. Only their third-preferred model is consistent with a binary-like formation, because in this model the metallicity of host star and planet agreed.
Atmosphere
The planet's spectral type suggests high amounts of methane, water vapor and low amounts of carbon monoxide in the atmosphere of COCONUTS-2b. It might also have both clouds and a non-equilibrium process in its atmosphere.
Due to its large orbital separation, COCONUTS-2b is a great laboratory to study the atmosphere and composition of young gas-giant exoplanets. Astronomers estimate the planet's temperature to be around .
Observations with Gemini/Flamingos-2 showed a spectral type of T, near the T/Y transition. The spectrum is also more consistent with disequilibrium chemistry and the presence of clouds. Additionally the atmosphere shows a diabatic thermal structure, meaning the pressure-temperature profile is non-adiabatic. Adiabatic means here an increase of the temperature with pressure. The observation also indicate a sub- or near-solar metallicity.
Host star
L 34–26, also known as COCONUTS-2A and TYC 9381–1809–1, is a M3-type dwarf star located 35 light-years away, in the constellation of Chamaeleon. The star is about one-third the mass of the Sun, with an age between 150 and 800 million years old.
Researchers using TESS found that L 34-26 showed stellar flares about every 0.48 days. It was the most active planet hosting star in their sample. The team studying the host star also found that L 34-26 is fast rotating with a rotation period of 2.83 days. The planet should not be influenced by the flares, because of the large orbital separation. The star is seen almost equator-on with i = 81.8±5.8 deg and might belong to the proposed Ursa Major corona, which is 400 million years old.
Gallery
References
External links
Exoplanets discovered in 2021
Exoplanets detected by direct imaging
Gas giants
Chamaeleon | COCONUTS-2b | [
"Astronomy"
] | 831 | [
"Chamaeleon",
"Constellations"
] |
69,333,714 | https://en.wikipedia.org/wiki/Lenovo%20ThinkPad%20X100e | The Lenovo ThinkPad X100e is a laptop from the ThinkPad line that was manufactured by Lenovo.
References
External links
Arch Linux Wiki - X100e
Thinkwiki.de - X100e
X100e
ThinkPad X100e
Computer-related introductions in 2010 | Lenovo ThinkPad X100e | [
"Technology"
] | 59 | [
"Mobile computer stubs",
"Mobile technology stubs"
] |
69,333,761 | https://en.wikipedia.org/wiki/Lenovo%20ThinkPad%20X300 | The Lenovo ThinkPad X300 is a discontinued laptop from the ThinkPad line that was manufactured by Lenovo.
Specifications
All ThinkPad X300s were shipped with Windows Vista Installed and were fitted with an Intel Core 2 Duo Processor. It had 3 USB ports.
Reception
It was generally well received. Notebookcheck noted that the X300 was the notebook that proved that Lenovo was a worthy successor to IBM. The X300 is the first ThinkPad without IBM branding.
References
External links
Thinkwiki.org - X300
McDonnell Technology Services - X300 Resources
ThinkPad X300
X300
Computer-related introductions in 2008 | Lenovo ThinkPad X300 | [
"Technology"
] | 134 | [
"Mobile computer stubs",
"Mobile technology stubs"
] |
69,335,787 | https://en.wikipedia.org/wiki/IBM%20ThinkPad%20T42 | The IBM ThinkPad T42 is a laptop from the ThinkPad line that was manufactured by IBM.
References
External links
Thinkwiki.de - T42
ThinkPad T42
T42
Computer-related introductions in 2004 | IBM ThinkPad T42 | [
"Technology"
] | 45 | [
"Mobile computer stubs",
"Mobile technology stubs"
] |
69,335,798 | https://en.wikipedia.org/wiki/IBM%20ThinkPad%20T40 | The IBM ThinkPad T40 is a laptop from the ThinkPad line that was manufactured by IBM.
References
External links
thinkwiki.de - T40
ThinkPad T40
T40
Computer-related introductions in 2003 | IBM ThinkPad T40 | [
"Technology"
] | 45 | [
"Mobile computer stubs",
"Mobile technology stubs"
] |
69,335,822 | https://en.wikipedia.org/wiki/IBM%20ThinkPad%20T41 | The IBM ThinkPad T41 is a laptop from the ThinkPad line that was manufactured by IBM.
References
External links
thinkwiki.de - T41
ThinkPad T41
T41
Computer-related introductions in 2004 | IBM ThinkPad T41 | [
"Technology"
] | 45 | [
"Mobile computer stubs",
"Mobile technology stubs"
] |
69,339,714 | https://en.wikipedia.org/wiki/Bioactive%20agents | Bioactive agents are substances that can influence an organism, tissue or cell. Examples include enzymes, drugs, vitamins, phytochemicals, and bioactive compounds.
Bioactive agents can be incorporated into polymers, which has applications in drug delivery and commercial production of household goods and biomedical devices. In drug delivery systems, bioactive agents are loaded into enzyme-responsive polymers which can then be cleaved by target enzymes. Activation of the bioactive agents leads to the release of therapeutic cargos.
References
Microbiology terms | Bioactive agents | [
"Biology"
] | 107 | [
"Microbiology terms"
] |
69,340,305 | https://en.wikipedia.org/wiki/Monochromatic%20radiation | In physics, monochromatic radiation is electromagnetic radiation with a single constant frequency or wavelength. When that frequency is part of the visible spectrum (or near it) the term monochromatic light is often used. Monochromatic light is perceived by the human eye as a spectral color.
When monochromatic radiation propagates through vacuum or a homogeneous transparent medium, it remains with a single constant frequency or wavelength; otherwise, it suffers refraction.
Practical monochromaticity
No radiation can be totally monochromatic, since that would require a wave of infinite duration as a consequence of the Fourier transform's localization property (cf. spectral coherence). In practice, "monochromatic" radiation — even from lasers or spectral lines — always consists of components with a range of frequencies of non-zero width.
Generation
Monochromatic radiation can be produced by a number of methods. Isaac Newton observed that a beam of light from the sun could be spread out by refraction into a fan of light with varying colors; and that if a beam of any particular color was isolated from that fan, it behaved as "pure" light that could not be decomposed further.
When atoms of a chemical element in gaseous state are subjected to an electric current, to suitable radiation, or to high enough temperature, they emit a light spectrum with a set of discrete spectral lines (monochromatic components), that are characteristic of the element. This phenomenon is the basis of the science of spectroscopy, and is exploited in fluorescent lamps and the so-called neon signs.
A laser is a device that generates monochromatic and coherent radiation through a process of stimulated emission.
Properties and uses
When monochromatic radiation is made to interfere with itself, the result can be visible and stable interference fringes that can be used to measure very small distances, or large distances with very high accuracy. The current definition of the metre is based on this technique.
In the technique of spectroscopic analysis, a material sample is exposed to monochromatic radiation, and the amount that is absorbed is measured. The graph of absorption as a function of the radiation's frequency is often characteristic of the material's composition. This technique can use radiation ranging from the microwaves, as in rotational spectroscopy, to gamma rays, as in Mössbauer spectroscopy.
See also
Wave
Acoustics
Optics
Monochromator
Interferometer
Diffraction grating
Dichroic filter
Monochromatic plane wave
Newton rings
References
Radiation | Monochromatic radiation | [
"Physics",
"Chemistry"
] | 505 | [
"Transport phenomena",
"Waves",
"Physical phenomena",
"Radiation"
] |
69,340,583 | https://en.wikipedia.org/wiki/Lane%20W.%20Martin | Lane Wyatt Martin is an American materials scientist and engineer specializing in complex oxide thin films, their physics and properties, and applications of the same. He is best known for his work on ferroelectric and multiferroic thin films. Currently he is a Robert A. Welch Professor of Materials Science and NanoEngineering, Chemistry, and Physics and Astronomy, and serves as the Director of the Rice Advanced Materials Institute (RAMI) at Rice University.
Early life and education
Martin was born in Lincoln, Nebraska and grew up primarily in Indiana, Pennsylvania and graduated from Indiana Area Senior High School. He earned his Bachelor of Science in Materials Science and Engineering from Carnegie Mellon University in December 2003 in just three-and-half years. He then pursued graduate studies at the University of California, Berkeley, obtaining a Master of Science (M.S., May 2006) and a Doctor of Philosophy (Ph.D., May 2008) in Materials Science and Engineering.
Career
Early Career
After completing his doctorate degree, Martin served as a Postdoctoral Fellow in the Quantum Materials Program at Lawrence Berkeley National Laboratory from 2008 to 2009. He began his academic career as an assistant professor in the Department of Materials Science and Engineering at the University of Illinois, Urbana-Champaign. As an assistant professor of materials science and engineering, Martin received a National Science Foundation CAREER Award for his proposal, "Enhanced Pyroelectric and Electrocaloric Effects in Complex Oxide Thin Film Heterostructures." He also helped devise a method to make thin films of ferroelectric material with twice the strain of traditional methods, giving the films exceptional electric properties. In 2013, Martin was nominated for a Presidential Early Career Award for Scientists and Engineers by the United States Department of Defense "for his research accomplishments in the synthesis and study of multifunctional materials that have enabled the development and understanding of fundamentally new materials phenomena and potential for advanced devices."
UC Berkeley
In 2014, Martin returned to the University of California, Berkeley as an associate professor, was promoted to professor in July 2018, and served as Vice/Associate Chair of the Department of Materials Science and Engineering from 2018 to 2021. From 2021 to 2023, Martin was a Chancellor’s Professor and Chair of the Department of Materials Science and Engineering at the University of California, Berkeley.
While serving in this role, he received the 2015 American Associate for Crystal Growth Young Author Award for his "outstanding accomplishments in the heteroepitaxial crystal growth of complex oxide thin films." He also received the 2016 Robert L. Coble Award for Young Scholars from the American Ceramic Society for outstanding contributions in ceramics research. In 2021, Martin was elected to the American Physical Society for his seminal contributions to the science of ferroelectrics. During his tenure as Chair, The University of California, Berkeley's Materials Science and Engineering (MSE) program was consistently ranked among the top in the nation. In the 2023 U.S. News & World Report rankings, the program was tied for the #2 position.
Rice University and the Rice Advanced Materials Institute (RAMI)
Martin joined Rice University in July 2023 as the Robert A. Welch Professor of Materials Science and NanoEngineering, Chemistry, and Physics and Astronomy and as inaugural Director of the Rice Advanced Materials Institute (RAMI), a leading hub for interdisciplinary research in advanced materials. RAMI brings together experts from materials science, chemistry, physics, and engineering to address pressing global challenges through innovations in material design and application. Under Martin's leadership, the institute focuses on exploring a diverse array of materials to enable transformative advances in areas such as next-generation, low-power electronics and communications, energy storage and conversion, and catalysis, separations, storage, and beyond while fostering collaboration across academic, industry, and governmental sectors. RAMI aims to advance the frontiers of science while promoting sustainable and impactful technological solutions, solidifying Rice University’s position as a global leader in materials research.
Research
Martin’s research focuses on the design and characterization of functional materials, particularly dielectric, piezoelectric, pyroelectric, ferroelectric, and multiferroic materials. His research focuses on the synthesis (growth), characterization, and utilization of emergent functions in such materials, particularly in epitaxial thin-film materials. By applying innovative approaches to making materials, he is able to access new states of matter and explores fundamental materials physics through growth and epitaxy, strain, defect, and interfacial engineering. In turn, his work explores the unique properties of these materials, including their ability to generate electric charge under mechanical stress and change physical dimensions when subjected to an electric field. Dr. Martin investigates the fundamental mechanisms governing the behavior of these materials at the atomic scale, aiming to enhance their performance for a wide range of applications. His research has significant implications for energy harvesting and conversion, advanced sensors, next-generation logic, and data-storage technologies, addressing global challenges in energy efficiency and the development of sustainable technologies.
Throughout his career, Martin has made significant contributions to understanding how to produce unexpected properties and phenomena in ferroelectrics materials. For example, his team used strain gradients induced by compositional gradients to induce built-in potentials that can give rise to properties not found in the bulk. Using similar approaches his team greatly expanded the range of functional temperatures for a given ferroelectric system by creating polarization gradients. In this work, the team directly measured the gradient and found that expanded the temperature range for optimal performance by the material across a 500-degree Celsius window (nearly an order of magnitude larger as compared to standard materials).
In other systems, Martin’s ability to finely control materials - at the unit cell level - has led to him and colleague discovering new states of matter in layered versions of materials. For example, by layering a ferroelectric and a dielectric repeatedly (with just each layer being a few nanometers thick), it was found that totally unexpected polarization textures could be formed including so-called polar vortices and polar skyrmions. These emergent features are topologically protected states that were not expected to form and it was only due to the team’s ability to control materials at these exacting sizes that such effects could be produced. In turn, these emergent structures exhibit a range of novel properties and respond in intriguing ways under excitation including being highly light sensitive and can undergo dramatic evolution of the phases under the same.
The materials Martin works on are being widely considered for an array of applications and devices. Among other contributions, he has helped developed pathways to reduce the energy costs for and speed up the switching of ferroelectric materials which could enable their more ready utilization in logic and memory applications. Likewise, Martin has developed ways to make such materials with properties rarely obtained in thin films - again showing a pathway to potential low-power logic and memory applications. Martin has also demonstrated how the same classes of materials could be useful for everything from waste-heat energy conversion via a process called pyroelectric energy conversion to solid-state capacitive energy storage good for pulsed energy needs, and even worked to develop new understanding of fuel cell materials. His work on relaxor ferroelectrics and antiferroelectrics are also bringing new understanding about how these materials look and respond to field. In the former, among other contributions, he and his colleagues developed new understanding of the nanoscale structure of these materials and how this relates to their properties and in the latter, he demonstrated that an electric-field-driven phase transition in these materials results in a large volume change that can be used actuation. Both of these classes of materials are being considered for applications in micro- and nano-electromechanical systems.
As of Jan. 2025, Martin has authored over 300 papers, with his work cited approximately 32,500 times, resulting in an h-index of 81.
Awards and honors
2004: William T. Lankford Jr. Memorial Scholarship, Carnegie Mellon University
2006: Gold Medal Award Winner, Materials Research Society Graduate Student Award
2006: Sapphire Award Winner, Graduate Excellence in Materials Science (GEMS), Materials Science and Technology Meeting
2004 - 2007: National Science Foundation IGERT Fellow in Nanoscience and Engineering
2007 - 2008: Intel Robert Noyce Fellow in Microelectronics
2008: Berkeley Summer Institute for Preparing Future Faculty - Institute Fellow
2010: Army Research Office Young Investigator Program (YIP) Award Winner
2012: National Science Foundation CAREER Award
2013: Dean’s Award for Excellence in Research, College of Engineering, University of Illinois
2015: American Association for Crystal Growth (AACG) Young Author Award
2016: Robert L. Coble Award for Young Scholars, American Ceramic Society
2017: Excellence in Laboratory Safety Grand Prize, UC Berkeley Environmental, Health, and Safety (EHS)
2018: Dow Lecturer, Department of Materials Science and Engineering, Northwestern University
2018 & 2019: Highly Cited Researcher – Ranked in the top 1% by citations for field and publication year in Web of Science
2019: IEEE-Ultrasonics, Ferroelectrics, and Frequency Control (UFFC) Society Ferroelectrics Young Investigator Award
2019: Zeiss ORION NanoFab Prize, Carl Zeiss SMT, Inc. (for innovative work on using ion beams to control material properties and the demonstration of the value of the NanoFab)
2021: Fellow, American Physical Society (APS, Awarded to no-more than one-half of one percent of Society membership) – For “seminal contributions to the science of ferroelectrics”
2022: Distinguished Lecturer, Department of Electrical and Computer Engineering, Texas A&M University
2022: Advanced Materials Hall of Fame, “Thin-film Ferroelectrics” (showcasing the outstanding achievements of leading international researchers in the field of materials science)
2022: Fellow, American Ceramics Society (ACerS, Awarded for outstanding contributions to the ceramic sciences and broad and productive scholarship in ceramic science and technology)
2022 - 2024: Defense Science Study Group (DSSG), Institute for Defense Analyses (IDA) and Defense Advanced Research Projects Agency (DARPA)
2024: Fellow, Materials Research Society (MRS, Awarded for seminal contributions to the science of ferroelectric and multiferroic thin film materials)
Personal life
Martin and his wife Sophi have one son together.
References
External links
Martin Research Group
People of Rice - Lane Martin
Living people
Scientists from Pennsylvania
Carnegie Mellon University alumni
University of California, Berkeley alumni
University of California, Berkeley faculty
University of Illinois Urbana-Champaign faculty
Fellows of the American Physical Society
Year of birth missing (living people)
Recipients of the Presidential Early Career Award for Scientists and Engineers
Materials science
Rice University
Rice University faculty
Rice University people
American materials scientists
Fellows of the American Ceramic Society
Fellows of the Materials Research Society | Lane W. Martin | [
"Physics",
"Materials_science",
"Engineering"
] | 2,220 | [
"Applied and interdisciplinary physics",
"Materials science",
"nan"
] |
69,341,579 | https://en.wikipedia.org/wiki/Plantae%20Delavayanae | Plantae Delavayanae: Plants from China collected in Yunnan by Father Delavay. is a book by Adrien René Franchet and Père Jean Marie Delavay, with Franchet describing and establishing the taxonomy for flora found by Delavay in Yunnan.
Background
Père Jean Marie Delavay was a missionary sent to China for Missions Etrangères de Paris (Foreign Missions of Paris) on an extended assignment in Yunnan. While in France in 1881, he met Père Armand David, a natural history collector and fellow missionary, and was persuaded to take up David's role of collecting plant specimens in China for the Paris Museum of Natural History. His meticulous methodology led to a prolific collection of plants, which included 200,000 specimens of 4,000 distinct species of flora. As Delavay did not have extensive training on botany, he would collect specimen with even the most minor of differences, which led to the discovery of 1,500 new species of plants within his collections. His work was only slowed when he contracted the bubonic plague in 1888, from which he only partially recovered.
Much of Delavay's collections that were sent to the Paris Museum of Natural History were processed by Adrien René Franchet. Franchet was a trained botanist focused on the authorship of taxonomy for the plant specimens arriving at the museum. Franchet primarily worked on the taxonomy of the collections from French missionaries in China and Japan, including Delavay, David, Paul Guillaume Farges, and Jean-André Soulié.
Franchet published much of his taxonomy work in academic journals, including
"Les Primula du Yun-nan" for Bulletin de la Société botanique de France in 1885.
Description
From 1889 to 1890, Franchet would publish Plantae Delavayanae. Plantes de Chine recueillies au Yun-nan par l'abbé Delavay. "Plantae Delavayanae: Plants from China collected in Yunnan by Father Delavay" is a book focused on the taxonomy of Père Jean Marie Delavay's flora collection. The text is written in Latin.
The book consists of 240 pages of text and 45 plates of illustrations. The original copy consisted of three fascicles, with pages 1-80 and plates 1-15 released in 1889; pages 81-160 and plates 16-30 later released in 1889; and pages 161-240 and plates 31-45 released in 1890. The book provided considerable credibility to Delavay's work in the field of botany. The International Plant Names Index acknowledges that 142 plant names were originally published in the "Pl. Delavay".
References
External links
Full Scan of the Original Book, including illustrations: https://www.biodiversitylibrary.org/item/41440#page/234/mode/1up
Florae (publication)
Botany
Flora of China | Plantae Delavayanae | [
"Biology"
] | 587 | [
"Flora",
"Florae (publication)",
"Plants",
"Botany"
] |
69,343,809 | https://en.wikipedia.org/wiki/Great%20North%20Bog | The Great North Bog is a large restoration initiative covering over 90% of the upland peatland in the North of England. It is a £200m project and aims to restore nearly 7,000 square kilometres of upland over 20 years. It is a partnership between the North Pennines Area of Outstanding Natural Beauty Partnership, Yorkshire Peat Partnership and the Moors for the Future Partnership. The area covers five national parks — the Peak District, Yorkshire Dales, North York Moors, Lake District and Northumberland.
Ecosystem recovery
Some of the peat is 8000 years old, and it is thought that about half the peatland needs restoring, by work in the winter. Much of these blanket bogs had been drained to graze sheep, this draining was subsidized in the 1950s and 1960s, and raise grouse for shooting. The land is currently managed by sheep farmers and landowners, and is thought to be losing peat depth at 2.5 cm a year while regrowing at 1 cm per year.
Flood control
Peat is now being washed away down deep channels and during storms the town of Otley is often flooded via the River Wharfe. Studies indicate that restoring part of the peatland with stone, wood or coir dams greatly slowed peak water flow.
Carbon capture
The peatlands currently store 400 million tonnes of carbon. The project say that damaged peat in the area releases 3.7 million tonnes of carbon annually, about 1% of UK greenhouse gas emissions. The programme includes a restoration and conservation plan which will make a significant contribution to the UK’s carbon sequestration targets.
References
Ecological restoration
Land management
Biosequestration
Peatlands
Bogs of England | Great North Bog | [
"Chemistry",
"Engineering"
] | 333 | [
"Ecological restoration",
"Environmental engineering"
] |
78,099,408 | https://en.wikipedia.org/wiki/Intelligence%20Technology%20Corporation | Intelligence Technology Corporation (ITC) was an American computer company that was a pioneer in mobile broadband technology. Based in Dallas, Texas, and active from 1986 to 2000, ITC was the first company to release a laptop with a built-in cellular modem, the ITC 286 CAT, in late 1988. The company developed several other laptops with built-in cellular modems until the early 1990s.
History
Intelligence Technology Corporation was founded in 1986 by Walker Morris and Charles Oliver Ekwurzel (1941–2019) in Dallas, Texas. Morris was a five-year veteran of the IBM PC clone industry before founding ITC; Ekwurzel was Morris's brother-in-law. ITC was originally a supplier for original equipment manufacturers of laptops before developing their own computer products. Development of the company's first product began in October 1987 when Morris, president of ITC, talked to Fred Neal Jr., an owner of a cellular phone license on the East Coast. Neal was hired as ITC's director, and together they developed three patents for the company's first product, the ITC 286 CAT, a laptop with a built-in cellular modem.
By April 1988, ITC had raised $750,000 in development funds, acquired through friends and investors in Marshall, Texas. In raising money the company, Morris intentionally eschewed venture capital, stating in May 1989: "We won't even talk to them. We're not about to give this company away to venture capitalists". By the middle of 1988, Morris contracted a Hong Kong manufacturer to produce the ITC 286 CAT (CAT short for Cellular AT), and by June 1988 the first four prototypes were shipped to various Fortune 500 companies for evaulation. The 286 CAT was originally slated to be marketed as the Form-Jet by Electronic Form Systems, a Carrollton-based systems integator that was a subsidiary of Computer Language Research (a mainframe software vendor), but ITC ultimately decided to market the computer by themselves.
The ITC 286 CAT was first unveiled to the public at the Las Vegas Convention Center during the 1988 COMDEX/Fall. A month later, the laptop was released to third-party American dealers. The ITC 286 CAT was the first laptop ever released with a built-in cellular modem (AMPS-compatible). It was capable of both data and voice transmissions and sold with an Oki-manufactured mobile handset; alternatively, users could have purchased an optional handset or use the laptop's built-in microphone to use the laptop as a speakerphone. By May 1989, ITC had sold nearly 700 units of the ITC 286 CAT, with $15 million in commitments for further sales of the computer at that point in time; Morris projected 6,000 total unit sales by the end of 1989. ITC aimed the 286 CAT at field workers, such as drilling crew and construction workers, needing to connect to their headquarters remotely, as well as traveling salesmen and insurers.
In November 1989 at the Las Vegas Convention Center, ITC unveiled five new cellular-capable laptops. The flagship among them were the 386 CEL AND 386 XCEL. The CEL family featured a redesigned chassis, with a slimmer profile as well as the addition of a slot on the lid of the laptop, acting as a cradle for the included Motorola-manufacturer handset. For the CELs, ITC upgraded the original Hayes-compatible cellular modem of the 286 CAT to one compatible with Microcom's MNP 5 (Microcom Networking Protocol Level 5) protocol. This allowed the laptops to connect to any such compatible modem, eliminating the need for special base stations at the receiving end of cellular calls. The processor was also upgraded from Intel's 16-bit 80286 of the 286 CAT to Intel's 32-bit 80386.
As well as the CEL family, ITC also introduced the 386 PEP, featuring an i386SX processor and a modem featuring the company's proprietary ITC-RM (Reliable Mode) error-correcting protocol that was a modification of Microcom's MNP Level 4 protocol making it function similar to (but not identically to) MNP Level 10. ITC decided to develop their own protocol to save on development costs. The 386 PEP was available with or without a cellular modem. On the low-end, ITC announced the 286 PAL, a non-cellular version of the 286 CAT. At the lowest-end, ITC announced the V20 PUP, featuring the same ITC-RM cellular modem of the ITC 386 PEP but with an 8-bit, 8088-compatible NEC V20 processor instead of an i386. This was the company's lowest cost offering, at US$1,200 (), several thousand dollars less than the ITC 386 PEP.
The CEL family was released in the United States in March 1990. ITC released the V20 PUP in 1991, which also served as their final laptop. The company continued selling laptops into at least November 1992. Their final products were a pair of external ARDIS cellular modems—one for personal computers, the Cinque Modem/Radio, and the other for laptops, the Pocket Modem/Radio. They were released in 1993. In 2000, ITC formally dissolved in the state of Texas.
Notes
References
External links
Intelligence Technology Corporation at FCCID.io
1986 establishments in Texas
2000 disestablishments in Texas
American companies established in 1986
American companies disestablished in 2000
Computer companies established in 1986
Computer companies disestablished in 2000
Defunct computer companies of the United States
Defunct computer hardware companies
Defunct computer systems companies
Mobile broadband
Laptops | Intelligence Technology Corporation | [
"Technology"
] | 1,187 | [
"Mobile telecommunications",
"Mobile broadband"
] |
78,099,765 | https://en.wikipedia.org/wiki/Juozas%20Matulis | Juozas Matulis (19 March 1899 – 25 June 1993) was a Lithuanian chemist, physicist and long-time president of the Lithuanian Academy of Sciences.
Biography
Education
In 1912, Matulis graduated from Juodpėnai Elementary School. He then studied at the Liepoja Gymnasium from 1920 he served in the electrical engineering battalion of the Lithuanian army. in 1923 Assistant Head of the Organization Department of the Post, Telegraph and Telephone Board.
In 1924, he graduated from the Adult Gymnasium of the Lithuanian Teachers' Trade Union in Kaunas and entered the Technical Faculty of the University of Lithuania. In 1925, he was transferred to the Physics and Chemistry Department of the Faculty of Mathematics and Natural Sciences. From 1925, Mautlis participated in the activities of the Lithuanian Social Democratic Party and was a member of its student organization Žiežirba.
In 1928, he was accepted to the University of Lithuania as a junior laboratory assistant and in 1929 he graduated from the university. From 1930 he was chief assistant of the Chemistry Department of Kaunas University. In 1931–1933, he completed an internship at the University of Leipzig and in 1934 he received a doctorate in chemistry.
Academic career
From 1936, he was associate professor and from 1940 the Dean of the Faculty of Mathematical Sciences and Natural Sciences of Vilnius University. Matulis career reached new heights after the Soviet occupation of Lithuania in 1940. In 1941, he was elected as an academician of the Academy of Sciences of the Lithuanian SSR and secretary of the Department of Natural Sciences. After the war, Matulis became the chairman of the restoration committee of the Lithuanian Academy of Sciences and in 1946, he was elected chairman of the Academy of Sciences, a position he held until 1984. He was also a Corresponding Member of the Academy of Sciences of the Soviet Union. Matulis was the founder of the national electrochemical school in Lithuania.
As politician he was a deputy of the Supreme Soviet of the Lithuanian SSR from 1947, and from 1959 to 1963 he was its deputy chairman. Matulis became a member of the Communist Party of Lithuania in 1950 and was a member of its Central Committee from 1956 to 1986.
References
1899 births
1993 deaths
Lithuanian chemists
Lithuanian physicists
Soviet chemists
Soviet physicists
Vytautas Magnus University alumni
Academic staff of Vilnius University
Leipzig University alumni
Corresponding Members of the USSR Academy of Sciences
Communist Party of Lithuania politicians
Communist Party of the Soviet Union members
Third convocation members of the Supreme Soviet of the Soviet Union
Fourth convocation members of the Supreme Soviet of the Soviet Union
Fifth convocation members of the Supreme Soviet of the Soviet Union
Sixth convocation members of the Supreme Soviet of the Soviet Union
Seventh convocation members of the Supreme Soviet of the Soviet Union
Eighth convocation members of the Supreme Soviet of the Soviet Union
Ninth convocation members of the Supreme Soviet of the Soviet Union
Tenth convocation members of the Supreme Soviet of the Soviet Union
Heroes of Socialist Labour
Recipients of the Order of Friendship of Peoples
Recipients of the Order of the Red Banner of Labour
Recipients of the Order of Lenin
Physical chemists | Juozas Matulis | [
"Chemistry"
] | 613 | [
"Physical chemists"
] |
78,101,583 | https://en.wikipedia.org/wiki/Nukatabe%20Kiln%20Site | The is an archaeological site with the ruins of a Kamakura period kiln, located in the Nukatabe Kitamachi neighborhood of the city of Yamatokōriyama, Nara Prefecture Japan. It was designated a National Historic Site of Japan in 1929.
Overview
roof tiles made of fired clay were introduced to Japan from Baekche during the 6th century along with Buddhism. During the 570s under the reign of Emperor Bidatsu, the king of Baekche sent six people to Japan skilled in various aspects of Buddhism, including a temple architect. Initially, tiled roofs were a sign of great wealth and prestige, and used for temple and government buildings. The material had the advantages of great strength and durability, and could also be made at locations around the country wherever clay was available.
The Nukatabe Tile Kiln ruins are located in series of low hills north of the confluence of the Saho River and Hatsuse River in the center of the Nara Basin. The site is 200 meters north of the temple Nukata-ji and was discovered during the excavation of an irrigation pond in 1928. Nukata-ji was founded by Prince Shotoku in the Asuka period and claims to be the predecessor of the great complex of Daian-ji in Heijō-kyō. The temple's influence declined during the Heian period, but it was rebuilt in the late Kamakura period by Eison and Ninsho of Saidai-ji. As excavated remains include flat tiles, round tiles, arabesque eaves tiles, and pottery fragments from the Kamakura period, and the kiln site is believed to be the remains of a tile kiln that was in operation during the reconstruction of that temple. The site consists of the ruins of three kilns. All are roughly the same size and are flat, standing side-by-side about 1.8 meters apart. Each kiln is about 2.3 meters long and 1.27 meters wide, with the firing chamber being about 1.3 meters long and 1 meter wide, and the floor is slightly sloping. The combustion chamber is located on the south side, one step lower than the floor of the firing chamber.
Currently, the westernmost kiln is covered and preserved. The shelter is locked, and visitors must contact the site in advance. It is about 1.2 kilometers east of Hirahata Station on the Kintetsu Railway Kashihara Line.
See also
List of Historic Sites of Japan (Nara)
References
External links
Yamatokoriyama City home page
Historic Sites of Japan
History of Nara Prefecture
Yamato Province
Kamakura period
Japanese pottery kiln sites
Yamatokōriyama | Nukatabe Kiln Site | [
"Chemistry",
"Engineering"
] | 547 | [
"Kilns",
"Japanese pottery kiln sites"
] |
78,102,743 | https://en.wikipedia.org/wiki/Surface%20Laptop%20Studio%202 | The Surface Laptop Studio 2 is a 2-in-1 convertible laptop developed by Microsoft. It was announced at a livestreamed event by the company alongside the Surface Laptop Go 3 on September 21, 2023. The device is a successor to the original Surface Laptop Studio released in 2021, and features an updated chip.
Features
Windows 11 operating system
Intel Raptor Lake 13th Gen i7-13700H
Nvidia GeForce RTX 4050/4060 (Consumer), or Nvidia RTX 2000 Ada (Enterprise) GPU
120 Hz refresh rate and Dolby Vision support
16GB/32GB/64GB LPDDR5X RAM
512GB/1TB/2TB NVME SSD storage
2 Thunderbolt 4 USB-C ports
Configurations
Hardware
The Surface Laptop Studio 2 has a very similar design to the original Surface Laptop Studio. It features the same three-position 14.4-inch touch display, 2400 x 1600 pixel resolution, 3:2 aspect ratio, removable SSD and Precision Haptic touchpad.
The key differences are:
The Laptop Studio 2 is thicker, at 0.86 inches (2.2 cm) compared to the original, which was 0.746 inches (1.9 cm) thick.
The new laptop is also heavier, weighing in at 4.37 pounds (2 kg) compared to the 4.00 pounds (1.8 kg) of the original Laptop Studio.
Finally, the new laptop is made of aluminum as opposed to magnesium.
Timeline
References
Studio 2
2-in-1 PCs
Computer-related introductions in 2023 | Surface Laptop Studio 2 | [
"Technology"
] | 329 | [
"Computing stubs",
"2-in-1 PCs",
"Computer hardware stubs",
"Crossover devices"
] |
78,102,874 | https://en.wikipedia.org/wiki/3C%20459 | 3C 459 known as IRAS 23140+0348, is a radio galaxy located in the constellation Pisces. It is located 2.74 billion light years from Earth and is classified as a Seyfert 2 and LINER galaxy.
Characteristics
3C 459 is categorized a Fanaroff-Riley class II radio galaxy. Its luminosity at both radio and far infrared wavelengths is Lv(4.8 GHz) = 1026.4 W Hz−1 and vLv(60 μm) = 1012.2 Lʘ. The host galaxy of 3C 459 is an elliptical galaxy with a disturbed outer morphology indicating a product of a galaxy merger. It also has a young stellar population.
3C 459 contains a triple radio structure, measuring a total extent of 29 kiloparsecs (kpc). It consists of a radio core and two radio lobes separated by 40 kpc. The radio core in 3C 459 has a compact steep radio spectrum with east and west extensions. As for the lobes on the other hand, the western lobe is equally 5.5 times further from the nucleus, while the eastern lobe is compact and more closer. It is also indicated to be significantly depolarized by interstellar medium since only the western lobe shows strong polarization.
According to follow-up observation by Chandra X-ray Observatory in 2014, 3C 459 shows X-ray emission properties. Although most X-ray emission originates from the radio core, a significant amount of it is found at larger angular separations from the core, surrounding the galaxy's lobes and radio jets.
There is also detections of diffused nuclear emissions and a filamentary ionized gas structure in 3C 459 creating a single-sided triangular-shaped region with an outward expansion of up to ~ 80 kpc. In its central emission line region, it is dominated by two compact knots of similar flux. Both of them are found to have an offset of ~ 400 km s-1 from velocity point of view suggesting a dual active galactic nuclei (AGN) system in 3C 459.
References
External links
3C 459 on SIMBAD
0459
Pisces (constellation)
070899
Radio galaxies
LINER galaxies
Seyfert galaxies
03.57
23140+0348 | 3C 459 | [
"Astronomy"
] | 474 | [
"Pisces (constellation)",
"Constellations"
] |
78,103,037 | https://en.wikipedia.org/wiki/Khambrangchak | Khambrangchak () is a bird species frequently mentioned in Meitei mythology, folklore of Ancient Kangleipak (early Manipur).
The folktale of Lady Khambrangchak shows a chain of damages caused by her while preparing for going to her family of orientation. Later, she was even forgiven by the judging king declaring it as a nature of women to be emotional during such preparation.
Khambrangchak is often known as "Khambrangchak Pidonnu" () or "Khambrangchak Tonsenu" ().
Identification
Some scholars identity Khambrangchak as yellow wagtail. Some scholars identify Khambrangchak as white pied wagtail.
Moirangthem Kirti Singh identified Khambrangchak as partridge.
A publication of the "World Wide Fund for Nature, India", identified Khambrangchak as multiple bird species. These species were (1) black naped blue fly catcher, (2) grey wagtail, (3) yellow headed wagtail, (4) white pied wagtail, etc.
Stories
Once there was a Khambrangchak couple. One day Lady Khambrangchak told her husband that she wished to visit her parental house. Her husband allowed her to go. Happily, Lady Khambrangchak went to a nearby river to bath to prepare to go.
There was a crab in the river. Lady Khambrangchak mistook the crab as a stone and stood on it. She started bathing, jumping and even singing happily. That disturbed the crab. The crab got angry and hurted her legs with its pincers (claws).
Lady Khambrangchak shouted in pain and flew away. She flew towards a fruit tree and sat on its branch.
There was a fruit about to fall down hanging in the branch. As Lady Khambrangchak sat on the branch, the fruit fell down to an anthill.
A group of angry ants came out from their house. They saw an old woman sitting nearby. They bit her.
The old woman rolled on the ground in pain. As she rolled, she destroyed a fence (wall). There was a bat's nest in the fence. It was also destroyed at the same time.
The bat got frightened and flew away. As bats could not see properly in daytime, that bat accidentally flew inside a King's elephant's nostril.
The bat couldn't find a way to go out. So, it stayed inside the elephant's nose.
From that day onwards, the elephant did not eat anything. It felt sick.
The King called a physician (medical doctor). The doctor observed the elephant.
He treated a medicine for the elephant. The smell of the medicine disturbed the bat. The bat flew out of the nose. King's guards caught the bat. The bat was brought before the King.
The King asked the bat why it stayed inside his elephant's nose. The bat blamed the old woman for everything. The old woman was brought before the King. She blamed the ants for everything. The ants were brought before the King. They blamed the fruit. The fruit was brought before the King. The fruit blamed Lady Khambrangchak for everything.
Lady Khambrangchak was brought before the King. She told him the truth. She confessed that she disturbed a crab.
The king said that it was not only women (human females) who were over excited to beautify themselves to visit their parental houses, but also the female birds and female animals getting over excited for the same reason.
The king set her free.
Thus, the preparation of Lady Khambrangchak for visiting her parental house became widely known and blameworthy in the entire kingdom.
In another version of the story, the group of ants bit a pig. The pig jumped on a banana tree. The banana tree could not hold the pig's weight. The tree fell on a fence. The fence was broken. It fell on a pond. The pond fell angry and complained to the king. The king called all of the accused. All of them told him whatever they had experienced. Later, the king set all of them free.
Interpretation
Regarding the preparation of Lady Khambrangchak for visiting her parental house (), scholar Chirom Rajketan Singh said,
In art
Khambrangchak is shown in an artwork of goddess Phouoibi (), along with flower designs, found in Senjam Chirang (). It is kept in the Manipur State Museum.
Related articles
Uchek Langmeitong
References
Other websites
Human–animal interaction
Animals in culture
Kings in Meitei mythology
Meitei folklore
Meitei mythology | Khambrangchak | [
"Biology"
] | 999 | [
"Human–animal interaction",
"Animals",
"Humans and other species"
] |
78,103,281 | https://en.wikipedia.org/wiki/SweetSpecter | SweetSpecter is a China-based group who engaged in a phishing attack against OpenAI employees, by sending emails with malware (SugarGh0st RAT) in attachments.
References
Malware
Security breaches
Hacker groups | SweetSpecter | [
"Technology"
] | 48 | [] |
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