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Biography
Heinz Haber
Heinz Haber (May 15, 1913 in Mannheim – February 13, 1990 in Hamburg) was a Germany physicist and science writer who primarily became known for his TV programs and books about physics and environmental subjects. His lucid style of explaining hard science has frequently been imitated by later popular science presenters in Germany. Heinz Haber was born in 1913. His father, Carl Haber, was dir
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  • 15 Dec 2022
Topic Review
Enterococcus
Enterococci derived from an ancestor that was a commensal of aquatic life forms, when animals first became terrestrial. To cope with the stresses of the new terrestrial habitat, enterococci evolved to be tough bugs, resistant to a wide range of environmental and host factors. That made them extremely successful not only in adapting to the new way of life of their hosts, but also in colonizing other non-animal, and even inanimate, environments - such as feeds and foods. The plasticity of the enterococcal genome, together with their notable ability to trade virulence and antibiotic resistance, have enabled them to also become notable opportunistic, multi-resistant pathogens and act as reservoirs of pathogenicity and resistance determinants.
  • 2.5K
  • 31 Aug 2020
Biography
Gerard K. O'Neill
Gerard Kitchen O'Neill (February 6, 1927 – April 27, 1992) was an American physicist and space activist. As a faculty member of Princeton University, he invented a device called the particle storage ring for high-energy physics experiments.[1] Later, he invented a magnetic launcher called the mass driver.[2] In the 1970s, he developed a plan to build human settlements in outer space, including
  • 2.5K
  • 30 Nov 2022
Topic Review
Cyanopsitta
Spix's macaw (Cyanopsitta spixii), also known as the little blue macaw, is a macaw native to Brazil. It is a member of tribe Arini in the subfamily Arinae (Neotropical parrots), part of the family Psittacidae (the true parrots). It was first described by German naturalist Georg Marcgrave, when he was working in the State of Pernambuco, Brazil in 1638 and it is named for German naturalist Johann Baptist von Spix, who collected a specimen in 1819 on the bank of the Rio São Francisco in northeast Bahia in Brazil. The bird is a medium-size parrot weighing about 300 grams (11 oz), smaller than most of the large macaws. Its plumage is various shades of blue, with a grey-blue head, light blue underparts, and vivid blue upperparts. Males and females are almost identical in appearance, however the females are slightly smaller on average. Currently there are no known survivors of the species outside of captivity. The species inhabited riparian Caraibeira (Tabebuia aurea) woodland galleries in the drainage basin of the Rio São Francisco within the Caatinga dry forest climate of interior northeastern Brazil. It had a very restricted natural habitat due to its dependence on the tree for nesting, feeding and roosting. It feeds primarily on seeds and nuts of Caraiba and various Euphorbiaceae (spurge) shrubs, the dominant vegetation of the Caatinga. Due to deforestation in its limited range and specialized habitat, the bird has been rare in the wild throughout the twentieth century. It has always been very rare in captivity, partly due to the remoteness of its natural range. The IUCN regard the Spix's macaw as extinct in the wild. Its last known stronghold in the wild was in northeastern Bahia, Brazil and sightings are very rare. After a 2000 sighting of a male bird, the next and last sighting was in 2016. The species is now maintained through a captive breeding program at several conservation organizations under the aegis of the Brazilian government. It is listed on CITES Appendix I, which makes trade illegal except for legitimate conservation, scientific or educational purposes. The Brazilian Chico Mendes Institute for Biodiversity Conservation (ICMBio) is conducting a project Ararinha-Azul with an associated plan to restore the species to the wild as soon as sufficient breeding birds and restored habitat are available.
  • 2.5K
  • 20 Oct 2022
Biography
Piara Singh Gill
Piara Singh Gill (28 October 1911 – 23 March 2002) was an India n nuclear physicist who was a pioneer in cosmic ray nuclear physics and worked on the American Manhattan project.[1] He was the first Director of Central Scientific Instruments Organisation (CSIO) of India .[2] He was research fellow of University of Chicago (1940).[3] He was research Professorship fellow of Tata Institute of Fu
  • 2.5K
  • 17 Nov 2022
Biography
William Gilbert
William Gilbert (24 May 1544 – 30 November 1603), also known as Gilberd, was an English physician, physicist and natural philosopher. He passionately rejected both the prevailing Aristotelian philosophy and the Scholastic method of university teaching. He is remembered today largely for his book De Magnete (1600), and is credited as one of the originators of the term "electricity". He is regar
  • 2.5K
  • 01 Dec 2022
Biography
Max Abraham
Max Abraham (German: [ˈaːbʀaham]; 26 March 1875 – 16 November 1922) was a Germany physicist known for his work on electromagnetism and his opposition to the theory of relativity. Abraham was born in Danzig, Imperial Germany (now Gdańsk in Poland ) to a family of Jewish merchants. His father was Moritz Abraham and his mother was Selma Moritzsohn. Attending the University of Berlin, he st
  • 2.5K
  • 25 Nov 2022
Topic Review
Emmer
Emmer wheat or hulled wheat is a type of awned wheat. Emmer is a tetraploid (2n = 4x = 28 chromosomes). The domesticated types are Triticum turgidum subsp. dicoccum and Triticum turgidum conv. durum. The wild plant is called Triticum turgidum subsp. dicoccoides. The principal difference between the wild and the domestic is that the ripened seed head of the wild plant shatters and scatters the seed onto the ground, while in the domesticated emmer the seed head remains intact, thus making it easier for humans to harvest the grain. Along with einkorn wheat, emmer was one of the first crops domesticated in the Near East. It was widely cultivated in the ancient world, but is now a relict crop in mountainous regions of Europe and Asia. Emmer is considered a type of farro food especially in Italy.
  • 2.5K
  • 01 Dec 2022
Biography
Michael James Whale
Michael James Whale (born 13 May 1951), known professionally as James Whale, is an English radio personality, television presenter, podcast host and author. He gained initial prominence in the 1980s as the host of The James Whale Radio Show on Radio Aire in Leeds, which was simulcast on national television. From 1995 to 2008, Whale hosted a night time radio show on talkSPORT, followed by stints
  • 2.5K
  • 15 Dec 2022
Topic Review
Genetic Use Restriction Technology
Genetic use restriction technology (GURT), also known as terminator technology or suicide seeds, is the name given to proposed methods for restricting the use of genetically modified crops by activating (or deactivating) some genes only in response to certain stimuli, especially to cause second generation seeds to be infertile. The development and application of GURTs is primarily an attempt by private sector agricultural breeders to increase the extent of protection on their innovations. The technology was originally developed under a cooperative research and development agreement between the Agricultural Research Service of the United States Department of Agriculture and Delta and Pine Land company in the 1990s and is not yet commercially available. GURT was first reported on by the Subsidiary Body on Scientific, Technical and Technological Advice (SBSTTA) to the UN Convention on Biological Diversity and discussed during the 8th Conference of the Parties to the United Nations Convention on Biological Diversity in Curitiba, Brazil, March 20–31, 2006.
  • 2.5K
  • 29 Nov 2022
Topic Review
Selfish Brain Theory
The “Selfish Brain” theory describes the characteristic of the human brain to cover its own, comparably high energy requirements with the utmost of priorities when regulating energy fluxes in the organism. The brain behaves selfishly in this respect. The "Selfish brain" theory amongst other things provides a possible explanation for the origin of obesity, the severe and pathological form of overweight. The Luebeck obesity and diabetes specialist Achim Peters developed the fundamentals of this theory between 1998 and 2004. The interdisciplinary “Selfish Brain: brain glucose and metabolic syndrome” research group headed by Peters and supported by the German Research Foundation (DFG) at the University of Luebeck has in the meantime been able to reinforce the basics of the theory through experimental research.
  • 2.5K
  • 04 Nov 2022
Biography
Ronald McNair
Ronald Erwin McNair (October 21, 1950 – January 28, 1986) was an American physicist and NASA astronaut. He died during the launch of the Space Shuttle Challenger on mission STS-51-L, in which he was serving as one of three mission specialists. He is survived by his wife, Cheryl, and two children. His kids were Jay Charey Mcnair (Daughter) and Reginald Ervin Mcnair (son) Born October 21, 195
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  • 03 Jan 2023
Topic Review
TLR4
Toll-like receptor 4 is a protein that in humans is encoded by the TLR4 gene. TLR4 is a transmembrane protein, member of the toll-like receptor family, which belongs to the pattern recognition receptor (PRR) family. Its activation leads to an intracellular signaling pathway NF-κB and inflammatory cytokine production which is responsible for activating the innate immune system. TRL4 expressing cells are myeloid (erythrocytes, granulocytes, macrophages) rather than lymphoid (T-cells, B-cells, NK cells). Most myeloid cells also express high levels of CD14, which facilitates activation of TLR4 by LPS. It is most well known for recognizing lipopolysaccharide (LPS), a component present in many Gram-negative bacteria (e.g. Neisseria spp.) and selected Gram-positive bacteria. Its ligands also include several viral proteins, polysaccharide, and a variety of endogenous proteins such as low-density lipoprotein, beta-defensins, and heat shock protein. Palmitic acid is also a TLR4 agonist. TLR4 has also been designated as CD284 (cluster of differentiation 284). The molecular weight of TLR4 is approximately 95 kDa.
  • 2.5K
  • 29 Nov 2022
Biography
Robert Wald
Robert M. Wald (/wɔːld/; born June 29, 1947 in New York City ) is an American theoretical physicist who studies gravitation. His research interests include general relativity, black holes, and quantum gravity. He is also a science communicator and textbook author. He is the son of the mathematician and statistician Abraham Wald. Wald's parents died in a plane crash when he was three years o
  • 2.5K
  • 21 Nov 2022
Topic Review
Ketosis
Ketosis is a metabolic state characterized by elevated levels of ketone bodies in the blood or urine. Physiological ketosis is a normal response to low glucose availability, such as low-carbohydrate diets or fasting, that provides an additional energy source for the brain in the form of ketones. In physiological ketosis, ketones in the blood are elevated above baseline levels, but the body's acid–base homeostasis is maintained. This contrasts with ketoacidosis, an uncontrolled production of ketones that occurs in pathologic states and causes a metabolic acidosis, which is a medical emergency. Ketoacidosis is most commonly the result of complete insulin deficiency in type 1 diabetes or late-stage type 2 diabetes. Ketone levels can be measured in blood, urine or breath and are generally between 0.5 and 3.0 millimolar (mM) in physiological ketosis, while ketoacidosis may cause blood concentrations greater than 10 mM. Trace levels of ketones are always present in the blood and increase when blood glucose reserves are low and the liver shifts from primarily metabolizing carbohydrates to metabolizing fatty acids. This occurs during states of increased fatty acid oxidation such as fasting, starvation, carbohydrate restriction, or prolonged exercise. When the liver rapidly metabolizes fatty acids into acetyl-CoA, some acetyl-CoA molecules can then be converted into ketone bodies: acetoacetate, beta-hydroxybutyrate, and acetone. These ketone bodies can function as an energy source as well as signalling molecules. The liver itself cannot utilize these molecules for energy, so the ketone bodies are released into the blood for use by peripheral tissues including the brain. When ketosis is induced by carbohydrate restriction, it is sometimes referred to as nutritional ketosis. A low-carbohydrate, moderate protein diet that can lead to ketosis is called a ketogenic diet. Ketosis is well-established as a treatment for epilepsy and is also effective in treating type 2 diabetes.
  • 2.5K
  • 25 Oct 2022
Biography
Luiz Philippe de Orléans E Bragança
Luiz Philippe of Orléans-Braganza (Portuguese: Luiz Philippe de Orléans e Bragança; born 3 April 1969) is a Brazilian political scientist, activist, entrepreneur, and member of the House of Orléans-Braganza. He was elected Federal Deputy for São Paulo in the 2018 Brazilian elections for the Social Liberal Party with 118,457 votes.[1] Luiz Philippe was born in Rio de Janeiro in 1969, the
  • 2.5K
  • 26 Dec 2022
Biography
Harvey Fletcher
Harvey Fletcher (September 11, 1884 – July 23, 1981) was an American physicist.[1] Known as the "father of stereophonic sound," he is credited with the invention of the 2-A audiometer[2] and an early electronic hearing aid.[3][4] He was an investigator into the nature of speech and hearing, and made contributions in acoustics, electrical engineering, speech, medicine, music, atomic physics, so
  • 2.4K
  • 25 Nov 2022
Topic Review
Social Sequence Analysis
Social sequence analysis is a special application of sequence analysis, a set of methods that were originally designed in bioinformatics to analyze DNA, RNA, and peptide sequences. Social sequence analysis involves the examination of ordered social processes, ranging from microsocial interaction patterns (for example, turn-taking dynamics in conversations) and interpersonal contact dynamics to the development of social hierarchies and macrosocial temporal patterns. The analysis of such patterns can involve descriptive accounts of sequence patterns, statistical event history analysis, optimal matching analysis, narrative or event structure analysis, and dynamic social network sequencing. After being introduced to the social sciences in the 1980s and a period of slow growth during the 1990s, social sequence methods have become increasingly prevalent.
  • 2.4K
  • 01 Nov 2022
Biography
Ajahn Brahm
Phra Visuddhisamvarathera AM, known as Ajahn Brahmavaṃso, or simply Ajahn Brahm (born Peter Betts[1] on 7 August 1951), is a British-Australian Theravada Buddhist monk. Currently Ajahn Brahm is the Abbot of Bodhinyana Monastery, in Serpentine, Western Australia, Spiritual Adviser to the Buddhist Society of Victoria, Spiritual Adviser to the Buddhist Society of South Australia, Spiritual Patron
  • 2.4K
  • 14 Nov 2022
Biography
Kris Kobach
Kris William Kobach (['koʊbɑk]; born March 26, 1966) is an American politician serving as the 31st and current Secretary of State of Kansas since 2011.[1] A former Chairman of the Kansas Republican Party and member of the City Council of Overland Park, Kansas, he was the Republican nominee in Kansas's 3rd congressional district in the 2004 election, losing to the Democratic incumbent, Dennis M
  • 2.4K
  • 09 Dec 2022
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