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Topic Review

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

Marco Visconti (born 4 June 1978) is an Italian occultist and musician.[1] He is known for his work with the musical group XP8[2] and Faderhead.[3] Under the name Azrael[4] Visconti is an past officer[5] of the Thelemic organisation Ordo Templi Orientis (O.T.O.) in London,[6] and scholar of the occult works of English author Aleister Crowley, the founder of the philosophy and religion of Thelema

2.4K
22 Nov 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.

2.4K
29 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

2.4K
01 Dec 2022

Biography

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

2.4K
03 Jan 2023

Biography

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

2.4K
21 Nov 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

2.4K
26 Dec 2022

Biography

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

2.4K
15 Dec 2022

Topic Review

Sparrows are a family of small passerine birds. They are also known as true sparrows, or Old World sparrows, names also used for a particular genus of the family, Passer. They are distinct from both the American sparrows, in the family Passerellidae, and from a few other birds sharing their name, such as the Java sparrow of the family Estrildidae. Many species nest on buildings and the house and Eurasian tree sparrows, in particular, inhabit cities in large numbers, so sparrows are among the most familiar of all wild birds. They are primarily seed-eaters, though they also consume small insects. Some species scavenge for food around cities and, like gulls or rock doves will happily eat virtually anything in small quantities.

2.4K
05 Dec 2022

Topic Review

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.

2.4K
25 Oct 2022

Topic Review

Benign Migratory Glossitis

Geographic tongue, also known by several other terms, is a condition of the mucous membrane of the tongue, usually on the dorsal surface. It is a common condition, affecting approximately 2–3% of the general population. It is characterized by areas of smooth, red depapillation (loss of lingual papillae) which migrate over time. The name comes from the map-like appearance of the tongue, with the patches resembling the islands of an archipelago. The cause is unknown, but the condition is entirely benign (importantly, it does not represent oral cancer), and there is no curative treatment. Uncommonly, geographic tongue may cause a burning sensation on the tongue, for which various treatments have been described with little formal evidence of efficacy.

2.4K
27 Sep 2022

Biography

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

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.

2.4K
04 Nov 2022

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

2.4K
30 Nov 2022

Topic Review

Thousand-Year Rose

The Thousand-year Rose (German: Tausendjähriger Rosenstock, literally: Thousand-year-old Rosebush) is also known as the Rose of Hildesheim. It grows on the apse of the Hildesheim Cathedral, a Catholic cathedral in Hildesheim, Germany, that is dedicated to the Assumption of Mary. The cathedral and the adjacent St. Michael's Church have been on the UNESCO list of World Heritage Sites since 1985. The rose that climbs on the wall of the cathedral's apse is believed to be the oldest living rose in the world. A Rosa canina, commonly known as a wild dog rose, grows against the eastern apse of the cathedral, which is around 21 metres (69 ft) high and 9 metres (30 ft) wide. The rose bush reaches a height of around 10 metres (33 ft) and documentation verifies its age at approximately 700 years. Slight variations arise in the tale of the establishment of the diocese by King Louis the Pious at Hildesheim in 815 but the rose bush is a common theme in all versions. The cathedral was destroyed by Allied bombers in 1945 during the Second World War, but the roots of the rose bush survived and it blossomed again among the ruins. According to legend, while the rose bush flourishes, Hildesheim will prosper. A poem about the rose was published in 1896. In the early twentieth century, after visiting the cathedral and seeing the rose, author Mabel Wagnalls was inspired to write a book, which went on to form the basis of a silent film.

2.4K
08 Nov 2022

Topic Review

List of Vaccine Topics

This is a list of vaccine-related topics. A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins. The agent stimulates the body's immune system to recognize the agent as foreign, destroy it, and "remember" it, so that the immune system can more easily recognize and destroy any of these microorganisms that it later encounters.

2.4K
04 Nov 2022

Biography

Stephen Emmott (born 3 June 1960) is a British scientist, entrepreneur and chief scientist of Scientific.[1][2] Emmott was named one of London's most influential scientists, and one of the most influential people in London by the Evening Standard in 2012.[3] Emmott studied at the University of York, where he completed a B.Sc. in Biological Sciences (experimental psychology), graduating in 198

2.4K
30 Dec 2022

Topic Review

Cerebrospinal Fluid Leak

A cerebrospinal fluid leak (CSF leak or CSFL) is a medical condition where the cerebrospinal fluid (CSF) surrounding the brain or spinal cord leaks out of one or more holes or tears in the dura mater. A cerebrospinal fluid leak can be either cranial or spinal, and these are two different disorders. A spinal CSF leak can be caused by one or more meningeal diverticula or CSF-venous fistulas not associated with an epidural leak. A CSF leak is either caused by trauma including that arising from medical interventions or spontaneously sometimes in those with predisposing conditions (known as a spontaneous cerebrospinal fluid leak or sCSF leak). Traumatic causes include a lumbar puncture noted by a post-dural-puncture headache, or a fall or other accident. Spontaneous CSF leaks are associated with heritable connective tissue disorders including Marfan syndrome and Ehlers–Danlos syndromes. A loss of CSF greater than its rate of production leads to a decreased volume inside the skull known as intracranial hypotension. Any CSF leak is most often characterized by orthostatic headaches, which worsen when standing, and improve when lying down. Other symptoms can include neck pain or stiffness, nausea, vomiting, dizziness, fatigue, and a metallic taste in the mouth. A CT myelography scan can identify the site of a cerebrospinal fluid leakage. Once identified, the leak can often be repaired by an epidural blood patch, an injection of the patient's own blood at the site of the leak, a fibrin glue injection, or surgery. The set of symptoms associated with a sCSF leak is referred to as a spontaneous cerebrospinal fluid leak syndrome (SCSFLS). A sCSF leak is uncommon but not rare, affecting at least one in 20,000 people and many more who go undiagnosed every year. On average, the condition develops at age 42, and women are twice as likely to be affected. Some people with a sCSF leak have a chronic leak of cerebrospinal fluid despite repeated patching attempts, leading to long-term disability due to pain and being unable to be upright, and surgery is often needed. SCSFLS was first described by German neurologist Georg Schaltenbrand in 1938 and by American neurologist Henry Woltman of the Mayo Clinic in the 1950s.

2.4K
11 Oct 2022

Topic Review

Interferon Gamma

Interferon gamma (IFN-γ) is a dimerized soluble cytokine that is the only member of the type II class of interferons. The existence of this interferon, which early in its history was known as immune interferon, was described by E. F. Wheelock as a product of human leukocytes stimulated with phytohemagglutinin, and by others as a product of antigen-stimulated lymphocytes. It was also shown to be produced in human lymphocytes. or tuberculin-sensitized mouse peritoneal lymphocytes challenged with Mantoux test (PPD); the resulting supernatants were shown to inhibit growth of vesicular stomatitis virus. Those reports also contained the basic observation underlying the now widely employed IFN-γ release assay used to test for tuberculosis. In humans, the IFN-γ protein is encoded by the IFNG gene.

2.4K
28 Apr 2023

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