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Biography
Cyrus Chothia
Cyrus Homi Chothia (19 February 1942 – 26 November 2019)[1] FRS[2][3] was an English biochemist who was an emeritus scientist at the Medical Research Council (MRC) Laboratory of Molecular Biology (LMB) at the University of Cambridge[4][5] and emeritus fellow of Wolfson College, Cambridge.[2][6][7][8][9][10][11] Chothia was educated at Alleyn's School,[12] then went to study at Durham Univer
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  • 16 Nov 2022
Biography
Hemant Mehta
Hemant Mehta (born February 25, 1983) is an American author, blogger, and atheist activist who gained fame for "selling his soul" on eBay.[1] Mehta is a regular speaker at atheist events and has sat on the boards of charitable organizations such as the Secular Student Alliance and the Foundation Beyond Belief. He also runs a blog on Patheos, Friendly Atheist, in which he and his associates publi
  • 1.8K
  • 02 Dec 2022
Topic Review
Polymorphism
In biology, polymorphism is the occurrence of two or more clearly different morphs or forms, also referred to as alternative phenotypes, in the population of a species. To be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (one with random mating). Put simply, polymorphism is when there are two or more possibilities of a trait on a gene. For example, there is more than one possible trait in terms of a jaguar's skin colouring; they can be light morph or dark morph. Due to having more than one possible variation for this gene, it is termed 'polymorphism'. However, if the jaguar has only one possible trait for that gene, it would be termed "monomorphic". For example, if there was only one possible skin colour that a jaguar could have, it would be termed monomorphic. The term polyphenism can be used to clarify that the different forms arise from the same genotype. Genetic polymorphism is a term used somewhat differently by geneticists and molecular biologists to describe certain mutations in the genotype, such as single nucleotide polymorphisms that may not always correspond to a phenotype, but always corresponds to a branch in the genetic tree. See below. Polymorphism is common in nature; it is related to biodiversity, genetic variation, and adaptation. Polymorphism usually functions to retain a variety of forms in a population living in a varied environment.:126 The most common example is sexual dimorphism, which occurs in many organisms. Other examples are mimetic forms of butterflies (see mimicry), and human hemoglobin and blood types. According to the theory of evolution, polymorphism results from evolutionary processes, as does any aspect of a species. It is heritable and is modified by natural selection. In polyphenism, an individual's genetic makeup allows for different morphs, and the switch mechanism that determines which morph is shown is environmental. In genetic polymorphism, the genetic makeup determines the morph. The term polymorphism also refers to the occurrence of structurally and functionally more than two different types of individuals, called zooids, within the same organism. It is a characteristic feature of cnidarians. For example, Obelia has feeding individuals, the gastrozooids; the individuals capable of asexual reproduction only, the gonozooids, blastostyles; and free-living or sexually reproducing individuals, the medusae. Balanced polymorphism refers to the maintenance of different phenotypes in population.
  • 1.8K
  • 07 Nov 2022
Biography
Frederick Wollaston Hutton
Captain Frederick Wollaston Hutton, FRS, (16 November 1836 – 27 October 1905) was an English-New Zealand scientist who applied the theory of natural selection to explain the origins and nature of the natural history of New Zealand. An army officer in early life, he then had an academic career in geology and biology. He became one of the most able and prolific nineteenth century naturalists of
  • 1.7K
  • 11 Nov 2022
Biography
Jerome R. Cox, Jr.
Jerome Rockhold Cox, Jr. (born May 24, 1925) is an American computer pioneer, scientist, and entrepreneur. He contributed significantly to the areas of biomedical computing, multimedia communications, and computer networking. He was the founding chairman of the Department of Computer Science at Washington University in St. Louis. He is a senior professor emeritus of Computer Science at Washingto
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  • 16 Dec 2022
Biography
William M. Jackson
William Morgan Jackson (born September 24, 1936) is a Distinguished Research and Emeritus Professor of Chemistry at University of California, Davis and pioneer in the field of astrochemistry. His work considers cometary astrochemistry and the development of laser photochemistry to understand planetary atmospheres. He is a Fellow of the American Association for the Advancement of Science, the Ame
  • 1.7K
  • 26 Dec 2022
Biography
Lynn Townsend White Jr.
Lynn Townsend White Jr. (April 29, 1907 – March 30, 1987) was an American historian. He was a professor of medieval history at Princeton from 1933 to 1937, and at Stanford from 1937 to 1943. He was president of Mills College, Oakland, from 1943 to 1958 and a professor at University of California, Los Angeles from 1958 until 1987.[1] Lynn White helped to found The Society of History and Technol
  • 1.7K
  • 15 Dec 2022
Topic Review
Embryogenesis
Embryogenesis is the process by which the embryo forms and develops. In mammals, the term refers chiefly to early stages of prenatal development, whereas the terms fetus and fetal development describe later stages. Embryogenesis starts with the fertilization of the egg cell (ovum) by a sperm cell, (spermatozoon). Once fertilized, the ovum is referred to as a zygote, a single diploid cell. The zygote undergoes mitotic divisions with no significant growth (a process known as cleavage) and cellular differentiation, leading to development of a multicellular embryo. Although embryogenesis occurs in both animal and plant development, this article addresses the common features among different animals, with some emphasis on the embryonic development of vertebrates and mammals.
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  • 10 Nov 2022
Biography
Susana Martinez-Conde
Susana Martinez-Conde (born October 1, 1969) is a neuroscientist and science writer. She is a professor of ophthalmology, neurology, and physiology & pharmacology at the State University of New York, Downstate Medical Center, where she directs the Laboratory of Integrative Neuroscience. She directed laboratories previously at the Barrow Neurological Institute and University College London.[1] He
  • 1.7K
  • 28 Nov 2022
Biography
Milovan Đilas
Milovan Đilas (pronounced [mîlɔʋan dʑîlaːs]; usually spelled Djilas in English-language publications; Serbian Cyrillic: Милован Ђилас; 12 June 1911 – 20 April 1995) was a Yugoslav communist politician, theorist and author. He was a key figure in the Partisan movement during World War II, as well as in the post-war government. A self-identified democratic socialist,[1] Đila
  • 1.7K
  • 15 Nov 2022
Topic Review
Malting Process
The malting process converts raw grain into malt. The malt is mainly used for brewing or whisky making, but can also be used to make malt vinegar or malt extract. Various grains are used for malting; the most common are barley, sorghum, wheat and rye. There are a number of different types of equipment that can be used to produce the malt. A traditional floor malting germinates the grains in a thin layer on a solid floor, and the grain is manually raked and turned to keep the grains loose and aerated. In a modern malt house the process is more automated, and the grain is germinated on a floor that is slotted to allow air to be forced through the grain bed. Large mechanical turners keep the much thicker bed loose with higher productivity and better energy efficiency.
  • 1.7K
  • 11 Oct 2022
Topic Review
Cashew Production in Tanzania
Tanzania is one of the largest cashew producers in Africa, with exports providing 10-15 percent of the country's foreign exchange. The country is the eighth-largest grower of cashew nut in the world and ranks fourth in Africa. The country provides 20% of Africa's cashew nut and only trails in production of Nigeria, Cote D'Ivoire, and Guinea-Bissau, according to figures released in 2012 by United Nations Food and Agricultural Organisation (FAO). The country has been engaged in the production of the cash crop since before independence in the years 1960s however, poor regulation and lack of reliable payments to farmers have posed significant challenges to the Cashew Nut farming industry in Tanzania. Guinea-Bissau, a country a tenth of the area of Tanzania's, has a significantly greater yield. The cash crop is usually cultivated in the southern coastal regions of the country, near the towns of Mtwara, Kilwa and Dar es Salaam. The sale and marketing of the product is run by the Cashewnut Board of Tanzania, through various farmer co-operatives. More than ninety percent of the exports are destined for India and almost entirely in raw form. The lack of domestic processing firms costs the country vital foreign revenues and thousands of jobs. The Tanzanian government has been facing challenges for finding potential investors in order to revive the cashew processing industry in Tanzania.
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  • 16 Nov 2022
Topic Review
Amenorrhea
Amenorrhea is the absence of a menstrual period in a woman of reproductive age. Physiological states of amenorrhoea are seen, most commonly, during pregnancy and lactation (breastfeeding). Outside the reproductive years, there is absence of menses during childhood and after menopause. Amenorrhoea is a symptom with many potential causes. Primary amenorrhea is defined as an absence of secondary sexual characteristics by age 13 with no menarche or normal secondary sexual characteristics but no menarche by 15 years of age. It may be caused by developmental problems, such as the congenital absence of the uterus, failure of the ovary to receive or maintain egg cells, or delay in pubertal development. Secondary amenorrhoea, ceasing of menstrual cycles after menarche, is defined as the absence of menses for three months in a woman with previously normal menstruation, or six months for women with a history of oligomenorrhoea. It is often caused by hormonal disturbances from the hypothalamus and the pituitary gland, premature menopause, intrauterine scar formation, or eating disorders.
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  • 28 Sep 2022
Biography
Guillermo Söhnlein
Guillermo Adrian Miguel Söhnlein (born May 18, 1966 in Buenos Aires, Argentina) is an American social entrepreneur with special interests in the commercialization of outer space, the exploration of the world's oceans, and the global connections between space and ocean industries. Guillermo Söhnlein was born in Buenos Aires, Argentina , on May 18, 1966. He immigrated to the United States in
  • 1.7K
  • 01 Dec 2022
Topic Review
Living Root Bridges
Template:Infobox bridge Living root bridges are a form of tree shaping common in the southern part of the Northeast Indian state of Meghalaya. They are handmade from the aerial roots of rubber fig trees (Ficus elastica) by the Khasi and Jaintia peoples of the mountainous terrain along the southern part of the Shillong Plateau. Root bridges have also been observed in the Indian state of Nagaland. Living root bridges have also been created in Indonesia at Jembatan akar on the island of Sumatra, and in the banten provence of Java , by the Baduy people.
  • 1.7K
  • 21 Nov 2022
Biography
Emil Georg Cohn
Emil Georg Cohn (28 September 1854 – 28 January 1944), was a German physicist. Cohn was born in Neustrelitz, Mecklenburg on 28 September 1854. He was the son of August Cohn, a lawyer, and Charlotte Cohn. At the age of 17, Cohn began to study jurisprudence at the University of Leipzig. However, at the Ruprecht Karl University of Heidelberg and the University of Strasbourg he began to study p
  • 1.7K
  • 30 Dec 2022
Topic Review
Discriminative Measurement for Radon Isotopes
Radon and thoron measurement studies have been widely conducted and reported all over the world. Generally, the techniques used relate to the passive nuclear track detectors. Though some surveys shown that passive monitors for radon are sensitive to thoron, and hence the measured results might be probably overestimated the radon concentration. This study investigated the radon and thoron measurement in domestic and international using passive radon-thoron discriminative measuring device, commercially named RADUET. This paper attempts to provide an understanding and evident roadmap for discriminative measurements of radon isotopes.
  • 1.7K
  • 05 Nov 2020
Biography
Robert J. Lang
Robert J. Lang (born May 4, 1961) is an United States physicist who is also one of the foremost origami artists and theorists in the world. He is known for his complex and elegant designs, most notably of insects and animals. He has studied the mathematics of origami and used computers to study the theories behind origami. He has made great advances in making real-world applications of origami t
  • 1.7K
  • 21 Nov 2022
Topic Review
Megapnosaurus Rhodesiensis
Coelophysis rhodesiensis is an extinct species of coelophysid theropod dinosaur that lived approximately 188 million years ago during the early part of the Jurassic Period in what is now Africa. The species was a small to medium-sized, lightly built, ground-dwelling, bipedal carnivore, that could grow up to 3 m (9.8 ft) long. It was formerly called Syntarsus, but that name was already taken by a beetle, and was subsequently given the name Megapnosaurus by Ivie, Ślipiński & Węgrzynowicz, in 2001, though many subsequent studies have classified it in the genus Coelophysis.
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  • 28 Nov 2022
Topic Review
Outline of Biophysics
The following outline is provided as an overview of and topical guide to biophysics: Biophysics – interdisciplinary science that uses the methods of physics to study biological systems.
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  • 02 Nov 2022
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