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Biography

Osaretin Agbonavbare

Osaretin Agbonavbare (born 14 October 1992) is a young Nigerian innovative serial entrepreneur. He is the COO and founder [1][2][3] [4][5][6] of bbcmgtAI, a pan African AI software company that empowered Entrepreneurs across the continent and beyond with advance digital technology. [7][8] He is one of the intending winners of Tony Elumelu Foundation (TEF) $5000 grant 2022 and African Genius Awar

2.2K
06 Dec 2022

Topic Review

Gastro- is a common English-language prefix derived from the ancient Greek γαστήρ gastēr ("stomach").

2.2K
25 Oct 2022

Biography

Herman Russell Branson (August 14, 1914 – June 7, 1995) was an African-American physicist, chemist, best known for his research on the alpha helix protein structure, and was also the president of two colleges. Branson received his B.S. from Virginia State College in 1936, and his Ph.D. in physics from the University of Cincinnati, under the direction of Boris Padolsky, in 1939. His thesis w

2.2K
15 Dec 2022

Topic Review

Live Attenuated Influenza Vaccine

Live attenuated influenza vaccine (LAIV) is a type of influenza vaccine in the form of a nasal spray that is recommended for the prevention of influenza. It is an attenuated vaccine, unlike most influenza vaccines, which are inactivated vaccines. LAIV is administered intranasally, while inactivated vaccines are administered by intramuscular injection. LAIV is sold under the brand name FluMist Quadrivalent in the United States and the brand name Fluenz Tetra in the European Union. FluMist was first introduced in 2003 by MedImmune.

2.2K
24 Nov 2022

Topic Review

Necrotizing Ulcerative Stomatitis

Acute necrotizing ulcerative gingivitis (ANUG) is a common, non-contagious infection of the gums with sudden onset. The main features are painful, bleeding gums, and ulceration of inter-dental papillae (the sections of gum between adjacent teeth). This disease, along with necrotizing (ulcerative) periodontitis (NP or NUP) is classified as a necrotizing periodontal disease, one of the seven general types of gum disease caused by inflammation of the gums (periodontitis). The often severe gum pain that characterizes ANUG distinguishes it from the more common chronic periodontitis which is rarely painful. If ANUG is improperly treated or neglected, it may become chronic and/or recurrent. The causative organisms are mostly anaerobic bacteria, particularly Fusobacteriota and spirochete species. Predisposing factors include poor oral hygiene, smoking, poor nutrition, psychological stress, and a weakened immune system. When the attachments of the teeth to the bone are involved, the term NUP is used. Treatment of ANUG is by removal of dead gum tissue and antibiotics (usually metronidazole) in the acute phase, and improving oral hygiene to prevent recurrence. Although the condition has a rapid onset and is debilitating, it usually resolves quickly and does no serious harm. The informal name trench mouth arose during World War I as many soldiers developed the disease, probably because of the poor conditions and extreme psychological stress.

2.2K
04 Nov 2022

Biography

Władysław Minor also known as Wladek Minor (born 1946) is a Polish-American biophysicist, a specialist in structural biology and protein crystallography. He is a Harrison Distinguished Professor of Molecular Physiology and Biological Physics at the University of Virginia.[1] Minor is a co-author of HKL2000/HKL3000 – crystallographic data processing and structure solution software used to pro

2.2K
06 Dec 2022

Biography

Sarah Haider is a Pakistani-American writer, speaker, and political activist.[1] She created the advocacy group Ex-Muslims of North America (EXMNA) which seeks to normalize religious dissent and to help former Muslims leave the religion by linking them to support networks.[2] She is the co-founder and director of development for EXMNA.[3] Haider was born in Karachi, Pakistan , in a practicing

2.2K
28 Nov 2022

Topic Review

List of Amphibians

List of amphibians organizes the class of amphibian by family and subfamilies and mentions the number of species in each of them. The list below largely follows Darrel Frost's Amphibian Species of the World (ASW), Version 5.5 (31 January 2011). Another classification, which largely follows Frost, but deviates from it in part is the one of AmphibiaWeb, by the University of California, Berkeley. The major differences between these two classifications are:

2.2K
25 Oct 2022

Topic Review

In evolutionary biology, a spandrel is a phenotypic trait that is a byproduct of the evolution of some other characteristic, rather than a direct product of adaptive selection. Stephen Jay Gould and Richard Lewontin brought the term into biology in their 1979 paper "The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme". Adaptationism is a point of view that sees most organismal traits as adaptive products of natural selection. Gould and Lewontin sought to temper what they saw as adaptationist bias by promoting a more structuralist view of evolution. The term "spandrel" originates from architecture, where it refers to the roughly triangular spaces between the top of an arch and the ceiling.

2.2K
26 Oct 2022

Topic Review

Hyraxes (from grc ὕραξ (Script error: No such module "Ancient Greek".) 'shrewmouse'), also called dassies, are small, thickset, herbivorous mammals in the order Hyracoidea. Hyraxes are well-furred, rotund animals with short tails. Typically, they measure between 30 and 70 cm (12 and 28 in) long and weigh between 2 and 5 kg (4 and 11 lb). They are superficially similar to pikas and marmots, but are more closely related to elephants and sea cows. Hyraxes have a life span from 9 to 14 years. Five extant species are recognised: the rock hyrax (Procavia capensis) and the yellow-spotted rock hyrax (Heterohyrax brucei), which both live on rock outcrops, including cliffs in Ethiopia and isolated granite outcrops called koppies in southern Africa; the western tree hyrax (Dendrohyrax dorsalis), southern tree hyrax (D. arboreus), and eastern tree hyrax (D. validus). Their distribution is limited to Africa, except for P. capensis, which is also found in the Middle East.

2.2K
14 Oct 2022

Biography

David Orlin Hestenes, Ph.D. (born May 21, 1933) is a theoretical physicist and science educator. He is best known as chief architect of geometric algebra as a unified language for mathematics and physics,[1] and as founder of Modelling Instruction, a research-based program to reform K–12 Science, Technology, Engineering, and Mathematics (STEM) education.[2] For more than 30 years, he was empl

2.1K
30 Dec 2022

Biography

Johann Friedrich Blumenbach

Johann Friedrich Blumenbach (11 May 1752 – 22 January 1840) was a German physician, naturalist, physiologist, and anthropologist. He was one of the first to explore the study of the human being as an aspect of natural history. His teachings in comparative anatomy were applied to his classification of human races, of which he claimed there were five, Caucasian, Mongolian, Malayan, Ethiopian, an

2.1K
16 Nov 2022

Biography

James Van Allen

James Alfred Van Allen (September 7, 1914 – August 9, 2006) was an American space scientist at the University of Iowa. He was instrumental in establishing the field of magnetospheric research in space. The Van Allen radiation belts were named after him, following their discovery by his Geiger–Müller tube instruments on the 1958 satellites: (Explorer 1, Explorer 3, and Pioneer 3)[1][2][3]

2.1K
17 Nov 2022

Biography

Sankara Bhagavadpada

Dr. Sankara Bhagavadpada [1] is an Indian Advaitic spiritual teacher, author & Vedic astrologer[2] from Chennai, Tamil Nadu, India.[3] Dr. Sankara Bhagavadpada was born Shankar Ramachandran, on May 1, 1948 in Madras, India. In his boyhood years, he came under the benevolent spiritual & philosophical influence of his mother and his philosopher-friend Sri Bhagavan.[4] In 1971, he secured his M

2.1K
27 Dec 2022

Topic Review

Passive Electrolocation in Fish

Passive electrolocation is a process where certain species of fish or aquatic amphibians can detect electric fields using specialized electroreceptors to detect and to locate the source of an external electric field in its environment creating the electric field. These external electric fields can be produced by any bioelectrical process in an organism, especially by actions of the nerves or muscles of fish, or indeed by the specially developed electric organs of fish. Other fields are induced by movement of a conducting organism through the earth's magnetic field, or from atmospheric electricity. Electrolocating fish use this ability to detect prey, locate other fish, avoid predators, and perhaps to navigate by the Earth's magnetic field. Electroreceptors probably evolved once or twice early in vertebrate evolution, but the sense was apparently lost in amniotes, and in a large number of the Actinopterygii (ray finned fishes) only to reappear independently in two teleost clades. In fish, the ampullary receptor is a specialized receptor that it uses to sense these electric fields and allows the fish to follow electric field lines to their source. Sharks primarily use specialized receptors, called Ampullae of Lorenzini, to detect their prey's low frequency DC fields and may also use their receptors in navigation by the Earth's magnetic field. Weakly electric fish use their ampullary receptors and tuberous receptors to detect the weakly electric fields produced by other fish, as well as for possible predator avoidance. Passive electrolocation contrasts with active electrolocation, in which the animal emits its own weak self generated electric field and detects nearby objects by detecting the distortion of its produced electric field. In active electrolocation the animal senses its own electromotor discharge or reafference instead of some externally generated electric field or discharge.

2.1K
17 Oct 2022

Topic Review

Project 4.1 was the designation for a medical study conducted by the United States of those residents of the Marshall Islands exposed to radioactive fallout from the March 1, 1954 Castle Bravo nuclear test at Bikini Atoll, which had an unexpectedly large yield. Government and mainstream historical sources point to the study being organized on March 6 or March 7, 1954, six days after the Bravo shot.

2.1K
07 Nov 2022

Biography

Claude Pouillet

Claude Servais Mathias Pouillet (16 February 1790 – 14 June 1868) was a France physicist and a professor of physics at the Sorbonne and member of the French Academy of Sciences (elected 1837). He studied sciences at the École normale supérieure (Paris), and from 1829 to 1849 was associated with the Conservatoire national des arts et métiers, first as a professor, and beginning in 1832, a

2.1K
24 Nov 2022

Biography

Joseph A. Walker

Joseph Albert Walker (February 20, 1921 – June 8, 1966) flew the world's first two spaceplane flights in 1963, thereby becoming the United States' seventh man in space. Walker was a Captain in the United States Air Force , an American World War II pilot, an experimental physicist, a NASA test pilot, and a member of the U.S. Air Force Man In Space Soonest spaceflight program. His two X-15 exper

2.1K
15 Nov 2022

Topic Review

RNA World Hypothesis

The RNA world hypothesis proposes that RNA was the first life-form on earth, later developing a cell membrane around it and becoming the first prokaryotic cell.

2.1K
07 Nov 2022

Biography

Yuko Tojo (東條由布子, Tōjō Yūko, May 20, 1939 (Keijo, Japanese Korea) – February 13, 2013, Tokyo, Japan) was a Japanese ultra-nationalist politician, Imperial Japanese apologist, and brief political hopeful.[1] She was the granddaughter of General Hideki Tōjō, the Japanese wartime prime minister who was convicted of planning and orchestrating most of the major Japanese acts of aggr

2.1K
20 Dec 2022

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