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Topic Review
Structuralism
Biological or process structuralism is a school of biological thought that objects to an exclusively Darwinian or adaptationist explanation of natural selection such as is described in the 20th century's modern synthesis. It proposes instead that evolution is guided differently, basically by more or less physical forces which shape the development of an animal's body, and sometimes implies that these forces supersede selection altogether. Structuralists have proposed different mechanisms that might have guided the formation of body plans. Before Darwin, Étienne Geoffroy Saint-Hilaire argued that animals shared homologous parts, and that if one was enlarged, the others would be reduced in compensation. After Darwin, D'Arcy Thompson hinted at vitalism and offered geometric explanations in his classic 1917 book On Growth and Form. Adolf Seilacher suggested mechanical inflation for "pneu" structures in Ediacaran biota fossils such as Dickinsonia. Günter P. Wagner argued for developmental bias, structural constraints on embryonic development. Stuart Kauffman favoured self-organisation, the idea that complex structure emerges holistically and spontaneously from the dynamic interaction of all parts of an organism. Michael Denton argued for laws of form by which Platonic universals or "Types" are self-organised. Stephen J. Gould and Richard Lewontin proposed biological "spandrels", features created as a byproduct of the adaptation of nearby structures. Gerd B. Müller and Stuart A. Newman argued that the appearance in the fossil record of most of the current phyla in the Cambrian explosion was "pre-Mendelian"[lower-alpha 1] evolution caused by physical factors. Brian Goodwin, described by Wagner as part of "a fringe movement in evolutionary biology", denies that biological complexity can be reduced to natural selection, and argues that pattern formation is driven by morphogenetic fields. Darwinian biologists have criticised structuralism, emphasising that there is plentiful evidence both that natural selection is effective and, from deep homology, that genes have been involved in shaping organisms throughout evolutionary history. They accept that some structures such as the cell membrane self-assemble, but deny the ability of self-organisation to drive large-scale evolution.
  • 2.0K
  • 30 Nov 2022
Biography
Ewan Birney
John Frederick William Birney (known as Ewan) (born 6 December 1972)[1][2][3][4] CBE FRS FMedSci[5][6] is joint director with Rolf Apweiler of the European Bioinformatics Institute (EBI),[7][8][9] part of the European Molecular Biology Laboratory (EMBL) in Hinxton, Cambridgeshire. He also serves as non-executive director of Genomics England, chair of the Global Alliance for Genomics and Health (
  • 2.0K
  • 08 Dec 2022
Biography
Thomas Johann Seebeck
Thomas Johann Seebeck (German; 9 April 1770 – 10 December 1831) was a Baltic German physicist, who, in 1822, observed a relationship between heat and magnetism. Later, in 1823, Ørsted called this phenomenon thermoelectric effect. Seebeck was born in Reval (today Tallinn, Estonia) to a wealthy Baltic German merchant family. He received a medical degree in 1802 from the University of Göttinge
  • 1.9K
  • 15 Nov 2022
Biography
Amir Taheri
Amir Taheri (born 9 June 1942 in Ahvaz) is an Iranian-born conservative[1] author based in Europe. His writings focus on the Middle East affairs and topics related to islamic terrorism. He has been the subject of many controversies involving fabrications in his writings, most notable of which was the 2006 Iranian sumptuary law controversy. He is the current Chairman of Gatestone Institute in Eur
  • 1.9K
  • 08 Dec 2022
Topic Review
Thalattosaur
Thalattosauria (meaning "ocean lizards") is an extinct order of prehistoric marine reptiles that lived in the middle to late Triassic period. Thalattosaurs were diverse in size and shape, and are divided into two superfamilies: Askeptosauroidea and Thalattosauroidea. Askeptosauroids were endemic to the Tethys Ocean, their fossils have been found in Europe and China, and they were likely semiaquatic fish eaters with straight snouts and decent terrestrial abilities. Thalattosauroids were more specialized for aquatic life and most had unusual downturned snouts and crushing dentition. Thalattosauroids lived along the coasts of both Panthalassa and the Tethys Ocean, and were most diverse in China and western North America. The largest species of thalattosaurs grew to over 4 meters (13 feet) in length, including a long, flattened tail utilized in underwater propulsion. Although thalattosaurs bore a superficial resemblance to lizards, their exact relationships are unresolved. They are widely accepted as diapsids, but experts have variously placed them on the reptile family tree among Lepidosauromorpha (lizards and their relatives), Archosauromorpha (archosaurs and their relatives), ichthyosaurs, and/or other marine reptiles.
  • 1.9K
  • 25 Nov 2022
Biography
Manfred von Ardenne
Manfred von Ardenne (20 January 1907 – 26 May 1997) was a German researcher and applied physicist and inventor. He took out approximately 600 patents in fields including electron microscopy, medical technology, nuclear technology, plasma physics, and radio and television technology. From 1928 to 1945, he directed his private research laboratory Forschungslaboratorium für Elektronenphysik. For
  • 1.9K
  • 15 Nov 2022
Biography
Arthur Gordon Webster
Arthur Gordon Webster (November 28, 1863 – May 15, 1923), physicist, was a founder and president of the American Physical Society. Arthur Gordon Webster was born on 28 November 1863 at Brookline, Massachusetts to William Edward Webster and Mary Shannon Davis. On 8 October 1889 he married Elizabeth Munroe Townsend, daughter of Captain Robert Townsend and Harriett Munro of Albany, New York.[1
  • 1.9K
  • 27 Dec 2022
Topic Review
Benign Migratory Stomatitis
Geographic tongue, also known by several other terms,[note 1] 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.
  • 1.9K
  • 24 Nov 2022
Biography
Giacomo Mauro D’Ariano
Giacomo Mauro D’Ariano (born 11 May 1955) is an Italian quantum physicist. He is a professor of theoretical physics at the University of Pavia, where he is the leader of the QUIT (Quantum Information Theory) group.[1][2] He is a member of the Center of Photonic Communication and Computing at Northwestern University;[3] a member of the Istituto Lombardo Accademia di Scienze e Lettere; and a mem
  • 1.9K
  • 16 Nov 2022
Biography
Fernando Holiday
Fernando Silva Bispo, better known as Fernando Holiday (September 22, 1996) is a Brazilian politician affiliated with Democratas (DEM) and councilor of the city of São Paulo.[1] He was elected with 48,055 votes in the 2016 elections,[2] and became the first openly gay councilor.[3] He is the national coordinator of the Free Brazil Movement (MBL) and a law student.[4][5] Holiday became known fo
  • 1.9K
  • 07 Dec 2022
Topic Review
Recall (Memory)
Recall in memory refers to the mental process of retrieval of information from the past. Along with encoding and storage, it is one of the three core processes of memory. There are three main types of recall: free recall, cued recall and serial recall. Psychologists test these forms of recall as a way to study the memory processes of humans and animals. Two main theories of the process of recall are the two-stage theory and the theory of encoding specificity.
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  • 03 Nov 2022
Topic Review
Postbiotics
Postbiotics include any substance released by or produced through the metabolic activity of the microorganism, which exerts a beneficial effect on the host, directly or indirectly. As postbiotics do not contain live microorganisms, the risks associated with their intake are minimized. Postbiotics play a vital role in the maturation of the immune system, affect barrier tightness and the intestinal ecosystem, and indirectly shape the structure of the microbiota. Postbiotics display pleiotropic effects, including their immunomodulatory, anti-inflammatory, antioxidant, and anti-cancer properties. As such, postbiotics may be useful in treating or preventing many disease entities, including those for which effective causal therapy has not yet been found.
  • 1.9K
  • 05 Nov 2020
Topic Review
Atriplex Portulacoides as Functional Food
The halophyte Atriplex portulacoides (syn. Halimione portulacoides) occurs in habitats that are exposed to seawater inundations, and shows biochemical adaptations to saline and oxidative stresses. Its composition includes long chain lipids, sterols, phenolic compounds, glutathione, carotenoids,and micronutrients such as Fe, Zn, Co and Cu. The productivity of A. portulacoides in natural environments, and its adaptability to non-saline soils, make it a potential crop of high economic interest. This plant is suitable to be exploited as a functional food that is potentially able to reduce oxidative stress and inflammatory processes in humans and animals. This plant offers a valuable example of valorisation of the biodiversity for promoting the sustainability and diversification in agriculture.
  • 1.9K
  • 26 Nov 2020
Topic Review
Function
In evolutionary biology, function is the reason some object or process occurred in a system that evolved through natural selection. That reason is typically that it achieves some result, such as that chlorophyll helps to capture the energy of sunlight in photosynthesis. Hence, the organism that contains it is more likely to survive and reproduce, in other words the function increases the organism's fitness. A characteristic that assists in evolution is called an adaptation; other characteristics may be non-functional spandrels, though these in turn may later be co-opted by evolution to serve new functions. In biology, function has been defined in many ways. In physiology, it is simply what an organ, tissue, cell or molecule does. In the philosophy of biology, talk of function inevitably suggests some kind of teleological purpose, even though natural selection operates without any goal for the future. All the same, biologists often use teleological language as a shorthand for function. In contemporary philosophy of biology, there are three major accounts of function in the biological world: theories of causal role, selected effect, and goal contribution.
  • 1.9K
  • 28 Oct 2022
Biography
Leslie Coleman
Leslie Charles Coleman (16 June 1878 – 14 September 1954) was a Canadian entomologist, plant pathologist and virologist who worked as the first director of agriculture in Mysore State in southern India. He conducted pioneering research on the pests and diseases affecting agriculture in the region and was instrumental in establishing several agricultural research institutions including the Univ
  • 1.9K
  • 09 Dec 2022
Biography
Maria Goeppert-Mayer
Maria Goeppert Mayer (June 28, 1906 – February 20, 1972) was a German-born American theoretical physicist, and Nobel laureate in Physics for proposing the nuclear shell model of the atomic nucleus. She was the second woman to win a Nobel Prize in physics, the first being Marie Curie. A graduate of the University of Göttingen, Goeppert Mayer wrote her doctoral thesis on the theory of possible
  • 1.9K
  • 28 Nov 2022
Topic Review
Single Molecule Real Time Sequencing
Single molecule real time sequencing (SMRT) is a parallelized single molecule DNA sequencing method. Single molecule real time sequencing utilizes a zero-mode waveguide (ZMW). A single DNA polymerase enzyme is affixed at the bottom of a ZMW with a single molecule of DNA as a template. The ZMW is a structure that creates an illuminated observation volume that is small enough to observe only a single nucleotide of DNA being incorporated by DNA polymerase. Each of the four DNA bases is attached to one of four different fluorescent dyes. When a nucleotide is incorporated by the DNA polymerase, the fluorescent tag is cleaved off and diffuses out of the observation area of the ZMW where its fluorescence is no longer observable. A detector detects the fluorescent signal of the nucleotide incorporation, and the base call is made according to the corresponding fluorescence of the dye.
  • 1.9K
  • 01 Nov 2022
Biography
Olavo de Carvalho
Olavo Luiz Pimentel de Carvalho (born 29 April 1947)[1] is a Brazil ian journalist and essayist. His interests include historical philosophy, the history of revolutionary movements, the traditionalist school[2] and comparative religion.[3][4] He is known for his conservative and right-wing political stance, and for being a critic of the political Left.[5][6][7][8][9][10][11][12] He is an advocat
  • 1.9K
  • 21 Nov 2022
Topic Review
Osteoclasts and Osteoblasts
The bone is a complex organ that is dependent on a tight regulation between bone formation by osteoblasts (OBs) and bone resorption by osteoclasts (OCs). The OC is a multinucleated giant cell, arising from the fusion of many mononuclear OC precursors with a myeloid/monocyte origin. Differently from OCs, OBs arise from pluripotent mesenchymal stem cells (MSCs). The main function of OBs is the synthesis of new bone matrix. Bone metabolism is regulated by various hormones or cytokines and dysregulation in this complex system can lead to numerous diseases characterized either by enhanced bone resorption (osteoporotic phenotype) or enhanced bone formation (osteopetrotic phenotype).
  • 1.9K
  • 09 May 2021
Topic Review
Periphylla
The helmet jellyfish (Periphylla periphylla) is a luminescent, red-colored jellyfish of the deep sea, belonging to the order Coronatae of the phylum Cnidaria. It is the only species in the monotypic genus Periphylla. They are the only known scyphozoan to undergo sexual propagation that lacks a planula stage. Not only is their reproductive cycle unique, so are their living conditions. They are found in deeper parts of the ocean due to them being photophobic.
  • 1.9K
  • 27 Oct 2022
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