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Arnold Adolph Berthold
Arnold Adolph Berthold (also Arnold Adolf Berthold) (26 February 1803, in Soest – 3 January 1861, in Göttingen) was a German scientist, most notably a physiologist and zoologist . He is best known in modern science for his pioneering experiments in the field of endocrinology. He published works on herpetology, ornithology, entomology and chemistry. Early life and education Berthold was the second-youngest of six children. His father was a carpenter and his family was not wealthy. He went to the local '' gymnasium'' (equivalent to a grammar school) where he studied the classics but was most interested in natural history. He followed his older brother's example to study medicine at University of Göttingen in August 1819. His thesis was under the direction of Johann Friedrich Blumenbach (1752–1840) and he qualified on 10 September 1823. Career He remained at Göttingen for a year before doing a tour of other universities and clinics, which included meeting Johann Lukas Sch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soest, Germany
Soest (, as if it were 'Sohst'; Westphalian: ''Saust'') is a city in North Rhine-Westphalia, Germany. It is the capital of the Soest district. Geography Soest is located along the ''Hellweg'' road, approximately south-west of Lippstadt, roughly east of Dortmund and roughly west of Paderborn. Neighbouring places *Bad Sassendorf *Ense *Lippetal *Möhnesee *Werl *Welver Legends The Norwegian Þiðrekssaga from the 13th century, a series of tales about the Gothic King Theoderic the Great, identifies Soest (called Susat) as the capital of Attila's (?–453) Hunnic Empire. The actual location of Attila's capital has not been determined. History Owing to its fertile soil (predominantly brown silty clay loam), the area around Soest is believed to have been settled well before the village is first mentioned in the ''Dagobertsche Schenkung'' in 836. Excavations in recent decades have uncovered signs of habitation stretching back more than 4000 years. During the 11th and 12th ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Friedrich Blumenbach
Johann Friedrich Blumenbach (11 May 1752 – 22 January 1840) was a German physician, naturalist, physiologist, and anthropologist. He is considered to be a main founder of zoology and anthropology as comparative, scientific disciplines. He was also important as a race theorist. 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, and American. He was a member of what modern historians call the Göttingen School of History. Blumenbach's peers considered him one of the great theorists of his day, and he was a mentor or influence on many of the next generation of German biologists, including Alexander von Humboldt. Early life and education Blumenbach was born at his family house in Gotha. His father was Heinrich Blumenbach, a local school headmaster; his mother was Cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Oxide
Iron oxides are chemical compounds composed of iron and oxygen. Several iron oxides are recognized. All are black magnetic solids. Often they are non-stoichiometric. Oxyhydroxides are a related class of compounds, perhaps the best known of which is rust. Iron oxides and oxyhydroxides are widespread in nature and play an important role in many geological and biological processes. They are used as iron ores, pigments, catalysts, and in thermite, and occur in hemoglobin. Iron oxides are inexpensive and durable pigments in paints, coatings and colored concretes. Colors commonly available are in the "earthy" end of the yellow/orange/red/brown/black range. When used as a food coloring, it has E number E172. Stoichiometries Iron oxides feature as ferrous ( Fe(II)) or ferric ( Fe(III)) or both. They adopt octahedral or tetrahedral coordination geometry. Only a few oxides are significant at the earth's surface, particularly wüstite, magnetite, and hematite. * Oxides of FeII ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Bunsen
Robert Wilhelm Eberhard Bunsen (; 30 March 1811 – 16 August 1899) was a German chemist. He investigated emission spectra of heated elements, and discovered caesium (in 1860) and rubidium (in 1861) with the physicist Gustav Kirchhoff. The Bunsen–Kirchhoff Award for spectroscopy is named after Bunsen and Kirchhoff. Bunsen also developed several gas-analytical methods, was a pioneer in photochemistry, and did early work in the field of organic arsenic chemistry. With his laboratory assistant Peter Desaga, he developed the Bunsen burner, an improvement on the laboratory burners then in use. Early life and education Bunsen was born in Göttingen, Germany in 1811, in what is now the state of Lower Saxony in Germany. Bunsen was the youngest of four sons of the University of Göttingen's chief librarian and professor of modern philology, Christian Bunsen (1770–1837). After attending school in Holzminden, Bunsen matriculated at Göttingen in 1828 and studied chemistry with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermaphrodite
In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrates) do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which either partner can act as the female or male. For example, the great majority of tunicata, tunicates, pulmonate molluscs, opisthobranch, earthworms, and slugs are hermaphrodites. Hermaphroditism is also found in some fish species and to a lesser degree in other vertebrates. Most plants are also hermaphrodites. Animal species having different sexes, male and female, are called Gonochorism, gonochoric, which is the opposite of hermaphrodite. There are also species where hermaphrodites exist alongside males (called androdioecy) or alongside females (called gynodioecy), or all three exist in the same species ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myopia
Near-sightedness, also known as myopia and short-sightedness, is an eye disease where light focuses in front of, instead of on, the retina. As a result, distant objects appear blurry while close objects appear normal. Other symptoms may include headaches and eye strain. Severe near-sightedness is associated with an increased risk of retinal detachment, cataracts, and glaucoma. The underlying mechanism involves the length of the eyeball growing too long or less commonly the lens being too strong. It is a type of refractive error. Diagnosis is by eye examination. Tentative evidence indicates that the risk of near-sightedness can be decreased by having young children spend more time outside. This decrease in risk may be related to natural light exposure. Near-sightedness can be corrected with eyeglasses, contact lenses, or a refractive surgery. Eyeglasses are the easiest and safest method of correction. Contact lenses can provide a wider field of vision, but are associated with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Privatdozent
''Privatdozent'' (for men) or ''Privatdozentin'' (for women), abbreviated PD, P.D. or Priv.-Doz., is an academic title conferred at some European universities, especially in German-speaking countries, to someone who holds certain formal qualifications that denote an ability (''facultas docendi'') and permission to teach (''venia legendi'') a designated subject at the highest level. To be granted the title Priv.-Doz. by a university, a recipient has to fulfill the criteria set by the university which usually require excellence in research, teaching, and further education. In its current usage, the title indicates that the holder has completed their habilitation and is therefore granted permission to teach and examine students independently without having a professorship. Conferment and roles A university faculty can confer the title to an academic who has a higher doctoral degree - usually in the form of a habilitation. The title, ''Privatdozent'', as such does not imply a sala ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gland
In animals, a gland is a group of cells in an animal's body that synthesizes substances (such as hormones) for release into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland). Structure Development Every gland is formed by an ingrowth from an epithelial surface. This ingrowth may in the beginning possess a tubular structure, but in other instances glands may start as a solid column of cells which subsequently becomes tubulated. As growth proceeds, the column of cells may split or give off offshoots, in which case a compound gland is formed. In many glands, the number of branches is limited, in others (salivary, pancreas) a very large structure is finally formed by repeated growth and sub-division. As a rule, the branches do not unite with one another, but in one instance, the liver, this does occur when a reticulated compound gland is produced. In compound glands the more typical or secretory epithelium is found forming t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
André Marie Constant Duméril
André Marie Constant Duméril (1 January 1774 – 14 August 1860) was a French zoologist. He was professor of anatomy at the Muséum national d'histoire naturelle from 1801 to 1812, when he became professor of herpetology and ichthyology. His son Auguste Duméril was also a zoologist. Life André Marie Constant Duméril was born on 1 January 1774 in Amiens and died on 14 August 1860 in Paris. He became a doctor at a young age, obtaining, at 19 years, the ''prévot'' of anatomy at the medical school of Rouen. In 1800, he left for Paris and collaborated in the drafting of the comparative anatomy lessons of Georges Cuvier. He replaced Cuvier at the Central School of the Panthéon and had, as his colleague, Alexandre Brongniart. In 1801, he gave courses to the medical school of Paris. Under the ''Restauration'', he was elected a member of the Académie des Sciences (French Academy of Sciences) and after 1803 succeeded Lacépède, who was occupied by his political offic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Étienne Geoffroy Saint-Hilaire
Étienne Geoffroy Saint-Hilaire (15 April 177219 June 1844) was a French naturalist who established the principle of "unity of composition". He was a colleague of Jean-Baptiste Lamarck and expanded and defended Lamarck's evolutionary theories. Geoffroy's scientific views had a transcendental flavor (unlike Lamarck's materialistic views) and were similar to those of German morphologists like Lorenz Oken. He believed in the underlying unity of organismal design, and the possibility of the transmutation of species in time, amassing evidence for his claims through research in comparative anatomy, paleontology, and embryology. He is considered as a predecessor of the evo-devo evolutionary concept. Life and early career Geoffroy was born at Étampes (in present-day Essonne), and studied at the Collège de Navarre, in Paris, where he studied natural philosophy under M. J. Brisson. He then attended the lectures of Daubenton at the College de France and Fourcroy at the Jardin des Pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georges Cuvier
Jean Léopold Nicolas Frédéric, Baron Cuvier (; 23 August 1769 – 13 May 1832), known as Georges Cuvier, was a French natural history, naturalist and zoology, zoologist, sometimes referred to as the "founding father of paleontology". Cuvier was a major figure in natural sciences research in the early 19th century and was instrumental in establishing the fields of comparative anatomy and paleontology through his work in comparing living animals with fossils. Cuvier's work is considered the foundation of vertebrate paleontology, and he expanded Linnaean taxonomy by grouping classes into phylum, phyla and incorporating both fossils and living species into the classification. Cuvier is also known for establishing extinction as a fact—at the time, extinction was considered by many of Cuvier's contemporaries to be merely controversial speculation. In his ''Essay on the Theory of the Earth'' (1813) Cuvier proposed that now-extinct species had been wiped out by periodic catastrophi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
