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1872 In Science
The year 1872 in science and technology involved some significant events, listed below. Chemistry * Robert Chesebrough patents Vaseline in the United States * Eugen Baumann rediscovers polyvinyl chloride * Charles-Adolphe Wurtz discovers the aldol reaction Conservation * March 1 – Yellowstone National Park is established in the United States, the world's first national park Exploration * December 21 – ''Challenger'' expedition: sails from Portsmouth in England on the 4-year scientific expedition that lays the foundation for the science of oceanography Mathematics * Richard Dedekind publishes ''Stetigkeit und irrationale Zahlen'', a theory of irrational numbers * Felix Klein produces the Erlangen program on geometries Medicine * February 15 – George Huntington makes the first detailed description of Huntington's disease, in Middleport, Ohio * Moritz Kaposi describes Kaposi's sarcoma and the manifestations of systemic lupus erythematosus * Ferdinand Monoyer propo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richard Dedekind
Julius Wilhelm Richard Dedekind (; ; 6 October 1831 – 12 February 1916) was a German mathematician who made important contributions to number theory, abstract algebra (particularly ring theory), and the axiomatic foundations of arithmetic. His best known contribution is the definition of real numbers through the notion of Dedekind cut. He is also considered a pioneer in the development of modern set theory and of the philosophy of mathematics known as ''logicism''. Life Dedekind's father was Julius Levin Ulrich Dedekind, an administrator of Collegium Carolinum in Braunschweig. His mother was Caroline Henriette Dedekind (née Emperius), the daughter of a professor at the Collegium. Richard Dedekind had three older siblings. As an adult, he never used the names Julius Wilhelm. He was born in Braunschweig (often called "Brunswick" in English), which is where he lived most of his life and died. His body rests at Braunschweig Main Cemetery. He first attended the Collegium Carol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Power
In optics, optical power (also referred to as dioptric power, refractive power, focal power, focusing power, or convergence power) is the degree to which a lens, mirror, or other optical system converges or diverges light. It is equal to the reciprocal of the focal length of the device; high optical power corresponds to short focal length. The SI unit for optical power is the inverse metre (), which is also called a '' dioptre'' (symbol: dpt or D) when used as a unit of optical power. Explanation The optical power of a device is related to its focal length by . Converging lenses have positive optical power, while diverging lenses have negative power. When a lens is immersed in a refractive medium, its optical power and focal length change. For two or more thin lenses close together, the optical power of the combined lenses is approximately equal to the sum of the optical powers of each lens: . Similarly, the optical power of a single lens is roughly equal to the sum o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dioptre
A dioptre ( British spelling) or (American spelling), symbol dpt or D, is a unit of measurement with dimension of reciprocal length, equivalent to one reciprocal metre, . It is normally used to express the optical power of a lens or curved mirror, which is a physical quantity equal to the reciprocal of the focal length, expressed in metres. For example, a 3-dioptre lens brings parallel rays of light to focus at metre. A flat window has an optical power of zero dioptres, as it does not cause light to converge or diverge. Dioptres are also sometimes used for other reciprocals of distance, particularly radii of curvature and the vergence of optical beams. The main benefit of using optical power rather than focal length is that the thin lens formula has the object distance, image distance, and focal length all as reciprocals. Additionally, when relatively thin lenses are placed close together their powers approximately add. Thus, a thin 2.0-dioptre lens placed close to a th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systemic Lupus Erythematosus
Lupus, formally called systemic lupus erythematosus (SLE), is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body. Symptoms vary among people and may be mild to severe. Common symptoms include painful and swollen joints, fever, chest pain, hair loss, mouth ulcers, swollen lymph nodes, feeling tired, and a red rash which is most commonly on the face. Often there are periods of illness, called flares, and periods of remission during which there are few symptoms. Children up to 18 years old develop a more severe form of SLE termed childhood-onset systemic lupus erythematosus. The cause of SLE is not clear. It is thought to involve a combination of genetics and environmental factors. Among identical twins, if one is affected there is a 24% chance the other one will also develop the disease. Female sex hormones, sunlight, smoking, vitamin D deficiency, and certain infections are also believed to increa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Who Named It?
''Whonamedit?'' is an online English-language dictionary of medical eponyms and the people associated with their identification. Though it is a dictionary, many eponyms and persons are presented in extensive articles with comprehensive bibliographies. The dictionary is hosted in Norway Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. The remote Arctic island of Jan Mayen and the archipelago of Svalbard also form part of the Kingdom of ... and was developed by medical historian Ole Daniel Enersen. References External links * Medical websites Medical dictionaries Eponyms in medicine {{online-dict-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kaposi's Sarcoma
Kaposi's sarcoma (KS) is a type of cancer that can form masses on the skin, in lymph nodes, in the mouth, or in other organs. The skin lesions are usually painless, purple and may be flat or raised. Lesions can occur singly, multiply in a limited area, or may be widespread. Depending on the sub-type of disease and level of immune suppression, KS may worsen either gradually or quickly. Except for classic KS where there is generally no immune suppression, KS is caused by a combination of Immunosuppression, immune suppression (such as due to HIV/AIDS) and infection by Human herpesvirus 8 (HHV8 – also called KS-associated herpesvirus (KSHV)). Classic, endemic, immunosuppression therapy-related (also known as iatrogenic), and epidemic (also known as AIDS-related) sub-types are all described. Classic KS tends to affect older men in regions where KSHV is highly prevalent (Mediterranean, Eastern Europe, Middle East), is usually slow-growing, and most often affects only the legs. Endem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moritz Kaposi
Moritz Kaposi (, ; 23 October 1837 – 6 March 1902) was a physician and dermatologist from the Austro-Hungarian Empire who discovered the skin tumor that received his name (Kaposi's sarcoma). Biography Early life and name Born in Kaposvár, Hungary, Austrian Empire, to a Jewish family, originally his surname was Kohn; but, with his conversion to the Catholic faith, he changed it to Kaposi in 1871, in reference to his town of birth. One purported reason behind this is that he wanted to marry a daughter of current dermatology chairman, Ferdinand Ritter von Hebra, and advance in the society, which he could not have done being of Jewish faith. This seems unlikely because he married Martha Hebra and converted to Catholicism several years prior to changing his name, by which time he was already well established in the Vienna University faculty and a close associate of her father, Ferdinand. A more plausible explanation is based on his own comments to colleagues that he changed his ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of The History Of The Neurosciences
''Journal of the History of the Neurosciences'' is a British academic journal founded in 1992. It covers the history of neuroscience Neuroscience is the scientific study of the nervous system (the brain, spinal cord, and peripheral nervous system), its functions, and its disorders. It is a multidisciplinary science that combines physiology, anatomy, molecular biology, .... The journal contains a combination of original articles, book reviews, and two unique types of columns called "NEUROwords" and the "Neurognostics" Questions and Answers. References International Society for the History of the Neurosciences External links International Society for the History of the Neurosciences Academic journals established in 1992 History of medicine journals Neurology journals Neuroscience journals Neuroscience in the United Kingdom Quarterly journals {{med-hist-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Huntington's Disease
Huntington's disease (HD), also known as Huntington's chorea, is an incurable neurodegenerative disease that is mostly Genetic disorder#Autosomal dominant, inherited. It typically presents as a triad of progressive psychiatric, cognitive, and motor symptoms. The earliest symptoms are often subtle problems with mood or mental/psychiatric abilities, which precede the motor symptoms for many people. The definitive physical symptoms, including a general Ataxia, lack of coordination and an unsteady human gait, gait, eventually follow. Over time, the basal ganglia region of the brain gradually Basal ganglia disease#Huntington's disease, becomes damaged. The disease is primarily characterized by a distinctive hyperkinesia, hyperkinetic movement disorder known as ''chorea.'' Chorea classically presents as uncoordinated, involuntary, "dance-like" body movements that become more apparent as the disease advances. Physical abilities gradually worsen until Motor coordination, coordinated mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Huntington
George Huntington (April 9, 1850 – March 3, 1916) was an American physician who contributed a classic clinical description of the disease that bears his name—Huntington's disease. Huntington described this condition in the first of only two scientific papers he ever wrote. He wrote this paper when he was 22, a year after receiving his medical degree from Columbia University in New York. He first read the paper before the Meigs and Mason Academy of Medicine in Middleport, Ohio on February 15, 1872, and then published it in the ''Medical and Surgical Reporter'' of Philadelphia on April 13, 1872. Huntington's father and grandfather, George Lee Huntington (1811–1881) and Abel Huntington (1778–1858), were also physicians in the same family practice. Their longitudinal observations combined with his own were invaluable in precisely describing this hereditary disease in multiple generations of a family in East Hampton on Long Island. In a 1908 review, the eminent physician ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geometry
Geometry (; ) is a branch of mathematics concerned with properties of space such as the distance, shape, size, and relative position of figures. Geometry is, along with arithmetic, one of the oldest branches of mathematics. A mathematician who works in the field of geometry is called a ''List of geometers, geometer''. Until the 19th century, geometry was almost exclusively devoted to Euclidean geometry, which includes the notions of point (geometry), point, line (geometry), line, plane (geometry), plane, distance, angle, surface (mathematics), surface, and curve, as fundamental concepts. Originally developed to model the physical world, geometry has applications in almost all sciences, and also in art, architecture, and other activities that are related to graphics. Geometry also has applications in areas of mathematics that are apparently unrelated. For example, methods of algebraic geometry are fundamental in Wiles's proof of Fermat's Last Theorem, Wiles's proof of Fermat's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
