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1931 In Science
The year 1931 in science and technology involved some significant events, listed below. Astronomy * French astronomer Bernard Lyot invents the coronagraph. Chemistry * Erich Hückel proposes Hückel's rule, which explains when a planar ring molecule will have aromatic properties. * Harold Urey and associates at Columbia University demonstrate the existence of heavy water. Earth sciences * Modified Mercalli intensity scale introduced as a seismic scale for earthquakes in the United States. History of science * Het Nederlandsch Historisch Natuurwetenschappelijk Museum ("The Dutch Historical Museum of the Natural Sciences") opens in Leiden. Mathematics * January – Kurt Gödel's " On Formally Undecidable Propositions..." is published in ''Monatshefte für Mathematik''. Physics * November 26 – Harold Urey discovers deuterium by the fractional distillation of liquid hydrogen. * Ernst Ruska and Max Knoll build the first prototype electron microscope. * Paul Dirac proposes that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science
Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence for scientific reasoning is tens of thousands of years old. The earliest written records in the history of science come from Ancient Egypt and Mesopotamia in around 3000 to 1200 BCE. Their contributions to mathematics, astronomy, and medicine entered and shaped Greek natural philosophy of classical antiquity, whereby formal attempts were made to provide explanations of events in the physical world based on natural causes. After the fall of the Western Roman Empire, knowledge of Greek conceptions of the world deteriorated in Western Europe during the early centuries (400 to 1000 CE) of the Middle Ages, but was preserved in the Muslim world during the Islamic Golden Age and later by the efforts of Byzantine Greek scholars who brought Greek ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
On Formally Undecidable Propositions Of Principia Mathematica And Related Systems
"Über formal unentscheidbare Sätze der Principia Mathematica und verwandter Systeme I" ("On Formally Undecidable Propositions of Principia Mathematica and Related Systems I") is a paper in mathematical logic by Kurt Gödel. Submitted November 17, 1930, it was originally published in German in the 1931 volume of ''Monatshefte für Mathematik.'' Several English translations have appeared in print, and the paper has been included in two collections of classic mathematical logic papers. The paper contains Gödel's incompleteness theorems, now fundamental results in logic that have many implications for consistency proofs in mathematics. The paper is also known for introducing new techniques that Gödel invented to prove the incompleteness theorems. Outline and key results The main results established are Gödel's first and second incompleteness theorems, which have had an enormous impact on the field of mathematical logic. These appear as theorems VI and XI, respectively, in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The American Journal Of Pathology
''The American Journal of Pathology'' is a monthly peer-reviewed medical journal covering pathology. It is published by Elsevier on behalf of the American Society for Investigative Pathology, of which it is an official journal. The editor-in-chief is Martha B. Furie ( Stony Brook University). The journal was established in 1896 as the ''Journal of the Boston Society of Medical Sciences'' and renamed ''The Journal of Medical Research'' in 1901, before obtaining its current title in 1925. According to the ''Journal Citation Reports'', the journal has a 2020 impact factor of 4.307. Editors The following persons have been editors-in-chief An editor-in-chief (EIC), also known as lead editor or chief editor, is a publication's editorial leader who has final responsibility for its operations and policies. The highest-ranking editor of a publication may also be titled editor, managing ... of the journal: References External links * {{DEFAULTSORT:American Journal Of Pathology, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virus
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898,Dimmock p. 4 more than 9,000 virus species have been described in detail of the millions of types of viruses in the environment. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. The study of viruses is known as virology, a subspeciality of microbiology. When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent particles, or ''virions'', consisting of (i) the genetic material, i. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthomyxoviridae
''Orthomyxoviridae'' (from Greek language, Greek ὀρθός, ''orthós'' 'straight' + μύξα, ''mýxa'' 'mucus') is a family of negative-sense single-stranded RNA virus, negative-sense RNA viruses. It includes seven genus, genera: ''Influenza A virus, Alphainfluenzavirus'', ''Influenza B virus, Betainfluenzavirus'', ''Influenza C virus, Gammainfluenzavirus'', ''Influenza D virus, Deltainfluenzavirus'', ''Isavirus'', ''Thogotovirus'', and ''Quaranjavirus''. The first four genera contain viruses that cause influenza in birds (see also avian influenza) and mammals, including humans. Isaviruses infect salmon; the thogotoviruses are arboviruses, infecting vertebrates and invertebrates (such as ticks and mosquitoes). The Quaranjaviruses are also arboviruses, infecting vertebrates (birds) and invertebrates (arthropods). The four genera of Influenza virus that infect vertebrates, which are identified by antigenic differences in their nucleoprotein and matrix protein, are as follows: * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alice Miles Woodruff
Alice Miles Woodruff (November 29, 1900 – November 24, 1985), born Alice Lincoln Miles, was an American virologist. She developed a method for growing fowlpox outside of a live chicken alongside Ernest William Goodpasture. Her research greatly facilitated the rapid advancement in the study of viruses. Early life and education Alice Lincoln Miles was born in Cambridge, Massachusetts, the daughter of Arthur L. Miles and Marie Augusta Putnam Miles. Her father was a dentist. She graduated from Mount Holyoke College in 1922. She obtained a master's degree in 1924 and a PhD in 1925 from Yale University. Career Woodruff worked as a research assistant at Vanderbilt University from 1927 until 1931. While working with her husband and Goodpasture, she conducted studies in the "nature, infectivity, and purification of fowl-pox virus, and the character of the changes it induced on experimental infection of fowls," which became the forerunner in the cultivation of viruses. Woodruff was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernest William Goodpasture
Ernest William Goodpasture (October 17, 1886 – September 20, 1960) was an American pathologist and physician. Goodpasture advanced the scientific understanding of the pathogenesis of infectious diseases, parasitism, and a variety of rickettsial and viral infections. Together with colleagues at Vanderbilt University, he invented methods for growing viruses and rickettsiae in chicken embryos and fertilized chicken eggs. This enabled the development of vaccines against influenza, chicken pox, smallpox, yellow fever, typhus, Rocky mountain spotted fever, and other diseases. He also described Goodpasture syndrome.Valentini, Rudolph PPediatric Anti-GBM Disease (Goodpasture Syndrome). Accessed 8-28-2009. Education and professional career Goodpasture was born in Clarksville, Tennessee, in 1886. He received his B.A. from Vanderbilt University in 1908. In 1912, Goodpasture graduated from Johns Hopkins School of Medicine with an M.D. degree. There, under professors William H. Welch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proceedings Of The Royal Society
''Proceedings of the Royal Society'' is the main research journal of the Royal Society. The journal began in 1831 and was split into two series in 1905: * Series A: for papers in physical sciences and mathematics. * Series B: for papers in life sciences. Many landmark scientific discoveries are published in the Proceedings, making it one of the most historically significant science journals. The journal contains several articles written by the most celebrated names in science, such as Paul Dirac, Werner Heisenberg, Ernest Rutherford, Erwin Schrödinger, William Lawrence Bragg, Lord Kelvin, J.J. Thomson, James Clerk Maxwell, Dorothy Hodgkin and Stephen Hawking. In 2004, the Royal Society began ''The Journal of the Royal Society Interface'' for papers at the interface of physical sciences and life sciences. History The journal began in 1831 as a compilation of abstracts of papers in the ''Philosophical Transactions of the Royal Society'', the older Royal Society publication ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Monopole
In particle physics, a magnetic monopole is a hypothetical elementary particle that is an isolated magnet with only one magnetic pole (a north pole without a south pole or vice versa). A magnetic monopole would have a net north or south "magnetic charge". Modern interest in the concept stems from particle theories, notably the grand unified and superstring theories, which predict their existence. The known elementary particles that have electric charge are electric monopoles. Magnetism in bar magnets and electromagnets is not caused by magnetic monopoles, and indeed, there is no known experimental or observational evidence that magnetic monopoles exist. Some condensed matter systems contain effective (non-isolated) magnetic monopole quasi-particles, or contain phenomena that are mathematically analogous to magnetic monopoles. Historical background Early science and classical physics Many early scientists attributed the magnetism of lodestones to two different "magnetic fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paul Dirac
Paul Adrien Maurice Dirac (; 8 August 1902 – 20 October 1984) was an English theoretical physicist who is regarded as one of the most significant physicists of the 20th century. He was the Lucasian Professor of Mathematics at the University of Cambridge, a professor of physics at Florida State University and the University of Miami, and a 1933 Nobel Prize recipient. Dirac made fundamental contributions to the early development of both quantum mechanics and quantum electrodynamics. Among other discoveries, he formulated the Dirac equation which describes the behaviour of fermions and predicted the existence of antimatter. Dirac shared the 1933 Nobel Prize in Physics with Erwin Schrödinger "for the discovery of new productive forms of atomic theory". He also made significant contributions to the reconciliation of general relativity with quantum mechanics. Dirac was regarded by his friends and colleagues as unusual in character. In a 1926 letter to Paul Ehrenfest, Albert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Microscope
An electron microscope is a microscope that uses a beam of accelerated electrons as a source of illumination. As the wavelength of an electron can be up to 100,000 times shorter than that of visible light photons, electron microscopes have a higher resolving power than light microscopes and can reveal the structure of smaller objects. A scanning transmission electron microscope has achieved better than 50 pm resolution in annular dark-field imaging mode and magnifications of up to about 10,000,000× whereas most light microscopes are limited by diffraction to about 200 nm resolution and useful magnifications below 2000×. Electron microscopes use shaped magnetic fields to form electron optical lens systems that are analogous to the glass lenses of an optical light microscope. Electron microscopes are used to investigate the ultrastructure of a wide range of biological and inorganic specimens including microorganisms, cells, large molecules, biopsy samples, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Max Knoll
Max Knoll (17 July 1897 – 6 November 1969) was a German electrical engineer. Knoll was born in Wiesbaden and studied in Munich and at the Technical University of Berlin, where he obtained his doctorate A doctorate (from Latin ''docere'', "to teach"), doctor's degree (from Latin ''doctor'', "teacher"), or doctoral degree is an academic degree awarded by universities and some other educational institutions, derived from the ancient formalism ''l ... in the Institute for High Voltage Technology. In 1927 he became the leader of the electron research group there, where he and his co-worker, Ernst Ruska, invented the electron microscope in 1931. In April 1932, Knoll joined Telefunken in Berlin to do developmental work in the field of television design. He was also a private lecturer in Berlin. After World War II, Knoll joined the University of Munich as extraordinary professor and director of the Institute for Electromedicine. He moved to the United States, USA in 1948, to wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
