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1945 In Science
The year 1945 in science and technology involved some significant events, listed below. Biology * Salvador Edward Luria and Alfred Day Hershey independently recognize that viruses undergo mutations. Chemistry * A team at Oak Ridge National Laboratory led by Charles DuBois Coryell, Charles Coryell discovers chemical element 61, the only one still missing between 1 and 96 on the periodic table, which they will name promethium. Found by analysis of fission products of irradiated uranium fuel, its discovery is not made public until 1947. * Dorothy Hodgkin and C. H. (Harry) Carlisle publish the first three-dimensional molecular structure of a steroid, cholesteryl iodide. In January, Hodgkin also discovers the structure of penicillin, not published until 1949 in science, 1949. * A team at American Cyanamid's Lederle Laboratories, Pearl River, New York, led by Yellapragada Subbarow, obtain folic acid in a pure crystalline form. Computer science * June 30 – Distribution of John von N ... [...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] |
1949 In Science
The year 1949 in science and technology involved some significant events, listed below. Astronomy and space exploration * June 14 – Albert II, a rhesus monkey, becomes the first mammal in space, in a U.S.-launched V-2 rocket, reaching an altitude of 83 miles (134 km) but dying on impact after a parachute failure. Chemistry * Radiocarbon dating technique discovered by Willard Libby and his colleagues at the University of Chicago—work for which Libby will receive the Nobel prize in 1960. * A group including Dorothy Hodgkin publish the three-dimensional molecular structure of penicillin, demonstrating that it contains a β-lactam ring. Computer science * April – Manchester Mark 1 computer operable at the University of Manchester in England. * May 6 – EDSAC, the first practicable stored-program computer, runs its first program at University of Cambridge in England, to calculate a table of squares. Earth sciences * August 5 – Ambato earthquake in Ecuador, measuring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proto-hypertext
Hypertext is text displayed on a computer or other electronic device with references (hyperlinks) to other text that the reader can immediately access, usually by a mouse click or keypress sequence. Early conceptions of hypertext defined it as text that could be connected by a linking system to a range of other documents that were stored outside that text. In 1934 Belgian bibliographer, Paul Otlet, developed a blueprint for links that telescoped out from hypertext electrically to allow readers to access documents, books, photographs, and so on, stored anywhere in the world. History Recorders of information have long looked for ways to categorize and compile it. There are various methods of arranging layers of references/annotations within a document. Other reference works (for example dictionaries, encyclopaedias) also developed a precursor to hypertext: the setting of certain words in small capital letters, indicating that an entry existed for that term within the same refer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
As We May Think
"As We May Think" is a 1945 essay by Vannevar Bush which has been described as visionary and influential, anticipating many aspects of information society. It was first published in ''The Atlantic'' in July 1945 and republished in an abridged version in September 1945—before and after the atomic bombings of Hiroshima and Nagasaki. Bush expresses his concern for the direction of scientific efforts toward destruction, rather than understanding, and explicates a desire for a sort of collective memory machine with his concept of the memex that would make knowledge more accessible, believing that it would help fix these problems. Through this machine, Bush hoped to transform an information explosion into a knowledge explosion. Concept creation The article was a reworked and expanded version of Bush's essay "Mechanization and the Record" (1939). Here, he described a machine that would combine lower level technologies to achieve a higher level of organized knowledge (like human m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vannevar Bush
Vannevar Bush ( ; March 11, 1890 – June 28, 1974) was an American engineer, inventor and science administrator, who during World War II headed the U.S. Office of Scientific Research and Development (OSRD), through which almost all wartime military R&D was carried out, including important developments in radar and the initiation and early administration of the Manhattan Project. He emphasized the importance of scientific research to national security and economic well-being, and was chiefly responsible for the movement that led to the creation of the National Science Foundation. Bush joined the Department of Electrical Engineering at Massachusetts Institute of Technology (MIT) in 1919, and founded the company that became the Raytheon Company in 1922. Bush became vice president of MIT and dean of the MIT School of Engineering in 1932, and president of the Carnegie Institution of Washington in 1938. During his career, Bush patented a string of his own inventions. He is known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Von Neumann Architecture
The von Neumann architecture — also known as the von Neumann model or Princeton architecture — is a computer architecture based on a 1945 description by John von Neumann, and by others, in the ''First Draft of a Report on the EDVAC''. The document describes a design architecture for an electronic digital computer with these components: * A processing unit with both an arithmetic logic unit and processor registers * A control unit that includes an instruction register and a program counter * Memory that stores data and instructions * External mass storage * Input and output mechanisms.. The term "von Neumann architecture" has evolved to refer to any stored-program computer in which an instruction fetch and a data operation cannot occur at the same time (since they share a common bus). This is referred to as the von Neumann bottleneck, which often limits the performance of the corresponding system. The design of a von Neumann architecture machine is simpler than in a Harva ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stored-program Computer
A stored-program computer is a computer that stores program instructions in electronically or optically accessible memory. This contrasts with systems that stored the program instructions with plugboards or similar mechanisms. The definition is often extended with the requirement that the treatment of programs and data in memory be interchangeable or uniform. Description In principle, stored-program computers have been designed with various architectural characteristics. A computer with a von Neumann architecture stores program data and instruction data in the same memory, while a computer with a Harvard architecture has separate memories for storing program and data. However, the term ''stored-program computer'' is sometimes used as a synonym for the von Neumann architecture. Jack Copeland considers that it is "historically inappropriate, to refer to electronic stored-program digital computers as 'von Neumann machines'". Hennessy and Patterson wrote that the early Harvard m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
First Draft Of A Report On The EDVAC
The ''First Draft of a Report on the EDVAC'' (commonly shortened to ''First Draft'') is an incomplete 101-page document written by John von Neumann and distributed on June 30, 1945 by Herman Goldstine, security officer on the classified ENIAC project. It contains the first published description of the logical design of a computer using the stored-program concept, which has controversially come to be known as the von Neumann architecture. History Von Neumann wrote the report by hand while commuting by train to Los Alamos, New Mexico and mailed the handwritten notes back to Philadelphia. Goldstine had the report typed and duplicated. While the date on the typed report is June 30, 24 copies of the ''First Draft'' were distributed to persons closely connected with the EDVAC project five days earlier on June 25. Interest in the report caused it to be sent all over the world; Maurice Wilkes of Cambridge University cited his excitement over the report's content as the impetus for h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Von Neumann
John von Neumann (; hu, Neumann János Lajos, ; December 28, 1903 – February 8, 1957) was a Hungarian-American mathematician, physicist, computer scientist, engineer and polymath. He was regarded as having perhaps the widest coverage of any mathematician of his time and was said to have been "the last representative of the great mathematicians who were equally at home in both pure and applied mathematics". He integrated pure and applied sciences. Von Neumann made major contributions to many fields, including mathematics (foundations of mathematics, measure theory, functional analysis, ergodic theory, group theory, lattice theory, representation theory, operator algebras, matrix theory, geometry, and numerical analysis), physics (quantum mechanics, hydrodynamics, ballistics, nuclear physics and quantum statistical mechanics), economics ( game theory and general equilibrium theory), computing ( Von Neumann architecture, linear programming, numerical meteo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Journal Of Haematology
The ''British Journal of Haematology'' is a peer-reviewed medical journal focusing on hematology and other blood-related topics, such as blood diseases and their treatment. It is published by ileyon behalf of the British Society for Haematology. Indexing According to the ''Journal Citation Reports'', the ''British Journal of Haematology'' had a 2016 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 5.67, ranking it 10th out of 70 in the category "Hematology". In addition, the journal is indexed in: External links ''British Journal of Haematology'' website References {{reflist Wiley-Blackwell academic journals Publications established in 1955 English-language journals Hematology journals Academic journals associated with learned and professional societ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science (journal)
''Science'', also widely referred to as ''Science Magazine'', is the peer-reviewed academic journal of the American Association for the Advancement of Science (AAAS) and one of the world's top academic journals. It was first published in 1880, is currently circulated weekly and has a subscriber base of around 130,000. Because institutional subscriptions and online access serve a larger audience, its estimated readership is over 400,000 people. ''Science'' is based in Washington, D.C., United States, with a second office in Cambridge, UK. Contents The major focus of the journal is publishing important original scientific research and research reviews, but ''Science'' also publishes science-related news, opinions on science policy and other matters of interest to scientists and others who are concerned with the wide implications of science and technology. Unlike most scientific journals, which focus on a specific field, ''Science'' and its rival ''Nature (journal), Nature'' c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Folic Acid
Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and storage. Folate is required for the body to make DNA and RNA and metabolise amino acids necessary for cell division. As humans cannot make folate, it is required in the diet, making it an essential nutrient. It occurs naturally in many foods. The recommended adult daily intake of folate in the U.S. is 400 micrograms from foods or dietary supplements. Folate in the form of folic acid is used to treat anemia caused by folate deficiency. Folic acid is also used as a supplement by women during pregnancy to reduce the risk of neural tube defects (NTDs) in the baby. Low levels in early pregnancy are believed to be the cause of more than half of babies born with NTDs. More than 80 countries use either mandatory or voluntary fortification of c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
