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1884 In Science
The year 1884 in science and technology involved some significant events, listed below. Chemistry * October 14 – George Eastman is granted his first patents for photographic roll film in the United States. * J. H. van 't Hoff proposes the Arrhenius equation for the temperature dependence of the reaction rate constant, and therefore, rate of a chemical reaction. * Hermann Emil Fischer proposes the structure of purine, a key component in many biomolecules, which he synthesizes in 1898; he also begins work on the chemistry of glucose and related sugars. * Henry Louis Le Chatelier develops Le Chatelier's principle, which explains the response of dynamic chemical equilibria to external stresses. Mathematics * Georg Cantor introduces the Cantor function. * Gottlob Frege publishes ''Die Grundlagen der Arithmetik'' ("The Foundations of Arithmetic") presenting a theory of logicism. * Edwin Abbott Abbott (as "A Square") publishes '' Flatland: A Romance of Many Dimensions'', a mathem ...
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Gottlob Frege
Friedrich Ludwig Gottlob Frege (; ; 8 November 1848 – 26 July 1925) was a German philosopher, logician, and mathematician. He was a mathematics professor at the University of Jena, and is understood by many to be the father of analytic philosophy, concentrating on the philosophy of language, logic, and mathematics. Though he was largely ignored during his lifetime, Giuseppe Peano (1858–1932), Bertrand Russell (1872–1970), and, to some extent, Ludwig Wittgenstein (1889–1951) introduced his work to later generations of philosophers. Frege is widely considered to be the greatest logician since Aristotle, and one of the most profound philosophers of mathematics ever. His contributions include the development of modern logic in the ''Begriffsschrift'' and work in the foundations of mathematics. His book the ''Foundations of Arithmetic'' is the seminal text of the logicist project, and is cited by Michael Dummett as where to pinpoint the linguistic turn. His philosophical ...
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Robert Koch
Heinrich Hermann Robert Koch ( , ; 11 December 1843 – 27 May 1910) was a German physician and microbiologist. As the discoverer of the specific causative agents of deadly infectious diseases including tuberculosis, cholera (though the Vibrio cholerae, bacterium itself was discovered by Filippo Pacini in 1854), and anthrax, he is regarded as one of the main founders of modern bacteriology. As such he is popularly nicknamed the father of microbiology (with Louis Pasteur), and as the father of medical bacteriology. His discovery of the anthrax bacterium (''Bacillus anthracis'') in 1876 is considered as the birth of modern bacteriology. His discoveries directly provided proofs for the germ theory of diseases, and the scientific basis of public health. While working as a private physician, Koch developed many innovative techniques in microbiology. He was the first to use the oil immersion lens, Condenser (optics), condenser, and microphotography in microscopy. His invention of the ...
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Typhoid Fever
Typhoid fever, also known as typhoid, is a disease caused by '' Salmonella'' serotype Typhi bacteria. Symptoms vary from mild to severe, and usually begin six to 30 days after exposure. Often there is a gradual onset of a high fever over several days. This is commonly accompanied by weakness, abdominal pain, constipation, headaches, and mild vomiting. Some people develop a skin rash with rose colored spots. In severe cases, people may experience confusion. Without treatment, symptoms may last weeks or months. Diarrhea may be severe, but is uncommon. Other people may carry the bacterium without being affected, but they are still able to spread the disease. Typhoid fever is a type of enteric fever, along with paratyphoid fever. ''S. enterica'' Typhi is believed to infect and replicate only within humans. Typhoid is caused by the bacterium ''Salmonella enterica'' subsp. ''enterica'' serovar Typhi growing in the intestines, peyers patches, mesenteric lymph nodes, spleen, liver ...
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Salmonella Typhi
''Salmonella enterica'' subsp. ''enterica'' is a subspecies of ''Salmonella enterica'', the rod-shaped, flagellated, aerobic, Gram-negative bacterium. Many of the pathogenic serovars of the ''S. enterica'' species are in this subspecies, including that responsible for typhoid. Serovars ''S. enterica'' subsp. ''enterica'' contains a large number of serovars which can infect a broad range of vertebrate hosts. The individual members range from being highly host-adapted (only able to infect a narrow range of species) to displaying a broad host range. A number of techniques are currently used to differentiate between serotypes. These include looking for the presence or absence of antigens, phage typing, molecular fingerprinting and biotyping, where serovars are differentiated by which nutrients they are able to ferment. A possible factor in determining the host range of particular serovars is phage-mediated acquisition of a small number of genetic elements that enable infection of a pa ...
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Bacillus
''Bacillus'' (Latin "stick") is a genus of Gram-positive, rod-shaped bacteria, a member of the phylum ''Bacillota'', with 266 named species. The term is also used to describe the shape (rod) of other so-shaped bacteria; and the plural ''Bacilli'' is the name of the class of bacteria to which this genus belongs. ''Bacillus'' species can be either obligate aerobes which are dependent on oxygen, or facultative anaerobes which can survive in the absence of oxygen. Cultured ''Bacillus'' species test positive for the enzyme catalase if oxygen has been used or is present. ''Bacillus'' can reduce themselves to oval endospores and can remain in this dormant state for years. The endospore of one species from Morocco is reported to have survived being heated to 420 °C. Endospore formation is usually triggered by a lack of nutrients: the bacterium divides within its cell wall, and one side then engulfs the other. They are not true spores (i.e., not an offspring). Endospore formation ...
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Georg Theodor August Gaffky
Georg Theodor August Gaffky (17 February 1850 – 23 September 1918) was a Hanover-born bacteriologist best known for identifying bacillus salmonella typhi as the cause of typhoid disease in 1884. Early life and career Gaffky's parents were the shipping agent Georg Friedrich Wilhelm Gaffky, and Emma Schumacher. His medical studies at the Friedrich Wilhelm University in Berlin were completed in 1873 after an interruption by the Franco-Prussian War in 1870. His dissertation postulated a relationship between lead poisoning and kidney disease. He worked as an assistant at the Berlin Charité hospital and passed the state medical exams in 1875. He then worked as an army surgeon. Gaffky worked as an assistant to Robert Koch in Berlin. Under Koch's leadership, Gaffky and others developed bacteriological protocols and achieved progress in identifying causes of infectious diseases. Principal discoveries Following Karl Joseph Eberth's description of a bacillus suspected as the caus ...
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Beriberi
Thiamine deficiency is a medical condition of low levels of thiamine (Vitamin B1). A severe and chronic form is known as beriberi. The two main types in adults are wet beriberi and dry beriberi. Wet beriberi affects the cardiovascular system, resulting in a fast heart rate, shortness of breath, and leg swelling. Dry beriberi affects the nervous system, resulting in numbness of the hands and feet, confusion, trouble moving the legs, and pain. A form with loss of appetite and constipation may also occur. Another type, acute beriberi, found mostly in babies, presents with loss of appetite, vomiting, lactic acidosis, changes in heart rate, and enlargement of the heart. Risk factors include a diet of mostly white rice, alcoholism, dialysis, chronic diarrhea, and taking high doses of diuretics. In rare cases, it may be due to a genetic condition that results in difficulties absorbing thiamine found in food. Wernicke encephalopathy and Korsakoff syndrome are forms of dry beriberi. ...
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Controlled Experiment
A scientific control is an experiment or observation designed to minimize the effects of variables other than the independent variable (i.e. confounding variables). This increases the reliability of the results, often through a comparison between control measurements and the other measurements. Scientific controls are a part of the scientific method. Controlled experiments Controls eliminate alternate explanations of experimental results, especially experimental errors and experimenter bias. Many controls are specific to the type of experiment being performed, as in the molecular markers used in SDS-PAGE experiments, and may simply have the purpose of ensuring that the equipment is working properly. The selection and use of proper controls to ensure that experimental results are valid (for example, absence of confounding variables) can be very difficult. Control measurements may also be used for other purposes: for example, a measurement of a microphone's background noise i ...
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Imperial Japanese Navy
The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, when it was dissolved following Japan's surrender in World War II. The Japan Maritime Self-Defense Force (JMSDF) was formed between 1952–1954 after the dissolution of the IJN. The Imperial Japanese Navy was the third largest navy in the world by 1920, behind the Royal Navy and the United States Navy (USN). It was supported by the Imperial Japanese Navy Air Service for aircraft and airstrike operation from the fleet. It was the primary opponent of the Western Allies in the Pacific War. The origins of the Imperial Japanese Navy go back to early interactions with nations on the Asian continent, beginning in the early medieval period and reaching a peak of activity during the 16th and 17th centuries at a time of cultural exchange with European powers during the Age of Discovery. After t ...
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Takaki Kanehiro
Baron was a Japanese naval physician. Early life Born in Hyūga Province (present-day Miyazaki Prefecture) as the son of a ''samurai'' retainer to the Satsuma domain, Takaki studied Chinese medicine as a youth and served as a medic in the Boshin War. He later studied western medical science under British doctor William Willis (in Japan 1861–1881). Takaki entered the Imperial Japanese Navy as a medical officer in 1872. He was sent to Great Britain for medical studies in 1875, and interned at St Thomas's Hospital Medical School now part of King's College London in London. He returned to Japan in 1880. Work on beriberi At the time, beriberi (considered endemic to Japan) was a serious problem on warships and was affecting naval efficiency. Takaki knew that beriberi was not common among Western navies. He also noticed that Japanese naval officers, whose diet consisted of various types of vegetables and meat, rarely suffered from beriberi. On the other hand, the disease was commo ...
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Novella
A novella is a narrative prose fiction whose length is shorter than most novels, but longer than most short stories. The English word ''novella'' derives from the Italian ''novella'' meaning a short story related to true (or apparently so) facts. Definition The Italian term is a feminine of ''novello'', which means ''new'', similarly to the English word ''news''. Merriam-Webster defines a novella as "a work of fiction intermediate in length and complexity between a short story and a novel". No official definition exists regarding the number of pages or words necessary for a story to be considered a novella, a short story or a novel. The Science Fiction and Fantasy Writers Association defines a novella's word count to be between 17,500 and 40,000 words. History The novella as a literary genre began developing in the Italian literature of the early Renaissance, principally Giovanni Boccaccio, author of ''The Decameron'' (1353). ''The Decameron'' featured 100 tales (named nov ...
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