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Louis Pasteur
Louis Pasteur (, ; 27 December 1822 – 28 September 1895) was a French chemist, pharmacist, and microbiologist renowned for his discoveries of the principles of vaccination, Fermentation, microbial fermentation, and pasteurization, the last of which was named after him. His research in chemistry led to remarkable breakthroughs in the understanding of the causes and preventions of diseases, which laid down the foundations of hygiene, public health and much of modern medicine. Pasteur's works are credited with saving millions of lives through the developments of vaccines for rabies vaccine, rabies and anthrax vaccine, anthrax. He is regarded as one of the founders of modern bacteriology and has been honored as the "father of bacteriology" and the "father of microbiology" (together with Robert Koch; the latter epithet also attributed to Antonie van Leeuwenhoek). Pasteur was responsible for disproving the doctrine of spontaneous generation. Under the auspices of the French Aca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nadar
Gaspard-Félix Tournachon (; 5 April 1820 – 20 March 1910), known by the pseudonym Nadar () or Félix Nadar'','' was a French photographer, caricaturist, journalist, novelist, balloon (aircraft), balloonist, and proponent of History of aviation#Heavier than air, heavier-than-air flight. In 1858, he became the first person to take aerial photographs. Photographic portraits by Nadar are held by many of the great national collections of photographs. His son, Paul Nadar, continued the studio after his death. Life Gaspard-Félix Tournachon (also known as Nadar) was born in early April 1820 in Paris, though some sources state he was born in Lyon. His father, Victor Tournachon, was a printer and bookseller. Nadar began to study medicine but quit for economic reasons after his father's death. Nadar started working as a caricaturist and novelist for various newspapers. He fell in with the Parisian bohemian group of Gérard de Nerval, Charles Baudelaire, and Théodore de Banville. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asimov's Biographical Encyclopedia Of Science And Technology
''Asimov's Biographical Encyclopedia of Science and Technology'' is a history of science by Isaac Asimov, written as the biographies of initially 1000 scientists and later with over 1500 entries. Organized chronologically, beginning with Imhotep (entry " ) and concluding with Stephen Hawking (entry " 510), each biographical entry is numbered, allowing for easy cross-referencing of one scientist with another. Nearly every biographical sketch contains links to other biographies. For example, the article about John Franklin Enders 195has the sentence " Alexander Fleming's 077penicillin was available thanks to the work of Howard Florey 213and Ernst Boris Chain 306 . . ." This allows one to quickly refer to the articles about Fleming, Florey, and Chain. It includes scientists in all fields including biologists, chemists, astronomers, physicists, mathematicians, geologist, and explorers. The alphabetical list of biographical entries starts with ABBE, Cleveland 38and ends with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pasteur Effect
The Pasteur effect describes how available oxygen inhibits ethanol fermentation, driving yeast to switch toward aerobic respiration for increased generation of the energy carrier adenosine triphosphate (ATP). More generally, in the medical literature, the Pasteur effect refers to how the presence of oxygen causes in a decrease in the cellular rate of glycolysis and suppression of lactate accumulation. The effect occurs in animal tissues, as well as in microorganisms belonging to the fungal kingdom. Discovery In 1857, microbiologist Louis Pasteur showed that aeration of yeasted broth causes cell growth to increase while the fermentation rate decreases, based on lowered ethanol production. Explanation Yeast fungi, being facultative anaerobes, can either produce energy through ethanol fermentation or aerobic respiration. When the O2 concentration is low, the two pyruvate molecules formed through glycolysis are each fermented into ethanol and carbon dioxide. While only 2 ATP ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pasteurization
In food processing, pasteurization (American and British English spelling differences#-ise, -ize (-isation, -ization), also pasteurisation) is a process of food preservation in which packaged foods (e.g., milk and fruit juices) are treated with mild heat, usually to less than , to eliminate pathogens and extend shelf life. Pasteurization either destroys or deactivates microorganisms and enzymes that contribute to food spoilage or the risk of disease, including vegetative bacteria, but most Endospore, bacterial spores survive the process. Pasteurization is named after the French microbiologist Louis Pasteur, whose research in the 1860s demonstrated that thermal processing would deactivate unwanted microorganisms in wine. Spoilage enzymes are also inactivated during pasteurization. Today, pasteurization is used widely in the dairy industry and other food processing industries for food preservation and food safety. By the year 1999, most liquid products were heat treated in a co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liebig–Pasteur Dispute
Liebig–Pasteur dispute is the dispute between Justus von Liebig and Louis Pasteur on the processes and causes of fermentation. Dispute overview Louis Pasteur a French chemist, supported the idea that fermentation was a biological process. Justus von Liebig, a German chemist, supported the idea that fermentation was a mechanical process. Both chemists had different methods of experimentation, and they focused on different aspects of fermentation because they had different ideas about where the fermentation began in an organism. The Liebig–Pasteur feud started in 1857 when Pasteur said that fermentation can occur in the absence of oxygen. The two were aware of the other's works, but continued working with their own theories. The two mention each other, as well as other scientists, in articles and other publications about the processes and causes of fermentation. Pasteur’s position Pasteur observed that fermentation does not require oxygen, but needs yeast, which is alive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Koch–Pasteur Rivalry
The French Louis Pasteur (1822–1895) and German Robert Koch (1843–1910) are the two greatest figures in medical microbiology and in establishing acceptance of the germ theory of disease (germ theory). In 1882, fueled by French–German enmity, national rivalry and a language barrier, the tension between Pasteur and the younger Koch erupted into an acute conflict. Pasteur had already discovered molecular chirality, investigated fermentation (biochemistry), fermentation, refuted spontaneous generation, inspired Joseph Lister, 1st Baron Lister, Lister's introduction of antisepsis to surgery, introduced pasteurization to France's wine industry, answered the silkworm diseases blighting France's silkworm industry, attenuated a ''Pasteurella'' species of bacteria to develop vaccine to chicken cholera (1879), and introduced anthrax vaccine (1881). Koch had transformed bacteriology by introducing the technique of pure culture, whereby he established the microbial cause of the disease a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinetic Resolution
In organic chemistry, kinetic resolution is a means of differentiating two enantiomers in a racemic mixture. In kinetic resolution, two enantiomers react with different reaction rates in a chemical reaction with a chiral catalyst or reagent, resulting in an enantioenriched sample of the less reactive enantiomer. As opposed to chiral resolution, kinetic resolution does not rely on different physical properties of diastereomeric products, but rather on the different chemical properties of the racemic starting materials. The enantiomeric excess (ee) of the unreacted starting material continually rises as more product is formed, reaching 100% just before full completion of the reaction. Kinetic resolution relies upon differences in reactivity between enantiomers or enantiomeric complexes. Kinetic resolution can be used for the preparation of chiral molecules in organic synthesis. Kinetic resolution reactions utilizing purely synthetic reagents and catalysts are much less commo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germ Theory Of Disease
The germ theory of disease is the currently accepted scientific theory for many diseases. It states that microorganisms known as pathogens or "germs" can cause disease. These small organisms, which are too small to be seen without magnification, invade animals, plants, and even bacteria. Their growth and reproduction within their hosts can cause disease. "Germ" refers not just to bacteria but to any type of microorganism, such as protists or fungi, or other pathogens, including parasites, viruses, prions, or viroids. Diseases caused by pathogens are called infectious diseases. Even when a pathogen is the principal cause of a disease, environmental and hereditary factors often influence the severity of the disease, and whether a potential host individual becomes infected when exposed to the pathogen. Pathogens are disease-causing agents that can pass from one individual to another, across multiple domains of life. Basic forms of germ theory were proposed by Girolamo Fracastoro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galactose
Galactose (, ''wikt:galacto-, galacto-'' + ''wikt:-ose#Suffix 2, -ose'', ), sometimes abbreviated Gal, is a monosaccharide sugar that is about as sweetness, sweet as glucose, and about 65% as sweet as sucrose. It is an aldohexose and a C-4 epimer of glucose. A galactose molecule linked with a glucose molecule forms a lactose molecule. Galactan is a polymeric form of galactose found in hemicellulose, and forming the core of the galactans, a class of natural polymeric carbohydrates. D-Galactose is also known as brain sugar since it is a component of glycoproteins (oligosaccharide-protein compounds) found in Nerve tissue, nerve tissue. Etymology The word ''galactose'' was coined by Charles Weissman in the mid-19th century and is derived from Greek language, Greek , , and the generic chemical suffix for sugars ''-ose''. The etymology is comparable to that of the word ''lactose'' in that both contain roots meaning "milk sugar". Lactose is a disaccharide of galactose plus glucose. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fermentation Theory
In biochemistry, fermentation theory refers to the historical study of models of natural fermentation processes, especially alcoholic and lactic acid fermentation. Notable contributors to the theory include Justus Von Liebig and Louis Pasteur, the latter of whom developed a purely microbial basis for the fermentation process based on his experiments. Pasteur's work on fermentation later led to his development of the germ theory of disease, which put the concept of spontaneous generation to rest. Although the fermentation process had been used extensively throughout history prior to the origin of Pasteur's prevailing theories, the underlying biological and chemical processes were not fully understood. In the contemporary, fermentation is used in the production of various alcoholic beverages, foodstuffs, and medications. Overview of fermentation Fermentation is the anaerobic metabolic process that converts sugar into acids, gases, or alcohols in oxygen starved environments. Yeast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dextran
Dextran is a complex branched glucan (polysaccharide derived from the condensation of glucose), originally derived from wine. IUPAC defines dextrans as "Branched poly-α-d-glucosides of microbial origin having glycosidic bonds predominantly C-1 → C-6". Dextran chains are of varying lengths (from 3 to 2000 kilodaltons). The polymer main chain consists of α-1,6 glycosidic linkages between glucose monomers, with branches from α-1,3 linkages. This characteristic branching distinguishes a dextran from a dextrin, which is a straight chain glucose polymer tethered by α-1,4 or α-1,6 linkages. Occurrence Dextran was discovered by Louis Pasteur as a microbial product in wine, but mass production was only possible after the development by Allene Jeanes of a process using bacteria. Dental plaque is rich in dextrans. Dextran is a complicating contaminant in the refining of sugar because it elevates the viscosity of sucrose solutions and fouls plumbing. Dextran is now produced f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chirality
Chirality () is a property of asymmetry important in several branches of science. The word ''chirality'' is derived from the Greek (''kheir''), "hand", a familiar chiral object. An object or a system is ''chiral'' if it is distinguishable from its mirror image; that is, it cannot be superposed (not to be confused with superimposed) onto it. Conversely, a mirror image of an ''achiral'' object, such as a sphere, cannot be distinguished from the object. A chiral object and its mirror image are called '' enantiomorphs'' (Greek, "opposite forms") or, when referring to molecules, ''enantiomers''. A non-chiral object is called ''achiral'' (sometimes also ''amphichiral'') and can be superposed on its mirror image. The term was first used by Lord Kelvin in 1893 in the second Robert Boyle Lecture at the Oxford University Junior Scientific Club which was published in 1894: Human hands are perhaps the most recognized example of chirality. The left hand is a non-superposable mirror ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
