| APRIL 1 - BIRTHS | |
| Alain Connes | |
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French mathematician who won the 1982 Fields Medal (awarded in 1983) for his work in operator theory. His most remarkable contributions are (1) general classification and a structure theorem for factors of type III, obtained in his thesis (1973); (2) classification of automorphisms of the hyperfinite factor, which served as a preparation for the next contribution; (3) classification of injective factors; and (4) application of the theory of C*-algebras to foliations and differential geometry in general. Connes' recent work has been on noncommutative geometry and he has studied applications to theoretical physics.« |
| Claude Cohen-Tannoudji | |
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French physicist who shared the Nobel Prize for Physics in 1997 (with Steven Chu and William D. Phillips) for developing methods using laser light to cool gases to the micro-kelvin temperature range (nearly absolute zero to a fraction of a millionth of a degree.) The motion of the chilled atoms is thereby sufficiently slowed to permit their study with very great accuracy, and their inner structure can be determined. Cohen-Tannoudji created laser traps that operate by a process of what has since been called Sisyphus cooling. Working with helium atoms, using six laser beams, he attained a temperature of 0.18 µK. Under these conditions helium atoms slowed to a speed of only about 2 cm/s.« |
| Norman Abramson | |
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American computer scientist who created ALOHANET, the first modern data network, which formed the basis of the protocols essential in the Ethernet now in wide use. It opened in 1970, operating at 9600 bits per second, using radio to provide a wireless packet-switched data network between several Hawaii islands. Its innovations included the first packet radio sensors, the first packet radio repeaters, the first satellite packet network and the first radio access to the Internet. Abramson's U.S. patents include the first patent for CRC redundancy checks to provide data error control technique (No. 3,114,130), and the first patent issued for the design of burst errors in digital systems (No. 3,163,848).« |
| Joseph E. Murray | |
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American surgeon who shared (with E. Donnall Thomas) the Nobel Prize for Physiology or Medicine in 1990 for discoveries concerning "organ and cell transplantation in the treatment of human disease." His work concerned how rejection following organ transplantation in man could be mastered. Murray successfully transplanted a kidney between homozygous twins for the first time. He pioneered transplantation of kidneys obtained from deceased persons and could show that patients with terminal renal insufficiency could be cured. The field was then open for transplantation of other organs such as liver, pancreas and heart.« |
| John Holter | |
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American inventor of a pioneering valve used in the treatment of hydrocephalus ("water on the brain"). Shortly after birth (1955), his son suffered from hydrocephalus. Holter learned from surgeons Eugene Spitz and Frank Nulsen that a suitable valve to drain fluid from the brain could maintain normal cranial pressure. To save his son, Holter invented a pressure-sealing valve made from silicone to avoid clogging problems. He subsequently refined and patented the device. Spitz and Holter set up a company to manufacture the shunts using Silastic silicone. The Spitz-Holter valve has helped millions around the world since the late 1950s. Holter later created other medical devices, including dialysis pumps, artificial heart valves and finger tendons.« [Image: Schematic of placement of drainage tube with valve seen placed subcutaneously beside ear.] |
| Abraham H. Maslow | |
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Abraham Harold Maslow was a U.S. psychologist who believed that man has a natural drive to healthiness, and developed this into his self-actualization theory of psychology. Thus, man knows more than his physical needs to maintain health, but also knows intuitively what he needs to become mentally healthy and happy. In his early career, working with monkeys, he observed that some needs take precedence over others, for example, thirst takes priority over hunger. Later, he created his now famous hierarchy of needs. Beyond the details of air, water, food, and sex, he laid out five broader layers: physiological needs, needs for safety and security, needs for love and belonging, needs for esteem, and the need to actualize the self, in that order.« |
| Richard Zsigmondy | |
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Austrian chemist who was awarded the Nobel Prize for Chemistry in 1925 for "his demonstration of the heterogenous nature of colloid solutions and for the methods he used, which have since become fundamental in modern colloid chemistry." Colloids are composed of submicroscopic particles dispersed within another substance. To conduct his research on colloids he invented the ultramicroscope (1903), with which he could view particles with a diameter of one 10-millionth of a millimetre not visible in a conventional microscope. It used an intense beam of light oriented in a position perpendicular to the microscope's optical axis. As particles scattered the incident light, their movements could be seen as flashes against a dark background.« |
| Sophie Germain | |
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French mathematician who is known for her work in number theory and contributions to the applied mathematics of acoustics and elasticity. Germain was self-taught from books, and from lecture notes supplied by male friends attending the Ecole Polytechnique which she, as a woman, was not permitted to attend. Using a male pseudonym, M. LeBlanc, she corresponded with Lagrange who recognised her skill, and subsequently sponsored her work. She accomplished a limited proof of Fermat's last theorem, for any prime under 100 where certain conditions were met. In 1816, she won a prize sponsored by Napoleon for a mathematical explanation of Chladni figures, the vibration of elastic plates. She died at age 55, from breast cancer.« |
| William Harvey | |
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English physician and discoverer of the true nature of the circulation of the blood and of the function of the heart as a pump. Functional knowledge of the heart and the circulation had remained almost at a standstill ever since the time of the Greco-Roman physician Galen - 1,400 years earlier. Harvey's courage, penetrating intelligence, and precise methods were to set the pattern for research in biology and other sciences for succeeding generations, so that he shares with William Gilbert, investigator of the magnet, the credit for initiating accurate experimental research throughout the world. |
| APRIL 1 - DEATHS | |
| Solly Zuckerman, Zuckerman of Burnham Thorpe | |
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(Baron) British scientist (born in South Africa). After completing medical studies in England, his first career was teaching anatomy at University College London and doing research at London Zoo on primate behaviour (1928-32). When WW II began, he became a scientific adviser for the British Defense Ministry, beginning with experimental studies of concussion (the effects that bomb blast shock waves have on the body) and became a military strategist and government adviser (1939-46; 1960-66). He remained busy after retirement, as President of the Zoological Society of London, as a campaigner against the nuclear arms race, and as a promoter of environmental research. |
| Dame Kathleen Lonsdale | |
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(née Yardley) British crystallographer who developed several X-ray techniques for the study of crystal structure. Her experimental determination of the structure of the benzene ring by x-ray diffraction, which showed that all the ring C-C bonds were of the same length and all the internal C-C-C bond angles were 120 degrees, had an enormous impact on organic chemistry. She was the first woman to be elected (1945) to the Royal Society of London. |
| Lev Davidovich Landau | |
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Soviet physicist who worked in such fields as low-temperature physics, atomic and nuclear physics, and solid-state, stellar-energy, and plasma physics. Several physics terms bear his name. He was awarded the 1962 Nobel Prize for Physics for his theory to explain the peculiar superfluid behaviour of liquid helium at very low temperature (2.18 K). Landau's further contributions are partly reflected in such terms as Landau diamagnetism and Landau levels in solid-state physics, Landau damping in plasma physics, the Landau energy spectrum in low-temperature physics, or Landau cuts in high-energy physics. |
| Charles Richard Drew | |
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African-American physician and surgeon who was an authority on the preservation of human blood for transfusion. He organized and directed the blood-plasma programs of the United States and Great Britain in the early years of World War II, while also agitating the authorities to stop excluding the blood of blacks from plasma-supply networks. His death was caused by a car accident. |
| Seaman Asahel Knapp | |
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American agriculturist who originated the method in which an expert demonstrates, farm by farm, new agricultural discoveries and technologies. He introduced improved methods of farming into Louisiana, spurred the development of rice culture in the Southwest, demonstrated methods for curbing the boll weevil in Texas, and inaugurated a federal program of farm demonstrations throughout the South. Knapp's legacy was to bring progressive agricultural methods to the American farmer. An agrarian reformer, to change the pattern of society for the benefit of mankind, he organized a system of county farm and home demonstration agents and boys and girls clubs from which developed the U.S. Cooperative Extension Service. |
| François-Marie Raoult | |
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French chemist who formulated a law on solutions (called Raoult's law) that made it possible to determine the molecular weights of dissolved substances. |
| Saint George Jackson Mivart | |
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English biologist who was a leading critic of Charles Darwin's theory of natural selection. Although called to the Bar in 1851, he instead pursued his interests in natural history and comparative anatomy, studying the insectivores and carnivores. He held that variation was predetermined by a higher intelligence, and that evolution proceeded in a step-wise fashion, and not an accumulation of small variations. In Jan 1871 he published Genesis of Species, opposing Darwin's interpretation of evolution. Mivart's liberal position even seemed to conflict with his Roman Catholic religion, for which he was excommunicated by Cardinal Vaughan in Jan 1900, a few months before he died.« |
| Hugo von Mohl | |
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German botanist noted for his research on the anatomy and physiology of plant cells. He developed the idea that the nucleus of the cell was within the granular, colloidal material that made up the main substance of the cell. In 1846 he named this substance protoplasm, a word that had been invented by the Czech physiologist Jan Evangelista Purkinje with reference to the embryonic material found in eggs. Von Mohl was also first to propose that new cells are formed by cell division, a process he observed in the alga Conferva glomerata. |
| Charles-Édouard Brown-Séquard | |
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French physiologist and neurologist, a pioneer endocrinologist and neurophysiologist who was among the first to work out the physiology of the spinal cord. In 1849, he discovered that the sensory, though not the motor, fibres in the spinal cord are crossed. Thus a cut halfway through the cord from one side produces paralysis in the same side of the body but anesthesia in the side opposite to the cut. He also studied the physiological effects of the injection of genital gland extracts. In 1856 he discovered that the adrenal gland is essential for life. He later showed that "internal secretions" (i.e., hormones) serve the body's cells as a means of communication with each other, secondary to the nervous system (1891). |
| Jakob Steiner | |
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Swiss mathematician, who was one of the greatest contributors to projective geometry. He discovered the Steiner surface which has a double infinity of conic sections on it. The Steiner theorem states that the two pencils by which a conic is projected from two of its points are projectively related. He is also known for the Poncelet-Steiner theorem which shows that only one given circle and a straight edge are required for Euclidean constructions. His work included conic sections and surfaces, the theory of second-degree surfaces and centre-of-gravity problems. He developed the principle of symmetrization (1840-41). In 1848 he ws the first to define various polar curves with respect to a given curve, and introduced the "Steiner Curves."« |
| APRIL 1 - EVENTS | |
| President Carter visits Three Mile Island | |
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| Weather satellite | |
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| Alpher, Bethe & Gamow | |
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| Death of panda Su Lin | |
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| Electric trolley car | |
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| First commercial dishwashing machine | |
(USPTO) |
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| First newspaper weather map | |
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| First steamship on U.S. stamp | |
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| Antiseptic surgery | |
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