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Nathaniel Kleitman
Nathaniel Kleitman (April 26, 1895 – August 13, 1999) was an American physiologist and sleep researcher who served as Professor Emeritus in Physiology at the University of Chicago. He is recognized as the father of modern sleep research, and is the author of the seminal 1939 book ''Sleep and Wakefulness''. Biography Early life Nathaniel Kleitman was born in Chișinău, also known as Kishinev, the capital of the province of Bessarabia (now Moldova), in 1895 to a Jewish family. He was deeply interested in consciousness and reasoned that he could get insight in consciousness by studying the unconsciousness of sleep. Pogroms drove him to Palestine, and in 1915 he emigrated to the United States as a result of World War I. At the age of twenty, he landed in New York City penniless; in 1923, at age twenty-eight, he had worked his way through City College of New York and earned a PhD from the University of Chicago's Department of Physiology. His thesis was "Studies on the physiolo ...
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Chișinău
Chișinău ( , , ), also known as Kishinev (russian: Кишинёв, r=Kishinjóv ), is the capital and largest city of the Republic of Moldova. The city is Moldova's main industrial and commercial center, and is located in the middle of the country, on the river Bâc, a tributary of the Dniester. According to the results of the 2014 census, the city proper had a population of 532,513, while the population of the Municipality of Chișinău (which includes the city itself and other nearby communities) was 700,000. Chișinău is the most economically prosperous locality in Moldova and its largest transportation hub. Nearly a third of Moldova's population lives in the metro area. Etymology The origin of the city's name is unclear. A theory suggests that the name may come from the archaic Romanian word ''chișla'' (meaning "spring", "source of water") and ''nouă'' ("new"), because it was built around a small spring, at the corner of Pușkin and Albișoara streets. The other v ...
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World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fighting occurring throughout Europe, the Middle East, Africa, the Pacific, and parts of Asia. An estimated 9 million soldiers were killed in combat, plus another 23 million wounded, while 5 million civilians died as a result of military action, hunger, and disease. Millions more died in genocides within the Ottoman Empire and in the 1918 influenza pandemic, which was exacerbated by the movement of combatants during the war. Prior to 1914, the European great powers were divided between the Triple Entente (comprising France, Russia, and Britain) and the Triple Alliance (containing Germany, Austria-Hungary, and Italy). Tensions in the Balkans came to a head on 28 June 1914, following the assassination of Archduke Franz Ferdi ...
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World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. World War II was a total war that directly involved more than 100 million personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the only two nuclear weapons ever used in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, mostly among civilians. Tens of millions died due to genocides (including the Holocaust), starvation, massa ...
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Kentucky
Kentucky ( , ), officially the Commonwealth of Kentucky, is a state in the Southeastern region of the United States and one of the states of the Upper South. It borders Illinois, Indiana, and Ohio to the north; West Virginia and Virginia to the east; Tennessee to the south; and Missouri to the west. Its northern border is defined by the Ohio River. Its capital is Frankfort, and its two largest cities are Louisville and Lexington. Its population was approximately 4.5 million in 2020. Kentucky was admitted into the Union as the 15th state on June 1, 1792, splitting from Virginia in the process. It is known as the "Bluegrass State", a nickname based on Kentucky bluegrass, a species of green grass found in many of its pastures, which has supported the thoroughbred horse industry in the center of the state. Historically, it was known for excellent farming conditions for this reason and the development of large tobacco plantations akin to those in Virginia and North Carolin ...
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Mammoth Cave National Park
Mammoth Cave National Park is an American national park in west-central Kentucky, encompassing portions of Mammoth Cave, the longest cave system known in the world. Since the 1972 unification of Mammoth Cave with the even-longer system under Flint Ridge to the north, the official name of the system has been the Mammoth–Flint Ridge Cave System. The park was established as a national park on July 1, 1941, a World Heritage Site on October 27, 1981, an international Biosphere Reserve on September 26, 1990 and an International Dark Sky Park on October 28, 2021. The park's are located primarily in Edmonson County, with small areas extending eastward into Hart and Barren counties. The Green River runs through the park, with a tributary called the Nolin River feeding into the Green just inside the park. Mammoth Cave is the world's longest known cave system with more than of surveyed passageways, which is nearly twice as long as the second-longest cave system, Mexico' ...
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Basic Rest Activity Cycle
BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College in 1963. They wanted to enable students in non-scientific fields to use computers. At the time, nearly all computers required writing custom software, which only scientists and mathematicians tended to learn. In addition to the program language, Kemeny and Kurtz developed the Dartmouth Time Sharing System (DTSS), which allowed multiple users to edit and run BASIC programs simultaneously on remote terminals. This general model became very popular on minicomputer systems like the PDP-11 and Data General Nova in the late 1960s and early 1970s. Hewlett-Packard produced an entire computer line for this method of operation, introducing the HP2000 series in the late 1960s and continuing sales into the 1980s. Many early video games trace their ...
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Ultradian Rhythm
In chronobiology, an ultradian rhythm is a recurrent period or cycle repeated throughout a 24-hour day. In contrast, circadian rhythms complete one cycle daily, while infradian rhythms such as the human menstrual cycle have periods longer than a day. The ''Oxford English Dictionary's'' definition of ''Ultradian'' specifies that it refers to cycles with a period shorter than a day but longer than an hour. The descriptive term ultradian is used in sleep research in reference to the 90–120 minute cycling of the sleep stages during human sleep. There is a circasemidian rhythm in body temperature and cognitive function which is technically ultradian. However, this appears to be the first harmonic of the circadian rhythm of each and not an endogenous rhythm with its own rhythm generator. Other ultradian rhythms include blood circulation, blinking, pulse, hormonal secretions such as growth hormone, heart rate, thermoregulation, micturition, bowel activity, nostril dilation, ap ...
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Circadian Rhythm
A circadian rhythm (), or circadian cycle, is a natural, internal process that regulates the sleep–wake cycle and repeats roughly every 24 hours. It can refer to any process that originates within an organism (i.e., endogenous) and responds to the environment ( entrained by the environment). These 24-hour rhythms are driven by a circadian clock, and they have been widely observed in animals, plants, fungi and cyanobacteria. The term ''circadian'' comes from the Latin ''circa'', meaning "approximately", and ''dies'', meaning "day". Processes with 24-hour cycles are more generally called diurnal rhythms; diurnal rhythms should not be called circadian rhythms unless they can be confirmed as endogenous, and not environmental. Although circadian rhythms are endogenous, they are adjusted to the local environment by external cues called zeitgebers (German for "time givers"), which include light, temperature and redox cycles. In clinical settings, an abnormal circadian rhythm in h ...
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Stanford University School Of Medicine
Stanford University School of Medicine is the medical school of Stanford University and is located in Stanford, California. It traces its roots to the Medical Department of the University of the Pacific, founded in San Francisco in 1858. This medical institution, then called Cooper Medical College, was acquired by Stanford in 1908. The medical school moved to the Stanford campus near Palo Alto, California, in 1959. The School of Medicine, along with Stanford Health Care and Lucile Packard Children's Hospital, is part of Stanford Medicine. Stanford Health Care was ranked the fourth best hospital in California (behind UCLA Medical Center, Cedars-Sinai Medical Center, and UCSF Medical Center, respectively). History In 1855, Illinois physician Elias Samuel Cooper moved to San Francisco in the wake of the California Gold Rush. In cooperation with the University of the Pacific (also known as California Wesleyan College), Cooper established the Medical Department of the Univers ...
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William C
William is a male given name of Germanic origin.Hanks, Hardcastle and Hodges, ''Oxford Dictionary of First Names'', Oxford University Press, 2nd edition, , p. 276. It became very popular in the English language after the Norman conquest of England in 1066,All Things William"Meaning & Origin of the Name"/ref> and remained so throughout the Middle Ages and into the modern era. It is sometimes abbreviated "Wm." Shortened familiar versions in English include Will, Wills, Willy, Willie, Bill, and Billy. A common Irish form is Liam. Scottish diminutives include Wull, Willie or Wullie (as in Oor Wullie or the play ''Douglas''). Female forms are Willa, Willemina, Wilma and Wilhelmina. Etymology William is related to the given name ''Wilhelm'' (cf. Proto-Germanic ᚹᛁᛚᛃᚨᚺᛖᛚᛗᚨᛉ, ''*Wiljahelmaz'' > German ''Wilhelm'' and Old Norse ᚢᛁᛚᛋᛅᚼᛅᛚᛘᛅᛋ, ''Vilhjálmr''). By regular sound changes, the native, inherited English form of th ...
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Electroencephalography
Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The biosignals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex and allocortex. It is typically non-invasive, with the EEG electrodes placed along the scalp (commonly called "scalp EEG") using the International 10-20 system, or variations of it. Electrocorticography, involving surgical placement of electrodes, is sometimes called "intracranial EEG". Clinical interpretation of EEG recordings is most often performed by visual inspection of the tracing or quantitative EEG analysis. Voltage fluctuations measured by the EEG bioamplifier and electrodes allow the evaluation of normal brain activity. As the electrical activity monitored by EEG originates in neurons in the underlying brain tissue, the recordings made by the electrodes on the surface of the scalp vary in accordance with their orientation ...
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Eugene Aserinsky
Eugene Aserinsky (May 6, 1921 – July 22, 1998), a pioneer in sleep research, was a graduate student at the University of Chicago in 1953 when he discovered REM sleep. He was the son of a dentist of Russian–Jewish descent. He made the discovery after hours spent studying the eyelids of sleeping subjects. While the phenomenon was in the beginning more interesting for a fellow of PhD student Aserinsky, William Charles Dement, both Aserinsky and their PhD adviser, Nathaniel Kleitman, went on to demonstrate that this "rapid-eye movement" was correlated with dreaming and a general increase in brain activity. Aserinsky and Kleitman pioneered procedures that have now been used with thousands of volunteers using the electroencephalograph. Because of these discoveries, Aserinsky and Kleitman are generally considered the founders of modern sleep research. Eugene Aserinsky died on July 22, 1998, when his car hit a tree north of San Diego. An autopsy was inconclusive about the cau ...
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