Twin Studies
Twin studies are studies conducted on identical or fraternal twins. They aim to reveal the importance of environmental and genetic influences for traits, phenotypes, and disorders. Twin research is considered a key tool in behavioral genetics and in related fields, from biology to psychology. Twin studies are part of the broader methodology used in behavior genetics, which uses all data that are genetically informative – siblings studies, adoption studies, pedigree, etc. These studies have been used to track traits ranging from personal behavior to the presentation of severe mental illnesses such as schizophrenia. Twins are a valuable source for observation because they allow the study of environmental influence and varying genetic makeup: "identical" or monozygotic (MZ) twins share essentially 100% of their genes, which means that most differences between the twins (such as height, susceptibility to boredom, intelligence, depression, etc.) are due to experiences that one tw ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Identical Twin
Twins are two offspring produced by the same pregnancy.MedicineNet > Definition of TwinLast Editorial Review: 19 June 2000 Twins can be either ''monozygotic'' ('identical'), meaning that they develop from one zygote, which splits and forms two embryos, or ''dizygotic'' ('non-identical' or 'fraternal'), meaning that each twin develops from a separate egg and each egg is fertilized by its own sperm cell. Since identical twins develop from one zygote, they will share the same sex, while fraternal twins may or may not. In rare cases twins can have the same mother and different fathers (heteropaternal superfecundation). In contrast, a fetus that develops alone in the uterus, womb (the much more common case, in humans) is called a ''singleton'', and the general term for one offspring of a multiple birth is a ''multiple''. Unrelated look-alikes whose resemblance parallels that of twins are referred to as doppelgängers. Statistics The human twin birth rate in the United States rose 7 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Heritability Of Autism
The heritability of autism is the proportion of differences in expression of autism that can be explained by genetic variation; if the heritability of a condition is high, then the condition is considered to be primarily genetic. Autism has a strong genetic basis, although the genetics of autism are complex and it is unclear whether autism spectrum disorder (ASD) is explained more by multigene interactions or by rare mutations with major effects. Early studies of twins estimated the heritability of autism to be more than 90%; in other words, that 90% of the differences between autistic and non-autistic individuals are due to genetic effects. This however may be an overestimate: new twin data and models with structural genetic variation are needed. When only one identical twin is autistic, the other often has learning or social disabilities. For adult siblings, the likelihood of having one or more features of the broader autism phenotype might be as high as 30%, much higher than t ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Galton
Sir Francis Galton, FRS FRAI (; 16 February 1822 – 17 January 1911), was an English Victorian era polymath: a statistician, sociologist, psychologist, anthropologist, tropical explorer, geographer, inventor, meteorologist, proto-geneticist, psychometrician and a proponent of social Darwinism, eugenics, and scientific racism. He was knighted in 1909. Galton produced over 340 papers and books. He also created the statistical concept of correlation and widely promoted regression toward the mean. He was the first to apply statistical methods to the study of human differences and inheritance of intelligence, and introduced the use of questionnaires and surveys for collecting data on human communities, which he needed for genealogical and biographical works and for his anthropometric studies. He was a pioneer of eugenics, coining the term itself in 1883, and also coined the phrase "nature versus nurture". His book ''Hereditary Genius'' (1869) was the first social scientific ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Clinical Trial
Clinical trials are prospective biomedical or behavioral research studies on human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, dietary choices, dietary supplements, and medical devices) and known interventions that warrant further study and comparison. Clinical trials generate data on dosage, safety and efficacy. They are conducted only after they have received health authority/ethics committee approval in the country where approval of the therapy is sought. These authorities are responsible for vetting the risk/benefit ratio of the trial—their approval does not mean the therapy is 'safe' or effective, only that the trial may be conducted. Depending on product type and development stage, investigators initially enroll volunteers or patients into small pilot studies, and subsequently conduct progressively larger scale comparative studies. Clinical trials can vary i ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Caffeine
Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class. It is mainly used recreationally as a cognitive enhancer, increasing alertness and attentional performance. Caffeine acts by blocking binding of adenosine to the adenosine A1 receptor, which enhances release of the neurotransmitter acetylcholine. Caffeine has a three-dimensional structure similar to that of adenosine, which allows it to bind and block its receptors. Caffeine also increases cyclic AMP levels through nonselective inhibition of phosphodiesterase. Caffeine is a bitter, white crystalline purine, a methylxanthine alkaloid, and is chemically related to the adenine and guanine bases of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). It is found in the seeds, fruits, nuts, or leaves of a number of plants native to Africa, East Asia and South America, and helps to protect them against herbivores and from competition by preventing the germination of nearby seeds, as well as ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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French People
The French people (french: Français) are an ethnic group and nation primarily located in Western Europe that share a common French culture, history, and language, identified with the country of France. The French people, especially the native speakers of langues d'oïl from northern and central France, are primarily the descendants of Gauls (including the Belgae) and Romans (or Gallo-Romans, western European Celtic and Italic peoples), as well as Germanic peoples such as the Franks, the Visigoths, the Suebi and the Burgundians who settled in Gaul from east of the Rhine after the fall of the Roman Empire, as well as various later waves of lower-level irregular migration that have continued to the present day. The Norse also settled in Normandy in the 10th century and contributed significantly to the ancestry of the Normans. Furthermore, regional ethnic minorities also exist within France that have distinct lineages, languages and cultures such as Bretons in Brittany, Occi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Coffee
Coffee is a drink prepared from roasted coffee beans. Darkly colored, bitter, and slightly acidic, coffee has a stimulant, stimulating effect on humans, primarily due to its caffeine content. It is the most popular hot drink in the world. Seeds of the ''Coffea'' plant's fruits are separated to produce unroasted green coffee beans. The beans are Coffee roasting, roasted and then ground into fine particles that are typically steeped in hot water before being filtered out, producing a cup of coffee. It is usually served hot, although chilled or iced coffee is common. Coffee can be prepared and presented in a variety of ways (e.g., espresso, French press, caffè latte, or already-brewed canned coffee). Sugar, sugar substitutes, milk, and cream are often used to mask the bitter taste or enhance the flavor. Though coffee is now a global commodity, it has a History of coffee, long history tied closely to food traditions around the Red Sea. The earliest credible evidence of coffee d ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Adolf Frederick Of Sweden
Adolf Frederick, or Adolph Frederick ( sv, Adolf Fredrik, german: Adolf Friedrich; 14 May 171012 February 1771) was King of Sweden from 1751 until his death. He was the son of Christian August of Holstein-Gottorp, Prince of Eutin, and Albertina Frederica of Baden-Durlach. He was an uncle of Catherine the Great The first king from the House of Holstein-Gottorp, Adolf Frederick was a weak monarch, installed as first in line to the throne following the parliamentary government's failure to reconquer the Baltic provinces in 1741–43. Aside from a few attempts, supported by pro- absolutist factions among the nobility, to reclaim the absolute monarchy held by previous monarchs, he remained a mere constitutional figurehead until his death. His reign saw an extended period of internal peace. However, the finances stagnated following failed mercantilist doctrines pursued by the Hat administration. The Hat administration ended during the 1765–66 parliament, where the Cap opposition t ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Gustav III Of Sweden's Coffee Experiment
Gustav III of Sweden's coffee experiment was a purported twin study ordered by the king to study the health effects of coffee. The authenticity of the event has been questioned. The primitive medical study, supposedly conducted in the second half of the 18th century, failed to prove that coffee was a dangerous beverage. Background In Sweden coffee was banned by royal decree across three different reigns, in five separate periods between the 1750s and the 1820s: 1756-61, 1766-69, 1794-6, 1799–1802 and 1817-1823. Coffee first arrived in Sweden around 1674, but was little used until the turn of the 18th century when it became fashionable among the wealthy. In 1746, a royal edict was issued against coffee and tea due to "the misuse and excesses of tea and coffee drinking". Heavy taxes were levied on consumption, and failure to pay the tax on the substance resulted in fines and confiscation of cups and dishes. Later, coffee was banned completely; despite the ban, consumption conti ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Sweden
Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, Finland to the east, and is connected to Denmark in the southwest by a bridgetunnel across the Öresund. At , Sweden is the largest Nordic country, the third-largest country in the European Union, and the fifth-largest country in Europe. The capital and largest city is Stockholm. Sweden has a total population of 10.5 million, and a low population density of , with around 87% of Swedes residing in urban areas in the central and southern half of the country. Sweden has a nature dominated by forests and a large amount of lakes, including some of the largest in Europe. Many long rivers run from the Scandes range through the landscape, primarily ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Gustav III
Gustav III (29 March 1792), also called ''Gustavus III'', was King of Sweden from 1771 until his assassination in 1792. He was the eldest son of Adolf Frederick of Sweden and Queen Louisa Ulrika of Prussia. Gustav was a vocal opponent of what he saw as the abuse of political privileges seized by the nobility since the death of King Charles XII. Seizing power from the government in a coup d'état, called the Swedish Revolution, in 1772 that ended the Age of Liberty, he initiated a campaign to restore a measure of Royal autocracy, which was completed by the Union and Security Act of 1789, which swept away most of the powers exercised by the Swedish Riksdag (parliament) during the Age of Liberty, but at the same time it opened up the government for all citizens, thereby breaking the privileges of the nobility. A bulwark of enlightened absolutism, Gustav spent considerable public funds on cultural ventures, which were controversial among his critics, as well as military attempts t ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Posidonius
Posidonius (; grc-gre, wikt:Ποσειδώνιος, Ποσειδώνιος , "of Poseidon") "of Apamea (Syria), Apameia" (ὁ Ἀπαμεύς) or "of Rhodes" (ὁ Ῥόδιος) (), was a Greeks, Greek politician, astronomer, astrologer, geographer, historian, mathematician, and teacher native to Apamea, Syria. He was considered the most learned man of his time and, possibly, of the entire Stoicism, Stoic school. After a period learning Stoicism, Stoic philosophy from Panaetius in Athens, he spent many years in travel and scientific researches in Spain, Africa, Italy, Gaul, Liguria, Sicily and on the eastern shores of the Adriatic. He settled as a teacher at Rhodes where his fame attracted numerous scholars. Next to Panaetius he did most, by writings and personal lectures, to spread Stoicism to the Roman world, and he became well known to many leading men, including Pompey and Cicero. His works are now lost, but they proved a mine of information to later writers. The titles an ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |