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List of R1a Frequency by Population
Haplogroup R1a is one of the major classifications (called clades) of Y-chromosome types found in human male lines. It is widespread all across Eurasia. Many sample studies therefore carry information on the incidence of R1a and/or its subclassifications, in particular the dominant branching line represented by the haplogroups R1a1 and R1a1a. The table below collates information from a number of such sample studies, with incidence frequencies in sample data reported as percentages, along with the associated sample sizes.
  • 7.3K
  • 09 Nov 2022
Topic Review
Pepper-Box
The pepper-box revolver or simply pepperbox (also "pepper-pot", from its resemblance to the household pepper shakers) is a multiple-barrel firearm, mostly in the form of a handgun, that has three or more gun barrels in a coaxially revolving mechanism. Each barrel holds a single shot, and the shooter can manually rotate the whole barrel assembly to sequentially index each barrel into alignment with the lock/hammer, similar to operating a revolver cylinder. Pepperbox guns have existed for all action and ammunition systems: matchlock, wheellock, flintlock, snaplock, caplock, pinfire, rimfire and centerfire. While they are usually sidearms, a few long guns were also made. For example, Samuel Colt owned a three-barrel pepperbox matchlock musket from British India, and an eight-barrel pepperbox shotgun was designed in 1967 but never went into production.
  • 1.9K
  • 09 Nov 2022
Topic Review
Russian Financial Crisis (2014–2017)
The financial crisis in Russia in 2014–2015 was the result of the sharp devaluation of the Russian ruble beginning in the second half of 2014. A decline in confidence in the Russian economy caused investors to sell off their Russian assets, which led to a decline in the value of the Russian ruble and sparked fears of a Russian financial crisis. The lack of confidence in the Russian economy stemmed from at least two major sources. The first is the fall in the price of oil in 2014. Crude oil, a major export of Russia, declined in price by nearly 50% between its yearly high in June 2014 and 16 December 2014. The second is the result of international economic sanctions imposed on Russia following Russia's annexation of Crimea and the Russian military intervention in Ukraine. The crisis has affected the Russian economy, both consumers and companies, and regional financial markets, as well as Putin's ambitions regarding the Eurasian Economic Union. The Russian stock market in particular has experienced large declines, with a 30% drop in the RTS Index from the beginning of December through 16 December 2014. During the financial crisis, the economy turned to prevalent state ownership, with 60% of productive assets in the hands of the government. By 2016, the Russian economy rebounded with 0.3% GDP growth and was officially out of the recession. In January 2017, Russia had foreign currency reserves of around $391 billion, an inflation rate of 5.0% and interest rate of 10.0%.
  • 9.3K
  • 09 Nov 2022
Topic Review
Bowmouth Guitarfish
The bowmouth guitarfish (Rhina ancylostoma), also called the shark ray or mud skate, is a species of ray and a member of the family Rhinidae. Its evolutionary affinities are not fully resolved, though it may be related to true guitarfishes and skates. This rare species occurs widely in the tropical coastal waters of the western Indo-Pacific, at depths of up to 90 m (300 ft). Highly distinctive in appearance, the bowmouth guitarfish has a wide and thick body with a rounded snout and large shark-like dorsal and tail fins. Its mouth forms a W-shaped undulating line, and there are multiple thorny ridges over its head and back. It has a dorsal color pattern of many white spots over a bluish gray to brown background, with a pair of prominent black markings over the pectoral fins. This large species can reach a length of 2.7 m (8.9 ft) and weight of 135 kg (298 lb). Usually found near the sea floor, the bowmouth guitarfish prefers sandy or muddy areas near underwater structures. It is a strong-swimming predator of bony fishes, crustaceans, and molluscs. This species gives live birth to litters of two to eleven pups, which are nourished during gestation by yolk. The International Union for Conservation of Nature (IUCN) has assessed the bowmouth guitarfish as Vulnerable because it is widely caught by artisanal and commercial fisheries for its valuable fins and meat. It is viewed as a nuisance by trawlers, however, because its bulk and thorny skin cause it to damage netted catches. Habitat degradation and destruction pose an additional, significant challenge to this ray's survival. The bowmouth guitarfish adapts well to captivity and is displayed in public aquariums.
  • 1.7K
  • 09 Nov 2022
Topic Review
Timeline of Chagas Disease
This is a timeline of Chagas disease, describing major events such as scientific and medical developments, as well as major organizations and campaigns aimed at combating the disease.
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  • 09 Nov 2022
Topic Review
Psychographic Segmentation
Psychographic segmentation has been used in marketing research as a form of market segmentation which divides consumers into sub-groups based on shared psychological characteristics, including subconscious or conscious beliefs, motivations, and priorities to explain and predict consumer behavior. Developed in the 1970´s, it applies behavioral and social sciences to explore to understand consumers’ decision-making processes, consumer attitudes, values, personalities, lifestyles, and communication preferences. It complements demographic and socioeconomic segmentation, and enables marketers to target audiences with messaging to market brands, products or services. Some consider lifestyle segmentation to be interchangeable with psychographic segmentation, marketing experts argue that lifestyle relates specifically to overt behaviors while psychographics relate to consumers' cognitive style, which is based on their "patterns of thinking, feeling and perceiving".
  • 2.6K
  • 09 Nov 2022
Topic Review
Records Continuum Model
The Records Continuum Model (RCM) was created in the 1990s by Monash University academic Frank Upward with input from colleagues Sue McKemmish and Livia Iacovino as a response to evolving discussions about the challenges of managing digital records and archives in the discipline of Archival Science. The RCM was first published in Upward’s 1996 paper "Structuring the Records Continuum – Part One: Postcustodial principles and properties". Upward describes the RCM within the broad context of a continuum where activities and interactions transform documents into records, evidence and memory that are used for multiple purposes over time. Upward places the RCM within a post-custodial, postmodern and structuration conceptual framework. Australian academics and practitioners continue to explore, develop and extend the RCM and records continuum theory, along with international collaborators, via the Records Continuum Research Group (RCRG) at Monash University.
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  • 09 Nov 2022
Topic Review
Tall Tale
A tall tale is a story with unbelievable elements, related as if it were true and factual. Some tall tales are exaggerations of actual events, for example fish stories ("the fish that got away") such as, "That fish was so big, why I tell ya', it nearly sank the boat when I pulled it in!" Other tall tales are completely fictional tales set in a familiar setting, such as the European countryside, the American frontier, the Canadian Northwest, or the beginning of the Industrial Revolution. Events are often told in a way that makes the narrator seem to have been a part of the story; the tone is generally good-natured. The line between legends and tall tales is distinguished primarily by age; many legends exaggerate the exploits of their heroes, but in tall tales the exaggeration looms large, to the extent of dominating the story.
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  • 09 Nov 2022
Topic Review
Variobahn
The Variobahn, formerly known as the Variotram, is a German-designed model of articulated low-floor tram and light rail vehicle. Since its introduction in 1993, the Variobahn has been manufactured variously by ABB, Adtranz, Bombardier Transportation, and since 2001 by Stadler Rail. As of 2009, 254 trams have been ordered, with an additional 110 on option. A unit costs about €2.5 million. Operators include the Graz Holding, the Bergen Light Rail, the Chemnitz Tramway, Verkehrsverbund Rhein-Ruhr, the Helsinki Tramway, the Rhine Neckar Area Tramway and London Tramlink.
  • 2.2K
  • 09 Nov 2022
Topic Review
Jaguar S-Type
The Jaguar S-Type was an executive car that debuted at the 1998 Birmingham Motor Show and was marketed by Jaguar for model years 1999-2008, reviving the nameplate of the company's 1963-68 S-Type as a four-door notchback saloon. The S-Type received a mild facelift for model year 2005. The 2002 S-Type 4.2 Supercharged V8 at the time, was the fastest road production saloon car in the world. The S-Type was discontinued in late 2007 and replaced by the XF.
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  • 09 Nov 2022
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