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The Heritage Foundation
The Heritage Foundation (abbreviated to Heritage) is an American conservative think tank based in Washington, D.C., primarily geared towards public policy. The foundation took a leading role in the conservative movement during the presidency of Ronald Reagan, whose policies were taken from Heritage's policy study Mandate for Leadership. Since then, The Heritage Foundation has continued to have a significant influence in U.S. public policy making, and is considered to be one of the most influential conservative public policy organizations in the United States .
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  • 07 Nov 2022
Topic Review
GRACE-FO
The Gravity Recovery and Climate Experiment (GRACE) was a joint mission of NASA and the German Aerospace Center (DLR). Twin satellites took detailed measurements of Earth's gravity field anomalies from its launch in March 2002 to the end of its science mission in October 2017. The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) is a continuation of the mission on near-identical hardware, launched in May 2018. By measuring gravity anomalies, GRACE showed how mass is distributed around the planet and how it varies over time. Data from the GRACE satellites is an important tool for studying Earth's ocean, geology, and climate. GRACE was a collaborative endeavor involving the Center for Space Research at the University of Texas at Austin, NASA's Jet Propulsion Laboratory, the German Aerospace Center and Germany's National Research Center for Geosciences, Potsdam. The Jet Propulsion Laboratory was responsible for the overall mission management under the NASA ESSP (Earth System Science Pathfinder) program. The principal investigator is Byron Tapley of the University of Texas Center for Space Research, and the co-principal investigator is Christoph Reigber of the GeoForschungsZentrum (GFZ) Potsdam. The two GRACE satellites (GRACE-1 and GRACE-2) were launched from Plesetsk Cosmodrome, Russia, on a Rockot (SS-19 + Breeze upper stage) launch vehicle on 17 March 2002. The spacecraft were launched to an initial altitude of approximately 500 km at a near-polar inclination of 89°. During normal operations, the satellites were separated by 220 km along their orbit track. This system was able to gather global coverage every 30 days. GRACE far exceeded its 5-year design lifespan, operating for 15 years until the decommissioning of GRACE-2 on 27 October 2017. Its successor, GRACE-FO, was successfully launched on 22 May 2018. In 2019, a glacier in West Antarctica was named after the GRACE mission.
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  • 07 Nov 2022
Topic Review
Babine-Witsuwit'en Language
Babine–Witsuwit'en or Nadot'en-Wets'uwet'en is an Athabaskan language spoken in the Central Interior of British Columbia. Its closest relative is Carrier. Because of this linguistic relationship together with political and cultural ties, Babine–Witsuwit'en is often referred to as Northern Carrier or Western Carrier. Specialist opinion is, however, that it should be considered a separate, though related, language (Kari 1975, Story 1984, Kari and Hargus 1989). A term used briefly in the 1990s is Bulkley Valley – Lakes District Language, abbreviated BVLD. Ethnologue uses the bare name Babine for the language as a whole, not just for the Babine dialect. As its name suggests, Babine–Witsuwit'en consists of two main dialects, Babine (Nedut'en) and Witsuwit'en. Babine is spoken around Babine Lake, Trembleur Lake, and Takla Lake. Witsuwit'en is spoken in the Bulkley Valley, around Broman Lake, and in the vicinity of Skins Lake. The two dialects are very similar and are distinguished primarily by the fact that in Babine but not in Witsuwit'en the Athabaskan front velar series have become palatal affricates. Like most languages native to British Columbia, Babine–Witsuwit'en is an endangered language. It is spoken by a minority of the population, primarily elders. There are 161 fluent and 159 partial speakers of the Babine dialect and 131 fluent and 61 partial speakers of the Witsuwit'en dialect. At most, a handful of children are still speaking the language.
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Topic Review
Sadhu
A sadhu (IAST: sādhu (male), sādhvī or sādhvīne (female)), also spelled saddhu, is a religious ascetic, mendicant (monk) or any holy person in Hinduism and Jainism who has renounced the worldly life. They are sometimes alternatively referred to as jogi, sannyasi or vairagi. It literally means one who practises a ″sadhana″ or keenly follows a path of spiritual discipline. Although the vast majority of sādhus are yogīs, not all yogīs are sādhus. The sādhu is solely dedicated to achieving mokṣa (liberation), the fourth and final aśrama (stage of life), through meditation and contemplation of Brahman. Sādhus often wear simple clothing, such saffron-coloured clothing in Hinduism, white or nothing in Jainism, symbolising their sannyāsa (renunciation of worldly possessions). A female mendicant in Hinduism and Jainism is often called a sadhvi, or in some texts as aryika.
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  • 10 Nov 2022
Topic Review
Camp Lazlo
Camp Lazlo (stylized as CAMP LAZLO!) is an American animated television series created by Joe Murray for Cartoon Network. It was produced by Cartoon Network Studios. The show revolves around Lazlo, a spider monkey who attends a Boy Scout-like summer camp with a cast of anthropomorphic animal characters. The series has a style of humor similar to the Nickelodeon series Rocko's Modern Life (which Murray also created and is most known for) SpongeBob SquarePants and The Powerpuff Girls. The series premiered on Cartoon Network on July 8, 2005 at 8:00 p.m. ET/PT with five seasons, 61 episodes, and an hour-long television special. During its run, the series won three Emmy Awards and three Pulcinella Awards, and was also nominated for another Emmy and an Annie Award.
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  • 07 Nov 2022
Topic Review
Sexual Antagonistic Coevolution
Sexual antagonistic co-evolution is the relationship between males and females where sexual morphology changes over time to counteract the opposite's sex traits to achieve the maximum reproductive success. This has been compared to an arms race between sexes. In many cases, male mating behavior is detrimental to the female's fitness. For example, when insects reproduce by means of traumatic insemination, it is very disadvantageous to the female's health. During mating, males will try to inseminate as many females as possible, however, the more times a female's abdomen is punctured, the less likely she is to survive. Females that possess traits to avoid multiple matings will be more likely to survive, resulting in a change in morphology. In males, genitalia is relatively simple and more likely to vary among generations compared to female genitalia. This results in a new trait that females have to avoid in order to survive. Additionally, sexual antagonistic co-evolution can be the cause of rapid evolution, as is thought to be the case in seminal proteins known as Acps in species of Drosophila melanogaster. While Acps facilitate the mutually beneficial outcome of increased progeny production, several Acps have detrimental effects on female fitness as they are toxic and shorten her lifespan. This leads to antagonistic co-evolution, as the female must evolve in order to defend herself. When female Drosophila melanogaster are experimentally prevented from co-evolving with males, males rapidly adapt to the static female phenotype. This male adaptation leads to a reduction in female survivorship, which is mediated by an increased rate of remating and increased toxicity of Acps in seminal fluid. Since non-reproductive proteins do not feel the same evolutionary pressure as Acps, they are not evolving nearly as quickly. Consistent with the arms race theory, DNA analyses reveal a two-fold increase in Acp divergence relative to non-reproductive proteins
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Topic Review
Travis (Chimpanzee)
Travis (October 21, 1995 – February 16, 2009) was a male common chimpanzee (Pan troglodytes) who, in February 2009, mauled his owner's friend in Stamford, Connecticut. He blinded her, severed several body parts and lacerated her face. He was shot dead by a police officer. As an animal actor, Travis had appeared in several television shows and commercials, including spots for Pepsi and Old Navy. He had also appeared on The Maury Povich Show, The Man Show, and a television pilot that featured Sheryl Crow and Michael Moore.
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  • 07 Nov 2022
Topic Review
French Cruiser Dupleix (1930)
Dupleix was the fourth unit of the Suffren class. She entered service in 1933 and spent the interwar period in the Mediterranean. She participated in the International Patrol during the Spanish Civil War. September 1939 found her still in Toulon. She participated in the search for the Graf Spee in the Atlantic before returning to Toulon. The only time she fired her guns in anger was during the bombardment of Vado, Italy in mid-June 1940. She was at Toulon at the time of the Franco-German Armistice in June 1940. She remained at Toulon until the French Fleet there was scuttled in late November 1942. She was subsequently raised by the Italians in 1943. She was named in honour of Joseph François, Marquis Dupleix (1697 - 1763) a French trader in the service of La Compagnie des Indes. He travelled between North America and India. He was appointed Governor-General of French India in 1742. A post he held until his death in 1763.
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Topic Review
Great Oxygenation Event
The Great Oxygenation Event, the beginning of which is commonly known in scientific media as the Great Oxidation Event (GOE, also called the Oxygen Catastrophe, Oxygen Crisis, Oxygen Holocaust, Oxygen Revolution, or Great Oxidation) was the biologically induced appearance of dioxygen (O2) in Earth's atmosphere. Geological, isotopic, and chemical evidence suggests that this major environmental change happened around 2.45 billion years ago (2.45 Ga), during the Siderian period, at the beginning of the Proterozoic eon. The causes of the event remain unclear. (As of 2016), the geochemical and biomarker evidence for the development of oxygenic photosynthesis before the Great Oxidation Event has been mostly inconclusive. Oceanic cyanobacteria, which evolved into coordinated (but not multicellular or even colonial) macroscopic forms more than 2.3 billion years ago (approximately 200 million years before the GOE), are believed to have become the first microbes to produce oxygen by photosynthesis. Before the GOE, any free oxygen they produced was chemically captured by dissolved iron or by organic matter. The GOE started when oxygen produced by the cyanobacteria started escaping into the atmosphere, after other oxygen reservoirs were filled. The increased production of oxygen set Earth's original atmosphere off-balance. Free oxygen is toxic to obligate anaerobic organisms, and the rising concentrations may have destroyed most such organisms at the time. A spike in chromium contained in ancient rock-deposits formed underwater shows the accumulation had been washed off from the continental shelves. Chromium is not easily dissolved and its release from rocks would have required the presence of a powerful acid. One such acid, sulfuric acid (H2SO4), might have formed through bacterial reactions with pyrite. Mats of oxygen-producing cyanobacteria can produce a thin layer, one or two millimeters thick, of oxygenated water in an otherwise anoxic environment even under thick ice; before oxygen started accumulating in the atmosphere, these organisms would already have adapted to oxygen. Additionally, the free oxygen would have reacted with atmospheric methane, a greenhouse gas, greatly reducing its concentration and triggering the Huronian glaciation, possibly the longest episode of glaciation in Earth's history and called "snowball Earth". Eventually, the evolution of aerobic organisms that consumed oxygen established an equilibrium in its availability. Free oxygen has been an important constituent of the atmosphere ever since.
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  • 10 Nov 2022
Topic Review
Mount Polley Tailings Spill
The Mount Polley tailings spill occurred in the Cariboo region of central British Columbia, Canada . The spill began 4 August 2014 with a breach of the Imperial Metals-owned Mount Polley copper, gold and silver mine tailings pond, releasing its water and slurry with years worth of mining waste into Polley Lake. The spill flooded Polley Lake, creating a plug at Hazeltine Creek, and continued into nearby Quesnel Lake and Cariboo River. By 8 August the four-square-kilometre (1.5 sq mi) sized tailings pond had been emptied of the majority of supernatant (process water) that sits atop the settled crushed rock solids (mining waste, or 'tailings'). The cause of the dam breach and subsequent tailings spill has been investigated with a final report published 31 January 2015. Imperial Metals had a history of operating the pond beyond capacity since at least 2011. Remediation and reconstruction has been underway at the site since 2014. These efforts have included investigation on impacts to human health and safety and affected ecosystems while removing the tailings spill, reconstructing creek shorelines, installing fish habitats, and replanting trees and other local vegetation. Investigation by the remediation team showed elevated levels of selenium, arsenic and other metals consistent with historical tests before the dam breach. These initial reports had been concerned about the chemical impact of the tailings spill on the surrounding environment, but it was determined through subsequent investigation and remediation that the challenge posed by tailings spill was physical in nature.
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