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(225088) 2007 OR10
(225088) 2007 OR10, proposed to be named Gonggong, is a likely dwarf planet in the Solar System beyond Neptune, and is a member of the scattered disc. It has a highly eccentric and inclined orbit during which it ranges from 33–101 astronomical units (4.9–15.1 billion kilometers) from the Sun. (As of 2019), its distance from the Sun is 88 AU (1.32×1010 km; 8.2×109 mi), and it is the sixth-farthest known Solar System object. 2007 OR10 is in a 3:10 orbital resonance with Neptune, in which it completes three orbits around the Sun for every ten orbits completed by Neptune. 2007 OR10 was discovered in July 2007 by American astronomers Megan Schwamb, Michael Brown, and David Rabinowitz at the Palomar Observatory, and the discovery was announced in January 2009. At 1,230 km (760 mi) in diameter, 2007 OR10 is approximately the size of Pluto's moon Charon, and is the fifth-largest known trans-Neptunian object in the Solar System. It is sufficiently massive to be gravitationally rounded, thereby qualifying for dwarf planet status. Its large mass also makes retention of a tenuous atmosphere of methane just possible, though such an atmosphere would slowly escape into space. 2007 OR10 is currently the largest known body in the Solar System without an official name, but in 2019, the discoverers hosted an online poll for the general public to help choose a name for the object, and the name Gonggong won. The winning name is derived from Gonggong, a Chinese water god responsible for chaos, floods and the tilt of the Earth. 2007 OR10 is red in color, likely due to the presence of organic compounds called tholins on its surface. Water ice is also present on its surface, which hints at a brief period of cryovolcanic activity in the distant past. 2007 OR10 rotates slowly compared to other trans-Neptunian objects, which typically have rotation periods less than 12 hours, which may be due to its natural satellite, provisionally designated S/2010 (225088) 1.
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  • 02 Dec 2022
Topic Review
Boreal (Age)
In paleoclimatology of the Holocene, the Boreal was the first of the Blytt-Sernander sequence of north European climatic phases that were originally based on the study of Danish peat bogs, named for Axel Blytt and Rutger Sernander, who first established the sequence. In peat bog sediments, the Boreal is also recognized by its characteristic pollen zone. It was preceded by the Younger Dryas, the last cold snap of the Pleistocene, and followed by the Atlantic, a warmer and moister period than our most recent climate. The Boreal, transitional between the two periods, varied a great deal, at times having within it climates like today's.
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  • 02 Dec 2022
Topic Review
Edit Distance
In computational linguistics and computer science, edit distance is a way of quantifying how dissimilar two strings (e.g., words) are to one another by counting the minimum number of operations required to transform one string into the other. Edit distances find applications in natural language processing, where automatic spelling correction can determine candidate corrections for a misspelled word by selecting words from a dictionary that have a low distance to the word in question. In bioinformatics, it can be used to quantify the similarity of DNA sequences, which can be viewed as strings of the letters A, C, G and T. Different definitions of an edit distance use different sets of string operations. Levenshtein distance operations are the removal, insertion, or substitution of a character in the string. Being the most common metric, the term Levenshtein distance is often used interchangeably with edit distance.
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  • 02 Dec 2022
Topic Review
Encyclopaedia Metallum
Encyclopaedia Metallum: The Metal Archives (commonly known as Metal Archives per the URL or just MA) is a website which lists bands from various forms of heavy metal music. Encyclopaedia Metallum was described by Matt Sullivan of Nashville Scene as "the Internet's central database for all that is 'tr00' in the metal world." Terrorizer described the site as "a fully-exhaustive list of pretty much every metal band ever, with full discographies, an active forum and an interlinking members list that shows the ever-incestuous beauty of the metal scene". Nevertheless, there are exceptions for bands which fall under disputed genres not accepted by the website. Encyclopaedia Metallum attempts to provide comprehensive information on each band, such as a discography, logos, pictures, lyrics, line-ups, biography, trivia and user-submitted reviews. The site also provides a system for submitting bands to the archives. The website is free of advertisements and is run completely independently.
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Topic Review
Guitarrón Chileno
The Guitarrón Chileno (literally: "large Chilean guitar") is a guitar-shaped plucked string instrument from Chile , with 25 or 24 (rarely) strings. Its primary contemporary use is as the instrumental accompaniment for the traditional Chilean genre of singing poetry known as Canto a lo Poeta, though a few virtuosi have also begun to develop the instrument's solo possibilities.
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  • 02 Dec 2022
Topic Review
Shooting of Sammy Yatim
The death of Sammy Yatim occurred early in the morning of July 27, 2013, in Toronto, Ontario, Canada. Yatim, an 18-year-old Toronto male armed with a switchblade knife, was shot at nine times, and was hit by eight of the shots fired by 30-year-old Toronto Police Service (TPS) officer James Forcillo. After being shot, while lying on the floor of the streetcar he was tasered. He later died from the injuries. The incident occurred after Yatim, brandishing a 12 cm (4.7 in) switchblade knife in a Toronto streetcar, advanced on a passenger, threatened other passengers, and exposed himself. The confrontation between Yatim and the police was recorded and footage of it was released publicly, prompting strong reactions across Canada. On August 19, 2013, Forcillo was charged with second-degree murder. On July 30, 2014, he was also charged with attempted murder. On January 25, 2016, he was found not guilty of second-degree murder and manslaughter, but guilty of attempted murder. On July 28, he was sentenced to six years in prison. The next day, he was granted bail pending an appeal of the court's sentence. His appeal was denied and he was granted parole after serving 2 years in prison. This incident was the only time an on-duty Ontario officer was charged and convicted in the death of a person since the inception of the Special Investigations Unit (SIU) in 1990.
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Topic Review
Davidic Line
The Davidic line or House of David (Hebrew: בית דוד‎, romanized: Beit David) refers to the lineage of the Israelite king David through texts in the Hebrew Bible, the New Testament, and through the succeeding centuries. According to the Bible, David, of the Tribe of Judah, was the third king of the United Monarchy of Israel and Judah. He was later succeeded by his son, Solomon. After Solomon's death, the ten northern tribes rejected the Davidic line, refusing to accept Solomon's son, Rehoboam, and instead chose as king Jeroboam and formed the northern Kingdom of Israel. The southern tribes of Judah and Benjamin remained loyal to the House of David, and this kingdom came to be known as the Kingdom of Judah. All subsequent kings of Judah, except Athaliah, are said to be direct descendants of David. The kingdom fell to the Neo-Babylonian Empire in 587/6 BCE. The Hasmoneans, who established their own monarchy in Judea in the 2nd century BCE, were not considered connected to the Davidic line nor to the Tribe of Judah. In Judaism and Christianity, the Davidic Line is the bloodline from which the Hebrew Messiah has a patrilineal descent. In Jewish eschatology, the Messiah is a future Jewish king from the Davidic line, who is expected to rule the Jewish people during the Messianic Age and world to come. The Christian gospels claim that Jesus descends from the Davidic line and is therefore the legitimate Hebrew Messiah. The New Testament books of Matthew and Luke give two different accounts of the genealogy of Jesus that trace back to David.
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  • 02 Dec 2022
Topic Review
Chiropractic
Chiropractic is a form of alternative medicine mostly concerned with the diagnosis and treatment of mechanical disorders of the musculoskeletal system, especially the spine. Proponents claim that such disorders affect general health via the nervous system, through vertebral subluxation, claims which are demonstrably false. The main chiropractic treatment technique involves manual therapy, especially spinal manipulation therapy (SMT), manipulations of other joints and soft tissues. Its foundation is at odds with mainstream medicine, and chiropractic is sustained by pseudoscientific ideas such as subluxation and "innate intelligence" that reject science. Chiropractors are not medical doctors. Numerous controlled clinical studies of treatments used by chiropractors have been conducted, with conflicting results. Systematic reviews of this research have not found evidence that chiropractic manipulation is effective, with the possible exception of treatment for back pain. A critical evaluation found that collectively, spinal manipulation was ineffective at treating any condition. Spinal manipulation may be cost-effective for sub-acute or chronic low back pain but the results for acute low back pain were insufficient. The efficacy and cost-effectiveness of maintenance chiropractic care are unknown. There is not sufficient data to establish the safety of chiropractic manipulations. It is frequently associated with mild to moderate adverse effects, with serious or fatal complications in rare cases. There is controversy regarding the degree of risk of vertebral artery dissection, which can lead to stroke and death, from cervical manipulation. Several deaths have been associated with this technique and it has been suggested that the relationship is causative, a claim which is disputed by many chiropractors. Chiropractic is well established in the United States, Canada, and Australia. It overlaps with other manual-therapy professions such as osteopathy and physical therapy. Most who seek chiropractic care do so for low back pain. Back and neck pain are considered the specialties of chiropractic, but many chiropractors treat ailments other than musculoskeletal issues. Many chiropractors describe themselves as primary care providers, but the chiropractic clinical training does not support the requirements to be considered primary care providers, so their role on primary care is limited and disputed. Chiropractic has two main groups: "straights", now the minority, emphasize vitalism, "innate intelligence", and consider vertebral subluxations to be the cause of all disease; "mixers", the majority, are more open to mainstream views and conventional medical techniques, such as exercise, massage, and ice therapy. D. D. Palmer founded chiropractic in the 1890s, after saying he received it from "the other world", and his son B. J. Palmer helped to expand it in the early 20th century. Throughout its history, chiropractic has been controversial. Despite the overwhelming evidence that vaccination is an effective public health intervention, among chiropractors there are significant disagreements over the subject, which has led to negative impacts on both public vaccination and mainstream acceptance of chiropractic. The American Medical Association called chiropractic an "unscientific cult" in 1966 and boycotted it until losing an antitrust case in 1987. Chiropractic has had a strong political base and sustained demand for services; in recent decades, it has gained more legitimacy and greater acceptance among conventional physicians and health plans in the United States.
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  • 02 Dec 2022
Topic Review
Examination of Apollo Moon Photographs
The examination of Apollo Moon photographs is an endeavour undertaken by certain people engaged in the debate as to the merits of Moon landing conspiracy theories, despite the abundance of third-party evidence for Apollo Moon landings. A number of allegations and refutations with a variable degree of notability are put forward due to this examination.
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  • 02 Dec 2022
Topic Review
Protein Film Voltammetry
In electrochemistry, protein film voltammetry (or protein film electrochemistry, or direct electrochemistry of proteins) is a technique for examining the behavior of proteins immobilized (either adsorbed or covalently attached) on an electrode. The technique is applicable to proteins and enzymes that engage in electron transfer reactions and it is part of the methods available to study enzyme kinetics. Provided that it makes suitable contact with the electrode surface (electron transfer between the electrode and the protein is direct) and provided that it is not denatured, the protein can be fruitfully interrogated by monitoring current as a function of electrode potential and other experimental parameters. Various electrode materials can be used. Special electrode designs are required to address membrane-bound proteins.
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