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Aneuploidy
Aneuploidy is the presence of an abnormal number of chromosomes in a cell, for example a human cell having 45 or 47 chromosomes instead of the usual 46. It does not include a difference of one or more complete sets of chromosomes. A cell with any number of complete chromosome sets is called a euploid cell. An extra or missing chromosome is a common cause of some genetic disorders. Some cancer cells also have abnormal numbers of chromosomes. About 68% of human solid tumors are aneuploid. Aneuploidy originates during cell division when the chromosomes do not separate properly between the two cells (nondisjunction). Most cases of aneuploidy in the autosomes result in miscarriage, and the most common extra autosomal chromosomes among live births are 21, 18 and 13. Chromosome abnormalities are detected in 1 of 160 live human births. Autosomal aneuploidy is more dangerous than sex chromosome aneuploidy, as autosomal aneuploidy is almost always lethal to embryos that cease developing because of it.
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  • 09 Nov 2022
Topic Review
(6545) 1986 TR6
(6545) 1986 TR6, provisional designation 1986 TR6, is a Jupiter trojan from the Greek camp, approximately 53 kilometers (33 miles) in diameter. It was discovered on 5 October 1986, by Slovak astronomer Milan Antal at the Piwnice Astronomical Observatory in Poland. The dark D-type asteroid has a rotation period of 16.3 hours and belongs to the 90 largest Jupiter trojans. It has not been named since its numbering in September 1995.
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  • 09 Nov 2022
Topic Review
Three Roots
The Three Roots (Tibetan: tsa sum) of the Tibetan Buddhist tradition are the lama (Sanskrit: guru), yidam (Sanskrit: ishtadevata) and protector, which may be a khandroma (Sanskrit: dakini) or chokyong (Sanskrit: dharmapala). The Three Roots are the second of three Tibetan Buddhist refuge formulations, the Outer, Inner and Secret forms of the Three Jewels. The 'Outer' form is the 'Triple Gem', (Sanskrit:triratna), the 'Inner' is the Three Roots and the 'Secret' form is the 'Three Bodies' or trikaya of a Buddha. These alternative refuge formulations are employed by those undertaking Deity Yoga and other tantric practices within the Tibetan Buddhist Vajrayana tradition as a means of recognizing the universality of Buddha Nature. The Three Roots are commonly mentioned in the Nyingma and Kagyu literature of Tibetan Buddhism. Unlike most aspects of Tibetan Buddhism, which originated in India, the Three Roots may be an original Tibetan formulation from the time of Padmasambhava. The functions of the Three Roots are: In the Yangzab compilation of Dzogchen texts the 'Yangzab Three Roots' is the primary Deity Yoga practice. The Three Roots in this cycle are: Guru Rinpoche (the guru), Hayagriva (the yidam), and Vajravarahi (the dakini). This empowerment is required for the practitioner to study the Yangzab Treasure teaching cycle. The three roots are symbolized in the Gankyil.
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  • 09 Nov 2022
Topic Review
Neo-Ottomanism
Neo-Ottomanism (Turkish: Yeni Osmanlıcılık or neo-Osmanlıcılık) is a reactionary, revisionist, monarchist, conservative and Islamist political ideology in Turkey that discredits the Turkish secular nationalist republic and its reforms, and glorifies the Ottoman dynasty and its traditionalist establishments like the caliphate. It is also an irredentist and imperialist Turkish political ideology that, in its broadest sense, advocates to honor the Ottoman past of Turkey and promotes greater political engagement of the Republic of Turkey within regions formerly under the rule of the Ottoman Empire, the predecessor state that covered the territory of modern Turkey among others. The term has been associated with Recep Tayyip Erdoğan's irredentist, interventionist and expansionist foreign policy in the Eastern Mediterranean and the neighboring Cyprus, Greece, Iraq, Syria, as well as in Africa, including Libya, and Nagorno-Karabakh. However, the term has been rejected by members of the Erdoğan Government, such as the former Foreign Minister Ahmet Davutoğlu and Parliament Speaker Mustafa Şentop.
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  • 01 Jan 2026
Topic Review
Polycom
Polycom, now a part of Plantronics, was an American multinational corporation that develops video, voice and content collaboration and communication technology. Polycom was co-founded in 1990 by Brian L Hinman and Jeffrey Rodman. In 2018 Polycom was acquired by Plantronics and in 2019 the name of the combined entity was changed to Poly. On March 28, 2022 HP Inc. announced it would be acquiring Poly (company) in a deal totaling $1.7 billion USD.
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  • 09 Nov 2022
Topic Review
J/Psi Meson
The J/ψ (J/psi) meson /ˈdʒeɪ ˈsaɪ ˈmiːzɒn/ or psion is a subatomic particle, a flavor-neutral meson consisting of a charm quark and a charm antiquark. Mesons formed by a bound state of a charm quark and a charm anti-quark are generally known as "charmonium". The J/ψ is the most common form of charmonium, due to its spin of 1 and its low rest mass. The J/ψ has a rest mass of 3.0969 GeV/c2, just above that of the ηc (2.9836 GeV/c2), and a mean lifetime of 7.2×10−21 s. This lifetime was about a thousand times longer than expected. Its discovery was made independently by two research groups, one at the Stanford Linear Accelerator Center, headed by Burton Richter, and one at the Brookhaven National Laboratory, headed by Samuel Ting of MIT. They discovered they had actually found the same particle, and both announced their discoveries on 11 November 1974. The importance of this discovery is highlighted by the fact that the subsequent, rapid changes in high-energy physics at the time have become collectively known as the "November Revolution". Richter and Ting were awarded the 1976 Nobel Prize in Physics.
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  • 09 Nov 2022
Topic Review
Bharat Stage Emission Standards
Bharat stage emission standards (BSES) are emission standards instituted by the Government of India to regulate the output of air pollutants from internal combustion engines and Spark-ignition engines equipment, including motor vehicles. The standards and the timeline for implementation are set by the Central Pollution Control Board under the Ministry of Environment & Forests and climate change. The standards, based on European regulations were first introduced in 2000. Progressively stringent norms have been rolled out since then. All new vehicles manufactured after the implementation of the norms have to be compliant with the regulations. Since October 2010, Bharat Stage (BS) III norms have been enforced across the country. In 13 major cities, Bharat Stage IV emission norms have been in place since April 2010 and it has been enforced for entire country since April 2017. In 2016, the Indian government announced that the country would skip the BS-V norms altogether and adopt BS-VI norms by 2020. On November 15, 2017 The Petroleum Ministry of India in consultation with Public Oil Marketing Companies decided to bring forward the date of BS-VI grade auto fuels in NCT of Delhi with effect from April 1, 2018 instead of April 1, 2020. In fact, Petroleum Ministry OMCs were asked to examine the possibility of introduction of BS-VI auto fuels in the whole of NCR area from April 1, 2019. This huge step was taken due the heavy problem of air pollution faced by Delhi which became worse around this year. The decision was met with disarray by the automobile companies as they had planned the development according to roadmap for 2020. The phasing out of 2-stroke engine for two wheelers, the cessation of production of Maruti 800 & introduction of electronic controls have been due to the regulations related to vehicular emissions. While the norms help in bringing down pollution levels, it invariably results in increased vehicle cost due to the improved technology & higher fuel prices. However, this increase in private cost is offset by savings in health costs for the public, as there is lesser amount of disease causing particulate matter and pollution in the air. Exposure to air pollution can lead to respiratory and cardiovascular diseases, which is estimated to be the cause for 6.2 lakh early deaths in 2010, and the health cost of air pollution in India has been assessed at 3% of its GDP.
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  • 09 Nov 2022
Topic Review
Memory Augmentation
Memory augmentation is the process by which one's ability to retain information is increased. The retrieval of memory has been theorized to be untrustworthy, and it can be partially inaccurate and not totally reliable (see more: Recovered memory.) Ubiquitous Memory Systems have been invented in order to reduce these memory mistakes. A study conducted by students of the Information Science Department in Nara, Japan sought to measure different types of memory augmentation. They used a computer system, the "Ubiquitous Memories," to demonstrate if the technology aided to augmentation better than other methods such as notes with a pen and paper, portraits used in a previous trial experiment, and just plain human memory. The results were that the Ubiquitous Memories aided in retrieving memory, and decreased the likelihood of mistakes in comparison to other methods. Some researchers have even gone so far as to create mixed-reality simulations to assist individuals in improving their memories. Many of these systems implement the method of loci which involves using the spatial layout of a familiar place to help individuals remember certain things. For example, one might attempt to remember a packing list for a trip by imagining the items around their room. Memory augmentation not only refers to our ability to recall information accurately, it also refers to our ability to encode long-term information quickly. Some researchers suggest that through using augmented reality interfaces, we have the ability to memorize information and store it in our long-term memory after only being exposed to it once. Specifically, the function of these interfaces is to stimulate parts of the brain that are essential to memory such as the hippocampus, neocortex, and entorhinal cortex which would result in the acquisition of episodic memory for things we would normally use long-term semantic memory to recall.
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  • 09 Nov 2022
Topic Review
Thermodynamics of the Universe
The thermodynamics of the universe is dictated by which form of energy dominates it - relativistic particles which are referred to as radiation, or non-relativistic particles which are referred to as matter. The former are particles whose rest mass is zero or negligible compared to their energy, and therefore move at the speed of light or very close to it; the latter are particles whose kinetic energy is much lower than their rest mass and therefore move much slower than the speed of light. The intermediate case is not treated well analytically.
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  • 09 Nov 2022
Topic Review
Submarine Canyon
A submarine canyon is a steep-sided valley cut into the seabed of the continental slope, sometimes extending well onto the continental shelf, having nearly vertical walls, and occasionally having canyon wall heights of up to 5 km, from canyon floor to canyon rim, as with the Great Bahama Canyon. Just as above-sea-level canyons serve as channels for the flow of water across land, submarine canyons serve as channels for the flow of turbidity currents across the seafloor. Turbidity currents are flows of dense, sediment laden waters that are supplied by rivers, or generated on the seabed by storms, submarine landslides, earthquakes, and other soil disturbances. Turbidity currents travel down slope at great speed (as much as 70 km/h), eroding the continental slope and finally depositing sediment onto the abyssal plain, where the particles settle out. About 3% of submarine canyons include shelf valleys that have cut transversely across continental shelves, and which begin with their upstream ends in alignment with and sometimes within the mouths of large rivers, such as the Congo River and the Hudson Canyon. About 28.5% of submarine canyons cut back into the edge of the continental shelf, whereas the majority (about 68.5%) of submarine canyons have not managed at all to cut significantly across their continental shelves, having their upstream beginnings or "heads" on the continental slope, below the edge of continental shelves. The formation of submarine canyons is believed to occur as the result of at least two main process: 1) erosion by turbidity current erosion; and 2) slumping and mass wasting of the continental slope. While at first glance, the erosion patterns of submarine canyons may appear to mimic those of river-canyons on land, due to the markedly different erosion processes that have been found to take place underwater at the soil/ water interface, several notably different erosion patterns have been observed in the formation of typical submarine canyons. Many canyons have been found at depths greater than 2 km below sea level. Some may extend seawards across continental shelves for hundreds of kilometres before reaching the abyssal plain. Ancient examples have been found in rocks dating back to the Neoproterozoic. Turbidites are deposited at the downstream mouths or ends of canyons, building an abyssal fan.
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  • 09 Nov 2022
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