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Topic Review
UNAVCO
UNAVCO is a non-profit university-governed consortium that facilitates geoscience research and education using Geodesy. UNAVCO is funded by the National Science Foundation (NSF) and The National Aeronautics and Space Administration (NASA) to support geoscience research around the world. UNAVCO operates the GAGE Facility (Geodetic Facility for the Advancement of Geoscience) on behalf of the NSF and NASA. As a university-governed consortium, UNAVCO supports the goals of the academic scientific community. UNAVCO has 120 US academic members and supports over 110 organizations globally as associate members.
  • 2.2K
  • 17 Nov 2022
Topic Review
CDKN2A/B Homozygous Deletions in Astrocytomas
The CDKN2A and CDKN2B genes are located on the short arm of chromosome 9. CDKN2A encodes for two proteins, p14 and p16, and CDKN2B encodes for p15. These proteins regulate cell growth and angiogenesis. Interpreting the impact of CDKN2A/B alterations on astrocytoma prognosis is complicated by the changes in tumour classification and a lack of uniform standards for testing CDKN2A/B. While the prognostic impact of CDKN2A/B HD is established, the role of different CDKN2A/B alterations—heterozygous deletions (HeD), point mutations, and promoter methylation—is less clear. Consequently, how these alternations should be incorporated into patient management remains controversial.
  • 2.2K
  • 05 Jul 2023
Topic Review
Collective Leadership in the Soviet Union
Collective leadership (Russian: коллективное руководство, kollektivnoye rukovodstvo), or Collectivity of leadership (Russian: коллективность руководства, kollektivnost rukovodstva), was considered the ideal form of governance in the Union of Soviet Socialist Republics (USSR) and other socialist states espousing communism. Its main task was to distribute powers and functions among the Politburo and the Central Committee of the Communist Party of the Soviet Union, as well as the Council of Ministers, to hinder any attempts to create a one-man dominance over the Soviet political system by a Soviet leader, such as that seen under Joseph Stalin 's rule. On the national level, the heart of the collective leadership was officially the Central Committee of the Communist Party. Collective leadership was characterised by limiting the powers of the General Secretary and the Chairman of the Council of Ministers as related to other offices by enhancing the powers of collective bodies, such as the Politburo. Collective leadership was introduced following Stalin's death in 1953 and subsequent party leaders ruled as part of a collective. First Secretary Nikita Khrushchev criticized Stalin's dictatorial rule at the 20th Party Congress, but his increasingly erratic decisions lead to his ouster in 1964. He was replaced in his posts by Leonid Brezhnev as First Secretary and by Alexei Kosygin as Premier. Though Brezhnev gained more and more prominence over his colleagues, he retained the Politburo's support by consulting its members on all policies. Collective leadership was maintained under Yuri Andropov and Konstantin Chernenko. Mikhail Gorbachev's reforms espoused open discussion, leading to members of the leadership openly disagreeing on how little or how much reform was needed to rejuvenate the Soviet system.
  • 2.2K
  • 21 Oct 2022
Topic Review
Diabrotica Species
The genus Diabrotica has over 400 described species, the majority of them neotropical. However, only three species of neotropical Diabrotica are considered agricultural pests, D. speciosa, D. balteata, and D. viridula. D. speciosa and D. balteata are polyphagous both as adults and during the larval stage. D. viridula are stenophagous during the larval stage, feeding essentially on maize roots, and polyphagous as adults. The larvae of the three species are pests on maize, but D. speciosa larvae also feed on potatoes and peanuts, while D. balteata larvae feed on beans and peanuts. None of these species express a winter/dry season egg diapause, like several North American species. Instead they have several continuous, latitude-mediated generations per year. This hinders the use of crop rotation as a management tool, although early planting can help in the temperate regions of the distribution of D. speciosa. Their know parasitoids do not exert much control on Diabrotica populations, or show potential for inundative biocontrol plans. Management options are limited to insecticide applications and Bt GM maize. Other techniques that show promise are products using Beauveria bassiana and Heterorhabditis bacteriophora, semiochemical attractants for monitoring purposes or as toxic baits, and plant resistance.
  • 2.2K
  • 30 Jul 2020
Topic Review
Pre-mRNA Splicing
Pre-mRNA splicing is an essential process for gene expression in higher eukaryotes, which requires a high order of accuracy. Mutations in splicing factors or regulatory elements in pre-mRNAs often result in many human diseases. Myelodysplastic syndrome (MDS) is a heterogeneous group of chronic myeloid neoplasms characterized by many symptoms and a high risk of progression to acute myeloid leukemia. Recent findings indicate that mutations in splicing factors represent a novel class of driver mutations in human cancers and affect about 50% of Myelodysplastic syndrome (MDS) patients. Somatic mutations in MDS patients are frequently found in genes SF3B1, SRSF2, U2AF1, and ZRSR2. Interestingly, they are involved in the recognition of 3′ splice sites and exons. It has been reported that mutations in these splicing regulators result in aberrant splicing of many genes.
  • 2.2K
  • 12 Aug 2021
Topic Review
Slope Stability
The issue of slope stability is one of the most important and yet most difficult geotechnical problems. Assessing slope stability is particularly difficult because of the many uncertainties involved in the process. To take these uncertainties into account, probabilistic methods are used, and the reliability approach is adopted. There are many methods for reliability assessment of earth slope stability. However, there is no system that would organize all of these methods in an unambiguous way. In fact, these methods can be classified in different ways: by assignment to a deterministic classification of methods, by description of uncertainties of soil parameters, by level of reliability according to the theory of reliability, etc. The huge number of articles summarizing the research in this field, but in various “disordered” directions, certainly do not facilitate the understanding or ultimately the practical application of the reliability approach by the engineer. We propose a universal classification system of reliability methods for evaluating the stability of earth slopes. This proposal is preceded by a brief literature review of both historical background and contemporary study on reliability analysis of earth slope stability.
  • 2.2K
  • 17 Aug 2021
Topic Review
Selective Autophagy in Age-Associated Pathologies
Selective autophagy degrades a plethora of autophagic cargo, which is targeted upon specific cellular insults. Defective mitochondria (mitophagy), protein aggregates (aggrephagy) or pathogenic bacteria (xenophagy) are selective autophagy triggers. Atg8 proteins interact and recruit selective autophagic receptors, which contain LIR (LC3-interacting) motifs (W/F/Y-X-X-L/I/V), with upstream negatively charged residues for higher affinity interactions, as well as, post-translational modifications, such as phosphorylation.
  • 2.2K
  • 07 Sep 2021
Topic Review
Transthyretin
Transthyretin (TTR) is a thyroid hormone-binding protein which transports thyroxine from the bloodstream to the brain. The structural stability of TTR in tetrameric form is crucial for maintaining its original functions in blood or cerebrospinal fluid (CSF). The altered structure of TTR due to genetic mutations or its deposits due to aggregation could cause several deadly diseases such as cardiomyopathy and neuropathy in autonomic, motor, and sensory systems.
  • 2.2K
  • 03 Dec 2021
Topic Review
William Jennings Bryan Presidential Campaign, 1896
In 1896, William Jennings Bryan ran unsuccessfully for President of the United States. Bryan, a former Democratic congressman from Nebraska, gained his party's presidential nomination in July of that year after electrifying the Democratic National Convention with his Cross of Gold speech. He was defeated in the general election by the Republican candidate, former Ohio governor William McKinley. Born in 1860, Bryan grew up in rural Illinois and in 1887 moved to Nebraska, where he practiced law and entered politics. He won election to the House of Representatives in 1890, and was re-elected in 1892, before mounting an unsuccessful US Senate run. He set his sights on higher office, believing he could be elected president in 1896 even though he remained a relatively minor figure in the Democratic Party. In anticipation of a presidential campaign, he spent much of 1895 and early 1896 making speeches across the United States; his compelling oratory increased his popularity in his party. Bryan often spoke on the issue of the currency. The economic Panic of 1893 had left the nation in a deep recession, which still persisted in early 1896. Bryan and many other Democrats believed the economic malaise could be remedied through a return to bimetallism, or free silver—a policy they believed would inflate the currency and make it easier for debtors to repay loans. Bryan went to the Democratic convention in Chicago as an undeclared candidate, whom the press had given only a small chance of becoming the Democratic nominee. His 'Cross of Gold' speech, given to conclude the debate on the party platform, immediately transformed him into a favorite for the nomination, and he won it the next day. The Democrats nominated Arthur Sewall, a wealthy Maine banker and shipbuilder, for vice president. The left-wing Populist Party (which had hoped to nominate the only silver-supporting candidate) endorsed Bryan for president, but found Sewall unacceptable, substituting Thomas E. Watson of Georgia. Abandoned by many gold-supporting party leaders and newspapers after the Chicago convention, Bryan undertook an extensive tour by rail to bring his campaign to the people. He spoke some 600 times, to an estimated 5,000,000 listeners. His campaign focused on silver, an issue that failed to appeal to the urban voter, and he was defeated. The 1896 race is generally seen as a realigning election. The coalition of wealthy, middle-class and urban voters that defeated Bryan kept the Republicans in power for most of the time until 1932. Although defeated in the election, Bryan's campaign made him a national figure, which he remained until his death in 1925.
  • 2.2K
  • 26 Dec 2022
Topic Review
Lead–Acid Battery Faults
Lead–acid battery technology has been effectively fulfilling a variety of energy needs, ranging from classic car industry requirements to current plug-in hybrid electric vehicle requirements through any stationary system. Depending on the operating conditions, the battery can be affected in many ways. The same deterioration mechanisms affect all types of lead–acid batteries but to varying degrees. Two electrodes with the aqueous H2SO4 electrolyte (sulfuric acid) and the terminals are the main components of a lead–acid battery. A grid and the active material—PbO2 as the positive active material and Pb as the negative active material—make up the electrodes.
  • 2.2K
  • 05 Mar 2024
Topic Review
Heavy Metals in Medicinal Plants
It is possible for heavy metals (HMs) to be present in pharmaceutical herb materials coming from anthropogenic activities like agriculture, industrial waste, and natural sources. In various ethnic groups, there is evidence that contaminants were purposefully added in the belief that they had some sort of therapeutic benefit. HM toxicity of medicinal plant products has been linked to a wide range of adverse health effects, causing dysfunction of the liver, kidney, and heart, and even death.
  • 2.2K
  • 17 Feb 2023
Topic Review
Ecosystem Services Provided by Kelp Forests
Ecosystem services (ES) are defined as the benefits that humans obtain from ecological systems. These include services such as food and fresh water and climate regulation, among others that make human life possible. This concept is established as a “policy advocacy tool” since it helps with management practices. 
  • 2.2K
  • 14 Nov 2022
Topic Review
Standard and Alternative Cosmology
The Standard and The Alternative Cosmological Models, Distances Calculation to Galaxies without Hubble Constant For the alternative cosmological models considered in the extended version of this entry, the distances  are calculated for galaxies without using the Hubble constant. This process is mentioned in the second narrative, and described in detail in the third narration. According to the third narrative, as the density of the relativistic mass of the universe decreases while the universe expands, new matter is created by a phase transition process which results in a continuously constant ordinary density of matter. While the universe develops on the basis of this postulate of the emergence of new matter, it is "assumed that matter arises as a result of such a phase transition of dark energy into both new dark and visible matter. It is somewhat irrelevant how we describe dark energy, calling it aether, or vice versa, the changing of aether into dark energy. It should be clear to everyone that this renaming does not change the essence of this phase transition phenomena. It should be noted that, unlike all well‐known geometric models of the Euclidean space of our existence, this phase transition of dark energy into matter would accordingly be a stereographic projection of a three‐dimensional surface on to a four‐dimensional globe.
  • 2.2K
  • 29 Oct 2020
Topic Review
NMR in Milk Protein Structure
Milk proteins have a complex structure which changes as a result of applied treatment. The newly developed structural conformations of proteins exert influence on the quality of the final product. Structural characterization of milk proteins was successfully performed using NMR. This predominately refers to complete structural assignment on whey proteins and elucidation of sequential fragments of caseins.    As a non destructive method, NMR is a powerful tool which observe the nuclei of atoms immersed in large magnetic field producing radio sensitive signal. The produced signal gives information of the spatial orientation of the molecules and thus tertiary structure of proteins. 
  • 2.2K
  • 27 Oct 2020
Topic Review
Women of Color
Women of color (singular: woman of color, sometimes abbreviated as WOC) is a phrase used to describe female non-whites. The political term "women of color" surfaced in the violence against women movement. In the late seventies it unified all women experiencing multiple layers of marginalization with race or ethnicity as a common issue.
  • 2.2K
  • 17 Oct 2022
Topic Review
Kounotori Integrated Tether Experiment
Kounotori 6 (こうのとり6号機), also known as HTV-6, is the sixth flight of the H-II Transfer Vehicle, an uncrewed cargo spacecraft launched to resupply the International Space Station. It was launched at 13:26:47 UTC on 9 December 2016 aboard H-IIB launch vehicle from Tanegashima Space Center.
  • 2.2K
  • 27 Oct 2022
Topic Review
Radiometric Partial Discharge Detection
One of the most common failures or breakdowns that can occur in high-voltage (HV) equipment is due to partial discharges (PDs). This occurs as a result of inadequate insulation, aging, harsh environmental effects, or manufacturing flaws. PD detection and recognition methods have gained growing attention and have seen great progress in the past decades. Radiometric methods are one of the most investigated detection approaches due to their immunity to electromagnetic interference (EMI) and their capabilities to detect and locate PD activities in different applications such as transformers, cables, etc. 
  • 2.2K
  • 17 Mar 2023
Topic Review
GeForce 6 Series
The GeForce 6 series (codename NV40) is Nvidia's sixth generation of GeForce graphic processing units. Launched on April 14, 2004, the GeForce 6 family introduced PureVideo post-processing for video, SLI technology, and Shader Model 3.0 support (compliant with Microsoft DirectX 9.0c specification and OpenGL 2.0).
  • 2.2K
  • 21 Nov 2022
Topic Review
Curcuma longa L. Essential Oil
Curcuma longa L. rhizome essential oil is a valuable product in pharmaceutical industry due to its wide beneficial health effects.
  • 2.2K
  • 09 Feb 2021
Topic Review
Power Hardware-in-the-Loop (PHIL)
Power hardware-in-the-loop (PHIL) stands out as a strong testing solution, enabling a real-time simulated power system to be interfaced to hardware devices such as inverters to determine interactions between multiple inverters at multiple points of common coupling on the grid and microgrids. 
  • 2.2K
  • 18 Jan 2023
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