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Topic Review
SARS-CoV-2
In December of 2019, the first few cases of novel coronavirus-infected pneumonia were reported in Wuhan, China. Since then, in a series of novel reports, a research group from Nankai University of China (the Nankai group) presented several important findings of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2): (1) The alternative translations of Nankai CDS (a 465- or 468-bp genomic region) could produce more than 17 putative proteins of the betacoronavirus subgroup B (BB coronavirus); (2) A furin protease cleavage site (FCS) was discovered in the Spike (S) protein of SARS-CoV-2; (3) 5' UTR barcoding can be used for the detection, identification, classification and phylogenetic analysis of, but not limited to coronavirus; (4) The FCS in the SARS-CoV-2 genome was acquired through the combination of copy number variations of short tandem repeats and single nucleotide substitutions [4]; and (5) two criteria were proposed to determine the intermediate host(s).
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  • 13 Apr 2021
Topic Review
Flavonoids and Isoflavonoids Biosynthesis
Phenylpropanoid metabolism represents an important metabolic pathway from which originates a wide number of secondary metabolites derived from phenylalanine or tyrosine, such as flavonoids and isoflavonoids, crucial molecules in plants implicated in a large number of biological processes. Therefore, various types of interconnection exist between different aspects of nitrogen metabolism and the biosynthesis of these compounds. For legumes, flavonoids and isoflavonoids are postulated to play pivotal roles in adaptation to their biological environments, both as defensive compounds (phytoalexins) and as chemical signals in symbiotic nitrogen fixation with rhizobia. In this paper, we summarize the recent progress made in the characterization of flavonoid and isoflavonoid biosynthetic pathways in the model legume Lotus japonicus (Regel) Larsen under different abiotic stress situations, such as drought, the impairment of photorespiration and UV-B irradiation. Emphasis is placed on results obtained using photorespiratory mutants deficient in glutamine synthetase. The results provide different types of evidence showing that an enhancement of isoflavonoid compared to standard flavonol metabolism frequently occurs in Lotus under abiotic stress conditions. The advance produced in the analysis of isoflavonoid regulatory proteins by the use of co-expression networks, particularly MYB transcription factors, is also described. The results obtained in Lotus japonicus plants can be also extrapolated to other cultivated legume species, such as soybean, of extraordinary agronomic importance with a high impact in feeding, oil production and human health.
  • 2.5K
  • 20 Aug 2020
Topic Review
Bile Acids
Bile acids (BAs) are facial amphiphiles synthesized in the body of all vertebrates.
  • 2.5K
  • 18 Mar 2021
Topic Review
Portable Analytical Instruments in Mineral Exploration Studies
The classic approach to mineral exploration studies was to bring the field samples/drill cores collected during field studies to the laboratory, followed by laborious analysis procedures to generate the analytical data. This is very expensive, time-consuming, and difficult for exploring vast areas. However, rapid technological advances in field-portable analytical instruments, such as portable visible and near-infrared spectrophotometers, gamma-ray spectrometer, portable X-ray fluorescence spectrometers (pXRF), portable X-ray diffractometers (pXRD), portable laser-induced breakdown spectrometers (pLIBS), and µRaman spectrometer, have changed this scenario completely and increased their on-site applications in mineral exploration studies. LED fluorimeter is a potential portable tool in the hydrogeochemical prospecting studies of uranium. These instruments are currently providing direct, rapid, on-site, real-time, non-destructive, cost-effective identification, and determination of target elements, indicator minerals and pathfinder elements in rock, ore, soil, sediment, and water samples. These portable analytical instruments are currently helping to obtain accurate chemical and mineralogical information directly in the field with minimal or no sample preparation and providing decision-making support during fieldwork, as well as during drilling operations in several successful mineral exploration programs. 
  • 2.5K
  • 08 Apr 2022
Biography
Karl Jaspers
Karl Theodor Jaspers (/ˈjæspərz/; German: [ˈkaɐ̯l ˈjaspɐs];[1][2] 23 February 1883 – 26 February 1969) was a German-Swiss psychiatrist and philosopher who had a strong influence on modern theology, psychiatry, and philosophy. After being trained in and practicing psychiatry, Jaspers turned to philosophical inquiry and attempted to discover an innovative philosophical system. He was oft
  • 2.5K
  • 15 Nov 2022
Topic Review
Thin-Film Solar Cells
Due to the surge in silicon demand for solar modules, thin-film photovoltaic (PV) modules have a potential to penetrate the market in significant numbers. As an alternate candidate, thin film technologies in PVs have the ability to achieve better performance. The competing thin-film PV technologies have the flexibility to adapt to any sort of curvature compared to rigid solar cells (SCs). Due to the peculiar characteristics of newer solar materials, stability issues, reflection losses, advancements in electrode materials and dopant materials with a photoactive layer are current challenges driving the industrial-academic voyage of development of solar materials for the betterment of Photo-conversion Efficiency (PCE). Based on the photoactive materials used over time, SC evolution was broadly classified into first, second and third generation SCs.  
  • 2.5K
  • 25 Nov 2022
Topic Review
Teacher-Pupil Ethnicity Match and Achievement
In many countries, ethnic minority teachers are strongly underrepresented. It is often assumed that if there were more minority teachers, minority pupils would achieve much better. This assumption has rarely been empirically tested. In search of proof, the present study reviews the literature. 24 relevant studies were found, all pertaining to the US. The findings show that there is little empirical evidence that a stronger degree of ethnic match, be it in the form of a one-to-one coupling of teachers to pupils with the same ethnic background, or a larger share of minority teachers at an ethnically mixed school, leads to predominantly positive results. Insofar positive effects were found, they apply to a greater extent to subjective teacher evaluations than to objective achievement outcome measures.
  • 2.5K
  • 03 Nov 2020
Topic Review
Targeting hypoxia-driven metabolic reprogramming
Hypoxia-driven metabolic adaptation of cancer cells revolutionizes the current understanding of hypoxia-associated tumor development and progression. Several hypoxia-responsive molecular determinants, such as hypoxia-inducible factors, guide the cellular adaptation to hypoxia by gene activation, which is critical for promoting malignant progression in the hostile tumor microenvironment. This article fully recaps the major research progress in this topic in order to assess its potential as a targetable pathway to better combat cancer and overcome treatment resistance. Knowledge from this article facilitates cancer researchers to sharpen their focus on gaining mechanistic insights into metabolic transformation in hypoxic cancers and developing novel strategies to target tumor metabolic rewiring driven by hypoxia, which would open avenues to improve the management of tumor hypoxia.
  • 2.5K
  • 11 Aug 2020
Topic Review Peer Reviewed
Ionic Liquids in Drug Delivery
Ionic liquids (ILs) are molten salts composed of a large organic cation and an organic/inorganic anion. The large dimensions of their ions lead to charge dispersion, which makes difficult the formation of a regular crystalline structure. Due to their unique properties, ILs have been applied in the crystallization of active pharmaceutical ingredients (APIs), as solvents, co-solvents and emulsifiers in drug formulations, as pharmaceuticals (API-ILs) aiming liquid therapeutics, and in the development and/or improvement of drug-delivery-based systems.
  • 2.5K
  • 13 Apr 2022
Topic Review
Nonsense-Mediated mRNA Decay
Nonsense-mediated messenger RNA (mRNA) decay (NMD) is a surveillance pathway used by cells to control the quality mRNAs and to fine-tune transcript abundance. NMD plays an important role in cell cycle regulation, cell viability, DNA damage response, while also serving as a barrier to virus infection. Disturbance of this control mechanism caused by genetic mutations or dys-regulation of the NMD pathway can lead to pathologies, including neurological disorders, immune diseases and cancers. The role of NMD in cancer development is complex, acting as both a promoter and a barrier to tumour progression. Cancer cells can exploit NMD for the downregulation of key tumour suppressor genes, or tumours adjust NMD activity to adapt to an aggressive immune microenvironment.
  • 2.5K
  • 22 Sep 2021
Topic Review
Municipal Solid Waste Management in Beijing
An intelligent garbage sorting system (IGSS) is an effective sorting approach for MSW management. To explore the predictors of local residents’ willingness to pay (WTP) for the IGSS, this entry applied an extended theory of planned behavior (TPB) model by adding an antecedent environmental concern (EC) prior to the main predictors of the TPB model (attitudes, subject norms, perceived behavioral control). 
  • 2.5K
  • 20 Dec 2021
Topic Review
Three Vajras
The Three Vajras, namely "body, speech and mind", are a formulation within Vajrayana Buddhism and Bon that hold the full experience of the śūnyatā "emptiness" of Buddha-nature, void of all qualities (Wylie: yon tan) and marks (Wylie: mtshan dpe) and establish a sound experiential key upon the continuum of the path to enlightenment. The Three Vajras correspond to the trikaya and therefore also have correspondences to the Three Roots and other refuge formulas of Tibetan Buddhism. The Three Vajras are viewed in twilight language as a form of the Three Jewels, which imply purity of action, speech and thought. The Three Vajras are often mentioned in Vajrayana discourse, particularly in relation to samaya, the vows undertaken between a practitioner and their guru during empowerment. The term is also used during Anuttarayoga Tantra practice. In Tendai and Shingon Buddhism of Japan, they are known as the Three Mysteries (三密, sanmitsu).
  • 2.5K
  • 19 Oct 2022
Topic Review
Battle of Orgreave
The Battle of Orgreave was a violent confrontation on 18 June 1984 between pickets and officers of the South Yorkshire Police (SYP) and other police forces, including the Metropolitan Police, at a British Steel Corporation (BSC) coking plant at Orgreave, in Rotherham, South Yorkshire, England. It was a pivotal event in the 1984–1985 UK miners' strike, and one of the most violent clashes in British industrial history. Journalist Alastair Stewart has characterised it as "a defining and ghastly moment" that "changed, forever, the conduct of industrial relations and how this country functions as an economy and as a democracy". Most media reports at the time depicted it as "an act of self-defence by police who had come under attack". In 2015, the Independent Police Complaints Commission (IPCC) reported that there was "evidence of excessive violence by police officers, a false narrative from police exaggerating violence by miners, perjury by officers giving evidence to prosecute the arrested men, and an apparent cover-up of that perjury by senior officers". Historian Tristram Hunt has described the confrontation as "almost medieval in its choreography ... at various stages a siege, a battle, a chase, a rout and, finally, a brutal example of legalised state violence". 71 picketers were charged with riot and 24 with violent disorder. At the time, riot was punishable by life imprisonment. The trials collapsed when the evidence given by the police was deemed "unreliable". Gareth Peirce, who acted as solicitor for some of the pickets, said that the charge of riot had been used "to make a public example of people, as a device to assist in breaking the strike", while Michael Mansfield called it "the worst example of a mass frame-up in this country this century". In June 1991, the SYP paid £425,000 in compensation to 39 miners for assault, wrongful arrest, unlawful detention and malicious prosecution. Following the 2016 inquest verdict into the 1989 Hillsborough disaster, previously censored documents suggesting links between the actions of senior SYP officers at both incidents were published. This led to renewed calls for a public inquiry to be held into the actions of the police at Orgreave. In October 2016, in an Oral Answer to a Question in the House of Commons, a written ministerial statement to the House of Commons and Lords, and in a letter to the Orgreave Truth and Justice Campaign (OTJC), Home Secretary Amber Rudd announced there would be no statutory inquiry or independent review. In 2016, Alan Billings, the South Yorkshire Police and Crime Commissioner, admitted that the SYP had been "dangerously close to being used as an instrument of state". Despite the police evidence subsequently being deemed unreliable in court, there still exists a body of opinion that the police at Orgreave "were upholding the law in the face of intimidation from thousands of strikers".
  • 2.5K
  • 01 Nov 2022
Topic Review
Savoia-Marchetti SM.79
The Savoia-Marchetti SM.79 Sparviero (Italian for sparrowhawk) was a three-engined Italian medium bomber developed and manufactured by aviation company Savoia-Marchetti. It could be the best-known Italian aeroplane of the Second World War. The SM.79 was easily recognizable due to its distinctive fuselage dorsal "hump", and was reportedly well liked by its crews, who nicknamed it il gobbo maledetto ("damned hunchback"). The SM.79 had been originally developed during the early 1930s as a cantilever low-wing monoplane employing a combined wood-and-metal structure. It had been designed with the initial intention of producing a swift eight-passenger transport aircraft, capable of besting even the fastest of its contemporaries at that time, however, the project quickly attracted the attention of the Italian government for its potential as an armed combat aircraft. Performing its first flight on 28 September 1934; between 1937 and 1939, early examples of the type established 26 separate world records, qualifying it for some time as being the fastest medium bomber in the world. As such, the SM.79 quickly became regarded as an item of national prestige in Fascist Italy, attracting significant government support and often being deployed as an element of state propaganda. Early on, the aircraft was routinely entered into competitive fly-offs and air races, seeking to capitalise on its advantages, and often emerged victorious in such contests. The SM.79 first saw combat during the Spanish Civil War; in this theatre, it operated without fighter escorts, normally relying on its relatively high speed to evade interception instead. While some issues were identified, and in some cases resolved, the SM.79's performance during the Spanish deployment was encouraging and stimulated demand for the type, including a decision to adopt it as the backbone of Italy's bomber units. Both Yugoslavia and Romania opted to procure the type for their own air services, while large numbers were also procured for the Regia Aeronautica. Almost 600 SM.79-I and –II aircraft were in service when Italy entered the Second World War during May 1940; thereafter, these aircraft were deployed across every theatre of war in which the Italians fought. The SM.79 was operated in various different capacities during the Second World War; initially, the type was used as a transport aircraft and medium bomber. Following pioneering work by the "Special Aerotorpedoes Unit", Italy put the type to work as a torpedo bomber; in this role, the SM.79 achieved notable successes against Allied shipping, particularly in the Mediterranean theater. A specialised drone version of the aircraft, flown by remote control was also developed, although the Armistice with Italy was enacted prior to any operational deployment. It was the most numerous Italian bomber of the Second World War, around some 1,300 aircraft were constructed. The type would remain in Italian service until 1952.
  • 2.5K
  • 30 Nov 2022
Topic Review
Sustainable Exploitation of Posidonia oceanica Sea Balls (Egagropili)
Posidonia oceanica (L.) Delile is the main seagrass plant in the Mediterranean basin that forms huge underwater meadows. Its leaves, when decomposed, are transported to the coasts, where they create huge banquettes that protect the beaches from sea erosion. Its roots and rhizome fragments, instead, aggregate into fibrous sea balls, called egagropili, that are shaped and accumulated by the waves along the shoreline. Their presence on the beach is generally disliked by tourists, and, thus, local communities commonly treat them as waste to remove and discard. Posidonia oceanica egagropili might represent a vegetable lignocellulose biomass to be valorized as a renewable substrate to produce added value molecules in biotechnological processes, as bio-absorbents in environmental decontamination, to prepare new bioplastics and biocomposites, or as insulating and reinforcement materials for construction and building.
  • 2.5K
  • 23 Apr 2023
Topic Review
The Role of Small Molecules Containing Fluorine Atoms
The fluorine atom possesses many intrinsic properties that can be beneficial when incorporated into small molecules. These properties include the atom’s size, electronegativity, and ability to block metabolic oxidation sites. Substituents that feature fluorine and fluorine-containing groups are currently prevalent in drugs that lower cholesterol, relieve asthma, and treat anxiety disorders, as well as improve the chemical properties of various medications and imaging agents. 
  • 2.5K
  • 27 Feb 2024
Topic Review
Antidepressants and Circadian Rhythm
Circadian oscillations alter drug absorption, distribution, metabolism, and excretion (ADME) as well as intracellular signaling systems, target molecules (e.g., receptors, transporters, and enzymes), and gene transcription. There is a positive influence of drug dosing-time on the efficacy of depression therapy. On the other hand, antidepressants have also demonstrated to modulate circadian rhythmicity and sleep–wake cycles. 
  • 2.5K
  • 23 Dec 2021
Topic Review
Compounds of Thorium
Many compounds of thorium are known, this is because thorium and uranium are the most stable and accessible actinides and are the only actinides that can be studied safely and legally in bulk in a normal laboratory. As such, they have the best-known chemistry of the actinides, along with that of plutonium, as the self-heating and radiation from them is not enough to cause radiolysis of chemical bonds as it is for the other actinides. While the later actinides from americium onwards are predominantly trivalent and behave more similarly to the corresponding lanthanides, as one would expect from periodic trends, the early actinides up to plutonium (thus including thorium and uranium) have relativistically destabilised and hence delocalised 5f and 6d electrons that participate in chemistry in a similar way to the early transition metals of group 3 through 8: thus, all their valence electrons can participate in chemical reactions, although this is not common for neptunium and plutonium.
  • 2.5K
  • 25 Oct 2022
Topic Review
Covalent Inhibitors Covalently Bound to Cysteine
Covalent inhibitors are a class of small molecule compounds that can covalently bind to specific target proteins, thereby inhibiting their biological functions. Cysteine is one of the least abundant amino acids in proteins of many organisms, which plays a crucial role in catalysis, signal transduction, and redox regulation of gene expression. The thiol group of cysteine possesses the ability to perform nucleophilic and redox-active functions that are not feasible for other natural amino acids. Cysteine is the most common covalent amino acid residue and has been shown to react with a variety of warheads, especially Michael receptors.
  • 2.5K
  • 18 Nov 2022
Biography
Roy Spencer
Roy Warren Spencer (born December 20, 1955)[1] is a meteorologist,[2] a principal research scientist at the University of Alabama in Huntsville, and the U.S. Science Team leader for the Advanced Microwave Scanning Radiometer (AMSR-E) on NASA's Aqua satellite.[3][4] He has served as senior scientist for climate studies at NASA's Marshall Space Flight Center.[3][4] He is known for his satellite-b
  • 2.5K
  • 06 Dec 2022
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