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Topic Review
Mechanisms of CYP450 Inhibition
In an ageing society, polypharmacy has become a major public health and economic issue. Overuse of medications, especially in patients with chronic diseases, carries major health risks. One common consequence of polypharmacy is the increased emergence of adverse drug events, mainly from drug–drug interactions. The majority of currently available drugs are metabolized by CYP450 enzymes. Interactions due to shared CYP450-mediated metabolic pathways for two or more drugs are frequent, especially through reversible or irreversible CYP450 inhibition. The magnitude of these interactions depends on several factors, including varying affinity and concentration of substrates, time delay between the administration of the drugs, and mechanisms of CYP450 inhibition. Various types of CYP450 inhibition (competitive, non-competitive, mechanism-based) have been observed clinically, and interactions of these types require a distinct clinical management strategy.
  • 2.9K
  • 17 May 2021
Topic Review
Arbutin
Arbutin is a compound with a structure in which one molecule of D-glucose is bound to hydroquinone.
  • 2.9K
  • 18 Aug 2021
Topic Review
Water Resource Management
Water resource management is the activity of planning, developing, distributing and managing the optimum use of water resources. It is an aspect of water cycle management. Water is essential for our survival. The field of water resources management will have to continue to adapt to the current and future issues facing the allocation of water. With the growing uncertainties of global climate change and the long-term impacts of past management actions, this decision-making will be even more difficult. It is likely that ongoing climate change will lead to situations that have not been encountered. As a result, alternative management strategies, including participatory approaches and adaptive capacity are increasingly being used to strengthen water decision-making. Ideally, water resource management planning has regard to all the competing demands for water and seeks to allocate water on an equitable basis to satisfy all uses and demands. As with other resource management, this is rarely possible in practice so decision-makers must prioritise issues of sustainability, equity and factor optimisation (in that order!) to achieve acceptable outcomes. One of the biggest concerns for our water-based resources in the future is the sustainability of the current and future water resource allocation. As water becomes scarce, the importance of water management grows vastly—finding a balance between humans' needs and the essential step of water resources sustainability in the environment.
  • 2.9K
  • 03 Nov 2022
Topic Review
LiDAR-Derived DEM in Flood Applications
Flood occurrence is increasing due to escalated urbanization and extreme climate change; hence, various studies on this issue and methods of flood monitoring and mapping are also increasing to reduce the severe impacts of flood disasters. The advancement of current technologies such as light detection and ranging (LiDAR) systems facilitated and improved flood applications. Since the conventional methods cannot produce high-resolution digital elevation model (DEM) data, which results in low accuracy of flood simulation results, LiDAR data are extensively used as an alternative. This review aims to study the potential and the applications relevant to flood studies from a LiDAR-derived DEM perspective. It also provides insight into the operating principles of different LiDAR systems, system components, and advantages and disadvantages of each system. Furthermore, the challenges and future perspectives regarding DEM LiDAR data for flood mapping and assessment are also discussed. This study demonstrates that LiDAR-derived data are useful in flood risk management, especially in the future assessment of flood-related problems.  
  • 2.9K
  • 04 Aug 2020
Topic Review
Antimicrobial Blue Light
Blue light primarily exhibits antimicrobial activity through the activation of endogenous photosensitizers, which leads to the formation of reactive oxygen species that attack components of bacterial cells, such as cell wall, cell membrane and genome. Current data show that blue light is innocuous on the skin, but may inflict photo-damage to the eyes. While complete resistance to blue light has not been reported, isolated evidence suggests that bacterial tolerance to blue light may occur over time, especially through gene mutations, although at a slower rate than antibiotic resistance. Future studies can aim at characterizing the amount and type of intracellular photosensitizers across bacterial species and at assessing the oxygen-independent mechanism of blue light.
  • 2.9K
  • 11 Jan 2021
Topic Review
Nitric Oxide Synthase
Nitric oxide synthase (NOS) plays important roles within the cardiovascular system in physiological states as well as in pathophysiologic and specific cardiovascular (CV) disease states, such as hypertension (HTN), arteriosclerosis, and cerebrovascular accidents.
  • 2.9K
  • 07 May 2022
Topic Review
Reflective Façades
Reflection and transparency are two valuable properties associated with the use of glass as an architectural material. While proponents of modernism favored transparency over reflection, whether in its physical or conceptual implications, to justify the designs of façades of Modernist buildings and in architectural criticism, contemporary architects are revisiting the neglected trait of ‘reflection’.
  • 2.9K
  • 14 Nov 2023
Topic Review
Resistance in Powdery Mildew Fungi
Powdery mildew fungi (Erysiphales) are among the most common and important plant fungal pathogens. These fungi are obligate biotrophic parasites that attack nearly 10,000 species of angiosperms, including major crops, such as cereals and grapes. Although cultural and biological practices may reduce the risk of infection by powdery mildew, they do not provide sufficient protection. Therefore, in practice, chemical control, including the use of fungicides from multiple chemical groups, is the most effective tool for managing powdery mildew. Unfortunately, the risk of resistance development is high because typical spray programs include multiple applications per season. In addition, some of the most economically destructive species of powdery mildew fungi are considered to be high-risk pathogens and are able to develop resistance to several chemical classes within a few years. This situation has decreased the efficacy of the major fungicide classes, such as sterol demethylation inhibitors, quinone outside inhibitors and succinate dehydrogenase inhibitors, that are employed against powdery mildews.
  • 2.9K
  • 25 Sep 2020
Topic Review
HIV-1 Capsid Protein
The capsid (CA) protein of the human immunodeficiency virus type 1 (HIV-1) is an essential structural component of a virion and facilitates many crucial life cycle steps through interactions with host cell factors. Capsid shields the reverse transcription complex from restriction factors while it enables trafficking to the nucleus by hijacking various adaptor proteins, such as FEZ1 and BICD2. In addition, the capsid facilitates the import and localization of the viral complex in the nucleus through interaction with NUP153, NUP358, TNPO3, and CPSF-6. In the later stages of the HIV-1 life cycle, CA plays an essential role in the maturation step as a constituent of the Gag polyprotein. In the final phase of maturation, Gag is cleaved, and CA is released, allowing for the assembly of CA into a fullerene cone, known as the capsid core. The fullerene cone consists of ~250 CA hexamers and 12 CA pentamers and encloses the viral genome and other essential viral proteins for the next round of infection. As research continues to elucidate the role of CA in the HIV-1 life cycle and the importance of the capsid protein becomes more apparent, CA displays potential as a therapeutic target for the development of HIV-1 inhibitors.
  • 2.9K
  • 20 Feb 2021
Topic Review
Ruby Pistol
The self-loading Ruby pistol is best known as a French World War I sidearm, the Pistolet Automatique de 7 millim.65 genre "Ruby". A very international piece of weaponry, it was closely modeled after John Browning's M1903 design produced by the Belgian Fabrique Nationale de Herstal, and was produced by over 50 Spanish companies, but primarily by the Spanish Gabilondo y Urresti firm (the official "Gabilondo Ruby"). It was decommissioned in 1958, more than a decade after World War II was brought to an end, and was subsequently replaced.
  • 2.9K
  • 20 Oct 2022
Topic Review
Bioglass
Bioglass 45S5, commonly referred to by its commercial name Bioglass, is a glass specifically composed of 45 wt% SiO2, 24.5 wt% CaO, 24.5 wt% Na2O, and 6.0 wt% P2O5.  Glasses are non-crystalline amorphous solids that are commonly composed of silica-based materials with other minor additives.  Compared to soda-lime glass (commonly used, as in windows or bottles), Bioglass 45S5 contains less silica and higher amounts of calcium and phosphorus.  The 45S5 name signifies glass with 45 weight % of SiO2 and 5:1 molar ratio of calcium to phosphorus.  This high ratio of calcium to phosphorus promotes formation of apatite crystals; calcium and silica ions can act as crystallization nuclei.  Lower Ca:P ratios do not bond to bone.  Bioglass 45S5's specific composition is optimal in biomedical applications because of its similar composition to that of hydroxyapatite, the mineral component of bone. This similarity provides Bioglass' ability to be integrated with living bone. This composition of bioactive glass is comparatively soft in comparison to other glasses. It can be machined, preferably with diamond tools, or ground to powder. Bioglass has to be stored in a dry environment, as it readily absorbs moisture and reacts with it. Bioglass 45S5 is the first formulation of an artificial material that was found to chemically bond with bone. One of its main medical advantages is its biocompatibility, seen in its ability to avoid an immune reaction and fibrous encapsulation. Its primary application is the repair of bone injuries or defects too large to be regenerated by the natural process. The first successful surgical use of Bioglass 45S5 was in replacement of ossicles in the middle ear, as a treatment of conductive hearing loss. Other uses include cones for implantation into the jaw following a tooth extraction. Composite materials made of Bioglass 45S5 and patient's own bone can be used for bone reconstruction. Further research is being conducted for the development of new processing techniques to allow for more applications of Bioglass.
  • 2.9K
  • 01 Nov 2022
Topic Review
Electrodermal Activity Data Collection
The electrodermal activity (EDA) signal is an electrical manifestation of the sympathetic innervation of the sweat glands. EDA has a history in psychophysiological (including emotional or cognitive stress) research since 1879, but it was not until recent years that researchers began using EDA for pathophysiological applications like the assessment of fatigue, pain, sleepiness, exercise recovery, diagnosis of epilepsy, neuropathies, depression, and so forth. The advent of new devices and applications for EDA has increased the development of novel signal processing techniques, creating a growing pool of measures derived mathematically from the EDA. For many years, simply computing the mean of EDA values over a period was used to assess arousal. Much later, researchers found that EDA contains information not only in the slow changes (tonic component) that the mean value represents, but also in the rapid or phasic changes of the signal. The techniques that have ensued have intended to provide a more sophisticated analysis of EDA, beyond the traditional tonic/phasic decomposition of the signal. With many researchers from the social sciences, engineering, medicine, and other areas recently working with EDA, it is timely to summarize and review the recent developments and provide an updated and synthesized framework for all researchers interested in incorporating EDA into their research.
  • 2.9K
  • 30 Oct 2020
Topic Review
Information Exactly Defined
This review focuses the exact and global definition of information (for unambiguous interpretation as mathematical object) and its digital application. New uniformly defined "domain vectors" (DVs), with structure "UL plus number sequence", are proposed. The "UL" is an efficient global pointer to the uniform online definition of the (after the UL) following number sequence. DVs are globally exactly defined, identified, interoperable, comparable, and (language independently) searchable by criteria which users can define online. The introduction of a compact DV data structure may substantially improve the digital representation of information.
  • 2.9K
  • 11 Apr 2021
Topic Review
Hesperidin and SARS-CoV-2
Among the flavonoids, hesperidin has recently attracted the attention of researchers, because it binds to the key proteins of the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Several computational methods, independently applied by different researchers, showed that hesperidin has a low binding energy, both with the coronavirus “spike” protein, and with the main protease that transforms the early proteins of the virus into the complex responsible for viral replication. The binding energy of hesperidin to these important components is lower than that of lopinavir, ritonavir, and indinavir, suggesting that it could perform an effective antiviral action. Furthermore, both hesperidin and ascorbic acid counteract the cell damaging effects of the oxygen free radicals triggered by virus infection and inflammation.
  • 2.9K
  • 26 Oct 2020
Topic Review
Declaration of Nullity
Template:Canon Law In the Catholic Church, a declaration of nullity, commonly called an annulment and less commonly a decree of nullity, is a judgment on the part of an ecclesiastical tribunal determining that a marriage was invalidly contracted or, less frequently, a judgment determining that ordination was invalidly conferred. A matrimonial nullity trial, governed by canon law, is a judicial process whereby a canonical tribunal determines whether the marriage was void at its inception (ab initio). A "Declaration of Nullity" is not the dissolution of an existing marriage (as is a dispensation from a marriage ratum sed non consummatum and an "annulment" in civil law), but rather a determination that consent was never validly exchanged due to a failure to meet the requirements to enter validly into matrimony and thus a marriage never existed. The Catholic Church teaches that, in a true marriage, one man and one woman become "one flesh" before the eyes of God. Various impediments can render a person unable to validly contract a marriage. Besides impediments, marriage consent can be rendered null due to invalidating factors such as simulation or deceit, or to psychological incapacity. In 2015, the process for declaring matrimonial nullity was amended by the matrimonial nullity trial reforms of Pope Francis, the broadest reforms to matrimonial nullity law in 300 years. Prior to the reforms, a declaration of nullity could only be effective if it had been so declared by two tribunals at different levels of jurisdiction. If the lower courts (First and Second Instance) were not in agreement, the case went automatically to the Roman Rota for final decision one way or another.
  • 2.9K
  • 09 Oct 2022
Topic Review
Grihastha
Grihastha (Sanskrit: gr̥hastha) literally means "being in and occupied with home, family" or "householder". It refers to the second phase of an individual's life in a four age-based stages of the Hindu ashram system. It follows celibacy (bachelor student) life stage, and embodies a married life, with the duties of maintaining a home, raising a family, educating one's children, and leading a family-centred and a dharmic social life. This stage of Ashrama is conceptually followed by Vanaprastha (forest dweller, retired) and Sannyasa (renunciation). Combined with other three life stages, Hindu philosophy considers these stages as a facet of Dharma concept, something essential to completing the full development of a human being and fulfilling all the needs of the individual and society. Ancient and medieval era texts of Hinduism consider Grihastha stage as the most important of all stages in sociological context, as human beings in this stage not only pursue a virtuous life, they produce food and wealth that sustains people in other stages of life, as well as the offspring that continues mankind. The householder stage is also considered in Indian philosophy as one where the most intense physical, sexual, emotional, occupational, social and material attachments exist in a human being's life. In Indian traditions, Grihastha stage of life is a recommendation, but not a requirement. Any Brahmacharya may, if he or she wants, skip householder and retirement stage, go straight to Sannyasa stage of life, thereby renouncing worldly and materialistic pursuits and dedicating their lives to spiritual pursuits.
  • 2.9K
  • 11 Oct 2022
Topic Review
Yellow Supergiant Star
A yellow supergiant (YSG) is a star, generally of spectral type F or G, having a supergiant luminosity class (e.g. Ia or Ib). They are stars that have evolved away from the main sequence, expanding and becoming more luminous. Yellow supergiants are smaller than red supergiants; naked eye examples include Polaris. Many of them are variable stars, mostly pulsating Cepheids such as δ Cephei itself.
  • 2.9K
  • 03 Nov 2022
Topic Review
Triceratops Obtusus
Triceratops (/traɪˈsɛrəˌtɒps/ trahy-ser-uh-tops; lit. three-horned face) is a genus of herbivorous chasmosaurine ceratopsid dinosaur that first appeared during the late Maastrichtian stage of the Late Cretaceous period, about 68 million years ago in what is now North America. It is one of the last-known non-avian dinosaur genera, and became extinct in the Cretaceous–Paleogene extinction event 66 million years ago. The name Triceratops, which literally means 'three-horned face', is derived from the Greek words trí- (τρί-) meaning 'three', kéras (κέρας) meaning 'horn', and ṓps (ὤψ) meaning 'face'. Bearing a large bony frill, three horns on the skull, and a large four-legged body, exhibiting convergent evolution with rhinoceroses and bovines, Triceratops is one of the most recognizable of all dinosaurs and the most well-known ceratopsid. It was also one of the largest, up to 8–9 metres (26–30 ft) long and 5–9 metric tons (5.5–9.9 short tons) in body mass. It shared the landscape with and was most likely preyed upon by Tyrannosaurus, though it is less certain that two adults did battle in the fanciful manner often depicted in museum displays and popular images. The functions of the frills and three distinctive facial horns on its head have long inspired debate. Traditionally, these have been viewed as defensive weapons against predators. More recent interpretations find it probable that these features were primarily used in species identification, courtship, and dominance display, much like the antlers and horns of modern ungulates. Triceratops was traditionally placed within the "short-frilled" ceratopsids, but modern cladistic studies show it to be a member of the Chasmosaurinae which usually have long frills. Two species, T. horridus and T. prorsus, are considered valid today, from the seventeen species that have ever been named. Research published in 2010 concluded that the contemporaneous Torosaurus, a ceratopsid long regarded as a separate genus, represents Triceratops in its mature form. This view has been disputed; further data is needed to settle the debate. Triceratops has been documented by numerous remains collected since the genus was first described in 1889 by American paleontologist Othniel Charles Marsh. Specimens representing life stages from hatchling to adult have been found. As the archetypal ceratopsid, Triceratops is one of the most popular dinosaurs, and has been featured in film, postal stamps, and many other types of media.
  • 2.9K
  • 17 Nov 2022
Topic Review
Structure and Function of FSP1
Ferroptosis suppressor protein 1 (FSP1), an NAD(P)H-ubiquinone oxidoreductase that reduces ubiquinone to ubiquinol, has emerged as a critical player in the regulation of ferroptosis. FSP1 operates independently of the canonical system xc–/glutathione peroxidase 4 pathway, making it a promising target for inducing ferroptosis in cancer cells and overcoming ferroptosis resistance.
  • 2.9K
  • 14 Jun 2023
Topic Review
Pharmacological Effects of Houttuynia cordata Thunb (H. cordata)
Houttuynia cordata Thunb (H. cordata) is a rhizomatous, herbaceous, and perennial plant widely distributed in Asia. It has multiple chemical constituents, such as alkaloids, essential oils, phenolic acids, and flavonoids used against various health problems. The essential oils and flavonoids are the main components of H. cordata that play an essential role in disease treatment and traditional health care. Moreover, the leaves and stems of H. cordata have a long medicinal history in China. In addition, H. cordata is used against several health issues, such as cold, cough, fever, pneumonia, mumps, and tumors, due to its anti-inflammatory, anti-bacterial, anti-viral, anti-oxidant, and anti-tumor effects.
  • 2.9K
  • 07 Sep 2022
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