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Topic Review
Water Stress and Water Footprint
Physical water stress and scarcity are often used interchangeably, or the exact nature of the underlying data is not clearly defined or justified (e.g., water use versus consumption versus withdrawal). A number of authors have noted that there is no widely accepted definition for physical water stress and scarcity.   Comparing different definitions of water stress and scarcity, they seem to be converging on the definition given by the CEO Water Mandate (A NGO affiliated with the United Nations), who defines water scarcity as lack of physical abundance of freshwater resources without considering whether water is suitable for use, and water stress as lack of ability to meet human and ecological demand for freshwater, in terms of water quantity and quality and accessibility to water.
  • 1.4K
  • 01 Feb 2022
Topic Review
Proton Transport Chain
Carboxylic acids dissociate in water to carboxylates (R-COO-) and oxonium (H+[H2O]n) ions. The Proton Transport Chain (PTC) hypothesis asserts that enzyme complexes bridge nascent acids and ensure water-free transfer of the intermediate substrate. The PTC hypothesis entails that the concentration of the transferred acid is mathematically infinite and an infinite concentration drives enzymatic reactions unidirectionally. In support of this, a number of enzymes, such as proton-linked monocarboxylate transporters (MCTs), lactate dehydrogenases (LDHs) or sodium/hydrogen exchangers have been experimentally determined to catalyse unidirectionally. In addition, enzyme complexes, such as the pyruvate dehydrogenase complex (PDHc), are also known to catalyse unidirectionally. Scientific concepts, such as the original Citric Acid Cycle proposed that acids are metabolized in a clockwise direction. The PTC hypothesis provides mechanisms, mathematics and law of nature for biological processes.
  • 1.4K
  • 26 Feb 2021
Topic Review
Antimicrobial Resistance of VBNC Bacteria
 Antimicrobial Resistance of VBNC Bacteria means the bacteria that enter the viable but non-culturable (VBNC) state, either through unfavorable environmental conditions or through potentially lethal stress, lose their ability to grow on standard enrichment media, but show a drastically increased tolerance against antimicrobials including antibiotics.
  • 1.4K
  • 16 Feb 2021
Topic Review
Pruritus Pathogenesis in Psoriasis
Psoriasis is a chronic, systemic inflammatory disease with a genetic background that involves almost 3% of the general population worldwide. About 70-80% of psoriatic patients suffer from pruritus. Despite its high prevalence in psoriasis, its pathogenesis still remains unclear. 
  • 1.4K
  • 22 Sep 2021
Topic Review
Nuclear Factor Kappa B
NF-κB is a family of five eukaryotic transcription factors, p50, p52, p65 (RelA), RelB and c-Rel, which form 15 different homodimers and heterodimers.
  • 1.4K
  • 09 May 2021
Topic Review
HBVcccDNA
Hepatitis B virus (HBV) remains a major public health concern, with more than 250 million chronically infected people who are at high risk of developing liver diseases, including cirrhosis and hepatocellular carcinoma. Although antiviral treatments efficiently control virus replication and improve liver function, they cannot cure HBV infection. Viral persistence is due to the maintenance of the viral circular episomal DNA, called covalently closed circular DNA (cccDNA), in the nuclei of infected cells. cccDNA not only resists antiviral therapies, but also escapes innate antiviral surveillance. This viral DNA intermediate plays a central role in HBV replication, as cccDNA is the template for the transcription of all viral RNAs, including pregenomic RNA (pgRNA), which in turn feeds the formation of cccDNA through a step of reverse transcription. The establishment and/or expression of cccDNA is thus a prime target for the eradication of HBV.
  • 1.4K
  • 27 May 2021
Topic Review
Aβ-Peptide Production and Conformational Behavior
Alzheimer’s disease  (AD) is the most common type of neurodegenerative disease in the world. Genetic evidence strongly suggests that aberrant generation, aggregation, and/or clearance of neurotoxic amyloid-β peptides (Aβ) triggers the disease. Aβ accumulates at the points of contact of neurons in ordered cords and fibrils, forming the so-called senile plaques. Aβ isoforms of different lengths are found in healthy human brains regardless of age and appear to play a role in signaling pathways in the brain and to have neuroprotective properties at low concentrations. This entry describes molecular mechanisms of amyloid-β precursor protein processing in AD.
  • 1.4K
  • 11 Oct 2021
Topic Review
Polyphenols and Neuroprotection
Polyphenols are naturally occurring micronutrients that are present in many food sources. Besides being potent antioxidants, these molecules may also possess anti-inflammatory properties. Many studies have highlighted their potential role in the prevention and treatment of various pathological conditions connected to oxidative stress and inflammation (e.g., cancer, and cardiovascular and neurodegenerative disorders). Neurodegenerative diseases are globally one of the main causes of death and represent an enormous burden in terms of human suffering, social distress, and economic costs. Recent data expanded on the initial antioxidant-based mechanism of polyphenols’ action by showing that they are also able to modulate several cell-signaling pathways and mediators. The proposed benefits of polyphenols, either as protective/prophylactic substances or as therapeutic molecules, may be achieved by the consumption of a natural polyphenol-enriched diet, by their use as food supplements, or with formulations as pharmaceutical drugs/nutraceuticals.
  • 1.4K
  • 15 Jun 2021
Topic Review
Kaolinitic Raw Materials for Ceramics
Eight kaolinitic materials from the Lokoundje River at Kribi were sampled and investigated for their physical, chemical, mineralogical and thermal characteristics in order to evaluate their potential suitability as raw materials in ceramics. The Lokoundje kaolinitic materials are clayey to silty clayey and are predominantly composed of kaolinite and quartz. The alkali (Na2O + K2O) content ranges between 1 and 2.5 wt.%; these low values do not favor vitrification of the ceramics but may be improved through flux amendment. The presence of goethite in some samples limits their utilization in white ceramics. The minerals content, color, metallic sound, cohesion, linear shrinkage, flexural strength, bulk density, water absorption and microstructure were determined. The XRD data reveal that kaolinite and goethite were transformed, respectively, into mullite and hematite. The colors of the fired products are characteristic of their mineral assemblage. The metallic sound is indicative of low vitrification which is confirmed by the presence of cracks due to low flux contents. The cohesion is good to very good, due to the abundance of kaolinite. The physicomechanical properties increase with temperature as well as densification. The geochemical data show that the Lokoundje alluvial clays are suitable for the manufacture of white stoneware tiles. 
  • 1.4K
  • 09 Jul 2021
Topic Review
Therapeutic Approaches Utilizing Macrophage-Derived iNOS/NO in Cancer
Nitric oxide and its production by iNOS is an established mechanism critical to tumor promotion or suppression. Macrophages have important roles in immunity, development, and progression of cancer and have a controversial role in pro-and anti-tumoral effects. The tumor microenvironment consists of tumor-associated macrophages (TAM), among other cell types that influence the fate of the growing tumor. Depending on the microenvironment and various cues, macrophages polarize into a continuum represented by the M1-like pro-inflammatory phenotype or the anti-inflammatory M2-like phenotype; these two are predominant, while there are subsets and intermediates. Manipulating their plasticity through programming or reprogramming of M2-like to M1-like phenotypes presents the opportunity to maximize tumoricidal defenses. The dual role of iNOS derived NO also influences TAM activity by repolarization to tumoricidal M1-type phenotype. Regulatory pathways and immunomodulation achieve this through miRNA that may inhibit the immunosuppressive tumor microenvironment.
  • 1.4K
  • 07 Dec 2021
Topic Review
Mechanisms of Kidney Damage in Acute Hepatic Porphyrias
Porphyrias are a group of rare disorders originating from an enzyme dysfunction in the pathway of heme biosynthesis. Depending on the specific enzyme involved, porphyrias manifest under drastically different clinical pictures. The most dramatic presentation of the four congenital acute hepatic porphyrias (AHPs: acute intermittent porphyria—AIP, ALAD deficiency, hereditary coproporphyria—HCP, and porphyria variegata—VP) consists of potentially life-threatening neurovisceral attacks, for which givosiran, a novel and effective siRNA-based therapeutic, has recently been licensed. Nonetheless, the clinical manifestations of acute porphyrias are multifaceted and do not limit themselves to acute attacks. In particular, porphyria-associated kidney disease (PAKD) is a distinct, long-term degenerating condition with specific pathological and clinical features, for which a satisfactory treatment is not available yet. In PAKD, chronic tubule-interstitial damage has been most commonly reported, though other pathologic features (e.g., chronic fibrous intimal hyperplasia) are consistent findings. Given the relevant role of the kidney in porphyrin metabolism, the mechanisms possibly intervening in causing renal damage in AHPs are different: among others, δ-aminolevulinic acid (ALA)-induced oxidative damage on mitochondria, intracellular toxic aggregation of porphyrins in proximal tubular cells, and derangements in the delicate microcirculatory balances of the kidney might be implicated. The presence of a variant of the human peptide transporter 2 (PEPT2), with a greater affinity to its substrates (including ALA), might confer a greater susceptibility to kidney damage in patients with AHPs. Furthermore, a possible effect of givosiran in worsening kidney function has been observed. In sum, the diagnostic workup of AHPs should always include a baseline evaluation of renal function, and periodic monitoring of the progression of kidney disease in patients with AHPs is strongly recommended.
  • 1.4K
  • 07 Feb 2022
Topic Review
Open Software License
The Open Software License (OSL) is a software license created by Lawrence Rosen. The Open Source Initiative (OSI) has certified it as an open-source license, but the Debian project judged version 1.1 to be incompatible with the DFSG. The OSL is a copyleft license, with a termination clause triggered by filing a lawsuit alleging patent infringement. Many people in the free software and open-source community feel that software patents are harmful to software, and are particularly harmful to open-source software. The OSL attempts to counteract that by creating a pool of software which a user can use if that user does not harm it by attacking it with a patent lawsuit.
  • 1.4K
  • 27 Sep 2022
Topic Review
Sex Differences in Memory
Although there are many physiological and psychological gender differences in humans, memory, in general, is fairly stable across the sexes. By studying the specific instances in which males and females demonstrate differences in memory, we are able to further understand the brain structures and functions associated with memory. It is within specific experimental trials that differences appear, such as methods of recalling past events, explicit facial emotion recognition tasks, and neuroimaging studies regarding size and activation of different brain regions. Research seems to focus especially on gender differences in explicit memory. Like many other nuances of the human psyche, these differences are studied with the goal of lending insight to a greater understanding of the human brain.
  • 1.4K
  • 10 Oct 2022
Topic Review
Windows Service
In Windows NT operating systems, a Windows service is a computer program that operates in the background. It is similar in concept to a Unix daemon. A Windows service must conform to the interface rules and protocols of the Service Control Manager, the component responsible for managing Windows services. It is the Services and Controller app, services.exe, that launches all the services and manages their actions, such as start, end, etc. Windows services can be configured to start when the operating system is started and run in the background as long as Windows is running. Alternatively, they can be started manually or by an event. Windows NT operating systems include numerous services which run in context of three user accounts: System, Network Service and Local Service. These Windows components are often associated with Host Process for Windows Services. Because Windows services operate in the context of their own dedicated user accounts, they can operate when a user is not logged on. Prior to Windows Vista, services installed as an "interactive service" could interact with Windows desktop and show a graphical user interface. In Windows Vista, however, interactive services are deprecated and may not operate properly, as a result of Windows Service hardening.
  • 1.4K
  • 21 Oct 2022
Topic Review
Helmy Eltoukhy
Helmy Eltoukhy is an American scientist and entrepreneur, best known for his contributions to genomics, semiconductor DNA sequencing, and personalized medicine. The co-founder of startups Avantome and Guardant Health, Eltoukhy was named to Time (magazine) ’s inaugural 50 Most Influential People in Healthcare (2018) and Fortune’s 40 under 40 (2017). Acquired by Illumina in 2008, Avantome was founded to develop and commercialize semiconductor-based DNA sequencing, during the race for the $1,000 genome. Guardant Health was founded to pioneer non-invasive liquid biopsy approaches for cancer diagnosis, monitoring, personalized medicine treatment, and research.
  • 1.4K
  • 28 Oct 2022
Topic Review
Left-Right Asymmetry
Left-right asymmetry (LR asymmetry) refers to differences in structure (symmetry breaking) across the mediolateral (left and right) plane in animals. This plane is defined with respect to the anteroposterior and dorsoventral axes and is perpendicular to both. Because the left-right plane is not strictly an axis (as it is not established through a morphogen gradient), to create asymmetry, the left and right sides need to be patterned separately. LR asymmetry is pervasive throughout metazoans and present throughout every major lineage. Notable examples include the large and small claws of the fiddler crab, the left offset of the vertebrate heart, asymmetrical gut coiling in Drosophila melanogaster, and dextral (clockwise) and sinistral (counterclockwise) coiling of gastropods. This asymmetry can be restricted to a specific organ or feature, as in the crab claws, or be expressed throughout the entire body as in snails.
  • 1.4K
  • 02 Nov 2022
Topic Review
Drug Carriers for Arthritis Therapy
Drug carriers are used to penetrate the biological barriers and deliver the requisite active pharmaceutical ingredients (API). This has greater significance for medication in arthritis therapies because the inflammatory progression of rheumatoid arthritis (RA) and osteoarthritis (OA) is complex, intertwined, and influenced by one another. For this purpose, the drug delivery systems (DDS) of this carrier are currently being investigated with exogenous triggers and endogenous stimuli. This flexible-release invention will solve the problems of multiple implantations and local toxic accumulation at the lesion sites.
  • 1.4K
  • 10 Nov 2022
Topic Review
STV Royston Grange
STV Royston Grange was a Houlder Line refrigerated cargo liner steamship that was built in England in 1959. In 1972 she collided with the tanker Tien Chee in the Río de la Plata. The resulting fire killed all 74 people aboard Royston Grange and eight people aboard Tien Chee. Royston Grange's burnt-out hulk was scrapped in Spain in 1979. Royston or Roystone Grange is an 18th-century farmstead next to the site of a medieval monastic grange at Ballidon in Derbyshire, England. Houlder Line had named ships after several English granges, including Royston, since the 1890s. This ship was the company's fifth and last Royston Grange.
  • 1.4K
  • 02 Dec 2022
Topic Review
Coastal Morphodynamics
The shape of the coast and the processes that mold it change together as a complex system. There is constant feedback among the multiple components of the system, and when climate changes, all facets of the system change. Abrupt shifts to different states can also take place when certain tipping points are crossed. The coupling of rapid warming in the Arctic with melting sea ice is one example of positive feedback. Climate changes, particularly rising sea temperatures, are causing an increasing frequency of tropical storms and “compound events” such as storm surges combined with torrential rains. These events are superimposed on progressive rises in relative sea level and are anticipated to push many coastal morphodynamic systems to tipping points beyond which return to preexisting conditions is unlikely. 
  • 1.4K
  • 02 Nov 2023
Topic Review
Hydroa Vacciniforme, EBV, and Lymphoma
Hydroa vacciniforme (HV) is a rare form of photosensitivity disorder in children or adolescence and is frequently associated with Epstein–Barr virus (EBV) infection, whereas HV-like lymphoproliferative disorders (HVLPD) describe a spectrum of EBV-associated T-cell or natural killer (NK)-cell lymphoproliferations with HV-like cutaneous manifestations, including EBV-positive HV, atypical HV, and HV-like lymphoma. 
  • 1.4K
  • 23 Dec 2020
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