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Topic Review
Quadjet
A quadjet or four-engine jet is a jet aircraft powered by four engines. The presence of four engines offers increased power output and redundancy, allowing quadjets to be used as civilian airliners, freighters and military aircraft. Many of the first purpose-built jetliners were quadjets, among which stands the De Havilland Comet, the world's first commercial jetliner. In the past two decades, the use of quadjet airliners has gradually begun to decline due to a variety of factors, including the approval of twinjets to fly further from diversion airports and an increased emphasis on fuel efficiency.
  • 2.3K
  • 24 Nov 2022
Topic Review
Path Planning Technique for Mobile Robots
Mobile robot path planning involves designing optimal routes from starting points to destinations within specific environmental conditions. Even though there are well-established autonomous navigation solutions, it is worth noting that comprehensive, systematically differentiated examinations of the critical technologies underpinning both single-robot and multi-robot path planning are notably scarce. These technologies encompass aspects such as environmental modeling, criteria for evaluating path quality, the techniques employed in path planning and so on.
  • 2.3K
  • 19 Jan 2024
Topic Review
Bioleaching
In bioleaching, the function of the solvent is performed by microorganisms, by the action of either bacteria or fungi, as they participate in the biogeochemical cycle of minerals in direct ways by the metabolism of the microorganisms or indirectly by the products of their metabolism. Therefore, bioleaching is defined as the solubilization of metals from insoluble solid substrates.
  • 2.3K
  • 18 Jul 2023
Topic Review
Desalination in China
In recent decades, the ever-growing demands for clean water in households and industries have urged researchers to take every possible step to deal with the global water crisis. Seawater desalination has turned out to be the most promising and efficient way to provide clean water. Owing to the advancement of synthetic chemistries and technologies, great success has been achieved in the desalination and utilization of seawater worldwide. China, with the world’s largest population, has pushed the development of desalination and multipurpose utilization of seawater further in respect of materials, technologies and services, etc. 
  • 2.3K
  • 30 Mar 2021
Topic Review
Melatonin in Wine and Beer
Melatonin is a hormone secreted in the pineal gland with several functions, especially regulation of circadian sleep cycle and the biological processes related to it. This review evaluates the bioavailability of melatonin and resulting metabolites, the presence of melatonin in wine and beer and factors that influence it, and finally the different benefits related to treatment with melatonin. When administered orally, melatonin is mainly absorbed in the rectum and the ileum; it has a half-life of about 0.45–1 h and is extensively inactivated in the liver by phase 2 enzymes. Melatonin (MEL) concentration varies from picograms to ng/mL in fermented beverages such as wine and beer, depending on the fermentation process. These low quantities, within a dietary intake, are enough to reach significant plasma concentrations of melatonin, and are thus able to exert beneficial effects. Melatonin has demonstrated antioxidant, anticarcinogenic, immunomodulatory and neuroprotective actions. These benefits are related to its free radical scavenging properties as well and the direct interaction with melatonin receptors, which are involved in complex intracellular signaling pathways, including inhibition of angiogenesis and cell proliferation, among others. In the present review, the current evidence on the effects of melatonin on different pathophysiological conditions is also discussed.
  • 2.3K
  • 08 Feb 2021
Topic Review
GAPDH-Mediated Autophagy
The cytosolic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has pleiotropic functions independent of its canonical role in glycolysis. The GAPDH functional diversity is mainly due to post-translational modifications in different amino acid residues or due to protein–protein interactions altering its localization from cytosol to nucleus, mitochondria or extracellular microenvironment. Non-glycolytic functions of GAPDH include the regulation of cell death, autophagy, DNA repair and RNA export, and they are observed in physiological and pathological conditions as cancer and neurodegenerative disorders
  • 2.3K
  • 09 Jun 2021
Topic Review
Polar Lipids from Olives/Olive Oil
Polar lipids are minor components of olives and olive oil and include a myriad of molecules such as phospholipids and glycolipids.
  • 2.3K
  • 01 Jul 2021
Topic Review
Romantic Love and Sleep
“Romantic love is a motivational state typically associated with a desire for long-term mating with a particular individual. It occurs across the lifespan and is associated with distinctive cognitive, emotional, behavioural, social, genetic, neural, and endocrine activity in both sexes. Throughout much of the life course, it serves mate choice, courtship, sex, and pair-bonding functions. It is a suite of adaptations and by-products that arose sometime during the recent evolutionary history of humans”. Sleep is common in the animal kingdom, although it takes various forms. Sleep in humans is defined “on the basis of both behaviour of the person while asleep and the related physiologic changes that occur to the waking brain’s electrical rhythm in sleep”. Behavioural characteristics of sleep include lack of mobility or slight mobility, closed eyes, a characteristic species-specific sleeping posture, reduced response to external stimulation, quiescence, increased reaction time, elevated arousal threshold, impaired cognitive function, and a reversible unconscious state. It includes non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. Non-rapid eye movement sleep is characterised by synchronised electroencephalographic activity, mildly reduced muscle tone, and slow rolling eye movements. Rapid eye movement sleep is characterised by theta or saw tooth waves and desynchronised electroencephalographic activity, moderately to severely reduced or absent muscle tone, and rapid eye movements. There are three stages of NREM sleep (i.e., N1, N2, N3) and one stage of REM sleep.
  • 2.3K
  • 27 Jan 2022
Topic Review
The Feature, Performance of Advanced Electrodes for Electroencephalogram
An electroencephalogram (EEG) is a graph of the difference in voltage between brain scalp locations over time. Since EEG signals are non-stationary and random, they usually present low signal intensity and high noise. Therefore, the development of advanced electrodes to obtain high-quality EEG signals is a very attractive but challenging research topic. Ag/AgCl wet electrodes have been widely used to record brain potentials in real life. However, the use of conductive gels still faces many challenges. Advanced electrodes such as semi-dry, dry contact, dry non-contact, and microneedle array electrodes have been developed to overcome the issues. In this entry, the physical features and EEG signal acquisition performances of these advanced EEG electrodes are introduced in view of the differences in contact between the skin and electrodes. Specifically, contact features, biofeatures, impedance, signal quality, and artifacts are discussed.
  • 2.3K
  • 29 Jan 2023
Topic Review
T Cells and Adaptive Immune System in SARS-CoV-2
The coronavirus 2019 (COVID-19) pandemic was caused by a positive sense single-stranded RNA (ssRNA) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Prior COVID-19 research on immunogens understandably focused on nAb responses, with less interest in overall cellular immunity. Interestingly, there is data accumulating which suggests that T cell responses are an important player in both natural and adaptive immunity as well as vaccine protection against chronic COVID-19 disease.
  • 2.3K
  • 20 Feb 2023
Topic Review
Liquid Crystal Elastomer
Liquid crystal elastomer (LCE) describes a class of materials that combine the elastic entropy behaviour associated with conventional elastomers with the stimuli responsive properties of anisotropic liquid crystals. LCEs consequently exhibit attributes of both elastomers and liquid crystals, but additionally have unique properties not found in either. Recent developments in LCE synthesis, as well as the understanding of the behaviour of liquid crystal elastomers—namely their mechanical, optical and responsive properties—is of significant relevance to biology and biomedicine. LCEs are abundant in nature, highlighting the potential use of LCEs in biomimetics. Their exceptional tensile properties and biocompatibility have led to research exploring their applications in artificial tissue, biological sensors and cell scaffolds by exploiting their actuation and shock absorption properties. There has also been significant recent interest in using LCEs as a model for morphogenesis.
  • 2.3K
  • 19 Apr 2021
Topic Review
Plant Species and Expression Systems on Vaccines Production
Use of plant cells as vaccine production hosts is appropriate for the expression of complex antigens in a cost-efficient manner. Recombinant proteins can be produced using various expression systems, each of which has its own benefits and disadvantages pertaining to the yield, time required for expression and the costs incurred in this process.
  • 2.3K
  • 18 Jan 2023
Topic Review
[18F]Difluoromethyl Heteroaryl-Sulfones
The suitability of the 18F radioisotope in positron emission tomography (PET) demanded novel approaches for 18F-fluorination and 18F-fluoroalkylation. The difluoromethyl (CF2H) group has gained increasing attention in medicinal chemistry due to its lipophilic hydrogen-bond donor properties. In non-radioactive chemistry, difluoromethyl heteroaryl-sulfones has been extensively used in difluoromethylation of substrates bearing C=C, C≡C, and C≡N bonds by visible light photoredox catalysis. Herein, we highlight our recent work on the synthesis of [18F]difluoromethyl heteroaryl-sulfones with improved molar activities and their application in photoinduced C-H 18F-difluoromethylation of N-containing heteroarenes via a radical-mediated pathway.
  • 2.3K
  • 25 Aug 2021
Topic Review
Lateral Organization of PI(4,5)P2
Phosphatidylinositol 4,5- bisphosphate (PI(4,5)P2) is a minor but ubiquitous component of the inner leaflet of the plasma membrane of eukaryotic cells. However, due to its particular complex biophysical properties, it stands out from its neighboring lipids as one of the most important regulators of membrane-associated signaling events. Despite its very low steady-state concentration, PI(4,5)P2 is able to engage in a multitude of simultaneous cellular functions that are temporally and spatially regulated through the presence of localized transient pools of PI(4,5)P2 in the membrane.
  • 2.3K
  • 04 Nov 2020
Topic Review
Genus Ochrobactrum
Ochrobactrum spp. are found in a wide range of environments including soils and water. They are non-enteric, Gram-negative organisms that are closely related to the genus Brucella. Several species of this genus have now been characterised and implicated as opportunistic pathogens in multiple outbreaks. This entry gives a brief overview of the Genus Ochrobactrum.
  • 2.3K
  • 27 Nov 2020
Topic Review
Medical Applications of Chitin
Chitin is a universal biopolymer that is found in microbes, plants, fungi, the exoskeleton of insects, various species of algae, and bottom-feeding crustaceans. This (1–4)-linked N-acetyl-ß-D-glucosamine polysaccharide can be readily processed with simple chemical procedures without putting a species at risk. Chitin has garnered interest as an alternative substance that can be used in the medical, environmental, and agricultural sectors.
  • 2.3K
  • 29 Mar 2022
Topic Review
Education 4.0 in Developing Economies
Education 4.0 (EDUC4) was driven by the onset of the Fourth Industrial Revolution (4IR) to meet labor market requirements resulting from learning that is customized, flexible, accessible, and skills-based.
  • 2.3K
  • 01 Dec 2021
Topic Review
Sustainability of HVAC Systems in Buildings
Increasing demand on heating, ventilation, and air-conditioning (HVAC) systems and their importance, as the respiratory system of buildings, in developing and spreading various microbial contaminations and diseases with their huge global energy consumption share have forced researchers, industries, and policymakers to focus on improving the sustainability of HVAC systems. 
  • 2.3K
  • 03 Mar 2022
Topic Review
Australian Tropical Medicinal Plants
Australian tropical plants have been a rich source of food (bush food) and medicine to the first Australians (Aboriginal people), who are believed to have lived for more than 50,000 years. Plants such as spreading sneezeweed (Centipeda minima), goat’s foot (Ipomoea pes-caprae), and hop bush (Dodonaea viscosa and D. polyandra) are a few popular Aboriginal medicinal plants.
  • 2.3K
  • 01 Jul 2022
Topic Review
Mitochondrial VDAC1 as Therapeutic Target of Inflammation-Related Diseases
The multifunctional protein, voltage-dependent anion channel 1 (VDAC1), is located on the mitochondrial outer membrane. It is a pivotal protein that maintains mitochondrial function to power cellular bioactivities via energy generation. VDAC1 is involved in regulating energy production, mitochondrial oxidase stress, Ca2+ transportation, substance metabolism, apoptosis, mitochondrial autophagy (mitophagy), and many other functions. VDAC1 malfunction is associated with mitochondrial disorders that affect inflammatory responses, resulting in an up-regulation of the body’s defensive response to stress stimulation. Overresponses to inflammation may cause chronic diseases. Mitochondrial DNA (mtDNA) acts as a danger signal that can further trigger native immune system activities after its secretion. VDAC1 mediates the release of mtDNA into the cytoplasm to enhance cytokine levels by activating immune responses. VDAC1 regulates mitochondrial Ca2+ transportation, lipid metabolism and mitophagy, which are involved in inflammation-related disease pathogenesis. 
  • 2.3K
  • 26 Oct 2022
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