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Topic Review
Quinolones
Fluoroquinolones (FQs) are arguably among the most successful antibiotics of recent times. They have enjoyed over 30 years of clinical usage and become essential tools in the armoury of clinical treatments. FQs target the bacterial enzymes DNA gyrase and DNA topoisomerase IV, where they stabilise a covalent enzyme-DNA complex in which the DNA is cleaved in both strands. This leads to cell death and turns out to be a very effective way of killing bacteria. However, resistance to FQs is increasingly problematic, and alternative compounds are urgently needed.
  • 3.6K
  • 25 Dec 2020
Topic Review
Fungal decomposition of dead wood
Fungi create a nutritional niche for deadwood-eaters ------------------------------ Direct comparison of the amounts of essential nutrients and ergosterol in wood provides evidence that the changes in the stoichiometry of decaying dead wood are driven by the action of fungi. They infest dead wood to take advantage of the ample supply of an energy-rich substrate. However, to exploit this resource, these fungi must import an array of essential nutrients from outside of the dead wood. This nutritional enrichment of dead wood creates a nutritional niche for xylophages that allows them to grow, develop, and reach maturity. Therefore, xylophagous beetles (considered as “wood-eaters”) are unable to gather the necessary amounts of nutrients from pure dead wood to grow and mature, but instead must utilize fungal tissues. ------------------------------
  • 3.6K
  • 03 Nov 2020
Topic Review
PIP2 Regulation in Cell
Phosphoinositides play a crucial role in regulating many cellular functions, such as actin dynamics, signaling, intracellular trafficking, membrane dynamics, and cell–matrix adhesion. Central to this process is phosphatidylinositol bisphosphate (PIP2). The levels of PIP2 in the membrane are rapidly altered by the activity of phosphoinositide-directed kinases and phosphatases, and it binds to dozens of different intracellular proteins. Despite the vast literature dedicated to understanding the regulation of PIP2 in cells over past 30 years, much remains to be learned about its cellular functions. Here, we focus on past and recent exciting results on different molecular mechanisms that regulate cellular functions by binding of specific proteins to PIP2 or by stabilizing phosphoinositide pools in different cellular compartments. Moreover, this review summarizes recent findings that implicate dysregulation of PIP2 in many diseases.
  • 3.6K
  • 19 Nov 2020
Topic Review
Indoor Air Quality in Healthcare Units
Indoor air quality (IAQ) in Healthcare Units is a complex and dynamic issue of utmost importance for patient safety and occupational health purposes, since healthcare providers, medical practitioners, staff and patients spend long hours in the facilities subject to their inherent air quality. IAQ is affected by outdoor air quality, indoor activities, indoor occupant density, ventilation practices, indoor intrinsic emissions (e.g., equipment/furniture/coatings). The presence of vulnerable individuals and the characteristics of the ongoing activities highlight the importance of adequately managing IAQ in healthcare facilities. Headaches, fatigue, dryness and irritation of the eyes and skin are common complaints of healthcare professionals, which have often been associated with poor IAQ. In addition, hospitals operate on a full-time basis (24 h per day, seven days a week), with no idle time to recover from activities’ emissions and consequent impact on IAQ.
  • 3.6K
  • 20 Jan 2022
Topic Review Peer Reviewed
COVID-19 and Bell’s Palsy
There are various neurological manifestations of coronavirus disease 2019 (COVID-19). Recent data suggest a connection between hemifacial paralysis, or Bell’s palsy, and COVID-19. Although the etiology of Bell’s palsy is unknown, the leading proposed etiology is viral in nature. Since the onset of the pandemic, numerous studies have investigated the relationship between Bell’s palsy, COVID-19 infection, and COVID-19 vaccination. The researchers studied the current literature on the topic of COVID-19 as it relates to Bell’s palsy. 
  • 3.6K
  • 13 Dec 2022
Topic Review
Types of Supercapacitors
Supercapacitors are mainly divided into three types: electrical double layer (EDL) capacitors, pseudocapacitors, and hybrid supercapacitors based on their energy storage mechanisms. 
  • 3.6K
  • 27 Apr 2023
Topic Review
Water radical cations
The study of water continues to provide surprises as evidenced by recent work on the surfaces of small droplets. Systems comprising numbers of water molecules and corresponding cations represent a topic of special interest, such as nuclear safety, functional biomolecules (DNA, RNA, and proteins) damage, proton transfer process and so on. To date, water radical cations have been created through wet nitrogen ionized as a result of subjected to electron-impact ionization, photoionization of a water molecular beam or vapor, even including in helium nanodroplets. They have also been generated through intermolecular coulomb decay process by high-energy photos or above 70 eV electrons impactions.For (H2O)2+•, a theoretical simulation led to both the structure resulting from proton transfer and the dimer cation structure. For larger water radical cations, these clusters are easily constructed from the (H2O)nH+ structures by substituting one of the water molecules, which is the next neighbor of the charged site for •OH radical. Besides the ultra-fast proton transfer reaction within (H2O)n+• , and between (H2O)n+• and its neighboring water molecules to form the proton transfer product, (H2O)n+• also present ultrafast charge migration from a solute M to (H2O)n+•.
  • 3.6K
  • 27 Oct 2020
Topic Review
Drone Brood
Drone brood homogenate (known as apilarnil or less apistimul) is a bee product obtained by the collection of drone (male honeybees)  larvae from drone cells of honey comb, from 3 to 11 days after hatching. Apilarnil, which may be defined as the male equivalent of royal jelly, is obtained from drone brood and then freeze-dried. Etymologically, the term originates from “api” for bee, “lar” for larvae, and “nil” as a shortened form of its discoverer’s name - Romanian apitherapist Nicholae Iliesiu. 
  • 3.6K
  • 17 Dec 2020
Topic Review
Differential Signaling
Differential signaling is a method for electrically transmitting information using two complementary signals. The technique sends the same electrical signal as a differential pair of signals, each in its own conductor. The pair of conductors can be wires in a twisted-pair or ribbon cable or traces on a printed circuit board. Electrically, the two conductors carry voltage signals which are equal in magnitude, but of opposite polarity. The receiving circuit responds to the difference between the two signals, which results in a signal a magnitude twice as large. Any interference caused by the transmission of differential signals tend to cancel out resulting in reduced emission that could affect nearby circuits.
  • 3.6K
  • 02 Nov 2022
Topic Review
Beer Polyphenols
Polyphenolic molecules can be found in different stages during the brewing process and react with proteins: during wort boiling, they form the hot break; during cooling, they form the cold break; and during post-fermentation, they are involved in the formation of chill haze and permanent hazes and facilitate the removal of undesirable compounds with filtration. However, they tend to react with proteins in packaged beer and form undesirable haze after the expiration date. As mentioned before, polyphenols can enter beer from hop and malt.
  • 3.6K
  • 15 Jun 2021
Topic Review
Carbon Coating Method
The carbon coating has the following main mechanisms: (1) Modifying surface chemical stability, (2) Enhancing structural stability, and (3) Improving Li-ion diffusion. 
  • 3.6K
  • 07 Jul 2022
Topic Review
Raw Materials for Geopolymer Production
Due to the high generation of industrial waste by-products, disposal concerns, less utilization, and hazardous nature, the research on its valorization as a precursor for geopolymer production is potentially environmentally viable.
  • 3.6K
  • 18 Oct 2022
Topic Review
Normative Social Influence
Normative social influence is a type of social influence that leads to conformity. It is defined in social psychology as "...the influence of other people that leads us to conform in order to be liked and accepted by them." The power of normative social influence stems from the human identity as a social being, with a need for companionship and association. Normative social influence involves a change in behaviour that is deemed necessary in order to fit in a particular group. The need for a positive relationship with the people around leads us to conformity. This fact often leads to people exhibiting public compliance—but not necessarily private acceptance—of the group's social norms in order to be accepted by the group. Social norms refers to the unwritten rules that govern social behavior. These are customary standards for behavior that are widely shared by members of a culture. In many cases, normative social influence serves to promote social cohesion. When a majority of group members conform to social norms, the group generally becomes more stable. This stability translates into social cohesion, which allows group members to work together toward a common understanding, or "good," but also has the unintended impact of making the group members less individualistic.
  • 3.6K
  • 08 Nov 2022
Topic Review
Arthropoda
Arthropods (/ˈɑːrθrəpɒd/, from grc ἄρθρον (arthron) 'joint', and πούς (pous) 'foot' (gen. ποδός)) are invertebrate animals having an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and cuticle made of chitin, often mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an external skeleton. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior organs; it has an open circulatory system. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. Their nervous system is "ladder-like", with paired ventral nerve cords running through all segments and forming paired ganglia in each segment. Their heads are formed by fusion of varying numbers of segments, and their brains are formed by fusion of the ganglia of these segments and encircle the esophagus. The respiratory and excretory systems of arthropods vary, depending as much on their environment as on the subphylum to which they belong. Arthropods use combinations of compound eyes and pigment-pit ocelli for vision. In most species, the ocelli can only detect the direction from which light is coming, and the compound eyes are the main source of information, but the main eyes of spiders are ocelli that can form images and, in a few cases, can swivel to track prey. Arthropods also have a wide range of chemical and mechanical sensors, mostly based on modifications of the many bristles known as setae that project through their cuticles. Similarly, their reproduction and development are varied; all terrestrial species use internal fertilization, but this is sometimes by indirect transfer of the sperm via an appendage or the ground, rather than by direct injection. Aquatic species use either internal or external fertilization. Almost all arthropods lay eggs, but many species give birth to live young after the eggs have hatched inside the mother, and a few are genuinely viviparous, such as aphids. Arthropod hatchlings vary from miniature adults to grubs and caterpillars that lack jointed limbs and eventually undergo a total metamorphosis to produce the adult form. The level of maternal care for hatchlings varies from nonexistent to the prolonged care provided by social insects. The evolutionary ancestry of arthropods dates back to the Cambrian period. The group is generally regarded as monophyletic, and many analyses support the placement of arthropods with cycloneuralians (or their constituent clades) in a superphylum Ecdysozoa. Overall, however, the basal relationships of animals are not yet well resolved. Likewise, the relationships between various arthropod groups are still actively debated. Today, Arthropods contribute to the human food supply both directly as food, and more importantly, indirectly as pollinators of crops. Some species are known to spread severe disease to humans, livestock, and crops.
  • 3.6K
  • 10 Nov 2022
Topic Review
Water-Saving Agricultural Technologies
Increasing food demand has exerted tremendous stress on agricultural water usages worldwide, often with a threat to sustainability in agricultural production and, hence, food security. Various resource-conservation technologies like conservation agriculture (CA) and water-saving measures are being increasingly adopted to overcome these problems. While these technologies provide some short- and long-term benefits of reduced labor costs, stabilized or increased crop yield, increased water productivity, and improved soil health at farm scale, their overall impacts on hydrology outcomes remain unclear at larger temporal and spatial scales. Although directly linked to the regional hydrological cycle, irrigation remains a less understood component. The ecological conditions arising from the hydrology outcomes of resource-conservation technologies are associated with sustainability in agricultural production.
  • 3.6K
  • 22 Mar 2021
Topic Review Peer Reviewed
Trust in Science and COVID-19
In this entry, trust in science is defined as the reliance, confidence, and dependence on science to understand scientific information. With the outbreak of, and the uncertainty surrounding the COVID-19 pandemic, turning towards science and trusting the specialized knowledge of experts is of particular importance during this period.
  • 3.6K
  • 13 Apr 2022
Topic Review
Nail Mini-Organ Stem Cells
Nails are highly keratinized skin appendages that exhibit continuous growth under physiological conditions and full regeneration upon removal. These mini-organs are maintained by two autonomous populations of skin stem cells. The fast-cycling, highly proliferative stem cells of the nail matrix (nail stem cells (NSCs)) predominantly replenish the nail plate. Furthermore, the slow-cycling population of the nail proximal fold (nail proximal fold stem cells (NPFSCs)) displays bifunctional properties by contributing to the peri-nail epidermis under the normal homeostasis and the nail structure upon injury. Here, we discuss nail mini-organ stem cells’ location and their role in skin and nail homeostasis and regeneration, emphasizing their importance to orchestrate the whole digit tip regeneration. Such endogenous regeneration capabilities are observed in rodents and primates. However, they are limited to the region adjacent to the nail’s proximal area, indicating the crucial role of nail mini-organ stem cells in digit restoration.
  • 3.6K
  • 04 May 2021
Topic Review
TiO2
TiO2 probably plays the most important role in photocatalysis due to its excellent chemical and physical properties. However, the band gap of TiO2 corresponds to the Ultraviolet (UV) region, which is inactive under visible irradiation. At present, TiO2 has become activated in the visible light region by metal and nonmetal doping and the fabrication of composites. Recently, nano-TiO2 has attracted much attention due to its characteristics of larger specific surface area and more exposed surface active sites. nano-TiO2 has been obtained in many morphologies such as ultrathin nanosheets, nanotubes, and hollow nanospheres.
  • 3.6K
  • 29 Oct 2020
Topic Review
Online Food Delivery Platforms
In the midst of the global 2020 COVID-19 outbreak, the advantages of online food delivery (FD) were obvious as it facilitated consumer access to prepared meals and enabled food providers to keep operating. However, online FD is not without its critics, with reports of consumer and restaurant boycotts. It is therefore time to take stock and consider the broader impacts of online FD and what they mean for the stakeholders involved. Using the three pillars of sustainability as a lens through which to consider the impacts, this review presents the most up-to-date research in this field revealing a raft of positive and negative impacts. From an economic standpoint, online FD while providing job and sale opportunities has been criticized for high commissions it charges restaurants and questionable working conditions for delivery people. From a social perspective, online FD is affecting the relationship between consumers and their food as well as influencing public health outcomes and traffic systems. Environmental impacts include the generation of worrying amounts of waste and its high carbon footprints. Stakeholders must consider how best to mitigate the negative and promote the positive impacts of online FD to ensure that it is sustainable, in every sense, moving forward.
  • 3.6K
  • 04 Aug 2020
Topic Review
Crystallization of LiNbO3
Due to its piezoelectric, ferroelectric, nonlinear optics, and pyroelectric properties, LiNbO3 crystal has found its wide applications in surface acoustic wave (SAW) devices, optical waveguides, optical modulators, and second-harmonic generators (SHG). LiNbO3 crystallized as R3c space group below Curie temperature shows spontaneous polarization that leads to its ferroelectric and piezoelectric properties. Physical and chemical characteristics of LiNbO3 are mainly determined by Li/Nb ratio, impurity cations, vacancies in a cation sublattice. Different sizes of LiNbO3 ranging from nanoscale and microscale to bulk size have been synthesized by solid state method, hydrothermal/solvothermal method, Czochralski (Cz) growth method, etc. Most basic and applied studies of LiNbO3 focus on its bulk single crystal.
  • 3.6K
  • 17 Dec 2021
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