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Topic Review
The Andromeda Galaxy
Star formation histories of galaxies are critically important for understanding the process of galaxy formation and the structure and contents of galaxies. Star formation can and has been studied in local galaxies for which the stellar populations are resolved and in more distant galaxies for which stars are unresolved, which are instead modeled as populations. Structural components of a galaxy can be resolved at much larger distances. The structural components include those long recognized, such as bulge, disk and halo. More recently recognized structures include separation of disks into thin and thick disk components and stellar streams, as well as recognition of significant numbers of dwarf companion galaxies. Stellar streams are the most recently recognized components of galaxies, mainly using observations of the Milky Way and the Andromeda Galaxy (M31).
  • 2.4K
  • 14 Aug 2023
Topic Review
Applications of electrolyzed water
As the situation of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is still de-teriorating, there has been a huge increase in the demand and use of disinfectants. Electrolyzed water (EW), as a novel broad-spectrum disinfectant and cleaner, has been widely used for several years.
  • 2.4K
  • 26 Jan 2021
Topic Review
Cepheus
Cepheus is a northern constellation named after the mythical king of Aethiopia in Greek mythology. Positioned in the celestial northern hemisphere, it is recognizable for its distinctive shape resembling a house with a peaked roof. Cepheus is home to several notable deep-sky objects, including the famous variable star Delta Cephei, which gave its name to a class of pulsating stars known as Cepheid variables.
  • 2.4K
  • 29 Feb 2024
Topic Review
PANoptosis
Consideration of the totality of biological effects from cell death in multiple studies has led to the conceptualization of PANoptosis, a unique inflammatory cell death pathway that integrates components from other cell death pathways. PANoptosis is implicated in driving innate immune responses and inflammation and cannot be individually accounted for by pyroptosis, apoptosis, or necroptosis alone. PANoptosis is regulated by multifaceted macromolecular complexes called PANoptosomes.
  • 2.4K
  • 02 Jun 2022
Topic Review
Nanopore Sequencing
Nanopore sequencing is a third generation approach used in the sequencing of biopolymers — specifically, polynucleotides in the form of DNA or RNA. Using nanopore sequencing, a single molecule of DNA or RNA can be sequenced without the need for PCR amplification or chemical labeling of the sample. Nanopore sequencing has the potential to offer relatively low-cost genotyping, high mobility for testing, and rapid processing of samples with the ability to display results in real-time. Publications on the method outline its use in rapid identification of viral pathogens, monitoring ebola, environmental monitoring, food safety monitoring, human genome sequencing, plant genome sequencing, monitoring of antibiotic resistance, haplotyping and other applications.
  • 2.4K
  • 16 Nov 2022
Topic Review
Semantic Memory
Semantic memory refers to general world knowledge that we have accumulated throughout our lives. This general knowledge (facts, ideas, meaning and concepts) is intertwined in experience and dependent on culture. Semantic memory is distinct from episodic memory, which is our memory of experiences and specific events that occur during our lives, from which we can recreate at any given point. For instance, semantic memory might contain information about what a cat is, whereas episodic memory might contain a specific memory of petting a particular cat. We can learn about new concepts by applying our knowledge learned from things in the past. Semantic memory and episodic memory are both types of explicit memory (or declarative memory), that is, memory of facts or events that can be consciously recalled and "declared". The counterpart to declarative or explicit memory is nondeclarative memory or implicit memory.
  • 2.4K
  • 22 Nov 2022
Topic Review
Detecting Analytes in Urine for Urinalysis
Human urine samples contain several components that can indicate the health condition of a patient, and therefore aid in the diagnosis of common clinical conditions such as diabetes mellitus (DM), urinary tract infections (UTIs), renal stone disease, kidney disorders, liver problems, obesity, other metabolic disorders, or fetal hypothyroidism. Urine samples also provide evidence of underlying health problems in pre-symptomatic and asymptomatic individuals, which can facilitate early intervention and therapy. These benefits play an important role in encouraging individual access to continuous and regular health monitoring.
  • 2.4K
  • 06 Dec 2022
Topic Review
Essential Oils
Naturally produced by aromatic plants, essential oils (EO) contain a wide range of volatile molecules, including mostly secondary metabolites, which possess several biological activities. Essential oils properties such as antioxidant, antimicrobial and anti-inflammatory activities are known for a long time and hence widely used in traditional medicines, cosmetics and food industries. However, despite their effects against many phytopathogenic fungi, oomycetes and bacteria as well as weeds, their use in agriculture remains surprisingly scarce. The purpose of the present review is to gather and discuss up-to-date biological activities of EO against weeds, plant pathogenic fungi, oomycetes and bacteria, reported in the scientific literature. Innovative methods, potentially valuable to improve the efficiency and reliability of EO, have been investigated. In particular, their use towards a more sustainable agriculture has been discussed, aiming at encouraging the use of alternative products to substitute synthetic pesticides to control weeds and plant diseases, without significantly affecting crop yields.
  • 2.4K
  • 17 Jan 2022
Topic Review
Amalgam
An amalgam is an alloy of mercury with another metal. It may be a liquid, a soft paste or a solid, depending upon the proportion of mercury. These alloys are formed through metallic bonding, with the electrostatic attractive force of the conduction electrons working to bind all the positively charged metal ions together into a crystal lattice structure. Almost all metals can form amalgams with mercury, the notable exceptions being iron, platinum, tungsten, and tantalum. Silver-mercury amalgams are important in dentistry, and gold-mercury amalgam is used in the extraction of gold from ore. Dentistry has used alloys of mercury with metals such as silver, copper, indium, tin and zinc.
  • 2.4K
  • 31 Oct 2022
Topic Review
Ginseng against Respiratory Tract Infections
Ginseng has been reported to inhibit bacterial pathways, thereby killing bacteria indirectly. It has also been shown to protect the host from bacterial invasion.
  • 2.4K
  • 30 Sep 2021
Topic Review
Bioactive Mycocompounds of Selected Medicinal Mushrooms for HPV
Medicinal mushrooms have been used as a medicinal tool for many centuries and, nowadays, are used in the prevention and therapy of various diseases, including as an adjunct to cancer treatment. It is estimated that 14–16% of global cancer cases are caused by infectious events; one well-known infectious agent that leads to cancer is the human papillomavirus (HPV). HPV is responsible for more than 99.7% of cervical cancer cases and also may play a role in vaginal, vulvar, penile, anal, rectal, and oropharyngeal carcinogenesis. Coriolus versicolor, a basidiomycetes class mushroom, consists of glycoproteins called polysaccharide-K (PSK) and polysaccharopeptide (PSP), which are mainly responsible for its effectiveness in the fight against a variety of cancers. Its beneficial effect lies in its ability to arrest different phases of the cell cycle, immunomodulation or induction of apoptosis. Coriolus versicolor extractcan reduces BCL-2 expression or increases the expression of p53 tumour suppressor genes in breast tumour cell lines. Inhibition of proliferation was also demonstrated with HeLa cells, while cervical cytology abnormalities improved in patients who locally applied Coriolus versicolor-based vaginal gel. Coriolus versicolor extract itself, and also its combination with another medicinal mushroom, Ganoderma lucidum, leads to improved HPV clearance in HPV cervical or oral-positive patients. Medicinal mushrooms can also increase the effectiveness of vaccination.
  • 2.4K
  • 11 Apr 2023
Topic Review
Satellite Navigation Signal Authentication Principles and Technical Architecture
As the Global Navigation Satellite System (GNSS) is widely used in all walks of life, the signal structure of satellite navigation is open, and the vulnerability to spoofing attacks is also becoming increasingly prominent, which will seriously affect the credibility of navigation, positioning, and timing (PNT) services. Satellite navigation signal authentication technology is an emerging technical means of improving civil signal anti-spoofing on the satellite navigation system side, and it is also an important development direction and research focus of the GNSS. 
  • 2.4K
  • 12 Apr 2023
Topic Review
Nanofluids
Nanofluids are advanced category of fluids that are formed by dispersing nano scaled particles within non-dissolving conventional fluids. What makes such suspensions favourable to many thermal applications is that the developed thermal property of the fabricated fluid becomes somewhere within the range of that of the added solid particles and that of the conventional basefluid used. Nevertheless, the main challenges that faces the commercialization of such class of fluids are: 1- maintaining the physical stability of the dispersion, which otherwise can leads to a degradation in the effective thermophysical properties with time; and 2- the accompanied increase in effective viscosity of the mixture that generally cause the pressure losses in the system to increase, and hence the pumping power demands rises accordingly.    
  • 2.4K
  • 26 Aug 2020
Topic Review
Biofuel Vehicles
Biofuels and bioenergy are produced by processing biomass, or organic matter, from plants, crops, and their waste products. Biofuel can displace fuels made from petroleum because it comes from renewable sources. The only alternative energy source that can provide liquid fuels to take the place of fossil fuels is bioenergy. Biofuels are a viable alternative to meet future demand while reducing greenhouse gas emissions and environmental effects.
  • 2.4K
  • 18 Mar 2024
Topic Review
Red Blood Cells Metabolism beyond Glycolysis
Red blood cells (RBC) are the most abundant cell in the human body, with a central role in oxygen transport and its delivery to tissues. The relative simplicity of RBCs, as historically perceived, has attracted multiple efforts to leverage them as a model of simplified human cell metabolism. Indeed, RBCs exclusively rely on glycolysis (Embden–Meyerhof–Parnas pathway) to generate high-energy phosphate compounds, such as adenosine triphosphate (ATP)—whose main source in other cells is oxidative phosphorylation in mitochondria.
  • 2.4K
  • 13 Jul 2023
Topic Review
Reaction
As described by the third of Newton's laws of motion of classical mechanics, all forces occur in pairs such that if one object exerts a force on another object, then the second object exerts an equal and opposite reaction force on the first. The third law is also more generally stated as: "To every action there is always opposed an equal reaction: or the mutual actions of two bodies upon each other are always equal, and directed to contrary parts." The attribution of which of the two forces is the action and which is the reaction is arbitrary. Either of the two can be considered the action, while the other is its associated reaction.
  • 2.4K
  • 30 Oct 2022
Topic Review
Zinc Deficiency
Zinc deficiency is defined either as insufficient zinc to meet the needs of the body, or as a serum zinc level below the normal range. However, since a decrease in the serum concentration is only detectable after long-term or severe depletion, serum zinc is not a reliable biomarker for zinc status. Common symptoms include increased rates of diarrhea. Zinc deficiency affects the skin and gastrointestinal tract; brain and central nervous system, immune, skeletal, and reproductive systems. Zinc deficiency in humans is caused by reduced dietary intake, inadequate absorption, increased loss, or increased body system use. The most common cause is reduced dietary intake. In the U.S., the Recommended Dietary Allowance (RDA) is 8 mg/day for women and 11 mg/day for men. The highest concentration of dietary zinc is found in oysters, meat, beans, and nuts. Increasing the amount of zinc in the soil and thus in crops and animals is an effective preventive measure. Zinc deficiency may affect up to 2 billion people worldwide.
  • 2.4K
  • 27 Oct 2022
Topic Review
Supercritical Carbon Dioxide(s-CO2) Power Cycle
Supercritical CO2 power cycles have been deeply investigated in recent years. However, their potential in waste heat recovery is still largely unexplored. This paper presents a critical review of engineering background, technical challenges, and current advances of the s-CO2 cycle for waste heat recovery. Firstly, common barriers for the further promotion of waste heat recovery technology are discussed. Afterwards, the technical advantages of the s-CO2 cycle in solving the abovementioned problems are outlined by comparing several state-of-the-art thermodynamic cycles. On this basis, current research results in this field are reviewed for three main applications, namely the fuel cell, internal combustion engine, and gas turbine. For low temperature applications, the transcritical CO2 cycles can compete with other existing technologies, while supercritical CO2 cycles are more attractive for medium- and high temperature sources to replace steam Rankine cycles. Moreover, simple and regenerative configurations are more suitable for transcritical cycles, whereas various complex configurations have advantages for medium- and high temperature heat sources to form cogeneration system. Finally, from the viewpoints of in-depth research and engineering applications, several future development directions are put forward. This review hopes to promote the development of s-CO2 cycles for waste heat recovery.
  • 2.4K
  • 25 Nov 2020
Topic Review
Lemongrass Essential Oil
Cymbopogon spp. are fast-growing C4 perennial sedges from the grass family Poaceae and are primarily cultivated for their essential oils. The genus lemongrass comprises about 180 species, such as Cymbopogon citratus, Cymbopogon flexuosus, Cymbopogon winterianus, Cymbopogon martinii, Cymbopogon nardus, and Cymbopogon refractus. Lemongrass (Cymbopogonspp.) oil is a cocktail of various terpenes and terpenoids, out of which the major components belong to cyclic and acyclic monoterpenes. The monoterpenes are derived from geranyl diphosphate (GPP).
  • 2.4K
  • 29 Mar 2022
Topic Review
Safety-Management Practices and Occupational Accidents
Occupational accidents in organizations result in huge damages to employees’ lives every year. However, organizations have financial costs to bear in terms of productivity, compensation paid, and workdays lost. In addition, they also face the nonfinancial cost of occupational accidents, e.g., the psychological trauma of employee absence from work. In the last two decades, investigations of major industrial accidents pointed out leading factors, e.g., poor safety management. Therefore, attention to occupational accident prevention has been shifted from human and technical errors to catering employees’ safety with management practices. In this regard, safety management plays the most significant role in intervening in the caution process of occupational accidents. 
  • 2.4K
  • 28 Apr 2022
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