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Topic Review
Copper-Based Diamond-like Thermoelectric Compounds
Copper-based diamond-like compounds (CBDL) compounds contain a large number of family members, which include ternary I–III–VI2 chalcopyrites, I3–V–VI4 stannites, I2–IV–VI3 stannites, quaternary I2–II–IV–VI4 compounds, and even large-cell Cu10B2C4D13 tetrahedrites and Cu26P2Q6S32 colusites.
  • 850
  • 11 May 2023
Topic Review
Ore-Forming Fluid
The He-Ar isotopic compositions showed that the 3He/4He ratios of the ore-forming fluid of the Xingluokeng deposit ranged from 0.14 to 1.01 Ra (Ra is the 3He/4He ratio of air, 1 Ra = 1.39 × 10−6), with an average of 0.58 Ra, which is between the 3He/4He ratios of mantle fluids and crustal fluids, suggesting that the mantle-derived He was added to the mineralizing fluid, with a mean of 8.7%. The 40Ar/36Ar ratios of these samples ranged from 361 to 817, with an average of 578, between the atmospheric 40Ar/36Ar and the crustal and/or mantle 40Ar/36Ar.
  • 848
  • 24 May 2022
Topic Review
Microbial Natural Products with Wound-Healing Properties
Wound healing continues to pose a challenge in clinical settings. Moreover, wound management must be performed properly and efficiently. Acute wound healing involves multiple cell divisions, a new extracellular matrix, and the process of formation, such as growth factors and cytokines, which are released at the site of the wound to regulate the process. Any changes that disrupt the healing process could cause tissue damage and prolong the healing process. Various factors, such as microbial infection, oxidation, and inflammation, can delay wound healing. In order to counter these problems, utilizing natural products with wound-healing effects has been reported to promote this process. A natural product with medicinal properties, which contribute to alleviating these factors, can facilitate the wound-healing process and be developed as a future drug. Numerous research has investigated the wound-healing properties of natural products that contain antioxidant, anti-inflammatory, collagen promotion, and antibacterial properties. Various phytochemicals, including alkaloids, tannins, flavonoids, terpenoids, phenolic, essential oils, and saponin compounds, may contribute to the medicinal effects. Natural products, including phytochemicals, play an important role in wound healing due to these properties. 
  • 835
  • 17 Jan 2023
Topic Review
Biochar Production and Properties
Biochar (BC) is the solid residue recovered from the thermal cracking of biomasses in an oxygen-poor atmosphere. BC has been increasingly explored as a sustainable, inexpensive, and viable alternative to traditional carbonaceous fillers for the development of polymer-based composites. In fact, BC exhibits high thermal stability, high surface area, and electrical conductivity; moreover, its main properties can be properly tuned by controlling the conditions of the production process.
  • 831
  • 08 Jul 2022
Topic Review
Effects of Bisphenol Analogs on Marine Species
Bisphenol A analogs are currently used in manufacturing and as plasticizers as a substitute for bisphenol A. This replacement is taking place because bisphenol A is recognized as an endocrine disruptor chemical (EDC) that can also cause oxidative stress and genotoxic effects in aquatic species. Bisphenol A analogs have a similar chemical structure to  bisphenol A (BPA), raising doubts about their use as safer substitutes.
  • 829
  • 27 Sep 2022
Topic Review
Berylliosis
Berylliosis, or chronic beryllium disease (CBD), is a chronic allergic-type lung response and chronic lung disease caused by exposure to beryllium and its compounds, a form of beryllium poisoning. It is distinct from acute beryllium poisoning, which became rare following occupational exposure limits established around 1950. Berylliosis is an occupational lung disease. While there is no cure, symptoms can be treated.
  • 825
  • 24 Oct 2022
Topic Review
Nickel Oxides
Nickel forms a series of mixed oxide compounds which are commonly called nickelates. A nickelate is an anion containing nickel or a salt containing a nickelate anion, or a double compound containing nickel bound to oxygen and other elements. Nickel can be in different or even mixed oxidation states, ranging from +1, +2, +3 to +4. The anions can contain a single nickel ion, or multiple to form a cluster ion. The solid mixed oxide compounds are often ceramics, but can also be metallic. They have a variety of electrical and magnetic properties. Rare-earth elements form a range of perovskite nickelates, in which the properties vary systematically as the rare-earth element changes. Fine tuning of properties is achievable with mixtures of elements, applying stress or pressure, or varying the physical form. Inorganic chemists call many compounds that contain nickel centred anions "nickelates". These include the chloronickelates, fluoronickelates, tetrabromonickelates, tetraiodonickelates, cyanonickelates, nitronickelates and other nickel-organic acid complexes such as oxalatonickelates.
  • 821
  • 10 Nov 2022
Topic Review
Immunosorbents Extracting Various Toxins
The evolution of instrumentation in terms of separation and detection allowed a real improvement of the sensitivity and analysis time. However, the analysis of ultra-traces of toxins in complex samples requires often a step of purification and even preconcentration before their chromatographic analysis. Therefore, immunoaffinity sorbents based on specific antibodies thus providing a molecular recognition mechanism appear as powerful tools for the selective extraction of a target molecule and its structural analogs to obtain more reliable and sensitive quantitative analysis in environmental, food or biological matrices.
  • 808
  • 24 Dec 2020
Topic Review
6-formyl-indolo(3,2-b)carbazole
6-formyl-indolo[3,2-b]carbazole (FICZ) (chemical formula C19H12N2O) is a nitrogen heterocycle, having an extremely high affinity (Kd = 7 x 10-11M) for binding to the Aryl hydrocarbon receptor (AhR). It was originally identified as a photooxidized derivative of the amino acid tryptophan and suggested to be the endogenous liagand of the AhR.
  • 808
  • 04 Nov 2022
Topic Review
Brassica Bioactives on Human Health
Brassica vegetables and their components, the glucosinolates, have been suggested as good candidates as dietary coadjutants to improve health in non-communicable diseases (NCDs).
  • 801
  • 12 Nov 2021
Topic Review
Eco-Friendly Colloidal Aqueous Sol-Gel Process
This entry reviews an eco-friendly process for producing TiO2 via colloidal aqueous sol–gel synthesis, resulting in crystalline materials without a calcination step. Three types of colloidal aqueous TiO2 are reviewed: the as-synthesized type obtained directly after synthesis, without any specific treatment; the calcined, obtained after a subsequent calcination step; and the hydrothermal, obtained after a specific autoclave treatment. This eco-friendly process is based on the hydrolysis of a Ti precursor in excess of water, followed by the peptization of the precipitated TiO2. Compared to classical TiO2 synthesis, this method results in crystalline TiO2 nanoparticles without any thermal treatment and uses only small amounts of organic chemicals. Depending on the synthesis parameters, the three crystalline phases of TiO2 (anatase, brookite, and rutile) can be obtained. The morphology of the nanoparticles can also be tailored by the synthesis parameters. The most important parameter is the peptizing agent. Indeed, depending on its acidic or basic character and also on its amount, it can modulate the crystallinity and morphology of TiO2. Colloidal aqueous TiO2 photocatalysts are mainly being used in various photocatalytic reactions for organic pollutant degradation. The as-synthesized materials seem to have equivalent photocatalytic efficiency to the photocatalysts post-treated with thermal treatments and the commercial Evonik Aeroxide P25, which is produced by a high-temperature process. Indeed, as-prepared, the TiO2 photocatalysts present a high specific surface area and crystalline phases. Emerging applications are also referenced, such as elaborating catalysts for fuel cells, nanocomposite drug delivery systems, or the inkjet printing of microstructures. Only a few works have explored these new properties, giving a lot of potential avenues for studying this eco-friendly TiO2 synthesis method for innovative implementations. 
  • 798
  • 28 Jun 2021
Topic Review
Innovative Approaches to Semi-Transparent Perovskite Solar Cells
Perovskite solar cells (PSCs) are advancing rapidly and have reached a performance comparable to that of silicon solar cells. They have been expanding into a variety of applications based on the excellent photoelectric properties of perovskite. Semi-transparent PSCs (ST-PSCs) are one promising application that utilizes the tunable transmittance of perovskite photoactive layers, which can be used in tandem solar cells (TSC) and building-integrated photovoltaics (BIPV). 
  • 797
  • 26 Apr 2023
Topic Review
Quinones as Promising Compounds against Respiratory Viruses
Respiratory viruses represent a world public health problem, giving rise to annual seasonal epidemics and several pandemics caused by some of these viruses, including the COVID-19 pandemic. Some antiviral drugs have been licensed for the treatment of influenza and respiratory syncytial virus, but they cause side effects, lead to resistant viral strains, or possess various limitations. On the other hand, no specific drugs are licensed to treat other viral respiratory diseases. In this sense, natural products have appeared as promising alternatives in searching for new compounds with antiviral activity. Quinones have demonstrated activity against respiratory viruses, so the activity of the different types of natural and synthetic quinones against these pathogens and their molecular targets are summarized.
  • 794
  • 20 Mar 2023
Topic Review
PI- based Optical Chemosensors
Perylene imide (PI) molecules and materials have been extensively studied for optical chemical sensors, particularly those based on fluorescence and colorimetric mode, taking advantage of the unique features of PIs such as structure tunability, good thermal, optical and chemical stability, strong electron affinity, strong visible light absorption and high fluorescence quantum yield. PIs-based optical chemosensors have now found broad applications in gas phase detection of chemicals, including explosives, biomarkers of some food and diseases (such as organic amines (alkylamines and aromatic amines)), benzene homologs, organic peroxides, phenols and nitroaromatics, etc.
  • 791
  • 12 Jan 2021
Topic Review
Ferroelectric Polymers
Ferroelectric polymers are a group of crystalline polar polymers that are also ferroelectric, meaning that they maintain a permanent electric polarization that can be reversed, or switched, in an external electric field. Ferroelectric polymers, such as polyvinylidene fluoride (PVDF), are used in acoustic transducers and electromechanical actuators because of their inherent piezoelectric response, and as heat sensors because of their inherent pyroelectric response. right|thumb|Figure 1: Structure of poly(vinylidene fluoride)
  • 786
  • 24 Oct 2022
Topic Review
Oxidative Stress and Human Ovarian Response
Oocyte quality is particularly sensitive to the metabolic endogenous and exogenous environment and a balanced signaling pathway between oxidant and antioxidant forces is fundamental for a proper follicular maturation. Women are born with a finite number of oocytes, and it is of key importance that the health of these oocytes is guaranteed throughout their reproductive life to ensure optimal ovulation, fertilization and subsequent embryonic development. The strategy by which the number and quality of oocytes can be preserved is the augmentation of systems capable of rapidly detecting and repairing DNA damage caused by a normal or abnormal metabolic status or by exposure to exogenous agents. Indeed, DNA damage repair is crucial for the integrity of the cellular genome and to its functionality. Noteworthily, for oocytes, it is essential to correct DNA damage in order to prevent the transmission of any genetic mutation to the offspring.
  • 780
  • 03 Aug 2022
Topic Review
Biogenic Sources of Synthesis of Nanoparticles
The green synthesis of NPs is employed by using plant extracts that offer a number of metabolites as reducing agents or capping agents, as well as the use of microbes as green nanofactories to tackle the issue of water cleanliness with respect to pharmaceutical waste. The concepts and principles of green chemistry were first presented by two scientists named Anastas and Warner. For green synthesis of NPs, the selection of solvent and reducing/stabilizing agent is of great significance and often governs the morphologies and size of NPs. Different types of green synthesis methods can be used depending upon the nature of the source of reducing or stabilizing agents, such as plants, algae, vitamins, etc., from which extracts can be collected. The forthcoming sections discuss the various routes utilized for green synthesis of photocatalysts employed in drug degradation.
  • 763
  • 07 Mar 2023
Topic Review
Four-Dimensional Printing of Dynamic Foods
The continuous evolution of 3D food printing in the used methods, approaches, and materials has created a solid foundation for technology to process dynamic food structures. In 4D food printing, structures are engineered through material tailoring and custom designs to achieve a transformation from one configuration to another. Different engineered 4D behaviors include stimulated color change, shape morphing, and biological growth.
  • 759
  • 30 Nov 2023
Topic Review
Melatonin Receptor
Melatonin receptors are G protein-coupled receptors (GPCR) which bind melatonin. Three types of melatonin receptors have been cloned. The MT1 (or Mel1A or MTNR1A) and MT2 (or Mel1B or MTNR1B) receptor subtypes are present in humans and other mammals, while an additional melatonin receptor subtype MT3 (or Mel1C or MTNR1C) has been identified in amphibia and birds. The receptors are crucial in the signal cascade of melatonin. In the field of chronobiology, melatonin has been found to be a key player in the synchrony of biological clocks. Melatonin secretion by the pineal gland has circadian rhythmicity regulated by the suprachiasmatic nucleus (SCN) found in the brain. The SCN functions as the timing regulator for melatonin; melatonin then follows a feedback loop to decrease SCN neuronal firing. The receptors MT1 and MT2 control this process. Melatonin receptors are found throughout the body in places such as the brain, the retina of the eye, the cardiovascular system, the liver and gallbladder, the colon, the skin, the kidneys, and many others. In 2019, X-ray crystal and cryo-EM structures of MT1 and MT2 were reported.
  • 737
  • 21 Oct 2022
Topic Review
Light-Driven Semiconductor-Based Micro/Nanomotors
Micro/nanomotors represent a burgeoning field of research featuring small devices capable of autonomous movement in liquid environments through catalytic reactions and/or external stimuli.
  • 737
  • 18 Mar 2024
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