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Topic Review
Hydrogen Sources in Catalytic Transfer Hydrogenation
Catalytic transfer hydrogenation has emerged as a pivotal chemical process with transformative potential in various industries. Unlike conventional direct hydrogenation, catalytic transfer hydrogenation offers numerous advantages, such as enhanced safety, cost-effective hydrogen donors, byproduct recyclability, catalyst accessibility, and the potential for catalytic asymmetric transfer hydrogenation, particularly with chiral ligands. Alcohols such as methanol and isopropanol are prominent hydrogen donors, demonstrating remarkable efficacy in various reductions. Formic acid offers irreversible hydrogenation, preventing the occurrence of reverse reactions, and is extensively utilized in chiral compound synthesis. Unconventional donors such as 1,4-cyclohexadiene and glycerol have shown a good efficiency in reducing unsaturated compounds, with glycerol additionally serving as a green solvent in some transformations. 
  • 849
  • 14 Nov 2023
Topic Review
Bone Fragility
Bone material strength is determined by several factors, such as bone mass, matrix composition, mineralization, architecture and shape. From a clinical perspective, bone fragility is classified as primary (i.e., genetic and rare) or secondary (i.e., acquired and common) osteoporosis
  • 849
  • 02 Feb 2021
Topic Review
Microcellular Injection Moulding
Microcellular injection moulding (MuCell®) is a polymer processing technology that uses a supercritical fluid inert gas, CO2 or N2, to produce light-weight products. Due to environmental pressures and the requirement of light-weight parts with good mechanical properties, this technology recently gained significant attention. However, poor surface appearance and limited mechanical properties still prevent the wide applications of this technique.
  • 849
  • 16 Aug 2021
Topic Review
MXene–Metal Composites
MXene, an advanced family of 2D ceramic material resembling graphene, has had a considerable impact on the field of research because of its unique physiochemical properties. MXene has been synthesized by the selective etching of MAX via different techniques. However, with the passage of time, due to the need for further progress and improvement in MXene materials, ideas have turned toward composite fabrication, which has aided boosting the MXene composites regarding their properties and applications in various areas.
  • 849
  • 27 Apr 2022
Topic Review
Camelids' Milk
Camel milk has always represented an important food for nomadic people in the arid parts of the world; recently, camel milk attracted great attention as a possible replacer to dairy cow’s milk because of its therapeutic effects. The use of alternative milk for feeding children can be effective in reducing the development of gastrointestinal disorders.
  • 849
  • 19 Apr 2022
Topic Review
Aflatoxin
Aflatoxins are poisonous carcinogens that are produced by certain molds (Aspergillus flavus and Aspergillus parasiticus) which grow in soil, decaying vegetation, hay, and grains. They are regularly found in improperly stored staple commodities such as cassava, chili peppers, corn, cotton seed, millet, peanuts, rice, sesame seeds, sorghum, sunflower seeds, tree nuts, wheat, and a variety of spices. When contaminated food is processed, aflatoxins enter the general food supply where they have been found in both pet and human foods, as well as in feedstocks for agricultural animals. Animals fed contaminated food can pass aflatoxin transformation products into eggs, milk products, and meat. For example, contaminated poultry feed is suspected in the findings of high percentages of samples of aflatoxin-contaminated chicken meat and eggs in Pakistan. Children are particularly affected by aflatoxin exposure, which is associated with stunted growth, delayed development, liver damage, and liver cancer. An association between childhood stunting and aflatoxin exposure has been reported in some studies but could not be detected in all. Furthermore, a causal relationship between childhood stunting and aflatoxin exposure has yet to be conclusively shown by epidemiological studies, though such investigations are underway. Adults have a higher tolerance to exposure, but are also at risk. No animal species is immune. Aflatoxins are among the most carcinogenic substances known. After entering the body, aflatoxins may be metabolized by the liver to a reactive epoxide intermediate or hydroxylated to become the less harmful aflatoxin M1. Aflatoxins are most commonly ingested. However the most toxic type of aflatoxin, B1, can permeate through the skin. The United States Food and Drug Administration (FDA) action levels for aflatoxin present in food or feed is 20 to 300 ppb. The FDA has had occasion to declare both human and pet food recalls as a precautionary measure to prevent exposure. The term "aflatoxin" is derived from the name of one of the molds that produce it, Aspergillus flavus. It was coined around 1960 after its discovery as the source of "Turkey X disease". Aflatoxins form one of the major groupings of mycotoxins.
  • 849
  • 28 Oct 2022
Topic Review
Nanomaterials in Cell-Based Drug Delivery Systems
The combination of nanomaterials with cell-based drug delivery systems has shown tremendous advantages in cancer treatment.
  • 849
  • 29 Mar 2022
Topic Review
Carbon-Based Nanomaterials for Bone Regeneration
This work explores the potential research opportunities and challenges of 3D printed biodegradable composite-based scaffolds containing carbon-based nanomaterials for bone tissue engineering applications. Bone possesses an inherent capacity to fix itself. However, when a defect larger than a critical size appears, external solutions must be applied. Traditionally, autograft has been the most used solution in these situations. However, it presents some issues such as donor-site morbidity. In this context, porous biodegradable scaffolds have emerged as an interesting solution. For adequate performance, these scaffolds must meet specific requirements: biocompatibility, interconnected porosity, mechanical properties, and biodegradability. The development of additive manufacturing methods has proposed a promising solution for this application since they allow the complete customization and control of scaffolds geometry and porosity. Furthermore, carbon-based nanomaterials present the potential to impart osteoconductivity and antimicrobial properties and reinforce the matrix from a mechanical perspective. These properties make them ideal for use as nanomaterials to improve the properties and performance of scaffolds for bone tissue engineering. 
  • 848
  • 09 Dec 2020
Topic Review
Advancements in Natural Dyes Extraction
The dyeing and finishing step represents a clear hotspot in the textile supply chain as the wet processing stages require significant amounts of water, energy, and chemicals. In order to tackle environmental issues, natural dyes are gaining attention from researchers as more sustainable alternatives to synthetic ones. The extraction of colorant from natural sources is a fundamental step in preparing purified natural dyes, as a plant’s matrix contains only a small percentage of dye, usually in the range of 0.5–5%, and several other constituents such as water-insoluble fibers, carbohydrates, protein, chlorophyll, and tannins, among others. The selection of the most suitable extraction technique should be based on the evaluation of the nature and solubility of the dyeing materials.
  • 847
  • 28 Aug 2023
Topic Review
CDs as Antimicrobial Agents
Carbon dots (CDs) have been identified as a promising class of photosensitiser nanomaterials for the specific detection and inactivation of different bacterial species. CDs possess exceptional and tuneable chemical and photoelectric properties that make them excellent candidates for antibacterial theranostic applications, such as great chemical stability, high water solubility, low toxicity and excellent biocompatibility. 
  • 847
  • 29 Jul 2021
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