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Topic Review
Chemical Properties of Calcium Phosphate
 Calcium phosphate (CaP)-based biomaterials have superior properties and have been widely used for bone defect repair, due to their similarities to the inorganic components of human bones. The biological performance of CaPs, as a determining factor for their applications, are dependent on their physicochemical properties. Hydroxyapatite (HAP) as the most thermally stable crystalline phase of CaP is mostly used in the form of ceramics or composites scaffolds with polymers. Nanostructured CaPs with large surface areas are suitable for drug/gene delivery systems. CaP is not only a family of natural minerals, but also includes biominerals in humans, which are the main inorganic component of hard tissue (bone and teeth).
  • 1.3K
  • 27 Oct 2022
Topic Review
Magnetorheological Elastomers
Magnetorheological elastomers (MREs) are magneto-sensitive smart materials, widely used in various applications, i.e., construction, automotive, electrics, electronics, medical, minimally invasive surgery, and robotics. Such a wide field of applications is due to their superior properties, including morphological, dynamic mechanical, magnetorheological, thermal, friction and wear, and complex torsional properties.
  • 1.3K
  • 28 Dec 2020
Topic Review
Egyptian Honeybee
The Egyptian honeybee (Apis mellifera lamarckii) is one of the honeybee subspecies known for centuries since the ancient Egypt civilization. The subspecies of the Egyptian honeybee is distinguished by certain traits of appearance and behavior that were well-adapted to the environment and unique in a way that it is resistant to bee diseases, such as the Varroa disease. The subspecies is different than those found in Europe and is native to southern Egypt.
  • 1.2K
  • 21 Oct 2022
Topic Review
Coumarin(Benzopyrone)-Fused Five-Membered Aromatic Heterocycles
Coumarins are a family of benzopyrones (1,2-benzopyrones or 2H-[1]benzopyran-2-ones), which represent an important family of oxygen-containing heterocycles, widely distributed in nature. Since coumarins have versatile applications, the synthesis trials of different structures of the coumarin-based scaffold were attempted. Among all the heterocycles built on α-pyrone moiety of coumarin, the furan ring was the only available structure in nature. Thus, it has inspired a lot of researchers to replace the oxygen with other heteroatoms. Wide varieties of heterocycles were constructed by a synthetic pathway to introduced furans, pyrroles, thiophenes, and selenophenes as a fused ring that characterized by a single heteroatom to the α-pyrone moiety of coumarin. 
  • 1.2K
  • 05 Apr 2021
Topic Review
Honey for Antimicrobial and Wound Healing Applications
Honey was used in traditional medicine to treat wounds until the advent of modern medicine. The rising global antibiotic resistance has forced the development of novel therapies as alternatives to combat infections. Consequently, honey is experiencing a resurgence in evaluation for antimicrobial and wound healing applications. A range of both Gram-positive and Gram-negative bacteria, including antibiotic-resistant strains and biofilms, are inhibited by honey. Furthermore, susceptibility to antibiotics can be restored when used synergistically with honey. Honey’s antimicrobial activity also includes antifungal and antiviral properties, and in most varieties of honey, its activity is attributed to the enzymatic generation of hydrogen peroxide, a reactive oxygen species. Non-peroxide factors include low water activity, acidity, phenolic content, defensin-1, and methylglyoxal (Leptospermum honeys). Honey has also been widely explored as a tissue-regenerative agent. It can contribute to all stages of wound healing, and thus has been used in direct application and in dressings. The difficulty of the sustained delivery of honey’s active ingredients to the wound site has driven the development of tissue engineering approaches (e.g., electrospinning and hydrogels). 
  • 1.2K
  • 29 Aug 2022
Topic Review
Synthetic methods of phosphonopeptides
Phosphonopeptides are phosphorus analogues of peptides and have been widely applied as enzyme inhibitors and antigens to induce catalytic antibodies. Phosphonopeptides generally contain one aminoalkylphosphonic acid residue and include phosphonopeptides with C-terminal aminoalkylphosphonic acids and phosphonopeptides with a phosphonamidate bond. The phosphonamidate bond in the phosphonopeptides is generally formed via phosphonylation with phosphonochloridates, condensation with coupling reagents and enzymes, and phosphinylation followed by oxidation. Pseudo four-component condensation reaction of amides, aldehydes, alkyl dichlorophosphites, and amino/peptide esters is an alternative, convergent, and efficient strategy for synthesis of phosphonopeptides through simultaneous construction of aminoalkylphosphonic acids and formation of the phosphonamidate bond.
  • 1.2K
  • 16 Dec 2020
Topic Review
Chitin and Chitosan
Chitin and its derivative chitosan are highly abundant polymers in nature, appearing in both the shells and exoskeletons of various marine and non-marine species. Since they possess favorable properties, such as biocompatibility, biodegradability, non-toxicity, and non-immunogenicity, they have gained recent attention due to their enormous potential biomedical applications. The polycationic surface of chitosan enables it to form hydrogenic and ionic bonds with drug molecules, which is one of its most useful properties. Because chitosan is biocompatible, it can therefore be used in drug delivery systems. The development of chitosan-based nanoparticles has also contributed to the significance of chitin as a drug delivery system that can deliver drugs topically. Furthermore, chitin can be used in cancer treatment as a vehicle for delivering cancer drugs to a specific site and has an antiproliferative effect by reducing the viability of cells. Finally, chitosan can be used as a wound dressing in order to promote the faster regeneration of skin epithelial cells and collagen production by fibroblasts.
  • 1.2K
  • 01 Aug 2022
Topic Review
Zinc Coating
Advanced high strength galvanized steel sheet has been one of the dominant materials of modern automotive panels because of its outstanding mechanical properties and corrosion resistance. The zinc coating thickness of hot dip galvanized steel sheet is only about 10–20μm, which is a discarded object on the macro level. However, it is obvious to damage and impact on stamping performance. Therefore, this work takes zinc coating as the research object and builds its mechanical constitutive model based on a nano-indentation test and dimensional analysis theory. We separated the zinc coating from the galvanized steel substrate and constructed a sandwich material model by introducing a cohesive layer to connect the zinc coating and the steel substrate. We obtained the interface binding energy between the zinc coating and the steel substrate through the nano-scratch test. The accuracy of the model is verified by the finite element analysis of hemispherical parts. We used the five-layers element model with 0 thickness cohesive layer to simulate the zinc coating damage of galvanized steel sheet. The hemispherical part drawing experiment is used to verify the feasibility of the finite element analysis results. The results demonstrate that it is more accurate to consider the finite element numerical simulation of the zinc coating, introducing the cohesive element to simulate damage between the coating and the substrate. Drawing depth, stamping force, and the strain of the numerical simulation are closer to the experimental results.
  • 1.2K
  • 01 Nov 2020
Topic Review
Directed Self-Assembly of Block Copolymers
Directed self-assembly (DSA) of block copolymers (BCPs) is a bottom-up approach to nanofabrication based on the ability of BCPs to phase separate spontaneously. It is an attractive technique for the fabrication of nanoscale structures thanks to its high resolution, low cost, ease of integration and scalability.
  • 1.2K
  • 16 Jun 2021
Topic Review
Zirconolite and Murataite for the Immobilization of Actinides
Zirconolite is highly stable in nature, with isotope systems that have been closed for hundreds of million years, making it possible for age determination. Murataite is a very rare mineral, its synthetic counerpart was first discovered in the Synroc matrix from defense waste obtained by sintering. Synthetic zirconolie and murataite can be applied for nuclear waste immobilization. 
  • 1.2K
  • 14 Sep 2022
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