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Topic Review
Proinsulin
Proinsulin is the prohormone precursor to insulin made in the beta cells of the islets of Langerhans, specialized regions of the pancreas. In humans, proinsulin is encoded by the INS gene. The islets of Langerhans only secrete between 1% and 3% of proinsulin intact. However, because proinsulin has a longer half life than insulin, it can account for anywhere from 5–30% of the insulin-like structures circulating in the blood. There are higher concentrations of proinsulin after meals and lower levels when a person is fasting. Additionally, while proinsulin and insulin have structural differences, proinsulin does demonstrate some affinity for the insulin receptor. Due to the relative similarities in structure, proinsulin can produce between 5% and 10% of the metabolic activity similarly induced by insulin. Proinsulin is the final single chain protein structure secreted by cells before cleavage into mature insulin. Proinsulin was discovered by Professor Donald F. Steiner of the University of Chicago in 1967.
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  • 24 Nov 2022
Topic Review
Β-lactam Antibiotic
β-lactam antibiotics (beta-lactam antibiotics) are antibiotics that contain a beta-lactam ring in their molecular structure. This includes penicillin derivatives (penams), cephalosporins and cephamycins (cephems), monobactams, carbapenems and carbacephems. Most β-lactam antibiotics work by inhibiting cell wall biosynthesis in the bacterial organism and are the most widely used group of antibiotics. Until 2003, when measured by sales, more than half of all commercially available antibiotics in use were β-lactam compounds. The first β-lactam antibiotic discovered, penicillin, was isolated from a rare variant of Penicillium notatum (since renamed Penicillium chrysogenum). Bacteria often develop resistance to β-lactam antibiotics by synthesizing a β-lactamase, an enzyme that attacks the β-lactam ring. To overcome this resistance, β-lactam antibiotics can be given with β-lactamase inhibitors such as clavulanic acid.
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Topic Review
Fiber Attrition and Micro-Voids
A discontinuous fiber-reinforced polymer composite (DFRPC) provides superior mechanical performances in material extrusion additive manufacturing (MEAM) parts, and thus promotes their implementations in engineering applications. The process-induced structural defects of DFRPCs increase the probability of pre-mature failures as the manufactured parts experience complicated external loads. The process-induced fiber length attrition and micro-voids formations in MEAM applications is provided. By gaining a clearer view of the correlations between the MEAM processing parameters, and tooling and the resulting microstructures of produced DFRPCs, it is expected to manufacture composites parts with more preferable mechanical properties via MEAM.
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Topic Review
Applications of Proteinaceous Nanotube Cavities in Nanotechnology
Nanotechnology is quickly evolving, with novel materials being produced on a rapid scale. These nanomaterials range from fibers and sheets to tubular designs that are based on various different compositions such as metallic or carbon-based materials. In particular, carbon-based nanotubes, which include single- and multiwall tubes, have found applications in many scientific fields such as medicine, energy storage and fuel cells. Adding to these are the advances made with protein-based nanotubes, which offer different properties from those of classical carbon-based nanotubes. Although it would seem that biologically based nanotubes offer little room for direct design, current studies have shown that the high complexity of proteins can be an advantage for biotechnological designs that offers a novel perspective on many applications.
  • 409
  • 24 Nov 2022
Topic Review
Sulfonamide
Sulfonamide is a functional group (a part of a molecule) that is the basis of several groups of drugs, which are called sulphonamides, sulfa drugs or sulpha drugs. The original antibacterial sulfonamides are synthetic (nonantibiotic) antimicrobial agents that contain the sulfonamide group. Some sulfonamides are also devoid of antibacterial activity, e.g., the anticonvulsant sultiame. The sulfonylureas and thiazide diuretics are newer drug groups based upon the antibacterial sulfonamides. Allergies to sulfonamides are common. The overall incidence of adverse drug reactions to sulfa antibiotics is approximately 3%, close to penicillin; hence medications containing sulfonamides are prescribed carefully. Sulfonamide drugs were the first broadly effective antibacterials to be used systemically, and paved the way for the antibiotic revolution in medicine.
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  • 23 Nov 2022
Topic Review
Vortex Pinning Centers in High-Temperature Superconducting Films
To better pin the vortex at external magnetic fields, the HTS films must contain APCs with desired morphology, dimension, orientation, and concentration. Nanoscale APCs with lateral dimension approaching 2ξ (coherence length) on the order of a few nanometers in HTSs must be generated to suppress the dissipation of vortex motion. This has prompted extensive efforts and exciting results have been obtained in generating nanoscale APCs in HTS films. The research progress of different types and dimensions APCs in detail is introduced and the impact on superconducting performance is summarized.
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Topic Review
Advantages on Waste Management in Hydrogen Industry
The turn to hydrogen as an energy source is a fundamentally important task facing the global energetics, aviation and automotive industries. This step would reduce the negative man-made impact on the environment on the one hand, and provide previously inaccessible power modes and increased resources for technical systems, predetermining the development of an absolutely new life cycle for important areas of technology, on the other. The most important aspect in this case is the development of next-generation technologies for hydrogen industry waste management that will definitely reduce the negative impact of technology on the environment. 
  • 599
  • 23 Nov 2022
Topic Review
Solid-State Polymer Electrolytes for Lithium Batteries
In all-solid-state rechargeable lithium batteries, the solid-state electrolyte is located between the cathode and the anode, acting as an electrolyte and a separator, so the performance of the solid-state electrolyte is crucial to the performance of the entire battery.
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  • 23 Nov 2022
Topic Review
Phytochemicals Used for Hair Dyeing
Natural dyes have been used since ancient times, when they were used not only for hair coloration, but also for medicinal, decoration and religious purposes. Many organic compounds have been identified as the principal coloring matters in hair dye plants and investigated for dyeing performance under experimental conditions. Natural colorants can be classified based on dye source, application method and chemical structure.
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  • 23 Nov 2022
Biography
Matthew H. Todd
Matthew Houghton Todd (born 13 January 1973) is a British chemist and the Professor and Chair of Drug Discovery of the School of Pharmacy at University College London.[1] He is the founder of Open Source Malaria (OSM) and his research focuses on drug discovery and development for this disease.[2][3][4][5][6] Recently, he has expanded to other areas, particularly neglected diseases such as tuberc
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  • 23 Nov 2022
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