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Topic Review
Surface-Enhanced Raman Scattering
The efficiency of the generation of Raman spectra by molecules adsorbed on some substrates (or placed at a very close distance to some substrates) may be many orders of magnitude larger than the efficiency of the generation of Raman spectra by molecules that are not adsorbed. This effect is called surface-enhanced Raman scattering (SERS). In the first SERS experiments, nanostructured plasmonic metals have been used as SERS-active materials. Later, other types of SERS-active materials have also been developed.
  • 1.1K
  • 10 Feb 2021
Topic Review
Coatings for Milling
This entry talks a little about the development and application of PVD and CVD coatings on machining tools.
  • 1.1K
  • 05 Nov 2020
Topic Review
Enantioselective Catalytic C-H Amidations
The crucial role played by compounds bearing amide functions, not only in biological processes but also in several fields of chemistry, life polymers and material sciences, has brought about many significant discoveries and innovative approaches for their chemical synthesis. Within this context, and following the development of C-H functionalization strategies, C-H amidation reactions have only recently emerged as valuable approaches for the construction of amide functions. These methodologies have been successfully used for both C(sp2)- and C(sp3)-H activations and blossoming synthetic applications have appeared in the last two years (2019-2020 timeframe).
  • 1.1K
  • 15 Apr 2021
Topic Review
Peptide Applications Using Microfluidics
Peptides possess multifunctional roles within therapeutic formulations, ranging from enhancing target specificity to acting as the active component of the medicine. By applying the platform of microfluidics, the range of applications for peptides has been seen to rise exponentially. Various therapeutic applications of peptides are listed in this review.
  • 1.1K
  • 11 May 2021
Topic Review
Chemical-based Methodologies for Fresh Fish Shelf-Life Extension
Due to its characteristics, fresh fish is a highly perishable food with a very short shelf-life under refrigeration. Several methods have been introduced to slow down its deterioration, such as by means of oxygen depletion of the food package (vacuum packaging), or by changing the natural atmosphere that is in contact with the fresh fish (modified atmosphere packaging), or by the use of chemicals generally recognized as safe: such compounds can be directly applied (by dipping or spraying) or incorporated into packaging materials and slowly migrate to the product, exerting a hurdle effect against microbial development and lipid oxidation (active packaging).
  • 1.1K
  • 22 Oct 2021
Topic Review
Benzodiazepine Use Disorder
Benzodiazepine use disorder (BUD), also called misuse or abuse, is the use of benzodiazepines without a prescription, often for recreational purposes, which poses risks of dependence, withdrawal and other long-term effects. Benzodiazepines are one of the more common prescription drugs used recreationally. When used recreationally benzodiazepines are usually administered orally but sometimes they are taken intranasally or intravenously. Recreational use produces effects similar to alcohol intoxication. In tests in pentobarbital trained rhesus monkeys benzodiazepines produced effects similar to barbiturates. In a 1991 study, triazolam had the highest self-administration rate in cocaine trained baboons, among the five benzodiazepines examined: alprazolam, bromazepam, chlordiazepoxide, lorazepam, triazolam. A 1985 study found that triazolam and temazepam maintained higher rates of self-injection in both human and animal subjects compared to a variety of other benzodiazepines (others examined: diazepam, lorazepam, oxazepam, flurazepam, alprazolam, chlordiazepoxide, clonazepam, nitrazepam, flunitrazepam, bromazepam, and clorazepate). A 1991 study indicated that diazepam, in particular, had a greater abuse liability among people who were drug abusers than did many of the other benzodiazepines. Some of the available data also suggested that lorazepam and alprazolam are more diazepam-like in having relatively high abuse liability, while oxazepam, halazepam, and possibly chlordiazepoxide, are relatively low in this regard. A 1991–1993 British study found that the hypnotics flurazepam and temazepam were more toxic than average benzodiazepines in overdose. A 1995 study found that temazepam is more rapidly absorbed and oxazepam is more slowly absorbed than most other benzodiazepines. Benzodiazepines have been abused both orally and intravenously. Different benzodiazepines have different abuse potential; the more rapid the increase in the plasma level following ingestion, the greater the intoxicating effect and the more open to abuse the drug becomes. The speed of onset of action of a particular benzodiazepine correlates well with the 'popularity' of that drug for abuse. The two most common reasons for preference were that a benzodiazepine was 'strong' and that it gave a good 'high'. According to Dr. Chris Ford, former clinical director of Substance Misuse Management in General Practice, among drugs of abuse, benzodiazepines are often seen as the 'bad guys' by drug and alcohol workers. Illicit users of benzodiazepines have been found to take higher methadone doses, as well as showing more HIV/HCV risk-taking behavior, greater poly-drug use, higher levels of psychopathology and social dysfunction. However, there is only limited research into the adverse effects of benzodiazepines in drug misusers and further research is needed to demonstrate whether this is the result of cause or effect.
  • 1.1K
  • 18 Oct 2022
Topic Review
High Performance Bioplastics
Biomass provides a wealth of renewable and bio-waste resources for bioplastics synthesis. Many of these bio-based plastics, encompass capacities for biodegradation and bioprocessing with high performance features akin to petroleum-based plastics. The realisation of bioplastics that exhibit a complete set of mechanical and biodegradability, hold the promise of delivering material of ecologically sustainable, low carbon footprint circularity.
  • 1.1K
  • 14 Jul 2021
Topic Review
Photodynamic Therapy for Deep-Seated Tumors
Photodynamic therapy (PDT) works through the photoactivation of a specific photosensitizer (PS) in a tumor in the presence of oxygen. PDT is widely applied in oncology to treat various cancers as it has a minimally invasive procedure and high selectivity, does not interfere with other treatments, and can be repeated as needed. A large amount of reactive oxygen species (ROS) and singlet oxygen is generated in a cancer cell during PDT, which destroys the tumor effectively. However, the efficacy of PDT in treating a deep-seated tumor is limited due to three main reasons: Limited light penetration depth, the low oxygen concentration in the hypoxic core, and poor PS accumulation inside a tumor. Thus, PDT treatments are only approved for superficial and thin tumors. With the advancement of nanotechnology, PDT to treat deep-seated or thick tumors is becoming a reachable goal. In this review, we provide an update on the strategies for improving PDT with nanomedicine using different sophisticated-design nanoparticles, including two-photon excitation, X-ray activation, targeting tumor cells with surface modification, alteration of tumor cell metabolism pathways, the release of therapeutic gases, improvement of tumor hypoxia, and stimulation of host immunity.
  • 1.1K
  • 11 Oct 2021
Topic Review
Interaction of Water and Solutes
Water plays an important role in chemical and biological processes. The interaction of water and solutes is of great significance for understanding the properties of aqueous solutions or bio-systems.
  • 1.1K
  • 08 Feb 2022
Topic Review
Heating's Influence Trans Fatty Acid in Oils
Consumption of trans fatty acids (TFA) is associated with adverse health outcomes and places a considerable burden on morbidity and mortality globally. TFA may be generated by common cooking practices and hence contribute to daily dietary intake. Heating edible oils to common cooking temperatures (≤200 °C) has minimal effect on TFA generation whereas heating to higher temperatures can increase TFA level. 
  • 1.1K
  • 24 May 2022
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