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Topic Review
BPA Controversy
Bisphenol A controversy centers on concerns and debates about the biomedical significance of bisphenol A (BPA), which is a precursor to polymers that are used in some consumer products, including some food containers. The concerns began with the hypothesis that BPA is an endocrine disruptor, i.e. it mimics endocrine hormones and thus has the unintended and possibly far-reaching effects on people in physical contact with the chemical. Since 2008, several governments have investigated its safety, which prompted some retailers to withdraw polycarbonate products. The U.S. Food and Drug Administration (FDA) ended its authorization of the use of BPA in baby bottles and infant formula packaging, based on market abandonment, not safety. The European Union and Canada have banned BPA use in baby bottles. The U.S. FDA states "BPA is safe at the current levels occurring in foods" based on extensive research, including two more studies issued by the agency in early 2014. The European Food Safety Authority (EFSA) reviewed new scientific information on BPA in 2008, 2009, 2010, 2011 and 2015: EFSA's experts concluded on each occasion that they could not identify any new evidence which would lead them to revise their opinion that the known level of exposure to BPA is safe; however, the EFSA does recognize some uncertainties, and will continue to investigate them. In February 2016, France announced that it intends to propose BPA as a REACH Regulation candidate substance of very high concern (SVHC). The European Chemicals Agency agreed to the proposal in June 2017.
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  • 11 Oct 2022
Topic Review
Carbon Capture and Storage (Timeline)
The milestones for carbon capture and storage show the lack of commercial scale development and implementation of CCS over the years since the first carbon tax was imposed. The time line of carbon capture and storage announcements and developments follows:
  • 601
  • 11 Oct 2022
Topic Review
PRC200
PRC200-SS is an arylalkanolamine TRI being developed by the Mayo Clinic. Sympathomimetic PRC200-SS is the PRC050 eutomer, whereas PRC201 is the distomer. These compounds are preceded by venlafaxine, which Wyeth claims is the first SNRI. Venlafaxine was originally developed as an "opioid" although original screening returned negative results. The authors were not satisfied just to drop venlafaxine from development and continued with their study of the compounds biological activity data. Herein, they discovered that venlafaxine exerts its biological actions via interaction with the monoamine receptors. In particular, the actions of the drug on increasing the amount of 5-HT and NE were documented, although with "potentiated" analogs such as the pm-dichlorophenyl ring substituted derivative, it might be expected to behave as a SNDRI also (but no data was available to support this inference). Venlafaxine itself has been said to behave as a SNDRI at very high doses. This would be more likely to be the case in drug naïve subjects than in users that have already built up significant tolerance. Silicon containing analog of venlafaxine was prepared and demonstrated to be an active SNRI.
  • 292
  • 11 Oct 2022
Topic Review
Composite Repairs
Composite repairs. Composite materials are used in a wide range of applications in aerospace, marine, automotive, surface transport and sports equipment markets. Damage to composite components is not always visible to the naked eye and the extent of damage is best determined for structural components by suitable Non Destructive Test (NDT) methods. The concept for composite repair of composite or metallic structures is simple. The bonded repair reduces stresses in the damaged region and keeps the cracks from opening and therefore from growing.
  • 842
  • 11 Oct 2022
Topic Review
Membrane-Based Biogas and Biohydrogen Upgrading
Biogas and biohydrogen, due to their renewable nature and zero carbon footprint, are considered two of the gaseous biofuels that will replace conventional fossil fuels. Biogas from anaerobic digestion must be purified and converted into high-quality biomethane prior to use as a vehicle fuel or injection into natural gas networks.
  • 451
  • 11 Oct 2022
Topic Review
Reactive Species-Activatable AIEgens for Biomedical Applications
Precision medicine requires highly sensitive and specific diagnostic strategies with high spatiotemporal resolution. Accurate detection and monitoring of endogenously generated biomarkers at the very early disease stage is of extensive importance for precise diagnosis and treatment. Aggregation-induced emission luminogens (AIEgens) have emerged as a new type of excellent optical agents, which show great promise for numerous biomedical applications. Advances of AIE-based probes for detecting reactive species (including reactive oxygen species (ROS), reactive nitrogen species (RNS), reactive sulfur species (RSS), and reactive carbonyl species (RCS)) and related biomedical applications are introduced. The molecular design strategies for increasing the sensitivity, tuning the response wavelength, and realizing afterglow imaging are summarized, and theranostic applications in reactive species-related major diseases such as cancer, inflammation, and vascular diseases are reviewed.
  • 274
  • 11 Oct 2022
Topic Review
Enzyme Crosslinking Approaches for Bone Tissue Engineering
Crosslinking strategies have been extensively explored in order to design novel hydrogels for bone tissue engineering. Lately, the fabrication of hydrogels with the help of enzyme-mediated crosslinking approaches has been extensively explored. This approach has resulted in promising outcomes with convincing prospects. Enzymes are required in minimal quantity and are very efficient in their actions, as they increase the reaction rate without being expended during the course of the reaction process. The efficiency of an enzyme is defined by the number of substrate molecules converted into products per unit of enzyme, which is also known as turnover number (k cat). The high efficiency of enzyme-based reactions comes from the precise specificity, which ensures the conversion of a particular type of substrate to products. Many enzymes have been explored in order to prepare biomimetic hydrogels for bone tissue engineering. The details of every enzyme-based crosslinking approach are discussed in the following sections.
  • 540
  • 11 Oct 2022
Topic Review
Hyperchloremia
Hyperchloremia is an electrolyte disturbance in which there is an elevated level of chloride ions in the blood. The normal serum range for chloride is 96 to 106 mEq/L, therefore chloride levels at or above 110 mEq/L usually indicate kidney dysfunction as it is a regulator of chloride concentration. As of now there are no specific symptoms of hyperchloremia; however, it can be influenced by multiple abnormalities that cause a loss of electrolyte-free fluid, loss of hypotonic fluid, or increased administration of sodium chloride. These abnormalities are caused by diarrhea, vomiting, increased sodium chloride intake, renal dysfunction, diuretic use, and diabetes. Hyperchloremia should not be mistaken for hyperchloremic metabolic acidosis as hyperchloremic metabolic acidosis is characterized by two major changes: a decrease in blood pH and bicarbonate levels, as well as an increase in blood chloride levels. Instead those with hyperchloremic metabolic acidosis are usually predisposed to hyperchloremia. Hyperchloremia prevalence in hospital settings has been researched in the medical field since one of the major sources of treatment at hospitals is administering saline solution. Previously, animal models with elevated chloride have displayed more inflammation markers, changes in blood pressure, increased renal vasoconstriction, and less renal blood flow as well at glomerulus filtration, all of which are prompting researchers to investigate if these changes or others may exist in patients. Some studies have reported a possible relationship between increased chloride levels and death or acute kidney injury in severely ill patients that may frequent the hospital or have prolonged visits. There are other studies that have found no relationship. As studies continue, it is important to include a large patient sample size, a diverse patient population, and a diverse range of hospitals involved in these studies.
  • 707
  • 11 Oct 2022
Topic Review
Dispersion
A dispersion is a system in which distributed particles of one material are dispersed in a continuous phase of another material. The two phases may be in the same or different states of matter. Dispersions are classified in a number of different ways, including how large the particles are in relation to the particles of the continuous phase, whether or not precipitation occurs, and the presence of Brownian motion. In general, dispersions of particles sufficiently large for sedimentation are called suspensions, while those of smaller particles are called colloids and solutions.
  • 1.1K
  • 11 Oct 2022
Topic Review
Protective Coatings for ATF Claddings
Since 2011, following the tragic Fukushima Daiichi Nuclear accident, great attention has been devoted to the development of a new concept of nuclear fuel to improve the safety of nuclear reactors during normal operation, transient modes and under accident conditions. A concept called “accident tolerant fuel (ATF)” indicates a strategy to prevent/limit the interaction of cladding material with water steam, or hydrogen embrittlement, and to reduce heat generation during cladding oxidation and increase “processing time” under accident conditions before re-flooding of the nuclear core.
  • 1.2K
  • 11 Oct 2022
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