Search

Introduction: Periodontal ligament cells (PDLC) respond to the application of mechanical forces by releasing various molecules that participate in bone remodeling. Whether these cellular reactions take place at the same rate in adolescent and adult patients is not known. In this study, we aimed to evaluate differences in genetic expression, if any, between the release of various inflammatory mediators from PDLC in adolescent and adult patients before and after the application of orthodontic forces.Methods: Forty subjects with bimaxillary dentoalveolar protrusion requiring extraction of first premolars for orthodontic treatment were selected and divided into 2 groups. Group A included 20 adolescents (aged 12-20 years), and group B included 20 adults (aged 35-50 years). Then, 35-50 g of force were applied to the maxillary first premolars, and teeth were extracted at different periods: pretreatment (control group), 7 days, 14 days, and 28 days (experimental group). The periodontal ligament was scraped from the middle third of the root, and the beta-galactosidase assay was performed in the control group. RNA extraction, DNase treatment, quantitative polymerase chain reaction, and complementary DNA synthesis were performed in the experimental group.Results: Adult PDLC exhibited senescent changes through increased beta-galactosidase activity. The increase in the inflammatory response and bone resorption in adult patients was evident by increased prostaglandin E2, IL1B, and acid phosphatase mRNA expression levels. Controlled bone formation response by adolescent PDLC was evident from increased ALP and BGLAP mRNA levels and a balanced receptor activator of nuclear factor kappa-Β ligand/OPG ratio.Conclusions: The study could identify the reasons behind the differential response of adolescent and adult PDLC to orthodontic mechanics. [ABSTRACT FROM AUTHOR]

A composite polymer electrolyte system based on PEMA/PVAc/LiClO4/EC with different wt% of nano filler TiO2 was prepared by solution casting technique.The structural investigations of the prepared polymer electrolyte membranes were carried out using X-ray diffraction and Fourier Transform infrared spectroscopictechniques. The electrical measurements were performed at various temperatures 303–363 K using ac impedance technique. The maximum room temperature ionic conductivity of 2.745 × 10 −3  S/cm was obtained for the polymer electrolyte membrane with 10 wt% TiO2. The temperature dependent ionic conductivity plot exhibited VTF behaviour. The porous nature of the membranes was verified from the SEM and AFM images. The thermal investigations performed on the samples by DSC technique displayed prominent endothermic peaks which revealed that the samples with the incorporation of filler had undergone a transition tothe amorphous phase at lower temperatures. The thermal stability of the film (F3) of maximum ionicconductivity was found to be 260 °C by means of TG/DTA analysis. The wide electrochemical stability window of –2.1 V to +2.1 V and the cyclability & reversibility of the maximum ion conducting sample at ambient temperature were confirmed by carrying out the electrochemical characterizations such as linear sweep voltammetry and cyclic voltammetry respectively. [ABSTRACT FROM AUTHOR]

Countries worldwide are seeking to decarbonize the planet by 2050 to mitigate climate change. Green hydrogen (H 2) from water electrolysis is vital to worldwide decarbonization. Consequently, electrolysis-based green H 2 production for large-scale renewable energy power plants and other industrial and transportation applications has grown in popularity. The main objective of this work was to provide a recent review and evaluation of water electrolysis for green H 2 production. In this review, the water electrolysis process, which involves the electrochemical water splitting and photoelectrochemical (PEC) water splitting and their techno-commercial prospects including H 2 production cost, along with recent developments in electrode and photoelectrode materials, and their environmental aspects for green H 2 production were summarized. The results showed that the Ni-based catalyst improved the electrocatalytic activity at a current density of 10 mA/cm2, while TiO 2 -based catalysts enhanced PEC water-splitting processes with superior solar to H 2 (STH) efficiency (3.7–16.9%). The levelized cost of H 2 (LCOH) for PEC and polymer exchange membrane (PEM) electrolysis is almost similar about 9 $/kgH 2 , and combining water electrolysis with wind and solar energy decreases the LCOH, which surpassed coal power generation by 40%. According to the results of a life cycle assessment (LCA), global warming potential (GWP) is the environmental effect category that causes the most concern and is the subject of the most research. The PEC-based water splitting process is the most environmentally friendly H 2 production method since it emits the lowest GWP per kg of produced H 2 (1.0 kg CO 2 /Kg H 2) in comparison to wind-based PEM water electrolysis (4.0 kg CO 2 /Kg H 2) and PV-solar-based PEM water electrolysis (1.5 kg CO 2 /Kg H 2). Interestingly, the case studies in various countries related to the green H 2 were also discussed. Finally, the future of green H 2 production and the challenges it faces in achieving cost-effective commercial applications were discussed. [Display omitted] • Green H 2 from water electrolysis (WE) is vital to worldwide decarbonization. • WE process and their techno-commercial prospects were discussed. • Recent developments in electrode and photoelectrode materials was summarized. • An environmental aspect for green H 2 production was summarized. • Case studies in various countries related to the green H 2 were also discussed. [ABSTRACT FROM AUTHOR]