The association between XPC Lys939Gln gene polymorphism and urinary bladder cancer susceptibility: a systematic review and meta-analysis

BACKGROUND: Numerous epidemiological studies have been conducted to explore the association between the Lys939Gln polymorphism of Xeroderma pigmentosum group C (XPC) gene and urinary bladder cancer susceptibility. However, the results remain inconclusive. In order to derive a more precise estimation of this relationship, a large and update meta-analysis was performed in this study. METHODS: A comprehensive search was conducted through researching MEDLINE, EMBASE, PubMed, Web of Science, China Biomedical Literature database (CBM) and China National Knowledge Infrastructure (CNKI) databases before June 2013. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate the strength of the association. RESULTS: A total of 12 studies with 4828 cases and 4890 controls for evaluating the XPC Lys939Gln polymorphism and urinary bladder cancer were included. Overall, there was significant associations between the XPC Lys939Gln polymorphism and urinary bladder cancer risk were found for homozygous model (OR = 1.352, 95% CL = 1.088-1.681), heterozygous model (OR = 1.354, 95% CL = 1.085-1.688), and allele comparison (OR = 1.109, 95% CL = 1.013-1.214). In subgroup analysis by ethnicity and source of controls, there were still significant associations detected in some genetic models. CONCLUSION: Our meta-analysis suggested that the XPC Lys939Gln polymorphism contributed to the risk of urinary bladder cancer. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here:

Nano-structured SnO2-carbon composites obtained by in situ spray pyrolysis method as anodes in lithium batteries

In this paper, we report on a series of SnO2-carbon nano-composites synthesized by in situ spray pyrolysis of a solution of SnCl2·2H2O and sucrose at 700 °C. The process results in super fine nanocrystalline SnO2, which is homogeneously distributed inside the amorphous carbon matrix. The SnO2 was revealed as a structure of broken hollow spheres with porosity on both the inside and outside particle surfaces. This structure promises a highly developed specific surface area. X-ray diffraction (XRD) patterns and transmission electron microscope (TEM) images revealed the SnO2 crystal size is about 5–15 nm. These composites show a reversible lithium storage capacity of about 590 mAh g−1 in the first cycle. The discharge curve of the composite indicates that lithium is stored in crystalline tin, but not in amorphous carbon. However, the conductive carbon matrix with high surface area provides a buffer layer to cushion the large volume change in the tin regions, which contributes to the reduced capacity fade compared to nonacrystalline SnO2 without carbon

A Comprehensive Review on Controlling Surface Composition of Pt-Based Bimetallic Electrocatalysts

With increasing energy demands worldwide, significant efforts have been made to develop superior electrocatalysts for efficient energy conversion systems. Among all the electrocatalysts exploited, Pt-based bimetallic nanomaterials stand out by virtue of their high catalytic activity and relatively low cost due to the introduction of a nonprecious metal component. It should be noted that electrocatalytic reactions only take place on the surface of catalysts, so investigations of the surface composition of Pt-based bimetallic nanomaterials are necessary for practical electrocatalysts. In this review, recent studies on controlling the surface composition of Pt-based bimetallic catalysts for the oxygen reduction reaction, formic acid electrooxidation, and ethanol electrooxidation are summarized. The controlling strategies, including the chemical method and the electrochemical method, are discussed. The impacts of surface composition compositions on the electrocatalytic performance are also discussed. Finally, the challenges and future directions for controlling the surface composition of Pt-based bimetallic nanomaterials are addressed

CoSe2/MoSe2Heterostructures with Enriched Water Adsorption/Dissociation Sites towards Enhanced Alkaline Hydrogen Evolution Reaction

Transition-metal dichalcogenides (TMDs) are promising electrocatalysts toward the hydrogen evolution reaction (HER) in acid media, but they show significantly inferior activity in alkaline media due to the extremely sluggish water dissociation kinetics. Herein, CoSe2/MoSe2heterostructures with CoSe2quantum dots anchored on MoSe2nanosheets are synthesized towards enhanced alkaline HER catalytic activity. The incorporation of CoSe2is intended to construct additional water adsorption sites on the basal planes of MoSe2to promote water dissociation. The CoSe2/MoSe2heterostructures show substantially enhanced activity over MoSe2and CoSe2in 1 m KOH. The optimal overpotential required to reach a current density of 10 mA cm−2is merely 218 mV, which is more than 100 mV greater than that of MoSe2, which is by far the best performance demonstrated for precious-metal-free catalysts. Detailed analyses based on electrochemical testing demonstrate that the water adsorption and subsequent dissociation process is accelerated by CoSe2species with rich edge sites; meanwhile, MoSe2species provide sufficient active sites for the adsorption and combination of adsorbed hydrogen (H.). These results provide an effective strategy for developing earth-abundant catalysts with high activity for the alkaline HER, and are of great significance to promote the practical application of alkaline water electrolysis

Alkali-Metal Sulfide as Cathodes toward Safe and High-Capacity Metal (M = Li, Na, K) Sulfur Batteries

© 2020 Wiley-VCH GmbH Rechargeable alkali-metal–sulfur (M–S) batteries, because of their high energy density and low cost, have been recognized as one of the most promising next-generation energy storage technologies. Nevertheless, the dissolution of metal polysulfides in organic liquid electrolytes and safety issues related to the metal anodes are greatly hindering the development of the M–S batteries. Alkali-metal sulfides (M2Sx) are emerging as cathode materials, which can pair with various safe nonalkali-metal anodes, such as silicon and tin. As a result, the combined M2Sx cathode-based M–S batteries can achieve high capacity as well as safety, thereby providing a more feasible battery technology for practical applications. In this review, recent progress in developing M2Sx cathode-based M–S batteries is systematically summarized, including the activation methods for M2Sx cathodes, M2Sx cathode optimization, and the improvement of electrolytes and anode materials. Furthermore, perspectives and future research directions of M2Sx cathode-based M–S batteries are proposed

Exo84c-regulated degradation is involved in the normal self-incompatible response in Brassicaceae

The self-incompatibility system evolves in angiosperms to promote cross-pollination by rejecting self-pollination. Here, we show the involvement of Exo84c in the SI response of both Brassica napus and Arabidopsis. The expression of Exo84c is specifically elevated in stigma during the SI response. Knocking out Exo84c in B.napus and SI Arabidopsis partially breaks down the SI response. The SI response inhibits both the protein secretion in papillae and the recruitment of the exocyst complex to the pollen-pistil contact sites. Interestingly, these processes can be partially restored in exo84c SI Arabidopsis. After incompatible pollination, the turnover of the exocyst-labeled compartment is enhanced in papillae. However, this process is perturbed in exo84c SI Arabidopsis. Taken together, our results suggest that Exo84c regulates the exocyst complex vacuolar degradation during the SI response. This process is likely independent of the known SI pathway in Brassicaceae to secure the SI response. [Abstract copyright: Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.

Imprint of the stochastic nature of photon emission by electrons on the proton energy spectra in the laser-plasma interaction

The impact of stochasticity effects (SEs) in photon emissions on the proton energy spectra during laser-plasma interaction is theoretically investigated in the quantum radiation-dominated regime, which may facilitate SEs experimental observation. We calculate the photon emissions quantum mechanically and the plasma dynamics semiclassically via two-dimensional particle-in-cell simulations. An ultrarelativistic plasma generated and driven by an ultraintense laser pulse head-on collides with another strong laser pulse, which decelerates the electrons due to radiation-reaction effect and results in a significant compression of the proton energy spectra because of the charge separation force. In the considered regime the SEs are demonstrated in the shift of the mean energy of the protons up to hundreds of MeV. This effect is robust with respect to the laser and target parameters and measurable in soon available strong laser facilities