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Background Oxidative stress and energy metabolism are important factors that affect sperm quality in male individuals. However, the majority of available studies are based on animal models, and evidence from human studies is still inadequate. Besides, most previous studies have paid more attention to the effects of oxidative stress and energy metabolism on sperm concentration and motility, with a little focus on their impact on sperm motility velocity and trajectory and other specific objective indicators evaluating the state of male infertility. Objective To investigate the effects of biological indicators related to oxidative stress and energy metabolism on sperm concentration, motility, movement velocity and trajectory in male adults, thus to provide epidemiological evidence for precise intervention of male reproductive health problems. Methods One hundred and nine volunteers were recruited as subjects from the Center of Reproductive Medicine in Xijing Hospital, Air Force Medical University from June to December 2021. Their semen samples were collected. The computer-assisted sperm analysis system was applied to detect sperm concentration parameters (sperm concentration, linear motion sperm concentration), sperm motility〔total sperm motility, progressive motility (PR), non-progressive motility (NP) 〕, sperm motility velocity parameters〔curvilinear velocity (VCL), straight-line velocity (VSL), average path velocity (VAP) 〕 and sperm motility trajectory parameters 〔mean amplitude of lateral head displacement (ALH), mean beat-cross frequency (BCF), mean angular displacement (MAD), linearity coefficient (LIN), wobble coefficient (WOB), straightness coefficient (STR) 〕. Besides that, the levels of malondialdehyde (MDA) and reduced glutathione (GSH) in semen samples were measured as oxidative stress markers, and the level of sperm adenosine triphosphate (ATP) was measured to assess the level of energy metabolism. General linear model (GLM) was used to evaluate the correlation of MDA and GSH and ATP with sperm quality parameters. Results A total of 67 sperm samples were used to examine oxidative stress level, and 42 sperm samples were employed to assess the level of energy metabolism. The analysis using the GLM demonstrated that in terms of oxidative stress level, MDA level was negatively correlated with linear motion sperm concentration, total sperm motility, PR, NP, VCL, VSL, VAP, ALH, BCF, MAD, LIN, WOB, and STR (P

Selective producing ethanol from CO2 electroreduction is highly demanded, yet the competing ethylene generation route is commonly more thermodynamically preferred. Herein, we reported an efficient CO2‐to‐ethanol conversion (53.5 % faradaic efficiency at −0.75 V versus reversible hydrogen electrode (vs. RHE)) over an oxide‐derived nanocubic catalyst featured with abundant "embossment‐like" structured grain‐boundaries. The catalyst also attains a 23.2 % energy efficiency to ethanol within a flow cell reactor. In situ spectroscopy and electrochemical analysis identified that these dualphase Cu(I) and Cu(0) sites stabilized by grain‐boundaries are very robust over the operating potential window, which maintains a high concentration of co‐adsorbed *CO and hydroxyl (*OH) species. Theoretical calculations revealed that the presence of *OHad not only promote the easier dimerization of *CO to form *OCCO (ΔG~0.20 eV) at low overpotentials but also preferentially favor the key *CHCOH intermediate hydrogenation to *CHCHOH (ethanol pathway) while suppressing its dehydration to *CCH (ethylene pathway), which is believed to determine the remarkable ethanol selectivity. Such imperative intermediates associated with the bifurcation pathway were directly distinguished by isotope labelling in situ infrared spectroscopy. Our work promotes the understanding of bifurcating mechanism of CO2ER‐to‐hydrocarbons more deeply, providing a feasible strategy for the design of efficient ethanol‐targeted catalysts. [ABSTRACT FROM AUTHOR]

Seventeen typical coal mine accidents were analyzed with their cause statistics by use of encoding tree method. The analysis results show that organizational management failure of coal mine is the mainly cause of coal mine accidents with the most serious influence. The organizational management failure of coal mine was classified, and some improvement measures about the organizational management failure were proposed including playing an exemplary role of leaders, improving organizational communication and enhancing safety study.

Electrochemical CO2 reduction reaction (CO2RR) provides a promising approach for sustainable chemical fuel production of carbon neutrality. Neutral and alkaline electrolytes are predominantly employed in the current electrolysis system, but with striking drawbacks of (bi)carbonate (CO32−/HCO3−) formation and crossover due to the rapid and thermodynamically favourable reaction between hydroxide (OH−) with CO2, resulting in low carbon utilization efficiency and short‐lived catalysis. Very recently, CO2RR in acidic media can effectively address the (bi)carbonate issue; however, the competing hydrogen evolution reaction (HER) is more kinetically favourable in acidic electrolytes, which dramatically reduces CO2 conversion efficiency. Thus, it is a big challenge to effectively suppress HER and accelerate acidic CO2RR. In this review, we begin by summarizing the recent progress of acidic CO2 electrolysis, discussing the key factors limiting the application of acidic electrolytes. We then systematically discuss addressing strategies for acidic CO2 electrolysis, including electrolyte microenvironment modulation, alkali cations adjusting, surface/interface functionalization, nanoconfinement structural design, and novel electrolyzer exploitation. Finally, the new challenges and perspectives of acidic CO2 electrolysis are suggested. We believe this timely review can arouse researchers′ attention to CO2 crossover, inspire new insights to solve the "alkalinity problem" and enable CO2RR as a more sustainable technology. [ABSTRACT FROM AUTHOR]

Background: Immune checkpoint blockade (ICB) therapy can be effective against clear cell renal cell carcinoma (ccRCC), but many patients show no benefit. Tumor-derived pericytes (TDPs) may promote tumor progression by influencing T cells and are an immunotherapy target; however, they may comprise functionally distinct subtypes. We aimed to identify markers of tumor-promoting TDPs and develop TDP-targeting strategies to enhance ICB therapy effectiveness against ccRCC. Methods: We analyzed the relationship between endosialin (EN) expression and cytotoxic T-lymphocyte (CTL) infiltration in ccRCC tumor samples using flow cytometry and in a ccRCC-bearing mice inhibited for EN via knockout or antibody-mediated blockade. The function of ENhigh TDPs in CTL infiltration and tumor progression was analyzed using RNA-sequencing (RNA-seq) data from ccRCC tissue-derived TDPs and single-cell RNA-seq (scRNA-seq) data from an online database. The role of EN in TDP proliferation and migration and in CTL infiltration was examined in vitro. Finally, we examined the anti-tumor effect of combined anti-EN and anti-programmed death 1 (PD-1) antibodies in ccRCC-bearing mice. Results: High EN expression was associated with low CTL infiltration in ccRCC tissues, and inhibition of EN significantly increased CTL infiltration in ccRCC-bearing mice. RNA-seq and scRNA-seq analyses indicated that high EN expression represented the TDP activation state. EN promoted TDP proliferation and migration and impeded CTL infiltration in vitro. Finally, combined treatment with anti-EN and anti-PD-1 antibodies synergistically enhanced anti-tumor efficacy. Conclusion: ENhigh TDPs are in an activated state and inhibit CTL infiltration into ccRCC tissues. Combined treatment with anti-EN and anti-PD-1 antibodies may improve ICB therapy effectiveness against ccRCC. [ABSTRACT FROM AUTHOR]

For problems that current coal mine personnel positioning system adopts region positioning method, and cannot directly determine exact location and movement direction of underground personnel, an algorithm based on tree structure was proposed, which uses topological relations to calculate track that underground personnel may walk. The algorithm defines a topology model with point and segment, segment and segment as well as segment and point. Based on the model, tree structure is built and personnel walking track is got by its hierarchy traversal. In the calculation process, the algorithm uses real-time status information of receiver to preclude impact of non-working receiver and substations automatically, and ensures tracking accuracy.

In order to solve problems of disorderly wiring and inconvenient install and maintenance of sensors caused by single-parameter measurement of exsiting sensors used in safety monitoring and control system of coal(mine,) a design scheme of(mine-used multi-parameter) sensor was(proposed.) The(multi-)parameter sensor is designed by use of MSP430F149 single-chip microcomputer.It can transmit collected signals of gas concentration,CO concentration,O_2 concentration and temperature to LED for displaying after data processing and output alarming signal.Some testing results showed that the multi-parameter sensor has high precision,good stability,and strong anti-interference ability.

Metal halide perovskites, primarily used as optoelectronic devices, have not been applied for electrochemical conversion due to their insufficient stability in moisture. Herein, two bismuth‐based perovskites are introduced as novel electrocatalysts to convert CO2 into HCOOH in aqueous acidic media (pH 2.5), exhibiting a high Faradaic efficiency for HCOOH of >80 % in a wide potential range from −0.75 to −1.25 V. Their structural evolution against water was dynamically monitored by in situ spectra. Theoretical calculations further reveal that the formation of intermediate OCHO* on bismuth sites of Cs3Bi2Br9(111) play a pivotal role toward HCOOH production, which has a lower energy barrier than that on Cs2AgBiBr6(001) surfaces. Significantly, CO2 reacts with protons instead of water which can enhance CO2 reduction rate and suppress hydrogen evolution by avoiding carbonate formation in acidic electrolytes. This work paves the way for the extensive investigation of halide perovskites in aqueous systems. [ABSTRACT FROM AUTHOR]

The reuse of construction and demolition waste has become vitally important because of the requirements of environmental protection and sustainable development. The vibration mixing process is a new technology and novel method that improves the performance of concrete by optimizing the mixing process without changing constituents. This study discusses the 100% recycled and multi-recycled coarse aggregates concrete using the vibration mixing process and investigates the fresh and hardened properties. The results show that the recycled and multi-recycled concrete using the vibration mixing process experienced obviously higher compressive strength than that of non-vibration mixing process. At 120 days, the compressive strength of all mixtures surpassed the target strength (40 MPa), except for the multi-recycled concrete with the non-vibration mixing process. More importantly, the compressive strength of the recycled and multi-recycled concrete using vibration mixing was larger than the previous-generation concrete using non-vibration mixing. Another interesting finding was that the coefficient of variation of compressive strength using vibration mixing was smaller and the concrete quality was better and more stable. The splitting tensile strength of recycled and multi-recycled concrete was also investigated and discussed. In addition, the results of t-tests show that vibration mixing has a significant influence on the compressive and splitting tensile strength of recycled and multi-recycled concrete. It is expected that the vibration mixing process could be a more efficient way to help the wide application of recycled and multi-recycled concrete. [ABSTRACT FROM AUTHOR]