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CFRP hybrid bonded–bolted (HBB) joints combine the advantages of traditional joining methods, namely adhesive bonding, and bolting, to achieve optimal connection performance, making them the most favored connection method. The structural parameters of CFRP HBB joints, including overlap length, bolt-hole spacing, and fit clearance relationships, have a complex impact on connection performance. To enhance the connectivity performance of joint structures, this paper develops a multiscale finite element analysis model to investigate the impact of structural parameters on the strength of CFRP HBB joint structures. Coupled with experimental validation, the study reveals how changes in structural parameters affect the unidirectional tensile failure force of the joints. Building on this, an analytical approach and inverse design methodology for the mechanical properties of CFRP HBB joints based on deep supervised learning algorithms are developed. Neural networks accurately and efficiently predict the performance of joints with unprecedented combinations of parameters, thus expediting the inverse design process. This research combines experimentation and multiscale finite element analysis to explore the unknown relationships between the mechanical properties of CFRP HBB joints and their structural parameters. Furthermore, leveraging DNN neural networks, a rapid calculation method for the mechanical properties of hybrid joints is proposed. The findings lay the groundwork for the broader application and more intricate design of composite materials and their connection structures. [ABSTRACT FROM AUTHOR]

Against the background of the impact of multiple uncertain events, such as COVID-19, the Russia–Ukraine conflict, and China–US trade frictions, it is of great strategic significance for enterprises to achieve their own sustainable development by improving ESG (environmental, social, and internal governance) performance. Using the data of Chinese A-share listed companies from 2011 to 2020, this paper empirically explores the effect of economic policy uncertainty (EPU) on corporate ESG performance. We obtain the following results: (1) EPU can promote firms to enhance ESG performance, and in each sub-item of ESG performance, EPU has the strongest promotion effect on corporations' environmental performance (E), followed by social responsibility performance (S), while EPU has a relatively weak promotion effect on internal governance performance (G). (2) The mechanism test results show that EPU will exacerbate the credit risk of enterprises and then promote the improvement of enterprises' ESG performance. (3) The grouping test results show that EPU has a stronger promotion effect on the ESG performance of state-owned enterprises, high-carbon industries, low regional marketization level, and enterprises with strong regional government intervention. Against the realistic background of the frequent adjustment of economic policies, the research results provide empirical evidence for guiding enterprises to strengthen the construction of ESG systems. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effects of subchronic exposure to chlorpyrifos on reproductive toxicology of male rats. Forty healthy male rats were divided into four groups: three exposure groups and a control group. Chlorpyrifos was administered orally to male rats at 0, 2.7, 5.4, and 12.8mg/kg for 90 days to evaluate the toxic alterations in testicular histology, testicular marker enzyme activities and related genes expression levels, sperm dynamics, and testosterone levels. The body weight and the testis weight of animals did not show any significant changes. Chlorpyrifos brought about marked reduction in testicular sperm counts, sperm motility, and significant growth of sperm malformation rate in exposed males. Histopathological examination of testes showed mild to severe degenerative changes in seminiferous tubules at various dose levels. The levels of testosterone (T) showed a decreasing tendency, and there was a statistical difference between the 5.4, 12.8 mg/kg groups, and the control group. The levels of follicle stimulating hormone (FSH) were significantly increased in 5.4 and 12.8 mg/kg groups, but there were no obvious effects on the levels of luteinizing hormone (LH) and estradiol (E2). A significant increase in the activities of LDH and LDH-x was observed in chlorpyrifos exposed rats in 5.4 and12.8 mg/kg groups, but the expression levels of related genes had no significant differences between chlorpyrifos exposure groups and the control group. These results suggest that chlorpyrifos has adverse effects on reproductive system of male rats. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1083-1088, 2014. [ABSTRACT FROM AUTHOR]

Mixed oxygen ion and electron-conducting materials are viable cathodes for solid oxide fuel cells due to their excellent oxygen transport kinetics and mixed electrical conductivity, which ensure highly efficient operation at low and medium temperatures. However, iron-based double perovskite oxides usually exhibit poor electrocatalytic activity due to low electron and oxygen ion conductivity. In this paper, Ca is doped in PrBaFe 2 O 5+δ A-site to improve the electrochemical performance of PrBaFe 2 O 5+δ . Results show that replacing Pr with Ca does not change the crystal structure, and the Ca doping effectively increases the adsorbed oxygen content and accelerates the migration and diffusion rate of O 2- to the electrolyte|cathode interface. The polarization resistance of the symmetric cell PC 0.15 BF|CGO|PC 0.15 BF is 0.033 Ω·cm 2 at 800 °C, which is about 56% lower than that of PBF, confirming the enhancement of the mixed conduction of oxygen ions and electrons. In addition, the anode-supported single cell has a peak power density of 512 mW·cm -2 at 800 °C.

SrFe 1- x Si x O 3-δ F y cathode materials ( x = 0.05, 0.1, 0.15; y = 0, 0.1, 0.5) were prepared via a solid-state method. X-ray diffraction results show that the synthesized F doping samples were perovskite structure. X-ray photoelectron spectroscopy findings show that F - anions were doped into SrFe 1- x Si x O 3-δ . Transmission electron microscopy and energy-dispersive spectroscopy were performed to analyze the microstructure and element distribution in the materials, respectively. Double-layer composite cathode symmetric cells were prepared through a screen printing method. Scanning electron microscopy images revealed that the double-layer composite cathode adhered well to the electrolyte. The doping with F - can increase the coefficient of thermal expansion of SrFe 1- x Si x O 3-δ . The electrochemical impedance spectroscopy results indicate that the oxygen transport capacity of the SrFe 0.95 Si 0.05 O 3-δ material can be improved by doping with F - , but such a method can decrease the oxygen transport capacity of SrFe 0.9 Si 0.1 O 3-δ . At 800 °C, the peak power density of the single cell supported by an anode and SrFe 0.9 Si 0.1 O 3-δ F 0.1 as the cathode reached 388.91 mW/cm 2 . Thus, the incorporation of F - into SrFe 1- x Si x O 3-δ cathode materials can improve their electrochemical performance and enable their application as cathode materials for solid-oxide fuel cells., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Recent discovery of reversible N 6 -methyladenosine (m 6 A) methylation on messenger RNA (mRNA) and mapping of m 6 A methylomes in mammals, plant and yeast revealed potential regulatory functions of this RNA modification. However, the role of the m 6 A methylomes in amphibious is still poorly understood. Here, we examined the m 6 A transcriptome-wide profile in testis tissues of Xenopus laevis (X. laevis) with and without treatment with 100 μg/L atrazine (AZ) through m 6 A sequencing analysis using the latest Illumina HiSeq sequencer. The results revealed that m 6 A is a highly conserved modification of mRNA in X. laevis. Distinct from that in mammals, m 6 A in X. laevisis enriched around the stop codon and start codon, as is reported in plant. We then investigated the differential expression m 6 A in testes of AZ-exposed X. laevis and compared that with the X. laevis in the control group by m 6 A sequencing. The results indicated that AZ leads to altered expression profile in 1380 m 6 A modification sites (696 upregulated and 684 downregulated). KEGG pathway analysis indicates that the "NOD-like receptors", "tight junction", "Peroxisome proliferator-activated receptors", "adherens junctions", "Glycerophospholipid metabolism" and "Fatty acid biosynthesis" signaling pathways may be associated with abnormal testis development of X. laevis due to exposure to AZ. Analysis results showed a positive correlation between m 6 A modification and mRNA abundance, suggesting a regulatory role of m 6 A in amphibious gene expression. Our first report of m 6 A transcriptome-wide map of an amphibian species X. laevis presented here provides a starting roadmap for uncovering m 6 A functions that may affect/control amphibian testis development., Competing Interests: Declaration of competing interest The authors declare they have no actual or potential competing financial interests., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Objective: To study the effects of zeranol on spermiogenesis function of mice and its possible mechanism., Methods: 40 healthy mature male mice were randomly divided into four groups: negative group and zeranol exposure groups (25, 50, 100 mg/kg). Male mice were respectively administered with zeranol at the doses of 25, 50, and 100 mg/kg for 35 days and killed. The weights of spermary, epididymis and spermatocyst were measured. The sperm counting, motility and the percent of abnormal sperms were observed. Pathological changes of testicle tissue were also observed., Results: In comparison with control group, the visceral coefficient of spermatocysts and sperm counting of zeranol exposure groups were all decreased ( P < 0.05). Sperm motility were significantly decreased in the median and high exposure groups (P < 0.05). Pathological alterations of testes were also observed. Seminiferous epithelium was reduced in exposure groups, loose and anomalistic organization. Sperm counts were also reduced in the lumina of seminiferous tubules with glair., Conclusion: Zeranol have toxicity effect on spermigenesis function of male mice.