Active Passivation of Anion Vacancies in Antimony Selenide Film for Efficient Solar Cells.

Binary antimony selenide (Sb2Se3) is a promising inorganic light-harvesting material with high stability, nontoxicity, and wide light harvesting capability. In this photovoltaic material, it has been recognized that deep energy level defects with large carrier capture cross section, such as VSe (selenium vacancy), lead to serious open-circuit voltage (VOC) deficit and in turn limit the achievable power conversion efficiency (PCE) of Sb2Se3 solar cells. Understanding the nature of deep-level defects and establishing effective method to eliminate the defects are vital to improving VOC. In this study, a novel directed defect passivation strategy is proposed to suppress the formation of VSe and maintain the composition and morphology of Sb2Se3 film. In particular, through systematic study on the evolution of defect properties, the pathway of defect passivation reaction is revealed. Owing to the inhibition of defect-assisted recombination, the VOC increases, resulting in an improvement of PCE from 7.69% to 8.90%, which is the highest efficiency of Sb2Se3 solar cells prepared by thermal evaporation method with superstrate device configuration. This study proposes a new understanding of the nature of deep-level defects and enlightens the fabrication of high quality Sb2Se3 thin film for solar cell applications.

Injectable, Electroconductive, Free Radical Scavenging Silk Fibroin/Black Phosphorus/Glycyrrhizic Acid Nanocomposite Hydrogel for Enhancing Spinal Cord Repair.

Spinal cord injury (SCI) often leads to a severe permanent disability. A poor inflammatory microenvironment and nerve electric signal conduction block are the main reasons for difficulty in spinal cord nerve regeneration. In this study, black phosphorus (BP) and glycyrrhizic acid (GA) are integrated into methacrylate-modified silk fibroin (SF) to construct a bifunctional injectable hydrogel (SF/BP/GA) with appropriate conductivity and the ability to inhibit inflammation to promote neuronal regeneration after SCI. This work discovers that the SF/BP/GA hydrogel can reduce the oxidative damage mediated by oxygen free radicals, promote the polarization of macrophages toward the anti-inflammatory M2 phenotype, reduce the expression of inflammatory factors, and improve the inflammatory microenvironment. Moreover, it induces neural stem cell (NSC) differentiation and neurosphere formation, restores signal conduction at the SCI site in vivo, and ameliorates motor function in mice with spinal cord hemisection, revealing a significant neural repair effect. An injectable, electroconductive, free-radical-scavenging hydrogel is a promising therapeutic strategy for SCI repair.

Advances of Zn Metal-Free "Rocking-Chair"-Type Zinc Ion Batteries: Recent Developments and Future Perspectives.

Aqueous zinc ion battery (AZIBs) has attracted the attention of many researchers because of its safety, economy, environmental protection, and high ionic conductivity of electrolytes. However, the battery greatly suffers from zinc dendrite produced by zinc metal anode leading to poor cycle life and even unsafe problems, which limit its further development for various important applications. It is known that the success of the commercialization of lithium-ion batteries (LIBs) is mainly due to replacement of lithium metal anode with graphite, which avoids the formation of Li dendrite. Therefore, it is an important step to develop aqueous zinc ion anode to replace conventional zinc metal one with zinc-metal free anode material. In this review, the working principle and development prospect of "rocking-chair" AZIBs are introduced. The research progress of different types of zinc metal-free anode materials and cathode materials in "rocking-chair" AZIBs is reviewed. Finally, the limitations and challenges of the Zn metal-free "rocking-chair" AZIBs as well as solutions are deeply discussed, aiming to provide new strategies for the development of advanced zinc-ion batteries.

Association of lifestyle habits and cardiovascular risk among sedentary adults.

This study aimed to analyze the association of lifestyle habits (physical activity, sleep habits, and eating habits) with cardiovascular risk (arterial stiffness and autonomic nervous system function) among sedentary adults. Sixty adults of sedentariness and physical activity were evaluated by accelerometers; sleep and eating habits were assessed by questionnaires; cardiovascular risks were assessed by pulse wave velocity (PWV), ankle-brachial index, flow mediated dilation, and heart rate variability; circulating biomarkers were also determined. Prolonged sitting (represented by longer maximum length of sedentary bouts, lower length of sedentary breaks, and more total time of sitting) were (P < .05) significantly associated with matrix metalloproteinases, neuropeptide Y, C-reactive protein, peptide Y, ghrelin, and leptin; significant associations (P < .05) were also observed of total time in physical activity with most circulating biomarkers except interleukin-6, tumor necrosis factor-α, and adiponectin. Sleep habits, especially sleep efficiency, were (P < .05) significantly associated with PWV, ankle-brachial index, and circulating biomarkers. Eating habits (including emotional overeating and enjoyment of food) were (P < .05) significantly associated with PWVs and flow mediated dilation; satiety responsiveness and enjoyment of food were (P < .05) significantly associated with low-frequency spectral component expressed in normalized units, high frequency spectral component expressed in normalized units, and ratio between low-frequency/high frequency spectral component expressed in normalized units. The findings indicated that several lifestyle habits among sedentary adults were closely associated with increased cardiovascular risk. Sedentary people were encouraged to live with sufficient physical activity, good sleep, and healthy eating habits for decreasing arterial stiffness and balancing autonomic nervous function.

Synthesis and bioevaluation of novel stilbene-based derivatives as tubulin/HDAC dual-target inhibitors with potent antitumor activities in vitro and in vivo.

A series of novel stilbene-based derivatives were designed and synthesized as tubulin/HDAC dual-target inhibitors. Among forty-three target compounds, compound II-19k not only exhibited considerable antiproliferative activity in the hematological cell line K562 with IC50 value of 0.003 µM, but also effectively inhibited the growth of various solid tumor cell lines with IC50 values ranging from 0.005 to 0.036 µM. The mechanism studies demonstrated that II-19k could inhibit microtubules and HDACs at the cellular level, block cell cycle arrest at G2 phase, induce cell apoptosis, and reduce solid tumor cells metastasis. What's more, the vascular disrupting effects of compound II-19k were more pronounced than the combined administration of parent compound 8 and HDAC inhibitor SAHA. The in vivo antitumor assay of II-19k also showed the superiority of dual-target inhibition of tubulin and HDAC. II-19k significantly suppressed the tumor volume and effectively reduced tumor weight by 73.12% without apparent toxicity. Overall, the promising bioactivities of II-19k make it valuable for further development as an antitumor agent.

Aerobic exercises regulate the epididymal anion homeostasis of high-fat diet-induced obese rats through TRPA1-mediated Cl- and HCO3- secretion†.

Aerobic exercises could improve the sperm motility of obese individuals. However, the underlying mechanism has not been fully elucidated, especially the possible involvement of the epididymis in which sperm acquire their fertilizing capacity. This study aims to investigate the benefit effect of aerobic exercises on the epididymal luminal milieu of obese rats. Sprague-Dawley male rats were fed on a normal or high-fat diet (HFD) for 10 weeks and then subjected to aerobic exercises for 12 weeks. We verified that TRPA1 was located in the epididymal epithelium. Notably, aerobic exercises reversed the downregulated TRPA1 in the epididymis of HFD-induced obese rats, thus improving sperm fertilizing capacity and Cl- concentration in epididymal milieu. Ussing chamber experiments showed that cinnamaldehyd (CIN), agonist of TRPA1, stimulated an increase of the short-circuit current (ISC) in rat cauda epididymal epithelium, which was subsequently abolished by removing the ambient Cl- and HCO3-. In vivo data revealed that aerobic exercises increased the CIN-stimulated Cl- secretion rate of epididymal epithelium in obese rats. Pharmacological experiments revealed that blocking cystic fibrosis transmembrane regulator (CFTR) and Ca2+-activated Cl- channel (CaCC) suppressed the CIN-stimulated anion secretion. Moreover, CIN application in rat cauda epididymal epithelial cells elevated intracellular Ca2+ level, and thus activate CACC. Interfering with the PGHS2-PGE2-EP2/EP4-cAMP pathway suppressed CFTR-mediated anion secretion. This study demonstrates that TRPA1 activation can stimulate anion secretion via CFTR and CaCC, which potentially forming an appropriate microenvironment essential for sperm maturation, and aerobic exercises can reverse the downregulation of TRPA1 in the epididymal epithelium of obese rats.

V2O3@C Microspheres as the High-Performance Cathode Materials for Advanced Aqueous Zinc-Ion Storage.

Vanadium oxides attract increasing research interests for constructing the cathode of aqueous zinc-ion batteries (ZIBs) because of high theoretical capacity, but the low intrinsic conductivity and unstable phase changes during the charge/discharge process pose great challenges for their adoption. In this work, V2O3@C microspheres were developed to achieve enhanced conductivity and improved stability of phase changes. Compounding vanadium oxides and conductive carbon through the in-situ carbonization led to significant improvement of the cathode materials. ZIBs prepared with V2O3@C cathodes produce a specific capacity of 420 mA h g-1 at 0.2 A g-1. A reversible capacity of 132 mA h g-1 was achieved at 21.0 A g-1. After 2000 cycles, the electrode could still deliver a capacity of 202 mA h g-1 at the current of 5.0 A g-1. Besides, the energy density of batteries constructed with the thus-prepared electrodes was about 294 W h kg-1 at 148 W kg-1 power. The in-situ compounding of V2O3 and carbon resulted in a microstructure that facilitated the stable phase transformation of ZnxV2O5-a·nH2O (ZnVOH), which provided more Zn2+ storage activity than the original phase before electrochemical activation. Moreover, the in-situ compositing strategy presents a simple route to the development of ZIB cathodes with promising performance.

Mechanistic Study of the Transition from Antimony Oxide to Antimony Sulfide in the Hydrothermal Process to Obtain Highly Efficient Solar Cells.

Obtaining high-quality absorber layers is a major task for constructing efficient thin-film solar cells. Hydrothermal deposition is considered a promising method for preparing high-quality antimony sulfide (Sb2 S3 ) films for solar cell applications. In the hydrothermal process, the precursor reactants play an important role in controlling the film formation process and thus the film quality. In this study, Sb2 O3 is applied as a new Sb source to replace the traditional antimony potassium tartrate to modulate the growth process of the Sb2 S3 film. The reaction mechanism of the transition from Sb2 O3 to Sb2 S3 in the hydrothermal process is revealed. Through controlling the nucleation and deposition processes, high-quality Sb2 S3 films are prepared with longer carrier lifetimes and lower deep-level defect densities than those prepared from the traditional Sb source of antimony potassium tartrate. Consequently, a solar cell device based on this improved Sb2 S3 delivers a high power conversion efficiency of 6.51 %, which is in the top tier for Sb2 S3 -based solar devices using hydrothermal methods. This research provides a new and competitive Sb source for hydrothermal growth of high-quality antimony chalcogenide films for solar cell applications.

Berry-Curvature Engineering for Nonreciprocal Directional Dichroism in Two-Dimensional Antiferromagnets.

In two-dimensional antiferromagnets, we find that the mixed Berry curvature can be attributed as the geometrical origin of the nonreciprocal directional dichroism (NDD), which refers to the difference in light absorption between opposite propagation directions. This Berry curvature is closely related to the uniaxial strain in accordance with the symmetry constraint, leading to a highly tunable NDD, whose sign and strength can be tuned via strain direction. We choose the lattice model of MnBi_{2}Te_{4} as a concrete example. The coupling between mixed Berry curvature and strain also suggests the magnetic quadrupole of the Bloch wave packet as the macroscopic order parameter probed by the NDD in two dimensions, which is distinct from the multiferroic order P×M or the spin toroidal and quadrupole order within a unit cell in previous studies. Our work paves the way for the Berry-curvature engineering for optical nonreciprocity in two-dimensional antiferromagnets.

Genomic footprints related with adaptation and fumonisins production in Fusarium proliferatum.

Fusarium proliferatum is the principal etiological agent of rice spikelet rot disease (RSRD) in China, causing yield losses and fumonisins contamination in rice. The intraspecific variability and evolution pattern of the pathogen is poorly understood. Here, we performed whole-genome resequencing of 67 F. proliferatum strains collected from major rice-growing regions in China. Population structure indicated that eastern population of F. proliferatum located in Yangtze River with the high genetic diversity and recombinant mode that was predicted as the putative center of origin. Southern population and northeast population were likely been introduced into local populations through gene flow, and genetic differentiation between them might be shaped by rice-driven domestication. A total of 121 distinct genomic loci implicated 85 candidate genes were suggestively associated with variation of fumonisin B1 (FB1) production by genome-wide association study (GWAS). We subsequently tested the function of five candidate genes (gabap, chsD, palA, hxk1, and isw2) mapped in our association study by FB1 quantification of deletion strains, and mutants showed the impact on FB1 production as compared to the wide-type strain. Together, this is the first study to provide insights into the evolution and adaptation in natural populations of F. proliferatum on rice, as well as the complex genetic architecture for fumonisins biosynthesis.

Genome-Wide Characterization Reveals Variation Potentially Involved in Pathogenicity and Mycotoxins Biosynthesis of Fusarium proliferatum Causing Spikelet Rot Disease in Rice.

Fusarium proliferatum is the primary cause of spikelet rot disease in rice (Oryza sativa L.) in China. The pathogen not only infects a wide range of cereals, causing severe yield losses but also contaminates grains by producing various mycotoxins that are hazardous to humans and animals. Here, we firstly reported the whole-genome sequence of F. proliferatum strain Fp9 isolated from the rice spikelet. The genome was approximately 43.9 Mb with an average GC content of 48.28%, and it was assembled into 12 scaffolds with an N50 length of 4,402,342 bp. There is a close phylogenetic relationship between F. proliferatum and Fusarium fujikuroi, the causal agent of the bakanae disease of rice. The expansion of genes encoding cell wall-degrading enzymes and major facilitator superfamily (MFS) transporters was observed in F. proliferatum relative to other fungi with different nutritional lifestyles. Species-specific genes responsible for mycotoxins biosynthesis were identified among F. proliferatum and other Fusarium species. The expanded and unique genes were supposed to promote F. proliferatum adaptation and the rapid response to the host's infection. The high-quality genome of F. proliferatum strain Fp9 provides a valuable resource for deciphering the mechanisms of pathogenicity and secondary metabolism, and therefore shed light on development of the disease management strategies and detoxification of mycotoxins contamination for spikelet rot disease in rice.

Zn0.52 V2 O5-a ⋠1.8 H2 O Cathode Stabilized by In Situ Phase Transformation for Aqueous Zinc-Ion Batteries with Ultra-Long Cyclability.

Developing cathode materials integrating good rate performance and sufficient cycle life is the key to commercialization of aqueous zinc-ion batteries. The hyperstable Zn0.52 V2 O5-a ⋅1.8 H2 O (ZVOH) cathode with excellent rate performance has been successfully developed via an in situ self-transformation from zinc-rich Zn3 V3 O8 (ZVO) in this study. Different from the common synthetic method of additional Zn2+ pre-insertion, ZVOH is obtained from the insertion of structural H2 O and the removal of excess Zn2+ in ZVO, ensuring the lattice structure of ZVOH remains relatively intact during the phase transition and rendering good structural stabilities. The ZVOH delivers a reversible capacity of 286.2 mAh g-1 at 0.2 A g-1 and of 161.5 mAh g-1 at 20 A g-1 over 18 000 cycles with a retention of 95.4 %, demonstrating excellent rate performance and cyclic stability. We also provide new insights on the structural self-optimization of Znx (CF3 SO3 )y (OH)2x-y ⋅n H2 O byproducts and the effect on the mobility of Zn2+ by theoretical calculations and experimental evidence.

Quantitative Detection of Components in Polymer-Bonded Explosives through Near-Infrared Spectroscopy with Partial Least Square Regression.

The components in polymer-bonded explosive X, including cyclotetramethylene-tetranitramine, paraffin, and polytetrafluoroethylene, were determined using near-infrared (NIR) spectroscopy. Using partial least squares as the multivariate calibration method, quantitative calibration models for components in X were verified internally and externally. The possible combinations of eight general spectral pretreatment methods and different bands of the scanning spectral region (12,500-4000 cm-1) were established. The models were analyzed, evaluated, and optimized via the fitting effect. The data were combined with the mathematical meaning of the model spectral pretreatment methods and the chemical significance of the modeling spectral bands. Prediction performance offered optimal quantitative calibration models. Paired bilateral Student's t tests show that there is no significant difference between the values obtained by NIR and chemical analysis methods, and the NIR method has good accuracy. Moreover, the precision of the NIR method is better than that of the chemical method, and the analysis time is reduced from 2 days to a few minutes.

Effective Trapping of Polysulfides Using Functionalized Thin-Walled Porous Carbon Nanotubes as Sulfur Hosts for Lithium-Sulfur Batteries.

Owing to their high aspect ratios and structures of high-mechanical-strength conductive scaffolds, carbon nanotubes (CNTs) are considered to be one of the most promising hosts for sulfur in lithium-sulfur batteries (LSBs). However, traditional CNTs with impermeable walls are not conducive to the penetration of sulfur, resulting in a large number of sulfur exposures to the electrolyte. Therefore, it is difficult to effectively limit the shuttle effect of polysulfides. Here, a kind of thin-walled porous amorphous carbon nanotube (HCNT) is adopted as the host for sulfur in LSBs. To further alleviate the shuttle effect, oxygen-containing functional groups (OCFGs) are introduced to modify HCNTs to form HOCNTs. The S/HOCNT composite with the embedded structure is successfully constructed. The S/HOCNT cathode demonstrates glorious cycling and rate performance (798.5 mAh g-1 at 0.2 C after 100 cycles and 511.6 mAh g-1 at 1 C after 500 cycles). The excellent electrochemical performance of S/HOCNT can be attributed to the embedded structure of sulfur in HOCNTs, which avoids direct contact with the electrolytes and strong bonding action of OCFGs and polysulfides, effectively limiting the shuttle effect of polysulfides.

Physical Forces Inducing Thin Amorphous Carbon Nanotubes Derived from Polymer Nanotube/SiO2 Hybrids with Superior Rate Capability for Lithium-Ion Batteries.

Different from the traditional template method, a thin amorphous carbon nanotube was prepared by constructing a polymer/SiO2 composite, utilizing the shrinking action of sulfonated polymer nanotubes (SPNTs) and the physical squeezing action of SiO2 on it during the pyrolysis of SPNT/SiO2. Remarkably, the heat treatment atmosphere (N2, N2-H2, or O2) has an important effect on the surface properties, pore structure, crystallinity, and especially the defect sites, leading to different lithium storage performances. Particularly, the sample calcined in N2-H2 (NHCNTs) exhibits outstanding reversible capacity (400.6 mA h g-1 at 2 A g-1 after 200 cycles) and rate capability (268.4 mA h g-1 at 5 A g-1 and 212.1 mA h g-1 at 10 A g-1 after 400 cycles), which are attributed to the thin-walled tubular structure and abundant defect sites. NOCNTs can be obtained by the thermal treatment of NCNTs (the sample of polymer pyrolysis in N2) in air, and the oxygen content was increased. However, the destruction of the tubular structure led to poor electrochemical properties. These results proved the importance of the thin-walled tubular structure to the electrochemical properties. Surely, this strategy for preparing thin-walled carbon nanotubes can be widely extended to the preparation of other nanomaterials with thin-walled structures.