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Rechargeable aqueous Zn/S batteries exhibit high capacity and energy density. However, the long-term battery performance is bottlenecked by the sulfur side reactions and serious Zn anode dendritic growth in the aqueous electrolyte medium. This work addresses the problem of sulfur side reactions and zinc dendrite growth simultaneously by developing a unique hybrid aqueous electrolyte using ethylene glycol as a co-solvent. The designed hybrid electrolyte enables the fabricated Zn/S battery to deliver an unprecedented capacity of 1435 mAh g-1 and an excellent energy density of 730 Wh kg-1 at 0.1 Ag-1 . In addition, the battery exhibits capacity retention of 70% after 250 cycles even at 3 Ag-1 . Moreover, the cathode charge-discharge mechanism studies demonstrate a multi-step conversion reaction. During discharge, the elemental sulfur is sequentially reduced by Zn to S2- ( S8→Sx2-→S22-+S2-)${{\rm{S}}_8}{\bm{ \to }}{\rm{S}}_{\rm{x}}^{2{\bm{ - }}}{\bm{ \to }}{\rm{S}}_2^{2{\bm{ - }}}{\bm{ + }}{{\rm{S}}^{2{\bm{ - }}}})$ , forming ZnS. On charging, the ZnS and short-chain polysulfides will oxidize back to elemental sulfur. This electrolyte design strategy and unique multi-step electrochemistry of the Zn/S system provide a new pathway in tackling both key issues of Zn dendritic growth and sulfur side reactions, and also in designing better Zn/S batteries in the future. Agency for Science, Technology and Research (A*STAR) National Research Foundation (NRF) The authors acknowledge the grant from the National Research Foundation of Singapore (NRF) Investigatorship Award NRFI2017-08/NRF2016NRF-NRFI001-22 and A*STAR under the Advanced Manufacturing and Engineering (AME) programmatic fund number A20H3g2140.

International audience; This paper investigates the impact of gender quotas on firm performance using countries worldwide that have introduced a gender quota as a quasi-natural experiment. Our statistical analysis shows that board members’ characteristics significantly change after implementing the gender quota. The results of our empirical analysis provide evidence that gender quotas reduce the cost of equity in the short term but decrease the Tobin’s Q in the long term and have a neutral impact on profitability in the short term and the longer term. Our findings support the argument that policymakers can force firms to achieve a gender-balanced representation on corporate boards through a mandatory quota without generating adverse effects on their performance in the short term; however, a negative impact on their Tobins’ Q can be expected in the long term. Our results also suggest that policymakers create unrealistic expectations for women to boost firm performance.

PurposeThe authors examine whether the uncertainty avoidance culture and the stringency of government response play a role in shaping the stock market's response to coronavirus disease 2019 (COVID-19). The authors find that investors' response to the pandemic will not only depend on their instinct of uncertainty aversion but also on their expectation about the effectiveness of the government measures. The uncertainty avoidance culture amplifies the irrational actions of investors. However, harsh government responses will weaken this effect. Harsh government responses also send a negative signal to the market about the extent of the pandemic and the economic damage caused by anti-COVID measures. Governments need to be balanced in imposing anti-COVID measurements to preserve market confidence.Design/methodology/approachIn this article, the authors investigate whether the stock market volatility of emerging countries is simultaneously driven by two factors: the uncertainty-aversion culture of investors in a country and the stringency of the government's response to the pandemic. The authors conduct an empirical study on a sample of 20 emerging countries during the period from January 2020 to March 2021.FindingsThe authors find that the national-level uncertainty aversion amplifies the irrational actions of investors during the period of crisis. However, harsh government responses will weaken this effect. The authors’ findings show evidence that investors' response to the pandemic will not only depend on their instinct of uncertainty aversion but also on their expectation about the effectiveness of the government measures. Although harsh government responses can stabilize the investors' sentiment in countries with high levels of uncertainty aversion, they also send a negative signal to the market about the extent of the pandemic as well as the economic damage caused by anti-COVID measures.Originality/valueFirst, the study’s results complement evidence from existing studies on the effect of uncertainty avoidance culture in determining stock market responses to COVID-19. Second, an important difference from previous studies, this paper adds to the behavioral finance literature by showing that investors' investment decisions in the face of economic uncertainty are not driven solely by their cultural values but also by their expectation about the effectiveness of the government policy. During a crisis, when the market has neither rational information nor adequate experience to forecast the future, the government must play an important role in stabilizing investors' sentiment and reactions.

A new phenylethyl glycoside (1), (S)-1-phenylethyl-6-α-L-arabinopyranosyl-β-D-glucopyranoside), and a new dibenzocyclooctadiene lignan (7), Kasuracin A, together with seven known compounds, were isolated and identified from the leaves of Kadsura coccinea. Their structures were determined by analysis of multinuclear and multidimensional nuclear magnetic resonance (NMR), circular dichroism (CD), mass spectrometry, hydrolysis analysis, or comparison to those reported in the literature. Then, all the isolates 1‒9 were evaluated for their inhibitory effects against nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Among them, compounds 2 and 3 were isolated for the first time from this plant and compounds 3, 7, 8, and 9 significantly inhibited NO production with IC50 values of 36.4, 10.2, 12.3, and 21.7 μM, respectively.

A new diterpene (1) along with eight known compounds (2-9) were isolated from Excoecaria agallocha leaves. The structure and relative configuration of new compound were established on the basis of spectroscopic data analysis and confirmed by NMR chemical shifts calculation with DP4+ probability. Cytotoxicity of the isolated compounds were also evaluated.

Phellinus linteus(Berk. & Curt.) Teng mushroom belonging to the genus Phellinusspp., has high medicinal value. This study was carried out with the aim to evaluate the effects of carbon, nitrogen sources, pH, and temperature on the mycelial growth of the P. linteusstrain. The experimental results showed that glucose and casein with concentrations of 2.0 and 0.2% respectively are identified as the most suitable carbon and nitrogen nutrient sources forP. linteus. Conversely, the mycelia of P. linteusare not able to grow on the urea media. Mycelium of P. linteus growths well at 7-10 pH and temperature at 30oC. When mycelia are incubated in these conditions, the rate of mycelial growth of P. linteus reaches 5.0 mm/day with thick density even distribution, and adherence to the substrate firmly.

In this study, hydrogen (H

Organic/molecular crystals have been widely applied in medicine, imaging, explosives, and optoelectronics, but there are very limited methods for controlling their size and shape at the micro- or nanoscale. Herein, we develop solvent exchange as a new synthetic handle for creating complex morphologies in molecular crystals. With mitigated driving force in solution phase, solvent loss or exchange in C60 plates does not lead to structural collapse, but leads to crystal transformation to mesh networks. C70 and tetrakis(4-bromophenyl)ethylene crystals show similar transformation upon solvent exchange. We study the co-solvents and uncover their competing roles in the destabilization of the crystal structure and the on-site crystallization towards rods. This unconventional role of co-solvent is of importance not only for understanding the pore formation and crumbling, but also a new step towards regulating the desolvation and recrystallization processes. Rational transformation of organic crystals would open a new synthetic route for designing complex structures and new properties. Ministry of Education (MOE) This work was supported by the MOE of Singapore (RG 14/13 and RG 5/16), the National Natural Science Foundation of China (No. 21673117), Recruitment Program of Global Experts, Jiangsu Provincial Foundation for Specially-Appointed Professor, start-up fund at Nanjing Tech University (39837102), and SICAM Fellowship from Jiangsu National Synergetic Innovation Center for Advanced Materials.

We derive a Z-score measure reflecting downside bank insolvency risk, drawing on a Chebyshev inequality in terms of the lower semivariance. As then illustrated empirically for US banks, this may provide a useful alternative, or robustness check, to the more commonly used Z-score measure based on the standard Chebyshev inequality.

Senescence is modulated by ORESARA1 (ORE1), a NAC transcription factor that interacts with hormones to fully induce senescence. The At-ore1 gene acts as a suppressor of leaf senescence; however, its exact role in this respect has not been clearly defined. In this study, the function of At-ore1 during leaf senescence was analyzed in soybeans. The precocious leaf senescence of the ore1-1 line was associated with greater chlorophyll loss, leaf necrosis, and redox imbalance in the early vegetative stage during the hyper-accumulation of endogenous abscisic acid (ABA) by enhancing the expression of GmNECD3-related ABA synthesis. At-ore1 induced ABA regulation of the H2O2-GmARF2-GmNAC081 signaling circuit, which relays the At-ore1-induced cell death signal mediation to the caspase-1-like vacuolar processing enzyme (VPE) expression, triggering programmed cell death. In contrast, it was found that At-ore1 functions in IAA to delay leaf-senescence-mediated suppression of the expression of ABA, ROS, and senescence-associated gene 39 (GmSAG39). The IAA-induced GmNAC065 expression controls soybean leaves’ longevity, as discovered by screening At-ore1 expression in ore1-6 for a more stay-green leaf phenotype by helping to increase seed yields. These results uncover a mechanism that modulates ore1 plants’ amplitude expression involved in the ABA/IAA balance in the activation of GmNAC081- or GmNAC065-dependent H2O2 levels, which are crucial in the senescence or delayed leaf senescence of soybeans.

Silica nanoparticles (SiO2 NPs) synthesized by the Stober method were used as drug delivery vehicles. Doxorubicin hydrochloride (DOX·HCl) is a chemo-drug absorbed onto the SiO2 NPs surfaces. The DOX·HCl loading onto and release from the SiO2 NPs was monitored via UV-VIS and fluorescence spectra. Alternatively, the zeta potential was also used to monitor and evaluate the DOX·HCl loading process. The results showed that nearly 98% of DOX·HCl was effectively loaded onto the SiO2 NPs’ surfaces by electrostatic interaction. The pH-dependence of the process wherein DOX·HCl release out of DOX·HCl-SiO2 NPs was investigated as well. For comparison, both the free DOX·HCl molecules and DOX·HCl-SiO2 NPs were used as the labels for cultured cancer cells. Confocal laser scanning microscopy images showed that the DOX·HCl-SiO2 NPs were better delivered to cancer cells which are more acidic than healthy cells. We propose that engineered DOX·HCl-SiO2 systems are good candidates for drug delivery and clinical applications.

Atomically thin layers of transition-metal dichalcogenides semiconductors, such as MoS2, exhibit strong and circularly polarized light emission due to inherent crystal symmetries, pronounced spin-orbit coupling, and out-of-plane dielectric and spatial confinement. While the layer-by-layer confinement is well-understood, the understanding of the impact of in-plane quantization in their optical spectrum is far behind. Here, we report the optical properties of atomically thin MoS2 colloidal semiconductor nanocrystals. In addition to the spatial-confinement effect leading to their blue wavelength emission, the high quality of our MoS2 nanocrystals is revealed by narrow photoluminescence, which allows us to resolve multiple optically active transitions, originating from quantum-confined excitons (coupled electron-hole pairs). Surprisingly, in stark contrast to monolayer MoS2, the luminescence of the lowest-energy levels is linearly polarized and persists up to room temperature, meaning that it could be exploited in a variety of light-emitting applications.

Multifunctional theranostic nanoagents are attractive to realize comprehensive imaging and effective treatment of tumours. Herein, a novel strategy is developed to controllably guide the epitaxial growth of gold nanostructures onto MoS2 nanosheets. The as-prepared MoS2-Au nanostructures (MA) manifest an enhanced near-infrared (NIR) absorbance with strong photostability. After modification, the obtained MA-PEG shows strong X-ray attenuation and photothermal conversion ability, promising for CT and photoacoustic imaging with an enhanced intensity in tumours. Moreover, in vivo photothermal and radiation therapy with MA-PEG achieves synergistic tumour treatment efficiency through hyperthermia elevated oxygenation level and sensitized radiation therapy. This work illustrates the development of a unique MA nanostructure with enhanced NIR absorbance and strong photoelectric absorbance as a multifunctional theranostic agent with great potential for dual-modal imaging-guided photothermal-radiation therapy of cancer.

A new diterpene (

Supplemental material, sj-docx-1-npx-10.1177_1934578X211055013 for Dispolongiosides A and B, Two New Fucose Containing Spirostanol Glycosides From the Rhizomes of Disporopsis longifolia Craib., and Their Nitric Oxide Production Inhibitory Activities by Tran Thi Thu Ha, Dang Kim Vui, Nguyen Huy Hoang, Bui Huu Tai and Phan Van Kiem in Natural Product Communications

Multinary layered 2D nanomaterials can exhibit distinct physicochemical properties and innovative applications as compared to binary 2D nanomaterials due to their unique crystal structures. However, it still remains a challenge for the high-yield preparation of high-quality multinary 2D nanosheets. Here, the high-yield and large-scale production of two quaternary metal thiophosphate nanosheets are reported, i.e., Ni

This paper compares the distortionary impact of larceny theft across different product markets, characterizing such crime as a “hidden tax” on producers or consumers. We estimate the size of this tax and how it is affected by exogenous changes in larceny rates driven by the enactment of higher felony larceny thresholds. Pre-enactment hidden tax rates are small, ranging from 0.1 percent to 0.4 percent. These tax rates rise or fall with enactment, varying by product market. Such exogenous changes in the hidden tax induce state-level annual welfare changes that are minimal, ranging from –$1,500 to $4,700 across product markets.

Layered van der Waals (vdW) materials, consisting of atomically thin layers, are of paramount importance in physics, chemistry, and materials science owing to their unique properties and various promising applications. However, their fast and large‐scale growth via a general approach is still a big challenge, severely limiting their practical implementations. Here, we report a universal method for rapid (~60 min) and large‐scale (gram scale) growth of phase‐pure, high‐crystalline layered vdW materials from their elementary powders via microwave plasma heating in sealed ampoules. This method can be used for growth of 30 compounds with different components (binary, ternary, and quaternary) and properties. The ferroelectric and transport properties of mechanically exfoliated flakes validate the high crystal quality of the grown materials. Our study provides a general strategy for the fast and large‐scale growth of layered vdW materials with appealing physiochemical properties, which could be used for various promising applications.

Ce papier examine les facteurs qui amènent les banques européennes avec un actionnariat concentré à intégrer des administrateurs minoritaires dans leur Conseil d'Administration, c’est-à-dire des administrateurs reliés aux actionnaires minoritaires. En réalisant une analyse empirique sur un échantillon de banques européennes avec un actionnariat concentré sur la période 2011-2017, nous trouvons que plus les gros actionnaires ont un pouvoir décisionnaire important, plus la proportion d’administrateurs minoritaires augmente. Nous mettons également en évidence que les gros actionnaires favorisent la présence d’administrateurs minoritaires quand le degré d’opacité de la banque est important et quand le niveau de protection des actionnaires du pays est élevé.

Metastable 1T′-phase transition metal dichalcogenides (1T′-TMDs) with semi-metallic natures have attracted increasing interest owing to their uniquely distorted structures and fascinating phase-dependent physicochemical properties. However, the synthesis of high-quality metastable 1T′-TMD crystals, especially for the group VIB TMDs, remains a challenge. Here, we report a general synthetic method for the large-scale preparation of metastable 1T′-phase group VIB TMDs, including WS2, WSe2, MoS2, MoSe2, WS2xSe2(1−x) and MoS2xSe2(1−x). We solve the crystal structures of 1T′-WS2, -WSe2, -MoS2 and -MoSe2 with single-crystal X-ray diffraction. The as-prepared 1T′-WS2 exhibits thickness-dependent intrinsic superconductivity, showing critical transition temperatures of 8.6 K for the thickness of 90.1 nm and 5.7 K for the single layer, which we attribute to the high intrinsic carrier concentration and the semi-metallic nature of 1T′-WS2. This synthesis method will allow a more systematic investigation of the intrinsic properties of metastable TMDs. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version H.Z. acknowledges support from ITC via the Hong Kong Branch of National Precious Metals Material Engineering Research Center (NPMM), the Start-Up Grant (project no. 9380100) and grants (project nos. 9610478 and 1886921) from the City University of Hong Kong and the Science Technology and Innovation Committee of Shenzhen Municipality (grant no. JCYJ20200109143412311). Q.H. acknowledges the funding support from the Start-Up Grant (project no. 9610482) from the City University of Hong Kong. Y.S. and Y.M. acknowledge the funding support from the National Natural Science Foundation of China (under grant no. 11534003) and the Program for JLU Science and Technology Innovative Research Team and Science Challenge Project (no. TZ2016001). K.H. and D.V.M.R. acknowledge funding from the Accelerated Materials Development for Manufacturing Program at A*STAR via the AME Programmatic Fund by the Agency for Science, Technology and Research under grant no. A1898b0043. R.V.R. and V.S. acknowledge support by grants from the National Research Foundation, Prime Minister’s Office, Singapore, under its Campus for Research Excellence and Technological Enterprise (CREATE) programme. X.R.W. acknowledges supports from Academic Research Fund Tier 2 (grant no. MOE-T2EP50120-006) from Singapore Ministry of Education.

As a source of clean energy, a reliable hydrogen evolution reaction (HER) requires robust and highly efficient catalysts. Here, by combining chemical vapor transport and Li-intercalation, we have prepared a series of 1T′-phase ReS2xSe2(1-x) (x = 0–1) nanodots to achieve high-performance HER in acid medium. Among them, the 1T′-phase ReSSe nanodot exhibits the highest hydrogen evolution activity, with a Tafel slope of 50.1 mV dec–1 and a low overpotential of 84 mV at current density of 10 mA cm–2. The excellent hydrogen evolution activity is attributed to the optimal hydrogen absorption energy of the active site induced by the asymmetric S vacancy in the highly asymmetric 1T′ crystal structure. MOE (Min. of Education, S’pore)

Declines in physiological functions are the predominant risk factors for age-related diseases, such as cancers and neurodegenerative diseases. Therefore, delaying the aging process is believed to be beneficial in preventing the onset of age-related diseases. Previous studies have demonstrated that Graptopetalum paraguayense (GP) extract inhibits liver cancer cell growth and reduces the pathological phenotypes of Alzheimer’s disease (AD) in patient IPS-derived neurons. Here, we show that GP extract suppresses β-amyloid pathology in SH-SYS5Y-APP695 cells and APP/PS1 mice. Moreover, AMP-activated protein kinase (AMPK) activity is enhanced by GP extract in U87 cells and APP/PS1 mice. Intriguingly, GP extract enhances autophagy in SH-SYS5Y-APP695 cells, U87 cells, and the nematode Caenorhabditis elegans, suggesting a conserved molecular mechanism by which GP extract might regulate autophagy. In agreement with its role as an autophagy activator, GP extract markedly diminishes mobility decline in polyglutamine Q35 mutants and aged wild-type N2 animals in C. elegans. Furthermore, GP extract significantly extends lifespan in C. elegans.