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By a two-step method, we successfully synthesized a WS 2 /WO 3-x heterostructured catalysts with abundant oxygen vacancies. The WS 2 /WO 3-x -2 heterostructured catalyst demonstrates outstanding HER activity and stability in acidic and alkaline electrolytes. [Display omitted] H 2 produced through hydrogen evolution reaction (HER) is a shining star in the field of clean energy. Significant efforts have been dedicated to develop efficient and stable electrocatalysts to reduce the energy barrier and accelerate the kinetics of Hydrogen evolution reaction (HER) under various environments. Herein, we propose a strategy to accelerate the kinetics of HER under acid and alkaline environments by combining heterostructure engineering with defect engineering. We have successfully synthesized a series of WS 2 /WO 3-x heterostructured catalysts, accompanied with substantial oxygen vacancies using a two-step synthesis method. With the partially sulfurization of WO 3-x , the heterojunction interface of WS 2 and WO 3-x was formed along with the appearance of oxygen vacancies, which can facilitate the migration of electrons. The heterostructured catalyst enriched with oxygen vacancies (defined as WS 2 /WO 3-x -2) demonstrates superior HER performance in acidic and alkaline electrolytes. At a current density of 10 mA cm−2, the WS 2 /WO 3-x -2 heterostructured catalyst manifests an overpotential of 120 mV in the acidic electrolytes and a slightly higher overpotential of 150 mV in an alkaline environment. The overpotentials offer an improvement compared to reported W-based catalysts in terms of HER performance. This work provides guiding significance on the design of heterostructured catalysts with promising performance for HER in acidic and alkaline environments. [ABSTRACT FROM AUTHOR]

An La–BiOCl/layered double hydroxide (LDH) composite photocatalyst was prepared with a hydrothermal method by using Bi(NO 3) 3 ·5H 2 O and La(NO 3) 3 ·6H 2 O as precursors and LDHs as a support. The photocatalytic performance of the materials was evaluated by taking tetracycline (TC) hydrochloride as the target pollutant. The results show that La3+ enters the BiOCl lattice and replaces Bi3+ to form an La–O–Bi bond after loading La–BiOCl onto the hydrotalcite. The surface area of the material is 42.5733 ​m2/g, the average particle size is 13.5371 ​nm, the optical absorption threshold is increased from 374.6 ​nm to 472.9 ​nm, and the bandgap width is 2.62 ​eV. Under irradiation by a visible light source, the rate of removal of TC hydrochloride is increased from 49.6% to 79.8% within 2 ​h. The photocatalytic degradation process is governed by a first-order kinetic model. [Display omitted] • La-BiOCl /LDHs photocatalyst was prepared by hydrothermal method, and its photocatalytic effect on TC was further evaluated. • The width of the band gap is reduced from 3.31 ​eV to 2.62 ​eV. • Under the optimal conditions, the removal rate of TC is 79.8%, and the reuse performance is good. [ABSTRACT FROM AUTHOR]

We propose a novel sacrificial solvent method and synthesized Co 9 S 8 /Ni 3 S 2 @NF heterostructure catalyst, which exhibited excellent oxygen evolution reaction activity in alkaline environment. [Display omitted] Synthesizing catalysts for efficient oxygen evolution reaction (OER) with lower cost and simpler design is of significant importance to achieve sustainable hydrogen production. In this work, we propose a novel "sacrificial solvent method" for the first time. Dicobalt octacarbonyl (Co 2 (CO) 8), dimethyl sulfoxide (DMSO), and Ni foam (NF) were used as the raw materials in the solvothermal process. DMSO played the role of both the sacrificial solvent and the sulfur source. Through the self-consumption of DMSO, we finally obtained the Co 9 S 8 /Ni 3 S 2 heterostructure supported on the NF (Co 9 S 8 /Ni 3 S 2 @NF) in one step. The Co 9 S 8 /Ni 3 S 2 @NF catalyst exhibited excellent OER activity in alkaline environment, with an overpotential of only 264 mV at a current density of 20 mA cm−2, a low Tafel slope of 68.28 mV dec-1 and maintained its current density after 20 h of constant potential testing. This work introduces a new method for synthesizing metal sulfide catalysts using DMSO as a sacrificial solvent. It provides broader opportunities for the development of more efficient and sustainable catalysts for energy conversion and storage. [ABSTRACT FROM AUTHOR]

Abstract: The stearoyl-acyl carrier protein desaturase (SAD) gene widely exists in all kinds of plants. In this paper, the Camellia sinensis SAD gene (CsSAD) sequence was firstly analyzed by Codon W, CHIPS, and CUSP programs online, and then compared with genomes of the tea plant, other species and SAD genes from 11 plant species. The results show that the CsSAD gene and the selected 73 of C. sinensis genes have similar codon usage bias. The CsSAD gene has a bias toward the synonymous codons with A and T at the third codon position, the same as the 73 of C. sinensis genes. Compared with monocotyledons such as Triticum aestivum and Zea mays, the differences in codon usage frequency between the CsSAD gene and dicotyledons such as Arabidopsis thaliana and Nicotiana tobacum are less. Therefore, A. thaliana and N. tobacum expression systems may be more suitable for the expression of the CsSAD gene. The analysis result of SAD genes from 12 plant species also shows that most of the SAD genes are biased toward the synonymous codons with G and C at the third codon position. We believe that the codon usage bias analysis presented in this study will be essential for providing a theoretical basis for discussing the structure and function of the CsSAD gene. [Copyright &y& Elsevier]

Abstract: The toxic effects of Aroclor 1254 (0.05, 0.5, 5 and 50μgl−1) on scallop (Chlamys farreri) immune system in vivo were studied. The results showed that Aroclor 1254 had significant toxic effect on the parameters tested in this paper (P <0.05). The total number of haemocytes, the proportion of granulocytes, phagocytosis in all groups as well as the lysosomal membrane stability (LMS) in 5, 50μgl−1 and bacteriolytic activity 0.5, 5, 50μgl−1 treatments decreased significantly, while the proportion of hyalinocytes and the production of O2 - in all treatments remarkably increased during the sampling time and tended to be stable gradually after 6–15d. The bacteriolytic activity in 0.05μgl−1 treatments, LMS in 0.05, 0.5μgl−1 groups and the DNA damage (comet ratios and arbitrary values) in all treatments increased at the beginning of exposure and reached their peaks on day 1, day 1, day 6 and day 3, following that they all decreased gradually and became stable after 9–15d. When the indices reached stability, except for DNA damage was higher than controls, the others were all significantly lower than those of controls (P <0.05). Thus, Aroclor 1254 has evident toxic effects on scallop immune system, which supports the view that a relationship exists between pollution and immunomodulation in aquatic organisms. Also it supports the speculation that the PCBs pollution is one of the important reasons of the mass mortality of the C. farreri. [Copyright &y& Elsevier]

Visible-near-infrared reflectance spectra reveal clues about the mineralogy and composition of planetary surfaces. In most cases, light interacts with a mixture of various components on planetary surfaces. While radiative transfer models have been developed to simulate mixture in particulate surfaces, the extent to which spectral features represent the bulk composition of rock remains unclear. In this study, we present the analysis of a new dataset with hyperspectral imaging of rock slabs at different resolutions to characterize the scaling of spectral data. We address the problem of spectral mixing with high-resolution imaging of Martian meteorite NWA480 at a microscopic scale. The linear combination of each pixel provide an approximate to the rock's bulk spectra. However, we find the impurities, fractures and zoning create wide spectral variability in the mineral crystals. In addition, the widespread opaque minerals may also darken the spectra, resulting in non-unique interpretation of the bulk spectra. These complexities in the natural samples prevent an accurate mineral abundance retrieval using unmixing algorithms with select spectral endmembers. We suggest applying recently developed algorithms on unmixing with spectral variability with the consideration of the petrologic context would be necessary to improve the quantitative analysis of planetary surfaces. • Spectral images of a Martian meteorite are analyzed to test spectral mixing models. • Large spectral variability is found in the pyroxene phenocrysts of the same sample. • There is a tradeoff between the reflectance and the dark component abundance. • Physical and chemical imperfections may cause the spectral variability observed. [ABSTRACT FROM AUTHOR]

Abstract: Water temperature changes (higher and lower than 24°C) were shown to have a significant effect on dopamine (DA) concentration, haemocyte count and the proPO system in the white shrimp Litopenaeus vannamei. No significant difference in any of the parameters was observed in the control group. DA concentration in haemolymph in the experimental groups increased to a peak value at 0.5 days; meanwhile serine protease (SP) activity and proteinase inhibitor (PI) activity decreased. Total haemocyte count (THC), differential haemocyte count (DHC) and PO activity were lowest at 1 day. All defence parameters became stable after 1–3 days, while the total haemocyte and large granular cell count stabilized after 6 days. After these stabilized, there was no significant difference in DA concentration and PI activity between the control and experimental groups, as was the case for the THC, DHC, PO and SP activities of shrimp held at higher temperatures. However these latter four parameters in the lower temperature groups were distinctly lower than the control group. α2-Macroglobulin activity in the experimental groups increased to a peak value after 1 day compared with the control and then stabilized after 6 days when the activity levels in higher temperature groups were higher than the control, while the lower temperature groups had no significant difference from the control. It was therefore concluded that water temperature changes modulated the immune system of L. vannamei. [Copyright &y& Elsevier]

InSight landed on Mars on November 26, 2018, in western Elysium Planitia. The Mars crust beneath the lander is subject to complex geologic history next to the great topographic and crustal dichotomy of Mars. Understanding this part of the Martian crust in the subsurface would aid future investigations of the internal structure of the planet based on seismic datasets collected by the Seismic Experiment for Interior Structure (SEIS) instrument. Here, we investigate the subsurface structure and composition from the analysis of mineralogy and morphology of exposures in impact craters as well as on scarps and knobs in the general region of Elysium Planitia. Using a combination of orbital datasets, we identify exposures of subsurface materials with distinct composition and physical properties. We find olivine and pyroxene detections associated with small impact craters (1.5–7 km) rim in the vicinity of InSight lander, as well as in the transition unit and Elysium volcanic unit. Fe/Mg phyllosilicates have been identified in the central peak of the 51-km diameter Kalpin crater and on knobs in the transition unit between the dichotomy and the plains. In addition, eroded meter-scale layered unit subject to erosion has been identified in six impact craters to the north-east of the landing site, including Kalpin crater. Massive bedrock and layered, weak materials co-occur in the transition unit, indicating a complex origin. These results together suggest both materials with altered composition and layered deposit occur as distinct geologic units beneath the basaltic lava flow units. Through analogy with terrestrial sedimentary rocks or clay-bearing sediments, we suggest physically weak materials exist beneath the lava flow units in the general region of Elysium Planitia. The spatial distribution and continuity of these materials are unclear due to the lack of exposures within the lava flow unit where the InSight lander is located. These subsurface materials of distinct physical properties may result in increased attenuation or reverberations of seismic waves, to be collected by SEIS. The findings suggest a close investigation of the potential effects of subsurface stratigraphy on seismic data would help inform future data interpretation and understanding of the internal structure of Mars. • Kalpin crater north of the InSight landing site exposes a phyllosilicate-bearing unit beneath the lava flows. • Layered, yardang-forming materials near the landing site indicate extended sedimentary unit in the subsurface. • Heterogeneous composition and structure with possible weak layers could affect the seismic signal acquired by InSight. [ABSTRACT FROM AUTHOR]

Background Associations of ambient temperature with cardiovascular morbidity and mortality have been well documented in numerous epidemiological studies, but the underlying pathways remain unclear. We investigated whether systemic inflammation, coagulation, systemic oxidative stress, antioxidant activity and endothelial function may be the mechanistic pathways associated with ambient temperature. Methods Forty study participants underwent repeated blood collections for 12 times in Beijing, China in 2010–2011. Ambient temperature and air pollution data were measured in central monitors close to student residences. We created five indices as the sum of weighted biomarker percentiles to represent the overall levels of 15 cardiovascular biomarkers in five pathways (systemic inflammation: hs-CRP, TNF-α and fibrinogen; coagulation: fibrinogen, PAI-1, tPA, vWF and sP-selectin; systemic oxidative stress: Ox-LDL and sCD36: antioxidant activity: EC-SOD and GPX1; and endothelial function: ET-1, E-selectin, ICAM-1 and VCAM-1). We used generalized mixed-effects models to estimate temperature effects controlling for air pollution and other covariates. Results There were significant decreasing trends in the adjusted means of biomarker indices over the lowest to the highest quartiles of daily temperatures before blood collection. A 10 °C decrease at 2-d average daily temperature were associated with increases of 2.5% [95% confidence interval (CI): 0.7, 4.2], 1.6% (95% CI: 0.1, 3.1), 2.7% (95% CI: 0.5, 4.8), 5.5% (95% CI: 3.8, 7.3) and 2.0% (95% CI: 0.3, 3.8) in the indices for systemic inflammation, coagulation, systemic oxidative stress, antioxidant activity and endothelial function, respectively. In contrast, the associations between ambient temperature and individual biomarkers had substantial variation in magnitude and strength. Conclusions The altered cardiovascular biomarker profiles in healthy adults associated with ambient temperature changes may help explain the temperature-related cardiovascular morbidity and mortality. The biomarker index approach may serve as a novel tool to capture ambient temperature effects. [ABSTRACT FROM AUTHOR]

Impact craters are widely used to investigate the geologic history of planetary surfaces. Their morphology bears clues on past surface processes that affected it such as erosion, sedimentary deposit and volcanic processes and their density is widely used to date planetary surfaces. In this study we propose to combine crater Density and morphology into a single representation, Crater Size and Depth Frequency Distribution (CSDFD) that offers a snapshot not only at the age but also at the obliteration history of the crater population. Using simple models, we interpreted the CSDFD in term of crater obliteration rates. This methods can be applied on any body featuring impact craters. We present here the results obtained on Mars, using a global crater database. The obliteration rates obtained from CSDFD are consistent with known geologic history of Mars. Reaching thousands of m/Gy during Noachian and rapidly dwindling as soon as 3.5 Gy. Moreover, our method highlighted an continuous activity of Northern Lowlands surface during Amazonian we interpret to be linked with the formation of the vastitas borealis formation. This study offer a continuous vision in time and space of Martian obliteration history. • Crater Size and Depth Frequency Distribution (CSDFD) represents a crater population. • We compute crater obliteration rates from CSDFD. • Martian obliteration rates decrease during Noachian. • Martian volcanism highly obliterates craters during Hesperian. [ABSTRACT FROM AUTHOR]

The cardiopulmonary effects of chemical constituents and sources of indoor fine particulate matter (PM 2.5) remain unclear. To examine the individual and joint effects of constituents of indoor PM 2.5 on cardiopulmonary function of patients with chronic obstructive pulmonary disease (COPD) and the role of identified sources. This panel study recruited 43 stable COPD patients from November 2015 to May 2016 in Beijing, China. Daily indoor and outdoor PM 2.5 were collected for five consecutive days simultaneously. Twenty-four elements were measured and principal component analysis was used for source appointment. Pulmonary function and blood pressure (BP) were also measured at daily visit. The linear mixed-effect models were used to estimate the effect of each constituent and source. Bayesian kernel machine regression (BKMR) models were used to estimate the overall effect of all measured constituents. The combustion, indoor soil/dust and road dust sources were identified as the main sources of indoor PM 2.5 and combustion sources contributed over 40% during the heating season. Most constituents were significantly associated with elevated BP of COPD patients and the joint effects of mixed exposures were also significant especially during the heating season. Most associations of chemical constituents with pulmonary function were negative but not statistically significant during the heating season, as was the joint effect. Few associations were observed during the non-heating season. Further, we observed combustion sources throughout the study period and road dust sources during the heating season were significantly associated with increased BP but not decreased pulmonary function. The combustion and road dust sources and their related constituents of indoor PM 2.5 could cause adverse effects on cardiovascular function of COPD patients especially during the heating season, but the effect on pulmonary function still needs to be further studied. • The sources of indoor PM 2.5 and their contribution in different seasons were identified. • Cardiopulmonary effects of indoor PM 2.5 constituents and sources were estimated. • This is the first study to assess the joint effect of multiple PM 2.5 constituents. • The cardiovascular effect of indoor PM 2.5 constituents was stronger than respiratory. • The cardiovascular effects of combustion and road dust sources may merit attention. [ABSTRACT FROM AUTHOR]

Abstract Previous work has confirmed that the chronic hypoxia-hypercapnia (CHH) associated with chronic obstructive pulmonary disease contributes to the development of skeletal muscle atrophy. Neuromuscular Electrical Stimulation (NMES) has shown some efficacy when used as a treatment to reduce skeletal muscle atrophy. The present study focuses on the MicroRNA-486/PTEN/FoxO1 pathway with the goal of identifying its physiological role in skeletal muscle atrophy induced by CHH as well as its role during NMES treatment. To test this, 32 male Sprague Dawley rats were randomly divided into four groups. After completion of the disease modeling, gastrocnemius muscles were collected from all animals and cross-sectional areas of muscular fiber were observed and analyzed via H&E staining. MiR-486 expression was further assessed by qRT-PCR, and protein levels of TNF-α, PTEN, p -Akt, Akt, FoxO1, atrogin-1 and MuRF1 were measured by immunohistochemistry and western blotting. CSA, miR-486, and the ratio p -Akt/Akt were significantly reduced in the CHH group, while the levels of TNF-α, PTEN, FoxO1, atrogin-1, and MuRF1 were markedly increased. Importantly, these findings were reversed as a result of NMES. Thus, the MicroRNA-486/PTEN/FoxO1 pathway functions in muscle protein synthesis and degradation. New & Noteworthy Our research provides a theoretical basis for the application of NMES as a means of improving muscle atrophy. Moreover, these therapeutic targets provide possible clues relevant to the treatment of amyotrophic diseases. Highlights • Chronic hypoxia-hypercapnia promoted expression of this inflammatory cytokine, whereas NMES exerted an anti-inflammatory effect to reduce its expression. • Under condition of chronic hypoxia-hypercapnia, decreasing miR-486 levels relieved the repression of PTEN and Foxo1a translation. • NMES effectively promoted the transcription of miR-486, which in turn resulted in enhanced repression of PTEN and Foxo1a translation. [ABSTRACT FROM AUTHOR]

Abstract Background Metro system has become popular in urban areas. However, short-term effects of size-fractionated particulate matter (PM) on cardiac autonomic function in metro system remain unexplored. Objectives To explore the contribution of ambient PM to in-cabin PM and investigate the short-term effects of exposure to size-fractionated PM and black carbon (BC) in metro system on cardiac autonomic function in young healthy adults. Methods Thirty nine young healthy adults were asked to travel in metro system during 9:00–13:00 on a weekends between March and May 2017. We performed continuous ambulatory electrocardiogram monitoring for each of them, and measured real-time size-fractionated PM, BC, nitrogen dioxide, nitric oxide, carbon dioxide, ozone, noise, temperature and relative humidity in metro cabin. We also collected the data of ambient PM 2.5 (aerodynamic diameter < 2.5 µm) concentrations in Beijing. Linear regression model was used to estimate the infiltration factor of ambient PM 2.5 to assess the relationship between metro cabin PM and ambient PM. Mixed-effects model was used to estimate the associations between changes in HRV parameters and PM 0.5 (aerodynamic diameter < 0.5 µm), PM 0.5–2.5 (aerodynamic diameter between 0.5 µm and 2.5 µm), PM 2.5–10 (aerodynamic diameter between 2.5 µm and 10 µm), and BC, respectively. Results We found that size-fractionated PM in metro systems were significantly associated with HRV parameters. Per IQR (interquartile range) increase in PM 0.5 (1.6*107/m3) in 1-h moving average concentration was associated with a 13.96% (95% CI: − 18.99%, − 8.61%) decrease in SDNN (standard deviation of normal-to-normal intervals). Similar inverse associations were found between size-fractionated PM exposure and LF (low frequency power), HF (high frequency power), respectively, and smaller particles had greater effects on HRV parameters at shorter lag time. Sex of participants modified the adverse associations between size-fractionated PM and HRV. An IQR of 1-h PM 0.5 increasing was associated with a decrease of 6.05% (95% CI: − 22.87%, − 14.44%) in males and a 34.87% (95% CI: − 49.59%, − 15.85%) in females in LF (P for interaction = 0.026). The infiltration factor of ambient PM 2.5 was 0.39 (95% CI: 0.33, 0.45). It is estimated that PM 2.5 originated from ambient air may account for 20.2% of the PM measured in metro cabin. Per IQR increase in BC (5.5 μg/m3) in 5-min, 1-h, and 2-h moving averages, a primary tracer for ambient PM from combustion source, was associated with decreases of 0.84% (95% CI: − 1.20%, − 0.47%), 2.22% (95% CI: − 3.20%, − 1.22%), and 4.44% (95% CI: − 6.28%, − 2.56%) in SDNN, respectively. Conclusions Short-term exposure to PM may disturb metro commuter's cardiac autonomic function, and the potential effects depend on the size of PM and the sex of commuters. Ambient PM from combustion source may have adverse effects on the cardiac autonomic function of passengers in cabin. Highlights • Exposure to metro PM was associated with decreased HRV in young healthy adults. • The strength and lag time for effects of PM on HRV varied by particle size. • Greater decreases in HRV suggested that females were more susceptible to the effects of PM exposure. • Ambient PM from combustion source (indicated by black carbon) has adverse health effects on passengers in cabin. [ABSTRACT FROM AUTHOR]

• Two new diterpenes were identified from Isodon interruptus. • The new seco-abietane diterpene was designated as 9, 10-seco-neoabietane. • The neoabietane diterpene showed chemopreventive potential by inducing QR1 activity. • The new ent -kaurene diterpene displayed cancer cell killing activities. • The chemical structures were confirmed by the X-ray crystallographic data. In the course of our ongoing studies to discover bioactive chemical constituents from plants in the genus Isodon , two new diterpenes, kunminolide A (1) and rabdokunmin F (2) were isolated from the leaves of the medicinal plant Isodon interruptus. Kunminolide A (1) is a novel abietane-like diterpene with a novel skeleton, herein designated as 9, 10-seco-neoabietane. Rabdokunmin F (2) is an ent -kaurene diterpene with C-18 oxidized to a carboxylic acid group. The structures were determined by spectroscopic means including analysis of 1D- and 2D-NMR spectral data. Crystals of 1 obtained from methanol were suitable for X-ray analysis, which confirmed the chemical structure. Kunminolide A (1) demonstrated chemopreventive potential by inducing QR1 activity with a CD value of 14.3 µM, and rabdokunmin F (2) was found to have cytotoxic activities with IC 50 values in the range of 1.1–3.0 µM. [ABSTRACT FROM AUTHOR]