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Abstract Objective Oxidized Low-Density-Lipoprotein (Ox-LDL) is the core factor in the development of atherosclerosis. However, there are few therapies aimed at eliminating Ox-LDL. Here in this study, we investigate whether the ectopically expression of the lectin-like oxidized low density lipoprotein receptor (LOX-1) in the liver could lead to the elimination of circulating Ox-LDL and prevent the deposition in the vascular wall, thereby alleviating the progression of atherosclerosis. Methods Apolipoprotein E-deficient (ApoE−/−) mice were randomly divided into three groups, the control group, the AAV8-TBG-eGFP group (eGFP group) and AAV8-TBG-LOX-1 group (LOX-1 group). In the LOX-1 group, mice received an injection of virus dilution AAV8-TBG-LOX-1 (1.16 × 1011 virus genome (v.g)/animal/100 μl). The mice in the control group and eGFP group received the same amount of sterile saline and AAV8-TBG-eGFP virus dilution injections. The expression of LOX-1 in the liver was detected by immunofluorescent, western blot and immunohistochemistry. The safety of the virus was assessed by hematoxylin–eosin (H&E) staining, blood biochemical analyses and immunofluorescent. The function of LOX-1 in the liver was detected by the co-localization of LOX-1 and Dil-labeled Ox-LDL (Dil-Ox-LDL) under laser scanning confocal microscope. The extent of Ox-LDL in plasma was detected by ELISA. Changes in blood lipids were assessed through blood biochemical analysis. The progression of atherosclerotic lesions was detected by Oil red O staining. And the expression of Vascular Cell Adhesion Molecule-1 (VCAM-1) in endothelial cells and the extent and migration of macrophages in atherosclerotic plaque were detected by immunofluorescence staining. The protein expression in liver was assessed by qRT-PCR and western blot. Results The expression of LOX-1 was stable in liver within 4 weeks. Ectopically expressed LOX-1 in the liver phagocytosed and degraded Ox-LDL and reduced Ox-LDL from circulation but did not have a significant effect on blood lipid levels. After the expression of LOX-1 in liver, Ox-LDL can be cleared by the hepatocytes, thereby reducing VCAM-1 expression in vascular endothelium and the migration of macrophages in plaques, and eventually alleviating the progression of atherosclerosis. Functional expression of LOX-1 in hepatocytes may facilitate the metabolic clearance of Ox-LDL by upregulating the expression of ATP-binding cassette G5 and G8 (ABCG5/G8), which is the primary neutral sterol transporter in hepatobiliary and transintestinal cholesterol excretion. Conclusion Ectopic liver-specific expression of LOX-1 receptor alleviates the progression of atherosclerosis by clearing Ox-LDL from circulation.

Ruthenium (Ru) single atoms were decorated on the surface of the graphitic carbon nitride (g-C3N4) successfully in this work. By varieties of characterization, the existence of Ru single atoms and the defects (cyano groups) caused in the process of synthesis have been confirmed. The catalyst decorated by Ru atoms (Ru-CCN-0.05) had better absorption capacity and a wider absorption range of light than the catalyst with no Ru atoms loading on (Ru-CCN-0). Without the help of hole-scavengers, the rate of photocatalytic nitrogen fixation of Ru-CCN-0.05 in ultra-pure water was 2.26 mg L−1 gcat −1 h−1, 1.5 times that of bare g-C3N4.

Different grads of magnetic nano-scaled cobalt ferrites (CoFe2O4) photocatalysts were synthesized by modified Solvothermal (MST) process with and without polysaccharide. The indigenously synthesized photocatalysts were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), thermo gravimetric analysis (TGA), Fourier transform infrared (FT-IR), UV–visible (UV–vis) spectroscopy and N2 adsorption–desorption isotherm method. The Fourier transform infrared spectroscopy study showed the Fe-O stretching vibration 590–619 cm−1, confirming the formation of metal oxide. The crystallite size of the synthesized photocatalysts was found in the range between 20.0 and 30.0 nm. The surface area of obtained magnetic nanoparticles is found to be reasonably high in the range of 63.0–76.0 m2/g. The results shown that only MST-2 is the most active catalyst for photo-Fenton like scheme for fast photodegradation action of methylene blue dye, this is possible due to optical band gap estimated of 2.65 eV. Captivatingly the percentage of degradation efficiency increases up to 80% after 140 min by using MST-2 photocatalyst. Photocatalytic degradation of methylene blue (MB) dye under visible light irradiation with cobalt ferrite magnetic nanoparticles followed first order kinetic constant and rate constant of MST-2 is almost 2.0 times greater than MST-1 photocatalyst. Keywords: Cobalt ferrite, Photocatalysis, Kinetics, Optical properties, Surface area studies

Abstract Transition metal sulfides are regarded as a type of high-performance anode materials for lithium ion batteries (LIBs). However, their electrochemical process and lithium-storage mechanism are complicated and remain controversial. This work is intended to give the direct observation on the electrochemical behavior and find out the lithium-storage mechanism of molybdenum disulfide (MoS2) using in situ transmission electron microscopy (TEM). We find that single-crystalline MoS2 nanosheets convert to Mo nanograins (~2 nm) embedded in Li2S matrix after the first full lithiation. After the delithiation, the Mo nanograins and Li2S transform to a large number of lamellar MoS2 nanocrystals. The discharge-charge cycling of MoS2 in LIBs is found to be a fully reversible conversion between MoS2 and Mo/Li2S rather than the electrochemical conversion between S and Li2S proposed by many researchers. The in situ real-time characterization results give direct evidence and profound insights into the lithium-storage mechanism of MoS2 as anode in LIBs.

Depending on specific environmental conditions, Robinia pseudoacacia plantations can have a positive or negative impact on ecosystem function. Numerous studies have demonstrated that R. pseudoacacia plantations on the Loess Plateau has decreased the water levels in this area, increasing the risks of water resource security. Understanding the ecosystem function of the R. pseudoacacia plantations is thought to be critical to vegetation restoration in the Loess Plateau. However, no consensus exists on the mechanism by which afforestation affects moisture regulation under varying environmental conditions nor on how to manage R. pseudoacacia plantations to maintain the ecosystem function. In this study, we used the response–effect trait approach to examine the evolving relationship between community functional composition and water regulation by collecting community samples from R. pseudoacacia plantations and natural ecosystems across three vegetation zones (steppe, forest–steppe, and forest). Our goal was to clarify how the afforestation of R. pseudoacacia impacts functional composition and, consequently, moisture regulation. The findings indicated that R. pseudoacacia negatively impacts community structure and moisture regulation in the drier steppe and forest-steppe (P

Soil and water conservation measures (SWCM) have wide-ranging effects on vegetation and soil, and their effects on the ecosystem are multifaceted, with complex mechanisms. While numerous studies have focused on the impact of such measures on soil, the improvement of plant functional traits is a major factor in the ecological recovery of the Loess Plateau. This survey extensively investigated no measure plots, vegetation measure plots, and engineering measure plots in the Loess Plateau. The impact of SWCM on plant functional traits was investigated using structural equation modeling. We examined six plant functional traits—leaf dry weight (LD), specific leaf area (SLA), leaf tissue density (LTD), leaf total phosphorus (LTP), leaf total nitrogen (LTN), and leaf volume (LV)—correlated with resource acquisition and allocation. In 122 plots, we explored the effects of measures, soil, diversity, and community structure on the weighted average of plant functional traits. The findings showed substantial positive correlations between LD and SLA, LD and LV, SLA and LV, SLA and LTP, and LTP and LTN. LTD has a substantial negative correlation with LD, LTD with SLA, and LTD with LV. SWCM limits diversity, and the mechanisms by which it affects plant functional traits vary. In the structural equation model (SEM) of vegetation measures, improving community structure enhances plant functional traits, but soil factors have the greatest influence on plant functional traits in SEM engineering measures. Plant functional trait differences on the Loess Plateau result are due to differential plant responses to diverse soil properties and community structure. Vegetation measures enhance the chemical properties of plant functional traits, while engineering measures improve physical properties. The study provides a theoretical foundation for vegetation restoration and management following the implementation of diverse SWCM.

Soil moisture is an important component of the soil–vegetation–atmosphere terrestrial hydrological cycle and is an important factor affecting terrestrial ecosystems. In the context of extensive vegetation greening on the Tibetan Plateau (TP), it is important to investigate the effect of vegetation greening on soil moisture to maintain ecosystem stability and protect the sustainability of ecological restoration projects. To evaluate the effect of vegetation greening on soil moisture on the TP, the spatial distribution and trends of soil moisture and vegetation on the TP were analyzed using GIMMS NDVI data and ERA5 soil moisture data from 1982 to 2015. The effects of grassland NDVI, precipitation, and temperature on SM were also explored using multiple regression apparent and SEM. The main results are as follows: from 1982 to 2015, both grassland NDVI and SM showed a stable increasing trend. Precipitation was the most important factor influencing SM changes on the TP. In the context that vegetation greening is mainly influenced by temperature increase, vegetation plays a dominant role in SM changes in soil drying and soil wetting zones. In this paper, the climate–vegetation–soil moisture coupling mechanism of grasslands on the TP is investigated, and the related results can provide some theoretical references and suggestions for global ecosystem conservation and the sustainable development of ecological restoration projects.

Plant functional traits (PFTs) can reflect the response of plants to environment, objectively expressing the adaptability of plants to the external environment. In previous studies, various relationships between various abiotic factors and PFTs have been reported. However, how these factors work together to influence PFTs is not clear. This study attempted to quantify the effects of topographic conditions, soil factors and vegetation structure on PFTs. Four categories of variables were represented using 29 variables collected from 171 herb plots of 57 sites (from different topographic and various herb types) in Xindian SWDP. The partial least squares structural equation modeling showed that the topographic conditions and soil properties also have a direct effect on plant functional traits. Among the topographic conditions, slope (SLO) has the biggest weight of 0.629, indicating that SLO contributed the most to plant functional traits and vegetation structure. Among soil properties, maximum water capacity (MWC) contributes the most and is followed by soil water content (SWC), weighted at 0.588 and 0.416, respectively. In a word, the research provides new points into the quantification of the correlation between different drivers that may be important for understanding the mechanisms of resource utilization, competition and adaptation to the environment during plant recovery.

The lithiation reaction of ZnO as an anode in a lithium-ion battery (LIB) is unclear. The electrochemical behavior of ZnO was investigated inside a transmission electron microscope (TEM) by constructing a nano-LIB using an individual ZnO/graphene sheet as the electrode. The lithiation reaction of ZnO/graphene was monitored by simultaneous determination of the structure with high-resolution TEM, electron diffraction pattern and electron energy-loss spectroscopy. Two kinds of reaction modes were revealed in terms of different reaction rates. One was the violent reaction mode, in which one particle can evolve into an aggregate of many nanoparticles within the Li2O matrix in 1-2 min. The other was the peaceful evolution mode, in which each ZnO nanoparticle evolves into a core-shell particle with multi-domains constituted of Zn and LiZn nanograins. Abnormally large Zn nanocrystals grow quickly in the violent reaction mode, which can suppress the formation of LiZn and impair the reversible capacity. Our observations give direct evidence and important insights for the lithiation mechanism of metal oxide anodes in LIBs. [ABSTRACT FROM AUTHOR]

We demonstrate a new strategy for preparation of ZnO/ZnS core–shell nanorods viamicrowave-assisted in situsurface sulfidation of ZnO nanorods. This is a facile and rapid process, requiring only a low level of microwave irradiation (400 W), through which a conformal ZnS nanoparticle layer is deposited onto the ZnO nanorods, while retaining the uniformity of the original ZnO nanorods in the as-prepared ZnO/ZnS hybrid structures with excellent fidelity. Furthermore, the thickness and nanoparticle size of the ZnS shell can be conveniently varied or controlled by the concentration of the organo-sulfur source thioacetamide (TAA). The as-prepared products exhibit narrowed band gap and strong orange luminescence at 621 nm, due to the interstitial oxygen ion defect present in hydrothermally grown ZnO. However, the PL intensity gradually decreases with the increase of the thickness of ZnS shell, indicating charge transfer between the two components of the ZnO/ZnS hybrids. Further investigation has revealed that the hybrid nanostructures possess significantly higher visible light photocatalytic activity which is twice that of the original ZnO nanorods. The mechanisms of the optimal ZnS shell thickness to reach the maximum photocatalytic activity in the ZnO/ZnS core-shell hybrid are proposed and discussed. It is believed that this facile, rapid microwave-assisted strategy is scalable and its application can be extended synthesize other oxide/sulfide (MOx/MSy) core-shell nanostructures for different applications. [ABSTRACT FROM AUTHOR]

Polymorphic ZnO has been prepared by a solution method at low temperature (40–90 °C) and the product has been characterized by transmission electron microscopy, UV–vis absorption, and photoluminescence spectroscopy. It is found that the morphology and microstructure of ZnO can be tuned by varying the growth temperature and crystallization condition. The as-synthesized product exhibits narrowed band gap and strong orange luminescence at 620 nm, which may arise from the interstitial oxygen ion defect introduced into ZnO in the solution growth process. [ABSTRACT FROM AUTHOR]

Gd(OH)3 nanorods have been prepared via hydrothermal growth, and their microstructures are characterized by x-ray diffraction, high-resolution transmission electron microscopy and electron energy loss spectroscopy. The diameters of the Gd(OH)3 nanorods are 15–20 nm and the lengths are 150–250 nm. The nanorods are single crystalline with clean surfaces, and they grow preferentially along the [001] direction. [ABSTRACT FROM AUTHOR]

The electrical transport properties of individual carbon nanotubes (CNTs) and multi-terminal junctions of CNTs are investigated with a quadraprobe scanning tunneling microscope. The CNTs used in this study are made of stacked herringbone-type conical graphite sheets with a cone angle of [?]20° to the tube axis, and the CNT junctions have no catalytic particles in the junction areas. The CNTs have a significantly higher resistivity than conventional CNTs with concentric walls. The straight CNTs display linear current-voltage (I-V) characteristics, indicating diffusive transport rather than ballistic transport. The structural deformation in CNTs with bends substantially increases the resistivity in comparison with that for the straight segments on the same CNTs, and the I-V curve departs slightly from linearity in curved segments. The junction area of the CNT junctions behaves like an ohmic-type scattering center with linear I-V characteristics. In addition, a gating effect has not been observed, in contrast to the case for conventional multi-walled CNT junctions. These unusual transport properties can be attributed to the enhanced inter-layer interaction in the herringbone-type CNTs. [ABSTRACT FROM AUTHOR]

A sandwich-structured nanosulfur@polyaniline/graphene (nanoS@PANI/G) composite was synthesized through a facile method: polyaniline is polymerized in-situ on graphene sheets and sulfur nanoparticles are deposited into polyaniline layer simultaneously. Such a hierarchical framework combines multiple advantageous features, including a continuous electrically conducting polyaniline@graphene network binding with sulfur nanoparticles, high flexibility accommodating volume expansion and porous space for adsorbing the polysulfides. The resulting composite delivers a high initial capacity of 1625 mA h g-1, remaining a reversible capacity of ~600 mA h g-1 after 100 cycles, making it a promising cathode material for rechargeable lithium batteries with high energy density. [ABSTRACT FROM AUTHOR]

Hierarchical ZnO hollow microspheres were prepared via a carbon microspheres-templated approach, and their microstructures were analyzed by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The as-prepared ZnO products show well-defined hollow spherical morphology with a size of 2-4 µm. The thickness of ZnO shells is around 100 nm, and they are assembled by numerous nanoparticles of 30-50 nm. The optical properties of the ZnO hollow microspheres were studied, and they exhibit a narrowed band gap (2.96 eV) and a sharp violet emission at 434 nm. Moreover, the ZnO hollow microspheres show a stable and greatly enhanced photocurrent response to visible light, which can be attributed to the hierarchical structures and the narrowed band gap resulted from the carbothermic process. [ABSTRACT FROM AUTHOR]