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Background: Sepsis is defined as a life‐threatening disease. Autophagy and the microbiome are increasingly connected with sepsis. The aim of this study was to investigate the protective effect of autophagy and the possible mechanisms. Methods: The septic rat model was established by cecal ligation perforation (CLP). Rapamycin (Rap), 3‐methyladenine (3‐MA), and chloroquine (CQ) were administered to interfere autophagy. Western blot (WB) was used to detect the expression of key proteins in autophagy. Hematoxylin and eosin (H&E) staining and enzyme‐linked immunosorbent assays (ELISAs) were used to identify the effect of autophagy on various organs. 16S ribosomal RNA gene sequencing was used to analyze the changes of the gut microbiota. Results: Rap significantly upregulated the expression of key autophagy proteins, and 3‐MA reduced the relative expression compared to the CLP group. The autophagic flux showed a corresponding trend. Interestingly, the autophagy inducer significantly decreased the mortality and the lipopolysaccharide (LPS) level in serum compared with the CLP group. Autophagy activation significantly improves the inflammatory response in sepsis. Histopathological sections showed that CLP destroyed the tight junctions between ileal epithelial cells, while autophagy induction reversed the damage. The sequencing results showed that autophagy activation increased the alpha diversity and alterted the composition and structure of gut microbiota. The abundance of Proteobacteria was markedly decreased in the Rap group, whereas Bacteroidetes was notably increased compared with the CLP group. Additionally, the protective effect of autophagy further changed the biomarkers in the microbial community. The top 35 functions in each sample were analyzed to obtain 18 genes including RNA synthesis, ATP binding and transport, chromosome assignment, osmotic polysaccharide transport, transcytosis, and methylation. Conclusion: Autophagy is able to improve inflammation and may directly or indirectly regulate the microbiota of septic rats. Autophagy may be an important target for future clinical interventions in the treatment of sepsis. [ABSTRACT FROM AUTHOR]

The primary catalyst for nonalcoholic fatty liver disease (NAFLD) is widely recognized as the induction of lipotoxicity in hepatocytes by an excess of fatty acids. In China, Penthorum chinense Pursh (PcP) is commonly employed as a functional food due to its known hepatoprotective properties. The present study aimed to investigate the influence of PcP extract on in vivo and in vitro models of NAFLD. We found that PcP extract can attenuate palmitic acid (PA)‐induced lipotoxicity in HepG2 cells. PA was observed to trigger pyroptosis, as indicated by the increased expression of NLRP3 and GSDMD/N, activation of Caspase‐1, and subsequent release of IL‐1β and IL‐18. However, these changes were reversed after PcP was administered. Furthermore, the application of an NLRP3 agonist inhibited the protective effects of PcP on lipotoxicity, indicating that PcP decreased lipotoxicity by inhibiting the NLRP3/Caspase‐1/GSDMD pathway. Ultimately, we established a rat model of NAFLD through the administration of a high‐fat diet (HFD), followed by the oral delivery of PcP extracts. The results demonstrated that the administration of PcP extract effectively decreased dyslipidemia and hepatic steatosis, which coincided with a decrease in hepatic pyroptosis through modulation of the NLRP3/Caspase‐1/GSDMD pathway in liver tissues. Overall, our findings provide insight into the mechanism by which PcP extracts alleviate hepatic steatosis, highlighting the potential significance of modulating the NLRP3/Caspase‐1/GSDMD pathway in the context of pyroptosis. [ABSTRACT FROM AUTHOR]

The experiment aimed to assess the uncertainty of the determination of diazepam content in fishing baits by liquid chromatography-tandem mass spectrometry. By establishing a mathematical model and analyzing uncertainties from different sources, the experiment evaluated various uncertainty components. The results showed that the relative standard uncertainty of the measurement results was 4.55%, and the relative expanded uncertainty was 9.10%. The diazepam content in the sample should be expressed as (2.3.821±2.168) µg/kg (K=2). The study indicates that the measurement uncertainty of diazepam content in fishing baits is mainly attributed to the repeated measurements of the sample, the preparation of standard solution, and the weighing of the sample. [ABSTRACT FROM AUTHOR]

Background. Idiopathic pulmonary fibrosis (IPF) is the most common idiopathic interstitial lung disease, and it carries a poor prognosis due to a lack of efficient diagnosis methods and treatments. Epithelial-mesenchymal transition (EMT) plays a key role in IPF pathogenesis. Endoplasmic reticulum (ER) stress contributes to fibrosis via EMT-mediated pathways. Mesenchymal stem cell (MSC) transplantation is a promising treatment strategy for pulmonary fibrosis and ameliorates lung fibrosis in animal models via paracrine effects. However, the specific mechanisms underlying the effect of transplanted MSCs are not known. We previously reported that MSCs attenuate endothelial injury by modulating ER stress and endothelial-to-mesenchymal transition. The present study investigated whether modulation of ER stress- and EMT-related pathways plays essential roles in MSC-mediated alleviation of IPF. Methods and Results. We constructed a A549 cell model of transforming growth factor-β1 (TGF-β1)-induced fibrosis. TGF-β1 was used to induce EMT in A549 cells, and MSC coculture decreased EMT, as indicated by increased E-cadherin levels and decreased vimentin levels. ER stress participated in TGF-β1-induced EMT in A549 cells, and MSCs inhibited the expression of XBP-1s, XBP-1u, and BiP, which was upregulated by TGF-β1. Inhibition of ER stress contributed to MSC-mediated amelioration of EMT in A549 cells, and modulation of the IRE1α-XBP1 branch of the ER stress pathway may have played an important role in this effect. MSC transplantation alleviated bleomycin (BLM)-induced pulmonary fibrosis in mice. MSC treatment decreased the expression of ER stress- and EMT-related genes and proteins, and the most obvious effect of MSC treatment was inhibition of the IRE1α/XBP1 pathway. Conclusions. The present study demonstrated that MSCs decrease EMT by modulating ER stress and that blockade of the IRE1α-XBP1 pathway may play a critical role in this effect. The current study provides novel insight for the application of MSCs for IPF treatment and elucidates the mechanism underlying the preventive effects of MSCs against pulmonary fibrosis. [ABSTRACT FROM AUTHOR]

Nobiletin (NOB) is a naturally occurring compound, commonly found in citrus peel, that shows hepatoprotective and lipid-reducing effects. However, the lipid biomarkers and the potential improvement mechanisms have not been adequately explored. Therefore, we investigated the ameliorative effect and the molecular mechanism of NOB on NAFLD induced by a high-fat diet in mice. The results showed that supplementation with NOB over 12 weeks markedly improved glucose tolerance, serum lipid profiles, inflammatory factors, hepatic steatosis, and oxidative stress. These beneficial effects were mainly related to reduced levels of potential lipid biomarkers including free fatty acids, diacylglycerols, triacylglycerols, and cholesteryl esters according to hepatic lipidomic analysis. Twenty lipids, including DGs and phosphatidylcholines, were identified as potential lipid biomarkers. Furthermore, RT-qPCR and Western blot analysis indicated that NOB inhibited the expression of lipogenesis-related factors such as SREBP-1c, SCD-1, and FAS, and upregulated the expression of lipid oxidation (PPARα) and cholesterol conversion (LXRα, CYP7A1, and CYP27A1) genes as well as antioxidation-related factors (Nucl-Nrf2, NQO1, HO-1, and GCLC), indicating that NOB intake may reduce lipid biosynthesis and increase lipid consumption to improve hepatic steatosis and oxidative stress. This study is beneficial for understanding the ameliorative effects of NOB on NAFLD. [ABSTRACT FROM AUTHOR]

Excessive free fatty acid- (FFA-) induced endothelial lipotoxicity is involved in the pathogenesis of atherosclerosis. Endoplasmic reticulum (ER) stress is mechanistically related to endothelial lipotoxicity. Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is the major oxidatively modified low-density lipoprotein (OxLDL) receptor in endothelial cells and is highly abundant in atherosclerotic lesions. Curcumin reduces the LOX-1 expression; however, the mechanism underlying this effect remains unknown. In the current study, we explored whether curcumin ameliorates palmitic acid- (PA-) induced endothelial lipotoxicity and LOX-1 upregulation by reducing ER stress in human umbilical vein endothelial cells (HUVECs). We built endothelial lipotoxicity in vitro and found that LOX-1 was upregulated after PA stimulation, during which ER stress played an important role. Next, we observed that curcumin substantially alleviated PA-induced lipotoxicity by restoring cell viability, increasing angiogenesis, and decreasing lipid deposition. Furthermore, LOX-1 upregulation in HUVECs was blocked by curcumin, possibly via ER stress suppression. Overall, our findings demonstrated that curcumin alleviates endothelial lipotoxicity and LOX-1 upregulation, and ER stress inhibition may play a critical role in this effect. [ABSTRACT FROM AUTHOR]

The effect of dual-band light absorption enhancement in a hyperbolic rectangular array (HRA) is presented. The enhanced light absorption of the HRA results from the propagating surface plasmon (PSP) resonance, and a dual-band absorption with low and flat sideband level can be realized. The impedance theory is used to evaluate the absorption properties of the HRA, and shows that the input impedances of the HRA varied abruptly around the absorption bands to meet the impedance matching. The absorption spectra of the HRA can be estimated using the effective medium theory (EMT), and its accuracy can be improved as the number of film stacks is increased. The dual-band absorptions of the HRA are very robust to the variations of the width and the number of film stack. Potential application in refractive index sensing can be achieved by utilizing the two absorption bands. [ABSTRACT FROM AUTHOR]

A new type of high-sensitive transmission gas sensor based on the coupled gratings (CGs) and the corresponding Fabry-Pérot-like (FP-like) model for evaluating the resonance peaks are presented. The estimated locations of the FP-like resonance obtained by this theoretical model are well agreed with those of the exact results. It is shown that a narrow FP-like channel with high transmissivity occurs in the opaque background of the CGs, and its location is shifted linearly with the variation of the refractive index (RI) of the gaseous analyte. The transmission peak of the sideband can be selected as a reference, and it remains nearly fixed as the RI of the analyte is varied. Good sensing properties of the CGs sensor can be maintained, regardless of whether the two grating membranes are laterally aligned or not. The sensitivity of the CGs sensor is immune to the variation of the RI of the substrate. By selecting the higher order FP-like mode (m = 4), sensitivity as high as 748 nm/RIU with the figure of merit of 374 can be achieved. [ABSTRACT FROM AUTHOR]

Bombyx mori nuclear polyhedrosis virus (BmNPV) is an important pathogen of silkworms. Despite extensive studies in recent decades, the interaction between BmNPV and host cells is still not clearly understood. Autophagy is an intrinsic innate immune mechanism and it controls infection autonomously in virus-infected cells. In this study, we found that BmNPV infection could trigger autophagy, as demonstrated by the formation of autophagosomes, fluorescent Autophagy-related gene 8-Green Fluorescent Protein (ATG8-GFP) punctate, and lipidated ATG8. Meanwhile, autophagic flux increased significantly when monitored by the ATG8-GFP-Red Fluorescent Protein (RFP) autophagy tandem sensor and protein degradation of p62. In addition, almost all of the identified autophagy-related genes (Atgs) had been up-regulated post infection in mRNA levels. Then, we screened Atgs with the greatest fold-change during virus infection. Interestingly, all of the screened Atgs positively regulated the expression of virus genes. Further studies showed that Atg7 and Atg9 could contribute to the level of autophagy caused by viral infection. Our results demonstrated that BmNPV induced host cell autophagy to benefit its infection. These results offer insight into the complex interactions between virus and host cell, and viral pathogenesis. [ABSTRACT FROM AUTHOR]

Background: Human cytomegalovirus (CMV) has been linked to the pathogenesis of elevated arterial blood pressure (BP). Our study aimed to determine the association between anti-CMV titers and arterial BP in the Kazakh and Han Chinese populations. Material and methods: Kazakh and Han ( n = 800 each) (age, ≥18 years) subjects from Xinjiang, China were examined for anti-CMV immunoglobulin (Ig)G titers using a commercially available enzyme-linked immunosorbent assay (ELISA) kit. The highest anti-CMV titer tertiles determined within gender and ethnicity groups were compared against the two lower tertiles and seronegative samples. Results: Multivariate linear regression analysis revealed that anti-CMV titers were independent determinants for elevated systolic ( p = 0.006) BP in Kazakh women and inversely associated with systolic ( p = 0.004) and mean arterial ( p = 0.019) BP in Han women. Conclusion: The association between CMV infection and/or resulting immune response and BP elevation differed by sex and ethnicity. In Kazakh women, they were associated with elevated BP and the opposite was true among Han women. [ABSTRACT FROM AUTHOR]

Human cytomegalovirus (CMV) infection is associated with hypertension and has been linked with the pathogenesis of increased arterial blood pressure (BP). Currently, whether CMV infection is associated with the progression of hypertension and hypertensive target organ damage (TOD) remains to be identified. We aimed to examine the relationship between CMV infection and the progression of hypertension and hypertensive TOD, which could provide clues on the possible mediating mechanisms, in the Han Chinese population. A total of 372 patients with hypertension and 191 healthy controls (Han participants from Xinjiang, China) were included in the study. Enzyme-linked immunosorbent assay (ELISA) and qPCR were used to detect CMV infection. C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) titers were also analyzed using an ELISA kit. Moreover, cardiovascular disease markers were evaluated by echocardiography, carotid ultrasonography, and tomographic scans. Essential hypertension (EH) patients exhibited a marked increase in CMV IgG antibody, CRP, TNF-α, and IL-6 levels. Higher grade of hypertension and hypertensive TOD had higher CMV IgG antibody and CRP levels. The CMV IgG antibody titers were positively correlated with arterial BP, greater grade of hypertension and hypertensive TOD, and CRP and IL-6 levels. The higher quartile of CMV IgG titer and CRP level were associated with the incidence of hypertension and the progression of hypertension and hypertensive TOD. In the Han Chinese population, high CMV IgG titers are associated with the progression of hypertension and hypertensive TOD. CMV IgG titer >4.25 U could be an independent predictor of hypertension and progression of hypertension, while that >4.85 U could be an independent risk factor for hypertensive TOD. The underlying mechanism may be largely mediated by chronic inflammation. [ABSTRACT FROM AUTHOR]

Thermotolerance is important particularly for poikilotherms such as insects. Understanding the mechanisms by which insects respond to high temperatures can provide insights into their adaptation to the environment. Therefore, in this study, we performed a transcriptome analysis of two silkworm strains with significantly different resistance to heat as well as humidity; the thermo-resistant strain 7532 and the thermos-sensitive strain Knobbed. We identified in total 4,944 differentially expressed genes (DEGs) using RNA-Seq. Among these, 4,390 were annotated and 554 were novel. Gene Ontology (GO) analysis of 747 DEGs identified between RT_48h (esistant strain with high-temperature reatment for 48 hours) and ST_48h (ensitive strain with high-temperature reatment for 48 hours) showed significant enrichment of 12 GO terms including metabolic process, extracellular region and serine-type peptidase activity. Moreover, we discovered 12 DEGs that may contribute to the heat-humidity stress response in the silkworm. Our data clearly showed that 48h post-exposure may be a critical time point for silkworm to respond to high temperature and humidity. These results provide insights into the genes and biological processes involved in high temperature and humidity tolerance in the silkworm, and advance our understanding of thermal tolerance in insects. [ABSTRACT FROM AUTHOR]

DNA replication is rigorously controlled in cells to ensure that the genome duplicates exactly once per cell cycle. Geminin is a small nucleoprotein, which prevents DNA rereplication by directly binding to and inhibiting the DNA replication licensing factor, Cdt1. In this study, we have identified 2Geminingenes,BmGeminin1andBmGeminn2, in silkworm,Bombyx mori. These genes contain the Geminin conserved coiled-coil domain and are periodically localized in the nucleus during the S-G2 phase but are degraded at anaphase in mitosis. Both BmGeminin1 and BmGeminin2 are able to homodimerize and interact with BmCdt1 in cells. In addition, BmGeminin1 and BmGeminin2 can interact with each other. Overexpression ofBmGeminin1affects cell cycle progression: cell cycle is arrested in S phase, and RNA interference ofBmGeminin1leads to rereplication. In contrast, overexpression or knockdown ofBmGeminin2with RNAi did not significantly affect cell cycle, while more rereplication occurred whenBmGeminin1andBmGeminin2together were knocked down in cells than when onlyBmGeminin1was knocked down. These data suggest that both BmGeminin1 and BmGeminin2 are involved in the regulation of DNA replication. These findings provide insight into the function of Geminin and contribute to our understanding of the regulation mechanism of cell cycle in silkworm. [ABSTRACT FROM PUBLISHER]

Background: Information regarding association between cytomegalovirus (CMV) infection and essential hypertension (EH) risk is not consistent across studies. Therefore, we conducted a meta-analysis to investigate the association in detail. Methods: We comprehensively searched the published literature from the PubMed and Embase databases for any study analyzing the association between CMV and EH risk. A random-effects model was used to calculate the pooled odds ratio (OR) with 95 % confidence interval (CI). Results: Three studies involving 9657 patients were included in the meta-analysis, and the results showed a significantly increased risk of EH in patients with CMV infection. Overall, 79.3 % of the hypertension patients were CMV-positive, which was significantly higher than the percentage for controls (OR = 1.39, 95 % CI = 0.95-2.05, P = 0.017). There was significant heterogeneity among the studies included (I = 70.5 %). The funnel plot and Egger's test also indicated no publication bias. Conclusions: The results showed a significant association between CMV and EH, which indicates that CMV infection is a possible cause of EH. [ABSTRACT FROM AUTHOR]

Silk gland cells of silkworm larvae undergo multiple cycles of endomitosis for the synthesis of silk proteins during the spinning phase. In this paper, we analyzed the endomitotic DNA synthesis of silk gland cells during larval development, and found that it was a periodic fluctuation, increasing during the vigorous feeding phase and being gradually inhibited in the next molting phase. That means it might be activated by a self-regulating process after molting. The expression levels of cyclin E, cdt1 and pcna were consistent with these developmental changes. Moreover, we further examined whether these changes in endomitotic DNA synthesis resulted from feeding or hormonal stimulation. The results showed that DNA synthesis could be inhibited by starvation and re-activated by re-feeding, and therefore appears to be dependent on nutrition. DNA synthesis was suppressed by in vivo treatment with 20-hydroxyecdysone (20E). However, there was no effect on DNA synthesis by in vitro 20E treatment or by either in vivo or in vitro juvenile hormone treatment. The levels of Akt and 4E-BP phosphorylation in the silk glands were also reduced by starvation and in vivo treatment with 20E. These results indicate that the activation of endomitotic DNA synthesis during the intermolt stages is related to feeding and DNA synthesis is inhibited indirectly by 20E. [ABSTRACT FROM AUTHOR]

The proliferation of vascular smooth muscle cells (VSMCs), remodeling of the vasculature, and the renin-angiotensin system (RAS) play important roles in the development of essential hypertension (EH), which is defined as high blood pressure (BP) in which secondary causes, such as renovascular disease, are absent. The calcium-sensing receptor (CaSR) is involved in the regulation of BP. However, the underlying mechanisms by which the CaSR regulates BP are poorly understood. In the present study, the role of the CaSR in EH was investigated using male spontaneously hypertensive rats (SHRs) and rat and human plasma samples. The percentages of medial wall thickness to external diameter (WT%), total vessel wall cross-sectional area to the total area (WA%) of thoracic arteries, as well as the percentage of wall area occupied by collagen to total vessel wall area (CA%) were determined. Tissue protein expression and plasma concentrations of the CaSR, cyclic adenosine monophosphate (cAMP), renin, and angiotensin II (Ang II) were additionally assessed. WT%, WA%, and CA% were found to increase with increasing BP, whereas the plasma concentration of CaSR was found to decrease. With increasing BP, the levels of smooth muscle actin and calponin decreased, whereas those of osteopontin and proliferating cell nuclear antigen increased. The CaSR level negatively correlated with the levels of cAMP and Ang II, but positively correlated with those of renin. Our data suggest that reduced expression of the CaSR is correlated with activation of the RAS, which induces increased vascular remodeling and VSMC proliferation, and thereby associated with EH in the SHR model and in the Han Chinese population. Our findings provide new insights into the pathogenesis of EH. [ABSTRACT FROM AUTHOR]

Apoptosis is a known regulator of morphogenetic events. In mammals, the critical role of oxidative stress-induced apoptosis has been well-studied; however, in insects the role of oxidative stress in apoptosis is not clear. In a previous study, we showed that apoptosis-related genes are present in the silkworm Bombyx mori, an important lepidopteran insect model. In this study, we evaluated the effect of H2O2-induced oxidative stress on apoptosis, reactive oxygen species (ROS) levels, mitochondrial response, cytochrome c release and apoptosis-related gene expression in the BmN-SWU1 cell line from B. mori ovaries. Our results showed that BmN-SWU1 cells exposed to H2O2 showed cell protuberances, cytoplasmic condensation, apoptotic bodies, DNA ladder formation and caspase activities indicating apoptosis. H2O2-induced apoptosis also increased intracellular ROS level, changed mitochondrial distribution, reduced mitochondrial membrane potential and increased the release of cytochrome c from mitochondria. Furthermore, western blot analysis revealed a significant increase in p53 and cytochrome c expression, and a decrease in Bcl-2 expression compared to the controls. Moreover, quantitative real-time PCR (qRT-PCR) showed an increase in the transcript levels of BmICE, Bmapaf-1 and BmEndoG by 439.5%, 423.9% and 42.2%, respectively, after treatment with 1 μM H2O2 for 24 h. However, the transcript levels of Bmbuffy declined by 41.4% after 24 h of exposure to 1 μM H2O2. These results show that H2O2 treatment induced apoptosis in BmN-SWU1 cells via the mitochondrial apoptotic pathway. Further, it appears that oxidative stress induced by H2O2 activates both caspase-dependent and caspase-independent mitochondrial apoptotic pathways in silkworm cells. Taken together, these findings improve our knowledge of apoptosis in silkworm and the apoptotic pathways in insects. [ABSTRACT FROM AUTHOR]

In this paper, by using multi-temporal and high resolution Landsat data and geographic information system techniques, the land use/land cover (LULC) in the 2-km buffer zone of 52 meteorological stations in the Anhui province of China is retrieved and categorized into three types: vegetation (including farmland, forest and grass land), water (including lakes, rivers and pools), and construction (including buildings and roads). Besides, the land surface temperature (LST) in the buffer zone of these stations is also obtained from thermal infrared data. The normalized LST index (NLI) and the heat effect contribution index (HECI) of different LULC types are calculated. Via case studies and statistical analysis, the LULC and thermal environment's temporal-spatial variance in the 2-km buffer zone of these stations are surveyed, and their impacts on the observational environment are investigated. The study shows that the observational environments of the meteorological stations in Anhui province have been greatly influenced by rapid urbanization. The study proposes two new methods to classify the stations' observational environment into three types (urban, sub-urban, and rural). One uses the NLI and the other uses the HECI. The NLI method needs only LST information. The HECI method combines both LULC and LST information and, hence, is considered more reliable. The evaluation methods and criteria can be used conveniently, effectively, and quantitatively, and are especially useful when analyzing observational data from meteorological stations in weather and climate research and when choosing a location for a new meteorological station. [ABSTRACT FROM AUTHOR]

Two supramolecular compounds based on Keggin polyoxotungstates, (4,4′-H2bpy){[Cu(4,4′-bpy)]2[SiW12O40]} (1) and (4,4′-H2bpy)2[SiW12O40]·2H2O (2) have been synthesized and characterized by elemental analyses, IR, UV, XPS spectra, TG analyses, and single crystal X-ray diffraction analyses. Compound1exhibits an infinite 1-D ladder like structure, which is further interconnected into a 3-D supramolecular frameworkviahydrogen bonding interactions. Compound2contains 4,4′-bipyridine (4,4′-bpy), pseudo-Keggin polyoxoanions [SiW12O40]4−, and water molecules. Polyoxoanions together with water molecules in2construct a 3-D inorganic supramolecular network through O···O and O···Ow(1) interactions. The electrochemical behaviors and photocatalytic properties of1and2have been investigated. [ABSTRACT FROM PUBLISHER]

Four new organic–inorganic hybrid compounds, namely, [Cu3(4,4′-bpy)3][HSiW12O40]·(C3H4N2) (1), [Cu3(4,4′-bpy)3][PMo12O40]·(C5H6N2)·0.5H2O (2), [Cu2(4,4′-bpy)2][HPMo12O40]·(C5H6N2) (3) and [Cu(Phen)(4,4′-bpy)(H2O)]2[PW12O40]·(4,4′-bpy) (4) (C3H4N2 = imidazole, C5H6N2 = 2-aminopyridine, bpy = bipyridine, Phen = 1,10-phenanthroline), have been synthesized and characterized by IR, UV-vis, powder XRD, cyclic voltammetry analysis, photoluminescence analysis, elemental analyses and single crystal X-ray diffraction. The four compounds represent new examples of secondary organic moiety templated frameworks constructed from Keggin polyanions, metal ions and organic ligands. Compounds 1 and 2 present 3-D framework structures; compound 3 exhibits a 1-D ladder-like structure and compound 4 shows a 2-D layered framework structure. It is noted that the packing structures of compounds 1 and 2 are almost identical; however, the crystal space groups and cell parameters of the two are thoroughly different. Such a phenomenon has also been observed between compound 3 and a compound recently reported by us. Compound 4 is the first framework structure constructed from polyoxometalates, metal ions and mixed organic ligands. In addition, all the four frameworks are combined with dissociated organic moieties as templates. [ABSTRACT FROM AUTHOR]

Water resources are the basis of both regional sustainable development and a sustainable socioeconomy. Moreover, the evaluation of water resource security is a prerequisite for effective water resources management. Existing water resource problems have become one of the most significant factors limiting sustainable development. How to effectively identify stress factors and assess existing water resource management measures is important basis to achieve security issues. With Chongqing City of China, stress factors and the efficiency of water management measures were evaluated in this paper. The pressure, status, and response framework allows for the assessment of water resources based on three subsystems: the pressure subsystem, the status subsystem, and the response subsystem. Using an entropy-weighted set pair model, Chongqing's water resource security from 2000 to 2011 was evaluated in an effort to determine the source of the pressure on the water resources system and to evaluate the efficiency of present response measures. The results show that water resource security has generally improved in Chongqing, which was in the Moderate Warning Level from 2000 to 2006 and in the Critical Safety Level from 2007 to 2011. The pressure on the water resources system in Chongqing mainly comes from rapid economic growth, urbanization, and the development of agriculture in Three Gorges Reservoir. However, some response measures have exhausted their capacity for improvement, while the enforcement of others has not been adequate. The main reason for improvement in the water resources system in Chongqing is the increase in forest coverage and the continuous investment in ecological management of the Three Gorges Reservoir. [ABSTRACT FROM AUTHOR]

Two new compounds, [CuCl(Phen)(H2O)][PW12O40][4,4′-H2bpy]·1.5H2O (1) and [Cd2(Phen)4Cl2][HPMo12O40](4,4′-bpy) (2) (bpy = bipyridine, Phen = phenanthroline), have been hydrothermally prepared and characterized by IR, UV–vis, XPS, XRD, elemental analysis, cyclic voltammetry analysis, and single-crystal X-ray diffraction analysis. Compound1exhibits a 1-D chain structure constructed from polyoxometalates (POMs) and transition metal complexes, whereas2presents a supramolecular structure constructed from POMs, metal halide clusters, and organic ligands. [ABSTRACT FROM AUTHOR]

Two supramolecular compounds based on Keggin-type polyoxometalates (POMs), (4,4′-H2bpy)(4,4′-Hbpy)[PMo12O40] (1) and (4,4′-H2bpy)(4,4′-Hbpy)2[SiW12O40] · 4H2O (2), have been synthesized hydrothermally and characterized by elemental analyses, IR, UV-Vis, XPS spectra, thermogravimetric analyses, and single-crystal X-ray diffraction analyses. The two compounds consist of 4,4′-bipyridine (4,4′-bpy) ligands and different Keggin-type POMs which are [PMo12O40]3−for1and [SiW12O40]4−for2. There are hydrogen-bonding interactions between the POMs, 4,4′-bipyridine, and/or water in1and2. In addition,2contains an uncommon (H2O)2water cluster. [ABSTRACT FROM PUBLISHER]

Under the study of the numerical methods for SDEs, avoiding the circumscribe of Lipschitz conditions, so the strong convergence of numerical methods for SDE with markovian switching and Poisson jumps with non-Lipschitz coefficients is studied by using the properties of concave functions, and the convergence of the numerical approximation solution to the time solution with strong order p = 1/2 is showed. [ABSTRACT FROM AUTHOR]

Guizhou Province is one of the least developed areas with the largest number of counties in poverty and the widest coverage of karst landscape in China. The vulnerability of its karst eco-environment seriously threatens the survival of local residents and the development of local economy. Rapid population growth results in higher demand of various resources, which leads to more intensive development activities. For example, the blindfolded development on steep slopes has caused rock desertification of local rare soil in this karst area. It has induced a vicious circle in the poverty→population growth→ecosystem degradation and so on. About 3.13 × 106 people belong to the absolute impoverished population in Guizhou Province and most of them are living in rock-desertification areas. The essential reasons for destitution are the atrocious eco-environment and the huge population stress. Degradation of mountain ecosystems in southwestern China has continued at unprecedented speed and scale in recent decades. It is necessary to control population growth strictly and prevent further expansion of rock-desertification in order to develop local economy and better living conditions for local people. The only way to ensure a sustainable, stable and harmonious development of human, nature and economy is to restore a good condition of eco-environment and resolve the conflicts between human and land use. [ABSTRACT FROM AUTHOR]

In order to analyze the condition of special landform and regularity of special hydrological movement in karst area, the method of Geomorphologic Instantaneous Unit Hydrograph (GIUH) has been used to divide the river networks into three grades in the research area and the karst hydrologic processes were simulated with Nash instantaneous unit hydrography(NIUH). The combination of the GIUH and NIUH fully considers the moving path of water particles in drainage and the regional composition of runoff at the end of the drainage, resulting in a rational combination of probability of GIUH and NIUH and geomorphologic parameters which could reflect the complexity of the landform structure of karst drainage. The results showed that the combined method of GIUH and NIUH has clear physical concept and acceptable precision, which can be widely applied on hydrological studies of karst area. [ABSTRACT FROM AUTHOR]

A dual-band terahertz (THz) absorber using the periodic cross-shaped graphene arrays is presented. It is shown that the dual-band light absorption enhancement of graphene results from the edge graphene plasmon (EGP) resonance, and the locations of the two absorption peaks can be precisely estimated by using the Fabry-Pérot (F-P) cavity model. Slight residual reflection remains at the two absorption peaks because the input impedance of the cross-arm cannot be perfectly matched with the free space impedance. In addition, the locations of the two absorption bands can be simultaneously tuned by changing the Fermi level of graphene, and they can be independently tuned by changing the width or the length of the cross-arm of graphene. Excellent angle-insensitivity dual-band absorption enhancement of graphene can be maintained for both the transverse electric (TE) and transverse magnetic (TM) polarizations. [ABSTRACT FROM AUTHOR]

An angle-insensitive broadband absorber of graphene covering the whole visible spectrum is numerically demonstrated, which is resulted from multiple couplings of the electric and magnetic dipole resonances in the narrow metallic grooves. This is achieved by integrating the graphene sheet with a multi-grooved metasurface separated by a polymethyl methacrylate (PMMA) spacer, and an average absorption efficiency of 71.1% can be realized in the spectral range from 450 to 800 nm. The location of the absorption peak of graphene can be tuned by the groove depth, and the bandwidth of absorption can be flexibly controlled by tailoring both the number and the depth of the groove. In addition, broadband light absorption enhancement of graphene is robust to the variations of the structure parameters, and good absorption properties can be maintained even the incident angle is increased to 60°. [ABSTRACT FROM AUTHOR]