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To investigate the impacts of the widely used chiral herbicide fenoxaprop-ethyl (FE) on aquatic organisms, the enrichment, metabolism, acute toxicity, and oxidative stress of fenoxaprop-ethyl and its main metabolites fenoxaprop (FA), ethyl-2-(4-hydroxyphenoxy)propanoate (EHPP), 2-(4-hydroxyphenoxy)propanoic acid (HPPA), and 6-chloro-2,3-dihydrobenzoxazol-2-one (CDHB) in zebrafish were studied. The enantioselectivity of fenoxaprop-ethyl and its chiral metabolites was also determined. Fenoxaprop-ethyl quickly degraded in zebrafish by aquatic exposure. FA, HPPA, and CDHB were the main metabolites that were enriched in the zebrafish. In the metabolism experiment, the half-lives of the metabolites were 0.92-1.72 days in zebrafish. The R-enantiomers of FA and HPPA were preferentially enriched and metabolized with enantiomeric fractions (EFs) of 0.65-0.85. According to the 96-h acute toxicity, FA, HPPA, EHPP, and CDHB were less toxic to zebrafish than FE, following the order of FE > CDHB > EHPP > FA > HPPA. The S-enantiomers of FE, FA, CDHB, and EHPP were more toxic than the R-enantiomers. FE and its metabolites could significantly increase catalase (CAT) and superoxide dismutase (SOD) activity and the malondialdehyde (MDA) content in gill and liver tissues, indicating their oxidative stress, and these effects were also enantioselective. This work could supply more information for evaluating the risks of fenoxaprop-ethyl on aquatic organisms concerning their metabolites and enantiomers.

Introduction We evaluated the efficacy and safety of teneligliptin compared with placebo when added to metformin therapy in Chinese patients with type 2 diabetes inadequately controlled with metformin monotherapy. Methods This multicentre, randomized, double‐blind, placebo‐controlled, parallel‐group study enrolled type 2 diabetes patients with glycosylated haemoglobin (HbA1c) 7.0%−, In this multicenter, randomized, double‐blind, placebo‐controlled, parallel‐group study, we evaluated the efficacy and safety of teneligliptin compared with placebo when added to metformin therapy in Chinese patients with type 2 diabetes inadequately controlled with metformin monotherapy. Eligible type 2 diabetes patients receiving a stable metformin dose ≥1000 mg/day received teneligliptin 20 mg or placebo orally once daily (qd) before breakfast for 24 weeks to assess the primary efficacy end‐point (change in HbA1c from baseline to Week 24) and safety (including the incidence of adverse events). The least square mean (LSM) change from baseline (standard error [SE]) was −0.72 (0.07) for teneligliptin and −0.01 (0.07) for placebo, and the differences (LSM ± SE) between the placebo and teneligliptin groups in HbA1c and FPG were −0.71% ± 0.11% and −16.5 ± 4.7 mg/dl, with similar treatment‐emergent AE incidences in both groups, indicating that teneligliptin 20 mg qd for 24 weeks added to ongoing metformin treatment was safe and tolerable, and significantly decreased HbA1c and FPG levels compared with placebo in Chinese type 2 diabetes patients.

The realization of asymmetric hollow carbonaceous nanostructures remains a great challenge, especially when biomass is chosen as the carbon resource through hydrothermal carbonization (HTC). Herein, a simple and straightforward solvent-induced buckling strategy is demonstrated for the synthesis of asymmetric spherical and bowl-like carbonaceous nanomaterials. The formation of the bowl-like morphology was attributed to the buckling of the spherical shells induced by the dissolution of the oligomers. The bowl-like particles prepared through this solvent-driven approach demonstrated a well-controlled morphology and a uniform particle size of approximately 360 nm. The obtained nanospheres and nanobowls were loaded with CoS2 nanoparticles to act as heterogeneous catalysts for the selective hydrogenation of aromatic nitro compounds. As expected, the CoS2 /nanobowls catalyst showed good tolerance to a wide scope of reducible groups and afforded both high activity and selectivity in almost all the tested substrates.

BACKGROUND Descurainia sophia L., a problematic weed in winter wheat fields in China, has developed high resistance to tribenuron-methyl. Amino acid substitutions at sites Pro197, Asp376 and Trp574 in the target acetohydroxyacid synthase (AHAS) were primarily responsible for D. sophia resistance to tribenuron-methyl. In this study, purified subpopulations of D. sophia plants individually homozygous for a specific resistance mutation (Pro197Leu, Pro197His, Pro197Ser, Pro197Thr, Asp376Glu or Trp574Leu) in AHAS were generated, and the effects of resistance mutations on D. sophia resistance and AHAS characteristics were investigated. RESULTS All resistance mutations in this study not only caused D. sophia to evolve 152- to 811-fold resistance to tribenuron-methyl but also greatly reduced AHAS sensitivity to tribenuron-methyl and increased AHAS binding affinity for the substrate pyruvate, which was primarily responsible for D. sophia resistance. The molecular docking results indicated that these resistance mutations altered AHAS binding affinity for tribenuron-methyl by reducing the hydrogen bonds and changing hydrophobic interactions. Compared with the wild-type AHAS, these resistance mutations exhibited no significant effects on AHAS feedback inhibition by branched-chain amino acids (BCAAs) at concentrations

Aim We identified and evaluated general latitudinal trends in genetic diversity within populations of a widespread arctic–alpine plant, Dryas octopetala, to examine the applicability to this species of the dominant hypothesis that intraspecific genetic diversity is highest in the tropics and declines towards the poles. Location The circumpolar Arctic and northern temperate alpine ranges, with a focus on high altitude mountains at the species lowest latitudinal margin in the Japanese archipelago. Methods Within-population genetic diversity was assessed using genotypes determined at nine microsatellite loci (n = 489), chloroplast DNA sequences (atpB-rbcL and trnV-ndhC spacers, n = 181) and a nuclear gene sequence (LEAFY, n = 173) of 18 populations, as well as a previously published amplified fragment length polymorphism dataset for 26 populations, across the distributional range of the species. The latitudinal pattern of intra-population genetic diversity was modelled at hemispheric scale to discriminate linear latitudinal and quadratic central–marginal trends in genetic diversity. Population genetic structure was assessed by Bayesian clustering analyses. Results At hemispheric scale, we identified two interacting effects: a general latitudinal decline in genetic diversity towards the equator and a central–marginal effect, whereby genetic diversity decreases towards the margins of a species’ range. This decrease was more marked in low-latitude marginal populations than in high-latitude marginal populations. Populations at the lowest latitudes in the Japanese archipelago showed the lowest level of genetic diversity but exhibited distinctive genetic variation. Main conclusion The latitudinal decline in genetic diversity within populations of this arctic–alpine plant across its range was opposite to the commonly observed trend. A significant part of the equator-ward latitudinal decline in genetic diversity in this arctic–alpine species may be attributable to a “sky island” effect, which played a greater role at low latitudes.

Purpose To validate a chemical shift-encoded (CSE) water-fat imaging for quantifying marrow fat fraction (FF), using proton magnetic resonance spectroscopy (MRS) as reference. Materials and methods Multiecho T2 -corrected MRS and CSE imaging with eight-echo gradient-echo acquisitions at 3T were performed to calculate marrow FF in 83 subjects, including 41 with normal bone mineral density (BMD), 26 with osteopenia, and 16 with osteoporosis (based on DXA). Eight participants were scanned three times with repositioning to assess the repeatability of CSE FF map measurements. Pearson correlation coefficient, Bland-Altman 95% limit of agreement, and Lin's concordance correlation coefficient were calculated. Results The Pearson correlation coefficient was 0.979 and Lin's concordance correlation coefficient was 0.962 between CSE-based FF and MRS-based FF. All data points, calculated using the Bland-Altman method, were within the limits of agreement. The intra- and interrater agreement for average CSE-based FF was excellent (intrarater, intraclass correlation coefficient [ICC] = 0.993; interrater, ICC = 0.976-0.982 for different BMD groups). In the subgroups of varying BMD, inverse correlations were observed to be very similar between BMD (r = -0.560 to -0.710), T-score (r = -0.526 to -0.747), and CSE-based FF, and between BMD (r = -0.539 to -0.706), T-score (r = -0.501 to -0.742), and MRS-based FF even controlling for age, years since menopause, and body mass index. The repeatability for CSE FF map measurements expressed as absolute precision error was 1.45%. Conclusion CSE imaging is equally accurate in characterizing marrow fat content as MRS. Given its excellent correlation and concordance with MRS, the CSE sequence could be used as a potential replacement technique for marrow fat quantification. Level of evidence 1 J. Magn. Reson. Imaging 2017;45:66-73.

Background The aim of the present study was to evaluate the efficacy and safety of polyethylene glycol loxenatide (PEX168) injections in Chinese type 2 diabetic (T2D) patients. Methods The present multicenter randomized double-blind parallel placebo-controlled clinical trial enrolled patients who had been treated with a stable dose of metformin (≥1500 mg/day) for ≥12 weeks and had an HbA1c level between 7% and 11%. Subjects were randomly divided into three groups (1: 1: 1) and were treated with once weekly subcutaneous injections of either placebo or 100 or 200 μg PEX168 for 12 weeks. All subjects continued to receive metformin daily. Results After 12 weeks treatment, the adjusted least-squares mean of HbA1c reductions from baseline values in the 100 and 200 μg PEX168 groups were significantly higher than in the placebo group (-1.02% [95% confidence interval {CI} -1.33, -0.71), -1.36% [95% CI -1.68, -1.04], and 0.13% [95% CI -0.20, 0.45], respectively; P Conclusions Continuous 12 week treatment with PEX168 showed excellent safety and efficacy in T2D patients whose glucose was not well controlled with metformin alone.

The research on multiple hydrogen bonds (H-bonds) hydrogels have gradually aroused wide interest. In this paper, a multiple H-bonds-reinforced poly(acrylamide-co-2-vinyl-4,6-diamino-2-vinyl-1,3,5-triazine)/tannic acid (P(Am-co-VDT)/TA) hydrogels are prepared. The results suggest that the prepared hydrogel has two types of H-bonds crosslinking regions: A "soft" region of H-bonds between the diaminotriazine (DAT) moieties on the polymer chains and the TA pyrogallol/catechol groups, and a "hard" region of H-bonds forming by DAT moieties with itself. The hard crosslinking region exhibits significantly higher activation energy than the soft region. Such soft and hard dual physically crosslinked networks dramatically enhance the mechanical properties of P(Am-co-VDT)/TA hydrogels in a synergistic manner (tensile strength is 2.34 MPa, elongation at break is 410%). Due to the multiple hydrogen bonds, the hydrogel has good pH sensitivity and rapid response to shape memory within a few minutes. In addition, the hydrogels have the capacity of physical adsorption of the anti-inflammatory drug diclofenac sodium and other molecules with a specific spatially arranged chemical composition. These hydrogels with high mechanical strength, excellent shape memory behavior, and capacity of adsorption of anti-inflammatory drug could be attractive candidates for applications in the fields of biomedicine, tissue engineering, and medical materials.

Heat-resistant and crosslinked polymers/ceramic composites have been prepared and investigated for enhancing high-temperature dielectric properties to adapt the development of advanced electric and electronic systems. Here, a series of crosslinkable heat-resistant poly(arylene ether sulfone)s (DPAES) with large dipole units of -SO2 - are designed and synthesized as matrix, which are blended with BaTiO3 (BT) nanoparticles to fabricate crosslinked polymer composites for boosting high-temperature dielectric properties. The results show that BT/c-DPAES possess great dielectric stability at measured frequency and temperature. Meanwhile, the discharged energy density and efficiency of BT/c-DPAES composites are higher than that of BT/DPAES at high temperatures, e.g., 10 vol% BT/c-DPAES has a discharged energy density of 1.7 J cm-3 and efficiency of 73%, increasing by 42% and 128% in contrast to BT/DPAES, respectively. The enhanced high-temperature energy storage properties can be attributed to the construction of a crosslinked polymer network, reducing leakage current density of composites.

The Hongshan quartz monzonite porphyry is one of the Yanshanian intrusions in the southern part of the Yudun Arc. Detailed zircon U–Pb data of four samples yielded ages of 78.8–80.7 Ma, indicating that the Hongshan intrusion was emplaced during the late stage of Late Cretaceous. The Hongshan intrusion shows shoshonitic and high-K calc-alkaline, with A/CNK = 0.64–1.14. The rocks show an obvious fractionation between light and heavy rare-earth elements (average [La/Yb]N = 38.85), with negative Eu anomalies (Eu/Eu* = 0.60–0.87), enrichment in large-ion lithophile elements (Rb, Th, U and K) and depletion in high field-strength elements (Nb, Ta and P). Rocks have high Sr and low Y content which are characteristics of adakitic rocks, suggesting magma derivation from thickened lower crust. In order to evaluate the nature of the source region, Hf isotope data of zircons were acquired through LA-MC-ICPMS. The negative and variable eHf(t) values demonstrate that the Hongshan intrusion was derived from ancient crust, without mantle-derived components and is significantly different from the Triassic intrusions in the southern part of the Yudun Arc. The three Yanshanian intrusions in Hongshan, Relin and Tongchangou are remarkably similar in terms of geochronology, geochemistry and Hf isotopes. We therefore infer that these intrusions had the same magmatic source and we correlate the tectonics with northward subduction of Tethys underneath the Asian continent. Copyright © 2015 John Wiley & Sons, Ltd.

Changes in plant community composition may be driven partly by the traits of dominant species during succession. In degraded northern China grasslands, plant community composition has changed remarkably and previous studies have mostly focused on the effects of anthropogenic activities, ignoring the role of interspecific interactions. We hypothesized that Potentilla acaulis, a dominant plant in heavily degraded steppe landscapes, inhibits co-occurring plant species by exuding allelopathic exudates that are inhibitory to establishing seedlings. Field vegetation surveys showed that mean heights and importance values of Stipa krylovii and Leymus chinensis were significantly lower in patches dominated by P. acaulis compared with patches dominated by S. krylovii. In germination experiments, P. acaulis extracts had significant allelopathic effects on three grass species (S. krylovii, Artemisia frigida, and L. chinensis) common in northern China grasslands. Allelopathic effects were a factor of exudate source, exudate concentration, and target species. Shoot growth of L. chinensis and A. frigida, extracts showed a “low-promotion and high-inhibition” effect, wherein low levels of exudate had a growth-promoting effect, but higher concentrations had an increasingly inhibitory effect. S. krylovii was the most sensitive target species, and both its shoot and radicle growth were significantly reduced in the presence of P. acaulis. As with the other two targets, the magnitude of inhibition increased with increasing exudate concentration. Ecologically, this study suggests that allelopathy may contribute to the dominance of P. acaulis in degraded grasslands, which has important implications for recovery of other native plants in these degraded grasslands. The specific mechanism demands further investigation.

Three TPE trimers with meta or para linkage modes have been successfully synthesized. When fabricated as emissive layers in non-doped OLEDs, they all exhibit blue or deep-blue emissions with maximum current efficiency up to 4.03 cd A−1, further verifying the facile but ingenious approach by utilizing meta-linkage mode in longer conjugated systems.

Klebsiella pneumoniae is one of the most common pathogens in nosocomial infections and is becoming increasingly multidrug-resistant. However, the underlying molecular pathogenesis of this bacterium remains elusive, limiting the therapeutic options. Understanding the mechanism of its pathogenesis may facilitate the development of antibacterial therapeutics. Here, we show that Lyn, a pleiotropic Src tyrosine kinase, is involved in host defense against K. pneumoniae (Kp) by regulating phagocytosis process and simultaneously downregulating inflammatory responses. Using acute infection mouse models, we observed that lyn−/− mice were more susceptible to Kp with increased mortality and severe lung injury compared with wild-type mice. Kp infected-lyn−/− mice exhibited elevated inflammatory cytokines (IL-6 and TNF-α), and increased superoxide in the lung and other organs. In addition, the phosphorylation of p38 and NF-κB p65 subunit increased markedly in response to Kp infection in lyn−/− mice. We also demonstrated that the translocation of p65 from cytoplasm to nuclei increased in cultured murine lung epithelial cells by Lyn siRNA knockdown. Furthermore, lipid rafts clustered with activated Lyn and accumulated in the site of Kp invasion. Taken together, these findings revealed that Lyn may participate in host defense against Kp infection through the negative modulation of inflammatory cytokines.

A new protocol for the organocatalytic asymmetric Michael addition of malononitrile to α,β-unsaturated pyrazolamides is reported. The Michael reaction proceeded smoothly in the presence of a bifunctional thiourea and provided the desired adducts in moderate to excellent yields (27–99%) and good to excellent enantioselectivities (80–95% ee).

2-Amino-3-nitrile-chromenes with potential antitumor activity were constructed by a novel catalytic system. In combination with α-naphthol, quinine could effectively promote the Michael-cyclization process of malononitrile with functionalized chalcones in high yields and moderate to good enantioselectivity (up to 84% ee). It is notable that the enantioselectivity could be greatly improved when α-naphthol was employed as additive.

Core-shell fluoroacrylate copolymer latex was synthesized via semicontinuous seed emulsion polymerization, in which ethyl acrylate was utilized to prepare core, and methyl methacrylate, butyl acrylate, methacrylate acid, and hexafluorobutyl methacrylate were employed to constitute the shell. So the yielded latex particles had the soft core and hard shell. Multifunction and low viscosity of the latex had been applied as the binder of latex inks. The ζ potential showed that the latex particles had high thermodynamic stability. The latex and latex inks exhibited viscosity plateau of Newtonian fluid behaviors. Rheological tests revealed that viscous behaviors dominated in the latex and latex inks. However, there was some interaction among the latex and pigment particles. The hydrophobicity of the cast films of the latex increased with the amount of the fluoroacrylate monomer. Fluorine tended to migrate to the interface between the cast film and air. Therefore, the hydrophobicity was derived from the fluorine enrichment phenomena on the top side of the cast films. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

All information technology (IT) resources that cloud computing provide can be seen as services. As a new IT implementation, cloud computing now has a profound impact on technological change. Cloud computing can provide critical software for business management, reducing IT and maintenance costs for hardware and software effectively. It can also enable small and medium enterprises to have access to professional IT solutions with less IT investment. The cold chain logistics system based on cloud computing can be used to connect the database between cold chain logistics and external customers, so that each database connection terminal can keep track of and update the data. A cold chain logistics system based on cloud computing is designed in this paper. This system consists of six functional parts: (1) data collection; (2) data calculation; (3) data updating and transmission; (4) configuration management; (5) control strategy; and (6) business development. It brings better cooperation between cold chain logistics and their customers, realizes co-control of product sales information, accelerates the speed of cold chain logistics and maximizes the interests of all parties. Copyright © 2011 John Wiley & Sons, Ltd.

1,2,3,4-Butanetetracarboxylic acid (BTCA) was applied to crosslink amorphous regions of cotton-type rayon fibers via anhydride-mediated esterification for the purpose of a molecular-level control over macroscopic properties. Formation of intrafiber crosslinked structures of the rayon fibers was a facile and efficient method to diminish swelling degree and enhance tensile properties. Crosslinking was conducted under a series of curing temperature and various dosages of BTCA with the presence of sodium hypophosphite as the catalyst for anhydride formation. It was found that crosslinking conditions, both the curing temperature and dosage of the crosslinking agent, made notable impacts on the crosslinking behaviors of the rayon fibers. The dry and wet tensile strength of the rayon fibers were optimized for both the dosage of the crosslinking agent and the curing temperature. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011