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The human health risk of arsenic is usually evaluated based on the total amount of arsenic, however this may result in the overestimation of the hazardous effects of arsenic on human health. In this paper, the extraction methods of arsenic speciation and the in vitro gastrointestinal simulation methods of bioaccessibility of arsenic were systematically analyzed, and arsenic transformation and arsenic bioaccessibility after entering human gastrointestinal tract were discussed. The study will provide scientific basis for more accurate arsenic health risk assessment. [ABSTRACT FROM AUTHOR]

BACKGROUND: Electroporation of dorsal root ganglion is a high-efficiency gene transfection method to study nerve regeneration. In the past, the voltage condition of dorsal root ganglion electroporation resulted in a reduction in the number of labeled neurons and axons, with a high statistical error. OBJECTIVE: To improve the marker rate of neurons and their axons, and to provide theoretical basis for the study of peripheral nerve regeneration. METHODS: The enhanced green fluorescent protein was as an outcome measure to optimize dorsal root ganglion electroporation in axonal regeneration. ICR mice were randomly divided into two groups, respectively, and underwent dorsal root ganglion electroperforation surgery to detect the labeling rates of neurons and their axons under the intervention of 35 and 60 V voltages. RESULTS AND CONCLUSION: Voltages at 35 and 60 V did not cause significant neuronal death. Compared with 35 V voltage, 60 V voltage significantly increased the labeling rate of neurons and their axons as well as the number of axons passing through the injured site (P < 0.05). The 60 V voltage did not damage the behavioral function of the experimental animals. These results suggest that 60 V voltage can increase the labeling rate of neurons and their axons, providing a basis for the study of axonal regeneration in peripheral nerves. [ABSTRACT FROM AUTHOR]

Bacillus atrophaeus GQJK17 was isolated from the rhizosphere of Lycium barbarum L. in China, which was shown to be a plant growth-promoting rhizobacterium as a new biological agent against pathogenic fungi and gram-positive bacteria. We present its biological characteristics and complete genome sequence, which contains a 4,325,818 bp circular chromosome with 4,181 coding DNA sequences and a G+C content of 43.3%. A genome analysis revealed a total of 8 candidate gene clusters for producing antimicrobial secondary metabolites, including surfactin, bacillaene, fengycin, and bacillibactin. Some other antimicrobial and plant growth-promoting genes were also discovered. Our results provide insights into the genetic and biological basis of B. atrophaeus strains as a biocontrol agent for application in agriculture. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bi 2 O 2 CO 3 production via dynamic ion exchange reaction between BiOX and electrolyte. • Promoting formate production by engineering BiOI-derived Bi 2 O 2 CO 3 intermediate. • Large interlayer spacing of BiOI-derived Bi 2 O 2 CO 3 facilitating HCO 3 – diffusion. • BiOI-derived Bi 2 O 2 CO 3 improving resistance of Bi-O structures to electroreduction. Prompt production of bismuth subcarbonate (Bi 2 O 2 CO 3) intermediate is crucial for high-efficiency formate production and preservation of the bismuth-oxygen (Bi-O) structures during electrochemical CO 2 reduction reaction (CO 2 RR) catalyzed by Bi-based catalyst. In this work, we investigate the CO 2 RR performance of bismuth oxyhalide (BiOX, including BiOCl, BiOBr and BiOI) catalysts with nanosheet-assembling microsphere morphology and develop an effective strategy of engineering BiOI-derived Bi 2 O 2 CO 3 through dynamic ion exchange reaction to promote formate production from CO 2 RR. Among investigated BiOX catalysts with nanosheet-assembling microsphere morphology, BiOI exhibits the highest ion exchange rate due to the large interlayer spacing and low binding energy between [Bi 2 O 2 ]2+ layer and I− ion. The produced BiOI-derived Bi 2 O 2 CO 3 inherits the large interlayer spacing of BiOI and thus facilitates diffusion of HCO 3 – ions to promote CO 2 RR for formate production. By comparison with BiOCl and BiOBr, BiOI exhibits better CO 2 RR performance, achieving faradaic efficiency of 98 % with a current density of 42.0 mA cm−2 and excellent long-term durability. Mechanism studies demonstrate that the sufficient supply of HCO 3 – ions resulted from large interlayer spacing of BiOI-derived Bi 2 O 2 CO 3 significantly promotes formate production and, in turn, improves the resistance of Bi-O structures to electroreduction. This work provides a deep insight into the mechanism of BiOX-catalyzed CO 2 RR for formate production, opening up new opportunities for developing high-performance CO 2 RR catalysts. [ABSTRACT FROM AUTHOR]

Pancreatic β-cell dysfunction has been demonstrated to mediate key roles in the pathogenesis of gestational diabetes mellitus (GDM). Accumulating evidence has supported the functional involvement of microRNAs (miRNAs) in various types of diabetes, including GDM. However, the detailed biological effect of miRNAs in pancreatic β-cell dysfunction remains poorly understood. In the present study, microarray data of miRNAs in the blood plasma of patients with GDM were retrieved from the Gene Expression Omnibus dataset under the accession number GSE98043. Reverse transcription-quantitative PCR (RT-qPCR) was performed to measure the expression levels of miR-143-3p in the blood plasma isolated from 30 female patients with GDM women and 30 healthy female individuals. Subsequently, murine pancreatic β-cell line, MIN6 cells were treated with high glucose (HG) to construct in vitro cell models of GDM. miR-143-3p in HG-treated MIN6 cells was overexpressed or knocked down using miR-143-3p mimics and miR-143-3p inhibitor. Cell viability, insulin secretion and proinflammatory cytokine production were examined using CCK-8 and ELISA, respectively Cell apoptosis was measured by flow cytometry assay. The protein expression levels of proteins involved in the TAK1/NF-κB pathway were also assessed using western blot. The levels of miR-143-3p were found to be markedly lower in samples from patients with GDM, which were in turn negatively correlated with blood glucose levels. Overexpression of miR-143-3p in MIN6 cells significantly reversed HG-induced cell apoptosis and impairments in cell viability and insulin secretion. In addition, miR-143-3p overexpression attenuated HG-induced proinflammatory cytokine production by MIN6 cells. Subsequently, TGFβ-activated kinase 1 (TAK1), an upstream regulator of the NF-κB pathway, was found to be a direct target of miR-143-3p in pancreatic β cells through luciferase assays and western blot. Overexpression of TAK1 was revealed to abolish the curative effects of miR-143-3p on insulin secretion, cell viability and inflammatory response in HG-treated MIN6 cells. In addition, miR-143-3p could inactivate the NF-κB pathway by inhibiting TAK1 expression. Collectively, these results suggest that miR-143-3p levels are downregulated in the peripheral blood of patients with GDM. Therefore, miR-143-3p overexpression may serve as a method for preventing pancreatic β cell dysfunction by inhibiting the TAK1/NF-κB pathway. [ABSTRACT FROM AUTHOR]

Repair of large complex ventral wall hernias is challenging and outcomes are often poor due to hernia recurrence and compromised abdominal wall function. Currently, biological grafts are used to assist in repairing these complex hernias. Dermis grafts are often chosen because of their mechanical characteristics; however, dermis does not have the ability to promote the muscle regeneration needed to regain abdominal wall function. In contrast, small intestinal submucosa (SIS) grafts have been shown to promote muscle generation in volumetric muscle loss (VML) models. Hence, the objective of this study is to investigate the extent to which SIS grafts can be used together with dermis grafts to repair and promote muscle regeneration in a full-thickness abdominal wall defect in a rat model. The dermis layer is intended to mechanically bridge the defect and support constructive tissue remodeling while the SIS is intended to degrade and promote neo-muscle formation. After 16 weeks of implantation, we found only a small amount of vascularized muscle (<10% of the defect area) in the repaired defects. No significant difference in defect muscle area was found between the groups receiving the dermis + SIS scaffolds and the control (dermis alone) group. Our findings indicate that the SIS constructions investigated could not promote appreciable muscle regeneration in this rigorous animal model of VML and incomplete abdominal closure. Future investigation into combination scaffold, cell and molecular therapies would be warranted to address the need for functional muscle regeneration in challenging clinical conditions such as complex abdominal wall repair. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 355-364, 2015. [ABSTRACT FROM AUTHOR]

The nonlocal red bayberry sold in Cixi City were quantitatively analyzed for consecutive four years from 2010 to 2013, in order to understand their pesticide pollution. The results showed that the detectable rate of pesticide was 55.56%, and the pesticide detectable rate of samples was 59.09% in red bayberry. The exceeding standard rate of pesticides was 15.87%. In terms of safety index, the risk and safety state of all pesticides were within an acceptable range except cyhalothrin. In terms of risk coefficient, omethoate, triazophos and isocarbophos were at high-risk state, and the remaining 19 kinds of pesticides were at low-risk state. [ABSTRACT FROM AUTHOR]

• In-situ high temperature raman spectra of binary calcium silicate melts at the temperature of 1873 K have been measured. The corresponding quenched glasses have also been determined for comparison. • A set of clusters existing in binary calcium silicate glasses and melts were optimized and calculated by quantum chemistry ab initio calculations to obtain the raman scattering cross sections of characteristic vibrations of clusters. • A method for quantitatively analyze the microstructure of binary calcium silicate glasses and melts by raman spectroscopy was proposed and verified by 29Si MAS NMR. The quantitative distribution of different Q i species in binary calcium silicate glasses and their melts has been investigated by in-situ high temperature Raman spectroscopy, 29Si MAS NMR and quantum chemistry (QC) ab initio calculations. The structural units and several cluster structure models have been designed, optimized and calculated by ab initio calculations. The attribution of their vibrational modes, vibrational wavenumbers of non-bridging silicon-oxygen (Si-O nb) and Raman scattering cross sections (SCS) have then been worked out and analyzed. The functional relationship between the SCS and stress index of silicon-oxygen tetrahedron (SIT) was established for the model clusters of delicate Q i. Quantitative distributions of Q i in calcium silicate glasses and melts are finally obtained which are in good agreement with the experimental results of 29Si MAS NMR. Although the primary structure present in calcium silicate glasses and melts is the same, the relative distribution of Q i is different. On the basis of the present work, it will be helpful to predict the physicochemical properties of silicate slag. [ABSTRACT FROM AUTHOR]

• Heterovalent doping with Pr3+ enhances the photoluminescence of CsPbCl 3. • Dual near-band gap emissions are present in almost all perovskite nanocrystals. • Adding PrCl 3 fills the Cl-vacancy, but over-coordination leads to PL decrease. • Pr3+ adds donor states to CsPbCl 3 and improves its electronic properties. CsPbCl 3 perovskite nanocrystals are doped with heterovalent Pr3+ using hot-injection method. These Pr3+-doped CsPbCl 3 nanocrystals exhibit a dramatically improved absolute photoluminescence quantum yield (PLQY) compared to the undoped CsPbCl 3 , reaching 78.9 % PLQY at 9 % Pr-substitution. The crystal structure modification upon Pr3+ doping and luminescence mechanism are investigated using conventional optical spectroscopy and synchrotron X-ray spectroscopy (i.e., X-ray absorption fine structure and X-ray excited optical luminescence). Both the Pr3+ and Cl− are found contributing to the luminescence enhancement, and their individual roles in luminescence enhancement are analyzed. [ABSTRACT FROM AUTHOR]

The evolution of inorganic solid electrolytes has revolutionized the field of sustainable organic cathode materials, particularly by addressing the dissolution problems in traditional liquid electrolytes. However, current sulfide‐based all‐solid‐state lithium‐organic batteries still face challenges such as high working temperatures, high costs, and low voltages. Here, we design an all‐solid‐state lithium battery based on a cost‐effective organic cathode material phenanthrenequinone (PQ) and a halide solid electrolyte Li2ZrCl6. Thanks to the good compatibility between PQ and Li2ZrCl6, the PQ cathode achieved a high specific capacity of 248 mAh g−1 (96 % of the theoretical capacity), a high average discharge voltage of 2.74 V (vs. Li+/Li), and a good capacity retention of 95 % after 100 cycles at room temperature (25 °C). Furthermore, the interactions between the high‐voltage carbonyl PQ cathode and both sulfide and halide solid electrolytes, as well as the redox mechanism of the PQ cathode in all‐solid‐state batteries, were carefully studied by a variety of advanced characterizations. We believe such a design and the corresponding investigations into the underlying chemistry give insights for the further development of practical all‐solid‐state lithium‐organic batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] High-selectivity acetylene hydrogenation to produce ethylene is an important issue of removing acetylene impurity in ethylene for industrial polyethylene production. Developing high-efficiency catalyst with excellent ethylene selectivity and catalytic durability is desirable but still challenging. In this work, potassium doped palladium catalysts supported on zirconia with different K contents (Pd/ZrO 2 -xK) have been developed to catalyze acetylene hydrogenation, the Pd/ZrO 2 -16K exhibits impressive catalytic performance with acetylene conversion of 100 %, ethylene selectivity of 81 % and high catalytic durability. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), in situ synchrotron radiation photoionization mass spectrometry (SR-PIMS) and density functional theory (DFT) calculations reveal that K doping effectively weakens the adsorption of ethylene by regulating the electronic state of catalyst to improve ethylene selectivity and substantially lowers the barriers of hydrogen activation and transfer reactions to favor hydrogen spillover, thus conferring a remarkably improved durability on the Pd/ZrO 2 -16K catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] Highly efficient electrocatalyst for carbon dioxide reduction (CO 2 RR) is desirable for converting CO 2 into carbon-based chemicals and reducing anthropogenic carbon emission. Regulating catalyst surface to improve the affinity for CO 2 and the capability of CO 2 activation is the key to high-efficiency CO 2 RR. In this work, we develop an iron carbide catalyst encapsulated in nitrogenated carbon (SeN-Fe 3 C) with an aerophilic and electron-rich surface by inducing preferential formation of pyridinic-N species and engineering more negatively charged Fe sites. The SeN-Fe 3 C exhibits an excellent CO selectivity with a CO Faradaic efficiency (FE) of 92 % at −0.5 V (vs. RHE) and remarkably enhanced CO partial current density as compared to the N-Fe 3 C catalyst. Our results demonstrate that Se doping reduces the Fe 3 C particle size and improves the dispersion of Fe 3 C on nitrogenated carbon. More importantly, the preferential formation of pyridinic-N species induced by Se doping endows the SeN-Fe 3 C with an aerophilic surface and improves the affinity of the SeN-Fe 3 C for CO 2. Density functional theory (DFT) calculations reveal that the electron-rich surface, which is caused by pyridinic N species and much more negatively charged Fe sites, leads to a high degree of polarization and activation of CO 2 molecule, thus conferring a remarkably improved CO 2 RR activity on the SeN-Fe 3 C catalyst. [ABSTRACT FROM AUTHOR]