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By virtue of excellent ion storage and fast ion‐diffusion rates, molybdenum disulfide (MoS2) has been regarded as a promising electrocatalyst for hydrogen evolution reaction (HER). however, it is inherently inert to HER, its electrochemical activity is usually improved by enhancing electrical conductivity or increasing exposed active sites. To improve the conductivity and adsorption of MoS2, we prepared the MoS4‐Ppy intermediate by oxidative polymerization. Taking advantage of the adsorption properties of MoS4‐Ppy to combine with Au(III), Au(III) was simultaneously reduced to Au nanoparticles(Au NPs). Combining the Au/MoS4‐Ppy with BC and converting it into a catalyst Au/MoS2‐CNT@CNF by calcination, the catalyst activity was improved by optimizing the concentration of Au(III). Combining MoS2 with Polypyrrole (Ppy) and Bacterial cellulose (BC) not only improves the conductivity of MoS2, but also increases the exposed active sites. Notably, the obtained 50 ppm Au/MoS2‐CNT@CNFs exhibited good HER catalytic performance in an acidic electrolyte (0.5 M H2SO4) with a low overpotential of only 108 mV at a current density of 10 mA ⋅ cm−2, a low Tafel slope of 52.1 mV ⋅ dec−1, and along with outstanding stability. The improvement of electrocatalytic activity is mainly attributed to the larger electrochemical specific surface area of the composites after adsorption of Au(III) and loaded BC. The low load Au NPs can provide dense active sites. Moreover, and synergistic effect among Au NPs, MoS2, and Ppy can greatly enhance the charge transfer efficiency and lead to excellent electron transfer ability, thus significantly improving the HER performance. [ABSTRACT FROM AUTHOR]

Charge exchange reactions between Ar+(2P) and O2 (X3Σ −g) are investigated in the collision energy range of 3.40–9.24 eV within the center-of-mass coordinate, by using the ion momentum imaging technique. The internal energy of the product O2+ is enhanced gradually with the increase of collision energy, and the forward-scattered O2+ ions are distributed in the broader range of scattering angle at higher collision energies. At the low collision energy of 3.40 eV, the resonant charge transfer, similar to a photon ionization process, leads to the Franck–Condon-like vibrational state population of O2+ at the a4Πu state. At the higher collision energies, besides a4Πu and the high-lying states that are visible in the photoionization process, the O2+ products could be populated at some electronically bound states in the non-Franck–Condon region. The present observations indicate again the strong collision-energy dependences of the charge exchange reactions, but distinctly different from our previous findings for Ar+ + NO → Ar + NO+. [ABSTRACT FROM AUTHOR]

High nitrogen (N) leaching from irrigated agricultural soils is the result of N input exceeding soil N load capacity (NLC). A simple approach was developed in this research to assess the NLC of paddy soils in the southern Taihu Lake watershed. Paddy soils were classified into four types (Submergenic, Illuvium, Gleyed, and Percogenic) and 28 soil samples representing all four types were collected from across the region. The NLC values of the paddy soils were assessed using a split-line model and the spatial variability of the NLC among various rice paddy soils in the region was also evaluated with Kriging analysis. Results showed the NLC of paddy soils were both soil type and background N content related. The critical N sorption values (NLC plus soil N background) of the Gleyed, Illuvium, Submergenic, and Percogenic paddy soil samples varied from 283.1 to 315.6 mg kg-1, 203.0 to 270.2 mg kg-1, 240.6 to 254.4 mg kg-1, and 177.4 to 186.2 mg kg-1, respectively. However, on average the NLC of paddy soils in the region was 80.3 mg kg-1, and the corresponding environmental N load threshold was around 110 kg N ha-1. Geo-statistic results showed that the NLCs were unevenly distributed throughout the rice paddy dominated areas of the southern Taihu Lake watershed. The NLC assessment approach and spatial distribution information provided helpful guidance to set an environmental N threshold for best N management and hence reduce degradation of water for the whole rice ecosystem. [ABSTRACT FROM AUTHOR]

Objective To explore the risk factors of acute kidney injury (AKI) after cardiac surgery according to the acute kidney injury network (AKIN) diagnosis standard. Methods The clinical data of patients underwent cardiac surgery in first affiliated hospital of Kunming Medical College were collected retrospectively from June 2012 to June 2013, and the incidence and risk factors of AKI after cardiac surgery were statistically analyzed according to AKIN standard. Results Among 548 patients, 81 cases had AKI according the standard, with the incidence of 14.78%, and 3 patients were dead. Statistics analysis indicated that age, LVEF, hypertension, mannitol volume, CPB time, aortic cross-clamp time, cardiac arrest time, machinery ventilation time, intensive care unite stay time, preoperative UA, and preoperative serum creatinine (Scr) were significantly related to AKI after cardiac surgery. The preoperative Scr (P < 0.001), age (P < 0.001), CPB time (P < 0.001), and machinery ventilation time (P = 0.026) were independent risk factors for post-operative AKI. Conclusion AKI is the serious complication after cardiac surgery, preoperative Scr, age, CPB time and mechanical ventilation time are independent risk factors for post-operative AKI. [ABSTRACT FROM AUTHOR]

Objective To explore the criteria for early diagnosis of AKI after cardiac surgery and compare AKIN and RIFLE standard for evaluating the incidence and prognosis of AKI after cardiac surgery. Methods We retrospectively collected the data of all hospitalized patients undergoing cardiac surgery in the First Affiliated Hospital of Kunming Medical University from June 2012 to June 2013. According to AKIN and RIFLE standard, the incidence of post-operative AKI in patients was statistically analyzed. The incidence of post-operative AKI was compared between RIFLE and AKIN standard, and the AKI patients after cardiac surgery were followed. Results (1) In 548 patients with cardiac surgery, the incidence of AKI in stage I after cardiac surgery evaluated by AKIN criteria was significantly higher, while the incidence of AKI in stage II was significantly lower than that by RIFLE (P < 0.05), the incidence of AKI in stage III had no significant difference between the two criteria (P > 0.05). (2) Comparison of two diagnostic standard in the prognosis of patients with AKI showed that AKIN standard had no demonstrated advantages in evaluating the prognosis of AKI. Telephone follow-up of the AKI patients showed that 53 cases were involved in the follow-up, 28 cases were lost during follow-up period, the loss rate was 34.57%. The renal function of patients with AKI in the 1th month, the 3th month, the 6th month in the follow-up had no statistically significant difference with that at discharge from hospital. Conclusions (1) The incidence of postoperative AKI evaluated by AKIN criteria is slightly higher than that evaluated by RIFLE criteria, but the difference had no statistical significance. (2) The AKIN criteria and RIFLE criteria have no significant difference in improving AKI prognosis after cardiac surgery. (3) The renal function after hospital discharge and at discharge from hospital has no significant difference. [ABSTRACT FROM AUTHOR]

The content and speciation of heavy metals in composted sewage sludge is the main cause of negative impacts on environment and health of animal and human. An aerobic composting procedure was conducted to investigate the influences of some key parameters on phytotoxicity and speciation of Cu, Zn and Pb during sewage sludge composting. The pH value reached the optimal range for development of microorganisms, and content of organic matter (OM) and dissolved organic carbon (DOC) decreased with the composting age. The total amounts of Cu, Zn and Pb were much lower in the final compost. The results from sequential extraction procedure of heavy metals showed that composting process changed the distribution of five fractions of Cu, Zn and Pb, and reduced the total contents and sum percentages of four mobile fractions (exchangeable (EXCH), carbonate (CAR), reducible iron and manganese (FeMnOX), and organic matter bound (OMB)), indicating that the metal mobility and phytotoxicity decreased after aerobic composting. The seed germination and root growth of Pakchoi (Brassica Chinensis L.) were enhanced with composting age and reached the highest value at the end of compost. The decrease of OM and DOC was significantly correlated to changes of metal distribution and germination index (GI) of Pakchoi. Only for Cu in the compost, the GI could be predictable from the sum mobile metal fractions (EXCH+CAR+FeMnOX+OMB) (R =−0.814*). For Zn and Pb, R value was significantly increased by use of other components, such as pH, OM and DOC, which suggested that the transformation of heavy metal speciation and phytotoxicity of sewage sludge during an aerobic composting was rather strongly dependent on multiple components than a single element. [Copyright &y& Elsevier]

Stereodynamics of the collisional reaction between mutually aligned or oriented reactants has been a striking topic of chemical dynamics for decades. However, the stereodynamic aspects are scarcely revealed for the low-energy collision with a randomly oriented target. Here in the dissociative charge-exchange reaction between randomly oriented O 2 and low-energy Ar + , we, using the three-dimensional ion velocity map imaging technique, clearly observe a linear alignment and a nearly isotropic distribution of the O + yields along the collision axis. These observations are rationalized with the Doppler kinetic models in which the O 2 bond is assumed to be parallel or unparallel to the collision axis of the large impact parameter collision. The linearly aligned O + , as the predominant yield, is produced in the parallel collision, while a rotating O 2 + , as the intermediate in the unparallel collision, leads to the isotropic distribution of O + .

Ion-molecule charge-exchange reactions Ar + + CO → Ar + CO + at the center-of-mass collision energies of 4.40, 6.40, and 8.39 eV are investigated using ion velocity map imaging technique. Although multiple electronically excited states of CO + are accessed, the population of CO + at the A 2 Π state is predominant in the present collision-energy range. In contrast to our previous study for NO, but similar to the case of O 2 , the forward-scattered CO + yields show a broader angular distribution at the higher collision energy. Typically, the Franck-Condon-region charge transfer, energy resonant charge transfer, and intimate collision are three different mechanisms in which the intimate collision experiences an intermediate complex, and this mechanism usually plays an essential role in the thermal-energy reactions. However, the present observations indicate that this mechanism, concerning the intermediate (Ar-CO) + , is still of utmost importance in a relatively high collision-energy range.

Charge exchange reactions between Ar + ( 2 P) and O 2 (X 3 Σ) are investigated in the collision energy range of 3.40-9.24 eV within the center-of-mass coordinate, by using the ion momentum imaging technique. The internal energy of the product O 2 + is enhanced gradually with the increase of collision energy, and the forward-scattered O 2 + ions are distributed in the broader range of scattering angle at higher collision energies. At the low collision energy of 3.40 eV, the resonant charge transfer, similar to a photon ionization process, leads to the Franck-Condon-like vibrational state population of O 2 + at the a 4 Π u state. At the higher collision energies, besides a 4 Π u and the high-lying states that are visible in the photoionization process, the O 2 + products could be populated at some electronically bound states in the non-Franck-Condon region. The present observations indicate again the strong collision-energy dependences of the charge exchange reactions, but distinctly different from our previous findings for Ar + + NO → Ar + NO + .

Three-dimensional ion momentum imaging is developed in a combination of ion velocity map imaging technique and delay-line anode ion detection, and it is applied for the ion-molecule charge exchange reaction between Ar + and CO 2 . In a center-of-mass collision energy range of 7.23-15.96 eV, CO 2 + products are primarily populated at the ground state X 2 Π g and the single-electron excited states A 2 Π u , B 2 Σ u + , and C 2 Σ g + ; the multielectron excited states of CO 2 + are also found at the higher collision energies. The production efficiency profiles of CO 2 + are distinctly different from the photoionization electron spectrum of CO 2 , implying that the charge transfer from Ar + would be not fast as expected. The strong electron correlations in the short-lived intermediate (Ar-CO 2 ) + should be responsible for the CO 2 + yields at the multielectron excited states.

This study was purposed to characterize the genomic distribution of the binding sites for AML1-ETO fusion protein on chromosome 2, 9 and 19, and to further gain insights into the characteristics of transcriptional regulation by AML1-ETO in acute myeloid leukemia so as to provide theoretical basis for the development of targeted therapy and optimization for treatment. Chromatin immunoprecipitation (ChIP) coupled with high density tiling arrays (chip), also known as ChIP-chip, was utilized in this study. ChIP-DNA enriched by an anti-ETO antibody and total genomic DNA of Kasumi cells were hybridized to tiling arrays, tiled through chromosome 2, 9 and 19. The ChIP enriched regions were identified using a model based analytical tool (MAT). Genomic distribution of the ChIP regions was analyzed using publicly available CEAS web server. The Gene Ontology (GO) enrichment analysis was performed to excavated the biological significance. The results indicated that a total of 588 enriched regions were identified on chromosome 2, 9 and 19 by the anti-ETO antibody. A number of the identified regions were located within enhancers (48.86%) or introns (37.35%), much smaller fractions were within proximal promoters (5.96%) or exons (5.49%). Functional enrichment analysis showed that cell proliferation and signal transduction biological pathways were enriched in potential genes of AML-ETO. It is concluded that half of the AML1-ETO binding sites are located within known transcriptional regulatory regions (promoter, 5' UTR and enhancer), while almost another half were within the sequences which were not previously reported as regulatory regions. The potential target molecular network of AML1-ETO is involved in several essential biological processes.