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Efficient non-noble metal catalysts are desirable to greatly improve the efficiency of anodic oxygen evolution and cathodic hydrogen evolution reactions. Herein, iron-nickel/carbon nanotube composites are synthesized as efficient bifunctional electrocatalysts for water splitting. The catalyst is homogeneously distributed, while the formation of iron-nickel alloy is confirmed. Because of the synergism of iron and copper and the contribution of carbon nanotubes, the Fe–Ni/CNT electrocatalyst shows excellent oxygen evolution reaction performance with the overpotential of 221 mV at 10 mA cm−2 and maintains stable at 0.48 V for 150 h. It expedites overall water splitting at 10 mA cm−2 with 1.50 V and show excellent stability at 20 mA cm−2 for 65 h, providing great potential for large-scale applications. • The FeNi/CNT are successfully fabricated by co-reduction. • The catalyst displays high activity and outstanding stability. • This confirm the synergism of Fe and Ni and the promotion of CNTs. • The exploration of carbon materials for potential electrocatalysis is stimulate. [ABSTRACT FROM AUTHOR]

Abstract: High speed attitude reference system is essential for large maneuverable flight, however, current flight attitude updating system is difficult to update attitude with both high speed and high precision performance. A high speed attitude updating algorithm (HSAU) with third-order computational accuracy is presented to increase computational efficiency firstly. And then the algorithm is simplified with the linear interpolation and Taylor series approaches. Finally, the algorithm is implemented on the FPGA with the Finite state machine and local parallel structure. Theoretic experiment shows that the presented simplified algorithm is more accurate than the fourth-order Runge-Kutta method in the high speed attitude updating process, and semi-physical simulation status shows that the new device is appropriate to supply timely and accurate attitude for large maneuverable flight. [Copyright &y& Elsevier]

Abstract: In the healthy artery, contractile vascular smooth muscle cells (VSMCs) have an elongated shape and are highly aligned but transition to a synthetic phenotype in culture, while additionally becoming well spread and randomly organized. Thus, controlling VSMC phenotype is a challenge in tissue engineering. In this study, we investigated the effects of micropatterning on contractile protein expression in VSMCs at low and high passage and in the presence of transforming growth factor beta 1 (TGFβ1). Micropatterning led to significantly decreased cell area, increased elongation, and increased alignment compared to non-patterned VSMCs independent of passage number. In the presence of serum, micropatterning led to increased smooth muscle myosin heavy chain (SM-MHC) and α-actin expression in low passage VSMCs, but had no effect on high passage VSMCs. Micropatterning was as effective as TGFβ1 in up-regulating SM-MHC at low passage; however, micropatterning limited VSMC response to TGFβ1 at both low and high passage. Investigation of TGFβ receptor 1 revealed higher expression in non-patterned VSMCs compared to patterned at high passage. Our studies demonstrate that micropatterning is an important regulator of SM-MHC expression in contractile VSMCs and that it may provide a mechanism for phenotype stabilization in the presence of growth factors. [ABSTRACT FROM AUTHOR]

Haemophilia B(HB) is a hereditary bleeding disorder caused by a deficiency of coagulation factor IX (FIX), which represents 15~20% of the hemophilia patients. Currently, replacement therapy is the dominant treatment, including on-demand (OD) and prophylaxis treatment. The objective of this study was to assess the cost effectiveness of prophylaxis treatment compared with OD treatment in HB children without inhibitors from the payer perspectives. [Extracted from the article]

Abstract: Polydimethylsiloxane (PDMS) is used extensively to study cell–substrate interactions because its mechanical properties are easily tuned in physiologically relevant ranges. However, changes in mechanical properties also modulate surface chemistry and cell response. Here, we correlate the mechanical and surface properties of PDMS to vascular smooth muscle cell (VSMC) behavior. We find that a 5-fold increase in base:crosslinker ratio leads to ∼40-fold decrease in elastic modulus but no significant differences in surface wettability. However, when polyelectrolyte multilayers are adsorbed to promote cell adhesion, wettability varies inversely with substrate stiffness. Despite these differences in hydrophobicity, the amount of adsorbed protein remains the same. In the absence of serum, there is a 39% decrease in cell attachment and a 42% decrease in spreading as the elastic modulus decreases from 1.79 to 0.05MPa. In the presence of serum or adsorbed fibronectin, the differences in attachment and spreading are diminished. This is not the case for the rate of serum-stimulated cell proliferation, which remains inversely dependent on crosslinker concentration. We conclude that for the range of crosslinker concentrations investigated, the surface properties dominate the initial cell attachment and spreading, whereas the mechanical properties influence the long-term cell growth. [Copyright &y& Elsevier]

Abstract: We report a case where an 8-mm mushroom patent ductus arteriosus occluder was used in a 59-year-old woman to resolve a renal artery–inferior vena cava fistula that occurred following a right nephrectomy performed 27 years earlier. Complete occlusion of the fistula was achieved. This case highlights the novel use of a PDA occluder and provides evidence that this may be a viable technique for the management of arteriovenous fistulas with similar vessel relationships, anatomical characteristics and occlusion demands as the fistula described in this report. [Copyright &y& Elsevier]

Increasing global demands for oils are fueling the production of diluted bitumen (DB) from Canada's oil sands region. More weathered than conventional crude (CC) oils, Alberta bitumen is often diluted with lighter petroleum oils to reduce density and viscosity to meet pipeline specifications for transportation. Being a heavy oil product that is transported in large volumes across Canada and the USA, there has been interest to compare its behavior and toxicity characteristics when spilled to those of CC. To determine the influence of environmental weathering upon DB following a freshwater spill, we conducted separate controlled spills of Cold Lake Blend DB and Mixed Sweet Blend light CC oil in a mesocosm spill-tank system at 24 °C with wave-action for 56 days. DB-contaminated waters remained acutely lethal for a period of 14 days to early life stage fathead minnows (Pimephales promelas) exposed during embryologic development, while CC was lethal for 1 day. However, concentrations of mono- and polycyclic aromatic compounds, often claimed to be principally responsible for the acute and chronic toxicity of crude oils, were consistently higher in CC water compared to DB. Elevated aromatic concentrations in CC water correlated with higher prevalences of developmental malformations, reduced heart and growth rates, and impacts on the aryl hydrocarbon receptor pathway. Organic acids were measured over the course of the studies and O 2 containing naphthenic acids were present at greater relative abundances in DB- compared to CC-contaminated water, with their attenuation correlating with reduced acute and sublethal toxicity. Furthermore, organic acid degradation products accumulated with time and likely contributed to the consistently sublethal toxicity of the weathered oils throughout the experiment. Improved characterization of the fractions including organic acids and those organic compounds found within the unresolved complex mixture of fresh and weathered crude oils is necessary to adequately understand and prepare for the risks that accidental petroleum spills pose to aquatic resources. [ABSTRACT FROM AUTHOR]

Over the last years, mesoporous silicas have gathered considerable interest especially in the field of catalysis, singled out as excellent catalytic supports owing to their intriguing textural features. Herein, the synthesis of novel nanoporous silicate materials containing copper or palladium nanoparticles, by means of co-assembly and one-pot templating pathways is described. Inclusion of metal nanoparticles within the porous network of the silicate materials is accomplished with the use of hyperbranched Polyethyleneimines (PEIs), serving both as chelating and secondary structure directing agents. The co-assembly method involves the introduction of PEI into the initial reaction mixture containing the triblock copolymer Pluronic P123 as the main template and TEOS as the silica source, whereas incorporation of metal nanoparticles is performed at a second step. In the one-pot approach, the only difference is that metal loading is carried out in a single step through the direct insertion of PEI already complexed with the desired metal, into the synthetic gel. Several parameters are investigated including solution's pH, reaction path and PEI's molecular weight. Results from TGA, XRD, N 2 porosimetry, electron microprobe, SEM, TEM and UV-DR analyses, confirm that both synthetic strategies can produce nanoporous materials with advanced and tunable textural and morphological characteristics and thus widened application prospects. Among the examined synthesis parameters, PEI molecular weight and synthetic gel's pH were found to have the most pronounced effect on final material pore architecture, morphology, metal loading and dispersion. Preliminary deNO x activity tests in the NO + CO reaction indicated that the developed materials could find use in environmental applications. [ABSTRACT FROM AUTHOR]

A novel templating strategy for the development of composite nanoporous CuO/CeO 2 /SiO 2 materials with advanced properties and significant thermal stability is proposed in this work, for potential use in automotive catalysts. The synthetic process is based on the dual role of low cost hyperbranched polyethyleneimine (PEI) acting both as a reactive template to control the formation of a siliceous porous network and as a metal chelating agent to facilitate the incorporation of finely dispersed CuO/CeO 2 nanoparticles into the silica matrix. Direct Ce(III)/Cu(II) introduction into the reaction mixture or post-synthetic impregnation of a preformed hybrid organic/inorganic xerogel was employed. Materials properties were assessed by means of XRD, SEM, TEM, N 2 adsorption, TPR and XPS techniques. Final Cu loading was determined by a novel UV–Vis spectroscopic method. Activity tests were performed under stoichiometric, O 2 -deficient and O 2 -rich conditions simulating realistic exhaust environment. Catalytic performance was found to be strongly depended on the employed synthetic pathway. The CuO/CeO 2 /SiO 2 composites prepared by direct introduction, exhibited enhanced structural characteristics (BET ≈ 680 m 2 /g), high homogeneity, superior oxidation performance and notable thermal stability, with great potential for use in automotive aftertreatment systems. [ABSTRACT FROM AUTHOR]

Peroxisome proliferator-activated receptor γ (PPARγ) participates in adipocyte differentiation and maintenance, including the promotion of lipid storage in mammals. In the present study, 3 duck PPARγ small interfering RNA (siRNA) expression plasmids were constructed to investigate the effect of down-regulating the expression of PPARγ on adipogenesis and fat accumulation in ducks. The results indicate that the 3 siRNA specific for conserved regions of PPARγ can effectively inhibit expression of PPARγ. It was demonstrated that the expression of lipoprotein lipase and adipocyte fatty acid-binding protein in duck adipose tissue is repressed when the expression of PPARγ is downregulated by siRNA. At the same time, the weight of abdominal fat at 21 and 35 d of age is decreased significantly (P < 0.05) compared with the control. However, the triglyceride levels in serum and muscle are not affected when the mRNA of PPARγ is repressed. The current study indicates that the suppression of PPARγ reduces abdominal fat deposition and regulates adipogenesis in ducks. [ABSTRACT FROM AUTHOR]

Abstract: PtSn/C catalysts were prepared by the direct decoration of Pt/C with Sn through a modified poly process. XRD results showed there existed obvious in this catalyst, different from the PtSn/C prepared by co-precipitation, Sn presenting in different valence. The techniques of cyclic voltammetry, anode polarization curve and single direct ethanol fuel cell (DEFC) tests were used to evaluate and compare the electrocatalytic activities to ethanol oxidation over PtSn/C prepared by different preparation procedure and over the commercial PtRu/C catalyst. The experimental results showed that PtSn/C presents higher electrocatalytic activity than PtRu/C. The results also showed that, compared to the PtSn/C prepared by co-precipitation, PtSn/C in this investigation exhibits a similar initial activity but a lower activity along with the current density increment, probably due to its poor electronic conductivity and part coverage of platinum active sites resulting from . It was found from the GC analysis results that PtSn/C can oxidize ethanol molecules to a deeper extent than PtRu/C, leading to both a higher fuel utilization coefficient and a higher fuel cell efficiency. [Copyright &y& Elsevier]

Objective: To study whether reported, but inconsistent, associations between the FMR1 CGG repeat lengths in the intermediate, high normal, or low normal range differentiate women diagnosed with diminished ovarian reserve (DOR) from population controls and whether associations vary by race/ethnic group.Design: Case-control study.Setting: Academic and private fertility clinics.Patient(s): DOR cases (n = 129; 95 Whites, 22 Asian, 12 other) from five U.S. fertility clinics were clinically diagnosed, with regular menses and no fragile X syndrome family history. Normal fertility controls (n = 803; 386 Whites, 219 African-Americans, 102 Japanese, 96 Chinese) from the United States-based SWAN Study had one or more menstrual period in the 3 months pre-enrollment, one or more pregnancy, no history of infertility or hormone therapy, and menopause ≥46 years. Previously, the SWAN Chinese and Japanese groups had similar FMR1 CGG repeat lengths, thus they were combined.Intervention(s): None.Main Outcome Measure(s): FMR1 CGG repeat lengths.Result(s): Median CGG repeats were nearly identical by case/control group. DOR cases had fewer CGG repeats in the shorter FMR1 allele than controls among Whites, but this was not significant among Asians. White cases had fewer CGG repeats in the shorter allele than Asian cases. No significant differences were found in the high normal/intermediate range between cases and controls or by race/ethnic group within cases in the longer allele.Conclusion(s): This study refutes prior reports of an association between DOR and high normal/intermediate repeats and confirms an association between DOR and low normal repeats in Whites. [ABSTRACT FROM AUTHOR]