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Nickel–cobalt layered double hydroxide (NiCo-LDH) is a promising electrode material for supercapacitors due to its high electrochemical activity. However, it easily restacks and aggregates due to its nanosheet structure, which limits the effective utilization of redox active sites. Herein, the NiCo-LDH nanosheets derived from ZIF-67 were in situ grown on the surface of a basic copper cobalt carbonate (CoCu) urchin-like skeleton and supported by nickel foam (CoCu@NiCo-LDH). The well-designed three-dimensional (3D) hierarchical nanostructure not only effectively prevents the aggregation of NiCo-LDH nanosheets, but also provides a rapid charge transport channel, which facilitates ion diffusion and electron transport, therefore enhancing the utilization of NiCo-LDH redox active sites to a greater extent. Besides, the synergistic interactions between NiCo-LDH nanosheets and CoCu nanoneedles further enrich the redox reactions and increase the electrical conductivity and reaction kinetics of the electrode at the same time. As a result, the CoCu@NiCo-LDH electrode exhibits outstanding electrochemical performance with an ultrahigh mass loading of 14 mg cm−2, including excellent specific capacitance (18.71 F cm−2 or 1346 F g−1 at 3 mA cm−2) and distinguished rate capability of 87.3% from 3 mA cm−2 to 50 mA cm−2. When the CoCu@NiCo-LDH electrode was assembled with active carbon (AC) to form an asymmetric supercapacitor (ASC), the CoCu@NiCo-LDH//AC ASCs display outstanding energy density (1.98 mW h cm−2) and power density (97.5 mW cm−2) with excellent cycling stability (86.0% initial capacitance after 5000 cycles), and could keep an LED light bulb working for 90 min after only charging for 60 s. This work provides an effective strategy for the design and application of layered double hydroxide based pseudocapacitors. [ABSTRACT FROM AUTHOR]

The Greenlandic population, a small and historically isolated founder population comprising about 57,000 inhabitants, has experienced a dramatic increase in type 2 diabetes (T2D) prevalence during the past 25 years. Motivated by this, we performed association mapping of T2D-related quantitative traits in up to 2,575 Greenlandic individuals without known diabetes. Using array-based genotyping and exome sequencing, we discovered a nonsense p.Arg684Ter variant (in which arginine is replaced by a termination codon) in the gene TBC1D4 with an allele frequency of 17%. Here we show that homozygous carriers of this variant have markedly higher concentrations of plasma glucose (β = 3.8 mmol l(-1), P = 2.5 × 10(-35)) and serum insulin (β = 165 pmol l(-1), P = 1.5 × 10(-20)) 2 hours after an oral glucose load compared with individuals with other genotypes (both non-carriers and heterozygous carriers). Furthermore, homozygous carriers have marginally lower concentrations of fasting plasma glucose (β = -0.18 mmol l(-1), P = 1.1 × 10(-6)) and fasting serum insulin (β = -8.3 pmol l(-1), P = 0.0014), and their T2D risk is markedly increased (odds ratio (OR) = 10.3, P = 1.6 × 10(-24)). Heterozygous carriers have a moderately higher plasma glucose concentration 2 hours after an oral glucose load than non-carriers (β = 0.43 mmol l(-1), P = 5.3 × 10(-5)). Analyses of skeletal muscle biopsies showed lower messenger RNA and protein levels of the long isoform of TBC1D4, and lower muscle protein levels of the glucose transporter GLUT4, with increasing number of p.Arg684Ter alleles. These findings are concomitant with a severely decreased insulin-stimulated glucose uptake in muscle, leading to postprandial hyperglycaemia, impaired glucose tolerance and T2D. The observed effect sizes are several times larger than any previous findings in large-scale genome-wide association studies of these traits and constitute further proof of the value of conducting genetic association studies outside the traditional setting of large homogeneous populations.

Rolling process was carried out with extruded polypropylene as crystalline polymer at various rolling temperatures, and the rolling characteristics, cross-section morphologies, and tensile properties were investigated. The rolling characteristics were evaluated by springback and dimensional change. The springback increased with increasing rolling temperature. The increment of length was larger than that of width because of the influence of uniaxial drawing by rotation of the rollers. Uniform morphologies were observed at a rolling ratio of 70% and a rolling temperature of 23°C. In contrast, molecular orientation near the surface was higher compared with the inner part when rolled at 70°C. Furthermore, micro spherulitic structures were observed near the surface where recrystallization occurred because of the rising temperature on the specimen surface by friction. Therefore, different morphologies appeared near the surface and in the inner part. Tensile strength was obtained for the rolling direction when rolled at 110°C lower than at other rolling temperatures. It was likely that the molecular orientation was decreased by increasing the spring-back when rolled at high temperature. POLYM. ENG. SCI., 53:2573-2581, 2013. © 2013 Society of Plastics Engineers, INTRODUCTION It is widely known that morphologies such as crystalline structure, molecular orientation, and crystallinity influence mechanical properties. For example, the properties of polymer materials are enhanced by high molecular [...]