The viscoplasticity theory applied to the inelastic analysis at elevated temperatures

Monotonic and cyclic loading tests on strain rate changes are conducted on — 1Mo steel at 600°C. The examination of the tensile stress-strain response suggests that the viscosity function which characterizes the rate-dependency in the viscosity theory used previously at room temperature should not only depend on the overstress but also on the strain. A new extended viscosity control function is introduced to represent such strain dependency.The material constants of this modified viscoplasticity model are determined at temperatures of 25°C to 600°C and the model is applied to deformation tests on — 1Mo steel carried out under time-varying temperature conditions and other conditions.The extended viscoplasticity theory is shown to reproduce such various experimentally observed stress-strain behavior at elevated temperatures.     

Effects of filtration through activated carbons on peroxide,thiobarbituric acid and carbonyl values of autoxidized soybean oil

Effects of filtration bleaching on peroxide value (PV), thiobarbituric acid value (TAV) and carbonyl value (CV) of autoxidized soybean oil were investigated by using twenty-three kinds of activated carbon in order to improve oil quality. From the decreases in PV, TAV and CV and from the physical and chemical properties of activated carbons, it was suggested that hydroperoxides, aldehydes and ketones were adsorbed on the acid sites distributed over the surface or within the pores of the activated carbons while the autoxidized soybean oil flowed through the packed column. The residual tocopherols in autoxidized soybean oil and treated soybean oil were determined during storage. The decrease in oxidative stability of treated soybean oil seemed to be caused by elimination ofα-,β-andγ-tocopherols.δ-Tocopherol was chemically more stable thanα-,β- andγ-tocopherols in autoxidized soybean oil.     

Apple polyphenols influence cholesterol metabolism in healthy subjects with relatively high body mass index

We performed a randomized double-blind, placebo-controlled study on moderately obese male and female subjects (71 subjects) with a body mass index ranging from 23 to 30 to evaluate the efficacy of 12-week intake of polyphenols extracted from apples and hop bract (600 mg/day). We confirmed that 12-week ingestion of polyphenol-containing capsules significantly decreased total cholesterol and LDL-cholesterol levels. The effects of the apple polyphenol-containing capsules were more marked than those of the hop bract polyphenol-containing capsules. The visceral fat area and the level of adiponectin in the group administered apple polyphenols improved in comparison with the control group. Blood and physical examinations revealed on clinical problems, and no adverse reactions were observed during the ingestion period. These results demonstrate that apple polyphenols regulate fat metabolism in healthy subjects with relatively high body mass index.     

Non-reciprocity and topology in optics: one-way road for light via surface magnon polariton

We show how non-reciprocity and topology are used to construct an optical one-way waveguide in the Voigt geometry. First, we present a traditional approach of the one-way waveguide of light using surface polaritons under a static magnetic field. Second, we explain a recent discovery of a topological approach using photonic crystals with the magneto-optical coupling. Third, we present a combination of the two approaches, toward a broadband one-way waveguide in the microwave range.     

Estimation of the maximum power temperature coefficients of PV modules at different time scales

The maximum power temperature coefficients of a-Si modules are negative in indoor measurements, whereas the performance increases with module temperature in outdoor measurements. In order to resolve the discrepancy, we investigate the temperature coefficients of a-Si modules by two different methods corresponding to two different time scales. The results are that the temperature coefficient for a shorter time scale of several hours is negative, although the temperature coefficient for a longer time scale of seasons is positive. These results suggest that the discrepancy in temperature coefficient is partially caused by the effects of thermal annealing and light soaking. Therefore, the history of module temperature and received solar irradiance would be required for the correction of the performance of a-Si modules. In addition, we reveal that the effect of solar spectrum is also a contributory factor in the discrepancy.     

Protein engineering of diphtheria-toxin-related interleukin-2 fusion toxins to increase cytotoxic potency for high-affinity IL-2-receptor-bearing target cells

We have used site-directed insertion and point mutagenesis inan attempt to increase the cytotoxic potency and receptor-bindingaffinity of the diphtheria-toxin-related interleukin-2 (IL-2)fusion toxins. Previous studies have demonstrated that boththe DAB₄₈₆-IL-Z and DAB₃₈₉-IL-2 forms of the fusion toxin consistof three functional domains: the N-tenninal fragment-A-assodatedADP-ribosyltransferase, the hydrophobk-membrane-associatingdomains, and the C-terminal receptor-binding domain of humanIL-2. By insertion mutagenesis we have increased the apparentflexibility of the polypeptide chain between the membraneassociatingdomains and the receptor-binding domain of this fusion toxin.In comparison to DAB₄₈₆-IL-2, the cytotoxic potency of the insertionmutants was increased by 17-fold for high-affinity IL-2-receptor-bearingcell lines in vitro. Moreover, competitive displacement experimentsusing [¹²⁵I]rIL-2 demonstrate that the increase in cytotoxicpotency correlates with an increase in receptor-binding affinityfor both the high and intermediate forms of the IL-2 receptor.     

Self-assembly of concentric quantum double rings

We demonstrate the self-assembled formation of concentric quantum double rings with high uniformity and excellent rotational symmetry using the droplet epitaxy technique. Varying the growth process conditions can control each ring's size. Photoluminescence spectra emitted from an individual quantum ring complex show peculiar quantized levels that are specified by the carriers' orbital trajectories.     

Spermidine-induced destabilization of ornithine decarboxylase (ODC) is mediated by accumulation of antizyme in ODC-overproducing variant cells

The mechanism of spermidine-induced destabilization of ornithine decarboxylase (ODC) was examined in newly isolated ODC-overproducing variant cells by use of an in vitro ODC degrading system. The cells accumulated ODC protein in the presence of alpha-difluoromethylornithine. Addition of spermidine to the medium accelerated degradation of ODC protein concomitantly with induction of antizyme, a regulatory protein that binds to ODC, inhibiting its activity. Both the acceleration of ODC degradation and the induction of antizyme were inhibited by cycloheximide, but not by actinomycin D. ODC was degraded rapidly in extracts from spermidine-treated cells. The rate of ODC degradation correlated with the amount of antizyme in the extracts, and the degradation activity was abolished by treatment of the extracts with anti-antizyme antibody. Thus, antizyme induced by spermidine was essential for the accelerated degradation of ODC in the cells. ODC was phosphorylated in the cells, probably at serine residue 303 in the first internal PEST region. ODC phosphorylation occurred even when its new synthesis was inhibited by cycloheximide. Antizyme accelerated the degradations of both dephosphorylated ODC and native ODC.     

Effects of solar spectrum and module temperature on outdoor performance of photovoltaic modules in round‐robin measurements in Japan

The performance of six photovoltaic (PV) modules composed of polycrystalline silicon (pc‐Si), amorphous silicon (a‐Si), and hydrogenated amorphous silicon/crystalline silicon (a‐Si:H/c‐Si) modules was investigated at eight locations in Japan from August 2007 to December 2008. In addition, solar irradiance, solar spectrum, and module temperature were simultaneously measured in these round‐robin measurements. In this study, we evaluate quantitatively the effects of module temperature and solar spectrum on the performance of the PV modules as thermal factor (TF) and spectral factor (SF), respectively. Furthermore, we investigate the variation in module performance, which is converted into module performance under standard test conditions (STC) using the TF and SF. In the case of the pc‐Si modules, the variations in performance ratio under STC (PR_STC) for these modules range from 0.056 to 0.074 through the round‐robin measurements. The TF indicates that the contribution of module temperature to the variation in performance is large, between about 15 and 20%. However, the SF suggests that the contribution of solar spectrum is quite small, less than 3%. In the case of the a‐Si modules, the contribution of module temperature is about 8%. The performance is largely influenced by solar spectrum, more than 12% at its maximum. Consequently, the variations in the corrected PR_STC of the a‐Si modules are between 0.117 and 0.141. These large variations may result from the effects of thermal annealing and light soaking. The variation in PR_STC of the a‐Si:H/c‐Si module is similar to that of the pc‐Si modules. Copyright © 2010 John Wiley & Sons, Ltd.