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1.
Photosynthetic microorganisms are expected to be useful to maintain an oxygenic atmosphere and to provide biomass for astronauts in the International Space Station as well as in future long-term space flights. However, fluxes of complex ionizing radiation of various intensities and energies make space an extreme environment for the microorganisms, affecting their photosynthetic efficiency. To automatically monitor the photosynthetic Photosystem II (PSII) activity of microorganisms under space conditions an optical biosensor, which utilizes chlorophyll fluorescence as biological transduction system, was built; the PSII activity was monitored by the biosensor during balloon flights at stratospheric altitudes of about 40 km. The effect of space stress on quantum yield of PSII varied among the tested species depending on the growth light conditions at which they were exposed during the flights.  相似文献   
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位于我国西北部的新疆维吾尔自治区在多民族融合交流下形成了独特的人文环境,“袷袢”作为新疆多个民族传统服装款式之一,依据其款式、色彩及装饰风格各民族袷袢特点各异。通过研究新疆地区传统民族服饰“袷袢”与不同民族间的差异性,从中了解各民族间在服饰文化中的相互交融与影响,研究“袷袢”这一典型性民族服饰在文化交融中的共性与特性,从而更准确地认知民族服饰的文化功能,及中华民族多元一体格局下的服饰文化与审美趋向。  相似文献   
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Background  

The health benefits of soy isoflavones have been widely investigated; however, there are some concerns as to whether soy isoflavones, similar to ipriflavone, a synthetic isoflavone, cause lymphocytopenia in postmenopausal women. Hence, the purpose of this study was to investigate the extent to which 12-month supplementation of 25 g soy protein containing 60 mg isoflavones alters lymphocyte counts or other hematological parameters in postmenopausal women who were not on hormone replacement therapy.  相似文献   
6.
Rubber particles from tires out of use (TOU) were used to modify an epoxy-based thermoset. The effect of size and particle content were evaluated. Three bending point and Charpy tests were carried out to study the mechanical behavior of the materials. A steady decrease in the critical stress intensity factor, KIc, with the content of TOU was observed, being attributed to the fact that the particles might also act as defects in the polymer matrix. Fractographic analysis confirmed that filled specimens showed localized shear yielding at the end of the particles along the crack propagation direction. No signs of cavitation mechanism were found on the surfaces of fracture, evidencing an extraordinary interfacial adhesion. The total energy absorbed at break increased as the size of TOU particles decreased, pointing out that particle size is crucial for the performance of these materials. Matrix yielding and plastic deformation were considered to be the main toughness mechanisms.  相似文献   
7.
In this experimental study, we investigated the effects of spandex filament drawing ratio and weave structures on the properties of cotton/spandex woven fabrics. One-way analysis of variance was used to explore the significant effects of the independent variables on the fabric properties. A regression analysis was also used to derive regression relationships between each of fabric properties and spandex filament drawing ratio. Our findings show that the spandex drawing ratio and structures of the woven fabrics significantly affect the physical and mechanical properties of the cotton/spandex woven fabrics. Cotton woven fabrics containing spandex show higher contraction, crease recovery, and flexural rigidity with increasing spandex drawing ratio, whereas the rest of fabric properties decreases with the increasing drawing ratio. Because of higher contraction and then higher weight, thickness, and cover factor of cotton/spandex fabrics, unexpected results of fabric air permeability and breaking elongation were detected.  相似文献   
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Software and Systems Modeling - In this paper, we introduce a SQL-PL code generator for OCL expressions that, in contrast to other proposals, is able to map OCL iterate and iterator expressions...  相似文献   
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Background  

Although soy protein and its isoflavones have been reported to reduce the risk of osteoporosis in peri- and post-menopausal women, most of these studies are of short duration (i.e. six months). The objective of this study was to examine if one year consumption of soy-containing foods (providing 25 g protein and 60 mg isoflavones) exerts beneficial effects on bone in postmenopausal women.  相似文献   
10.
We discuss time-dependent factorial cumulants in interacting nano-scale systems. Recent theoretical work has shown that the full counting statistics of non-interacting electrons in a two-terminal conductor is always generalized binomial and the zeros of the generating function are consequently real and negative. However, as interactions are introduced in the transport, the zeros of the generating function may become complex. This has measurable consequences: With the zeros of the generating function moving away from the real-axis, the high-order factorial cumulants of the transport become oscillatory functions of time. Here we demonstrate this phenomenon on a model of charge transport through coherently coupled quantum dots attached to voltage-biased electrodes. Without interactions, the factorial cumulants are monotonic functions of the observation time. In contrast, as interactions are introduced, the factorial cumulants oscillate strongly as functions of time. We comment on possible measurements of oscillating factorial cumulants and outline several avenues for further investigations.  相似文献   
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