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61.
A two-dimensional computer simulation method, developed by the authors using the method of finite differences, was applied to estimate the cake growth in slip casting of alumina with a triangular gypsum mold and a box-type gypsum mold with a convex bottom. The cake growth patterns, water penetration patterns, water flow rate distributions, and pressure distributions were simulated in the molds and/or cakes. The simulated cake growth patterns were in good agreement with those observed experimentally in both molds. Moreover, the cake growths could be well understood from the results of the water flow rate distributions in each case. The present method is applicable to cake growth simulation in slip casting with complicated-shape gypsum molds.  相似文献   
62.
The distribution of nano-sized silica in binary rubber blends is characterized by scanning transmission electron microscopy (STEM) tomography combined with energy dispersive X-ray spectrometry (EDX). 3D distribution of silica is visualized by STEM-EDX tomography with the tilt-series of silicon elemental maps, while the phase-separated morphologies of polyisoprene rubber (IR) and styrene-butadiene rubber (SBR) are visualized by STEM-tomography in high-angle-annular-dark field (HAADF) mode. The combination of STEM-EDX and STEM-HAADF tomography enables us to determine the distribution of silica between the two rubber phases quantitatively even with high contents of silica up to 70 phr (weight parts per hundred rubber). It is found that silica is preferentially distributed in the SBR phase, but it is also distributed in the IR phase when the IR fraction in the total rubber components is higher than 40 wt%. The preferential distribution of silica in the SBR phase improves the dispersion of the IR domains. This is the first use of this technique for a multicomponent polymer system, showing the advantage to characterize the complicated multicomponent polymer composite morphologies.  相似文献   
63.
The spinal ejaculation generator (SEG) is located in the central gray (lamina X) of the rat lumbar spinal cord and plays a pivotal role in the ejaculatory reflex. We recently reported that SEG neurons express the oxytocin receptor and are activated by oxytocin projections from the paraventricular nucleus of hypothalamus (PVH). However, it is unknown whether the SEG responds to oxytocin in vivo. In this study, we analyzed the characteristics of the brain–spinal cord neural circuit that controls male sexual function using a newly developed in vivo electrophysiological technique. Optogenetic stimulation of the PVH of rats expressing channel rhodopsin under the oxytocin receptor promoter increased the spontaneous firing of most lamina X SEG neurons. This is the first demonstration of the in vivo electrical response from the deeper (lamina X) neurons in the spinal cord. Furthermore, we succeeded in the in vivo whole-cell recordings of lamina X neurons. In vivo whole-cell recordings may reveal the features of lamina X SEG neurons, including differences in neurotransmitters and response to stimulation. Taken together, these results suggest that in vivo electrophysiological stimulation can elucidate the neurophysiological response of a variety of spinal neurons during male sexual behavior.  相似文献   
64.
Mast cells (MCs) play critical roles in Th2 immune responses, including the defense against parasitic infections and the initiation of type I allergic reactions. In addition, MCs are involved in several immune-related responses, including those in bacterial infections, autoimmune diseases, inflammatory bowel diseases, cancers, allograft rejections, and lifestyle diseases. Whereas antigen-specific IgE is a well-known activator of MCs, which express FcεRI on the cell surface, other receptors for cytokines, growth factors, pathogen-associated molecular patterns, and damage-associated molecular patterns also function as triggers of MC stimulation, resulting in the release of chemical mediators, eicosanoids, and various cytokines. In this review, we focus on the role of interleukin (IL)-10, an anti-inflammatory cytokine, in MC-mediated immune responses, in which MCs play roles not only as initiators of the immune response but also as suppressors of excessive inflammation. IL-10 exhibits diverse effects on the proliferation, differentiation, survival, and activation of MCs in vivo and in vitro. Furthermore, IL-10 derived from MCs exerts beneficial and detrimental effects on the maintenance of tissue homeostasis and in several immune-related diseases including contact hypersensitivity, auto-immune diseases, and infections. This review introduces the effects of IL-10 on various events in MCs, and the roles of MCs in IL-10-related immune responses and as a source of IL-10.  相似文献   
65.
Resting cells of Fusarium moniliforme strain MS31 produced (R)-1-phenylpropanol from propylbenzene. The components of the medium and the reaction conditions were adjusted to increase the specific activity of the hydroxylating enzyme involved. Glucose and sodium nitrate were selected as carbon and nitrogen sources, respectively. The substrate, propylbenzene, inhibited fungal growth and the activity of the enzyme. Acetoin added to the medium increased both growth and activity of the enzyme, and hydroxylation of propylbenzene increased by 1.4-fold. Maximum bioconversion of propylbenzene by resting cells of the fungus was at 25-30 degrees C and pH 7.0 with cells at concentration of 40 mg (dry) per milliliter of reaction mixture. Conversion was accelerated as soon as propylbenzene was added; slowing 2 h later. In the end, F. moniliforme strain MS31 produced (R)-1-phenylpropanol with an enantiomeric excess of 98% at the concentration of 16 mM (2.2 mg.ml(-1)).  相似文献   
66.
ABSTRACT: A correlation between moisture content (M, g water/ g dry matter) and transverse relaxation time ( T 2) of water protons in standard wheat gel samples was established by NMR. Changes in moisture distribution in Japanese noodles were estimated from T 2 of water protons obtained by NMR micro imaging using the correlation. Penetration of water from the surface to the core during boiling and homogenization of moisture content after boiling were clearly observed in the MR images and moisture profile. A local minimum of T 2 of water protons was detected in the moisture profile of noodles boiled in tap water.  相似文献   
67.
The effect of how a wind turbine generator system is operated is discussed from the viewpoint of net power extraction with wind velocity fluctuations in relation to the scale and the dynamic behavior of the system. On a wind turbine generator system consisting of a Darrieus-Savonius hybrid wind turbine, a load generator and a battery, we took up two operating methods: constant tip speed ratio operation for a stand-alone system(Scheme1) and synchronous operation by connecting a grid(Scheme2). With our simulation model, using the result of the net extracting power, we clarified that Scheme1 is more effective than Scheme2 for small-scale systems. Furthermore, in Scheme1, the appropriate rated power output of the system under each wind condition can be confirmed.  相似文献   
68.
A lignan compound, P3, having strong antioxidative activity was found to be formed in high concentration during the industrial bleaching process of unroasted sesame seed oil. P3 (named sesaminol) was identical to a minor constituent previously isolated from acetone extract of sesame seed. It was shown that sesamolin in unprocessed sesame oil is the source of seaseminol, and the formation of seasaminol was confirmed by the model experiment with corn oil to which sesamolin had been added. Sesaminol was not so greatly removed by the deodorization process that follows bleaching as was sesamol, and it was shown to be at a concentration of ca. 100 mg/100g in commercial refined unroasted seed oil. The antioxidative activity of sesaminol was foughly equal to those of sesamol and γ-tocopherol by the thiocyanate method. Therefore, it seems that the antionxidative activity of refined unroasted seed oil is mainly attributed to sesaminol.  相似文献   
69.
The evolution of the ion beam induced luminescence (IBIL) of the polyethylene terephthalate (PET) foils was studied under the irradiation of H and He ions of MeV energy. The optical and chemical changes of the samples were also examined by photo-stimulated luminescence and optical absorption measurements after the irradiation. A prominent broad emission peak of IBIL appeared at around 380 nm, and its intensity monotonically decreased during the ion irradiation. The decay curves of the emission intensity were quantitatively explained as a function of the electronic energy deposition of the incident H and He ions. On the contrary, to the decrease of the main emission peak, a growth of new peaks was observed in the wavelengths between 500 and 600 nm.  相似文献   
70.

Background  

Many clinical studies have demonstrated that early postoperative enteral nutrition (EN) improved the postroperative course. Post-pancreaticoduodenectomy (PD), patients tend to suffer from postoperative nausea, abdominal distention, and diarrhoea, causing difficulty in the introduction of EN. In this pilot study, we investigated the appropriate nutritional mode post-pancreatic surgery.  相似文献   
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