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11.
Wireless Personal Communications - Internet of things (IoTs) has been the smartest technology proven worldwide these days. The application products of IoTs are Mobile ad hoc network (MANET) and...  相似文献   
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Monolithic sol–gel silica composites incorporating platinum‐based chromophores and various types of gold nanoparticles (AuNPs) are prepared and polished to high optical quality. Their photophysical properties are investigated. The glass materials show well‐defined localized surface plasmon resonance (SPR) absorbance from the visible to NIR. No redshifts of the AuNP plasmon absorption peaks due to the increase in nanoparticle doping concentration are observed in the glasses, proving that no or very small SPR coupling effects occur between the AuNPs. At 600 nm excitation, but not at 532 nm, the AuNPs improve the nonlinear absorption performance of glasses codoped with 50 × 10?3 m of a Pt‐acetylide chromophore. The glasses doped with lower concentrations of AuNPs (2–5 μm average distance) and 50 × 10?3 m in chromophore, show a marked improvement in nonlinear absorption, with no or only small improvement for the more highly AuNP doped glasses. This study shows the importance of excitation wavelength and nanoparticle concentration for composite systems employing AuNPs to improve two‐photon absorption of chromophores.  相似文献   
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The effects of feeding diest containing either cholesterol (0.24% w/w) or cholestyramine (2.5% w/w) and of fasting on sterol synthesis in the liver, ileum, and lung of both male and female guinea pigs have been studied by measuring the incorporation by tissue slices of 14C-labeled acetate into total digitoninpredipitable sterols. Cholesterol feeding significantly decreased (P less than 0.05) sterol synthesis in the liver, ileum, and lung of the males and in the ileum of females. Cholestyramine feeding stimulated the rate of hepatic sterol synthesis 13-fold but did not significantly affect sterologenesis in the ileum. Sterol synthesis in the lung was significantly increased (P less than 0.05) but to a much lesser extent than in the liver. Fatty acid synthesis in the liver, ileum, and lung was not significantly affected by either cholesterol or cholestyramine feeding. In guinea pigs fasted for 24 hr, sterol synthesis was inhibited in all three tissues, the most pronounced effect occurring in the liver. Only in the lung was fatty acid synthesis significantly decreased (P less than 0.001) by fasting. Cholesterol feeding resulted in increased concentrations of cholesterol in the plasma and liver. Cholestyramine feeding reduced plasma cholesterol concentration by 81% in females and by 64% in males. However, it did not significantly change the tissue cholesterol concentrations. Fasting resulted in a significant increase (P less than 0.05) in plasma cholesterol concentration but did not effect the concentration of cholesterol in the tissues. It was concluded that in the normal guinea pig, the feedback inhibition produced by both cholesterol and also possibly by bile acids suppresses sterol synthesis in the liver to very low rates compared to those in the small intestine, where sterologenesis is not only less sensitive to the cholesterol negative feedback system than that in the liver, but also is not subject to regulation by the bile acid negative feedback system.  相似文献   
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During the period 1964-1973, a defined sample of 740 Swedish urban school children (360 girls and 380 boys) from 40 different urban areas all over the country were followed longitudinally. Height and weight were measured twice a year and age at menarche was recorded. Mean ages at peak height velocity (PHV) and peak weight velocity (PWV) were 11-91 years (SD 0-95) and 12-50 years (SD 1-08) for girls with average values of 8-30 cm/year (SD 1-32) and 7-37 kg/year (SD 1-94). Mean age at menarche was 13-05 years (SD 1-03). PHV and PWV in boys occurred on average at 14-09 years (SD 1-11) and 14-30 years (SD 1-11) with magnitudes of 9-84 cm/year (SD 1-40) and 9-07 kg/year (SD 2-04). No significant differences between socio-economic strata defined by father's occupation and family income were found either for height and weight or for ages at PHV, PWV and menarche. Girls but not boys in the lowest social group (III) had more weight for height during puberty than had girls in social groups I and II. Between the three main geographical regions of Sweden some differences were found. Boys in the South were at the ages of 17 and 18 on average heavier than boys from the rest of the country. Boys and girls in the South had PHV, PWV and menarche half a year later than children in Middle Sweden. In analysis of variance for age at PHV significant interaction terms were found for regions times urbanization. In the South and North age at PHV was earlier the higher the urbanization level, but in Middle Sweden the reverse occurred.  相似文献   
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Jejunal lamina propria plasma cells and eosinophils and intraepithelial lymphocytes were raised in coeliac children on gluten-containing diets, but only intraepithelial lymphocytes were increased in patients on gluten-free diets. In contrast, lamina propria lymphocytes were reduced in children with coeliad disease on gluten-containing diets but were normal in paitents on gluten-free diets. In children with coeliac disease who were studied serially, lamina propria plasma cells and eosinophils and intraepithelial lymphocytes increased, and lamina propria lymphocytes decreased, within three months of the reintroduction of gluten to the diet. These observations are essentially similar to those made in the adult form of the disease and suggest that more than one type of immunological reaction is involved in the pathogenesis of the jejunal lesion.  相似文献   
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An extension of the so-called committee problem is discussed in terms of the occupancy of a certain matrix whose row totals are taken as fixed, and whose cell entries are constrained to lie between zero and defined maxima. A statistic is constructed as a function of the column totals and used to test the significance of a column effect, irrespective of row differences. Two special cases when the cell maxima are constant, first within rows and second within columns, yield a covariance matrix for the column totals whose inverse may be found explicitly, and this in turn leads to a relatively simple expression for the test statistic. Applications of this generalized problem to certain health research situations are discussed, and the adequacy of a X2 approximation to the statistic's null distribution is mentioned.  相似文献   
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