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Infants' expressions of discrete emotions were coded during the more stressful episodes (4 through 8) of the Strange Situation at 13 and 18 months. The data showed a significant decrease in full-face expressions (more complex configurations of movements) and a significant increase in component expressions (simpler and more constrained patterns of movements). The authors interpreted this trend as a developmental change toward more regulated and less intense emotions. Consistent with this view, the aggregate index of infants' full-face negative emotion expressions, interpreted as reflecting relatively unregulated intense emotions, correlated significantly with maternal ratings of difficult temperament. The authors discuss alternative interpretations of the findings in terms of changes in reactivity/arousability and the emerging capacity for self-regulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Abstract— Defect‐free large‐area inorganic thick‐dielectric EL (TDEL) displays using Color by Blue (CBB) technology have been successfully developed. We have achieved the world's highest blue‐phosphor luminance of 900 cd/m2 for a single‐pixel device by using CBB and by optimizing the e‐beam gun configuration and the flow rate of H2S in the vacuum chamber. By analyzing the defects on panels with triple‐pattern phosphors and CBB panels, we also found that the number of defects on CBB panels can be drastically reduced compared with those on triple‐pattern panels. The defect‐free 17‐in. VGA CBB panels show better characteristics, a high peak luminance of 600 cd/m2 and a high contrast ratio of 1000:1, compared with those of triple‐pattern panels.  相似文献   
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Various types of nanometric defects such as voids and helium (He) bubbles produced by high-energy neutron irradiations are known to degrade the mechanical properties of irradiated materials. In this study, we have evaluated the obstacle strength of He bubbles to the mobility of an edge dislocation in α-iron for 2 and 4 nm bubbles with He-to-vacancy (He/V) ratios ranging from 0 to 1 at 300 and 500 K, by molecular dynamics simulation. Results showed that as the He/V ratio increases, the obstacle strength needed for the release of a dislocation from the bubble becomes stronger up to a moderate He/V ratio (0.6 and 0.4 for 2 and 4 nm bubbles, respectively, at both temperatures), and a further increase in the He/V ratio leads to weakening of the obstacle strength. For He/V = 1, the obstacle strengths are 10–30% weaker than those at moderate He/V ratios depending on the bubble size and temperature. The extent of obstacle strength was found to be correlated with the dilation caused by He bubbles depending on the bubble size, He/V ratio, and temperature.  相似文献   
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Xyloglucan is a major hemicellulosic component in plant cell walls. Phytopathogenic fungi secrete cell wall-degrading enzymes on their infection to hosts, while the nature of the cell wall-lytic enzymes of such fungi are yet to be fully understood. Verticillium dahliae is a soil-borne fungus that causes vascular wilt diseases in a variety of commercially important crops worldwide. We purified two types of xyloglucanases, XEG12A and XEG74B, from the culture of naturally isolated Verticillium dahliae strain 2148. XEG12A showed a molecular size of 23 kDa with its maximal activity at pH 7.5. XEG12A specifically hydrolyzed xyloglucan with no activity on other β-glucans. XEG74B had a molecular size of 110 kDa with its optimum pH at 6.0. XEG74B primarily hydrolyzed xyloglucan, with a slight activity on β-1,3-1,4-glucan. Analysis of hydrolytic products of xyloglucanooligasaccharide (XXXGXXXG) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) revealed that the both enzymes cleaved β-1,4-glucosidic linkage at the position of unbranched chain, while XEG74B showed a little fluctuation with the cleavage site. Both enzymes did not hydrolyzed xyloglucanoheptasaccharide (XXXG) at all. N-Terminal and internal amino acid sequencing of the enzymes revealed that XEG12A and XEG74B belonged to Glycoside Hydrolase (GH) Families 12 and 74, respectively. Based on these results we concluded that V. dahliae XEG12A and XEG74B were xyloglucan-specific endo-β-1,4-glucanases (EC 3.2.1.151).  相似文献   
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Although amorphous silica nanoparticles are widely used in the production of food products (e.g., as anticaking agents), there is little information available about their absorption and biological effects after oral exposure. Here, we examined the in vitro intestinal absorption and in vivo biological effects in mice of orally administered amorphous silica particles with diameters of 70, 300, and 1,000 nm (nSP70, mSP300, and mSP1000, respectively) and of nSP70 that had been surface-modified with carboxyl or amine groups (nSP70-C and nSP70-N, respectively). Analysis of intestinal absorption by means of the everted gut sac method combined with an inductively coupled plasma optical emission spectrometer showed that the intestinal absorption of nSP70-C was significantly greater than that of nSP70. The absorption of nSP70-N tended to be greater than that of nSP70; however, the results were not statistically significant. Our results indicate that silica nanoparticles can be absorbed through the intestine and that particle diameter and surface properties are major determinants of the degree of absorption. We also examined the biological effects of the silica particles after 28-day oral exposure in mice. Hematological, histopathological, and biochemical analyses showed no significant differences between control mice and mice treated with the silica particles, suggesting that the silica nanoparticles evaluated in this study are safe for use in food production.  相似文献   
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