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101.
102.
G. NiuW.W. Peng G. Saint-GironsJ. Penuelas P. RoyJ.B. Brubach J-L. Maurice G. HollingerB. Vilquin 《Thin solid films》2011,519(17):5722-5725
The work reports the direct epitaxial growth of SrTiO3 on Si (001) substrate by molecular beam epitaxy. The impact of the growth temperature and the initial oxygen partial pressure on the heteroepitaxy is studied in detail using different in-situ and ex-situ characterization methods. The optimal growth condition has been identified as 360 °C with the initial oxygen partial pressure of 5 × 10− 8 Torr to achieve a high-quality single crystalline SrTiO3 film and a coherent interface between SrTiO3 and Si. The THz Infrared (IR) measurements show that the biaxial strained SrTiO3 commensurately grown on silicon undergoes a cubic-tetragonal phase transition. 相似文献
103.
Lenguerrand E Martin JL Chiron M Lagarde E Laumon B 《Accident; analysis and prevention》2008,40(1):126-136
OBJECTIVES: To assess professional status (PS) differences in the risk of road crash involvement (RCI) (irrespective of crash severity), and to examine the underlying mechanism by evaluating the role of exposure to road risk (ERR). METHOD: A total of 15,271 subjects selected from the French GAZEL cohort were studied. A proportional hazard model for recurrent events was used to calculate the relative risks (RR) of RCI associated with PS. The associations between RCI and PS were investigated by adjusting for ERR (kilometers travelled and risk behaviors on the road). RESULTS: In all, 1890 RCI were reported. Managers have greater crude RCI risk than unskilled workers (male, RR=1.30; female, RR=1.44). This difference was no longer statistically significant when adjusting for factors describing the drivers' behaviors. Female managers' risks were also insignificant when adjusted for vehicle kilometers travelled (VKT). Managers seemed at lower risk of injury when involved in a crash. CONCLUSION: Socially advantaged subjects have the greatest RCI risk. Qualitative and quantitative ERR factors explain these disparities. These results highlight the importance to focus on ERR when studying the effect of an individual characteristic on RCI. They also highlight the importance to analyse separately the "RCI" and the "susceptibility to injury". 相似文献
104.
105.
This study investigated the effects of the type (starch vs. nonstarch) and rate of ruminal degradation of carbohydrates from the concentrate on digestion in dairy cows fed corn silage-based diets. Six ruminally cannulated cows were assigned to 6 treatments in a 6 × 6 Latin square design. Treatments were arranged in a 3 × 2 factorial design. Two starch levels [25 and 41% dry matter (DM) for low starch (LS) and high starch (HS) diets, respectively] were obtained by replacing starch-rich feedstuffs by nonstarch feedstuffs. These starch levels were combined with slowly, moderately, and rapidly rumen-degradable feedstuffs to obtain 3 levels of rapidly degradable carbohydrates from concentrate (18, 23, and 28% DM). These levels were estimated from the DM disappearance of concentrate after 4 h of in sacco incubation (CRDM). Wheat and corn grain were used as rapidly degradable and slowly degradable starch feedstuffs, respectively. Soybean hulls and citrus pulp were used as slowly degradable and rapidly degradable nonstarch feedstuffs, respectively. No interaction effect was found between dietary starch content and CRDM on pH range, volatile fatty acid (VFA) range, or VFA profile. Increasing CRDM led to a linear decrease in acetate-to-propionate ratio (from 2.7 to 2.1), and a linear increase in the pH and VFA ranges (from 0.86 to 1.12 pH units and from 34 to 56 mM, respectively). Feeding HS diets decreased acetate-to-propionate ratio (2.6 vs. 2.0) and increased pH range (0.89 vs. 1.04 pH units), but had no effect on VFA range. Increasing CRDM linearly decreased mean ruminal pH in LS diets but linearly increased mean ruminal pH in HS diets. Fibrolytic activity was unaffected in LS diets but decreased strongly in HS diets (from 62 to 50%). These findings suggest that pH regulation differs on a short-term and on a longer-term basis. In the short-term, increasing CRDM increased the rate of VFA production, which may have been partly buffered under LS diets due to the higher cation exchange capacity of nonstarch feedstuffs compared with starch-rich feedstuffs. In the longer term, feeding starch reduced fibrolytic activity, which may have led to lower total VFA production and higher mean pH. The results of this experiment clearly show that both fermentative characteristics of the concentrate and dietary starch content should be taken into account when formulating diets to prevent subacute ruminal acidosis and to predict VFA profile. 相似文献
106.
Mulhern R Fieldman G Hussey T Lévêque JL Pineau P 《International journal of cosmetic science》2003,25(4):199-205
This study sought to investigate whether cosmetics do improve female facial attractiveness, and to determine whether the contribution of different cosmetic products are separable, or whether they function synergistically to enhance female beauty. Ten volunteers were made up by a beautician under five cosmetics conditions: (i) no make-up; (ii) foundation only; (iii) eye make-up only; (iv) lip make-up only; and (v) full facial make-up. Male and female participants were asked to view the 10 sets of five photographs, and rank each set from most attractive to least attractive. As predicted, faces with full make-up were judged more attractive than the same faces with no make-up. Sex differences within the results were also apparent. Women judged eye make-up as contributing most to the attractiveness. Men rated eye make-up and foundation as having a significant impact on the attractiveness of a full facial makeover. Surprisingly, lipstick did not appear to contribute to attractiveness independently. 相似文献
107.
The barley mutant, TR49, selected in Spain for rapid germination, and its parent cultivar Troubadour, were grown in Scotland in 1991 and assessed for a range of grain and malt quality characters. Results suggested that both genotypes had a potential dormancy problem, although TR49 showed a slight but significant improvement over Troubadour. TR49 produced very large grain which did not completely modify during malting, but still showed an advantage over its parent cultivar for all malting parameters assessed. 相似文献
108.
Wang JL Ruan H Zhang HF Zhang Q Zhang HB He GQ Shen SR 《Journal of food science》2007,72(9):C452-C456
ABSTRACT: An extreme thermostable and acidic tolerable β-glucanase was isolated and characterized from aerobic fungi Trichoderma koningii ZJU-T. The optimal reaction temperature and pH for the β-glucanase were 100 °C and pH 2.0, respectively. The β-glucanase showed increased stability at higher temperatures and lower pH values when compared to other β-glucanases. The optimum conditions for the β-glucanase stability were found to be pH 4.0 and 80 °C. Even subjected to 100 °C for 3 h, β-glucanase activity did not show significant reduction. Moreover, K+ significantly enhanced β-glucanase activity at the concentration of 1 mM, while EDTA and other metal ions such as Mg2+ , Mn2+ , Zn2+ , Ca2+ , Fe2+ , Pb2+ , and Fe3+ inhibited β-glucanase activity. Denaturants, including sodium dodecyl sulfate (SDS) and mercaptoethanol, also inhibited β-glucanase activity at a concentration of 5%. However, in the presence of 7 M urea, residual activity of the β-glucanase still remained 14.5%. 相似文献