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排序方式: 共有978条查询结果,搜索用时 15 毫秒
851.
Marcella Mastromatteo Alessandra Danza Lucia Lecce Sara Spinelli Vincenzo Lampignano Janine Laverse Francesco Contò Matteo Alessandro Del Nobile 《International Journal of Food Science & Technology》2014,49(1):72-81
In this study, the effect of different durum wheat varieties on the sensorial and nutritional quality of bread was assessed. In particular, bread manufactured with six wheat cultivars was compared with bread based on commercial semolina mixtures. X‐ray microtomography was used to characterise the final cellular structure of the baked bread. The textural properties of baked bread and doughs were also investigated. In addition, the glucose equivalent (GE) of bread was also evaluated. Finally, the microstructural, sensorial and textural parameters were correlated with each other. Results highlighted that Cappelli and Saragolla bread samples showed higher protein and total soluble fibre content, respectively, in comparison with the reference samples. Moreover, the GE of the Cappelli, Claudio and Saragolla bread samples was similar to that of the reference samples and lower than that of the other samples. However, the sensorial properties of all bread samples showed a very positive score (up to 7.7). 相似文献
852.
Smoking-related death and disability rates for women have risen sharply recently. Despite lower smoking cessation success rates for women using behavioral therapies, data are limited on whether specific pharmacological therapies are equally efficacious in men and women. Using meta-analytic techniques, we examined whether significant differences in therapeutic efficacy of nicotine replacement therapy (NRT) for smoking cessation exist by sex. Out of the 31 randomized clinical trials of NRT that met inclusion criteria, 11 contributed to the analysis. The odds ratios for NRT vs. placebo were derived from each trial separately by sex for males and females, and these ratios were combined to give a pooled estimate of the effect of sex in response to NRT. NRT was effective at all time points in men (< 6 months: OR = 2.05, 95% CI= 1.61-2.60; 6 months: OR = 1.98, 95% CI = 1.51-2.60; 12 months: OR = 1.86, 95% CI = 1.39-2.50) and women (< 6 months: OR = 2.09, 95% CI = 1.65-2.65; 6 months, OR = 1.52, 95% CI = 1.17-1.98; 12 months: OR = 1.63, 95% CI = 1.22-2.18). At all time points, no significant difference was observed between sexes (< 6 months: OR = .97, 95% CI = .69-1.36; 6 months: OR = 1.33, 95% CI = .91-1.95; 12 months: OR = 1.21, 95% CI = .79-1.84). The results of this meta-analysis do not support the hypothesis that NRT has higher therapeutic efficacy for men than women. 相似文献
853.
Maria Aversa Stefano Curcio Vincenza Calabrò Gabriele Iorio 《Food and Bioprocess Technology》2012,5(1):118-129
The aim of this work was to evaluate the effect of operating conditions on the quality of dried foods, monitoring shrinkage, rehydration capacity, and color changes. Carrot samples of different shapes and dimensions were dried in a convective oven by air whose temperature and velocity were chosen in a range of physical significance. Two values of air velocity, i.e., 2.8 and 2.2 m/s, were considered; air temperature was chosen equal to 50 °C, 70 °C, and 85 °C. It was observed that more drastic drying conditions indeed improved the drying rate, but were also responsible for a decrease of food rehydration capacity. Food behavior was observed comparing some characteristic parameters as obtained upon fitting the experimental data by simple modeling equations. In particular, the drying curves were fitted by the Newton’s model, whereas, shrinkage was modeled by a linear relationship between volume variation and moisture content. Rehydration capacity was estimated by water regain percentage, which was evaluated after 5 h. 相似文献
854.
David J Drobes Marcus R Munafò Fiona Leigh Michael E Saladin 《Nicotine & tobacco research》2005,7(1):41-46
Despite a growing appreciation that genetic factors may impart vulnerability toward smoking behavior, only a modest consensus has been created about the specific genetic mechanisms that may underlie various aspects of smoking. A core feature of genetic contribution toward any complex human behavior is familial resemblance. Most previous attempts to index familial smoking have classified individuals into discrete categories, based on the number of smokers in a family. We discuss the development of a continuous measure of familial smoking, the Family Smoking Index (FSI), which is based on the proportion of smokers in first- and second-degree family members and provides a more precise weighting according to genetic proximity. We present the psychometric characteristics of the FSI as well as initial validation data from two studies. We also describe current and future directions for continued FSI validation and application. 相似文献
855.
Claudia Dragonetti Stefania Righetto Dominique Roberto Adriana Valore Tiziana Benincori Francesco Sannicolò Filippo De Angelis Simona Fantacci 《Journal of Materials Science: Materials in Electronics》2009,20(Z1):460-464
The luminescence and second order non linear optical (NLO) response of [Ir(ttpy)2(5-R-1,10-phen)][PF6] (ttpy = cyclometallated 3′-(2-pyridil)-2,2′:5′,2″-terthiophene, phen = phenanthroline; R = Me, NO2) and [Ir(pq)2(5-R-1,10-phen)][PF6] (pq = cyclometallated 2-phenylquinoline) have been investigated experimentally in CH2Cl2 solution and compared with that of [Ir(ppy)2(5-R-1,10-phen)][PF6] (ppy = cyclometallated 2-phenylpyridine), characterized by one of the highest second order NLO response ever reported for a metal complex. Substitution of ppy with the more π-delocalized pq does not affect significantly the luminescence and NLO properties. A slightly lower NLO response and a much poorer luminescence is observed for the related complexes with ttpy. In these complexes, DFT/TDDFT calculations show that the presence of ttpy induces a significant downshift of the HOMO energy, compared to ppy and pq. The NLO response is dominated by intense MLCT excited states, which are also assigned as originating the emission. 相似文献
856.
G. Busatto G. Currò F. Iannuzzo A. Porzio A. Sanseverino F. Velardi 《Microelectronics Reliability》2008,48(8-9):1306-1309
The results presented in this paper are related to an experimental study that has the aim to evidence the formation of “latent gate oxide damages” in medium voltage power MOSFETs during the impact with energetic particles. The understanding of these “latent defectiveness” can be an helpful aid in the comprehension of the mechanisms of breach of the oxide layer of MOS structures induced by single energetic particles impact (single event gate rupture). To properly detect the presence of “latent damages” we have developed a high resolution experimental set-up and identified an appropriate region in which the device have to be biased in order to trigger this kind of damage. 相似文献
857.
The unsteady flow and solid transport simulation problem in artificial channels is solved using a three-equation model, coupled with a local erosion law. The three equations are the water mass and momentum balance equations, as well as the total solid load balance equation. It is shown that even during severe hydrological events inertial terms can be neglected in the momentum equation without any substantial change in the solution sought. Empirical equilibrium formulas were used to estimate the solid load as a function of the flow variables. Local erosion, due to the scour generated at the jump between two channels connected at different bottom elevations, was estimated adapting a literature formulation. The double order approximation time and space marching scheme, previously proposed for the solution of the unsteady flow problem in the fixed-bed case, is applied to the solution of the new system. The model was validated with both literature and new laboratory experimental data. No parameter calibration was used to fit the computed results to the experimental ones. 相似文献
858.
Jon F. Ihlefeld Mark D. Losego Ramòn Collazo William J. Borland Jon-Paul Maria 《Journal of Materials Science》2008,43(1):38-42
Polycrystalline barium titanate thin films have been prepared with 100 ppm of B-site acceptor dopants Ca, Mg, and Mn via chemical solution deposition on base metal substrates. The films are fired in low pO2 atmospheres at 900 °C to prevent substrate oxidation. All dopant species produce low loss, space-charge free material without secondary reoxidation anneals. We note that the dopant concentrations required to compensate for oxygen non-stoichiometry are substantially greater than expected by equilibrium thermodynamic calculations. This observation is rationalized in the context of a composite oxygen defect model with differing reduction enthalpies for grain interiors and surfaces. 相似文献
859.
860.
The viscosity of some routine hydrosoluble contrast media used in operational cholangiography (Bilignost and Verographin) was studied. The different viscosity of hepatic and vesical bile and of the contrast media was determined. This fact shows that the data of any direct cholangiography in accordance with the law of Hagen-Poiseuille is misinterpreted. As a result it may lead to a wrong surgical procedure, for example, sphincterotomy, and vice versa. 相似文献