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81.
Dimethyl sulphide formation in malt occurs primarily during the kilning process, and is significantly dependent upon the maximum kilning temperature. During mashing a considerable fraction of the dimethyl sulphide of malt is transferred to the wort. Since this is not always completely removed by the wort boiling process, the remaining dimethyl sulphide, although decreased during fermentation, may be sufficient to impart a noticeable dimethyl sulphide aroma to the finished beer.  相似文献   
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The function of organic solar cells is based upon charge photogeneration at donor/acceptor heterojunctions. In this paper, the origin of the improvement in short circuit current of poly(3‐hexylthiophene)/6,6‐phenyl C61‐butyric acid methyl ester (P3HT/PCBM) solar cells with thermal annealing is examined. Transient absorption spectroscopy is employed to demonstrate that thermal annealing results in an approximate two‐fold increase in the yield of dissociated charges. The enhanced charge generation is correlated with a decrease in P3HT's ionization potential upon thermal annealing. These observations are in excellent quantitative agreement with a model in which efficient dissociation of the bound radical pair into free charges is dependent upon the bound radical state being thermally hot when initially generated, enabling it to overcome its coulombic binding energy. These observations provide strong evidence that the lowest unoccupied molecular orbital (LUMO) level offset of annealed P3HT/PCBM blends may be only just sufficient to drive efficient charge generation in polythiophene‐based solar cells. This has important implications for current strategies to optimize organic photovoltaic device performance based upon the development of smaller optical bandgap polymers.  相似文献   
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In this report, we conducted a secondary analysis of the Treatment of SSRI-Resistant Depression in Adolescents (TORDIA) study to explore the impact of specific cognitive–behavioral therapy (CBT) treatment components on outcome. In TORDIA, 334 youths (ages 12 to 18 years) with major depressive disorder who had failed to respond to an adequate course of selective serotonin reuptake inhibitor (SSRI) medication were randomized to a medication switch (either to an alternative SSRI or venlafaxine) with or without 12 weeks of adjunctive CBT. Participants who had more than 9 CBT sessions were 2.5 times more likely to have adequate treatment response than those who had 9 or fewer sessions. CBT participants who received problem-solving and social skills treatment components, controlling for number of sessions and other confounding variables, were 2.3 and 2.6 times, respectively, more likely to have a positive response. These preliminary findings underscore the importance of receiving an adequate number of sessions to attain an adequate clinical response. Finally, social skills and problem solving may be active elements in CBT for adolescent depression and should be considered in treatment by those working with seriously depressed youths. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
Within 12 months of the discovery of X rays in 1895, papers appeared in the literature reporting adverse effects from high exposure. In 1925, the first International Congress of Radiology, held in London, considered the need for a protection committee, which it established at its second congress in Stockholm in 1928. This paper celebrates the 80th anniversary of ICRP by tracing the history of the development of its policies, and identifying a few of the personalities involved from its inception up to the modern era. The paper follows the progress from the early controls on worker doses to avoid deterministic effects, through the identification of stochastic effects, to the concerns about public exposure and increasing stochastic risk estimates. The key features of the recommendations made by ICRP from 1928 up to the most recent in 2007 are identified.  相似文献   
85.
A broad variety of juridical requirements has to be considered during the development of Web-applications. Disregard of these requirements holds severe financial dangers. A complete compilation of juridical requirements is complicated due to the multitude of juridical areas and the variety of Web-applications. Therefore, a development-driven juridical framework is suggested. From a software engineering point of view it is crucial to capture requirements at an early stage of development in order to avoid much higher costs at a later time. Thus, specialized conceptual modelling methods are examined with regard to their capability to model juridical requirements. A lack of methodical support is identified which is addressed by a systematic adaption and extension of the eW3DT method.  相似文献   
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To examine the effects of recombinant human erythropoietin (rHuEPO) on hospital utilization, hospital costs, and Medicare reimbursements for hospital care, a longitudinal, matched cohort study was conducted using Medicare claims data of 23,806 Medicare-eligible, dialysis patients who received rHuEPO, did not have a transplant, and were alive for 18 mo or longer and 22,720 controls matched on age, sex, race, cause of ESRD, and dialysis modality. The relative odds (rHuEPO versus control) of admission for all causes and for specific causes over 9 mo, adjusted for admission in the prior 9 mo and the per patient change in total admissions, inpatient days, hospital costs, and Medicare hospital payments between the prior 9-mo period and the subsequent 9-mo period was examined. The adjusted relative odds (95% confidence interval) of admission (rHuEPO versus control) was: higher and statistically significant for all causes, 1.08 (1.03 to 1.14); seizure, 1.52 (1.28 to 1.75); vascular access revision, 1.11 (1.06 to 1.17), and heart failure, 1.17 (1.09 to 1.26); higher but not statistically significant for angina, 1.09 (0.99 to 1.20) and stroke, 1.08 (0.86 to 1.31); and lower but not statistically significant for myocardial infarction, 0.91 (0.72 to 1.10); peripheral vascular disease, 0.81 (0.60 to 1.02); anemia, 0.86 (0.56 to 1.17); and depression, 0.89 (0.37 to 1.40). The mean change per 1,000 patients in admissions was less by 38 (P = 0.03) because of fewer readmissions, and in days was 1,309 less (P < 0.001), for patients treated with rHuEPO versus controls. The mean change per patient in hospital costs was $371 less and was statistically significant (P = 0.03) and in Medicare hospital payments was $132 less but was not statistically significant (P = 0.43) for patients treated with rHuEPO versus controls. rHuEPO was associated with an increase in the probability of hospital admission (particularly admissions potentially related to adverse effects) but a decrease in readmissions, overall admissions, hospital days, and cost to hospitals in this cohort of patients surviving for 18 mo. Although not realized short term, Medicare savings from potential rHuEPO-related reductions in hospital care may be long term through future adjustments in diagnosis-related group-based hospital payment.  相似文献   
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