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41.
Some theoretical results are compared with experimental measurements of pressure on a given delta wing. An investigation of the differences between two sets of theoretical results obtained by different computational procedures has been carried out. Explanations of the causes of the diferences are given and it is shown that theoretical results which are in close agreement with each other can be produced by the different methods. It is argued that the theoretical pressure distribution resulting from applying the use of inviscid theory, has been calculated now with reasonable accuracy, and that remaining differences between theory and experiment are probably due to viscous boundary layer effects.  相似文献   
42.
Behavioural responses to psychostimulant drugs can be profoundly affected by early environmental influences. The aim of this study was to describe the effects of repeated brief separations of rat pups from their dams during the early neonatal period on cocaine self-administration behaviour as adults. Lister hooded rats exposed to a repeated maternal separation procedure (REMS) showed altered acquisition and maintenance of cocaine self-administration as adults, the effects being dose and gender-dependent. Overall, the patterns of acquisition of self-administration across three doses of cocaine (0.05, 0.08 and 0.5 mg/injection) suggested a rightward shift in the acquisition dose-effect functions for the REMS animals relative to control animals. At 0.05 mg/injection, there was a retarded acquisition of cocaine self-administration in male and female neonatally separated rats. At 0.08 mg/injection there was a facilitated acquisition in female neonatally separated subjects. After establishment of stable self-administration of the training dose, in the same cohort of subjects, rightward and downward shifts in the cocaine self-administration dose-effect functions were determined for female and male REMS subjects, respectively, relative to their controls. The dose-effect function for both female groups was shifted to the left of that of the respective male groups, although the lighter body weights of the females meant that they administered a higher unit dose per unit body weight than the males. Whereas male REMS subjects tended to self-administer less cocaine than the controls at the dose eliciting maximal responding (0.03 mg/injection) and to make fewer lever responses overall at each dose tested, female REMS subjects self-administered significantly more cocaine than their respective controls at a dose of 0.03 mg/injection. There was no differential sensitivity to the rate-altering effects of the selective dopamine D2 receptor antagonist, eticlopride, or to the selective dopamine D1 receptor antagonist, SCH 23390. These data provide further evidence that altered early environment affects drug-taking behaviour in a developmentally specific and gender-specific manner, with the effects of neonatal separation contrasting with previously published data on the effects of post-weaning isolation rearing.  相似文献   
43.
The paper outlines a systemic approach to understanding and assessing safety capability in the offshore oil and gas industry. We present a conceptual framework and assessment guide for understanding fitness-to-operate (FTO) that builds a more comprehensive picture of safety capability for regulators and operators of offshore facilities. The FTO framework defines three enabling capitals that create safety capability: organizational capital, social capital, and human capital. For each type of capital we identify more specific dimensions based on current theories of safety, management, and organizational processes. The assessment guide matches specific characteristics to each element of the framework to support assessment of safety capability. The content and scope of the FTO framework enable a more comprehensive coverage of factors that influence short-term and long-term safety outcomes.  相似文献   
44.
Cyclical texture profile analysis (TPA) parameters measured using a star-shaped probe with two cycles of 80% penetration and Warner-Bratzler shear force (WBS) were compared as predictors of objective tenderness and subjective sensory characteristics of rib steaks from 52 beef loins. The TPA parameters of hardness, cohesiveness and chewiness were negatively correlated (P<0.05) with trained panel sensory characteristics of initial tenderness (r=−0.64, −0.41, −0.62, respectively), amount of connective tissue (r=−0.57, −0.27, −0.55, respectively), overall tenderness (r=−0.68, −0.39, −0.64, respectively) and overall palatability (r=−0.56, −0.37, −0.53, respectively). These sensory characteristics were also negatively correlated (P<0.05) with WBS (r=−0.61, −0.49, −0.60, −0.56, respectively). Stepwise regression analysis generated prediction equations that included the TPA parameters of hardness and adhesiveness, which accounted for 47, 36, 51 and 38% of the variation in initial tenderness, amount of connective tissue, overall tenderness and overall palatability, respectively. Prediction equations using WBS accounted for 37, 24, 36 and 31% of the variation in initial tenderness, amount of connective tissue, overall tenderness and overall palatability, respectively. Hence, TPA explained more of the variation in subjective sensory tenderness of the rib steaks than WBS.  相似文献   
45.
Presumably, dry-ageing enhances flavour attributes of meat by surface desiccation to increase and modify fatty acid content and other organoleptic molecules. However information regarding dry-ageing of fresh pork is limited. To examine the effects of dry-ageing on pork quality, Large White (LW, n = 24) and Large White × Duroc (Duroc, n = 24) barrows were slaughtered and three longissimus thoracis et lumborum sections from each side of the carcass were wet or dry-aged for 2, 7 or 14 d. Dry-aged meat had lower (P < 0.001) moisture and higher (P < 0.001) protein content due to higher purge losses (P < 0.001) when compared with wet aged meat. However no dry-ageing effect (P > 0.05) was observed on sensory characteristics. The increase in the duration of ageing decreased moisture content and drip loss and increased (P < 0.001) protein content, purge loss and L*, chroma and hue values. These changes were more accentuated in dry-aged meat (P < 0.01). Days of ageing dependent increases (P < 0.001) were observed for instrumental and sensory tenderness and juiciness in both ageing types. Moreover, meat from Duroc barrows had lower (P < 0.001) moisture and protein content, and higher (P < 0.01) fat content, L* and hue values. Instrumental and sensory tenderness, juiciness and flavour were higher (P < 0.01) in meat from Duroc than LW barrows. Increases (P < 0.01) in flavour intensity and decreases in off-flavour of meat from LW barrows were greater (P < 0.05) in d 7 than in d 14. Therefore the duration of ageing affected most quality and sensory characteristics, while the changes to quality attributes of dry versus wet-aged pork were attributable to the differences in shrink losses in the present study.  相似文献   
46.
OBJECTIVE: The authors tested the hypotheses that medical illness burden is independently associated with depression and that this association is moderated by neuroticism. METHOD: Multiple regression techniques were used to determine the independent associations of medical burden and neuroticism with depression in a group of 196 subjects, 60 years of age and older, recruited from primary care settings. RESULTS: Medical burden and neuroticism were independently associated with major depression, depressive symptoms, and psychiatric dysfunction. CONCLUSIONS: These findings support models in which medical disorders may contribute directly to depression. At the same time, the role of neuroticism in later-life depression warrants further study.  相似文献   
47.
In its recent reengineering efforts, the Mount Sinai Hospital developed economic tools to assure that this major restructuring project would reach its predetermined financial objectives. We discuss how these tools were designed and implemented and what impact they had.  相似文献   
48.
A novel single-step microbial transformation process for the production of testosterone (TS) from cholesterol by Mycobacterium sp was investigated. It was found that the supply of reducing power, NADH, from the metabolism of glucose was necessary for the reduction of androst-4-en-3,17-dione (AD) to TS. The cultivation time for the maximum accumulation of TS and the residual glucose increased in parallel with the amount of glucose supplemented in fermentation cultures. After the glucose in the fermentation culture was completely consumed, most of the TS was oxidized to AD. Adding a larger amount of glucose could prevent oxidation of TS to AD. Under optimal fermentation conditions, the maximum molar conversion rate of TS from cholesterol was 51% in a 5-L surface-aerated fermentor after 120 h cultivation.  相似文献   
49.
Testing hypotheses derived from regret and mood management theories, this research explores how regretted experiences impact interest in viewing experience-relevant TV programming and such viewing's effects on program enjoyment and felt regret. One hundred and forty-four participants, half of whom had been unfaithful in romantic relationships, were asked first to rate their interest in viewing a series of storylines and then to provide their reactions to 1 of 2 versions of a TV program depicting cheating behavior. Largely consistent with hypotheses, results indicated that those who had both cheated and felt regret about their behavior were more likely than others to want to watch experience-related storylines, were no less likely to enjoy watching such programming, and particularly preferred viewing the program version in which the main character rationalized, rather than expressed regret for, her behavior. Both program versions, however, reduced regret equally. A survey of 206 city residents also offered evidence consistent with predictions based on regret theory. Overall, this research speaks to the value of integrating theories of emotion with media theory to enhance the latter's predictive ability.  相似文献   
50.
Organic sulfur biodesulfurization in non-aqueous media   总被引:3,自引:0,他引:3  
William R. Finnerty 《Fuel》1993,72(12):1631-1634
An alternative approach to water-based biodesulfurization systems was examined employing organic solvent-based reaction media. A gram-position microorganism, FE-9, was developed to function biocatalytically against organic sulfur-containing heterocycles in 100% dimethylformamide. Strain FE-9 converted dibenzothiophene to biphenyl and hydrogen sulfide under a hydrogen atmosphere, and to biphenyl, hydroxybiphenyl and sulfate under an air atmosphere. Thianthrene was converted to benzene and hydrogen sulfide under a hydrogen atmosphere, and to benzene and sulfate under an air atmosphere. The bioconversion of sulfur-containing heterocycles to aromatic hydrocarbons and hydrogen sulfide, and the oxidation of sulfide to sulfate under air, appears to represent two different biochemical events occurring in dimethylformamide. These studies indicate a strong potential for the development of biocatalysts that selectively abstract organosulfur from high-sulfur containing fossil fuels in an organic solvent-based reaction medium.  相似文献   
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