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91.
92.
This randomized controlled trial evaluated the efficacy of a brief intervention designed to reduce the harmful consequences of heavy drinking among high-risk college students. Students screened for risk while in their senior year of high school (188 women and 160 men) were randomly assigned to receive an individualized motivational brief intervention in their freshman year of college or to a no-treatment control condition. A normative group selected from the entire screening pool provided a natural history comparison. Follow-up assessments over a 2-year period showed significant reductions in both drinking rates and harmful consequences, favoring students receiving the intervention. Although high-risk students continued to experience more alcohol problems than the natural history comparison group over the 2-year period, most showed a decline in problems over time, suggesting a developmental maturational effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
Campylobacter represents one of the leading causes of foodborne enteritis. Poultry and its products frequently transmit the pathogen. The objective of the present study was to model predictively the short-term inactivation of Campylobacter in a ready-to-eat poultry product to develop an economic high-pressure treatment. We inactivated baroresistant strains of Campylobacter jejuni and Campylobacter coli, grown to stationary phase on nutrient agar and inoculated in poultry meat slurry, by heat and high hydrostatic pressure. Incubation at ambient pressure at 70 degrees C for 1 min and at 450 MPa at 15 degrees C for 30 s inactivated more than 6 log CFU of this foodborne pathogen per ml of poultry meat slurry. Thermal and pressure inactivation kinetics of C. coli and C. jejuni in poultry meat slurry were accurately described by a first-order kinetic model. A mathematical model was developed from 10 to 65 degrees C and from ambient to 500 MPa that predicts the reduction in numbers of Campylobacter in response to the combination of temperature, pressure, and treatment time. We suggest the high-pressure treatment of foods to avoid health risks caused by Campylobacter. The nonthermal short-term treatment of the examined food model system represents a successful step to an economic high-pressure procedure.  相似文献   
94.
Two projects explored the links between language use and aging. In the first project, written or spoken text samples from disclosure studies from over 3,000 research participants from 45 different studies representing 21 laboratories in 3 countries were analyzed to determine how people change in their use of 14 text dimensions as a function of age. A separate project analyzed the collected works of 10 well-known novelists, playwrights, and poets who lived over the last 500 years. Both projects found that with increasing age, individuals use more positive and fewer negative affect words, use fewer self-references, use more future-tense and fewer past-tense verbs, and demonstrate a general pattern of increasing cognitive complexity. Implications for using language as a marker of personality among current and historical texts are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Most software packages available for particle tracing focus on visualizing steady or unsteady vector fields by using massless particle trajectories. For many applications, however, the use of massed and evaporating particles would provide a model of physical processes that could be used in product testing or design. In this article we describe the TrackPack toolkit, which provides an integrated interface for computing massless, massed, and evaporating particle trajectories in steady flow. In all cases, we assume a noncoupled model and compute particle trajectories through an existing vector field by numerically integrating with forward Euler, fourth-order Runge-Kutta, or an analytic streamline calculation. The TrackPack software effort was motivated by an industrial application to model pollution control systems in industrial boilers. We briefly describe the project and the visualization environment, and we demonstrate the necessity for massed, evaporating models in the application.  相似文献   
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A method for predicting the highly nonlinear stress-strain behavior and dilatation induced by cavitation of highly filled particulate composites from constituent properties has been developed. The approach presented uses a variation of linear elasticity throughout and has no adjustable parameters, unlike the methods currently used, which require large numbers of fitting factors and complicated nonlinear analyses. An energy balance derived from the first law of thermodynamics calculates critical strain values at which filler particles will debond when subjected to deformation. Repeated calculations of critical strain values using re-evaluated material properties accounting for the damage caused by debonding give very nonlinear stress-strain and dilatation curves. Experimentally observed dependencies on particle size, filler concentration, adhesion, and matrix and filler properties are correctly predicted. The method can be generalized for any state of stress or particle shape. Comparisons of experimental data with the model results give good agreement.  相似文献   
99.
Apigeninidin, a 3-deoxyanthocyanidin present in sorghum, was chemically synthesized and effectively purified by extracting impurities from aqueous 2 N HC1 into ethyl acetate. Apigeninidin (50mol) applied to filter paper disks inhibited the growth on agar plates of selected gram-positive bacteria (Bacillus cereus, Staphylococcus aureus, Staphylococcus epidermidis, andStreptococcus faecalis) and to a lesser extent gram-negative bacteria (Escherichia coli, Serratia marcens, andShigella flexneri). Apigeninidin was not mutagenic based on the Ames assay. The ability of apigeninidin to precipitate proteins from plant extracts could be physiologically important if it can be shown to bind to specific plant proteins.  相似文献   
100.
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