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A monolithic capillary electrophoresis system with integrated on-chip fluorescence detector has been microfabricated on a silicon substrate. Photodiodes in the silicon substrate measure fluorescence emitted from eluting molecules. The device incorporates an on-chip thin-film interference filter that prevents excitation light from inhibiting the fluorescence detection. A transparent AZO conducting ground plane is also used to prevent the high electric fields used for the separation from interfering with the photodiode response. Separations of DNA restriction fragments have been performed in these devices with femtogram detection limits using SYBR Green I intercalating dye. 相似文献
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Air sparging is a relatively new, cost-effective technology for the remediation of soil and groundwater contaminated with volatile organic compounds (VOCs). While the method has met with reasonable success at a large number of field sites, implementation of the technique is restricted to relatively coarse-grained soils with large values of air permeability, which significantly limits its applicability. An understanding of the fundamental parameters that control the formation and distribution of air in the sparging process is useful for optimizing the system implementation and extending its range of applicability. This work presents the results of an experimental investigation into the effect of process control parameters on the size and size distribution of air bubbles produced in aqueous and idealized saturated porous media systems. The experiments used digital image analysis to image and quantify the physical characteristics of the bubbles generated in a bench scale test cell. Results demonstrated that the average bubble size and range of size distribution increased as the injection pressure and size of the injection orifice were increased. Larger diameter bubbles with wider size distributions were produced in the presence of particles when compared to aqueous systems. As the particle size was decreased, the size of bubbles produced increased. Finally, the presence of trace quantities of the surfactant Triton X100 led to uniformly small diameter bubbles under all experimental conditions. The presence of the surfactant coating produced bubbles with physical characteristics that are more suited to in situ stripping of VOCs than the bubbles produced in the absence of a surfactant. 相似文献
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Objective: Therapeutic processes in cardiac rehabilitation programs are virtually unexamined. Models were tested by which changes in the working alliance between patient and staff (agreement on goals/tasks; emotional bond) may affect outcomes in conjunction with changes in patient self-efficacy to change their diets and increase exercise. Design: Cardiac patients (n = 79) participated in a 12-week program, and completed assessments at early, mid, and late treatment. Main Outcome Measures: Changes in cardiac depression, physical health, perceived exertion during exercise, rate/pressure product at submaximal exercise tolerance, weight loss, return to work, total fat intake. Results: Early-treatment changes in agreement on goals/tasks were related to changes in psychosocial factors and perceived exertion during exercise independent of effects of changes in self-efficacy. Early-treatment changes in goals/tasks and self-efficacy interacted to predict changes in cardiorespiratory fitness, weight loss, and return to work such that patients high on both goals/tasks and self-efficacy showed the most gains. Conclusion: Sound therapeutic relationships between patients and staff may play an important role in facilitating the achievement of a wide-range of salutary outcomes during cardiac rehabilitation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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James McIntosh Andrew Flanagan Nora Madden Maurice Mulcahy Lawrence Dargan Michael Walker Duncan Thorburn Burns 《International Journal of Food Science & Technology》2011,46(8):1569-1574
The only current effective treatment for coeliac disease (CD) is a lifelong diet that is as free from gluten as possible. This study provides baseline evidence to inform future interventions of benefit to CD sufferers by examining awareness of CD issues by food servers and preparation staff, assessing their claims to provide gluten‐free foods by analysis of a meal concurrently sampled. While the majority of attempts to purchase a ‘gluten‐free’ meal on request in restaurants were successful, some 10% of all samples contained gluten, 2.7% between 21 and 100 mg kg?1, and 7.7% >100 mg kg?1 and two unsatisfactory samples were purchased from so‐called coeliac‐friendly restaurants. These findings were consistent with those obtained previously by Collin et al. [Alimentary Pharmacology & Therapeutics 19 (2004) 1277], Størsrud et al. [European Food Research & Technology 217 (2003) 481], Gélinas et al. [International Journal of Food Science & Technology 43 (2008) 1245] for cross contamination with gluten. Staff confidence, ‘gluten‐free’ notices, signs and menu choices were no guarantee of risk‐free dining for CD sufferers. Based on our findings we suggest the need for further training, specifically for chefs and managers. 相似文献
76.
PURPOSE: Organized interscholastic athletics are an integral part of the educational program at almost every school level. With this growing popularity of sports and their inclusion in more public school programs, it becomes increasingly apparent that additional consideration must be given to the injury problem associated with sport. The North Carolina High School Athletic Injury Study (NCHSAIS) was undertaken to identify patterns of injury among male and female athletes in North Carolina high schools participating in any of 12 sports. Specific aims are to measure the incidence, severity and etiology of injuries; to determine the relationship of demographic factors and protective equipment, exposure to play, and school characteristics to injuries; to study the relationship of coaches' training and experience to injury occurrence; and to compare the incidence and severity of injury among female and male athletes in the same or comparable sports. METHODS: A two-stage cluster sample of 100 high schools in North Carolina was selected for this 4-yr prospective study. RESULTS: Participation by the initial sample or a random replacement was achieved for 91 of the 100 schools. Nonresponse occurred at multiple levels of the sample for this study, and the weekly participation form posed the greatest respondent burden. CONCLUSIONS: The NCHSIAS offers a successful methodology for addressing sports injuries. In this paper we describe the design, methodology, and implementation issues that emerge in conducting a large scale epidemiological study in a population of high school athletes. 相似文献
77.
Compton Scott N.; Burns Barbara J.; Egger Helen L.; Robertson Elizabeth 《Canadian Metallurgical Quarterly》2002,70(6):1240
This article reviews the empirical literature on psychosocial, psychopharmacological, and adjunctive treatments for children between the ages of 6 and 12 with internalizing disorders. The aim of this review was to identify interventions that have potential to prevent substance use disorders in adolescence by treating internalizing disorders in childhood. Results suggest that a variety of behavioral, cognitive-behavioral, and pharmacological interventions are effective in reducing symptoms of childhood depression, phobias, and anxiety disorders. None of the studies reviewed included substance abuse outcomes. Thus, little can be said about the relationship between early treatment and the prevention of later substance use. The importance of evaluating the generalizability of research-supported interventions to community settings is highlighted and recommendations for future research are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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