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Philip Gleason 《Journal of policy analysis and management》2008,27(1):82-103
Under the policy of direct certification for free school meals, school districts use information shared by state agencies about household eligibility for means‐tested programs in the state in order to determine the potential eligibility for free meals of students enrolled in the district. This information allows districts to automatically approve students in these eligible households for free meals without requiring the household to complete the application process. This paper examines the impacts of direct certification on students' likelihood of becoming certified for free meals, using data from a national survey of school food service directors as well as statelevel administrative data on program participation. A state‐level fixed effects model is estimated to account for the possibility of selection bias. The key finding is that direct certification leads to a statistically significant increase in the number of children getting free school meals. More generally, this finding highlights a promising approach for improving access to means‐tested programs without compromising program integrity. © 2008 by the Association for Public Policy Analysis and Management. 相似文献
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Excretion of alcohol in urine and diuresis in healthy men in relation to their age, the dose administered and the time after drinking 总被引:1,自引:0,他引:1
A W Jones 《Forensic science international》1990,45(3):217-224
Healthy male volunteers drank neat whisky in amounts corresponding to 0.51, 0.68, or 0.85 g ethanol/kg body weight in 15-25 min after an overnight (10 h) fast. Urine was collected immediately before drinking and then at 60 min intervals for 7-8 h after intake. The volumes of urine voided were measured and the concentrations of alcohol (UAC) were determined by an enzymatic method. Ethanol-induced diuresis showed large inter-subject variations. The flow of urine was maximum between 60 and 120 min post-drinking when the median rates of production were 117 ml/h (range 55-335), 113 ml/h (range 41-453) and 373 ml/h (range 215-485) for 0.51, 0.68, and 0.85 g ethanol/kg respectively. The output of urine returned to normal (30-60 ml/h) after the peak UAC had passed despite an elevated blood alcohol concentration (BAC). The average amount of alcohol excreted in urine was 0.29 g (S.D. 0.119), 0.44 g (S.D. 0.246), and 1.00 g (S.D. 0.427) after the consumption of 0.51, 0.68 and 0.85 g ethanol/kg respectively. Neither peak diuresis nor the amount of alcohol excreted depended on a subject's age between 20 and 60 years. This work shows that after drinking a moderate dose of alcohol, only 0.7-1.5% of the amount consumed is excreted unchanged in urine. Ethanol-induced diuresis is most pronounced for the first 1-2 h after drinking (rising BAC). The production of urine returns to normal during the post-absorptive state. 相似文献
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