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11.
In this paper, we address the often contentious debate over state and local recycling policy by carefully estimating the social net benefit of curbside recycling. Benefits are estimated using household survey data from over 4,000 households across 40 western U.S. cities. We calibrate household willingnesstopay for hypothetical bias using an innovative experimental design that contrasts stated and revealed preferences. Cost estimates are compiled from previous studies by the U.S. Environmental Protection Agency and the Institute for Local Self Reliance, and from indepth interviews with recycling coordinators in our sampled cities. Across our sample of cities, we find that the estimated mean social net benefit of curbside recycling is almost exactly zero. On a citybycity basis, however, our social netbenefit analysis often makes clear predictions about whether a curbside recycling program is an efficient use of resources. Surprisingly, several curbside recycling programs in our sample appear to be inefficient. © 2006 by the Association for Public Policy Analysis and Management.  相似文献   
12.
Cannabinoid use was studied in a nonspecific population of postmortem urine specimens in the State of Maryland. Of 500 sequential specimens screened for cannabinoids by enzyme multiplied immunoassay EMIT, 63 (13%) were initially positive and 58 (12%) were confirmed positive (92%). It was observed that geographic location and race did not correlate with cannabinoid prevalence. Cannabinoid use was observed to be strongly age related, with peak use by the 21- to 25-year-old age group where 22% of the cases were positive. Use of cannabinoids was also closely linked to homicides, which represented nearly half of the positive cases but only 13% of the total cases. When comparing manner of death, the greatest percent of confirmed positives was seen in homicide (26%) and drug-related (17%) deaths. The incidence of cannabinoid use was found to be more than 3 times as great in drug-related (17%) as compared to natural deaths (5%). The percent of cannabinoid-positive cases from vehicle-related accidents was low (6%) and that from nonvehicle-related accidents somewhat higher (10%). Other drugs appeared in cannabinoid-positive cases. Most prevalent was ethanol N = 18, followed by morphine (from heroin, N = 11), quinine N = 11, and cocaine N = 11. Phencyclidine (PCP) occurred twice and several other drugs were reported only once. Of the 25 homicide cases screened for drugs, 64% were positive for some drug including ethyl alcohol. Thus it appears that a high percentage of homicide cases are drug related. Males greatly outnumbered females (56:2) in positive cases, but the number of female specimens received was small.  相似文献   
13.
A case is reported where phenol, a disinfectant, was ingested and resulted in the death of a 40-year-old white female. Concentrations of phenol were determined in blood (130 mg/L), urine (47 mg/L), bile (187 mg/L), brain (486 mg/kg), kidney (331 mg/kg), muscle (204 mg/kg), liver (228 mg/kg), and stomach content (668 mg) and compared to other cases reported in the literature.  相似文献   
14.
Liver tends to concentrate drugs in quantities generally higher than those found in blood or other body compartments. This fact as well as the general availability of liver in postmortem cases makes it an important specimen for comprehensive toxicologic investigation. A scheme for the analysis of liver for drugs with tissue hydrolysis, XAD-2 resin extraction, and TLC has been developed and the parameters affecting recovery have been studied. The hydrolysis of liver specimens at various pH conditions resulted in an improved recovery for morphine by using pH 2 (2N hydrochloric acid). Recoveries of barbiturates, codeine, and meperidine were essentially the same at pH 2 and pH 3. A considerable loss (22 to 55%) was observed for four drugs (pentobarbital, morphine, codeine, and meperidine) as a result of drug binding to the tissue pellets during the process of centrifuging the liver homogenates. This method is recommended as a comprehensive screening procedure for drugs in liver tissue. For quantitative purposes, however, it is necessary to determine a correction factor for all the losses occurring at the various steps of the procedure. This procedure compared favorably with other procedures for liver analysis reported in literature.  相似文献   
15.
A case is presented where phentermine, a sympathomimetic amine used as an anorectic drug, is believed to have significantly contributed to the death of an individual in whom other drugs were also found. Blood, urine, and tissue concentrations of phentermine are reported and compared to other cases in the literature.  相似文献   
16.
The incidence of drug and chemical related deaths was studied over a six-year period in the State of Maryland. Deaths were classified into the following categories: alcohol, carbon monoxide (CO), single drugs, multiple drugs, and narcotism. The last three categories were further subdivided as to the specific drugs or chemicals involved. Over the six-year period the number of alcohol and CO deaths remained steady, the number of barbiturate and propoxyphene deaths declined, while the number of tricyclic antidepressant drug deaths increased.  相似文献   
17.
Analyzing the Influence of Micro-Level Factors on CCTV Camera Effect   总被引:1,自引:0,他引:1  

Objectives

Despite the popularity of closed circuit television (CCTV), evidence of its crime prevention capabilities is inconclusive. Research has largely reported CCTV effect as “mixed” without explaining this variance. The current study contributes to the literature by testing the influence of several micro-level factors on changes in crime levels within CCTV areas of Newark, NJ.

Methods

Viewsheds, denoting the line-of-sight of CCTV cameras, were units of analysis (N = 117). Location quotients, controlling for viewshed size and control-area crime incidence, measured changes in the levels of six crime categories, from the pre-installation period to the post-installation period. Ordinary least squares regression models tested the influence of specific micro-level factors—environmental features, camera line-of-sight, enforcement activity, and camera design—on each crime category.

Results

First, the influence of environmental features differed across crime categories, with specific environs being related to the reduction of certain crimes and the increase of others. Second, CCTV-generated enforcement was related to the reduction of overall crime, violent crime and theft-from-auto. Third, obstructions to CCTV line-of-sight caused by immovable objects were related to increased levels of auto theft and decreased levels of violent crime, theft from auto and robbery.

Conclusions

The findings suggest that CCTV operations should be designed in a manner that heightens their deterrent effect. Specifically, police should account for the presence of crime generators/attractors and ground-level obstructions when selecting camera sites, and design the operational strategy in a manner that generates maximum levels of enforcement.  相似文献   
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19.
We present a test of the crime-deterrent effect of police-monitored street-viewing CCTV cameras using viewsheds of areas that were visible by cameras via direct line-of-sight and that were digitized using easily replicable methods, Google Maps, and standard GIS tools. A quasi-experimental research design, using camera installation sites and randomly selected control sites, assessed the impact of CCTV on the crimes of shootings, auto thefts, and thefts from autos in Newark, NJ, for 13 months before and after camera installation dates. Strategically-placed cameras were not any different from randomly-placed cameras at deterring crime within their viewsheds; there were statistically significant reductions in auto thefts within viewsheds after camera installations; there were significant improvements to location quotient values for shootings and auto thefts after camera installations. There was no significant displacement and there was a small diffusion of benefits, which was greater for auto thefts than shootings. The system of cameras in Newark is not as efficient as it could be at deterring certain street crimes; some camera locations are significantly more effective than others. Results of a system-wide evaluation of CCTV cameras should not be the only basis for endorsing or contesting the use of CCTV cameras for crime control or prevention within a city. Future research should test whether the effectiveness of CCTV cameras are dependent upon the micro-level attributes of environments within which they are installed.  相似文献   
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