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991.
Low participation rates in government assistance programs are a major policy concern in the United States. This paper studies take‐up of Section 8 housing vouchers, a program in which take‐up rates are quite low among interested and eligible households. We link 18,109 households in Chicago that were offered vouchers through a lottery to administrative data and study how baseline employment, earnings, public assistance, arrests, residential location, and children's academic performance predict take‐up. Our analysis finds mixed evidence of whether the most disadvantaged or distressed households face the largest barriers to program participation. We also study the causal impact of peer behavior on take‐up by exploiting idiosyncratic variation in the timing of voucher offers. We find that the probability of lease‐up increases with the number of neighbors who recently received voucher offers. Finally, we explore the policy implications of increasing housing voucher take‐up by applying reweighting methods to existing causal impact estimates of voucher receipt. This analysis suggests that greater utilization of vouchers may lead to larger reductions in labor market activity. Differences in take‐up rates across settings may be important to consider when assessing the external validity of studies identifying the effects of public assistance programs.  相似文献   
992.
Giorgios Kallis argues that Degrowth, as a pluralistic convergence of both theoretical perspectives and social movements, is part of a renewal of the critique of capitalism based on the ecological contradictions of this social order. In “Socialism without Growth” Kallis engages with other, more classical, approaches that have examined the contradictions of capitalism and the material conditions for a future, ecologically viable postcapitalist social order. After a quick exposition of the lineaments of a general theory of surplus and accumulation based on Bataille, Polanyi and Georgescu-Roegen, Kallis mobilizes Marx’s theory of accumulation to examine the growth drivers of capitalism. I will argue that economic growth in advanced capitalism can best be explained as a relation that articulates capitalist overproduction to overconsumption, and outline some analytical tools that such an explanation can provide to those interested in understanding the specific growth drivers of contemporary capitalism and their social and ecological consequences. This implies moving beyond the model outlined by Marx and mobilizing concepts and categories developed by the over-accumulation approach to capitalism, those developed by some of Degrowth’s most vocal Marxist critics, such as Foster. Through my dialogue with Kallis I will try and bridge these two approaches.  相似文献   
993.
This study focussed on the relationship between the use of seclusion and staff characteristics, such as number of nurses on shift, male-female staff ratio, level of education and level of work experience. A retrospective analysis of staff characteristics was applied to administrative data from ten wards in four mid-sized general psychiatric hospitals in the Netherlands. The data show that two variables were associated with seclusion rates: the male-female staff ratio and the variability in team's work experience. More female and less male nurses in a shift and less variability in team's work experience predicted an increase in seclusion rates.  相似文献   
994.
This paper proposes an alternative solution to multimetal deposition (MMD) for the development of latent fingermarks on non-porous and porous surfaces. MMD offers a good sensitivity, however it is very time-consuming and requires many reagents to be carried out. Single-metal deposition (SMD) replaces the silver enhancement of the gold colloids by a gold enhancement procedure. This reduces the number of baths by one as well as the number of reagents and their cost, utilizes reagents with a longer shelf life, and most importantly reduces the labor-intensity of the procedure. It offers quasi-identical results to MMD and thus makes a very attractive alternative.  相似文献   
995.
Amphetamine samples were analysed by gas chromatography-mass spectrometry (GC-MS), and the peak areas of 33 target compounds were transformed by applying various pretreatment techniques. The objective was to optimise the ability of a number of distance metrics to establish links between samples of amphetamine originating from the same batch (henceforth referred to as linked distances). Furthermore, partial least squares discriminant analysis (PLS-DA) was used to evaluate the effects of various pretreatment methods on separation of amphetamine batches synthesised by the Leuckart reaction, reductive amination of benzyl methyl ketone, and the nitrostyrene route. The most efficient way to pretreat GC-MS data varied for the different distance metrics, although best results were obtained when data were normalised to the sum of peak areas, and either the fourth root or a logarithm was applied to the normalised data. When pretreating normalised data by fourth root transformation, Pearson correlation was the distance metric that was most successful at finding linked samples. Normalisation and the use of fourth root also represented the best method of pretreating data when employing PLS-DA to separate samples synthesised by different routes. To achieve a faster and more user-friendly procedure for evaluating chromatograms, experiments were performed in which the number of target compounds used to compare samples was reduced. The effect of each compound that was removed was studied by applying PLS-DA and by using Pearson correlation to calculate linked distances as well as unlinked distances (between samples from different batches of amphetamine). Considering both links between samples from the same batch and separation of samples synthesised by different routes, the best results were obtained with the data set comprising 26 compounds. Finally, it was found that the profiling method developed in this work was superior to an existing technique with respect to separating linked and unlinked distances.  相似文献   
996.
Fifty-three head hair specimens were collected from 38 males with a history of cannabis use documented by questionnaire, urinalysis and controlled, double blind administration of delta9-tetrahydrocannabinol (THC) in an institutional review board approved protocol. The subjects completed a questionnaire indicating daily cannabis use (N=18) or non-daily use, i.e. one to five cannabis cigarettes per week (N=20). Drug use was also documented by a positive cannabinoid urinalysis, a hair specimen was collected from each subject and they were admitted to a closed research unit. Additional hair specimens were collected following smoking of two 2.7% THC cigarettes (N=13) or multiple oral doses totaling 116 mg THC (N=2). Cannabinoid concentrations in all hair specimens were determined by ELISA and GCMSMS. Pre- and post-dose detection rates did not differ statistically, therefore, all 53 specimens were considered as one group for further comparisons. Nineteen specimens (36%) had no detectable THC or 11-nor-9-carboxy-THC (THCCOOH) at the GCMSMS limits of quantification (LOQ) of 1.0 and 0.1 pg/mg hair, respectively. Two specimens (3.8%) had measurable THC only, 14 (26%) THCCOOH only, and 18 (34%) both cannabinoids. Detection rates were significantly different (p<0.05, Fishers' exact test) between daily cannabis users (85%) and non-daily users (52%). There was no difference in detection rates between African-American and Caucasian subjects (p>0.3, Fisher's exact test). For specimens with detectable cannabinoids, concentrations ranged from 3.4 to >100 pg THC/mg and 0.10 to 7.3 pg THCCOOH/mg hair. THC and THCCOOH concentrations were positively correlated (r=0.38, p<0.01, Pearson's product moment correlation). Using an immunoassay cutoff concentration of 5 pg THC equiv./mg hair, 83% of specimens that screened positive were confirmed by GCMSMS at a cutoff concentration of 0.1 pg THCCOOH/mg hair.  相似文献   
997.
The General Agreement on Trade in Services (GATS) negotiatorsfaced a significant challenge when having to craft a comprehensiveset of disciplines governing multilateral trade in services,and the result is somewhat complex. Some obligations, in particularthe most favoured-nation treatment (MFN) obligation, apply acrossthe board. Others, like the market access and national treatmentobligations, apply only in respect of service sectors of a Member'schoosing. There is overlap between the market access and nationaltreatment obligations, and the relationship between these twodisciplines and those on domestic regulation is not clearlyestablished. Additional obligations have been adhered to ona voluntary basis, in particular in the areas of telecommunicationsand financial services. In general, the interpretation and understandingof Members’ Schedules of Specific Commitments proves tobe a laborious exercise. This provides fertile ground for difficultand often sensitive interpretive issues to arise. Although Membershave thus far not made extensive use of dispute settlement proceduresto resolve them, existing World Trade Organization (WTO) decisionsalready show the reach of GATS disciplines and their potentialimpact on Members’ policies and regulations. The Gamblingcase has, in particular, sparked a debate as to what shouldbe the right balance between trade constraints and the autonomyof Members’ service regulators. This article reviews theGATS case law with a view to offering a critical assessmentof the main systemic issues that have been addressed by WTOadjudicatory bodies. These issues are, respectively, the scopeof application of the GATS, the interpretation of specific commitmentsin Members’ Schedules, market access, non-discriminatorytreatment, and general exceptions.  相似文献   
998.
During the examination of light bulbs from a vehicle involved in a road accident, the headlights did not reveal any evidence regarding whether they were energized or not. Additionally, a police officer turned the lights on after the accident to verify their functioning, thus damaging some of the evidence. By examining the vehicle, it was determined that the park lights could provide answers regarding the conditions of the headlights. After observations, it was concluded that the park lights and headlights were off at the time of the impact. This case report demonstrates how important it is to integrate the circumstances surrounding the case into the interpretation of the results. Nevertheless, it also demonstrates the necessity for examining both the vehicle and all light bulbs in order to reach the most pertinent and proper conclusion.  相似文献   
999.
This report describes a cold case in which a cadaver of a 28-year-old female was exhumed in February 2005 from a cemetery in Battle Creek, Michigan. She had sustained a gunshot wound to the head and was found dead in her home on November 15, 1977. The body of the victim was subsequently embalmed and then buried at a depth of 1.8 m in an unsealed casket that was placed inside an unsealed cement vault. The exhumation yielded thousands of live specimens of a single species of the order Collembola or spring tails, Sinella (Coecobrya) tenebricosa (Entomobryidae). This species is considered to be a "tramp" species, cosmopolitan in the United States and Canada. Due to the ideal environmental conditions at the site, the population of this species underwent growth and development inside the casket for a number of years. Collected with the Collembola were large numbers of Acarina (mites) of the Family Glycyphagidae, and fly puparia, Conicera tibialis Schmitz (Order: Diptera, Family: Phoridae), also known as coffin flies. These invertebrates are sometimes mentioned by forensic investigators as occurring on corpses in graves, but aspects of their life history are rarely described. The species of Collembola that was found surviving and reproducing on this corpse in a casket exhumed after 28 years was the oldest reported grave site occurrence for any collembolan species based on a survey of the literature back to 1898.  相似文献   
1000.
This article examines the legacy of lynchings on contemporary whites' views of blacks as criminal threats. To this end, it draws on prior literature on racial animus to demonstrate the sustained influence of lynching on contemporary America. We hypothesize that one long‐standing legacy of lynchings is its influence in shaping views about blacks as criminals and, in particular, as a group that poses a criminal threat to whites. In addition, we hypothesize that this effect will be greater among whites who live in areas in America where socioeconomic disadvantage and political conservatism are greater. Results of multilevel analyses of lynching and survey data on whites' views toward blacks support the hypotheses. In turn, they underscore the salience of understanding historical forces, including the legacy of lynchings that influence contemporary views of blacks, criminals, and punishment policies.  相似文献   
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