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Abstract

This article uses culture of poverty and rational choice theories of poverty to explain how quickly nonelderly household heads leave public housing. Data from the Panel Study of Income Dynamics serve as the basis for the analysis.

Although a significant proportion of all household heads have public housing spells lasting five or more years, the majority have spells lasting less than five years. The availability of other housing options has a strong impact on how quickly individuals move out of public housing. Family structure and human capital play a more modest role. To the extent that one's childhood experiences affect the likelihood of exiting public housing, they appear to do so mostly through their effect on the acquisition of human capital. Finally, the evidence presented is inconsistent with the notion that public housing is a trap from which it is more difficult to escape the longer one lives in it.  相似文献   
254.
Neck injuries resulting from motor vehicle collisions (MVC), often referred to as whiplash trauma and injury, often demonstrate little or no evidence of significant tissue damage. In rare instances, however, serious injury to the anterior neck organ injuries can result from such trauma. The present study describes esophageal injury associated with rear-impact collisions, based on a unique case report, review of the scientific literature and a query in the National Automotive Sampling System (NASS) database of the US National Highway Traffic Safety Administration. The Medline search and present case study totaled five cases of rear-impact collision-related serious esophageal injury (laceration or rupture). In the four published cases all patients survived, whereas in the presented case study, the patient died due to mediastinitis and sepsis. The NASS query revealed an additional three cases out of a total of 55,926 investigated crashes. All three cases were associated with fatalities. Although no anatomical or bioengineering studies have presented data on the behavior of the esophagus during rear-impact whiplash loading, sudden tensile and/or compressive forces is the likely explanation of injury, often in combination with a local fracture of a vertebral body. In these 8 cases significant esophageal injury carried a substantial (50%) risk of mortality. Clinicians should be aware of the potential for significant complications in the whiplash trauma-exposed patient who complains of chest pain, mid-thoracic pain, discomfort in the neck and throat, respiratory distress, or hoarseness. For those forensic specialists involved in whiplash cases these study results highlight the need to consider esophageal injuries as a rare but potential consequence of whiplash trauma.  相似文献   
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Every year over 885,000 dog bites require serious medical attention. Based on human injury and insurance claims, six dog breeds were designated as "vicious" (Akitas, Chows, Dobermans, Pit Bulls, Rottweilers, and Wolf-mixes). This study was conducted to expand on previous research examining antisocial tendencies and personality styles of people choosing to own vicious breeds. Seven hundred and fifty-four college students completed a questionnaire assessing type of dog owned, criminal thinking, callousness, personality, alcohol usage, and deviant lifestyle behaviors. Vicious dog owners reported significantly higher criminal thinking, entitlement, sentimentality, and superoptimism tendencies. Vicious dog owners were arrested, engaged in physical fights, and used marijuana significantly more than other dog owners. However, the homogeneous sample utilized could impact the generalizability of these findings. Choosing to own a vicious dog may be a "thin slice" indicator of more antisocial tendencies.  相似文献   
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Abstract: The AutoMate Express? Forensic DNA Extraction System was developed for automatic isolation of DNA from a variety of forensic biological samples. The performance of the system was investigated using a wide range of biological samples. Depending on the sample type, either PrepFiler? lysis buffer or PrepFiler BTA? lysis buffer was used to lyse the samples. After lysis and removal of the substrate using LySep? column, the lysate in the sample tubes were loaded onto AutoMate Express? instrument and DNA was extracted using one of the two instrument extraction protocols. Our study showed that DNA was recovered from as little as 0.025 μL of blood. DNA extracted from casework‐type samples was free of detectable PCR inhibitors and the short tandem repeat profiles were complete, conclusive, and devoid of any PCR artifacts. The system also showed consistent performance from day‐to‐day operation.  相似文献   
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Population-based surveys suggest that methamphetamine use and abuse may be rising in the United States. However, little is known about methamphetamine use in eastern sections of the United States, particularly nonurban areas. The purpose of the present study was (a) to explore reported methamphetamine use and its correlates among Kentucky drug court clients and(b) to determine whether differences exist between methamphetamine users by drug court location. Of the 500 drug court clients surveyed, approximately 32% n=161) reported lifetime methamphetamine use. Methamphetamine users and nonusers differed in their drug-use profiles, self-reported criminal history, and number of criminal offenses. Nonurban and urban methamphetamine users differed in their drug-use profiles, psychological functioning, self-reported criminal history, and number of criminal offenses. These results suggest that differences exist between these populations and clinicians, and criminal justice officials may need to consider these differences when planning treatment and rehabilitation strategies.  相似文献   
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The PowerPlex 16 BIO multiplex short tandem repeat (STR) system contains the 13 CODIS loci (FGA, TPOX, D8S1179, vWA, D18S51, D21S11, TH01, D3S1358, CSF1PO, D16S539, D7S820, D13S317, and DS5S818), plus two pentanucleotide repeat loci (Penta D and Penta E) and the sex-identifying locus. Amelogenin. The PowerPlex 16 BIO System is optimized for use with the Hitachi FMBIO gel imaging systems. A consortium of seven independent laboratories collaborated to perform the studies defined by the FBI standards for performing a developmental validation, including the evaluation of sample concordance, percent stutter determination, nonprobative casework, precision, sensitivity, mixture determination, effect of substrates, the impact of environmental insults, and species specificity. All samples tested for concordance were consistent except for one sample from the Virginia Division of Forensic Science database that displayed discordance at D13S317, a locus whose primer sequence was altered. Stutter values were comparable to those of other STR multiplex systems, the precision was comparable to other multiplexes analyzed by gel electrophoresis, the DNA profiles were unchanged by the substrate upon which the blood samples were placed, and the nonprobative casework samples re-typed for the PowerPlex 16 BIO System were consistent with previous typing results. When greater than 0.125 ng of DNA was placed into the PowerPlex 16 BIO System amplification reaction, a full profile was generated by all laboratories. The mixture study results were comparable to those reported for other multiplex systems, the environmental study demonstrated a loss of larger molecular weight loci when samples were incubated at elevated temperatures for a prolonged period of time, and the only notable cross species hybridization was observed with primate DNA samples. This extensive validation work performed demonstrates that the PowerPlex 16 BIO System provides STR data of a quality comparable with other PowerPlex STR multiplex kits as well as other widely used STR multiplexes and is thus suitable for evidentiary casework analysis as well as database sample profiling.  相似文献   
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