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991.
Environmental samples from indoor surfaces can be confounded by dust, which is composed largely of human skin cells and has been documented to contain roughly tens of micrograms of total DNA per gram of dust. This study complements previous published work by providing estimates of the quantity of amplifiable human DNA found in environmental samples from a typical indoor environment, categorized by the intensity of human traffic and visible quantity of dust. Dust was collected by surface swabbing standard 576 cm2 areas in eight locations, and evaluated for total DNA quantity, presence of human DNA (mitochondrial and nuclear loci using conventional PCR), quantity of human nuclear DNA using quantitative PCR, and STR analysis. The total DNA content of 36 dust samples ranged from 9 to 28 ng/cm2, and contained 0.2–1.1 pg/cm2 of human DNA. Overall, human DNA was detected in 97% of 36 dust samples and 61% of samples yielded allele distributions of varying degrees of complexity when subjected to STR analysis. The implications of this study are twofold. First, the presence of dust in evidence can be a significant contamination source in forensic investigations because the human DNA component is of sufficient quality and quantity to produce allele calls in STR analysis. This can be effectively managed by implementing stringent protocols for collection and analysis of potential biological samples. A second implication is the use of dust as a source of evidence for identification of inhabitants within a defined location. In the latter case, a number of additional studies would be necessary to identify relevant pretreatments for environmental dust samples and to develop the necessary deconvolution techniques to separate the composite genotypes obtained.  相似文献   
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Research Summary The Local Law Enforcement Block Grants (LLEBG) Program was second only to the Community‐Oriented Policing Services (COPS) Program in its funding levels. Some $3 billion was dispensed to local jurisdictions to reduce crime and improve public safety; yet the effects of LLEBG funding on crime have been all but ignored. Accordingly, panel data from more than 5,000 cities covering a 12‐year period (1990–2001) were collected, and index crime rates were regressed on LLEBG funding and appropriate demographic controls. Additional controls for police levels and other federal grants were also introduced, proper checks for endogeneity of grants (and police levels) were performed, and the models were subjected to an array of robustness checks. A consistent message emerged: LLEBG Program funding was associated with significant reductions in serious crime. Policy Implications Although LLEBG funding seemed to reduce serious crime, the results also revealed that the decrease did not occur through the hiring of additional police officers, even though many funds were used for that purpose. Other mechanisms were thus at work, but the data did not provide insights into what these mechanisms were. In any case, every $1 in LLEBG funding per capita was associated with approximately 59 fewer index crimes per 100,000 people. When combined with the findings from recent studies of the effects of community policing grants on crime, this study suggests additional federal support for local law‐enforcement agencies should be considered.  相似文献   
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Interpretation of unusual wounds caused by firearms.   总被引:1,自引:0,他引:1  
The interpretation of the range of fire of gunshot wounds requires coordination of information and observations from the autopsy surgeon, scene investigator, and laboratory analyst. Opinions based on incomplete information often lead to misinterpretation of the wound. The effects of interposed targets such as clothing, windows, and body parts are discussed. Case examples are given for interposed targets that cause confusing patterns and even lead to misidentification of the points of entrance and exit of the projectile in the body. The splitting of tissue in areas of bony prominence can be mistaken for evidence of discharge of a firearm at close range.  相似文献   
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All cases in which hyperthermia had been determined as the basic cause of death during the period 1970-86 were collected from the records of the Central Statistical Office of Finland. Of the total of 230 cases, 228 were included in the present study; the two remaining victims died abroad, and no autopsy was performed in Finland. Most of the hyperthermia deaths occurred while the decedent was taking a sauna bath; most decedents were men aged 42-62 years. An increase in the total number of hyperthermia deaths, and of male victims, was noted from the beginning of the 1970s onward; the number of female victims remained at a relatively steady level throughout, with the exception of a slight rise in 1986. Acute alcohol consumption was detected in most of the victims; in some cases there was also a reference to chronic alcoholism or recent long-term heavy drinking. The findings suggest that in addition to the acute hazardous effect of ethanol on thermoregulatory mechanisms, the long-term consumption of alcohol may have promoted fatal hyperthermia in these subjects.  相似文献   
1000.
Climate science research documents and predicts changes in the physical environment. This information informs policy decisions and public programs through the design of human interventions that promote adaptive management. Since the early 2000s, federal funding has led to the creation of transdisciplinary regional climate workgroups to facilitate integrative knowledge coproduction and promote shared use of research results by scientific and nonscientific stakeholders. Labeled “boundary organizations,” these workgroups are tasked with facilitating partnerships between climate science researchers and practitioners with expertise in multiple physical and social science disciplines. When these organizations are successful, scientific findings and practitioner experiences are integrated to synergistically create usable knowledge about adaptive management that provides direct public value and creates broader societal impacts. This article explores the broader impacts provided by these boundary organizations through the establishment of regional research agendas and the communication of research results in ways that influence regional public policy and promote adaptive management.  相似文献   
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