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211.
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Abstract:  In response to the unexpected paucity of blood/tissue spatter at the site where a body of an adult woman was dismembered by an electric chainsaw, we dismembered two large pig carcasses with a small electric chainsaw in a controlled environment. These experiments demonstrated first that a large carcass could be easily dismembered by a small electric chainsaw. When the chainsaw bar is held parallel to the ground the majority of the blood and tissue is deposited directly beneath the saw and bar and very little elsewhere. If the discharge chute of the saw however is not oriented directly at the ground, larger amounts of blood and tissue may be sprayed on lateral surfaces or deposited some distance from the chainsaw. The characteristic striations created on the surface of wood as it is cut by a chainsaw can also be found on bony surfaces cut by a chainsaw.  相似文献   
213.
Spacepower is a critical element supporting the US national security strategy. As more nations gain access to technology, there is growing concern that space capabilities will be increasingly vulnerable to attack. However, a more insidious problem looms. For the last decade, the development and acquisition of US national security space systems have become more and more troubled with cost overruns and schedule delays. This grave situation has caught the attention of national security leadership and the US Congress. Panels of experts have proposed a litany of remedies. In this paper we explain and illustrate the importance of enhancing space power to better support national security needs and caution that many of the proposed acquisition solutions address symptoms, not the primary cause.

As history as shown…if the US offers an inviting target, it may well pay the price of attack. With the growing commercial and national security use of space, US assets in space and on the ground offer just such targets. The US is an attractive candidate for a ‘Space Pearl Harbor’. 1 Report of the Commission to Assess United States National Security Space Management and Organization, Pursuant to Public Law 106–65, January 11, 2001, available at <<http://www.defenselink.mil/pubs/space20010111.html>. This report is often referred to as the Space Commission Report.

This is the way the world ends

This is the way the world ends

This is the way the world ends

Not with a bang but a whimper. 2 T.S. Eliot, ‘The Hollow Men’, 1925.   相似文献   
214.
This study evaluated effects of the Iowa Strengthening Families Program, a family-focused universal preventive intervention, on growth patterns of adolescent internalizing (anxiety and depressive symptoms) and monthly polysubstance use (alcohol, tobacco, marijuana, inhalants, and other illicit drugs), as well as the association between internalizing and polysubstance growth factors. The sample consisted of rural Midwestern adolescents (N = 383), followed from sixth through twelfth grade. Compared to the control group, the intervention group adolescents showed a slower rate of increase in internalizing symptoms and polysubstance use. Intervention effects on internalizing symptoms were similar for boys and girls; however, girls demonstrated a higher overall level and a greater rate of increase across time. The intervention slowed the rate of increase in polysubstance use significantly more for girls than for boys, although overall levels of use were lower in the intervention group for both genders. Associations between internalizing and polysubstance use growth factors were found for girls, but not for boys, suggesting gender differences in psychosocial development.
Linda TrudeauEmail:
  相似文献   
215.
A survey of board-certified forensic pathologists (from a list of board-certified forensic pathologists supplied by the American Board of Pathology) was conducted to determine their current practice situations. The purpose of the survey was to provide information useful to the public in general and to those organizations that represent forensic pathologists in particular to better understand and meet the needs of the forensic pathology community. A total of 773 surveys were mailed, and 18 were returned as undeliverable. There were 337 replies (45%). Responses were as follows: In terms of age, 7% were in their 30s; 32% were in their 40s; 29% were in their 50s; 19% were in their 60s; and 13% were 70 years of age or older. In terms of gender, 79% were male and 21% were female. For pathology practice status, 72% worked more than 30 hours per week; 11% between 5 and 30 hours per week; 5% less than 5 hours per week; and 12% no longer practice pathology. For percentage of pathology practice that is forensic pathology, 69% of respondents were more than 80%; 6% were 50%-80%; 5% were 25%-50%; 8% were 5%-25%; and 12% were less than 5%. In terms of forensic pathology practice setting, 54% were employed by medical examiner or coroner systems; 13% worked under contract to medical examiner or coroner systems; 27% worked in private practice or consultation; and 6% responded as "other."  相似文献   
216.
Medical care should be safer. Inpatient problems and solutions have received the most attention; this outpatient qualitative case study addresses a gap in knowledge. We describe safety improvements among large physician groups, model the key influences on their behavior, and identify beneficial public and private policies. All groups were trying to reduce medical injury, which was part of the sample design. The most commonly targeted problems are those that are similar across groups: shortcomings in diagnosis, abnormal tests follow-up, scope of practice and referral patterns, and continuity of care. Medical group innovators vary greatly, however, in implementation of improvements, that is, in the extent to which they implement process changes that identify events/problems, analyze and track incidents, decide how to change clinical and administrative practices, and monitor impacts of the changes. Our conceptual model identifies key determinants: (1) demand for safety comes from external factors: legal, market, and professional; (2) organizational responses depend on internal factors: group size, scope, and integration; leadership and governance; professional culture; information-system assets; and financial and intellectual capital. Further, safety is an aspect of quality (the same tools, decision making, interventions, and monitoring apply), and safety management benefits from prior efficiency management (similar skills and culture of innovation). Observed variation in even simple safeguards shows that existing safety incentives are too weak. Our model suggests that the biggest improvement would come from boosting the demand for quality and safety from both private and public larger group purchasers. Current policy relies too much on litigation and discipline, which have sometimes helped, but not solved, problems because they are inefficient, tend to drive needed information underground, and complicate needed cultural change. Patients' safety demand is also weak for want of information and market power. Big purchasers' demands, however, quickly influence the internal environment of medical groups, helping managers advance quality safety toward the top of groups' congested decision-making "queues."  相似文献   
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218.
Nonconsensual insertion of a foreign object into the vagina, anus, or mouth in some judicial jurisdictions is synonymous with rape, and elsewhere may constitute some degree of sexual assault or battery. Few techniques, however, are available to assist the criminalist in determining whether an object has been criminally inserted. Glycogenated epithelial cells have been used as a marker for vaginal epithelium, and as such, may indicate vaginal insertion if recovered from an object. This hypothesis was tested by studying orally and vaginally inserted objects from 42 volunteers and 20 rectally inserted objects recovered from cadavers. Glycogen positivity was assayed from smears of object swabbings stained with the periodic acid-Schiff (PAS) technique. More than 75 glycogen positive cells were recovered from 39 of 42 vaginally inserted objects. Glycogenated cells were recovered from 8 of 20 rectally inserted objects (5 with more than 100 positive cells). Of 42 orally inserted objects, 32 also contained glycogen positive cells, but none with more than 28 positive cells. No glycogen positive cells were seen in skin exposed but not inserted objects. Large numbers of glycogen cells were seen in dried saliva drops. Amylase activity was not seen on 5 of 20 orally inserted shields, and thus the possibility of noninsertional saliva contamination could not be ruled out with shields yielding only small numbers of positive cells. Recovery of large numbers of glycogenated cells from foreign objects is strongly suggestive of either vaginal or anal insertion assuming amylase negativity. Glycogen positive cells are not seen secondary to glabrous skin exposure.  相似文献   
219.
220.
Major criticisms made by Chressanthis and Shaffer (C-S) are addressed: the authors' failure to include noneconomic variables in the regression model, the inclusion of open elections in the sample, and the use of variables other than the state unemployment rate as economic performance measures. Errors in C-S's interpretations are noted. Additional regression results are reported using modifications of the authors' original model. These suggest that the change (notrelative change as in C-S) in state unemployment rate is superior, and that the authors' model yields a stronger effect of state economic performance on election outcomes than does the C-S model.John Beck contributed helpful comments.  相似文献   
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