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171.
Predicting the position of the source of blood stains for angled impacts   总被引:1,自引:0,他引:1  
Droplets of pig's blood were dropped onto paper at different angles to the horizontal to produce blood stains. Impact velocities varied from 1.82 to 5.76 m/sec, drop size from 3.7 to 5.0 mm in diameter, and the surface sloped at angles between 22.7 degrees and 90 degrees to the horizontal. From the data a single equation relating stain size to drop size and velocity for all impact angles was produced; ab = 111.74 (Re(1/2)We(1/4))(0.75)D(o)D(o) + 0.00084 with R(2) = 0.88, where a is the stain width, b the stain length, Re the Reynolds number, and We the Weber number. A second equation related the number of spines, N, to drop size, velocity, and surface slope for all impact angles as N = 0.76 We(0.5) sin(3)theta with R(2) = 0.9, where theta is the impact angle. Combining these equations the impact velocity can be determined and hence the position of the stain's source.  相似文献   
172.
The umbrella of employment-based health benefits is growing increasingly threadbare. As a result, health benefits are once again a major arena of labor-management strife, and once again calls for universal health care by many labor leaders mask important differences between them over health care reform. Some labor leaders advocate a bottom-up mobilization in support of a single-payer solution that would dismantle the system of job-based benefits rooted in private insurance. Others stake their health care strategy on wooing key business leaders to be constructive partners in some kind of unspecified comprehensive reform of the health system. Organized labor faces enormous obstacles, both institutional and ideological, to forging an effective united front to fight for comprehensive, high-quality, affordable health care for all. Two entrenched features of the shadow welfare state of job-based benefits, notably the Employee Retirement Income Security Act (ERISA) of 1974 and the union-run health and welfare funds created under the Taft-Hartley Act, remain daunting barriers on the road to reform, exacerbating tensions and differences within organized labor. Moreover, a dramatic ideological schism in the labor movement about its future direction vexes its stance on health care reform. These ideological differences fuel vastly different views within organized labor about how best to confront the unraveling of job-based health benefits and the growing popularity among business leaders, insurers, and public officials of the "individual-mandate" solution, which would penalize people who do not have adequate health insurance.  相似文献   
173.
Suspension is the most common form of discipline in our schools. In some cases students facing suspension are removed from school for an extended period of time or referred for expulsion based on the findings made at the student's suspension hearing. Nevertheless, students have no legal right to have counsel participate in, or advocate at, suspension hearings. Additionally, schools for the most part do not offer students alternatives to suspension, such as mediation sessions or other programs designed to allow students to complete school or community work while on suspension. This Note discusses the problems associated with school suspension and suspension hearings. It also explains why providing students with legal advocates at suspension hearings will help promote due process and facilitate better decision making on the part of the student. Finally, it advocates for mediation as an alternative to suspension and suspension hearings, as research suggests that mediation would reduce suspension rates and the costs associated therewith.  相似文献   
174.
The negotiations which led to the adoption of the International Criminal Court Statute in Rome in July 1998 owe much to non-governmental organisations' (NGOs) activism. These non-state actors developed professional skills enabling them to match state diplomats and experts. They developed particular strategies of mobilisation and thereby achieved a double goal: not only does the Rome Statute bear their mark but also their role is consecrated both within the text itself and in their relations with institutional actors. Although one has to nuance the scope of the participation of non-state actors in international negotiations and to balance it in the light of the interlocutors they have to face, this case study analyses the expertise gained by NGOs and their growing role in law-making processes.  相似文献   
175.
Coronary artery injury such as acute coronary dissection is an uncommon and potentially life‐threatening complication after blunt chest trauma. The authors report an unusual autopsy case of a 43‐year‐old healthy man who suddenly collapsed after receiving a punch to the chest during the practice of kung fu. The occurrence of the punch was supported by the presence of one recent contusion on the left lateral chest area at the external examination and by areas of hemorrhage next to the left lateral intercostal spaces at the internal examination. The histological examination revealed the presence of an acute dissection of the proximal segment of the left anterior descending coronary artery. Only few cases of coronary artery dissection have been reported due to trauma during sports activities such as rugby and soccer games, but never during the practice of martial arts, sports usually considered as safe and responsible for only minor trauma.  相似文献   
176.
Effects of benzodiazepines on postmortem opioid parent and parent/metabolite blood concentration ratios were determined for fentanyl‐, hydrocodone‐, methadone‐, or oxycodone‐related accidental deaths. These opioids are partially metabolized by the CYP3A4 enzyme system, which is also affected by diazepam and alprazolam. Opioid/metabolite combinations examined were as follows: fentanyl/norfentanyl, hydrocodone/dihydrocodeine, methadone/EDDP, and oxycodone/oxymorphone. Parent opioid concentrations were analyzed for 877 deaths. Parent/metabolite concentration ratios were analyzed for 349 deaths, excluding cases with co‐intoxicants present known to interfere with opioid elimination. Alprazolam in combination with diazepam significantly decreased median hydrocodone concentrations by 48% (p = 0.01) compared to hydrocodone alone. The methadone parent/metabolite concentration ratio was reduced by 35% in the presence of diazepam compared to methadone alone (p = 0.03). Benzodiazepines did not statistically significantly affect fentanyl or oxycodone concentrations. Possible factors affecting opioid concentrations and possible toxicity development, including any differential effects on specific opioids, should continue to be explored.  相似文献   
177.
Few studies have been conducted to determine sex differences in the immature coxal bone and the results were often contradictory. The authors studied sexual dimorphic differences of the pubis using geometric morphometric analysis of five osteometric landmarks recorded by multislice computed tomography (MSCT), based on three‐dimensional reconstructions of 188 children (95 boys, 93 girls) living in the region of Toulouse, southwestern France, ranging in age from 1 to 18 years old. They used geometric morphometric methodology first to test sexual dimorphism in size (centroid size) and shape (Procrustes residuals) and second to examine patterns of shape change with age (development) and size change with age (growth). Based on statistical significance test results, the pubic shape became sexually dimorphic at 13 years old, although visible shape differences were observed as early as 9 years old. This work showed that the trajectories of pubis shape (development) and size (growth) differed throughout ontogeny and between sexes.  相似文献   
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