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101.
Postmortem examination of a former professional basketball player revealed an abnormal heart, most notably a single coronary artery. The literature on single coronary arteries is briefly reviewed, and the possible mechanism which caused the patient's condition is considered. This case is particularly unusual because of the patient's profession, which is so physically demanding.  相似文献   
102.
This study used data from 299 police officers from 12 municipal police departments across the state of Virginia to determine the relationship between education and police performance. Performance was measured by supervisor evaluations of each officer's overall performance, communication skills, public relations skills, report writing skills, response to new training, decision making ability, and commitment to the police department. Significant correlations were found between education and most measures of performance. Most importantly, the results show a significant correlation between overall performance and education (r=24, p.<001). The only variables not proving to be significantly related to education were objective measures of the volume of arrests, number of times the officer required discipline, and number of accidents. Interestingly, the benefits of a college education do not become apparent until police officers gain experience. In addition, police, officers with only a high school diploma decreased in overall performance after five years of experience.  相似文献   
103.
The fingernail ridge patterns of a pair of identical twins were compared to each other, their parents, and an unrelated subject. The patterns of the twins' nails showed regions of strong similarity but were distinguishable from one another. Fewer similarities were found when comparing the nails to those of the parents and the unrelated control. The twins were shown to be monozygotic by means of DNA profiling. This therefore represents the first demonstration of unique fingernail ridge patterns in subjects shown conclusively to be identical twins. When the fingernail ridge patterns were examined with a scanning electron microscope, the backscattered electron (BEI) images were found to have superior contrast when compared to the secondary electron (SEI) images.  相似文献   
104.
105.
Although past research has developed scales for the incidence, prevalence, and fear of student-on-student victimization (SSV), little is known about the scaling of perceived risk (i.e., the cognitive appraisal of the chances of experiencing SSV). Hence, this study examined self-report survey data for the perceived risk of SSV as measured in the Adolescent Index for School Safety (AISS). Children in grades 7 through 10 (n=337) in a single Florida public school completed the AISS. Factor analyses using Maximum Likelihood Estimation with Oblimin Rotation identified nine unique factors for perceived risk. Reliability analyses found standardized Cronbach Alphas that ranged from .64 to .91, and seven out of the nine identified scales were above .80, which suggested good to excellent internal consistency. Future research should examine the content validity, construct validity, and predictive validity for the AISS and other self-report surveys of SSV dynamics. This publication was made possible by a grant [#97-MU-FX-KO12 (S-l)] from the Office of Juvenile Justice and Delinquency Prevention (O.J.J.D.P.), United States Department of Justice (U.S.D.O.J.). This grant is administered through the Hamilton Fish National Institute on School and Community Violence at George Washington University. This specific study was developed and implemented by staff at: 1) East Carolina University’s Department of Criminal Justice; and 2) Florida State University’s Center for Educational Research and Policy Studies. All points of view and opinions in this paper are those of the authors and do not necessarily represent the official position or policies of East Carolina University, Florida State University, the Hamilton Fish National Institute on School and Community Violence, the O.J.J.D.P., or the U.S.D.OJ. The authors would also like to thank Dr. Bill Doerner and Jennifer Jolley for their support, editorial feedback, and insightful comments regarding earlier drafts of this paper.  相似文献   
106.
This paper concerning the last 87 malpractice cases referred to the Department of Psychiatry and Law, Menninger Clinic, includes 57 suits against mental health practitioners and/or institutions, and 30 nonpsychiatric suits against general hospitals, surgeons, obstetricians, etc. A patient was available for interview in only 12 percent of the psychiatric cases; in 88 percent we reviewed medical records and consulted with attorneys. In the psychiatric cases the crucial question was whether a generally accepted standard of care was breached. The inherent problems of applying appropriate criteria to standards of care by practitioners and institutions are discussed. In half the psychiatric cases we found no significant deviation from acceptable clinical performance; in half we concluded that negligent practice had occurred. We did see a litigant for evaluation in 90 percent of the nonpsychiatric cases. The main issue involving them concerned harm or disability related to presumed negligence by medical personnel. How we evaluate such cases and apply disability criteria is discussed.  相似文献   
107.
In the current study the objective was to find to what extent a reliable determination of age at death is made possible by establishing the degree of aspartic acid racemization in the dentin of teeth. The results of the investigation of 46 teeth are in agreement with the values found by other authors. The method presented makes a reproducible and accurate estimation of age possible. We intend to elaborate and improve this promising method for determination of age at death. The relevant points are presented here.  相似文献   
108.
Quadratic pieces of fleece measuring 16 mm2 were soaked with 10 different blood-samples in the dilution steps of 1:1, 1:10, 1:100, 1:1000, respectively, and were tested in blood group typing and identification tests of forensic serology. The above spezified dilutions correspond with 5 microliters, 0.5 microliter, 0.05 microliter and 0.005 microliter of blood, respectively. The detection limit of the microspectrometric test for blood was the dilution 1:10, of the porphyrine test a dilution above 1:100, whereas the preliminary test for blood (peroxidase) succeeded always up to a dilution of 1:1000 and the species determination by the radial immunodiffusion test in agar gels succeeded in most cases op to a dilution of 1:1000. The detection limit of the anti-human globulin inhibition test was between the dilution steps 1:10 and 1:100 when non-titrated and undiluted anti-human globulin serum was used. Gc- and ABO-grouping were possible up to a dilution of 1:100 and were thus the most sensitive grouping systems. Phenotyping of the enzyme-systems and the Gm/Km-system usually required stains with considerably higher blood concentrations i.e. stains of undiluted blood.  相似文献   
109.
One of the remedies sought by state and local officials for the growing burden of federal mandates is a mandate reimbursement law. A major purpose of mandate reimbursement is to deter Congress from imposing excessive costs on state and local governments by making it fully accountable for its actions. The paper begins by extending the economic theory of grants to mandates and reimbursed mandates. It goes on to assess the benefits and costs of mandate reimbursement, and to distinguish mandates that should be reimbursed, should a reimbursement program prove desirable, from those that should not. Then, using the economic theory of grants and mandates, the paper compares reimbursed mandates with two alternatives for accomplishing the same objective, compensating grants and procedural rules. It concludes that the latter are more promising than mandate reimbursement.  相似文献   
110.
Telecommunications regulation has experienced a fundamentalshift from rate regulation to increased reliance on compelledaccess, perhaps best exemplified by the Telecommunications Actof 1996's imposition of no fewer than four new access requirements.Unfortunately, each access requirement is governed by a separateset of rules for determining both the scope and the price ofaccess. The resulting ad hoc regime has created difficult definitionalproblems and opportunities for regulatory arbitrage. In thisarticle we propose a system inspired by the discipline of mathematicsknown as graph theory that integrates all of the different formsof access into a single analytical framework. This system separatesdifferent access regimes into five categories: (1) retail access,(2) wholesale access, (3) interconnection access, (4) platformaccess, and (5) unbundled access. It also provides insightsinto how each type of access complicates the already difficultproblems of network configuration and management and introducesinefficient biases into decisions about network capacity anddesign. The approach we propose also provides insights intothe transaction cost implications of the different types ofaccess. Drawing on the Coasean theory of the firm, our approachexamines the tradeoffs between internal governance costs andthe external transaction costs of providing access to offera theory of network boundaries. This framework shows how accessregulation distorts networks' natural boundaries and providesa basis for evaluating whether private ordering through marketswould lead to more efficient network design.  相似文献   
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