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Arrow wounds represent an unusual class of wounds rarely seen by most death investigators. Although the edged, broadhead-tipped arrow produces a wound usually characteristic of archery/crossbow weapons, the plain, field-tipped arrow wound can be confused with gunshot injuries in those cases in which powder residue or firearm projectiles or fragments or both are not recovered. We present a case of a deer carcass with a wound of uncertain firearm or archery origin which initiated a comparison of firearm wounds and archery wounds on fresh road-killed deer. We found the following features to be valuable in the differentiation of gunshot wounds and field-tipped archery wounds: First, the majority of the gunshot wounds (but none of the arrow wounds) had identifiable, macroscopic, wipe-off material and chemically identifiable wipe-off residue by spot test. Second, the archery wound defects had very inconspicuous abrasion rings as compared to the often prominent abrasion rings of gunshot wounds. Third, the actual central defect in the archery wounds was more likely to be oblong or slit-like compared to the gunshot wound defects, which were more likely to be round.  相似文献   
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Vaginally inserted plastic tampon applicators were obtained from 42 female volunteers. The applicators were examined for the presence of ABH blood group substances, phosphoglucomutase (PGM), amylase, acid phosphatase, P30, and intact spermatozoa. Each applicator was accompanied by a control blood sample, a saliva specimen, a brief sexual and menstrual history, and method of birth control of the donor. Eight of the male sexual partners of the donors submitted blood and saliva samples. One male sexual partner submitted only a saliva sample. ABH blood group substances corresponding to the donor were recovered from 36 of the 42 applicators. The remaining 6 applicators revealed a combination of the donor's and sexual partner's ABH substances. The female's PGM type was recovered from 34 of the applicators. The remaining 8 applicators failed to show PGM activity. Of the applicators, 15 indicated evidence of prior sexual intercourse by the detection of ABH substances not consistent with the applicator donor (6 samples), high levels of acid phosphatase (11 samples), or recovery of spermatozoa (8 samples) or some combination of these. All applicator samples failed to show the presence of either P30 activity or PGM factors foreign to the female.  相似文献   
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A patent grants the holder a monopoly over the use of the patented invention for a specified time period. Although economists are generally opposed to monopoly, there seems to be a general consensus that the patent system is desirable.1 The rationale for the patent system is that without ownership rights in inventions, there would not be optimal allocation of resources to inventive activities, just as with any other valuable resource over which there are not well-defined property rights. However, the patent system, since it confers monopoly rights, has its drawbacks as well. If independent parties are working simultaneously toward an invention, the first to produce the invention will receive a monopoly over its use, even though others may have been only a month behind. This may encourage inventors to work too intensively toward a patent, and could also have the effect of producing monopoly in a market that was characterized by competition before the patent was issued. In addition, competitors have an incentive to develop substitute processes to avoid infringement of the patent, when the use of the patented process would be more economical. A substitute for patents which provides ownership rights in an invention without governmental grant of a monopoly is the trade secret. The purpose of this paper is to introduce and develop the idea of the law of trade secrets as a contractual alternative to patents.  相似文献   
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Intimate partner violence (IPV) is a crime that is present in all countries, seriously impacts victims, and demands a great deal of time and resources from the criminal justice system. The current study examined the use of the Spousal Assault Risk Assessment Guide, 2nd ed. (SARA; Kropp, Hart, Webster, & Eaves, 1995), a structured professional judgment risk assessment and management tool for IPV, by police officers in Sweden over a follow-up of 18 months. SARA risk assessments had significant predictive validity with respect to risk management recommendations made by police, as well as with recidivism as indexed by subsequent contacts with police. Risk management mediated the association between risk assessment and recidivism: High levels of intervention were associated with decreased recidivism in high risk cases, but with increased recidivism in low risk cases. The findings support the potential utility of police-based risk assessment and management of IPV, and in particular the belief that appropriately structured risk assessment and management decisions can prevent violence.  相似文献   
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Non-destructive identification and subsequent age estimation of blood stains are significant steps in forensic casework. The latter can provide important information on the temporal aspects of a crime. As previously shown, visible spectroscopy of blood stains on white backgrounds can successfully be used for their identification and age estimation. The use of this technique however, is hampered by dark backgrounds. In the present study the feasibility to use near infrared (NIR) spectroscopy was evaluated for blood stain identification and age estimation on dark backgrounds. Using NIR reflectance spectroscopy, blood stains were distinguished from other substances with 100% sensitivity and 100% specificity. In addition, Partial Least Squares Regression analysis was applied to estimate the age of blood stains on colored backgrounds. The age of blood stains up to 1 month old was estimated successfully with a root mean squared error of prediction of 8.9%. These findings are an important step toward the practical implementation of blood stain identification and age estimation in forensic casework, where a large variety of backgrounds can be encountered.  相似文献   
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