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271.
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With increasing frequency, relatively small, fragmentary evidence thought to be osseous or dental tissue of human origin is submitted to the forensic laboratory for DNA analysis with the request for positive identification. Prior to performing DNA analysis, however, it is prudent to first perform a presumptive test or "screen" to determine whether the questioned material may be eliminated from further consideration. When material is shown not to be consistent with bone/teeth, DNA testing is not performed. When such determinations cannot be made from gross morphological features, elemental analysis can be indicative. This presumptive test is made possible by applying scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) in conjunction with an X-ray spectral database recently developed by the FBI laboratory. This database includes spectra for many different materials including known examples of bone and tooth from many different contexts and representing the full range of taphonomic conditions. Results of SEM/EDS analysis of evidence can be compared to these standards to determine if they are consistent with bone and/or tooth and, if not, then what the material might represent. Analysis suggests that although the proportions and amounts of calcium and phosphorus are particularly important in differentiating bone and tooth from other materials, other minor differences in spectral profile can also provide significant discrimination. Analysis enables bone and tooth to be successfully distinguished from other materials in most cases. Exceptions appear to be ivory, mineral apatite, and perhaps some types of corals.  相似文献   
274.
Conclusions of 41 repeated expert evaluations of craniocerebral injuries within the framework of criminal and civil cases investigation are analyzed. Some aspects of clinical and forensic medical diagnosis of lethal and nonlethal injuries to the head, evaluation of the quality of medical care, and qualification of the severity of harm to health are discussed. Causes of typical expert errors and approaches to their prevention are shown.  相似文献   
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The primary aim of any DNA Database is to link individuals to unsolved offenses and unsolved offenses to each other via DNA profiling. This aim has been successfully realised during the operation of the New Zealand (NZ) DNA Databank over the past five years. The DNA Intelligence Project (DIP), a collaborative project involving NZ forensic and law enforcement agencies, interrogated the forensic case data held on the NZ DNA databank and collated it into a functional intelligence database. This database has been used to identify significant trends which direct Police and forensic personnel towards the most appropriate use of DNA technology. Intelligence is being provided in areas such as the level of usage of DNA techniques in criminal investigation, the relative success of crime scene samples and the geographical distribution of crimes. The DIP has broadened the dimensions of the information offered through the NZ DNA Databank and has furthered the understanding and investigative capability of both Police and forensic scientists. The outcomes of this research fit soundly with the current policies of 'intelligence led policing', which are being adopted by Police jurisdictions locally and overseas.  相似文献   
277.
In this study, we respond to calls for further investigation on why and how scientists choose to commercialize their research. Mowery (University entrepreneurship and technology transfer: process design, and intellectual property, Elsevier, Oxford 2005), in his criticism of the US-system, emphasizes the need for multiple channels between university and industry. His argument makes the case of Sweden interesting, where the researchers own the intellectual property of their research. Sweden thus constitutes a unique case where data can be found on which choices researchers make in a setting where a variety of channels for transfer are available. Our empirical data, collected through case studies, allowed for the expansion of the typology for mechanisms for transfer of academic research as well as the development of a typology for determinants for researchers’ choice to engage in transfer of research. Apart from those contributions to the theoretic discussion, the data also provided policy implications.  相似文献   
278.
The objective of this study was to determine the prevalence of physical and emotional abuse in Portuguese juvenile dating relationships and to investigate attitudes about these forms of violence. A sample of 4,667 participants, aged 13 to 29 years, completed two questionnaires, one behavioral and one attitudinal. At least one act of abuse perpetrated by a dating partner during the previous year was reported by 25.4% of participants (13.4% reported to have been victims of physical abuse and 19.5% of emotional abuse). Abuse of a partner was reported by 30.6% of participants; at least one act of physical abuse was reported by 18.1% and of emotional abuse by 22.4%. The attitudinal data revealed, however, a general disapproval of violence use. Violence support was higher among males, participants with lower educational and social status and those who had never been involved in a dating relationship. Women reported more acts of partner abuse than males; no gender differences were found regarding self-reported victimization. Both perpetration and victimization were reported more by older students. Although university students tend to report more acts of general and emotional abuse against their partners, students from professional schools are more represented among both perpetrators and victims of physical and severe violence. The best predictors of violence were educational status and attitudes toward partner.  相似文献   
279.
A new method for the detection of caffeine in blood has been proposed based on the combination of extraction and freezing-out to eliminate the influence of sample matrix. Metrological characteristics of the method are presented. Selectivity of detection is achieved by optimal conditions of analysis by high performance liquid chromatography. The method is technically simple and cost-efficient, it ensures rapid performance of the studies.  相似文献   
280.
Abstract:  We retrospectively reviewed autopsy records at a statewide medical examiner's office in order to identify and characterize deaths due to child abuse. In a 6-year period in New Mexico, the medical examiner investigated 45 deaths determined to be child abuse-related. Decedents were predominantly male (68.9%), Hispanic White (53.3%), and all were 5 years of age or younger, with a median age of 1 year. Head injuries were the most common cause of death (44.4%), followed by battered baby syndrome (15.6%). Relatives were involved as alleged perpetrators in 80% of the cases, with the father most often implicated (36.1% of cases), and 88.9% of child abuse injuries resulting in death occurred in the family's residence. Toxicology was positive in 26.7% of cases, but only two cases had substances of abuse present. Information on risk factors such as prematurity, parental age, and history of abuse was also collected.  相似文献   
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