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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   
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Laser desorption mass spectrometry (LDMS) may be used for the detection and identification of dyes found in inks. Naturally-aged and artificially-aged blue and black ballpoint pen inks containing the cationic dye methyl violet were analyzed on paper. The average molecular weight of the dye sample was calculated from LD mass spectral data and plotted versus time. The resulting aging curves demonstrate that, as dye degradation increases, the average molecular weight of the dye decreases. Typical variables involved in ink aging, such as the type of paper and ink formulation, were investigated. Results show that these variables influence the rate of dye degradation. Furthermore, UV accelerated aging has been developed and tested as an alternative to thermal approaches.  相似文献   
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This Article addresses the problems with our nation's cultural and legal prohibitions against certain pain management treatments. The practice of pain management has not kept pace with the many medical advances that have made it possible for physicians to ameliorate most pain. The Author notes that some patients are denied access to certain forms of treatments due to the mistaken belief that addiction may ensue. Additionally, some individuals are under-treated for their pain to a greater degree than are others. This is especially the case for our nation's prisoners. The Author contends that prisoners are frequently denied effective pain amelioration. He notes, however, that there has been improvement in medical treatment in general for prisoners due to court challenges based on the Eighth Amendment's prohibition against cruel and unusual punishment. Yet, due to the protection of qualified immunity given to jailers and prison health care providers, prisoners cannot bring a claim for negligence or medical malpractice, they must allege a violation of their constitutional rights, a significantly higher legal standard. Prisoners must meet a subjective test showing that there was a deliberate indifference to their medical needs that violates the protection of the Eighth Amendment. The Author concludes that because medical advances have made it possible to alleviate most pain suffering, withholding pain treatment or providing a less effective treatment is tantamount to inflicting pain and should be viewed as a violation of the Eighth Amendment.  相似文献   
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An ordnance-disposal expert was killed while disposing of a cache of explosives. The likely position of the body was reconstructed by modeling the explosion as an omnidirectional emission of particles from a model of the explosion site and noting the distribution of particles on a model of a human. The applications and limitations of this method in reconstructing the events and correlation with the injuries noted at autopsy are discussed.  相似文献   
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Salmonellae most commonly cause uncomplicated cases of gastroenteritis but have a predilection for damaged blood vessels, especially those damaged by atherosclerosis. The abdominal aorta is most frequently affected. The most serious complication of aortitis is mycotic aneurysm formation with subsequent rupture. The authors present the case of a 61-year-old man who was found unresponsive at home 3 days after discharge from the hospital for treatment of gastroenteritis with bacteremia. Postmortem examination revealed a ruptured mycotic aneurysm with a large retroperitoneal hematoma. Numerous gram-negative rods were embedded in the wall of the aorta and surrounding inflammatory infiltrate, compatible with the patient's previously isolated. Whereas abdominal aortic aneurysm rupture is most commonly associated with atherosclerosis, the isolation of from blood cultures, coupled with radiographic evidence of gas surrounding the aorta, should raise the suspicion of infectious aortitis. Whereas fatal rupture of an aortic aneurysm secondary to atherosclerosis alone or in conjunction with aortitis will not have an impact on the manner of death, infections are reportable and thus have public health implications.  相似文献   
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