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901.
Lawrence Veysey 《Society》1988,25(2):58-61
He is retired and lives in Hawaii. 相似文献
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East Asian governments have engaged in unprecedented collaborationon trade and financial matters since the economic crises of1997. For some observers, such activity, building on a new senseof shared identity forged by resentment at Western responsesto the crises, is a significant step towards the formation ofan East Asian economic bloc. In reality, the new collaborationhas produced only modest results. Neither an East Asian preferentialtrade agreement nor an Asian Monetary Fund is likely to materialize.Underlying power realities and fundamental economic interestsare unchanged. The new interest in negotiating preferentialtrade agreements (many of which are with countries outside ofEast Asia) is best explained by government perceptions of theeffectiveness of such arrangements elsewhere in the global economy,and by a desire to increase bargaining power. 相似文献
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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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Evaluation of laser desorption mass spectrometry and UV accelerated aging of dyes on paper as tools for the evaluation of a questioned document 总被引:1,自引:0,他引:1
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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Mitochondrial DNA (mtDNA) analysis of forensic samples typically is performed when the quantity and quality of DNA are insufficient for nuclear DNA analysis or when maternal relatives may be the only reference source. Many of the steps required in the analytical process are both lengthy and labor intensive. Therefore, improvements in the process that reduce labor without compromising the quality of the data are desirable. The current procedure requires purification of the amplicons by centrifugal filtration after PCR and prior to cycle sequencing. Because this method requires several manipulations to perform, alternate cleanup procedures were investigated. These include the use of 1) Qiagen QlAquick PCR Purification columns, 2) Concert Rapid PCR Purification columns, and 3) ExoSAP-IT reagent. When the yield of purified amplicons, quality of the sequence profile, and ease of assay were evaluated, the use of ExoSAP-IT reagent for post-amplification purification was chosen to replace the filtration method. 相似文献
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A study of 30 cases of violence from a total sample of 199 cases of infant abductions between the years 1983 and 2000 included a subsample of six (or 20%) where the kidnapping was by cesarean section. The six cases are classified by type of crime. Four cases were classified as personal cause homicide, subtype cesarean section homicide; one case classified as personal cause, subtype domestic homicide, and one case classified as a criminal enterprise homicide. The behavioral profiles of the abductors included a confidence style approach to the victim mother, deception, and planning of the cesarean section. The forensic psychodynamics suggest a dual motive to cement a failing partner relationship and to fulfill a childbearing and delivery fantasy. Cesarean section murder suggests a new category of personal cause homicide. 相似文献
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