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991.
992.
993.
The conflicting outcome of the electoral and popular votes inthe 2000 presidential election provoked calls to abolish oralter the electoral college. One prominent criticism is thatthe institution distorts election outcomes by providing disproportionateinfluence to small states. If each state receives a number ofpresidential electors equal to that states' number of membersin the U.S. House of Representatives plus the two senators,then the "federalism bonus" represents the two electoral collegevotes that correspond to the position of each state as an equalentity in the Senate. This research examines how the "federalismbonus" influences presidential selection by addressing threequestions. First, why did the framers include a federal componentin the electoral college? Second, under what circumstances hasthe "federalism bonus" played a role in presidential selection?Third, how would the various alternatives for reform affectthe federal component of the electoral college, and what isthe likelihood of adoption for each? 相似文献
994.
马姝 《福建公安高等专科学校学报》2002,16(4):28-32
根据有组织犯罪的发展形态及特征 ,中国有组织犯罪按时间序列可分为三个阶段。作为观照社会问题的一类研究范式 ,“国家———社会”这一范式对于探讨有组织犯罪的演变及成因具有一定的意义。与中国有组织犯罪的不同发展时期相对应 ,国家与社会之间的关系发展呈现出不同的特点 ,而这些特点也是有组织犯罪形成与发展的重要原因。 相似文献
995.
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
996.
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
997.
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
998.
Comparing skeletal structures between antemortem and postmortem chest radiographs is widely used by forensic specialists from many disciplines to positively identify unknown decedents. However, validity assessments of this method have been fairly limited. This study had three objectives: 1) to quantify the reliability of ante- and postmortem chest radiograph comparison for decedent identification; 2) to identify useful radiologic features supporting decedent identification; and 3) to recognize sources of error in decedent identification related to use of comparative radiographs. A forensic pathologist, a forensic anthropologist, and two radiologists participated in the study. Our results showed that chest radiograph comparisons proved reliable, if basic decedent information was provided, and antemortem and postmortem radiographs were adequately positioned and exposed. A "morphological approach" using normal anatomical structures for comparison may provide the most efficient method for accurate identification. 相似文献
999.
Validation of a 16-locus fluorescent multiplex system 总被引:24,自引:0,他引:24
Krenke BE Tereba A Anderson SJ Buel E Culhane S Finis CJ Tomsey CS Zachetti JM Masibay A Rabbach DR Amiott EA Sprecher CJ 《Journal of forensic sciences》2002,47(4):773-785
STR multiplexes have been indispensable for the efficient genotyping of forensic samples. The PowerPlex 16 System contains the coreCODIS loci, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, CSF1PO, FGA, THOI, TPOX, vWA, the sex determinant locus, amelogenin, and two pentanucleotide STR loci, Penta D and Penta E. This multiplex satisfies the locus requirements for most national databases and is the most efficient currently available system due to its single PCR amplification. To provide the groundwork for judicial acceptance, including the publication of primer sequences, and to evaluate laboratory-to-laboratory variation, a developmental validation for casework on this commercially available system was performed in 24 laboratories and produced the following conclusions. Amplification was reliable on a variety of thermal cyclers and product could be analyzed on either an ABI PRISM 310 Genetic Analyzer or an ABI PRISM 377 DNA Sequencer. Genotyping using single source samples was consistent between 0.25 and 2 ng of input DNA template with a few laboratories obtaining complete genotypes at 0.0625 ng. However, heterozygote allele imbalance (<60% peak height balance) caused by stochastic effects was observed at a rate of 13% with 0.125 ng DNA and 22% at 0.0625 ng DNA. Mixture analyses were done using a total of 1 ng of DNA template. Most alleles were detected in mixtures of 4 to 1 and some minor alleles were detected in mixtures of 19 to 1. Optimum amplification cycle number was dependent on the sensitivity of the detection instrument used and could also be adjusted to accommodate larger amounts of DNA on solid supports such as FTA paper. Reaction conditions including volume, annealing temperature, and concentrations of primer, AmpliTaq Gold, and magnesium were shown to be optimal yet robust enough to withstand moderate variations without affecting genotype analysis. Environmental, matrix and standard source analyses revealed an ability to obtain complete genotypes in all sample types except those exposed to 80 degrees C for 12-48 days. Finally, comparison of genotype results from the PowerPlex 16 System with other commercially available systems on non-probative reference and forensic samples showed consistent results. 相似文献
1000.
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