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941.
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
942.
943.
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
944.
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
945.
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
946.
947.
Soares-Vieira JA Billerbeck AE Pinto EM Iwamura ES Bilharinho de Mendonça B Otto PA 《The American journal of forensic medicine and pathology》2002,23(2):186-190
Gene and genotype frequencies in relation to the D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317, and D7S820 loci were determined in a sample of 290 unrelated individuals (204 Caucasians and 86 mulattoes) living in the city of S?o Paulo, Brazil. The sex test Amelogenin was also performed in all subjects from our sample, revealing the expected sex in all instances. Allele frequency data obtained from the analysis of these samples were in the usual range of other population groups with similar racial background. In the sample of Caucasian individuals, panmictic proportions were ruled out in relation to TPOX and CSF1PO loci, but only in the latter was the overall frequency of heterozygotes significantly less than expected. In the sample of mulattoes, Hardy-Weinberg proportions were rejected in relation to FGA and CSF1PO loci, but in no instance were the overall numbers of heterozygotes different from the corresponding expected ones under panmixia. Taking into account all this and also the number of tests performed, the degree of genetic heterogeneity of Brazilian populations, and the critical level reached by the significant results (1% < alpha<5%), the departures from panmixia here observed can be considered to be negligible in altering significantly biologic relationship odds calculated under the assumption of random matings. 相似文献
948.
It is argued that American courts may be routinely admitting evidence with little to no probative value and great potential for prejudicial impact. This may be particularly likely with regard to what is essentially intuitive profiling or stereotype related evidence, defined herein as evidence suggesting that the defendant (or other party), or his (her) behavior, fits intuitive profiles (or stereotypes) of the type of person likely to commit the crime or behavior in question. In other words, intuitive profiling evidence is admitted to postdict behavior. Formal empirically based profiling evidence (testimony regarding the fit of a defendant's characteristics or behaviors to formal or scientific profiles of the typical perpetrator of the crime in question for use to prove guilt is inadmissible in American courts. However, we suggest that everyday use of informal intuitive profiles underlies both judicial determinations of probative value diagnosticity, and thus admissibility, of evidence, and jurors' use of the evidence in determining guilt. Demonstrations of the use of base rate information to evaluate the probative value of such intuitive profiling evidence both as evidence of guilt and as evidence of innocence are provided. Demonstrations of both how to evaluate the actual probative value of evidence (when all necessary values are known), and the theoretical limit of its probative value (in circumstances where some values are not known) are provided. It is argued that such evaluations may provide the basis for (1) support of motions to either admit or to exclude evidence, (2) testimony to the jury to help them weigh or interpret evidence, (3) exculpatory profiling (profiling evidence of innocence), (4) pretrial research to establish probative versus prejudicial value of evidence, and (5) sufficiency analyses to determine maximum likelihood of guilt, given multiple items of evidence. Among these, the first two are considered most important, as it can be demonstrated that many profiling characteristics currently admitted in trial (such as evidence of battery to support a murder charge) are not probative of guilt. 相似文献
949.
950.
Sukhai A Harris C Moorad RG Dada MA 《The American journal of forensic medicine and pathology》2002,23(3):295-298
Self-immolation is an uncommon method of suicide, and its occurrence in South Africa is thus far unknown. This study aimed to determine the prevalence of self-immolation deaths and to establish a profile of these cases and the circumstances under which this condition occurs. A 5-year (1996-2000) retrospective review at a mortuary in Durban, South Africa, was conducted. Data were obtained from the Department of Forensic Medicine, the Medical Research Council's National Injury Mortality Surveillance System, and police and hospital records. During the study period, there were 12339 nonnatural deaths, of which 696 (5.6%) were suicides. Self-immolation accounted for 69 (0.6%) of all nonnatural deaths and 69 (9.9%) of all suicides. The subjects had a mean age of 31.2 years and were predominantly female (76.8%) and black (81.2%). The mean burn surface area was 63.3%, and the mean injury severity score was 36.9. Accelerant use was documented in 53 (76.8%) of cases, and paraffin was preferred. All cases occurred indoors. The proportion of suicides due to self-immolation in our study is excessive when compared with international studies that report figures between 0.9% and 2.2% of suicides. Additional studies are necessary to further elucidate the reasons for this discrepancy. 相似文献