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971.
972.
973.
Information sharing research has largely focused on capturing operational practices related to the exchange of information. A noticeable shortcoming of this developing literature is the lack of scholarly attention focused specifically on analytic personnel. The present study employs semi-structured interviews with 23 personnel that comprise the analytic unit within a regional fusion center located in a large metropolitan area in the United States. Findings indicate that there is significant ambiguity surrounding the organizational and geographic audiences to which intelligence products should be tailored. Moreover, it appears information sharing is sparse and reliant upon personal relationships between analysts and external organizations. Lastly, analysts do not receive feedback pertaining to the content and effectiveness of intelligence products created. These findings may be generalized to other analytical organizations whose primary goal is to gather, analyze and disseminate intelligence. Action steps for policymakers are provided.  相似文献   
974.
975.
This paper examines race-based peremptory challenges. Such challenges occur during the voir dire jury selection process. The process allows both the defense and the prosecution to strike jurors who they believe will not decide cases fairly. However, in the case of Batson v. Kentucky 476 U.S. 79 (1986), the Supreme Court ruled that race could not be used as a factor in eliminating prospective jurors. This paper examines federal litigation for five years in which it was alleged that race was used as a factor in removing a juror. An examination of the cases revealed that most of the cases involved sole male litigants who allege that there were multiple race-based peremptory challenges used in their cases. Moreover, most of the cases that led to the allegations involved violent offenses. Other case characteristics are noted, but of most significance was the finding that most appellants lost their cases. As such, the courts felt that most of the challenges were, in fact, race neutral. The implications of this research are discussed. This study was funded by an undergraduate research grant from Penn State University.  相似文献   
976.
This study evaluated the use of different degree day (DD) models, developmental thresholds and developmental data sources for estimating postmortem interval (PMI) based on developmental rates of blow flies (Diptera: Calliphoridae). Blow fly evidence was collected from three mock crime scenes and sent for blind analysis of PMI. PMI estimates were calculated using averaging, single sine, double sine, single triangle, and double triangle models of DD calculation with minimum developmental thresholds of 0, 6 and 10 °C and Anderson's, Byrd and Allen's, Greenberg's, Nishida's and Kamal's developmental data sets. These estimates were compared with the actual PMI to determine which combination of DD model, developmental threshold and developmental data provided the most accurate estimate. For all three cases, at least one method gave a PMI estimation that was within 1 day of the actual date of death. There was no variability between PMI estimated using the five models of DD calculation. Overall, as lower developmental threshold increased, the PMI interval estimates increased. Depending on the developmental data set used, increasing the lower developmental threshold caused some overestimations of the date of oviposition, with estimates given that were prior to the actual death. Future PMI estimates should include error ranges, so that overestimation of PMI is avoided.  相似文献   
977.
978.
Current forensic DNA profiling methods rely on the analysis of samples at specialised laboratories with an average turnaround time of several days. The ability to rapidly determine a partial profile of short tandem repeats at the point-of-arrest would be of great benefit to police forces around the world, for example enabling a suspect to be rapidly included or excluded from an investigation. We have developed a homogeneous PCR method for the interrogation of STR loci utilising fluorescent oligonucleotide probes and melting curve analysis. Alleles of the D18S51, TH01 and D8S1179 loci were differentiated and identified on the basis of target length and probe melting temperature. Assay performance was evaluated by comparing melting peak data with the AmpFlSTR® SGM Plus® system. The method is compatible with direct analysis of unpurified buccal swab samples, enabling a partial STR profile to be generated within 1 h.  相似文献   
979.
980.
Correlation among age, concentrations of carboxyhemoglobin and hydrogen cyanide, oxygen density and hemolysis were studied in 120 house fire victims. Victims aged over 60 years comprised approximately 50% of the pooled subjects. Blood samples were mainly collected from the left ventricle, but sometimes from both the right and left ventricles. The concentration of carboxyhemoglobin ranged from 1-95%, of which 71 persons (59.7%) died with carboxyhemoglobin concentrations below 60%. Carboxyhemoglobin concentrations below 10% were found in 9 persons (7.5%). Most of these cases involved the elderly persons. In this paper, we report on the death of elderly victims as a result of low carboxyhemoglobin concentrations. A significant correlation of blood carboxyhemoglobin concentrations existed between the right and left ventricles. The concentration of carboxyhemoglobin in the left ventricle was significantly higher than that in the right. Two out of 31 victims whose hydrogen cyanide concentrations were determined, succumbed to hydrogen cyanide poisoning, having a high concentration of hydrogen cyanide and a low concentration of carboxyhemoglobin. On analysis, oxygen density was found to be low in 13 persons. A negative correlation was shown between carboxyhemoglobin concentration and hemolysis. Inasmuch as hemolysis may indicate the extent of heat dissociation, hemolysis should provide an index of carbon monoxide dissociation from carboxyhemoglobin. In the present study of victims, possible causes of death i.e., carbon monoxide gas poisoning, hydrogen cyanide poisoning, oxygen deprivation, burning, shock due to burns and others were estimated. The survival time for elderly victims was considered to be short.  相似文献   
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