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811.
H Brown D M Cauchi J L Holden F C Allen S Cordner P Thatcher 《Forensic science international》1999,100(3):179-186
A statistical investigation of the relationship between firing range and the amount and distribution of gunshot residue (GSR), used automated image analysis (IA) to quantify GSR deposit resulting from firings into pig skin, from distances ranging between contact and 45 cm. Overall, for a Ruger .22 semi-automatic rifle using CCI solid point, high velocity ammunition, the total area of GSR deposit on the skin sections decreased in a non-linear fashion with firing range. More specifically there were significant differences in the amount of GSR deposited from shots fired at contact compared with shots fired from distances between 2.5 and 45 cm; and between shots fired from a distance of 20 cm or less, with shots fired at a distance of 30 cm or more. In addition, GSR particles were heavily concentrated in the wound tract only for contact and close range shots at 2.5 cm, while the particle distribution was more uniform between the wound tract and the skin surfaces for shots fired from distances greater than 2.5 cm. Consequently, for future scientific investigations of gunshot fatalities, once standards have been established for the weapon and ammunition type in question, image analysis quantification of GSR deposited in and around the gunshot wound may be capable of providing a reliable, statistical basis for estimating firing range. 相似文献
812.
Wilkinson D 《Forensic science international》1999,99(1):5-23
This paper describes the development of a one-step fluorescent lipid reagent that involves europium chelates whose generic formula can be represented as europium(organic ligand)3.2(synergic reagent). An optimized formulation is presented and a comparison with physical developer was conducted which showed the new technique to be very good when fresh fingerprints were recovered but inferior to physical developer on aged prints (over a week). In addition, the compatibility of the technique with sequential methods such as ninhydrin and DFO is reported. The experimentation, results and chemical formulation of this study were presented to delegates of the International Symposium on Fingerprint Detection and Identification held in Israel in June 1995. Prior to that a patent application had been made. 相似文献
813.
Khokhlov VD 《Forensic science international》1999,104(2-3):147-162
The article presents the analysis of knitted trauma to the hyoid bone and laryngeal cartilages, revealed while searching for fresh fractures of the laryngopharynx skeleton for medico-legal purposes. Neck organocomplexes (n = 440) were completely prepared after fixation in formalin. Old injuries were found in 17.3% of cases, and in 3.2% of cases two elements of the complex were formerly broken. More often there was consolidated trauma to the thyroid (11.4% of cases) and cricoid cartilages (7.3%) and, rarely, to the hyoid bone (1.6%) and cervical part of the trachea (0.2%). These injuries occurred twice as often in men (20.3% of cases) than in women (P < 0.01). Substantiated conclusions are: (1) people of working age are most prone to neck trauma; and (2) from the 1960s the percentage of such traumas in the St. Petersburg region has grown due to urbanization. This article presents data on the localization and morphology of the injuries, as well as a review of symptoms and the course of blunt neck trauma. Despite the difficulties associated with the complete regeneration of injured tissues, forensic pathologists can obtain certain information which police officials may be interested in. 相似文献
814.
815.
816.
For mitigating climate change and adapting to whatever impacts we cannot avoid, there are no politically feasible alternatives to improvements in the U.S. Climate Change Action Plan at this time or for the foreseeable future. Yet improvements in the Action Plan have been obstructed by the diversion of attention and other resources to negotiating a binding international agreement, to developing a predictive understanding of global change, and to documenting the failure of the Action Plan to meet its short-term goal for the reduction of aggregate greenhouse gas emissions. Continuous improvements depend upon reallocating attention and other resources to the Action Plan, and more specifically, to the many small-scale policies that have already succeeded by climate change and no regrets criteria under the Action Plan. Sustaining the effort over the long term depends on harvesting experience from these small-scale successes for diffusion and adaptation elsewhere on a voluntary basis. 相似文献
817.
818.
"This article compares two sources of data on Mexico-U.S. migration, based on radically different methodologies: the Mexican Migration Project (Promig) and the National Survey of Population Dynamics (Enadid).... This comparative study shows that a micro-social design drawing on multiple community samples, such as Promig, can solve the methodological conflict between specificity and representativeness.... The authors' research also highlights the problem of selectivity and specificity entailed by traditional surveys such as Enadid as a result of restricting their samples to international residents in Mexico and attempting to explain such a complex, socioeconomic process using a limited number of variables." (EXCERPT) 相似文献
819.
Delaunay D 《Estudios demográficos y urbanos》1999,14(1):117-63, 263
"Although Mexican migration to the United States dates back over a century, reliable statistics documenting its geographical distribution have only recently become available. This new information, together with the creation of a Geographical Data System and the recent development of multilevel analysis, have allowed one to examine the regional context of Mexican migration to the U.S.... This paper draws on two new tools for context analysis and examines how they can be used to study international migration: first, the Geographical Data systems, which measure physical factors (aridity, isolation, land use, environmental degradation), together with socioeconomic statistics and familial organization and reproduction." (EXCERPT) 相似文献
820.
In 1991 and 1992, the City of Eugene, Oregon engaged in a citizen participation process to determine public support for a variety of spending and budget balancing alternatives. This process, called Eugene Decisions, employed an innovative combination of public forums, budget balancing exercises and representative surveys. Two of the surveys, which included questions about individual service use, are analyzed here in order to test whether the use of city services is related to willingness to pay taxes and fees. The concept of benefit equity is supported if service use is positively associated with willingness to pay. 相似文献