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961.
Sheets HD Bush PJ Brzozowski C Nawrocki LA Ho P Bush MA 《Journal of forensic sciences》2011,56(3):621-626
Forensically identifying a suspect's dentition from a bitemark in an open population requires the supposition that every person's dental alignment is different. There have been few studies that have tested this claim. Four hundred and ten lower anterior dentitions from a selected population and 110 lower anterior dentitions from one that was orthodontically treated were measured using geometric morphometric analysis, allowing comparison of arch shape. Dental match rates of 1.46% and 42.7% of individuals were found in the respective populations, given an established measurement error. Orthodontic treatment had a strong effect on match rate suggesting that treated or naturally well-aligned dentitions may be indistinguishable. Sexual dimorphism was found to be only slightly significant. Principal shape variation in both populations was degree of arch curvature. Results of studying these populations show that dental matches can occur, and that statements of certainty concerning individualization in such populations should be approached with caution. 相似文献
962.
963.
Peter Van Ness 《现代国际关系(英文版)》2011,21(3):159-168
An arms race in space among the major powers would be immensely dangerous,destabilizing,and expensive.Russia,which has a long history in space technology dating back to Sputnik in 1957,does not have the resources or the political will to sustain such a race today.But China and the United States do. 相似文献
964.
Muennig P Sampat B Tilipman N Brown LD Glied SA 《Journal of health politics, policy and law》2011,36(5):829-853
The 2010 Patient Protection and Affordable Care Act (P.L. 111-148), or ACA, requires that U.S. citizens either purchase health insurance or pay a fine. To offset the financial burden for lower-income households, it also provides subsidies to ensure that health insurance premiums are affordable. However, relatively little work has been done on how such affordability standards should be set. The existing literature on affordability is not grounded in social norms and has methodological and theoretical flaws. To address these issues, we developed a series of hypothetical vignettes in which individual and household sociodemographic characteristics were varied. We then convened a panel of eighteen experts with extensive experience in affordability standards to evaluate the extent to which each vignette character could afford to pay for one of two health insurance plans. The panel varied with respect to political ideology and discipline. We find that there was considerable disagreement about how affordability is defined. There was also disagreement about what might be included in an affordability standard, with substantive debate surrounding whether savings, debt, education, or single parenthood is relevant. There was also substantial variation in experts' assessed affordability scores. Nevertheless, median expert affordability assessments were not far from those of ACA. 相似文献
965.
966.
Criticisms of the forensic discipline of bitemark analysis state that the range of distortion in the shape of bitemark impressions in skin has not been scientifically established. No systematic statistical studies exist that explore this problem. As a preliminary investigation of this issue, a single dentition was mounted in a mechanical apparatus and used to create 89 bitemarks in human cadaver skin, both parallel and perpendicular to tension lines. Impressions of the same dentition were also created in wax. 2D scanned images of the biting dentition were obtained. Locations of incisal edges of all 6 anterior teeth as well as the midpoint of the canine were captured as landmarks in all specimens. This set of landmark data was then studied using established geometric morphometric methods. All specimen shapes were compared using Procrustes superimposition methods, and by a variation of Procrustes superimposition which preserves scale information. Match criteria were established by examining the range of variation produced by repeated measurements of the dentition for each class of specimen. The bitemarks were also compared to a population of 411 digitally scanned dentitions, again using the match criteria. Results showed that bitemarks in wax had lower measurement error than scanned images of the dentition, and both were substantially lower than measurement error as recorded in skin. None of the 89 bitemarks matched the measured shape of the biting dentition or bitemarks in wax, within the repeated measurements error level, despite the fact that all bitemarks were produced by this dentition. Comparison of the bitemarks to the collection of 411 dentitions showed that the closest match to the bitemarks was not always the same dentition that produced the bitemarks. Examination of Procrustes plots of matched shapes showed non-overlapping distributions of measurements of bitemarks in skin, wax, and the dentition. All had statistically significant differences in mean shape. Principal component analysis (PCA) and canonical variates analysis (CVA) both showed clear segregation of the three types of data. The patterns of variance revealed by PCA showed several distinct patterns produced by skin distortion; alteration of relative arch width, and varying displacement of non-aligned teeth in the dentition. These initial results indicate that when multiple suspects possess similar dentitions, bitemark analysis should be approached with caution. 相似文献
967.
This article analyzes the impact of The Community Resources Group Receivership Program undertaken from 1998 to 2002 that provided clean property titles to residents in several informal housing colonias (subdivisions) in South Texas. Survey data were gathered from 260 low‐income households comprising two populations: those who had secure title from the outset, and those who were beneficiaries of the land titling program. Focus group interviews were conducted to explore how the beneficiaries construct the meaning of ownership before and after title “regularization.” Formal titling consolidates understandings of absolute property relations in comparison with de facto rights born of use (legal or not), which strengthens people's sense of self‐esteem and potential for political involvement. We found that, contrary to conventional wisdom, title provision per se appears to have little direct impact either upon home improvement or upon residents' receiving enhanced access to credit and financial services. We also found evidence that informality and illegality is likely to reemerge as owners die intestate, and as they revert to informal land market property transfers. 相似文献
968.
969.
The Latin American region is particularly prone to climate-related natural hazards. However, this article argues that natural hazards are only partly to blame for the region's vulnerability to natural disasters with quantitative evidence suggesting instead that income per capita and inequality are main determinants of natural disaster mortality in Latin America. Locally, the region's poor are particularly susceptible to climate-related natural hazards. As a result of their limited access to capital, adaptation based on social assets constitutes an effective coping strategy. Evidence from Bolivia and Belize illustrates the importance of social assets in protecting the most vulnerable against natural disasters. 相似文献
970.
Peter Knoepfel 《Swiss Political Science Review》2011,17(2):188-219
Abstract: The implementation of climate change adaptation polices has barely occurred in developed countries. This paper examines to what extent the perceptions of political actors might hinder the development of adaptation policies. We study the Swiss case using computer aided textual analysis. Our results demonstrate that adaptation is still not perceived as an important dimension of climate change policy. Decision makers do not perceive links between adaptation, the Swiss economy and the energy supply. Adaptation is mainly considered an issue for developing countries and not as a way to reduce the impacts of climate change in Switzerland. Right‐wing parties tend to consider adaptation a secondary issue and are more likely than those to the left to object to the formulation or the implementation of public measures. 相似文献