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991.
A collaborative study on Raman spectroscopy and microspectrophotometry (MSP) was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on different dyed cotton fabrics. The detection limits of the two methods were tested on two cotton sets with a dye concentration ranging from 0.5 to 0.005% (w/w). This survey shows that it is possible to detect the presence of dye in fibres with concentrations below that detectable by the traditional methods of light microscopy and microspectrophotometry (MSP). The MSP detection limit for the dyes used in this study was found to be a concentration of 0.5% (w/w). At this concentration, the fibres appear colourless with light microscopy. Raman spectroscopy clearly shows a higher potential to detect concentrations of dyes as low as 0.05% for the yellow dye RY145 and 0.005% for the blue dye RB221. This detection limit was found to depend both on the chemical composition of the dye itself and on the analytical conditions, particularly the laser wavelength. Furthermore, analysis of binary mixtures of dyes showed that while the minor dye was detected at 1.5% (w/w) (30% of the total dye concentration) using microspectrophotometry, it was detected at a level as low as 0.05% (w/w) (10% of the total dye concentration) using Raman spectroscopy. This work also highlights the importance of a flexible Raman instrument equipped with several lasers at different wavelengths for the analysis of dyed fibres. The operator and the set up of the analytical conditions are also of prime importance in order to obtain high quality spectra. Changing the laser wavelength is important to detect different dyes in a mixture.  相似文献   
992.
Serious head and neck injuries are a common finding in fatalities associated with rollover crashes. In some fatal rollover crashes, particularly when ejection occurs, the determination of which occupant was driving at the time of the crash may be uncertain. In the present investigation, we describe the analysis of rollover crash data from the National Automotive Sampling System-Crashworthiness Data System for the years 1997 through 2007 in which we examined the relationship between a serious head and neck injury in an occupant and a specified degree of roof deformation at the occupant's seating position. We found 960 occupants who qualified for the analysis, with 142 deaths among the subjects. Using a ranked composite head and neck injury score (the HNISS) we found a strong relationship between HNISS and the degree of roof crush. As a result of the analysis, we arrived at a predictive model, in which each additional unit increase in HNISS equated to an increased odds of roof crush as follows: for ≥8cm of roof crush compared with <8cm by 4%, for ≥15cm of roof crush compared to <8cm by 6% and for ≥30cm of roof crush compared to <8cm by 11%. We describe two hypothetical scenarios in which the model could be applied to the real world investigation of occupant position in a rollover crash-related fatality.  相似文献   
993.
Spatial and Temporal Patterns of Terrorist Attacks by ETA 1970 to 2007   总被引:3,自引:0,他引:3  
Rational choice perspectives maintain that seemingly irrational behavior on the part of terrorist organizations may nevertheless reflect strategic planning. In this paper we examine spatial and temporal patterns of terrorist attacks by the Spanish group ETA between 1970 and 2007. Our analysis is guided by a public announcement by ETA in 1978 that the group would shift from emphasizing attacks in the Basque territory to instead launch attacks more widely in the hopes of exhausting the Spanish government and forcing it to abandon the Basque territory. This announcement suggests that prior to the end of 1978 ETA attacks were based mostly on controlling territory in the Basque region that they hoped to rule; and after 1978 the organization decided to instead undertake a prolonged war of attrition. Accordingly, we argue that before the end of 1978 ETA was mostly perpetrating control attacks (attacking only within the Basque territories) and that the diffusion of attacks between provinces was mostly contagious (spreading contiguously). After the 1978 proclamation, we argue that the attack strategy shifted toward attrition (attacking in areas outside of the Basque territories) and that the attacks were more likely to diffuse hierarchically (spreading to more distant locations). As predicted, we find that after ETA moved toward a more attrition based attack strategy, subsequent attacks were significantly more likely to occur outside the Basque region and to target non-adjacent regions (consistent with hierarchical diffusion). We also find that hierarchical diffusion was more common when a longer time elapsed between attacks (a likely consequence of the fact that more distant attacks require more resources and planning) and that attacks against Madrid were unlikely to be followed immediately by more attacks on Madrid or surrounding provinces. After ETA announced a shift in policy, they maintained a highly dispersed attack strategy even during their period of decline. Using information about where and when prior attacks occurred could provide useful information for policy makers countering groups like ETA.  相似文献   
994.
In this study, we examine citizens?? perceptions of police?Ccommunity relationships in India. More specifically, in this exploratory study, we examine the extent to which factors such as general satisfaction with police services, police professionalism, feeling of safety, and perception of police integrity all explain the public confidence in police?Ccitizen relationships. Those who are generally satisfied with police like to work with police and view police?Ccommunity relationships positively. Further, we find that those who feel police are fair in dealing with citizens, irrespective of social status, and those who feel more safe in their communities are those who are most willing to work with police.  相似文献   
995.
New data show that between 1982 and 2007, in over 60 countries governments were linked to and cooperated with informal armed groups within their own borders. Given the prevalence of these linkages, we ask how such links between governments and informal armed groups influence the risk of repression. We draw on principal-agent arguments to explore how issues of monitoring and control help understanding of the impact of militias on human rights violations. We argue that such informal agents increase accountability problems for the governments, which is likely to worsen human rights conditions for two reasons. First, it is more difficult for governments to control and to train these militias, and they may have private interests in the use of violence. Second, informal armed groups allow governments to shift responsibility and use repression for strategic benefits while evading accountability. Using a global dataset from 1982 to 2007, we show that pro-government militias increase the risk of repression and that the presence of militias also affects the type of violations that we observe.  相似文献   
996.
When and how will personal financial (aka “pocketbook”) concerns drive citizens’ political decisions? Scholars remain puzzled by the mismatch between the expectation that pocketbook voting should occur and the reality that, according to most findings, it usually does not. Using original survey data collected immediately after Iceland’s second “Icesave” referendum (2011), I first report the results of an embedded experiment that successfully evokes greater pocketbook concern. Next, I analyze the determinants of retrospective pocketbook evaluations, showing that priming effects are conditioned by political sophistication such that high sophisticates are among the most likely to report negative economic assessments. I then turn to the consequences of these egocentric views for government approval. Mediation analysis confirms a significant indirect effect, suggesting that subjective pocketbook evaluations exert a strong influence on political attitudes that has been hidden in prior work. Results illuminate the contextual, cognitive, and causal circumstances under which pocketbook effects transpire and suggest new ways in which self-interest might matter for attitudes toward international political economy issues.  相似文献   
997.
Conventional wisdom suggests that dissident groups use terrorism when they face an overwhelmingly more powerful state, yet attacks in developing countries have predominated in the post-Cold War era, suggesting that terrorism is an increasingly weak state phenomenon. Cross-national studies of terrorism find mixed results for how common measures of state capacity influence terrorism. We argue that these indeterminate findings are due in part to a partial understanding of both what constitutes state capacity and how different aspects of state strength or weakness relate to the propensity of groups to use terrorism. We decompose state capacity into two dimensions that we theorize are particularly relevant to dissident groups: military capacity, or the ability to project conventional military force, and bureaucratic/administrative capacity. Our analysis supports the claim that terrorist attacks are more frequently targeted at states with large, technologically sophisticated militaries but less frequently targeted at states with higher bureaucratic and administrative capacity. We also compare two militarily capable states, France and Russia, that have had different recent experiences with terrorism to help illustrate the causal mechanisms involved. Evidence from our models and cases suggest that states can be capable in different ways, and these various capabilities create differing incentives for using terror as a strategic and tactical tool.  相似文献   
998.
This paper argues that religion influences the ways that people think and speak about corruption, typically leading to condemnation. However, it is also argued that, in a systemically corrupt country, such condemnation is unlikely to influence actual corrupt behaviour. Based on fieldwork in India, the paper finds that existing anti-corruption policies based on a principal-agent understanding of corruption, even if they incorporate religious organisations and leaders, are unlikely to work, partly because people consider “religion” to be a discredited entity. Instead, the paper argues that if corruption were to be seen as a collective action problem, anti-corruption practice would need significant rethinking. Despite its current lack of influence, revised policies and practices may see a role for religion.  相似文献   
999.
The quantity of mitochondrial DNA (mtDNA) template added for amplification and subsequent dye terminator reactions is critical for obtaining quality sequence data. Validation of a human mtDNA real‐time quantitative PCR (qPCR) assay demonstrated its high degree of reproducibility and precision as well as an extremely sensitive threshold of detection (0.0001 pg/μL or approximately six human mtDNA copies/μL). A study of 35 nonprobative bone and teeth evidence samples revealed that 20 pg of mtDNA template is recommended for successful HV1 and HV2 sequence analysis; however, as little as 0.013 pg can generate a full mtDNA profile when using enhanced amplification reactions. The assay can also detect PCR inhibition and is useful for identifying samples that may benefit from re‐purification. Overall, the assay is an excellent method to quantify mtDNA and is useful for determining the best analytical approach for successful sequencing.  相似文献   
1000.
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