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Jamie M. Baerncopf B.S. Victoria L. McGuffin Ph.D. Ruth W. Smith Ph.D. 《Journal of forensic sciences》2011,56(1):70-81
Abstract: In fire debris analysis, weathering of ignitable liquids and matrix interferences can make the identification of ignitable liquid residues (ILRs) difficult. An objective method was developed to associate ILRs with the corresponding neat liquid with discrimination from matrix interferences using principal components analysis (PCA) and Pearson product moment correlation (PPMC) coefficients. Six ignitable liquids (gasoline, diesel, ultra pure paraffin lamp oil, adhesive remover, torch fuel, paint thinner) were spiked onto carpet, which was burned, then extracted using passive headspace extraction, and analyzed by gas chromatography‐mass spectrometry. Both light and heavy burn conditions were investigated. In the PCA scores plot, ignitable liquids were discriminated based on alkane and aromatic content. All ILRs were successfully associated with the corresponding neat liquid using both PCA and PPMC coefficients, regardless of the extent of burning. The method developed in this research may make the association of ILRs with corresponding neat liquids more objective. 相似文献
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Sweden is no longer a negative, exceptional case regarding the presence of radical right‐wing populist parties. The Sweden Democrats has continually grown stronger, and in 2010 they won seats in the Swedish parliament. However, their electoral support varies considerably across Sweden. This study analyses their electoral support in 290 Swedish municipalities in order to explain this variance. Support is found for the social marginality hypothesis: electoral support for the Sweden Democrats tends to be negatively correlated with the average level of education and with the Gross Regional Product per capita, and positively correlated with the unemployment rate. The ethnic competition hypothesis, that there is a positive correlation between the proportion of immigrants and electoral support of the Sweden Democrats, is also supported. 相似文献
397.
Analysis of impurities in seized MDMA tablets can be used to determine the synthesis method used and to identify links among exhibits. However, no standardized method exists to generate impurity profiles, limiting comparisons among different laboratories. This research investigated the effect of extraction procedure and gas chromatography temperature program on the resulting impurity profiles. Five exhibits were extracted using liquid–liquid extraction (LLE) and headspace solid‐phase microextraction (HS‐SPME), then analyzed using two different temperature programs. Profiles were statistically assessed using principal components analysis. While LLE was more reproducible, more compounds were extracted using HS‐SPME, thus providing more informative chemical profiles. The longer temperature program (53 min vs. 36 min) allowed greater discrimination of exhibits, due to improved precision as a result of an extended hold time (12 min). This research further highlights the need for standardized extraction and analysis procedures to allow comparison of chemical profiles generated in different laboratories. 相似文献
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Ruth Jackson 《Development in Practice》2014,24(3):339-352
This article explores three NGO projects that assemble and distribute clean birthing kits in Ethiopia. It contrasts the government's health strategy that aims to increase skilled birth attendance, with local realities as most women in rural and remote settings give birth at home, often in unhygienic conditions, and without skilled assistance. Many health facilities are also unable to provide hygienic conditions for birthing women. The findings indicate that clean birth kits have assisted the NGOs to effectively promote clean delivery at home or in health facilities, and to encourage antenatal care, and early referral to emergency obstetric and new-born care. 相似文献
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Hatcher RM McGuire J Bilby CA Palmer EJ Hollin CR 《International journal of offender therapy and comparative criminology》2012,56(3):447-464
Attrition from offender interventions presents methodological problems when the effectiveness of the intervention is under evaluation. This article proposes a treatment-received (TR) design, which incorporates one-to-one matching on criminogenic variables. This design permits the comparison of completer, noncompleter, and nonstarter groups with their paired comparisons and, hence, allows a more accurate evaluation of program completion and noncompletion effects. A sample of 173 offenders, referred to one of two general offending behavior cognitive skills programs within community settings, was matched one-to-one by criminogenic variables to offenders from an appropriate comparison group. Reconviction analyses were undertaken using intention to treat (ITT) analysis, TR analysis using the full comparison group, and TR analysis using matched comparison groups. The ITT design found no impact of group membership on reconviction. The TR designs, however, provided evidence of moderate effects of completion: For every three completers, five of the matched comparison group members were reconvicted. The analysis also suggested a noncompletion effect: Noncompleters were twice as likely as their matched comparison group to be reconvicted. 相似文献