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391.
Proença P Teixeira H Castanheira F Pinheiro J Monsanto PV Marques EP Vieira DN 《Forensic science international》2005,153(1):75-80
Imidacloprid [1-(6-chloro-3pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine] is a new and potent nitromethylene insecticide with high insecticidal activity at very low application rates. It is the first highly effective insecticide that, like nicotine, acts on the nervous system, causing blockage of postsynaptic nicotinergic acetylcholine receptors. Two fatal cases with this insecticide in two male individuals, of 33 and 66 years old, are presented. An LC/MS with electrospray method for measuring imidacloprid and its metabolites in post-mortem samples is described. In the chromatographic separation, a reverse-phase column XTerra MS C18 (2.1mm i.d.x 150 mm, 5 microm) was used and the mobile phase composed with acetonitrile and 0.1% formic acid (15:85), at a 0.25 mL/min flow rate. Samples were prepared with a liquid-liquid extraction procedure with dichloromethane. Calibration curves for imidacloprid in blood and urine samples were linear from 0.2 to 15 microg/mL. The mean recovery was 86% with a coefficient of variation of +/-5.9%. The detection limit was 0.002 microg/mL. Quantitative results were obtained for all post-mortem matrices available of the two fatal cases: blood, urine, stomach contents, lung, liver and kidney. The imidacloprid blood concentrations found in two-cases were 12.5 and 2.05 microg/mL. The authors validated a method to detect and quantify imidacloprid in post-mortem samples, and to our knowledge for the first time a post-mortem tissue distribution was performed on various samples for this insecticide. 相似文献
392.
Brion M Dupuy BM Heinrich M Hohoff C Hoste B Ludes B Mevag B Morling N Niederstätter H Parson W Sanchez J Bender K Siebert N Thacker C Vide C Carracedo A 《Forensic science international》2005,153(2-3):103-108
A collaborative study was carried out by the European DNA Profiling Group (EDNAP) in order to evaluate the performance of Y-chromosome binary polymorphism analysis in different European laboratories. Four blood samples were sent to the laboratories, to be analysed for 11 Y-chromosome single nucleotide polymorphisms (SNPs): SRY-1532, M40, M35, M213, M9, 92R7, M17, P25, M18, M153 and M167. All the labs were also asked to submit a population study including these markers. All participating laboratories reported the same results, indicating the reproducibility and robustness of Y-chromosome SNP typing. A total of 535 samples from six different European populations were also analysed. In Galicia (NW Spain) and Belgium, the most frequent haplogroup was R1b*(xR1b1,R1b3df). Haplogroup F*(xK) is one of the most frequent in Austria and Denmark, while the lowest frequency appear in Belgium. Haplogroup frequencies found in this collaborative study were compared with previously published European Y-chromosome haplogroup data. 相似文献
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395.
The present article tests predictions of rational political business cycle models using a large and previously unexplored data set of Portuguese municipalities. This data allows for a clean test of these predictions due to the high level of detail on expenditure items, an exogenous fixed election schedule, and homogeneity of Portuguese local governments with respect to policy instruments and institutions. Estimation results clearly reveal the opportunistic behaviour of local governments. In pre-electoral periods, they increase total expenditures and change their composition favouring items that are highly visible to the electorate. This behaviour is consistent with an effort to signal competence and increase chances of re-election. 相似文献
396.
How can policymakers reduce public fear of crime in Latin America? This study compares the effectiveness of “zero tolerance” and community‐based policing strategies in Argentina, Brazil, and Chile. At the micro level, it assesses the links between fear of crime and social identity characteristics, contextual factors, the media, community participation, and other insecurities. It finds that citizens' economic, political, and social insecurities are the main determinants of their fear of crime. At the macro level, the study compares levels of public insecurity and finds that cities that employ community‐based strategies to fight crime register lower levels of public fear of crime. 相似文献
397.
Allele and haplotype frequencies of 15 chromosome STR loci included in the kit PowerPlex16 System from Promega, were determined in a sample of unrelated males from Guiné-Bissau, a country from the west African coast. All individuals were subjected to an interview in order to make sure that their ancestors belonged to the same ethnic group. This way we intended to look for possible inter-ethnic differences. PowerPlex 16 includes STRs not studied before in any multi-ethnic population. The kit includes two new allele markers (Penta D and Penta E), which are very useful either in forensics or population genetic studies. The Guinean population presents significant differences when compared with other African populations. 相似文献
398.
Explaining Levels of Local Government Involvement in Service Delivery: The Dynamics of Cross‐Sector Partnerships in Malawi
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This study explores how local governments and their development partners—that is, donors, non‐governmental organisations and private companies—structure their partnerships as they work together to provide services to communities. Cases of collaboration between four organisations working in the rural water supply sector and six local governments in Malawi are studied. Using a cross‐case qualitative methodology, we illustrate how power and control translate into practices, leading to different levels of local government involvement in service delivery. This study contributes to the literature on cross‐sector partnerships in particular by developing empirically‐based propositions that help explain the dynamic trajectories that partnerships between local governments and their development partners can take. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
399.
Mélanie Loiseau MD Alice Matheux PharmD PhD Sandrine Sabini PharmD Stéphanie Cavard MD Anne-Sophie Advenier MD Agathe Pasquet Irène François-Purssell MD PhD Pascal Guerard MD PhD 《Journal of forensic sciences》2023,68(6):2200-2204
Nitrites are commonly used in the chemical, pharmaceutical, and food industries. Recently, they have been identified in cases of voluntary intoxication. We report the case of a 13-year-old girl who was found lifeless on her bed next to a glass containing a white powder and a bottle containing a white powder with a moistened appearance. External examination and autopsy revealed a nonspecific asphyxia syndrome, which was confirmed by the pathological analysis. Analysis of the samples revealed metoclopramide in the peripheral blood at a concentration of 0.402 mg/L (LC–HRMS). An analysis of the gastric contents was carried out after sodium nitrite was detected in the powders found near the body (Raman spectrometry). Nitrites were found in the gastric fluid at a concentration of 30.9 mg/L. Death occurred secondary to anoxia, following ingestion of nitrites; suicide kits are available on the web and nitrites are relatively easy to source and inexpensive. Nitrites are delivered in powder form to be dissolved in liquid, which may then be consumed with metoclopramide (or an alternative anti-emetic drug) to maximize absorption and reduce emesis. The toxic effect of nitrites lies in their oxidizing power, causing the transformation of hemoglobin into methemoglobin, which, when it accumulates, induces tissue anoxia resulting in death. There has been an alarming increase in the number of cases linked to suicide using nitrites or a nitrite suicide kit. The fact that nitrites are readily available online underscores the importance of establishing effective preventive measures such as limiting the access and use of this chemical. 相似文献
400.
Clément Martin MSc Marta Malević MSc Claire Diederich PhD François Verheggen PhD 《Journal of forensic sciences》2023,68(4):1190-1197
Human remains detection dogs (HRDD) are commonly used by law enforcement agencies to search for cadavers. Biological material is typically used as a training stimulus, also called aids, to train dogs to recognize the smell of cadavers. While HRDD training approaches have received extensive attention, information remains limited on the olfactory cues used to train them. Here, we aimed to decipher the chemical basis of detection dog olfaction. Five specific objectives were explored to precise whether the composition or the concentration of the training aids drives the HRDDs responses. We recorded the behavioral responses of four HRDDs exposed to different cadaveric-like smells. We found that HRDDs recognized a simplified synthetic aid composed of cadaveric compounds. The lowest concentration at which HRDDs continued to perceive the cadaveric smell was determined. HRDDs were not impacted by slight modifications to the chemical composition of a blend of odors that they have been trained with. HRDDs associated sulfur and nitrogen compounds as human cadaver. Our findings highlight a lack of specificity of HRDDs to cadaveric compounds, which could lead to error of detection. Moreover, all dogs did not positively respond to the same blends, despite being trained with the same aids and procedure. However, we confirmed that dogs could be trained with a simplified blend of molecules. The chemical composition of a training aid has, therefore, high consequences on the performance of the trained animal, and this conclusion opens additional questions regarding olfaction-based detection animals. 相似文献