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941.
The climate of school classrooms, shaped by a combination of teacher practices and peer processes, is an important determinant for children's psychosocial functioning and is a primary factor affecting bullying and victimization. Given that there are relatively few theoretically-grounded and validated assessment tools designed to measure the social climate of classrooms, our research team developed an observation tool through participatory action research (PAR). This article details how the assessment tool was designed and preliminarily validated in 18 third-, fourth-, and fifth-grade classrooms in a large urban public school district. The goals of this study are to illustrate the feasibility of a PAR paradigm in measurement development, ascertain the psychometric properties of the assessment tool, and determine associations with different indices of classroom levels of relational and physical aggression.  相似文献   
942.
Despite ample evidence of preelection volatility in vote intentions in new democracies, scholars of comparative politics remain skeptical that campaigns affect election outcomes. Research on the United States provides a theoretical rationale for campaign effects, but shows little of it in practice in presidential elections because candidates’ media investments are about equal and voters’ accumulated political knowledge and partisan attachments make them resistant to persuasive messages. I vary these parameters by examining a new democracy where voters’ weaker partisan attachments and lower levels of political information magnify the effects of candidates’ asymmetric media investments to create large persuasion effects. The findings have implications for the generalizability of campaign effects theory to new democracies, the development of mass partisanship, candidate advertising strategies, and the specific outcome of Mexico's hotly contested 2006 presidential election. Data come primarily from the Mexico 2006 Panel Study.  相似文献   
943.
This article uses data from the 2008 Cooperative Congressional Election Study to explain weak support for public financing of congressional campaigns. Previous studies lack theory to explain variation in support and use a flawed measure of the dependent variable. We argue that low support reflects a failure resulting from a collective action dilemma. Citizens desire a campaign finance system that weans politicians from private donors, but are unwilling to pay a small amount in taxes to support public financing. In contrast to conventional wisdom, we show that support for public financing is highest among those perceived to benefit the most from the current system. Our results suggest that most Americans would rather not pay for politics, and that reform proposals must avoid incurring transparent costs on individual citizens to pay for reform.  相似文献   
944.
For a single-winner multi-candidate election, it is broadly accepted that the Condorcet candidate (if one exists) should win. Voting systems do not always elect the Condorcet winner. Public opinion polls are not generally designed to try to identify a Condorcet candidate. They could easily be constructed to do so, however. The resulting process may be called Condorcet polling, for which various designs are presented herein. Information from Condorcet polling may enable some voters, under a plurality or runoff system, to bring about an outcome they prefer by voting strategically for the Condorcet candidate when they would not otherwise do so.  相似文献   
945.
946.
3'-Hydroxystanosolol detection in biological fluids at pg levels by gas chromatography/tandem mass spectrometry is described. Gas chromatography/high resolution mass spectrometry results can be confirmed with gas chromatography/tandem mass-spectrometry.  相似文献   
947.
Superwarfarin exposure is a growing health problem, described in many countries. The authors report a case of suspicious chlorophacinone poisoning with a problematic diagnosis. They review the literature and discuss particularities of anticoagulant rodenticide intoxication, as well as the apparent contradiction between anticoagulant intoxication and lethal thrombosis.  相似文献   
948.
Organised criminality is a great concern for national/international security. The demonstration of complex crimes is increasingly dependant on knowledge distributed within law-enforcement agencies and scientific disciplines. This separation of knowledge creates difficulties in reconstructing and prosecuting such crimes. Basic interdisciplinary research in drug intelligence combined with crime analysis, forensic intelligence, and traditional law enforcement investigation is leading to important advances in crime investigation support. Laboratory results constitute one highly dependable source of information that is both reliable and testable. Their operational use can support investigation and even provide undetected connections or organisation of structure. The foremost difficulties encountered by drug analysts are not principally of a chemical or analytical nature, but methodologies to extract parameters or features that are deemed to be crucial for handling and contextualising drug profiling data. An organised memory has been developed in order to provide accurate, timely, useful and meaningful information for linking spatially and temporally distinct events on a national and international level (including cross-border phenomena). Literature has already pointed out that forensic case data are amenable for use in an intelligence perspective if data and knowledge of specialised actors are appropriately organised, shared and processed. As a particular form of forensic case data, the authors' research focuses on parameters obtained through the systematic physical and chemical profiling of samples of illicit drugs. The procedure is used to infer and characterise links between samples that originate from the same and different seizures. The discussion will not, however, focus on how samples are actually analysed and compared as substantial literature on this topic already exists. Rather, attention is primarily drawn to an active and close collaboration between magistrates, forensic scientists, law enforcement investigators and crime analysts from different institutions with the aim of generating, using and validating relevant profiling case data as integral part of investigative and crime analysis processes. Original advances are highlighted through experiences from criminal investigations of offences related to the unlawful importation, exportation, supply and possession of illicit drugs.  相似文献   
949.
Even though trace evidence is becoming more and more important in legal cases, only little is known about the influence of task and context factors on comparative judgments. In the present study we investigated how expectations and complexity affect shoe print examinations and to what extent differences exist between beginners and experienced examiners. Twelve examiners assessed similarity between a shoe print and a shoe for eight different cases. For half the cases expectation was induced by providing additional incriminating evidence. A complex case meant that the print was relatively noisy, for example because the perpetrator rotated his foot. A simple case meant that the print was clear. The results showed that there was no effect of expectation and no effect of experience. Only complexity affected the examiners' assessments: when the background was noisy, the acquired features received a lower evidential value than when the background was clear. Apparently, examiners compensated for the quality of the print and were more cautious in drawing conclusions when prints were less clear. Even though the results allow for some optimism with regard to the influence of expectations on shoe print examinations, it has to be taken into account that the Dutch procedure is supported by a formal guideline, which may (partly) explain the present findings.  相似文献   
950.
Optimisation and harmonisation of analytical and statistical methodology have been carried out between two forensic laboratories (Lausanne, CH and Lyon, F) in order to provide drug intelligence for cross-border cocaine seizures. The aim was to improve the gas chromatographic analysis of cocaine samples for profiling. Some important validation parameters were tested to verify the developed method and demonstrate its profiling capacity: the selectivity of the method with retention time reproducibility, the choice of a derivatisation agent improving the chromatography (MSTFA, BSA, TMSI and BSTFA+TMCS 1%), the cutting agents influence (matrix effect), the influence of the sample storage conditions and the sample quantity to weigh for analyses. Eight main alkaloids, which represent the sample signature, have been selected: ecgonine methyl ester, ecgonine, tropacocaine, benzoylecgonine, norcocaine, cis- and trans-cinnamoylcocaine and 3,4,5-trimethoxycocaine. Their stability in the solvent used (CHCl(3)/pyridine) was demonstrated. In order to reach the final objective, which is the comparison of samples seized and analyzed in two different laboratories, the harmonisation of the profiling method between the two laboratories had to be ensured and is the subject of ongoing research.  相似文献   
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