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1.
Are internalizing and externalizing behavior problems interrelated via mutually reinforcing relationships (with each behavior leading to increases over time in levels of the other behavior) or mutually suppressing relationships (with each behavior leading to decreases over time in levels of the other behavior)? Past research on the directionality of these relationships has led to ambiguous results, particularly in adolescence. Furthermore, the extent to which prior results will generalize to adolescents with low levels of cognitive abilities remains unknown. This second limit is particularly important, given that these adolescents are known to present higher levels of externalizing and internalizing behaviors than their peers with average-to-high levels of cognitive abilities, and that the mechanisms involved in the reciprocal relationships between these two types of behaviors may differ across both populations. This study examines the directionality of the longitudinal relationships between externalizing and internalizing behavior problems as rated by teachers across three measurement waves (corresponding to Grades 8–10) in matched samples of 138 adolescents (34.78?% girls) with low levels of cognitive abilities and 556 adolescents (44.88?% girls) with average-to-high levels of cognitive abilities. The results showed that the measurement structure was fully equivalent across time periods and groups of adolescents, revealing high levels of developmental stability in both types of problems, and moderately high levels of cross-sectional associations. Levels of both internalizing and externalizing behaviors were higher among adolescents with low levels of cognitive abilities relative to those with average-to-high levels of cognitive abilities. Finally, the predictive analyses revealed negative reciprocal longitudinal relationships (i.e., mutually suppressing relationships) between externalizing and internalizing problems, a result that was replicated within samples of adolescents with low, and average-to-high levels of cognitive ability.  相似文献   
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The success or failure of international peacebuilding missions is predominantly evaluated in reference to interveners’ ability to exercise their mandated authorities. To test the value of an empirically based analysis of authority-building processes in the course of such missions the article turns to the United Nations Transitional Authority in Cambodia (UNTAC, 1992–1993). In order to safeguard the country’s stability many supported the idea of holding presidential elections in addition to the ones for the Constituent Assembly forming the new government. To organize such unforeseen elections UNTAC would have had to change its mandate as determined by the Paris Peace Accords (PPA). Based on extensive archival research the paper analyses the debate surrounding this proposal as a series of legitimacy claims that were selectively recognized and rejected. The article concludes that evaluations of peacebuilding missions are indeed too focused on interveners’ authority to decide, while neglecting or underestimating challenges to their authority to interpret. This fosters a false sense of control over the direction of political processes.  相似文献   
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Current procedures for human DNA quantitation reach their limit at 150 pg DNA, which is above the limit of the PCR profiling range using Profiler-Plus (Applied Biosystems, CA). This study tested the potential for the use of primate specific Alu sequences in forensic science for the sensitive detection and quantitaion of DNA. A fluorescently labelled primer pair was designed enabling high efficiency amplification of the core Alu sequence within primate DNA. Quantitation was performed by measurement of fluorescence intensity and comparison to a series of standard template DNA amounts via the construction of a standard curve. The new Alu-based quantitation protocol developed has shown its feasibility in more sensitively quantitating (100-2.5 pg) unknown amounts of human DNA for forensic use. The method is compatible with the use and throughput of current forensic procedures.  相似文献   
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Abstract:  The question of strengths and weaknesses of national parliaments in EU affairs, one of the most salient in the debate on the democratic legitimacy of the EU, is generally answered by assessing formal parliamentary powers which can influence their governments' EU policy. Such an evaluation, however, is flawed: Formal mandating rights are usually incompatible with the overall logic of parliamentary systems, which explains why most national parliaments make very little use of them. Even more importantly, it unduly reduces parliamentary functions to the legislative or policy-making function. Drawing on agency theory, it will instead be argued that the functions of public deliberation and of holding the government publicly to account are at least as important and therefore need to be included in a redefined concept of parliamentary strength. In particular, the article proposes a distinction between two different elements of accountability—monitoring and political scrutiny—which recognises parliamentary majority and opposition as two distinct agents of the electorate.  相似文献   
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The objective of this study was to develop a two-step strategy for analysis of opiates and cocaine in hair samples involving an immunological screening procedure followed by confirmation of results using gas chromatography-mass spectrometry (GC-MS). A semi-quantitative automated competitive enzyme-linked immunosorbent assay (ELISA) methodology using Oral Fluid Micro-Plate Enzyme Immunoassays (Orasure Technologies, Inc.) was developed and validated. Applicability was proven by analysis of authentic head hair samples from drug users (n=103) and from opiate associated fatalities (n=21). The optimum cutoff values for the ELISA tests were 0.1 ng cocaine-equivalents/mg hair and 0.05 ng morphine-equivalents/mg hair using a 50 mg hair sample. Both ELISA tests had a sensitivity of 100%, the specificity was 66% for cocaine-equivalents and 42% for morphine-equivalents. The intraassay precision was 11% for the cocaine and 3% for the opiates ELISA, while interassay precision was 12% for the cocaine and 4% for the opiates ELISA test. The actual analyte concentrations in the hair samples were determined using GC-MS and were between 0.04 and 5.20 ng/mg for heroin (HER), between 0.04 and 30.01 ng/mg for 6-monoacetylmorphine (MAM), between 0.03 and 11.87 ng/mg for morphine (MOR), between 0.02 and 1.84 ng/mg for codeine (COD), between 0.02 and 2.48 ng/mg for acetylcodeine (AC), between 0.01 and 21.37 ng/mg for cocaine (COC), between 0.03 and 10.51 ng/mg for benzoylecgonine (BE) and between 0.05 and 1.26 ng/mg for cocaethylene (CE). The automated ELISA tests were proven to be valid screening procedures for the detection of cocaine and opiates in hair as confirmed by GC-MS. Screening methods provide rapid and inexpensive automated pre-test procedures to detect drugs in hair or other matrices. For forensic purposes screening therefore represents an ideal complement to routinely applied GC-MS procedures.  相似文献   
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ABSTRACT

How do legislators deal with having preferences that go against those of the principals that they represent in parliament? This article analyzes the debate in the aftermath of the Brexit referendum in the House of Commons to explore the relationship between divergent preferences and legislative speeches. It finds that legislators who defy the will of their country or constituency are rather communicative, and their speeches reveal higher levels of negativity. In contrast, those defying their party refrain from speaking in parliament, but if they speak, they use a significantly less negative language. These findings suggest that legislators behave strategically in deciding whether and how to justify their positions publicly when in conflict with their various principals.  相似文献   
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In 2009 cutoff values of assessment criteria to testify abstinence control in order to estimate driving ability were standardized in Germany. The cutoff values are lower than required in existing guidelines like SAMHSA and there is critical discussion about detection of low concentrations by using immunoassay, especially concerning amphetamines in urine (50 ng/ml). In this study Direct ELISA kits were tested for their applicability to identify the absence of amphetamines, cannabinoids, opiates, cocaine, methadone and benzodiazepines in urine. Results were confirmed by LC/MS or GC/MS analyses. Sensitivity, specificity, predictive values (positive as well as negative) and overall misclassification rates were evaluated by contingency tables and were compared to ROC-analyses. Sensitivity results as well as specificity results were satisfying showing sensitivity values higher than 96% for each analyte. The amphetamine test we used showed sensitivity and specificity of 100% and 88%, respectively, even if amphetamine tests usually react with high cross-reactivity. Our study results include high discrimination at required cutoff values between positives and negatives for each drug group and demonstrate that immunological tests complying with requirements of current decreased urine cutoff values for assessment of driving ability do exist.  相似文献   
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