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91.
92.
Two studies tested the impact of an alibi witness’s relationship to a defendant on the perceived credibility of that witness. In the first study, 291 mock jurors estimated the frequency with which individuals would invent alibis, the frequency they themselves would do so, and the frequency of interpersonal contact among individuals of varying relationships. The degree of relationship between an alibi witness and a defendant remained a predictor of witness credibility when contact frequency was controlled. In the second study, 512 mock jurors were randomly assigned to case scenarios. Skepticism toward witnesses who are biologically or affinally related to a defendant was greater than skepticism toward a socially linked witness. Both studies supported predications from kinship theory and reciprocal altruism.  相似文献   
93.
In post-mortem work, blood is a potential source of external contamination of hair. The present study was carried out to investigate the amount of drug absorbed into hair which has been contaminated with blood containing either cocaine or BE. Solutions were prepared containing 0.05, 0.1, 0.2, 0.5 and 3.0 μg/mL of either cocaine or BE in human blood. Samples of approximately 3.2 g of drug-free hair were contaminated by soaking in the blood solutions for 5 min. They were then removed and left at room temperature. Approximately 0.5 g of hair was collected from each of the blood soaked hair samples at 6 h, 1, 2, 4 and 7 days after contamination. As each hair sample was collected it was shampoo-washed to prevent further drug absorption. Hair samples were analysed in triplicate using a fully validated method described previously. EME and cocaethylene were also measured in order to find out if cocaine or BE was breaking down to these compounds. Both cocaine and BE were absorbed into hair in significant concentrations when the concentration in the blood was 0.5 μg/mL or greater; cocaine was more readily absorbed than BE. Cocaine broke down to EME (<LOQ) at 0.5 μg/mL and to EME (>LOQ) and BE (<LOQ) at 3.0 μg/mL. When the blood concentration of cocaine was 0.5 μg/mL or less, there was no evidence of it breaking down to form BE. From the samples soaked in blood containing BE, there was no evidence of the BE breaking down. The absorption of drug into hair did not increase as the contamination period increased from 6 h to 7 days.  相似文献   
94.
95.
Abstract. The purpose of this paper is to estimate popularity functions for the Portuguese Prime Minister, Government, Parliament and President using the ordinary least squares (OLS) and seemingly unrelated regressions (SUR) methods. The results indicate that: (1) popularity polls for the Prime Minister and Government are better explained by economic conditions than are similar polls for the Parliament and President; (2) unemployment is a significant variable determining popularity while inflation is not; (3) honeymoon effects are significant; (4) popularity deteriorates over consecutive terms.  相似文献   
96.
97.
1,4-Dihydropyridines calcium channel antagonists (1,4-DHP CCAs) are photolabile and the products of their photodecomposition have no pharmaceutical activity. In our previous work we have presented a screening procedure for eleven 1,4-DHPs in plasma by LC-MS-MS using multiple reaction motoring. The laboratory process includes preparation and storage of stock solutions, plasma storage, solid-phase extraction, reconstitution of extracts and storage time in an autosampler for LC-MS-MS analysis. Prior to validation of the analytical procedure, we have tested the stability of these compounds by exposure to light. Methanolic solutions have been exposed to laboratory and UV light and the stability of the compounds in plasma was tested by exposure of spiked plasma samples to laboratory light at room temperature. Stability during freeze-thaw cycles and stability during 2 month storage at -20 degrees C have been tested as well. Products of photodecomposition have been identified after forced degradation and the degree of degradation has been quantified using LC-UV-DAD and LC-MS-MS, respectively. A 96% degradation after only 2h has been observed when solutions of nifedipine or nisoldipine were exposed to laboratory light in clear glass vials. In plasma samples degradation was 25% in only 2h for both compounds. The main degradation product was produced by oxidation of the dihydropyridinic ring resulting in the pyridine analogue that has been described as the first metabolite in the metabolic pathway. Only minor degradation was found for the other tested compounds after 2h light exposure in methanolic solutions. Furthermore, lercanidipine and nicardipine were also degradated by esterhydrolysis. Several additional minor degradation products were found for the other tested 1,4-DHPs, however, some of them could not be identified. Preconditions for storage and handling of plasma samples prior to and during analysis for 1,4-DHP CCAs are suggested in order to avoid photodecomposition of the analytes.  相似文献   
98.
The Brazilian polymer industry (plastics, rubbers, fibers, adhesives, paints, and varnishes) is the fastest growing segment of the Petrochemical Chain. Since the polymer industry is characterized as science based, the capacity to create technology is vital for its long-range survival in the market. This paper analyzes how Brazilian polymer firms maintain their technological competitiveness, explains the main modes of technology transfer, and evaluates the degree of technological dependence of this industry. The methodology consisted of a database built with data from the Brazilian Patent Office. To confirm the findings, interviews were conducted with staff members from seven Brazilian polymer firms. The data base analysis and the interviews reveal that, in spite of the fact that Research and Development (R&D) and technological innovation have a fundamental role in their competitiveness, the firms are technologically dependent upon foreign suppliers.  相似文献   
99.
A fundamental dilemma which troubles advocates of interinstitutional partnerships in regional development pertains to the extent to which partnerships enhance the effectiveness of governance processes and outcomes. This dilemma is particularly relevant in contexts that lack strong cohesive regional development alliances, such as the Portuguese case. This article aims to shed light on the debate regarding the role of partnerships in regional development, drawing on a unique collaborative interinstitutional partnership. It explores the responses to complexity across the different stakeholders, as well as its effects at the formulation and implementation stages of the strategic plans devised to apply for EU funding. Findings suggest that interinstitutional partnerships induce significantly different allocative choices at the agenda-setting. However, the established partnership was unable to cope with the several obstacles that emerged during the implementation, suggesting several vulnerabilities of partnerships, which are explored. Findings suggest the need to reinforce governance mechanisms during the implementation stage.  相似文献   
100.
In this study, we applied an evolutionary perspective to analyze the relationship between aggressiveness, academic performance, and sociality in a population of 528 adolescents of both sexes. In men, we expect physical aggression (PA) and sociality to be negative predictors of academic performance. However, in women, PA would be a negative predictor of academic performance, and sociality a positive one. Our results report a negative association between academic performance and PA in both sexes. As we expected, social effect derived from the use of PA seems to be different for each sex, where men could display a rebellious attitude to increase chances of finding a mate. In contrast, results for women are not conclusive, because no relationship between academic performance and any aggressive mechanism, were predicted by sociality. We conclude that an evolutionary framework, which includes sex-specific hypotheses, is appropriate to obtain a holistic perspective of this phenomenon.  相似文献   
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