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21.
The failure of sewage treatment plants to remove pharmaceuticals such as fluoxetine from waste water has become a concern given that these products are being detected in the surface waters of many countries of the world. The effects of fluoxetine in sub-lethal doses on the neural systems and behaviors of aquatic life are worthy of investigation. This study investigated the effects of sub-lethal amounts fluoxetine dissolved in water on the aggressive and locomotor behaviors of 44 male Betta splendens. Fish treated with 705 microg/l of fluoxetine and 350 microg/l of fluoxetine generally demonstrated significant decreases in locomotion and number of aggressive attacks compared to 0 microg/l of fluoxetine (controls) on Days 11 and 19 of drug exposure and persisted for at least 13 days after removal of fluoxetine. Consistent with decreases in the number of aggressive attacks, there was a significant increase in aggression-response time to a perceived intruder for treated males on Days 11 and 19 and persisted for 6 days following removal of fluoxetine. However, the differences in aggressive and locomotor behaviors seen in the fluoxetine-treated groups were indistinguishable from controls three weeks following drug removal.  相似文献   
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Holly Andersen 《Synthese》2012,189(3):415-432
How regular do mechanisms need to be, in order to count as mechanisms? This paper addresses two arguments for dropping the requirement of regularity from the definition of a mechanism, one motivated by examples from the sciences and the other motivated by metaphysical considerations regarding causation. I defend a broadened regularity requirement on mechanisms that takes the form of a taxonomy of kinds of regularity that mechanisms may exhibit. This taxonomy allows precise explication of the degree and location of regular operation within a mechanism, and highlights the role that various kinds of regularity play in scientific explanation. I defend this regularity requirement in terms of regularity??s role in individuating mechanisms against a background of other causal processes, and by prioritizing mechanisms?? ability to serve as a model of scientific explanation, rather than as a metaphysical account of causation. It is because mechanisms are regular, in the expanded sense described here, that they are capable of supporting the kinds of generalizations that figure prominently in scientific explanations.  相似文献   
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This paper explores a distinction between two types of response-dependence (RD) account (shallow vs. deep). This distinction is inherent in much of the existing literature, however it is neither widely nor well understood, and has never been drawn explicitly. The distinction is often taken to be a metaphysical, or ‘realism-relevant’ one—i.e. deep RD accounts entail qualified realism (or perhaps anti-realism), while shallow RD accounts are metaphysically neutral. I argue that the distinction is not reliably realism-relevant. I formulate a weaker version of the distinction that may help prevent some common and understandable confusion about RD biconditionals and their relationship to realism. The weaker distinction rests on the different roles assigned to RD biconditionals by the two types of account.  相似文献   
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The purpose of the present study was to investigate the relationship between brand names and consumers' perceived risk. Hypotheses dealt with whether the presence of a product's brand name affects consumers' perceived risk towards shopping online; whether the familiarity with a brand name influences consumers' perceived risk; and whether online shoppers and non‐shoppers perceive risk towards shopping online differently. Results indicate that the presence or absence of a product's brand name affects online shoppers' perceived risk, but in the opposite direction to that expected. There was no significant difference between online shoppers' perceived risk vis‐à‐vis brand familiarity; however, online shoppers possessed lower perceived risk than non‐shoppers. Implications and limitations are discussed and recommendations for future research are provided. Copyright © 2004 Henry Stewart Publications Ltd.  相似文献   
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Duchenne/Becker muscular dystrophy (DBMD) and spinal muscular atrophy (SMA) are rare neuromuscular disorders that present challenges to therapeutic and clinical trial decision making. We developed an interactive, evidence-based online tool designed to encourage thoughtful deliberation of the pros and cons of trial participation and to inform meaningful discussions with healthcare providers. Prior research demonstrates the importance of tool availability at the time each family is considering trial participation, which may be prior to the informed consent process. The tool is intended to be easily modified to other pediatric disease communities. Tool development was informed by prior qualitative research, literature reviews, and stakeholder input. Specific items were derived based on an online exploratory questionnaire of parents whose children participated in a trial for DBMD or SMA to understand motivations for participation. Parent participants in the exploratory survey reported strong impact of altruistic and individual benefit motivations and placed much greater emphasis on anticipated trial benefits than on harms when making participation decisions. We used this data to develop the evidence-based deliberation tool using a community-engaged approach. We initially targeted the tool for DBMD while using SMA survey data to evaluate ease of transition to that population. We conducted two iterative sets of activities to inform development and refinement of the tool: (1) community engagement of key stakeholders and (2) user experience testing. These activities suggest that the tool may increase deliberation and the weighing of benefits and harms. Ongoing evaluation will determine the acceptability and efficacy of this online intervention.  相似文献   
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An environmental scan (ES) is an efficient mixed-methods approach to collect and interpret relevant data for strategic planning and project design. To date, the ES has not been used nor evaluated in the clinical cancer genetics setting. We created and implemented an ES to inform the design of a quality improvement (QI) project to increase the rates of adherence to national guidelines for cancer genetic counseling and genetic testing at three unique oncology care settings (OCS). The ES collected qualitative and quantitative data from reviews of internal processes, past QI efforts, the literature, and each OCS. The ES used a data collection form and semi-structured interviews to aid in data collection. The ES was completed within 6 months, and sufficient data were captured to identify opportunities and threats to the QI project’s success, as well as potential barriers to, and facilitators of guideline-based cancer genetics services at each OCS. Previously unreported barriers were identified, including inefficient genetic counseling appointment scheduling processes and the inability to track referrals, genetics appointments, and genetic test results within electronic medical record systems. The ES was a valuable process for QI project planning at three OCS and may be used to evaluate genetics services in other settings.  相似文献   
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Emotion regulation may influence psychological responses to exercise. We examined whether the emotion regulation strategies, cognitive reappraisal and distraction, influenced psychological state and prefrontal cortex oxygenation during endurance exercise. Twenty-four endurance runners ran for 90 min at 75–85% maximum heart rate in three separate sessions with no instruction or with instructions to use cognitive reappraisal or distraction. Participants rated their emotional arousal, emotional valence, and perceived exertion before, every 30 min during, and after exercise. Functional near-infrared spectroscopy quantified changes in prefrontal cortex oxygenation. Participants felt lower emotional arousal and physical exertion when instructed to utilize cognitive reappraisal than when given no emotion regulation instruction. Such responses to distraction did not differ from the other conditions. Emotion regulation strategies did not influence emotional valence or prefrontal cortex oxygenation. Participants’ analytical interpretation of the cognitive reappraisal instruction could contribute to small effect sizes and limited effects. Further research should determine contexts under which emotion regulation strategies most benefit endurance exercise experience.  相似文献   
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