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21.
It is well established that humans and other animals may treat two perceptually different cues alike, if the cues have been individually paired with a common antecedent or a common consequence. Recently, Molet et al. (Psychon Bull Rev 18:618–623, 2011) reported evidence for a new form of acquired equivalence in human conditional discrimination, namely context-mediated equivalence. In the present research, using a flavor conditioning procedure, we asked whether rats would show similar context-mediated equivalence to demonstrate that this new form of acquired equivalence is a general phenomenon. Rats experienced two flavor cues A and B each presented either in the same context, X, or each in its own distinctive context, X or Y. Subsequently, the rats experienced B with sucrose in a third context, Z, and then the generalization of conditioning to A was assessed. When tested in Context Z, consumption of A was more marked when A and B had both been presented in the same context than when they had been presented in two different contexts. Thus, importantly, in the absence of the training context, cues that shared a common context at different times came to be treated as equivalent. This represents the first evidence of context-mediated equivalence in a nonhuman species.  相似文献   
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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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Social status is associated with the vertical spatial dimension, with people conceptualizing higher social status with higher vertical positions. Two experiments tested whether this association influences relatively real‐world decisions about others by asking participants to act as real estate agents, aiding in the relocation of clients who explicitly or implicitly varied in social status. Across experiments, higher status clients were placed into higher elevation housing options. This influence of social status persisted when strategy‐aware participants were removed from analysis, and was not influenced by individual differences in social dominance or locus of control. Abstract concepts of social status are understood through associations with vertical space, and these mapping of abstract concepts to concrete percepts prove influential in guiding daily decisions.  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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