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871.
Medicalization has been a process articulated primarily by social scientists, historians, and cultural critics. Comparatively little is written about the role of bioethics in appraising medicalization as a social process. The authors consider what medicalization means, its definition, functions, and criteria for assessment. A series of brief case sketches illustrate how bioethics can contribute to the analysis and public policy discussion of medicalization.  相似文献   
872.
To examine the extent of automaticity of emotional face processing in high versus low trait anxious participants, event-related potentials (ERPs) were recorded to emotional (fearful, happy) and neutral faces under varying task demands (low load, high load). Results showed that perceptual encoding of emotional faces, as reflected in P1 and early posterior negativity components, was unaffected by the availability of processing resources. In contrast, the postperceptual registration and storage of emotion-related information, as reflected in the late positive potential component at frontal locations, was influenced by the availability of processing resources, and this effect was further modulated by level of trait anxiety. Specifically, frontal ERP augmentations to emotional faces were eliminated in the more demanding task for low trait anxious participants, whereas ERP enhancements to emotional faces were unaffected by task load in high trait anxious participants. This result suggests greater automaticity in processing affective information in high trait anxious participants.  相似文献   
873.
Dopamine plays a critical role in regulating neural activity in prefrontal cortex (PFC) and modulates cognition via a hypothesized inverse U function. We investigated PFC function in children with chromosome 22q11.2 deletion syndrome (22q11.2DS) in which one copy of catechol-O-methyltransferase (COMT) is deleted, thereby shifting them toward the lower end of dopamine turnover on the nonlinear function. A common polymorphism with valine to methionine substitution alters COMT activity that results in higher enzyme activity in the valine variant. Twenty-seven children with 22q11.2DS between 7 and 14 years old, and 21 age-matched typically developing children, performed a modified version of the Attention Network Test. Children with a single valine allele showed a reduction in response times when trials with incongruent flankers were repeated, whereas those who were hemizygous for the methionine allele did not show the same context-based response facilitation. Our results support that a single gene, COMT, could modulate PFC-dependent cognition.  相似文献   
874.
When experiencing aggression from group members, chimpanzees commonly produce screams. These agonistic screams are graded signals and vary acoustically as a function of the severity of aggression the caller is facing. We conducted a series of field playback experiments with a community of wild chimpanzees in the Budongo Forest, Uganda, to determine whether individuals could meaningfully distinguish between screams given in different agonistic contexts. We compared six subjects’ responses to screams given in response to severe and mild aggression. Subjects consistently discriminated between the two scream types. To address the possibility that the response differences were driven directly by the screams’ peripheral acoustic features, rather than any attached social meaning, we also tested the subjects’ responses to tantrum screams. These screams are given by individuals that experienced social frustration, but no physical threat, yet acoustically they are very similar to screams of victims of severe aggression. We found chimpanzees looked longer at severe victim screams than either mild victim screams or tantrum screams. Our results indicate that chimpanzees attend to the informational content of screams and are able to distinguish between different scream variants, which form part of a graded continuum.  相似文献   
875.
This study reports an experiment that compared the hazard perception abilities of experienced and novice motorcycle riders using an interactive, closed-loop, simulator. Participants (n = 49) were categorized into four groups: experienced motorcycle riders with full driver licence, inexperienced motorcycle riders with full driver licence, novice motorcycle riders with full driver licence, and novice motorcycle riders with probationary driver licence. The participants were tested on three scenarios, each consisting of eight hazardous events. They were instructed to ride normally, but to respond appropriately to avoid the hazards. Under certain conditions in the simulator, we found that experienced riders (relative to inexperienced or novice riders) crashed less often, received better performance evaluations, and approached hazards at more appropriate speeds. Interestingly, we also found that some novice riders were overconfident in their riding ability. We discuss how this overconfidence might be related to hazard perception.  相似文献   
876.
877.
Focus particles such as only and even indicate that the focused element(s) in a sentence should be contrasted with a set of contextually defined alternatives. Only indicates that properties assigned to the focus set are not shared by elements of the alternative set, whereas even indicates that the focus and alternative sets share the properties mentioned in the sentence. Even has the additional function of marking the focused element as being low on a scale of alternatives ranked in terms of likelihood, thereby signaling that what is being described is somewhat surprising. Using eyetracking, we demonstrate that contrast information associated with only and even is rapidly processed online, with effects for even being delayed, as compared with only (Experiment 1). This difference in time course was not driven by the underlying semantics of the sentence without the focus particle (Experiment 2) but was probably due to even’s more complex semantic function.  相似文献   
878.
We defend Joseph Melia's thesis that the role of mathematics in scientific theory is to 'index' quantities, and that even if mathematics is indispensable to scientific explanations of concrete phenomena, it does not explain any of those phenomena. This thesis is defended against objections by Mark Colyvan and Alan Baker.  相似文献   
879.
The Scharff technique aims to elicit information by affecting the source's perception of the interviewer's existing knowledge. Although the technique has been found to be effective for gathering new information, countermeasures to the technique have not been examined. In a 2 × 2 between‐subjects experiment, we informed half of the 120 sources about the counter‐interrogation strategy of carefully considering the interviewer's prior knowledge and the tactic of providing information perceived as already known to the interviewer. After this, sources were interviewed with the Scharff technique or the Direct approach, widely used in human intelligence‐gathering situations and consisting of open‐ended and direct questions. We found that “informed sources” did not succeed in revealing information already known to the interviewer, where informed sources and uninformed sources revealed known information to a similar degree (1.62 pieces vs. 1.65 pieces). Sources interviewed with the Direct approach (vs. Scharff technique) revealed a larger amount of information previously known to the interviewer (2.18 pieces vs. 1.08 pieces). When interviewed with the Scharff technique, sources informed about the counter‐interrogation strategy attempted to adopt more counter‐interrogation strategies. The present study replicates earlier research on the Scharff technique as a technique effective in affecting the source's perception of the interviewer's prior knowledge. The results of the current study indicate that both the Scharff technique and the Direct approach might be similarly robust against counter‐interrogation strategies, in terms of gathering new information. Future studies should focus on implementing more comprehensive training in counter‐interrogation strategies for the sources.  相似文献   
880.
The Processes of Scientific Discovery: The Strategy of Experimentation   总被引:1,自引:0,他引:1  
Hans Krebs' discovery, in 1932, of the urea cycle was a major event in biochemistry. This article describes a program, KEKADA, which models the heuristics Hans Krebs used in this discovery. KEKADA reacts to surprises, formulates explanations, and carries out experiments in the same manner as the evidence in the form of laboratory notebooks and interviews indicates Hans Krebs did. Furthermore, we answer a number of questions about the nature of the heuristics used by Krebs, in particular: How domain-specific are the heuristics? To what extent are they idiosyncratic to Krebs? To what extent do they represent general strategies of problem-solving search? The relative generality of KEKADA allows us to view the control structure of KEKADA and its domain-independent heuristics as a model of scientific experimentation that should apply over a broad domain.  相似文献   
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