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851.
由于社会满足不了所有的医疗需求,医疗决策问题变成了确定医疗的限度问题。由于社会对于限度决定很难获得共识,医疗决策要通过公正的程序获得。医疗决策不能由某个人或某个团体或权力机构做出,而应该通过民主协商来做出,否则,人们会质疑医疗决策的合法性。  相似文献   
852.
853.
The Test of Self-Conscious Affect (TOSCA) is a well-established scenario-based questionnaire assessing self-conscious emotions, such as shame and guilt, which have been shown to be differentially associated with a variety of functional, motivational, behavioral and health outcomes. The aim of this study was to evaluate the psychometric properties and internal structure of a Swedish version of TOSCA in a sample of 361 healthy adults. The psychometric properties and internal consistency of the Swedish version were at level with the original US TOSCA version for shame, guilt and detachment. The internal structure of the Swedish version was acceptable for shame, guilt and detachment but contained shortcomings in assessment of externalization.  相似文献   
854.
A hearing loss leads to problems with speech perception; this is exacerbated when competing noise is present. The speech signal is recognized by the cognitive system of the listener; noise and distortion tax the cognitive system when interpreting it. The auditory system must interact with the cognitive system for optimal signal decoding. This article discusses this interaction between the signal and cognitive system based on two models: an auditory model describing signal transmission and degeneration due to a hearing loss and a cognitive model for Ease of Language Understanding. The signal distortion depends on the specifics of the hearing impairment and thus differently distorted signals can affect the cognitive system in different ways. Consequently, the severity of a hearing loss may not only depend on the lesion itself but also on the cognitive recourses required to interpret the signal.  相似文献   
855.
Abstract: The leading accounts of the ethics of proxy decision making implicitly draw on internalist conceptions of the philosophy of mind, or so this essay tries to demonstrate. Using the views of Ronald Dworkin as its jumping-off point, the essay argues that accepting the sort of externalism associated with writers such as Putnam and Burge would alter Dworkin's conclusions concerning how we should respond to the current or precedent decisions of people suffering from dementia. Building on the views of Agnieszka Jawarska, it argues that accepting "active" externalism à la Clark and Chambers would provide currently competent people with new resources for establishing the authority of their present values over inconsistent values they might come to entertain should they become demented.  相似文献   
856.
The paper presents predicate logical extensions of some subintuitionistic logics. Subintuitionistic logics result if conditions of the accessibility relation in Kripke models for intuitionistic logic are dropped. The accessibility relation which interprets implication in models for the propositional base subintuitionistic logic considered here is neither persistent on atoms, nor reflexive, nor transitive. Strongly complete predicate logical extensions are modeled with a second accessibility relation, which is a partial order, for the interpretation of the universal quantifier. Presented by Melvin Fitting  相似文献   
857.
We define a multi-modal version of Computation Tree Logic (ctl) by extending the language with path quantifiers E δ and A δ where δ denotes one of finitely many dimensions, interpreted over Kripke structures with one total relation for each dimension. As expected, the logic is axiomatised by taking a copy of a ctl axiomatisation for each dimension. Completeness is proved by employing the completeness result for ctl to obtain a model along each dimension in turn. We also show that the logic is decidable and that its satisfiability problem is no harder than the corresponding problem for ctl. We then demonstrate how Normative Systems can be conceived as a natural interpretation of such a multi-dimensional ctl logic. Presented by Jacek Malinowski  相似文献   
858.
Successful investors seeking returns, animals foraging for food, and pilots controlling aircraft all must take into account how their current decisions will impact their future standing. One challenge facing decision makers is that options that appear attractive in the short-term may not turn out best in the long run. In this paper, we explore human learning in a dynamic decision making task which places short- and long-term rewards in conflict. Our goal in these studies was to evaluate how people’s mental representation of a task affects their ability to discover an optimal decision strategy. We find that perceptual cues that readily align with the underlying state of the task environment help people overcome the impulsive appeal of short-term rewards. Our experimental manipulations, predictions, and analyses are motivated by current work in reinforcement learning which details how learners value delayed outcomes in sequential tasks and the importance that “state” identification plays in effective learning.  相似文献   
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860.
This experiment examined the relationship between reinforcer magnitude and quantitative measures of performance on progressive‐ratio schedules. Fifteen rats were trained under a progressive‐ratio schedule in seven phases of the experiment in which the volume of a 0.6‐M sucrose solution reinforcer was varied within the range 6–300 μl. Overall response rates in successive ratios conformed to a bitonic equation derived from Killeen's (1994) Mathematical Principles of Reinforcement. The “specific activation” parameter, a, which is presumed to reflect the incentive value of the reinforcer, was a monotonically increasing function of reinforcer volume; the “response time” parameter, δ, which defines the minimum response time, increased as a function of reinforcer volume; the “currency” parameter, b, which is presumed to reflect the coupling of responses to the reinforcer, declined as a function of volume. Running response rate (response rate calculated after exclusion of the postreinforcement pause) decayed monotonically as a function of ratio size; the index of curvature of this function increased as a function of reinforcer volume. Postreinforcement pause increased as a function of ratio size. Estimates of a derived from overall response rates and postreinforcement pauses showed a modest positive correlation across conditions and between animals. Implications of the results for the quantification of reinforcer value and for the use of progressive‐ratio schedules in behavioral neuroscience are discussed.  相似文献   
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