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11.
Escape and avoidance that are disproportional to the danger of the pertinent stimulus are important clinical problems that are often related to inaccurate (catastrophic) expectations. One possible source of such expectations is a prior, underestimated aversive experience. In the present experiment the hypotheses that underestimated pain leads to escape and that it leads to avoidance were tested. In order to control for the effect of the intensity of the pain stimulus, a control group that received 20 pain stimuli of high intensity was formed. Subjects in the experimental condition received 17 pain stimuli of low intensity and 3 of (unexpectedly) high intensity (experimentally induced underprediction). Underprediction of the high intensity stimulus was significantly related to escape, but not to avoidance. The results suggest that the way in which avoidance was operationalized accounts for this. The strong support of the hypothesized relationship between underpredicted pain and escape is an important finding, however.  相似文献   
12.
This case study concerns an 18-year-old bilingual girl who suffered a radiation lesion in the left (dominant) thalamic and temporal region when she was 4 years old. Language and memory assessment revealed deficits in auditory short-term memory, auditory word comprehension, nonword repetition, syntactic processing, word fluency, and confrontation naming tasks. Both languages (English and Dutch) were found to be affected in a similar manner, despite the fact that one language (English) was acquired before and the other (Dutch) after the period of lesion onset. Most of the deficits appear to be related to verbal (short-term) memory dysfunction. Several hypotheses of subcortical involvement in memory processes are discussed with reference to existing theories in this area.  相似文献   
13.
Molecular sequence data, made available in the last 15 years or so, have led to the classification of living cells into three phylogenetic domains: Bacteria, Archaea, and Eucarya. All the organisms that have been tested belonging to either domain were capable of mounting a stress response with essentially the same characteristics, regardless of the stressor. The protagonists in the cell's stress response are the stress genes and their protein products. Some of the latter are molecular chaperones. Under physiological conditions, these chaperones aid other cellular proteins to fold properly and achieve a native -functional- configuration, and to translocate from the place of synthesis to the cell's locale in which they will operate. In a stressed cell, the stress proteins that are chaperones protect other molecules from denaturation and help those partially damaged to regain a functional configuration. Thus, cell death is avoided and recovery is enhanced. The study of stress genes and proteins has progressed considerably in organisms belonging to the domains Bacteria and Eucarya. Less is known about the archaeal stress genes. Here, research with an organism from the Archaea is discussed, focusing on the stress genes of the hsp70 (dnaK) locus. Future perspectives for basic and applied research within the health sciences and biotechnology industries are presented.  相似文献   
14.
W. M. de Muynck 《Synthese》1995,102(2):293-318
The axiomatic approaches of quantum mechanics and relativity theory are compared with approaches in which the theories are thought to describe readings of certain measurement operations. The usual axioms are shown to correspond with classes of ideal measurements. The necessity is discussed of generalizing the formalisms of both quantum mechanics and relativity theory so as to encompass more realistic nonideal measurements. It is argued that this generalization favours an empiricist interpretation of the mathematical formalisms over a realist one.  相似文献   
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16.
Although there are measurable differences in integrative complexity among solutions that individuals generate in dealing with problems, it is uncertain to what extent people comprehend, recognize, and have preferences among different levels of complexity. Integrative complexity is a function of differentiation (the perception of several attributes within, or perspectives about, a topic) and integration (combining the differentiated characteristics in an interactive or synthesizing solution). The current paper reports two experiments dealing with how university students perceive, interpret, and choose among solutions differing in complexity. Experiment 1 showed that subjects accurately rated the complexity of described solutions differing along the continuum, but that their assessment of their own responses differed from the results of expert scoring. Their self-estimated complexity was highly correlated with their preferences, and preferred complexity was reliably higher than either expert- or self-assessed complexity of subject-generated solutions. Subjects were able to hypothesize quite accurately about environmental and endogenous factors likely to affect complexity. Experiment 2 found that in response to problem scenarios, solutions selected as being potentially most effective were consistently more complex than solutions that participants considered themselves most likely to use. The idea of complexity seems to be intuitively recognizable and understandable by untrained subjects: They can and do distinguish among problem solutions (self-generated or presented) that vary on that dimension, and are able to assess accurately the effects of relevant variables. Such subjects also share the bias shown by experts in favour of the superiority of more complex approaches.  相似文献   
17.
In studies related to human movement, linked segment models (LSM's) are often used to quantify forces and torques, generated in body joints. Some LSM's represent only a few body segments. Others, for instance used in studies on the control of whole body movements, include all body segments. As a consequence of the complexity of 3-dimensional (3-D) analyses, most LSM's are restricted to one plane of motion. However, in asymmetric movements this may result in a loss of relevant information. The aim of the current study was to develop and validate a 3-D LSM including all body segments. Braces with markers, attached to all body segments, were used to record the body movements. The validation of the model was accomplished by comparing the measured with the estimated ground reaction force and by comparing the torques at the lumbo-sacral joint that resulted from a bottom-up and a top-down mechanical analysis. For both comparisons, reasonable to good agreement was found. Sources of error that could not be analysed this way, were subjected to an additional sensitivity analysis. It was concluded that the internal validity of the current model is quite satisfactory.  相似文献   
18.
A new computational method to fit the weighted euclidean distance model   总被引:1,自引:0,他引:1  
This paper describes a computational method for weighted euclidean distance scaling which combines aspects of an analytic solution with an approach using loss functions. We justify this new method by giving a simplified treatment of the algebraic properties of a transformed version of the weighted distance model. The new algorithm is much faster than INDSCAL yet less arbitrary than other analytic procedures. The procedure, which we call SUMSCAL (subjectivemetricscaling), gives essentially the same solutions as INDSCAL for two moderate-size data sets tested.Comments by J. Douglas Carroll and J. B. Kruskal have been very helpful in preparing this paper.  相似文献   
19.
We distinguish three different readings of the intuitionistic notions of validity, soundness, and completeness with respect to the quantification occurring in the notion of validity, and we establish certain relations between the different readings. For each of the meta-logical notions considered we suggest that the most natural reading (which is not the same for all cases) is precisely the one which is required by the recent intuitionistic completeness theorems for IPC.This paper was partly written while the first author, H. C. M. de Swart, was a Visiting Fellow at Princeton University for the academic year 1976–1977. This opportunity was given to him by the Niels Stensen Stichting in Amsterdam, the department of philosophy of the Catholic University in Nijmegen and by Princeton University. He is happy to express his appreciation for that opportunity.  相似文献   
20.
Seventy to 80 chronic psychiatric patients are treated in an aftercare clinic with a goal of tertiary preventive care. The major component of the treatment approach is reality-oriented group psychotherapy with an emphasis on interpersonal relationships. Attention to three factors in group psychotherapy with this population of patients has facilitated our work and outcome. These are the concept of the core group, diagnostic heterogeneity, and staff structure.  相似文献   
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