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141.
Impedance cardiography has been used increasingly to measure human physiological responses to emotional and mentally engaging stimuli. The validity of large-scale ensemble averaging of ambulatory impedance cardiograms was evaluated for preejection period (PEP), interbeat interval, and dZ/dt(min) amplitude. We tested whether the average of “classical” 60-sec ensemble averages across periods with fixed activity, posture, physical load, social situation, and location could be accurately estimated from a single large-scale ensemble average spanning these entire periods. Impedance and electrocardiograms were recorded for about 24-h from 21 subjects. Recordings were scored by seven raters, using both methods for each subject. Good agreement (average intraclass correlation coefficient was .91) between both ensemble averaging methods was found for all three cardiac function measures. The results indicate that for unambiguous ambulatory impedance cardiograms, large-scale ensemble averaging is valid, which makes measuring prolonged changes in cardiac sympathetic activity by measuring ambulatory PEP feasible even in large epidemiological samples.  相似文献   
142.
The aim of this work was to examine how the presence of inapplicable items might change the factor structure of the 1984 Ways of Coping Questionnaire by Lazarus and Folkman. The Spanish version of the Ways of Coping Questionnaire was administered to 156 subjects with university degrees. The 95 women and 61 men whose ages were from 18 and 45 years (M = 27.8, SD = 12.1) were of middle socioeconomic status. All were residents of Buenos Aires. To study whether relevant items modify the factor structure of the Ways of Coping Questionnaire, two factor analyses were carried out, one with items rated as not relevant (Item Mean) and the other with the same items rated as not chosen. In both factor analyses, principal axes method and oblimin rotation were performed, and five factors were considered. Congruence indexes were performed. Analysis showed that not choosing an item because it does not coincide with one's behavior or ideas is not the same as not selecting that item because it does not apply to the current threatening situation. Lack of discrimination between situations when analyzing data leads to a distorted interpretation of the way in which the subject actually behaves or copes with the situation.  相似文献   
143.
The long-term effect of transplanting embryonic frontal cortex into a unilateral frontal cortex lesion has been studied in adult rats. Before surgery, activity in an open field, muscular strength of both forelimbs, and performance in a paw-reaching-for-food task were scored in 26 rats. In 21 animals a unilateral cortex lesion was then made in the forelimb motor area of the hemisphere contralateral to the preferred paw in the paw-reaching-for-food task, while the other 5 animals were sham-operated. On retesting, the lesion animals changed the preferred paw. A solid homotopic transplant of embryonic tissue (embryonic day 17) was then placed in the lesion cavity in 11 of the lesion rats. Three months later neither lesion alone nor lesion plus transplantation affected open field behavior and muscular strength, but the lesion permanently affected performance in the paw-reaching-for-food task, as shown by a change of preferred paw and a functional deficit in the paw contralateral to the lesion. Transplantation ameliorated the deficits caused by the lesion, but this was only evident when animals were forced to reach with the paw contralateral to the lesion plus transplant. The behavioral results were independent of the size of the lesion and graft. Connections between graft and host tissue were studied by means of the fluorescent tracer 1,1'-dioctadecyl-3,3,3'3'-tetramethylindocarbocyanine perchlorate (DiI). A dense array of labeled fibers was found in the host cortex adjacent to the transplant. The results suggest that functional recovery depends on grafting but is only evident when the animal is obliged to use the affected limb.  相似文献   
144.
This article reports on the development and teaching of compulsory courses on ethics and engineering at Delft University of Technology (DUT). Attention is paid to the teaching goals, the educational setup and methods, the contents of the courses, involvement of staff from engineering schools, experiences to date, and challenges for the future. The choices made with respect to the development and teaching of the courses are placed within the European and Dutch context and are compared and contrasted with the American situation and experiences. Previous versions of this article were presented at the meeting of the SEFI Working Group on Engineering Ethics in Rzeszow, Poland, April 29–May 1, 1999 and at the SEFI Annual Conference in Zurich, Switzerland, September 1–3, 1999.  相似文献   
145.
In this editorial contribution, two issues relevant to the question, what should be at the top of the research agenda for ethics and technology, are identified and discussed. Firstly: can, and do, engineers make a difference to the degree to which technology leads to morally desirable outcomes? What role does professional autonomy play here, and what are its limits? And secondly, what should be the scope of engineers' responsibility; that is to say, on which issues are they, as engineers, morally obliged to reflect? The research agendas proposed by the authors contributing to this special section, implicitly, give different answers to these questions. We suggest that an explicit discussion of these issues would greatly help in constructing a common research agenda.  相似文献   
146.
Despite the major advances in the development of treatments for bulimia nervosa, drop-outs and a lack of engagement in treatment, continue to be problems. Recent studies suggest that the transtheoretical model of change may be applicable to bulimia nervosa. The aim of this study was to examine the roles of readiness to change and therapeutic alliance in determining engagement and outcome in the first phase of treatment. One hundred and twenty five consecutive female patients meeting DSM-IV criteria for bulimia nervosa took part in a randomised controlled treatment trial. The first phase of the sequential treatment compared four sessions of either cognitive behavioural therapy (CBT) or motivational enhancement therapy (MET) in engaging patients in treatment and reducing symptoms. Patients in the action stage showed greater improvement in symptoms of binge eating than did patients in the contemplation stage. Higher pretreatment scores on action were also related to the development of a better therapeutic alliance (as perceived by patients) after four weeks. However, pretreatment stage of change did not predict who dropped out of treatment. There were no differences between MET and CBT in terms of reducing bulimic symptoms or in terms of developing a therapeutic alliance or increasing readiness to change. The results suggest that the transtheoretical model of change may have some validity in the treatment of bulimia nervosa although current measures of readiness to change may require modification. Overall, readiness to change is more strongly related to improvement and the development of a therapeutic alliance than the specific type of treatment.  相似文献   
147.
Both cross-sectional and longitudinal studies in the United States have shown consistent changes between college age and middle adulthood. There appear to be declines in 3 of the 5 major factors of personality--Neuroticism, Extraversion, and Openness--and increases in Agreeableness and Conscientiousness. To examine cross-cultural generalizability of these findings, translations of the Revised NEO Personality Inventory were administered to samples in Germany, Italy, Portugal, Croatia, and South Korea (N = 7,363). Similar patterns of age differences were seen in each country, for both men and women. Common trends were also seen for the more specific traits that define the major factors. Because these nations differ substantially in culture and recent history, results suggest the hypothesis that these are universal maturational changes in adult personality.  相似文献   
148.
Further evidence for feature correlations in semantic memory.   总被引:4,自引:0,他引:4  
The role of feature correlations in semantic memory is a central issue in conceptual representation. In two versions of the feature verification task, participants were faster to verify that a feature (< is juicy >) is part of a concept (grapefruit) if it is strongly rather than weakly intercorrelated with the other features of that concept. Contrasting interactions between feature correlations and SOA were found when the concept versus the feature was presented first. An attractor network model of word meaning that naturally learns and uses feature correlations predicted those interactions. This research provides further evidence that semantic memory includes implicitly learned statistical knowledge of feature relationships, in contrast to theories such as spreading activation networks, in which feature correlations play no role.  相似文献   
149.
The ESPbase provides a tool for storing symbols and icons along with information about their characteristics. Information about a wide range of symbol characteristics is included on the database to facilitate the selection of symbol sets for research and design. The database includes information about the graphical characteristics and functions of symbols. It also includes ratings of symbol concreteness, complexity, familiarity, and meaningfulness. Symbols and icons can be accessed on the basis of each of these characteristics or any combination of characteristics. This makes it easier to select symbols on the basis of usability and design requirements. It also means that symbols can be easily selected for research while controlling their characteristics on a number of dimensions.  相似文献   
150.
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