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181.
Cortisol can be used to indicate stress level as well as to monitor certain disease states. Although cortisol can be sampled from blood and urine, saliva sampling has decided advantages. Unfortunately, whole saliva contains a number of substances that can metabolize or bind with cortisol, potentially confounding analysis and quantitation. We introduce a semipermeable pouch that accumulates a contaminant-free salivary ultrafiltrate, thereby overcoming a number of the problems encountered with whole saliva. In three studies, we demonstrate accuracy and utility of the device for cortisol determination: (1) in an artificial medium, 60%–77% of the cortisol was recovered in the ultrafiltrate; (2) in vivo, ultrafiltrate cortisol correlated highly with whole-saliva cortisol collected under ideal conditions; and (3) ultrafiltrate cortisol evinced positive relationships with depression and cigarette use, consistent with studies in the literature. We conclude that this device and saliva-filtering technologies in general are useful in applications requiring quantitation of cortisol.  相似文献   
182.
A technique is described for rapidly collecting responses in auditory-localization experiments. Subjects indicate the perceived direction of the sound by pointing at a 20-cm-diam spherical model. In Experiment 1, the subjects judged the direction of a broadband signal, which could originate from any of 239 directions ranging through 360° of azimuth and between ?45° and +90° of elevation. Using this technique, the subjects responded 2–8 times more rapidly than previous subjects who used either a verbal-reporting technique or a head-pointing technique. Localization judgments were as accurate as they had been with verbal reports, but were not as accurate as judgments collected using the head-pointing technique. In Experiment 2, the signal was turned off and the experimenter read the spherical coordinates of the signal location to the subjects. The subjects pointed to these coordinates more accurately than they had judged the direction of the sounds in Experiment 1, suggesting that the response technique had not been the limiting factor in that experiment. Circumstances relevant to the choice of response techniques for auditory-localization experiments are discussed.  相似文献   
183.
The inhibition of return of visual attention based on stimulus color was examined in three experiments. In the first experiment, a discrete trial paradigm showed that subjects were slower to detect a color patch if the color matched that of a patch presented earlier in the same location. Experiment 2 showed that the inhibition only occurs if a neutral, nontarget distractor color is presented between presentation of the initial color cue and the subsequent target patch—explaining the previous failures to detect the phenomenon. Experiment 3 extended the results to a different combination of colors. Taken together, the results have important implications for the processing of stimulus attributes such as spatial location and color, and for the conditions necessary for producing inhibition of return.  相似文献   
184.
This study examined the mediating role of anxiety in the self-reports of somatic complaints in 96 depressed adolescent inpatients. Sixty-four subjects with major depressive episodes and comorbid anxiety disorders (MDE-A) determined from the Diagnostic Interview for Children and Adolescents-Revised (DICA-R) reported significantly more somatic complaints than 32 adolescents having major depressive episodes without comorbid anxiety (MDE). An analysis of covariance demonstrated that, with anxiety symptoms controlled, MDE and MDE-A groups did not differ significantly in somatic complaints. A hierarchical multiple-regression analysis revealed that, with demographic and anxiety symptoms controlled, depressive symptoms did not contribute to the explanation or prediction of somatic complaints. The results suggest that anxious, but not depressive symptoms, are independently associated with somatic complaints. The results are discussed in light of new affective models of psychopathology.  相似文献   
185.
Individual differences in selection of intensity of angry interactions and physiological and self-reported responses to interadult anger were examined in preschoolers (N=34). Children watched two videotaped angry interactions between adults, while their heart rates and skin conductance responses and levels were monitored; then they were interviewed. Before the second argument, children were given the perceived choice of watching an intense or mild angry exchange. Individual differences in responding to the angry interactions were found. Both (a) children with relatively higher externalizing behavior problems and (b) boys who chose to watch intense anger had lower tonic heart rates; 80% of boys with externalizing problems chose to watch intense anger. Further, children who chose to watch intense anger (a) exhibited lower declines in heart rates upon the presentation of the argument, (b) perceived the actors as more angry, and (c) reported lower amounts of distress during the argument than those who chose mild anger.  相似文献   
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187.
Indirect modes of aggression among women of Buenos Aires,Argentina   总被引:1,自引:0,他引:1  
This study utilizes the construct indirect aggression to investigate aggressive behavior among middle class Argentine women and men by administering an attitude and self-report survey to 95 inhabitants of Buenos Aires and by analyzing ethnographic interviews and observations conducted over a nine month period in 1992. An examination of sex roles in Argentina, including machismo and marianismo, provide a cultural context for interpreting aggression. Factor analyses revealed the presence of indirect aggression (e.g., social manipulation, gossip, exclusion) in addition to verbal and physical aggression. Survey and ethnographic findings converge in suggesting that women employ more indirect aggression than men, while men utilize more physical aggression. While competition and aggression are salient elements of social life for both sexes, women and men tend to favor different approaches. The findings are compared with the literature on female aggression from other cultural settings. We conclude that cultural and evolutionary perspectives elucidate aspects of female aggression.We would like to thank the Ford Foundation for providing the financial support to make this research possible. We would also like to thank Patricia de Gyldenfeldt and Debbie Bandura for their endless contributions with translations, ideas, and help in general. Finally, we would like to thank Eckerd College, la Universidad del Salvador, and Michael Hobson for their base of support, all those in Argentina, especially Agueda, Andrea, Carmen, Cecilia, Claudio, Daniela, Heidi, Ingrid, Javier, Julio, María, Mariela, Roberto, and Victor, who offered their enthusiastic assistance and ideas, and Victoria Burbank, Ayala Gabriel, and the anonymous reviewer for their helpful suggestions.  相似文献   
188.
189.
Pigeons were trained on two independent matching-to-duration-samples tasks; one involved 2- and 10-s durations and color choice stimuli, and the other involved 4.5- and 22.5-s durations and line choice stimuli. Accuracy was above chance on mixed-choice probes in which either of the short-duration samples was followed by the two short-associated stimuli. Following explicit training on mixed-choice trials involving choice between the two short- and the two long-associated stimuli, a choose-short effect was demonstrated with both sets of duration samples. These findings are inconsistent with the possibility that the choose-short effect reflects processes of asymmetrical-sample coding and default responding.  相似文献   
190.
Douglas N. Walton 《Synthese》1994,100(1):95-131
The aim of this paper is to make it clear how and why begging the question should be seen as a pragmatic fallacy which can only be properly evaluated in a context of dialogue. Included in the paper is a review of the contemporary literature on begging the question that shows the gradual emergence over the past twenty years or so of the dialectical conception of this fallacy. A second aim of the paper is to investigate a number of general problems raised by the pragmatic framework.The work in this paper was supported by a Fellowship from the Netherlands Institute for Advanced Study in the Humanities and Social Sciences (NIAS) and a Research Grant from the Social Sciences and Humanities Research Council of Canada. Thanks are due to Erik Krabbe for discussions, and to the members of the NIAS Research Group on Fallacies as Violations of Rules of Argumentative Discourse: Frans van Eemeren, Rob Grootendorst, Sally Jackson, Scott Jacobs, Agnes Haft van Rees, Agnes Verbiest, Charles Willard, and John Woods.  相似文献   
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