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791.
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   
792.
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   
793.
When children aged from 1;6 to 3;6 made errors in relation to targeted morphemes within grammatically obligatory contexts, a prompt of “Pardon?” was given. Morpheme repair rates increased with linguistic proficiency, and with target morpheme mastery. The selective use of prompted repairs appears to be a useful technique for assessing rudimentary abilities to monitor grammatical form within very young children.  相似文献   
794.
As the AIDS epidemic continues unabated, there is growing clinical evidence that the catastrophic nature of this disease is creating a second category of trauma casualties. They are the health care practitioners who witness the narratives of those who are living with and dying from AIDS. This article examines how multiple AIDS-related deaths of group members exert a traumatizing effect on group therapists, creating vicarious traumatization. Vignettes are presented that illustrate reactions associated with traumatic stress, including death images, survivors' guilt, psychic numbing, suspicion of counterfeit nurturance, and struggle for meaning. Possible therapeutic interventions for group therapists coping with multiple deaths are also explored.The author wishes to acknowledge the endeavors of the volunteer group therapists and the Clinical Group Services staff of the Gay Men's Health Crisis of New York City, who provide group therapy to over 900 clients a week. This article is written in admiration of their extraordinary effort and dedication.  相似文献   
795.
796.
Roy A. Rappaport 《Zygon》1994,29(3):331-349
Abstract. Issue is taken with Dawkins and Krebs's (1978) conception of communication as being by nature manipulative and with Cronk's proposals concerning the evolution of morality, both of which are grounded in evolutionary biology. An alternative view, which recognizes that which humanity has in common with other species but which emphasizes humanity's distinctiveness, is offered to account for religion and morality.  相似文献   
797.
Subjects produced speeded and unspeeded hand movements to a target location after either saccadic or pursuit eye movements to the target. Hand movements began either aligned with the initial position of gaze or from some other location. Subjects generally underestimated the extent of the pursuit eye movements relative to estimates made after saccades. With speeded hand movements, however, the underestimation was reduced considerably if the hand movements began aligned with a location other than the initial position of gaze. The results reveal details of the mechanisms underlying eye-hand coordination and show that important differences exist in the information used for localization for slow and rapid limb movements.  相似文献   
798.
Male Siamese fighting fish, Betta splendens, swam through a ring in an aquarium, breaking a photocell beam and initiating an unsignaled, resetting delay interval. Following delays of 0 s, 10 s, or 25 s, a 15-s mirror presentation released an aggressive display by the fish. Swimming through the ring increased in the absence of either a period of acclimatization to the reinforcer (analogous to magazine training when appetitive reinforcers are used) or explicit training of the response by the experimenters. Response rates were a decreasing function of delay duration. Other fish exposed to a schedule of response-independent mirror presentations failed to acquire and maintain the response. The results demonstrate the robustness and generality of the phenomenon of response acquisition with delayed reinforcement. They further qualify earlier observations about behavioral mechanisms involved in the phenomenon.  相似文献   
799.
Three rats, lever pressing for food delivered on a fixed-interval 128-s schedule, were presented with a 16-s opportunity to drink from a retractable water source. The temporal placement of the water probe within the reinforcement cycle was varied sequentially, in steps of 16 s. Although the lever-pressing pattern was modulated by the intercalated water probe, water consumption during the probe itself was a decreasing function of time from the following reinforcer. These results were interpreted as evidence against the notion that schedule-induced drinking is a "ubiquitous" phenomenon and are congruent with results from other "intruded stimulus" experiments.  相似文献   
800.
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