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151.
The human immunodeficiency virus (HIV) causes a chronic, progressive, immune deficiency disease, the most severe phase of which is Acquired Immune Deficiency Syndrome (AIDS). HIV is a newly characterized human retrovirus transmitted only by direct exposure to blood or blood derivatives, certain acts of sexual intercourse, or transfer from infected mother to fetus or infant. In this article the author reviews the most important current epidemiologic, clinical, and virologic information about HIV and HIV disease and provides a factual framework for understanding the issues created by the epidemic.  相似文献   
152.
In this study the authors investigated the relationship between the Male Role Norm Scales (MRNS; Thompson & Pleck, 1987) and gender-related attitudes and behaviors in a sample of 367 male counselors drawn from American Counseling Association (ACA), formerly the American Association for Counseling and Development (AACD), members. Results indicated that this group of men did not, in general, endorse traditional male roles as measured by the MRNS. When a degree of affiliation with these roles was found, however, it was predictive of violence proneness, intimacy style, and degree of perceived similarity to father. Implications for training and counseling are discussed.  相似文献   
153.
This study investigated the psychological and physical health status of 265 crew members on two U.S. Navy ships (a guided missile cruiser and a frigate on convoy escort duty for tankers under U.S. flag) during the Persian Gulf conflict at four time periods during combat-ready operations on a single day. Findings suggest that adaptation occurs to extreme stressors associated with sustained operations. Suggestions are made relative to measures that may minimize psychological and physical conditions that adversely affect performance under conditions of heavy stress. Report No. 89-18, supported by the Naval Medical Research and Development Command, Bethesda MD, Department of the Navy, under research Work Unit No. 63206N.M0096. The opinions expressed in this paper are those of the author and do not reflect the official policy or position of the Department of the Navy, Department of Defense, nor the U.S. Government.  相似文献   
154.
Personnel Reaction Blank (PRB) scores and biographical data were obtained from two groups of registered nurses; a deviant group, represented by those who had official actions taken against their nursing license by the Minnesota Board of Nursing (n=53) and a non-deviant group of nurses (n=79) randomly selected from a broader population. The hypothesis that the deviant group of nurses would exhibit lower PRB scores, on average, compared to the non-deviant group was confirmed. The mean PRB scores for the deviant nurses (m=32.43) were significantly lower (p.01) than for the randomly selected non-deviant nurses (m=35.06). A multiple regression logit analysis showed that in addition to PRB scores, college degree, sex, and household income variables were also significantly related (p.001) to deviant and non-deviant group assignment; nonetheless, PRB significantly differentiated these groups after holding these variables constant.This study is based on the Masters thesis research of the first author. We acknowledge the help of the study subjects who contributed their time and effort.  相似文献   
155.
Naturalistic research methods were used in this study to collect the voices, ideas, and opinions of rural, working poor, Appalachian families from Southeast Ohio about the stress of poverty in family life and family coping in the face of poverty. This data should be of interest to the professional family therapist who practices with the working poor.  相似文献   
156.
The current study tests for the presence of differential order effects in evaluation tasks with consistent and inconsistent evidence as predicted by the Hogarth and Einhorn (1992) belief-adjustment model. The results, based on both between-subjects and within-subjects experiments, demonstrate that there were significant recency effects with inconsistent evidence as predicted, larger recency effects when the inconsistent evidence was farther apart in subjective value as predicted, and significant recency effects even when subjects were given training designed to both help them understand the task as completely as possible and to be better able to assess the pieces of evidence. By including a within-subjects design, we were able to demonstrate that the difference in subjective value between two pieces of evidence is the primary factor influencing the magnitude of the recency effect, regardless of whether the evidence is consistent or inconsistent. This latter finding is unique and contrary to previous research and theory.  相似文献   
157.
Five questions concerning the properties of spatial representations are explored. (1) How accurately does a spatial representation correspond to the true scene? (2) If inaccurate, how does it differ? (3) Are representations of a familiar scene more accurate than those of an unfamiliar one? (4) Do representations of a scene currently in view differ from those retained in memory? (5) Do the representations of the blind have properties comparable to those-of the sighted? Seven sighted and 7 highly mobile blind subjects, all familiar with a room, and 6 sighted subjects unfamiliar with it, were asked to estimate the absolute distances between 10 salient objects in the room. The 14 familiar subjects made their estimates twice: while they were in the room, and while they were remote from it. Regression analyses showed that the estimates of all subjects had strong metric properties, being linearly related to true distance, with a true zero point; and multidimensional scaling showed that all subjects produced distance estimates that could be scaled in two dimensions to closely match the actual locations of the objects. Familiarity had no effect. The effect of location of testing was the same for both the sighted and the blind: all subjects displayed better spatial knowledge when tested in the room; and all subjects underestimated true distance substantially when tested out of the room. The results showed no qualitative differences as a function of blindness, at least for these highly skilled blind travelers.  相似文献   
158.
159.
Previous studies of infants’ ability to integrate and to utilize relative motion as information for form in the absence of structural cues have primarily involved motions that are uniform in rate, direction, and path within the form to be constructed. In the present study, we examined infants’ ability to integrate relative motion information from motions that are nonuniform along these dimensions, and from this integrative process to construct a coherently rotating two-dimensional form. Infants’ ability to integrate nonuniform motion was measured with regard to their ability to discriminate the rotating form from a noncoherent control display containing the same absolute motions. The results showed that discrimination of the coherent and incoherent displays was not demonstrated until 7 months of age. Two additional experiments were conducted to rule out the possibility that this discrimination was based on the detection of local regions of coherence, rather than the perception of the global rotating form. In both experiments, the results did not support discrimination based exclusively on local cues alone. From the combined results of all three experiments, we conclude that infants demonstrate the capacity to integrate the information contained within nonuniform trajectories into a coherent structure by 7 months of age.  相似文献   
160.
The perception of continuously repeating auditory patterns by European starlings was explored in seven experiments. In Experiment 1, 4 starlings learned to discriminate between two continuously repeating, eight-element, auditory patterns. Each eight-element pattern was constructed from different temporal organizations of two elements differing in timbre. In Experiments 2–7, the repeating patterns were transformed in ways designed to identify the starlings’ perceptual organization of the patterns. In Experiment 2, the starlings identified patterns beginning with novel starting points. In Experiment 3, discrimination performance was adversely affected by reorganizing the elements in the patterns. In Experiments 4 and 5, the pattern elements were altered. In Experiment 4, the patterns were constructed from two novel elements. In Experiment 5, the temporal location of the two pattern elements was reversed. The transformations of the patterns in Experiments 4 and 5 affected discrimination performance for some, but not all, of the starlings. In Experiments 6 and 7, replacing either of the two elements with silent intervals had no effect on discrimination performance. The results of these experiments identify basic grouping principles that starlings use when they perceive auditory patterns.  相似文献   
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