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Pigeons were trained to match the number of responses made during a production phase to the number of keylight flashes (2, 4, or 6) in a previous sample phase. In Experiment 1, there were 2 conditions in which the flashes were programmed to occur at a constant rate or within a constant overall duration. For both conditions, although accuracy was relatively low, responding increased linearly with flash number and coefficients of variation decreased. Positive transfer to novel numbers was obtained only when test and baseline trials had the same temporal organization, but multiple regressions revealed significant control by number independently of temporal cues. In Experiment 2, flashes were programmed to occur pseudorandomly to degrade the validity of temporal cues. Results were similar to in Experiment 1. A prototype response class model accounted for the major features of the data. According to the model, responses during the production phase are shaped into higher order units that are associated with different stimulus numbers and function as a rough category scale of numerosity.  相似文献   
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There are strong social pressures for U.S. females, particularly those of European heritage, to achieve and maintain an extremely low body weight. These pressures are reflected in a variety of media sources, including advertising. We argue that valuing thinness, exposure to thinness-depicting media, and lacking skepticism about tobacco advertisements have adverse effects on young women's decisions about smoking, particularly smoking for weight control. We tested these hypotheses in a study of 188 female undergraduates, both never-smokers and daily smokers. Believing that smoking controls weight, exposure to thinness-depicting media, and low levels of skepticism about tobacco advertising were associated with being a smoker. Among smokers, believing that smoking controls weight, internalizing thinness pressures, and low levels of feminist consciousness were associated with smoking for weight control. Results are discussed with the aim of encouraging public health anti-smoking campaigns targeted at women, and smoking cessation programs that are responsive to the needs of weight-concerned female smokers.  相似文献   
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Lawton  Carol A. 《Sex roles》2001,44(5-6):321-337
This study examined gender and regional differences in spatial referents used in giving route directions. In response to an Internet survey, participants (primarily white and highly educated) provided samples of route directions to a target destination in their home area. Only directions from those living in the United States were analyzed. Women referred more often than men to buildings as landmarks, whereas men referred more often than women to cardinal directions. Both women and men referred more often to cardinal directions if they reported that they lived in the Midwest/West than in the Northeast/South, or if they lived in areas where the roads were arranged in a gridlike pattern. The findings suggest that women and men differ in the type of spatial referents they use in giving directions, but that direction giving in both genders is affected by the environment in which they live.  相似文献   
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This is a report of the preliminary findings of a brief exploratory ethnographic study in a cancer diagnosis and treatment clinic. The main research purpose was to explore the meaning of cancer and cancer treatment to patients themselves and to their relatives and close friends. The methods are described in detail in a paper focusing on the experiences of being a novice ethnographer (Peters et al. (2001) J Genet Counsel 10(2):133–150.). The preliminary results of this exploratory fieldwork indicate that the experience of attending a cancer treatment clinic for evaluation and/or treatment is a complex social, emotional as well as medical process for patients and families. Themes with relevance to genetic counselors that emerged from this early observation period included ideas about causes of cancer, the complex nature of families and kinship, coping and support, use of food, and healing. These initial findings have implications for genetic counseling practice and hopefully will stimulate more qualitative social and behavioral research in cancer genetic counseling.  相似文献   
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The WATCH (Wellness for African Americans Through Churches) Project was a randomized trial comparing the effectiveness of 2 strategies to promote colorectal cancer preventive behaviors among 587 African American members of 12 rural North Carolina churches. Using a 2 X 2 factorial research design, the authors compared a tailored print and video (TPV) intervention, consisting of 4 individually tailored newsletters and targeted videotapes, with a lay health advisor (LHA) intervention. Results showed that the TPV intervention significantly improved (p <.05) fruit and vegetable consumption (0.6 servings) and recreational physical activity (2.5 metabolic task equivalents per hour) and, among those 50 and older (n = 287), achieved a 15% increase in fecal occult blood testing screening (p =.08). The LHA intervention did not prove effective, possibly because of suboptimal reach and diffusion.  相似文献   
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Persistent symptoms of nausea, distress, and vomiting triggered by reminders of cancer treatment were examined among 273 Hodgkin's disease survivors, 1 to 20 years posttreatment. Prevalence rates were high for distress and nausea but low for vomiting. Retrospective report of anticipatory symptoms during treatment was the strongest predictor of persistent symptoms, suggesting that treatment-induced symptoms are less likely to persist if conditioning does not occur initially. Time since treatment was also a significant predictor, with patients more recently treated more likely to experience persistent symptoms. Thus, an explanatory model based on classical conditioning theory successfully predicted presence of persistent symptoms. Symptoms also were associated with ongoing psychological distress, suggesting that quality of life is diminished among survivors with persistent symptoms. Recommendations for prevention and treatment of symptoms are discussed.  相似文献   
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