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131.
Many young children are reared today in both family and child-care settings. The relation that exists between these two settings has important implications for child care. Bronfenbrenner's (1979) ecological model is used as a way to view the interrelations among children, families, and child-care programs. Data from a study of infants in day care provide information on the time infants spend in family and day-care contexts, how parents and caregivers view children's behavior in these two settings, and rates of otitis media (ear infections) and other illnesses for these children. Results show that infants spend about twice as many hours per day awake with parents as in day care. Regarding child behaviors, parents and caregivers seem to have similar behaviors they like and dislike, but they each see particular children quite differently with respect to these behaviors. Finally, infants in this sample were diagnosed with illnesses 60% to 70% of the time. Findings are discussed in terms of the ecological model with particular attention given to relations between parents and caregivers.  相似文献   
132.
Mary E. Yepez 《Sex roles》1994,30(1-2):121-133
For the most part, gender-differentiated teacher behavior in English as a Second Language classrooms in the United States has not been examined. Does the preference for male students demonstrated by both male and female teachers in American classrooms (Sadker et. al., 1992) also occur in ESL classrooms? If so, are ESL teachers aware they show such bias? To find out, the author observed and evaluated, both quantitatively and qualitatively, classroom interactions of four ESL teachers. The teachers, two males and two females, were white, American-born, and had finished graduate studies. All but one of the ESL teachers observed showed remarkable equality in their classroom interactions with the genders. The results are discussed, and future research directions proposed.  相似文献   
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134.
During sensory preconditioning, rats were given two distinct flavors (saccharin and coffee) in sequence with 0, 9, or 27 sec between the two flavors. A control group received the flavors unpaired. In subsequent training, the second flavor preceded sucrose by 5 min. Later, the subjects that had had 0- or 9-sec delays between the two flavors showed a significant preference for the flavor not directly reinforced, whereas those that had had a 27-sec delay showed only a marginally significant preference. Although taste aversions have been produced using these methods, this is the first demonstration of conditioned preferences for flavors not directly associated with the reinforcers. These results offer an alternative way to study flavor-flavor learning.  相似文献   
135.
This paper reports on the reliability of children's responses on the Child and Adolescent Services Assessment (CASA) — a self-report instrument for use with 8– to 18-year-olds that gathers information about services used to address mental health problems. Findings were based on interviews completed by 77 children at a one week test-retest interval. Results showed that reports of lifetime service use were as reliable as were reports of service use in the preceding three months. Children reported restrictive and intrusive services more reliably than services that were provided in their natural environment. Reliability appeared to be associated more strongly with characteristics of the type of service than with characteristics of the child. Children also could report reliably on some details about their encounters with service providers (e.g., length of stay, number of visits, and onset of service use).  相似文献   
136.
Research on risk-taking behavior has shown to yield inconsistent findings. Three studies were conducted using four different analysis techniques. The first study used a phenomenological approach and qualitative analysis to gain an understanding of risk-taking. A model of factors relating to risk-taking was developed and tested in a second study. The third study was conducted to develop scales of risk and used magnitude estimation and multidimensional scaling techniques. Results from the studies confirmed the multidimensionality of the construct of risk-taking. Also indicated was a gender difference in risk-taking behavior and perception. These studies expand our knowledge of risk-taking behavior in that 1) a method of categorizing risks was developed, 2) gender similarities and differences in risk-taking were explored, and 3) perceived magnitude and underlying dimensions of risk were developed.  相似文献   
137.
In previous research, replicated here, we found that some object recognition processes influence figure-ground organization. We have proposed that these object recognition processes operate on edges (or contours)detected early in visual processing, rather than on regions. Consistent with this proposal, influences from object recognition on figure-ground organization were previously observed in both pictures and stereograms depicting regions of different luminance, but not in randomdot stereograms, where edges arise late in processing (Peterson & Gibson, 1993). In the present experiments, we examined whether or not two other types of contours—outlines and subjective contours—enable object recognition influences on figure-ground organization. For both types of contours we observed a pattern of effects similar to that originally obtained with luminance edges. The results of these experiments are valuable for distinguishing between alternative views of the mechanisms mediating object recognition influences on figure-ground organization. In addition, in both Experiments 1 and 2, fixated regions were seen as figure longer than nonfixated regions, suggesting that fixation location must be included among the variables relevant to figure-ground organization.  相似文献   
138.
Contrast sensitivity was measured for 12 healthy young males while sober, after ingestion of an alcohol placebo, and after ingestion of alcohol (95% grain alcohol; mean estimated blood alcohol level = .088%). Observations were made for both stationary gratings and gratings that traveled through a circular path and required pursuit eye movements. The significant alcohol-related reduction in contrast sensitivity was 2.6 times greater for moving (.29-log-unit reduction) than for stationary gratings (.11-log-unit reduction). The loss in contrast sensitivity for the moving gratings of high spatial frequency (12 cpd) was particularly severe (.37 log unit). Estimated blood alcohol level was correlated with the loss in contrast sensitivity for moving gratings (r = .61), but not with the loss for stationary gratings. Estimated blood alcohol level was strongly correlated with the difference between the loss in contrast sensitivity to moving and stationary gratings (r = .75). These results are consistent with reports that alcohol consumption degrades the ability to make pursuit eye movements. Subjects’ perceived intoxication level was not a reliable predictor of any index of visual performance.  相似文献   
139.
The present study investigated 2-month-olds’ abilities to discriminate allophonic differences that are potentially useful in segmenting fluent speech. Experiment 1 investigated infants’ sensitivity to the kind of distinction that may signal the presence or absence of a word boundary. When tested with the high-amplitude sucking procedure, infants discriminated pairs of items, such as “nitrate” versus “night rate” and “nikrate” versus “nike rate.” By greatly reducing the potential contribution of prosodic differences to these contrasts, Experiment 2 evaluated whether the allophonic differences for /t/ and /r/ were sufficient for infants to distinguish the “nitrate” versus “night rate” pair. Infants distinguished “nitrate” from a cross-spliced version of “night rate,” which differed only in the allophones for /t/ and /r/ that it included. Thus, infants appear to possess one of the prerequisite capacities (i.e., the ability to discriminate allophonic distinctions) necessary to use allophonic information in segmenting fluent speech.  相似文献   
140.
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