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161.
Developmental sequence, relative timing, center of gravity, and phase-plane analyses were used to study a minimum of 15 years of longitudinal, filmed data on the development of hopping in 7 children. The developmental sequences revealed common, qualitative changes in the movement of the children, although each child progressed through the changes at his/her own rate. The timing analyses showed that, in the advanced hop, the tightest limb relationships were found within the hopping leg, then between contralateral limbs of the same girdle, and then between legs and arms. Relative-timing calculations revealed (a) intralimb, timing invariances that were present in first attempts to perform the skill at age 3 and remained for 15 years across all developmental levels; (b) emergent, interlimb timings that gradually became invariant; and (c) intra- and interlimb timing showing gradual development over the 15 years. One invariant, the time between landing and deepest knee flexion, is also invariant in the walk and the run (Shapiro, Zernicke, Gregor, & Diestel, 1981). Phase plane analyses indicated that the timing of peak and zero velocities may be the coordinative constant accounting for a relative timing invariance between the two legs. Position of the body's center of gravity may explain the invariant relative time between landing and deepest knee flexion, or the explanation could lie in the "equation of constraint" regulating joint equilibrium points. The data suggest that modeling the developing hop as the evolving interaction of four vibratory systems would be promising.  相似文献   
162.
163.
The addition of job-related information regarding an applicant's leadership ability reduced bias against female applicants applying for a managerial position.  相似文献   
164.
Children's perception of scale and contour in melodies was investigated in five studies. Experimental tasks included judging transposed renditions of melodies (Studies 1 and 3), discriminating between transposed renditions of a melody (Study 2), judging contour-preserving transformations of melodies (Study 4), and judging similarity to a familiar target melody of transformations preserving rhythm or rhythm and contour (Study 5). The first and second studies showed that young children detect key transposition changes even in familiar melodies and they perceive similarity over key transpositions even in unfamiliar melodies. Young children also are sensitive to melodic contour over transformations that preserve it (Study 5), yet they distinguish spontaneously between melodies with the same contour and different intervals (Study 4). The key distance effect reported in the literature did not occur in the tasks of this investigation (Studies 1 and 3), and it may be apparent only for melodies shorter or more impoverished than those used here.  相似文献   
165.
Evidence increasingly links a high-fat, low-fiber diet to coronary heart disease and certain site cancers, indicating a need for large-scale dietary change. Studies showing the effectiveness of particular procedures in specific settings are important at this point. The present study, using an A-B-A-B design and sales data from computerized cash registers, replicated and extended previous work by showing that inexpensive prompts (i.e., signs and fliers) in a national fast-food restaurant could increase the sales of salads, a low-fat, high-fiber menu selection. Suggestions also are made pertinent to more widespread use of the procedures.  相似文献   
166.
This study investigated the effect of television food commercials on children's self-control within a resistance to temptation paradigm. Commercial type, food stimulus type, and the child's sex provided the three independent variables in a 4 × 4 × 2 factorial design. Behavioral and self-report indices of temptation and control were measured. Children were significantly more tempted to transgress for the low-nutrition food, regardless of the commercial shown. Sex differences in reported degree of temptation were found. However, the television commercials did not affect the children's latency to transgress.  相似文献   
167.
Celiac-Sprue Disease, also referred to as Non-Tropical Sprue, is a dietary disease. Celiac-Sprue patients were asked to complete a questionnaire regarding the effect of dietary restrictions on participation in the Passover meal and reception of Communion. A pilot study suggested that subjects made changes in their religious practices because of dietary restrictions. A second, more detailed survey, was performed in which 58 subjects participated and 14 religions were represented. The results indicated that many subjects made changes in their religious practices (p less than .01), made changes on their own initiative (p less than .01), or violated diet prescribed for the disease under the religious setting versus other settings (p less than .05).  相似文献   
168.
In this study I explored whether the degree of anticipation/habituation (undershooting/overshooting) varies with the dimension to be localized, when the method of adjustment is used in space localization. In this study, undershooting occurred for both the vertical (Group 1) and the horizontal (Group 2) dimensions, but was significant only for verticality. The magnitude of undershooting observed for verticality was significantly greater than that for horizontality. A secondary issue regarding the possible relationship between spatial category width and undershooting/overshooting was examined. It was hypothesized that greater degree of spatial category width would be associated with greater undershooting. The opposite was found: Spatial category width was negatively related to undershooting. Finally, within each group, very high consistency of magnitude of spatial category width was observed (rs greater than .90), despite the fact that spatial category width showed shrinkage over the course of the study.  相似文献   
169.
Tobacco, alcohol, and drug use are problems for American-Indian people. We reviewed these problems and the explanations for them and described a bicultural competence skills approach for preventing substance abuse with American-Indian adolescents. Data from a study of that approach suggest its efficacy with American-Indian youth. At posttest and a 6-month follow-up, American-Indian subjects who received preventive intervention based on bicultural competence skills concepts improved more than did American-Indian subjects in a no-intervention control condition on measures of substance-use knowledge, attitudes, and interactive skills, and on self-reported rates of tobacco, alcohol, and drug use. Our findings have implications for future substance-abuse prevention research with American-Indian people.  相似文献   
170.
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