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31.
The development of expert and decision support systems requires the collection, organization, codification, and storage of a body of specialized knowledge. The development, using reconstructive methods, of two such knowledge bases, the first containing the current scientific literature and the second containing an expert’s knowledge, is described for an automated decision support system, the Mental Retardation-Expert. This system provides practitioners with assistance in the treatment of aggressive, self-injurious, and destructive behaviors displayed by individuals with mental retardation or developmental disabilities. The average interobserver reliability of the expert knowledge base ranged from 92.5% to 95.0% when calculated across four clinicians’ assessments of 31 abstracted cases.  相似文献   
32.
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   
33.
Two experiments were conducted to examine the structure of the mental lexicon. A lexical search of American English, using the Brown corpus (Francis and Kucera, 1982), revealed a skewed, frequency-dependent distribution in which the syntactic classes of noun and verb are distinguished in terms of the phonological classification of their vowels. Among high-frequency words, nouns are more likely to have back vowels (57%) rather than front vowels (43%) and verbs more likely to have front vowels (62%) than back vowels (38%). This distribution, however, does not hold for low-frequency nouns and verbs in the language. Noun and verb stimuli containing front and back vowels were examined in both an auditory noun/verb categorization task and an auditory lexical decision task. In general, the phonotactic composition of nouns and verbs in the lexicon was shown to have perceptual consequences. Listeners seem to be differentially sensitive to incoming sound patterns on the basis of distributional properties of the lexicon.These experiments were conducted at the Brown University Phonetics Laboratory. The technical expertise of John Mertus and Andrew Mackie as well as the help of Martha Burton and Annemie Witjes are gratefully acknowledged.  相似文献   
34.
Mutual influencing processes are assumed to be the basic building blocks in establishing parentchild bonding and in influencing cognitive and language behavior. A study by Jasnow and Feldstein (1986) revealed that, within the temporal domain of speech, preverbal (9-month-old) infants and their mothers exhibit a pattern of mutual influence (attunement) in their average durations of switching pauses. The general purpose of this research was to extend those findings to children with higher verbal functioning. In addition, parent and child genders, nature of the interaction, and specific aspects of parents' personalities, expressiveness, and instrumentality were considered. Each parent interacted with their 4-or 5-year-old son or daughter in each of two conversations—unstructured (social conversation) and structured (task activity). Conversations were processed by an automated computer system yielding objective measure of turns, vocalizations, pauses, and switching-pause durations. To examine interspeaker influence or attunement of temporal speech patterns, influence coefficients were computer for each speaker on a turn-by-turn basis using time series regression. Analysis of these coefficients revealed that: (1) Mutual influence is most evident with switching-pause duration. (2) Structure in the conversation (as defined by the task or parental instrumentality) seems to facilitate attunement for vocalization and switching pause duration. (3) Attunement with girls seems to occur equally well with both parents, while boys exhibit a style of temporal patterning influence which suggests greater identification with the father. (4) Expressiveness seems to facilitate attunement to the child's switching-pause duration.  相似文献   
35.
Multidimensional scaling (MDS) was used to compare perceptual maps for 10 synthetic English vowels in humans and Old World monkeys (Macaca fuscata andCercopithecus albogularis). Subjects discriminated among the vowels using a repeating background procedure, and reaction times were submitted to an MDS analysis to derive measures of perceived similarity. The dimensions that emerged related to the frequencies of the first(F1), second(F2), and third(F3) formants. Human data indicated a good match to previous MDS studies using rating procedures or confusion matrices: The dominant dimension mapped onto vowelF2, the phonetically most important formant, and the second and third dimensions mapped ontoF1 andF3, respectively.For monkeys, equal weightings occurred forF1 andF2, andF3 was not clearly represented. Monkey sensitivity to the formants appeared to relate to formant amplitudes. If monkeys are giving an accurate representation of the psychoacoustic relations among the formants, then our human results suggest that species-specific mechanisms, reflecting the salience of the phonetic feature of advancement, may contribute to vowel coding in humans.  相似文献   
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37.
This study investigates gender similarity in the effects of birth order upon political leadership. Town supervisors were the leaders studied as there are a considerable number of women who attain this level of leadership. Questionnaires about birth order and family size were gained from 66 women who were town supervisors in New York State in 1992, and compared to a randomly selected sample of 57 male town supervisors. It was found that women as well as men town supervisors were more likely to have been first born in their families. However, whereas gender does not apparently influence the relevance of birth order for leadership, it clearly does exert an influence on the level of political leadership attained. Women town supervisors gained their positions in towns that were considerably smaller than the towns led by the male supervisors. Discussion concerned the nature of family experiences that contribute to leadership training, including those that may be different for girls and boys. Further research is needed to clarify barriers to female assertion of political leadership at more senior levels, because as this study shows, female leadership is being trained in families.  相似文献   
38.
Procurement of organs from non-heart-beating cadaver donors raises concerns. Standards for optimal patient care during withdrawal of life-sustaining therapy are evolving and continue to be debated and studied. Consensus on specific procedures and methods has not been attained, however, and protocols for the procurement of organs from patients following the withdrawal of life-sustaining therapies may compromise the evolving standards and harm the patient and the attendant family. In addition, there is little evidence to suggest that such protocols will significantly increase the number of organs procured. "Non-heart-beating cadaver" protocols that do not give comprehensive attention to optimal patient/family care at the time of withdrawal of life-sustaining therapy ought not to be endorsed.  相似文献   
39.
Presented the 6-month follow-up findings of an experimental intervention designed to provide postshelter advocacy services to women with abusive partners. The intervention involved randomly assigning half the research participants to receive the free services of an advocate, 4 to 6 hours per week, for the first 10 weeks postshelter. One hundred forty-one battered women were interviewed about their experiences immediately upon their exit from a domestic violence shelter: 95% of the sample were interviewed 10 weeks thereafter (postintervention), and 93% were successfully tracked and interviewed 6 months later. At the 6-month follow-up, participants in both groups reported increased social support, increased quality of life, less depression, less emotional attachment to their assailants, and an increased sense of personal power. Although women in both groups reported some decrease in physical abuse over time, there were no statistically significant differences between those with and those without advocates, and abuse continued to be a problem for many women. Those who were still involved with their assailants continued to experience higher levels of abuse and had been more economically dependent upon the men prior to entering the shelter. Women who had worked with advocates continued to report being more satisfied with their overall quality of life than did the women in the control group. The authors thank the Editor and anonymous reviewers for their helpful comments. Thanks also to all present and past staff of the Community Advocacy Project, who helped in data collection and analyses. This work was supported by National Institute of Mental Health Grant 1R01 MH 44849.  相似文献   
40.
MENSTRUAL JOY The Construct and Its Consequences   总被引:1,自引:0,他引:1  
Fifty female college students participated in a study of women's health. In a counterbalanced design, half of the participants completed the Menstrual Joy Questionnaire (MJQ) and the Menstrual Attitude Questionnaire (MAQ) in the first testing session. A week later they completed the Menstrual Distress Questionnaire (MDQ) and the Menstrual Attitude Questionnaire. The other participants completed the MDQ and MAQ in the first session and the MJQ and MAQ in the second. A multivariate analysis of variance revealed that those who received the MJQ first reported more positive cyclic changes on the MDQ and more positive attitudes on the MAQ. A follow-up study of 40 college students examined their responses to the MJQ. Participants reported that they were surprised or incredulous; most had not previously considered positive aspects of the menstrual cycle. Thirty percent reported that the MJQ had caused them to look at menstruation in a different way.  相似文献   
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