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971.
Principally new, simple and objective method for investigation of human hair density is suggested. Hair identity in relation to a concrete person can be confirmed or excluded by statistical processing of the results obtained.  相似文献   
972.
Flowers ofMelandrium album are frequently pollinated byCucullia umbratica L. This heavy moth always lands on the flowers. The process of insertion of the proboscis and the drinking thereafter is described. From experiments it is concluded that senses for perception of the relative humidity of the air are located on the antennae. The moth is able to locate flowers by smell only, but visual orientation seems to be more predominant. Legs and antennae possess contact chemoreceptors, sensitive to sucrose and to chemicals present on the surface ofM. album flowers. The moth responds after contact of the legs with petal lobes ofM. album by extension of the proboscis. Inserting behaviour follows only after contact of the proboscis tip with the ligula. The moth appears to be a specialised flower visitor.
Resume Les fleurs deMelandrium album sont polinisées parCucullia umbratica qui butine ces fleurs après s'y être posé. Les expériences rapportées ici témoignent que des organes sensoriels aptes à percevoir l'humidité de l'air sont localisés sur les antennes. Le papillon peut localiser les fleurs par simple odeur mais l'orientation visuelle semble prédominante. Les pattes et les antennes possèdent des chemorécepteurs de contact, sensibles au sucrose et aux composés chimiques associés aux fleurs deM. album. Le papillon, après contact de ses pattes avec les pétales de cette fleur manifeste une extension de son proboscis et ce n'est qu'après contact de ce dernier avec la ligula, que se réalise l'insertion dans la corolle. Ce papillon semble être spécialisé comme visiteur de fleurs.
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Ideographic representations (schematic drawings) are useful for analyzing and communicating complex ideas. They constitute simplified versions of the way multiple and diverse elements, concepts, and variables interact according to each author's conceptions, knowledge, and experience of planned change and change phenomena. Such representations depict a sense of order under a particular model configuration or system notion, involving contexts where action takes place and events occur. This paper is based on the commonality analysis of 46 models related to technology transfer. Within the framework of previously published research, complementary findings are presented here. The discussion is focused on the characteristics of the models' contexts, appealing to some technology transfer aspects widely omitted or neglected. It is suggested that the understanding of intervention contextual domains is important to formulate and implement better technology transfer models.  相似文献   
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The Pittsburgh Youth Study is a prospective longitudinal survey of three samples of Pittsburgh boys (each containing about 500 boys) initially studied in first, fourth, and seventh grades. The first two data collection waves yielded self-reported delinquency and combined delinquency seriousness scores (the combined scores based on information from boy, mother, and teacher) for the middle sample (up to an average age of 10.7 years) and oldest sample (up to an average age of 13.9 years). These scores were compared with records of petitions to the Allegheny County Juvenile Court for delinquency offenses before and up to six years after the assessments. The area under the ROC curve was used as a measure of validity. Concurrent validity was higher than predictive validity. The combined scale had similar concurrent validity but greater predictive validity than the self-report scale, and the combined scale also identified a greater number of boys as serious delinquents. Concurrent validity for admitting offenses was higher for Caucasians, but concurrent validity for admitting arrests was higher for African-Americans. There were no consistent ethnic differences in predictive validity. There was an increase in predictive validity, for both African-Americans and Caucasians, by combining self-report data with information from other sources. Afrer controlling for delinquency measures, African-Americans were more likely than Caucasians to be petitioned in the future, but not in the past. In this research, ethnic differences in official delinquency were partly attributable to ethnic differences in delinquent behavior and were not attributable to differential ethnic attrition or differential ethnic validity of measures of delinquent behavior.  相似文献   
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