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31.
Three experiments with rats (Rattus norvegicus) were conducted to examine the roles of the male's penile spines and penile cups (flaring of the distal glans) in the induction of luteal activity in the female, and in the removal of copulatory plugs from the vaginal tract. The results of Experiment 1 revealed no role for the cup in luteal induction but did suggest that elements of the ejaculatory reflex apart from cup formation contribute to the elicitation of this neuroendocrine response. The origin of this stimulatory effect was not directly determined, but indirect evidence suggested a role for penile spines. In Experiments 2 and 3, features of the glans penis that might help effect plug removal were investigated, and the experiments demonstrated that penile spines, perhaps in conjunction with penile cups, contribute to the extraction of plugs from the vagina.  相似文献   
32.
The purpose of the present study was to evaluate the predictive validity of the Yellow Brick Road Test (YBRT) relative to performance in reading as measured by the Metropolitan Achievement Test (MAT). A full prediction-performance comparison matrix was employed to compare three different cutoff scores for the YBRT for the identification of “at-risk” children. Four hundred and fourteen kindergarten-aged children were administered the YBRT, 214 of whom were followed to the end of second grade. It was concluded that the YBRT is a moderately valid instrument for predicting the level of reading achievement in a population with a different average performance level from the normative sample. However, the results of this study failed to support the utility of the test author's suggested use of a score of 120 as the cutoff score. Finally, it is recommended that a prediction-performance comparison study be considered standard methodology for the evaluation of the validity and efficiency of screening instruments.  相似文献   
33.
The written transmission of therapists' expertise in manuals is an important issue which is highlighted in the literature. Manuals are essential for research, training and therapeutic guidance. However, the conceptualisation, design and drafting of therapy manuals have received little attention. Our team conceptualised and designed a 10-monthly session multi-family therapy programme for adolescents suffering from anorexia nervosa. This paper presents the methodology used to evolve from training and theoretical models to designing a programme and drafting the accompanying manual. We then describe how our team reached a consensus regarding the role to be attributed to food-related symptoms in the programme. These arduous tasks were rewarded by fruitful discussions among team members, which led to a shared theory of treatment. The methodology presented here is drawn from both the experience of specialised teams and from that of families in providing care to adolescents with anorexia nervosa.  相似文献   
34.
Cultures responded to the COVID-19 pandemic differently. We investigated cultural differences in mental health during the pandemic. We found regional differences in people's reports of anxiety in China over two years from 2020 to 2021 (N = 1186). People in areas with a history of rice farming reported more anxiety than people in wheat-farming areas. Next, we explored more proximal mechanisms that could help link the distal, historical factor of rice farming to people's modern experience of anxiety. Rice areas scored higher on collectivism and tight social norms than wheat areas, and collectivism, rather than norm tightness, mediated the rice-anxiety relationship. These findings advance our understanding of the distal sources of cultural differences, the proximal mechanisms, and mental health problems during the pandemics.  相似文献   
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The paper describes a method of constructing Latin-square designs in which treatment sequences are unbiased with regard to serial order as well as position of treatment. The procedure is useful for those Latin squares in which the number of cells in each column (or row) is an even number, which, when written in ascending and descending series, contain corresponding ordered numbers prime to each other. Such numbers are 2, 4, 6, 10, 12, 16, 18, 22, 28, 30, 36, etc.  相似文献   
37.
Geometrical properties and relationships of the Doolittle and square root methods of multiple correlation, as represented in the variable subspace of an orthogonal person space, are shown. The method of representation is also useful for depicting zero-order and partial correlations, as well as for the more general problem of the combination of variables.  相似文献   
38.
The Doolittle, Wherry-Doolittle, and Summerfield-Lubin methods of multiple correlation are compared theoretically as well as by an application in which a set of predictors is selected. Wherry's method and the Summerfield-Lubin method are shown to be equivalent; the relationship of these methods to the Doolittle method is indicated. The Summerfield-Lubin method, because of its compactness and ease of computation, and because of the meaningfulness of the interim computational values, is recommended as a convenient least squares method of multiple correlation and predictor selection.  相似文献   
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The present research investigates the relationships between demographic characteristics and employees' perceptions of appropriate pay-differentials (APD's). In order to investigate this relationship, we examined organizations in two different countries with different social philosophies. The dependent variable (APD's) is defined as what is felt and/or perceived by the individual to be the appropriate pay-differentials among positions with different responsibilities and at different organizational levels. Two different subject groups were used: 137 salaried employees from an automotive engineering company in the U.S.A., and 107 salaried employees from an engineering company in Sweden. Questionnaires constructed in English and Swedish included: (1) questions about individual demographics; (2) job factors; and (3) perception of appropriate pay-differentials using eight organizational charts. Results indicated that the influence of social philosophy, as expressed by organizational socialization processes, was limited in scope. Individual differences associated with employees' perceptions of appropriate pay-differentials should be taken into account when determining pay and compensation policies. These considerations may encourage employee participation in decision making and lead to better organizational outcomes.deceased.  相似文献   
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