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A multitrait-multimethod (MTMM) matrix was used to evaluate validity evidence for a digital image manipulation (DIM) body image measurement technique in young women. One hundred one young women completed the DIM procedure and the Thompson and Gray (1995) Contour Drawing Rating Scale to measure self-ideal discrepancy and size perception accuracy components of body image. Seven-day test-retest reliability was acceptable (R = .81-.95). Convergent validity for self-ideal discrepancy was higher (r = .74) than the corresponding heterotrait, monomethod coefficients (r = .46, r = .23) and heterotrait-heteromethod coefficients (r = .18, r = .12). However, the convergent validity coefficient for size perception accuracy was r = .12. The pattern of correlations in the MTMM matrix met the criteria of Campbell and Fiske (1959) for validity of these procedures to measure self-ideal discrepancy but not size perception accuracy. The DIM procedure addresses some of the criticisms associated with figure-rating scales, such as unrepresentativeness of the figures, scale coarseness, and restriction of range in responses. DIM, therefore, represents a realistic, valid alternative to figure-rating scales for measuring self-ideal discrepancy.  相似文献   
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Cells and cell-free solutions of the culture filtrate of the bacterial symbiont, Xenorhabdus nematophila taken from the entomopathogenic nematode Steinernema carpocapsae in aqueous broth suspensions were lethal to larvae of the diamondback moth Plutella xylostella. Their application on leaves of Chinese cabbage indicated that the cells can penetrate into the insects in the absence of the nematode vector. Cell-free solutions containing metabolites were also proved as effective as bacterial cells suspension. The application of aqueous suspensions of cells of X. nematophila or solutions containing its toxic metabolites to the leaves represents a possible new strategy for controlling insect pests on foliage.  相似文献   
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This article develops a theoretical context for the influence of personality traits on commenting behaviors on online news Web sites. Drawing on the literature of personality, and online behaviors, we examine how personality traits may influence which individuals make contributions on news Web sites. Additionally the article focuses on how the commenting “landscape,” in particular moderation policies and user interfaces, may impact those who contribute.  相似文献   
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INTRODUCTION Pasteuria penetrans is an obligate, en-dospore-forming bacterial parasite of Meloidogynespp. and has shown potential as a biological controlagent against root-knot nematodes (Chen et al., 1996;Dickson et al., 1994) in pot experiments (Channer andGowen, 1988) and micro-plot experiments (Daudi etal., 1990; Trivino and Gowen, 1996). There are prac-tical and technical problems associated with massproduction of P. penetrans inoculum. In-vivo systems,although proven (Stirling an…  相似文献   
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The purpose of this study was to demonstrate the bias in the Bland-Altman (BA) limits of agreement method when it is used to validate regression models. Data from 1,158 men were used to develop three regression equations to estimate maximum oxygen uptake (R2 = .40, .61, and .82, respectively). The equations were evaluated in a cross-validation sample of 581 men. The BA means and differences were correlated (p < .001) in the cross-validation sample for each model (r = .55, .39, and .26, respectively), thus demonstrating bias. The BA method is inappropriate for validation of regression models. Validation of regression equations is properly conducted by plotting the residuals against the estimated values and examining the magnitude of the estimation error.  相似文献   
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The definition of poverty in terms of adequacy of income orexpenditures is not conducive to analysis of time-trends inpoverty, because it is too expensive to survey income or expendituresfrequently. On the other hand, the poverty-self-rating approachis an economical means of generating a time-series. The bottom-upperspective on poverty is socially meaningful in itself, irrespectiveof its correlation with poverty measured from the top down.Unlike official poverty lines, poverty thresholds obtained bythe self-rating approach are not institutionlly manipulable.Cross-sectionally, the Philippine data on self-rated povertyand self-rated poverty lines have familiar economic-demographiccharacteristics. Use of the self-rating approach in the Philippinessince 1981, enabling poverty to be surveyed very many times,shows that poverty has been quite volatile. In contrast, theofficial series on poverty has only three data points (1985,1988, and 1991) within that period. Regression analysis attributesthe volatility in self-rated poverty during 1981–92 mainlyto changes in the inflation rate, and secondly to changes inthe unemployment rate. Changes in per capita income, however,were not significant in explaining changes in the level of poverty.  相似文献   
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INTRODUCTION Entomopathogenic nematodes of the generaSteinernema and Heterorhabditis have been used tocontrol a wide range of agriculturally important insectpests (Kaya and Gaugler, 1993). The mechanism bywhich these nematodes are able to infect and repro-duce in the insect host involves a mutual relationshipbetween the nematode and the symbiotic bacteria,Xenorhabdus spp. and Photorhabdus spp. (Akhurstand Dunphy, 1993; Forst and Nealson, 1996). Poinarand Thomas (1966) established tha…  相似文献   
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Purpose: To develop models to estimate aerobic fitness (VO2max) from PACER performance in 10- to 18-year-old youth, with and without body mass index (BMI) as a predictor. Method: Youth (= 280) completed the PACER and a maximal treadmill test to assess VO2max. Validation and cross-validation groups were randomly formed to develop and examine accuracy of models. Participants were classified into FitnessGram® Healthy Fitness Zone categories based on measured and estimated VO2max and criterion-referenced validity was evaluated. Results: Multiple correlations between measured and estimated VO2max ranged from .70 to .73, with standard errors of estimate between 6.43 and 6.68 mL·kg?1·min?1. Accuracy with and without BMI was nearly identical. Overall, criterion-referenced validity evidence was moderate. Conclusion: Moderately accurate and feasible models were developed. Minimal improvement in accuracy was noted when BMI was added as a predictor. The model with PACER and age as predictors has a high level of utility for youth fitness testing.  相似文献   
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