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951.
A. K. Raychaudhuri 《Resonance》1997,2(12):55-65
In this article we briefly review the application of electrons in the field of microscopy. Two types of microscopes are discussed,
the electron microscope and the tunneling microscope. It is emphasized that in both the applications the electron behaves
as a quantum mechanical object. 相似文献
952.
The Centrality of Test Use and Consequences for Test Validity 总被引:3,自引:0,他引:3
Lorrie A. Shepard 《Educational Measurement》1997,16(2):5-24
What are the origins of consequential validity? What is the role of intended test use in validation? Is the study of unintended effects part of validation? What practical problems does this pose? 相似文献
953.
Robert Wells John McCann Joyce Adams Joan Voris Barbara Dahl 《Child abuse & neglect》1997,21(12):1159-1167
Objective: With the rapid rise of sexual abuse allegations, there is a growing need to develop instruments to help clinicians determine the likelihood that sexual abuse has occurred.Method: This study evaluated the discriminant validity of a structured parent interview regarding emotional, behavioral, and physical symptoms by comparing results among three subsamples of age matched boys: 22 sexually abused boys whose perpetrator confessed, 47 boys evaluated in a sexual abuse clinic but without a history of perpetrator confession and 52 nonabused boys selected after rigorous screening.Results: In comparison with the nonabused (NA) boys, the sexually abused boys were significantly more likely to demonstrate sudden emotional and behavioral changes, frequent stomachaches, more knowledge about sex and sexual activities than expected for age, unusual agressiveness toward playmate or toy's private parts, crying easily, difficulty getting to sleep, and a change to poor school performance. The internal reliability of the SASA was determined to be .83 and scoring of an abbreviated 12-item scale demonstrated a sensitivity of 90.9% and a specificity of 88.5%.Conclusions: The findings suggest that Structured Interview of Symptoms Associated with Sexual Abuse (SASA) is an effective tool which may help in the comprehensive assessment of boys who may have been sexually abused. 相似文献
954.
Yuen Mantak Chung Y. B. Lee Queenie A. Y. Lau Patrick S. Y. Chan Raymond M. C. Gysbers Norman C. Shea Peter M. K. 《International Journal for Educational and Vocational Guidance》2020,20(3):653-676
International Journal for Educational and Vocational Guidance - This study provides insights into how Chinese adolescents in Hong Kong interpret the concept of “meaning in life.” Data... 相似文献
955.
956.
K. P. Mishra A. P. Yadav Lilly Ganju 《Indian journal of clinical biochemistry : IJCB》2012,27(4):357-362
The Antarctic continent on the planet Earth is full of environmental extremes. It is considered as natural stress model. Therefore, the present study examined the effect of harsh environment on the certain salivary markers of 28th Indian Antarctic expeditioners. Thirty healthy men and women (median age 36 year; range 22–61 year) participated in this study. Parameters measured were salivary IgA (SIgA), IgM (SIgM), TGF-β and cortisol level at three different time points: (I) before leaving India on 26th October 2008 for base line level; (II) after 1 month on-board journey on 31st January 2009 in Southern Ocean and (III) after 1 month staying at Maitri, Antarctica on 3rd March 2009. Our observation indicated that Ship borne journey and Antarctic environment increased the SIgA levels while that of SIgM level was not altered on-board but decreased by staying for 1 month at Antarctica. No significant alteration was found in the TGF-β and cortisol level at any point of time. The present study concluded that ship borne journey and Antarctic environment may induce the SIgA level while SIgM level decreased in environmental extremes of Antarctica. 相似文献
957.
958.
959.
Geo.A. Hoadley 《Journal of The Franklin Institute》1935,220(1):134-135
960.
Ordinary and thermal diffusion of moisture in activated alumina are investigated using a new diffusion cell design and scheme of analysis reported earlier. The specific form of the mass flux equation has a pronounced effect on the magnitude of the associated thermal diffusion ratio. In the case of activated alumina-moist air, if a partial pressure gradient is used, then the thermal diffusion term is small if not zero.Free, Knudsen and surface diffusion all play a part in the diffusion through activated alumina. However, surface diffusion makes the major contribution and for this reason the model in this case can be simplified to a two parameter surface model.The activation energy for surface diffusion is constant and is approximately equal to the mean isosteric heat of absorption. In addition, mean pore radius, turtuosity, and other physical constants are computed from the least square fit of experimental data. Furthermore, the model is theoretically consistent over the entire concentration range (0≦ CA ≦ CAsat).A new fact about activated alumina (Grade F1) it that it does not transfer moisture in a nonisothermal condition so long as the partial pressures of moisture on the two sides of the pellet are the same. There appears to be no previous report of this fact in the periodical literature. 相似文献