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National data show a continuing decline in the willingness of people to respond to surveys. This trend is troubling given the central role that survey research plays in collecting data for institutional research purposes. This paper examines the effectiveness of a weighting procedure described by Astin and Molm for adjusting survey results to correct for nonresponse bias. Using data from a Cooperative Institutional Research Program (CIRP) follow-up survey, the results indicate that the weighting procedure is highly effective at reducing nonresponse bias in univariate distributions. The effectiveness of the weighting procedure in adjusting correlation and regression analyses is less clear. This may be due in part to the observation that even when individual variables are noticeably biased, their relationships with each other tend not to be. 相似文献
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The investigation probed relationships among human‐figure drawing, field‐dependent‐independent cognitive style and self‐esteem of 10–15 year olds. It also attempted to predict human‐figure drawing scores of participants based on their field‐dependence‐independence and self‐esteem. Area, stratified and multi‐stage random sampling were used to select a sample of 600 10–15 year olds residing in Kolkata city, India. The sample comprised three age‐based strata: 10 and 11 year olds; 12 and 13 year olds; and 14 and 15 year olds. Each stratum comprised 100 girls and 100 boys. Participants’ actual age‐ranges were 10 years 1 month – 11 years 10 months (first stratum); 12 years 4 months – 13 years 10 months (second stratum); and 14 years 3 months – 15 years 9 months (third stratum). Goodenough‐Harris Drawing Test, Group Embedded Figures Test and Coopersmith Inventory were administered for assessing participants’ human‐figure drawing, field‐dependence‐independence and self‐esteem respectively. Results revealed significant positive relations among pertinent variables. Participants’ human‐figure drawing scores could be significantly predicted by their field‐dependence‐independence and self‐esteem. 相似文献
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Stem cells constitute an important class of cells in the body that have the ability to perpetuate themselves and remain in an uncommitted state by a process of self-renewal as well as to specialize into new cell types. Their ability to differentiate into multiple cell types marks the tremendous potential of stem cells for tissue repair and organ regeneration. Realization of this potential is rapidly opening up unexplored avenues for curing several ailments including diabetes and neurodegenerative diseases. However, very little is understood about the basic biology of stem cells. For example, what are the biochemical tags that allow us to identify stem cell? Which are the signaling pathways that regulate their function? How does the environment (niche) influence major decisions made by stem cell? Is stem cell therapy the end to all woes, or is there a flip side to the story? This article aims to give an overview of the current status of stem cell research and raises some alarming issues related to stem cell-based therapies. 相似文献
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S.K. Dey 《Journal of The Franklin Institute》1979,307(1):21-30
In this paper we attempt to develop the algorithm of PIS (Perturbed Iterative Scheme) in its simplest form, yet retaining its mathematical rigor. Several applications are given and a brief comparison of PIS is made with other methods. The fundamental concept behind PIS is explained. Success of the method is basically for solutions of nonlinear systems. 相似文献
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Bringing the Classroom to the Web: Effects of Using New Technologies to Capture and Deliver Lectures
Technology expands instructional options for faculty, and this study examines the differential learning effects of offering
a lecture on physics to students in a traditional classroom versus internet video formats. Based on an experiment conducted
in a natural educational context, results indicate enhanced transfer of lecture information in the video formats relative
to the live condition, with students also responding more positively to personalized video presentation.
相似文献
Eric L. DeyEmail: |
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Purnima Dey Sarkar G Rajeshwari T. M. Shivaprakash 《Indian journal of clinical biochemistry : IJCB》2005,20(1):139-144
Glomerular filtration rate is routinely assessed by measuring the serum markers such as urea nitrogen and serum creatinine.
Although these markers are widely used to assess renal function but they do not perform optimally in certain clinical settings.
There is thus a practical need for an easily automated alternative to plasma creatine, which would be more specific, sensitive
and reliable from the analytical and clinical view point. Compared with the above endogenous markers, and time consuming laborious
tests, Cystatin C facilitates the recognition of abnormal renal function in children, as its reference range is constant beyond
the 1st year of life. This review mainly focuses on the diagnostic performance of Cystatin C against other renal markers in the pediatric
population and in specific subpopulations of patients. 相似文献
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Newton’s theory of gravitation solvedmany problems of celestialmechanics but led to some major problems, one of which was that it gave rise to a serious paradox discussed in this article. The paradox has a number of manifestations one of which is presented here. It should be remembered that the root cause of all these paradoxes is fundamentally the same. Laplace attempted an ad hoc solution. However, it could not be mathematically demonstrated that his proposal solves the difficulty. In this article, it is shown that his suggestion removes the problem. A physical phenomenon that can justify Laplace’s suggestion is also mentioned briefly. This article also poses an interesting mathematical problem that can be attempted by interested readers. The computational solution is presented here. 相似文献