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61.
Matthew J. Mayhew Tricia A. Seifert Ernest T. Pascarella Thomas F. Nelson Laird Charles F. Blaich 《Research in higher education》2012,53(1):26-46
The purpose of this paper was to determine the effects of deep approaches to learning on the moral reasoning development of
1,457 first-year students across 19 institutions. Results showed a modest positive relationship between our measures of deep
approaches to learning and moral reasoning at the end of the first year of college even after controlling for precollege moral
reasoning. After accounting for a host of demographic and relevant student characteristics and for the natural clustering
of students, we found that the integrative learning subscale, which captures students’ participation in activities designed
to integrate information from varied sources and diverse perspectives, positively affected moral reasoning among first-year
students. Implications for researchers and practitioners are discussed. 相似文献
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Iowa students and parents completed related attitude and belief questionnaires about school subjects. Grade K–3 students received simpler questionnaires than did Grade 4–6 students or parents. Among Grade 4–6 children, girls perceived higher competence in reading than did boys, but boys perceived higher competence in physical science. All children perceived physical science competence lower than reading or math competence. Parents perceived boys as more competent in science. Girls like reading more than boys did; boys and girls did not differ in liking of science. Grade 4–6 children also expected lower grades in and attached lower importance to physical science than to reading. Parents perceived science as more important for boys and expected higher performance of boys. Jobs related to math or science were seen as more male dominated. These results provided a more comprehensive picture of attitudes and beliefs about science in the elementary school than had existed and suggested that attitudinal gender differences related to physical science begin to develop by the earliest elementary school years. Policy implications are that intervention programs designed to promote gender equity should be extended to the early elementary school years and also should address parental attitudes. Additional implications for policy and research are discussed. © 1999 John Wiley & Sons, Inc. J Res Sci Teach 36: 719–747, 1999 相似文献
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66.
The aim of this research is to characterize the development of fatigue damage by means of stress-strain hysteresis. Experiments were conducted on 14 specimens made of cold-finished unannealed AISI 1018 steel. Results demonstrate that the mechanical hysteresis loop areas, when plotted as a function of the number of loading cycles, show significant variations and demonstrate the three principal stages concerning the progress of the fatigue failure--initial accommodation, accretion of damage and terminal failure. These three stages of fatigue are marked by the transitions at cycles N2 and N3. Experimental results show that although fatigue life Nf ranges from 2644 cycles to 108 992 cycles, the ratios of N2/Nf and N3/Nf tend to be stable: N2/Nf=I 0.7%, N3/Nf=91.3%. 相似文献
67.
Benedicta D’Souza Vivian D’Souza S. Sowmya G. Seema C. N. Hemalatha M. Anu G. Sajana 《Indian journal of clinical biochemistry : IJCB》2008,23(3):218-222
The study was conducted to find out the extent of lipid peroxidation and antioxidant status in ischemic stroke patients (ISPs)
with and without diabetes. Malondialdehyde (MDA) was studied as a marker of lipid peroxidation. Glutathione (GSH), uric acid
and ceruloplasmin were estimated to study the antioxidant potential of ISPs. Significantly higher levels of MDA were found
in both the groups of ISPs and the increase in MDA was more in ISPs without diabetes. GSH levels were decreased significantly
in both the groups of ISPs and maximum decline was found in ISPs with diabetes. Uric acid levels were significantly increased
in both the groups of ISPs. Ceruloplasmin levels were increased significantly in ISPs without diabetes, whereas its levels
were slightly decreased in ISPs with diabetes. A negative correlation was found between MDA and the antioxidants GSH, uric
acid and ceruloplasmin in ISPs with diabetes. This study suggests that there is an association between ischemic stroke and
increased oxidative stress and the antioxidant potential is impaired in both the groups of ISPs with and without diabetes. 相似文献
68.
Size-dependent trajectories of DNA macromolecules due to insulative dielectrophoresis in submicrometer-deep fluidic channels 总被引:1,自引:0,他引:1
Gea O. F. Parikesit Anton P. Markesteijn Oana M. Piciu Andre Bossche Jerry Westerweel Ian T. Young Yuval Garini 《Biomicrofluidics》2008,2(2)
In this paper, we demonstrate for the first time that insulative dielectrophoresis can induce size-dependent trajectories of DNA macromolecules. We experimentally use λ (48.5 kbp) and T4GT7 (165.6 kbp) DNA molecules flowing continuously around a sharp corner inside fluidic channels with a depth of 0.4 μm. Numerical simulation of the electrokinetic force distribution inside the channels is in qualitative agreement with our experimentally observed trajectories. We discuss a possible physical mechanism for the DNA polarization and dielectrophoresis inside confining channels, based on the observed dielectrophoresis responses due to different DNA sizes and various electric fields applied between the inlet and the outlet. The proposed physical mechanism indicates that further extensive investigations, both theoretically and experimentally, would be very useful to better elucidate the forces involved at DNA dielectrophoresis. When applied for size-based sorting of DNA molecules, our sorting method offers two major advantages compared to earlier attempts with insulative dielectrophoresis: Its continuous operation allows for high-throughput analysis, and it only requires electric field strengths as low as ∼10 V∕cm. 相似文献
69.
The objective of this study was to evaluate acrosin activity in spermatozoa of infertile Nigerian men and to compare with
those of the fertile men. The acrosin activity was evaluated using the Acroscreen reagent kit. The acrosin activity of the
fertile men was 40.7±5.2 mIU/106 sperm (range 30.1–51.3) and those of the infertile men was 22.4±8.33 mIU/106 sperm (range 5.7–39.1). The difference in the mean was statistically significant (P<0.001). There was a subpopulation of
the infertile men who had their acrosin activity within normal range of the fertile men, 32.9±1.57 mIU/106 sperm. But the difference in the mean was statistically significant (P<0.001). Acrosin activity decreased with increased
morphological changes in the spermatozoa. It is concluded that acrosin activity in the infertile Nigerian men is significantly
lower than that in the fertile men. Acrosin activity may also be affected by morphological changes in the spermatozoa. 相似文献
70.
The Inductive Query By Example (IQBE) paradigm allows a system to automatically derive queries for a specific Information Retrieval System (IRS). Classic IRSs based on this paradigm [Smith, M., & Smith, M. (1997). The use of genetic programming to build Boolean queries for text retrieval through relevance feedback. Journal of Information Science, 23(6), 423–431] generate a single solution (Boolean query) in each run, that with the best fitness value, which is usually based on a weighted combination of the basic performance criteria, precision and recall. 相似文献