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61.
Avinash Kumar Singh 《Prospects》1995,25(4):735-747
62.
What is the nature of the force or mechanism that moves massive continents thousands of miles across? What causes violent earthquakes to displace huge landmasses abruptly? How could great mountain ranges like Himalayas and Alps rise to such incredible heights? What makes earth's interior so restless? Answers to some of these questions may lie in understanding the Earth's interior itself. 相似文献
63.
This study investigated the effect of Pen-Point and Powerbook computers on solving a multiple step chemistry (molaritý) problem among White, Afro-American and Hispanic students (N=60) at the high school level. The screens on both computers were partitioned into a work field and a reasoning field. Both computers were programmed to record the time spent in each field, the number of entries made, and a copy of the entries made. Statistical analysis of data showed that more of the White and Afro-American Pen-Point computer users solved the problem correctly than did students using the Powerbook computer. All three ethnic groups made fewer entries, and took less time using the Pen-Point computer than the Powerbook. Attitude survey results of all ethnic groups showed that more Pen-Point computer users felt comfortable working with computers. Over all, the results suggest that the Pen-Point computer has a more positive effect on the problem solving performance and attitude of students towards computers than the Powerbook computer. 相似文献
64.
The ways computer technology could be used to teach science to students with learning disabilities (LD) are explored. Science is for all students and that includes students with LD. Learning science has both cognitive and affective implications for students with LD. In this context, computer technology provides cognitively engaging and motivating instructional tools for individualizing the mode of delivery; developing expert tutors; anchoring instruction; integrating science with other subjects; reducing cognitive load on working memory; and motivating students to stay on task. These applications are discussed with implications for teaching science to students with LD. 相似文献
65.
An interesting and relevant case involving two distinct systematic evaluations, traditional as well as somewhat nontraditional, of a science teacher education project with a heavy technology emphasis is discussed. Comparisons of the two separate evaluations of the same project revealed the complexity of evaluating technology projects and the multifaceted ways in which the evaluation endeavor could be approached, and provided an unusual situation and seldom seen opportunity for thinking about such evaluations. Additionally, what some other authors have said about the evaluations of efforts that take advantage of technology in the training of science teachers will also be explored. Evaluators must become active players in guiding the infusion of technology in preservice science programs. If evaluators, don't function to identify what works and what doesn't and what induces the best supportive environment, then who will? 相似文献
66.
The 2007 Nobel Prize in Physics was awarded to Albert Fert and Peter Grünberg for the discovery of giant magnetoresistance
(GMR). GMR is achieved in metallic multilayers, where the resistance of the multilayer changes considerably by the application
of a magnetic field. This has paved the way for high density data storage in magnetic media.
(left) Debakanata Samal is a research scholar at the Deaprtment of Physics at IISc, Bangalore. His research interests are
in magnetotransport in oxide multilayers, spintronics.
(right) P S Anil Kumar is an Asst. Professor at the Department of Physics, IISc Bangalore. His research interests are in spintronics,
magnetic nano-structures, surface-and thin-film magnetism, magnetotransport in metallic multilayers and oxides, and spin-polarized
electron scattering. 相似文献
67.
Lotka's law and institutional productivity 总被引:1,自引:0,他引:1
The present study aims at determining the applicability of Lotka's law, negative binomial distribution and lognormal distribution for institutional productivity, in the same way as it is to authors and their productivity in the field of engineering sciences and the patents filed by industrial firms in laser S&T. The study indicates that non of the three distributions are applicable for institutional productivity in engineering sciences. However, Lotka's law holds good for full as well as truncated set of data for the patents filed by industrial firms. 相似文献
68.
Satish Kumar 《Resonance》1999,4(4):45-55
In Part 1 of this article we understood the idea of a fuzzy set. We also reviewed simple operations such as fuzzy set intersection, union, and complementation, and related these to geometry. In Part 2, we extend the idea of fuzzy sets to explain how we may develop systems that reason with fuzzy sets using fuzzy logic. The idea of extending fuzzy logic to fuzzy engineering and fuzzy function approximation is explored with a working example. It is hoped that readers will be provided with enough motivation to appreciate the use of fuzzy set theory for real world applications. 相似文献
69.
Tiwari AK Mahdi AA Zahra F Chandyan S Srivastava VK Negi MP 《Indian journal of clinical biochemistry : IJCB》2010,25(4):411-418
The present study was conducted to investigate the oxidant–antioxidant status in iron deficient pregnant anemic women. One
hundred thirty pregnant women with iron deficiency anemia (IDA) were divided into three groups, namely mild (50), moderate
(50) and severe (30) anemic along with pregnant healthy women as controls (50). The complete blood count, plasma lipid peroxidation
products, enzymatic and non-enzymatic antioxidants were measured according to respective protocols. The levels of complete
blood count, iron, ferritin along with antioxidant enzymes namely catalase, superoxide dismutase, glutathione peroxidase,
glutathione reductase and reduced glutathione were significantly reduced in all IDA groups. However, the level of oxidized
glutathione, lipid peroxides, protein carbonyls, conjugated dienes were found significantly increased in all anemic patients.
Antioxidant vitamins, namely C, E and A were also found significantly decreased in IDA patients. On the basis of our results,
it may be concluded that IDA tends to increase the pro-oxidant components, which may result in various complications including
peroxidation of vital body molecules resulting in increased risk for pregnant women as well as fetus. 相似文献
70.
The correlation between antioxidant capacity and oxidative damage during aging has been reported in several tissues in different
species. Glutathione-S-transferases (GST) can metabolise endogenous and exogenous toxins and carcinogens by catalysing the
conjugation of diverse electrophiles with reduced glutathione (GSH). We observe a significant (P < 0.001) increase in plasma GST activity as a function of human age (r = 0.5675). A significant (P < 0.001) positive correlation (r = 0.8979) is observed between GST activity and total plasma antioxidant potential measured
as ferric reducing ability of the plasma (FRAP). GST activity and red cell intracellular GSH also show a significant positive
correlation (r = 0.7014). We hypothesize that the increased activity of plasma GST is a manifestation of increased generation
of ROS and a concomitant decrease in the level of plasma antioxidant capacity during aging. 相似文献