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1.
Pradeep Kumar 《Resonance》2017,22(4):399-405
Richard Feynman once said: “nobody understands quantum mechanics”. Still, those who devised it are perhaps the ones closest to understanding their creation. It suggests that whenever the weirdness of quantum mechanics haunts you, it is better to go back to its creators in terms of their original publications. In the present article, the author has tried to seek help from Heisenberg’s 1925 paper, in order to reduce the weirdness of going from classical observables to quantum operators.  相似文献   
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Journal of Science Education and Technology - The primary aim of the study was to examine whether performance on a science assessment in an immersive virtual environment was associated with changes...  相似文献   
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Methionine synthase reductase (MTRR) is an important enzyme of the folate/homocysteine pathway. It is responsible for regulation of methionine enzyme by reductive methylation. A common variant A66G is reported in the FMN-binding domain of the MTRR gene, which leads to substitution of isoleucine by methionine (I22M) in MTRR enzyme with reduced activity. Reduced catalytic activity of enzyme leads to high homocysteine concentration in blood and increases risk for numerous diseases. The frequency of A66G polymorphism varies in different ethnic groups. The present study has been designed to evaluate the frequency of MTRR A66G gene polymorphism in the Eastern UP population by PCR–RFLP method. Along with this we also performed a meta-analysis to evaluate the global prevalence of this polymorphism. Databases were screened to identified the eligible studies. The prevalence of the G allele and GG genotype was determined by the use of prevalence proportion with 95% CI. Open meta-analyst software was used for the meta-analysis. Total 1000 blood samples were analyzed, the frequencies of A and G alleles were 0.35 and 0.65 respectively. Meta-analysis results revealed that the prevalence of G allele and GG genotype were 49.4% (95% CI 40.6–58.1, p ≤ 0.001) and 24.3% (95% CI 17.8–30.9, p ≤ 0.001) respectively. In sub-group meta-analysis, the lowest frequency of G allele was found in South America (32.7%; 95% CI 14.1–51.3, p ≤ 0.001), and highest in Asia (56.4%; 95% CI 39.5–73.3, p ≤ 0.001). The results of the meta-analysis showed that the Asian population has the highest frequency of G allele and highest frequency of the GG genotype was found in the European population.  相似文献   
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In this study, we compared hamstring (H) and quadriceps (Q) strength changes in men and women, as well as changes in conventional and functional H:Q ratios following an identical 12-week resistance training program. An isokinetic dynamometer was used to assess 14 male and 14 female participants before and after the intervention, and conventional and functional H:Q ratios were calculated. Hamstring strength improved similarly in men and women, but improvement in quadriceps strength was significantly greater in men, while women showed only modest improvements. For the conventional and functional H:Q ratios, women showed significantly greater improvements than men. Both men and women were able to exceed the commonly recommended 0.6 conventional and 1.0 functional H:Q ratios after the 12-week lower-body resistance training program.  相似文献   
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Space and time are concepts that seem to be embedded in our very consciousness. As we grow up, our ‘intuitive understanding’ of these concepts seems to grow as well. And yet the fact is that our understanding of space-time in the deepest scientific sense is far from complete, although we have covered a considerable distance along the route. There may still be many surprises awaiting us on the road ahead.  相似文献   
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This paper describes Dragoon, a simple intelligent tutoring system which teaches the construction of models of dynamic systems. Modelling is one of seven practices dictated in two new sets of educational standards in the U.S.A., and Dragoon is one of the first systems for teaching model construction for dynamic systems. Dragoon can be classified as a step-based tutoring system that uses example-tracing, an explicit pedagogical policy and an open learner model. Dragoon can also be used for computer-supported collaborative learning, and provides tools for classroom orchestration. This paper describes the features, user interfaces, and architecture of Dragoon; compares and contrasts Dragoon with other intelligent tutoring systems; and presents a brief overview of formative and summative evaluations of Dragoon in both high school and college classes. Of four summative evaluations, three found that students who used Dragoon learned more about the target system than students who did equivalent work without Dragoon.  相似文献   
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Theoretical analysis of the ‘simple’ pendulum beyond the small-angle approximation teaches us about anharmonic oscillators and approximate (perturbative) solutions. Experiments with a simple-to-set-up pendulum teach us about errors in measurements, and curve fitting of theoretical expressions to experimental data. The pendulum also exhibits frictional damping, a feature of most real oscillators.  相似文献   
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