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51.
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Solitons emerge as non-perturbative solutions of non-linear wave equations in classical and quantum theories. These are non-dispersive
and localised packets of energy — remarkable properties for solutions of non-linear differential equations. In the presence
of such objects, the solutions of Dirac equation lead to the curious phenomenon of ‘fractional fermion number’. Under normal
conditions the fermion number takes strictly integral values. In this article, we describe this accidental discovery and its
manifestation in polyacetylene chains, which has led to the development of organic conductors.
(left) Kumar Rao is a Postdoctoral Fellow at PRL, Ahmedabad. He is interested in particle physics phenomenology as probed
in particle colliders and formal aspects of quantum field theory.
(right) Narendra Sahu is currently a postdoctoral fellow at Lancaster University, UK. His main research area includes Cosmology
and Astroparticle physics. Currently he is working on dark matter and matter anti-matter asymmetry of the universe.
(center) P K Panigrahi’s research interests are in the area of quantum computation, solitons in Bose Einstein condensates
& nonlinear optical media. He is also deeply interested in science education and derives pleasure from long weekend walks. 相似文献
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Shubham Goel Ravinder Kumar Munish Kumar Vikram Chopra 《Information processing & management》2019,56(3):1053-1066
In the whole world, the internet is exercised by millions of people every day for information retrieval. Even for a small to smaller task like fixing a fan, to cook food or even to iron clothes persons opt to search the web. To fulfill the information needs of people, there are billions of web pages, each having a different degree of relevance to the topic of interest (TOI), scattered throughout the web but this huge size makes manual information retrieval impossible. The page ranking algorithm is an integral part of search engines as it arranges web pages associated with a queried TOI in order of their relevance level. It, therefore, plays an important role in regulating the search quality and user experience for information retrieval. PageRank, HITS, and SALSA are well-known page ranking algorithm based on link structure analysis of a seed set, but ranking given by them has not yet been efficient. In this paper, we propose a variant of SALSA to give sNorm(p) for the efficient ranking of web pages. Our approach relies on a p-Norm from Vector Norm family in a novel way for the ranking of web pages as Vector Norms can reduce the impact of low authority weight in hub weight calculation in an efficient way. Our study, then compares the rankings given by PageRank, HITS, SALSA, and sNorm(p) to the same pages in the same query. The effectiveness of the proposed approach over state of the art methods has been shown using performance measurement technique, Mean Reciprocal Rank (MRR), Precision, Mean Average Precision (MAP), Discounted Cumulative Gain (DCG) and Normalized DCG (NDCG). The experimentation is performed on a dataset acquired after pre-processing of the results collected from initial few pages retrieved for a query by the Google search engine. Based on the type and amount of in-hand domain expertise 30 queries are designed. The extensive evaluation and result analysis are performed using MRR, [email protected], MAP, DCG, and NDCG as the performance measuring statistical metrics. Furthermore, results are statistically verified using a significance test. Findings show that our approach outperforms state of the art methods by attaining 0.8666 as MRR value, 0.7957 as MAP value. Thus contributing to the improvement in the ranking of web pages more efficiently as compared to its counterparts. 相似文献
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Sonika Gupta Niraj Shende Swati Banerjee Satish Kumar M. V. R. Reddy Bhaskar C. Harinath 《Indian journal of clinical biochemistry : IJCB》2002,17(1):5-8
Tuberculosis remains major health problem in India and developing countries Immunodiagnosis has important role in screening,
diagnosis and management of tuberculosis. SEVA TB ES-31 antigen has shown potential in detecting tuberculous IgG antibody
in earlier studies from our laboratory. In the present study we have analysedSEVA TB ES-31 antigen specific immunoglobulinsIgM, IgA and IgG in clinically and bacteriologically confirmed pulmonary tuberculosis cases to determine the usefulness of specific immunoglobulin
class in the diagnosis of patients attending the hospital.
Of the 30 cases of pulmonary tuberculosis 25 (83.3%) were positive for IgG, 19 (63.3%) for IgM and 16 (53.3%) for IgA. On
combining IgG and IgM positivity, sensitivity was increased to 93.3%. While combining IgG and IgA positivity, sensitivity
increased to 90%. However specificity was decreased to 66.6% and 70% for both of these combinations respectively. It could
be envisaged from this study that IgG antibody detection against ES-31 antigen showed acceptable sensitivity (83.3%) and specificity
(86.6%) compared to IgM or IgA alone or in combination. When immune responses were analysed according to degree of sputum
positivity, IgG response was observed to be predominant in all grades, compared to IgM or IgA antibody. The addition of IgM
or IgA as an adjunct test increases the sensitivity but at the cost of specificity. Hence the detection of IgG alone is more
useful compared to IgM or IgA assay, in detecting tuberculosis disease cases coming to the hospital. 相似文献
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Yeldose Sonu S. S. Avinash Sreekantha K. Arun Kumar M. Malathi A. R. Shivashankara 《Indian journal of clinical biochemistry : IJCB》2016,31(3):326-331
Given the paucity of studies conducted to know the effect of suddenness and earlier onset of endocrinological changes associated with hysterectomy, on the serum and urinary levels of calcium, magnesium and phosphate the present study was conducted to compare the levels of calcium, magnesium and phosphate in serum and urine of hysterectomised and natural menopausal south Indian women. This is a cross-sectional observational study. The study included three groups of 30 healthy premenopausal, 30 early surgical menopausal and 30 natural post menopausal women. Women suffering from any endocrine disease were excluded. Analysis was performed in serum and urine sample. The levels of calcium, magnesium and phosphate in serum and calcium/creatinine, magnesium/creatinine and phosphate/creatinine ratio were estimated in urine by spectrophotometric method. Hysterectomised women (serum calcium: 8.7 ± 0.09 mg/dl; urine calcium/creatinine: 0.16 ± 0.02) have significantly low serum calcium (p < 0.001) and high urinary calcium/creatinine (p = 0.002) ratio and post menopausal women (serum magnesium: 2.1 ± 0.03; serum phosphate: 4.4 ± 0.16; urinary calcium/creatinine: 0.17 ± 0.02; urinary magnesium/creatinine: 0.09 ± 0.01) have significantly high serum magnesium (p = 0.016), serum phosphate (p = 0.043) and high urinary calcium/creatinine (p = 0.002), magnesium/creatinine ratio (p = 0.025) compared to healthy pre menopausal women. Post menopausal women (serum calcium: 9.1 ± 0.08) have significantly high serum calcium and phosphate compared to hysterectomised women (serum phosphate: 3.93 ± 0.11). Hysterectomised women have significantly low serum calcium, oestrogen and high urinary calcium/creatinine ratio compared to healthy premenopausal women and low serum calcium and low serum phosphate compared to natural postmenopausal women. Natural postmenopausal women had low serum oestrogen and high serum magnesium, serum phosphate, urinary calcium creatinine ratio and urinary magnesium creatinine ratio compared to healthy premenopausal women. 相似文献
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Fang-Ying Yang Kaushal Kumar Bhagat Chia-Hui Cheng 《International Journal of Science Education》2019,41(10):1347-1365
The purpose of this study was to compare the associations of epistemic beliefs in science, performance of scientific reasoning in university students from Taiwan and India, and the relations with their science learning experiences. A total of 126 university students including 67 from Taiwan and 59 from India who had science and mathematics backgrounds were involved in the study. Students’ epistemic beliefs in science were assessed by the SEV questionnaire, while their reasoning performance and learning experiences were prompted by open-ended questions and survey items. Content analysis was performed to analyze their scientific reasoning, and correlation analysis, t tests and ANOVA were applied to reveal the associations between variables. The results showed that students from both countries differed in epistemic beliefs in the dimensions of certainty, development and justification. While few students from either country performed successfully in identifying genuine evidence and giving full rebuttals, Taiwanese participants seemed to demonstrate slightly better scientific reasoning. It was found that the Indian students were more balanced in receiving structured and engaged learning experiences. Varying associations for the students from the different countries were found between epistemic beliefs and scientific reasoning performance, and between epistemic beliefs and science learning experiences. 相似文献