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71.
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   
72.
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   
73.
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   
74.
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   
75.
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   
76.
Every individual should be entrusted with an internal driver to strive their best towards achieving their potential and to manifest their performance through innovative means. This can be reached only under circumstances where the abstract human values and principles are recognized and indoctrinated in the culture. The strategies discussed in this article will serve as input in proposing the areas of focus toward the practice of human governance.  相似文献   
77.
78.
Ujjal Kumar Sur 《Resonance》2010,15(2):154-164
In Raman spectroscopy, inelastic scattering of photons from an atomor molecule in chemical entities is utilized to analyze the composition of solids, liquids and gases. However, the low cross-section limits its applications. The introduction of surface-enhancedRamanspectroscopy in 1974has attracteda lot of attention fromresearchers due to the large enhancement of weak Raman signal,which facilitates identification in chemical and biological systems. Recently, single-molecule Raman scattering has enhanced the detection sensitivity limit of Raman Spectroscopy.  相似文献   
79.
The world of mobile communications is poised for yet another disruptive transformation – the introduction of 5G. It will change the way mobile phones communicate. New technologies at the device level and novel network architectures to manage them will be soon seen everywhere. This article explores what 5G is all about. It also talks briefly about the preparations underway across the globe to deploy 5G by 2020.  相似文献   
80.
In this article, we report some experimental results on the behaviour of the flame of a candle kept at the bottom of a glass tube, which is open at the top and closed at the bottom. Thus, the supply of oxygen for the continuous burning of the flame is possible only from the top open end of the tube. We find that the candle burns steadily below a critical tube height. Above this height, the flame oscillates in size, and a further increase in tube height leads to the flame extinguishing quickly.  相似文献   
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