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61.
This two-part article considers certain fundamental symmetries of nature, namely the discrete symmetries of parity (P), charge conjugation (C) and time reversal (T), and their possible violation. Recent experimental results are discussed in some depth. In this second part, we discussCP andT violation and arrive at a synthesis. 相似文献
62.
63.
Sarah Sharma 《传播与批判/文化研究》2014,11(1):5-14
While much of Occupy's political power is rooted in its spatial tactic, the movement's temporal realities are also key to understanding its complexities. This talk considers those realities, specifically turning to the night: a time when the spatial practice of occupying and the temporality of precarity find each other in a strange embrace. In the dark, new and unheard of demands emerge for the first time. At night, the fault lines of the movement rupture to the surface in new ways. It is also at night that those outside the camps, from the police, journalists, and the public, fix their gaze upon Occupy. Night also reflects the lived experience of precarity that Occupy and other activists and theorists have long mobilized against. This paper considers what new strategies of resistance loom in the realm of time. 相似文献
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65.
Living organisms ranging from bacteria to human beings exhibit 24-h rhythms in various behaviours and physiological processes. Matching of the period of such rhythms with that of the daily environmental cycles gives an impression that they are mere passive responses to environmental changes. Here, we discuss the change in our perception about daily biological rhythms, from their identity as rhythmic phenomena occurring as passive response to environmental changes, to the biological clocks. This is the first article in a series of articles on circadian rhythms which will cover discussion on the genetic and molecular basis, circadian organization and its adaptive significance. 相似文献
66.
Ramesh C. Sharma 《Open Learning》2013,28(3):227-241
Distance education has a history of over four decades in India. There has been a vast growth in the number of learners who need education and thus also the corresponding channels of providing education. Due to the constraints of the traditional educational sector, open and distance learning has been found to be a workable alternative strategy in India. This paper traces the evolution and diversification of open learning in India by examining various factors that led to the growth and success of open learning. This system, as other systems of education, is not free from problems and a critique is provided on the various factors affecting the smooth functioning of India’s open and distance learning system. 相似文献
67.
Kyoungna Kim Priya Sharma Susan M. Land Kevin P. Furlong 《Innovative Higher Education》2013,38(3):223-235
To enhance students’ critical thinking in an undergraduate general science course, we designed and implemented active learning modules by incorporating group-based learning with authentic tasks, scaffolding, and individual reports. This study examined the levels of critical thinking students exhibited in individual reports and the students’ critical thinking level change over time. Findings indicated that students’ average critical thinking level fell in the category of “developing”, but students’ scores on individual reports revealed a statistically significant increase. The study suggested that the active learning strategies employed in the study were useful to promote student critical thinking. 相似文献
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D. C. Sharma Gora Dadheech Bushra Fiza Meghna Mathur Manminder Riyat Praveen Sharma 《Indian journal of clinical biochemistry : IJCB》2009,24(2):202-204
Silver is ingested in India in the form of varak, Ayurvedic bhasm and water contained in silver utensils, but nobody knows
their effects. We have examined the effect of interaction of silver ingested in the form of varak (leaf), bhasm (ash) and
water (colloidal solution) on some essential elements (Na, K, Ca, Mg, Cu, Fe and Zn) in blood, liver, spleen and kidneys of
chicks. The results showed significant rise of silver in all the tissues and significant fall in copper in the blood. The
greatest rise was obtained in blood silver by silver sol while it had the lowest amount of silver. Iron significantly increased
in tissues but somewhat decreased in blood. Zinc content increased in all the tissues by leaf and ash but decreased by sol.
No consistent pattern was seen in case of other elements. 相似文献
70.
Sunil Chandy M. N. Sadananda Adiga Girija Ramaswamy C. Ramachandra Lakshmi Krishnamoorthy 《Indian journal of clinical biochemistry : IJCB》2008,23(3):258-261
Folate and cobalamin (Vitamin B12) are two essential micronutrients involved in one-carbon metabolism, which affects heart disease, neural tube defects and
cancer. Methylenetetrahydrofolate reductase, the key enzyme involved in one carbon metabolism produces methyl tetrahydrofolate
from methylene tetrahydrofolate, which in turn donates methyl group to homocysteine to generate methionine. There exist two
common low function polymorphic variants of the methylenetetrahydrofolate reductase gene involving nucleotides 677 C→T and
1298 A→C, which are associated with hyperhomocysteinemia. These polymorphisms are also linked with increased risk for certain
cancers such as breast cancer and at the same time providing a protective effect on colorectal cancer. In this case control
study, we have evaluated levels of folic acid, vitamin B12 and homocysteine in patients with colorectal cancer. Folate and homocysteine levels did not differ significantly between
the two groups; however an increasing trend was noticed with increase in homocysteine levels. Vitamin B12 levels were increased in cases compared to control group. 相似文献