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The dominant understanding of Internet censorship posits that blocking access to foreign-based websites creates isolated communities of Internet users. We question this discourse for its assumption that if given access people would use all websites. We develop a conceptual framework that integrates access blockage with social structures to explain Web users’ choices, and argue that users visit websites they find culturally proximate and that access blockage matters only when such sites are blocked. We examine the case of China, where online blockage is notoriously comprehensive, and compare Chinese Web usage patterns with those elsewhere. Analyzing audience traffic among the 1000 most visited websites, we find that websites cluster according to language and geography. Chinese websites constitute one cluster, which resembles other such geolinguistic clusters in terms of both its composition and its degree of isolation. Our sociological investigation reveals a greater role of cultural proximity than access blockage in explaining online behaviors. 相似文献
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P-selectin, a cell adhesion molecule is elevated in many inflammatory conditions including preeclampsia which is characterized
by generalized endothelial dysfunction and vasoconstriction presumably due to free radicals or mediators released by defective
placentation. Vitamin E has been documented to protect cell membranes from oxidative damage and also decrease platelet aggregation.
The role of vitamin E in pre-eclampsia is contradictory and hence the study was undertaken. Soluble P-selectin was measured
by ELISA and Vitamin-E levels in plasma was estimated spectrofluorometrically. In our study the effect of supplementation
of 400 IU/day of Vitamin E (a-tocopheryl acetate) to patients of pre-eclampsia showed significant decreased levels of soluble
P-selectin by 2nd week as compared to patients given placebo (P = 0.005). In this short period of study no direct correlations were observed between Vitamin E or P-selectin levels with
blood pressure as well as with proteinuria. Future studies may focus on the effect of a-tocopheryl acetate or the phosphate
form of Vitamin-E, recently proposed to be the more active form on other inflammatory markers like IL-6, an important stimuli
of P-selectin release in pre-eclampsia. 相似文献
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Wang JP Raman H Zhang GP Mendham N Zhou MX 《Journal of Zhejiang University. Science. B》2006,7(10):769-787
Aluminium （Al） toxicity is one of the major limiting factors for barley production on acid soils. It inhibits root cell division and elongation, thus reducing water and nutrient uptake, consequently resulting in poor plant growth and yield. Plants tolerate Al either through external resistance mechanisms, by which Al is excluded from plant tissues or internal tolerance mechanisms, conferring the ability of plants to tolerate Al ion in the plant symplasm where Al that has permeated the plas- malemma is sequestered or converted into an innocuous form. Barley is considered to be most sensitive to Al toxicity among cereal species. Al tolerance in barley has been assessed by several methods, such as nutrient solution culture, soil bioassay and field screening. Genetic and molecular mapping research has shown that Al tolerance in barley is controlled by a single locus which is located on chromosome 4H. Molecular markers linked with Al tolerance loci have been identified and validated in a range of diverse populations. This paper reviews the （1） screening methods for evaluating Al tolerance, （2） genetics and （3） mechanisms underlying Al tolerance in barley. 相似文献
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Science, Technology & Society (STS) graduate programs primarily train graduate students to work in tenure track academic jobs. However, there are not enough tenure track academic jobs to match the supply of STS graduate students, nor does every STS graduate student want to become an academic. As a start to addressing these challenges, we hosted workshops before the 2017 Society for the Annual Meeting of the Society Studies of Science and the 2018 ST Global conference. In those workshops, panelists with PhDs in STS and related fields and working in non-academic faculty careers such as government agencies, non-profit foundations, and industry emphasized that students must showcase how their skills are useful to non-academic organizations. The panelists offered a wealth of stories on how their STS perspective supported their careers, yet most had faced implicit and explicit mentoring from STS faculty that ran counter to their career aspirations. The conversations centered on reframing research and conveying to potential employers how their STS training would support their future careers. A takeaway point that resonated with many participants was the need for STS graduate programs to rethink how they market themselves, recruit students, and critically reflect upon the measures of success. By implicitly steering graduate students solely towards an academic career, STS graduate training will miss an opportunity to make a positive impact on society. 相似文献
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The dropout rate among Spanish university students is very high compared to the European mean, creating a pressing need for the introduction of policies and programmes aimed at increasing rates of persistence. In this article, we study this problem by combining students’ perceived learning outcomes with their dropout intentions, and we propose a research model that considers subjective factors that might impact this decision. The model is estimated for two degree courses: Business Administration and Nursing. The estimation method uses structural equations based on the partial least squares algorithm. This allows the construction of indices for the variables of interest, enabling us to make comparisons between courses and over time. To reduce dropout intentions, efforts need to be focused on obtaining better cognitive outcomes, as well as on achieving a higher level of student satisfaction with their university experience. 相似文献
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Pradeep Sharma Neelima Singh Vinod Singh Sanjeev Singh Harsh vardhan Singh Sameer Gupta 《Indian journal of clinical biochemistry : IJCB》2006,21(1):205-207
Osteoarthritis of knee joints is a disease of old age in both sex. It is very common after the age of 40 years in elderly
females or in postmenopausal phase of females. It is characterized by narrowing of space in joints due to inflammation. The
exact mechanism of inflammation in this disease is not yet clear. Tumor necrosis factor alpha (TNF-α) may involve in onset
of disease. The present study is being carried out in 130 female subject of age group 40–60 years suffering from osteoarthritis
of knee joints and 50 normal healthy control female subjects. A correlation is made between TNF-α and estrogen and found significant
inverse correlation (r<0.001), between TNF-α and estrogen hormone in osteoarthritic female patients as compared to normal
healthy control female group. 相似文献