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Gaurav Bajpai Tulika Srivastava N. Patra Igamcha Moirangthem S. N. Jha D. Bhattacharyya Sk Riyajuddin Kaushik Ghosh Dharma R. Basaula Mahmud Khan Shun-Wei Liu Sajal Biring Somaditya Sen 《RSC advances》2018,8(43):24355
Substituting an ion of different size from that of the host element introduces lattice strain and defects. However, this mismatch may be significantly reduced by substituting an additional ion with a compensating size relative to the dopant. Such a double substitution might offer better solubility irrespective of the local distortions as well as the formation of defects in the valence states. Fe-substituted ZnO has been widely reported with conflicting results primarily arising from lack of chemical and structural homogeneity originating from preparation techniques, compositional fluctuations, and equivocal comprehension of actual solubility limits of the dopants. In this study, Ag ion has been incorporated in Fe-substituted ZnO to compensate the ionic size of Zn1−x[Fe0.8Ag0.2]xO (0 ≤ x ≤ 0.03125) by determining the solubility limit of the homogeneous material and their corresponding structural, mechanical, optical and magnetic properties have been investigated thoroughly. Co-substitution rearranges the lattice and leads to better crystal structures with tunable properties related to the amount of substitution.Substituting an ion of different size from that of the host element introduces lattice strain and defects. 相似文献
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Background
Tanzania is the country hit the hardest by the HIV epidemic in Sub-Saharan Africa. The present study was carried out to examine the factors of HIV infection among women who lived in an urban area in Tanzania.Methods
The Tanzania HIV/AIDS and Malaria Indicator Survey (2011–12) data was used. The sample size for urban and rural women who had been tested for HIV and ever had sex was 2227 and 6210 respectively. Bivariate and multivariate logistic regression analyses were used.Results
The present study found that rural women were significantly less likely to be HIV-infected compared to urban women (OR = 0.612, p<0.00). About 10% urban women were HIV-infected whereas 5.8% women in rural areas were HIV positive. Women who had more than five sex partners were significantly four times more likely to be HIV-infected as compared to women who had one sex partner (OR = 4.49, p<0.00).Conclusion
The results of this study suggest that less-educated women, women belonging to poor or poorer quintile, women spending nights outside and women having more than one sex partner were significantly more likely to have HIV infection among urban women as compared to rural women. There is an urgent need for a short and effective program to control the HIV epidemic in urban areas of Tanzania especially for less-educated urban women. 相似文献66.
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Indirect evidence has suggested the existence of a second chitinase gene, PgCHT2, in the avian malaria parasite Plasmodium gallinaceum. We have now identified PgCHT2 as the orthologue of the P. falciparum chitinase gene PfCHT1, a malaria transmission-blocking target. Computational phylogenetic evidence and biochemical and cell biological functional data support the hypothesis that an avian-related Plasmodium species was the ancestor of both P. falciparum and P. reichenowi, and this single lineage gave rise to another lineage of malaria parasites, including P. vivax, P. knowlesi, P. berghei, P. yoelii, and P. chabaudi. A recombinant PfCHT1/PgCHT2-neutralizing single-chain antibody significantly reduced P. falciparum and P. gallinaceum parasite transmission to mosquitoes. This single-chain antibody is the first anti-P. falciparum effector molecule to be validated for making a malaria transmission-refractory transgenic Anopheles species mosquito. P. gallinaceum is a relevant animal model that facilitates a mechanistic understanding of P. falciparum invasion of the mosquito midgut. 相似文献
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Involvement of guanine nucleotide binding proteins in neutrophil activation and priming by GM-CSF 总被引:4,自引:0,他引:4
Pre-incubation of human neutrophils with pertussis toxin significantly inhibited the neutrophil-directed biologic actions of granulocyte- macrophage colony-stimulating factor (GM-CSF) in three separate assays: the induction of c-fos mRNA, the enhancement of both platelet- activating factor-induced mobilization of intracellular calcium, and stimulation of leukotriene synthesis by the calcium ionophore A23187. Cholera toxin did not have an effect on the latter two assays. Pre- treatment of human neutrophils with pertussis toxin did not affect the binding of GM-CSF to its surface receptor. These results provide the first evidence that a pertussis toxin substrate plays an important mediatory role in the mechanism of action of GM-CSF. 相似文献
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Time‐Dependent Changes in QT Dynamics after Initiation and Termination of Paroxysmal Atrial Fibrillation
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