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Bhattacharya Subhayan Sinha Sankhamita Roy Sarbani Gupta Amarnath 《The Journal of supercomputing》2020,76(12):9882-9900
The Journal of Supercomputing - Currently, all online social networks (OSNs) are considered to follow a power-law distribution. In this paper, the degree distribution for multiple OSNs has been... 相似文献
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V. Sinha M. J. Mills J. C. Williams 《Metallurgical and Materials Transactions A》2006,37(6):2015-2026
A faceted initiation site is observed in Ti-6242 alloy for both the cyclic and static-loading test conditions. In this experimental
study, the crystallographic orientation of the facets has been determined using the electron backscattered diffraction (EBSD)
technique in conjunction with the quantitative tilt fractography in a scanning electron microscope (SEM). Quantitative tilt
fractography analysis has been used to determine the spatial orientation of fracture facets. The results indicate that the
normal-fatigue (no-dwell) fracture facets are oriented at ∼5 deg with respect to the basal plane; the dwell-fatigue fracture
facets are oriented at ∼10 to 15 deg with respect to the basal plane and the static-loading fracture facets are oriented at
∼20 deg with respect to the basal plane. These crystallographic orientation determinations of the fracture facets at the crack-initiation
site can be used to obtain an idea about the type of loading that produced them. 相似文献
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Family nursing, always a component of nursing, has been recently receiving increased attention through publications, educational programs, clinical practice settings and family nursing research. Nurses are in the best position to assist families experiencing the illness of a loved one, but often lack the skills and confidence necessary to assist with the psychosocial needs. The purpose of this paper is to describe the development and implementation of a family nursing program within a large, tertiary care facility. The program's evaluation is ongoing but early outcomes indicate that day-to-day nursing practice has been positively influenced and improved job satisfaction may result. 相似文献
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Effect of thapsigargin on calcium homeostasis in Trypanosoma cruzi trypomastigotes and epimastigotes
By using the fluorescent calcium indicator fura-2, it was found that the concentration of free Ca2+ in the cytoplasm of Trypanosoma cruzi trypomastigotes incubated in the presence or absence of external calcium was maintained at very low levels (10-20 nM). When trypomastigotes were incubated in the presence of succinate and ATP and permeabilized with digitonin, they lowered the medium calcium concentration to a submicromolar level. In the presence of 1 microM FCCP the initial rate of Ca2+ sequestration by these permeabilized cells was very slow. When succinate alone was present, the initial rate of Ca2+ accumulation was slower than with ATP plus succinate, and the calcium set point was about 0.6 microM. The succinate dependence and FCCP sensitivity of the later Ca2+ uptake indicate that it may be exerted by the mitochondria. High concentrations of the tumor promoter thapsigargin slightly increased cytosolic Ca2+ in the presence of extracellular Ca2+ but had no effect on the FCCP- and oligomycin/antimycin A-insensitive Ca2+ pool. In addition, when used at those concentrations (4-20 microM), thapsigargin was shown to release Ca2+ from the mitochondria and to decrease the inner mitochondrial membrane potential of trypomastigotes and epimastigotes as measured using safranine O. Despite the presence of inositol phosphates as determined by [3H]inositol incorporation, no IP3-sensitive Ca2+ release could be detected in trypomastigotes. 相似文献
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