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1.
Aditi Chatterjee Jayabrata Biswas Kiranmoy Das 《International Journal of Communication Systems》2020,33(9)
In recent years, Internet of Things (IoT) devices are used for remote health monitoring. For remotely monitoring a patient, only the health information at different time points are not sufficient; predicted values of biomarkers (for some future time points) are also important. In this article, we propose a powerful statistical model for an efficient dynamic patient monitoring using wireless sensor nodes through Bayesian Learning (BL). We consider the setting where a set of correlated biomarkers are measured from a patient through wireless sensors, but the sensors only report the ordinal outcomes (say, good, fair, high, or very high) to the sink based on some prefixed thresholds. The challenge is to use the ordinal outcomes for monitoring and predicting the health status of the patient under consideration. We propose a linear mixed model where interbiomarker correlations and intrabiomarker dependence are modeled simultaneously. The estimated and the predicted values of the biomarkers are transferred over the internet so that health care providers and the family members of the patient can remotely monitor the patient. Extensive simulation studies are performed to assess practical usefulness of our proposed joint model, and the performance of the proposed joint model is compared to that of some other traditional models used in the literature. 相似文献
2.
Pavel Strunz Debashis Mukherji Přemysl Beran Ralph Gilles Lukas Karge Michael Hofmann Markus Hoelzel Joachim Rösler Gergely Farkas 《Metals and Materials International》2018,24(5):934-944
An addition of boron largely increases the ductility in polycrystalline high-temperature Co–Re alloys. Therefore, the effect of boron on the alloy structural characteristics is of high importance for the stability of the matrix at operational temperatures. Volume fractions of ε (hexagonal close-packed—hcp), γ (face-centered cubic—fcc) and σ (Cr2Re3 type) phases were measured at ambient and high temperatures (up to 1500 °C) for a boron-containing Co–17Re–23Cr alloy using neutron diffraction. The matrix phase undergoes an allotropic transformation from ε to γ structure at high temperatures, similar to pure cobalt and to the previously investigated, more complex Co–17Re–23Cr–1.2Ta–2.6C alloy. It was determined in this study that the transformation temperature depends on the boron content (0–1000 wt. ppm). Nevertheless, the transformation temperature did not change monotonically with the increase in the boron content but reached a minimum at approximately 200 ppm of boron. A probable reason is the interplay between the amount of boron in the matrix and the amount of σ phase, which binds hcp-stabilizing elements (Cr and Re). Moreover, borides were identified in alloys with high boron content. 相似文献
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Microsystem Technologies - This paper represents low power and high speed design issues of Hamming code generation and error detection circuit using complementary metal oxide semiconductor (CMOS)... 相似文献
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Summary Multicomponent intermacromolecular complexes have been prepared from some typical phenolic copolymers with a non-ionic polymer (e.g. PVP), and a polyelectrolyte (e.g. PAA). Some transition metal ions (e.g. Cu(II) and Ni (II)) have been incorporated in the complex through its unreacted co-ordinating groups. The formation of these complexes has been studied by several techniques, such as viscometry, conductometry, potentiometry, IR and UV spectrophotometry. A scheme has been presented to explain the mode of interaction of the various components. 相似文献
6.
Cardioprotective effects of a standardized extract from leaves with flowers of Crataegus (WS-1442; content of oligomeric procyandins [OPC]: 18.75%) have recently been demonstrated in an ischemia-reperfusion model in rats. Further studies were now conducted to clarify the mechanism of action and to identify active constituents involved in these effects of WS-1442. Exhausting partitioning between ethyl acetate/water and successive ultrafiltration of the aqueous layer led to the quantitative recovery of three fractions, which were tested for their in vitro radical scavenging (RS) and human neutrophil elastase (HNE) inhibitory activity. The lipophilic ethylacetate-soluble fraction A, enriched in flavone derivatives and constituting 14.9% of WS-1442, was as active as WS-1442 in inhibiting HNE. However, its RS activity was only about half that of the primary extract. Although 67.9% of WS-1442 was recovered in a water-soluble low molecular weight fraction B, this fraction displayed only weak RS and HNE inhibiting activity. In contrast, the RS and HNE inhibiting potencies of an essentially flavone-free and OPC-rich fraction C (21.3% of WS-1442) were significantly higher (inhibition of lipid peroxidation: IC50 0.3 microgram/ml; inhibition of HNE: IC50 0.84 microgram/ml) as those of WS-1442. The RS and HNE inhibitory activities of the extract and those of its fractions correlated well with their OPC-content but not with their concentration of flavonols. These results demonstrate that OPCs of Crataegus extracts possess stronger radical scavenging activities than flavone derivatives or other constituents. In addition, the oligomeric components are potent inhibitors of HNE. Oral administration of 20 mg/kg/d of the OPC-rich fraction C to rats afforded similar protection against ischemia-reperfusion induced pathologies as treatment with WS-1442 at a dose of 100 mg/kg/d. These observations indicate that radical scavenging and elastase inhibitory activities could indeed be involved in the observed cardioprotective effects of WS-1442, and demonstrate that OPCs are major orally active constituents of WS-1442. Thus, Crataegus extracts used therapeutically for cardiovascular diseases should be analyzed and standardized for their OPC-content. 相似文献
7.
T. Chatterjee K. Yurekli V.G. Hadjiev R. Krishnamoorti 《Advanced functional materials》2005,15(11):1832-1838
Dispersions of single‐walled carbon nanotubes (SWNTs) in poly(ethylene oxide) (PEO) assisted by a lithium‐based anionic surfactant demonstrate an electrical percolation of 0.03 wt.‐% and a geometrical percolation, inferred from melt rheometry, of 0.09 wt.‐%. Both the melting temperature and the extent of crystallinity of the PEO crystals decrease with increasing SWNT loading. Raman spectroscopy of the nanocomposites indicates a down‐shift of the SWNT G‐modes and suggests that the nanotubes are subjected to tensile stress transfer from the polymer at room temperature. 相似文献
8.
Friedel–Crafts acylation reaction between polystyrene and phthalic anhydride in the presence of AlCl3 has been performed in two different solvents, 1,2-dichloro ethane and nitro-benzene. The morphology of the condensate prepared in 1,2-dichloroethane has revealed the participation of 1,2-dichloroethane, i.e., a competitive Friedel–Crafts alkylation reaction. 相似文献
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The effectiveness of Cocos nucifera pollen extract immunotherapy (CPE-IT) was studied in 96 patients allergic to C. nucifera pollen. A placebo-controlled study was performed at random for a period of 6-12 months. The clinical status of the patients measured by the symptom-medication scores demonstrated that C. nucifera pollen-allergic patients had significant (p < 0.005) clinical improvement after CPE-IT in comparison to placebo treatment. Serological study resulted a significant reduction (p < 0.001) of specific IgE and significant elevation (p < 0.01) of specific IgG in post-therapeutic patients' sera which were correlated significantly (r = 0.45, p < 0.001); the changes of the above immunoglobulin levels in the placebo-treated patients were nonsignificant. However, there was no correlation between symptom-medication scores and changes in specific serum IgE or IgG levels. 相似文献