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61.
The performance of two median-based methods, namely, median method (MM) and least median of squares (LMS), for parameter estimation in Arrhenius equation is investigated and compared with least sum of squares, through extensive Monte Carlo tests involving simulated data. Reweighted methods associated with LMS are also included in the study. Different types of experimental noise are considered for simulating variable standard deviation (SD) of noise and the occurrence of outliers. The results indicate the relative precision and accuracy of various methods for each noise type, and hence are useful in selecting the most appropriate method for a specific application provided noise type is known. Often little or no information is available on variation of SD and occurrence of outliers, and in such situations the most appropriate method seems to be MM which is observed to be the best for many noise types.  相似文献   
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The charge-carrier mobility of organic semiconductors extracted from thin-film transistors is highly dependent on film morphology. Morphological defects can lead to the underestimation of charge transport properties, which may impede the rational design of novel materials. Herein, a novel analytical method is presented to functionally characterize entire active layers of solution-processed thin-film transistors. By correlating imaging and spectroscopy of secondary electrons, nano-sized morphological defects are discovered and the effective current paths between source and drain electrodes are directly visualized. After image-processing, the as-measured mobility values of zone-cast thin-films of a tetraazaperopyrene derivative are corrected, obtaining charge–carrier mobilities of up to five times higher than the as-measured values. The direct visualization of the electric functionality of the organic thin-films facilitates a unique quantification of the impact of morphological defects and provides a solid benchmark to estimate the potential for further improvement of device performance.  相似文献   
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A large population is suffering from multifactorial urolithiasis worldwide with a reoccurrence rate of almost 70%–80% in males and 47%–60% in females. In the present study, the nephroprotective effect of silver nanoparticles (AgNPs) synthesised by Bryophyllum pinnatum was evaluated in ethylene glycol‐induced urolithiasis in rat. B. pinnatum‐mediated AgNPs which were found to be spherical and polydispersed particles with an average size of 32.65 nm determined by transmission electron microscopy analysis, and showing an absorption peak at 432 nm by the UV‐Vis spectrophotometric analysis, revealing the role of hydroxyl group in the synthesis by Fourier Transformed Infrared Spectroscopy analysis, with a zeta potential value of −15.7 mV. The crystalline nature and fcc structure was demonstrated based on X‐ray diffraction analysis. Animal study was performed on 36 male Wistar rats divided into six equal groups, which demonstrated significant increase in serum total protein, albumin and globulin and significant decrease in AST, ALT, creatinine, BUN, calcium and phosphorus in group V and VI when compared with group II and IV. No crystalluria was observed in rats given B. pinnatum AgNPs. Histopathological observations in group V and VI showed mild degenerative changes and restoration or maintenance of kidney parenchyma when compared with group II and IV rats. Thus, the authors conclude with the beneficial preventive and therapeutic nephroprotective effect of B. pinnatum‐mediated AgNPs against ethylene glycol‐induced urolithiasis in rats.  相似文献   
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Use of biologically modified gold nanoparticles (GNPs) as molecular vehicle to ferry potential anti-cancer drug berberine hydrochloride (BHC) using folic acid (FA) as targeting molecule is reported in this work. A tropical fruit peel, Trapa bispinosa is used to fabricate highly monodispersed GNPs, passivated with essential functional groups which were used as linkers to attach FA and BHC via amide linkage. Flocculation Parameter (FP) of biologically synthesized GNPs was calculated under different salt concentrations which were found to be very ideal under a physiological condition. Various statistical models were used to find drug release profile out of which Higuchi was found to be the most ideal. GNP–FA–BHC complexes were found to be active against folic acid expressing HeLa cells.  相似文献   
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Viburnum mullaha (Buch.-Ham. Ex D. Don), is an underexplored wild edible fruit of Indian Himalayan region, analyzed for total polyphenol contents, antioxidant, anti-elastase, anti-collagenase, and anti-tyrosinase activities using in vitro assays. High values of total phenolic contents of 1257 ± 40 mg gallic acid equivalents/100 g fruit weight and total flavonoid contents of 3501 ± 203 mg catechin equivalents/100 g fruit weight were observed. V. mullaha fruit extracts showed outstanding antioxidant activities (ABTS+, 1,1-diphenyl-2-picrylhydrazyl, superoxide anion, linoleate peroxyl radicals scavenging, and ferric reducing activities) and remarkable anti-elastase, anti-collagenase, and anti-tyrosinase activities. High resolution liquid chromatography–mass spectroscopy analysis revealed presence of 15 phenolic compounds, namely, chlorogenic acid, acetyl salicylic acid, dihydrorobinetin, dihydromyricetin, 2-isoprenylemodin, rutin, cosmosiin hexaacetate, pectolinarin, dihydroquercetin, eriodictyol, iriginol hexaacetate, theaflavin, epicatechin-pentaacetate, lomatin, and peucenin in fruit extracts. This study recommends utilization of V. mullaha fruit as functional food with prospective pharmaceutical, nutraceutical, and cosmeceutical properties.  相似文献   
68.
Collecting EEG signals in the IMPROVE data library   总被引:2,自引:0,他引:2  
One of the key issues for the IMPROVE (IMPROVing control of patient status in critical carE) project was to define and build a data library (DL) of annotated data acquired in the intensive-care unit (ICU), with particular reference to problems of mismatch between oxygen utilisation and supply. An additional aim of the IMPROVE study was to test the feasibility and clinical value of including limited monitoring of high-quality long-term EEG signals with the main DL in a restricted number of patients. Such an EEG DL would form a useful basis for testing the applicability and validity of different signal processing and interpretation methods in ICU monitoring, and also demonstrate the degree to which useful information could be obtained by a degree of fusion between systemic and cerebral variables. In this article, we describe the setup for collection of the EEG DL, the tools developed to facilitate visual analysis of the EEG together with simultaneous data from other non-EEG variables, data concerning quality control, and some preliminary observations from detailed visual assessment of EEG patterns in relation to other ICU events  相似文献   
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The application of three constrained, nonlinear optimization methods (method of multipliers, complex method and adaptive random search method) to six chemical process problems is described. Based on the numerical results, salient characteristics of the problems and the specific advantages of the methods are discussed. The multiplier method was implemented with numerical approximation to derivatives; the results show that both the increment (or perturbation) and the accuracy of floating-point numbers are important in determining the effect of numerical approximations on the performance of the method.  相似文献   
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