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411.
Leonid I. Muravsky Olexander M. Sakharuk Liliana Byczkowska-Lipińska 《Optics and Lasers in Engineering》2009,47(6):712-720
An optical speckle-displacement correlator based on hybrid optical–digital joint transform correlator architecture with a digital first stage and an optical second stage has been used to determine the correlation peak position with subpixel accuracy, without the use of intricate interpolation algorithms. A thorough analysis and a calculation of the parameters of the second optical stage are performed in order to achieve the necessary magnification of the correlation peak, so as to obtain an accurate definition of the peak position. The experiment setup for the realization of the optical speckle-displacement technique was constructed with a digital Fourier processor as its basic component, making possible a joint power spectrum median and ring median binarization, and an optical Fourier processor. The results which were obtained demonstrate that a setup of this kind can produce sharp and narrow correlation peaks, and can provide the necessary magnification for finding the peak position with subpixel accuracy. 相似文献
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In this study, we aimed to use as a new lignocellulosic precursor in the production of activated carbon. The physicochemical characteristics of the activated carbons obtained under optimum conditions were determined by using some techniques such as thermo-gravimetric (TG/DTG) analysis, nitrogen adsorption–desorption, scanning electron microscopy (SEM) and surface functional group analysis by Fourier transform infrared spectroscopy (FT-IR), Boehm titration method and point of zero charge (pHpzc). In addition, the activated carbons were tested to remove phenols from aqueous solutions. The results indicated that activated carbon the orange peel, pine cone and yerba mate, could be employed as an alternative low-cost activated carbon for the removal the phenolic contaminants from wastewater. 相似文献
415.
Claudia Valentina Popa Liliana Lungu Ligia Florentina Cristache Crinu Ciuculescu Andrei Florin Danet 《Natural product research》2015,29(18):1744-1747
To gain new insight into the antimicrobial potential of Ailanthus altissima Swingle, ethanol leaf extracts were evaluated for the antifungal effects against the model yeast Saccharomyces cerevisae. The extracts inhibited the yeast growth in a dose-dependent manner, and this effect could be augmented by heat shock, exposure to visible light or exposure to high concentrations of Ca2+. Using transgenic yeast cells expressing the Ca2+-dependent photoprotein, aequorin, it was found that the leaf extracts induced cytosolic Ca2+ elevation. Experiments on yeast mutants with defects in Ca2+ transport demonstrated that the cytotoxicity of the A. altissima leaf extracts (AaLEs) was mediated by transient pulses of Ca2+ ions which were released into the cytosol predominantly from the vacuole. The investigation of the antifungal synergies involving AaLEs may contribute to the development of optimal and safe combination therapies for the treatment of drug-resistant fungal infections. 相似文献
416.
Lukas Gritsch Liliana Liverani Christopher Lovell Aldo R. Boccaccini 《Macromolecular bioscience》2020,20(3)
Inducing the formation of new blood vessels (angiogenesis) is an essential requirement for successful tissue engineering. Approaches have been proposed to enhance angiogenesis using growth factors and other biomolecules; however, this approaches present drawbacks in terms of high cost and patient safety. Copper is known to effectively regulate angiogenesis and can offer a more cost‐effective alternative than the direct use of growth factors. With this study, a strategy to incorporate copper in electrospun fibrous scaffolds with pro‐angiogenic properties is presented. Polycaprolactone (PCL) and copper(II)‐chitosan are electrospun using benign solvents. The morphological and physicochemical properties of the fiber mats are investigated through scanning electron microscopy (SEM), static contact angle measurements, energy dispersive X‐ray, and Fourier‐transform infrared spectroscopies. Scaffold stability in phosphate buffered saline at 37 °C is monitored over 1 week. A bone marrow stromal cell line (ST‐2) is cultured for 7 days and its behavior is evaluated using SEM, fluorescence microscopy and a tetrazolium salt‐based colorimetric assay. Results confirm that PCL/copper(II)‐chitosan is suitable for electrospinning. The fiber mats are biocompatible and favor cell colonization and infiltration. Most notably, the angiogenic potential of PCL/copper(II)‐chitosan blends is confirmed by a three‐fold increase in VEGF secretion by ST‐2 cells in the presence of copper(II)‐chitosan. 相似文献
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Sean Quinlan Dmitri Chvedov Liliana N. Trevani Peter R. Tremaine 《Journal of solution chemistry》2015,44(5):1121-1140
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María L. Novoa Yelisbeth Escalante Liliana Maldonado Iván Galindo-Castro Annamil Álvarez Katherine Figarella 《Natural product research》2015,29(3):207-212
13,14-Dihydroxy-8,11,13-podocarpatrien-7-one (1) and a series of ring C aromatic diterpene derivatives were synthesised from (+)-manool (4) and evaluated for their cytotoxic, leishmanicidal and trypanocidal activities. Our results indicated that compound 1 and other podocarpane-type intermediates are cytotoxic. Cleavage of C6–C7 bond of compound 7 improved cytotoxic activity, indicating that, in particular, the 6,7-seco-podocarpane-type compound 20 might serve as a lead compound for further development. 相似文献