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991.
We propose a new GIS-based procedure to retrieve archaeological elements using satellite remote sensing. The processing of multispectral satellite images consists in a preprocessing phase using the pansharpening technique to improve the spatial quality and in the exploitation of linear equations of the initial spectral bands with the aim of generating accurate and precise raster data that can be used as input for an object classification. The proposed methodology has been tested in an archaeological area located on the north-west flank of Etna volcano (Sicily, Italy).  相似文献   
992.
The present work investigated the effect of Polylactic acid (PLA) fibers produced by centrifugal spinning with incorporated BaTiO3 particles to improve their bacteriostatic behavior. The PLA matrix and three composites, presenting three different amounts of fillers, were subjected to UV/O3 treatment monitoring the possible modifications that occurred over time. The morphological and physical properties of the surfaces were characterized by different microscopic techniques, contact angle, and surface potential measurements. Subsequently, the samples were tested in vitro with human dermal fibroblasts (HDF) to verify the cytotoxicity of the substrates. No significant differences between the PLA matrix and composites emerged; the high hydrophobicity of the fibers, derived by the polymer structure, represented an obstacle limiting the fibroblast attachment. Samples underwent bacterial exposure (Staphylococcus epidermidis) for 12 and 24 h. Increasing the concentration of BT, the number of living bacteria and their distribution decreased in comparison with the PLA matrix suggesting an effect of the inorganic filler, which generates a neutralization effect leading to reactive oxygen species (ROS) generation and subsequently to bacterial damages. These results suggest that the barium titanate (BT) fillers clearly improve the antibacterial properties of PLA fibers after aging tests made before bacterial exposure, representing a potential candidate in the creation of composites for medical applications.  相似文献   
993.
Rega  Giuseppe  Settimi  Valeria 《Nonlinear dynamics》2021,103(2):1259-1303
Nonlinear Dynamics - In about the last two decades, global nonlinear dynamics has been evolving in a revolutionary way, with the development of sophisticated techniques employing concepts/tools of...  相似文献   
994.
Meccanica - The characterization and reproduction of tyre behaviour for vehicle modelling is a topic of particular interest both for real-time driver in the loop simulations and for offline...  相似文献   
995.
Burlon  Andrea  Alotta  Gioacchino  Di Paola  Mario  Failla  Giuseppe 《Meccanica》2021,56(4):769-784
Meccanica - This work deals with viscoelastic constitutive models involving variable-order fractional operators. There exist two main fractional models in the literature representing the...  相似文献   
996.
Phenols ( I ) are extremely relevant chemical functionalities in natural, synthetic and industrial chemistry. Their corresponding electron-rich anions, namely phenolates ( I ), are characterized by interesting physicochemical properties that can be drastically altered upon light excitation. Specifically, phenolates ( I ) become strong reducing agents in the excited state and are able to generate reactive radicals from suitable precursors via single-electron transfer processes. Thus, these species can photochemically trigger strategic bond-forming reactions, including their direct aromatic C−H functionalization. Moreover, substituted phenolate anions can act as photocatalysts to enable synthetically useful organic transformations. An alternative mechanistic manifold is represented by the ability of phenolate derivatives I to form ground state electron donor-acceptor (EDA) complexes with electron-poor radical sources. These complementary scenarios have paved the way for the development of a wide range of relevant organic reactions. In this Minireview, we present the main examples of this research field, and give insight on emerging trends in phenols photocatalysis towards richer organic synthesis.  相似文献   
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A rapid resolution liquid chromatography-tandem mass spectrometry analysis was applied to human urine samples to discover new molecular biomarkers of the alteration of psychophysical well-being due to the environmental, physiological and confinement stress conditions achieved in the MARS500 project. Urine samples of crew members were submitted to metabolomic studies by means of separative techniques coupled with mass spectrometric techniques and data analysis. More than 2,000 metabolite features were found in each comparison, and more than 150 metabolites were identified for every differential analysis. Significant modifications in eight metabolites were shared by the subjects under study.  相似文献   
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