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961.
962.
Barricelli Barbara Rita Casiraghi Elena Dattolo Antonina Rizzi Alessandro 《Universal Access in the Information Society》2021,20(1):185-200
Universal Access in the Information Society - With the increasing spread and usage of Internet technologies, the challenge of ensuring Web accessibility for all, including anyone with a form of... 相似文献
963.
Francesca Tosetti Massimo Alessio Alessandro Poggi Maria Raffaella Zocchi 《International journal of molecular sciences》2021,22(9)
Enzymes, once considered static molecular machines acting in defined spatial patterns and sites of action, move to different intra- and extracellular locations, changing their function. This topological regulation revealed a close cross-talk between proteases and signaling events involving post-translational modifications, membrane tyrosine kinase receptors and G-protein coupled receptors, motor proteins shuttling cargos in intracellular vesicles, and small-molecule messengers. Here, we highlight recent advances in our knowledge of regulation and function of A Disintegrin And Metalloproteinase (ADAM) endopeptidases at specific subcellular sites, or in multimolecular complexes, with a special focus on ADAM10, and tumor necrosis factor-α convertase (TACE/ADAM17), since these two enzymes belong to the same family, share selected substrates and bioactivity. We will discuss some examples of ADAM10 activity modulated by changing partners and subcellular compartmentalization, with the underlying hypothesis that restraining protease activity by spatial segregation is a complex and powerful regulatory tool. 相似文献
964.
Ramiro Ariel Carciochi Leandro Galván D′Alessandro Guillermo Daniel Manrique 《International Journal of Food Science & Technology》2016,51(4):1018-1025
The effect of different roasting conditions on the antioxidant properties and the phenolic content of quinoa seeds was studied. Advanced and final products of the Maillard reaction were also quantified in order to evaluate the contribution to DPPH radical scavenging capacity and reducing power of samples. In general, response surface analysis showed significant increases in the phenolic content, the antioxidant activity and the level of Maillard reaction products (MRPs), mainly as processing temperature increased, while roasting time had a minor impact on these response variables. The highest antioxidant activity was achieved in extracts of quinoa seeds roasted at 190 °C for 30 min. Principal component analysis applied to the data suggested that MRPs had a greater contribution to antioxidant properties than phenolic compounds in the processed samples. These results demonstrated that roasted quinoa seeds/flour may be considered as a nontraditional ingredient with enhanced antioxidant capacity for the production of functional foods. 相似文献
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966.
The primary concern of the present paper is the regulation of an uncertain heat process with collocated boundary sensing and actuation. The underlying heat process is governed by an uncertain parabolic partial differential equation (PDE) with Neumann boundary conditions. It exhibits an unknown constant diffusivity parameter and it is affected by a smooth boundary disturbance, which is not available for measurements and which is possibly unbounded in magnitude. The proposed robust synthesis is formed by the linear feedback design and by the ”Twisting” second-order sliding-mode control algorithm, suitably combined and re-worked in the infinite-dimensional setting. A non-standard Lyapunov functional is invoked to establish the global asymptotic stability in a Sobolev space, involving spatial state derivatives of the same order as that of the plant equation. The stability proof is accompanied by a set of simple tuning rules for the controller parameters. The effectiveness of the developed control scheme is supported by simulation results. 相似文献
967.
Calabria Marco; Jacquin-Courtois Sophie; Miozzo Antonio; Rossetti Yves; Padovani Alessandro; Cotelli Maria; Miniussi Carlo 《Canadian Metallurgical Quarterly》2011,25(2):193
Objective: It has been proposed that time, space, and numbers share the same metrics and cortical network, the right parietal cortex. Several recent investigations have demonstrated that the mental number line representation is distorted in neglect patients. The aim of this study is to investigate the relationship between time and spatial configuration in neglect patients. Method: Fourteen right-brain damaged patients (six with neglect and eight without neglect), as well as eight age-matched healthy controls, performed a time discrimination task. A standard tone (short: 700 ms and long: 1,700 ms) had to be confronted in duration to a test tone. Test tone differed of 100, 200, and 300 ms respect to the standard tone duration. Results: Neglect patients performed significantly worse than patients without neglect and healthy controls, irrespective of the duration of the standard tone. Conclusion: These results support the hypothesis that mental representations of space and time both share, to some extent, a common cortical network. Besides, spatial neglect seems to distort the time representation, inducing an overestimation of time durations. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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970.
Ugo Becciani Vincenzo Antonuccio-Delogu Alessandro Costa Catia Petta 《Journal of Grid Computing》2012,10(2):265-277
While new infrastructures for large computational challenges begin to be widely accessible to researchers, computational codes
need to be re-designed to exploit new facilities. The Grid and the cloud computing concepts are changing the computational
resource distribution and availability, and much effort start to be made to develop new codes for a better exploitation of
new resources. This paper presents an example of the use of Grid resources, based on gLite middleware, to run cosmological
simulations, that, up to now, are normally executed on Supercomputers. We have also used the Grid to explore and visualize
the dataset. We discuss non particular the performance of FLY a parallel code implementing the octal-tree algorithm introduced
by J. Barnes and P. Hut to compute the gravitational field efficiently. It simulates the evolution of the collisionless component
of the material content of our Universe. FLY was originally developed to run on mainframe systems using the one-side communication
paradigm, but we are now presenting a modified version of the computational algorithm to exploit the Grid environment. We
also integrated the data exploration and visualization process on the Grid, to obtain preliminary results using the distributed
facilities. 相似文献