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排序方式: 共有2826条查询结果,搜索用时 31 毫秒
81.
Claudia Riccardi Federica DAria Filomena Anna Digilio Maria Rosaria Carillo Jussara Amato Dominga Fasano Laura De Rosa Simona Paladino Mariarosa Anna Beatrice Melone Daniela Montesarchio Concetta Giancola 《International journal of molecular sciences》2022,23(9)
A set of guanine-rich aptamers able to preferentially recognize full-length huntingtin with an expanded polyglutamine tract has been recently identified, showing high efficacy in modulating the functions of the mutated protein in a variety of cell experiments. We here report a detailed biophysical characterization of the best aptamer in the series, named MS3, proved to adopt a stable, parallel G-quadruplex structure and show high nuclease resistance in serum. Confocal microscopy experiments on HeLa and SH-SY5Y cells, as models of non-neuronal and neuronal cells, respectively, showed a rapid, dose-dependent uptake of fluorescein-labelled MS3, demonstrating its effective internalization, even in the absence of transfecting agents, with no general cytotoxicity. Then, using a well-established Drosophila melanogaster model for Huntington’s disease, which expresses the mutated form of human huntingtin, a significant improvement in the motor neuronal function in flies fed with MS3 was observed, proving the in vivo efficacy of this aptamer. 相似文献
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83.
Roberto Moreno Soriano Nuria Rojas Emilio Nieto Rosa de Guadalupe González-Huerta Juan Manuel Sandoval-Pineda 《International Journal of Hydrogen Energy》2021,46(51):25944-25953
To keep optimally connected, all electrolysis cell elements is one of the most important design criteria. The optimal distribution of the clamping points is crucial to increasing cell performance. In this work, the compression pressure distribution inside of a 25 cm2 PEM electrolysis cell was evaluated, using different materials: Teflon®, Viton®, ethylene propylene diene monomer rubber (EPDM), and nitrile rubber. Sealing material evaluation was performed taking as performance indicators: total compressed area (%) and compression pressure, for different torques applied. Pressure distribution was obtained by using pressure-sensitive films, analyzing the distribution of pressure points from three-dimensional plots (3D), and quantifying intensities of the images obtained. Results showed that pressure points distribution depends on the stiffness and thickness of the gasket materials. For a tightening torque of 3.70 N m, a pressure of 2.23 MPa is obtained with 85% of the membrane area compressed using nitrile rubber-EPDM gaskets. 相似文献
84.
Claudio De Rosa Finizia Auriemma Nella Galotto Galotto Rocco Di Girolamo 《Polymer》2012,53(12):2422-2428
A study of the crystallization of the mesomorphic form of isotactic polypropylene (iPP) in samples of different stereoregularity prepared with metallocene catalysts is presented. Contrary to what claimed in the literature, we have found that the mesomorphic form can be obtained by quenching of the melt at 0 °C also in the case of low stereoregular samples, provided that the samples are kept at 0 °C for long time. The key is the formation of mesomorphic bundles with chains in ordered 3/1 helical conformation of size large enough to be stable and inhibit the crystallization of the α form at room temperature. For stereoirregular samples the concentration of long ordered helical stretches is low and this requires long residence time at 0 °C for the formation of mesomorphic aggregates of size larger than the critical size. This result provides evidence that the mesomorphic aggregates are not formed as a result of a cooperative process driven by entropy, as in the case of liquid crystals, but rather they form via a nucleation and growth mechanism, as in the normal crystallization processes, according to the idea that the mesophase of iPP is a highly defective crystalline form. 相似文献
85.
Rosa Franquet i Calvet Maria Isabel Villa Montoya Ignacio Bergillos García 《Journal of Computer-Mediated Communication》2013,18(3):378-397
This article analyses public service broadcasting in Europe, looking at public broadcasters' role as promoters of participative processes. Computer‐mediated communication and studies rooted in mediated human interactivity are used to explore participative elements provided by digital technology, and how these can be incorporated into the news websites, through an empirical study of 5 case studies in the European market. The analysis is based on the methodology of content analysis with the goal of outlining the particularities of the participative elements implemented by each broadcaster and revealing the most common participative strategies. The findings suggest that although public service broadcasters offer a wide variety of possibilities, encouraging audiences to take on more active roles, their role is still peripheral and complementary. 相似文献
86.
87.
María V. Fernández Rosa J. Jagus Sandra L. Mugliaroli 《Food and Bioprocess Technology》2014,7(9):2528-2537
The effect of nisin alone and in combination with Microgard? on the natural microbial flora of ricotta cheese and in post-process contamination with Listeria innocua was studied. Microbial groups studied were mesophilic, psychrotrophic, proteolytic, lactic acid and coliform bacteria, and total molds and yeasts. Considering the evolution of all microbial groups and failure criteria adopted for mesophilic and coliform bacteria, this product reached the end of its shelf life before 5 days, which is insufficient time for product commercialization. The combined use of nisin and Microgard? proved to be more effective than the individual application on these microbial groups, resulting in a 13 days shelf life extension. Additionally, the combined treatment reduced the growth of L. innocua as a post-process contamination. 相似文献
88.
J.A. García Rosa Rodriguez-Sánchez J. Fdez-Valdivia A. Garrido 《Signal Processing: Image Communication》2012,27(1):39-53
In progressive image transmission, there exist some risks which may appear during the processing. A first class of risks is the diminishing coding performance when the occurrence of insignificant coefficients at each transmission time is a small-probability event. It may be a catastrophic transmission risk which can lead to major and irreversible bit losses. In a second class of risks, the performance of the transmission technique diminishes though the occurrence of insignificant sample is still a large-probability event.This paper shows a “Test of Transmission Risks” which can be used to analyze, for a given image, the performance of the state of the art in progressive transmission from the viewpoint of the catastrophic transmission risks. To this aim we make use of a decision making tool based on axioms requiring sensitivity to coding situations where the occurrence of insignificant sample at the transmission time may be either a small-probability or a large-probability event. 相似文献
89.
Guilherme Galante Luis Carlos Erpen De Bona Antonio Roberto Mury Bruno Schulze Rodrigo da Rosa Righi 《Journal of Grid Computing》2016,14(2):193-216
Elasticity can be seen as the ability of a system to increase or decrease the computing resources allocated in a dynamic and on demand way. It is an important feature provided by cloud computing, that has been widely used in web applications and is also gaining attention in the scientific community. Considering the possibilities of using elasticity in this context, a question arises: “Are the available public cloud solutions suitable to provide elasticity to scientific applications?” To answer the question, in a first moment we present a survey on the use of cloud computing in scientific scenarios, providing an overview of the subject. Next, we describe the elasticity mechanisms offered by major public cloud providers and analyzes the limitations of the solutions in providing elasticity for scientific applications. As the main contribution of the article, we also present an analysis over some initiatives that are being developed to overcome the current challenges. In our opinion, current computational clouds are developing rapidly but have not yet reached the necessary maturity level to meet all scientific applications elasticity requirements. We expect that in the coming years the efforts being taken by numerous researchers in this area identify and address these challenges and lead to better and more mature technologies that will improve cloud computing practices. 相似文献
90.