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31.
Silvia Knobloch‐Westerwick 《The Journal of communication》2012,62(4):628-642
Right before the 2008 U.S. presidential election, this 2‐session online field study examined consequences of selective exposure to political messages on accessibility of attitudes and of partisanship. In the first session, participants indicated attitudes toward political issues and their partisanship, which allowed measuring accessibility of attitudes and of partisanship. In the second session, participants browsed articles. Four issues were covered by 8 articles, with 2 articles featuring opposing perspectives. Selective exposure was unobtrusively logged. Finally, participants completed measures for attitudes and partisanship again. Selective exposure to attitude‐consistent articles was linked to greater attitude accessibility. The indirect impact of selective exposure on partisanship accessibility through attitude accessibility was significant. 相似文献
32.
Chun Lam Clement Chan Mlanie M. Bay Gianni Jacucci Roberto Vadrucci Cyan A. Williams Gea T. van de Kerkhof Richard M. Parker Kevin Vynck Bruno Frka‐Petesic Silvia Vignolini 《Advanced materials (Deerfield Beach, Fla.)》2019,31(52)
Hydroxypropyl cellulose (HPC) is a biocompatible cellulose derivative capable of self‐assembling into a lyotropic chiral nematic phase in aqueous solution. This liquid crystalline phase reflects right‐handed circular polarized light of a specific color as a function of the HPC weight fraction. Here, it is demonstrated that, by introducing a crosslinking agent, it is possible to drastically alter the visual appearance of the HPC mesophase in terms of the reflected color, the scattering distribution, and the polarization response, resulting in an exceptional matte appearance in solid‐state films. By exploiting the interplay between order and disorder, a robust and simple methodology toward the preparation of polarization and angular independent color is developed, which constitutes an important step toward the development of real‐world photonic colorants. 相似文献
33.
34.
Toschi F Orlanducci S Tamburri E Guglielmotti V Terranova ML Di Carlo A Reale A Falessi C 《Journal of nanoscience and nanotechnology》2010,10(12):8336-8340
The thermal performances of nanocomposite layers formed by Single-walled Carbon Nanotubes (SWCNT) dispersed in 2 different kind of polydimethyl-siloxane (PDMSO) matrices has been investigated by measuring the thermal resistance under conditions similar to the ones used for thermal management in microelectronics. A series of nanocomposite samples with thickness in the range 25 microm(-1) cm have been tested. The nanocomposites were prepared varying the amounts of nanotubes embedded in the matrix (from 0.1 to 5%w). In some cases also microsized graphites were mixed to the nanotube's fillers. For 25 micron thick layers, the thermal resistance of the neat silicone specimen can be reduced of 54% with the addition of 2%w carbon nanotubes. The variation of thermal conductivity as a function of the SWCNT's loading is reported and discussed. Furthermore the dispersion's effects of the nanotubes in the layers and the effects on the realization of a net-like system have been investigated. 相似文献
35.
Silvia Orsi Daniela Guarnieri Paolo A. Netti 《Journal of materials science. Materials in medicine》2010,21(3):1013-1020
The ability to genetically modify cells seeded inside synthetic hydrogel scaffolds offers a suitable approach to induce and
control tissue repair and regeneration guiding cell fate. In fact the transfected cells can act as local in vivo bioreactor,
secreting plasmid encoded proteins that augment tissue regeneration processes. We have realized a DNA bioactivated high porous
poly(ethylene glycol) (PEG) matrix by polyethyleneimine (PEI)/DNA complexes adsorption. As the design of the microarchitectural
features of a scaffold also contributes to promote and influence cell fate, we appropriately designed the inner structure
of gene activated PEG hydrogels by gelatine microparticles templating. Microarchitectural properties of the scaffold were
analysed by scanning electron microscopy. 3D cell migration and transfection were monitored through time-lapse videomicroscopy
and confocal laser scanning microscopy. 相似文献
36.
37.
Miriam Ortega Heras M. Dolores Rivero-Pérez Silvia Pérez-Magariño Carlos González-Huerta Mª Luisa González-Sanjosé 《European Food Research and Technology》2008,226(6):1485-1493
Microoxygenation is a wine-making technique consisting in the addition of small and controlled amounts of oxygen. This study
has examined the effect of this technique on the volatile composition of two red single variety wines during two successive
vintages. The microoxygenation treatment was applied at the end of alcoholic fermentation and before beginning malolactic
fermentation. Once the microoxygenation treatment had finished, wines were aged in new American oak barrels for 12 months.
The results obtained showed that the microoxygenation treatment did not cause significant changes in the varietal and fermentation
volatile compounds, however microoxygenation slowed down the extraction of some of the volatile compounds extracted from wood.
A varietal and vintage effect was also observed for some of the compounds studied. 相似文献
38.
Polysaccharides,oligosaccharides and nitrogenous compounds change during the ageing of Tempranillo and Verdejo sparkling wines 下载免费PDF全文
39.
Marieli Rosseto Cesar Vinicius Toniciolli Rigueto Karolynne Sousa Gomes Daniela Dal Castell Krein Raquel Aparecida Loss Aline Dettmer Neila Silvia Pereira dos Santos Richards 《Journal of the science of food and agriculture》2024,104(6):3185-3196
In the cheese industry, whey, which is rich in lactose and proteins, is underutilized, causing adverse environmental impacts. The fractionation of its components, typically carried out through filtration membranes, faces operational challenges such as membrane fouling, significant protein loss during the process, and extended operating times. These challenges require attention and specific methods for optimization and to increase efficiency. A promising strategy to enhance industry efficiency and sustainability is the use of enzymatic pre-treatment with the enzyme transglutaminase (TGase). This enzyme plays a crucial role in protein modification, catalyzing covalent cross-links between lysine and glutamine residues, increasing the molecular weight of proteins, facilitating their retention on membranes, and contributing to the improvement of the quality of the final products. The aim of this study is to review the application of the enzyme TGase as a pretreatment in whey protein filtration. The scope involves assessing the enzyme's impact on whey protein properties and its relationship with process performance. It also aims to identify both the optimization of operational parameters and the enhancement of product characteristics. This study demonstrates that the application of TGase leads to improved performance in protein concentration, lactose permeation, and permeate flux rate during the filtration process. It also has the capacity to enhance protein solubility, viscosity, thermal stability, and protein gelation in whey. In this context, it is relevant for enhancing the characteristics of whey, thereby contributing to the production of higher quality final products in the food industry. © 2023 Society of Chemical Industry. 相似文献
40.
Identification and characterisation of the proteins bound by specific phage‐displayed recombinant antibodies (scFv) obtained against Brazil nut and almond extracts 下载免费PDF全文