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71.
Edible films based on high molecular weight chitosan (CH) and methylcellulose (MC) were obtained by mixing different ratios (0:1, 0.5:1.5, 1.0:1.0, 1.5:0.5 and 1:0) of the biopolymers in two solvent conditions (0.95 and 6.85 mmol of ions per g polymer). In order to characterize the dry films, water sorption isotherms, water vapour permeability and film microstructure were evaluated. Water vapour permeability of CH-MC composite films was significantly affected by both the CH-MC ratio and the ionic concentration in the matrix. This can be attributed to the influence of ions on polymer chain packaging during the film formation and their role in the water uptake capacity of the films which affects the water transport properties. 相似文献
72.
Joana Silva Celso Alves Alice Martins Patrícia Susano Marco Simes Miguel Guedes Stephanie Rehfeldt Susete Pinteus Helena Gaspar Amrico Rodrigues Mrcia Ines Goettert Amparo Alfonso Rui Pedrosa 《International journal of molecular sciences》2021,22(4)
Parkinsons Disease (PD) is the second most common neurodegenerative disease worldwide, and is characterized by a progressive degeneration of dopaminergic neurons. Without an effective treatment, it is crucial to find new therapeutic options to fight the neurodegenerative process, which may arise from marine resources. Accordingly, the goal of the present work was to evaluate the ability of the monoterpenoid lactone Loliolide, isolated from the green seaweed Codium tomentosum, to prevent neurological cell death mediated by the neurotoxin 6-hydroxydopamine (6-OHDA) on SH-SY5Y cells and their anti-inflammatory effects in RAW 264.7 macrophages. Loliolide was obtained from the diethyl ether extract, purified through column chromatography and identified by NMR spectroscopy. The neuroprotective effects were evaluated by the MTT method. Cells’ exposure to 6-OHDA in the presence of Loliolide led to an increase of cells’ viability in 40%, and this effect was mediated by mitochondrial protection, reduction of oxidative stress condition and apoptosis, and inhibition of the NF-kB pathway. Additionally, Loliolide also suppressed nitric oxide production and inhibited the production of TNF-α and IL-6 pro-inflammatory cytokines. The results suggest that Loliolide can inspire the development of new neuroprotective therapeutic agents and thus, more detailed studies should be considered to validate its pharmacological potential. 相似文献
73.
Energy-saving scheduling on IaaS HPC cloud environments based on a multi-objective genetic algorithm
Vila Sergi Guirado Fernando Lerida Josep L. Cores Fernando 《The Journal of supercomputing》2019,75(3):1483-1495
The Journal of Supercomputing - Nowadays, cloud computing is a growing scenario applied to many scientific and manufacturing areas due to its flexibility for adapting to highly demanding computing... 相似文献
74.
Ricardo Almeida de Siqueira Daniel Vila 《International journal of remote sensing》2019,40(11):4244-4263
Rainfall measurement is a very important topic to society and for the understanding of the weather and climate, therefore needs to be calculated as accurately as possible. Counteracting the problem of the high temporal and spatial variability of precipitation, geostationary satellites sensors have been proved an excellent tool to this task, providing scans with high temporal resolution and detecting the growth and decay of rain cells. Using infra-red (IR) images obtained from the Geostationary Operational Environmental Satellites (GOES), the Hydro-Estimator (HYDRO) algorithm produces instantaneous precipitation estimates with 30 min temporal resolution and 4 km spatial resolution with a very low latency compared with other more sophisticated methodologies (i.e. passive microwave-based algorithms). However, the IR algorithm has some limitations to estimate precipitation on some cloud systems. In order to overcome this problem, the main objective of this study is to develop a light and fast algorithm, based on the histogram matching (HM) technique, to combine the superior sampling and low latency of the HYDRO IR product with more accurate active microwave-based products over Brazil. The adjusted HYDRO (AHYDRO) product was validated against Brazil rain gauge network for two years (2016–2017) and the performance was assessed by using standard statistical metrics and categorical indices. Results show that the HM technique is able to minimize the large variability and discrepancies among HYDRO and observed precipitation over Brazil. At same time, is able to generate a better bias performance while maintaining the same correlation levels before the adjustment. 相似文献
75.
76.
Fitó M Covas MI Lamuela-Raventós RM Vila J Torrents L de la Torre C Marrugat J 《Lipids》2000,35(6):633-638
The protective effect of phenolic compounds from an olive oil extract, and of olive oils with (extra-virgin) and without (refined)
phenolic components, on low density lipoprotein (LDL) oxidation was investigated. When added to isolated LDL, phenolics [0.025–0.3
mg/L caffeic acid equivalents (CAE)] increased the lag time of conjugated diene formation after copper-mediated LDL oxidation
in a concentration-dependent manner. Concentrations of phenolics greater than 20 mg/L inhibited formation of thiobarbituric-acid
reactive substances after AAPH-initiated LDL oxidation. LDL isolated from plasma after preincubation with phenolics (25–160
mg/L CAE) showed a concentration-dependent increase in the lag time of conjugated diene formation after copper-mediated LDL
oxidation. Refined olive oil (0 mg/L CAE) and extra-virgin olive oil (0.1 and 0.3 mg/L CAE) added to isolated LDL caused an
increase in the lag time of conjugated diene formation after copper-mediated LDL oxidation that was related to olive oil phenolic
content. Multiple regression analysis showed that phenolics were significantly associated with the increase in lag time after
adjustment for effects of other antioxidants; α-tocopherol also achieved a statistically significant effect. These results
indicate that olive oil phenolic compounds protect LDL against peroxyl radical-dependent and metal-induced oxidation in vitro and could associate with LDL after their incubation with plasma. Both types of olive oil protect LDL from oxidation. Olive
oil containing phenolics, however, shows more antioxidant effect on LDL oxidation than refined olive oil. 相似文献
77.
In this paper we present experimental data on the temperature dependence of the electrical conductivity, σ, in nine different imidazolium based ionic liquids. We have measured four 1-(alkyl chain)-3-methyl imidazolium tetrafluoroborate (CnMIM-BF4) ionic liquids, with Cn representing ethyl, butyl, hexyl and octyl chains, to study the dependence of σ with the cation length. Moreover, to study the influence of the anion size in the electrical conductivity, we measured six different EMIM-X, with X being, from smaller to bigger sizes, Cl−, Br−, BF4−, PF6−, ethyl sulfate and tosylate. The measurements were performed at atmospheric pressure, and the studied temperature range covers the liquid phase of the analyzed compounds. We have fitted the electrical conductivity data of the nine ionic liquids using a Vogel-Tamman-Fulcher (VTF) equation with high precision. We observe from the measured data that the electrical conductivity decreases its value as the alkyl chain of the cation increases. In contrast, we do not observe that dependence with the anion size, where there seems to be an optimal size (that of BF4−) for which σ reaches its maximum value, being lower for smaller or bigger anion sizes. Finally, if we plot the natural logarithm of σ versus the distance in temperature to the glass transition one for each IL, we observe that the resulting straight lines are ordered with the anion (or cation) sizes for all nine compounds measured, i.e., lower σ values for bigger sizes. 相似文献
78.
Alba García-Rodríguez Laura Vila Constanza Cortés Alba Hernández Ricard Marcos 《Particle and fibre toxicology》2018,15(1):33
Background
The biological effects of nanoparticles depend on several characteristics such as size and shape that must be taken into account in any type of assessment. The increased use of titanium dioxide nanoparticles (TiO2NPs) for industrial applications, and specifically as a food additive, demands a deep assessment of their potential risk for humans, including their abilities to cross biological barriers.Methods
We have investigated the interaction of three differently shaped TiO2NPs (nanospheres, nanorods and nanowires) in an in vitro model of the intestinal barrier, where the coculture of Caco-2/HT29 cells confers inherent intestinal epithelium characteristics to the model (i.e. mucus secretion, brush border, tight junctions, etc.).Results
Adverse effects in the intestinal epithelium were detected by studying the barrier’s integrity (TEER), permeability (LY) and changes in the gene expression of selected specific markers. Using Laser Scanning Confocal Microscopy, we detected a different behaviour in the bio-adhesion and biodistribution of each of the TiO2NPs. Moreover, we were able to specifically localize each type of TiO2NPs inside the cells. Interestingly, general DNA damage, but not oxidative DNA damage effects, were detected by using the FPG version of the comet assay.Conclusions
Results indicate different interactions and cellular responses related to differently shaped TiO2NPs, nanowires showing the most harmful effects.79.
Esterification of Kraft lignin as a method to improve structural and mechanical properties of lignin‐polyethylene blends
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Lignin is a promising candidate for blends with thermoplastic polymers. Still, this endeavour is a challenge due to poor compatibility between both components. In this article, the effect of lignin esterification on the improvement of the compatibility between hardwood Kraft lignin and high‐density polyethylene (PE‐HD) is investigated. For this purpose, lignin was esterified with acetic, propionic, and butyric anhydride; its amount in the blends varied from 10 to 40%. Light microscopic images of blends show a reduction in particle size and a more homogeneous distribution with increasing length of the ester carbon chains (C2 to C4). Modification of lignin enhances the moduli and strength characteristics of the blends. Butyrated lignin performs best, as tensile strength of blends can be retained near that of pure PE‐HD with up to 40% lignin content. An additional investigation of unmodified lignin with reduced particle size confirms that modification is the decisive factor to enhance blend properties; a sole reduction of particle size is insufficient. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44582. 相似文献
80.
Santamariña-Rubio E Pérez K Ricart I Arroyo A Castellà J Borrell C 《Accident; analysis and prevention》2007,39(1):1-5
The objective is to describe injuries of road traffic deaths in Barcelona and identify injury profiles by road user type, through a cross-sectional study including road traffic deaths for the period 1997-2004. The data source was the Institut de Medicina Legal de Catalunya. Diagnoses were coded using the International Classification of Diseases, 9th revision, Clinical Modification, and classified using the Barell Matrix. Of the 719 deaths studied, 45% were pedestrians, 32% two wheel motor vehicle users, and 23% car occupants. The injury profile of the road traffic deaths in Barcelona is internal injuries and fractures to the torso and to the head/neck. This profile is repeated in all the road user groups, although pedestrians present higher frequencies of fractures and contusions to extremities and contusions to the head/neck, and fewer internal torso injuries than car occupants or two wheel motor vehicle users. 相似文献