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31.
32.
María Alba Pilar Formentín Josep Ferré-Borrull Josep Pallarès Lluís F Marsal 《Nanoscale research letters》2014,9(1):411
We report on the fabrication of polyelectrolyte multilayer-coated hollow silicon dioxide micropillars as pH-responsive drug delivery systems. Silicon dioxide micropillars are based on macroporous silicon formed by electrochemical etching. Due to their hollow core capable of being loaded with chemically active agents, silicon dioxide micropillars provide additional function such as drug delivery system. The polyelectrolyte multilayer was assembled by the layer-by-layer technique based on the alternative deposition of cationic and anionic polyelectrolytes. The polyelectrolyte pair poly(allylamine hydrochloride) and sodium poly(styrene sulfonate) exhibited pH-responsive properties for the loading and release of a positively charged drug doxorubicin. The drug release rate was observed to be higher at pH 5.2 compared to that at pH 7.4. Furthermore, we assessed the effect of the number of polyelectrolyte bilayers on the drug release loading and release rate. Thus, this hybrid composite could be potentially applicable as a pH-controlled system for localized drug release. 相似文献
33.
Valderrama Pilar Escabias Manuel Jiménez-Contreras Evaristo Valderrama Mariano J. Baca Pilar 《Scientometrics》2018,116(2):1203-1212
Scientometrics - In order to estimate the impact factor value for a journal in Dentistry, two sets of variables were considered in this study: the first takes in the longitudinal behavior of the... 相似文献
34.
Daniele da Silva Bastos Maria do Pilar Gonçalves Cristina Tristão de Andrade Kátia Gomes de Lima Araújo Maria Helena Miguez da Rocha Leão 《Food and Bioproducts Processing》2012,90(4):683-692
The aim of this work was to obtain a new stable food product from cashew apple juice encapsulated by spray-drying technique using chitosan–whey protein isolate systems. The materials were evaluated according to their physicochemical stability during storage at different conditions and characterized with respect to their particle size distribution and structure. Encapsulated commercial and natural juices showed homogenous and unimodal particle size distribution with diameters ranging from 0.2 to 5.0 μm and from 0.2 to 40.0 μm, respectively. Both juices demonstrated higher physicochemical stability for vitamin C and color measurements than their respective non-encapsulated juices. X-ray diffractograms evidenced that the powder juices after the 140th day of storage were still in amorphous state. These results indicate that the new product was effective in protecting sensitive compounds present in the food matrix and it was also able to remain stable throughout the study period. 相似文献
35.
Isaac Pinyol Jordi Sabater-Mir Pilar Dellunde Mario Paolucci 《Autonomous Agents and Multi-Agent Systems》2012,24(1):175-216
Computational trust and reputation models have been recognized as one of the key technologies required to design and implement
agent systems. These models manage and aggregate the information needed by agents to efficiently perform partner selection
in uncertain situations. For simple applications, a game theoretical approach similar to that used in most models can suffice.
However, if we want to undertake problems found in socially complex virtual societies, we need more sophisticated trust and
reputation systems. In this context, reputation-based decisions that agents make take on special relevance and can be as important
as the reputation model itself. In this paper, we propose a possible integration of a cognitive reputation model, Repage,
into a cognitive BDI agent. First, we specify a belief logic capable to capture the semantics of Repage information, which
encodes probabilities. This logic is defined by means of a two first-order languages hierarchy, allowing the specification
of axioms as first-order theories. The belief logic integrates the information coming from Repage in terms if image and reputation,
and combines them, defining a typology of agents depending of such combination. We use this logic to build a complete graded
BDI model specified as a multi-context system where beliefs, desires, intentions and plans interact among each other to perform
a BDI reasoning. We conclude the paper with an example and a related work section that compares our approach with current
state-of-the-art models. 相似文献
36.
37.
María del Pilar Monge Alejandra Paola Magnoli Maria Virginia Bergesio Nestor Tancredi Carina E. Magnoli 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(6):1043-1052
Aflatoxin B1 (AFB1) and fumonisin B1 (FB1) are mycotoxins that often co-occur in feedstuffs. The ingestion of AFB1 causes aflatoxicosis in humans and animals. Sodium bentonite (NaB), a cheap non-nutritive unselective sequestering agent incorporated in animal diets, can effectively prevent aflatoxicosis. Fumonisins are responsible for equine leukoencephalomalacia and porcine pulmonary oedema, and often have subclinical toxic effects in poultries. Fumonisin B1 and aflatoxin B1 are both strongly adsorbed in vitro on sodium bentonite. Co-adsorption studies, carried out with a weight ratio of FB1 to AFB1 that mimics the natural occurrence (200:1), showed that FB1 greatly decreases the in vitro ability of NaB to adsorb AFB1. The ability of two activated carbons to adsorb FB1 was also investigated. Both carbons showed high affinity for FB1. A complex behaviour of the FB1 adsorption isotherms with pH was observed. In vitro results suggest that under natural contamination levels of AFB1 and FB1, a mixture of activated carbon and sodium bentonite might be potentially useful for prevention of sub-acute aflatoxicosis. 相似文献
38.
The trans as well as the cis C16:1 isomer profiles were established in 43 ewe milk fats supplemented with different dietary lipid sources representative of the variety of unsaturated fatty acids found in nature such as olive, sunflower, linseed and fish oils. Fractionation by silver-ion solid phase extraction facilitated a rapid separation of the trans, cis and saturated FA before gas chromatography analysis took place. C16:1 isomers with a double bond in positions 7, 9 and 13 in the cis group and 8 and 9 in the trans fraction were the most abundant. Dietary lipid supplementation produced a noticeable increase in the total trans C16:1 content and elevated correlations were observed between trans-8 C16:1 and trans-10 C18:1 as well as trans-9 C16:1 and trans-11 C18:1. These results support the idea that altering the trans C18:1 profile affects trans C16:1 isomer composition consistent with the β-oxidation products from the trans C18:1 isomers. 相似文献
39.
Wong Ademar Materón Elsa María Freitas Tayane A. Faria Ronaldo C. Gonçalves Débora Del Pilar Taboada Sotomayor Maria 《Journal of Applied Electrochemistry》2022,52(8):1249-1257
Journal of Applied Electrochemistry - The present work reports the development of screen-printed electrode (SPE) using flexible polyester sheets modified with nanodiamond (ND), Au nanoparticles... 相似文献
40.
M Pilar Cano Begoa de Ancos M Gloria Lobo Marianne Monreal 《Journal of the science of food and agriculture》1996,71(3):351-358
The predominant carotenoids in extracts of female and hermaphrodite Papaya fruits (Carica papaya L) Solo cv Sunrise were determined by high-performance liquid chromatography on a C18 reversed-phase column using a diode-array detector. Three classes of carotenoids were separated and identified from the papaya extract without saponification; these were xanthophylls, hydrocarbon carotenoids and carotenol fatty acid esters. The xanthophylls were identified as trans-zeaxanthin, cryptoflavin and β-cryptoxanthin; other xanthophyls were detected in very small quantities. The major hydrocarbon carotenoid was identified as lycopene. Carotenol fatty acid esters were identified as carotenol fatty acid esters of β-cryptoxanthin, cryptoxanthin-5,6-epoxide, lutein, zeaxanthin and violaxanthin. There were no qualitative differences among the carotenoid pattern of female and hermaphrodite papaya fruits. Changes in carotenoid composition during ripening in hermaphrodite and female papaya fruits (cv Sunrise) were investigated in three different stages of ripeness. These changes could be shown in terms of Hunter colour values. 相似文献