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1.
Olivia V. López Leda Giannuzzi Noemí E. Zaritzky M. Alejandra García 《Materials science & engineering. C, Materials for biological applications》2013,33(3):1583-1591
Active starch films with glycerol and potassium sorbate were obtained by casting. Native and acetylated corn starches, as well as the mixture of them in equal proportions were used and filmogenic suspensions with pH 4.5 were also prepared. Sorbate concentration decreased during film storage due to its oxidative degradation. Active films resulted more yellow and less transparent than films without sorbate. The minimum inhibitory concentration of sorbate resulted 0.3%, regardless of the starch type and the formulation pH. The use of antimicrobial package was more effective to prevent microbial growth on food surfaces than the use of conventional methods. Additive kinetic release was neither affected by the starch type nor by the formulation pH. Sorbate diffusion process was mathematically modeled satisfactorily. Active films were able to inhibit Candida spp., Penicillium spp., S. aureus and Salmonella spp. growth. Active films extended 21% the shelf life of refrigerated cheese, regardless of the formulation pH. 相似文献
2.
Using Combined Bipolar Semantic Scales and Eye‐Tracking Metrics to Compare Consumer Perception of Real and Virtual Bottles
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Juan‐Carlos Rojas Manuel Contero Noemí Bartomeu Jaime Guixeres 《Packaging Technology and Science》2015,28(12):1047-1056
Three‐dimensional virtual representations of consumer products are expected to gain relevance in e‐commerce applications as low cost virtual reality headsets arrive on the market in the next years. However, there are a limited number of studies related to the perceptual evaluation of virtual products and their packaging where virtual and real (photographic) representations are compared. As part of an extensive exploration toward understanding product perception in virtual stores, this work presents a study with 38 participants in which consumer perceptions of a photographic and a virtual representation of a beer bottle are examined. Perceptual evaluation is assessed using two metrics: first, an evaluation was performed by applying a bipolar semantic scale based on four axes: novelty, resolution, style and emotion. Second, eye‐tracking metrics were employed to analyse participant gaze behaviour during the visualization of stimuli. Virtual bottles were modelled using a medium polygonal load (5 K polygons per bottle), and render quality was also medium to intentionally recreate the computing limitations of smartphone‐based virtual reality headsets. Results show that a medium render quality alters consumer perception and responses using semantic scales. Eye‐tracking analysis confirms that the orientation of the bottle and how it is presented also affect consumer perception. While some orientations result in similar eye‐tracking metrics, others show different results. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
3.
Ramón J. Durán Ignacio de Miguel Noemí Merayo Patricia Fernández Juan Carlos Aguado Rubén M. Lorenzo Evaristo J. Abril 《Photonic Network Communications》2009,17(1):21-33
A new method to design logical topologies based on genetic algorithms is presented. Not only does the algorithm determine
which nodes should be connected by means of lightpaths with the aim of minimizing congestion, but it also solves the routing
and wavelength assignment problem. In this way, the algorithm guarantees that the logical topology obtained can be embedded
in the optical network subject to the available set of resources. The algorithm is effective in terms of both congestion and
fairness. For instance, when compared with other work, the congestion is significantly reduced (from 20% to 75% depending
on the matrix of traffic considered), and the fairness, when evaluated in terms of the Jain index, is generally higher than
0.94. Moreover, the algorithm brings advantages when employed in dynamic scenarios where the logical topology is frequently
reconfigured, as it is fast and, in contrast to other algorithms previously proposed, the calculation process can be stopped
at any time (if required) in order to give the best virtual topology found up to the moment.
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Ramón J. DuránEmail: |
4.
Ramón J. Durán Ignacio de Miguel Noemí Merayo Patricia Fernández Rubén M. Lorenzo Evaristo J. Abril 《Photonic Network Communications》2009,18(3):334-344
A new multipurpose genetic algorithm, based on Pareto optimality, is proposed to design logical topologies for wavelength-routed
optical networks with the aim of minimizing both the congestion and the end-to-end delay. Simulation results show its efficiency
when compared with other previously proposed algorithms, achieving in most cases optimal or near-optimal solutions, and in
less time than other methods. Moreover, since the algorithm relies on Pareto optimality, not only does it obtain a single
logical topology but a set of them, so that the network designer can easily select the most appropriate one according to the
current network requirements. 相似文献
5.
The use of azo dyes in industrial activities generates a large volume of contaminated wastewater; these pollutants in water bodies affect aquatic biota and human health. A functional biocomposite sorbent material was synthesized using cross-linked chitosan with oxalic acid that forms a coating on alumina ceramic particles (AOCh). The removal of Reactive Red 195, a reactive azo dye, using a fixed-bed adsorption column filled with this material was tested. AOCh was physico-chemically characterized by Fourier transform infrared spectroscopy–total attenuated reflection (FTIR-ATR), scanning electron microscopy–energy dispersion spectrometry X-ray (SEM-EDS), X-ray diffraction (XDR), thermo-gravimetric analysis (TGA), and Z-potential. The dynamic adsorption performance was analyzed from experimental breakthrough curves obtained in fixed-bed columns by modifying different operating conditions (bed depth, volumetric flow rate, and dye inlet concentration). Equilibrium adsorption isotherms were determined under dynamic conditions and compared with batch results. The maximum adsorption capacity of the dynamic equilibrium isotherm obtained from the continuous assays was 331 mg/g; this value was the highest in comparison to other tested materials reported in the literature. Different dynamic adsorption models were applied to fit experimental data, including Thomas, Bohart–Admas, Yoon–Nelson, logistic general model, bed depth surface time (BDST), and modified dose response (Yan) models. A critical analysis of these equations was presented, showing the equivalences and the relationship among the coefficients. The Yan model achieved the highest level of agreement between the experimental and predicted values of the breakthrough curves. The use of this model enables scaling-up the industrial process for dye removal. The present work proposed a novel biosorbent material and contributes to the analysis of industrial dye removal under dynamic conditions. 相似文献
6.
Lorenzo JM Purriños L Bermudez R Cobas N Figueiredo M García Fontán MC 《Meat science》2011,89(1):105-109
The polycyclic aromatic hydrocarbon (PAH) content in two traditional smoked sausages from Spain was determined. Results showed, that total average levels of PAHs found were higher in "Chorizo de cebolla" (101.81 vs. 98.48 μgkg(-1)). Most contents of PAHs found in both sausages were phenanthrene, naphthalene and anthracene. The maximum level for benzo[a]pyrene (BaP) of 5 μgkg(-1) in smoked meat products was not exceeded in any samples. BaP represented a 0.73% and 1.15% with respect to the total sum of the 15 PAHs that were investigated in this study for "Chorizo gallego" and "Chorizo de cebolla", respectively. Correlation statistic analysis (P < 0.01) of the contents from samples analysed, showed that BaP was a good marker for Σ15 PAHs in "Chorizo gallego" samples (R(BaP/Σ15PAHs) = 0.77; P < 0.01) and it was a good marker for 7 U.S. EPA probably carcinogenic PAHs in "Chorizo de cebolla" samples (R(BaP/7EPA) = 0.95) and in "Chorizo gallego" samples (R(BaP/7EPA) = 0.81). 相似文献
7.
De la Torre C Illa I Faulkner G Soria L Robles-Cedeño R Dominguez-Perles R De Luna N Gallardo E 《Proteomics. Clinical applications》2009,3(4):486-497
The muscular dystrophies are a large and heterogeneous group of neuromuscular disorders that can be classified according to the mode of inheritance, the clinical phenotype and the molecular defect. To better understand the pathological mechanisms of dysferlin myopathy we compared the protein-expression pattern in the muscle biopsies of six patients with this disease with six patients with limb girdle muscular dystrophy 2A, five with facioscapulohumeral dystrophy and six normal control subjects. To investigate differences in the expression levels of skeletal muscle proteins we used 2-DE and MS. Western blot or immunohistochemistry confirmed relevant results. The study showed specific increase expression of proteins involved in fast-to-slow fiber type conversion (ankyrin repeat protein 2), type I predominance (phosphorylated forms of slow troponin T), sarcomere stabilization (actinin-associated LIM protein), protein ubiquitination (TRIM 72) and skeletal muscle differentiation (Rho-GDP-dissociation inhibitor ly-GDI) in dysferlin myopathy. As anticipated, we also found differential expression of proteins common to all the muscular dystrophies studied. This comparative proteomic analysis suggests that in dysferlin myopathy (i) the type I fiber predominance is an active process of fiber type conversion rather than a selective loss of type II fibers and (ii) the dysregulation of proteins involved in muscle differentiation further confirms the role of dysferlin in this process. 相似文献
8.
de-Los-Santos-Alvarez N de-Los-Santos-Alvarez P Lobo-Castañón MJ Miranda-Ordieres AJ Tuñón-Blanco P 《Analytical chemistry》2005,77(13):4286-4289
The generation of a new electrocatalytic system for NADH after oxidizing flavin adenine dinucleotide (FAD) is shown. The oxidation is performed in alkaline medium until +1.4 V (Ag/AgCl) at graphite electrodes. The catalytic activity is ascribed to the electrooxidized moiety of FAD and not to quinone surface groups. A comparison between this catalyst and that attributed to poly(FAD) (Karyakin, A. A.; Ivanova Y. N.; Revunova, K. V.; Karyakina, E. E. Anal. Chem. 2004, 76, 2004-2009.) is presented. It is concluded that the surface quinone groups generated during the strong anodization of the electrode in acidic medium at 2-2.5 V and not the poly(FAD) are responsible for the catalytic activity described in the above mentioned work. 相似文献
9.
10.
Effect of Butternut (Cucurbita moschata Duchesne ex Poiret) Fibres on Bread Making, Quality and Staling 总被引:1,自引:0,他引:1
Marina de Escalada Pla Ana María Rojas Lía Noemí Gerschenson 《Food and Bioprocess Technology》2013,6(3):828-838
The effect of different enriched fibre products obtained from butternut (Cucurbita moschata Duchesne ex Poiret) on bread making and bread quality was evaluated through the study of bread yield, quality parameters (specific volume, crumb firmness, crumb and crust colour) and bread shelf life. Fractions tested were obtained from butternut mesocarp through ethanolic treatment (fraction AIR) or through dehydration (fraction S) or from the ethanolic treatment of peel (fraction C). These fractions were incorporated in a bread formula, at levels of 5, 10 and 15 g of fibre fraction per kilogram of wheat flour. The study of crumb through digital imaging and thermal analysis was also performed in order to better understand the effects observed. An important influence of water absorption kinetics and chemical composition of the fibre fractions studied was observed in the results obtained. Lower bread firmness was determined 24 h after baking when 10 g of C or either 10 or 15 g of S was present per kilogram of wheat flour used. Breads made with flour containing 10–15 g of S or 5 g of C per kilogram of wheat flour tended to be softer, while 10 g of C per kilogram of flour produced significantly softer breads along 9 days storage. 相似文献