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51.
Changes of the cell surface hydrophobicity of Lactobacillus acidophilus La‐5 in response to pH,temperature and inulin 下载免费PDF全文
Antonio Bevilacqua Leonardo Petruzzi Barbara Speranza Daniela Campaniello Milena Sinigaglia Maria Rosaria Corbo 《International Journal of Food Science & Technology》2018,53(5):1262-1268
The main topic of this study was to study how cell surface hydrophobicity (CSH) could change in response to pH, temperature and inulin; Lactobacillus acidophilus La‐5 was used as a model microorganism. pH, temperature, inulin and incubation time (exposure to prebiotic or incubation at pH 4.0 and 9.0) were combined through a full factorial design and a Central Composite Design; the results were analysed using a multifactorial anova (first step) and a stepwise regression (second step). Temperature and pH significantly affected CSH: an increase in the temperature determined a significant increase in CSH, whereas the correlation pH vs. CSH was negative, as an increase in pH caused a significant decrease in CSH. Inulin played a significant role, but its effect could be influenced by temperature, pH and exposure time. This study is the first approach on the effects of some environmental factors on CSH and suggests that the culturing conditions and/or the exposure to some prebiotics could modify it with positive or negative effects. 相似文献
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Anna Rita Bavaro Mariaelena Di Biase Amalia Conte Stella Lisa Lonigro Leonardo Caputo Annamaria Cedola Matteo Alessandro Del Nobile Antonio Francesco Logrieco Paola Lavermicocca Francesca Valerio 《International Journal of Food Science & Technology》2021,56(7):3197-3208
Production of the traditional Italian Focaccia bread (FcBread) requires reformulation to meet the new rules for healthier foods. We tested the applicability of a short-fermented (15 h) liquid sourdough (LS) (dough yield, DY, 250), obtained using quinoa (Q) or amaranth (Am) flour fermented with a Weissella cibaria strain (C43-11) producing exopolysaccharides (EPS) as fat replacer in yeast-leavened FcBread. The LSs were applied during the FcBread-making process at industrial pilot plant, reducing the added fat amount by 20% (FcBread-QLS and FcBread-AmLS) and products were compared with reference samples not containing EPS. All the products were analysed for physico-chemical properties (pH, TTA, organic acids, protein content and profile, instrumental colour), textural properties, sensory quality and glycemic index. The application of both pseudo-cereal-based W. cibaria LSs in FcBread allowed obtaining products with a reduced amount of fat, increased protein amount, mainly due to the albumin and glutenin/glutelin fractions, reduced glycemic index, improved texture and preserved in the traditional sensory profile of ‘focaccia’. 相似文献
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Leonardo Crauss Daronco Valter Roesler José Valdeni de Lima Ricardo Balbinot 《Multimedia Tools and Applications》2012,61(3):571-597
This paper presents a study of quality on scalable video sequences coded using the scalable extension of the H.264 standard (SVC). A group of experiments was performed to measure, primarily, the effects that transmission instability has in the quality of the videos and the relationship among three scalability methods (spatial, temporal and quality) in terms of quality. A set of experiments was performed to measure the subjective quality using the ACR-HRR methodology and recommendations from ITU-R Rec. BT.500 and ITU-T Rec. P.910. The results show that the amount of instability is not as important as just the presence of instability, that video quality can be deteriorated due to instability and that temporal scalability usually produces videos with worse quality than spatial and quality scalabilities. 相似文献
55.
Sara Silva Stephen Dignum Leonardo Vanneschi 《Genetic Programming and Evolvable Machines》2012,13(2):197-238
Bloat can be defined as an excess of code growth without a corresponding improvement in fitness. This problem has been one
of the most intensively studied subjects since the beginnings of Genetic Programming. This paper begins by briefly reviewing
the theories explaining bloat, and presenting a comprehensive survey and taxonomy of many of the bloat control methods published
in the literature through the years. Particular attention is then given to the new Crossover Bias theory and the bloat control
method it inspired, Operator Equalisation (OpEq). Two implementations of OpEq are described in detail. The results presented
clearly show that Genetic Programming using OpEq is essentially bloat free. We discuss the advantages and shortcomings of
each different implementation, and the unexpected effect of OpEq on overfitting. We observe the evolutionary dynamics of OpEq
and address its potential to be extended and integrated into different elements of the evolutionary process. 相似文献
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María J. Aguirre Mauricio Isaacs Betty Matsuhiro Leonora Mendoza Leonardo S. Santos Simonet Torres 《Food chemistry》2011
Anthocyanins in aged Cabernet Sauvignon red wines were studied by HPLC–MS. The major anthocyanin in 6, 7, and 8 year old red wine extracts was the dimer vitisin A produced by condensation of malvidin-3-O-glucoside mediated by pyruvic acid. In aged wine, the content of malvidin-3-O-glucoside decreased with age with a concomitant increase of vitisin A. The latter is accompanied by several condensation products with molecular weight up to 1500 m/z. Differential pulse voltammetry indicated that aged wines have lower antioxidant capacity than young wine (400 mV), but higher than malvidin-3-O-glucoside (483 mV). Tafel’s plots showed that the electrochemical process occurring in aged wines is different from young wines. Six, seven and eight year old wines show similar behaviour with plots of 234, 177 and 188 mV/dec, respectively. These values are higher than the expected 120 mV/dec corresponding to a first electronic transfer but smaller compared to the 523 mV/dec corresponding to young wine. 相似文献
58.
Edgar Leonardo Romero Marius Strum Wang Jiang Chau 《Journal of Electronic Testing》2013,29(2):223-236
The constant pressure for making functional verification more agile has led to the conception of coverage driven verification (CDV) techniques. CDV has been implemented in verification testbenches using supervised learning techniques to model the relationship between coverage events and stimuli generation, providing a feedback between them. One commonly used technique is the classification- or decision-tree data mining, which has shown to be appropriate due to the easy modeling. Learning techniques are applied in two steps: training and application. Training is made on one or more sets of examples, which relate datasets to pre-determined classes. Precision of results by applying the predictive learning concept has shown to be sensitive to the size of the training set and the amount of imbalance of associated classes, this last meaning the number of datasets associated to each class is very different from each other. This work presents experiments on the manipulation of data mining training sets, by changing the size and reducing the imbalances, in order to check their influence on the CDV efficiency. To do that, a circuit example with a large input space and strong class imbalance was selected from the application domain of multimedia systems and another one, with a small input space that affects the coverage occurrences, was selected from the communication area. 相似文献
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Maurilio Toscano de Lucena Mário Ribeiro de Melo Júnior Mariana Montenegro de Melo Lira Célia Maria Machado Barbosa de Castro Leonardo Aguiar Cavalcanti Mariana Arruda de Menezes Flávia Cristina Morone Pinto José Lamartine de Andrade Aguiar 《Journal of materials science. Materials in medicine》2015,26(2):82
The development of a skin substitute suitable for immediately performing the function of the lost dermis and epidermis could result in a positive impact on the treatment of patients with extensive skin lesions. A biopolymer film was applied to skin wounds to investigate the biocompatibility and cutaneous reaction and to test its activity as a mechanical barrier and conductor in the healing process. Forty Wistar rats of both sexes were used in the present study. Two excisions were performed in the dorsal part of the skin flaps. The polysaccharide film was applied over one of the incisions and other incision was washed with saline. The time spent for complete healing of both lesions was virtually the same in both groups, during 21 days of observation. The film remained attached to the bed of the exposed wound for an average period of 6 days. There were no statistically significant differences with regard to lesion measurement area at assessment times of 2nd, 7th and 14th postoperative days. At day 21, the scar area showed a significant difference (0.0229). After 40 days, all wounds were completely healed. No statistically significant differences were found between the histological parameters assessed in the experimental and control groups. The cellulosic polysaccharide film integrated well with the tissue showing high biocompatibility and low skin reactivity. 相似文献