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91.
Antonio Bevilacqua Mariangela Gallo Maria Rosaria Corbo Milena Sinigaglia 《International Journal of Food Science & Technology》2013,48(7):1366-1370
The main goal of this research was the evaluation of the survival of Enterobacter cloacae in a model olive brine. Two different assays were run; the first experiment assessed the viability of the target in brines containing NaCl (6–12%) and p‐coumaric acid (0.0–0.05%), adjusted to different pHs (4–10) and stored at 10–30 °C for 9 days. The death rate and cell levels at selected times were modelled with a polynomial equation to highlight the individual and interactive effects of NaCl/p‐coumaric acid/pH/temperature. Then, a second experiment was run for 3 months (temperature, 10 °C; pH, 4.5–5.5; NaCl, 6–8%). The survival of E. cloacae was affected mainly by pH, then by salt and temperature; however, the significance of the variables changed within the time, as salt and temperature acted in a significant way only after 1 day. 相似文献
92.
Antonio Bevilacqua Maria Rosaria Corbo Giuseppe Martino Milena Sinigaglia 《International Journal of Food Science & Technology》2013,48(8):1618-1625
This article proposes an approach to determine the level of Pseudomonas spp. in milk, based on the evaluation of the content of oxygen and carbon dioxide produced in the headspace of sealed vials; the research was divided into two phases: model building and preliminary validation. Three different strains of Pseudomonas spp., Ps. putida (wild strain) and Ps. fluorescens (wild and collection isolates), were used as targets. Data of CO2 and O2 were modelled through a modified positive (CO2) or a negative Gompertz equation (O2) to estimate the Minimum Detection Time (MDT), defined as the time to attain 3% of CO2 (MDT1) or a decrease in the content of O2 by 3% (MDT2). Then, MDT1 and MDT2 were submitted to a linear regression procedure, using cell concentration as independent variable; the correlations ‘MDT1/cell concentration’ and ‘MDT2/cell concentration’ showed high determination coefficients (>0.983). Moreover, the regression procedure pointed out that both MDT1 and MDT2 decreased by ca. 3 h for an increase in cell count of 1 log cfu mL?1. Preliminary validation in milk pointed out that the error associated with the regression line ‘MDT2/cell concentration’ was below 5%. 相似文献
93.
Milena Lambri Roberta Dordoni Angela Silva Dante M. De Faveri 《International Journal of Food Science & Technology》2012,47(1):1-12
The impact of bentonite fining is generally studied on final wines, and few studies have evaluated it throughout the winemaking process. This work studied the fate of proteins and terpenols, the main targets of bentonite addition, during the processing of Chambave Muscat aromatic grapes. The experimental trials were performed in two vintages (2006 and 2007) and included the following processes: bentonite addition to must only (100 g hL?1 in both vintages), fining of wine only (100 g hL?1 in both vintages), double bentonite treatment on must and wine (200 and 150 g hL?1 in 2006 and in 2007, respectively) and no treatment (control). The results demonstrated that the treatment allowing the best removal of protein was the addition of bentonite to must only. Moreover, a lower removal of free terpenols was observed in samples from double treatment compared with wines fined with bentonite only after alcoholic fermentation. 相似文献
94.
Ana Miklavčič Vekoslava Stibilj Ester Heath Tomaž Polak Janja Snoj Tratnik Janez Klavž Darja Mazej Milena Horvat 《Food chemistry》2011
In order to contribute to the general understanding of the risks and benefits of consuming fish and fish products, total mercury (THg), monomethylmercury (MeHg), polychlorinated biphenyls (PCBs), selenium (Se), n-3 and n-6 fatty acids were determined in fresh and canned fish on the Slovenian market. Furthermore, the mercury exposure of pregnant women in Slovenia was assessed by determining total mercury (THg) in hair, and through fresh and canned fish consumption obtained by a food frequency questionnaire. Based on the frequency of fish consumption and levels of MeHg, THg and PCBs determined in the present study, it can be concluded that fish available on the Slovenian market do not represent a health risk. It was also confirmed that fish are important sources of selenium and n-3 fatty acids. 相似文献
95.
96.
Naydu Shirley Rojas-Higuera Ana Milena Pava-Sánchez Diana Lizeth Pinzón Rangel Lucía Ana Díaz-Ariza Balkys Quevedo-Hidalgo Aura Marina Pedroza-Rodríguez 《Holz als Roh- und Werkstoff》2017,75(2):263-273
This study assessed the bio-transformation of sawdust wood waste by a white rot fungi consortium and explores the use of the final product as a carrier for plant growth-promoting bacteria. During 75 days, Tabebuia roseae and Eucalyptus pellita (1:1) sawdust wood were used as growing substrates for Ganoderma lucidum, Pleurotus ostreatus, Trametes versicolor and Phanerochaete chrysosporium. Then, bio-transformed sawdust was evaluated as carrier of two strains of Enterobacter sp. and one strain of Stenotrophomonas maltophilia. Biologic activity and viability were determined at two storage temperatures (23–4 °C) for 60 days. Sawdust mixture was bio-transformed by white rot fungi. After 45 days, the carbon/nitrogen ratio was reduced up to 46 %, and 4.8 mg/g of CO2 of residue was produced. Enzymatic activities attained a peak of 36.7 and 0.8 U g?1 for laccase and manganese peroxidase, respectively in 45 days. Population of plant growth-promoting bacteria immobilized in bio-transformed sawdust wood decreased to 105 CFU g?1. However, this concentration and its biologic activity remained stable at 23 °C. 相似文献
97.
Milena Vega Montaña Elviro Ramón Cerro Miguel Ángel Galán 《Chemical Engineering Communications》2017,204(7):750-760
Rigid adsorbents used as matrix skeleton have advantages over soft gel media for downstream processing of proteins. The adsorption of bovine serum albumin (BSA) has been investigated on a rigid ceramic monolith coated with cross-linked microporous agarose (D5). The physical properties of the adsorbent and the adsorption equilibria, adsorption kinetics, and mass transfer behavior have been studied for five different flow rates, with a pH value ranging from pH 4.5 to 7.0. The optimal working flow rate was 14.0?cm3/min, and using this flow rate, increasing the pH does not generate a significant improvement in the adsorption capacity. The rates of BSA adsorption have been measured and it was possible to describe a theoretical model, in which the mass transfer involves a dispersion coefficient (kdisp), which describes the mass transfer in the adsorbent surface, from the volume of the protein solution to the agarose surface. This parameter presents an exponential tendency by increasing the flow rate from 2.37?×?10?6 to 87.40?×?10?6?cm/s for n?=?1. Values obtained for the adsorption kinetic constant (kads) followed the trend of the mass transfer parameter, increasing with the flow rate from 1.94?×?104 to 117.39?×?104?cm2/mol?s. The theoretical model predicts the protein concentration in equilibrium for successive column reuses and it can be readily used to determine the optimal reuse of column. Likewise, for a maximum flow rate of 14?cm3/min, pressure drop was 0.04?MPa, being an advantage in front of packed columns that have higher pressure drop. 相似文献
98.
Laura Milena Pinzón Francisco Javier Cedano Camila Irene Castro Juan Carlos Briceño Juan Pablo Casas Diana Marcela Tabima 《国际聚合物材料杂志》2017,66(14):697-707
The effects of the addition of calcium carbonate (CC) and hydroxyapatite (HA) in chitosan-based biocomposites were studied keeping in mind their potential use as bone adhesives. The formation of coordination bonds between calcium ions and chitosan amino groups was evident, producing ionic cross-links between chitosan macromolecules, which changed chitosan gelation mechanisms, gel strengths, and adhesiveness into bone surfaces; CC concentration is a key factor in these phenomena. A formulation with 2% chitosan and 4% of both CC and HA showed the most promising performance having high levels of adhesion to bone surfaces (0.27?MPa) and a cohesive mode of failure. 相似文献
99.
The correlation between the fiber structure and mechanical properties of two different poly(ethylene terephthalate) fiber types, that is, wool and cotton types produced by three producers, was studied. Fiber structure was determined using different analytical methods. Significant differences in the suprastructure of both types of conventional textile fibers were observed, although some slight variations in the structure existed between those fibers of the same type provided by different producers. A better‐developed crystalline structure composed of bigger, more perfect, and more axially oriented crystallites was characterized for the cotton types of PET fibers. Crystallinity is higher, long periods are longer, and amorphous domains inside the long period cover bigger parts in this fiber type in comparison with the wool types of fibers. In addition, amorphous and average molecular orientation is higher. The better mechanical properties of cotton PET fiber types, as demonstrated by a higher breaking tenacity and modulus accompanied by a lower breaking elongation, are due to the observed structural characteristics. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3383–3389, 2003 相似文献
100.
Veljko?PotkonjakEmail author Spyros?Tzafestas Miomir?Vukobratovic Milena?Milojevic Milos?Jovanovic 《Journal of Intelligent and Robotic Systems》2011,63(2):191-210
It is a well-known fact that the growth of technology has radically changed our approach to biosciences and medicine. What
is interesting is that in the last decade we have witnessed a reverse influence—a trend towards “biologically inspired” solutions
to technical problems. This leads to a true symbiosis between bio and technical sciences. A good example is the intersection
and overlapping of three distinct fields: sports, medicine, and robotics. This paper intends to apply sophisticated methods
developed for mathematical modeling of humanoid robots in real human motions, particularly in posture stabilization and selection
of appropriate postures for different situation in sports and every day life. A general simulation system is realized: following
a deductive principle, the algorithm considers particular human/humanoid motions (like those occurring in different sports)
as being just special cases of a general motion and impact theory. Simulation includes the interaction with the environment.
Simulating a human/humanoid dynamics in a given task, all relevant characteristics could be found: trajectories, velocities
and accelerations, loads of joints, power requirements, energy consumption, contact forces including ground reactions, impact
effects, etc. Simulation is used in solving a problem that is important for both humans and humanoid robots, namely, the behavior
of a posture (keeping stability or collapsing) when subject to different disturbances. Although “posture” is mainly a static
term, maintaining its balance in the presence of disturbances is a truly dynamic problem. Typical postures from every day
life and sports are considered, such as: upright standing, squat (and partial squat), and three karate postures. Two sorts
of disturbances are applied to eventually, compromise the posture: external impulse and permanent external force. This paper
does not aim to suggest some new control strategy but to develop the dynamic model and simulation algorithm, and apply them
to compare the robustness of different postures to external disturbances. 相似文献