558 research outputs found

    PEF treatments of high specific energy permit the reduction of maceration time during vinification of Caladoc and Grenache grapes

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    Phenolic compounds extracted from the solid parts of the grapes during the maceration-fermentation stage define many of the sensory attributes of red wine such as color, bitterness or astringency. The effect of moderate a PEF treatment (M-PEF) (5 kV·cm-1, 8.8 kJ·kg-1) and an intense PEF treatment (I-PEF) (5 kV·cm-1, 52.9 kJ·kg-1) on the reduction of maceration time during vinification of Caladoc and Grenache grapes was investigated. In both grape varieties, M-PEF treatment combined with 4 days of maceration was the most effective treatment in achieving high anthocyanin content, color intensity and total phenol index at the end of fermentation. The I-PEF treatment promoted a rapid release of anthocyanins and phenolic compounds, along with a fast increment in the color intensity of the must after 24 h of maceration. Although the color intensity and anthocyanin content decreased significantly throughout fermentation when grape pomace was removed after 24 h, these parameters were similar, after 3 months of bottling, in the case of Caladoc and slightly lower in Grenache than the control wine, for which maceration was extended for 10 days. Therefore, results obtained in this investigation are the first to demonstrate the potential of I-PEF for the reduction of maceration time to 24 h in red winemaking

    Pulsed Electric Fields (PEF) applications in the inactivation of parasites in food

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    Background Parasites are concerning food-borne pathogens. Some of them are currently not being routinely controlled in food, probably because their burden on public health is underestimated and the relative importance of different transmission routes is not completely known. Parasitic incidences could be avoided if preventive technologies were applied during food processing. Effective inactivation treatments are currently based on heat or freezing, but their side effects collide head-on with current consumer trends and new culinary habits. Scope and approach This review describes the potential application of Pulsed Electric Field (PEF) technology in the control of food-borne parasites, with the aim of reducing the viability and infectivity of parasite transmission stages without affecting food quality. Results of published studies performed on different media are critically analyzed and factors affecting the outcomes are examined. Key findings and conclusions Recent studies on the topic demonstrate the feasibility of PEF as an alternative to traditional freezing processes for the inactivation of Anisakis in fish. The development of new PEF equipment is advancing at a rapid pace, allowing for food treatment at a scale that would have been unimaginable some years ago. A review of more basic-science studies carried out on buffer media would contribute to progress in addressing the underlying drawbacks that remain to be solved. Thoroughly different fields (parasitology, physics, food engineering, water sanitation, etc.) should converge to achieve the industrial implementation of PEF for the inactivation of food-borne parasites

    Greenhouse effect gases emission implications on sustainability of the Campus of Vegazana, University of León

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    En este trabajo se presentan los resultados del estudio de emisiones de CO2, uno de los gases más importantes de efecto invernadero, debido a la actividad desarrollada en el Campus de Vegazana de la Universidad de León, para el año 2006. El estudio se enmarca en un proyecto más amplio de cálculo del indicador Huella Ecológica (HE), desarrollado para conocer en qué medida se alcanzan los objetivos de sostenibilidad establecidos para el Campus, así como para el desarrollo de propuestas encaminadas a la reducción de las emisiones de CO2. Los resultados obtenidos reflejan como el área de superficie biológicamente productiva necesaria para absorber las emisiones del Campus constituyen cerca del 99% del área total de HE. La mayor parte de estas emisiones proceden del gasto energético para electricidad (38%) y uso térmico (24%, seguido del transporte (19%) y la construcción del propio complejo universitario (16%, el cual hace referencia únicamente al año 2006, considerando una vida útil de 27 años para los edificios e instalaciones del Campus, inaugurado en 1979. Una vez analizadas cualitativa y cuantitativamente las emisiones producidas, se ha buscado conocer el total de superficie forestal necesaria para absorber dichas emisiones, considerando los datos del Tercer Inventario Forestal Nacional (2003) sobre cobertura de las masas forestales para el territorio nacional, y los aportados por Bravo (2007) en relación a las tasas de fijación del gas por parte de éstas. Como conclusión, puede estimarse que del total de la superficie forestal de la provincia de León, un 0.46% es necesaria como depósito y sumidero del CO2 emitido por el Campus de Vegazana (8.470.168 toneladas. Esta estimación se ha realizado considerando que las masas forestales son las únicas depositarias de CO2, tarea compartida en la naturaleza, no obstante, con el suelo, el agua y los cultivosIn this work, we present the results obtained about the CO2 emissions, one of the most important greenhouse gases, due to the normal activity developed in the Campus of Vegazana of the University of León for the year 2006. This study is all part of a wider project for evaluating the Fingerprint ecological indicator (HE, initially developed for assessing if the sustainability objectives established by the University policies for the Campus of Vegazana have been achieved, as well as the development of proposals and ideas directed towards the reduction of the emissions of CO2. Results obtained showed that the biologically productive area necessary for absorbing all emissions are close to the 99% of the total value of HE. The majority of these emissions come from the energy consumed for producing electricity (38%) and heating (24%), followed by the transport (19%) and the constructions of the buildings and infrastructures of the University (16%, which related just for the year 2006, considering a living period of 27 years as it was inaugurated in 1979. Once analyzed qualitatively and quantitatively the emissions produced, it was developed a method for estimating the total area covered necessary for absorbing them by considering data available from the Third National Forestry Inventory of Spain (2003), related with the forest cover of the territory, and data provided by Bravo(2007, about the absorption rate of the tree species. As a conclusion, we estimated that form the total area covered by forests of the Province of León, a 0.46% is necessary as sink of the CO2 produced in the Campus of Vegazana (8.470.168 ton. This assessment has been achieved considering that forests are the only warehouse of CO2, when actually soil, water and crops are in nature.Peer Reviewe

    Novel electronic device to quantify the cyclic fatigue resistance of endodontic reciprocating files after using and sterilization

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    Background: The aim of this study was to analyze the effects of the time of use (TU) and sterilization cycles (SC) of endodontic reciprocating files on cyclic fatigue resistance. Methods: One-hundred-and-twenty (120) Procodile NiTi endodontic reciprocating instruments were selected at random and distributed into the following study groups: A: 0 sterilization cycles/0s time of use (n = 10); B: 0/60 (n = 10); C: 0/120 (n = 10); D: 1/0 (n = 10); E: 1/60 (n = 10); F: 1/120 (n = 10); G: 5/0 (n = 10); H: 5/60 (n = 10); I: 5/120 (n = 10); J: 10/0 (n = 10); K: 10/60 (n = 10); and L: 10/120 (n = 10). A dynamic cyclic fatigue device was designed using computer-aided design/computer-aided engineering (CAD/CAE) technology and created with a 3D printer to simulate the pecking motion performed by the clinician. Failure of the endodontic rotary instrument was detected by a light-emitting diode-light-dependent resistor (LED-LDR) system controlled by an Arduino driver complex and management software. The results were analyzed using the ANOVA test. Results: All pairwise comparisons presented statistically significant differences between the time to failure, number of cycles to failure and number of cycles of in-and-out movement for the time of use study groups (p 0.05). Conclusions: The time of use of NiTi endodontic reciprocating files negatively affects dynamic cyclic fatigue resistance. Dynamic cyclic resistance is not affected by the number of sterilization cycles

    Simulación de la evaporación horaria a partir de datos meteorológicos

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    [ES] En este artículo se proponen y validan dos modelos, con distinto grado de complejidad, para simular la evaporación a escala horaria en pequeños cuerpos de agua, concretamente en tanques evaporímetros clase A. En primer lugar se ha desarrollado un modelo multicapa, basado en la discretización del volumen de agua en varios estratos. Se han establecido las ecuaciones del balance de energía, tanto en la capa superficial como en las sucesivas capas consideradas, y se ha resuelto el sistema de ecuaciones que configuran el balance energético del tanque mediante aproximaciones iterativas. La validación de este modelo a escala horaria, con datos experimentales obtenidos en Cartagena (España), confirma la existencia de un proceso de mezcla convectivo en el tanque, que produce una homogeneización de la temperatura del agua incluso durante el periodo diurno. Para modelizar correctamente este fenómeno se ha propuesto y validado una función del viento que actúa sobre el coeficiente de mezcla convectivo en el seno del tanque. En una segunda etapa, se ha desarrollado un modelo numérico simplificado que asume un funcionamiento isotermo del tanque. Los resultados obtenidos son similares a los proporcionados por el modelo multicapa, aunque algo menos precisos.Este trabajo ha sido financiado por la Fundación Séneca mediante el proyecto PI-45/00851/FS/01 “Desarrollo y evaluación experimental de un modelo de evaporación de agua en lámina libre. Aplicación a la mejora del aprovechamiento del agua mediante el estudio de la eficiencia de técnicas reductoras de la evaporación en embalses de riego”.Martínez Álvarez, V.; Molina Martínez, J.; González-Real, MM.; Baille, A. (2005). Simulación de la evaporación horaria a partir de datos meteorológicos. Ingeniería del agua. 12(1):39-51. https://doi.org/10.4995/ia.2005.2550OJS3951121Allen R.G., Pereira L.S., Raes D. y Smith M., 1998. Crop evapotranspiration. guidelines for computing crop water requirements. Irrigation and Drainage Paper nº 56, FAO (United Nations), Rome, p. 300.Bloss, G. y Harleman, R.F., 1979. Effect of wind-mixing on the thermocline formation in lakes and reservoirs. Technical Report 249, Ralph M. Parson Laboratory, MIT, Cambridge, MA, p. 68.Brutsaert, W., 1975. On a derivable formula for long-wave radiation from clear skies. Water Resources Research, 11 (5): 742-744.Condie, S.A. y Webster, I.T., 1997. The influence of wind stress, temperature, and humidity gradients on evaporation from reservoirs.Water Resources Research, 33 (12): 2813-2822.Chow, V.T., Maidment, D.R. y Mays, L.W., 1999. Applied Hydrology. Ed. McGraw-Hill, p. 584.Doorembos, J. y Pruitt, W.O., 1977. Crop water requirements. Irrigation and Drainage Paper No. 24, FAO (United Nations), Rome, p. 179.Harleman, D.R.F., 1982. Hidrotermal analisis of lakes and reservoirs. Journal of the Hydrology Division, ASCE, 108: 302-325.Henderson-Sellers, B., 1984. Engineering Limnology. Pitman Advanced Publishing Program, Boston, M.A., p. 356.Jacobs, A.F.G., Heusinkveld, B.G. y Lucassen D.C., 1998. Temperature variation in a class A evaporation pan. Journal of Hydrology, 206: 75 -83.Jacobs, A.F.G., Jetten, Th.H., Lucassen, D.C., Heusinkveld, B.G. y Nieveen, J.P., 1997. Diurnal temperature fluctuations in a natural shallow water body. Agriculture and Forest Meteorology, 88: 269-277.Linsley, R.K.,1958. Techniques for Surveying Water Resources. World Meteorological Organization, Technical Note nº 26, 124 p.Linsley, R.K., Kohler, M.A. y Paulhus, J.L.H., 1992, Evaporation and Transpiration. Hydrology for Engineers. New York, McGrawHill, 508 p.Losordo, T.M. y Piedrahita, R.H., 1991. Modelling temperature variation and termal stratification in shallow aquaculture ponds. Ecological Modelling, 54: 189-226.Miro-Granada, J., 1984. Evaporación en Embalses. Instituto Nacional de Meteorología (INM). Ministerio de Transportes, Turismo y Comunicaciones, Madrid, p.139.Molina, J.M., 2004. Caracterización y modelización de la evaporación en tanques evaporímetros y embalses de riego. Evaluación de los efectos de mallas de sombreo. Tesis Doctoral, Departamento de Ingeniería de Alimentos y del Equipamiento Agrícola, Universidad Politécnica de Cartagena, España, p 207.Molina, J.M., Martínez, V. y Górriz, B., 2003. Automatización con control horario del llenado de tanques evaporímetros clase A. 2º Congreso Nacional de Agroingeniería, Córdoba, España, 451-452.Molina, J.M., Martínez, V. y Baille, A., 2002a. Estación experimental para el registro de las variables implicadas en la modelización del proceso de evaporación y el estudio de diferentes técnicas reductoras. 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    Bayesian Analysis of the Association between Casein Complex Haplotype Variants and Milk Yield, Composition, and Curve Shape Parameters in Murciano-Granadina Goats

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    Considering casein haplotype variants rather than SNPs may maximize the understanding of heritable mechanisms and their implication on the expression of functional traits related to milk production. Effects of casein complex haplotypes on milk yield, milk composition, and curve shape parameters were used using a Bayesian inference for ANOVA. We identified 48 single nucleotide polymorphisms (SNPs) present in the casein complex of 159 unrelated individuals of diverse ancestry, which were organized into 86 haplotypes. The Ali and Schaeffer model was chosen as the best fitting model for milk yield (Kg), protein, fat, dry matter, and lactose (%), while parabolic yield-density was chosen as the best fitting model for somatic cells count (SCC × 103 sc/mL). Peak and persistence for all traits were computed respectively. Statistically significant differences (p < 0.05) were found for milk yield and components. However, no significant difference was found for any curve shape parameter except for protein percentage peak. Those haplotypes for which higher milk yields were reported were the ones that had higher percentages for protein, fat, dry matter, and lactose, while the opposite trend was described by somatic cells counts. Conclusively, casein complex haplotypes can be considered in selection strategies for economically important traits in dairy goats

    Software-Automatized Individual Lactation Model Fitting, Peak and Persistence and Bayesian Criteria Comparison for Milk Yield Genetic Studies in Murciano-Granadina Goats

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    SPSS model syntax was defined and used to evaluate the individual performance of 49 linear and non-linear models to fit the lactation curve of 159 Murciano-Granadina goats selected for genotyping analyses. Lactation curve shape, peak and persistence were evaluated for each model using 3107 milk yield controls with an average of 3.78 ± 2.05 lactations per goat. Best fit (Adjusted R2) values (0.47) were reached by the five-parameter logarithmic model of Ali and Schaeffer. Three main possibilities were detected: non-fitting (did not converge), standard (Adjusted R2 over 75%) and atypical curves (Adjusted R2 below 75%). All the goats fitted for 38 models. The ability to fit different possible functional forms for each goat, which progressively increased with the number of parameters comprised in each model, translated into a higher sensitivity to explaining curve shape individual variability. However, for models for which all goats fitted, only moderate increases in explanatory and predictive potential (AIC, AICc or BIC) were found. The Ali and Schaeffer model reported the best fitting results to study the genetic variability behind goat milk yield and perhaps enhance the evaluation of curve parameters as trustable future selection criteria to face the future challenges offered by the goat dairy industry

    Goat Milk Nutritional Quality Software-Automatized Individual Curve Model Fitting, Shape Parameters Calculation and Bayesian Flexibility Criteria Comparison

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    SPSS syntax was described to evaluate the individual performance of 49 linear and non-linear models to fit the milk component evolution curve of 159 Murciano-Granadina does selected for genotyping analyses. Peak and persistence for protein, fat, dry matter, lactose, and somatic cell counts were evaluated using 3107 controls (3.91 ± 2.01 average lactations/goat). Best-fit (adjusted R2) values (0.548, 0.374, 0.429, and 0.624 for protein, fat, dry matter, and lactose content, respectively) were reached by the five-parameter logarithmic model of Ali and Schaeffer (ALISCH), and for the three-parameter model of parabolic yield-density (PARYLDENS) for somatic cell counts (0.481). Cross-validation was performed using the Minimum Mean-Square Error (MMSE). Model comparison was performed using Residual Sum of Squares (RSS), Mean-Squared Prediction Error (MSPE), adjusted R2 and its standard deviation (SD), Akaike (AIC), corrected Akaike (AICc), and Bayesian information criteria (BIC). The adjusted R2 SD across individuals was around 0.2 for all models. Thirty-nine models successfully fitted the individual lactation curve for all components. Parametric and computational complexity promote variability-capturing properties, while model flexibility does not significantly (p > 0.05) improve the predictive and explanatory potential. Conclusively, ALISCH and PARYLDENS can be used to study goat milk composition genetic variability as trustable evaluation models to face future challenges of the goat dairy industry

    Does the Acknowledgement of αS1-Casein Genotype Affect the Estimation of Genetic Parameters and Prediction of Breeding Values for Milk Yield and Composition Quality-Related Traits in Murciano-Granadina?

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    A total of 2090 lactation records for 710 Murciano-Granadina goats were collected during the years 2005–2016 and analyzed to investigate the influence of the αS1-CN genotype on milk yield and components (protein, fat, and dry matter). Goats were genetically evaluated, including and excluding the αS1-CN genotype, in order to assess its repercussion on the efficiency of breeding models. Despite no significant differences being found for milk yield, fat and dry matter heritabilities, protein production heritability considerably increased after aS1-CN genotype was included in the breeding model (+0.23). Standard errors suggest that the consideration of genotype may improve the model’s efficiency, translating into more accurate genetic parameters and breeding values (PBV). Genetic correlations ranged from −0.15 to −0.01 between protein/dry matter and milk yield/protein and fat content, while phenotypic correlations were −0.02 for milk/protein and −0.01 for milk/fat or protein content. For males, the broadest range for reliability (RAP) (0.45–0.71) was similar to that of females (0.37–0.86) when the genotype was included. PBV ranges broadened while the maximum remained similar (0.61–0.77) for males and females (0.62–0.81) when the genotype was excluded, respectively. Including the αS1-CN genotype can increase production efficiency, milk profitability, milk yield, fat, protein and dry matter contents in Murciano-Granadina dairy breeding programs
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