Characterization and winemaking application of a novel pectin-degrading enzyme complex from Aspergillus sojae ATCC 20235

A novel pectin-degrading enzyme complex produced by Aspergillus sojae ATCC 20235 (PC-AS) using lowcost substrates was characterised in terms of its enzyme activities relevant in winemaking. This novel PC-AS was applied at the maceration/fermentation stage during the elaboration of 'Tempranillo' red wines to study its effect on colour development and the phenolic and amino acid wine composition. PC-AS polygalacturonase activity was the major enzyme activity detected and quantified under winemaking conditions (pH 3.5, 20 °C) and proved being stable and active in the presence of sulfur dioxide. Xylanase activity, albeit in lesser amounts, was also present in PC-AS, and neither pectinesterase, which produces methanol, nor β-glucosidase, which is detrimental to wine colour, were detected in PC-AS. This pectin-degrading complex promoted a faster colour extraction since maximum colour intensity of the enzyme treated wines was reached earlier compared to their controls. After 6 months of storage under winery conditions, wines elaborated with PC-AS presented higher concentrations of caffeic acid, coumaric acid and aspartic acid (p ˂ 0.05), suggesting an improved extraction of grape cell components. In conclusion, the application of PCAS yielded results that showed that it can be used in red winemaking to shorten the maceration time needed to reach high CI values and to improve the extraction of some phenolics and other compounds that enhance the quality of the final product.Facultad de Ciencias ExactasCentro de Investigación y Desarrollo en Fermentaciones Industriale

Metabolismo de un tramo en la cuenca baja del río Cesar, departamento del Cesar, en una época de sequía, Colombia

The functionalities of aquatic systems are the result of biological interactions, the physicochemical conditions of water and the terrestrial environment, these relationships are affected by anthropic actions, such as: deforestation, mining, agriculture, solid waste discharges and domestic and industrial liquids, general harmful practices for aquatic ecosystems. This investigation was carried out with the purpose of estimating the variation of the metabolism and physicochemical variables in the lower basin of the Cesar River, during the period of maximum dry season, the trophic state of the lower basin of the aquatic ecosystem was determined by observations in the changes of the O2 consumption and CO2 accumulation, the processes of photosynthesis and respiration were quantified. Two samplings were carried out in four stations, between February-April 2013, equivalent to the dry period. Physicochemical variables in situ and some nutrients were measured. The metabolism protocol was applied, using the Winkler method (clear and dark bottles), with measurements every hour for 24 h (daily curve). The net metabolism was -10732.23 O2/m3-h, the dark one of -10731.41 02/m3-h and the gross primary production of the entire aquatic community of -10736.91 02/m3-h. These results suggest that the variations in the net and dark metabolism, as well as the primary productivity of the community were almost nil. Additionally, the oxygen produced during the day was consumed quickly at night. Our data show that the trophic state of the lower basin of the Cesar River is eutrophic-heterotrophic, the respiration exceeds the production of O2, which generates deficit of the same and a decrease in the quality of this ecosystem, results that are corroborated with the analyzes of the physicochemical variables measured at the site.Los atributos funcionales de los sistemas acuáticos son resultado de interacciones biológicas, las condiciones fisicoquímicas del agua y el ambiente terrestre. Estas relaciones son afectadas por acciones antrópicas, como: la deforestación, la minería, la agricultura, los vertimientos de residuos sólidos y líquidos domésticos e industriales, en general cualquier práctica nociva para los ecosistemas acuáticos. Este trabajo se realizó con el fin de estimar la variación del metabolismo y las variables fisicoquímicas en un tramo bajo del río Cesar durante la época de máximo estiaje. Se determinó el estado trófico de la cuenca baja del ecosistema acuático por observaciones en los cambios del consumo de O2 y acumulación de CO2, y se cuantificaron los procesos de fotosíntesis y respiración. Se realizaron dos muestreos en cuatro estaciones entre febrero y abril de 2013 (periodo seco). Se midieron los variables fisicoquímicos in situ y algunos nutrientes. Se aplicó el protocolo del metabolismo, utilizando el método de Winkler (botellas clara y oscura), con mediciones cada hora durante 24 h (curva diaria). El metabolismo neto fue de 10732,23 O2/m3-h, el oscuro de -10731,41 O2/m3-h y la producción primaria bruta de toda la comunidad acuática de -10736,91 O2/m3-h. Estos resultados sugieren que las variaciones en el metabolismo neto y oscuro, así como la productividad primaria de la comunidad fueron casi nulas. Adicionalmente, el oxígeno producido durante el día fue consumido rápidamente durante la noche. Nuestros datos demuestran que el estado trófico de la cuenca baja del río Cesar es eutrófico-heterotrófico, la respiración excede la producción de O2, lo que genera déficit del mismo y una disminución de la calidad de este ecosistema, estos datos coinciden con los análisis de las variables fisicoquímicas medidas en el sitio

Motion control in free-standing shape-memory actuators

In this work, free-standing shape-memory thermally triggered actuators are developed by laminating 'thiol-epoxy'-based glassy thermoset (GT) and stretched liquid-crystalline network (LCN) films. A sequential curing process was used to obtain GTs with tailored thermomechanical properties and network relaxation dynamics, and also to assemble the final actuator. The actuation extent, rate and time were studied by varying the GT and the heating rate in thermo-actuation with an experimental approach. The results demonstrate that it is possible to tailor the actuation rate and time by designing GT materials with a glass transition temperature close to that of the liquid-crystalline-to-isotropic phase transition of the LCN, thus making it possible to couple the two processes. Such coupling is also possible in rapid heating processes even when the glass transition temperature of the GT is clearly lower than the isotropization temperature of the LCN, depending on the network relaxation dynamics of the GT and the presence of thermal gradients within the actuators. Interestingly, varying the GT network relaxation dynamics does not affect the actuation extent. As predicted by the analytical model developed in our previous work, the modulus of the GT layer is mainly responsible for the actuation extent. Finally, to demonstrate the enhanced control of the actuation, specifically designed actuators were assembled in a three-dimensional actuating device able to make complex motions (including 'S-type' bending). This approach makes it possible to engineer advanced functional materials for application in self-adaptable structures and soft robotics.Postprint (author's final draft

Lesiones premalignas y malignas en cirugía menor de un centro de salud. Las apariencias engañan

ObjetivoDescribir las características de las lesiones malignas y premalignas detectadas en las intervenciones de cirugía menor realizadas en un centro de saludDiseñoEstudio descriptivo retrospectivoParticipantesSe analizaron 682 lesiones correspondientes a todas las lesiones extirpadas remitidas a anatomía patológica, exceptuando los quistes epidérmicos y triquilemales, lipomas, molluscum, verrugas vulgares y uñasEmplazamientoCentro de Salud Rochapea (Pamplona)Mediciones principalesAnalizamos los diagnósticos anatomopatológicos y la distribución por sexos, grupos de edad, localización, técnica y afección de bordes en 27 lesiones displásicas y 11 lesiones malignasResultadosEncontramos una mayor frecuencia de lesiones malignas y premalignas en mujeres, entre 15 y 44 años de edad para las displasias y entre 45 y 64 años para las malignas. La localización más frecuente fue la espalda, y la técnica más empleada la escisión fusiforme. Con esta técnica encontramos el mayor porcentaje de bordes sin lesión en las displasias. Las lesiones que tenían afectados los bordes corresponden a muestras de punch y escisión circular. Ninguna de las lesiones malignas presentaba afección de bordesConclusionesLa mayor parte de las lesions malignas no se sospechan, aparecen en muestras que se remiten con un diagnóstico de benignidad. El empleo de ciertas técnicas como la escisión fusiforme en las lesiones en que existe una potencial malignidad, aunque en principio parezcan benignas, nos permite una extirpación con bordes libresObjectiveTo describe the characteristics of the malignant and pre-malignant lesions found in the minor surgical interventions performed at a health centreDesignRetrospective, descriptive studyParticipants682 lesions: all the lesions extirpated and referred to pathology except for epidermal and trichilemmal cysts, lipomas, molluscum, common warts, and nailsSettingRochapea Health Centre, PamplonaMain measurementsWe analysed the anatomical-pathological results and the distribution by sex, age-group, location, technique and edges affected in 27 dysplasias and 11 malignant lesionsResultsWe found that malignant and premalignant lesions were more common in women, aged 15 to 44 for dysplasias and 45- 64 for malignant lesions. The most common location was on the back; the most frequent technique, fusiform excision. This technique had the highest percentage of edges without lesion in dysplasias. The lesions whose edges were affected corresponded to punch and circular excision samples. None of the malignant lesions had their edges affectedConclusionsMost malignant lesions are not suspected. They appear in samples referred with a diagnosis of benign. Employment of techniques such as fusiform excision in lesions which are potentially malign, even though in principle they seem benign, enables them to be extirpated with free edge

Fitoplancton de la zona litoral del departamento del Atlántico, Colombia

Biological communities are made up of taxonomic groups, where phytoplankton, as primary producer, has an ecological relevance, it serves to understand the structure and functioning of an ecosystem and the way in which they interact with physicochemical parameters. In order to evaluate the richness and abundance of phytoplankton in the coastal zone of the department of Atlántico and its association with physicochemical variables and thus know its spatial and temporal changes, monitoring was carried out during 2013. Five zones were located at along the coastal zone such as Astilleros, Santa Verónica, Puerto Velero, Puerto Colombia and Mallorquín. In each zone, three stations were established, located in a straight line, with a distance between them of 5 km. For the collection of the phytoplankton and chlorophyll a (Cl-a) samples, 24 L of surface water were filtered at each of the stations, with a conical drum with a 24 µm pore diameter mesh and with 500 amber bottles. mL, respectively, which were kept in the dark. Additionally, physicochemical variables were recorded in situ. A total of 560 Cél.mL-1 of phytoplankton were identified, grouped into 47 species and five classes. The Bacillariophyceae presented the highest density and richness, followed by the Dinophyceae, Cyanophyceae, Euglenophyceae and Chlorophyceae. Chaetoceros sp. (83 Cél.mL-1) and Chaetoceros lorenzianus (64 Cél.mL-1) were the most abundant and most representative species precisely because of their abundance. Jaccard's analysis showed a dissimilarity of 80 % between stations 5A, 5B, 5C, indicating a different composition. In general, the monitoring stations that behaved as contaminated sites with a high influence of the waters of the Magdalena River.Las comunidades biológicas están conformadas por grupos taxonómicos, donde el fitoplancton, como productor primario, tiene una relevancia ecológica, sirve para comprender la estructura y funcionamiento de un ecosistema y la manera en la que interactúan con los parámetros fisicoquímicos. Con el fin de evaluar la riqueza y abundancia del fitoplancton de la zona litoral del departamento del Atlántico y su asociación con las variables fisicoquímicas y así conocer los cambios espaciales y temporales del mismo, se realizaron monitoreos durante el año 2013. Se ubicaron cinco zonas a lo largo de la zona litoral como Astilleros, Santa Verónica, Puerto Velero, Puerto Colombia y Mallorquín. En cada zona se establecieron tres estaciones, ubicadas en línea recta, con distancia entre ellas de 5 km. Para la recolecta de las muestras de fitoplancton y clorofila a (Cl-a), en cada una de las estaciones se filtraron 24 L de agua superficial, con un tambor cónico con malla de diámetro de poro de 24 µm y con botellas ámbar de 500 mL, respectivamente, las cuales se mantuvieron en oscuridad. Adicionalmente, se registraron in situ variables fisicoquímicas. Fueron identificados un total de 560 Cél.mL-1 de fitoplancton, agrupadas en 47 especies y cinco clases. Las Bacillariophyceae presentaron la mayor densidad y riqueza, seguidas de las Dinophyceae, Cyanophyceae, Euglenophyceae y Chlorophyceae. Chaetoceros sp. (83 Cél.mL-1) y Chaetoceros lorenzianus (64 Cél.mL-1) fueron las especies más abundantes y más representativa precisamente por su abundancia. El análisis de Jaccard, mostró una disimilitud de un 80 % entre que las estaciones 5A, 5B, 5C, lo que indica una composición diferente. En general las estaciones de monitoreo que comportaron como sitios contaminados con alta influencia de las aguas del río Magdalena

Simulation on mechanical properties of tungsten carbide thin films using monte carlo model

El objetivo de este trabajo es estudiar a partir de simulaciones el comportamiento mecánico de un sistema sustrato/recubrimiento. Se analizan los esfuerzos de contacto y la deformación elástica, al aplicar una carga normal a la superficie de un sistema compuesto por una película delgada resistente al desgaste de Carburo de Tungsteno (WC) y un sustrato de acero inoxidable. El análisis se basa en simulaciones utilizando el método Monte Carlo a partir del algoritmo de Metrópolis; el fenómeno fue simulado a partir de una estructura cristalina centrada en las caras fcc, tanto para el recubrimiento como para el sustrato, asumiendo el plano de deformación uniaxial en el eje z. Los resultados fueron obtenidos para diferentes valores de carga normal aplicada a la superficie del recubrimiento, obteniendo así la curva Esfuerzo vs Deformación del sistema. A partir de la curva se calculó el módulo de Young, obteniéndose un valor de 600 GPa, la cual concuerda con resultados experimentales.The aim of this paper is to study the mechanical behavior of a system composed by substrate-coating using simulation methods. The contact stresses and the elastic deformation were analyzed by applying a normal load to the surface of the system consisting of a tungsten carbide (WC) thin film, which is used as a wear resistant material and a stainless steel substrate. The analysis is based on Monte Carlo simulations using the Metropolis algorithm. The phenomenon was simulated from a fcc face-centered crystalline structure, for both, the coating and the substrate, assuming that the uniaxial strain is taken in the z-axis. Results were obtained for different values of normal applied load to the surface of the coating, obtaining the Strain-stress curves. From this curve, the Young´s modulus was obtained with a value of 600 Gpa, similar to the reports

MTHFD1 controls DNA methylation in Arabidopsis.

DNA methylation is an epigenetic mechanism that has important functions in transcriptional silencing and is associated with repressive histone methylation (H3K9me). To further investigate silencing mechanisms, we screened a mutagenized Arabidopsis thaliana population for expression of SDCpro-GFP, redundantly controlled by DNA methyltransferases DRM2 and CMT3. Here, we identify the hypomorphic mutant mthfd1-1, carrying a mutation (R175Q) in the cytoplasmic bifunctional methylenetetrahydrofolate dehydrogenase/methenyltetrahydrofolate cyclohydrolase (MTHFD1). Decreased levels of oxidized tetrahydrofolates in mthfd1-1 and lethality of loss-of-function demonstrate the essential enzymatic role of MTHFD1 in Arabidopsis. Accumulation of homocysteine and S-adenosylhomocysteine, genome-wide DNA hypomethylation, loss of H3K9me and transposon derepression indicate that S-adenosylmethionine-dependent transmethylation is inhibited in mthfd1-1. Comparative analysis of DNA methylation revealed that the CMT3 and CMT2 pathways involving positive feedback with H3K9me are mostly affected. Our work highlights the sensitivity of epigenetic networks to one-carbon metabolism due to their common S-adenosylmethionine-dependent transmethylation and has implications for human MTHFD1-associated diseases

Characterization and winemaking application of a novel pectin-degrading enzyme complex from Aspergillus sojae ATCC 20235

A novel pectin-degrading enzyme complex produced by Aspergillus sojae ATCC 20235 (PC-AS) using lowcost substrates was characterised in terms of its enzyme activities relevant in winemaking. This novel PC-AS was applied at the maceration/fermentation stage during the elaboration of 'Tempranillo' red wines to study its effect on colour development and the phenolic and amino acid wine composition. PC-AS polygalacturonase activity was the major enzyme activity detected and quantified under winemaking conditions (pH 3.5, 20 °C) and proved being stable and active in the presence of sulfur dioxide. Xylanase activity, albeit in lesser amounts, was also present in PC-AS, and neither pectinesterase, which produces methanol, nor β-glucosidase, which is detrimental to wine colour, were detected in PC-AS. This pectin-degrading complex promoted a faster colour extraction since maximum colour intensity of the enzyme treated wines was reached earlier compared to their controls. After 6 months of storage under winery conditions, wines elaborated with PC-AS presented higher concentrations of caffeic acid, coumaric acid and aspartic acid (p ˂ 0.05), suggesting an improved extraction of grape cell components. In conclusion, the application of PCAS yielded results that showed that it can be used in red winemaking to shorten the maceration time needed to reach high CI values and to improve the extraction of some phenolics and other compounds that enhance the quality of the final product.Facultad de Ciencias ExactasCentro de Investigación y Desarrollo en Fermentaciones Industriale

Global Production Increased by Spatial Heterogeneity in a Population Dynamics Model

Spatial and temporal heterogeneity are often described as important factors having a strong impact on biodiversity. The effect of heterogeneity is in most cases analyzed by the response of biotic interactions such as competition of predation. It may also modify intrinsic population properties such as growth rate. Most of the studies are theoretic since it is often difficult to manipulate spatial heterogeneity in practice. Despite the large number of studies dealing with this topics, it is still difficult to understand how the heterogeneity affects populations dynamics. On the basis of a very simple model, this paper aims to explicitly provide a simple mechanism which can explain why spatial heterogeneity may be a favorable factor for production.We consider a two patch model and a logistic growth is assumed on each patch. A general condition on the migration rates and the local subpopulation growth rates is provided under which the total carrying capacity is higher than the sum of the local carrying capacities, which is not intuitive. As we illustrate, this result is robust under stochastic perturbations