901 research outputs found
Tratamiento enzimático en la extracción de aceite de pipa de uva, Vitis vinifera, por prensado en frÃo
The effect of enzyme incorporation is analyzed over the yield of grapeseed oil extraction by cold pressing. By this type of process the objective is to preserve grapeseed active compounds and to diminish the environmental impact in comparison to oil extraction conventional methods which use higher temperatures. The enzymatic hydrolysis takes place with a commercial enzyme previous to pressing stage. Its effectiveness is compared to a control without the biocatalyst. An oil extraction yield of 72 % d.b. is obtained with an enzymatic pre-treatment for 4 hours at 50 ºC, and 60 % of moisture, increasing in 26 % the control result. It is concluded that the incorporation of an enzymatic processing would be a feasible alternative to extract grapeseed oil under softener process conditions improving the yield of extraction in comparison to the same type of methodology without an enzyme.Se analiza el efecto de la incorporación de enzimas sobre el rendimiento de extracción de aceite por prensado en frÃo. Con el prensado en frÃo se busca preservar los compuestos activos de la pipa de uva y minimizar el impacto medioambiental en comparación con los métodos convencionales de extracción de aceite que utilizan altas temperaturas. El tratamiento enzimático se efectúa previo al prensado con una enzima comercial y su efectividad se compara con un control sin catalizador. Un rendimiento de extracción de aceite del 72 % b.s. se logra con un pre-tratamiento enzimático durante 4 horas a 50 ºC, y 60 % de humedad, superando en un 26 % al control. Se concluye que la incorporación de un tratamiento enzimático serÃa una alternativa factible para extraer el aceite de pipa de uva bajo condiciones suaves de proceso mejorando el rendimiento de extracción en comparación con el mismo tipo de proceso sin enzima
Genetic Mapping in Tetraploid Alfalfa: Results and Prospects
Among the difficulties of improving forages is their perennial nature, which necessarily requires long selection cycles to fully evaluate genotypes. Further, traits of particular importance—yield and winter hardiness—are difficult to assess on single plants, necessitating evaluation of progeny, which is both time consuming and expensive. Because of this, yield of many forages, and particularly alfalfa, has not improved substantially over the past 25 years (Riday and Brummer, 2002). Winter hardiness often has a negative correlation with autumn growth, although some evidence suggests this is not always true (Brummer et al., 2000). One way to overcome some of these limitations may be through the use of genetic markers to help select desirable genotypes. The objective of this experiment was to test the hypothesis that quantitative trait loci (QTL) for complex agronomic traits could be identified in a segregating tetraploid alfalfa population
Strain evolution in GaN Nanowires: from free-surface objects to coalesced templates
Top-down fabricated GaN nanowires, 250 nm in diameter and with various
heights, have been used to experimentally determine the evolution of strain
along the vertical direction of 1-dimensional objects. X-ray diffraction and
photoluminescence techniques have been used to obtain the strain profile inside
the nanowires from their base to their top facet for both initial compressive
and tensile strains. The relaxation behaviors derived from optical and
structural characterizations perfectly match the numerical results of
calculations based on a continuous media approach. By monitoring the elastic
relaxation enabled by the lateral free-surfaces, the height from which the
nanowires can be considered strain-free has been estimated. Based on this
result, NWs sufficiently high to be strain-free have been coalesced to form a
continuous GaN layer. X-ray diffraction, photoluminescence and
cathodoluminescence clearly show that despite the initial strain-free nanowires
template, the final GaN layer is strained
Composición y amplitud de la dieta del águila real en Chihuahua, México
We assessed golden eagle (Aquila chrysaetos canadensis) diet and breadth composition during the breeding season 2010 in Chihuahua state, Mexico. We collected old and fresh prey remains and observed prey delivery in active territories. Diet was diverse and composedof small mammals, mainly, but includes birds and reptiles as well. Hares and rabbits were the most important in terms of relativeabundance and biomass
- …