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Huesa del Común, Spain

Pardo G.,University of Seville | Aibar J.,Escuela Polytechnic Superior de Huesca | Ciria P.,Campus Universitario | Lezaun J.A.,Instituto Tecnico y de Gestion Agricola SA ITGA | Zaragoza C.,CSIC - Centro de Investigacion y Tecnologia Agroalimentaria
Chilean Journal of Agricultural Research | Year: 2011

Under semiarid conditions the response of cereal crops to chemical fertilizers and weed control practices with herbicides is often reduced. In fact, the economic profitability of agricultural production in many dryland regions is critically affected by high costs of inputs and low crop yields. As a solution, cropping systems like organic farming, obtaining similar yields and promoting environmental sustainability by reducing fertilizer and herbicides, could be an alternative to conventional systems. In this study, 23 trials were performed in five semiarid regions of Spain during 5 yr to compare different fertilizers and weed control methods on durum wheat (Triticum durum Desf.) and barley (Hordeum vulgare L.) yields. The following rotation pattern was developed on the experimental plots: fallow-barley-ground ploughed vetch (Vicia sativa L.)-durum wheat. Plots either received organic fertilizer, chemical fertilizer, or no fertilizer. In addition, three levels of weed control were applied in cereal plots: flex-tine harrow tillage, conventional herbicide, and no weeding. The results indicated that neither the fertilization nor the weed control have effect on the yield crop. Source

Nadal-Romero E.,University of Zaragoza | Vicente-Serrano S.M.,CSIC - Pyrenean Institute of Ecology | Jimenez I.,Escuela Polytechnic Superior de Huesca
Catena | Year: 2012

This study investigated the use of remote sensing data and GIS techniques in identifying badland areas and erosion risk areas, assessing the magnitude and rate of erosion processes, and estimating the geographical factors that control erosion. The remote sensing information was generated from Landsat TM and Landsat ETM+ images for the period 1984-2006, which were merged with aerial photographs. The study was performed on a 73km 2 area in a corridor of Eocene marls in the Pre-Pyrenees, an area highly prone to erosion processes. The results show that badland areas occupy approximately 2km 2 and are widespread in the study area. Various spectral indices were assessed for their performance in revealing badland dynamics; all were very useful for this purpose, and few differences were found among them. From the results we recommend the use of the simplest and most widely used spectral index: the normalized difference vegetation index (NDVI). Further analyses showed that there was a clear difference between the vegetated and degraded areas. The degraded areas showed a dominant negative trend of NDVI values, which is indicative of possible degradation processes and an increase in the surface area affected by erosion. We concluded that the degraded areas, which had poor vegetation cover and extreme environmental conditions, show a spatial pattern related to topographical location, and particularly the presence of north-facing slopes. A map of possible erosion risk was generated as a function of the initial environmental conditions and the evolution of erosion from 1984 to 2006. © 2012 Elsevier B.V.. Source

Surra J.C.,Escuela Polytechnic Superior de Huesca | Surra J.C.,CIBER ISCIII | Barranquero C.,CIBER ISCIII | Barranquero C.,University of Zaragoza | And 11 more authors.
British Journal of Nutrition | Year: 2013

Epidemiological studies have demonstrated the benefits of nut consumption on cardiovascular risk factors and CHD, attributed to their fatty acid profile, rich in unsaturated fatty acids, and also to other nutrients. The effect of nuts on atherosclerotic lesions was studied in female and male apoE-knockout mice fed a diet supplemented with 3Â % (w/w) mixed nuts (mix: almonds, hazelnuts and walnuts in a proportion of 0·25:0·25:0·50, respectively), and compared with mice receiving an isoenergetic diet of similar fat content provided as palm oil. After 12 weeks, plasma lipid parameters and aortic lesions were measured. Males receiving nuts had lower plasma cholesterol than the palm oil group, and both sex groups had lower plasma non-HDL-cholesterol and lower content of reactive oxygen species in LDL than mice receiving the palm oil diet, the latter decrease being more pronounced in females than in males. Females consuming the nut diet showed a smaller aortic lesion area than those consuming palm oil, whereas no differences were observed in males. In females, hepatic paraoxonase 2 (Pon2) mRNA increased, and no change was observed in prenylcysteine oxidase 1 (Pcyox1) expression after the consumption of the nut-containing diet. In addition, aortic atherosclerotic lesions correlated directly with total plasma cholesterol and inversely with hepatic Pon2 expression. The results suggest that the beneficial effect of nut intake in female apoE-deficient mice may be attributed to reduced non-HDL-cholesterol levels and enhanced PON2 antioxidant activity. Copyright © The Authors 2012. Source

Gabas-Rivera C.,University of Zaragoza | Barranquero C.,University of Zaragoza | Barranquero C.,CIBER ISCIII | Martinez-Beamonte R.,University of Zaragoza | And 7 more authors.
PLoS ONE | Year: 2014

Background and Purpose: Squalene, the main hydrocarbon in the unsaponifiable fraction of virgin olive oil, is involved in cholesterol synthesis and it has been reported to own antiatherosclerotic and antiesteatosic effects. However, the squalene's role on lipid plasma parameters and the influence of genotype on this effect need to be addressed. Experimental Approaches: Three male mouse models (wild-type, Apoa1- and Apoe- deficient) were fed chow semisynthetic diets enriched in squalene to provide a dose of 1 g/kg during 11 weeks. After this period, their plasma parameters and lipoprotein profiles were analyzed. Key Results: Squalene administration at a dose of 1 g/kg showed decreased reactive oxygen species in lipoprotein fractions independently of the animal background and caused an specific increase in high density lipoprotein (HDL)-cholesterol levels, accompanied by an increase in phosphatidylcholine and paraoxonase 1 and no changes in apolipoproteins A1 and A4 in wild-type mice. In these mice, the cholesterol increase was due to its esterified form and associated with an increased hepatic expression of Lcat. These effects were not observed in absence of apolipoprotein A1. The increases in HDL-paraoxonase 1 were translated into decreased plasma malondialdehyde levels depending on the presence of Apolipoprotein A1. Conclusions and Implications: Dietary squalene promotes changes in HDL- cholesterol and paraoxonase 1 and decreases reactive oxygen species in lipoproteins and plasma malondialdehyde levels, providing new benefits of its intake that might contribute to explain the properties of virgin olive oil, although the phenotype related to apolipoproteins A1 and E may be particularly relevant. © 2014 Gabás-Rivera et al. Source

Martinez-Beamonte R.,University of Zaragoza | Martinez-Beamonte R.,CIBER ISCIII | Navarro M.A.,University of Zaragoza | Navarro M.A.,CIBER ISCIII | And 12 more authors.
PLoS ONE | Year: 2013

Background and Aims: The present study was designed to verify the influence of acute fat loading on high density lipoprotein (HDL) composition, and the involvement of liver and different segments of small intestine in the changes observed. Methods and Results: To address these issues, rats were administered a bolus of 5-ml of extra-virgin olive oil and sacrificed 4 and 8 hours after feeding. In these animals, lipoproteins were analyzed and gene expressions of apolipoprotein and HDL enzymes were assessed in duodenum, jejunum, ileum and liver. Using this experimental design, total plasma and HDL phospholipids increased at the 8-hour-time-point due to increased sphingomyelin content. An increase in apolipoprotein A4 was also observed mainly in lipid-poor HDL. Increased expression of intestinal Apoa1, Apoa4 and Sgms1 mRNA was accompanied by hepatic decreases in the first two genes in liver. Hepatic expression of Abcg1, Apoa1bp, Apoa2, Apoe, Ptlp, Pon1 and Scarb1 decreased significantly following fat gavage, while no changes were observed for Abca1, Lcat or Pla2g7. Significant associations were also noted for hepatic expression of apolipoproteins and Pon1. Manipulation of postprandial triglycerides using an inhibitor of microsomal transfer protein -CP-346086- or of lipoprotein lipase -tyloxapol- did not influence hepatic expression of Apoa1 or Apoa4 mRNA. Conclusion: All these data indicate that dietary fat modifies the phospholipid composition of rat HDL, suggesting a mechanism of down-regulation of hepatic HDL when intestine is the main source of those particles and a coordinated regulation of hepatic components of these lipoproteins at the mRNA level, independently of plasma postprandial triglycerides. © 2013 Martínez-Beamonte et al. Source

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