Browsing by Author "Diaz, O."

Now showing 1 - 6 of 6
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    Characterization and microstructure of films made from mucilage of Salvia hispanica and whey protein concentrate
    (ELSEVIER SCI LTD, 2012) Munoz, L. A.; Aguilera, J. M.; Rodriguez Turienzo, L.; Cobos, A.; Diaz, O.
    Microstructural, physical and functional properties of thin films (90-110 mu m) made from blends of the mucilage of Salvia hispanica (MC) and whey protein concentrate (WPC) were studied. Two proportions of MC:WPC were used (1:3; 1:4) at pH 7 and 10 in distilled water using glycerol as plasticizer. The effects of MC: WPC ratio and pH on colour, solubility, water vapor permeability, mechanical properties and microstructure were investigated. Transmission and scanning electron microscopy were used to investigate the microstructure of aggregates and films. Films produced at pH 10 and MC:WPC ratio of 1:3 has superior mechanical properties than the other films, with higher resistance and flexibility. Also, films produced at pH 10 demonstrated better water vapour barrier (0.620 +/- 0.08 g mm/kPa h m(2)) than films at pH 7. The pH and higher proportion of polysaccharide had a positive influence on mechanical and barrier properties achieving the highest value at pH 10 and higher proportion of polysaccharide. (c) 2012 Elsevier Ltd. All rights reserved.
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    Chia seeds: Microstructure, mucilage extraction and hydration
    (ELSEVIER SCI LTD, 2012) Munoz, L. A.; Cobos, A.; Diaz, O.; Aguilera, J. M.
    Microstructural features of the chia seeds (Salvia hispanica L.) were studied by light and scanning electron microscopy. The study reports the effect of temperature (4-80 degrees C), pH (4-8) and seed:water ratio (1:20 and 1:40) on extraction of the mucilage of chia seeds and the effect of temperature (20-80 degrees C), pH (3-9) and ionic strength (0-1%) on hydration of the extracted mucilage. The mucilage was localized in cellular structures in the first three layers of the seed coat and upon full hydration filaments (mucilage fibers) became apparent and conformed to a transparent "capsule" attached to the seed. During extraction, temperature and seed:water ratio were found to have a significant effect on yield. Hydration of the extracted mucilage was significantly increased at high pH values, and was higher when salt concentration decreased, being maximal when the temperature reached values close to 80 degrees C. (C) 2011 Elsevier Ltd. All rights reserved.
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    Kinetic deterioration and shelf life in Rose hip pulp during frozen storage
    (2020) Quevedo, R.; Valencia, E.; Pedreschi Plasencia, Franco; Diaz, O.; Bastias Montes, J.; Siche, R.; Muñoz, O.
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    Monitoring of chemical elements in soils, waters and plants near the active mine tailing dam in the central zone, Chile
    (2022) Tapia, Y.; Joven, A.; Salazar, O.; Casanova, M.; Najera, F.; Kremer, C.; Castillo, B.; Diaz, O.; Pastene, R.; Acuña, E.; Antilen Lizana, Monica Paulina; Cornejo, P.
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    Monitoring of Chemical Species in Soils, Waters and Plants Near the Active Copper Mine Tailing Dam Ovejeria (Central Chile)
    (2024) Tapia, Y.; Garcia, A.; Acuna, E.; Salazar, O.; Casanova, M.; Najera, F.; Kremer, C.; Castillo, B.; Joven, A.; Diaz, O.; Pastene, R.; Antilen, M.; Cornejo, P.; Neaman, A.
    Chile, the world's largest copper producer, generates massive amounts of mine tailings that are a source of ongoing environmental concern for local communities. The main objective of this work is to evaluate the concentration of As, Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Zn and SO42- in soils, water and vegetation in the communities surrounding the Cu Ovejeria mine tailings dam, in central Chile. Soils, water and plants samples were collected from the towns of Chacabuco, Huechun, Huertos Familiares, Punta Peuco and Santa Matilde, which are located at 3 to 8 km from the mine tailings site, operated by CODELCO since 1999. The results showed that the levels of metals/metalloids and SO42- in water (pH 6.7-7.9) met both WHO limits and Chilean water quality standards for multiples uses. In soil (pH 7.7-8.4), total and available concentrations of metals/metalloids did not exceed international reference values. Plants with acceptable levels of metals and S were Citrus limon, Eucalyptus, Schinus molle, Prunus persica, Medicago sativa, Citrus sinensis and Ficus carica. The only species with Fe content well above the reference value and with high concentrations of other metals (Cu, Mn, Mo and Pb) was Acacia caven. The concentrations of chemical species determined between 2015 and 2018, in different media and locations near the active Cu tailings dam Ovejeria, in central Chile, allow to conclude that in general the levels are comparable to national and international references and do not indicate contamination.
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    Sex differences in mortality in patients with COPD
    (EUROPEAN RESPIRATORY SOC JOURNALS LTD, 2009) de Torres, J. P.; Cote, C. G.; Lopez, M. V.; Casanova, C.; Diaz, O.; Marin, J. M.; Pinto Plata, V.; de Oca, M. M.; Nekach, H.; Dordelly, L. J.; Aguirre Jaime, A.; Celli, B. R.
    Little is known about survival and clinical prognostic factors in females with chronic obstructive pulmonary disease (COPD). The aim of the present study was to determine the survival difference between males and females with COPD and to compare the value of the different prognostic factors for the disease.