33 research outputs found

    Development of a dispersive liquid-liquid microextraction coupled with magnetic dispersive microsolid phase extraction for determination of triazines in wastewater samples

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    Producción CientíficaThe combination of two microextraction techniques (dispersive liquid-liquid microextraction [DLLME] and magnetic dispersivemicrosolid phase extraction [MDMSPE]) was developed and reported for atrazine and simazine preconcentration from wastewatersamples. The proposal methodology involved the use of magnetite supports functionalized with different alkyl or phenyl groups. Themagnetic adsorbents were synthesized by the solvothermal methodassisted by microwave, characterized, and used in the samplepreconcentration of atrazine and simazine. The method validation included parameters such as the wastewater matrix effect, repeat-ability, and recovery. The analyte separation and quantification were performed by high-performance liquid chromatography withultraviolet detection (HPLC-DAD). Parameters, such as the polarity and mass of magnetic solids and pH, were evaluated to providebetter extraction performance. The highest recoveries (> 95%) were obtained with 50 mg of the phenyl group support (CS2) at pH 5,using 5 mL of the sample and carbon tetrachloride and methanol, as extraction and dispersive solvents, respectively. The lowest limitsof detection (LOD) achieved were 13.16 and 13.86 ng L−1, and the limits of quantification (LOQ) were 43.89 and 46.19 ng L−1forsimazine and atrazine, respectively, with repeatability (expressed as %RSD) below 5% in all cases. The developed method is simple,easy, and low cost for the analysis of two herbicides potentially dangerous for environmental and human health

    Generación de escenarios regionalizados de cambio climático para España

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    El presente informe resume la primera fase del proyecto del Instituto Nacional de Meteorología (INM), actualmente Agencia Estatal de Meteorología (AEMet), de generación de proyecciones regionalizadas de cambio climático para suministrar a los diferentes sectores sensibles a las condiciones climáticas. En esta fase primó la urgencia de proporcionar unas primeras estimaciones de la evolución del clima en el siglo XXI con resoluciones temporales y espaciales que pudieran ser útiles para los diferentes modelos de impacto. Esta necesidad motivó que se utilizasen tanto las bases de datos ya disponibles como los métodos suficientemente probados en otros contextos y que no se abordasen largos desarrollos que pudiesen retrasar la disponibilidad de este primer suministro de datos de proyecciones regionalizadas. Este informe tiene el carácter de documento de acompañamiento de los datos, en el que además de explicar los métodos de generación de los datos, se explican sus limitaciones en un contexto lo más amplio posible. Dentro de estas explicaciones se han incluido secciones dedicadas a describir las incertidumbres del proceso de generación de proyecciones climáticas y secciones dedicadas a discutir cuestiones metodológicas. Esta es la primera entrega de un proceso continuo de revisión periódica de las proyecciones regionales con los mejores datos procedentes de modelos globales, las mejores observaciones y las mejores técnicas de regionalización. La segunda fase del proyecto busca involucrar a la mayor parte de la comunidad científica española activa en este campo. En esta segunda fase ya no es tan prioritaria la inmediatez de los resultados como el desarrollo de nuevos métodos y la apuesta decidida por una investigación de calidad que respalde las proyecciones climáticas futuras con una mayor comprensión de las condiciones climáticas presentes y pasadas

    Valor nutrimental de harinas de vaina de mezquite (Prosopis laevigata) y efecto de su consumo en un alimento obtenido por extrusión sobre el desarrollo de dislipidemia en ratón C57BL/6J.

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    Las patologías cardiovasculares representan la mayor carga de enfermedades no transmisibles (ENT) en México y en el mundo. La génesis de estas enfermedades tiene en común el desarrollo de la placa aterosclerótica en el tejido vascular. La etapa temprana de la aterogénesis está condicionada a la existencia de dislipidemia, es decir altos niveles de colesterol y de triglicéridos asociados a altos niveles de lipoproteínas de baja densidad (LBD) y la activación del endotelio vascular, que favorecen la formación de células espumosas por acumulación de LBD oxidadas en el endotelio vascular, lo que disminuye la producción y biodisponibilidad del óxido nítrico (NO). Este ambiente aterogénico favorece la formación y evolución de la placa aterosclerótica. En la etapa temprana los antioxidantes pueden inhibir la oxidación de las LBD e incrementar la producción y biodisponibilidad del NO

    Nutritional Characterization of Prosopis laevigata Legume Tree (Mesquite) Seed Flour and the Effect of Extrusion Cooking on its Bioactive Components

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    Mesquite (Prosopis laevigata) is a legume tree widely distributed in Aridoamerica. The mature fruit of this legume is a pod, which is currently underutilized and has high nutritional potential. In the present work, mesquite seed flour is described in terms of its nutritional value, as well as the effect of extrusion cooking on its bioactive components. Mesquite seed flour is rich in fiber (7.73 g/100 g) and protein (36.51 g/100 g), with valine as the only limiting amino acid. Total phenolic compound contents in raw and extruded seed flour were 6.68 and 6.46 mg of gallic acid equivalents/g (mg GAE/g), respectively. 2-2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity values in raw and extruded seed flour were 9.11 and 9.32 mg of ascorbic acid equivalent/g (mg AAE/g), respectively. The absorbance at 290 nm, as an indicator of generation of Maillard reaction product (MRP), was the same for raw and extruded samples. Apigenin was the only flavonoid found in mesquite seed flour (41.6 mg/kg) and was stable in the extrusion process. The water absorption index (WAI) and water solubility index (WSI) were changed significantly during extrusion. The expansion of mesquite seed flour extrudates was null due to the high protein and fiber content in the sample. Extrusion cooking of mesquite seed flour is a useful form of technology for the industrialization of this underutilized and nutritionally valuable legume

    Educamadrid : integración curricular : las tecnologías de la información y la comunicación en Educación Infantil y primer ciclo de Educación Primaria : reflexiones y propuestas

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    La Consejería de Educación de la Comunidad de Madrid inició en el curso 2002-2003 el plan Educamadrid, para el desarrollo de las Tecnologías de la Información y la Comunicación (TIC) en los centros educativos. Esta publicación, mediante la aportación de reflexiones y propuestas, trata de orientar el proceso de integración de las TIC en los currículos de Educación Infantil y primer ciclo de Educación Primaria. La finalidad es que estas tecnologías sean utilizadas como recurso para la mejora de los procesos de enseñanza y aprendizaje.MadridMadrid (Comunidad Autónoma). Servicio de Formación del Profesorado. CRIF Las Acacias; General Ricardos 179 - 28025; Madrid; +34915250893; +34914660991; [email protected]

    Nutritional Characterization of Prosopis laevigata Legume Tree (Mesquite) Seed Flour and the Effect of Extrusion Cooking on its Bioactive Components

    No full text
    Mesquite (Prosopis laevigata) is a legume tree widely distributed in Aridoamerica. The mature fruit of this legume is a pod, which is currently underutilized and has high nutritional potential. In the present work, mesquite seed flour is described in terms of its nutritional value, as well as the effect of extrusion cooking on its bioactive components. Mesquite seed flour is rich in fiber (7.73 g/100 g) and protein (36.51 g/100 g), with valine as the only limiting amino acid. Total phenolic compound contents in raw and extruded seed flour were 6.68 and 6.46 mg of gallic acid equivalents/g (mg GAE/g), respectively. 2-2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity values in raw and extruded seed flour were 9.11 and 9.32 mg of ascorbic acid equivalent/g (mg AAE/g), respectively. The absorbance at 290 nm, as an indicator of generation of Maillard reaction product (MRP), was the same for raw and extruded samples. Apigenin was the only flavonoid found in mesquite seed flour (41.6 mg/kg) and was stable in the extrusion process. The water absorption index (WAI) and water solubility index (WSI) were changed significantly during extrusion. The expansion of mesquite seed flour extrudates was null due to the high protein and fiber content in the sample. Extrusion cooking of mesquite seed flour is a useful form of technology for the industrialization of this underutilized and nutritionally valuable legume

    Chemical and nutritional characterization of raw and thermal-treated flours of Mesquite (Prosopis laevigata) pods and their residual brans

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    Species of the genus Prosopis were a major staple food in Aridoamerica before the arrival of Europeans. In the present work, chemical and nutritional properties of Prosopis laevigata pods were described. The composition in weight of pods of P. laevigata was 44% mesocarp, 35% endocarp, and 21% exocarp. Sugars, including sucrose, glucose, fructose, and xylose, were important components of pods, reaching a total sugars content of 447 g/kg in mesocarp flour. Considering the FAO-recommended amino-acid scoring patterns for humans older than 3 years, high values of Lys and sulfur-containing amino acids were found in flours. Thermal treatment of flours increases significantly the phenolic compounds content and free-radical scavenging capacity, an effect associated with the generation of Maillard reaction products. Flours of mesquite pods are a good source of phenolic compounds, with significantly higher free-radical scavenging capacity than soybean and common bean
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