Entrevista a Noam Chomsky

Abstract not availabl

Drought agroclimctic regime of a pampas semiarid región,

Las características del régimen agroclimático de sequías de un área de 100.000 kilómetros cuadrados perteneciente a la región semiárida pampeana, se deducen del análisis estadístico de veinte años de estimaciones diarias del agua útil del suelo, obtenidas aplicando el cálculo del balance hidrológico a los datos de diez estaciones meteorológicas ubicadas en el área. Por comparación con informaciones existentes sobre la ocurrencia, extensión y efectos de sequía en la zona, se establecen ciertos niveles de humedad de suelo que marcan cuatro condiciones o categorías diferenciales del fenómeno. Sobre esta base, se computan las frecuencias anuales, estacionales y mensuales, clasificadas de acuerdo al número de días en que la humedad del suelo permanece dentro de los límites de cada categoría. Se deducen gráficamente las probabilidades de ocurrencia temporal cuya distribución geográfica permite trazar las «correspondientes cartas agroclimáticas.The characteristics of drought agroclimatic regime of a 100.000 km2 area of the pampa semiarid region are evaluated applying statistical analysis to twenty years of daily available water «oil estimations by means of the meteorological water balance. Regional historic information about occurrence, extension and crop effects of the adversity is used for deriving three moisture soil levels which determine four drought categories. Based on this, the annual, seasonal and monthly frequency of days corresponding at each categories is computed. Graphical representation of this frecuencies permit to evaluate concerned probabilities. inially, in agroclimatic charts is shoved the regional geographical distribution of drought probabilities.Facultad de Ciencias Agrarias y Forestale

A risk assessment methodology to evaluate the risk failure of managed aquifer recharge in the Mediterranean Basin

Managed aquifer recharge (MAR) can be affected by many risks. Those risks are related to different technical and non-technical aspects of recharge, like water availability, water quality, legislation, social issues, etc. Many other works have acknowledged risks of this nature theoretically; however, their quantification and definition has not been developed. In this study, the risk definition and quantification has been performed by means of fault trees and probabilistic risk assessment (PRA). We defined a fault tree with 65 basic events applicable to the operation phase. After that, we have applied this methodology to six different managed aquifer recharge sites located in the Mediterranean Basin (Portugal, Spain, Italy, Malta, and Israel). The probabilities of the basic events were defined by expert criteria, based on the knowledge of the different managers of the facilities. From that, we conclude that in all sites, the perception of the expert criteria of the non-technical aspects were as much or even more important than the technical aspects. Regarding the risk results, we observe that the total risk in three of the six sites was equal to or above 0.90. That would mean that the MAR facilities have a risk of failure equal to or higher than 90 % in the period of 2–6 years. The other three sites presented lower risks (75, 29, and 18 % for Malta, Menashe, and Serchio, respectively)

Estimation of the free energy of charge transfer in molten UO

SIGLELD:9091.9F(TP--919). / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Development and validation of an HPLC method for determination of carbamazepine in human plasma

Se desarrolló y validó un método rápido y simple por HPLC para la determinación de carbamacepina en plasma humano. Las condiciones cromatográficas fueron: columna C-18, fase móvil acetonitrilo:metanol:acetato de amonio 0,05 M (30:10:60), flujo 1,2 ml/min y detección a 230 nm. Se utilizó nitrazepan como estándar interno. El método fue exitosamente aplicado a la determinación de los parámetros farmacocinéticos de carbamacepina en un voluntario sano. Durante la validación se evaluó linealidad, precisión, exactitud, límite de cuantificación y especificidad del método. La respuesta resultó lineal en el intervalo de concentraciones 0,075–3,00 μg/ml. La precisión fue menor del 5,0% expresada como coeficiente de variación. La exactitud fue del 83-99% y el límite de cuantificación fue de 0,075 μg/ml. Se demostró la especificidad del método respecto a la matriz biológica y a cafeína. La droga resultó estable en la matriz bajo las condiciones ensayadas. El método puede ser aplicado en estudios clínicos con voluntarios humanos sanos, como estudios farmacocinéticos o de bioequivalencia.A rapid and simple HPLC method for determination of carbamazepine in human plasma was developed and validated. The chromatographic conditions were: C-18 column, acetonitrile/methanol/ammonium acetate 0,05 M (30/10/60) as mobile phase; flow rate 1,2 ml/min and 230 nm detection. Plasma samples were spiked with an internal standard (nitrazepam). The method was successfully applied to determine pharmacokinetics parameters in a healthy volunteer. The method was validated with respect to linearity, precision, accuracy, limit of quantification, selectivity, specificity and stability. The response was linear for the drug concentration range from 0,075 up to 3,00 μg/ml. The RSD values for precision studies were less than 5,0%. The recovery of the drug ranged between 83-99% and the limit of quantification 0,075 μg/ml. The method was specific in relation to biological matrix and to caffeine. The drug was stable in the matrix under the studied conditions. The method can be used in clinical trials with healthy human volunteers, like bioequivalence or pharmacokinetic studies.Colegio de Farmacéuticos de la Provincia de Buenos Aire