International Nuclear Information System (INIS)

Previous studies on Venezuelan diets provided information on food consumed in each diet and their nutritional contents. It also showed the comparison of the iron absorption from these diets when given in the morning after over-night fast and when given at the customary time of the day. It was observed that the iron absorption from the lunch given at noon was slightly higher (although not significant) in Zulia and Sucre diets. There were no significant differences between the Zulia lunch given in the morning after over-night fast at noon. Similar results were observed in the Sucre diet lunch repeated twice. From these results we can state that iron absorption from meals is not affected by the time it is administered with the condition that the subjects tested have had a previous fast of three hours before the meal is administered. The significant difference in iron absorption in the first study could be due to a marked physiological daily ...

Science.gov (United States)

-Evaluacion de la fotosintesis y respiracion de especies de macroliquenes significativas en la tundra antartica. -Estudio de las isoenzimas en liquenes ...

British Library Electronic Table of Contents (United Kingdom)

Objetivo La generacion local de citocinas es un factor patogenico en el dano por isquemia-reperfusion en la disfuncion precoz del injerto. Este estudio analiza la expresion en tejido pulmonar de ARN mensajero de interleucina-8 (ARNm de IL-8) y su relacion con los cambios intersticiales pulmonares en un modelo experimental de isquemia-reperfusion pulmonar normotermica. MATERIAL Y METODOS Se estudiaron 16 conejos de la raza Nueva Zelanda en 3 grupos de estudio: a) basal; b) isquemia (lobulo inferior derecho tras isquemia de 1, 2 o 3 h), y c) reperfusion (lobulos superior y medio derechos tras 1 h de isquemia y 1, 2 o 3 h de reperfusion). Se deter- mino la expresion del ARNm de IL-8 mediante transcripcion inversa y reaccion en cadena de la polimerasa y estudio la infiltracion intersticial por...

British Library Electronic Table of Contents (United Kingdom)

The early Miocene Pedregoso Formation is one of the numerous formations rich in organic matter within the stratigraphic record of the Urumaco Trough, in the central area of the Falcon Basin. Due to its lithological characteristics and stratigraphic position, this formation is of great interest regarding the basin's petroliferous systems. The evaluation of various inorganic and organic geochemical parameters indicates that the organic matter is primarily of marine origin, deposited in a marine carbonate environment typical of reefal systems, under oxic-to-dysoxic conditions. The low variability in the TOC concentrations and in the distributions of the biomarkers extracted from the samples suggests that the paleoenvironmental conditions and the organic-matter supply remained approximately co...

Energy Technology Data Exchange (ETDEWEB)

Polyethylene pipes and connections are being widely used in treated water distribution services. Migration of low molecular weight compounds from the polyethylene into the water can change its final quality. This paper is about the concentrations and identification of the migration compounds found in treated water after staying in contact with low and high-density polyethylene. Identification and quantification were carried out using CLSA (Closed Loop Stripping Analysis) extraction technique and gas chromatography coupled to mass spectrometry (HRGC/HRMS). (Author) 12 refs.

Energy Technology Data Exchange (ETDEWEB)

This paper proposes a high accuracy numerical method to model oil spill trajectories using a particle-tracking algorithm. The Euler method, used to calculate oil trajectories, can give adequate solutions in most open ocean applications. However, this method may not predict accurate particle trajectories in certain highly non-uniform velocity fields near coastal zones or in river problems. Simple numerical experiments show that the Euler method may also introduce artificial numerical dispersion that could lead to overestimation of spill areas. This article proposes a fourth-order Runge-Kutta method with fourth-order velocity interpolation to calculate oil trajectories that minimise these problems. The algorithm is implemented in the OilTrack model to predict oil trajectories following the 'Nissos Amorgos' oil spill accident that occurred in the Gulf of Venezuela in 1997. Despite lack of adequate field information, model results compare well with ...

British Library Electronic Table of Contents (United Kingdom)

Objetivo Estudiar la evolucion de un grupo de neumonias extrahospitalarias causadas por germenes atipicos (Mycoplasma pneumoniae, Legionella spp., Coxiella burnetii y Chlamydophila pneumoniae) en funcion del tratamiento empirico recibido. Pacientes y metodos Entre enero de 1996 y febrero de 2001 ingresaron en nuestra unidad 390 casos de neumonia, de los que 89 estaban causados por germenes atipicos. Los pacientes se dividieron retrospectivamente en 2 grupos segun el tratamiento empirico pautado: grupo A, al que se habia proporcionado cobertura frente a germenes atipicos (quinolonas o macrolidos), y grupo B, al que no se habia proporcionado dicha cobertura. Se estudio la evolucion segun las diferencias entre ambos grupos en la estancia hospitalaria, la resolucion radiologica, el reingreso e...

Energy Technology Data Exchange (ETDEWEB)

Red mud (Rm) is the main by-product of the Bayer process for alumina extraction from bauxite, and grey slurries (GS) are generated during the granite rocks transformation processes. the huge volume of those wastes generated every year suppose a serious environmental problem. Recent works by our group demonstrate the efficiency of both types of muds as corrosion inhibitors for iron and steel in alkaline media containing chlorides. The elemental analysis of these slurried shows that Al{sup 3}+ is the main common element. Therefore, the aim of this paper is to study the effect of the soluble Al{sup 3}+ in the electrochemical behaviour of iron in alkaline media, in presence and absence of chlorides. The electrochemical study using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) together with surface analysis techniques allowed to conclude that Al{sup 3}+ blocks the surface of steel in alkaline media chloride increasing the steel resistance to chlorides attack. ...

Energy Technology Data Exchange (ETDEWEB)

In this thesis a study is made of the of voltage characteristics and reactive power control in the transmission network of the Electric Power Systems (EPS) with static compensators of VARs (SCVs). The necessity of voltage and reactive power control and the application of SCVs as a solution means for three representative operation stages of the EPS, considering balanced operation conditions and fundamental frequency is analyzed: Operation in the presence of incremental voltage changes, quasi-stationary operation or steady state and behavior at the occurrence of big disturbances. The application of SCVs to systems of integral transmission is in general a closed loop control system, reason why the analysis of the interaction of the system EPS-SCV is considered as an essential part of the voltage and reactive power control study. Firstly, the response analysis of the control loop is made for incremental voltage changes, representing the power system by means of its equivalent of Thevenin ...