Análisis de propiedades del transporte de humedad en bloques de hormigón

The moisture absorption properties in the concrete blocks have a significant influence on the performance of the penetration of rainwater. Knowledge of these properties is necessary to have technical information that allows the construction of walls with long life. In this paper we conducted a comparative analysis of two structural concrete blocks in relation to their physical properties and moisture transport: open porosity, specific mass and the initial rate of absorption (IRA), the total absorption and uptake versus time, obtaining the sorptivity as code for measuring the absorption accurate and reliable. The results obtained show that the sorptivity in the case of concrete block D2 is not applicable and presents the absorption average curve versus time as a characterization parameter with great potential, once can be observed the behavior of the blocks from the initial time to saturation, showing the characteristics between the different block types analyzed.Las propiedades de absorción de humedad de los bloques de hormigón tienen influencias significativas en el comportamiento a la penetración de agua de lluvia. El conocimiento de estas propiedades es necesario para poder contar con información técnica que permita la construcción de paredes con vida útil prolongada. En el presente articulo se realizó un análisis comparativo de dos bloques de hormigón estructurales en relación a sus propiedades físicas y de transporte de humedad: porosidad abierta, masa especifica así como la tasa inicial de absorción (IRA), absorción total y la absorción en función del tiempo, con la obtención de la sorptividad como código de medición preciso y confiable. Los resultados mostraron que la sorptividad no es aplicable en el caso de los bloques de hormigón D2 y se presenta la curva media de absorción en función del tiempo como un nuevo parámetro de caracterización que permite analizar el comportamiento y las peculiaridades de los bloques desde el instante inicial hasta la saturación

Validation of Reference Genes for the Relative Quantification of Gene Expression in Human Epicardial Adipose Tissue

BACKGROUND: Relative quantification is a commonly used method for assessing gene expression, however its accuracy and reliability is dependent upon the choice of an optimal endogenous control gene, and such choice cannot be made a priori. There is limited information available on suitable reference genes to be used for studies involving human epicardial adipose tissue. The objective of the current study was to evaluate and identify optimal reference genes for use in the relative quantification of gene expression in human epicardial fat depots of lean, overweight and obese subjects. METHODOLOGY/PRINCIPAL FINDINGS: Some of the commonly used reference genes including 18S, ACTB, RPL27, HPRT, CYCA, GAPDH, RPLPO, POLR2A and B2M were quantified using real-time PCR analysis. The expression stability of these genes was evaluated using Genorm, Normfinder and Bestkeeper algorithms. In addition, the effect of sample size on the validation process was studied by randomly categorizing subjects in two cohorts of n = 2 and n = 33. CONCLUSIONS/SIGNIFICANCE: CYCA, GAPDH and RPL27 were identified as the most stable genes common to all three algorithms and both sample sizes. Their use as reference gene pairs might contribute to the enhanced robustness of relative quantification in the studies involving the human epicardial adipose tissue

The Science Performance of JWST as Characterized in Commissioning

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies

The Science Performance of JWST as Characterized in Commissioning

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies.Comment: 5th version as accepted to PASP; 31 pages, 18 figures; https://iopscience.iop.org/article/10.1088/1538-3873/acb29

La fabrication des combustibles nucléaires à la COGEMA.

Les auteurs présentent le contexte général dans lequel se sont organisées en France les activités de fabrication des combustibles nucléaires. Ils décrivent ensuite la conception et la fabrication des combustibles destinés aux réacteurs de la filière graphite-gaz et à ceux de la filière à neutrons rapides (Super-Phénix)

Síndrome de Tako-Tsubo. Reporte de un caso con atipicidades

El síndrome de Tako-Tsubo es una miocardiopatía aguda reversible de caracterización reciente relacionada con el estrés. Su forma típica de presentación muestra elementos clínicos, electrocardiográficos, enzimáticos y ecocardiográficos que simulan un síndrome coronarioagudo en ausencia de enfermedad coronaria obstructiva. Los métodos diagnósticos de imagen ponen en evidencia alteraciones segmentarias de la contractilidad que confieren a la geometría ventricular izquierda una forma distintiva a la cual debe su nombre. Se presenta la historia de una paciente que ingresó en nuestro hospital y cumple los criterios diagnósticos de esta entidad con algunas atipicidades.Palabras clave: Tako-Tsubo, discinesia apical transitoria, miocardiopatía con coronarias normales, síndrome del corazón roto