Plantas útiles para el futuro.

Serie documental en la que se analizan plantas, fundamentalmente situadas en zonas del Tercer Mundo, su valor y utilidad para los seres humanos, por ejemplo, el arroz, o la soja, y la moderna tecnología que debería ser transferida a estos países para un mayor aprovechamiento de la tierra.

Plantas útiles para el futuro : el cocotero.

Programa emitido el 13 de octubre de 1995

Plantas útiles para el futuro : las judías.

Programa emitido el 27 de octubre de 1995

Guía ilustrada de los principales útiles prehistóricos.

Se trata de una guía ilustrada de los principales útiles prehistóricos, considerada imprescindible para todo aquel que quiera aproximarse al estudio de esta etapa. Pretende servir de apoyo al profesorado de Enseñanza Secundaria, así como al alumno universitario, que en los estudios de Geografía e Historia se acerca al estudio más en profundidad de una disciplina como la prehistoria. En los Ciclos de Enseñanza Secundaria Obligatoria, de 12 a 14 años y de 14 a 16 años, se incluye el área de Ciencias Sociales, Geografía e Historia y dentro de ésta se incluye el concepto de las sociedades prehistóricas uno de cuyos bloques de contenidos es el de: Sociedades Históricas..

Los útiles de la cultura escolar y su narrativa en la España contemporánea.

Resumen tomado de la publicación. - El artículo pertenece a una sección monográfica de la revista dedicada a Patrimonio y educación

Recursos de historia moderna en Internet : útiles para enseñar y aprender.

El artículo forma parte de un monográfico dedicado a Internet en la enseñanza de la Historia

Orientación educativa en Internet : direcciones útiles.

El artículo forma parte de un monográfico de la revista dedicado a orientación y medios de comunicación

La opini??n de profesionales sobre la incorporaci??n de soportes tecnol??gicos port??tiles en las aulas

Resumen tomado de la publicaci??n

In vitro osteogenesis on fluorcanasite glass-ceramic with three different chemical compositions

This study aimed at investigating in vitro osteogenesis on three fluorcanasite glass-ceramic compositions with different solubilities (K3, K5, and K8). Osteoblastic cells were obtained from human alveolar bone fragments and cultured under standard osteogenic condition until subconfluence. First passage cells were cultured on K3, K5, and K8 and on Bioglass (R) 45S5 (45S5-control). Cell adhesion was evaluated at 24 h. For proliferation and viability, cells were cultured for 1, 4, and 10 days. Total protein content and alkaline phosphatase (ALP) activity were measured at 7, 14, and 21 days. Cultures were stained with Alizarin red at 21 days, for detection of mineralized matrix. Data were compared by ANOVA followed by Duncan`s test. Cell adhesion, cell proliferation, viability, total protein content, and ALP activity were not affected by fluorcanasite glass-ceramic composition and solubility. Bone-like formation was similar on all fluorcanasite-glass ceramics and was reduced compared to 45S5. The changes in the chemical composition and consequently solubility of the fluorcanasite glass-ceramics tested here did not significantly alter the in vitro osteogenesis. Further modifications of the chemical composition of the fluorcanasite glass-ceramic would be required to improve bone response, making this biomaterial a good candidate to be employed as a bone substitute.

Effects of natural weathering on microstructure and mineral composition of cementitious roofing tiles reinforced with fique fibre

The objective of the present work was to evaluate the effects of 14 years of weathering exposition on the microstructure and mineral composition of cementitious roofing tiles, still in service, reinforced with fique fibres (Furcrae gender). The results show that tiles under weathering exposition presented higher water absorption and apparent void volume than tiles under laboratory exposition. The continuous hydration of cement and natural carbonation filled the smaller pores but contrarily the large pores remained in the porous fibre to matrix interface in the samples exposed to weathering. On the other hand, their microstructure presented lower air permeability than samples aged in the internal environment of the laboratory. Besides, in the weathering aged tiles takes place a more intensive hydration process as it was identified greater amount of hydrated phases than in the laboratory aged specimens. The present results contribute to understanding the consequences of tropical weathering on the fibre-cement degradation. (C) 2010 Elsevier Ltd. All rights reserved.

Effect of accelerated carbonation on cementitious roofing tiles reinforced with lignocellulosic fibre

The present work evaluated the effects of accelerated carbonation on mechanical and physical characteristics of cementitious roofing tiles reinforced with vegetable fibre. The maximum load and toughness of the tiles have increased approximately 25% and 80% respectively as a consequence of the accelerated carbonation. Water absorption and apparent porosity decreased with carbonation while bulk density increased as a clear indication of the densification of the composite. The improvement on the mechanical performance suggests that the fibres retained their tensile strength in the inorganic matrix. Results of specimens extracted from the tested tiles after approximately 480 days in laboratory environment and further aged indicate that soak and dry cycles promoted some leaching of hydration products and more voids and lower density when performed before carbonation. The results indicate the utilization of accelerated carbonation as an effective procedure to mitigate the degradation suffered by the cellulose fibres in the less aggressive medium. (C) 2009 Elsevier Ltd. All rights reserved.

Evaluation of Recycled Tiles and OSB Ceiling Materials in Closed Broiler House Prototypes

This study aimed at evaluating the thermal performance of a modular ceiling system for poultry houses. The reduced- and distorted-scale prototypes used ceiling modules made of reforested wood and were covered with recycled long-life package tiles. The following parameters were measured for 21 days: the internal surface temperature (ST), globe temperature and humidity index (WBGT), and radiant heat load (RHL). Measurements were made at times of highest heat load (11:00 am, 13:00 pm, and 03:00 pm). Collected data were analyzed by ""R"" statistics software. Means were compared by multiple comparison test (Tukey) and linear regression was performed, both at 5% significance level. The results showed that the prototype with the ceiling was more efficient to reduce internal tile surface temperature; however, this was not sufficient to provide a comfortable environment for broilers during the growout. Therefore, other techniques to provide proper cooling are required in addition to the ceiling