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Open access

Juan Pedro Ruiz-Fernández, Javier Benlloch, Miguel A. López and Nelia Valverde-Gascueña

Abstract

The objectives in each construction process can be multiple. However, the constructions have to be carried out under some restrictions concerning price and terms. They constitute some strategic and interdependent goals. In other words, “time is money”. Several papers support that seasonal effects influence the execution rate of construction. Thus, most of them try to improve the forecasts by evaluating and joining them to the planning, although always measuring their influence indirectly. In this paper, we suggest a methodology to directly measure the influence of the seasonal factors as a whole over the earned value of construction. Additionally, we apply it to a certain case study regarding the subsidised housing of public promotion in the Castilla-La Mancha region (Spain). It is worth mentioning that our results are clarified: we have calculated the average monthly production for each month a year with respect to the annual monthly mean. Moreover, the differences regarding the average monthly production we have contributed are quite significant, and hence they have to be taken into account for each earned value forecast so that a project becomes reliable.

Open access

Mihaela Morosan, Mohamad Al Hassan, Miguel A. Naranjo, María P. López-Gresa, Monica Boscaiu and Oscar Vicente

Abstract

Genetic improvement of crop drought tolerance has become an urgent need for increasing agricultural yields and food production, to feed a growing human population in the context of global climate change. To get insights into the most relevant mechanisms underlying drought resistance in beans, we have analysed the responses to water deficit of three Phaseolus vulgaris (common bean) and one P. coccineus (runner bean) cultivars, focusing on the accumulation of specific osmolytes, a conserved response to abiotic stress in plants. Changes in osmolyte levels were correlated with the relative tolerance to water stress of the studied cultivars. Drought tolerance in Phaseolus largely depends on the accumulation of myo-inositol; glycine betaine may also contribute to tolerance in P. coccineus (but not in P. vulgaris). Proline, another common osmolyte, is a reliable marker of the level of stress affecting bean plants, but is not directly involved in tolerance mechanisms, as its drought-dependent accumulation is lowest in the most tolerant cultivar. We suggest that, by measuring the levels of proline and myo-inositol in water-stressed plants, a large number of cultivars could be easily and rapidly screened to select promising candidates to be used in breeding programmes for improving drought tolerance in beans.

Open access

Antonio Ortin-Barcelo, David J. Ortolà Morales, Michele Attilio Rosa, Domenico Fenga, Miguel A. Bañuls-Pattarelli and Fernando A. Lopez-Prats

Abstract

We present a series of cases of type A3.1.2 unstable fractures of the thoracolumbar hinge treated percutaneously with third-generation kyphoplasty and only one next level percutaneous screws. Four women aged 75 to 85 years with thoracolumbar vertebral fractures, classified as type A.3.1.2, were treated with Precept® monosegmental percutaneous fixation and the third-generation SpineJack® augmentation system.

The traditional treatment of type A3 unstable vertebral wedging fractures is performed with transpedicular fixation of two or more levels adjacent to the fracture causing great rigidity. Recently, the concept of bridge fixation combining one segment intrapedicular fixation with kyphoplasty has emerged as a more stable and less invasive system that allows greater mobility in this type of fractures. The combination of third-generation kyphoplasty and monosegmental bridge fixation may improve results to other fixation systems in type A3 vertebral fractures.