Biomethane production improvement by enzymatic pretreatments and enhancers of sewage sludge anaerobic digestion

Enzymatic hydrolysis is recognised as an effective pre-treatment for increasing biodegradability of sludge. In this work, isolated commercial enzymes as well as in-situ enzymes producer bacteria were used respectively as enhancers and pre-treatments of sewage sludge. Biodegradability of sample as well as biomethane potential production were studied. Results showed that depuration efficiencies in terms of CODs (73.5-85.5 %) and TVS (28.5-42.7 %) were more than twice the control value. In addition, pre-treated samples as well as enhanced samples with enzymes generated more biomethane than control. The optimal ones, were those with the isolated proteases (P) and with bacteria (Bacillus licheniformis) treatment in-situ (F), producing a total volume of 72.4 ± 2.62 ml CH4 and 114 ml ± 0.46 CH4, respectively, increasing the biogas volume in 3.65 and 5.77 times respectively compared with control

Robust high-accuracy high-speed continuous-time CMOS current comparator

The authors present a CMOS current comparator which employs nonlinear negative feedback to obtain high-accuracy (down to 1.5pA) and high-speed for low input currents (8ns at 50nA). The new structure features a speed improvement of more than two orders of magnitude for a 1 nA input current, when compared to the fastest reported to date

Áreas metropolitanas en transformación. Presente y futuro del Corredor del Henares en el área funcional madrileña

This work analyzes the economic, social and territorial recent changes of the Corredor del Henares, a classic axis of economic concentration and diffusion related to Madrid growth. The aim of this work is to know something more about the processes of change which are being carried out in metropolitan areas around this site. These processes are related to deep transformations in the global productive system, which produce new situations of spatial integration and compartmentalization. The Corredor del Henares is an example of this new situation, which becomes apparent through the functional transformation and the incorporation of new territories into the metropolitan area of Madrid. This study delimits the current area of the Corredor del Henares, indicates the elements which define its proper accessibility, analyzes the sense of the transformations in its productive structure and relates the forecast of new soil for economic activities to the demand of this product.Ce document analyse les plus récents changements économiques, sociales et territoriales du Corredor del Henares, un axe classique de concentration et de diffusion économique lié à l’agglomération de Madrid. La connaissance des processus de changement qui sont réalisés dans les zones métropolitaines européennes c’est but de ce travail. Ces processus sont liés aux transformations du système mondial de production, tout en créant des nouvelles situations d’intégration et de cloisonnement de l’espace. Le Corredor del Henares est un très bon exemple des transformations économiques actuelles et de l’incorporation des nouveaux territoires au région fonctionnel traditionnelle. L’étude définit l’espace fonctionnel actuel du Corredor, et aussi il délimite les éléments qui définissent sa bonne accessibilité. Au meme temps l’étude analyse les transformation de sa structure productive et il établie les relations entre les prévisions de nouvel espace, pour les activités économiques, avec la demande finale de ce produit.El trabajo analiza los recientes cambios económicos, sociales y territoriales del Corredor del Henares, eje clásico de concentración y difusión económica vinculado a la aglomeración madrileña. Su objetivo es conocer algo más de los procesos de cambio que se llevan a cabo en áreas metropolitanas de nuestro entorno relacionados con trasformaciones profundas en el sistema productivo global que dan lugar a nuevas situaciones de integración y compartimentación espacial. El Corredor del Henares es un ejemplo expresivo de la nueva situación que se manifiesta en su transformación funcional y en la incorporación de nuevos territorios al área metropolitana madrileña. El estudio delimita el actual ámbito del Corredor del Henares, indica los elementos que definen su buena accesibilidad, analiza el sentido de las transformaciones de su estructura productiva y relaciona las previsiones de nuevo suelo para actividades económicas con la demanda final de este producto

A mismatch-insensitive high-accuracy high-speed continuous-time current comparator in low voltage CMOS

This paper presents a CMOS current comparator which employs nonlinear feedback to obtain high-accuracy (down to 1.5 pA) and high-speed for low input currents (8 ns@50 nA). This structure is much faster for low currents (below 10 /spl mu/A) than other previous nonlinear feedback comparators. Particularly, when compared to the fastest current comparator reported up to now, the new one operates at more that 100 times faster for a 1 nA current, with smaller area occupation and similar power consumption. In addition, the new comparator is virtually insensitive to mismatch and capable of operating with supply voltages as low as 1 V

Relevance of Social, Economic, and Environmental Impacts on Residents’ Satisfaction with the Public Administration of Tourism

Those in charge of tourism destinations face the need to create tourism development models compatible with the essence of the localities that they manage. These models have to be sustainable, both environmentally and socially, and also must become drivers of the local economy. However, tourists also generate negative impacts in the locality which, when they are perceived by the residents, can give rise to a rejection of visitors. Hence, improving the tourism management is necessary. This is why to know the residents’ perceptions about the impacts of tourism is essential. Moreover, measuring the impact effects on their satisfaction with the public administration of the destination can be of great usefulness. This study falls into this research line, as it proposes a model to measure these impacts and their effect on satisfaction. To do so, an empirical study is performed among residents in the city of Seville (southern Spain, one of the most visited destinations in the world), based on subjective economic, social, and environmental indicators. The results show that the citizens value three types of impacts, the social impact coming after the economic impact as to its influence on their satisfaction with the administration. Based on this, we postulate that the efforts made to attract events to the city, or to improve connections to access a broader market, must be approached as public procurements in which selection criteria that are compatible with the destination’s positioning and strategy prevail. Social and environmental criteria should be considered among these criteria

Fire analysis of timber-framed walls lined with gypsum

This investigation analyses the influence of the depth and the distance between studs on the fire resistance of lightweight timber-framed (LTF) walls lined with gypsum plasterboards. The simplified model used to determine the fire resistance in Eurocode EN 1995-1-2 provides very conservative values, as few parameters are considered. The new generation of Eurocode EN 1995-1-2 includes an upgrade of the simplified model, allowing us to predict the fire resistance of LTF wall assemblies more accurately. This separating function method considers the number, the thickness and the material of the protection layers, but does not explicitly consider the variation of the depth and the distance between the studs for the calculation of the insulation time of the assembly, besides including some limitations for both parameters. To demonstrate the influence of these parameters, 36 numerical simulations were carried out using the finite element method previously validated with experimental tests. The results obtained from the parametric analyses confirmed that such parameters affect the fire resistance of the LTF wall assemblies in a significant way. In addition, the results revealed an important contribution in the study of LTF wall assemblies against fire resistance, demonstrating the need for including extra geometric parameters in the simplified model in order to increase the accuracy of current models.info:eu-repo/semantics/publishedVersio

Cultural Historical Psychology and the Reset of History

The authors argue that, in the research trajectory of cultural historical psychology, there are nuclear aspects of Vygotsky’s theory that have been insufficiently considered. Three of these aspects are herein discussed: the intense and rapid changes to mediational processes and their influence on human psyche; meaningful findings on neuroplasticity that require a neuropsychological approach; and, perhaps most importantly, the need for cultural historical approach, and for psychology at large, to return to the study of the direction and meaning of human life

Descripción de la metodología y los resultados obtenidos en un estudio prospectivo europeo sobre seguridad de la inmunoterapia en la práctica clínica habitual

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Pediatría. Fecha de lectura: 14-11-201