208 research outputs found

    Evaluating residents’ preferences for remediation technologies: A choice experiment approach

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    © 2017 Elsevier B.V. The choice of technologies used to remediate contaminated environments is increasingly made through engagement with a multitude of stakeholders including affected residents. Despite this, little is known about how residents perceive remediation technology applications. In this study a choice experiment is designed to explore ways of understanding and measuring residents’ preferences for different remediation technologies approaches using a sample of 944 residents in New South Wales, Australia. Analysis reveals that the residents’ acceptability of remediation technologies can be explained by both the efficacy of the technology in improving the environmental quality of the community, and the reputational value of the technology. In particular it is found that residents prefer Monitor Natural Attenuation and Bioremediation to other remediation technologies. In particular they are willing to pay an increase in yearly taxes of 44.60and44.60 and 41.15 respectively for implementing such technologies instead of alternative remediation technologies like Chemical remediation

    Modelling contingent valuation iterated elicitation data with an MCMC approach

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    The valuation of non-market goods involves iterated elicitation questions which obtain more information from the sample respondents and lead to more efficient welfare estimates. In this paper we consider the improvements which could be obtained by utilising a Bayesian MCMC approach to model this type of data. A fully informative prior resulting from previous stages is compared with a flat non-informative prior utilising both simulated and empirical data. These priors are combined with data in each stage to form the posteriors which are simulated with Gibbs sampling algorithms. The models are applied to an elicitation tree involving two successive dichotomous choice questions followed by an open-ended question. Monte Carlo simulations show that taking into account the information process implicit in successive elicitation improves the performance of the results at each stage and increases efficiency. Thus, the model allows the researcher to consider the evolving process along the elicitation tree, while increasing useful information obtained from the individual.Bayesian methods, Contingent valuation, Gibbs sampling, Iterated Elicitation, National Parks.

    Shallow structure beneath the Central Volcanic Complex of Tenerife from new gravity data: implications for its evolution and recent reactivation

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    We present a new local Bouguer anomaly map of the Central Volcanic Complex (CVC) of Tenerife, Spain, constructed from the amalgamation of 323 new high precision gravity measurements with existing gravity data from 361 observations. The new anomaly map images the high-density core of the CVC and the pronounced gravity low centred in the Las Cañadas caldera in greater detail than previously available. Mathematical construction of a sub-surface model from the local anomaly data, employing a 3D inversion based on 'growing' the sub-surface density distribution via the aggregation of cells, enables mapping of the shallow structure beneath the complex, giving unprecedented insights into the sub-surface architecture. We find the resultant density distribution in agreement with geological and other geophysical data. The modelled sub-surface structure supports a vertical collapse origin of the caldera, and maps the headwall of the ca. 180 ka Icod landslide, which appears to lie buried beneath the Pico Viejo–Pico Teide stratovolcanic complex. The results allow us to put into context the recorded ground deformation and gravity changes at the CVC during its reactivation in spring 2004 in relation to its dominant structural building blocks. For example, the areas undergoing the most significant changes at depth in recent years are underlain by low-density material and are aligned along long-standing structural entities, which have shaped this volcanic ocean island over the past few million years

    New evidence for the reawakening of Teide volcano

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    Geophysical signals accompanying the reactivation of a volcano after a period of quiescence must be evaluated as potential precursors to impending eruption. Here we report on the reactivation of the central volcanic complex of Tenerife, Spain, in spring 2004 and present gravity change maps constructed by time-lapse microgravity measurements taken between May 2004 and July 2005. The gravity changes indicate that the recent reactivation after almost a century of inactivity was accompanied by a sub-surface mass addition, yet we did not detect widespread surface deformation. We find that the causative source was evolving in space and time and infer fluid migration at depth as the most likely cause for mass increase. Our results demonstrate that, even in the absence of previous baseline data and ground deformation, microgravity measurements early in developing crises provide crucial insight into the dynamic changes beneath a volcano

    Modificación de un material didáctico interactivo en la búsqueda de un aprendizaje más adaptativo

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    Este trabajo presenta la evolución de un material didáctico interactivo orientado hacia el sistema de especificaciones geométricas de productos, ISO GPS. El grupo de Innovación Educativa Ingeniería de Fabricación de la Universidad de Las Palmas de Gran Canaria ha buscado aportar un grado de adaptatividad más alto a este material implementándolo directamente en la plataforma Moodle. Se han reorganizado los contenidos en varios bloques para mejorar su progresividad, siendo necesario superar cuestionarios de conceptos básicos para ir avanzando hacia nuevos contenidos. También se le han incorporado nuevos recursos como videos interactivos de resolución de problemas y un simulador gráfico para la visualización de las tolerancias y ajustes. Se ha empleado metodologías con la participación activa y colaborativa de estudiantes, tanto para el desarrollo como en la evaluación de este nuevo material didáctico. Los resultados obtenidos evidencian que las mejoras introducidas han tenido un impacto positivo en el aprendizaje en los estudiantes, y se ha mostrado también como una herramienta muy adecuada para su uso en una modalidad de educación híbrida que integre la docencia presencial y la telemática

    Detection of displacements on Tenerife Island, Canaries, using radar interferometry

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    Tenerife is one of the most well monitored islands of the Canaries, but the surveillance generally is centred on Las Canadas Caldera, where the Teide volcano is located. In the last 180 000 yr, the eruptions on Tenerife Island have never occurred in the same volcanic structure, except for the Teide and Pico Viejo central volcanic system, so that a complete monitoring network would have to cover the whole island. As a result, Synthetic Aperture Radar Interferometry (InSAR) is being used on Tenerife, because this space technique can provide a displacement map of the surface of the earth with centimetre precision. This paper presents the results obtained on Tenerife Island using 18 SAR images acquired by the ERS-1 and ERS-2 satellites during the period 1992-2000. Two important results have been obtained: no deformation on Las Canadas Caldera, coinciding with results obtained using terrestrial techniques, and two subsidence episodes outside monitoring areas in the NW of the island, in the region of the last historic eruptions. These results show that InSAR is a useful technique for monitoring the entire island, thus allowing us to discover deformations in areas that are not routinely or easily monitored. This technique has been used in combination with Global Positioning System (GPS) observation of a global network on the island to define a new geodetic monitoring system. The possible causes of the deformations observed have been studied in an endeavour to discern if they might be of natural origin, in particular linked to a reactivation of prior volcanic activity. Examination of the geophysical observations on the island, human activities underway and the results of the modelling seem to indicate that at least part of the deformations may be caused by changes in the groundwater level and therefore are not linked to a volcanic reactivation. This result is important because it implies that, if geodetic volcano monitoring is to be performed on the island, the system used must be capable of discerning between various possible origins of the deformation by analysing their patterns and ancillary information from other sources. In this regard, InSAR is a basic tool on account of its unpaired wide area coverage and spatial density

    A Fermented Food Product Containing Lactic Acid Bacteria Protects ZDF Rats from the Development of Type 2 Diabetes

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    Type 2 diabetes (T2D) is a complex metabolic disease, which involves a maintained hyperglycemia due to the development of an insulin resistance process. Among multiple risk factors, host intestinal microbiota has received increasing attention in T2D etiology and progression. In the present study, we have explored the effect of long-term supplementation with a non-dairy fermented food product (FFP) in Zucker Diabetic and Fatty (ZDF) rats T2D model. The supplementation with FFP induced an improvement in glucose homeostasis according to the results obtained from fasting blood glucose levels, glucose tolerance test, and pancreatic function. Importantly, a significantly reduced intestinal glucose absorption was found in the FFP-treated rats. Supplemented animals also showed a greater survival suggesting a better health status as a result of the FFP intake. Some dissimilarities have been observed in the gut microbiota population between control and FFP-treated rats, and interestingly a tendency for better cardiometabolic markers values was appreciated in this group. However, no significant differences were observed in body weight, body composition, or food intake between groups. These findings suggest that FFP induced gut microbiota modifications in ZDF rats that improved glucose metabolism and protected from T2D development

    Spain

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    This chapter presents a review of the situation concerning the various geomorphological hazards in the country, including some information about existing programmes for research, control and mitigation. With its great variety of climatic, geological and morphodynamic environments, Spain is subject to every kind of natural hazard: tsunamis, floods, volcanism, and mass movements. The whole of the territory is prone to some kind of geomorphological hazard but it is in the eastern and southern coastal strips that the risks are greatest. One of the main problems for the mitigation of geomorphological hazards in Spain is the lack of an appropriate regulatory framework for the incorporation of natural hazard assessments into land-use planning and management at the macro-, meso- and micro-planning levels. The coverage of hazard mapping is still far from complete or adequate, and much work remains to be done. There has been considerable diversity in the methods used for risk assessment and for the cartographic representation of natural hazards. An urgent need is to establish common, accepted methodologies and criteria, based on indicators defined as clearly as possible, and to standardize map legends and scales for different planning levels. Information programmes for the general public also need to be considerably expanded

    Comparative analysis of the impact of geological activity on astronomical sites of the Canary Islands, Hawaii and Chile

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    An analysis of the impact of seismic and volcanic activity was carried out at selected astronomical sites, namely the observatories of El Teide (Tenerife, Canary Islands), Roque de los Muchachos (La Palma, Canary Islands), Mauna Kea (Hawaii) and Paranal (Chile) and the candidate site of Cerro Ventarrones (Chile). Hazard associated to volcanic activity is low or negligible at all sites, whereas seismic hazard is very high in Chile and Hawaii. The lowest geological hazard in both seismic and volcanic activity was found at Roque de los Muchachos observatory, in the island of La Palma.Comment: 12 pages and 11 figure

    Downscaling Climate Change Impacts, Socio-Economic Implications and Alternative Adaptation Pathways for Islands and Outermost Regions

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    This book provides a comprehensive overview of the future scenarios of climate change and management concerns associated with climate change impacts on the blue economy of European islands and outermost regions. The publication collects major findings of the SOCLIMPACT project’s research outcomes, aiming to raise social awareness among policy-makers and industry about climate change consequences at local level, and provide knowledge-based information to support policy design, from local to national level. This comprehensive book will also assist students, scholars and practitioners to understand, conceptualize and effectively and responsibly manage climate change information and applied research. This book provides invaluable material for Blue Growth Management, theory and application, at all levels. This first edition includes up-to-date data, statistics, references, case material and figures of the 12 islands case studies. ¨Downscaling climate change impacts, socio-economic implications and alternative adaptation pathways for Islands and Outermost Regions¨ is a must-read book, given the accessible style and breadth and depth with which the topic is dealt. The book is an up-to-date synthesis of key knowledge on this area, written by a multidisciplinary group of experts on climate and economic modelling, and policy design
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