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Guayaquil, Ecuador

Agency: Cordis | Branch: FP7 | Program: CP-SICA | Phase: ENV.2007. | Award Amount: 2.92M | Year: 2008

The overall objective of the WETwin project is to enhance the role of wetlands in basin-scale integrated water resources management, with the aim of improving the community service functions while conserving good ecological status. Strategies will be worked out for: utilizing the drinking water supply and sanitation potentials of wetlands for the benefit of people living in the basin, while maintaining (and improving as much as possible) the ecosystem functions adapting wetland management to changing environmental conditions integrating wetlands into river basin management improving stakeholder participation and capacity building with the aim of supporting sustainable wetland management. The project will work on twinned case study wetlands from Africa, South America and Europe. Management solutions will be worked out for these wetlands with the aim of supporting the achievement of the above objectives. Involvement of local stakeholders into the planning process will play a crucial role. Knowledge and experiences gained from these case studies will be summarized in general guidelines in order to support achieving project objectives on global scale. The project also aims at supporting the global exchange of expertise on wetland management. Stakeholder participation, capacity building and expertise exchange will be supported by a series of stakeholder and twinning workshops.

Olaya P.,ESPOL Polytechnic University
Computers and Geosciences | Year: 2015

Automated-image identification and quantification of minerals, pores and textures together with petrographic analysis can be applied to improve pore system characterization in sedimentary rocks. Our case study is focused on the application of these techniques to study the evolution of rock pore network subjected to super critical CO2-injection. We have proposed a Digital Image Analysis (DIA) protocol that guarantees measurement reproducibility and reliability. This can be summarized in the following stages: (i) detailed description of mineralogy and texture (before and after CO2-injection) by optical and scanning electron microscopy (SEM) techniques using thin sections; (ii) adjustment and calibration of DIA tools; (iii) data acquisition protocol based on image capture with different polarization conditions (synchronized movement of polarizers); (iv) study and quantification by DIA that allow (a) identification and isolation of pixels that belong to the same category: minerals vs. pores in each sample and (b) measurement of changes in pore network, after the samples have been exposed to new conditions (in our case: SC-CO2-injection). Finally, interpretation of the petrography and the measured data by an automated approach were done. In our applied study, the DIA results highlight the changes observed by SEM and microscopic techniques, which consisted in a porosity increase when CO2 treatment occurs. Other additional changes were minor: variations in the roughness and roundness of pore edges, and pore aspect ratio, shown in the bigger pore population. Additionally, statistic tests of pore parameters measured were applied to verify that the differences observed between samples before and after CO2-injection were significant. © 2015 Elsevier Ltd. Source

Chavez J.P.,ESPOL Polytechnic University
International Journal of Bifurcation and Chaos | Year: 2010

We consider parameter-dependent, continuous-time dynamical systems under discretizations. It is shown that fold-Hopf singularities are O(h p)-shifted and turned into fold-NeimarkSacker points by one-step methods of order p. Then we analyze the effect of discretizations methods on the local bifurcation diagram near BogdanovTakens and fold-Hopf singularities. In particular, we prove that the discretized codimension one curves intersect at the singularities in a generic manner. The results are illustrated by a numerical example. © 2010 World Scientific Publishing Company. Source

Cardenas W.B.,ESPOL Polytechnic University
Viruses | Year: 2010

The members of the filoviruses are recognized as some of the most lethal viruses affecting human and non-human primates. The only two genera of the Filoviridae family, Marburg virus (MARV) and Ebola virus (EBOV), comprise the main etiologic agents of severe hemorrhagic fever outbreaks in central Africa, with case fatality rates ranging from 25 to 90%. Fatal outcomes have been associated with a late and dysregulated immune response to infection, very likely due to the virus targeting key host immune cells, such as macrophages and dendritic cells (DCs) that are necessary to mediate effective innate and adaptive immune responses. Despite major progress in the development of vaccine candidates for filovirus infections, a licensed vaccine or therapy for human use is still not available. During the last ten years, important progress has been made in understanding the molecular mechanisms of filovirus pathogenesis. Several lines of evidence implicate the impairment of the host interferon (IFN) antiviral innate immune response by MARV or EBOV as an important determinant of virulence. In vitro and in vivo experimental infections with recombinant Zaire Ebola virus (ZEBOV), the best characterized filovirus, demonstrated that the viral protein VP35 plays a key role in inhibiting the production of IFN-α/β. Further, the action of VP35 is synergized by the inhibition of cellular responses to IFN-α/β by the minor matrix viral protein VP24. The dual action of these viral proteins may contribute to an efficient initial virus replication and dissemination in the host. Noticeably, the analogous function of these viral proteins in MARV has not been reported. Because the IFN response is a major component of the innate immune response to virus infection, this chapter reviews recent findings on the molecular mechanisms of IFN-mediated antiviral evasion by filovirus infection. © 2010 by the authors. Source

Marti R.,University of Valencia | Sandoya F.,National Autonomous University of Mexico | Sandoya F.,ESPOL Polytechnic University
Computers and Operations Research | Year: 2013

The equitable dispersion problem consists in selecting a subset of elements from a given set in such a way that a measure of dispersion is maximized. In particular, we target the Max-Mean dispersion model in which the average distance between the selected elements is maximized. We first review previous methods and mathematical formulations for this and related dispersion problems and then propose a GRASP with a Path Relinking in which the local search is based on the Variable Neighborhood methodology. Our method is specially suited for instances in which the distances represent affinity and are not restricted to take non-negative values. The computational experience with 120 instances shows the merit of the proposed procedures compared to previous methods. © 2012 Elsevier Ltd. All rights reserved. Source

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