Guayaquil, Ecuador

ESPOL Polytechnic University
Guayaquil, Ecuador

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Agency: European Commission | Branch: FP7 | Program: CPCSA | Phase: INFRA-2011-1.2.2. | Award Amount: 4.48M | Year: 2011

agINFRA is an Integrated Infrastructure Initiative (I3) project that will try to introduce the agricultural scientific communities into the vision of open and participatory data-intensive science. In particular, agINFRA aims to design and develop a scientific data infrastructure for agricultural sciences that will facilitate the development of policies and the deployment of services that will promote sharing of data among agricultural scientists and develop trust within and among their communities. agINFRA will try to remove existing obstacles concerning the open access to scientific information and data in agriculture, as well as improve the preparedness of agricultural scientific communities to face, manage and exploit the abundance of relevant data that is (or will be) available and can support agricultural research.\n\nUltimately, agINFRA will demonstrate how a data infrastructure for agricultural scientific communities can be set up to facilitate data generation, provenance, quality assessment, certification, curation, annotation, navigation and management.

Agency: European Commission | 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.

Chica E.J.,ESPOL Polytechnic University | Gene Albrigo L.,University of Florida
Journal of the American Society for Horticultural Science | Year: 2013

Cool ambient temperatures (5 to 20 8C) and water deficit are the only factors known to induce flowering in sweet orange (Citrus sinensis). Whereas the effects of cool ambient temperatures on flowering have been described extensively, reports on the mechanisms underlying floral induction bywater deficit in sweet orange (and other tropical and subtropical species) are scarce. We report changes in the accumulation of transcripts of four flower-promoting genes, CsFT, CsSL1, CsAP1, and CsLFY, in sweet orange trees in response to water deficit or a combination of water deficit and cool temperatures under controlled conditions. Exposure to water deficit increased the accumulation of CsFT transcripts, whereas transcripts of CsSL1, CsAP1, and CsLFY were reduced. However, when water deficit was interrupted by irrigation, accumulation of CsFT transcripts returned rapidly to pre-treatment levels and accumulation of CsSL1, CsAP1, and CsLFY increased. The accumulation of CsFT transcripts in trees during the combined water deficit and cool temperatures treatment was higher than in trees exposed to either factor separately, and accumulation of CsAP1 and CsLFY transcripts after the combined treatment was also higher. These results suggest that water deficit induces flowering through the upregulation of CsFT and that CsFT is the leaf integrator of flower-inducing signals generated by the exposure to water deficit and cool temperatures in sweet orange.

Cevallos-Cevallos J.M.,ESPOL Polytechnic University | Reyes-De-Corcuera J.I.,University of Florida
Advances in Food and Nutrition Research | Year: 2012

Metabolomics, the newest member of the omics techniques, has become an important tool in agriculture, pharmacy, and environmental sciences. Advances in compound extraction, separation, detection, identification, and data analysis have allowed metabolomics applications in food sciences including food processing, quality, and safety. This chapter discusses recent advances and applications of metabolomics in food science. © 2012 Elsevier Inc.

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.

Kryachko E.S.,NASU Bogolyubov Institute for Theoretical Physics | Ludena E.V.,Venezuelan Institute for Scientific Research | Ludena E.V.,ESPOL Polytechnic University
Physics Reports | Year: 2014

Guided by the above motto (quotation), we review a broad range of issues lying at the foundations of Density Functional Theory, DFT, a theory which is currently omnipresent in our everyday computational study of atoms and molecules, solids and nano-materials, and which lies at the heart of modern many-body computational technologies. The key goal is to demonstrate that there are definitely the ways to improve DFT. We start by considering DFT in the larger context provided by reduced density matrix theory (RDMT) and natural orbital functional theory (NOFT), and examine the implications that N-representability conditions on the second-order reduced density matrix (2-RDM) have not only on RDMT and NOFT but, also, by extension, on the functionals of DFT. This examination is timely in view of the fact that necessary and sufficient N-representability conditions on the 2-RDM have recently been attained.In the second place, we review some problems appearing in the original formulation of the first Hohenberg-Kohn theorem which is still a subject of some controversy. In this vein we recall Lieb's comment on this proof and the extension to this proof given by Pino etal. (2009), and in this context examine the conditions that must be met in order that the one-to-one correspondence between ground-state densities and external potentials remains valid for finite subspaces (namely, the subspaces where all Kohn-Sham solutions are obtained in practical applications).We also consider the issue of whether the Kohn-Sham equations can be derived from basic principles or whether they are postulated. We examine this problem in relation to ab initio DFT. The possibility of postulating arbitrary Kohn-Sham-type equations, where the effective potential is by definition some arbitrary mixture of local and non-local terms, is discussed.We also deal with the issue of whether there exists a universal functional, or whether one should advocate instead the construction of problem-geared functionals. These problems are discussed by making reference to ab initio DFT as well as to the local-scaling-transformation version of DFT, LS-DFT.In addition, we examine the question of the accuracy of approximate exchange-correlation functionals in the light of their non-observance of the variational principle. Why do approximate functionals yield reasonable (and accurate) descriptions of many molecular and condensed matter properties? Are the conditions imposed on exchange and correlation functionals sufficiently adequate to produce accurate semi-empirical functionals? In this respect, we consider the question of whether the results reflect a true approach to chemical accuracy or are just the outcome of a virtuoso-like performance which cannot be systematically improved. We discuss the issue of the accuracy of the contemporary DFT results by contrasting them to those obtained by the alternative RDMT and NOFT.We discuss the possibility of improving DFT functionals by applying in a systematic way the N-representability conditions on the 2-RDM. In this respect, we emphasize the possibility of constructing 2-matrices in the context of the local scaling transformation version of DFT to which the N-representability condition of RDM theory may be applied.We end up our revision of HKS-DFT by considering some of the problems related to spin symmetry and discuss some current issues dealing with a proper treatment of open-shell systems. We are particularly concerned, as in the rest of this paper, mostly with foundational issues arising in the construction of functionals.We dedicate the whole Section 4 to the local-scaling transformation version of density functional theory, LS-DFT. The reason is that in this theory some of the fundamental problems that appear in HKS-DFT, have been solved. For example, in LS-DFT the functionals are, in principle, designed to fulfill v- and N-representability conditions from the outset. This is possible because LS-DFT is based on density transformation (local-scaling of coordinates proceeds through density transformation) and so, because these functionals are constructed from prototype N-particle wavefunctions, the ensuing density functionals already have built-in N-representability conditions. This theory is presented in great detail with the purpose of illustrating an alternative way to HKS-DFT which could be used to improve the construction of HKS-DFT functionals. Let us clearly indicate, however, that although appealing from a theoretical point of view, the actual application of LS-DFT to large systems has not taken place mostly because of technical difficulties. Thus, our aim in introducing this theory is to foster a better understanding of its foundations with the hope that it may promote a cross-hybridization with the already existing approaches. Also, to complete our previous discussion on symmetry, in particular, spin-symmetry, we discuss this issue from the perspective of LS-DFT.Finally, in Section 6, we discuss dispersion molecular forces emphasizing their relevance to DFT approaches. © 2014 Elsevier B.V.

Ochoa X.,ESPOL Polytechnic University
CEUR Workshop Proceedings | Year: 2016

The analysis of a program curriculum is traditionally a very subjective task. Perceptions and anecdotes, faculty preferences and content or objectives check-lists are the main sources of information to undergo the revision of the structure of a program. This works proposes a list of simple metrics, that can be easily extracted from readily available academic data that contains the information about the actual interactions of students with the curriculum. These metrics, divided into time- And performance-related, are calculated at program level. The use of these metrics provides objective information in which to base discussions about the current state and efficiency of the curriculum. To exemplify the feasibility and usefulness of the metrics, this work presents some illustrative analysis that make use of the simple curriculum metrics.

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.

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.

Ochoa X.,ESPOL Polytechnic University
Journal of Emerging Technologies in Web Intelligence | Year: 2010

Connexions is a Learning Object Repository that has gained notoriety as a successful example of collaborative creation of learning materials. In a previous quantitative study about the characteristics of learning material repositories, Connexions presented some anomalies that prevented it to be classified together with other Learning Object Repositories. This paper, working with updated data, finds that those anomalies are not errors of the previous study, but that the anomalies have increased and are more strongly expressed. Moreover, those anomalies, namely the exponential growth in the number of contributors and content, seem to be the reason behind the success of Connexions. It is concluded in this work that Connexions strategy of "release early, release often", together with the openness of its core community, that welcome and support newcomers and sporadic contributors, offer a reasonable explanation for the exponential growth trends found in Connection, that can be classified now as a Social Learning Object Repository. © 2010 Academy Publisher.

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