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Guayas, Ecuador

Perez Neira D.,Pablo De Olavide University | Perez Neira D.,State University of Milagro | Simon Fernandez X.,University of Vigo | Copena Rodriguez D.,University of Vigo | And 2 more authors.
Renewable Agriculture and Food Systems

Through the process of globalization, food has experienced an intense territorial restructuring process. Local agric-food links have weakened at the same time as daily products arrived from distant lands. There is presently a wide international debate on the importance of transport in the configuration of the agric-food system and its contribution in terms of greenhouse gas (GHG). The direct environmental costs of the transport of imported food, that is the 'external food miles', have been estimated in kilometer (km), ton (t), ton-kilometer (t-km) and GHG in Spain between 1995 and 2011. The analysis is made by ten food groups including 136 products, with special attention to the most important ones (cereals and animal feed), as well as by means of transport (air, rail, road and water) and from 113 different countries belonging to six geographical areas. Two phases are identified during this period: an expansive phase (1995-2007), in which the t-km of imported food increased from 81.8 to 147.8 million t-km and environmental pressure rose from 3.1 to 5.4 million CO2-eq t, and a recession phase (2007-2011), in which environmental pressure subsided as a consequence of the reduction of imports, even though it still remained above the 1995 level. The article reveals a clear interrelation between amounts, distances and modal distribution when it comes to determining the environmental cost of transporting food imports in the two periods studied. It also reflects on the role of the external food miles in the Spanish agri-food system from a sustainability perspective. Copyright © Cambridge University Press 2014. Source

Perez Neira D.,University of Leon | Perez Neira D.,State University of Milagro
Journal of Cleaner Production

Cacao is one of the main cultivars in Ecuador, occupying 12% of the cultivated surface. Most of the cacao is destined for exports, most specifically to be used in chocolate elaboration. Ecuador is constitutionally committed with the sustainable production of food through its National Plan of Good Living. Energy usage and its consequences in terms of Greenhouse Gases (GHG) constitute two fundamental dimensions of agrarian sustainability, especially in the context of petroleum depletion and climate change. The objective of this work is to provide a comprehensive picture of the environmental impacts (energy and GHG) of the agrifood system associated to the cacao produced in Ecuador and exported to third countries for chocolate elaboration and consumption. To that end, a life cycle assessment methodology has been utilized. The functional unit used has been defined as the elaboration and distribution, until sales, of 1 kg of pure chocolate (100% cacao) obtained from cacao cultivated in Ecuador. In the farm production phase, a differentiation has been made between technified and traditional cacao management. The study results show how the unitary energy cost of the traditional and technified agrifood systems were estimated between 36.7 and 40.6 MJ kg-1, with GHG emissions of 2.49 and 2.82 CO2 -eq kg-1, respectively. Cacao production, transformation and transportation accumulated, in average, 66.5, 16.1 and 15.0% of GHG emissions. Irrigation and fertilization constituted the two most important items in terms of energy, especially in the case of technified management. Energy efficiency (ER and ERnr) for the overall agrifood system was estimated in average terms to be 1:0.68 and 1:0.86, respectively. © 2015 Elsevier Ltd. All rights reserved. Source

Doria F.,Federal University of Rio Grande do Sul | Erichsen R.,Federal University of Rio Grande do Sul | Gonzalez M.,University of the Americas in Ecuador | Gonzalez M.,State University of Milagro | And 4 more authors.
Physica A: Statistical Mechanics and its Applications

The ability of a metric attractor neural networks (MANN) to learn structured patterns is analyzed. In particular we consider collections of fingerprints, which present some local features, rather than being modeled by random patterns. The network retrieval proved to be robust to varying the pattern activity, the threshold strategy, the topological arrangement of the connections, and for several types of noisy configuration. We found that the lower the fingerprint patterns activity is, the higher the load ratio and retrieval quality are. A simplified theoretical framework, for the unbiased case, is developed as a function of five parameters: the load ratio, the finiteness connectivity, the density degree of the network, randomness ratio, and the spatial pattern correlation. Linked to the latter appears a new neural dynamics variable: the spatial neural correlation. The theory agrees quite well with the experimental results. © 2016 Elsevier B.V. All rights reserved. Source

Gonzalez M.,State University of Milagro | Dominguez D.,Federal University of Rio Grande do Sul | Rodriguez F.B.,Autonomous University of Madrid | Sanchez A.,Rey Juan Carlos University
International Journal of Neural Systems

This work experimentally analyzes the learning and retrieval capabilities of the diluted metric attractor neural network when applied to collections of fingerprint images. The computational cost of the network decreases with the dilution, so we can increase the region of interest to cover almost the complete fingerprint. The network retrieval was successfully tested for different noisy configurations of the fingerprints, and proved to be robust with a large basin of attraction. We showed that network topologies with a 2D-Grid arrangement adapt better to the fingerprints spatial structure, outperforming the typical 1D-Ring configuration. An optimal ratio of local connections to random shortcuts that better represent the intrinsic spatial structure of the fingerprints was found, and its influence on the retrieval quality was characterized in a phase diagram. Since the present model is a set of nonlinear equations, it is possible to go beyond the naïve static solution (consisting in matching two fingerprints using a fixed distance threshold value), and a crossing evolution of similarities was shown, leading to the retrieval of the right fingerprint from an apparently more distant candidate. This feature could be very useful for fingerprint verification to discriminate between fingerprints pairs. © 2014 World Scientific Publishing Company. Source

Barrere A.,University of Washington | Stern J.E.,University of Washington | Feng Q.,FIDALAB | Feng Q.,State University of Milagro | And 2 more authors.
Sexually Transmitted Diseases

Background Although risk factors for HPV infections in young women are well defined, the risk associated with meeting male sex partners via the Internet is unclear. Methods We analyzed cross-sectional data from 282 women aged 18 to 24 years who reported using Internet dating Web sites in the past year. Women were mailed vaginal self-sampling kits for polymerase chain reaction-based HPV genotyping (including 19 oncogenic types) and sexual behavior and health history questionnaires. Generalized linear models were used to evaluate risk factors for prevalent oncogenic HPV infections. Results Thirty-five percent of women reported having met a male sex partner via the Internet in the past 6 months, and 42% reported a history of HPV vaccination. The prevalence of oncogenic HPV infection was 37%, and 9% of women tested positive for HPV-16 or HPV-18. Having met a male sex partner via the Internet in the past 6 months was not significantly associated with oncogenic HPV infection. In multivariate analyses, variables associated with an increased likelihood of oncogenic HPV infection included male partners in the past 6 months who were reported to have at least 1 concurrent partnership (adjusted prevalence ratio [aPR], 1.51; 95% confidence interval [CI], 1.11-2.06) and not always using condoms with male partners in the past 6 months (aPR, 1.86; 95% CI, 1.05-3.30). Self-reporting a history of receiving at least 1 dose of HPV vaccine was inversely associated with testing positive for HPV-16 or HPV-18 (aPR, 0.39; 95% CI, 0.16-0.97). Conclusions Although measures of recent sexual behavior were associated with prevalent oncogenic HPV infection, male partners met online were not associated with an increased likelihood of infection in this cohort of young women. © 2015 American Sexually Transmitted Diseases Association. Source

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