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San Ramon, Peru

The University of Piura is located in Peru, the Latin American country with the highest levels of economic growth in recent years. Founded in 1969 by Josemaría Escrivá, UDEP provides quality education, promotes research and trains professionals capable of transforming society. One of the ten best universities in Peru, UDEP is renowned for its high level of academic rigor, personalized education and promotion of values. Wikipedia.

Santa-Maria M.,University of California at Davis | Ruiz-Colorado A.A.,National University of Colombia | Cruz G.,University of Piura | Jeoh T.,University of California at Davis
Bioenergy Research | Year: 2013

Banana cultivation is widespread in tropical and subtropical regions where many rural agricultural communities exist. The banana plant bears fruit once in its life cycle, leaving behind a significant amount of usable agricultural residue. Current practice leaves this residue to decompose in the field spreading diseases and polluting water supplies. We evaluated the technological feasibility of converting lignocellulosic banana residue to ethanol as a localized biofuel production strategy to improve the livelihoods of rural agricultural communities in Peru and Colombia. Liquid hot water (LHW) and steam explosion pretreatment followed by saccharification and fermentation using commercial cellulolytic enzymes and yeast strain were evaluated for three different lignocellulosic residues independently (pseudostems, leaves, and rachis). Stems and rachis, with higher glucan conversion, appeared more promising for biofuel production than leaves (up to 93 and 77 % glucose yields for rachis and pseudostems, respectively). Steam explosion pretreatment allowed higher glucan conversion for stems and leaves, while LHW was better suited for rachis. Pseudostem is the most abundant residue generated with 306,000 tons/year in Uraba Province (Colombia) and 15,000 tons/year in the Chira Valley (Peru) on a dry weight basis. Potential ethanol production in the Chira Valley was estimated in 4.8 and 76.8 ML year-1 in Colombia, processing stems and rachis combined. This study indicated that there is potential for biofuel production using the lignocellulosic banana residue, which could be expanded to other banana growing communities around the world. Process improvements such as increasing solids loading, water recycling, and optimizing fermentation are still required. © 2013 Springer Science+Business Media New York. Source

Muenchow J.,Friedrich - Alexander - University, Erlangen - Nuremberg | Feilhauer H.,Friedrich - Alexander - University, Erlangen - Nuremberg | Brauning A.,Friedrich - Alexander - University, Erlangen - Nuremberg | Rodriguez E.F.,Trujillo National University | And 3 more authors.
Journal of Vegetation Science | Year: 2013

Questions: El Niño Southern Oscillation (ENSO) is a strong driver of climatic and ecosystem variability in coastal NW Peru. La Niña amplifies the already dry local conditions, and led to depleted ecosystems in 2011. However, the 2012 La Niña event triggered rainfall far above the average. (1) Did plant species diversity, primary productivity and vegetation assemblages change along a climatic gradient between two climatologically different La Niña years; (2) Is there a difference in explanatory power of environmental predictors between the 2 yr; and (iii) is it possible to predict the observed vegetation patterns spatially? Location: Transect along a climatic gradient in the Sechura Desert of Piura, NW Peru (corresponds to the terrestrial part of the El Niño region 1 + 2) - a region of extremely high climatic variability. Methods: We visited 50 30 m × 30 m randomly sampled plots in 2011 and 2012. A Procrustes analysis of two non-metric multidimensional scaling (NMDS) ordinations provided information on the temporal change of species assemblages. Variation partitioning revealed the differences in explanatory power of the predictors. We employed a generalized additive model (GAM) to fit the scores of the first ordination axis with a floristic gradient map as a result. Results: Generally, higher rainfall resulted in a positive feedback when considering biodiversity, productivity and vegetation assemblages. The floristic gradient map resulting from the GAM displayed the spatial distribution of the three main assemblages along the climatic gradient. Edaphic variables added no independent portion to the explanation of the vegetation assemblages, but explained in conjunction with topography and NDVI a considerable amount of the variance. Conclusions: Strong Atlantic easterly winds crossing the Andes can boost plant growth even during a La Niña situation. This underscores the need for a deeper understanding of ENSO-related climate variability of ENSO. Combining vegetation maps with accurate predictions of such climatic anomalies would aid the effective execution of conservation and recovery strategies. Additionally, coupling an unconstrained ordination with a GAM appears to be a promising tool for vegetation mapping, especially in the presence of a non-linear gradient. © 2013 International Association for Vegetation Science. Source

Perez M.C.,University of Piura | Furman M.,University of San Andres
International Journal of Environmental and Science Education | Year: 2016

Designing inquiry-based science lessons can be a challenge for secondary school teachers. In this study we evaluated the development of in-service teachers’ lesson plans as they took part in a 10-month professional development course in Peru which engaged teachers in the design of inquiry-based lessons. At the beginning, most teachers designed either confirmatory or structured inquiry activities. As the course progressed, however, they started designing guided and open inquiry lesson plans. We found four factors that accounted for this change: re-evaluating the need for lab materials, revising their views on the nature of science, engaging in guided and open inquiry activities themselves, and trying out inquiry-based lessons with their own students. Our results point to the importance of engaging teachers in prolonged and varied opportunities for inquiry as part of teacher education programs in order to achieve the challenge of changing teachers’ views and practices in science education. © Author(s). Source

Ramirez F.,University of Los Andes, Colombia | Correal J.F.,University of Los Andes, Colombia | Yamin L.E.,University of Los Andes, Colombia | Atoche J.C.,University of Los Andes, Colombia | And 2 more authors.
Journal of Materials in Civil Engineering | Year: 2012

Bamboo is an excellent eco-friendly construction material because of its high renewable rate, embodied energy, reduction of pollution, high strength-to-weight ratio, and low cost. However, the use of round bamboo is limited because of its variations in dimensions, properties, and composition and the difficulty of making connections. Laminated bamboo has the potential to overcome these difficulties. Therefore, its mechanical properties and the behavior of the connections need to be established. In this research, the dowel-bearing strength of glued laminated Guadua angustifolia Kunth bamboo is experimentally determined under nail and threaded bar fasteners with different diameters and in different loading directions. A three-dimensional FEM computational model is developed with excellent agreement with experimental results. It was found that, similar to wood, the bearing strength depends on both the diameter and the specimen widthto- diameter ratio. The local behavior of the zone under the fastener is different from the bulk material. Expressions to determine these local properties as functions of the bulk properties are proposed as well as equations for the bearing strength in terms of the specimen widthto- fastener diameter ratio. © 2012 American Society of Civil Engineers. Source

Ancajima A.,University of Piura | Carrus A.,Rome University | Cinieri E.,University of LAquila | Mazzetti C.,Rome University
IEEE Transactions on Power Delivery | Year: 2010

This paper presents the results of experimental tests performed with an impulse voltage of short tail (STLI: 1.2/4μs), similar to lightning-induced overvoltages, on composite insulators used in the electric traction lines. The characteristics of volt-time breakdown under STLI waves are shown and compared with the characteristics obtained under standard lightning impulse (LI:1.2/50μ s). Models based on the disruptive effect, as proposed by Kind and Chowdhuri, are considered and applied in order to reproduce the volt-time characteristics under standard and nonstandard lightning voltages. The application viability of these models to tested insulators is considered and discussed and the accuracy in their reproduction is evaluated. It is demonstrated that the Kind model, calibrated with a suitable selection of the parameters using standard flashover data (LI), is able to estimate the response of the insulators to the short tail lightning impulses (STLI) with satisfactory accuracy. © 2009 IEEE. Source

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