Altieri M.A.,University of California at Berkeley |
Funes-Monzote F.R.,University of Matanzas |
Petersen P.,AS PTA
Agronomy for Sustainable Development | Year: 2012
The realization of the contribution of peasant agriculture to food security in the midst of scenarios of climate change, economic and energy crisis, led to the concepts of food sovereignty and agroecologically based production systems to gain much attention in the developing world in the last two decades. New approaches and technologies involving application of blended modern agricultural science and indigenous knowledge systems and spearheaded by thousands of farmers, NGOs, and some government and academic institutions are proving to enhance food security while conserving agrobiodiversity soil and water resources conservation throughout hundreds of rural communities in the developing world. Case studies from Cuba, Brazil, Philippines, and Africa are presented to demonstrate how the agroecological development paradigm based on the revitalization of small farms which emphasizes diversity, synergy, recycling and integration, and social processes that value community participation and empowerment, proves to be perhaps one of the only viable options to meet present and future food needs. Given the present and predicted near future climate, energy and economic scenarios, agroecology has emerged as one of the most robust pathways towards designing biodiverse, productive, and resilient agroecosystems available today. © The Author(s) 2011.
Wanderley M.C.D.A.,Federal University of Pernambuco |
Martin C.,University of Matanzas |
Martin C.,VTI Institute for Wood Technology and Wood Biology |
Rocha G.J.D.M.,CTBE - Brazilian Bioethanol Science and Technology Laboratory |
Gouveia E.R.,Federal University of Pernambuco
Bioresource Technology | Year: 2013
Enzymatic hydrolysis of pretreated sugarcane bagasse was performed to investigate the production of ethanol. The sugarcane bagasse was pretreated in a process combining steam explosion and alkaline delignification. The lignin content decreased to 83%. Fed-batch enzymatic hydrolyses was initiated with 8% (w/v) solids loading, and 10. FPU/g cellulose. Then, 1% solids were fed at 12, 24 or 48. h intervals. After 120. h, the hydrolysates were fermented with Saccharomyces cerevisiae UFPEDA 1238, and a fourfold increase in ethanol production was reached when fed-batch hydrolysis with a 12-h addition period was used for the steam pretreated and delignified bagasse. © 2012 Elsevier Ltd.
Jackson de Moraes Rocha G.,CTBE - Brazilian Bioethanol Science and Technology Laboratory |
Martin C.,University of Matanzas |
Soares I.B.,Federal University of Pernambuco |
Souto Maior A.M.,Federal University of Pernambuco |
Moraes de Abreu C.A.,Federal University of Pernambuco
Biomass and Bioenergy | Year: 2011
Integral utilisation of bagasse is a high priority for the diversification of the sugarcane industry. The application of a biorefinery philosophy to bagasse utilisation requires its fractionation into its main components: cellulose, hemicelluloses and lignin. The first stage in that process is the pretreatment, in which a considerable part of hemicelluloses is solubilised, and cellulose is activated towards enzymatic hydrolysis. In this work, a pretreatment method using a mixture of sulfuric and acetic acid is investigated. Two different solid-to-liquid ratios (1.5:10 and 1:10) were used in the pretreatment. Both conditions efficiently hydrolysed the hemicelluloses giving removals above 90%. The extractive components were also effectively solubilised, and lignin was only slightly affected. Cellulose degradation was below 15%, which corresponded to the low crystallinity fraction. The analysis of the morphology of pretreated bagasse confirmed the results obtained in the chemical characterization. © 2010 Elsevier Ltd.
Villalonga M.L.,University of Matanzas |
Diez P.,Complutense University of Madrid |
Sanchez A.,Complutense University of Madrid |
Gamella M.,Complutense University of Madrid |
And 4 more authors.
Chemical Reviews | Year: 2014
Aspects concerning neoglycoenzyme synthesis, classification, structural and functional properties, and applications are reviewed. Several chemical approaches developed to activate polysaccharide-based supports for protein immobilization were also employed for artificial glycosylation. A capital contribution to neoglycoenzymes development was performed by Marshall et al., which reported the preparation of a variety of enzyme-dextran conjugates using CNBr as the activation method. They demonstrated the effect of this chemical glycosylation on the enhanced functional stability in vitro and increased circulatory lifetime in vivo of the neoglycoenzymes. Original site-selective glycosylation methods have been also developed for the rational design and synthesis of artificial glycoenzymes with defined structure and composition. New challenges are open for neoglycoenzyme research. Artificial glycosylation has been postulated as a more biocompatible alternative to PEGylation technology, addressed to prepare enzyme drug formulations with improved pharmacokinetics and pharmacological properties.
Beruvides G.,Technical University of Madrid |
Quiza R.,University of Matanzas |
Haber R.E.,Technical University of Madrid
Information Sciences | Year: 2016
The strong points of Estimation-of-Distribution algorithms (EDAs) and specifically cross-entropy methods are widely acknowledged. One of the main advantages of EDAs is that the fusion of prior information into the optimization procedure is straightforward, thereby reducing convergence time when such information is available. This study presents the modified Multi-Objective Cross-Entropy (MOCE+) method, based on a new procedure for addressing constraints: (i) the use of variable cutoff values for selecting the elitist population; and, (ii) filtering of the elitist population after each epoch. We study the proposed method in different test suites and compare its performance with some other well-known optimization methods. The comparative study demonstrates the good figures of merit of the MOCE+ method in complex test suites. Finally, the proposed method is applied to the multi-objective optimization of a micro-drilling process. Two conflicting targets are considered: total drilling time and vibrations on the plane that is perpendicular to the drilling axis. The Pareto front, obtained through the optimization process, is analyzed through quality metrics and the available options in the decision-making process. Overall, the quality metrics of the MOCE+ method were better than the metrics of the other optimization methods considered in this work. The reported optimization of the micro-drilling process with the proposed method could potentially have a direct impact on improvements in industrial efficiency. © 2015 Elsevier Inc. All rights reserved.