Matanzas, Cuba

University of Matanzas
Matanzas, Cuba

The University of Matanzas "Camilo Cienfuegos" is a university located in Matanzas, Cuba. It was founded in 1972 and is organized in 6 Faculties. Wikipedia.

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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.

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.

Oliveira F.M.V.,University of Sao Paulo | Pinheiro I.O.,University of Pernambuco | Souto-Maior A.M.,Federal University of Pernambuco | Martin C.,University of Matanzas | And 3 more authors.
Bioresource Technology | Year: 2013

Steam explosion at 180, 190 and 200°C for 15min was applied to sugarcane straw in an industrial sugar/ethanol reactor (2.5m3). The pretreated straw was delignificated by sodium hydroxide and hydrolyzed with cellulases, or submitted directly to enzymatic hydrolysis after the pretreatment. The pretreatments led to remarkable hemicellulose solubilization, with the maximum (92.7%) for pretreatment performed at 200°C. Alkaline treatment of the pretreated materials led to lignin solubilization of 86.7% at 180°C, and only to 81.3% in the material pretreated at 200°C. All pretreatment conditions led to high hydrolysis conversion of cellulose, with the maximum (80.0%) achieved at 200°C. Delignification increase the enzymatic conversion (from 58.8% in the cellulignin to 85.1% in the delignificated pulp) of the material pretreated at 180°C, but for the material pretreated at 190°C, the improvement was less remarkable, while for the pretreated at 200°C the hydrolysis conversion decreased after the alkaline treatment. © 2012 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.

Villalonga R.,Complutense University of Madrid | Villalonga M.L.,University of Matanzas | Diez P.,Complutense University of Madrid | Pingarron J.M.,Complutense University of Madrid
Journal of Materials Chemistry | Year: 2011

Superparamagnetic Fe3O4 nanoparticles were coated with (3-aminopropyl)triethoxysilane and further branched with monomethoxypolyethylene glycol chains. These nanoparticles were employed for the non-covalent surface modification of single walled carbon nanotubes, conferring them magnetic properties. This nanomaterial was employed to immobilize the enzyme xanthine oxidase in order to construct magnetically modified disposable gold screen-printed electrodes as bioelectrodes for the determination of xanthine. The electroanalytical properties of the biosensor were modulated by the nanomaterial composition, being optimal at a carbon nanotubes:magnetic nanoparticles ratio of 1:27. The resulting biosensor showed a linear dependence on the xanthine concentration in the 0.25-3.5 μM range with a fast amperometric response in 12 s. The biosensor also showed a noticeable high sensitivity of 1.31 A M-1 cm-2 and a very low detection limit of 60 nM, which can be compared advantageously with other biosensor designs for xanthine. © 2011 The Royal Society of Chemistry.

Rocha G.J.M.,CTBE - Brazilian Bioethanol Science and Technology Laboratory | Martin C.,University of Matanzas | Martin C.,VTI Institute for Wood Technology and Wood Biology | da Silva V.F.N.,University of Sao Paulo | And 2 more authors.
Bioresource Technology | Year: 2012

Five pilot-scale steam explosion pretreatments of sugarcane bagasse followed by alkaline delignification were explored. The solubilised lignin was precipitated with 98% sulphuric acid. Most of the pentosan (82.6%), and the acetyl group fractions were solubilised during pretreatment, while 90.2% of cellulose and 87.0% lignin were recovered in the solid fraction. Approximately 91% of the lignin and 72.5% of the pentosans contained in the steam-exploded solids were solubilised by delignification, resulting in a pulp with almost 90% of cellulose. The acidification of the black liquors allowed recovery of 48.3% of the lignin contained in the raw material. Around 14% of lignin, 22% of cellulose and 26% of pentosans were lost during the process. In order to increase material recovery, major changes, such as introduction of efficient condensers and the reduction in the number of washing steps, should be done in the process setup. © 2012 Elsevier Ltd.

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.

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.

Abreu J.,University of Matanzas | Rico-Juan J.R.,University of Alicante
Pattern Recognition Letters | Year: 2014

This paper presents a new algorithm that can be used to compute an approximation to the median of a set of strings. The approximate median is obtained through the successive improvements of a partial solution. The edit distance from the partial solution to all the strings in the set is computed in each iteration, thus accounting for the frequency of each of the edit operations in all the positions of the approximate median. A goodness index for edit operations is later computed by multiplying their frequency by the cost. Each operation is tested, starting from that with the highest index, in order to verify whether applying it to the partial solution leads to an improvement. If successful, a new iteration begins from the new approximate median. The algorithm finishes when all the operations have been examined without a better solution being found. Comparative experiments involving Freeman chain codes encoding 2D shapes and the Copenhagen chromosome database show that the quality of the approximate median string is similar to benchmark approaches but achieves a much faster convergence. © 2013 Elsevier B.V. All rights reserved.

About the editorial of the Professor Guillermo Llanos: "Carlos J. Finlay: the forgotten Pasteur of America", a hundred years after his death and through a documental review, a summary of the life and work of this great man of science was conducted. Finlay was a notablefigure of the American medicine, he conceived a new infection way able to explain the propagation of the yellow fever, and added the possibility of their scientific confirmation by an experimental method. For all the above-mentioned Finlay was recognized as the humanity's benefactor. © 2016. Universidad del Valle.

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