The scaled-time test as an alternative to the pseudo-dynamic test

The stepped and excessively slow execution of pseudo-dynamic tests has been found to be the source of some errors arising from strain-rate effect and stress relaxation. In order to control those errors, a new continuous test method which allows the selection of a more suitable time scale factor in the response is proposed in this work. By dimensional analysis, such scaled-time response is obtained theoretically by augmenting the inertial and damping properties of the structure, for which we propose the use of hydraulic pistons which are servo-controlled to produce active mass and damping, nevertheless using an equipment which is similar to that required in a pseudo-dynamic test. The results of the successful implementation of this technique for a simple specimen are shown here

Exotic litter of the invasive plant Ligustrum lucidum alters enzymatic production and lignin degradation by selected saprotrophic fungi

Chemical changes in leaf input to forest soils have been reported to affect decay processes. In this work, litter mass loss and decomposition constants (k) during 200 days in solid-state fermentation of the native tree Celtis tala Gill. ex Planch. and the exotic one Ligustrum lucidum Ait. with three common litter saprotrophic basidiomycetes were compared. Alterations in litter quality were characterized by solid-state 13C NMR spectroscopy, pH, soluble sugars, ammonium, proteins, and phenol content determination and were associated with extracellular lignocellulolytic enzyme production. Differences in substrate decomposition related to litter type were observed for Leratiomyces ceres, achieving a higher k in the exotic L. lucidum litter, which might be attributed to the induction of manganese peroxidase activity. Substrate preference for alkyl C and more degradation of lignified compounds were found in such substrates. Although no statistical differences in mass loss were observed for the rest of the fungi assayed, we detected changes in several of the parameters evaluated. This suggests that exotic invasions may alter ecosystem functioning by accelerating decomposition processes through an increased fungal ligninolytic activity.Fil: Mallerman, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Itria, Raúl Fabio. Instituto Nacional de Tecnología Industrial; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Alarcón Gutiérrez, Enrique. Universidad Veracruzana. Instituto de Biotecnología y Ecología Aplicada; MéxicoFil: Hernández, Christian. Universidad Veracruzana. Instituto de Biotecnología y Ecología Aplicada; MéxicoFil: Levin, Laura Noemí. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Saparrat, Mario Carlos Nazareno. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Botánica Spegazzini; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Exotic litter of the invasive plant <i>Ligustrum lucidum</i> alters enzymatic production and lignin degradation by selected saprotrophic fungi

Chemical changes in leaf input to forest soils have been reported to affect decay processes. In this work, litter mass loss and decomposition constants (k) during 200 days in solid-state fermentation of the native tree Celtis tala Gill. ex Planch. and the exotic one Ligustrum lucidum Ait. with three common litter saprotrophic basidiomycetes were compared. Alterations in litter quality were characterized by solid-state 13C NMR spectroscopy, pH, soluble sugars, ammonium, proteins, and phenol content determination and were associated with extracellular lignocellulolytic enzyme production. Differences in substrate decomposition related to litter type were observed for Leratiomyces ceres, achieving a higher k in the exotic L. lucidum litter, which might be attributed to the induction of manganese peroxidase activity. Substrate preference for alkyl C and more degradation of lignified compounds were found in such substrates. Although no statistical differences in mass loss were observed for the rest of the fungi assayed, we detected changes in several of the parameters evaluated. This suggests that exotic invasions may alter ecosystem functioning by accelerating decomposition processes through an increased fungal ligninolytic activity.Instituto de Fisiología VegetalInstituto de Botánica "Dr. Carlos Spegazzini

Exotic litter of the invasive plant <i>Ligustrum lucidum</i> alters enzymatic production and lignin degradation by selected saprotrophic fungi

Chemical changes in leaf input to forest soils have been reported to affect decay processes. In this work, litter mass loss and decomposition constants (k) during 200 days in solid-state fermentation of the native tree Celtis tala Gill. ex Planch. and the exotic one Ligustrum lucidum Ait. with three common litter saprotrophic basidiomycetes were compared. Alterations in litter quality were characterized by solid-state 13C NMR spectroscopy, pH, soluble sugars, ammonium, proteins, and phenol content determination and were associated with extracellular lignocellulolytic enzyme production. Differences in substrate decomposition related to litter type were observed for Leratiomyces ceres, achieving a higher k in the exotic L. lucidum litter, which might be attributed to the induction of manganese peroxidase activity. Substrate preference for alkyl C and more degradation of lignified compounds were found in such substrates. Although no statistical differences in mass loss were observed for the rest of the fungi assayed, we detected changes in several of the parameters evaluated. This suggests that exotic invasions may alter ecosystem functioning by accelerating decomposition processes through an increased fungal ligninolytic activity.Instituto de Fisiología VegetalInstituto de Botánica "Dr. Carlos Spegazzini

Calidad del sector metalmecánico en Colombia

En un mundo globalizado y cada vez mas competitivo el mercado exige lo mas altos estándares de los productos y servicios que las empresas ofrecen. Todas estas reglamentaciones les permite tener a las organizaciones un sello de garantía y calidad en sus productos y procesos, sin embargo, existen muchas otras empresas que aún sin contar con un sistema de gestión de calidad ofrecen productos y servicios que compiten de alguna manera con las empresas certificadas con algún Sistema de Gestión de Calidad (SGC) Para determinar que tanto influye un SGC en el nivel de calidad de los productos o servicios ofrecidos por una organización se desarrollará una investigación cuyo objetivo principal es identificar si las empresas, específicamente del sector metalmecánico en Colombia con Sistemas de Gestión de Calidad (SGC) tienen un mayor nivel de calidad comparado con aquellas que no tienen un SGC. Para desarrollar esta investigación se elaboró una encuesta en la cual se evalúan los nueve factores de calidad para empresas del sector metalmecánico en Colombia de acuerdo a Benzaquen (2013), que cuentan o no con un SGC y de esta manera determinar los niveles de cumplimiento percibidos por las empresas que poseen un sistema de gestión de calidad y las que no. El sector metalmecánico en Colombia está compuesto aproximadamente por 2.000 empresas. La encuesta se envió a cerca de 1500 compañías, obteniendo respuesta de 143 de estas. Para llevar a cabo el análisis de los resultados obtenidos se realiza un estudio del sector metalmecánico y de los factores que influyen en el sector teniendo en cuenta la gestión de la calidad en Colombia y el análisis del sector económico estudiado. Una vez realizado el análisis de resultados de la investigación obtenidos a través de encuestas realizadas a diferentes gerentes y jefes de producción de las empresas del sector metalmecánico se concluyó que no existen diferencias significativas en los 9 factores de calidad entre las empresas en el sector metalmecánico que cuentan o no con un SGC. Este resultado posiblemente se da debido a que la calidad de los productos que produce este sector debe ser optima entendiendo que la utilización de estos equipos, maquinaria y materiales deben tener altos estándares calidad y servicio para garantizar la integridad del consumidor final. Otra razón obedece a los conocimientos adquiridos por los gerentes y directores en empresas que estaban certificadas y posteriormente crearon nuevas empresas o entraron a ser parte de empresas no certificadas mejorando así los procesos y procedimientos de calidad. Aunque no se encuentran diferencias significativas en los factores de calidad para las empresas con y sin certificación, es importante que las empresas que no cuentan con un sistema de gestión de calidad sigan trabajando en obtener dicha certificación ya que para la competitividad de la empresa a nivel nacional e internacional es fundamental tener estas certificaciones.In a competitive and a globalized world the market demands the highest standards of the products and services that the companies provide, this standards allow to guarantee a excelent quality of their products and services that the companies develop. All the regulations allow the organizations to have quality and warranty in their products and services however there are other companies that don’t have a Quality Management System(QMS) and offer products and services that compete in some way with certified companies. In order to determine the impact of a QMS in the level of quality of the products or services of organizations a investigation will be going the be develop whose main objective is to identify if the companies in the methalmechanic sector in Colombia with QMS have a higher quality levels compared to those without a QMS. To develop this investigation a survey was made in wich the nine quality factors are evaluated for the companies in the methalmecanic sector of Colombia that have a QMS or not and by this way determine the levels of compliance perceived by this companies. The methalmecanic sector in Colombia is compound with approximately 2.000 companies, the survey was sent to about 1500 companies, obtaining response of 143 of these. To develop the analysis a study of the methalmechanic sector and the factors that influence considering the quality management in Colombia and the analysis of the economic sector was realized. After the analysis of the investigation results it was concluded that the quality factors between the companies in the methalmecanic sector that have or not a QMS are not affected by the fact of having a certification in QMS. This result is possibly by the quality of the products that develop this sector must have high standards and service to guarantee the integrity of the consumer. Another reason is for the knowledge acquired by managers and directors in companies that were certified so they implement them in other companies that dont have a QMS and result as a improvement in the processes and procedures of quality. Despite the diferences in the quality factors for the companies with and without certification, is important that the companies that dont have qms continue to work for the certification in order to improve the competitiveness in the market not only for national level because is also important to a international level.Tesi

7th Workshop on Agri-food Research-WiA.18

[SPA] Este libro contiene los resúmenes de los trabajos presentados al VII Workshop en Investigación Agroalimentaria (WiA. 18) organizado por el Programa de doctorado en Técnicas Avanzadas en Investigación y Desarrollo Agrario y Alimentario (TAIDA) de la UPCT y celebrado en Cartagena del 7 al 8 de mayo de 2018. El programa científico se estructura en cuatro sesiones: Biotecnología Agroalimentaria, Tecnología e Ingeniería de Alimentos, Tecnología e Ingeniería de Producción Vegetal y Ingeniería Agroforestal y Económica.[ENG] The scientific manuscripts presented in the 7th Workshop on Agri-Food Research (WIA.18) are here reported. The WiA.18 is an annual Workshop organized by the Doctoral Program in Advanced Techniques for Research and Development in Food and Agriculture (TAIDA) of the Universidad Politécnica de Cartagena - UPCT (Spain) in where PhD candidates present their research works. Presentations showed a great scientific interest and reflect the high potential of the Research Groups that belong to the several departments and institutions integrated into our PhD Program (UPCT, CEBAS-CSIC, and IMIDA). We expect that during the celebration of this Workshop, the coexistence and exchange of ideas and experiences among PhD candidates, research groups, researchers, technicians, etc.. has been favored. The scientific program is structured into four sessions: Agrifood Biotechnology, Food Technology and Engineering, Plant Production Technology and Engineering and Agroforestry and Economy Engineering, depending on the topics of interest involved in our Program. We had also two general invited lectures to strengthen the knowledge that researchers are gaining in their formation during this stage and we consider very useful for other researchers. The Scientific Organizing Committee consider that it is necessary that PhD candidates undertake this type of formative training activities to acquire the typical skills of a PhD remarking how to summarize their results, highlight the importance of them, presenting and disseminating clearly and concisely to a diverse audience in a limited time, as usually happens in the presentations at worldwide scientific conferences.The Organizing Committee acknowledges the Escuela Técnica Superior de Ingeniería Agronómica -ETSIA- and the Institute of Plant Biotechnology -IBV- of the Universidad Politécnica de Cartagena – UPCT- their assistance in making possible this event. To Mare Nostrum Campus -CMN- the dissemination done. Funding received from the International Doctorate School of UPCT is also appreciated

Plan de investigación y desarrollo tecnológico en sistemas agroforestales :resultados y avances 2003.

Los sistemas de producción agroforestales se afianzan como una alternativa de uso de la tierra en el país, como respuesta a las oportunidades y demandas de los mercados internacionales y nacionales de cultivos permanentes tropicales con fines industriales, como son las maderas finas, el cacao los frutales, el caucho entre otros que se producen en general bajo sistemas de producción agroforestales.Forestales-Foresterí

6th Workshop on Agri-food Research-WiA.17

[SPA] Este libro contiene los resúmenes trabajos presentados al VI Workshop en Investigación Agroalimentaria (WiA. 17) organizado por el Programa de doctorado en Técnicas Avanzadas en Investigación y Desarrollo Agrario y Alimentario (TAIDA) de la UPCT y celebrado en Cartagena del 8 al 9 de mayo de 2017. El programa científico se estructura en cuatro sesiones: Biotecnología Agroalimentaria, Tecnología e Ingeniería de Alimentos, Tecnología e Ingeniería de Producción Vegetal y Ingeniería Agroforestal y Económica.[ENG] The scientific manuscripts presented in the 6th Workshop on Agri-Food Research (WIA.17) are here reported. The WiA.17 is an annual Workshop organized by the Doctoral Program in Advanced Techniques for Research and Development in Food and Agriculture (TAIDA) of the Universidad Politécnica de Cartagena - UPCT (Spain) in where PhD candidates present their research works. Presentations showed a great scientific interest and reflect the high potential of the Research Groups that belong to the several departments and institutions integrated into our PhD Program (UPCT, CEBAS-CSIC, and IMIDA). We expect that during the celebration of this Workshop, the coexistence and exchange of ideas and experiences among PhD candidates, research groups, researchers, technicians, etc., has been favored. The scientific program is structured into four sessions: Agrifood Biotechnology, Food Technology and Engineering, Plant Production Technology and Engineering and Agroforestry and Economy Engineering, depending on the topics of interest involved in our Program. We also had three general invited lectures to strengthen the knowledge that researchers are gaining in their formation during this stage and we consider very useful for other researchers. The Scientific Organizing Committee consider that it is necessary that PhD candidates undertake this type of formative training activities to acquire the typical skills of a PhD remarking how to summarize their results, highlight the importance of them, presenting and disseminating clearly and concisely to a diverse audience in a limited time, as usually happens in the presentations at worldwide scientific conferences.The Organizing Committee acknowledges the Escuela Técnica Superior de Ingeniería Agronómica -ETSIA- and the Institute of Plant Biotechnology -IBV- of the Universidad Politécnica de Cartagena – UPCT- their assistance in making possible this event. To Mare Nostrum Campus -CMN- the dissemination done. Funding received from the International Doctorate School of UPCT is also appreciated

A machine learning approach to personalized predictors of dyslipidemia: a cohort study

IntroductionMexico ranks second in the global prevalence of obesity in the adult population, which increases the probability of developing dyslipidemia. Dyslipidemia is closely related to cardiovascular diseases, which are the leading cause of death in the country. Therefore, developing tools that facilitate the prediction of dyslipidemias is essential for prevention and early treatment.MethodsIn this study, we utilized a dataset from a Mexico City cohort consisting of 2,621 participants, men and women aged between 20 and 50 years, with and without some type of dyslipidemia. Our primary objective was to identify potential factors associated with different types of dyslipidemia in both men and women. Machine learning algorithms were employed to achieve this goal. To facilitate feature selection, we applied the Variable Importance Measures (VIM) of Random Forest (RF), XGBoost, and Gradient Boosting Machine (GBM). Additionally, to address class imbalance, we employed Synthetic Minority Over-sampling Technique (SMOTE) for dataset resampling. The dataset encompassed anthropometric measurements, biochemical tests, dietary intake, family health history, and other health parameters, including smoking habits, alcohol consumption, quality of sleep, and physical activity.ResultsOur results revealed that the VIM algorithm of RF yielded the most optimal subset of attributes, closely followed by GBM, achieving a balanced accuracy of up to 80%. The selection of the best subset of attributes was based on the comparative performance of classifiers, evaluated through balanced accuracy, sensitivity, and specificity metrics.DiscussionThe top five features contributing to an increased risk of various types of dyslipidemia were identified through the machine learning technique. These features include body mass index, elevated uric acid levels, age, sleep disorders, and anxiety. The findings of this study shed light on significant factors that play a role in dyslipidemia development, aiding in the early identification, prevention, and treatment of this condition

A repairability index for reinforced concrete members based on fracture mechanics

This paper proposes a repairability index for damage assessment in reinforced concrete structural members. The procedure discussed in this paper differs from the standard methods in two aspects: the structural and damage analyses are coupled and it is based on the concepts of fracture and continuum damage mechanics. The relationship between the repairability index and the well-known Park and Ang index is shown in some particular cases