Performance and emissions of a CI-ICE fuelled with Jatropha biodiesel blends and economic and environment assessment for power generation in non-interconnected areas

An experimental investigation into the effects of Jatropha biodiesel (JB) blends on the performance and emissions of a diesel engine was performed, and an economic and environmental assessment of the Jatropha curcas L. (JCL) crop for JB production and its use was also presented. The results revealed that when the engine operates with JB blends in proportions of up to 10%, the brake-specific fuel consumption (BSFC) increases to 37.5% at full engine load, and the engine’s thermal efficiency is reduced by 10% regarding diesel operation. A reduction in the specific emissions of carbon monoxide, unburned hydrocarbons, and particulate matter with JB blends of up to 75% of the engine load was found. On the other hand, specific carbon dioxide and nitrogen oxide emissions, with regard to diesel, increased by 21.8 and more than 100%, respectively. The lower heating value (LHV) was the property that most influenced the engine’s performance and emissions fuelled with JB blends, because JB has a lower value of LHV than diesel. Finally, the economic and environmental assessment showed that Colombian soil is well-suited to JCL crops. The use of JB instead of palm biodiesel could mean a decrease of 27,730 USD/day and 1588 kg/day of CO2 emissions

Nueva técnica para la recolocación emergente del Impella desplazado

To the Editor, The use of circulatory support has grown exponentially over the last decade, particularly for the management of cardiogenic shock in the setting of acute myocardial infarction.1,2 The devices more often used like the Impella CP (Abiomed, United States) show good results in observational studies. These studies describe an improved survival rate when these devices are used as part of a well-defined program to treat cardiogenic shock.3-5 However, this is not a risk-free therapy, and device displacement is a complication that can occur while the patient is being moved or transferred. Although rare, this complication can be deadly if not solved immediately because there is a loss of hemodynamic support. In these cases, the device needs to be retrieved due to the impossibility of crossing the aortic valve to proceed with a new implant

School Dropout of Adolescent Mothers in a Colombian-Venezuelan Border

The objective of this study was to compare school dropout of adolescent mothers in the Venezuelan-Colombian border, between the Táchira State and the North of Santander Department. The factors considered by the analysis were the age when leaving their studies, the educational level and the school performance before the desertion for determining the requirements conducive to social development. Thus, using a quantitative methodology, the study handles two samples: 235 adolescent mothers in Táchira State and 406 mothers in the North of Santander Department. The results indicate, for both contexts, a statistically significant association between school dropout before pregnancy with age at the time of dropout of school, with the educational level upon leaving school and the independence with previous academic performance. The study revealed that, in the abandonment of studies, the sociological age influences by an advance of roles not linked to chronological age. The conclusion is that a quality education that involves professional preparation and stops adolescent pregnancy through curricular planning according to childhood and youth that motivates intrinsically and extrinsically towards a better future is required in the studied reality

Rejection of trace pharmaceutically active compounds present in municipal wastewaters using ceramic fine ultrafiltration membranes: Effect of feed solution pH and fouling phenomena

[EN] This study investigates the influence of feed solution pH and fouling on the rejection of ten selected pharmaceutically active compounds (PhACs) with different physicochemical characteristics (molecular weight, water solubility, log Kow, pKa, dipole moment, etc.) by three multichannel ceramic ultrafiltration membranes, ranging from 1 to 8 kDa, in order to improve their removal from water. For this purpose, the comparison between filtration of PhACs in deionised water (Feed I) and in real wastewater effluent (Feed II) was performed, demonstrating that the variation of pH and the formation of a foulant layer altered the separation mechanism and hence the rejection values of each PhAC varied. Higher rejections of most of the PhACs were higher at slightly alkaline pH, especially for anionic compounds in the filtration with real wastewater. In these conditions, flux decline was more severe. The formed fouling layer onto the hydrophilic membrane surface acted as a secondary barrier for separation with different properties like hydrophobicity and charge. Electrostatic interactions were the main separation mechanism in the filtration of PhACs in deionised water, while the hydrophobic/hydrophilic interactions played a crucial role in the filtration experiments with real wastewater effluent. Thus, the reported results indicated that the rejection of pharmaceutically active compounds was strongly pH-dependent, except for hydrophilic neutral compounds (acetaminophen and caffeine), which showed a pH-independent behaviour with low rejection values. (C) 2016 Elsevier B.V. All rights reserved.The authors of this work wish to gratefully acknowledge the financial support from the Spanish Ministry of Economy and Competitiveness through the project CTM2013-42342-P.García-Ivars, J.; Dura-Maria, J.; Moscardo-Carreño, C.; Carbonell Alcaina, C.; Alcaina-Miranda, MI.; Iborra Clar, MI. (2017). Rejection of trace pharmaceutically active compounds present in municipal wastewaters using ceramic fine ultrafiltration membranes: Effect of feed solution pH and fouling phenomena. Separation and Purification Technology. 175:58-71. https://doi.org/10.1016/j.seppur.2016.11.027S587117

Rentabilidad privada de las granjas porcinas en el sur del Estado de México

La rentabilidad privada y la eficiencia de los costos privados son indicadores de competitividad en las granjas porcinas. El presente estudio se realizó en el Sur del Estado de México en 2006, y se basó en información proveniente de sesenta porcicultores de traspatio, dos de granjas semitecnificadas y una tecnificada. La Matriz de Análisis de Política fue el método usado y consiste en una serie de matrices de coeficientes técnicos y de precios de los insumos y del producto, con los que se derivó la matriz de presupuesto privado. Los tres sistemas productivos presentaron una rentabilidad positiva a precios privados, que variaron de 11 a 13 %. Asimismo, las relaciones de costo privado se situaron entre 0.53 y 0.58, lo que sugiere una alta competitividad. Para 2006 se concluyó que la producción porcícola de los sistemas mencionados permitió pagar el valor de mercado de factores internos, incluyendo la tasa de retorno normal del capital, y que la actividad productiva fue redituable en función de los precios recibidos y pagados

Implementación de estrategias lectoras y analíticas de textos por medio de herramientas tecnológicas didácticas con estudiantes del grado sexto de la institución educativa José María Carbonell del municipio de Arauquita

El desarrollo de la investigación busca ofrecer posibles alternativas frente al bajo nivel lector de los jóvenes; tomando este problema como un factor de significativa influencia en el proceso educativo. Se propone formular estrategias de cambio en la manera de presentar información haciendo uso de las nuevas tecnologías, esto tomando en cuenta que los jóvenes son nativos digitales situación que ofrece desventaja frente a su visión del mundo digital y de cómo ha de ser presentada la información. Este proyecto se dirige a estudiantes de grado sexto de la institución educativa José María Carbonell del municipio de Arauquita

Sentido de la Escuela para niños y niñas mapuche en una zona rural

El presente artículo se enmarca en el campo de la comprensión acerca del sentido que se le otorga a la escuela. En este caso se contextualiza la pregunta en estudiantes mapuche que asisten a un colegio rural de alta vulnerabilidad socioeconómica. A través de un enfoque cualitativo se buscó principalmente comprender el sentido que le dan niños y niñas a la escuela y las motivaciones que tienen para asistir. Participaron 20 niños y niñas en dos grupos focales. Luego de los análisis iniciales se procedió a volver al campo realizando diez entrevistas individuales. Los resultados muestran que el sentido de la escuela se configura tanto por motivaciones internas como expectativas que tienen los padres sobre el futuro de sus hijos. Desde la mirada de los estudiantes, tanto profesores como padres motivan a los estudiantes a salir de la ruralidad, a seguir estudios superiores como una fórmula de éxito social.Cet article s’inscrit dans le champ de compréhension lié à la signification attribuée à l’école. Dans ce cas présent, la question est posée à des étudiants mapuche scolarisés dans un collège rural de grande vulnérabilité socio-économique. L’approche qualitative vise principalement à comprendre le sens que ces filles et garçons attribuent à l’école et leurs motivations pour y assister. 20 garçons et filles ont participé à cette étude répartis entre deux focus groupes. Après avoir entrepris les analyses initiales, un retour sur le terrain fut mené sous la forme de dix entretiens individuels. Les résultats montrent que la signification de l’école se base aussi bien sur des motivations internes que des attentes propres aux parents quant au future de leurs enfants. D’après la vision des étudiants, tant les enseignants que les parents incitent les étudiants à sortir de la ruralité, à poursuivre des études supérieurs considérées comme une formule pour la réussite sociale.This article is framed in the area of understanding about the significance given to School. In this case the issue is contextualized in Mapuche students who attend a rural elementary school with socioeconomic vulnerability. Through a qualitative approach was sought primarily to understand the meaning that children give to school and the motivations to attend. Twenty children participated in two focus groups. After initial analysis we proceeded to return to the field conducting ten personal interviews. The results show that the significance of school is set both by internal motivations of the children as expectations of parents about their children’s future. From the perspective of the students, both teachers and parents encourage them to get out of rurality, to pursue higher education as a social success formula.Este artigo é parte do campo de compreensão sobre o significado que é dado para a escola. Neste caso, a questão é contextualizada em alunos mapuches que freqüentam uma escola rural de alta vulnerabilidade socioeconômica. Através de uma abordagem qualitativa foi procurado principalmente para entender o significado que dão às crianças para a escola e as motivações para participar. 20 crianças participaram de dois grupos de foco, após análises iniciais começou a voltar para o campo realizar 10 entrevistas. Os resultados mostram que a direção da escola está definida tanto por motivações internas como as expectativas dos pais sobre o futuro dos seus filhos. A partir do olhar de estudantes, professores e pais incentivam os alunos a sair da ruralidade, para prosseguir o ensino superior como uma fórmula de sucesso social

Uncertainty Analysis in New Seismic Hazard Study of Spain Aimed at the Revision of the Spanish Building Code.

In this paper we present a global overview of the recent study carried out in Spain for the new hazard map, which final goal is the revision of the Building Code in our country (NCSE-02). The study was carried our for a working group joining experts from The Instituto Geografico Nacional (IGN) and the Technical University of Madrid (UPM) , being the different phases of the work supervised by an expert Committee integrated by national experts from public institutions involved in subject of seismic hazard. The PSHA method (Probabilistic Seismic Hazard Assessment) has been followed, quantifying the epistemic uncertainties through a logic tree and the aleatory ones linked to variability of parameters by means of probability density functions and Monte Carlo simulations. In a first phase, the inputs have been prepared, which essentially are: 1) a project catalogue update and homogenization at Mw 2) proposal of zoning models and source characterization 3) calibration of Ground Motion Prediction Equations (GMPE’s) with actual data and development of a local model with data collected in Spain for Mw < 5.5. In a second phase, a sensitivity analysis of the different input options on hazard results has been carried out in order to have criteria for defining the branches of the logic tree and their weights. Finally, the hazard estimation was done with the logic tree shown in figure 1, including nodes for quantifying uncertainties corresponding to: 1) method for estimation of hazard (zoning and zoneless); 2) zoning models, 3) GMPE combinations used and 4) regression method for estimation of source parameters. In addition, the aleatory uncertainties corresponding to the magnitude of the events, recurrence parameters and maximum magnitude for each zone have been also considered including probability density functions and Monte Carlo simulations The main conclusions of the study are presented here, together with the obtained results in terms of PGA and other spectral accelerations SA (T) for return periods of 475, 975 and 2475 years. The map of the coefficient of variation (COV) are also represented to give an idea of the zones where the dispersion among results are the highest and the zones where the results are robust

Repair of Mitral Prolapse: Comparison of Thoracoscopic Minimally-invasive and Conventional Approaches

Objectives: Surgical repair remains the best treatment for severe primary mitral regurgitation (MR). Minimally invasive mitral valve surgery is being increasingly performed, but there is a lack of solid evidence comparing thoracoscopic with conventional surgery. Our objective was to compare outcomes of both approaches for repair of leaflet prolapse. Methods: All consecutive patients undergoing surgery for severe MR due to mitral prolapse from 2012 to 2020 were evaluated according to the approach used. Freedom from mortality, reoperation and recurrent severe MR were evaluated by Kaplan-Meier method. Differences in baseline characteristics were adjusted with propensity score-matched analysis (1:1, nearest neighbour). Results: Three hundred patients met inclusion criteria and were divided into thoracoscopic (N = 188) and conventional (sternotomy; N = 112) groups. Unmatched patients in the thoracoscopic group were younger and had lower body mass index, New York Heart Association class and EuroSCORE II preoperatively. After matching, thoracoscopic group presented significantly shorter mechanical ventilation (9 vs 15 h), shorter intensive care unit stay (41 vs 65 h) and higher postoperative haemoglobin levels (11 vs 10.2 mg/dl) despite longer bypass and cross-clamp times (+30 and +17 min). There were no differences in mortality or MR grade at discharge between groups nor differences in survival, repair failures and reinterventions during follow-up. Conclusions: Minimally invasive mitral repair can be performed in the majority of patients with mitral prolapse, without compromising outcomes, repair rate or durability, while providing shorter mechanical ventilation and intensive care unit stay and less blood loss