Thermally-activated shape memory effect on biodegradable nanocomposites based on PLA/PCL blend reinforced with hydroxyapatite

[EN] In this work, the effect of the addition of different amount of nanosized hydroxyapatite (nHA) on the shape memory behavior of blends based on poly (lactic acid) (PLA) and poly (epsilon-caprolactone) (PCL) has been studied. In particular PLA/PCL blend with 70 wt % PLA has been reinforced with 0.5, 1 and 3 wt % nHA. Moreover, the relationship between the morphology and the final properties of the nanocomposites has been investigated by field emission scanning electron microscopy, confocal Raman spectroscopy and atomic force microscopy. In particular, PeakForce has been used to study quantitative nanomechanical properties of the multifunctional materials leading to conclusion that nHA increase the phase separation between PLA and PCL as well as act as reinforcements for the PCL-rich phase of the nanocomposites. Furthermore, excellent thermally-activated shape memory response has been obtained for all the nanocomposites at 55 degrees C. Finally, the disintegration under composting conditions at laboratory scale level was studied in order to confirm the biodegradable character of these nanocomposites. Indeed, these materials are able to be used for biomedical issues as well as for packaging applications where both thermally-activated shape memory effect and biodegradability are requested.Authors thank the Spanish Ministry of Economy, Industry and Competitiveness, MINEICO, (MAT2017-88123-P) and the Regional Government of Madrid (S2013/MIT-2862) for the economic support. M.P.A. and L.P. acknowledge the Juan de la Cierva (FJCI-2014-20630) and Ramon y Cajal (RYC-2014-15595) contracts from the MINEICO, respectively. The authors also thanks CSIC for the I-Link project (I-Link1149).Peponi, L.; Sessini, V.; Arrieta, MP.; Navarro-Baena, I.; Sonseca Olalla, Á.; Dominici, F.; Giménez Torres, E.... (2018). Thermally-activated shape memory effect on biodegradable nanocomposites based on PLA/PCL blend reinforced with hydroxyapatite. Polymer Degradation and Stability. 151:36-51. https://doi.org/10.1016/j.polymdegradstab.2018.02.019S365115

Multilatinas: Financial performance and speed of international expansion

The phenomenon of Multilatinas companies has aroused the interest of numerous investigations in recent years. In particular, it has been studied why and under what conditions these organizations expand. However, the implications of financial performance conditions on the speed of international expansion of these types of companies still require further clarification and explanation. The objective of this paper is to analyze the speed of internationalization of multilatinas companies and the financial performance factors that affect their international expansion. For this, econometric analysis is carried out, using as dependent variable the speed of international expansion, measured as a ratio of companies’ foreign direct investment (FDI) and sales. As explanatory variables, the financial indicators of profitability, indebtedness and leverage are used. By this, it is possible to identify the relationship between financial performance and the rate at which companies grow in international markets. The size of the company, the economic sectors and the countries of origin of the companies are used as control variables. Results show that profitability and indebtedness have positive effects on the speed of internationalization; as well leverage with certain restrictions

Multilatinas: Desempeño financiero y velocidad de expansión internacional

The phenomenon of Multilatinas companies has aroused the interest of numerous investigations in recent years. In particular, it has been studied why and under what conditions these organizations expand. However, the implications of financial performance conditions on the speed of international expansion of these types of companies still require further clarification and explanation. The objective of this paper is to analyze the speed of internationalization of multilatinas companies and the financial performance factors that affect their international expansion. For this, econometric analysis is carried out, using as dependent variable the speed of international expansion, measured as a ratio of companies’ foreign direct investment (FDI) and sales. As explanatory variables, the financial indicators of profitability, indebtedness and leverage are used. By this, it is possible to identify the relationship between financial performance and the rate at which companies grow in international markets. The size of the company, the economic sectors and the countries of origin of the companies are used as control variables. Results show that profitability and indebtedness have positive effects on the speed of internationalization; as well leverage with certain restrictions.El fenómeno de las empresas Multilatinas ha despertado el interés de numerosas investigaciones en los años recientes. En particular se ha estudiado porqué y en qué condiciones se expanden estas organizaciones. Sin embargo, las implicaciones de las condiciones de desempeño financiero en la velocidad de expansión internacional de este tipo de empresas aún requieren mayor clarificación y explicación. El objetivo de este trabajo es analizar la velocidad de internacionalización de las empresas multilatinas y los factores de desempeño financiero que inciden en su crecimiento internacional. Para esto, el trabajo aplica un modelo de análisis econométrico, usando como variable dependiente la velocidad de expansión internacional, definida como la ratio entre el promedio de la inversión extranjera directa (IED) de las empresas y su volumen de ventas. Como variables independientes se emplean las variables de rentabilidad, endeudamiento y apalancamiento. De esta manera, se busca identificar la relación entre los principales indicadores de desempeño financiero y la tasa a la cual crecen las empresas en los mercados internacionales. Se utilizan como variables de control el tamaño de la empresa, los sectores económicos y los países de origen de las empresas. Los resultados evidencian que las variables rentabilidad y endeudamiento guardan relación con la dinámica de la velocidad de internacionalización de las empresas analizadas, asimismo la variable apalancamiento logra explicarla con ciertas restricciones

La importancia del diagnóstico estratégico en las organizaciones

The strategic diagnosis is carried out in all companies, to know how to evaluate the situation of the organization, which includes the analysis inside and outside the organization, that is, internal and external. The success of organizations results from the execution of appropriate strategies and thus avoid wasting time and resources on unnecessary strategies for their market sector. The diagnosis is carried out in order to identify the opportunities, threats, strengths and weaknesses of the organization. As the main objective we will identify the important aspects that an organization must consider carrying out a strategic diagnosis and thus determine the importance of this. The methodology to be used consists of research in the different authors who provide us with relevant information with our approach to carry out the test and in this way reach as a team the conclusions of the importance of strategic diagnosis in organizations.El diagnostico estratégico se realiza en todas las empresas, para saber evaluar la situación de la organización, lo cual incluye el análisis dentro y fuera de la organización, es decir interno y externo. El éxito de las organizaciones resulta de la ejecución de estrategias adecuadas y así evitar gastar tiempo, recursos en estrategias innecesarias para su sector de mercado. El diagnostico se realiza con la finalidad de identificar las oportunidades, amenazas, fortalezas y debilidades de la organización. Como objetivo principal identificaremos los aspectos importantes que debe tener en cuenta una organización para realizar un diagnóstico estratégico y de esta manera determinar la importancia de este. La metodología para utilizar consta de investigación en los diferentes autores que nos aporten información relevante con nuestro enfoque para realizar el ensayo y de esta manera llegar como equipo a las conclusiones de la importancia del diagnóstico estratégico en las organizaciones

The importance of the strategic diagnostic in organizations

El diagnostico estratégico se realiza en todas las empresas, para saber evaluar la situación de la organización, lo cual incluye el análisis dentro y fuera de la organización, es decir interno y externo. El éxito de las organizaciones resulta de la ejecución de estrategias adecuadas y así evitar gastar tiempo, recursos en estrategias innecesarias para su sector de mercado. El diagnostico se realiza con la finalidad de identificar las oportunidades, amenazas, fortalezas y debilidades de la organización. Como objetivo principal identificaremos los aspectos importantes que debe tener en cuenta una organización para realizar un diagnóstico estratégico y de esta manera determinar la importancia de este. La metodología para utilizar consta de investigación en los diferentes autores que nos aporten información relevante con nuestro enfoque para realizar el ensayo y de esta manera llegar como equipo a las conclusiones de la importancia del diagnóstico estratégico en las organizaciones.The strategic diagnosis is carried out in all companies, to know how to evaluate the situation of the organization, which includes the analysis inside and outside the organization, that is, internal and external. The success of organizations results from the execution of appropriate strategies and thus avoid wasting time and resources on unnecessary strategies for their market sector. The diagnosis is carried out in order to identify the opportunities, threats, strengths and weaknesses of the organization. As the main objective we will identify the important aspects that an organization must consider carrying out a strategic diagnosis and thus determine the importance of this. The methodology to be used consists of research in the different authors who provide us with relevant information with our approach to carry out the test and in this way reach as a team the conclusions of the importance of strategic diagnosis in organizations

La enfermedad de Chagas y sus repercusiones en la salud de los pacientes en Latinoamérica

El objetivo de la presente revisión es describir las principales implicaciones de la enfermedad de Chagas en la salud pública e individual de los pacientes latinoamericanos con el propósito de integrar información relevante y aportar un conocimiento significativo sobre dicha temática. Se realizó una monografía de compilación sistematizada en la cual se integran conocimientos provenientes de fuentes como artículos de revisión bibliográfica, textos guías, consensos y artículos científicos. Se evidencia que la enfermedad de Chagas es un problema de salud pública que genera elevados costos y afecta principalmente a poblaciones de bajos recursos y áreas rurales. Además, tiene un gran impacto en la salud individual, provocando afecciones como la miocardiopatía, cuyas manifestaciones tempranas son alteraciones asintomáticas en el ecocardiograma y anormalidades de la conducción, mientras que, en etapas finales se presentan alteraciones propias de la miocardiopatía dilatada. Por otro lado, un porcentaje de pacientes chagásicos desarrolla complicaciones digestivas como el megacolon y megaesófago, debido a una alteración del sistema nervioso entérico que genera úlceras, constipación crónica y aumento del tiempo del tránsito esofágico, entre otras. Se encontró una asociación entre la miocardiopatía chagásica y el síndrome metabólico, dado que esta última produce alteraciones inmunitarias y endocrinas, que podrían ser factores importantes en el desarrollo de la patología cardiaca y, adicionalmente, varios estudios demuestran una mayor prevalencia de síndrome metabólico y de sus componentes en individuos con Chagas crónico. Sin embargo, aún se requieren estudios con una mayor potencia estadística que comprueben una relación causal.PregradoMedic

Diseño de un árbol solar para la seccional del Bajo Cauca de la Universidad de Antioquia

En este trabajo se presenta el diseño conceptual y de detalle de una estructura de metal que asemeja un árbol real con ramas, en cuya parte superior se ubican paneles solares fotovoltaicos. La energía generada será usada para cargar baterías de móviles, tabletas y computadoras portátiles de la comunidad universitaria de la seccional del Bajo Cauca de la Universidad de Antioquia, localizada en las coordenadas de latitud 7,990584° y longitud −75,193100°. Para el diseño del árbol, inicialmente, se realizó una estimación del recurso solar en la seccional, por lo que se estableció que el promedio anual de las horas solar pico fue equivalente a 18,74 MJ/m2. Con base en un requerimiento energético diario de 1400 Wh/día, se determinó que el número de paneles a instalarse de 180 Wp es de 2. La estructura del árbol fue analizada numéricamente utilizando un software de elementos finitos con el fin de determinar las tensiones y deformaciones debidas a las cargas externas y a su propio peso para garantizar su integridad estructural. El diseño presentado constituye una estructura portátil que puede producir energía verde y proporcionar un lugar de encuentro en la seccional del Bajo Cauca.The conceptual and detailed design of a metal structure resembling a real tree with branches, in whose upper part photovoltaic solar panels are located, is presented in this work. The energy generated will be used to charge batteries for mobile phones, tablets and laptops belonging to the university community in Bajo Cauca headquarter of Universidad de Antioquia, located at a latitude of 7.990584° and a longitude of -75.193100°. For the design of the tree, an estimation of the solar resource in the headquarter was initially conducted; it was established that the annual average of peak solar hours was equivalent to 18.74 MJ/m2. Based on a daily energy requirement of 1400 Wh/day, the number of 180 Wp panels to be installed was determined to be 2. The tree structure was numerically analyzed using a finite element software in order to determine the stresses and deformations due to external loads and its own weight to guarantee its structural integrity. The featured design is a portable structure that can produce green energy and provide a meeting place at the Bajo Cauca headquarter

Organizational culture and innovation in a national context. Comparison of online companies in Russia and Finland

Innovation is essential for companies to stay competitive and achieve good performance. To drive innovation, it is important to create an organizational culture supportive of innovation. However, since organizational culture is affected by national values of employees, organizational culture that drives innovation might vary in different national contexts. To investigate this issue, eight online companies, four in Russia and four in Finland, were studied using semi-structured interviews. Results of the study demonstrate that online companies in Russia consider involvement and adaptability culture traits, particularly empowerment, capability development, tolerance of mistakes and creating change subtraits, as most important for facilitating innovation. National culture of Russia enforces relationship between involvement trait and innovation, but imposes challenges in terms of adaptability trait. In Finland, involvement and adaptability are also considered as most important, but most important subtraits are slightly different including empowerment, tolerance of mistakes, feedback and team orientation. National culture of Finland facilitates easier adoption of empowerment, but imposes some challenges for enabling tolerance of mistakes. The conclusion is that national culture enforces positive relationship between organizational culture trait and innovation, when organizational and national culture are aligned, and imposes challenges, when national culture contradicts organizational one. This study offers insight on organizational culture traits that drive innovation in a national context of Russia and Finland as well as on factors – culture communication and culture strength - that ensure effective implementation of innovation supportive culture. The study also suggests innovation orientation as one of the important consideration in developing innovation supportive organizational culture