Resumen Con base en la Teoría de Dependencia de Recursos (TDR) y la Teoría de Agencia (TA), esta investigación tiene por objetivo analizar si existe una relación entre el número y tipo de consejeros (constructo consejo de administración) con respecto a indicadores de desempeño financiero de la empresa con base en ROA, ROE, Margen de Beneficio Neto, ingresos por empleado y riesgo sistemático de mercado-beta (constructo desempeño financiero). Utilizando el método innovador y adecuado para muestras pequeñas PLS-SEM, se crea un modelo teórico basado en la revisión de literatura y un modelo de medición que opera con base en correlaciones múltiples y simultáneas entre las variables seleccionadas. Los resultados muestran la conformación de dos constructos y denotan una relación estadísticamente significativa entre ambos. Se tiene la limitante de ser un análisis exploratorio y transversal. El estudio es original en la aplicación del método estadístico al campo del gobierno corporativo y las finanzas y en la selección de variables. Se concluye que el modelo teórico planteado es eficiente para continuar estudiando los constructos en las empresas.

Abstract Based on the Resource Dependence Theory (TDR) and the Agency Theory (TA), this research aims to analyze whether there is a relationship between the number and type of directors (construct board of directors) concerning indicators of financial performance of the company based on ROA, ROE, Net Profit Margin, Income Per Employee, and Beta or Systematic Risk (construct financial performance). Using the innovative and suitable method for small samples, PLS-SEM, authors create a theoretical model based on literature review and a measurement model that operates based on multiple and simultaneous correlations between the selected variables. The results show the conformation of two constructs and denote a statistically significant relationship between them. It has the limitation of being an exploratory and transversal analysis. The study is original in applying the statistical method to the field of corporate governance and finance and in the selection of variables. It is concluded that the proposed theoretical model is efficient in studying the constructs in companies.

Abstract Per capita meat consumption in Chile is 89.1 kg per year in 2014, of which approximately 25 kg are beef. Some 50% of the beef consumed is imported as vacuum packaged meat from two species, Bos taurus, produced mainly in Chile, Argentina and Paraguay, and Bos indicus, which comes mainly from Brazil and Paraguay. The latter two countries account for the highest levels of beef imports in Chile. The objective of this investigation was to study and compare the fatty acid profiles of beef from Bos Taurus from Chile and Bos indicus from Paraguay and Brazil. Samples of vacuum packaged Longissimus dorsi muscle tissue were collected from private companies, two Chilean, three Paraguayan and two Brazilian. The fatty acid profiles were determined by GLC according to standardized regulations. There were differences in the fat profiles of the analyzed meats, mainly in the content of saturated and monounsaturated fatty acids. Brazilian and Paraguayan beef had similar fat compositions, with higher saturated fat content and lower monounsaturated fat content than the Chilean beef. The saturated and monounsaturated fat contents in the Chilean beef were similar. All the analyzed beef samples had a low content of trans and polyunsaturated fats.

Background and Objective It is a fact that Plastic Surgery is the most artistic specialty in Medicine and even though Reconstructive Surgery and Aesthetic Surgery constitute it, there is no limit between them. One of the techniques that we mostly perform within the specialty is rhinoplasty and in the same way, although dogmatically there are differences between an aesthetic rhinoplasty and a reconstructive or functional rhinoplasty, both can benefit from the same management. Some procedures used with good results in the repair of congenital malformations or acquired deformities, can be used in patients whose nasal morphology is normal and for cosmetic purposes only. Methods In order to describe the function of reconstructive rhinoplasty procedures applied to aesthetic rhinoplasty, a review of reconstructive surgical procedures that can be applied according to the aesthetics subunits was carried out, highlighting those performed on the dorsum, the lateral walls and the tip, explaining how cartilages or composite grafts are used. Results These techniques accumulate the experience of the last 18 years of the main author with the management of nasal surgery, both in the reconstructive and aesthetic field. It is important to consider that the selection of patients and the preoperative analysis will always be an invaluable tool to achieve a good result. Conclusions The integration of reconstructive surgery procedures applied in the aesthetic surgery of the nose can provide optimal results in different types of patients, previously selected.

Resumen Introducción y Objetivo Es un hecho que la Cirugía Plástica es la parte más artística de la Medicina, y aunque está constituida por la Cirugía Reconstructiva y la Cirugía Estética, no existe un límite entre ambas. Una de las técnicas que mayormente realizamos dentro de nuestra especialidad es la rinoplastia, y de la misma manera, aunque dogmáticamente existen diferencias entre una rinoplastia estética y una reconstructiva o funcional, ambas pueden beneficiarse del mismo manejo. Algunos procedimientos empleados con buen resultado en la reparación de deformidades congénitas o adquiridas, pueden utilizarse en pacientes cuya morfología nasal es normal, sólo con fines estéticos. Material y método Realizamos una revisión de los procedimientos quirúrgicos reconstructivos nasales que pueden aplicarse de acuerdo a las subunidades estéticas, destacando los realizados en dorso, paredes laterales y punta, explicando el cómo y porqué del uso de injertos cartilaginosos o compuestos. Resultados Dichas técnicas acumulan la experiencia de los últimos 18 años del autor principal en cirugía nasal, tanto reconstructiva como estética. Es importante hacer notar que la correcta selección de los pacientes y el análisis preoperatorio serán siempre un instrumento valioso para lograr un buen resultado. Conclusiones La integración de procedimientos propios de la Cirugía Reconstructiva aplicados en la Cirugía Estética de la nariz, pueden proporcionar resultados óptimos en diferentes tipos de pacientes previamente seleccionados.

Abstract This paper presents the results of the analysis of the Mexican stock market to find if implicit volatility could be used as a systematic determinant in order to explain the yields of ten of the most representative stocks in the Mexican market. We applied statistical methods and regression techniques to explore if there is any relationship between Mexican VIX or VIMEX and historical returns of the IPC. We observed that there is a negative correlation between implicit volatility and stock returns, and tested if VIMEX could be used as an alternative method to explain systematic risk.

Resumen En este artículo se presentan los resultados del estudio sobre el mercado de valores de México para determinar si la volatilidad implícita puede utilizarse como una determinante sistemática para poder explicar los rendimientos de las diez acciones con mayor bursatilidad en el mercado mexicano. Se aplicaron métodos estadísticos y técnicas de regresión para explorar si existe alguna relación entre el VIX mexicano o VIMEX y los rendimientos históricos del Índice de Precios y Cotizaciones, IPC. Los resultados obtenidos confirman que existe una correlación negativa entre la volatilidad implícita y los rendimientos de las acciones, y se comprobó que el VIMEX puede usarse como un método alternativo para explicar el riesgo sistemático.

Gelatin, chitosan and hyaluronic acid are natural components used to prepare polymeric scaffold in tissue engineering. The physical properties of these materials confer an appropriate microenvironment for cells, which can be used as a regeneration system for skin and cartilage. In this work, we prepared and characterized a Gelatin/Chitosan/Hyaluronan lyophilized-polymer. Physical properties of lyophilized-polymer changed slightly with moisture, but when polymer was totally hydrated the elasticity changed significantly. Thermophysical characterisation indicated that temperatures higher than 30ºC could modify irreversibly the polymeric matrix probably due to protein denaturation. Besides, we used the polymer as scaffold to prepare a biosynthetic-skin, reporting biological behaviour and its mechanical properties.

Dendritic cells (DC) are considered the most important antigen presenting cells of the immune system. Its anatomical location (skin, mucosa and peripheral blood), the expression of receptors to recognize pathogens, the expression of co-stimulatory molecules (CD80/86), the major histocompatibility complex (MHC) class I and II, and the production of cytokines (such as IFN-α, IL-10, IL-12) confers to these cells the characteristic to regulate innate and adaptive immune responses. The objective of this work was to evaluate the effects of the porcine reproductive and respiratory virus (PRRS) in mature DC. DC were generated from blood monocytes using IL-4 and GM-CSF and were stimulated with lipopolysaccharide (LPS) to induce their maturation. The results show that the expression of CD14 and CD172a molecules in infected DC was not affected, while MHC II and CD80/86 expression was diminished. This decrease seems to affect the allogenic proliferation of lymphocytes stimulated with infected DC. On the other hand, the virus increases mRNA expression of IL-10 and TNF-α, and diminishes that for IL-1 β and IL-6. The results obtained could explain, in part, the immunophatology of the disease.

Las células dendríticas (DC) son las presentadoras de antígeno más importantes del sistema inmune. Su localización anatómica (piel, mucosas y sangre periférica), la expresión de receptores para reconocer patógenos, la expresión de moléculas de coestimulación (CD80/86), del complejo principal de histocompatibilidad (MHC) clases I y II, y la producción de citocinas (IFN-α, IL-10, IL-12), les confiere una característica única para regular las respuestas inmune innata y adaptativa. El objetivo de este trabajo fue evaluar el efecto del virus de síndrome reproductivo y respiratorio porcino (PRRS) en DC maduras. Se generaron células dendríticas a partir de monocitos utilizando IL-4 y GM-CSF y se estimularon con lipopolisacárido (LPS) para inducir su maduración. Los resultados muestran que la expresión de las moléculas CD14 y CD172a no se altera en las DC infectadas, mientras que la expresión de MHC II y CD80/86 se ve disminuida. Esta disminución parece afectar la proliferación alogénica de linfocitos estimulados con DC infectadas. Asimismo, el virus aumenta la expresión del ARNm de IL-10 y TNF-α, y disminuye la de IL-1 β e IL-6. Lo anterior explica, en parte, la inmunopatología de la enfermedad.