Efectos del sistema multifondos en el Régimen de Ahorro Individual en Colombia

RESUMEN:Con el fin de analizar los posibles efectos de una reforma financiera dirigida a flexibilizar la regulación de los Fondos de Pensiones en Colombia, estedocumento evalúa los potenciales efectos de esta reforma sobre el bienestar delos agentes, aplicando el supuesto de individuos con funciones de utilidad conaversión absoluta al riesgo constante (CARA) y la Teoría de Diversificación del Portafolio. Adicionalmente se presenta un ejercicio contrafactual para estimar el valor del activo pensional si los principios de esta legislación hubiesen sido aplicados en el periodo 1980-2009. Los resultados del análisis teórico sugieren que ante un mayor valor acumulado en las cuentas de pensión, los individuos disminuyen su exposición ante el riesgo en sus portafolios. Mientras que el ejercicio contrafactual indica que la mejor decisión para los individuos habría sido invertir todo el portafolio en activos de renta variable.ABSTRACT:In order to analyze the potencial effects of a financial reform aimed to provide more flexibility to Colombian Pension Funds´ regulation, this documenttheoretically evaluates the effects of this reform over agents´ welfare, by applying the Constant Absolute Risk Aversion (CARA) assumption and Modern Portfolio (Diversification) Theory. An empirical counterfactual exercise is used to estimate the value of pension personal account´s on the case that the foundations of this financial reform happen to be present between 1980 and 2009. Theoretical analysis suggests that individuals decrease their risk exposition according to an increase in the accumulated value in their personalaccounts. In contrast, counterfactual´s exercise conclusion is that the bestchoice for individuals would have been to invest the whole portfolio in variable rent assets.Sistema de pensiones, sistema multifondos, Teoríaa de Diversificación del portafolio, función de utilidad CARA.

Efecto de la pre-inmunización con vectores adenovirales sobre la efectividad terapéutica y la toxicidad de la terapia génica antitumoral

Tesis (Doctorado en Ciencias con Especialidad en Biología Molecular e Ingeniería Genética) UANLUANLhttp://www.uanl.mx

Modelo computacional para la formación de clases de equivalencia

A computational model of neuronal net closely related with the formation of equivalence classes is developed. First the formal pattern of the neuronal net is presented and then its operation and its direct relationship with the phenomenon of the formation of the equivalence classes and with the derived relationships are explained. Later on, the validation of the pattern is described carrying out several simulations allowing verification of the pattern so it is able to generate relationships not explicitly trained, these results being adjusted to the basic results of this investigation line. These simulations were carried out using a training of classic conditioning and a test phase by means of conditional discriminations

Adecuación tecnológica de la máquina de inyección de plástico del laboratorio de mecánica, de la Universidad Tecnológica de Pereira

Este proyecto muestra la adecuación tecnológica de la máquina de inyección de plástico del laboratorio de mecánica de la Universidad Tecnológica de Pereira. Como parte inicial del trabajo realizado se muestran los diferentes diseños de hardware electrónico de tal manera que la adecuación realizada trabaje en conjunto y de manera paralela a los dispositivos eléctricos ya instalados. Dentro de los dispositivos instalados se cuenta con software de Supervisión, Control y Adquisición de Datos (Supervisory Control And Data Acquisition) SCADA el cual interactúa con la máquina a través de una comunicación serial con un controlador lógico programable S7-200 Siemens este dispositivo es el intermediario entre el SCADA y las diferentes variables del proceso de modelado de plástico. El sistema SCADA Registra las temperaturas del tubo de plastificación, permite ajustar el Set Point de temperatura requeridos, tiempos asociados al proceso de plastificación, además permite seleccionar el modo de operación de la máquina entre manual y automático, también se puede ajustar el número de ciclos en el modo de operación automática.This project shows the technological adequacy of plastic injection machine, of the mechanics laboratory in the Technological University of Pereira. As initial part of this work, shows the different designs of electronic hardware so that the adequacy carried out work as a whole and in parallel with the electric and electronic devices already installed. inside the new installed devices, is provided with a control software and supervision called SCADA, which interacts with the machine through a direct communication with a programmable logical controller S7200; this device is the intermediary between the SCADA and the different variables associated with the process of molded of plastic pieces. The SCADA system recorded the temperatures of the plasticizing tube; allows you to adjust the temperature set points required; times associated with the process of plasticizing; also allows you to select the command of operation of the machine between manual and automatic, as final quality you can adjust the number of repetitions cyclical in the automatic operating mode

El saneamiento de la falsa tradición y la titulación de la posesión material de bienes inmuebles rurales en vigencia de la Ley 1561 de 2012, a la luz de la garantía de tutela judicial efectiva en Colombia

155 páginasEl saneamiento de la falsa tradición bajo los lineamientos de la Ley 1561 de 2012, se analiza a partir del registro público inmobiliario, para establecer vulneraciones a la tutela judicial efectiva, en instancia judicial y administrativa, en relación a inmuebles rurales. Se estudia el valor probatorio del certificado especial, resaltándose el certificado negativo expuesto en la sentencia T-383 de 2000 de la Corte Constitucional, el cual también fue afectado por el Decreto 578 de 2018. Se parte para tal efecto, de una diferenciación entre la inexistencia plena de antecedentes registra les de los predios, y el nacimiento jurídico en falsa tradición, exponiendo la principal jurisprudencia surgida desde la sentencia T-488 de 2014 de la Corte Constitucional. La tutela judicial efectiva se vio desde el derecho de acceso al proceso y a su desarrollo, el derecho a obtener una sentencia de fondo, y el derecho a la ejecución y cumplimiento de esta, todo esto, frente al juzgado de conocimiento y la oficina de registro de instrumentos públicos respectiva.The sanitation of the false transfer in trust under the guidelines of Law 1561 of 2012, is analyzed from the public real estate registry, to establishing infrigements of the right to effective legal protection, in judicial and administrative instances, regarded to rural real estate. The probative value of the special certificate is studied, highlighting the negative certificate set forth in judgment T-383 of 2000 of the Constitutional Court, which was also affected by Decree 578 of 2018. For this purpose, it is based on a differentiation between the lack of full registration of land, and the legal birth in a false transfer in trust, exposing the main jurisprudence that has emerged since judgment T-488 of 2014 of the Constitutional Court. The effective legal protection was seen from the right of access to the process and its development, the right to obtain a substantive sentence, and the right to the execution and enforcement with it, all this, related to the court of knowledge and the respective public document registration office.Magíster en Justicia y Tutela de los Derechos con énfasis en Derecho ProcesalMaestrí

Evaluation of a Bayesian Algorithm to Detect Burned Areas in the Canary Islands’ Dry Woodlands and Forests Ecoregion Using MODIS Data

Burned Area (BA) is deemed as a primary variable to understand the Earth’s climate system. Satellite remote sensing data have allowed for the development of various burned area detection algorithms that have been globally applied to and assessed in diverse ecosystems, ranging from tropical to boreal. In this paper, we present a Bayesian algorithm (BY-MODIS) that detects burned areas in a time series of Moderate Resolution Imaging Spectroradiometer (MODIS) images from 2002 to 2012 of the Canary Islands’ dry woodlands and forests ecoregion (Spain). Based on daily image products MODIS, MOD09GQ (250 m), and MOD11A1 (1 km), the surface spectral reflectance and the land surface temperature, respectively, 10 day composites were built using the maximum temperature criterion. Variables used in BY-MODIS were the Global Environment Monitoring Index (GEMI) and Burn Boreal Forest Index (BBFI), alongside the NIR spectral band, all of which refer to the previous year and the year the fire took place in. Reference polygons for the 14 fires exceeding 100 hectares and identified within the period under analysis were developed using both post-fire LANDSAT images and official information from the forest fires national database by the Ministry of Agriculture and Fisheries, Food and Environment of Spain (MAPAMA). The results obtained by BY-MODIS can be compared to those by official burned area products, MCD45A1 and MCD64A1. Despite that the best overall results correspond to MCD64A1, BY-MODIS proved to be an alternative for burned area mapping in the Canary Islands, a region with a great topographic complexity and diverse types of ecosystems. The total burned area detected by the BY-MODIS classifier was 64.9% of the MAPAMA reference data, and 78.6% according to data obtained from the LANDSAT images, with the lowest average commission error (11%) out of the three products and a correlation (R2) of 0.82. The Bayesian algorithm—originally developed to detect burned areas in North American boreal forests using AVHRR archival data Long-Term Data Record—can be successfully applied to a lower latitude forest ecosystem totally different from the boreal ecosystem and using daily time series of satellite images from MODIS with a 250 m spatial resolution, as long as a set of training areas adequately characterising the dynamics of the forest canopy affected by the fire is defined

Correlation between Mn oxidation state and magnetic behavior in Mn/ZnO multilayers prepared by sputtering

Compositional, microstructural, and magnetic characterization of ZnO 30 Å/Mn x n multilayers prepared by sputtering is presented to study the observed ferromagnetism in the Mn-ZnO system. The nominal Mn layer thickness, x, is varied from 3 to 60 Å, while the number of bilayers, n, is increased to maintain the total amount of Mn constant. Microstructure information was deduced from x-ray reflectivity, Mn oxidation state was determined by x-ray absorption spectroscopy, and magnetic properties were measured over a temperature range of 5–400 K. Magnetic behavior of these samples is found to be related to the Mn layer thickness x. Multilayers with x 30 Å exhibit ferromagnetism with a Curie temperature above 400 K, while mostly paramagnetic behavior is obtained for x15 Å. Magnetic behavior is discussed in terms of electronic and structural parameters of samples. Mn-ZnO interface effect is related to the ferromagnetic order of the samples, but it is not a sufficient condition. The essential role of the Mn oxidation state in the magnetic behavior of this system is pointed out. It is shown a correlation between the obtained ferromagnetism and a Mn oxidation state close to 2+.Ministerio de Educación y Ciencias de España-MAT2003-01880 y MAT2006-0100

Estudio del efecto en las propiedades mecánicas del concreto simple reforzado con fibras de tereftalato de polietileno (PET) y polipropileno (PP)

En este estudio, se evaluaron propiedades físicas y mecánicas de fibras de tereftalato de polietileno (PET) y polipropileno (PP), a través de determinación de la densidad y ensayos de tensión acorde a la norma ASTM D882 (2012). Encontrando que las fibras de PET presentaron una mayor relación resistencia peso que el PP. Posteriormente, se realizó un diseño de mezcla de concreto para una resistencia última de 17.23 MPa, y se adicionó fibras de PET y PP, reemplazando porcentajes en volumen de 0.5; 1.0; 1.5 y 2.0 % sobre el volumen total del agregado fino, con el fin de analizar el efecto que tiene la adición de fibras en la resistencia a compresión y parámetros mecánicos de flexión para muestras con una edad de curado de 3, 7 y 28 días, de acuerdo a las normas ASTM C39/C39M (2014) y ASTM C293(2016) respectivamente, con el propósito de compararlas con muestras sin adición de fibra. Luego de los ensayos de compresión, se encontró que a mayor porcentaje de fibra adicionada a la mezcla de concreto, la resistencia a compresión disminuía, obteniendo la menor caída de resistencia a compresión para el grupo de muestras con adición de fibra de 0.5 % de PET y 0.5 % de PP. Asimismo, después de los ensayos de flexión a tres puntos, se encontró que las muestras con 0.5 % de fibras de PET y 0.5 % de fibras de PP registraron las menores caídas en el valor de carga de rotura y módulo de elasticidad en flexión. Finalmente, se observó que la presencia de fibras en la matriz de concreto, ayuda a mantenerla unida después de ocurrida la falla.Pregrad

"La prohibición de inscripción de acciones en el mercado público de valores : justificación jurídica y práctica en las sociedades por acciones simplificadas"

Abogado (a)Pregrad

Material-driven fibronectin assembly for high-efficiency presentation of growth factors

Growth factors (GFs) are powerful signaling molecules with the potential to drive regenerative strategies, including bone repair and vascularization. However, GFs are typically delivered in soluble format at supraphysiological doses because of rapid clearance and limited therapeutic impact. These high doses have serious side effects and are expensive. Although it is well established that GF interactions with extracellular matrix proteins such as fibronectin control GF presentation and activity, a translation-ready approach to unlocking GF potential has not been realized. We demonstrate a simple, robust, and controlled material-based approach to enhance the activity of GFs during tissue healing. The underlying mechanism is based on spontaneous fibrillar organization of fibronectin driven by adsorption onto the polymer poly(ethyl acrylate). Fibrillar fibronectin on this polymer, but not a globular conformation obtained on control polymers, promotes synergistic presentation of integrin-binding sites and bound bone morphogenetic protein 2 (BMP-2), which enhances mesenchymal stem cell osteogenesis in vitro and drives full regeneration of a nonhealing bone defect in vivo at low GF concentrations. This simple and translatable technology could unlock the full regenerative potential of GF therapies while improving safety and cost-effectiveness