Temporada reproductiva y densidad poblacional en tres especies de aves de la familia Thamnophilidae del bosque seco tropical en el departamento del Tolima

58 P?ginasRecurso Electr?nicoLas especies Thamnophilus doliatus, Formicivora grisea y Myrmeciza longipes han sido registradas en el departamento del Tolima, asociadas a vegetaci?n en regeneraci?n, bosques secundarios y bordes de bosque en la zona de vida Bosque Seco Tropical (bs-T). Sin embargo, existe un vac?o de informaci?n en los periodos reproductivos y la estimaci?n demogr?fica en la regi?n. El objetivo de este estudio fue establecer la temporalidad reproductiva y la densidad poblacional de estas especies en el bs-T. Fueron consultadas las bases de datos del Programa de Monitoreo de Aves en Armero-Guayabal del periodo 2010-2013, registrando los estados reproductivos, comparando la fecha de los datos con las precipitaciones para determinar la temporalidad reproductiva. Se llevaron a cabo transectos en tres localidades (Armero-Guayabal, Potrerillo y Chaco) para estimar la densidad poblacional y relacionarlo con diferentes componentes del paisaje. Se encontr? mayor abundancia de individuos reproductivos de T. doliatus y F. grisea en abril-marzo (lluvias). La densidad global promedio de T. doliatus (0,53 Ind/Ha) fue mayor a M. longipes (0,23 Ind/Ha); en lluvias se present? densidades altas para T. doliatus en Armero-Guayabal (0,783 Ind/Ha) y Chaco (0,261 Ind/Ha), sequ?a para M. longipes en Armero-Guayabal (0,319 Ind/Ha); no se hall? relaci?n con los elementos del paisaje y la densidad. En conclusi?n, los picos reproductivos de T. doliatus y F. grisea se asociaron con las precipitaciones. La especie T. doliatus registr? la mayor densidad promedio global, encontrando que la densidad de T. doliatus y M. longipes vari? en diferentes ?pocas clim?ticas en los tres sitios de estudio.ABSTRACT. Thamnophilus doliatus, Formicivora grisea and Myrmeciza longipes species have been recorded in the department of Tolima, associated with regenerating vegetation, secondary forests and forest edges in the life zone Tropical Dry Forest life (bs-T). However, there is an information gap about reproductive periods and population estimates in the region. The aim of this study was to establish the reproductive seasonality and population density of these species in the bs-T. Databases were consulted of Bird Monitoring Program in Armero-Guayabal period 2010-2013, recording the reproductive stages, comparing rainfall data to determine reproductive seasonality. Transects were conducted at three locations (Armero-Guayabal, Potrerillo and Chaco) to estimate the population density and relate different components of the landscape. Greater abundance of reproductive individuals of T. doliatus and F. grisea in March-April (rains) was found. The average overall density of T. doliatus (0.53 Ind/ha) was higher than M. longipes (0.23 Ind/ha); rains for high densities in T. doliatus in Armero-Guayabal (0.783 Ind/ha) and Chaco (0.261 Ind/ha), drought in M. longipes Armero-Guayabal (0.319 Ind/ha) was presented; not related to landscape elements and the density was found. In conclusion, reproductive peaks T. doliatus and F. grisea associated with precipitation. T. doliatus species the highest total average density, find the density of T. doliatus and M. longipes varied in different climatic seasons in the three study sites.INTRODUCCI?N 13 1. OBJETIVOS 15 1.1 OBJETIVO GENERAL 15 1.2 OBJETIVOS ESPEC?FICOS 15 2. MARCO TEORICO 16 2.1 MARCO REFERENCIAL 16 2.1.1 Estrategias de vida y reproducci?n de aves Neotropicales 16 2.1.2 Densidad poblacional en aves 17 2.1.3 Especies focales del estudio 18 2.2 ANTECEDENTES 20 2.2.1 Thamnophilus doliatus (Linnaeus, 1764) 22 2.2.2 Myrmeciza longipes (Swainson, 1825) 22 2.2.3 Formicivora grisea (Boddaert, 1783) 23 3. METODOLOG?A 24 3.1 ?REA DE ESTUDIO 24 3.1.1 Localizaci?n geogr?fica 24 3.1.2 Sitios de muestreo 24 3.1.3 Variable ambiental 27 3.2 FASE DE CAMPO 28 3.2.1 Estado reproductivo 28 3.2.2 Densidad poblacional 29 3.3 ANALISIS DE DATOS 31 3.3.1 Temporada reproductiva 31 3.3.2 Densidad poblacional 31 3.3.3 An?lisis de paisaje 32 4. RESULTADOS 34 4.1 TEMPORADA REPRODUCTIVA 34 4.2 DENSIDAD POBLACIONAL 36 5. DISCUSI?N 41 5.1 TEMPORADA REPRODUCTIVA 41 5.2 DENSIDAD POBLACIONAL 42 5.3 CONSIDERACIONES FINALES 45 6. CONCLUSIONES 46 7. RECOMENDACIONES 47 REFERENCIAS 4

Finite-dimensional pointed Hopf algebras over finite simple groups of Lie type II. Unipotent classes in the symplectic groups

We show that Nichols algebras of most simple Yetter-Drin-feld modules over the projective symplectic linear group over a finite field, corresponding to unipotent orbits, have infinite dimension. We give a criterium to deal with unipotent classes of general finite simple groups of Lie type and apply it to regular classes in Chevalley and Steinberg groups

Captura de carbono en ra?ces finas y estructurales en bosques alto-andinos y sistemas agroforestales en asocio con ?rboles dispersos y cultivos en Santa Isabel, Tolima

75 p. Recurso Electr?nicoLas ra?ces finas (di?metro < 2 mm) se han caracterizado por ser un componente radicular importante dentro de la absorci?n de nutrientes y din?mica del carbono. Se evalu? la captura de carbono en ra?ces finas mediante un dise?o completamente al azar con tres tratamientos (bosques, cultivos y pasturas); del mismo modo se utiliz? un dise?o con arreglo en franjas (profundidad: 0-10, 10-20, 20-30, 30-40, 40-50 cm) y cinco repeticiones. Se colectaron bloques de 10 x 10 x 10 cm que fueron lavados y tamizados para separar las ra?ces finas y secadas hasta peso constante. La biomasa de ra?ces estructurales se estim? con la ecuaci?n desarrollada por Cairns et al. (1997). Se encontraron diferencias estad?sticas (p<0,05) en la acumulaci?n de carbono entre sistemas: mayor en bosques que en pasturas y cultivos (ra?ces finas: 4,2 ? 0,6 vs 2,1 ? 0,4 vs 0,6 ? 0,25 t/ha, y estructurales: 26 ? 2,8 vs 10 ? 0,9 t/ha, respectivamente). La profundidad tiene un efecto significativo (p<0,05) en la acumulaci?n de carbono en ra?ces finas, siendo mayor en las primeras capas y reduci?ndose en las profundas: 55% del carbono se encuentra en los primeros 20 cm del suelo y 12% entre 40-50 cm. Los agentes fisicoqu?micos que caracterizan la cobertura del suelo determinan el crecimiento y desarrollo de las ra?ces. La conservaci?n de bosques nativos implica la retenci?n de cantidades importantes de carbono que al reportar un cambio de uso del suelo podr?a generar un incremento en las concentraciones de CO2 a la atm?sfera. Palabras claves: Almacenamiento de carbono, Biodiversidad, Biomasa, Servicios ambientales.Fine roots (diameter < 2 mm) has been characterized as a mean root component in nutrient absorption and carbon dynamics. Carbon sequestration was evaluated inside fine roots through a completely random design with three treatments such as forests; crops and pastures. Similarly, It was applied a design with pursuant slots (depth: 0-10; 10-20; 20-30; 30-40; 40-50 cm) and five repetitions. Blocks were collected of 10 x 10 x 10 cm in dimension which were washed and sifted in order to separate the fine roots and dried them until constant weight. Structural root?s Biomass was estimated with the equation developed by Cairns et al. (1997). It was found statistic differences (p<0,05) on the accumulation of carbon between systems: higher in forests than pastures and crops (fine roots : 4,2 ? 0,6 vs 2,1 ? 0,4 vs 0,6 ? 0,25 t/ha and structural ones: 26 ? 2,8 vs 10 ? 0,9 t/ha, respectively). Depth has a significant effect (p<0,05) on the increasing of carbon at fine roots being higher on the first layers and decreasing at the last ones: 55% of carbon is found in the first 20 cm of the soil and 12% between 40-50 cm. Physicochemical agents that characterize the soil coverage determine the growth and development of roots. Consequently, native forests preservation implies retention of important amounts of carbon since it shows a change on the use of soil could produce an increase on the concentrations of CO2 at the atmosphere. Keywords: Carbon storage, Biodiversity, Biomass, Environmental service

Captura de carbono en ra?ces finas y estructurales en bosques alto-andinos y sistemas agroforestales en asocio con ?rboles dispersos y cultivos en Santa Isabel, Tolima

75 p. Recurso Electr?nicoLas ra?ces finas (di?metro < 2 mm) se han caracterizado por ser un componente radicular importante dentro de la absorci?n de nutrientes y din?mica del carbono. Se evalu? la captura de carbono en ra?ces finas mediante un dise?o completamente al azar con tres tratamientos (bosques, cultivos y pasturas); del mismo modo se utiliz? un dise?o con arreglo en franjas (profundidad: 0-10, 10-20, 20-30, 30-40, 40-50 cm) y cinco repeticiones. Se colectaron bloques de 10 x 10 x 10 cm que fueron lavados y tamizados para separar las ra?ces finas y secadas hasta peso constante. La biomasa de ra?ces estructurales se estim? con la ecuaci?n desarrollada por Cairns et al. (1997). Se encontraron diferencias estad?sticas (p<0,05) en la acumulaci?n de carbono entre sistemas: mayor en bosques que en pasturas y cultivos (ra?ces finas: 4,2 ? 0,6 vs 2,1 ? 0,4 vs 0,6 ? 0,25 t/ha, y estructurales: 26 ? 2,8 vs 10 ? 0,9 t/ha, respectivamente). La profundidad tiene un efecto significativo (p<0,05) en la acumulaci?n de carbono en ra?ces finas, siendo mayor en las primeras capas y reduci?ndose en las profundas: 55% del carbono se encuentra en los primeros 20 cm del suelo y 12% entre 40-50 cm. Los agentes fisicoqu?micos que caracterizan la cobertura del suelo determinan el crecimiento y desarrollo de las ra?ces. La conservaci?n de bosques nativos implica la retenci?n de cantidades importantes de carbono que al reportar un cambio de uso del suelo podr?a generar un incremento en las concentraciones de CO2 a la atm?sfera. Palabras claves: Almacenamiento de carbono, Biodiversidad, Biomasa, Servicios ambientalesFine roots (diameter < 2 mm) has been characterized as a mean root component in nutrient absorption and carbon dynamics. Carbon sequestration was evaluated inside fine roots through a completely random design with three treatments such as forests; crops and pastures. Similarly, It was applied a design with pursuant slots (depth: 0-10; 10-20; 20-30; 30-40; 40-50 cm) and five repetitions. Blocks were collected of 10 x 10 x 10 cm in dimension which were washed and sifted in order to separate the fine roots and dried them until constant weight. Structural root?s Biomass was estimated with the equation developed by Cairns et al. (1997). It was found statistic differences (p<0,05) on the accumulation of carbon between systems: higher in forests than pastures and crops (fine roots : 4,2 ? 0,6 vs 2,1 ? 0,4 vs 0,6 ? 0,25 t/ha and structural ones: 26 ? 2,8 vs 10 ? 0,9 t/ha, respectively). Depth has a significant effect (p<0,05) on the increasing of carbon at fine roots being higher on the first layers and decreasing at the last ones: 55% of carbon is found in the first 20 cm of the soil and 12% between 40-50 cm. Physicochemical agents that characterize the soil coverage determine the growth and development of roots. Consequently, native forests preservation implies retention of important amounts of carbon since it shows a change on the use of soil could produce an increase on the concentrations of CO2 at the atmosphere. Keywords: Carbon storage, Biodiversity, Biomass, Environmental service

Evaluaci?n de la huella h?drica de los sistemas de producci?n agr?cola y pecuario predominantes en la microcuenca la plata, (Ibagu?, Tolima)

116 p. Recurso Electr?nicoLa microcuenca La Plata tributa sus aguas a la cuenca del r?o Combeima, quien abastece agua para el acueducto de Ibagu? (Tolima). La microcuenca cuenta con un ?rea de 2.498 ha, el 86,66% de su cobertura es bosque natural, 7,5% cultivos, 5,75% pastos y 0,15% zonas improductivas. Las actividades productivas han provocado deforestaci?n, aumento en la erosi?n y han alterado la calidad y disponibilidad del agua. A pesar de estas condiciones, no se han definido indicadores de sostenibilidad para el manejo del recurso h?drico en la zona. Por tanto, este trabajo evalua la Huella H?drica (HH) de los sistemas de producci?n agr?cola predominantes en la microcuenca durante el a?o 2015, con el fin de establecer las relaciones causa-efecto a nivel socio-ambiental e indicadores para el manejo sostenible del recurso h?drico. Se calcularon las HH Azul (HA), Verde (HV) y Gris (HG) de los sistemas de producci?n. Los resultados indicaron que la HH de los sistemas de producci?n agr?cola es de 6.628,64 m3.t-1. El Caf? (Coffea arabica Linneo) es el que genera mayor HV. El sistema de producci?n que mayor HG produce es el de Mora (Rubus glaucus Benth). Adem?s, el an?lisis de sostenibilidad evidenci? que la microcuenca presenta un estado cr?tico o ?hotspot? ambiental por competencia de agua verde. Los resultados e indicadores permitieron crear estrategias de respuesta para mejorar la oferta, demanda y calidad del recurso h?drico, con el ?nimo de contribuir a su uso eficiente. Este trabajo recibi? apoyo econ?mico del proyecto ?EOCYT? de la Universidad del Tolima. Palabras claves: Huella H?drica Azul, Huella H?drica Verde, Huella H?drica Gris.The Plata micro-watershed tributes its waters to the Combeima river basin, which supplies water to the Ibagu? aqueduct (Tolima). The microbasin has an area of 2,498 ha, 86.66% of its coverage is natural forest, 7.5% crops, 5.75% pastures and 0.15% unproductive areas. Productive activities have caused deforestation, increased erosion and have altered the quality and availability of water. Despite these conditions, no sustainability indicators have been defined for the management of water resources in the area. Therefore, this work evaluates the Water Footprint (HH) of the predominant agricultural production systems in the microbasin during 2015, in order to establish cause-effect relationships at the socio-environmental level and indicators for the sustainable management of the resource. water HH Blue (HA), Green (HV) and Gray (HG) of the production systems were calculated. The results indicated that the HH of the agricultural production systems is 6,628.64 m3.t-1. Coffee (Coffea arabica Linneo) is the one that generates the highest HV. The production system that produces the most HG is Mora (Rubus glaucus Benth). In addition, the sustainability analysis showed that the microbasin presents a critical state or environmental "hotspot" due to green water competition. The results and indicators allowed to create response strategies to improve the supply, demand and quality of the water resource, with the aim of contributing to its efficient use. This work received financial support from the "EOCYT" project of the Universidad del Tolima.. Keywords: Blue Water Footprint, Green Water Footprint, Gray Water Footprin

Exosomes in head and neck cancer. Updating and revisiting

Exosomes have gone from being considered simple containers of intracellular waste substances to be considered important carriers of cellular signals. Its broad capacity to promote tumour growth, both in situ and metastatic, has greatly intensified scientific research on them. In the same way and depending on its content, its tumour suppressive properties have opened a window of light and hope in the fight against cancer. In the present review we try to gather in a simple and understandable way the most relevant knowledge to date on the role of exosomes in oral squamous cell carcinoma, helping to understand their process of formation, release and activity on the tumour microenvironment

Systemic Effects Induced by Hyperoxia in a Preclinical Model of Intra-abdominal Sepsis

Supplemental oxygen is a supportive treatment in patients with sepsis to balance tissue oxygen delivery and demand in the tissues. However, hyperoxia may induce some pathological effects. We sought to assess organ damage associated with hyperoxia and its correlation with the production of reactive oxygen species (ROS) in a preclinical model of intra-abdominal sepsis. For this purpose, sepsis was induced in male, Sprague-Dawley rats by cecal ligation and puncture (CLP). We randomly assigned experimental animals to three groups: control (healthy animals), septic (CLP), and sham-septic (surgical intervention without CLP). At 18 h after CLP, septic (n = 39), sham-septic (n = 16), and healthy (n = 24) animals were placed within a sealed Plexiglas cage and randomly distributed into four groups for continuous treatment with 21%, 40%, 60%, or 100% oxygen for 24 h. At the end of the experimental period, we evaluated serum levels of cytokines, organ damage biomarkers, histological examination of brain and lung tissue, and ROS production in each surviving animal. We found that high oxygen concentrations increased IL-6 and biomarkers of organ damage levels in septic animals, although no relevant histopathological lung or brain damage was observed. Healthy rats had an increase in IL-6 and aspartate aminotransferase at high oxygen concentration. IL-6 levels, but not ROS levels, are correlated with markers of organ damage. In our study, the use of high oxygen concentrations in a clinically relevant model of intra-abdominal sepsis was associated with enhanced inflammation and organ damage. These findings were unrelated to ROS release into circulation. Hyperoxia could exacerbate sepsis-induced inflammation, and it could be by itself detrimental. Our study highlights the need of developing safer thresholds for oxygen therapy

Employment Expectations and Gross Flows by Type of Work Contract

There is growing interest in understanding firms’ temporary and permanent employment practices and how institutional changes shape them. Using data on Spanish establishments, we examine: (a) how employers adjust temporary and permanent job and worker flows to prior employment expectations, and (b) how the 1994 and 1997 labour reforms promoting permanent employment affected establishments’ employment practices. Generally, establishments’ prior employment expectations are realized through changes in all job and worker flows. However, establishments uniquely rely on temporary hires as a buffer to confront diminishing long-run employment expectations. None of the reforms significantly affected establishments’ net temporary or permanent employment flows.http://deepblue.lib.umich.edu/bitstream/2027.42/40032/3/wp646.pd

Laboratorio m?vil al alcance en el ?rea de ciencias naturales y educaci?n ambiental con los estudiantes del ciclo II del colegio andino San Nicolas

90 p. Recurso Electr?nicoEl proyecto laboratorio m?vil al alcance promueve el aprendizaje significativo de las clases de ciencias naturales, su principal objetivo es brindar al educando herramientas que le permitan tener un ?ptimo aprendizaje. Para definir su estructura y objetivos se realizaron observaciones en el colegio Andino San Nicol?s, ubicado al suroccidente del municipio de Soacha (Cundinamarca), comuna 1. Durante la ejecuci?n de clases de ciencias naturales se evidencio la realizaci?n de clases tradicionales, identificando la necesidad de implementar una herramienta l?dica, un laboratorio que pueda ser trasladado. Para dar respuesta a la pregunta problema, se estableci? que el tipo de investigaci?n en la cual se basara el proyecto es el I.A.P (investigaci?n por acci?n participativa) que permite la interacci?n de dos procesos, el de conocer y el de actuar. Se dise?ara un manual de laboratorio para la utilizaci?n adecuada de los recursos, en este caso m?vil, se dise?a e implementa con una cartilla que explica cada experimento propuesto, interactuando con tres personajes llamados: Paola, Andrea y Luis, autores del proyecto. En los estudiantes el Laboratorio gener? sorpresa y curiosidad su dise?o m?vil les hizo preguntarse: ?Qu? era la caja en forma de casa?, ?Por qu? un laboratorio m?vil?, ?Qu? hay dentro de la caja en forma de casa?; les asombro el uso de materiales comunes que suelen desecharse , con estos se realiza una clase l?dica, la cartilla y sus personajes despertaron su esp?ritu cient?fico, permitiendo el cumplimiento del objetivo del proyecto. Palabras clave: laboratorio m?vil, aprendizaje significativo, I.A.P, din?mica, l?dica.The mobile accessible laboratory project promotes meaningful learning of natural science classes, its main objective is to provide the learner with tools that allow him to have an optimal learning. In order to define its structure and objectives, observations were made at Andino San Nicolas College, located at the southwest of the municipality of Soacha (Cundinamarca), commune 1. During the execution of natural science classes, the realization of traditional classes was evidenced, identifying the need to implement a playful tool, a laboratory that can be transferred. In order to answer the problem question, it was established that the type of research on which the project was based is the I.A.P (participatory action research) that allows the interaction of two processes, that of knowing and acting. A laboratory manual will be designed for the proper use of resources, in this mobile case, it is designed and implemented with a primer explaining each experiment proposed, interacting with three characters called: Paola, Andrea and Luis, authors of the project. In the students the Laboratory generated surprise and curiosity, their mobile design made them wonder: What was the box in the form of a house?, Why a mobile laboratory?, What is inside the box in the form of a house?; I am amazed at the use of common materials that are often discarded, with these a playful class is done, the primer and its characters awakened their scientific spirit, allowing the fulfillment of the project objective. Keywords: mobile laboratory, meaningful learning, I.A.P, dynamic, play