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Tropical dry forests (TDF) in Mesoamerica are highly endangered by the expansion of human activities (e.g., agriculture and cattle ranching). In contrast, TDF in Costa Rica have experienced outstanding restoration due to changes in economic and conservation policies. Currently TDF landscapes in Costa Rica are a mosaic of different successional stages. Tree breeding systems and pollination and dispersal syndromes are key elements for understanding restoration processes in TDFs. In this study we describe and compare tree species composition and diversity in three TDF successional stages (early, intermediate and late) in Guanacaste, Costa Rica. We describe for the first time tree species breeding systems and pollination and dispersal syndromes for the largest and most significant TDF remnant in Mesoamerica. We set up nine plots, three per successional stage, and we measured and identified 1,072 trees from 96 species. Species richness and diversity indices were higher for the intermediate stage. Monoecy was the most common breeding system, as in other tropical life zones. Insects were the dominant pollinators, facilitated by the trees’ small inflorescences. Wind was found to be not only the next most influential pollinator, mainly in open and disturbed early forests, but also it was also a good seed dispersal agent. As TDF age increases so does the relevancy of birds and mammals as dispersers; the late stage therefore has more tree species with adaptations to these dispersers. © Branko Hilje, Julio Calvo-Alvarado, César Jiménez-Rodríguez and Arturo Sánchez-Azofeifa.

The proteolytic system of the phytopathogenic and dimorphic fungus Ustilago maydis is not known. In this work, we report the presence of at least four proteases from two haploid strains of U. maydis. Activities of two proteinases pumA and pumB, aminopeptidase pumAPE, and dipeptidylaminopeptidase pumDAP were measured under several nutritional and morphological conditions, including the yeast-mycelium transition. The activity of pumA was found in the intracellular and extracellular fractions, pumAi and pumAe, respectively. The latter activity was detected only during the yeast-mycelium dimorphic transition induced by growth at acid pH in a medium containing ammonium as the sole nitrogen source. Activity of pumAe was partially inhibited by Pepstatin A, which also inhibited mycelium formation. Activity of pumAi was inhibited by this specific inhibitor of aspartyl-proteases. Activity of pumB was detected in intracellular and extracellular fractions, mostly bound to an endogenous inhibitor, which was removed by treatment at acid pH. This fungus contains at least two soluble pumAPE, which might be metallo-proteases, because they were inhibited by EDTA and 1-10, phenanthroline. When the fungus was grown in media containing proline or corn infusion as the nitrogen source, an intracellular pumDAP activity was detected. No carboxypeptidase activity was found with N-benzoyl-l-tyrosine-4-nitroanilide as substrate in any of the conditions tested in any of the U. maydis strains analyzed.

Oncologia mèdica; Mentor resident; Càrrega de treball Oncología médica; Mentor residente; Carga de trabajo Medical oncology; Resident mentor; Workload Purpose: The Spanish Society for Medical Oncology (SEOM, for its acronym in Spanish) and the National Commission for the Specialty of Medical Oncology seek to highlight the important workload and unrecognized dedication entailed in working as a Medical Oncology (MO) resident mentor, as well as its relevance for the quality of teaching units and the future of the specialty. Materials and methods: The current situation and opinion regarding the activity of MO resident mentors was analyzed by reviewing the standing national and autonomic community regulations and via an online survey targeting mentors, residents, and physicians who are not MO mentors. The project was supervised by a specially designated group that agreed on a proposal containing recommendations for improvement. Results: Of the MO mentors, 90% stated that they did not have enough time to perform their mentoring duties. An estimated 172 h/year on average was dedicated to mentoring, which represents 10.1% of the total time. MO mentors dedicate an average of 6.9 h/month to these duties outside their workday. Forty-five percent of the mentors feel that their role is scantly recognized, if at all. Conclusions: The study reveals the substantial dedication and growing complexity of MO resident mentoring. A series of recommendations are issued to improve the conditions in which it is carried out, including the design of systems that adapt to the professional activity in those departments that have time set aside for mentoring tasks. This study was funded as an unrestricted grant by Servier. Servier did not have any intervention in the discussion and outcomes of this report.

A segunda edição da série Instituições para o Povo mostra os bancos públicos de desenvolvimento da América Latina e do Caribe frente a um novo paradigma.Nos seis capítulos que compõem o estudo, o tema dos bancos públicos de desenvolvimento é abordado a partir de uma perspectiva integral, analisando os aspectos institucionais necessários e os instrumentos financeiros e não financeiros disponíveis para poder consolidar o papel desses bancos no fomento do desenvolvimento com responsabilidade financeira e fiscal. O enfoque é estruturado a partir da resposta às novas interrogações propostas pela conjuntura atual, relacionadas com a relevância dessas instituições dentro dos sistemas financeiros, as avaliações de impacto de sua atuação e os novos desafios e oportunidades com que se defrontam.

The second publication in the series "Institutions for People" focuses on the public development banks of Latin America and the Caribbean as they enter a new paradigm. In the last 10 to 15 years, these institutions have made considerable progress in the region towards fulfilling their undoubted potential as effective public policy tools. If this trajectory of operational and financial improvement can be consolidated, and public development banks can demonstrate their impact on development, they will be well placed to face even more complex challenges, such as climate change and productive development. Throughout its six chapters, this book tackles the theme from an integral perspective, analyzing the institutional aspects needed, and the financial and nonfinancial instruments available, to consolidate the role of public development banks in promoting development with fiscal and financial responsibility. The approach is structured according to the questions arising from the current situation, which relate to the significance of these institutions within financial systems, the impact evaluations of their performance, and the new challenges and opportunities they face. In summary, this book is useful for governments and public development banks, as well as for academics and decision makers interested in achieving sustainable financing for both current and future generations in the region.

We derive a necessary and sufficient condition for a quantum process to be Markovian which coincides with the classical one in the relevant limit. Our condition unifies all previously known definitions for quantum Markov processes by accounting for all potentially detectable memory effects. We then derive a family of measures of non-Markovianity with clear operational interpretations, such as the size of the memory required to simulate a process, or the experimental falsifiability of a Markovian hypothesis., 5+3 pages, 4 figures; split off from earlier version of arXiv:1512.00589

La segunda edición de la serie Instituciones para la gente presenta a los bancos públicos de desarrollo de América Latina y el Caribe frente a un nuevo paradigma. En los últimos 10 a 15 años la región ha visto un avance importante de estas instituciones para lograr su gran potencial como instrumentos efectivos para apoyar políticas públicas. Si consolidan la trayectoria de mejora operacional y financiera y demuestran su impacto en el desarrollo, estarán en una excelente posición para enfrentar los desafíos más complejos, como el cambio climático y el desarrollo productivo. A lo largo de los seis capítulos que lo componen, el estudio aborda el tema desde una perspectiva integral, analizando los aspectos institucionales necesarios y los instrumentos financieros y no financieros disponibles para poder consolidar el rol de los bancos públicos de desarrollo en el fomento del desarrollo con responsabilidad financiera y fiscal. El enfoque se estructura a partir de la respuesta a nuevos interrogantes que surgen de la coyuntura actual, relacionados con la relevancia de estas instituciones dentro de los sistemas financieros, las evaluaciones de impacto sobre su actuación y los nuevos retos y las oportunidades que tienen ante sí.

Facultad de Ingeniería Química. Maestría en Ciencias en Ingeniería Química This work presents the results of an investigation that consisted of the deposit of a metal on a substrate and the growth of thin films by means of the electrochemical anodization technique. The experimental analysis of the structural properties of the films is described. A stainless steel substrate coated with metallic titanium (Ti) was used for the synthesis of the nanostructured films. To do this, it was proposed to use the Physical Vapor Deposition (PVD) technique in its cathodic arc variant for the Ti coating because it provides important advantages such as: adequate uniformity in terms of its thickness, microstructure and its adherence on steel plates type 316 stainless steel. This coated plate is the one that was used as the anode in the anodization, that is, on which the formation or growth of TiO2 nanotubes was carried out and a stainless steel plate is used as the cathode, the synthesis was carried out in an electrolytic medium using ammonium fluoride as a control agent. The anodization process tests were carried out at constant temperature, but at different time and voltage parameters, obtaining highly ordered and vertically oriented nanostructures for all samples. In order to determine the effects of the processing parameters on the morphology, an analysis of the structural properties of the samples was carried out using low-angle X-ray diffraction and field emission scanning electron microscopy. En este trabajo se presentan los resultados de una investigación que consistió en el depósito de un metal sobre un substrato y el crecimiento de películas delgadas empleando la técnica de anodización electroquímica. Se describe el análisis experimental de las propiedades estructurales de las películas. Se empleó un substrato de acero inoxidable recubierto de Titanio metálico (Ti) para la síntesis de las películas nano-estructuradas. Para esto se planteó utilizar la técnica de Depositación Física de Vapor (PVD) en su variante de arco catódico para el recubrimiento de Ti debido a que provee importantes ventajas como: adecuada uniformidad en cuanto a su espesor, microestructura y su adherencia sobre placas de acero inoxidable tipo 316. Esta placa recubierta es la que se utilizó como ánodo en la anodización, es decir, sobre la que se llevó a cabo la formación o el crecimiento de nanotubos de TiO2 y como cátodo se emplea una placa de acero inoxidable, la síntesis se llevó a cabo en medio electrolítico usando Fluoruro de Amonio como agente controlador. Las pruebas del proceso de anodizado se llevaron a cabo a temperatura constante, pero a diferentes parámetros de tiempo y voltaje, obteniéndose para todas las muestras nanoestructuras altamente ordenadas y con orientación vertical. Con el fin de determinar los efectos de los parámetros de procesamiento sobre la morfología se llevó a cabo un análisis de las propiedades estructurales de las muestras utilizando difracción de rayos X de bajo ángulo y Microscopia electrónica de barrido de emisión de campo.

Tesis - (Doctorado en Comunicación) 1. #YoSoy132: origen, desarrollo. 2. Sobre el diálogo en la web.2.0 y el debate en 140 caracteres. 3. Transformaciones del espacio público y de la esfera pública. Un breve acercamiento y su evolución histórico. 4. La fijación de la agenda como escenario de interacción en la web 2.0 y el surgimiento de los líderes de opinión en la Red. 5. Los líderes de opinión que le dieron vida al #YoSoy132 en Twitter.

93 p. Tensegrity structures are used in fields like architecture, engineering and biomedicine, and have new rising applications in robotics. The static analysis of these structures might be performed for the initial configuration of the structure in absence of external forces. This analysis leads to a set of equations generated from the Newtonian mechanic or the virtual work principle. Because this initial configuration of the structure is important, if different configurations can be found, it will lead to new applications and uses. There are numerical methods that search all the possible solutions in polynomial systems, one of them is the continuation method, that has been used in different fields such as biology and specially in robotics. In this work, two planar tensegrity structures are chosen to perform an analysis of static equilibrium using the virtual work principle, then a polynomial system is generated and solved with a computational implementation of the continuation method. The objective is to find different sets of solutions that might lead to new configurations of the tensegrity structures.

Aprendizaje es un cambio relativo en el comportamiento, que puede adquirirse a través de las relaciones temporales que los organismos establecen con el medio y que ocurre como resultado directo de la experiencia. Según Thorpe (1963) y Hölldobler & Wilson (1990), el aprendizaje puede estar dado por dos formas o categorías de modificación comportamental: - Habituación, cuando la experiencia disminuye la intensidad de una respuesta. La habituación es el proceso adaptativo en el que, un individuo reconoce menos un estímulo peligroso como tal, alcanzando la calma. - Aprendizaje asociado, cuando los individuos adquieren respuestas condicionadas por la asociación de recompensas (feromonas de atracción, comida, etc.) con estímulos sin un sentido previo., 1. Introducción, 2. Marco Teórico, 3. Objetivos, 4. Planteamiento del problema, 5. Justificación, 6. Estado del arte, 7. Metodología, Pregrado, Licenciado en Biología y Educación Ambiental