Aspects of rain forest nutrient dynamics at Los Tuxtlas, Mexico.

Several aspects of nutrient cycling were studied in the Lowland Tropical Rain Forest at Los Tuxtlas. This is at (18° 34' - 18° 36’ N, 95° 04' - 95° 09' W) and represents the northernmost extension of the rain forest Formation in the New World. The relationships among the forest structure, small litterfall production (22 months), small litterfall element concentrations, and soil nutrients were investigated. The degree of nutrient resorption between fresh and dehisced leaves was evaluated for several tree species. The forest had a preponderance of mesophylls, a relatively low tree species diversity, basal area, and small litterfall production. An estimation of leaf litterfall contribution was provided for 119 woody species and the temporal variation of the leaf litterfall was described. Soil nutrient concentrations were high probably owing to the volcanic eruption of 1793. Nutrient-element concentrations were relatively high in the small litterfall and fresh leaves, and nutrient resorption was relatively low. The soil nutrient concentrations in pastures of 12, 32, and 52 years of age were compared with the forest and were relatively high in spite of their maintaining a high density of cattle. The soil under isolated trees in the pastures had higher nutrient concentrations than the open pastures. There was a higher diversity of seedling species under the isolated trees but a growth experiment in a tree nursery did not show differences among the soils from the undisturbed forest, open-pastures and under the isolated trees. It seems that soil nutrients are always high at Los Tuxtlas and override any effect of nutrient addition by the isolated trees

3D high definition video coding on a GPU-based heterogeneous system

H.264/MVC is a standard for supporting the sensation of 3D, based on coding from 2 (stereo) to N views. H.264/MVC adopts many coding options inherited from single view H.264/AVC, and thus its complexity is even higher, mainly because the number of processing views is higher. In this manuscript, we aim at an efficient parallelization of the most computationally intensive video encoding module for stereo sequences. In particular, inter prediction and its collaborative execution on a heterogeneous platform. The proposal is based on an efficient dynamic load balancing algorithm and on breaking encoding dependencies. Experimental results demonstrate the proposed algorithm's ability to reduce the encoding time for different stereo high definition sequences. Speed-up values of up to 90× were obtained when compared with the reference encoder on the same platform. Moreover, the proposed algorithm also provides a more energy-efficient approach and hence requires less energy than the sequential reference algorith

Confined photon modes with triangular symmetry in hexagonal microcavities in 2D photonic Crystals

We present theoretical and experimental studies of the size and thickness dependencies of the optical emission spectra from microcavities with hexagonal shape in films of two-dimensional photonic crystal. A semiclassical plane-wave model, which takes into account the electrodynamic properties of quasi-2D planar photonic microcavity, is developed to predict the eigenfrequencies of the confined photon modes as a function of both the hexagon-cavity size and the film thickness. Modes with two different symmetries, triangular and hexagonal, are critically analyzed. It is shown that the model of confined photon modes with triangular symmetry gives a better agreement between the predicted eigenmodes and the observed resonances.Comment: 14 pages, 6 figure

Transporte y movilidad en el marco de la sustentabilidad y competitividad de la ciudad posmoderna

La dinámica urbana depende de tres tipos de factores: físicos, funcionales y morales. Cada uno de ellos representa una dimensión de análisis de la ciudad. El transporte urbano en es un componente de la dimensión funcional, el comportamiento de los individuos se relaciona con la dimensión moral y las características locacionales de los usos del suelo y la infraestructura se asocian con la dimensión física. El propósito del presente trabajo es exponer las características y el papel del transporte urbano de pasajeros en la movilidad de la ciudad posmoderna en el marco de los discursos sobre la sustentabilidad y la competitividad urbanas bajo el análisis de los factores físicos, funcionales y morales mencionados anteriormente.La dinámica urbana depende de tres tipos de factores: físicos, funcionales y morales. Cada uno de ellos representa una dimensión de análisis de la ciudad. El transporte urbano en es un componente de la dimensión funcional, el comportamiento de los individuos se relaciona con la dimensión moral y las características locacionales de los usos del suelo y la infraestructura se asocian con la dimensión física. El propósito del presente trabajo es exponer las características y el papel del transporte urbano de pasajeros en la movilidad de la ciudad posmoderna en el marco de los discursos sobre la sustentabilidad y la competitividad urbanas bajo el análisis de los factores físicos, funcionales y morales mencionados anteriormente

Framework for Development Triages through Mobile Applications

The emergency triage is being implemented due to the congestion of the emergency services, for several reasons, such as: easy access to the patient, demanding an immediate diagnostic an medical aid, prioritizing severely ill patients rather than patients with minor problems that make improper use of the emergency areas. The objective is building a system, integrated to the main system of health organization, for management of emergency triage. To do this, we have analysed and developed a system which allows us to evaluate patients through a mobile application. Results suggest that the integration of emergency triage to mobile application, helps to improve and optimize resource management and decrease the response time. In conclusion, this system optimizes the resources implemented as well as an increase of customer satisfaction

Microcystin-LR equivalents and their correlation with Anabaena spp. in the main reservoir of a hydraulic system of Central Mexico

The occurrence of cyanobacterial blooms is a characteristic of eutrophic inland water bodies. Valle de Bravo reservoir (Mexico State, Mexico) is the main source of water for the Cutzamala Hydraulic System, which supplies drinking water to the west of Mexico City (~6 million consumers) and suburban areas of Mexico State. The goal of this study was to determine the presence of microcystins (MC-LR equivalents) and their relationship with toxic populations of cyanobacteria recorded some years ago in this important reservoir. We measured the concentration of MC-LR equivalents using a commercial kit (EnviroLogix) based on the ELISA test. The calculation of abundance and biovolume was carried out monthly from February to November 2010. The presence of MC-LR equivalents was related to the biovolume of Anabaena planctonica. The values of this toxin from February to June exceeded the World Health Organization (WHO) provisional guideline (1 µg L-1) for finished drinking water sources, particularly in April when the highest value was recorded (5.56 μg L-1). In addition, in April, May, June, and August, the abundance of cyanobacteria exceeded the WHO moderate risk level (10 × 104 cells mL-1) for recreational activities. This study furthers investigations ranging from the characteristics of the water column to benthic cyanobacteria and molecular biology tests to establish which species are toxic in the reservoir

SmartSantander: IoT experimentation over a smart city testbed

This paper describes the deployment and experimentation architecture of the Internet of Things experimentation facility being deployed at Santander city. The facility is implemented within the SmartSantander project, one of the projects of the Future Internet Research and Experimentation initiative of the European Commission and represents a unique in the world city-scale experimental research facility. Additionally, this facility supports typical applications and services of a smart city. Tangible results are expected to influence the definition and specification of Future Internet architecture design from viewpoints of Internet of Things and Internet of Services. The facility comprises a large number of Internet of Things devices deployed in several urban scenarios which will be federated into a single testbed. In this paper the deployment being carried out at the main location, namely Santander city, is described. Besides presenting the current deployment, in this article the main insights in terms of the architectural design of a large-scale IoT testbed are presented as well. Furthermore, solutions adopted for implementation of the different components addressing the required testbed functionalities are also sketched out. The IoT experimentation facility described in this paper is conceived to provide a suitable platform for large scale experimentation and evaluation of IoT concepts under real-life conditions.This work is funded by research project SmartSantander, under FP7-ICT-2009-5 of the 7th Framework Programme of the European Community. Authors would like to acknowledge the collaboration with the rest of partners within the consortium leading to the results presented in this paper

Evaluación de metodologías didácticas en trabajos de fin de grado en titulaciones de Ciencias Experimentales

Mediante encuestas a estudiantes que se encuentran finalizando el Trabajo de Fin de Grado (TFG) y profesores que dirigen de los seis grados de la facultad de Ciencias (Biología, Ciencias del Mar, Geología, Matemáticas, Óptica y Optometría, Química) de la Universidad de Alicante, se han identificado los puntos de menor fortaleza de los TFGs independientemente para cada grado. A continuación, hemos comparado los resultados entre grados para ver el nivel de similitud entre ellos y la singularidad de cada uno de ellos. A partir de ahí, hemos identificado los posibles factores que configuran cada TFG con el fin de intentar entender su singularidad en cada caso. Esta información es importante para ayudarnos a comprender cómo se podrían fortalecer posibles carencias en TFGs específicos. Con esta información y en base a la experiencia previa, proponemos medidas que permitan favorecer la implementación y desarrollo de los TFGs. Con estas propuestas se espera mejorar la eficiencia de los TFGs y conseguir un mayor nivel de satisfacción y el rendimiento en esta asignatura común en todos los grados

Análisis de los Trabajos de Fin de Grado desde la visión docente

El Trabajo Fin de Grado (TFG) en los grados de la Facultad de Ciencias, constituye una asignatura con importantes competencias transversales que representa la fase final del plan de estudios, y supone la realización por parte del estudiante de un proyecto, memoria o estudio bajo la supervisión de un tutor o tutora. En este trabajo se realiza un estudio general de los TFGs y la utilización del UA-project, desde la visión del profesorado. Para poder optimizar el desarrollo de los TFGs, en este trabajo se realizó un análisis interno mediante un cuestionario. Para dar mayor amplitud y proyección a la propuesta se han enviado los cuestionarios a profesores de todos los grados de la Facultad de Ciencias: Biología, Ciencias del Mar, Química, Geología, Matemáticas y Óptica y Optometría. Estos cuestionarios reflejan la experiencia docente obtenida en los últimos años en la tutorización de los TFGs, para así poder obtener conclusiones e ideas de mejora para su posterior aplicación