Wind loads analysis at the anchorages of the Talavera de la Reina cable stayed bridge

This paper describes wind tunnel tests performed on wind tunnel models of the Talavera de la Reina cable stayed bridge. The work describes the aeroelastic model construction and it is focused on the evaluation and analysis of the mean and peak wind loads at the tower foundation and the cable anchorages since these data can be very useful by the bridge manufacturer as a support for the bridge design. The work is part of a complete wind tunnel study carried out to analyze the aeroelastic stability of the bridge

Is drought altering plant populations in the mountainous region of Northeastern Mexico?

Mortality in six plant species was examined in the vegetation of a mountain region in Northeastern Mexico and hypotheses of survival pathways within populations in the ecosystem were tested. Significant differences in the general mortality pattern were found among species indicating species-specific responses to stress gradients. Average mortality differed among species: Yucca carnerosana, 33.8%; Pinus cembroides, 29.9%; Larrea tridentata, 25.9%; Hechtia podantha, 13.7%; Agave lechuguilla, 13.0%; and Thelocactus santaclarensis, 9.0%. Within populations, mortality increased with water stress and survivorship increased with less stressful environments. Results from this study may be useful for the development of a management plan to support the conservation and sustainable use of forest vegetation in this mountain community

Tuberculosis: A Risk Factor Approach

One in three people in the world is infected with Mycobacterium tuberculosis, and 10% of infected individuals will develop the disease at any time in their lifetime. Today, despite the advances in diagnosis and treatment, tuberculosis (TB) remains as one of the biggest challenges in global public health, and low and middle-income countries are the most affected. The risk for developing the disease depends on endogenous, exogenous, and environmental factors. Among the most relevant conditions that could precipitate TB development are those that affect the host-immune response. HIV infection increase about 20 times the risk of TB, and other more common conditions, such as diabetes mellitus, malnutrition, and smoking, also contribute in a big way to the TB pandemic. Global TB control programs in order to achieve the disease control objectives must integrate strategies that have a direct impact on risk factors, not only at an individual level but also on a public health policy level. Here, we review some of the most important risk factors for the development of TB, as one of the most relevant ways for TB control

Contribución al conocimiento del abejaruco común Merops apiaster en la provincia de Sevilla

Se describen en este estudio dos colonias de nidificación del abejaruco común Merops apiaster, situadas en diferentes zonas de la provincia de Sevilla. Para el estudio se hace una descripción de las zonas donde se localizan las dos colonias estudiadas y tarnbién se han definido una serie de variables respecto a la disposición y estructura de la galeria de nidificación: disposición del nido sobre el terreno, ejes horizontal y vertical de la galeria de nidificación, distancia horizontal y vertical entre galerias adyacentes, y longitud de la galeria de nidificación. Los resultados obtenidos muestran que la colonia 1 presenta una gran variabilidad en la distribución de las galerías de nidificación con una alta densidad de individuos. En el caso de la colonia 2, presenta homogeneidad en la distribución de las galeria de nidificación, con una baja densidad de población.In the present work, two colonies of bee eaters Merops apiaster, located in different zones of the province of Seviile, both on cliffs, have been described. A primary description of two areas of study is made and two sets of variables have been defined, one in regard to nest relative position -vertical and horizontal distance between adjacent galleries, and in relation to ground levels- and the other related to the structure of the nesting gailery -horizontal and vertical axes, and length. Results showed the colony by river Guadiamar presents high values both variability in the distribution of nesting holes and population density. The colony by river Guadalquivir presents homogeneity in the distribution of nesting holes and low population density

IODP Expedition 338: NanTroSEIZE stage 3: NanTroSEIZE plate boundary deep riser 2

The Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) is designed to investigate fault mechanics and seismogenesis along a subduction megathrust, with objectives that include characterizing fault slip, strain accumulation, fault and wall rock composition, fault architecture, and state variables throughout an active plate boundary system. Integrated Ocean Drilling Program (IODP) Expedition 338 was planned to extend and case riser Hole C0002F from 856 to 3600 meters below the seafloor (m b.s.f.). Riser operations extended the hole to 2005.5mb.s.f., collecting logging-while-drilling (LWD) and measurement-while-drilling, mud gas, and cuttings data. Results reveal two lithologic units within the inner wedge of the accretionary prism that are separated by a prominent fault zone at ¿ 1640mb.s.f. Due to damage to the riser during unfavorable winds and strong currents, riser operations were suspended, and Hole C0002F left for re-entry during future riser drilling operations. Contingency riserless operations included coring at the forearc basin site (C0002) and at two slope basin sites (C0021 and C0022), and LWD at one input site (C0012) and at three slope basin sites (C0018, C0021 and C0022). Cores and logs from these sites comprehensively characterize the alteration stage of the oceanic basement input to the subduction zone, the early stage of Kumano Basin evolution, gas hydrates in the forearc basin, and recent activity of the shallow megasplay fault zone system and associated submarine landslides. © Author(s) 2014.Peer Reviewe

Application of computational methods in the assessment of the aeroelastic response of cable supported bridges

En este trabajo se muestra el potencial de los métodos computacionales para analizar la respuesta frente a la acción del viento de los puentes soportados por cables, y se evalúa su capacidad para sustituir a las campañas experimentales en túnel de viento, particularmente en las fases iniciales del diseño. Se ha tomado como caso de estudio el diseño preliminar propuesto para el proyecto real de un puente atirantado continuo con 2 vanos de 650 m y sección transversal en cajón. Así, se han evaluado numéricamente los coeficientes aerodinámicos de la sección transversal y se ha simulado la respuesta no estacionaria frente al desprendimiento de torbellinos utilizando software comercial de mecánica de fluidos computacional. Además, se ha analizado, mediante un código propio, la respuesta de la estructura frente a los fenómenos del flameo y el bataneo utilizando la metodología híbrida y adoptando valores de las funciones experimentales de flameo pertenecientes a una sección transversal de geometría similar. Los resultados computacionales obtenidos se han validado comparándolos con datos experimentales de puentes semejantes publicados por otros autores. Se ha comprobado que el conjunto de métodos adoptados ofrece resultados fiables con costes moderados, por lo que el planteamiento descrito es muy atractivo en la fase inicial del proyecto de puentes de gran vano o en trabajos de diseño conceptual.The possibilities of computational methods for assessing the response of cable supported bridges under wind action are considered in this work. The main objective is to study the possibilities of substituting wind tunnel campaigns by computer based analyses, particularly at the early design stage. The preliminary proposed design for a continuous cable-stayed bridge with two main spans of 650 m and a single box girder deck has been considered as a case study. The force coefficients of the deck cross-section have been computed and the unsteady response associated to vortex-shedding has been simulated using CFD commercial software. Furthermore, an in-house piece of software has been employed to obtain the response for flutter and buffeting phenomena adopting the hybrid approach; with that purpose the experimental flutter functions of a similar box girder deck were adopted. The computational results have been validated by comparison with similar experimental results published by other researchers. It has been verified that the set of adopted methods offers reliable results with moderate costs; therefore, the proposed approach is very suitable at the early design stage of long span bridges or at conceptual design works.Peer Reviewe

Data analysis and tools applied to modeling and simulation of a PV system in Ecuador

This paper presents a research was carried out for the management of a photovoltaic system in a Microgrid, with applications and the use of tools applied to modeling and computational simulation in the Microgrid laboratory implanted in the facilities of the University of Cuenca (Ecuador). Additionally, through the use of automatic learning techniques, the behavior of the photovoltaic system has been modeled in the study area based on radiation and temperature with very good results. In addition, several applications can be made in real engineering studies such as feasibility, performance analysis, energy estimation, educational models, etc