Economic Growth and Regional Integration in Mexico

In this paper we examine the regional structure of output growth, volatility and prosperity in Mexico, focusing in particular on the degree of integration between both the regions and the individual states of the country. The results suggest that there is a high degree of similarity across the regions in the responses to domestic and international shocks affecting the economy, but there are also significant differences across the individual states within each region. We identify a positive relationship between output growth and volatility, but the relationship between growth and regional disparities appears to be negative, suggesting that higher (lower) growth is generally associated with lower (higher) regional dispersion in per capita GDP levels

La Geografía a las puertas del tercer milenio a partir de las tesis doctorales leídas en los noventa

Tendencies of research in contemporary Geography were analysed by means of the latest PhD studies in Geography in Spanish Universities. Our analysis shows that research is still focused on local and regional environments with different techniques and methods. There is still need to actualise the descriptors of PhD studies classification.Se han analizado las tendencias de la investigación en la Geografía actual a través de las tesis doctorales de Geografía en los últimos años en las Universidades españolas. El análisis muestra que continua la tendencia a investigar sobre ámbitos locales y regionales con una gran pluralidad de técnicas. Se ha detectado también que existe una necesidad de actualizar los descriptores de clasificación de las tesis doctorales de la base de datos TESEO.Les tendences des ênquetes dans la géographie ont etés analysés a travers les théses doctorales dans les dernieres années dans les Universités Espagnoles. L´analise montre que la téndence continue a ênqueter sur les cadres locaux et regionaux avec une grande pluralité de techniques. Il a eté detecté aussi qu´il existe un besoin de metre a jour les déchifreurs de triage des théses doctorales sur les données TESEO

Thermoelectrics

Metallic Ag microsphere in a ceramic matrix Thermoelectricity is the direct solid-state conversion between thermal and electrical energy, without any moving parts, due to the well-known Seebeck effect. Currently, more than half of the energy produced ends up in the form of wasted heat: thermoelectric harvesting and energy conversion constitutes an solution to improve the energy efficiency of classical industrial and domestic energy transforming processes, through thermoelectric modules

Improving thermoelectric properties of Ca 3 Co 4 O 9+d through both Na doping and K addition at optimal values

Ca 2.93 Na 0.07 Co 4 O y /x wt% K 2 CO 3 (x = 0.00, 0.01, and 0.03) polycrystalline ceramics were prepared by conventional solid-state method. XRD results have shown that all samples predominantly include Ca 3 Co 4 O 9 phase together with small amounts of secondary phases. SEM images show that all samples have randomly oriented plate-like grains in different sizes. The electrical resistivity measurement showed that electrical properties of Ca 3 Co 4 O 9 ceramics can be improved significantly by both, Na doping and K addition at their optimal values. The effect of dopants on thermoelectric properties of Ca 3 Co 4 O 9 was examined by both, Seebeck coefficient and power factor, being higher in K-added than in the pure samples, indicating that thermoelectric properties of samples are positively affected when alkaline elements enter into their structure

Spatial and temporal variability of CO2 emisions in soils under conventional tillage and no-till farming

Agricultural soils can act as a carbon sink depending on the soil management practices employed. As a result of this functional duality, soil management systems are present in international documents relating to climate change mitigation. Agricultural practices are responsible for 14% of total greenhouse gas emissions (GHG’s) (MMA, 2009)(1). Conservation agriculture (CA) is one of the most effective agricultural systems for reducing CO2 emissions, as it increases the sequestration of atmospheric carbon in the soil. In order to assess the performance of CA in terms of CO2 emissions, a field trial was conducted comparing soil derived CO2 fluxes under No-till (NT) farming and under conventional tillage. Three pilot farms were selected in the cereal-growing area of southern Spain, located in Las Cabezas de San Juan (Seville), Carmona (Seville) and Cordoba. Each pilot farm comprises six experimental plots with an approximate area of five hectares; three of the six plots implement CA practices, while the other three use conventional tillage techniques. The subdivision of each tillage system into 3 plots allowed the simultaneous cropping of the three crops of the wheat-sunflower-legume rotation each year. Results showed that carbon dioxide emissions were 31 to 91% higher in tilled soils than in untilled soils, and that there was a great seasonal variability of CO2 emissions, as weather conditions also differed considerably for the different sampling periods. In all cases, the CO2 fluxes emitted into the atmosphere were always higher when soil was subject to conventional tillage

Super star clusters and Supernovae in interacting LIRGs unmasked by NIR adaptive optics

We report on an on-going near-IR adaptive optics survey targeting interacting luminous IR galaxies. High-spatial resolution NIR data are crucial to enable interpretation of kinematic, dynamical and star formation (SF) properties of these very dusty objects. Whole progenitor nuclei in the interactions can be missed if only optical HST imaging is used. Here we specifically present the latest results regarding core-collapse supernovae found within the highly extincted nuclear regions of these galaxies. Direct detection and study of such highly obscured CCSNe is crucial for revising the optically-derived SN rates used for providing an independent measurement of the SF history of the Universe. We also present thus-far the first NIR luminosity functions of super star cluster (SSC) candidates. The LFs can then be used to constrain the formation and evolution of SSCs via constraints based on initial mass functions and cluster disruption models.Comment: 6 pages. To appear in proceedings of 'Galaxies and their Masks' (Namibia, April 2010), published by Springer, New York, eds. D.L. Block, K.C. Freeman, I. Puerar

Analytical Expressions for Radiative Opacities of Low Z Plasmas

In this work we obtain analytical expressions for the radiative opacity of several low Z plasmas (He, Li, Be, and B) in a wide range of temperatures and densities. These formulas are obtained by fitting the proposed expression to mean opacities data calculated by using the code ABAKO/ RAPCAL. This code computes the radiative properties of plasmas, both in LTE and NLTE conditions, under the detailed-level-accounting approach. It has been successfully validated in the range of interest in previous works

Influence of Ca substitution by Mg on the Ca3Co4O9 performances

Ca3-xMgxCo4O9 polycrystalline thermoelectric ceramics with small amounts of Mg have been synthesized by the classical solid state method. Microstructural characterizations have shown that all the Mg has been incorporated into the Ca3Co4O9 structure and no Mg-based secondary phases have been identified. Apparent density measurements have shown that samples do not modify their density until 0.05 Mg content, decreasing for higher contents. Electrical resistivity decreases and Seebeck coefficient slightly raises when Mg content increases until 0.05 Mg addition. The improvement in both parameters leads to higher power factor values than the usually obtained in samples prepared by the conventional solid state routes and close to those obtained in textured materials.Se han preparado cerámicas termoeléctricas policristalinas de Ca3-xMgxCo4O9, con pequeñas cantidades de Mg, utilizando el método clásico de estado sólido. La caracterización microestructural ha mostrado que el Mg se ha incorporado en la estructura del Ca3Co4O9 y que no se han formado fases secundarias con el Mg. Las medidas de densidad aparente han mostrado que las muestras prácticamente poseen la misma densidad hasta un contenido de 0.05 Mg, disminuyendo para contenidos mayores. La resistividad eléctrica disminuye y el coeficiente Seebeck aumenta cuando el contenido de Mg se incrementa hasta valores de 0.05. La mejora de ambos parámetros conduce a valores del factor de potencia mayores que los obtenidos en muestras preparadas por la vía convencional de estado sólido, alcanzando valores próximos a los que se encuentran en materiales texturados

Qué papel juega el hongo Phytophthora cinnamomi en el desarrollo de la regeneración natural y repoblaciones de encina y alcornoque

Se presentan los resultados resumidos de tres trabajos realizados para conocer el papel que juega el hongo Phytophthora cinnamomi en el desarrollo de plántulas de encina (Quercus ilex) y alcornoque (Quercus suber). Se realizaron dos prospecciones para detectar la presencia de P.cinnamomi en focos de seca en dehesas de encina y alcornoque de Extremadura en 1991-1992 y 1999-2000. El porcentaje de focos en los que se detectó la presencia de P. cinnamomi ha permanecido relativamente estable entre las dos prospecciones. También se determinó la tasa de crecimiento relativo para nueve aislados de P. cinnamomi a diferentes temperaturas, observando una elevada variabilidad tanto en la temperatura óptima de crecimiento como en el valor de la propia tasa diaria de crecimiento máxima. También se estudió la emergencia y supervivencia de plántulas de encina y alcornoque procedentes de dos dehesas ecológicamente diferentes, cultivadas en condiciones controladas en suelos de estas dehesas infectados naturalmente con P. cinnamomi y en estos mismos suelos previamente desinfectados en autoclave. Un factor limitante en los procesos de regeneración natural y en las repoblaciones por siembra directa de encinas y alcornoque puede ser su alta susceptibilidad a las infecciones por P. cinnamomi.Por último, se estudió durante dos años consecutivos, la supervivencia de las plantas de encina de una repoblación sobre un suelo naturalmente infectado con P. cinnamomi en la provincia de Badajoz (SO de España). Los resultados obtenidos se discuten teniendo en cuenta el déficit hídrico, los daños por P. cinnamomi, la competencia con otras especies y las posibles medidas sanitarias que amortigüen los daños en las repoblaciones con encinas._______________________________Three different studies were performed with the aim to determine the role of Phytophthora cinnamomi in the early development of seedlings of holm oak (Quercus ilex) and cork oak (Quercus suber). Two surveys, for the presence of Phytophthora cinnamomi in declining holm oak and cork oak stands in Extremadura (SW Spain) were performed in 1991-1992 and 1999-2000. The percentage of decline foci where P. cinnamomi is envolved has remained relatively stable in the lapse of time between the two surveys. Growth rates were determined for 9 P. cinnamomi isolates. Considerable variation in optimum growth temperatures and in daily growth rates occurred among isolates. The emergence and survival of pregerminated holm oak and cork oak acorns from two ecologically different dehesas (Mediterranean open woodlands) were studied in two soils from these stands naturally infected with P. cinnamomi, and in the same soils previously sterilized in the autoclave. The demonstrated high susceptibility of holm and cork oak young seedlings to P. cinnamomi could be a limiting factor in mediterranean opend woodlands (dehesas) not only in natural regenerationprocesses but also when reforestation by direct sowing is implemented. Finally, the viability of 1 year old holm oak seedlings in a soil naturally infected with P. cinnamomi was studied during two consecutive years in a plot located in SW Spain. Results obtained are discussed in the framework of seasonal water deficit, P. cinnamomi damage, weed competition and sanitation thechniques to be used in declined holm oak stands in Spain