Interpretando la Mina Rica (Pulpí, Almeria): estructura, mineralogía y geoquímica.

En este trabajo se presenta la estructura, mineralogía y geoquímica de la Mina Rica, un excelente ejemplo de la metalogenia del SE peninsular. Para ello se ha realizado la cartografía geológica detallada de las galerías, el estudio etrográfico de las zonas mineralizadas y no mineralizadas y el análisis isotópico de los sulfatos y sufuros

La competencia mediática como reto para la educomunicación: instrumentos de evaluación

Technological advances make new resources available to educational agents in order to enhance learning, but their use requires developing basic competencies or skills in students and is a challenge to the entire educational community. In this context, media competence becomes fundamental for encouraging responsible, efficient and democratic use of media resources by citizens. Here we present the results of a research project carried out in Spain, in which various instruments were designed to assess the media competence of students, teachers and parents. Its application has revealed that we are in an extraordinary moment to take advantage of media resources towards improving the educational process, although it is clear that the fact of being surrounded by media and technologies does not mean that we are competent in their use. This leads us to emphasize the importance of the inclusion of media education into the school curriculum from the earliest ages

La competencia mediática como reto para la educomunicación: instrumentos de evaluación

Technological advances make new resources available to educational agents in order to enhance learning, but their use requires developing basic competencies or skills in students and is a challenge to the entire educational community. In this context, media competence becomes fundamental for encouraging responsible, efficient and democratic use of media resources by citizens. Here we present the results of a research project carried out in Spain, in which various instruments were designed to assess the media competence of students, teachers and parents. Its application has revealed that we are in an extraordinary moment to take advantage of media resources towards improving the educational process, although it is clear that the fact of being surrounded by media and technologies does not mean that we are competent in their use. This leads us to emphasize the importance of the inclusion of media education into the school curriculum from the earliest ages

ANÁLISIS DEL VALOR DE MARCA DE LAS ENTIDADES FINANCIERAS: EL EFECTO HALO Y EL MODELO DE ELECCIÓN DISCRETA

El presente trabajo trata de cuantificar el valor de marca y el posicionamiento de las entidades financieras en dos mercados diferentes: consumidores finales y microempresas. Así mismo, se busca identificar las dimensiones de imagen de mayor peso a la hora de elegir a una entidad como la de mejor valoración global. A través del modelo de elección discreta y del análisis del efecto halo ,se comprueba la importancia del trato personal al cliente como la variable de mayor peso en la elección de marca. Además, se observa la mayor intensidad del efecto halo para las cajas de ahorros en el caso de los consumidores particulares. Sin embargo, en el segmento de microempresas, el valor de marca es superior para los bancos

Changes with age (from 0 to 37 D) in tibiae bone mineralization, chemical composition and structural organization in broiler chickens

Broiler chickens have an extreme physiology (rapid growth rates) that challenges the correct bone mineralization, being an interesting animal model for studying the development of bone pathologies. This work studies in detail how the mineralization, chemistry, and structural organization of tibiae bone in broiler chickens change with age during the first 5 wk (37 D) from hatching until acquiring the final weight for slaughter. During the early growth phase (first 2 wk), the rapid addition of bone tissue does not allow for bone organic matrix to fully mineralize and mature, and seems to be a critical period for bone development at which bone mineralization cannot keep pace with the rapid growth of bones. The low degree of bone mineralization and large porosity of cortical bone at this period might be responsible of leg deformation and/or other skeletal abnormalities commonly observed in these birds. Later, cortical bone porosity gradually decreases and the cortical bone became fully mineralized (65%) at 37 D of age. At the same time, bone mineral acquires the composition of mature bone tissue (decreased amount of carbonate, higher crystallinity, Ca/P = 1.68)

Multivariate brain functional connectivity through regularized estimators

Functional connectivity analyses are typically based on matrices containing bivariate measures of covariability, such as correlations. Although this has been a fruitful approach, it may not be the optimal strategy to fully explore the complex associations underlying brain activity. Here, we propose extending connectivity to multivariate functions relating to the temporal dynamics of a region with the rest of the brain. The main technical challenges of such an approach are multidimensionality and its associated risk of overfitting or even the non-uniqueness of model solutions. To minimize these risks, and as an alternative to the more common dimensionality reduction methods, we propose using two regularized multivariate connectivity models. On the one hand, simple linear functions of all brain nodes were fitted with ridge regression. On the other hand, a more flexible approach to avoid linearity and additivity assumptions was implemented through random forest regression. Similarities and differences between both methods and with simple averages of bivariate correlations (i.e., weighted global brain connectivity) were evaluated on a resting state sample of N = 173 healthy subjects. Results revealed distinct connectivity patterns from the two proposed methods, which were especially relevant in the age-related analyses where both ridge and random forest regressions showed significant patterns of age-related disconnection, almost completely absent from the much less sensitive global brain connectivity maps. On the other hand, the greater flexibility provided by the random forest algorithm allowed detecting sex-specific differences. The generic framework of multivariate connectivity implemented here may be easily extended to other types of regularized models

Electrochemical Detection of Iron in a Lixiviant Solution of Polluted Soil Using a Modified Glassy Carbon Electrode

This paper presents preliminary results on the modification of glassy carbon electrodes with Multiwall Carbon Nanotubes with or without Polyaniline and Pt nanoparticles as electrocatalytic materials for metallic pollutants detection. Electrodes were constructed and incorporated as amperometric detectors of ionic iron electroreduction using the Flow Injection Amperometric technique in aqueous solution. The results not only revealed the modified electrode with nanotubes, polyaniline and platinum nanoparticles were the most selective and sensitive, but also provided an electroanalytic tool to analyze iron in lixiviated samples of polluted soil. The proposed iron sensor exhibited a linear response between 0 and 10 mM with detection and quantification limits of 0.003 and 0.012 μM, respectively. The aqueous samples were taken from a lixiviated solution of polluted soil from Mineral de Pozos, Guanajuato, Mexico, to define the erosion grade of soil

Forest Fires, Land Use Changes and Their Impact on Hydrological Balance in Temperate Forests of Central Mexico

Temperate forests play a fundamental role in the provision, regulation, and support of hydrological environmental services, but they are subject to constant changes in land use (clearing, overgrazing, deforestation, and forest fires) that upset the hydrological balance. Through scenarios simulated with the Water Evaluation and Planning (WEAP) hydrological model, the present study analyzes the effects of forest fires and land use changes on the hydrological balance in the microwatersheds of central Mexico. The land use changes that took place between 1995 and 2021 were estimated, and projections based on the current scenario were made. Two trend scenarios were proposed for 2047: one with a positive trend (forest permanence) and the other with a negative trend (loss of cover from forest fires). The results show that with permanence or an increase in forest area, the surface runoff would decrease by 48.2%, increasing the base flow by 37% and the soil moisture by 2.3%. If forest is lost, surface runoff would increase up to 454%, and soil moisture would decrease by 27%. If the current forest decline trends continue, then there will be negative alterations in hydrological processes: a reduction in the interception of precipitation by the canopy and an increase in the velocity and flow of surface runoff, among others. The final result will be a lower amount of water being infiltrated into the soil and stored in the subsoil. The provision of hydrological environmental services depends on the maintenance of forest cover

Col·leccions singulars a les biblioteques de la Universitat Autònoma de Barcelona

Les biblioteques de la Universitat Autònoma de Barcelona són, com la mateixa institució, entitats amb una història curta; però, malgrat que van començar la seva activitat fa menys de cinquanta anys, els seus fons han assolit una importància considerable i superen en quantitat els de moltes universitats centenàries del nostre context. Les col·leccions de fons antics de les biblioteques de la UAB són, per aquesta mateixa raó, limitades, si bé se n'han anat creant algunes d'especialitzades d'importància i valor singulars. Aquest llibre pretén donar-les a conèixer al món universitari, però també al públic en general. Moltes són col·leccions úniques, fruit del treball persistent del personal bibliotecari, del professorat i de la generositat de moltes persones particulars, que han donat o llegat a la nostra universitat els seus arxius, les seves biblioteques personals o les seves col·leccions especialitzades. Aquestes col·leccions comprenen molts àmbits de les ciències i de les humanitats i, molt sovint, es tracta de col·leccions úniques al nostre país. Hi trobareu també un ampli ventall de tipologies documentals en llengües diverses, des dels mapes fins als audiovisuals, des de les revistes i diaris fins als cartells, des dels fons antics fins als més actuals, arxius personals i fons institucionals. Les biblioteques de la Universitat, a més d'inventariar i catalogar aquests fons documentals, també porten a terme una tasca constant de preservació i difusió, que sovint inclou la digitalització dels documents, que després es posen a l'abast del públic general mitjançant el dipòsit digital institucional (ddd.uab.cat)