90 research outputs found
Diseño de investigación de una herramienta para el análisis de perfiles de personalidad para estudiantes de primer año de la Universidad de San Carlos de Guatemala
Diseñar una herramienta de análisis de datos para optimizar el proceso de estudio de resultados de las pruebas de personalidad de las distintas facultades de la Universidad de San Carlos de Guatemala zona 12, así analizar la información e identificar que perfiles predominan por facultades, así interpretar la información de tal manera que sea intuitiva a las personas que están evaluando y definir qué relaciones y diferencias tienen los perfiles entre facultades
Natural attenuation of residual heavy metal contamination in soils affected by the Aznalcóllar mine spill
NOTICE: this is the author’s version of a work that was accepted for publication in Journal of Environmental Management. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Environmental Management 92.8 (2011): 2069-2075 http://dx.doi.org/10.1016/j.jenvman.2011.03.030Non-amended soils affected by pyritic sludge residues were monitored for 7 years to assess the long-term natural attenuation ability of these soils. The decrease in both the total concentration of elements (particularly As) and (NH4)2SO4-extractable fractions of Mn, Cu, Zn, and Cd below maximum permissible levels indicate a successful natural ability to attenuate soil pollution. Soil acidification by pyrite oxidation and rainfall-enhanced leaching were the largest contributors to the reduction of high (Mn, Cu, Zn and Cd) and low (Fe, Al, and As) availability metals. Periodic use of correlation and spatial distribution analysis was useful in monitoring elemental dispersion and soil property/element relationshipsFinancial support from the Spanish MICINN (CTM 2007-66401-CO2-02/TECNO; CTM 2004-06715-CO2-01), and from Comunidad de Madrid (EIADES S2009/AMB-1478) is acknowledge
Biodiversity of ecosystems in an arid setting: The late Albian plant communities and associated biota from eastern Iberia
Deserts are stressful environments where the living beings must acquire different strategies to survive due to the water stress conditions. From the late Albian to the early Cenomanian, the northern and eastern parts of Iberia were the location of the desert system represented by deposits assigned to the Utrillas Group, which bear abundant amber with numerous bioinclusions, including diverse arthropods and vertebrate remains. In the Maestrazgo Basin (E Spain), the late Albian to early Cenomanian sedimentary succession represents the most distal part of the desert system (fore-erg) that was characterised by an alternation of aeolian and shallow marine sedimentary environments in the proximity of the Western Tethys palaeo-coast, with rare to frequent dinoflagellate cysts. The terrestrial ecosystems from this area were biodiverse, and comprised plant communities whose fossils are associated with sedimentological indicators of aridity. The palynoflora dominated by wind-transported conifer pollen is interpreted to reflect various types of xerophytic woodlands from the hinterlands and the coastal settings. Therefore, fern and angiosperm communities abundantly grew in wet interdunes and coastal wetlands (temporary to semi-permanent freshwater/salt marshes and water bodies). In addition, the occurrence of low-diversity megafloral assemblages reflects the existence of coastal salt-influenced settings. The palaeobotanical study carried out in this paper which is an integrative work on palynology and palaeobotany, does not only allow the reconstruction of the vegetation that developed in the mid-Cretaceous fore-erg from the eastern Iberia, in addition, provides new biostratigraphic and palaeogeographic data considering the context of angiosperm radiation as well as the biota inferred in the amber-bearing outcrops of San Just, Arroyo de la Pascueta and La Hoya (within Cortes de Arenoso succesion). Importantly, the studied assemblages include Afropollis, Dichastopollenites, Cretacaeiporites together with pollen produced by Ephedraceae (known for its tolerance to arid conditions). The presence of these pollen grains, typical for northern Gondwana, associates the Iberian ecosystems with those characterising the mentioned region.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEMinisterio de Ciencia, Innovacio ́n y UniversidadesIGME-CSICSecretaria d’Universitats i Recerca de la Generalitat de CataloniaEuropean Social Fundpu
Human colon-derived soluble factors modulate gut microbiota composition
This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).-- et al.The commensal microbiota modulates immunological and metabolic aspects of the intestinal mucosa contributing to development of human gut diseases including inflammatory bowel disease. The host/microbiota interaction often referred to as a crosstalk, mainly focuses on the effect of the microbiota on the host neglecting effects that the host could elicit on the commensals. Colonic microenvironments from three human healthy controls (obtained from the proximal and distal colon, both in resting conditions and after immune - IL-15-and microbiota - LPS-in vitro challenges) were used to condition a stable fecal population. Subsequent 16S rRNA gene-based analyses were performed to study the effect induced by the host on the microbiota composition and function. Non-supervised principal component analysis (PCA) showed that all microbiotas, which had been conditioned with colonic microenvironments clustered together in terms of relative microbial composition, suggesting that soluble factors were modulating a stable fecal population independently from the treatment or the origin. Our findings confirmed that the host intestinal microenvironment has the capacity to modulate the gut microbiota composition via yet unidentified soluble factors. These findings indicate that an appropriate understanding of the factors of the host mucosal microenvironment affecting microbiota composition and function could improve therapeutic manipulation of the microbiota composition.BS and AH were recipients of a Ramón y Cajal postdoctoral contract and a FPI grant, respectively, from the Spanish Ministry of Economy and Competitiveness. The authors gratefully acknowledge the support of the Biotechnology and Biological Sciences Research Council (BBSRC). This research was funded by the BBSRC Institute Strategic Programme for Gut Health and Food Safety BB/J004529/1. This research was also funded by Grants AGL2010-14952 and AGL2013-44039-R from the Spanish “Plan Estatal de I + D + i,” and by Grant EM2014/046 from the “Plan galego de investigación, innovación e crecemento 2011-2015.”Peer Reviewe
Modelling the vertical distribution of canopy fuel load using national forest inventory and low-density airbone laser scanning data
[EN] The fuel complex variables canopy bulk density and canopy base height are often used to predict crown fire initiation and spread. Direct measurement of these variables is impractical, and they are usually estimated indirectly by modelling. Recent advances in predicting crown fire behaviour require accurate estimates of the complete vertical distribution of canopy fuels. The objectives of the present study were to model the vertical profile of available canopy fuel in pine stands by using data from the Spanish national forest inventory plus lowdensity airborne laser scanning (ALS) metrics. In a first step, the vertical distribution of the canopy fuel load was modelled using the Weibull probability density function. In a second step, two different systems of models were fitted to estimate the canopy variables defining the vertical distributions; the first system related these variables to stand variables obtained in a field inventory, and the second system related the canopy variables to airborne laser scanning metrics. The models of each system were fitted simultaneously to compensate the effects of the inherent cross-model correlation between the canopy variables. Heteroscedasticity was also analyzed, but no correction in the fitting process was necessary. The estimated canopy fuel load profiles from field variables explained 84% and 86% of the variation in canopy fuel load for maritime pine and radiata pine respectively; whereas the estimated canopy fuel load profiles from ALS metrics explained 52% and 49% of the variation for the same species. The proposed models can be used to assess the effectiveness of different forest management alternatives for reducing crown fire hazardSIFunding was provided by projects DIABOLO (H2020 GA 633464) and GEPRIF (RTA 2014-00011-c06-04). The funders did not participate in designing the study, data collection and analysis, decision to publish or preparation of the manuscript. We are grateful to the Galician Government and European Social Fund (Official Journal of Galicia – DOG n° 52, 17/03/2014, p. 11343, exp: POS-A/2013/049) for financing the postdoctoral research stays of Dr Eduardo González-Ferreiro at different institutions. Copyright of LiDAR data, Instituto Geográfico Nacional-Xunta de Galici
Modelling the vertical distribution of canopy fuel load using national forest inventory and low-density airbone laser scanning data
The fuel complex variables canopy bulk density and canopy base height are often used to
predict crown fire initiation and spread. Direct measurement of these variables is impractical,
and they are usually estimated indirectly by modelling. Recent advances in predicting
crown fire behaviour require accurate estimates of the complete vertical distribution of canopy
fuels. The objectives of the present study were to model the vertical profile of available
canopy fuel in pine stands by using data from the Spanish national forest inventory plus lowdensity
airborne laser scanning (ALS) metrics. In a first step, the vertical distribution of the
canopy fuel load was modelled using the Weibull probability density function. In a second
step, two different systems of models were fitted to estimate the canopy variables defining
the vertical distributions; the first system related these variables to stand variables obtained
in a field inventory, and the second system related the canopy variables to airborne laser
scanning metrics. The models of each system were fitted simultaneously to compensate the
effects of the inherent cross-model correlation between the canopy variables. Heteroscedasticity
was also analyzed, but no correction in the fitting process was necessary. The estimated
canopy fuel load profiles from field variables explained 84% and 86% of the variation
in canopy fuel load for maritime pine and radiata pine respectively; whereas the estimated
canopy fuel load profiles from ALS metrics explained 52% and 49% of the variation for the
same species. The proposed models can be used to assess the effectiveness of different
forest management alternatives for reducing crown fire hazardWe are grateful to the Galician Government and European Social Fund (Official Journal of Galicia—DOG n° 52, 17/03/2014, p. 11343, exp: POS-A/2013/049) for financing the postdoctoral research stays of Dr Eduardo González-Ferreiro at different institutions. Copyright of LiDAR data, Instituto Geográfico Nacional-Xunta de GaliciaS
Dinosaur bonebed amber from an original swamp forest soil
Dinosaur bonebeds with amber content, yet scarce, offer a superior wealth and quality of data on ancient terrestrial ecosystems. However, the preserved palaeodiversity and/or taphonomic characteristics of these exceptional localities had hitherto limited their palaeobiological potential. Here, we describe the amber from the Lower Cretaceous dinosaur bonebed of Ariño (Teruel, Spain) using a multidisciplinary approach. Amber is found in both a root layer with amber strictly in situ and a litter layer mainly composed of aerial pieces unusually rich in bioinclusions, encompassing 11 insect orders, arachnids, and a few plant and vertebrate remains, including a feather. Additional palaeontological data—charophytes, palynomorphs, ostracods— are provided. Ariño arguably represents the most prolific and palaeobiologically diverse locality in which fossiliferous amber and a dinosaur bonebed have been found in association, and the only one known where the vast majority of the palaeontological assemblage suffered no or low-grade pre-burial transport. This has unlocked unprecedentedly complete and reliable palaeoecological data out of two complementary windows of preservation—the bonebed and the amber—from the same site.European Regional Development Fund (FEDER)Ministerio de Ciencia e Innovación (MICINN)/FEDERMinisterio de Economía y Competitividad (MINECO)/FEDERGeneralitat de CatalunyaGeneralitat de Catalunya/FEDERMMinisterio de Ciencia e Innovación (MICINN)Oxford UniversityAustrian Academy of SciencesUniversité de TunisGeneralitat ValencianaDepto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEpu
- …