University of Alcalá

About: University of Alcalá is a education organization based out in Alcalá de Henares, Spain. It is known for research contribution in the topics: Population & Context (language use). The organization has 10795 authors who have published 20718 publications receiving 410089 citations. The organization is also known as: University of Alcala & University of Alcala de Henares.

Cellular Characterization of Epidermal Growth Factor-expanded Free-floating Neurospheres

Abstract: Neural stem cells proliferate in liquid culture as cell clusters (neurospheres). This study was undertaken to characterize the epidermal growth factor (EGF)-expanded free-floating neurospheres derived from rat fetal striatum. We examined the ultrastructural and antigenic characteristics of these spheres. They consisted of two cell types, electron-dense and electron-lucent cells. Lucent cells were immunopositive to actin, vimentin, and nestin, whereas dense cells were immunopositive to actin, weakly positive to vimentin, and nestin-negative. Neurospheres contained healthy, apoptotic, and necrotic cells. Healthy cells were attached to each other by adherens junctions. They showed many pseudopodia and occasionally a single cilium. Sphere cells showed phagocytic capability because healthy cells phagocytosed the cell debris derived from dead cells in a particular process that involves the engulfment of dying cells by cell processes from healthy cells. Sphere cells showed a cytoplasmic and a nuclear pool of fib...

African burned area and fire carbon emissions are strongly impacted by small fires undetected by coarse resolution satellite data.

Abstract: Fires are a major contributor to atmospheric budgets of greenhouse gases and aerosols, affect soils and vegetation properties, and are a key driver of land use change. Since the 1990s, global burned area (BA) estimates based on satellite observations have provided critical insights into patterns and trends of fire occurrence. However, these global BA products are based on coarse spatial-resolution sensors, which are unsuitable for detecting small fires that burn only a fraction of a satellite pixel. We estimated the relevance of those small fires by comparing a BA product generated from Sentinel-2 MSI (Multispectral Instrument) images (20-m spatial resolution) with a widely used global BA product based on Moderate Resolution Imaging Spectroradiometer (MODIS) images (500 m) focusing on sub-Saharan Africa. For the year 2016, we detected 80% more BA with Sentinel-2 images than with the MODIS product. This difference was predominately related to small fires: we observed that 2.02 Mkm2 (out of a total of 4.89 Mkm2) was burned by fires smaller than 100 ha, whereas the MODIS product only detected 0.13 million km2 BA in that fire-size class. This increase in BA subsequently resulted in increased estimates of fire emissions; we computed 31 to 101% more fire carbon emissions than current estimates based on MODIS products. We conclude that small fires are a critical driver of BA in sub-Saharan Africa and that including those small fires in emission estimates raises the contribution of biomass burning to global burdens of (greenhouse) gases and aerosols.

High rate of didanosine-related mitochondrial toxicity in HIV/HCV-coinfected patients receiving ribavirin.

Abstract: BackgroundNucleoside analogues may induce mitochondrial toxicity, particularly didanosine. Ribavirin increases didanosine exposure, which might be clinically relevant when coadministered in HIV/HCV...

Aggregation of Variables and Applications to Population Dynamics

Abstract: 1 IRD UR Geodes, Centre IRD de l’Ile de France, 32, Av. Henri Varagnat, 93143 Bondy cedex, France pierre.auger@bondy.ird.fr 2 Departamento de Matematicas, Universidad de Alcala, 28871 Alcala de Henares, Madrid, Spain rafael.bravo@uah.es 3 Laboratoire de Microbiologie, Geochimie et d’Ecologie Marines, UMR 6117, Centre d’Oceanologie de Marseille (OSU), Universite de la Mediterranee, Case 901, Campus de Luminy, 13288 Marseille Cedex 9, France Jean-Christophe.Poggiale@univmed.fr 4 Departamento de Matematicas, E.T.S.I. Industriales, U.P.M., c/ Jose Gutierrez Abascal, 2, 28006 Madrid, Spain esanchez@etsii.upm.es 5 IXXI, ENS Lyon, 46 allee d’Italie, 69364 Lyon cedex 07, France tri.nguyen-huu@ens-lyon.fr

Human and non-human determinants of forest composition in southern Spain: evidence of shifts towards cork oak dominance as a result of management over the past century

Abstract: 13 pages, 4 figures, 2 tables, 70 references. We are grateful to the Andalusian Government (Consejeria de Medio Ambiente), and to Felipe Oliveros and the staff of Los Alcornocales Park for the facilities to compile forest inventory information and for visit permits. We thank Javier Quijada and Jose Manuel Moreira of REDIAM, and Jose A. Villanueva of the Ministry of Environment, for providing, respectively, environmental and SSFI data, as well as Francisco Rodriguez, Sara Rodriguez, and Carlota Martinez for assistance at various stages. Daniel Montoya, Drew Purves, James Aronson. Historical forest management plans were consulted in the archive of the Direccion General para la Biodiversidad (Madrid).