198 research outputs found

    Occidente, una civilización en declive

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    Mixed-dimensional geometric multigrid methods for single-phase flow in fractured porous media

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    This paper deals with the efficient numerical solution of single-phase flow problems in fractured porous media. A monolithic multigrid method is proposed for solving two-dimensional arbitrary fracture networks with vertical and/or horizontal possibly intersecting fractures. The key point is to combine two-dimensional multigrid components (smoother and intergrid transfer operators) in the porous matrix with their one-dimensional counterparts within the fractures, giving rise to a mixed-dimensional geometric multigrid method. This combination seems to be optimal since it provides an algorithm whose convergence matches the multigrid convergence factor for solving the Darcy problem. Several numerical experiments are presented to demonstrate the robustness of the monolithic mixed-dimensional multigrid method with respect to the permeability of the fractures, the grid size, and the number of fractures in the network.The work of the first and fourth authors was supported by Spanish project PGC2018-099536-A-I00 (MCIU/AEI/FEDER, UE). The work of the second author was supported by the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement 705402, POROSOS. The work of the third author was partially supported by the Spanish project FEDER/MCYT MTM2016-75139-R. The work of the fourth author was supported by the DGA (Grupo de referencia APEDIF, ref. E24 17R)

    Multigrid solvers for multipoint flux approximations of the Darcy problem on rough quadrilateral grids

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    In this work, an efficient blackbox-type multigrid method is proposed for solving multipoint flux approximations of the Darcy problem on logically rectangular grids. The approach is based on a cell-centered multigrid algorithm, which combines a piecewise constant interpolation and the restriction operator by Wesseling/Khalil with a line-wise relaxation procedure. A local Fourier analysis is performed for the case of a Cartesian uniform grid. The method shows a robust convergence for different full tensor coefficient problems and several rough quadrilateral grids.Francisco J. Gaspar has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Skłodowska–Curie grant agreement no. 705402, POROSOS. The work of Laura Portero is supported by the Spanish project MTM2016-75139-R (AEI/FEDER, UE) and the Young Researchers Programme 2018 from the Public University of Navarre. Andrés Arrarás acknowledges support from the Spanish project PGC2018-099536-A-I00 (MCIU/AEI/FEDER, UE) and the Young Researchers Programme 2018 from the Public University of Navarre. The work of Carmen Rodrigo is supported by the Spanish project PGC2018-099536-A-I00 (MCIU/AEI/FEDER, UE) and the DGA (Grupo de referencia APEDIF, ref. E24_17R)

    The persistence of red deer (Cervus elaphus) in the human diet during the Lower Magdalenian in northern Spain: Insights from El Cierro cave (Asturias, Spain)

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    he dominance of red deer in Magdalenian records in Cantabrian Spain is a well-studied issue. Given the great accumulations of this species in those deposits, researchers have offered diverse interpretations of the phenomenon, related to ecology, orography or ethology. However, fewer papers carry out comparative intra-site analysis, which is able to document the existence of changes or continuities in the subsistence strategies at an archaeological site. The aim of this paper is to present the results of the archaeozoological analysis of Levels F and G in El Cierro cave (Asturias, Spain), both of them dated during Greenland Stadial 2, in the Lower Magdalenian (15,460 ± 75 and 15,580 ± 75 BP, respectively). Similar percentages of mammals have been documented in the two levels, as well as the same meat and fat consumption and processing strategies. Thus, this paper intends to determine how much energy red deer supplied to the diet of the humans that inhabited El Cierro, in comparison with other hunted and consumed fauna during the Lower Magdalenian. This study highlights the continuity of exploitation patterns of faunal resources in El Cierro cave during the Lower Magdalenian. This continuity is specifically seen in red deer, since the geographic characteristics of the Sella Valley, the abundance of the biotype, and the economic profitability of this species made it the main resource of animal origin for the hunter-gatherers at that site.This research was undertaken in the context of the Spanish projects HAR2014-51830-P funded by the Programa Nacional de Humanidades in the R&D Plan of the Spanish Ministry of Science and Innovation, and HAR2017-82557-P, funded by the Programa Estatal de Fomento de la Investigación Científica y Técnica de Excelencia, of the Spanish Ministry of Economy, Industry and Competitiveness, and PhD scholarship Junta de Castilla y León and Fondo Social Europeo (R. Portero)

    Radiocarbon dates for the late Pleistocene and Early Holocene occupations of Cova Rosa (Ribadesella, Asturias, Spain)

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    Four excavations have been performed at the archaeological site of Cova Rosa (Asturias, Cantabrian Spain): three of them in the second half of last century and the other in this decade. Although little of the archaeological material found in those excavations has been published, here we attempt the stratigraphic correlation of sections revealed by the different excavations and we present 22 new radiocarbon dates for bones and marine shells, built in a Bayesian statistical model. This has enabled the documentation of occupations that mainly took place during the Last Glacial period, in the Solutrean (middle and upper phases) and Magdalenian (archaic, lower, and upper phases), and also in the early Holocene (Mesolithic). These occupations are compared with the record at other sites in Cantabrian Spain in general and in Asturias, in particular.Introduction Cova Rosa Cave - Geographical and Geological Setting - History of Research - Stratigraphy Radiocarbon dates at Cova Rosa - Method - Validity Analysis - Results and Critical Assessment - Solutrean - Magdalenian - Mesolithic Discussion: 14C chronology of Cova Rosa Conclusion

    Epifisiolisis de cabeza de radio asociadas a luxación de codo y reducción espontánea

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    Realizamos un estudio retrospectivo de 10 casos de la epifisiolisis de cabeza de radio ocurridas durante el periodo 1992 a 1997, con un desplazamiento mayor de 60º que según los criterios de O'Brien corresponderían a un grado III. De todas las revisadas seleccionamos 6 casos en los que había una angulación mayor de 90º, creemos ocurren después de luxación o reducción espontánea de luxación de codo; por ser las más frecuentes, las que más problemas presentan en el tratamiento y las que producen más secuelas. Nuestro objetivo es valorar los resultados obtenidos con nuestros tratamientos y realizar una revisión bibliográfica.We have done a retrospective study of ten cases of radial head epiphysiolysis occurred between 1992 and 1997, displaced more than 60º. (O'Brien's grade III). Amongst them we have selected those which were displaced more than 90º (six cases) probably occurred after an elbow luxation or after the spontaneous reduction of an elbow luxation; because the are more infrequent, more troublesome and they give more secuelae. Our aim is to evaluate the results obtained with the treatment and to review the literature

    Transcriptomic identification of miR-205 target genes potentially involved in metastasis and survival of cutaneous malignant melanoma

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    Cutaneous melanoma is an aggressive neoplasm and is responsible for the majority of skin cancer deaths. Several miRNAs are involved in melanoma tumor progression. One of them is miR-205, the loss of which contributes to the development of melanoma metastasis. We evaluated whole-genome mRNA expression profiling associated with different miR-205 expression levels in melanoma cells. Differential expression analysis identified 243 differentially expressed transcripts including inositol polyphosphate 5'-phosphatase-like protein-1 (INPPL1) and BTB/POZ Domain-Containing Protein 3 (BTBD3). INPPL1 and BTBD3 were downregulated when melanoma cells expressed miR-205, indicating that these genes are potential miR-205 targets. Additionally, the target prediction algorithm TargetScan revealed that INPPL1 and BTBD3 genes had predicted target sites of miR-205 in their 3'UTRs and functional analysis demonstrated that these genes were directly linked to miR-205. Interestingly, our clinical data showed that INPPL1 was significantly associated with lymph node metastasis-free survival (LNMFS), distant metastasis-free survival (DMFS) and melanoma specific survival (MSS). This study supports INPPL1 as a miR-205 target gene and, therefore, that the involvement of miR-205 in the metastatic dissemination of malignant melanoma is, at least in part, via INPPL1

    Approach to the Spanish continental Neogene synthesis and paleoclimatic interpretation

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    Integrated studies on Neogene geology have been scarce in Spain, but attemps to stratigraphic and sedimentological analysis of continental Tertiary basins have increased considerably lately. The large extent of Neogene basins in Spain, the good quality of the outcrops and the abundance of fossil provide an excellent basis for this kind of studies

    La Cuevona de Avín (Avín, Asturias, North Spain): A new Late Pleistocene site in the lower valley of the River Güeña

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    The archaeological investigations carried out in the last twenty years in the Lower Valley of the River Güeña (Asturias, central part of northern Spain) have documented different prehistoric sites, particularly with Middle and Upper Palaeolithic occupations. This paper presents the first results of the archaeological excavation carried out in the cave of La Cuevona de Avín. From the systematic study of the biotic and abiotic remains, a total of three occupation phases (Phases 1 to 3) have been determined, dated in the Late Pleistocene. The lithic studies indicate the use of local raw materials (mainly quartzite), but also regional ones (different types of flint) in the whole sequence. Retouched implements are typologically representative only during the Upper Magdalenian (Phase II) and use-wear analysis indicates the manufacture and use of artefacts in situ during this phase. Archaeozoological studies reveal continuity in subsistence strategies throughout the sequence, noting specialization in red deer hunting during the Azilian (Phase I), and more diversified prey in the older phases of the sequence. © 2022 The Author(s

    Cognitive impairment in patients with Fibromyalgia syndrome as assessed by the Mini-Mental State Examination

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    <p>Abstract</p> <p>Background</p> <p>This study evaluated the frequency of cognitive impairment in patients with Fibromyalgia syndrome (FMS) using the Mini Mental State Examination (MMSE).</p> <p>Methods</p> <p>We analyzed baseline data from all 46 patients with FMS and 92 age- and sex-matched controls per diagnosis of neuropathic (NeP) or mixed pain (MP) selected from a larger prospective study.</p> <p>Results</p> <p>FMS had a slight but statistically significant lower score in the adjusted MMSE score (26.9; 95% CI 26.7-27.1) than either NeP (27.3; 95% CI 27.2-27.4) or MP (27.3; 27.2-27.5). The percentage of patients with congnitive impairment (adjusted MMSE ≤ 26) was numerically higher in FMS (15%; 95% CI 6.3-29) compared with NeP (5%; 95% CI 1.8-12.2) or MP (5%; 95% CI 1.8-12.2) and higher than in the same age stratum of the general population (0.05%).</p> <p>Conclusions</p> <p>Compared with the population reference value, patients with FMS showed high frequency of cognitive impairment.</p
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