251 research outputs found

    Comparative geometrical study of fault-propagation folds associated with lateral tips of thrusts

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    This work examines the geometry of two examples of fault-propagation folds related to the lateral termination of thrusts. In spite of their differences in age (Variscan and Alpine) and composition of the involved rocks (metamorphic or sedimentary), the geometry of the resulting folds is quite similar, indicating that are universal the mechanisms responsible for these structure

    Geotechnical characteristics of the soils of Huelva town: index properties and consolidation test

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    This paper shows the preliminary results of a laboratory geotechnical test for the identification and determination of consolidation properties of the soils of Huelva. The fine-grained soils (Arcillas de Gibraleón, Arenas de Huelva and Arenas de Bonares units) have a high consistency. These are over-consolidated soils which have few compressibilities. The Arcillas de Gibraleón Unit presents expansive clay mineral

    Seismotectonics related to the Azores – Gibraltar Fracture Zone: Analysis of the February 12th 2007 earthquake, SW Gorringe Bank

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    This work deals with the analysis of the seismicity and tectonic evolution of the eastern end of the Azores – Gibraltar Fracture Zone. The location of the main seismogenetic areas in this region is related to the complex geometry of the boundary between the Iberian and African lithospheric plates. To the west of the San Vicente Cape the seismicity can be related to a local compression at the Gorringe Bank. A detailed seismotectonic analysis allows the geological interpretation of the position of the hypocenter for the 12th February 2007 earthquake. It had Mw 6.0 and was placed on a fault having a NNE-SSW strike and a high dip to NW. The fault shows an oblique displacement (sinistral) and locates in the margin of the Horseshoe abyssal basin. Displacement along this fault is here tentatively related to complex deformation in the outer swell of an incipient downgoing plate. This can be the first indication of the beginning of subduction of the northern part of the African plate under the continental margin of Iberia. On the other hand, an analysis of the location of earthquakes having Mw >6.0 generated to the SW of the San Vicente Cape and the estimated isoseismal map has been made. It can be noted the importance of the uppermost crustal materials on the seismic intensity measurement. Sea waves resulting from these earthquakes and measured in the littoral of the Huelva province have an average velocity of propagation of approximately 600 km/

    Cortical fracturing inferred from active and passive seismicity techniques: Neogene extension in the "forebulge" of the Guadalquivir Basin

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    La aplicación de técnicas de sismicidad pasiva y activa ha permitido observar variaciones en la frecuencia fundamental del suelo en una transversal a los estuarios Odiel y Tinto (Huelva). Los valores más bajos (0,27-0,29 Hz) están en el extremo oriental de la transversal, en las proximidades de Mazagón. Los valores más altos (0,83-1,06 Hz) se localizan en el extremo occidental de la transversal, al oeste del Odiel. El “basamento rocoso” (mecánico) es identificado como el techo del Complejo Basal Transgresivo (calizas neógenas). El zócalo paleozoico estará situado 10-20 metros por debajo de dichas calizas. Se interpreta que fallas extensionales NNE-SSO acomodan la extensión de la corteza terrestre durante el Neógeno en relación con el “forebulge” de la Cuenca del GuadalquivirThe application of passive and active seismicity techniques has allowed us to observe variations in the fundamental frequency of the soil in a transversal in the estuaries Odiel and Tinto (Huelva). The lowest values (0.27-0.29 Hz) are at the eastern end of the transversal, near Mazagón. The highest values (0.83-1.06 Hz) are located at the western end of the transversal, west of Odiel. The “rocky basement” (mechanical) is identified as the roof of the transgressive basal complex (limestones of Neogene age). The Paleozoic basement will be located 10-20 meters below these limestones. It is interpreted that NNE-SSO extensional faults accommodate the extension of the earth’s crust during the Neogen in relation to the “forebulge” of the Guadalquivir Basi

    The CARBA-MAP study: national mapping of carbapenemases in Spain (2014–2018)

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    Introduction:Infections caused by carbapenem-resistant Enterobacterales (CRE) and carbapenem-resistant Pseudomonas aeruginosa, including isolates producing acquired carbapenemases, constitute a prevalent health problem worldwide. The primary objective of this study was to determine the distribution of the different carbapenemases among carbapenemase-producing Enterobacterales (CPE, specifically Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae complex, and Klebsiella aerogenes) and carbapenemase-producing P. aeruginosa (CPPA) in Spain from January 2014 to December 2018.Methods: A national, retrospective, cross-sectional multicenter study was performed. The study included the first isolate per patient and year obtained from clinical samples and obtained for diagnosis of infection in hospitalized patients. A structured questionnaire was completed by the participating centers using the REDCap platform, and results were analyzed using IBM SPSS Statistics 29.0.0.Results: A total of 2,704 carbapenemase-producing microorganisms were included, for which the type of carbapenemase was determined in 2692 cases: 2280 CPE (84.7%) and 412 CPPA (15.3%), most often using molecular methods and immunochromatographic assays. Globally, the most frequent types of carbapenemase in Enterobacterales and P. aeruginosa were OXA-48-like, alone or in combination with other enzymes (1,523 cases, 66.8%) and VIM (365 cases, 88.6%), respectively. Among Enterobacterales, carbapenemase-producing K. pneumoniae was reported in 1821 cases (79.9%), followed by E. cloacae complex in 334 cases (14.6%). In Enterobacterales, KPC is mainly present in the South and South-East regions of Spain and OXA-48-like in the rest of the country. Regarding P. aeruginosa, VIM is widely distributed all over the country. Globally, an increasing percentage of OXA-48-like enzymes was observed from 2014 to 2017. KPC enzymes were more frequent in 2017–2018 compared to 2014–2016.Discussion: Data from this study help to understand the situation and evolution of the main species of CPE and CPPA in Spain, with practical implications for control and optimal treatment of infections caused by these multi-drug resistant organisms

    A colorectal cancer susceptibility new variant at 4q26 in the Spanish population identified by genome-wide association analysis

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    BACKGROUND: Non-hereditary colorectal cancer (CRC) is a complex disorder resulting from the combination of genetic and non-genetic factors. Genome-wide association studies (GWAS) are useful for identifying such genetic susceptibility factors. However, the single loci so far associated with CRC only represent a fraction of the genetic risk for CRC development in the general population. Therefore, many other genetic risk variants alone and in combination must still remain to be discovered. The aim of this work was to search for genetic risk factors for CRC, by performing single-locus and two-locus GWAS in the Spanish population. RESULTS: A total of 801 controls and 500 CRC cases were included in the discovery GWAS dataset. 77 single nucleotide polymorphisms (SNP)s from single-locus and 243 SNPs from two-locus association analyses were selected for replication in 423 additional CRC cases and 1382 controls. In the meta-analysis, one SNP, rs3987 at 4q26, reached GWAS significant p-value (p = 4.02×10(-8)), and one SNP pair, rs1100508 CG and rs8111948 AA, showed a trend for two-locus association (p = 4.35×10(-11)). Additionally, our GWAS confirmed the previously reported association with CRC of five SNPs located at 3q36.2 (rs10936599), 8q24 (rs10505477), 8q24.21(rs6983267), 11q13.4 (rs3824999) and 14q22.2 (rs4444235). CONCLUSIONS: Our GWAS for CRC patients from Spain confirmed some previously reported associations for CRC and yielded a novel candidate risk SNP, located at 4q26. Epistasis analyses also yielded several novel candidate susceptibility pairs that need to be validated in independent analyses

    Anti-tumour necrosis factor discontinuation in inflammatory bowel disease patients in remission: study protocol of a prospective, multicentre, randomized clinical trial

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    Background: Patients with inflammatory bowel disease who achieve remission with anti-tumour necrosis factor (anti-TNF) drugs may have treatment withdrawn due to safety concerns and cost considerations, but there is a lack of prospective, controlled data investigating this strategy. The primary study aim is to compare the rates of clinical remission at 1?year in patients who discontinue anti-TNF treatment versus those who continue treatment. Methods: This is an ongoing, prospective, double-blind, multicentre, randomized, placebo-controlled study in patients with Crohn?s disease or ulcerative colitis who have achieved clinical remission for ?6?months with an anti-TNF treatment and an immunosuppressant. Patients are being randomized 1:1 to discontinue anti-TNF therapy or continue therapy. Randomization stratifies patients by the type of inflammatory bowel disease and drug (infliximab versus adalimumab) at study inclusion. The primary endpoint of the study is sustained clinical remission at 1?year. Other endpoints include endoscopic and radiological activity, patient-reported outcomes (quality of life, work productivity), safety and predictive factors for relapse. The required sample size is 194 patients. In addition to the main analysis (discontinuation versus continuation), subanalyses will include stratification by type of inflammatory bowel disease, phenotype and previous treatment. Biological samples will be obtained to identify factors predictive of relapse after treatment withdrawal. Results: Enrolment began in 2016, and the study is expected to end in 2020. Conclusions: This study will contribute prospective, controlled data on outcomes and predictors of relapse in patients with inflammatory bowel disease after withdrawal of anti-TNF agents following achievement of clinical remission. Clinical trial reference number: EudraCT 2015-001410-1
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