1,545 research outputs found

    Quadratic Maps in Two Variables on Arbitrary Fields

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    Let F\mathbb{F} be a field of characteristic different from 22 and 33, and let VV be a vector space of dimension 22 over F\mathbb{F}. The generic classification of homogeneous quadratic maps f ⁣:VVf\colon V\to V under the action of the linear group of VV, is given and efficient computational criteria to recognize equivalence are provided.Comment: 12 pages, no figure

    Carbonatos en suelos de la zona oriental de Gran Canaria

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    The study of three soil profiles in the aridic-xeric zone of Las Palmas island showed that: petrocalcic horizons are formed in pyroclastic episodes; these horizons are generally thick; the xeric zone frequently have polycyclic profiles and their carbonates have complex mineralogy; underlain basaltic rocks are scantly altered, and their joints are frequently filled by carbonates. These facts suggest that the development of these profiles is mostly Pleistocene, and the diffuse carbonates accumulation in depth obstructs the assessment of carbonatation processes

    Genomic Evolution of Two Acinetobacter baumannii Clinical Strains from ST-2 Clones Isolated in 2000 and 2010 (ST-2_clon_2000 and ST-2_clon_2010)

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    Acinetobacter baumannii is a successful nosocomial pathogen due to its ability to persist in hospital environments by acquiring mobile elements such as transposons, plasmids, and phages. In this study, we compared two genomes of A. baumannii clinical strains isolated in 2000 (ST-2_clon_2000) and 2010 (ST-2_clon_2010) from GenBank project PRJNA308422

    Evidence for coseismic events of recurrent prehistoric deformation along the Alhama de Murcia fault, southeastern Spain

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    The Alhama de Murcia fault is a 85 km long oblique-slip fault, and is related to historical and instrumental seismic activity. A paleoseismic analysis of the Lorca-Totana sector of the fault containing MSK I=VIII historical earthquakes was made in order to identify and quantify its seismic potential. We present 1) the results of the neotectonic, structural and geomorphological analyses and, 2) the results of trenching. In the study area, the Alhama de Murcia fault forms a depressed corridor between two strands, the northwestern fault with morphological and structural features of a reverse component of slip, bounding the La Tercia range to the South, and the southeastern fault strand with evidence of sinistral oblique strike-slip movement. The offset along this latter fault trapped the sediments in transit from the La Tercia range towards the Guadalentín depression. The most recent of these sediments are arranged in three generations of alluvial fans and terraces. The first two trenches were dug in the most recent sediments across the southeastern fault strand. The results indicate a coseismic reverse fault deformation that involved the sedimentary sequence up to the intermediate alluvial fan and the Holocene terrace deposits. The sedimentary evolution observed in the trenches suggests an event of temporary damming of the Colmenar creek drainage to the South due to uplifting of the hanging wall during coseismic activation of the fault. Trench, structural and sedimentological features provide evidence of at least three coseismic events, which occurred after 125,000 yr. The minimum vertical slip rate along the fault is 0.06 mm/yr and the average recurrence period should not exceed 40,000 yr in accordance with the results obtained by fan topographic profiling. Further absolute dating is ongoing to constrain these estimates.Se presentan los primeros resultados del estudio paleosísmico del sector Lorca-Totana (con terremotos históricos de I=VIII) de la falla de Alhama de Murcia, de deslizamiento direccional oblícuo sinestroso, para caracterizar su potencial sísmico. Esto incluye: 1) resultados del estudio neotectónico, estructural y geomorfológico y 2) primeros resultados obtenidos en trincheras. El área estudiada muestra dos zonas de falla, la noroeste, que limita la sierra de la Tercia, con morfología y estructuras típicas de movimiento inverso, y la sureste con evidencias de deslizamiento direccional sinestroso, separadas por un corredor deprimido. La actividad de estas fallas ha atrapado en el corredor gran cantidad de sedimentos en su transporte hacia la depresión del Guadalentín, los más recientes de los cuales se organizan en tres generaciones de abanicos aluviales y terrazas. Las dos trincheras se ex c avaron en los sedimentos de la generación intermedia de abanicos aluviales y en la de terrazas más recientes deformados por la falla sureste. Los primeros resultados indican deformación cosísmica con deslizamiento inverso. Se interpreta también un bloqueo temporal del drenaje hacia el sur de la rambla de El Colmenar debido al levantamiento del bloque superior de la falla en un proceso cosísmico. Se describen evidencias de hasta tres paleoterremotos que, en un primer análisis sin datos de edad absoluta, habrían tenido lugar posteriormente a 125.000 años. La velocidad de deslizamiento no sería inferior a 0,06 mm/a y el período de recurrencia no sería mayor a 40.000 años. Estos primeros datos se podrán ajustar mediante dataciones absolutas que están en curso

    An improved model for fast and reliable harbour wave agitation assessment

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    ABSTRACT: This study presents the new advances achieved in the field of harbour agitation climate assessment. Based on the improvement of an elliptic mild-slope model (MSP), which realistically reconstructs waves inside any-sized basin, represented by high-detailed unstructured meshes, and forced by real-shaped outer spectral data. A new solver is proposed for high performance runs, which allow fast agitation hindcast for statistical downtime analysis within an iterative and multi-scenario approach. Also, a realistic assimilation of partial reflection processes in quays/docks/wharfs/breakwaters is proposed. The model has been successfully validated in several harbours of special relevance in Spain with in situ measurements, through the assimilation of the hybrid downscaling (Camus et al., 2011) technique combined with monochromatic-based wave spectral reconstruction.This work has been also partially funded under the RETOS program of the Spanish Ministry of Science, Innovation and Universities (BIA2017-87213-R). We would like to thank Puertos del Estado of Spain for providing spectral outer wave spectral forcing and wave agitation measurements, for gather/organize each Port Authority base data required

    Tratamiento del choque femoroacetabular mediante miniabordaje anterior. Resultados a corto plazo

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    El tratamiento quirúrgico del choque femoroacetabular (CFA) es un práctica clínica cada vez más frecuente en nuestra especialidad. Objetivo. Analizar los resultados clínicos y radiológicos de una primera serie de pacientes diagnosticados de CFA intervenidos mediante miniabordaje anterior. Material y métodos. Estudio prospectivo de 30 pacientes con una edad media de 36,2 años y un seguimiento mínimo de 12 meses. La valoración clínica se ha realizado mediante las escalas SF-36, WOMAC y NAHS. Evaluamos la corrección radiológica de la deformidad y la progresión o no del grado de coxartrosis. Resultados. Se obtuvo una corrección adecuada de la deformidad en el 93% de los casos, 27 de los 30 pacientes presentaron una mejoría clínica significativa en los test realizados. La complicación más frecuente fue la meralgia parestésica del femorocutáneo (5 casos), 1 paciente precisó de sustitución protésica por evolución del grado de coxartrosis. Conclusiones. El tratamiento del CFA mediante mini abordaje anterior es un procedimiento seguro y reproducible. Permite la corrección de las anormalidades anatómicas y la obtención de resultados clínicos satisfactorios en una cohorte de pacientes jóvenes.Surgical treatment of femoroacetabular impingement (FAI) is an increasingly common clinical practice in our speciality. Aim. To analyze the clinical and radiological results of a first series of patients diagnosed with a FAI treated with anterior mini-open approach. Material and methods. Prospective study of 30 patients with a mean age of 36.2 years with a minimum follow-up of 12 months was made. Clinical assessment was performed using the SF-36, WOMAC and NAHS scales. We evaluate the correction of the radiologic deformity and progression of the osteoarthritis grade. Results. An adequate correction of the deformity in 93% of cases was obtained, 27 of the 30 patients showed significant clinical improvement in all tests performed. The most common complication was meralgia paresthesia of the femoro-cutaneous nerve (5 cases), 1 patient required prosthetic replacement for progression of the osteoarthritis grade. Conclusions. FAI treatment by mini-open approach is a safe and reproducible procedure. This technique allows correction of anatomical abnormalities and obtains satisfactory clinical outcomes in a cohort of young patients
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