Análisis mediante SIG de los parámetros de producción de escorrentía

El umbral de escorrentía (P0) constituye uno de los parámetros clave en el estudio de la respuesta hidrológica de una cuenca. Resulta fundamental para el estudio de episodios y hace referencia a las pérdidas de precipitación, que tienen lugar en el sistema fluvial, desde el inicio del mismo hasta que se produce escorrentía. Uno de los métodos más usado para la estimación de este umbral es el desarrollado por el US Soil Conservation Service –SCS- (1972). Este método utiliza, entre otros, valores de pendiente, vegetación, usos del suelo y características hidrológicas del suelo. Aunque los valores de las tablas originales han sido modificados para el caso español por Témez, la experiencia demuestra que, en ambientes de rambla, se necesita una mayor adaptación, dada la especificidad del entorno morfoclimático. Este trabajo propone algunas modificaciones al método para mejorar la estimación del umbral de escorrentía en ramblas mediterráneas. Se presenta una aproximación, mediante SIG, al cálculo del P0 en el Bco de Carraixet, incluyendo el análisis de las características hidrogeomorfológicas de la cuenca para la estimación de la infiltración del suelo. Además, la estimación del parámetro en varias fechas permite un estudio diacrónico, que pone de manifiesto la evolución espacio-temporal de la producción de escorrentía, en función de los cambios en el uso del suelo

Scientific literature on pharmacoepidemiology. Bibliometric analysis of the period 1970-1999

Se estudió la producción científica sobre farmacoepidemiología durante el período de 1970 a 1999, a partir de los artículos originales recuperados en la base de datos IPA. Los 467 artículos recuperados procedían mayoritariamente de Estados Unidos (31.9%), predominando las áreas temáticas de farmacovigilancia y los estudios de utilización de medicamentos. La media de firmas por artículo era de 2.5 ± 1.3, con un grado de colaboración entre autores del 68.4% y un índice de transitoriedad del 80.1%. La distribución de autores por número de artículos publicados se ajustaba a la ley de Lotka. El país mayoritario de edición de las revistas en que se publicaron los artículos era Inglaterra (51.4%), siendo el inglés el idioma preferente (83.5%). La investigación científica sobre farmacoepidemiología presenta unas características que corresponden a una disciplina joven, siendo necesarios otros estudios que analicen la metodología y complejidad de dicha investigación.Objetive: The objetive of this study is to make a description of the scientific production on pharmacoepidemiology. Methods: We studied scientific literature on pharmacoepidemiology produced during the period 1970-99, using original articles retrieved from the IPA database. Results: The highest proportion of the 467 articles obtained originated from the United States (31.9%), and the most common thematic areas were pharmacovigilance and medicinal drug use. The mean number of authors per paper was 2.5 ± 1.3, with a 68.4% degree of collaboration and an 80.1% index of insularity. The distribution of authors per number of articles published was in accordance with Lotka’s law. Most journals were published in the United Kingdom (51.4%) and the most widely-used language of publication was English (83.5%). Conclusions: Scientific research into pharmacoepidemiology presents the characteristics that correspond to a young discipline, and further studies are required to analyse the methodology and complexity of such research

Evidencias arqueológicas de desplomes paramentales traumáticos en las Termas Marítimas de Baelo Claudia. Reflexiones arqueosismológicas

Durante los años 2011 a 2013 se han localizado, identificado y excavado parcialmente los restos de un nuevo complejo termal en la ciudad hispanorromana de Baelo Claudia (Tarifa, Cádiz), situado en el suburbium occidental de la ciudad, junto a la línea de costa. Denominadas Termas Marítimas, construidas en la primera mitad del s. II d.C. y abandonadas en época de Diocleciano/Constantino han sido excavadas estratigráficamente con detalle, habiéndose detectado la existencia de fases anteriores (que se remontan al s. II a.C.) y una continuidad de uso del ambiente en época tardorromana y moderna, vinculada con la explotación de los recursos marinos. Especialmente singular ha sido la constatación del desplome traumático de parte de los paramentos de las habitaciones del edificio en dos momentos concretos: por un lado en la Antigüedad Tardía (500 d.C. circa), ya que una unidad muraria de una de las habitaciones (H-3), anexa a la natatio, se localizó completamente derrumbada sobre el suelo, conexionada; y por otro, el desplome del muro oeste de la natatio y el oriental de la cisterna, estructuras de más de seis metros de longitud y cuatro de altura mínima conservada, desplomadas sobre los niveles de abandono del asentamiento en época bajomedieval o moderna (ss. XIV-XV d.C.). Se trata en ambas ocasiones de colapsos estructurales no habituales en circunstancias normales en los procesos de sedimentación arqueológica, por lo que es muy probable que su desplome se pueda vincular con eventos sísmicos u otras causas naturales similare

Chronostratigraphy and new vertebrate sites from the upper Maastrichtian of Huesca (Spain), and their relation with the K/Pg boundary

The transitional-continental facies of the Tremp Formation within the South-Pyrenean Central Unit (Spain) contain one of the best continental vertebrate records of the Upper Cretaceous in Europe. This Pyrenean area is therefore an exceptional place to study the extinction of continental vertebrates across the Cretaceous/Paleogene (K/Pg) boundary, being one of the few places in Europe that has a relatively continuous record ranging from the upper Campanian to lower Eocene. The Serraduy area, located on the northwest flank of the Tremp syncline, has seen the discovery of abundant vertebrate remains in recent years, highlights being the presence of hadrosaurid dinosaurs and eusuchian crocodylomorphs. Nevertheless, although these deposits have been provisionally assigned a Maastrichtian age, they have not previously been dated with absolute or relative methods. This paper presents a detailed stratigraphic, magnetostratigraphic and biostratigraphic study for the first time in this area, making it possible to assign most vertebrate sites from the Serraduy area a late Maastrichtian age, specifically within polarity chron C29r. These results confirm that the vertebrate sites from Serraduy are among the most modern of the Upper Cretaceous in Europe, being very close to the K/Pg boundary.Spanish Ministry of Economy and Competitiveness (grant numbers CGL2014-53548-P, CGL2015-64422-P and CGL2017-85038-P), cofinanced by the European Regional Development Fund; and by the Department of Education and Science of the Aragonese Government (grant numbers DGA groups H54 and E05), cofinanced by the European Social Fund (ESF). The paleomagnetic study was possible thanks to the complementary grants (beneficiaries of FPU, grant number CGL2010-16447/BTE: Brief Stays and Temporary Transfers, year 2015) supported by the Spanish Ministry of Culture, Education and Sports; and the Laboratory of paleomagnetism of the University of Burgos (Spain). Eduardo Puértolas Pascual is the recipient of a postdoctoral grant (SFRH/BPD/116759/2016) funded by the Fundação para a Ciência e Tecnologia (FCT-MCTES)

First-principles study of the ferroelastic phase transition in CaCl_2

First-principles density-functional calculations within the local-density approximation and the pseudopotential approach are used to study and characterize the ferroelastic phase transition in calcium chloride (CaCl_2). In accord with experiment, the energy map of CaCl_2 has the typical features of a pseudoproper ferroelastic with an optical instability as ultimate origin of the phase transition. This unstable optic mode is close to a pure rigid unit mode of the framework of chlorine atoms and has a negative Gruneisen parameter. The ab-initio ground state agrees fairly well with the experimental low temperature structure extrapolated at 0K. The calculated energy map around the ground state is interpreted as an extrapolated Landau free-energy and is successfully used to explain some of the observed thermal properties. Higher-order anharmonic couplings between the strain and the unstable optic mode, proposed in previous literature as important terms to explain the soft-phonon temperature behavior, are shown to be irrelevant for this purpose. The LAPW method is shown to reproduce the plane-wave results in CaCl_2 within the precision of the calculations, and is used to analyze the relative stability of different phases in CaCl_2 and the chemically similar compound SrCl_2.Comment: 9 pages, 6 figures, uses RevTeX

Trends and outcome of neoadjuvant treatment for rectal cancer: A retrospective analysis and critical assessment of a 10-year prospective national registry on behalf of the Spanish Rectal Cancer Project

Introduction: Preoperative treatment and adequate surgery increase local control in rectal cancer. However, modalities and indications for neoadjuvant treatment may be controversial. Aim of this study was to assess the trends of preoperative treatment and outcomes in patients with rectal cancer included in the Rectal Cancer Registry of the Spanish Associations of Surgeons. Method: This is a STROBE-compliant retrospective analysis of a prospective database. All patients operated on with curative intention included in the Rectal Cancer Registry were included. Analyses were performed to compare the use of neoadjuvant/adjuvant treatment in three timeframes: I)2006–2009; II)2010–2013; III)2014–2017. Survival analyses were run for 3-year survival in timeframes I-II. Results: Out of 14, 391 patients, 8871 (61.6%) received neoadjuvant treatment. Long-course chemo/radiotherapy was the most used approach (79.9%), followed by short-course radiotherapy ± chemotherapy (7.6%). The use of neoadjuvant treatment for cancer of the upper third (15-11 cm) increased over time (31.5%vs 34.5%vs 38.6%, p = 0.0018). The complete regression rate slightly increased over time (15.6% vs 16% vs 18.5%; p = 0.0093); the proportion of patients with involved circumferential resection margins (CRM) went down from 8.2% to 7.3%and 5.5% (p = 0.0004). Neoadjuvant treatment significantly decreased positive CRM in lower third tumors (OR 0.71, 0.59–0.87, Cochrane-Mantel-Haenszel P = 0.0008). Most ypN0 patients also received adjuvant therapy. In MR-defined stage III patients, preoperative treatment was associated with significantly longer local-recurrence-free survival (p < 0.0001), and cancer-specific survival (p < 0.0001). The survival benefit was smaller in upper third cancers. Conclusion: There was an increasing trend and a potential overuse of neoadjuvant treatment in cancer of the upper rectum. Most ypN0 patients received postoperative treatment. Involvement of CRM in lower third tumors was reduced after neoadjuvant treatment. Stage III and MRcN + benefited the most

Percutaneous mitral valve repair : Outcome improvement with operator experience and a second-generation device

Background and aim: Recent randomized data comparing percutaneous mitral valve repair (PMVR) versus optimal medical treatment in patients with functional MR (FMR) seemed to highlight the importance of the learning curve not only for procedural outcomes but also for patient selection. The aim of the study was to compare a contemporary series of patients undergoing PMVR using a second-generation Mitraclip device (Mitraclip NT) with previous cohorts treated with a first-generation system. Methods: This multicenter study collected individual data from 18 centers between 2012 and 2017. The cohort was divided into three groups according to the use of the first-generation Mitraclip during the first (control-1) or second half (control-2) or the Mitraclip NT sys-tem. Results: A total of 545 consecutive patients were included in the study. Among all, 182 (33.3%), 183 (33.3%), and 180 (33.3%) patients underwent mitral repair in the control-1, control-2, and NT cohorts, respectively. Procedural success was achieved in 93.3% of patients without differences between groups. Major adverse events did not statistically differ among groups, but there was a higher rate of pericardial effusion in the control-1 group (4.3%, 0.6%, and 2.6%, respectively; p = 0.025). The composite endpoint of death, surgery, and admission for congestive heart failure (CHF) at 12 months was lower in the NT group (23.5% in control-1, 22.5% in control-2, and 8.3% in the NT group; p = 0.032). Conclusions: The present paper shows that contemporary clinical outcomes of patients undergoing PMVR with the Mitraclip system have improved over time